JP2018195779A - Light projection device - Google Patents

Abstract

To provide a light projection device which is downsized and capable of projecting a light while distributing a lot of lights over a predetermined direction range in a uniform manner as further as possible even if a pseudo light source is generated in a light-emitting device (lens effect package).SOLUTION: A light projection device 1 comprises: a light-emitting device (lens effect package) 10 including an LED element 12; and an optical member 20 which projects a light from the light-emitting device 10 while aligning a direction of the light. The light-emitting device 10 includes an encapsulation resin 13 for encapsulating the LED element 12. The optical member 20 includes: an incidence plane 29 to which a light from the light-emitting device 10 is incident; and an emission plane 21 which emits the incident light. The optical member 20 includes, on the incidence plane 29, a light guide part 27 extending so as to enclose a portion where a light is emitted, of the light-emitting device 10 and guiding the light that is incident from the light-emitting device 10, towards the emission plane 21.SELECTED DRAWING: Figure 1

Description

  The present invention relates to an optical projection device.

In recent years, a device for projecting light (light projection device) is attached to a car or the like and used for various purposes. For example, a technology for recognizing an object around a vehicle by providing a light projection device and a sensor for projecting infrared light in the vehicle and detecting reflected light of the light projected from the light projection device with the sensor. It has been known. In addition, a light projection device that projects infrared light to a driver who is driving a vehicle at night so that the driver does not interfere with driving and images the driver with an infrared camera is also used. .
In an optical projection device used for such purposes, it is required to make the light distribution of light emitted from an LED (light emitting device) a narrow light distribution in order to improve sensing accuracy. That is, it is required to direct light emitted from the LED in a predetermined direction as much as possible and to project the light as uniformly as possible in a predetermined range.
As an apparatus for projecting light in a predetermined direction, for example, as in Patent Document 1, an LED is placed at the focal position of a parabolic reflecting surface, and light from the LED is reflected by this reflecting surface. A technique for making parallel light is known.

  Here, in the light-emitting device using LED, the LED element arrange | positioned on a board | substrate may be enclosed with transparent resin whose heat conductivity is higher than air. In particular, in a light emitting device with a large output, the LED element is generally encapsulated with a resin as a countermeasure against heat generation. However, the encapsulating resin that encapsulates the LED element on the substrate has a lens effect. Here, the LED element of the light emitting device enclosed in a resin is referred to as a lens effect package. In the light emitting device having such a lens effect package, the LED element is refracted or reflected by the LED light at the boundary surface between the encapsulating resin and the air based on the shape of the encapsulating resin having the lens effect and the size of the LED element. A pseudo light source is generated in such a state that light is emitted from other parts. In this case, if the light projection device is designed without considering the pseudo light source in consideration of only the light emission from the LED element, the light distribution characteristic of the light projection device is deteriorated due to the light from the pseudo light source. There is a problem that non-uniform illumination is caused by the light distribution.

Therefore, the inventors have conducted various studies on a reflector having a parabolic reflecting surface and an optical projection device having an enclosed LED, and encapsulating the reflector by using the positional relationship between the reflector and the LED or using a Fresnel lens together. The problem of the light distribution due to the generation of the pseudo light source of the led LED has been solved.
This light projection device includes, for example, a substantially conical cylindrical (trumpet-shaped, bell-shaped) reflector composed of a paraboloid, a lens effect package (light emitting device) disposed on the small diameter side of the reflector, and a large reflector. And a Fresnel lens arranged to close the opening on the radial side opening. As for the size of such a light projection device, for example, the outer diameter of the Fresnel lens having a diameter larger than that of the reflector is φ9.75 mm, and the total length of the light projection device (from the lens effect package to the Fresnel lens) is 11 mm. In this case, the size of the lens effect package (light emitting device) is such that the length of one side of the substrate (square) is 3.95 mm, and the height orthogonal to the substrate (height of the encapsulating resin portion) is 2.41 mm. It was.

JP 2008-4296 A

  By the way, in a device to be mounted on a vehicle, miniaturization is generally demanded, and an optical projection device is no exception, and there is a demand for miniaturization. The axial direction of the optical projection device (full length direction, optical axis direction) The diameter orthogonal to the length and the length along the axial direction are limited. In that case, for example, it is difficult in size to adopt a configuration in which a Fresnel lens is used in addition to a reflector having a parabolic reflecting surface in consideration of a pseudo light source.

