JPWO2020166650A1 - Vehicle headlights and vehicle lighting equipment - Google Patents

Abstract

The vehicle headlight (1) diffracts the light source (52R, 52G, 52B) and the light (LR, LG, LB) emitted from the light source (52R, 52G, 52B) in a changeable phase modulation pattern. It includes a phase modulation element (54R, 54G, 54B) that emits light (DLR, DLG, DLB) having a predetermined light distribution pattern based on the phase modulation pattern, and a control unit (71). The control unit (71) adjusts the phase modulation pattern and changes the emission direction of the light (DLR, DLG, DLB) of the predetermined light distribution pattern while maintaining the predetermined light distribution pattern.

Description

The present invention relates to vehicle headlights and vehicle lighting fixtures.

As a vehicle lighting tool such as a vehicle headlight, various configurations capable of emitting light having a predetermined light distribution pattern are being studied. For example, Patent Document 1 below describes a vehicle lamp that forms a predetermined light distribution pattern by diffracting light using a hologram element which is a kind of phase modulation element.

Further, in Patent Document 1 below, a vehicle lamp is used as a vehicle headlight, and the hologram element is calculated so that the diffracted light reproduced by irradiating the reference light forms a low beam light distribution pattern. It is stated that it has been done. This vehicle lighting fixture used as a vehicle headlight forms a low beam light distribution pattern by a hologram element. For this reason, this vehicle lighting fixture used as a vehicle headlight does not require a shade that shields a part of the light emitted from the light source to form a low beam light distribution pattern, and can be miniaturized. Will be done.

Further, in Patent Document 1 below, any of a light source from which a vehicle lamp used as a vehicle headlight emits reference light, a plurality of hologram elements, and a plurality of hologram elements by changing the traveling direction of the reference light. It is described that one of them is provided with a liquid crystal prism for irradiating reference light. The plurality of hologram elements are formed with a hologram element calculated to form a low beam light distribution pattern and a light distribution pattern for urban areas where the outer shape of the light distribution pattern is different from the outer shape of the low beam light distribution pattern. Includes another holographic element, calculated in. For this reason, in this vehicle lighting fixture used as a vehicle headlight, the light distribution pattern of the emitted light is changed to the low beam light distribution pattern and the light distribution pattern for urban areas by switching the hologram element that irradiates the reference light. It is said that it can be changed to.

Japanese Unexamined Patent Publication No. 2012-146621

The vehicle headlight according to the first aspect of the present invention diffracts light emitted from the light source with a light source and a changeable phase modulation pattern, and emits light having a predetermined light distribution pattern based on the phase modulation pattern. A phase modulation element and a control unit are provided, and the control unit adjusts the phase modulation pattern and changes the light emission direction of the predetermined light distribution pattern while maintaining the predetermined light distribution pattern. It is characterized by.

Since the vehicle headlight of the first aspect can emit light having a predetermined light distribution pattern without using a shade like the vehicle headlight described in Patent Document 1, the above patent document. Similar to the vehicle headlight of No. 1, the size can be reduced as compared with the vehicle headlight using a shade. Further, in the vehicle headlight of the first aspect, as described above, the control unit adjusts the phase modulation pattern and emits the light of the predetermined light distribution pattern while maintaining the predetermined light distribution pattern. Change direction. Therefore, the vehicle headlight of the first aspect can suppress the driver from feeling uncomfortable as compared with the case where the predetermined light distribution pattern changes, and also changes the traveling direction of the vehicle and the vehicle. The light emission direction of a predetermined light distribution pattern can be changed according to the inclination in the pitch direction or the like. Therefore, the vehicle headlight of the first aspect can improve the visibility in the traveling direction. The phase modulation pattern is a pattern that modulates the phase of light incident on the phase modulation element.

Further, the vehicle headlight of the first aspect may further include a projection lens through which light emitted from the phase modulation element is transmitted.

The vehicle headlight of the first aspect can easily adjust the size of a predetermined light distribution pattern as compared with the case where the projection lens through which the light emitted from the phase modulation element is transmitted is not provided.

Further, in the vehicle headlight of the first aspect, the control unit may adjust the phase modulation pattern according to the inclination angle in the pitch direction of the vehicle and change the emission direction in the vertical direction.

With such a configuration, even if the vehicle is tilted in the pitch direction, light having a predetermined light distribution pattern can be emitted in an appropriate direction.

Further, in the vehicle headlight of the first aspect, the control unit may adjust the phase modulation pattern according to the speed of the vehicle and change the emission direction in the vertical direction.

Vehicle headlights tend to require distant visibility when traveling at high speeds than when traveling normally. In the vehicle headlight of the first aspect, the light emission direction of a predetermined light distribution pattern may be tilted upward so that the light is emitted farther when traveling at high speed. Therefore, the vehicle headlight of the first aspect has visibility of the traveling direction at high speed as compared with the case where the light emitting direction of the predetermined light distribution pattern does not change according to the speed of the vehicle. Can be improved.

Further, in the vehicle headlight of the first aspect, the control unit may adjust the phase modulation pattern according to the steering angle of the vehicle and change the emission direction to the left-right direction.

In this vehicle headlight of the first aspect, the light emission direction of a predetermined light distribution pattern changes in a direction tilted to the left and right according to a change in the traveling direction of the vehicle. For example, since the vehicle headlight of the first aspect can irradiate the traveling destination with light on a curved road, the light emitting direction of a predetermined light distribution pattern does not change according to the change of the traveling direction of the vehicle. Visibility on curved roads can be improved as compared with the case.

Further, in the vehicle headlight of the first aspect, when the control unit changes the emission direction, the emission direction in the predetermined light distribution pattern before the emission direction is changed is changed. The phase modulation pattern is adjusted so that light different from the light of the predetermined light distribution pattern is irradiated in the region that does not overlap with the predetermined light distribution pattern, and the brightness of the light emitted in the region is determined. It may be darker than the brightness of the region in the predetermined light distribution pattern before the emission direction is changed.

In the vehicle headlight of the first aspect, the light is irradiated in the region where the light is not irradiated by changing the emission direction of the predetermined light distribution pattern, and the light is irradiated in this region. The brightness of is darker than the brightness of this region in a predetermined light distribution pattern before the emission direction is changed. Therefore, in the vehicle headlight of the first aspect, the driver can recognize a predetermined light distribution pattern, and the visibility of the area irradiated with the light before changing the emission direction is lowered. , It is possible to suppress that the area irradiated with light different from the light of a predetermined light distribution pattern is conspicuous. Therefore, the vehicle headlight of the first aspect can further suppress the driver from feeling uncomfortable when changing the emission direction of the light of the predetermined light distribution pattern.

Further, in the vehicle headlight of the first aspect, the emission direction may be gradually changed.

In this vehicle headlight of the first aspect, the predetermined light distribution pattern gradually moves when the light emission direction of the predetermined light distribution pattern is changed. Therefore, this vehicle headlight can suppress the driver from feeling uncomfortable when changing the light emission direction of a predetermined light distribution pattern.

The vehicle headlight according to the second aspect of the present invention diffracts the light emitted from the light source with a light source and a changeable phase modulation pattern, and emits light having a predetermined light distribution pattern based on the phase modulation pattern. A phase modulation element and a control unit are provided, and the control unit adjusts the phase modulation pattern and continuously changes the outer shape of the predetermined light distribution pattern to obtain the predetermined light distribution pattern and outer shape. It is characterized by having different light distribution patterns.

In this vehicle headlight of the second aspect, the control unit adjusts the phase modulation pattern and continuously changes the outer shape of the light distribution pattern to obtain another light distribution pattern. Therefore, in the vehicle headlight of the second aspect, the driver feels uncomfortable as compared with the case where the outer shape of the light distribution pattern changes instantaneously as in the vehicle headlight described in Patent Document 1. Can be suppressed from remembering. The phase modulation pattern is a pattern that modulates the phase of light incident on the phase modulation element. Further, the change in the outer shape of the light distribution pattern includes the change in the size of the light distribution pattern.

Further, in the vehicle headlight of the second aspect, the control unit adjusts the phase modulation pattern according to the speed of the vehicle, and the predetermined light distribution pattern is smaller than the predetermined light distribution pattern. It may be an optical pattern.

Vehicle headlights tend to require distant visibility when traveling at high speeds than when traveling normally. The vehicle headlight of the second aspect can emit light having a light distribution pattern smaller than a predetermined light distribution pattern when traveling at high speed. Therefore, it is possible to make it easier for the driver's line of sight to be concentrated near the central portion in front of the vehicle as compared with the case where light having a predetermined light distribution pattern is emitted during high-speed driving, and it is possible to improve distant visibility. .. Further, since the vehicle headlight of the second aspect can have a light distribution pattern in which the emitted light distribution pattern is reduced according to the speed of the vehicle, it is possible to further suppress the driver from feeling uncomfortable.

Alternatively, the control unit may adjust the phase modulation pattern when the speed of the vehicle becomes a predetermined value or more, and make the predetermined light distribution pattern smaller than the predetermined light distribution pattern. good.

In this vehicle headlight of the second aspect, a light distribution pattern smaller than a predetermined light distribution pattern during high-speed driving is similar to the case where the control unit adjusts the phase modulation pattern according to the speed of the vehicle. Can emit light. Therefore, it is possible to make it easier for the driver's line of sight to be concentrated near the central portion in front of the vehicle as compared with the case where light having a predetermined light distribution pattern is emitted during high-speed driving, and it is possible to improve distant visibility. .. Further, in the vehicle headlight of the second aspect, since the control unit adjusts the phase modulation pattern in a specific case, it is possible to suppress an increase in the calculation load of the control unit.

Further, in the vehicle headlight of the second aspect, when the predetermined light distribution pattern is made smaller than the predetermined light distribution pattern, the outer shape of the light distribution pattern is smaller than the predetermined light distribution pattern. May have a shape similar to the outer shape of the predetermined light distribution pattern.

With such a configuration, the driver's feeling of discomfort is further suppressed as compared with the case where the outer shape of the light distribution pattern smaller than the predetermined light distribution pattern is not similar to the outer shape of the predetermined light distribution pattern. obtain.

Further, in the vehicle headlight of the second aspect, the control unit adjusts the phase modulation pattern according to the signal from the turn switch of the vehicle, and the predetermined light distribution pattern is expanded in the left-right direction. It may be a light distribution pattern.

In this vehicle headlight of the second aspect, the light distribution pattern changes to a light distribution pattern widened in the left-right direction in response to a signal from the turn switch of the vehicle. For example, since the vehicle headlight of the second aspect can irradiate the traveling destination with light at an intersection or the like, the light distribution pattern does not change according to the signal from the turn switch of the vehicle, as compared with the case where the light distribution pattern does not change. , Visibility at intersections, etc. can be improved.

Further, in the vehicle headlight of the second aspect, the control unit adjusts the phase modulation pattern according to the steering angle of the vehicle, and the predetermined light distribution pattern is expanded in the left-right direction. It is also good to make it.

In this vehicle headlight of the second aspect, the light distribution pattern changes to a light distribution pattern widened in the left-right direction according to a change in the traveling direction of the vehicle. For example, the vehicle headlight of the second aspect can irradiate the traveling destination with light on the curved road, so that the light distribution pattern does not change according to the change in the traveling direction of the vehicle. It can improve visibility on the road.

The vehicle lighting equipment according to the third aspect of the present invention is one of a light source that emits light, a phase modulation element that diffracts the light into a predetermined light distribution pattern, and the light diffracted by the phase modulation element. The control unit includes a light receiving element that receives light and a control unit, and the control unit has the predetermined light distribution pattern based on a signal from the light receiving element that receives a part of the light. It is characterized by determining whether it is a pattern.

According to this vehicle lamp according to the third aspect, it is determined whether or not the light distribution pattern of the light is a predetermined light distribution pattern based on the signal from the light receiving element that has received the light. As described above, the light distribution pattern of the light is formed by diffracting the light by the phase modulation element. Therefore, if the phase modulation element is defective, the light is distributed from the phase modulation element. The light pattern tends to collapse. Therefore, the control unit determines whether or not the light distribution pattern of the light is the predetermined light distribution pattern, so that a defect in the phase modulation element can be detected.

Further, in the vehicle lighting device of the third aspect, it is preferable that the light receiving element receives the light propagating in an optical path different from the optical path of the light emitted from the phase modulation element to the outside of the vehicle lighting device.

In this case, the light receiving element can be provided at a position away from the optical path emitted from the phase modulation element to the outside of the vehicle lighting equipment, and the light receiving element can be eliminated from such an optical path, so that the light distribution pattern can be satisfactorily obtained. The light distribution pattern can be effectively detected while maintaining the light distribution pattern.

Further, in the vehicle lighting equipment of the third aspect, in this case, the phase modulation element emits at least a part of the light emitted from the phase modulation element to the outside of the vehicle lighting equipment from the phase modulation element. It may be deflected to an optical path different from the optical path of light.

In this case, the optical path of light can be deflected without separately providing optical components, and the number of components can be reduced.

Further, in the vehicle lighting device of the third aspect, when the light receiving element receives the light propagating in an optical path different from the optical path of the light emitted from the phase modulation element to the outside of the vehicle lighting device, the phase is described. Further, a spectroscopic unit may be further provided which disperses a part of the light emitted from the modulation element into an optical path different from the optical path of the light emitted from the phase modulation element to the outside of the vehicle lighting equipment.

In this case, the optical path of the light emitted from the phase modulation element can be deflected more effectively.

Further, in the vehicle lighting device of the third aspect, the light receiving element may be an image pickup element that captures an image of the light.

In this case, the change in the light distribution pattern can be detected based on the image recognition, and the accuracy and accuracy in determining the light distribution pattern can be improved.

Further, in the vehicle lighting device of the third aspect, when the light receiving element is an image pickup element, the projection is arranged on an optical path different from the optical path of the light emitted from the phase modulation element to the outside of the vehicle lighting device. The image pickup device may further include a surface, and the image pickup device may take an image of the light projected on the projection surface.

By doing so, a clearer image can be captured, and the accuracy and accuracy of determining whether the light distribution pattern is a predetermined light distribution pattern can be further improved.

Further, in the vehicle lighting equipment of the third aspect, when the light receiving element is an image pickup element, the phase modulation element uses the light distribution pattern of the light emitted from the phase modulation element as the predetermined light distribution pattern. The light distribution pattern may be changed to a different one.

In this case, the light distribution pattern can be changed to an easier image recognition, and the accuracy and accuracy when determining the light distribution pattern based on the image recognition can be further improved.

Further, in the vehicle lighting device of the third aspect, when the light receiving element receives the light propagating in an optical path different from the optical path of the light emitted from the phase modulation element to the outside of the vehicle lighting device, the light receiving element receives the light. The element may be a light amount sensor arranged on an optical path different from the optical path of the light emitted from the phase modulation element to the outside of the vehicle lighting equipment.

By doing so, the configuration of the lighting fixture for a vehicle can be simplified.

Further, in the vehicle lighting equipment of the third aspect, the control unit constantly determines whether the light distribution pattern of the light received by the light receiving element is the predetermined light distribution pattern while the light source is on. You may.

In this case, since the defect of the phase modulation element is always determined, it is possible to grasp on-time that the phase modulation element has malfunctioned.

Further, in the vehicle lighting equipment of the third aspect, the control unit temporarily determines whether the light distribution pattern of the light received by the light receiving element is the predetermined light distribution pattern while the light source is on. You may judge.

In this case, the load on the control unit can be reduced as compared with the case where it is always determined whether the light distribution pattern is a predetermined light distribution pattern.

Further, in the vehicle lighting equipment of the third aspect, when the control unit temporarily determines the change in the light distribution pattern, the control unit has a predetermined period after the emission of the light from the light source is started. It may be determined whether or not the light distribution pattern of the light received by the light receiving element is the predetermined light distribution pattern.

In this case, since it is determined whether or not the light distribution pattern is a predetermined light distribution pattern at the timing when the light emission from the light source is started, it is possible to quickly grasp the defect of the phase modulation element and improve the safety.

Further, in the vehicle lighting equipment of the third aspect, when the control unit temporarily determines the change in the light distribution pattern, the control unit may use the control unit for a predetermined period while the vehicle equipped with the light source is stopped. , It may be determined whether or not the light distribution pattern of the light received by the light receiving element is the predetermined light distribution pattern.

In this case, the safety can be maintained more effectively by determining the light distribution pattern while the vehicle is stopped.

Further, in the vehicle lighting equipment of the third aspect, when the control unit temporarily determines the change in the light distribution pattern, the control unit determines whether the light distribution pattern of the light is the predetermined light distribution pattern. May be determined in a period of 1/30 second or less.

The time resolution of human vision is approximately 1/30 second. Therefore, by setting the period for the control unit to determine the light distribution pattern to 1/30 second or less, the optical path is deflected and the light distribution pattern is changed to a light distribution pattern different from the predetermined light distribution pattern. It becomes difficult for drivers and the like to recognize this, and safety can be maintained more effectively.

Further, in the vehicle lighting device of the third aspect, when the phase modulation element deflects the optical path of the light emitted from the phase modulation element to the outside of the vehicle lighting device to an optical path different from the optical path, or. When the phase modulation element changes the light distribution pattern of the light emitted from the phase modulation element to a light distribution pattern different from the predetermined light distribution pattern, the phase modulation element is LCOS (Liquid Crystal On Silicon). ) May be.

The LCOS is a phase modulation element that causes a difference in refractive index in the liquid crystal layer by changing the alignment pattern of the liquid crystal molecules. Therefore, if the phase modulation element is LCOS, the refractive index of the liquid crystal layer can be changed to easily change the optical path and the light distribution pattern of the light emitted from the phase modulation element. However, since the LCOS is composed of liquid crystal molecules as described above, the light distribution pattern tends to be greatly disrupted in the case of a defect. Therefore, by detecting the change in the light distribution pattern as described above, the defect of the phase modulation element can be detected more effectively.

It is a figure which shows schematically the headlight for a vehicle in 1st Embodiment of this invention. It is an enlarged view of the optical system unit shown in FIG. It is a front view of the phase modulation element shown in FIG. FIG. 3 is a diagram schematically showing a cross section of a part of the phase modulation element shown in FIG. 3 in the thickness direction. It is a block diagram which includes the headlight for a vehicle in 1st Embodiment of this invention. It is a figure which shows the predetermined light distribution pattern in 1st Embodiment of this invention. It is a figure which shows an example of the control flowchart of the control part in 1st Embodiment of this invention. FIG. 8A is a diagram showing an example of a state in which the emission direction of the low beam is changed, and FIG. 8B is a diagram showing another example of a state in which the emission direction of the low beam is changed. (C) is a diagram showing still another example of a state in which the emission direction of the low beam is changed. It is a figure which shows the example of the state which the emission direction of a low beam is changed and the light different from a low beam is emitted from a headlight for a vehicle. It is a figure which shows the optical system unit in the 3rd Embodiment of this invention in the same manner as FIG. It is a figure which shows the left expansion light distribution pattern which the predetermined light distribution pattern shown in FIG. 6 is expanded to the left side. It is a figure which shows the table in 4th Embodiment of this invention. It is a figure which shows an example of the control flowchart of the control part in 4th Embodiment of this invention. It is a figure which shows the example of the state of change of the light distribution pattern in 4th Embodiment of this invention. It is a block diagram which includes the headlight for a vehicle in 5th Embodiment of this invention. It is a figure which shows the table in 6th Embodiment of this invention. It is a figure which shows the example of the state of change of the light distribution pattern in the 6th Embodiment of this invention. It is a vertical sectional view schematically showing the lamp for a vehicle in 7th Embodiment of this invention. It is an enlarged view of the optical system unit shown in FIG. It is a front view schematically showing the light receiving element shown in FIG. It is a block diagram including the lamp for a vehicle shown in FIG. It is a figure which shows the light distribution pattern of a low beam. It is a figure which shows an example of the control flowchart of the control part in 7th Embodiment of this invention. It is a block diagram which includes the lamp for a vehicle in 8th Embodiment of this invention. It is a figure which shows an example of the control flowchart of the control part in 8th Embodiment of this invention. It is a figure which shows the optical system unit of the vehicle lamp according to the 9th Embodiment of this invention from the same viewpoint as FIG. It is a figure which shows an example of the control flowchart of the control part in 9th Embodiment of this invention. It is a front view which shows the projection plane in the 9th Embodiment of this invention together with the projected image. FIG. 5 is a front view schematically showing a projection plane according to a ninth embodiment of the present invention together with other projected images. It is a figure which shows the appearance that the image of light shown in FIG. 29 is collapsed. It is a figure which shows the optical system unit of the vehicle lamp according to the tenth embodiment of this invention from the same viewpoint as FIG. It is a figure which shows an example of the control flowchart of the control part in 10th Embodiment of this invention. It is a figure which shows the lamp for vehicle in 11th Embodiment of this invention from the same viewpoint as FIG. It is a figure which shows the light distribution pattern of a high beam.

Hereinafter, embodiments for implementing the vehicle headlights and vehicle lighting fixtures according to the present invention will be illustrated together with the attached drawings. The embodiments illustrated below are for facilitating the understanding of the present invention, and are not for limiting the interpretation of the present invention. The present invention can be modified or improved from the following embodiments without departing from the spirit of the present invention.

(First Embodiment)
A first embodiment as a first aspect of the present invention will be described. FIG. 1 is a diagram showing a vehicle headlight according to the present embodiment, and is a diagram schematically showing a cross section of the vehicle headlight in the vertical direction. The vehicle headlights of the present embodiment are for automobiles. Headlights for automobiles are generally provided in each of the left and right directions in front of the vehicle, and the left and right headlights are configured to be substantially symmetrical in the left and right directions. Therefore, in the present embodiment, one of the vehicle headlights will be described. As shown in FIG. 1, the vehicle headlight 1 of the present embodiment includes a housing 10, a lamp unit 20, an imaging lens 81, and a projection lens 82 as main configurations.

The housing 10 mainly includes a lamp housing 11, a front cover 12, and a back cover 13. The front of the lamp housing 11 is open, and the front cover 12 is fixed to the lamp housing 11 so as to close the opening. Further, an opening smaller than the front is formed behind the lamp housing 11, and the back cover 13 is fixed to the lamp housing 11 so as to close the opening.

The space formed by the lamp housing 11, the front cover 12 that closes the front opening of the lamp housing 11, and the back cover 13 that closes the rear opening of the lamp housing 11 is the light room R, and the light room R. A lamp unit 20, an imaging lens 81, and a projection lens 82 are housed therein.

The lamp unit 20 of the present embodiment includes a heat sink 30, a cooling fan 35, a cover 40, and an optical system unit 50 as main configurations, and is fixed to the housing 10 by a configuration (not shown).

The heat sink 30 has a metal base plate 31 extending in a substantially horizontal direction, and a plurality of heat radiation fins 32 are provided integrally with the base plate 31 on the lower surface side of the base plate 31. The cooling fan 35 is arranged with a gap from the heat radiation fin 32 and is fixed to the heat sink 30. The heat sink 30 is cooled by the air flow generated by the rotation of the cooling fan 35. Further, a cover 40 is arranged on the upper surface of the base plate 31 in the heat sink 30.

The cover 40 is fixed on the base plate 31 of the heat sink 30. The cover 40 has a substantially rectangular shape and is made of a metal such as aluminum. The optical system unit 50 is housed in the space inside the cover 40. An opening 40H through which the light emitted from the optical system unit 50 can be transmitted is formed in the front portion of the cover 40. In addition, in order to give the inner wall of the cover 40 light absorption, it is preferable that these inner walls are subjected to black alumite processing or the like. Since the inner wall of the cover 40 has light absorption, even when light is irradiated to these inner walls due to unintended reflection or refraction, the irradiated light is reflected and emitted from the opening 40H in an unintended direction. Can be suppressed.

The imaging lens 81 is a lens that forms an image of light emitted from the optical system unit 50 emitted from the opening 40H of the cover 40. The imaging lens 81 is arranged in front of the opening 40H of the cover 40, and is fixed to the housing 10 by a configuration (not shown). The imaging lens 81 of the present embodiment is a lens having an incident surface and an emitted surface formed in a convex shape.

The projection lens 82 is a lens that adjusts the divergence angle of the incident light. The projection lens 82 is arranged in front of the front focal point of the imaging lens 81, and is fixed to the housing 10 by a configuration (not shown). In the present embodiment, the projection lens 82 is a lens in which the entrance surface and the emission surface are formed in a convex shape, and the rear focus of the projection lens 82 is arranged so as to be located near the front focus or the front focus of the imaging lens 81. Will be done. The light imaged by the imaging lens 81 propagates while diverging after being imaged and is incident on the projection lens 82, and the divergence angle of this light is adjusted by the projection lens 82. The light whose divergence angle is adjusted by the projection lens 82 is emitted from the vehicle headlight 1 via the front cover 12.

FIG. 2 is an enlarged view of the optical system unit 50 shown in FIG. In addition, in FIG. 2, the description of the heat sink 30, the cover 40, etc. is omitted for ease of understanding. As shown in FIG. 2, the optical system unit 50 of the present embodiment includes a first light emitting optical system 51R, a second light emitting optical system 51G, a third light emitting optical system 51B, a first phase modulation element 54R, and a first phase modulation element 54R. It includes a two-phase modulation element 54G, a third phase modulation element 54B, and a synthetic optical system 55 as main configurations.

The first light emitting optical system 51R includes a first light source 52R and a first collimating lens 53R. The first light source 52R is a laser element that emits a laser beam having a predetermined wavelength band, and in the present embodiment, it is a semiconductor laser that emits a red laser beam having a power peak wavelength of, for example, 638 nm. The optical system unit 50 has a circuit board (not shown), and the first light source 52R is mounted on the circuit board.

The first collimating lens 53R is a lens that collimates the fast axis direction and the slow axis direction of the laser beam emitted from the first light source 52R. The red light LR emitted from the first collimating lens 53R is emitted from the first emission optical system 51R. Instead of the first collimating lens 53R, a collimating lens that collimates the fast axis direction of the laser beam and a collimating lens that collimates the slow axis direction may be individually provided.

The second light emitting optical system 51G includes a second light source 52G and a second collimating lens 53G, and the third light emitting optical system 51B includes a third light source 52B and a third collimating lens 53B. The light sources 52G and 52B are laser elements that emit laser light in a predetermined wavelength band, respectively. In the present embodiment, the second light source 52G is a semiconductor laser that emits a green laser light having a power peak wavelength of, for example, 515 nm, and the third light source 52B emits a blue laser light having a power peak wavelength of, for example, 445 nm. It is said to be a semiconductor laser. Therefore, in the present embodiment, the three light sources 52R, 52G, and 52B emit laser light having predetermined wavelength bands different from each other. The light sources 52G and 52B are mounted on the above-mentioned circuit board in the same manner as the above-mentioned first light source 52R.

The second collimating lens 53G is a lens that collimates the fast axis direction and the slow axis direction of the laser light emitted from the second light source 52G, and the third collimating lens 53B is the fast axis of the laser light emitted from the third light source 52B. It is a lens that collimates the direction and slow axis direction. The green light LG emitted from the second collimating lens 53G is emitted from the second light emitting optical system 51G, and the blue light LB emitted from the third collimating lens 53B is emitted from the third light emitting optical system 51B. Instead of these collimating lenses 53G and 53B, a collimating lens that collimates the fast axis direction of the laser beam and a collimating lens that collimates the slow axis direction may be individually provided.

The phase modulation elements 54R, 54G, and 54B are made capable of diffracting and emitting incident light and changing the light distribution pattern of the emitted light and the emission direction of the light forming the light distribution pattern. In the present embodiment, the phase modulation elements 54R, 54G, 54B are reflection type phase modulation elements that diffract and emit incident light while reflecting them, and specifically, a reflection type LCOS (Liquid Crystal On Silicon). ). The red light LR emitted from the first light emitting optical system 51R is incident on the first phase modulation element 54R, and the first phase modulation element 54R diffracts and emits the red light LR. The green light LG emitted from the second emission optical system 51G is incident on the second phase modulation element 54G, and the second phase modulation element 54G diffracts and emits the green light LG. The blue light LB emitted from the third emission optical system 51B is incident on the third phase modulation element 54B, and the third phase modulation element 54B diffracts and emits the blue light LB. In this way, the first optical DLR that is red is emitted from the first phase modulation element 54R, the second optical DLG that is green is emitted from the second phase modulation element 54G, and the second optical DLG that is green is emitted from the third phase modulation element 54B. The third optical DLB is emitted.

The synthetic optical system 55 includes a first optical element 55f and a second optical element 55s. The first optical element 55f is an optical element that synthesizes a first optical DLR emitted from the first phase modulation element 54R and a second optical DLG emitted from the second phase modulation element 54G. In the present embodiment, the first optical element 55f synthesizes the first optical DLR and the second optical DLG by transmitting the first optical DLR and reflecting the second optical DLG. Further, the second optical element 55s is an optical element that synthesizes the first optical DLR and the second optical DLG synthesized by the first optical element 55f and the third optical DLB emitted from the third phase modulation element 54B. It is an element. In the present embodiment, the second optical element 55s transmits the first optical DLR and the second optical DLG synthesized by the first optical element 55f and reflects the third optical DLB to obtain the first light. The DLR, the second optical DLG, and the third optical DLB are combined. Examples of such a first optical element 55f and a second optical element 55s include a wavelength selection filter in which an oxide film is laminated on a glass substrate. By controlling the type and thickness of the oxide film, it is possible to transmit light having a wavelength longer than a predetermined wavelength and reflect light having a wavelength shorter than this wavelength.

In this way, the light obtained by combining the first optical DLR, the second optical DLG, and the third optical DLB in the synthetic optical system 55 becomes white light, and this white light is emitted from the synthetic optical system 55. In FIGS. 1 and 2, the first optical DLR is indicated by a solid line, the second optical DLG is indicated by a broken line, and the third optical DLB is indicated by a alternate long and short dash line. These optical DLRs, DLGs, and DLBs are shown. It is shown off.

Next, the configurations of the first phase modulation element 54R, the second phase modulation element 54G, and the third phase modulation element 54B will be described in detail.

In this embodiment, the phase modulation elements 54R, 54G, 54B have the same configuration. Therefore, in the following, only the first phase modulation element 54R will be described in detail, and the description of the second phase modulation element 54G and the third phase modulation element 54B will be omitted as appropriate.

FIG. 3 is a front view schematically showing the first phase modulation element shown in FIG. 2. Note that FIG. 3 is a front view of the first phase modulation element 54R seen from the incident surface EFR side on which light is incident, and FIG. 3 is an incident region where the light LR emitted from the first light emitting optical system 51R is irradiated. Spot SR is shown. The first phase modulation element 54R of the present embodiment is formed to be substantially rectangular in front view. A plurality of modulation units MPR arranged in a matrix are formed on the first phase modulation element 54R. Each of these modulation unit MPRs includes a plurality of dots arranged in a matrix, and diffracts and emits light incident on the modulation unit MPR. The modulation unit MPR is formed so as to be located at one or more in the incident spot SR. Further, as shown in FIG. 3, an element drive circuit 60R is electrically connected to the first phase modulation element 54R, and this element drive circuit 60R is connected to one short side of the first phase modulation element 54R. It has a scanning line drive circuit and a data line drive circuit connected to one long side of the first phase modulation element 54R.

FIG. 4 is a diagram schematically showing a part of a cross section of the first phase modulation element shown in FIG. 3 in the thickness direction. As shown in FIG. 4, the first phase modulation element 54R of the present embodiment includes a silicon substrate 62, a drive circuit layer 63, a plurality of electrodes 64, a reflective film 65, a liquid crystal layer 66, and a transparent electrode 67. , And a translucent substrate 68 are provided as the main configurations.

The plurality of electrodes 64 are arranged in a matrix on one surface side of the silicon substrate 62 in a one-to-one correspondence with each of the dots. The drive circuit layer 63 is a layer in which a circuit connected to the scan line drive circuit and the data line drive circuit of the element drive circuit 60R shown in FIG. 3 is arranged, and is arranged between the silicon substrate 62 and the plurality of electrodes 64. Will be done. The translucent substrate 68 is arranged so as to face the silicon substrate 62 on one side of the silicon substrate 62, and is, for example, a glass substrate. The transparent electrode 67 is arranged on the surface of the translucent substrate 68 on the silicon substrate 62 side. The liquid crystal layer 66 has liquid crystal molecules 66a and is arranged between the plurality of electrodes 64 and the transparent electrodes 67. The reflective film 65 is arranged between the plurality of electrodes 64 and the liquid crystal layer 66, and is, for example, a dielectric multilayer film. The light LR emitted from the first light emitting optical system 51R is incident from the incident surface EFR on the side opposite to the silicon substrate 62 side of the translucent substrate 68.

As shown in FIG. 4, the light LR incident from the incident surface EFR on the side opposite to the silicon substrate 62 side of the translucent substrate 68 passes through the transparent electrode 67 and the liquid crystal layer 66, is reflected by the reflective film 65, and is a liquid crystal display. It passes through the layer 66 and the transparent electrode 67 and is emitted from the translucent substrate 68. When a voltage is applied between the specific electrode 64 and the transparent electrode 67, the orientation of the liquid crystal molecules 66a of the liquid crystal layer 66 located between the electrode 64 and the transparent electrode 67 changes. Due to the change in the orientation of the liquid crystal molecules 66a, the refractive index of the liquid crystal layer 66 located between the electrode 64 and the transparent electrode 67 changes, and the optical path length of the light LR transmitted through the liquid crystal layer 66 changes. Therefore, when the light LR passes through the liquid crystal layer 66 and is emitted from the liquid crystal layer 66, the phase of the light LR emitted from the liquid crystal layer 66 can change from the phase of the light LR incident on the liquid crystal layer 66. As described above, since the plurality of electrodes 64 are arranged for each dot DT in each modulation unit MPR, the voltage applied between the electrode 64 corresponding to each dot DT and the transparent electrode 67 is controlled. As a result, the orientation of the liquid crystal molecule 66a changes according to each dot DT, and the amount of change in the phase of the light emitted from each dot DT can be adjusted according to each dot DT. Since the light having different phases interferes with each other and is diffracted, the light emitted from each dot DT interferes with each other and is diffracted, and the diffracted light is emitted from the first phase modulation element 54R. Therefore, the first phase modulation element 54R diffracts the incident light and emits the incident light by adjusting the refractive index of the liquid crystal layer 66 in each dot DT, and obtains a desired light distribution pattern of the emitted light. Can be. Further, the first phase modulation element 54R changes the light distribution pattern of the emitted light by changing the refractive index of the liquid crystal layer 66 in each dot DT, or changes the direction of the emitted light to irradiate the light. You can change the area to be used.

In the present embodiment, the same phase modulation pattern is formed in each modulation unit MPR in the first phase modulation element 54R. Further, the same phase modulation pattern is formed in each modulation section of the second phase modulation element 54G, and the same phase modulation pattern is formed in each modulation section of the third phase modulation element 54B. In the present specification, the phase modulation pattern is a pattern that modulates the phase of incident light. In the present embodiment, the phase modulation pattern is a pattern of the refractive index of the liquid crystal layer 66 in each dot DT, and is also a pattern of the voltage applied between the electrode 64 and the transparent electrode 67 corresponding to each dot DT. Understandable. By adjusting this phase modulation pattern, the light distribution pattern of the emitted light can be changed to a desired light distribution pattern, or the light emission direction of the desired light distribution pattern can be changed.

FIG. 5 is a block diagram including a vehicle headlight according to the present embodiment. As shown in FIG. 5, in the present embodiment, the element drive circuit 60R, 60G, 60B, the power supply circuit 61R, 61G, 61B, the light switch 72, the tilt detection device 73, the steering sensor 74, the vehicle speed sensor 75, the storage unit 76, etc. Is electrically connected to the control unit 71. The control unit 71 may be provided in the lamp unit 20 or may be a part of an electronic control device of the vehicle. Further, the inclination detection device 73, the steering sensor 74, and the vehicle speed sensor 75 may be electrically connected to the control unit 71 via the electronic control device of the vehicle. As the control unit 71, for example, an integrated circuit such as a microcontroller, an IC (Integrated Circuit), an LSI (Large-scale Integrated Circuit), an ASIC (Application Specific Integrated Circuit), or an NC (Numerical Control) device can be used. Further, when the NC device is used, the control unit 71 may use a machine learning device or may not use a machine learning device. As will be described below, some configurations of the vehicle headlight 1 are controlled by the control unit 71.

The element drive circuit 60G is electrically connected to the phase modulation element 54G, and the element drive circuit 60B is electrically connected to the phase modulation element 54B. Similar to the element drive circuit 60R, the element drive circuits 60G and 60B are connected to a scanning line drive circuit connected to one short side of the phase modulation elements 54G and 54B and to one long side of the phase modulation elements 54R and 54B. It has a data line drive circuit to be used. The element drive circuits 60R, 60G, 60B adjust the voltage applied to the phase modulation elements 54R, 54G, 54B based on the signal input from the control unit 71, and adjust the phases of the phase modulation elements 54R, 54G, 54B, respectively. Adjust the modulation pattern. Therefore, it can be understood that the control unit 71 adjusts the phase modulation patterns of the phase modulation elements 54R, 54G, and 54B, respectively.

In the present embodiment, the phase modulation patterns in the phase modulation elements 54R, 54G, and 54B are the first optical DLR emitted from the phase modulation element 54R, the second optical DLG emitted from the phase modulation element 54G, and the phase modulation element. The third optical DLB emitted from 54B is a phase modulation pattern in which a predetermined light distribution pattern is formed by white light synthesized by the synthetic optical system 55. This predetermined light distribution pattern also includes a light intensity distribution. Therefore, in the present embodiment, each of the optical DLR, DLG, and DLB overlaps with the predetermined light distribution pattern, and the intensity distribution of each of the optical DLR, DLG, and DLB is the light in the predetermined light distribution pattern. The intensity distribution is based on the intensity distribution of. Further, in the portion where the light intensity is high in the predetermined light distribution pattern formed by the white light in which the optical DLR, DLG, and DLB are synthesized, the optical DLR, DLG, and DLB emitted from the phase modulation elements 54R, 54G, and 54B. The light intensity of each is also increased. Since the phase modulation elements 54R, 54G, and 54B have wavelength dependence, in the present embodiment, the phase modulation patterns of the phase modulation elements 54R, 54G, and 54B are different from each other. As a result of forming a predetermined light distribution pattern by the white light in which the light DLR, DLG, and DLB emitted from the phase modulation elements 54R, 54G, and DLB are combined, the phase modulation pattern in these phase modulation elements 54R, 54G, 54B. May have the same phase modulation pattern as each other.

As shown in FIGS. 1 and 2, the light DLR, DLG, and DLB emitted from the phase modulation elements 54R, 54G, and 54B are combined by the synthetic optical system 55, and the combined light is emitted from the opening 40H of the cover 40. Emit. The light DLRs, DLGs, and DLBs emitted from the aperture 40H propagate while diverging after being imaged by the imaging lens 81 and enter the projection lens 82, and the divergence angles of these optical DLRs, DLGs, and DLBs are the projection lens 82. It will be adjusted. The light DLR, DLG, and DLB light whose divergence angle is adjusted by the projection lens 82 is emitted from the vehicle headlight 1 via the front cover 12. Since these optical DLRs, DLGs, and DLBs are light having a light distribution pattern based on the phase modulation pattern in the phase modulation elements 54R, 54G, 54B, the light distribution pattern of the light emitted from the vehicle headlight 1 is a predetermined arrangement. It becomes an optical pattern. Further, by adjusting the phase modulation pattern in the phase modulation elements 54R, 54G, 54B, the emission direction of the light of this predetermined light distribution pattern emitted from the vehicle headlight 1 is maintained at the predetermined light distribution pattern. Can be changed while.

The power supply circuit 61R shown in FIG. 5 is electrically connected to the light source 52R, the power supply circuit 61G is electrically connected to the light source 52G, and the power supply circuit 61B is electrically connected to the light source 52B. A power supply (not shown) is connected to these power supply circuits 61R, 61G, 61B. Each of the power supply circuits 61R, 61G, 61B adjusts the power supplied from the power supply to the light sources 52R, 52G, 52B based on the signal input from the control unit 71, and lasers emitted from the light sources 52R, 52G, 52B. Adjust the light intensity. The power supply circuits 61R, 61G, 61B may adjust the power supplied to the light sources 52R, 52G, 52B by PWM (Pulse Width Modulation) control. In this case, by adjusting the duty cycle, the intensity of the laser light emitted from these light sources 52R, 52G, 52B is adjusted.

The light switch 72 is a switch for instructing the driver to emit or not emit light from the vehicle headlight 1. For example, when the light switch 72 is turned on, the light switch 72 outputs a signal instructing the emission of light from the vehicle headlight 1.

The inclination detection device 73 is a device that detects an inclination angle of the vehicle in the pitch direction with respect to the road surface. The tilt detection device 73 sends a signal of the detected tilt angle to the control unit 71. Examples of the configuration of the tilt detection device 73 include a configuration using a vehicle height sensor and a configuration using a gyro sensor.

The steering sensor 74 is a sensor that detects the rotation angle of the steering wheel of the vehicle, that is, the steering angle of the vehicle, and sends a signal of the detected steering angle to the control unit 71. The steering sensor 74 detects the right steering angle and the left steering angle while distinguishing them from different steering angles. The vehicle speed sensor 75 is a sensor that detects the traveling speed of the vehicle, and sends a signal of the detected traveling speed to the control unit 71.

The storage unit 76 of the present embodiment contains information on a predetermined light distribution pattern formed by the combined light of the light DLR, DLG, and DLB emitted from the phase modulation elements 54R, 54G, and 54B, and information indicating the vehicle state. Stores multiple associated tables. Although the details will be described later, the vehicle headlight 1 of the present embodiment is configured to change the emission direction of a predetermined light distribution pattern according to the inclination angle, the steering angle, and the vehicle speed in the pitch direction of the vehicle. There is. In the present embodiment, the information regarding the predetermined light distribution pattern is the phase modulation pattern in each modulation unit of the phase modulation elements 54R, 54G, 54B when forming the predetermined light distribution pattern, and the information regarding the predetermined light distribution pattern is used. The phase modulation pattern is set according to the emission direction. The emission direction of the predetermined light distribution pattern includes a reference emission direction, a plurality of directions inclined in the vertical direction with respect to the reference emission direction, and a plurality of directions inclined in the left-right direction with respect to the reference emission direction. A direction and a plurality of directions inclined in the vertical direction and the horizontal direction with respect to the emission direction of the reference are included. Therefore, the phase modulation pattern corresponding to each of the plurality of emission directions is stored in the storage unit 76 as information regarding a predetermined light distribution pattern. In the present embodiment, a plurality of tables in which a plurality of phase modulation patterns and a steering angle of the vehicle are associated are provided according to the inclination angle in the pitch direction of the vehicle. Further, a plurality of tables according to the inclination angle in the pitch direction are provided in the vehicle according to the speed. Therefore, each phase modulation pattern stored in the storage unit 76 is associated with a vehicle speed, a tilt angle in the pitch direction of the vehicle, and a steering angle. Further, the storage unit 76 also stores information regarding the intensity of the laser beam emitted from the light sources 52R, 52G, 52B and the like. In the present embodiment, the intensity of the laser beam emitted from the light sources 52R, 52G, 52B is set to a predetermined intensity. The storage unit 76 may be a non-volatile memory or a volatile memory as long as it can hold the stored information, and may be configured so that the stored information can be rewritten. Examples of the storage unit 76 include magnetic disks represented by HD (Hard Disk), semiconductor memories, optical disks, and the like.

FIG. 6 is a diagram showing a predetermined light distribution pattern in the present embodiment. In FIG. 6, S indicates a horizontal line, and the light distribution pattern is shown by a thick line. The light distribution pattern is a light distribution pattern formed on a vertical surface 25 m away from the vehicle, and the light distribution pattern is emitted. The direction is the reference emission direction. As shown in FIG. 6, the predetermined light distribution pattern in this embodiment is a low beam light distribution pattern PL. Among the low beam light distribution pattern PL shown in FIG. 6, the region LA1 is the region having the highest light intensity, and the light intensity decreases in the order of the region LA2 and the region LA3. That is, the phase modulation pattern in each of the phase modulation elements 54R, 54G, 54B is a phase modulation pattern in which the combined light forms a light distribution pattern including the intensity distribution of the low beam. The first light DLR emitted from the first phase modulation element 54R is the light of the red component of the low beam light distribution pattern PL, and the second light DLG emitted from the second phase modulation element 54G is the low beam light distribution. The light of the green component of the pattern PL, and the third light DLB emitted from the third phase modulation element 54B is the light of the blue component of the low beam light distribution pattern PL.

Next, the operation of the vehicle headlight 1 of the present embodiment will be described. Specifically, the operation of changing the emission direction of the low beam will be described. FIG. 7 is a diagram showing an example of a control flowchart of the control unit of the present embodiment.

(Step SP1)
In the present embodiment, first, when the light switch 72 is turned on and a signal instructing the emission of light from the light switch 72 is input to the control unit 71, the control flow of the control unit 71 proceeds to step SP2. On the other hand, if this signal is not input to the control unit 71 in step SP1, the control flow of the control unit 71 proceeds to step SP3.

(Step SP2)
In this step, the control unit 71 emits a low beam from the vehicle headlight 1, and the light sources 52R, 52G, 52B, and the phase modulation element 54R so that the emission direction of the low beam is in a direction corresponding to the vehicle state. , 54G, 54B are controlled. Specifically, the control unit 71 outputs a predetermined signal to the power supply circuits 61R, 61G, 61B. The power supply circuits 61R, 61G, 61B supply predetermined power from the power supply to the light sources 52R, 52G, 52B based on the signal input from the control unit 71. Therefore, the light sources 52R, 52G, and 52B each emit laser light of a predetermined intensity, and the light LR, LG, and LB of a predetermined intensity emit light from the emission optical systems 51R, 51G, and 51B, respectively. These optical LRs, LGs, and LBs are incident on the corresponding phase modulation elements 54R, 54G, and 54B, respectively. Further, the control unit 71 outputs a signal of the traveling speed of the vehicle output from the vehicle speed sensor 75, a signal of the inclination angle of the vehicle in the pitch direction with respect to the road surface output from the inclination detection device 73, and a vehicle output from the steering sensor 74. Refer to the table stored in the storage unit 76 based on the signal of the steering angle of. Then, the control unit 71 is based on the phase modulation pattern according to the steering angle among the phase modulation patterns of the phase modulation elements 54R, 54G, 54B in the table according to the detected vehicle speed and the inclination angle in the pitch direction of the vehicle. The signal is output to the element drive circuits 60R, 60G, 60B.

The element drive circuits 60R, 60G, 60B adjust the voltage applied to each dot DT of the phase modulation elements 54R, 54G, 54B based on this signal input from the control unit 71, respectively. This voltage is a voltage that makes the phase modulation pattern of the phase modulation elements 54R, 54G, 54B into a phase modulation pattern based on the control unit 71 when the control unit 71 outputs a signal.

As described above, the optical LR, LG, and LB are incident on the corresponding phase modulation elements 54R, 54G, and 54B, respectively. Therefore, the optical DLR, DLG, DLB based on the phase modulation pattern of the phase modulation elements 54R, 54G, 54B is emitted from the phase modulation elements 54R, 54G, 54B, and the light obtained by synthesizing the optical DLR, DLG, DLB is for a vehicle. Emit from the headlight 1. As described above, in the present embodiment, the predetermined light distribution pattern is the low beam light distribution pattern PL, and the phase modulation patterns of the phase modulation elements 54R, 54G, 54B are the detected vehicle speed and the inclination in the pitch direction of the vehicle. The phase modulation pattern is set according to the angle and the steering angle. Therefore, the light of the white low beam light distribution pattern PL is emitted in the emission direction according to the detected tilt angle, steering angle, and speed of the vehicle in the pitch direction. Then, the control flow of the control unit 71 proceeds to step SP1, and when the light switch 72 is on, the process proceeds to step SP2. Therefore, when the vehicle state changes, that is, when any one of the vehicle speed, the inclination angle in the pitch direction of the vehicle, and the steering angle changes, the control unit 71 outputs a signal to the element drive circuits 60R, 60G, and 60B. Will be changed according to the vehicle speed, the inclination angle in the pitch direction of the vehicle, and the steering angle. Then, the emission direction of the low beam emitted from the vehicle headlight 1 is changed. Therefore, the control unit 71 adjusts the phase modulation pattern in each modulation unit of the phase modulation elements 54R, 54G, 54B according to the vehicle speed, the tilt angle in the pitch direction of the vehicle, and the steering angle, and the low beam light distribution pattern PL. It can be understood that the light emission direction of the low beam light distribution pattern PL is changed while maintaining the above.

In the present embodiment, the control unit 71 simultaneously controls the phase modulation elements 54R, 54G, 54B and the light sources 52R, 52G, 52B. However, the control unit 71 may sequentially perform these controls. Further, the control unit 71 emits laser light of a predetermined intensity from the light sources 52R, 52G, 52B until the control flow of the control unit 71 proceeds to step SP3 described later.

In the present embodiment, the control unit 71 is used from the vehicle headlights 1 of the optical DLR, DLG, and DLB when the inclination angle in the pitch direction of the vehicle, which is one of the information indicating the vehicle state, is an angle of inclination to the upper side. The phase modulation elements 54R, 54G, and 54B are controlled so that the emission direction is tilted downward according to the tilt angle. Further, in the control unit 71, when the tilt angle in the pitch direction of the vehicle is tilted downward, the emission directions of the optical DLR, DLG, and DLB from the vehicle headlight 1 are tilted upward according to the tilt angle. The phase modulation elements 54R, 54G, 54B are controlled so as to be in the direction. The angle tilted according to the tilt angle is small when the tilt angle is small, and large when the tilt angle is large. That is, the plurality of tables stored in the storage unit 76 are such that the emission direction is as described above. Therefore, the control unit 71 controls the phase modulation elements 54R, 54G, 54B based on such a table to adjust the phase modulation pattern according to the tilt angle of the vehicle, and the vehicle of the optical DLR, DLG, DLB. The emission direction from the headlight 1 is changed to the vertical direction.

Further, in the present embodiment, the control unit 71 emits light DLR, DLG, and DLB from the vehicle headlight 1 when the steering angle, which is one of the information indicating the vehicle state, indicates steering to the left. The phase modulation elements 54R, 54G, and 54B are controlled so that the light is tilted to the left according to the steering angle. Further, when the steering angle indicates steering to the right, the control unit 71 makes the emission directions of the optical DLR, DLG, and DLB from the vehicle headlight 1 tilted to the right according to the steering angle. , Controls the phase modulation elements 54R, 54G, 54B. The angle tilted according to the steering angle is small when the steering angle is small, and large when the steering angle is large. That is, the plurality of tables stored in the storage unit 76 are such that the emission direction is as described above. Therefore, the control unit 71 controls the phase modulation elements 54R, 54G, 54B based on such a table to adjust the phase modulation pattern according to the steering angle of the vehicle, and the vehicle of the optical DLR, DLG, DLB. The emission direction from the headlight 1 is changed to the left-right direction.

Further, in the present embodiment, the control unit 71 sets the emission direction of the optical DLR, DLG, and DLB from the vehicle headlight 1 when the speed of the vehicle, which is one of the information indicating the vehicle state, is equal to or higher than a predetermined value. The phase modulation elements 54R, 54G, and 54B are controlled so as to be tilted upward by a predetermined angle. That is, the plurality of tables stored in the storage unit 76 are such that the emission direction is as described above. Therefore, the control unit 71 controls the phase modulation elements 54R, 54G, 54B based on such a table to adjust the phase modulation pattern according to the speed of the vehicle, and the optical DLR, DLG, DLB for the vehicle. The emission direction from the headlight 1 is changed to the vertical direction.

For example, when the inclination angle in the pitch direction of the vehicle is an angle of inclination to the upper side, the steering angle indicates steering to the left, and the speed of the vehicle is less than a predetermined value, the optical DLR, DLG, and DLB headlights for the vehicle are used. The emission direction from the lamp 1 is a direction that is tilted downward according to the tilt angle and tilted to the left according to the steering angle. Further, when the tilt angle in the pitch direction of the vehicle is an angle of tilting downward, the steering angle indicates steering to the right, and the speed of the vehicle is equal to or higher than a predetermined value, the optical DLR, DLG, DLB vehicle headlights. The exit direction from 1 is a direction that is tilted upward according to the tilt angle, tilted to the right according to the steering angle, and further tilted upward by a predetermined angle. That is, the plurality of tables stored in the storage unit 76 are such that the emission direction is as described above.