  The present invention has been made in view of the above circumstances, and is a small-sized light that can project light by distributing as much light as possible in a predetermined direction range even if a pseudo light source is generated in a light emitting device (lens effect package). An object is to provide a projection device.

In order to achieve the above object, an optical projection apparatus of the present invention includes a lens effect package including an LED element encapsulated in an encapsulating member on an LED substrate, and an optical that projects the light from the lens effect package while adjusting the direction of light. With members,
The optical member includes an incident surface on which light from the lens effect package is incident, and an output surface from which incident light is emitted.
The optical member extends on the incident surface so as to surround a periphery of a portion where the light of the lens effect package is emitted, and guides light incident from the lens effect package toward the emission surface. A light guide is provided.

According to such a configuration, the light emitted from the lens effect package (light emitting device) is directed from the incident surface of the optical member to the outer peripheral surface of the optical member, and finally emitted outside the predetermined direction range set at the time of design. In the present invention, when the light emitted from the light-emitting device is directed to the outside of the incident surface without hitting the incident surface of the optical member, in the present invention, the light hits the light guide portion, and the light incident on the light guide portion is refracted. In addition, it is possible to increase the possibility that light is guided to the emission surface side by one or more reflections in the optical member, and the light is emitted within a predetermined direction range.
The exit surface is preferably a convex surface so that the diffused light from the LED element is parallel light or condensed, and may be spherical or aspherical.

In addition, in the light emitting device, a pseudo light source is generated by an encapsulating member (encapsulating resin), and the light from the pseudo light source is largely shifted from the direction in which the light is to be projected, resulting in a wide light distribution, or a non-uniform light distribution It can be suppressed by the light guide part.
For example, a portion where light is concentrated on the surface portion of the encapsulating member due to reflection or refraction at the boundary surface between the enclosing member and the outside air becomes a pseudo light source that behaves as if it is emitting light like a light source. Although the position and number of the pseudo light sources vary depending on the shape of the LED element and the enclosing member, for example, many pseudo light sources may be generated in an annular portion (a donut-like portion) excluding the central portion of the enclosing member. The problem with the pseudo light source is when the direction of light from the pseudo light source is significantly different from the direction of light from the light emitting surface of the LED element, for example, from the center side of the optical member toward the outer peripheral side. When such light reaches the light guide part outside the encapsulating resin from the pseudo light source of the encapsulating resin, the light incident on the light guide part is not the outer peripheral surface side due to, for example, refraction and one or more reflections in the light guide part. Guided to the side. Thereby, even if a pseudo light source is generated by the enclosing member, it is possible to narrow the light distribution and distribute a large amount of light in a predetermined direction range, and to make the light distribution uniform in the predetermined direction range. In addition, it is preferable that a light guide part is arrange | positioned so that the circumference | surroundings of a dome-shaped enclosure member may be enclosed, for example.

  The said structure of this invention WHEREIN: It is preferable that the said output surface of the said optical member is a spherical shape or aspherical shape convex outward.

  According to such a configuration, the optical member can be a spherical lens or an aspheric lens. For example, versatility can be improved as a spherical lens, and various aberrations can be reduced as an aspheric lens.

  The said structure of this invention WHEREIN: While the light guide part of the said optical member is formed in an annular | circular shape provided with an outer peripheral surface and an internal peripheral surface, it is preferable that the cross section along radial direction is wedge shape.

  With such a configuration, light can be repeatedly reflected between the outer peripheral surface and the inner peripheral surface in the wedge-shaped light guide, and the light can be guided to the exit surface side of the optical member.

  In the configuration of the present invention, the optical member is formed in a substantially cylindrical shape from the incident surface to the exit surface, and has a small diameter portion having the smallest diameter on the side closer to the entrance surface than the exit surface of the optical member. It is preferable that the diameter increases from the small-diameter portion toward the emission surface.

  According to such a configuration, the outer peripheral surface of the optical member is a slope whose diameter increases toward the exit surface on the exit surface side from the small diameter portion, so that whether the light is guided by the light guide portion or not. First, it is possible to suppress the light traveling from the incident surface of the optical member toward the exit surface from reaching the outer peripheral surface. In addition, when light reaches the outer peripheral surface of the optical member, it is possible to suppress a significant change in direction when reflected by the outer peripheral surface. That is, it is possible to suppress the light distribution from spreading more than when the optical member has a cylindrical shape whose diameter does not change.