FIG. 8A is a diagram showing an example of a state in which the emission direction of the low beam is changed, and FIG. 8B is a diagram showing another example of a state in which the emission direction of the low beam is changed. 8 (C) is a diagram showing still another example of a state in which the emission direction of the low beam is changed. Specifically, FIG. 8A is a diagram showing a state in which the emission direction of the low beam is tilted downward according to the tilt angle in the pitch direction of the vehicle. FIG. 8B is a diagram showing a state in which the emission direction of the low beam is tilted to the left according to the steering angle of the vehicle. FIG. 8C is a diagram showing a state in which the emission direction of the low beam is tilted upward according to the speed of the vehicle. In addition, in FIG. 8A, FIG. 8B, and FIG. 8C, the state before the emission direction of the low beam is changed is shown by a broken line. Further, in FIGS. 8 (A), 8 (B), and 8 (C), in order to facilitate understanding, a line indicating a boundary between the region LA1 and the region LA2 in the low beam light distribution pattern PL and the region LA2 are shown. The description of the line indicating the boundary between the area LA3 and the area LA3 is omitted.

In the state shown in FIG. 8A, the tilt angle of the vehicle in the pitch direction is an angle of tilting upward, and the vehicle is tilted upward with respect to the road surface. As such a state, for example, a state in which luggage or the like is loaded on the rear side of the vehicle can be mentioned. Since the vehicle is tilted upward with respect to the road surface, the low beam light distribution pattern PL before the emission direction is changed is the state in which the low beam light distribution pattern PL is moved upward from the position of the low beam light distribution pattern PL shown in FIG. Become. However, in the present embodiment, in step SP2, the emission direction of the low beam is changed to a direction inclined downward. Therefore, as shown in FIG. 8A, the low beam light distribution pattern PL can be brought closer to the position of the low beam light distribution pattern PL shown in FIG. The state shown in FIG. 8B is a state in which the vehicle is steered to the left. Therefore, in the present embodiment, in step SP2, the emission direction of the low beam is changed to the direction tilted to the left, and the light distribution pattern PL of the low beam is moved to the left from the position before the emission direction of the low beam is changed. Will be. The state shown in FIG. 8C is a state in which the speed of the vehicle is equal to or higher than a predetermined value. Therefore, in the present embodiment, in step SP2, the emission direction of the low beam is changed to a direction tilted upward by a predetermined angle, and the light distribution pattern PL of the low beam is moved upward from the position before the emission direction of the low beam is changed. It will be in a moved state.

(Step SP3)
In this step, the control unit 71 controls the light sources 52R, 52G, and 52B so that the light from the vehicle headlight 1 is not emitted. Specifically, when the control flow of the control unit 71 proceeds to step SP3 without inputting the signal instructing the emission of light from the light switch 72 to the control unit 71 in step SP1 as described above, the control unit 71 , The light sources 52R, 52G, 52B are controlled to make the laser light from the light sources 52R, 52G, 52B non-emission. In this case, the power supply circuits 61R, 61G, 61B stop the supply of electric power from the power supply to the light sources 52R, 52G, 52B based on the signal input from the control unit 71. Therefore, the light sources 52R, 52G, and 52B do not emit the laser light, and the vehicle headlight 1 does not emit the light. Then, the control flow of the control unit 71 proceeds to step SP1.

As described above, the vehicle headlight 1 of the present embodiment changes the emission direction of the low beam according to the inclination angle, the steering angle, and the speed of the vehicle. The vehicle headlight 1 may change the emission direction of the low beam according to at least one of the vehicle tilt angle, steering angle, and speed. For example, when the vehicle headlight 1 changes the emission direction of the low beam according to the speed, it is not necessary to change the emission direction of the low beam according to the steering angle. That is, when the speed of the vehicle is equal to or higher than a predetermined value, the control unit 71 changes the emission direction of the low beam to a direction tilted upward by a predetermined angle according to the speed of the vehicle, but changes the emission direction of the low beam according to the steering angle. It is not necessary to change it in the left-right direction. Further, the control unit 71 does not have to change the emission direction of the low beam in the vertical direction according to the tilt angle when the tilt angle of the vehicle is not more than a predetermined value, and when the steering angle of the vehicle is not more than a predetermined value, the steering angle is steered. It is not necessary to change the emission direction of the low beam to the left-right direction according to the situation. Further, for example, when the vehicle speed is slow, the control unit 71 reduces the angle at which the low beam emission direction is tilted upward, and when the vehicle speed is high, the control unit 71 increases the angle at which the low beam emission direction is tilted upward. May be.

By the way, the headlight for a vehicle may change the direction of the emitted light according to a change in the traveling direction of the vehicle, an inclination in the pitch direction of the vehicle, or the like in order to improve visibility in the traveling direction. Therefore, even in a miniaturized vehicle headlight such as the vehicle headlight used as the vehicle headlight of Patent Document 1, the headlight is emitted according to the traveling state of the vehicle, the inclination of the vehicle in the pitch direction, and the like. There is a demand to improve the visibility of the traveling direction by changing the direction of the light.

Therefore, the vehicle headlight 1 of the present embodiment includes light sources 52R, 52G, 52B, phase modulation elements 54R, 54G, 54B, and a control unit 71. The phase modulation element 54R diffracts the light emitted from the light source 52R with a changeable phase modulation pattern, and emits an optical DLR having a light distribution pattern based on the phase modulation pattern. The phase modulation element 54G diffracts the light emitted from the light source 52G with a changeable phase modulation pattern, and emits an optical DLG having a light distribution pattern based on the phase modulation pattern. The phase modulation element 54B diffracts the light emitted from the light source 52B with a changeable phase modulation pattern, and emits an optical DLB having a light distribution pattern based on the phase modulation pattern. In the vehicle headlight 1, a low beam light distribution pattern PL is formed by the combined light of these lights DLR, DLG, and DLB, and the low beam is emitted from the vehicle headlight 1.

Therefore, the vehicle headlight 1 of the present embodiment emits the light of the low beam light distribution pattern PL without using a shade, like the vehicle headlight used as the vehicle headlight described in Patent Document 1. This can be achieved, and the size can be reduced as compared with the vehicle headlights that use shades, similar to the vehicle headlights used as the vehicle headlights of Patent Document 1.

Further, in the vehicle headlight 1 of the present embodiment, the control unit 71 adjusts the phase modulation pattern in each of the modulation units of the phase modulation elements 54R, 54G, 54B, and arranges the optical DLR, DLG, and DLB respectively. While maintaining the optical pattern, the emission directions of the optical DLR, DLG, and DLB from the vehicle headlight 1 are changed. Therefore, the vehicle headlight 1 of the present embodiment can suppress the driver from feeling uncomfortable as compared with the case where the low beam light distribution pattern PL changes. Further, the vehicle headlight 1 of the present embodiment can change the emission direction of the low beam according to a change in the traveling direction of the vehicle, an inclination in the pitch direction of the vehicle, and the like. Therefore, the vehicle headlight 1 of the present embodiment can improve the visibility in the traveling direction.

Further, the vehicle headlight 1 of the present embodiment does not include a device for integrally rotating or moving the lighting unit 20, the imaging lens 81, and the projection lens 82 with respect to the housing 10. However, since the emission direction of the low beam can be changed, it is possible to suppress the increase in size.

Further, in the vehicle headlight 1 of the present embodiment, the control unit 71 adjusts the phase modulation pattern in each of the phase modulation elements 54R, 54G, 54B according to the inclination angle in the pitch direction of the vehicle. While maintaining the respective light distribution patterns of the optical DLR, DLG, and DLB, the emission directions of the optical DLR, DLG, and DLB from the vehicle headlight 1 are changed in the vertical direction.

Therefore, even if the vehicle is tilted in the pitch direction, the low beam can be emitted in an appropriate direction. For example, as shown in FIG. 8A, even when the vehicle is tilted upward with respect to the road surface, it is possible to suppress the position of the low beam light distribution pattern PL from moving upward.

Further, in the vehicle headlight 1 of the present embodiment, the control unit 71 adjusts the phase modulation pattern in each of the modulation units of the phase modulation elements 54R, 54G, 54B according to the steering angle of the vehicle, and the optical DLR, While maintaining the respective light distribution patterns of DLG and DLB, the emission directions of the optical DLR, DLG, and DLB from the vehicle headlight 1 are changed to the left and right.

Therefore, in the vehicle headlight 1 of the present embodiment, the emission direction of the low beam changes in the direction tilted to the left and right according to the change in the traveling direction of the vehicle. For example, as shown in FIG. 8B, the vehicle headlight 1 of the present embodiment can irradiate the traveling destination with light on the curved road WR. Therefore, the vehicle headlight 1 of the present embodiment can improve the visibility in the curved road WR as compared with the case where the emission direction of the low beam does not change according to the change in the traveling direction of the vehicle.

Further, in the vehicle headlight 1 of the present embodiment, the control unit 71 adjusts the phase modulation pattern in each of the modulation units of the phase modulation elements 54R, 54G, 54B according to the speed of the vehicle, and the optical DLR, DLG. , The emission directions of the optical DLR, DLG, and DLB from the vehicle headlight 1 are changed in the vertical direction while maintaining the respective light distribution patterns of the DLB.

Vehicle headlights tend to require distant visibility when traveling at high speeds than when traveling normally. As shown in FIG. 8C, the vehicle headlight 1 of the present embodiment is farther away with the low beam emission direction tilted upward during high-speed traveling in which the vehicle speed is equal to or higher than a predetermined value. Can be illuminated with light. Therefore, the vehicle headlight 1 of the present embodiment can improve the visibility of the traveling direction during high-speed traveling as compared with the case where the emission direction of the low beam does not change according to the speed of the vehicle.

From the viewpoint of suppressing the driver from feeling uncomfortable when changing the emission direction of the low beam, it is preferable that the emission direction of the low beam is gradually changed. That is, the control unit 71 gradually changes the phase modulation pattern in each of the modulation units of the phase modulation elements 54R, 54G, 54B, and maintains the respective light distribution patterns of the optical DLR, DLG, and DLB, while the optical DLR, The emission direction of the DLG and DLB from the vehicle headlight 1 is gradually changed. For example, when the emission direction of the low beam is changed from the reference emission direction to a direction tilted by a predetermined angle in a predetermined direction, the control unit 71 sequentially increases the angle tilted in the predetermined direction with respect to the reference emission direction to become a predetermined angle. As described above, the phase modulation elements 54R, 54G, and 54B are controlled based on the plurality of tables stored in the storage unit 76. That is, the control unit 71 sequentially changes the phase modulation pattern in each of the modulation units of the phase modulation elements 54R, 54G, 54B at a predetermined time interval to obtain a phase modulation pattern in which the emission direction is tilted by a predetermined angle in a predetermined direction. do. With such a configuration, the light distribution pattern PL of the low beam gradually moves when the emission direction of the low beam is changed, and the driver feels uncomfortable compared to the case where the emission direction of the low beam can be changed instantaneously. It can suppress remembering. From the viewpoint of suppressing the driver from feeling uncomfortable, the control unit 71 uses the phase modulation elements 54R, 54G, so that the movement of the low beam light distribution pattern PL is recognized as smooth movement by human vision. It is preferable to sequentially change the phase modulation pattern in each modulation unit of 54B.

Further, the vehicle headlight 1 of the present embodiment includes a projection lens through which the light DLR, DLG, DLB emitted from the phase modulation elements 54R, 54G, 54B is transmitted.

Therefore, the vehicle headlight 1 of the present embodiment has a low beam light distribution pattern as compared with the case where the vehicle headlight 1 does not have a projection lens through which the light DLR, DLG, DLB emitted from the phase modulation elements 54R, 54G, 54B is transmitted. The size of the PL can be easily adjusted.

(Second Embodiment)
Next, a second embodiment as the first aspect of the present invention will be described in detail. The same or equivalent components as those in the first embodiment are designated by the same reference numerals and duplicated description will be omitted unless otherwise specified.

The vehicle headlights of the present embodiment are for automobiles as in the first embodiment. Further, the configuration of the vehicle headlight 1 of the present embodiment is the same as that of the vehicle headlight 1 of the first embodiment. Further, the control flowchart of the control unit 71 of the present embodiment is the same as the control flowchart of the control unit 71 of the first embodiment. However, in the present embodiment, the control of the phase modulation elements 54R, 54G, 54B of the control unit 71 in step SP2 is different from the control in the first embodiment. Therefore, the operation of the vehicle headlight 1 of the present embodiment will be described with reference to FIG. 7.

In the present embodiment, in step SP2, the control unit 71 adjusts the phase modulation pattern in each modulation unit of the phase modulation elements 54R, 54G, 54B according to the tilt angle, steering angle, and speed of the vehicle, and optical. While maintaining the light distribution patterns of DLR, DLG, and DLB, the emission directions of the optical DLR, DLG, and DLB from the vehicle headlight 1 are changed, and the light different from the optical DLR, DLG, and DLB is phase-modulated. It is emitted from the elements 54R, 54G, and 54B, respectively. That is, in the present embodiment, among the phase modulation patterns of the phase modulation elements 54R, 54G, 54B in the plurality of tables stored in the storage unit 76, the phase modulation pattern whose emission direction is different from the reference emission direction is the optical DLR. , The phase modulation pattern is such that light different from DLG and DLB is further emitted from the phase modulation elements 54R, 54G and 54B, respectively. The control unit 71 controls the phase modulation elements 54R, 54G, 54B based on such a plurality of tables, and the vehicle headlight 1 emits light different from the low beam together with the low beam.

FIG. 9 is a diagram showing an example of a state in which the emission direction of the low beam is changed and light different from the low beam is emitted from the vehicle headlight. The state shown in FIG. 9 is a state in which the vehicle is steered to the left as in the state shown in FIG. 8 (B), and in FIG. 9, the state before the emission direction of the low beam is changed is a broken line. It is shown. Further, in FIG. 9, in order to facilitate understanding, the description of the line indicating the boundary between the region LA1 and the region LA2 and the line indicating the boundary between the region LA2 and the region LA3 in the low beam light distribution pattern PL is omitted. There is. In the present embodiment, as shown in FIG. 9, the light different from the low beam does not overlap with the low beam light distribution pattern PL whose emission direction is changed in the low beam light distribution pattern PL before the emission direction is changed AR1, It is irradiated in AR2. In FIG. 9, the areas AR1 and AR2 are hatched diagonally. That is, when the control unit 71 changes the emission direction of the low beam according to the steering angle, the phase modulation elements 54R, 54G, and 54B are modulated so that light different from the low beam is irradiated in the regions AR1 and AR2. Adjust the phase modulation pattern in the unit. Therefore, in the vehicle headlight 1 of the present embodiment, the light is irradiated into the regions AR1 and AR2 in which the light is not irradiated by changing the emission direction of the low beam. Further, in the present embodiment, the brightness of the light emitted to the region AR1 is darker than the brightness of the region AR1 in the low beam light distribution pattern PL before the emission direction is changed. Further, the brightness of the light applied to the region AR2 is darker than the brightness of the region AR2 in the low beam light distribution pattern PL before the emission direction is changed.

As described above, in the vehicle headlight 1 of the present embodiment, the light is irradiated into the regions AR1 and AR2 in which the light is not irradiated by changing the emission direction of the low beam light distribution pattern PL, and the light is irradiated. The brightness of the light emitted into the regions AR1 and AR2 is darker than the brightness of the regions AR1 and AR2 in the low beam light distribution pattern PL before the emission direction is changed. Therefore, in the vehicle headlight 1 of the present embodiment, the driver can recognize the low beam light distribution pattern PL, and the visibility of the regions AR1 and AR2 to which the light is irradiated before changing the emission direction is improved. It is possible to suppress the decrease or the conspicuous areas AR1 and AR2 to be irradiated with light different from the light of the low beam light distribution pattern PL. Therefore, the vehicle headlight 1 of the present embodiment can further suppress the driver from feeling uncomfortable when changing the light emission direction of the low beam light distribution pattern PL.

From the viewpoint that the driver feels uncomfortable when changing the emission direction of the low beam, it is preferable that the light different from the low beam is applied to the entire area AR1 and AR2. Further, the above-mentioned light different from the low beam is preferably emitted when the emission direction of the light DLR, DLG, DLB from the vehicle headlight 1 is changed according to the steering angle of the vehicle, and the inclination angle of the vehicle is preferable. When the emission direction of the optical DLR, DLG, and DLB from the vehicle headlight 1 is changed according to the speed and speed, it is preferable that the light is not emitted.

Further, the brightness of the light applied to the region AR1 does not have to be darker than the brightness of the region AR1 in the low beam light distribution pattern PL before the emission direction is changed. Further, the brightness of the light applied to the region AR2 does not have to be darker than the brightness of the region AR2 in the low beam light distribution pattern PL before the emission direction is changed. Further, the light different from the low beam may be irradiated only to the region AR1 or may be irradiated only to the region AR2. Further, the control unit 71 emits light different from the low beam so that the intensity of the light emitted from the light sources 52R, 52G, 52B is higher than that in the case where the light different from the low beam is not emitted. , 52G, 52B may be controlled. With such a configuration, it is possible to prevent the low beam light distribution pattern PL from being unintentionally darkened as a whole.

(Third Embodiment)
Next, a third embodiment as the first aspect of the present invention will be described in detail with reference to FIG. The same or equivalent components as those in the first embodiment are designated by the same reference numerals and duplicated description will be omitted unless otherwise specified.

FIG. 10 is a diagram showing the optical system unit in the present embodiment in the same manner as in FIG. In addition, in FIG. 10, the description of the heat sink 30, the cover 40, etc. is omitted for ease of understanding. As shown in FIG. 10, the optical system unit 50 of the present embodiment includes one phase modulation element 54S instead of the three phase modulation elements 54R, 54G, 54B, and guides the light guide instead of the synthetic optical system 55. It is mainly different from the optical system unit 50 of the first embodiment in that it includes an optical system 155.

The light guide optical system 155 combines a light LR emitted from the first light emitting optical system 51R, an optical LG emitted from the second light emitting optical system 51G, and an optical LB emitted from the third light emitting optical system 51B into a phase modulation element 54S. Guide to. The light guide optical system 155 of the present embodiment includes a reflection mirror 155 m, a first optical element 155 f, and a second optical element 155 s. The reflection mirror 155m reflects the light LR emitted from the first light emitting optical system 51R. The first optical element 155f transmits the light LR reflected by the reflection mirror 155m and also reflects the light LG emitted from the second light emitting optical system 51G. The second optical element 155s transmits the light LR transmitted through the first optical element 155f and the light LG reflected by the first optical element 155f, and also reflects the light LB emitted from the third light emitting optical system 51B. Examples of such a first optical element 155f and a second optical element 155s include a wavelength selection filter in which an oxide film is laminated on a glass substrate. By controlling the type and thickness of the oxide film, it is possible to transmit light having a wavelength longer than a predetermined wavelength and reflect light having a wavelength shorter than this wavelength.

In the present embodiment, the configuration of the phase modulation element 54S is the same as that of the phase modulation elements 54R, 54G, 54B of the first embodiment. In the present embodiment, the light LR, LG, LB emitted from the light emitting optical system 51R, 51G, 51B is guided to the phase modulation element 54S by the light guide optical system 155 and incident on the phase modulation element 54S. In the present embodiment, the power supplied to the light sources 52R, 52G, 52B is adjusted, laser light is emitted alternately for each of these light sources 52R, 52G, 52B, and laser light is alternately emitted for each of the emission optical systems 51R, 51G, 51B. Optical LR, LG, LB are emitted. That is, when the first light emitting optical system 51R emits the optical LR, the second light emitting optical system 51G and the third light emitting optical system 51B do not emit the optical LG and LB, and the second light emitting optical system 51G emits the optical LG. The first light emitting optical system 51R and the third light emitting optical system 51B do not emit light LR and LB, and the third light emitting optical system 51B emits light LB. The system 51R and the second light emitting optical system 51G do not emit light LR and LG. Then, the emission of the laser beam for each of the light sources 52R, 52G, 52B is sequentially switched, and the emission of the light LR, LG, LB for each of the emission optical systems 51R, 51G, 51B is sequentially switched. That is, the control unit 71 controls the light sources 52R, 52G, and 52B so that the light LR, LG, and LB are emitted in this way. Therefore, the light LR, LG, and LB having different wavelength bands emitted from these emission optical systems 51R, 51G, and 51B are sequentially incident on the phase modulation element 54S. Further, the control unit 71 sets the phase modulation element 54S so that the light DLR, DLG, DLB diffracted by the light LR, LG, LB according to the light LR, LG, LB incident on the phase modulation element 54S is emitted. Control. That is, the phase modulation pattern of the phase modulation unit of the phase modulation element 54S is changed according to the optical LR, LG, and LB incident on the phase modulation element 54S. In FIG. 10, these optical DLRs, DLGs, and DLBs sequentially emitted from the phase modulation element 54S are shown offset.

Next, the emission of light from the phase modulation element 54S of the present embodiment will be described. Specifically, in step SP2, a case where the vehicle headlight 1 emits the light of the low beam light distribution pattern PL without changing the emission direction will be described as an example.

In the present embodiment, the control unit 71 changes the phase modulation pattern of the phase modulation element 54S in synchronization with the switching of the emission of the laser beam for each of the light sources 52R, 52G, 52B as described above. Specifically, when the light LR from the light source 52R is incident, the control unit 71 sets the phase modulation pattern of the phase modulation element 54S to the phase modulation pattern corresponding to the light source 52R, which is the phase modulation element 54S. The first light DLR emitted from the light beam has a phase modulation pattern in which the light is the light of the red component of the light distribution pattern PL of the low beam. Therefore, when the light LR from the light source 52R is incident, the phase modulation element 54S emits the first light DLR, which is the light of the red component of the low beam light distribution pattern PL. Further, when the light LG from the light source 52G is incident, the control unit 71 emits the phase modulation pattern of the phase modulation element 54S from the phase modulation element 54S, which is a phase modulation pattern corresponding to the light source 52G. The second optical DLG has a phase modulation pattern in which the light of the green component of the low beam light distribution pattern PL is used. Therefore, when the light LG from the light source 52G is incident, the phase modulation element 54S emits a second light DLG which is the light of the green component of the low beam light distribution pattern PL. Further, when the light LB from the light source 52B is incident, the control unit 71 emits the phase modulation pattern of the phase modulation element 54S from the phase modulation element 54S, which is a phase modulation pattern corresponding to the light source 52B. The third optical DLB has a phase modulation pattern in which the light of the blue component of the low beam light distribution pattern PL is used. Therefore, when the light LB from the light source 52B is incident, the phase modulation element 54S emits a third light DLB which is the light of the blue component of the low beam light distribution pattern PL.

That is, the control unit 71 changes the phase modulation pattern of the phase modulation element 54S according to the wavelength band of the light LR, LG, and LB incident on the phase modulation element 54S in this way, so that the light of the red component of the low beam can be used. A certain first optical DLR, a second optical DLG which is the light of the green component of the low beam, and a third optical DLB which is the light of the blue component of the low beam are sequentially emitted from the phase modulation element 54S. These optical DLRs, DLGs, and DLBs are emitted from the opening 40H of the cover 40, pass through the imaging lens 81 and the projection lens 82, and are sequentially irradiated to the outside of the vehicle headlight 1 via the front cover 12. .. At this time, the first optical DLR, the second optical DLG, and the third optical DLB are irradiated so that the regions to be irradiated with the respective lights overlap each other at the focal position separated from the vehicle by a predetermined distance. .. This focal position is, for example, a position 25 m away from the vehicle. The first optical DLR, the second optical DLG, and the third optical DLB are irradiated so that the outer shapes of the regions irradiated with the respective optical DLRs, DLGs, and DLBs at this focal position are substantially the same. Is preferable. Further, in the present embodiment, the control unit 71 has substantially the same length of emission time of the laser light emitted from the light sources 52R, 52G, 52B, and the laser emitted from the light sources 52R, 52G, 52B. The light sources 52R, 52G, and 52B are controlled so that the light intensity has the same intensity as that of the first embodiment. Therefore, the lengths of the emission times of the optical DLR, DLG, and DLB are almost the same.

By the way, when light of different colors is repeatedly irradiated with a cycle shorter than the time resolution of human vision, the person can recognize that the light in which the lights of different colors are combined is irradiated by the afterimage effect. In the present embodiment, when the time from the light source 52R emitting the laser beam to the light source 52R emitting the laser beam again is shorter than the time resolution of human vision, it is shorter than the time resolution of human vision. The light DLR, DLG, and DLB emitted from the phase modulation element 54S are repeatedly irradiated with a period, and the red light DLR, the green light DLG, and the blue light DLB are combined by the afterimage effect. As described above, the lengths of the emission times of the optical DLR, DLG, and DLB are substantially the same, and the intensity of the laser light emitted from the light sources 52R, 52G, and 52B is the same as that of the first embodiment. It is said to be strong. Therefore, the color of the light synthesized by the afterimage effect is the same white as the light in which the light DLR, DLG, and DLB are synthesized in the first embodiment. Further, since the light distribution pattern in which the optical DLR, DLG, and DLB are combined is the low beam light distribution pattern PL, the light distribution pattern in which the optical DLR, DLG, and DLB are combined by the afterimage effect is also the low beam. It becomes a light distribution pattern PL. In this way, the light of the low beam light distribution pattern PL is emitted from the vehicle headlight 1.

The period for repeatedly emitting the laser beam from the light sources 52R, 52G, and 52B is preferably 1/15 second or less from the viewpoint of suppressing the flicker of the light synthesized by the afterimage effect. The temporal resolution of human vision is approximately 1/30 second. In the case of a vehicle headlight, if the light emission cycle is about twice, it is possible to suppress the feeling of light flicker. If this period is 1/30 second or less, it generally exceeds the temporal resolution of human vision. Therefore, it is possible to further suppress the feeling of flickering of light. Further, from the viewpoint of further suppressing the feeling of light flicker, this period is preferably 1/60 second or less.

In the vehicle headlight 1 of the present embodiment, the phase modulation element that diffracts the light LR, LG, LB from the three light sources 52R, 52G, 52B can be used as a common phase modulation element, so that the number of parts can be reduced. It can be reduced or downsized.

Although the first aspect of the present invention has been described above by exemplifying the first to third embodiments, the first aspect of the present invention is not limited thereto.

For example, a vehicle headlight as a first aspect of the present invention diffracts a light source and light emitted from this light source with a changeable phase modulation pattern, and has a predetermined light distribution pattern based on the phase modulation pattern. The control unit includes a phase modulation element and a control unit that emits light, and the control unit adjusts the phase modulation pattern and changes the emission direction of light from the phase modulation element while maintaining a predetermined light distribution pattern. Not limited. The vehicle headlight having such a configuration can be made smaller than the vehicle headlight using a shade. In addition, this vehicle headlight can suppress the driver from feeling uncomfortable, and also emits light having a predetermined light distribution pattern according to a change in the traveling direction of the vehicle, an inclination in the pitch direction of the vehicle, or the like. Can be changed and visibility in the direction of travel can be improved.

Further, in the first to third embodiments, the vehicle headlight 1 is supposed to irradiate a low beam, but the vehicle headlight as the first aspect of the present invention is not particularly limited. For example, the vehicle headlight 1 as the first aspect may be irradiated with a high beam, or may be irradiated with light having a light distribution pattern for urban areas suitable for traveling in an urban area. , The light of the light distribution pattern for bad weather suitable for traveling in rainy weather or the like may be irradiated. In such a case, the storage unit 76 stores information about the phase modulation pattern for emitting the light of such a light distribution pattern. In step SP2, the control unit 71 performs phase modulation of the modulation unit of the phase modulation elements 54R, 54G, 54B, 54S so that the light of such a light distribution pattern is emitted based on the information stored in the storage unit 76. Adjust the pattern. Further, the vehicle headlight 1 as the first aspect changes the light distribution pattern of the emitted light from the low beam light distribution pattern to the urban light distribution pattern, the bad weather light distribution pattern, the high beam light distribution pattern, and the like. It may be switchable.

Further, in the first to third embodiments, the phase modulation elements 54R, 54G, 54B, 54S are reflection type phase modulation elements. However, as the phase modulation element, for example, an LCD (Liquid Crystal display) which is a liquid crystal panel, a GLV (Grating Light Valve) in which a plurality of reflectors are formed on a silicon substrate, or the like may be used. The LCD is a transmissive phase modulation element. Similar to LCOS, which is a reflective liquid crystal panel described above, this LCD controls the voltage applied between a pair of electrodes sandwiching a liquid crystal layer at each dot to control the phase of light emitted from each dot. The amount of change can be adjusted to change the light distribution pattern of the emitted light, or to change the direction of the emitted light to change the area irradiated with this light. The pair of electrodes is a transparent electrode. The GLV is a reflection type phase modulation element. By electrically controlling the deflection of the reflector, this GLV diffracts the incident light and emits it, changes the light distribution pattern of the emitted light, and changes the direction of the emitted light. The area to be irradiated can be changed.

Further, in the third embodiment, the light guide optical system 155 includes a reflection mirror 155 m, a first optical element 155 f, and a second optical element 155 s. However, the light guide optical system 155 may guide the light LR, LG, LB emitted from the respective light emission optical systems 51R, 51G, 51B to the phase modulation element 54S, and is not limited to the configuration of the third embodiment. For example, the light guide optical system 155 does not have to include the reflection mirror 155 m. In such a case, the light LR emitted from the first light emitting optical system 51R is incident on the first optical element 155f. Further, in the third embodiment, a bandpass filter that transmits light in a predetermined wavelength band and reflects light in another wavelength band may be used for the first optical element 155f and the second optical element 155s.

Further, in the third embodiment, the optical system unit 50 includes a light guide optical system 155 that guides the light LR, LG, LB emitted from the light emitting optical system 51R, 51G, 51B to the phase modulation element 54S. However, the optical system unit 50 does not have to include the light guide optical system 155. In this case, the emission optical systems 51R, 51G, and 51B are arranged so that the optical LR, LG, and LB are incident on the phase modulation element 54S.

Further, in the first and second embodiments, the first optical element 55f transmits the first optical DLR and reflects the second optical DLG to obtain the first optical DLR and the second optical DLG. The second optical element 55s is combined with the first optical DLR by transmitting the first optical DLR and the second optical DLG synthesized by the first optical element 55f and reflecting the third optical DLB. The second optical DLG and the third optical DLB were synthesized. However, for example, the third optical DLB and the second optical DLG are synthesized in the first optical element 55f, and the third optical DLB and the second optical DLB synthesized by the first optical element 55f in the second optical element 55s. The optical DLG and the first optical DLR may be combined. In this case, in the first and second embodiments, the first light source 52R, the first collimating lens 53R, and the first phase modulation element 54R, the third light source 52B, the third collimating lens 53B, and the third phase modulation element 54B. The positions of and are exchanged. Further, in the first and second embodiments, even if a bandpass filter that transmits light in a predetermined wavelength band and reflects light in another wavelength band is used for the first optical element 55f and the second optical element 55s. good. Further, in the first and second embodiments, the synthetic optical system 55 may synthesize the optical DLRs, DLGs, and DLBs emitted from the respective phase modulation elements 54R, 54G, and 54B, and the configuration of the above embodiment and the above configuration may be sufficient. Not limited to.

Further, in the first and second embodiments, the optical system unit 50 includes a synthetic optical system 55 that synthesizes a first optical DLR, a second optical DLG, and a third optical DLB. However, the optical system unit 50 does not have to include the synthetic optical system 55. In this case, the control unit 71 controls the respective phase modulation elements 54R, 54G, 54B so that the optical DLRs, DLGs, and DLBs emitted from the respective phase modulation elements 54R, 54G, 54B are combined.

Further, in the first and second embodiments, the optical system unit 50 provides a light guide optical system that guides the optical LR, LG, LB emitted from the light emitting optical systems 51R, 51G, 51B to the phase modulation elements 54R, 54G, 54B. I didn't prepare. However, the optical system unit 50 of the first and second embodiments may include a light guide optical system that guides the optical LR, LG, and LB to the phase modulation elements 54R, 54G, and 54B.

Further, in the first to third embodiments, the vehicle headlight 1 includes an imaging lens 81 and a projection lens 82. However, the vehicle headlight 1 does not have to include the imaging lens 81. In such a case, the phase modulation pattern in each of the phase modulation elements 54R, 54G, 54B stored in the storage unit 76 is the optical DLR, DLG, DLB emitted from the phase modulation elements 54R, 54G, 54B, respectively. The phase modulation pattern is such that an image is formed. In step SP2, the control unit 71 has the phase modulation element 54R, so that the optical DLR, DLG, DLB emitted from the phase modulation elements 54R, 54G, 54B are imaged based on the information stored in the storage unit 76. The phase modulation pattern in each of the modulation units of 54G and 54B is adjusted. The positions where the optical DLR, DLG, and DLB are imaged are substantially the same on the optical system unit 50 side of the projection lens 82. The light DLR, DLG, and DLB imaged in this way propagate while diverging after being imaged, and the divergence angle of the optical DLR, DLG, and DLB is adjusted by the projection lens 82, and the divergence angle is adjusted. DLR, DLG, and DLB light is emitted from the vehicle headlight 1 via the front cover 12. Therefore, in such a vehicle headlight 1, the light DLR, DLG, DLB emitted from the phase modulation elements 54R, 54G, 54B is transmitted in the same manner as the vehicle headlight 1 of the first embodiment. The size of the low beam light distribution pattern PL can be easily adjusted as compared with the case where the projection lens is not provided. Further, since the vehicle headlight 1 does not include the imaging lens 81, the number of parts can be reduced as compared with the vehicle headlight 1 of the first embodiment. The vehicle headlight 1 does not have to include the imaging lens 81 and the projection lens 82. However, from the viewpoint of facilitating the adjustment of the size of the light distribution pattern of the emitted light, it is preferable that the vehicle headlight 1 includes a projection lens 82.

Further, in the first and second embodiments, three light sources 52R, 52G, 52B that emit light having different wavelengths from each other, and three phase modulation elements 54R, 54G, which correspond one-to-one to the light sources 52R, 52G, 52B, The optical system unit 50 including the 54B has been described as an example. However, the three phase modulation elements 54R, 54G, 54B may be integrally formed. As a configuration of such a phase modulation element, a configuration in which the phase modulation element is divided into a region corresponding to the light source 52R, a region corresponding to the light source 52G, and a region corresponding to the light source 52B can be mentioned. In such a configuration, the light from the light source 52R is incident on the region corresponding to the light source 52R, the light from the light source 52G is incident on the region corresponding to the light source 52G, and the light from the light source 52B is incident on the region corresponding to the light source 52B. Light is incident. The phase modulation pattern in the region corresponding to the light source 52R is a phase modulation pattern corresponding to the light from the light source 52R, and the phase modulation pattern in the region corresponding to the light source 52G is a phase modulation pattern corresponding to the light from the light source 52G. The phase modulation pattern in the region corresponding to the light source 52B is a phase modulation pattern corresponding to the light from the light source 52B. With such a configuration, the three phase modulation elements 54R, 54G, and 54B are integrally formed, so that the number of parts can be reduced.

Further, in the third embodiment, the three light sources 52R, 52G, 52B alternately emit light for each of the light sources 52R, 52G, 52B. However, from the viewpoint of reducing the number of parts and reducing the size, it is sufficient that at least two light sources emit light alternately for each light source. In this case, the light emitted from the phase modulation element to which the light emitted from at least two light sources is incident is combined by the afterimage effect, and the light synthesized by this afterimage effect and the light emitted from the other phase modulation element are combined. Then, the light of a predetermined light distribution pattern is irradiated.

Further, in the first and second embodiments, the three light sources 52R, 52G, 52B that emit laser light having different wavelength bands and the three phase modulation elements 54R, which correspond one-to-one to the light sources 52R, 52G, 52B, An optical system unit 50 including 54G and 54B has been described as an example. Further, in the third embodiment, an optical system unit 50 including three light sources 52R, 52G, 52B that emit laser beams having different wavelength bands and one phase modulation element 54S has been described as an example. However, the optical system unit may include at least one light source and a phase modulation element corresponding to this light source. For example, the optical system unit may include a light source that emits white laser light and a phase modulation element that diffracts and emits white laser light emitted from this light source. Further, when the optical system unit includes a plurality of light sources and phase modulation elements, it is sufficient that at least one light source corresponds to each phase modulation element. For example, the combined light emitted from a plurality of light sources may be incident on one phase modulation element.

(Fourth Embodiment)
Next, a fourth embodiment as a second aspect of the present invention will be described. The same or equivalent components as those in the first embodiment are designated by the same reference numerals and duplicated description will be omitted unless otherwise specified. The configuration of the vehicle headlight 1 in the fourth embodiment is the same as the configuration of the vehicle headlight 1 in the first embodiment. However, the light distribution pattern of the light emitted by the vehicle headlight 1 of the present embodiment is different from the light distribution pattern of the light emitted by the vehicle headlight 1 of the first embodiment.

Further, as in the first embodiment, the storage unit 76 of the present embodiment contains information on the light distribution pattern formed by the combined light of the light DLR, DLG, DLB emitted from the phase modulation elements 54R, 54G, 54B. A table associated with information indicating the vehicle status is stored. However, although the details will be described later, the vehicle headlight 1 of the present embodiment is configured so that the light distribution pattern of the light emitted according to the steering angle of the vehicle is widened in the left-right direction. Therefore, the storage unit 76 of the present embodiment stores a table in which information on a plurality of light distribution patterns and information on a steering angle as information indicating a vehicle state are associated with each other.

FIG. 11 is a diagram showing a left enlarged light distribution pattern PLL in which the low beam light distribution pattern PL shown in FIG. 6 is expanded to the left side. In FIG. 11, S indicates a horizontal line, and the light distribution pattern is shown by a thick line, and this light distribution pattern is a light distribution pattern formed on a vertical surface 25 m away from the vehicle. Here, the outer shape of the light distribution pattern is defined by, for example, an isointensity line formed by a collection of points at which the intensity of light is a predetermined ratio of the maximum intensity value of light in the light distribution pattern. .. The outer shape of the light distribution pattern of the present embodiment is defined by an isointensity line formed by a group of points whose light intensity is 2.5% of the maximum light intensity value in the light distribution pattern. ..

In FIG. 11, the boundary between the low beam light distribution pattern PL shown in FIG. 6 and the expanded region ARW, which is an expanded region, is shown by a broken line. The width W in the left-right direction of the enlarged region ARW in the left enlarged light distribution pattern PLL is the width in the left-right direction from the left end of the low beam light distribution pattern PL to the left end of the enlarged region ARW. In the present embodiment, the light intensity in the enlarged region ARW is substantially the same as the light intensity in the region LA3 which is the region on the outer peripheral side in the light distribution pattern PL of the low beam. The light intensity in the enlarged region ARW is not particularly limited, and may be higher than the light intensity in the region LA2 in the low beam light distribution pattern PL. Further, in the present embodiment, the light intensity distribution in the region other than the enlarged region ARW in the left enlarged light distribution pattern PLL, that is, the region corresponding to the low beam light distribution pattern PL, is the light intensity in the low beam light distribution pattern PL. Same as distribution. The light intensity distribution in the left enlarged light distribution pattern PLL other than the enlarged region ARW may be different from the light intensity distribution in the low beam light distribution pattern PL.

Next, a table that is information about the light distribution pattern stored in the storage unit 76 of the present embodiment will be described. FIG. 12 is a diagram showing a table in this embodiment. The table TB of the present embodiment is a table in which the phase modulation pattern in the modulation unit of the phase modulation elements 54R, 54G, 54B when forming each light distribution pattern and the information indicating the vehicle state are associated with each other. The phase modulation patterns R0, G0, B0 of the phase modulation elements 54R, 54G, 54B in the table TB are phase modulation patterns when forming the low beam light distribution pattern PL. The phase modulation patterns RL1, GL1, BL1 are phase modulation patterns when the low beam light distribution pattern PL forms a left-expanded light distribution pattern PLL in which the low beam light distribution pattern PL is widened to the left, and the phase modulation patterns RL2, GL2, BL2, and phase modulation Similarly, the patterns RL3, GL3, BL3 ... Are phase modulation patterns when forming the left enlarged light distribution pattern PLL. The width W in the left-right direction of the enlarged region ARW in the left enlarged light distribution pattern PLL formed based on the phase modulation patterns RL1, GL1, BL1 is the narrowest, and the phase modulation patterns RL2, GL2, BL2, and the phase modulation pattern RL3, are the narrowest. The width W becomes wider in the order of GL3, BL3 ... In the table TB of the present embodiment, the order in which the width W of the expansion region ARW in the left expansion light distribution pattern PLL formed is widened with respect to the phase modulation patterns R0, G0, B0 corresponding to the low beam light distribution pattern PL. Then, these phase modulation patterns RL1, GL1, BL1, phase modulation patterns RL2, GL2, BL2 ... Are arranged. On the other hand, the phase modulation patterns RR1, GR1, BR1 are phase modulation patterns when the low beam light distribution pattern PL forms a right-expanded light distribution pattern spread to the right, and the phase modulation patterns RR2, GR2, BR2, and the phase are Similarly, the modulation patterns RR3, GR3, BR3 ... Are phase modulation patterns when forming the right-expanded light distribution pattern. The width W in the left-right direction of the enlarged region ARW in the right enlarged light distribution pattern formed based on the phase modulation patterns RR1, GR1, BR1 is the narrowest, and the phase modulation patterns RR2, GR2, BR2, and the phase modulation patterns RR3, GR3 , BR3 ... The width W becomes wider in this order. In the table TB of the present embodiment, in the order in which the width W of the expansion region ARW in the formed right expansion light distribution pattern is widened with reference to the phase modulation patterns R0, G0, B0 corresponding to the low beam light distribution pattern PL. , These phase modulation patterns RR1, GR1, BR1, phase modulation patterns RR2, GR2, BR2 ... Are arranged.

In the present embodiment, as described above, the information indicating the vehicle state associated with the phase modulation pattern is the steering angle of the vehicle. Specifically, this information is a plurality of ranges related to the steering angle obtained by dividing the range of the steering angle that can be steered in the vehicle into a plurality of parts. Of these ranges, the range θ0 is a continuous range including zero. The plurality of ranges θL1, θL2, θL3 ... Are continuous ranges with respect to the left steering angle, and the plurality of ranges θR1, θR2, θR3 ... Are continuous ranges with respect to the right steering angle, respectively. .. The lower limit of the range θL1 is set to be equal to or greater than the upper limit of the left steering angle in the range θ0, and the upper limit of the range θL1 is set to be less than the lower limit of the left steering angle in the range θL2. Further, the lower limit of the range θL2 is set to be equal to or higher than the upper limit of the left steering angle in the range θL1, and the upper limit of the range θL2 is set to be less than the lower limit of the left steering angle in the range θL3. As described above, the upper limit and the lower limit of each of these ranges increase in the order of range θL1, range θL2, range θL3, and so on. The lower limit of the range θR1 is set to be equal to or greater than the upper limit of the right steering angle in the range θ0, and the upper limit of the range θR1 is set to be less than the lower limit of the right steering angle in the range θR2. Further, the lower limit of the range θR2 is set to be equal to or higher than the upper limit of the right steering angle in the range θR1, and the upper limit of the range θR2 is set to be less than the lower limit of the right steering angle in the range θR3. As described above, the upper limit and the lower limit of each of these ranges increase in the order of range θR1, range θR2, range θR3, and so on. The number of continuous ranges relating to the left steering angle and the number of continuous ranges relating to the right steering angle is not particularly limited.

The range θ0 is associated with phase modulation patterns R0, G0, B0 corresponding to the low beam light distribution pattern PL. A phase modulation pattern corresponding to the left expansion light distribution pattern PLL is associated with each of the ranges θL1, θL2, θL3 ... Left-expanded light distribution pattern PLL formed based on the phase modulation pattern associated with the range θL2 rather than the width W of the enlarged region RAW in the left-enlarged light distribution pattern PLL formed based on the phase modulation pattern associated with the range θL1. The width of the expanded area ARW in is large. Then, the width W of the enlarged region ARW in the left enlarged light distribution pattern PLL formed based on the phase modulation pattern associated with each range becomes wider in the order of the range θL1, the range θL2, the range θL3, and so on. In the present embodiment, 10 sets of phase modulation patterns are associated with each of the ranges θL1, θL2, θL3 ... Specifically, the range θL1 is associated with 10 sets of phase modulation patterns from the phase modulation patterns RL1, GL1, BL1 to the phase modulation patterns RL10, GL10, BL10, and the range θL2 is associated with the phase modulation patterns RL11, GL11. , BL11 to the phase modulation patterns RL20, GL20, BL20, 10 sets of phase modulation patterns are associated.

Each of the ranges θR1, θR2, θR3 ... Is associated with a phase modulation pattern corresponding to the right-enlarged light distribution pattern. Expansion in the right-enlarged light distribution pattern formed based on the phase modulation pattern associated with the range θR2, rather than the width W of the expanded region RAW in the right-enlarged light distribution pattern formed based on the phase modulation pattern associated with the range θR1. The width W of the region ARW is set to be large. Then, in the order of the range θR1, the range θR2, the range θR3, and so on, the width W of the expansion region RAW in the right expansion light distribution pattern formed based on the phase modulation pattern associated with each range becomes wider. In the present embodiment, 10 sets of phase modulation patterns are associated with each of the ranges θR1, θR2, θR3 ... Specifically, the range θR1 is associated with 10 sets of phase modulation patterns from the phase modulation patterns RR1, GR1, BR1 to the phase modulation patterns RR10, GR10, BR10, and the range θL2 is associated with the phase modulation patterns RR11, GR11. , BR11 to the phase modulation patterns RR20, GR20, BR20 are associated with 10 sets of phase modulation patterns. The number of phase modulation patterns associated with the continuous range of the left steering angle and the continuous range of the right steering angle is not particularly limited.

Further, the storage unit 76 also stores information on the intensity of the laser light emitted from the light sources 52R, 52G, 52B, initial values of the steering angle of the vehicle, which is information indicating the vehicle state, reference angles, and the like. The reference angle is an angle that the control unit 71 refers to and rewrites in the control of the vehicle headlight 1 described later, and is an angle corresponding to the steering angle. Therefore, the reference angle includes a right angle and a left angle. The initial value of this reference angle is the initial value of the steering angle. In the present embodiment, the intensity of the laser beam emitted from the light sources 52R, 52G, 52B is set to a predetermined intensity, and the initial value of the steering angle is set to zero.

Next, the operation of the vehicle headlight 1 of the present embodiment will be described. Specifically, an operation of changing the light distribution pattern of the emitted light according to the steering angle of the vehicle will be described. FIG. 13 is a diagram showing an example of a control flowchart of the control unit of the present embodiment.

(Step SP51)
In the present embodiment, first, when the light switch 72 is turned on and a signal instructing the emission of light from the light switch 72 is input to the control unit 71, the control flow of the control unit 71 proceeds to step SP52. On the other hand, if this signal is not input to the control unit 71 in this step, the control flow of the control unit 71 proceeds to step SP56.

(Step SP52)
In this step, the control unit 71 detects the vehicle state. Specifically, the control unit 71 detects the steering angle of the vehicle based on the signal output from the steering sensor 74. Then, the control flow of the control unit 71 proceeds to step SP53.

(Step SP53)
In this step, whether or not the vehicle state has changed based on the steering angle detected in step SP52, the table TB stored in the storage unit 76, and the reference angle stored in the storage unit 76. To judge. Specifically, it is determined whether or not the range including the steering angle detected in step SP52 and the range including the reference angle are the same among the plurality of ranges related to the steering angle in the table TB. When these two ranges are the same, it is assumed that the vehicle state has not changed, and the control flow of the control unit 71 proceeds to step SP54. On the other hand, when these two ranges are different, it is assumed that the vehicle state has changed, and the control flow of the control unit 71 proceeds to step SP55.

(Step SP54)
In this step, the control unit 71 controls the light sources 52R, 52G, 52B and the phase modulation elements 54R, 54G, 54B so that the light distribution pattern of the light emitted from the vehicle headlight 1 is maintained. Specifically, the control unit 71 outputs a predetermined signal to the power supply circuits 61R, 61G, 61B. The power supply circuits 61R, 61G, 61B supply predetermined power from the power supply to the light sources 52R, 52G, 52B based on the signal input from the control unit 71. Therefore, the light sources 52R, 52G, and 52B each emit laser light of a predetermined intensity, and the light LR, LG, and LB of a predetermined intensity emit light from the emission optical systems 51R, 51G, and 51B, respectively. These optical LRs, LGs, and LBs are incident on the corresponding phase modulation elements 54R, 54G, and 54B, respectively. Further, the control unit 71 refers to the table TB stored in the storage unit 76, and the phase of the phase modulation elements 54R, 54G, 54B associated with the range including the reference angle stored in the storage unit 76. The signal based on the modulation pattern is output to the element drive circuits 60R, 60G, 60B. When there are a plurality of phase modulation patterns of the phase modulation elements 54R, 54G, 54B associated with the range including the reference angle, the low beam phase modulation patterns R0, G0, B0 are arranged in the above-mentioned order of the phase modulation patterns. The control unit 71 outputs a signal based on the phase modulation pattern farthest from. For example, when the range including the reference angle is the range θL1, the control unit 71 outputs a signal based on the phase modulation patterns RL10, GL10, and BL10.

The element drive circuits 60R, 60G, 60B adjust the voltage applied to each dot DT of the phase modulation elements 54R, 54G, 54B based on this signal input from the control unit 71, respectively. This voltage is a voltage that makes the phase modulation pattern of the phase modulation elements 54R, 54G, 54B into a phase modulation pattern based on the control unit 71 when the control unit 71 outputs a signal. For example, when the range including the reference angle is the range θL1, this voltage is a voltage that makes the phase modulation pattern of the phase modulation elements 54R, 54G, 54B into the phase modulation patterns RL10, GL10, BL10.

As described above, the optical LR, LG, and LB are incident on the corresponding phase modulation elements 54R, 54G, and 54B, respectively. Therefore, the optical DLR, DLG, DLB based on the phase modulation pattern of the phase modulation elements 54R, 54G, 54B is emitted from the phase modulation elements 54R, 54G, 54B, and the light obtained by synthesizing the optical DLR, DLG, DLB is for a vehicle. Emit from the headlight 1. As described above, the phase modulation pattern is a specific phase modulation pattern associated with the range including the reference angle. Therefore, the light of the light distribution pattern based on the specific phase modulation pattern associated with the range including the reference angle is emitted from the vehicle headlight 1. Then, the control flow of the control unit 71 proceeds to step SP51. Therefore, when it is determined in step SP53 that the vehicle state has not changed, the light of the light distribution pattern based on the specific phase modulation pattern associated with the range including the reference angle stored in the storage unit 76. Continues to emit from the vehicle headlight 1. Therefore, the light distribution pattern of the light emitted from the vehicle headlight 1 is maintained unchanged.

In the present embodiment, the control unit 71 simultaneously controls the phase modulation elements 54R, 54G, 54B and the light sources 52R, 52G, 52B. However, the control unit 71 may sequentially perform these controls. Further, the control unit 71 emits laser light of a predetermined intensity from the light sources 52R, 52G, 52B until the control flow of the control unit 71 proceeds to step SP56 described later.

(Step SP55)
In this step, the control unit 71 sets the light sources 52R, 52G, 52B, and the phase modulation element 54R, so that the light distribution pattern of the light emitted from the vehicle headlight 1 becomes the light distribution pattern according to the vehicle state. Controls 54G and 54B. The control unit 71 emits laser light of a predetermined intensity from the light sources 52R, 52G, 52B in the same manner as in step SP54. Further, the control unit 71 refers to the table TB stored in the storage unit 76, and changes the signal output to the element drive circuits 60R, 60G, 60B at predetermined time intervals to change the phase modulation elements 54R, 54G, 54B. Adjust the phase modulation pattern of. The adjustment of the phase modulation pattern by the control unit 71 will be described according to the relationship between the steering angle detected in step SP52 and the reference angle stored in the storage unit 76.