In the configuration of the present invention, the lens effect package is provided on a base member,
It is preferable that the optical member includes a cylindrical base portion that accommodates the lens effect package from the outside of the light guide portion on the incident surface to the base member in a state of surrounding the lens effect package.

  According to such a structure, it becomes possible to attach an optical member to a base member corresponding to a lens effect package (light emitting device) by a base. At this time, since the light emitting device is disposed in the base, when light from the encapsulating resin of the light emitting device passes through the base member side from the light guide, it can be reflected by the base and directed toward the light guide. . In this case, the incident angle of light from the inside of the base to the outer peripheral surface of the base increases, and the amount of transmitted light appears to increase. However, if the diameter of the optical member is sufficiently small, the outer peripheral surface is increased in the circumferential direction. It functions as an inclined slope, and more light is reflected inside the outer peripheral surface. Moreover, you may provide a reflecting film in the outer periphery of an optical member.

  Moreover, in the said structure of this invention, the length of the diameter of the edge part by the side of the said output surface of the said substantially cylindrical optical member is longer than the length from the said output surface to the said base part along the axial direction of the said optical member. Short is preferred.

  According to such a configuration, it is possible to reduce the size of the light projection device by reducing the diameter, but by providing a light guide unit at this time, a large amount of light is provided on the outer peripheral surface side of the optical member having a small diameter. Can be suppressed. That is, the diameter of the optical member can be reduced by the light guide unit.

Further, in the above configuration of the present invention, the lens effect package is provided in a dome shape having an optical axis through which the enclosing member passes the apex,
The optical member has a rotationally symmetric shape having a symmetry axis;
It is preferable that the optical axis of the lens effect package and the symmetry axis of the optical member coincide.

In the configuration of the present invention, it is preferable that a reflective film is provided on the outer peripheral surface of the optical member.
According to such a configuration, regardless of the shape and refractive index of the optical member, the light can be reflected when the light inside the optical member reaches the outer peripheral surface, and the light traveling in a predetermined direction can be increased. .

  According to the present invention, the light distribution of the light projection device can be made narrow and the size of the light projection device can be reduced.

It is a figure for demonstrating the optical projector of embodiment of this invention. It is a figure for demonstrating an optical member similarly. It is a figure for demonstrating an optical member similarly. It is an orthogonal coordinate which shows the light distribution of the light projector of an Example similarly. It is a figure for demonstrating the irradiation intensity distribution of the light projector of an Example, (a) shows distribution on a plane, (b) has shown distribution by the orthogonal coordinate system.

Hereinafter, embodiments of the present invention will be described with reference to the drawings.
The light projection device according to the present embodiment is provided in a car, for example, projects infrared light, and the reflected light of the projected light is detected by a sensor provided in the car, so that it is around the car. It is used to grasp the outline of a certain object and measure the distance to the object.

  As shown in FIG. 1, the optical projection device 1 includes a base member 2 that is a base of the optical projection device 1, a light emitting device 10 that generates light, and an optical member 20 that is an optical element that refracts light. Yes. 1 to 3 show the light emitting device 10 through the front side portion of the optical member 20 of the light projection device 1 in FIGS. 1 to 3 so that the inside of the light projection device 1 can be easily understood.

The base member 2 is a plate-like member to which the light projection apparatus main body excluding the base member 2 is attached.
A light emitting device (lens effect package) 10 includes a substrate 11 that is a square plate, an LED element 12 provided on the substrate 11, a dome-shaped encapsulating resin 13 having a lens effect, and the substrate 11 as a base member. 2 and an attachment member 14 for attachment to 2. The LED element 12 is an infrared LED that emits infrared light from a light emitting surface, and has an emission wavelength of about 940 nm + −60 nm, for example. The encapsulating resin 13 is a transparent resin member having a lens effect, but may be glass instead of the resin.