First, a case where the direction of the steering angle detected in step SP52 and the direction of the reference angle stored in the storage unit 76 are the same will be described. When the range including the steering angle detected in step SP52 or the range including the reference angle is the range θ0 including zero, it is assumed that the direction of the steering angle and the direction of the reference angle are the same. The control unit 71 associates the phase modulation pattern of the phase modulation elements 54R, 54G, 54B with the range including the steering angle detected in step SP52 from the specific phase modulation pattern associated with the range including the reference angle. Up to a specific phase modulation pattern is sequentially changed according to the order of the phase modulation patterns. As described above, the plurality of phase modulation patterns in the table TB are the width W of the enlarged region ARW in the formed light distribution pattern with reference to the phase modulation patterns R0, G0, B0 corresponding to the low beam light distribution pattern PL. Are arranged in the order of widening. Therefore, the light distribution pattern of the light emitted from the vehicle headlight 1 changes sequentially at predetermined time intervals according to the change of the phase modulation pattern, and the expanded region ARW in the light distribution pattern of the emitted light. The width W is gradually widened or narrowed. Then, the light distribution pattern of the emitted light becomes a specific light distribution pattern associated with the range including the steering angle detected in step SP52.

For example, when the range including the reference angle is the range θ0 and the range including the steering angle detected in step SP52 is the range θL2, the control unit 71 phase the phase modulation patterns of the phase modulation elements 54R, 54G, 54B. The modulation patterns R0, G0, B0 are sequentially changed to the phase modulation patterns RL20, GL20, BL20, respectively. In this case, as shown in FIG. 14, the outer shape of the low beam light distribution pattern PL changes so as to continuously spread to the left at predetermined time intervals. Then, the low beam light distribution pattern PL becomes a left enlarged light distribution pattern PLL spread to the left side. That is, the control unit 71 adjusts the phase modulation pattern in each of the modulation units of the phase modulation elements 54R, 54G, 54B according to the steering angle of the vehicle, and continuously changes the outer shape of the low beam light distribution pattern PL. It can be understood that the low beam light distribution pattern PL is set to the left enlarged light distribution pattern PLL spread to the left.

Further, for example, when the range including the reference angle is the range θL2 and the range including the steering angle detected in step SP52 is the range θ0, the control unit 71 has the phase modulation pattern of the phase modulation elements 54R, 54G, 54B. Are sequentially changed from the phase modulation patterns RL20, GL20, BL20 to the phase modulation patterns R0, G0, B0, respectively. In this case, contrary to the case shown in FIG. 14, the width W of the enlarged region ARW of the left enlarged light distribution pattern PLL is continuously narrowed at predetermined time intervals, and the left enlarged light distribution pattern PLL is a low beam light distribution pattern. It becomes PL.

As described above, when the steering angle detected in step SP52 is larger than the reference angle, the light distribution pattern of the light emitted from the vehicle headlight 1 changes so as to continuously spread in the left-right direction, and is detected in step SP52. When the steering angle is smaller than the reference angle, the light distribution pattern of the light emitted from the vehicle headlight 1 continuously changes in the left-right direction. In any case, the light distribution pattern of the light emitted from the vehicle headlight 1 is a light distribution pattern according to the steering angle detected in step SP52.

Next, a case where the direction of the steering angle detected in step SP52 and the direction of the steering angle stored in the storage unit 76 are different will be described. Similar to the above case, the control unit 71 detects the phase modulation pattern of the phase modulation elements 54R, 54G, 54B from the specific phase modulation pattern associated with the range including the reference angle in step SP52. The specific phase modulation pattern associated with the range including is sequentially changed according to the order of the phase modulation patterns. For example, when the range including the reference angle is the range θR1 and the range including the steering angle detected in step SP52 is the range θL1, the control unit 71 phase-modulates the phase modulation pattern of the phase modulation elements 54R, 54G, 54B. The patterns RR10, GR10, BR10 are sequentially changed to the phase modulation patterns RL10, GL10, BL10, respectively. In this case, the width W of the expansion region ARW of the right expansion light distribution pattern is continuously narrowed at predetermined time intervals, the right expansion light distribution pattern becomes the low beam light distribution pattern PL, and the outer shape of the low beam light distribution pattern PL. Changes so that it spreads to the left. Then, the right-enlarged light distribution pattern becomes the left-enlarged light distribution pattern PLL.

As described above, in this step, the control unit 71 adjusts the phase modulation pattern in each of the modulation units of the phase modulation elements 54R, 54G, 54B according to the vehicle state, and emits light from the vehicle headlight 1. The outer shape of the light distribution pattern is continuously changed to obtain another light distribution pattern having a different outer shape from this light distribution pattern. As described above, the control unit 71 detects the vehicle state based on the steering angle of the vehicle. Therefore, it can be understood that the control unit 71 adjusts the phase modulation pattern in each of the modulation units of the phase modulation elements 54R, 54G, and 54B according to the steering angle. Then, the control unit 71 rewrites the reference angle stored in the storage unit 76 to the steering angle detected in step SP52, and the control flow of the control unit 71 proceeds to step SP51.

In this embodiment, similarly to step SP54, the control unit 71 controls the phase modulation elements 54R, 54G, 54B and the light sources 52R, 52G, 52B at the same time. However, the control unit 71 may sequentially perform these controls. Further, the control unit 71 emits laser light of a predetermined intensity from the light sources 52R, 52G, 52B until the control flow of the control unit 71 proceeds to step SP56 described later.

(Step SP56)
In this step, the control unit 71 controls the light sources 52R, 52G, and 52B so that the light from the vehicle headlight 1 is not emitted. Specifically, when the control flow of the control unit 71 proceeds to the step SP56 without inputting the signal instructing the light emission from the light switch 72 to the control unit 71 in the step SP51 as described above, the control unit 71 , The light sources 52R, 52G, 52B are controlled to make the laser light from the light sources 52R, 52G, 52B non-emission. Therefore, the light from the vehicle headlight 1 is not emitted. The control unit 71 rewrites the reference angle stored in the storage unit 76 to the initial value of the steering angle, and the control flow of the control unit 71 proceeds to step SP51.

As described above, in the vehicle headlight 1 of the present embodiment, the outer shape of the low beam light distribution pattern PL is continuously changed according to the steering angle of the vehicle, and the low beam light distribution pattern PL can be expanded in the left-right direction. Make a light distribution pattern. The control flow of the control unit 71 is not particularly limited.

In this embodiment, the inclination detection device 73 and the vehicle speed sensor 75 may not be electrically connected to the control unit 71.

By the way, in the vehicle lighting equipment used as the vehicle headlight described in Patent Document 1, the outer shape of the light distribution pattern changes instantaneously according to the switching of the hologram element. Therefore, the driver may feel uncomfortable when switching the light distribution pattern.

Therefore, the vehicle headlight 1 of the present embodiment includes light sources 52R, 52G, 52B, phase modulation elements 54R, 54G, 54B, and a control unit 71. The phase modulation element 54R diffracts the light emitted from the light source 52R with a changeable phase modulation pattern, and emits an optical DLR having a light distribution pattern based on the phase modulation pattern. The phase modulation element 54G diffracts the light emitted from the light source 52G with a changeable phase modulation pattern, and emits an optical DLG having a light distribution pattern based on the phase modulation pattern. The phase modulation element 54B diffracts the light emitted from the light source 52B with a changeable phase modulation pattern, and emits an optical DLB having a light distribution pattern based on the phase modulation pattern.

In the vehicle headlight 1 of the present embodiment, the control unit 71 adjusts the phase modulation pattern in each of the modulation units of the phase modulation elements 54R, 54G, 54B, and the light distribution pattern emitted from the vehicle headlight 1. The outer shape of is continuously changed to make another light distribution pattern. Therefore, the vehicle headlight 1 of the present embodiment is different from the case where the outer shape of the light distribution pattern changes instantaneously as in the vehicle lighting equipment used as the vehicle headlight described in Patent Document 1. , It is possible to suppress the driver from feeling uncomfortable.

From the viewpoint of suppressing the driver from feeling uncomfortable when changing the outer shape of the light distribution pattern, the control unit 71 has a phase so that the change in the light distribution pattern is recognized as a smooth change in human vision. It is preferable to change the modulation pattern sequentially. That is, the number of light distribution patterns in the table stored in the storage unit 76, the width W of the expanded area RAW in which each light distribution pattern is expanded, and the like are recognized as smooth changes in the light distribution pattern in human vision. It is preferable that the light is generated. Here, the outer shape of the light distribution pattern on the plane passing through the predetermined reference point in the light distribution pattern and the specific portion of the vehicle headlight 1, the straight line passing through the specific portion, the predetermined reference point, and the specific portion. The angle formed by the reference straight line passing through the portion changes according to the change in the outer shape of the light distribution pattern. As a specific portion of the vehicle headlight 1, for example, the center of the projection lens 82 of the vehicle headlight 1 can be mentioned. Further, as a predetermined reference point in the light distribution pattern, for example, a point where the light intensity in the light distribution pattern is maximized can be mentioned. When the amount of change in the outer shape of the light distribution pattern is large, the amount of change in this angle is also large, and when the amount of change in the outer shape of the light distribution pattern is small, the amount of change in this angle is also small. In this way, the amount of change in the outer shape of the light distribution pattern can be expressed by the amount of change in this angle. From the viewpoint of making the change in the light distribution pattern perceived as a smooth change in human vision, the amount of change in this angle when changing the phase modulation pattern is preferably 0.5 ° or less, and 0. It is more preferably 1 ° or less. That is, it is possible to set the number of light distribution patterns in the table stored in the storage unit 76, the width W of the expanded area RAW in which each light distribution pattern is expanded, and the like so that the amount of change in this angle becomes like this. preferable.

Further, in the vehicle headlight 1 of the present embodiment, the control unit 71 adjusts the phase modulation pattern in each of the phase modulation elements 54R, 54G, 54B according to the steering angle of the vehicle, and arranges the low beam. The optical pattern PL is set to a left-enlarged light distribution pattern PLL or a right-enlarged light distribution pattern spread in the left-right direction.

In the vehicle headlight 1 of the present embodiment, the light distribution pattern changes to a left-enlarged light distribution pattern PLL or a right-enlarged light distribution pattern expanded in the left-right direction according to a change in the traveling direction of the vehicle. For example, as shown in FIG. 11, the vehicle headlight 1 of the present embodiment can also irradiate the traveling destination with light on the curved road WR. Therefore, the visibility in the curved road WR can be improved as compared with the case where the light distribution pattern does not change according to the change in the traveling direction of the vehicle.

Further, the vehicle headlight 1 of the present embodiment includes a projection lens 82 through which the light DLR, DLG, DLB emitted from the phase modulation elements 54R, 54G, 54B is transmitted.

Therefore, the vehicle headlight 1 of the present embodiment has a low beam light distribution as compared with the case where the vehicle headlight 1 does not have the projection lens 82 through which the light DLR, DLG, DLB emitted from the phase modulation elements 54R, 54G, 54B is transmitted. The size of the pattern PL can be easily adjusted.

(Fifth Embodiment)
Next, a fifth embodiment as a second aspect of the present invention will be described in detail. The same or equivalent components as those in the fourth embodiment are designated by the same reference numerals and duplicated description will be omitted unless otherwise specified.

The vehicle lighting fixture of the present embodiment is used for automobiles as in the fourth embodiment. Further, the configuration of the vehicle headlight 1 of the present embodiment is the same as that of the vehicle headlight 1 of the fourth embodiment.

FIG. 15 is a block diagram including a vehicle headlight according to the present embodiment. As shown in FIG. 15, a turn switch 77 is electrically connected to the control unit 71 of the present embodiment in place of the inclination detection device 73, the steering sensor 74, and the vehicle speed sensor. The turn switch 77 may be electrically connected to the control unit 71 via an electronic control device of the vehicle. The turn switch 77 is a switch for the driver to select the state of the turn lamp of the vehicle. For example, the turn switch 77 outputs a signal indicating this state when the state in which the left turn lamp blinks is selected, and indicates this state when the state in which the right turn lamp blinks is selected. A signal is output, and when the state in which the left and right turn lamps are not lit is selected, no signal is output.

The table stored in the storage unit 76 of the present embodiment is mainly different from the table TB in the fourth embodiment in that the information indicating the vehicle state is the state of the turn lamp. In the present embodiment, the phase modulation patterns R0, G0, and B0 corresponding to the low beam light distribution pattern PL are associated with the state in which the left and right turn lamps are not lit. The blinking state of the left turn lamp is associated with all of the phase modulation patterns corresponding to the left magnified light distribution pattern PLL. The blinking state of the right turn lamp is associated with all of the right magnified phase modulation patterns. The plurality of phase modulation patterns in the table of the present embodiment are formed with reference to the phase modulation patterns R0, G0, B0 corresponding to the low beam light distribution pattern PL, as in the fourth embodiment. The expanded region ARWs in the pattern are arranged in order of increasing width W.

Further, in the present embodiment, the storage unit 76 also stores the initial state, the reference state, and the like of the turn lamp state, which is information indicating the vehicle state. The reference state is a state in which the control unit 71 refers to and rewrites in the control of the vehicle headlight 1 described later, and is a state corresponding to the state of the turn lamp. The initial state of this reference state is the initial state of the turn lamp state, and the initial state of this turn lamp state is the state in which the left and right turn lamps are not lit.

Next, the operation of the vehicle headlight 1 of the present embodiment will be described. Specifically, an operation of changing the light distribution pattern of the light emitted in response to the signal from the turn switch 77 will be described.

The control flowchart of the control unit 71 of the present embodiment is the same as the control flowchart of the control unit 71 of the fourth embodiment. However, the detection of the vehicle state of the control unit 71 in step SP52 of the present embodiment is different from the detection of the vehicle state of the control unit 71 in the fourth embodiment. Further, the determination of the control unit 71 in step SP53 of the present embodiment is different from the determination of the control unit 71 in the fourth embodiment. Further, the control of the phase modulation elements 54R, 54G, 54B of the control unit 71 in steps SP54, SP55 of the present embodiment is different from the control of the phase modulation elements 54R, 54G, 54B in the fourth embodiment. Therefore, the operation of the vehicle headlight 1 of the present embodiment will be described with reference to FIG.

(Step SP52)
In step SP52 of the present embodiment, the control unit 71 detects the state of the turn lamp based on the signal from the turn switch 77. Then, the control flow of the control unit 71 proceeds to step SP53.

(Step SP53)
In step SP53 of the present embodiment, the control unit 71 determines whether or not the vehicle state has changed based on the state of the turn lamp detected in step SP52 and the reference state stored in the storage unit 76. Specifically, it is determined whether or not the state of the turn lamp detected in step SP52 and the reference state are the same. When the state of the turn lamp detected in step SP52 and the reference state are the same, it is assumed that the vehicle state has not changed, and the control flow of the control unit 71 proceeds to step SP54. When the state of the turn lamp detected in step SP52 and the reference state are different, it is assumed that the vehicle state has changed, and the control flow of the control unit 71 proceeds to step SP55.

(Step SP54)
In step SP54 of the present embodiment, similarly to step SP54 of the fourth embodiment, the control unit 71 has the light sources 52R, 52G, so that the light distribution pattern of the light emitted from the vehicle headlight 1 is maintained. The 52B and the phase modulation elements 54R, 54G, 54B are controlled. The control unit 71 emits a laser beam having a predetermined intensity from the light sources 52R, 52G, 52B. Further, the control unit 71 refers to the table stored in the storage unit 76, and the signal based on the phase modulation pattern of the phase modulation elements 54R, 54G, 54B associated with the reference state stored in the storage unit 76. Is output to the element drive circuits 60R, 60G, 60B. When the left or right turn lamp is blinking in the reference state, the low beam phase modulation patterns R0 and G0 in the above-mentioned order of the phase modulation patterns among the phase modulation patterns associated with the reference state. , The control unit 71 outputs a signal based on the phase modulation pattern farthest from B0. That is, when the reference state is the state in which the left turn lamp blinks in the reference state, the control unit 71 outputs a signal based on the phase modulation pattern corresponding to the left expansion light distribution pattern PLL having the widest width W of the expansion region ARM. do. Further, when the reference state is a state in which the right turn lamp blinks, the control unit 71 outputs a signal based on the phase modulation pattern corresponding to the right expansion light distribution pattern having the widest width W of the expansion region ARW.

Therefore, similarly to the fourth embodiment, the light of the light distribution pattern based on the specific phase modulation pattern associated with the reference state is emitted from the vehicle headlight 1. Then, the control flow of the control unit 71 proceeds to step SP51. Therefore, when it is determined in step SP53 that the vehicle state has not changed, the light of the light distribution pattern based on the specific phase modulation pattern associated with the reference state stored in the storage unit 76 is before the vehicle. Continues to emit from the light 1. Therefore, the light distribution pattern of the light emitted from the vehicle headlight 1 is maintained unchanged.

(Step SP55)
In step SP55 of the present embodiment, similarly to step SP55 of the fourth embodiment, the control unit 71 causes the light distribution pattern of the light emitted from the vehicle headlight 1 to be a light distribution pattern according to the vehicle state. In addition, the light sources 52R, 52G, 52B and the phase modulation elements 54R, 54G, 54B are controlled. The control unit 71 emits a laser beam having a predetermined intensity from the light sources 52R, 52G, 52B. Further, the control unit 71 refers to the table stored in the storage unit 76, changes the signal output to the element drive circuits 60R, 60G, 60B at predetermined time intervals, and changes the signal of the phase modulation element 54R, 54G, 54B. The phase modulation pattern in each modulation section is adjusted. The adjustment of the phase modulation pattern by the control unit 71 will be described according to the relationship between the state of the turn lamp detected in step SP52 and the reference state stored in the storage unit 76.

First, a case where the left or right turn lamp is blinking in the state of the turn lamp detected in step SP52 and the left and right turn lamps are not lit in the reference state will be described. The control unit 71 associates the phase modulation pattern of the phase modulation elements 54R, 54G, 54B with the state of the turn lamp detected in step SP52 from the phase modulation patterns R0, G0, B0 corresponding to the low beam light distribution pattern PL. Up to a specific phase modulation pattern is sequentially changed according to the order of the phase modulation patterns. As described above, the plurality of phase modulation patterns in the table are formed with reference to the phase modulation patterns R0, G0, B0 corresponding to the low beam light distribution pattern PL, as in the first embodiment. The width W of the expansion area ARW in is arranged in the order of increasing width. Therefore, the light distribution pattern of the light emitted from the vehicle headlight 1 changes sequentially at predetermined time intervals according to the change of the phase modulation pattern, and the expanded region ARW in the light distribution pattern of the emitted light. The width W is gradually widened. Then, the light distribution pattern of the emitted light becomes a specific light distribution pattern associated with the state of the turn lamp detected in step SP52.

For example, when the state of the turn lamp detected in step SP52 is a state in which the left turn lamp blinks, the outer shape of the low beam light distribution pattern PL changes so as to continuously spread to the left at predetermined time intervals. Then, the low beam light distribution pattern PL becomes a left enlarged light distribution pattern PLL spread to the left side. On the other hand, when the state of the turn lamp detected in step SP52 is a state in which the right turn lamp blinks, the outer shape of the low beam light distribution pattern PL changes so as to continuously spread to the right at predetermined time intervals. Then, the low beam light distribution pattern PL becomes a right-enlarged light distribution pattern spread to the right.

Next, a case where the state of the turn lamps detected in step SP52 is a state in which the left and right turn lamps are not lit and the reference state is a state in which the left or right turn lamps are blinking will be described. In this case, unlike the above case, the control unit 71 sets the phase modulation pattern of the phase modulation elements 54R, 54G, 54B to the low beam from the specific phase modulation pattern associated with the state of the turn lamp detected in step SP52. The phase modulation patterns R0, G0, and B0 corresponding to the light distribution pattern PL are sequentially changed according to the order of the phase modulation patterns. Therefore, when the reference state is a state in which the left turn lamp blinks, the width W of the expansion region ARW of the left expansion light distribution pattern PLL is continuously narrowed at predetermined time intervals, and the left expansion light distribution pattern PLL has a low beam. Light distribution pattern PL. On the other hand, when the reference state is a state in which the right turn lamp blinks, the width W of the expansion area ARW of the right expansion light distribution pattern is continuously narrowed at predetermined time intervals, and the right expansion light distribution pattern is the low beam light distribution. It becomes a pattern PL.

In this way, in this step, the control unit 71 adjusts the phase modulation pattern in each of the modulation units of the phase modulation elements 54R, 54G, 54B according to the vehicle state, and emits light from the vehicle headlight 1. The outer shape of the light distribution pattern is continuously changed to obtain another light distribution pattern having a different outer shape from this light distribution pattern. As described above, the control unit 71 detects the vehicle state based on the signal output from the turn switch 77. Therefore, it can be understood that the control unit 71 adjusts the phase modulation pattern in each of the modulation units of the phase modulation elements 54R, 54G, 54B according to the signal from the turn switch 77. Then, the control unit 71 rewrites the reference state stored in the storage unit 76 to the state of the turn lamp detected in step SP52, and the control flow of the control unit 71 proceeds to step SP51.

In step SP56 of the present embodiment, the control unit 71 is stored in the storage unit 76 after the light from the vehicle headlight 1 is not emitted in the same manner as in step SP56 of the fourth embodiment. The state is rewritten to the initial state of the turn lamp, and the control flow of the control unit 71 proceeds to step SP51.

In the vehicle headlight 1 of the present embodiment, as described above, the control unit 71 continuously changes the outer shape of the low beam light distribution pattern PL in response to the signal from the turn switch 77, and the low beam light distribution. The pattern PL is set to a light distribution pattern spread in the left-right direction. Therefore, since the vehicle headlight 1 of the present embodiment can also irradiate the traveling destination with light at an intersection or the like, the light distribution pattern does not change according to the signal from the turn switch 77, as compared with the case where the light distribution pattern does not change. Visibility at intersections and the like can be improved.

(Sixth Embodiment)
Next, the sixth embodiment of the present invention will be described in detail. The same or equivalent components as those in the fourth embodiment are designated by the same reference numerals and duplicated description will be omitted unless otherwise specified.

The vehicle lighting fixture of the present embodiment is used for automobiles as in the fourth embodiment. Further, the configuration of the vehicle headlight 1 of the present embodiment is the same as that of the vehicle headlight 1 of the fourth embodiment.

FIG. 16 is a diagram showing a table in this embodiment. As shown in FIG. 16, the table TB of the present embodiment has the phase modulation pattern and the vehicle state in the modulation unit of the phase modulation elements 54R, 54G, 54B when forming each light distribution pattern, as in the fourth embodiment. It is a table associated with the information indicating. The phase modulation patterns R0, G0, B0 of the phase modulation elements 54R, 54G, 54B in the table TB are phase modulation patterns when forming the low beam light distribution pattern PL. The phase modulation patterns RS1, GS1, and BS1 are phase modulation patterns for forming a reduced light distribution pattern in which the outer shape of the low beam light distribution pattern PL is reduced to a substantially similar shape. Similarly, the phase modulation patterns RS2, GS2, BS2, the phase modulation patterns RS3, GS3, BS3 ... It is a modulation pattern. The outer shape of the reduced light distribution pattern formed based on the phase modulation patterns RS1, GS1, BS1 is the largest, and the outer shapes are in the order of the phase modulation pattern RS2, GS2, BS2, the phase modulation pattern RS3, GS3, BS3 ... It gets smaller. The outer shape of the reduced light distribution pattern formed based on the phase modulation patterns RS50, GS50, and BS50 is the smallest. In the table TB of the present embodiment, the phase modulation patterns RS1 are formed in the order in which the outer shape of the reduced light distribution pattern formed is smaller than the phase modulation patterns R0, G0, B0 corresponding to the low beam light distribution pattern PL. , GS1, BS1, phase modulation patterns RS2, GS2, BS2 ... Are arranged. The number of sets of these phase modulation patterns is not particularly limited.

In the present embodiment, the information indicating the vehicle state associated with the phase modulation pattern is the speed of the vehicle. Specifically, this information is a range of the speed of the vehicle, a range in which the speed of the vehicle is less than a predetermined value V1 and a range in which the speed of the vehicle is a predetermined value V1 or more. The phase modulation patterns RS50, GS50, and BS50 corresponding to the reduced light distribution pattern having the smallest outer shape are associated with the range in which the vehicle speed is equal to or higher than the predetermined value V1. In the range where the vehicle speed is less than the predetermined value V1, it corresponds to the phase modulation patterns R0, G0, B0 corresponding to the low beam light distribution pattern PL, and the reduced light distribution pattern other than the reduced light distribution pattern having the smallest outer shape. All of the phase modulation patterns are associated.

Further, the storage unit 76 also stores the initial value of the vehicle speed, the reference speed, and the like, which are information indicating the vehicle state. The reference speed is a speed that the control unit 71 refers to and rewrites in the control of the vehicle headlight 1 described later, and is a speed corresponding to the speed of the vehicle. The initial value of this reference speed is the initial value of the speed of the vehicle, and the initial value of the speed of this vehicle is zero.

Next, the operation of the vehicle headlight 1 of the present embodiment will be described. Specifically, an operation of changing the light distribution pattern of the emitted light based on the speed of the vehicle will be described.

The control flowchart of the control unit 71 of the present embodiment is the same as the control flowchart of the control unit 71 of the fourth embodiment. However, the detection of the vehicle state of the control unit 71 in step SP52 of the present embodiment is different from the detection of the vehicle state of the control unit 71 in the fourth embodiment. Further, the determination of the control unit 71 in step SP53 of the present embodiment is different from the determination of the control unit 71 in the fourth embodiment. Further, the control of the phase modulation elements 54R, 54G, 54B of the control unit 71 in steps SP54, SP55 of the present embodiment is different from the control of the phase modulation elements 54R, 54G, 54B in the fourth embodiment. Therefore, the operation of the vehicle headlight 1 of the present embodiment will be described with reference to FIG.

(Step SP52)
In step SP52 of the present embodiment, the control unit 71 detects the speed of the vehicle based on the signal from the vehicle speed sensor 75. Then, the control flow of the control unit 71 proceeds to step SP53.

(Step SP53)
In this step, whether or not the vehicle state has changed based on the speed detected in step SP52, the table TB stored in the storage unit 76, and the reference speed stored in the storage unit 76. To judge. Specifically, it is determined whether or not the range including the speed detected in step SP52 and the range including the reference speed are the same. When these two ranges are the same, it is assumed that the vehicle state has not changed, and the control flow of the control unit 71 proceeds to step SP54. On the other hand, when these two ranges are different, it is assumed that the vehicle state has changed, and the control flow of the control unit 71 proceeds to step SP55.

(Step SP54)
In step SP54 of the present embodiment, similarly to step SP54 of the fourth embodiment, the control unit 71 has the light sources 52R, 52G, so that the light distribution pattern of the light emitted from the vehicle headlight 1 is maintained. The 52B and the phase modulation elements 54R, 54G, 54B are controlled. The control unit 71 emits a laser beam having a predetermined intensity from the light sources 52R, 52G, 52B. Further, the control unit 71 refers to the table TB stored in the storage unit 76, and the phase of the phase modulation elements 54R, 54G, 54B associated with the range including the reference speed stored in the storage unit 76. The signal based on the modulation pattern is output to the element drive circuits 60R, 60G, 60B. When the reference speed is less than the predetermined value V1, the control unit 71 outputs a signal based on the phase modulation patterns R0, G0, B0 corresponding to the low beam among the phase modulation patterns associated with the range including the reference speed. Output. That is, when the reference speed is less than the predetermined value V1, the control unit 71 outputs a signal based on the phase modulation patterns R0, G0, B0 corresponding to the low beam, and when the reference speed is the predetermined value V1 or more, the outer shape is the most. The control unit 71 outputs a signal based on the phase modulation patterns RS50, GS50, and BS50 corresponding to the small reduced light distribution pattern.

Therefore, similarly to the fourth embodiment, the light of the light distribution pattern based on the specific phase modulation pattern associated with the range including the reference speed is emitted from the vehicle headlight 1. Then, the control flow of the control unit 71 proceeds to step SP51. Therefore, when it is determined in step SP53 that the vehicle state has not changed, the light of the light distribution pattern based on the specific phase modulation pattern associated with the range including the reference speed stored in the storage unit 76. Continues to emit from the vehicle headlight 1. Therefore, the light distribution pattern of the light emitted from the vehicle headlight 1 is maintained unchanged.

(Step SP55)
In step SP55 of the present embodiment, similarly to step SP55 of the fourth embodiment, the control unit 71 causes the light distribution pattern of the light emitted from the vehicle headlight 1 to be a light distribution pattern according to the vehicle state. In addition, the light sources 52R, 52G, 52B and the phase modulation elements 54R, 54G, 54B are controlled. The control unit 71 emits a laser beam having a predetermined intensity from the light sources 52R, 52G, 52B. Further, the control unit 71 refers to the table TB stored in the storage unit 76, and changes the signal output to the element drive circuits 60R, 60G, 60B at predetermined time intervals to change the phase modulation elements 54R, 54G, 54B. The phase modulation pattern in each modulation section of is adjusted. The adjustment of the phase modulation pattern by the control unit 71 will be described according to the relationship between the speed detected in step SP52 and the reference speed stored in the storage unit 76.

First, a case where the speed detected in step SP52 is equal to or higher than the predetermined value V1 and the reference speed is lower than the predetermined value V1 will be described. The control unit 71 performs the phase modulation pattern of the phase modulation elements 54R, 54G, 54B from the phase modulation patterns R0, G0, B0 corresponding to the low beam light distribution pattern PL to the phase modulation patterns RS50, GS50, BS50. Change sequentially according to the order of the patterns. As described above, the plurality of phase modulation patterns in the table TB are in the order in which the outer shapes in the reduced light distribution patterns formed are smaller with respect to the phase modulation patterns R0, G0, B0 corresponding to the low beam light distribution pattern PL. They are lined up at.

Therefore, as shown in FIG. 17, the outer shape of the low beam light distribution pattern PL emitted from the vehicle headlight 1 changes so as to be continuously reduced at predetermined time intervals, and the low beam light distribution pattern PL changes. The reduced light distribution pattern PLS50 is reduced to a substantially similar shape. That is, the control unit 71 adjusts the phase modulation pattern in each of the modulation units of the phase modulation elements 54R, 54G, and 54B, and continuously changes the outer shape of the low beam light distribution pattern PL to obtain the low beam light distribution pattern PL. It can be understood that the reduced light distribution pattern PLS50, which is reduced to a substantially similar shape, is used. In FIG. 17, for ease of understanding, the description of the line indicating the boundary between the region LA1 and the region LA2 and the line indicating the boundary between the region LA2 and the region LA3 in the low beam light distribution pattern PL is omitted. There is. Further, in the present embodiment, the position of the reduced light distribution pattern PLS in which the low beam light distribution pattern PL is reduced to a similar shape is set to a position where the position of the cut-off line CF does not change.

Next, a case where the speed detected in step SP52 is less than the predetermined value V1 and the reference speed is equal to or more than the predetermined value V1 will be described. In this case, unlike the above case, the control unit 71 changes the phase modulation pattern of the phase modulation elements 54R, 54G, 54B from the phase modulation patterns RS50, GS50, BS50 to the phase modulation pattern R0 corresponding to the low beam light distribution pattern PL. , G0, B0 are sequentially changed according to the order of the phase modulation patterns. Therefore, contrary to the case shown in FIG. 17, the outer shape of the reduced light distribution pattern PLS50 emitted from the vehicle headlight 1 changes so as to be continuously increased at predetermined time intervals, and the reduced light distribution pattern PLS50 is changed. Is the low beam light distribution pattern PL.

In this way, the control unit 71 adjusts the phase modulation pattern in each of the modulation units of the phase modulation elements 54R, 54G, 54B according to the detected vehicle state in the step SP55, and from the vehicle headlight 1 The outer shape of the light distribution pattern of the emitted light is continuously changed to obtain another light distribution pattern having a different outer shape from this light distribution pattern. As described above, the control unit 71 detects the vehicle state based on the speed of the vehicle. Therefore, it can be understood that the control unit 71 adjusts the phase modulation pattern in each of the modulation units of the phase modulation elements 54R, 54G, and 54B based on the speed of the vehicle. Then, the control unit 71 rewrites the reference speed stored in the storage unit 76 to the speed detected in step SP52, and the control flow of the control unit 71 proceeds to step SP51.

In step SP56 of the present embodiment, the control unit 71 is stored in the storage unit 76 after the light from the vehicle headlight 1 is not emitted in the same manner as in step SP56 of the fourth embodiment. The speed is rewritten to the initial value, and the control flow of the control unit 71 proceeds to step SP51.

In this embodiment, the tilt detection device 73 and the steering sensor 74 may not be electrically connected to the control unit 71.

In the vehicle headlight 1 of the present embodiment, as described above, the control unit 71 performs phase modulation in each of the phase modulation elements 54R, 54G, 54B when the vehicle speed becomes a predetermined value V1 or more. The pattern is adjusted to continuously change the outer shape of the low beam light distribution pattern PL so that the low beam light distribution pattern PL is a reduced light distribution pattern PLS 50 smaller than the low beam light distribution pattern PL. Vehicle headlights tend to require distant visibility when traveling at high speeds than when traveling normally. The vehicle headlight 1 of the present embodiment can emit the light of the reduced light distribution pattern PLS 50, which is smaller than the low beam light distribution pattern PL, when traveling at high speed. Therefore, the driver's line of sight can be easily concentrated in the vicinity of the central portion in front of the vehicle as compared with the case where the low beam is emitted during high-speed driving, and the visibility in the distance can be improved. Further, in the vehicle headlight 1 of the present embodiment, the control unit 71 performs phase modulation in each modulation unit of the phase modulation elements 54R, 54G, 54B in a specific case where the vehicle speed is equal to or higher than a predetermined value V1. Adjust the pattern. Therefore, it is possible to suppress an increase in the calculation load of the control unit 71. Further, in the vehicle headlight 1 of the present embodiment, the outer shape of the reduced light distribution pattern PLS50, which is smaller than the low beam light distribution pattern PL, is substantially similar to the outer shape of the low beam light distribution pattern PL. Therefore, it is possible to further suppress the driver's feeling of discomfort as compared with the case where the outer shape of the reduced light distribution pattern PLS50, which is smaller than the low beam light distribution pattern PL, is not substantially similar to the outer shape of the low beam light distribution pattern PL. .. The outer shape of the reduced light distribution pattern PLS50S, which is smaller than the low beam light distribution pattern PL, does not have to be similar to the outer shape of the low beam light distribution pattern PL.

From the viewpoint of improving visibility during high-speed driving, the control unit 71 adjusts the phase modulation pattern in each modulation unit of the phase modulation elements 54R, 54G, 54B according to the speed of the vehicle, and the light distribution pattern. The outer shape of the light distribution pattern may be continuously changed to make the light distribution pattern smaller than the light distribution pattern. Specifically, the control unit 71 has a phase in each of the modulation units 54R, 54G, 54B so that the light distribution pattern of the emitted light becomes a smaller light distribution pattern as the speed of the vehicle increases. The modulation pattern may be adjusted. As such a configuration, there is a configuration in which the range of the speed of the vehicle associated with the phase modulation pattern in the table TB is three or more. Even with such a configuration, light having a light distribution pattern smaller than that of the low beam light distribution pattern PL can be emitted during high-speed traveling. Therefore, the driver's line of sight can be easily concentrated in the vicinity of the central portion in front of the vehicle as compared with the case where the low beam is emitted during high-speed driving, and the visibility in the distance can be improved. Further, with such a configuration, the light distribution pattern to be emitted can be reduced according to the speed of the vehicle, so that it is possible to further suppress the driver from feeling uncomfortable.

The second aspect of the present invention has been described with reference to the fourth to sixth embodiments as examples, but the second aspect of the present invention is not limited thereto.

For example, a vehicle headlight as a second aspect of the present invention diffracts a light source and light emitted from this light source with a changeable phase modulation pattern, and has a predetermined light distribution pattern based on the phase modulation pattern. The control unit includes a phase modulation element and a control unit that emits light, and the control unit adjusts the phase modulation pattern and continuously changes the outer shape of the predetermined light distribution pattern so that the outer shape of the light distribution pattern is different from that of the predetermined light distribution pattern. As long as it is a pattern, it is not particularly limited. The vehicle headlight having such a configuration can suppress the driver from feeling uncomfortable as compared with the case where the outer shape of the light distribution pattern changes instantaneously.

Further, in the fourth to sixth embodiments, the vehicle headlight 1 is supposed to irradiate a low beam, but the vehicle headlight as the second aspect of the present invention is not particularly limited. Similar to the first aspect, for example, the vehicle headlight 1 of the second aspect may emit a high beam, and irradiates light with a light distribution pattern for an urban area suitable for traveling in an urban area. It may be used to irradiate light with a light distribution pattern for bad weather suitable for traveling in rainy weather or the like. That is, the control unit 71 adjusts the phase modulation pattern of the modulation unit of the phase modulation elements 54R, 54G, 54B, 54S so that the light of such a light distribution pattern is emitted. Further, the vehicle headlight 1 can switch the light distribution pattern of the emitted light from the low beam light distribution pattern PL to the urban light distribution pattern, the bad weather light distribution pattern, the high beam light distribution pattern, and the like. Is also good. In this case, as in the fourth to sixth embodiments, the control unit adjusts the phase modulation pattern, continuously changes the outer shape of the light distribution pattern of the emitted light, and sets the low beam light distribution pattern PL in the urban area. It may be changed to a light distribution pattern for use, a light distribution pattern for bad weather, or the like.

Further, in the 4th to 6th embodiments, the phase modulation elements 54R, 54G, 54B, 54S are reflection type phase modulation elements. However, as the phase modulation element, for example, LCD, GLV, or the like may be used.

Further, the vehicle headlight as the second aspect may have the same configuration as the vehicle headlight 1 of the third embodiment shown in FIG. That is, the optical system unit 50 may be configured to include three light sources 52R, 52G, 52B that emit laser light having different wavelength bands, one phase modulation element 54S, and a light guide optical system 155. .. In this case, the three light sources 52R, 52G, 52B alternately emit light for each of these light sources 52R, 52G, 52B, and the phase modulation element 54S switches the emission of light for each of the light sources 52R, 52G, 52B. Change the phase modulation pattern in synchronization with. Even in such a vehicle headlight, as described above, by synthesizing the light DLR, DLG, and DLB emitted from the phase modulation element 54S by the afterimage effect, for example, the light of the low beam light distribution pattern PL is used. Can be emitted. In such a vehicle headlight, the phase modulation element that diffracts the light LR, LG, LB from the three light sources 52R, 52G, 52B can be used as a common phase modulation element, so that the number of parts can be reduced. It can be reduced or downsized.

Further, in the fourth to sixth embodiments, the first optical element 55f transmits the first optical DLR and reflects the second optical DLG to obtain the first optical DLR and the second optical DLG. The second optical element 55s is combined with the first optical DLR by transmitting the first optical DLR and the second optical DLG synthesized by the first optical element 55f and reflecting the third optical DLB. The second optical DLG and the third optical DLB were synthesized. However, as in the first aspect, for example, the third optical DLB and the second optical DLG are synthesized in the first optical element 55f, and the second optical element 55s is synthesized by the first optical element 55f. The configuration may be such that the optical DLB of 3 and the second optical DLG and the first optical DLR are combined. Further, in the fourth to sixth embodiments, even if a bandpass filter that transmits light in a predetermined wavelength band and reflects light in another wavelength band is used for the first optical element 55f and the second optical element 55s. good. Further, in the fourth to sixth embodiments, the synthetic optical system 55 may synthesize the optical DLRs, DLGs, and DLBs emitted from the respective phase modulation elements 54R, 54G, and 54B, and the synthetic optical system 55 may synthesize the optical DLRs, DLGs, and DLBs of the fourth to sixth embodiments. It is not limited to the configuration and the above configuration.

Further, in the fourth to sixth embodiments, the optical system unit 50 includes a synthetic optical system 55 that synthesizes a first optical DLR, a second optical DLG, and a third optical DLB. However, as in the first aspect, the optical system unit 50 of the second aspect does not have to include the synthetic optical system 55.

Further, in the fourth to sixth embodiments, the optical system unit 50 provides a light guide optical system that guides the optical LR, LG, LB emitted from the light emitting optical systems 51R, 51G, 51B to the phase modulation elements 54R, 54G, 54B. I didn't prepare. However, as in the first aspect, even if the optical system unit 50 of the fourth to sixth embodiments includes a light guide optical system that guides the optical LR, LG, LB to the phase modulation elements 54R, 54G, 54B. good.

Further, in the fourth to sixth embodiments, the vehicle headlight 1 includes an imaging lens 81 and a projection lens 82. However, as in the first aspect, the vehicle headlight 1 of the second aspect does not have to include the imaging lens 81. Further, as in the first aspect, the vehicle headlight 1 of the second aspect may not include the imaging lens 81 and the projection lens 82.

Further, in the fourth to sixth embodiments, the control unit 71 controls the phase modulation elements 54R, 54G, 54B based on the information regarding the phase modulation pattern in the table stored in the storage unit 76. However, the control unit 71 calculates a phase modulation pattern based on a signal from the steering sensor 74, a signal from the vehicle speed sensor 75, a signal from the turn switch 77, and the like, and the phase is calculated based on the calculated phase modulation pattern. The modulation elements 54R, 54G, 54B may be controlled.

Further, in the fourth to sixth embodiments, the intensity of the laser beam emitted from the light sources 52R, 52G, 52B is set to a predetermined intensity. However, the control unit 71 may change the intensity of the laser beam emitted from the light sources 52R, 52G, 52B according to the change in the phase modulation pattern of the phase modulation elements 54R, 54G, 54B. That is, the control unit 71 may adjust the intensity of the laser light emitted from the light sources 52R, 52G, 52B according to the light distribution pattern of the light DLR, DLG, DLB emitted from the phase modulation elements 54R, 54G, 54B. .. With such a configuration, it is possible to prevent the light distribution pattern of the emitted light from being unintentionally darkened or brightened as a whole.

Further, in the vehicle headlight 1 of the fourth embodiment, the outer shape of the light distribution pattern emitted changes according to the steering angle of the vehicle, and in the vehicle headlight 1 of the fifth embodiment, the signal from the turn switch 77. The outer shape of the light distribution pattern emitted was changed accordingly, and the outer shape of the light distribution pattern emitted was changed in the vehicle headlight 1 according to the sixth embodiment based on the speed of the vehicle. However, the vehicle headlight of the second aspect of the present invention may be a combination of these vehicle headlights 1. For example, the control unit of the vehicle headlight adjusts the phase modulation pattern according to the steering angle of the vehicle to change the light distribution pattern of the emitted light, and the phase is changed according to the signal from the turn switch 77 of the vehicle. The outer shape of the light distribution pattern may be changed by adjusting the modulation pattern. In this case, for example, the control unit may change the outer shape of the light distribution pattern by giving priority to the signal from the turn switch 77 of the vehicle over the steering angle of the vehicle.

Further, in the fourth to sixth embodiments, three light sources 52R, 52G, 52B that emit light having different wavelengths from each other, and three phase modulation elements 54R, 54G, which correspond one-to-one to the light sources 52R, 52G, 52B, The optical system unit 50 including the 54B has been described as an example. However, as in the first aspect, the three phase modulation elements 54R, 54G, 54B may be integrally formed.

Further, in the fourth to sixth embodiments, three light sources 52R, 52G, 52B that emit laser light having different wavelength bands and three phase modulation elements 54R, which correspond one-to-one to the light sources 52R, 52G, 52B, An optical system unit 50 including 54G and 54B has been described as an example. However, as in the first aspect, the optical system unit of the second aspect may include at least one light source and a phase modulation element corresponding to this light source. For example, the optical system unit may include a light source that emits white laser light and a phase modulation element that diffracts and emits white laser light emitted from this light source. Further, when the optical system unit includes a plurality of light sources and phase modulation elements, it is sufficient that at least one light source corresponds to each phase modulation element. For example, the combined light emitted from a plurality of light sources may be incident on one phase modulation element.

(7th Embodiment)
Next, a seventh embodiment as a third aspect of the present invention will be described. The same or similar components as those in the first embodiment are designated by the same reference numerals and duplicated description will be omitted unless otherwise specified.

FIG. 18 is a diagram showing a vehicle lamp according to the present embodiment, and is a diagram schematically showing a vertical cross section of the vehicle lamp in the vertical direction. The vehicle lighting fixture of the present embodiment is a vehicle headlight 1. As shown in FIG. 18, the vehicle headlight 1 of the present embodiment is mainly different from the vehicle headlight 1 of the first embodiment in that it does not include the imaging lens 81 and the projection lens 82.

FIG. 19 is an enlarged view of the optical system unit 50 of the present embodiment shown in FIG. In FIG. 19, the heat sink 30, the cover 40, and the like are not shown for ease of understanding. As shown in FIG. 19, the optical system unit 50 of the present embodiment includes a first light source 52R, a second light source 52G, a third light source 52B, a first phase modulation element 54R, and a second phase modulation element 54G. , A third phase modulation element 54B, a synthetic optical system 55, a first light source element 83R, a second light source element 83G, and a third light source element 83B are provided as main configurations.

As shown in FIG. 19, in the present embodiment, the first light source 52R emits a laser beam having a red component having a power peak wavelength of, for example, 638 nm downward. The second light source 52G emits a laser beam having a green component having a power peak wavelength of, for example, 515 nm forward, and the third light source 52B emits a laser beam having a blue component having a power peak wavelength of, for example, 445 nm rearward. In the present embodiment, power is supplied to the light sources 52R, 52G, and 52B by the control unit 71. These light sources 52R, 52G, and 52B are fixed to the cover 40 by a configuration (not shown).

A first collimating lens 53R is arranged below the first light source 52R. A second collimating lens 53G is arranged in front of the second light source 52G. A third collimating lens 53B is arranged behind the third light source 52B. These collimating lenses 53R, 53G, and 53B are fixed to the cover 40 by a configuration (not shown), and can collimate the fast axis direction and the slow axis direction of the laser beam.

By separately providing a collimating lens that collimates the fast axis direction of the laser beam and a collimating lens that collimates the slow axis direction, the fast axis direction and the slow axis direction of the laser beam may be collimated.

The first phase modulation element 54R is arranged below the first collimating lens 53R in a state of being tilted by approximately 45 ° with respect to the front-rear direction and the vertical direction. The second phase modulation element 54G is arranged in front of the second collimating lens 53G in a state of being inclined by approximately 45 ° in the direction opposite to the first phase modulation element 54R with respect to the front-rear direction and the vertical direction. The third phase modulation element 54B is arranged behind the third collimating lens 53B in a state of being inclined at approximately 45 ° in the same direction as the first phase modulation element 54R with respect to the front-rear direction and the vertical direction. In the present embodiment, each of the phase modulation elements 54R, 54G, and 54B is a reflection type phase modulation element that diffracts light incident from the front surface and emits the light from the front surface. It is called LCOS.

The first light receiving element 83R is arranged diagonally above the front of the first phase modulation element 54R. In the present embodiment, the first light receiving element 83R is fixed to the cover 40 in a state facing the first phase modulation element 54R by a configuration (not shown). FIG. 20 is a front view schematically showing the first light receiving element 83R. As shown in FIG. 20, the first light receiving element 83R has a light receiving surface 83Rf. The first light receiving element 83R is a light amount sensor that converts the amount of light incident on the light receiving surface 83Rf into an electric signal and outputs it to the control unit 71, and is, for example, a photodiode.

As shown in FIG. 19, the second light receiving element 83G and the third light receiving element 83B are arranged diagonally above the rear of the second phase modulation element 54G and diagonally above the front of the third phase modulation element 54B, respectively. These light receiving elements 83G and 83B are fixed to the cover 40 by a configuration (not shown) in a state of facing the phase modulation elements 54G and 54B, respectively. These light receiving elements 83G and 83B also have a light receiving surface like the first light receiving element 83R. The light receiving elements 83G and 83B are light amount sensors that convert the amount of light incident on these light receiving surfaces into electric signals and output them to the control unit 71, and are, for example, photodiodes.

The synthetic optical system 55 includes a first optical element 55f and a second optical element 55s. The first optical element 55f is arranged in front of the first phase modulation element 54R and above the second phase modulation element 54G, and is tilted by approximately 45 ° in the direction opposite to the first phase modulation element 54R in the front-rear direction and the vertical direction. It is placed in a state of being. The first optical element 55f is, for example, a wavelength selection filter in which an oxide film is laminated on a glass substrate, transmits light having a wavelength longer than a predetermined wavelength, and reflects light having a wavelength shorter than the predetermined wavelength. The type and thickness of the oxide film are adjusted as described above. In the present embodiment, the first optical element 55f is configured to transmit the light of the red component emitted from the first light source 52R and to reflect the light of the green component emitted from the second light source 52G.

The second optical element 55s is arranged in front of the first optical element 55f and above the third phase modulation element 54B, and is tilted by approximately 45 ° in the direction opposite to the first phase modulation element 54R in the front-rear direction and the vertical direction. Arranged in the state. The second optical element 55s is a wavelength selection filter like the first optical element 55f. In the present embodiment, the second optical element 55s transmits the light of the red component emitted from the first light source 52R and the light of the green component emitted from the second light source 52G, and the light of the blue component emitted from the third light source 52B. Is configured to reflect.

Next, the functional configuration of the vehicle headlight 1 will be described in more detail.

FIG. 21 is a block diagram including the vehicle headlight 1 shown in FIG. As shown in FIG. 21, the vehicle headlight 1 in the present embodiment is connected to the control unit 71, the element drive circuit 60R connected to the first phase modulation element 54R, and the second phase modulation element 54G. The element drive circuit 60G, the element drive circuit 60B connected to the third phase modulation element 54B, the power supply circuit 59 connected to the light sources 52R, 52G, 52B, the storage unit 76, the warning unit drive circuit 78, and the warning. Part 79 and.

The element drive circuits 60R, 60G, 60B are connected to the control unit 71, and a predetermined voltage is applied to the phase modulation elements 54R, 54G, 54B based on the signal output from the control unit 71. As a result, the refractive index of the liquid crystal layer 66 in each dot DT of the phase modulation elements 54R, 54G, 54B is adjusted. By adjusting the refractive index of each dot DT in this way, each of the optical DLR, DLG, and DLB emitted from the phase modulation elements 54R, 54G, and 54B can have a predetermined light distribution pattern such as a low beam. .. Further, by adjusting the refractive index in each dot DT in this way, the optical paths of the optical DLR, DLG, and DLB are transmitted from the phase modulation elements 54R, 54G, and 54B in a state where the predetermined light distribution pattern is maintained. It may be an optical path toward the opening 40H, or an optical path from the phase modulation elements 54R, 54G, 54B toward the light receiving elements 83R, 83G, 83B.

The power supply circuit 59 is connected to the light sources 52R, 52G, 52B and the control unit 71. When a signal for turning on the light sources 52R, 52G, 52B is input to the control unit 71, the control unit 71 controls the power supply circuit 59, and the power supply circuit 59 sends the power corresponding to the signal to the light sources 52R, 52G, 52B. To supply.

The storage unit 76 of the present embodiment stores reference value data for detecting a defect in the phase modulation elements 54R, 54G, 54B. In the present embodiment, this reference value data is obtained in advance as a voltage value generated in each light receiving element 83R, 83G, 83B in a state where the phase modulation elements 54R, 54G, 54B are not defective. When a signal is input from the control unit 71, the storage unit 76 outputs this reference value data to the control unit 71.

The warning unit drive circuit 78 is connected to the control unit 71 and the warning unit 79. When a predetermined drive signal is input to the control unit 71, the control unit 71 applies a predetermined voltage to the warning unit 79 via the warning unit drive circuit 78.

The warning unit 79 is, for example, a light emitting element such as a light emitting diode that emits light by the voltage applied by the control unit 71. The warning unit 79 is incorporated in, for example, a combination meter of a vehicle, and when the warning unit 79 operates, a predetermined portion of the combination meter emits light. The warning unit 79 does not have to be a light emitting element, and may be configured to make the driver or the like know that the warning unit 79 is operating. For example, it may be a sounding element that sounds by the voltage applied from the warning unit drive circuit 78, or may be configured to include both a light emitting element and a sounding element.

Next, the emission of light in the vehicle headlight 1 will be described by taking the case where a low beam is emitted from the vehicle headlight 1 as an example.

When a signal with a light switch (not shown) turned on is input to the control unit 71 via, for example, an electronic control unit (ECU) of a vehicle, the control unit 71 supplies electric power from the power supply circuit 59 to the light sources 52R, 52G, 52B. Supply. As a result, red laser light is generated from the first light source 52R, green laser light is generated from the second light source 52G, and blue laser light is generated from the third light source 52B.

As shown in FIG. 19, the red laser beam is emitted downward and is collimated by the first collimating lens 53R. Further, the green laser beam is emitted forward and is collimated by the second collimating lens 53G. Further, the blue laser light is emitted backward and is collimated by the third collimating lens 53B.

The control unit 71 controls the element drive circuit 60R to apply a predetermined voltage from the element drive circuit 60R to the phase modulation element 54R. By this voltage, the refractive index of each dot DT of the phase modulation element 54R is changed so that the light distribution pattern of the light emitted from the phase modulation element 54R becomes the low beam light distribution pattern. When the collimated red laser beam propagates downward and enters the phase modulation element 54R, it is diffracted and reflected by the phase modulation element 54R to become the first optical DLR having a low beam light distribution pattern. .. This optical DLR is emitted forward from the phase modulation element 54R.

The collimated green laser light and blue laser light propagate forward and backward, respectively, and enter the phase modulation elements 54G and 54B, respectively. Similar to the red laser light, the green laser light and the blue laser light are diffracted and reflected by the phase modulation elements 54G and 54B to which a predetermined voltage is applied, so that the light DLG has a low beam light distribution pattern. It becomes DLB. These optical DLGs and DLBs are emitted upward from the phase modulation elements 54G and 54B, respectively.

As described above, the first optical DLR, which is the light of the red component, passes through the first optical element 55f arranged in front of the phase modulation element 54R. Further, the second optical DLG, which is the light of the green component, is reflected by the first optical element 55f arranged above the phase modulation element 54G as described above. Therefore, the second optical DLG turns 90 degrees at the first optical element 55f and propagates forward. As a result, the first synthetic light LS1 composed of the light DLR and DLG propagates forward.

As described above, the second optical element 55s arranged in front of the first optical element 55f transmits the light of the red component and the light of the green component. Therefore, the first synthetic light LS1 passes through the second optical element 55s. Further, the third optical DLB, which is the light of the blue component, is reflected by the second optical element 55s arranged above the phase modulation element 54B as described above. Therefore, the third optical DLB turns 90 degrees at the second optical element 55s and propagates forward. As a result, the second synthetic light LS2 composed of optical DLR, DLG, and DLB propagates forward.

As described above, the optical DLRs, DLGs, and DLBs that form the second synthetic light all have a light distribution pattern that is a low beam light distribution pattern. Therefore, when the second synthetic light LS2 emitted from the opening 40H propagates forward by a predetermined distance, the optical DLRs, DLGs, and DLBs overlap each other, and the low beam light distribution pattern PL, which is white light as shown in FIG. Can be formed. In FIG. 22, the light distribution pattern is shown by a thick line, and the straight line S shows a horizontal line. Further, the region PLA1 is a region having the highest light intensity, and the light intensity decreases in the order of the region PLA2 and the region PLA3.

Hereinafter, in the present specification, the optical path of the optical path DLR, DLG, DLB emitted from the phase modulation elements 54R, 54G, 54B to the outside of the vehicle headlight 1 through the opening 40H may be referred to as a standard optical path OPS. Further, in the present specification, a state in which a voltage is applied to the phase modulation elements 54R, 54G, 54B so that the optical DLR, DLG, and DLB propagate through the standard optical path OPS to form a low beam light distribution pattern PL is described. Sometimes called standard mode.

In the present embodiment, the control unit 71 changes the voltage applied to the phase modulation elements 54R, 54G, 54B to a voltage different from the voltage in the standard mode at a predetermined timing. Hereinafter, a state in which a voltage different from the standard mode is applied to the phase modulation elements 54R, 54G, 54B may be referred to as a detection mode. In the present embodiment, the optical paths of the optical DLR, DLG, and DLB are changed from the standard optical path OPS in a state where the low beam light distribution pattern PL is maintained by switching the vehicle headlight 1 from the standard mode to the detection mode. It is deflected from the phase modulation elements 54R, 54G, 54B to the detection optical path OPE toward the light receiving elements 83R, 83G, 83B. As a result, the optical DLR, DLG, and DLB are incident on the light receiving elements 83R, 83G, and 83B, and a signal based on the incident light amount is input to the control unit 71. The control unit 71 detects a defect in the phase modulation elements 54R, 54G, 54B based on this signal. In the present embodiment, such a detection process is executed for a predetermined period after the emission of light from the light sources 52R, 52G, 52B is started. The predetermined period may be 1/30 second or less. Hereinafter, this detection process will be described in more detail.

In the present embodiment, when the phase modulation element 54R is set to the detection mode in a state where there is no defect, the optical DLR is an incident spot inside the light receiving surface 83Rf of the light receiving element 83R, as shown by the solid circle in FIG. It is incident on the light receiving element 83R so that the entire Sr is located. Similarly, when the phase modulation elements 54G and 54B are set to the detection mode without any malfunction, the optical DLG and DLB receive light elements so that the entire incident spot is located inside the light receiving surface of the light receiving elements 83G and 83B. It is incident on 83G and 83B. In FIG. 20, the shape of the incident spot Sr is shown as a circle in order to avoid complicating the figure, but the actual shape of the incident spot Sr is not always circular.

FIG. 23 is a diagram showing an example of a flowchart showing control of the detection process by the control unit 71 in the present embodiment. As shown in FIG. 23, the detection process in this embodiment includes steps SP11 to SP15.

(Step SP11)
In this embodiment, the control unit 71 operates when the ACC power supply (accessory power supply) of the vehicle is turned on. Therefore, the time when the ACC power is turned on is the start of FIG. 23. First, when the above-mentioned light switch is turned on, a signal that the light switch is turned on is input to the control unit 71 via the above-mentioned ECU. In this case, the control unit 71 determines that the light switch is on, and advances the detection process to step SP12. On the other hand, when the signal that the light switch is turned on is not input to the control unit 71, the control unit 71 repeats step SP11. Hereinafter, the term "judgment" as used herein means that the control unit 71 changes the next step of the detection process by classifying cases according to the signal input in this way.

(Step SP12)
As described above, when the signal with the light switch turned on is input to the control unit 71, the control unit 71 controls the power supply circuit 59 to supply power from the power supply circuit 59 to the light sources 52R, 52G, 52B. As a result, light emission from the light sources 52R, 52G, and 52B is started. When a signal with the light switch turned on is input to the control unit 71, the control unit 71 controls the element drive circuits 60R, 60G, 60B, and the phase modulation element 54R, from the element drive circuits 60R, 60G, 60B, A predetermined voltage is applied to 54B and 54G. This voltage is different from the standard mode, and the voltage causes the vehicle headlight 1 to enter the detection mode. In this way, the optical paths of the optical DLR, DLG, and DLB are designated as the detection optical path OPE.

(Step SP13)
When the vehicle headlight 1 is set to the detection mode, the optical DLR, DLG, and DLB are incident on the light receiving elements 83R, 83G, and 83B. As described above, when the phase modulation elements 54R, 54G, and 54B are not defective, the entire incident spots of the optical DLR, DLG, and DLB are located inside the light receiving surface of the light receiving elements 83R, 83B, and 83G, respectively. do. Therefore, when the phase modulation elements 54R, 54G, and 54B are not defective, the optical DLR, DLG, and DLB are incident on the light receiving elements 83R, 83G, and 83B, respectively, so that the incident spots are on the light receiving elements 83R, 83G, and 83B, respectively. A voltage corresponding to the total amount of light is generated. In this way, the detection voltage value data corresponding to the amount of light of the entire incident spot is input to the control unit 71 as a signal from each of the light receiving elements 83R, 83G, and 83B.

When the detected voltage value data is input to the control unit 71, the control unit 71 reads the above-mentioned reference value data from the storage unit 76, the detected voltage value data input from the light receiving element 83R, and the detected voltage value input from the light receiving element 83G. Each of the data and the detected voltage value data input from the light receiving element 83B is compared with the reference value data. In the present embodiment, this comparison is performed based on whether or not the absolute value of the difference between the detected voltage value data and the reference value data is within a predetermined range. When the absolute value of the difference between the detected voltage value data and the reference value data is within a predetermined range, the control unit 71 determines that the phase modulation element is not defective, and the absolute value is within the predetermined range. If not, it is determined that the phase modulation element is defective. As described above, the reference value data is data obtained in advance as a voltage value generated in each light receiving element 83R, 83G, 83B in a state where the phase modulation elements 54R, 54G, 54B are not defective. Therefore, the detected voltage value data according to the total amount of light of the incident spot can be substantially equal to the reference value data. Therefore, in this case, the control unit 71 determines that the absolute value of the difference between the detected voltage value data and the reference value data is within a predetermined range. In this way, the control unit 71 determines that the light distribution patterns of the optical DLR, DLG, and DLB have not changed, and that the phase modulation elements 54R, 54G, and 54B are not defective. As a result, the control unit 71 advances the detection process to step SP15.

On the other hand, if the phase modulation elements 54R, 54G, 54B are deteriorated or deviated from a predetermined standard at the time of manufacture, the phase modulation element is defective even when the same voltage as that of the non-defect phase modulation element is applied. The orientation of the liquid crystal molecules 66a of 54R, 54G, 54B may differ between the defective phase modulation element and the non-defective phase modulation element. As described above, when the same voltage is applied, the orientation of the liquid crystal molecules 66a is different, so that the light distribution patterns of the optical DLRs, DLGs, and DLBs are disrupted. The outer edge of the incident spot Sr may be blurred or the position of the incident spot Sr may be displaced, so that part or all of the incident spot Sr may protrude from the light receiving surface 83Rf. The shape of the incident spot Sr when it protrudes from the light receiving surface Rf is not always circular. In this case, the amount of light incident on the light receiving element is reduced and the voltage generated from the light receiving elements 83R, 83G, 83B becomes smaller than in the case where the entire incident spot Sr is not incident on the light receiving element. Therefore, for example, when only the phase modulation element 54R is defective, the detection voltage value data smaller than the reference value data is input from the light receiving element 83R to the control unit 71. Alternatively, when all of the phase modulation elements 54R, 54G, 54B are defective, detection voltage value data smaller than the reference value data is input from the light receiving elements 83R, 83G, 83B to the control unit 71.

When at least one of the phase modulation elements 54R, 54G, 54B is defective and the detected voltage value data is input to the control unit 71, the control unit 71 reads the reference value data from the storage unit 76 and these detected voltage values. Compare the data with the reference value data. As described above, at least one of the detection voltage value data input from the light receiving elements 83R, 83G, 83B to the control unit 71 is smaller than the reference value data. Therefore, when at least one of the absolute values of the difference between the detected voltage value data and the reference value data is not within a predetermined range, the control unit 71 changes at least one light distribution pattern of the optical DLR, DLG, and DLB. Judge that you are doing. In this way, the control unit 71 determines that at least one of the phase modulation elements 54R, 54G, 54B is defective. In this case, the control unit 71 controls the warning unit drive circuit 78 to output a drive signal from the warning unit drive circuit 78 to the warning unit 79. As a result, the control unit 71 advances the detection process to step SP14.

In the above description, an example in which the control unit 71 advances the detection process to step SP14 when it is determined that at least one of the phase modulation elements 54R, 54G, 54B is defective has been described, but the phase modulation elements 54R, 54G, 54B have been described. If it is determined that at least two of the above are defective, the control unit 71 may advance the detection process to step SP14, or if it is determined that all of the phase modulation elements 54R, 54G, 54B are defective, the control unit 71 may proceed. May proceed with the detection process to step SP14.

(Step SP14)
When the drive signal is input from the warning unit drive circuit 78 to the warning unit 79, the warning unit 79 issues a warning based on the drive signal. As described above, when the warning unit 79 composed of the light emitting diode is provided on the combination panel, the warning unit 79 emits light at a predetermined portion of the combination panel, and the driver or the like can use the phase modulation elements 54R, 54G. The defect of 54B can be grasped.

When the control unit 71 generates a warning to the warning unit 79, the control unit 71 advances the detection process to step SP15.

(Step SP15)
If the warning unit 79 issues a warning in step SP14, or if the control unit 71 determines in step SP13 that all of the phase modulation elements 54R, 54G, 54B are not defective, the control unit 71 causes the element drive circuits 60R, 60G. , 60B is controlled to apply a voltage different from that of step SP12 to the phase modulation elements 54R, 54G, 54B from the element drive circuits 60R, 60G, 60B. In this way, the control unit 71 switches from the detection mode to the standard mode. As a result, each optical path of the optical DLR, DLG, and DLB is deflected from the detected optical path OPE to the standard optical path OPS. The control unit 71 terminates the detection process after switching from the detection mode to the standard mode.

As described above, the control unit 71 in the present embodiment executes the detection process for a predetermined period from the start of light emission from the light sources 52R, 52G, 52B by performing steps SP11 to SP15.

By the way, in a vehicle lamp as described in Patent Document 1, when the phase modulation element is deteriorated or deviates from a predetermined standard, the light distribution pattern of the light emitted from the phase modulation element is changed. There is a concern that the designed light distribution pattern will collapse.

Therefore, in the vehicle headlight 1 of the present embodiment, the control unit 71 detects a change in the light distribution pattern of the phase modulation elements 54R, 54G, 54B based on the voltage generated from the light receiving elements 83R, 83G, 83B. Therefore, according to the vehicle headlight 1 of the present embodiment, it is possible to effectively detect a defect of the phase modulation elements 54R, 54G, 54B.

Further, in the vehicle headlight 1 of the present embodiment, since the optical paths of the optical DLR, DLG, and DLB are deflected to the detection optical path OPE in the detection mode, the light receiving elements 83R, 83G, and 83B are placed on the detection optical path OPE. Can be placed. By doing so, it is not necessary to arrange the light receiving elements 83R, 83G, 83B on the standard optical path OPS in order to detect the amount of light, and it is possible to prevent the light receiving element from being irradiated with light in the standard mode. To. Therefore, according to the vehicle headlight 1 of the present embodiment, it is possible to effectively detect defects in the phase modulation elements 54R, 54G, 54B while maintaining a good light distribution pattern of the light emitted to the outside.

Further, in the vehicle headlight 1 of the present embodiment, the phase modulation elements 54R, 54G, 54B are LCOS (Liquid Crystal On Silicon). Therefore, according to the vehicle headlight 1 in the present embodiment, the optical path of the optical DLR, DLG, DLB can be deflected by adjusting the voltage applied to the phase modulation elements 54R, 54G, 54B. Therefore, in order to deflect the optical path of the optical DLR, DLG, and DLB, it is not necessary to separately provide an optical component or the like, and the number of components can be reduced. Further, since LCOS is composed of liquid crystal molecules, the light distribution pattern tends to be greatly disrupted when it is defective. Therefore, by detecting the change in the light distribution pattern as described above, the defect of the phase modulation element can be detected more effectively.

Further, in the vehicle headlight 1 of the present embodiment, the control unit 71 temporarily determines whether or not the phase modulation elements 54R, 54G, 54B are defective while the light sources 52R, 52G, 52B are on. do. Therefore, according to the vehicle headlight 1 in the present embodiment, the load applied to the control unit 71 is reduced as compared with the case where it is always determined whether or not the phase modulation elements 54R, 54G, 54B are defective. obtain.

Further, in the vehicle headlight 1 of the present embodiment, the control unit 71 determines whether the light distribution pattern is a predetermined light distribution pattern at the timing when the light emission from the light sources 52R, 52G, 52B is started. .. Therefore, the driver or the like can quickly grasp the defect of the phase modulation element. Therefore, according to the vehicle headlight 1 in the present embodiment, the safety can be effectively enhanced.

Further, in the vehicle headlight 1 of the present embodiment, the light receiving elements 83R, 83G, and 83B are used as light amount sensors such as photodiodes, so that the light distribution pattern can be determined based on the light amount data. Therefore, according to the vehicle headlight 1 in the present embodiment, unlike the case where the light receiving element is an image pickup device described later, it is not necessary to determine the light distribution pattern based on the image comparison, and the algorithm of the detection process is simplified. Can be. Further, according to the vehicle headlight 1 in the present embodiment, by using the light receiving elements 83R, 83G, 83B as a light amount sensor such as a photodiode, a device such as a camera is used to acquire light distribution pattern data. It is not necessary to install it in the vehicle headlight 1, and the structure can be simplified.

Further, in the vehicle headlight 1 of the present embodiment, the period during which the detection process is executed is set to 1/30 second or less. The time resolution of human vision is approximately 1/30 second. Therefore, according to the vehicle headlight 1 in the present embodiment, the afterimage effect may occur when the period of the detection process is set to 1/30 second or less, and the driver or the like indicates that the detection process is biased to the OPE. Since it is difficult to recognize, safety can be maintained more effectively. In addition, in order to generate the afterimage effect more effectively, it is more preferable that the period of the detection process is 1/60 second or less.

(8th Embodiment)
Next, an eighth embodiment as a third aspect of the present invention will be described. Unless otherwise specified, the same or equivalent components as those in the seventh embodiment described above are designated by the same reference numerals, and duplicate description will be omitted.

In the vehicle headlight 1 of the present embodiment, the detection process is executed for a predetermined period after the emission of light from the light source is started at the point where the detection process is executed for a predetermined period from the time when the vehicle is stopped. It is mainly different from the vehicle headlight 1 in the seventh embodiment.

FIG. 24 is a block diagram including a vehicle headlight 1 according to an eighth embodiment of the present invention. As shown in FIG. 24, in the vehicle headlight 1 of the present embodiment, the vehicle speed sensor 75 is connected to the control unit 71.

FIG. 25 is a diagram showing an example of a flowchart showing control of the detection process by the control unit 71 in the present embodiment. In this embodiment, this detection process is performed, for example, for a period of 1/30 second or less. As shown in FIG. 25, this detection process comprises steps SP21-SP27.

(Step SP21)
In the present embodiment, the control unit 71 operates when the IG power supply (ignition power supply) of the vehicle is turned on. Therefore, the time when the IG power supply is turned on is the start of FIG. 25. First, when the above-mentioned light switch is turned on, a signal that the light switch is turned on is input to the control unit 71 via the ECU. In this case, the control unit 71 determines that the light switch is on, and advances the detection process to step SP22. On the other hand, when the signal that the light switch is turned on is not input to the control unit 71, the control unit 71 repeats the step SP21.

(Step SP22)
Similarly to the seventh embodiment, the control unit 71 controls the power supply circuit 59 based on the signal with the light switch turned on, and causes the power supply circuit 59 to supply electric power to the light sources 52R, 52G, 52B.

(Step SP23)
After power is supplied to the light sources 52R, 52G, 52B, when a signal having a speed of zero is input from the vehicle speed sensor 75 to the control unit 71, the control unit 71 determines that the vehicle has stopped, and steps SP24 in the detection process. Proceed to. On the other hand, when the signal whose speed is zero is not input, the control unit 71 determines that the vehicle is moving and returns the detection process to step SP21.

(Step SP24)
When the control unit 71 determines that the speed is zero, the control unit 71 controls the element drive circuits 60R, 60G, 60B and applies a voltage different from the standard mode to the phase modulation elements 54R, 54B, 54G as in the seventh embodiment. Let me. As a result, the vehicle headlight 1 is set to the detection mode.

Next, the control unit 71 determines whether or not the phase modulation elements 54R, 54B, 54G are defective by executing steps SP25 to SP27, and the phase modulation elements 54R, 54B, 54G are defective. If it is determined that, a warning is issued. Since these steps SP25 to SP27 are the same as those of steps SP13 to SP15 of the seventh embodiment, the description thereof will be omitted.

As described above, the control unit 71 in the present embodiment executes the detection process for a predetermined period after the vehicle has stopped by performing steps SP21 to SP27.

As described above, according to the present embodiment, the detection process is executed for a predetermined period from the time when the vehicle is stopped. By doing so, it is possible to effectively detect the defect of the phase modulation elements 54R, 54B, 54G as in the seventh embodiment.

Further, according to the vehicle headlight 1 of the present embodiment, since the control unit 71 executes the detection process while the vehicle is stopped, the safety can be improved as compared with the case where the detection process is performed while the vehicle is running. ..

Further, in the vehicle headlight 1 of the present embodiment, the period during which the detection process is performed is set to 1/30 second or less. Therefore, according to the vehicle headlight 1 in the present embodiment, the afterimage effect can occur as described above, and it becomes difficult for the driver or the like to recognize that the standard optical path OPS is deflected to the detected optical path OPE.

(9th Embodiment)
Next, a ninth embodiment as a third aspect of the present invention will be described. Unless otherwise specified, the same or equivalent components as those in the 7th and 8th embodiments described above are designated by the same reference numerals, and duplicate description will be omitted.

In the vehicle headlights 1 of the seventh and eighth embodiments, an example in which the light receiving elements 83R, 83G, and 83B are light amount sensors such as photodiodes has been described, but the light receiving element of the present embodiment is an image pickup element. .. In this respect, the vehicle headlight 1 of the present embodiment is mainly different from the vehicle headlight 1 of the seventh and eighth embodiments. Hereinafter, the vehicle headlight 1 of the present embodiment will be described.

FIG. 26 is a diagram showing an optical system unit 50 of a vehicle lamp according to the present embodiment from the same viewpoint as in FIG. As shown in FIG. 26, the optical system unit 50 of the present embodiment includes a first light receiving element 83R, a second light receiving element 83G, a third light receiving element 83B, a condensing lens 185R, 185G, 185B, and condensing light. The projection surface 184R on which the image of the first optical DLR transmitted through the lens 185R is projected, the projection surface 184G on which the image of the second optical DLG transmitted through the condenser lens 185G is projected, and the second light transmitted through the condenser lens 185B. It has a projection surface 184B on which an image of the optical DLB of 3 is projected. In the present embodiment, the light receiving elements 83R, 83G, and 83B are image pickup elements such as CMOS and CCD mounted on an image pickup device such as a camera. The light receiving elements 83R, 83G, 83B, the condenser lenses 185R, 185G, 185B, and the projection surfaces 184R, 184G, 184B are fixed to the cover 40 by a configuration (not shown). The condenser lenses 185R, 185G, and 185B are not essential components.

The condenser lens 185R and the projection surface 184R are arranged on the detection optical path OPE of the first optical DLR. Further, the condenser lens 185G and the projection surface 184G are arranged on the detection optical path OPE of the second optical DLG. Further, the condenser lens 185B and the projection surface 184B are arranged on the detection optical path OPE of the third optical DLB.

The first light receiving element 83R is arranged at a position where an image projected on the projection surface 184R can be imaged. The second light receiving element 83G is arranged at a position where an image projected on the projection surface 184G can be imaged. The third light receiving element 83B is arranged at a position where the image projected on the projection surface 184B can be imaged.

Next, the detection process by the control unit 71 of the vehicle headlight 1 of the present embodiment will be described. FIG. 27 is a diagram showing an example of a control flowchart of the detection process by the control unit 71 in the present embodiment. As shown in FIG. 27, this detection process includes steps SP31 to SP35 and is executed, for example, in a period of 1/30 second or less, as in the seventh embodiment.

Since step SP31 is the same as step SP11 of the seventh embodiment, the description thereof will be omitted.

(Step SP32)
When the signal with the light switch turned on is input to the control unit 71, the control unit 71 controls the power supply circuit 59 to supply power from the power supply circuit 59 to the light sources 52R, 52G, 52B. When a signal with the light switch turned on is input to the control unit 71, the control unit 71 controls the element drive circuits 60R, 60G, 60B, and the phase modulation element 54R, from the element drive circuits 60R, 60G, 60B, A predetermined voltage is applied to 54B and 54G. As a result, the vehicle headlight 1 is set to the detection mode, and the optical paths of the optical DLR, DLG, and DLB are set to the detection optical path OPE. In the present embodiment, the light distribution pattern of the optical DLR, DLG, and DLB in the detection mode is a light distribution pattern in which the low beam light distribution pattern PL is formed. Therefore, in this step, the optical DLR, DLG, and DLB are condensed by the condenser lenses 185R, 185G, and 185B, respectively, and the images of the optical DLR, DLG, and DLB having substantially the same shape as the low beam light distribution pattern PL are obtained. It is projected on the projection planes 184R, 184G, and 184B, respectively.

FIG. 28 is a front view schematically showing the projection surface 184R. As shown in FIG. 28, when the optical path of the optical DLR is the detection optical path OPE, an image of the optical DLR having a shape substantially equal to that of the low beam light distribution pattern PL is projected on the projection surface 184R as described above. In FIG. 28, the image IM shown by the solid line shows the image of the optical DLR when the phase modulation element 54R is not defective, and the image IMa shown by the broken line shows the case where the phase modulation element 54R is defective. It shows an image of optical DLR.

(Step SP33)
When the phase modulation elements 54R, 54G, 54B are not defective, the image IM shown by the solid line in FIG. 28 is projected on the projection surface 184R, 184G, 184B as described above. In this step, the light receiving elements 83R, 83G, and 83B, which are image pickup elements, take an image IM of the optical DLR, DLG, and DLB, respectively, and output the electric signal of these image IMs to the control unit 71. The control unit 71 processes this electric signal to generate detection image data of each image IM of the optical DLR, DLG, and DLB.

In the present embodiment, in the storage unit 76, image data of the optical DLR, DLG, DLB projected on the projection surfaces 184R, 184G, 184B when the phase modulation elements 54R, 54G, 54B are not defective is stored in advance as reference image data. It is stored. When the control unit 71 generates the detected image data, the control unit 71 reads the reference image data from the storage unit 76 and compares the detected image data with the reference image data. This image comparison can be performed using known methods. In the present embodiment, after the detected image data and the reference image data are associated with the two-dimensional coordinates, how much the arbitrary feature points of the detected image data are separated from the feature points of the reference image data corresponding to the feature points. The match between the two images is judged based on whether or not the images match. When the distance between the feature points corresponding to each other is within a predetermined range, the control unit 71 estimates that both images match. In this case, the control unit 71 determines that the light distribution patterns of the optical DLR, DLG, and DLB have not changed, and as a result, determines that the phase modulation elements 54R, 54G, and 54B are not defective. On the other hand, when the separation distance exceeds a predetermined range, the control unit 71 estimates that the two images do not match. In this case, the control unit 71 determines that at least one of the optical DLR, DLG, and DLB light distribution patterns has changed, and as a result, determines that at least one of the phase modulation elements 54R, 54G, and 54B is defective. do.

If the detection image data described above is data generated when the phase modulation elements 54R, 54G, 54B are not defective, the separation distance is within a predetermined range. Therefore, the control unit 71 estimates that the detected image data and the reference image data match. In this case, the control unit 71 determines that the light distribution patterns of the optical DLR, DLG, and DLB have not changed, and determines that the phase modulation elements 54R, 54G, and 54B are not defective. As a result, the control unit 71 advances the detection process to step SP35.

On the other hand, if the phase modulation elements 54R, 54G, 54B are defective, as described above, the light distribution pattern of the optical DLR, DLG, DLB is disrupted due to the change in the orientation of the liquid crystal molecules 66a, and the projection surface 184R, The image projected on the 184G and 184B may be blurred. In this case, an image that is wider than the image IM can be projected on the projection surfaces 184R, 184G, and 184B, for example, as in the image IMa of FIG. 28. Therefore, when the phase modulation elements 54R, 54G, 54B are defective, the light receiving elements 83R, 83G, 83B take an image of the optical DLR, DLG, DLB image IMa, and send the electric signal of these image IMa to the control unit 71. Output. The control unit 71 processes this electric signal to generate detection image data of each image IMa of the optical DLR, DLG, and DLB. The control unit 71 reads the reference image data from the storage unit 76 and compares the detected image data with the reference image data. When the separation distance is not within the predetermined range, the control unit 71 estimates that the detected image data and the reference image data do not match. In this case, the control unit 71 determines that at least one of the optical DLR, DLG, and DLB light distribution patterns has changed, and thereby determines that at least one of the phase modulation elements 54R, 54G, and 54B is defective. do. As a result, the control unit 71 outputs a drive signal to the warning unit 79 and advances the detection process to step SP34.

Next, the control unit 71 executes step SP35 and step SP34. Since these step SP35 and step SP34 are the same as those of step SP15 and step SP14 of the seventh embodiment, the description thereof will be omitted.

As described above, the control unit 71 in the present embodiment executes the detection process for a predetermined period from the start of light emission from the light sources 52R, 52G, 52B by performing steps SP31 to SP35.

As described above, according to the vehicle headlight 1 of the present embodiment, since the light receiving elements 83R, 83G, and 83B can be configured by the image pickup element and the detection process can be executed, the light distribution pattern can be determined based on the image recognition. Changes can be detected, and the accuracy and accuracy of determining changes in the light distribution pattern can be improved.

In this embodiment, an example in which the light receiving element of the seventh embodiment is changed from the light amount sensor to the image pickup element has been described, but the light receiving element of the eighth embodiment may be changed from the light amount sensor to the image pickup element.

Further, in the present embodiment, an example in which the image projected on the projection surfaces 184R, 184G, 184B is substantially equal to the low beam light distribution pattern PL has been described, but the voltage applied to the phase modulation elements 54R, 54G, 54B in the detection mode has been described. Is set to a voltage such that the light distribution pattern of the light DLR, DLG, DLB emitted from the phase modulation elements 54R, 54G, 54B is different from the light distribution pattern PL of the low beam, and the light distribution pattern PL of the low beam is set. An image for a detection mode different from that of the image may be projected. As an image for such a detection mode, for example, a checkered image IP as shown in FIG. 29 can be mentioned. This image IP is an image projected on the projection surface 184R, 184G, 184B when the phase modulation elements 54R, 54G, 54B are not defective. In this case, if the phase modulation elements 54R, 54G, 54B become defective, the outer edge of the checkered pattern becomes blurred, and an image such as the image IPa as shown in FIG. 30 is projected on the projection surface 184R, 184G, 184B. obtain. When comparing the image IP and the image IPa, since the outer edge of the image IP is defined in a straight line, the distortion of the image IPa with respect to the outer edge of the image IP can be easily calculated in the step SP33. Therefore, the accuracy and accuracy of the image comparison can be further improved as compared with the case where the image of the low beam light distribution pattern PL is projected. When a voltage is applied so that the light distribution pattern becomes an image IP in this way, if the period of the detection process is set to 1/30 second or less, the above-mentioned afterimage effect occurs and the light distribution pattern is changed. It may be difficult for the driver or the like to recognize that.

(10th Embodiment)
Next, a tenth embodiment as a third aspect of the present invention will be described. Unless otherwise specified, the same or equivalent components as those in the 7th to 9th embodiments described above are designated by the same reference numerals, and duplicate description will be omitted.

In the vehicle headlights 1 of the seventh to ninth embodiments, an example in which a change in the light distribution pattern of the light DLR, DLG, DLB received by the light receiving elements 83R, 83G, 83B is temporarily determined has been described. However, in the vehicle headlight 1 of the present embodiment, the change in the light distribution pattern of the light DLR, DLG, DLB received by the light receiving elements 83R, 83G, 83B is constantly determined while the light source is operating. .. Mainly in this respect, the vehicle headlight 1 of the present embodiment is different from the vehicle headlight 1 of the seventh to ninth embodiments. Hereinafter, the vehicle headlight 1 of the present embodiment will be described.

FIG. 31 is a diagram showing an optical system unit 50 of a vehicle lamp according to the present embodiment from the same viewpoint as in FIG. As shown in FIG. 31, the vehicle headlight 1 of the present embodiment has a first spectroscopic unit 581R arranged between the first phase modulation element 54R and the first optical element 55f in the front-rear direction and a vertical direction. The second spectroscopic unit 581G arranged between the second phase modulation element 54G and the first optical element 55f, and the third phase modulation element 54B and the second optical element 55s arranged in the vertical direction in the vertical direction. It has 3 spectroscopic units 581B and. In the present embodiment, these spectroscopic units 581R, 581G, and 581B are, for example, half mirrors configured to transmit 99% of light and reflect 1% of light.

The first spectroscopic unit 581R is fixed to the cover 40 in a state of being tilted by approximately 45 ° in the front-rear direction and the up-down direction. The second spectroscopic unit 581G is fixed to the cover 40 in a state of being inclined by approximately 45 ° in the direction opposite to the first spectroscopic unit 581R in the front-rear direction and the vertical direction. The third spectroscopic unit 581B is fixed to the cover 40 in a state of being inclined by approximately 45 ° in the same direction as the first spectroscopic unit 581R in the front-rear direction and the vertical direction.

A first light receiving element 83R composed of a photodiode is arranged above the first spectroscopic unit 581R, and a second light receiving element 83G composed of a photodiode is arranged behind the second spectroscopic unit 581G. A third light receiving element 83B composed of a photodiode is arranged in front of the third spectroscopic unit 581B.

Further, in the present embodiment, the phase modulation elements 54R, 54G, 54B have a three-dimensional structure such that the optical DLRs, DLGs, and DLBs emitted from the phase modulation elements 54R, 54G, 54B have a low beam light distribution pattern PL. It is a diffraction grating.

In such a configuration, when light is emitted from the light source 52R, the light is collimated by the collimating lens 53R and then incident on the phase modulation element 54R. The light incident on the phase modulation element 54R becomes a low beam light distribution pattern PL by passing through the three-dimensional structure of the phase modulation element 54R, and is emitted forward as the first optical DLR. Further, when light is emitted from the light sources 52G and 52B, these lights are collimated by the collimating lenses 53G and 53B and then incident on the phase modulation elements 54G and 54B. The light incident on the phase modulation elements 54G and 54B passes through the three-dimensional structure of the phase modulation elements 54G and 54B to form a low beam light distribution pattern PL. In this way, the optical DLG and DLB are emitted upward, respectively.

The first optical DLR is incident on the first spectroscopic unit 581R arranged in front. As a result, most of the optical DLR passes through the first spectroscopic unit 581R and is emitted forward, and the remaining part of the optical DLR is reflected by the first spectroscopic unit 581R and propagates upward. In this way, a part of the first optical path DLR is separated from the standard optical path OPS to the detection optical path OPE. The second optical DLG is incident on the second spectroscopic unit 581G arranged above. As a result, most of the optical DLG passes through the second spectroscopic unit 581G and is emitted upward, and the remaining part of the optical DLG is reflected by the second spectroscopic unit 581G and propagates backward. In this way, a part of the second optical DLG is separated from the standard optical path OPS to the detection optical path OPE. The third optical DLB is incident on the third spectroscopic unit 581B arranged above. As a result, most of the optical DLB passes through the third spectroscopic unit 581B and is emitted upward, and the remaining part of the optical DLB is reflected by the third spectroscopic unit 581B and propagates forward. In this way, a part of the optical DLB is separated from the standard optical path OPS into the detected optical path OPE.

Most of the light DLRs, DLGs, and DLBs transmitted through the spectroscopic units 581R, 581G, and 581B are combined by the synthetic optical system 55 to become the second synthetic light LS2, and a low beam is formed.

On the other hand, the above-mentioned part of the optical DLR propagates through the detection optical path OPE and continues to be incident on the light receiving element 83R arranged above while the light source 52R is operating. Further, the above-mentioned part of the optical DLG propagates through the detection optical path OPE and continues to be incident on the light receiving element 83G arranged behind the light source 52G while the light source 52G is operating. Further, the above-mentioned part of the optical DLB propagates through the detection optical path OPE and continues to be incident on the light receiving element 83B arranged in front while the light source 52B is operating.

Hereinafter, the detection process of such a vehicle headlight 1 will be described. FIG. 32 is a diagram showing an example of a control flowchart of the control unit 71 in the present embodiment. As shown in FIG. 32, the detection process in this embodiment includes steps S41 to S44.

(Step SP41)
This step is the same as step SP11 of the seventh embodiment. Therefore, detailed description thereof will be omitted.

(Step SP42)
When the signal that the light switch is turned on is input to the control unit 71, the control unit 71 turns on the light sources 52R, 52G, 52B. As a result, as described above, most of the light emitted from the light sources 52R, 52G, 52B is emitted to the outside through the opening 40H. On the other hand, a part of the light is separated by the spectroscopic units 581R, 581G, 581B and continues to be incident on the light receiving elements 83R, 83G, 83B while the light sources 52R, 52G, 52B are operating. As a result, while the light sources 52R, 52G, 52B are operating, the detection voltage value data from the light receiving elements 83R, 83G, 83B continues to be input to the control unit 71.

(Step SP43)
The phase modulation elements 54R, 54G, 54B composed of the diffraction grating have a shape different from that at the time of design due to high temperature or deviation from the standard at the time of manufacture. The light incident on the 54B has a different diffraction than at the time of design. As a result, when the optical DLR, DLG, and DLB are emitted from the phase modulation elements 54R, 54G, 54B, these lights can have a light distribution pattern different from that at the time of design. In this case, as described above, the amount of light incident on the light receiving elements 83R, 83G, 83B may change, and the voltage generated from the light receiving elements 83R, 83G, 83B may change. Therefore, also in this step, as in step SP13 of the seventh embodiment, the control unit 71 determines whether or not the absolute value of the difference between the detected voltage value data and the reference value data is within a predetermined range. to decide. When the absolute value is within a predetermined range, the control unit 71 determines that the light distribution pattern has not changed and that the phase modulation elements 54R, 54G, 54B are not defective. As a result, the control unit 71 returns the detection process to step SP41.

On the other hand, when the absolute value is not within the predetermined range, the control unit 71 determines that the light distribution pattern has changed, and determines that the phase modulation elements 54R, 54G, 54B are defective. As a result, the control unit 71 outputs a drive signal to the warning unit 79 and advances the detection process to step SP44.

(Step SP44)
When the drive signal is input from the control unit 71 to the warning unit 79, the warning unit 79 issues a warning based on the drive signal. When the control unit 71 issues a warning to the warning unit 79, the control unit 71 returns the detection process to step SP41.

As described above, the control unit 71 in the present embodiment repeats the above detection process while the light sources 52R, 52G, and 52B are on, and constantly determines whether the orientation pattern is a predetermined light distribution pattern.

As described above, in the vehicle headlight 1 of the present embodiment, the control unit 71 has a light distribution pattern of light received by the light receiving elements 83R, 83G, 83B while the light sources 52R, 52G, 52B are on. Is always determined whether is a predetermined light distribution pattern. Therefore, the driver or the like can grasp on-time that the phase modulation elements 54R, 54G, 54B have become defective.

Further, in the vehicle headlight 1 of the present embodiment, since the phase modulation elements 54R, 54G, 54B are used as diffraction gratings, the step of adjusting the voltage applied to the phase modulation elements 54R, 54G, 54B is unnecessary. be. Therefore, it may be easier to build an algorithm for the detection process.

Further, in the vehicle headlight 1 of the present embodiment, the polarization from the standard optical path OPS to the detected optical path OPE is performed by the spectroscopic unit. Therefore, according to the vehicle headlight 1 in the present embodiment, the optical path is deflected by changing the orientation pattern of the liquid crystal molecules 66a of the phase modulation elements 54R, 54G, 54B as in the seventh to ninth embodiments. The optical path can be deflected more than the above. Therefore, according to the vehicle headlight 1 in the present embodiment, the light receiving surface and the light receiving element are placed at a position farther from the standard optical path OPS as compared with the case where the optical path is deflected by the phase modulation elements 54R, 54G, 54B. Can be placed. Therefore, according to the vehicle headlight 1 in the present embodiment, it is possible to more effectively suppress the irradiation of the light propagating in the standard optical path OPS to the light receiving surface and the light receiving element, and the collapse of the light distribution pattern is further prevented. Can be effectively suppressed.

In this embodiment, an example in which the phase modulation elements 54R, 54G, 54B are diffraction gratings has been described, but as in the seventh to ninth embodiments, the light emitted from the phase modulation elements 54R, 54G, 54B is emitted. It may be a phase modulation element such as LCOS that can change the light distribution pattern of the above from a predetermined light distribution pattern. When the phase modulation element is LCOS in the present embodiment, for example, a part of the light emitted from the phase modulation element propagates in the detection optical path OPE, and the other components of the light propagate in the standard optical path OPSE. By changing the refractive index of the liquid crystal layer of the phase modulation element as described above, it is possible to constantly determine whether the orientation pattern is a predetermined light distribution pattern.

(11th Embodiment)
Next, the eleventh embodiment as the third aspect of the present invention will be described. In the seventh to tenth embodiments, an example in which the light receiving element receives light propagating in the detection optical path OPE has been described, but the light receiving element of the present embodiment receives light propagating in the standard optical path OPS. In this respect, the vehicle headlight 1 of the present embodiment is different from the vehicle headlight 1 of the seventh to tenth embodiments. Hereinafter, such a vehicle headlight 1 will be described.

FIG. 33 is a diagram showing the vehicle lamp according to the present embodiment from the same viewpoint as in FIG. As shown in FIG. 33, the vehicle headlight 1 of the present embodiment has a camera 683 arranged in the light chamber R. The camera 683 is arranged outside the cover 40 and is fixed to the housing 10 by a configuration (not shown). The camera 683 has a CMOS or a CCD as a light receiving element, and the light receiving element is arranged so as to receive light propagating in the standard optical path OPS. For example, when a projection surface is arranged in front of the vehicle headlight 1 during an inspection such as a vehicle inspection, this light receiving element emits an image to the outside by a standard optical path OPS and is projected on the projection surface. Take an image. The control unit 71 of the present embodiment determines, for example, the difference between the images projected on the projection surface in the same manner as in step SP33 of the ninth embodiment. By doing so, it is possible to detect whether or not the phase modulation elements 54R, 54G, 54B are defective, or whether or not the phase modulation elements 54R, 54G, 54B are defective due to a yield product or the like.

As described above, according to the vehicle headlight 1 of the present embodiment, the light receiving element is configured to receive the light propagating in the standard optical path OPS, so that the phase modulation elements 54R, 54G, and 54B are defective. It may not be necessary to deflect the optical path to the detection optical path OPE in order to detect.

In this embodiment, the control unit 71 may constantly determine whether the light distribution pattern of the light received by the light receiving element is a predetermined light distribution pattern while the light sources 52R, 52G, and 52B are on. , May be judged temporarily.

Although the third aspect of the present invention has been described above by exemplifying the seventh to eleventh embodiments, the third aspect of the present invention is not limited thereto.

For example, in the seventh embodiment, the timing at which the detection process is activated is set to the time when the light source is started, and in the eighth embodiment, the timing is set to the time when the vehicle is stopped. However, when the control unit 71 temporarily determines the light distribution pattern detected by the light receiving elements 83R, 83G, 83B while the light sources 52R, 52G, 52B are on, the timing of this determination is not particularly limited. For example, a change in the light distribution pattern may be detected while the vehicle is traveling. In this case, if the period of the detection process is set to 1/30 second or less, the afterimage effect may occur as described above, and the driver or the like may not recognize the discomfort that the optical path is deflected during traveling.

Further, in the seventh to ninth embodiments, as an example, the control unit 71 temporarily determines whether the light distribution pattern of the light received by the light receiving element is a predetermined light distribution pattern while the light source is on. The case where the phase modulation elements 54R, 54G, 54B are LCOS has been described. However, in the seventh to ninth embodiments, the phase modulation elements 54R, 54G, 54B may be used as a diffraction grating. In this case, a spectroscopic unit is provided on the standard optical path OPS to disperse a part of the light on the detection optical path OPE, and then the separated light at a predetermined time point while the light sources 52R, 52G, 52B are operating. The control unit 71 may determine the change in the light distribution pattern based on the data. By doing so, even when the phase modulation elements 54R, 54G, 54B are diffraction gratings, the change in the light distribution pattern can be temporarily determined.

Further, in the seventh to ninth embodiments, the example in which LCOS is used as the phase modulation element whose refractive index can be changed has been described, but other phase modulation elements whose refractive index can be changed may be used. For example, GLV may be mentioned as such another phase modulation element.

Further, in the seventh, eighth, and tenth embodiments, an example in which a photodiode is used as the light amount sensor has been described, but for example, a thermistor or the like may be used as another light amount sensor.

Further, in the 7th to 10th embodiments, both the image pickup device and the light intensity sensor may be provided. For example, the image sensor may receive the light emitted from the light sources 52R and 52G, and the light amount sensor may receive the light emitted from the light source 52B.

Further, in the seventh to eleventh embodiments, an example of determining a defect for all of the phase modulation elements 54R, 54G, 54B has been described, but one or two of the phase modulation elements 54R, 54G, 54B have a defect. You may try to judge. In this case, since the number of defects to be determined is reduced, the detection process can be simplified.

Further, in the seventh to eleventh embodiments, the example in which the vehicle headlight 1 has a plurality of light sources has been described, but only one or more light sources may be used. However, by providing a plurality of light sources that emit light having different wavelengths, it is possible to generate light of a desired color.

Further, in the seventh to eleventh embodiments, the vehicle headlight 1 as the vehicle lighting device is supposed to irradiate a low beam, but the vehicle lighting device as the third aspect of the present invention is not particularly limited. For example, the vehicle lighting fixture in another embodiment as the third aspect irradiates the region shown by the broken line in FIG. 22, that is, the region above the region to which the low beam is irradiated, with light having a lower intensity than the low beam. It may be configured to do so. Such low-intensity light is referred to as, for example, light OHS for marker recognition. In this case, it is preferable that the light emitted from the respective phase modulation elements 54R, 54G, 54B contains the optical OHS for tag recognition. Further, in such an embodiment, it can be understood that a light distribution pattern for night illumination is formed by the low beam and the light OHS for sign recognition. The term "night" here is not limited to the meaning of "night", but includes a dark place such as a tunnel. Further, the vehicle lamp according to another embodiment as a third aspect may be configured to irradiate a high beam as shown in FIG. 34. In FIG. 34, the light distribution pattern PH of the high beam is shown by a thick line, and the straight line S represents a horizontal line. In the high beam light distribution pattern PH, the region PHA1 is a region having a strong light intensity, and PHA2 is a region having a lower light intensity than the PHA1. Further, in still another embodiment as the third aspect, the vehicle lamp according to the third aspect of the present invention may be applied as emitting light constituting an image. In such a case, the direction of the light emitted from the vehicle lamp and the mounting position of the vehicle lamp in the vehicle are not particularly limited.

According to the first aspect of the present invention, a vehicle headlight capable of improving visibility in the traveling direction while being miniaturized is provided, and according to the second aspect of the present invention, it is possible to suppress feeling uncomfortable. A vehicle headlight to be obtained is provided, and according to a third aspect of the present invention, a vehicle headlight capable of detecting a defect of a phase modulation element is provided and can be used in a field such as an automobile.

Claims (27)

Light source and
A phase modulation element that diffracts light emitted from the light source with a changeable phase modulation pattern and emits light having a predetermined light distribution pattern based on the phase modulation pattern.
Control unit and
Equipped with
The control unit is a vehicle headlight that adjusts the phase modulation pattern and changes the light emission direction of the predetermined light distribution pattern while maintaining the predetermined light distribution pattern. The vehicle headlight according to claim 1, further comprising a projection lens through which light emitted from the phase modulation element is transmitted. The vehicle headlight according to claim 1 or 2, wherein the control unit adjusts the phase modulation pattern according to an inclination angle in the pitch direction of the vehicle, and changes the emission direction in the vertical direction. The vehicle headlight according to any one of claims 1 to 3, wherein the control unit adjusts the phase modulation pattern according to the speed of the vehicle and changes the emission direction in the vertical direction. .. The vehicle headlight according to any one of claims 1 to 4, wherein the control unit adjusts the phase modulation pattern according to the steering angle of the vehicle and changes the emission direction to the left-right direction. light. When the emission direction is changed, the control unit is within a region that does not overlap with the predetermined light distribution pattern in which the emission direction is changed in the predetermined light distribution pattern before the emission direction is changed. The phase modulation pattern is adjusted so that light different from the light of the light distribution pattern of is irradiated.
One of claims 1 to 5, wherein the brightness of the light emitted into the region is darker than the brightness of the region in the predetermined light distribution pattern before the emission direction is changed. Headlights for vehicles as described in. The vehicle headlight according to any one of claims 1 to 6, wherein the emission direction is gradually changed. Light source and
A phase modulation element that diffracts light emitted from the light source with a changeable phase modulation pattern and emits light having a predetermined light distribution pattern based on the phase modulation pattern.
Control unit and
Equipped with
The control unit adjusts the phase modulation pattern and continuously changes the outer shape of the predetermined light distribution pattern to obtain a light distribution pattern having a different outer shape from the predetermined light distribution pattern. Headlight. The eighth aspect of the present invention is characterized in that the control unit adjusts the phase modulation pattern according to the speed of the vehicle to make the predetermined light distribution pattern smaller than the predetermined light distribution pattern. Headlights for vehicles. The control unit adjusts the phase modulation pattern when the speed of the vehicle becomes a predetermined value or more, and makes the predetermined light distribution pattern smaller than the predetermined light distribution pattern. The vehicle headlight according to claim 8. The vehicle headlight according to claim 9 or 10, wherein the outer shape of the light distribution pattern smaller than the predetermined light distribution pattern is similar to the outer shape of the predetermined light distribution pattern. The eighth aspect of the present invention is characterized in that the control unit adjusts the phase modulation pattern according to a signal from a turn switch of a vehicle to make the predetermined light distribution pattern into a light distribution pattern widened in the left-right direction. The listed vehicle headlights. The vehicle according to claim 8, wherein the control unit adjusts the phase modulation pattern according to the steering angle of the vehicle to make the predetermined light distribution pattern into a light distribution pattern widened in the left-right direction. Headlight for use. A light source that emits light and
A phase modulation element that diffracts the light into a predetermined light distribution pattern,
A light receiving element that receives a part of the light diffracted by the phase modulation element, and a light receiving element.
Control unit and
Equipped with
The control unit is characterized in that it determines whether or not the light distribution pattern of the light is the predetermined light distribution pattern based on the signal from the light receiving element that has received a part of the light. .. The vehicle lighting device according to claim 14, wherein the light receiving element receives the light propagating in an optical path different from the optical path of the light emitted from the phase modulation element to the outside of the vehicle lighting device. The phase modulation element is characterized in that at least a part of the light emitted from the phase modulation element is deflected to an optical path different from the optical path of the light emitted from the phase modulation element to the outside of the vehicle lighting equipment. The vehicle lighting device according to claim 15. The present invention is characterized by further comprising a spectroscopic unit that disperses a part of the light emitted from the phase modulation element into an optical path different from the optical path of the light emitted from the phase modulation element to the outside of the vehicle lamp. The vehicle lighting fixture according to 15. The vehicle lighting device according to any one of claims 14 to 17, wherein the light receiving element is an image pickup element that captures an image of the light. Further, a projection surface arranged on an optical path different from the optical path of light emitted from the phase modulation element to the outside of the vehicle lamp is further provided.
The vehicle lamp according to claim 18, wherein the image pickup device captures an image of the light projected on the projection surface. The vehicle according to claim 18 or 19, wherein the phase modulation element changes the light distribution pattern of the light emitted from the phase modulation element to a light distribution pattern different from the predetermined light distribution pattern. Lighting equipment. One of claims 15 to 17, wherein the light receiving element is a light amount sensor arranged on an optical path different from the optical path of light emitted from the phase modulation element to the outside of the vehicle lamp. Vehicle lighting fixtures as described in the section. Any of claims 14 to 21, wherein the control unit constantly determines whether the light distribution pattern of the light received by the light receiving element is the predetermined light distribution pattern while the light source is on. Or the vehicle lighting equipment described in item 1. Claims 14 to 21 are characterized in that the control unit temporarily determines whether the light distribution pattern of the light received by the light receiving element is the predetermined light distribution pattern while the light source is on. The vehicle lighting equipment according to any one of the above items. The control unit is characterized in that it determines whether the light distribution pattern of the light received by the light receiving element is the predetermined light distribution pattern for a predetermined period after the emission of the light from the light source is started. The vehicle lighting equipment according to claim 23. The control unit is characterized in that it determines whether the light distribution pattern of the light received by the light receiving element is the predetermined light distribution pattern for a predetermined period while the vehicle equipped with the light source is stopped. The vehicle lighting equipment according to claim 23. The one according to any one of claims 23 to 25, wherein the control unit determines whether or not the light distribution pattern of the light is the predetermined light distribution pattern in a period of 1/30 second or less. Light fixtures for vehicles. The vehicle lighting device according to claim 16 or 20, wherein the phase modulation element is an LCOS (Liquid Crystal On Silicon).

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