The LED element 12 is provided at the center of one surface of the square plate-like substrate 11. The shape of the LED element 12 is a square plate shape. Further, the light from the LED element 12 is emitted around a direction perpendicular to the substrate 11 (a direction parallel to the optical axis direction of the optical member 20). The substrate 11 of the light emitting device 10 is attached to one surface of the base member 2 by a frame-like attachment member 14.
A dome-shaped encapsulating resin 13 is provided on the surface of the substrate 11 on the LED element 12 side so as to cover the LED element 12. The optical member 20 has a rotationally symmetric shape having a symmetry axis, and the optical axis of the lens effect package (light emitting device 10) and the symmetry axis of the optical member 20 coincide.
The optical axis of the dome-shaped encapsulating resin 13 passes through the apex of the dome-shaped encapsulating resin 13 and coincides with the central axis of light emission from the LED element 12. Further, the optical axis of the optical member 20 is also arranged so as to coincide with the central axis of light emission from the LED element 12. That is, the optical axis of the encapsulating resin 13, the central axis of light emission of the LED element 12, and the optical axis of the optical member 20 are in agreement.
Since the light emitted from the light emitting surface of the LED element 12 passes through the encapsulating resin 13 of the light emitting device 10, an annular portion excluding the central portion of the encapsulating resin 13 due to reflection or refraction at the boundary surface between the encapsulating resin 13 and the outside air, etc. Behaves like a light source (pseudo light source) in a pseudo manner. That is, the light-emitting device 10 including the LED element 12 and the encapsulating resin 13 behaves as if it has two types of light sources, that is, the LED element 12 (light source) and a pseudo light source using the encapsulating resin 13. The generated pseudo light source is not limited to one, and a plurality of positions are generated depending on the positional relationship between the light emitting surface of the LED element 12 and the encapsulating resin 13 and the shape of the encapsulating resin 13. It is not limited to the part. If the direction of the light from the pseudo light source is significantly different from the optical axis direction of the optical member 20, for example, the light from the pseudo light source does not enter an incident surface 29 described later of the optical member 20 or from the optical member 20. The emission direction deviates from the predetermined direction range. That is, there is a possibility that the light distribution becomes wide or the light distribution in a predetermined range is not substantially uniform.

On the other hand, the optical member 20 suppresses the light distribution distribution of the light projection device 1 from becoming wide corresponding to both the light source and the pseudo light source, and prevents the light distribution distribution from becoming non-uniform.
The optical member 20 is a substantially columnar member, and has a cylindrical base portion 26 attached to the base member 2 so as to surround the light emitting device 10. The optical member 20 is provided on the base portion 26 and serves as an optical element for the light from the light emitting device 10. An optical member main body 28 that condenses the light of the light emitting device 10 by adjusting the direction and makes the light parallel. The base 26 is a cylindrical body that is attached to the base member 2 at right angles to the base member 2, and the light emitting device 10 is accommodated in the internal space 22. Further, the center axis of the cylindrical base portion 26 coincides with the center of the LED element 12 of the light emitting device 10. A substantially columnar optical member main body 28 is provided on the cylindrical base 26. The base 26 and the optical member main body 28 are arranged coaxially, and the outer diameter of the base 26 and the maximum diameter of the optical member main body 28 are equal.

The optical member body 28 includes, as optical elements, an incident surface 29 on which light of the light emitting device 10 is incident and an output surface 21 that emits light of the incident light emitting device 10. The incident surface 29 is, for example, a flat surface, but may be a convex or concave surface. The emission surface 21 is a convex surface, for example, a spherical shape, but may be an aspherical shape. An aspherical surface is a concept that basically includes all surfaces other than a spherical surface, but does not include a flat surface, and is a curved surface. An aspherical lens is a lens that includes such a curved surface as a refractive surface. Examples of aspheric surfaces include cylindrical surfaces, toric surfaces, symmetric aspheric surfaces, and asymmetric aspheric surfaces. Although the aspherical lens depends on its shape, various aberrations can be reduced as compared with the spherical lens.
Such an optical member body 28 functions as a convex lens. The diameter of the optical member body 28 varies depending on the axial position. In the optical member 20, the outer diameter of the base 26 and the emission surface 21 is the same, and the optical member 20 has the largest diameter. Further, the small diameter portion 23 having the smallest diameter is provided on the side from the incident surface 29 of the optical member main body 28 of the optical member 20 to the exit surface 21 and closer to the incident surface 29. Between the end of the base portion 26 on the optical member main body 28 side and the small diameter portion 23 of the optical member main body 28, the diameter decreases from the base portion 26 toward the small diameter portion 23, so that the outer peripheral surface 25 of this portion becomes smaller. Tapered surface. Further, the outer peripheral surface 24 from the small diameter portion 23 to the emission surface 21 of the optical member main body 28 has an outer diameter that increases from the small diameter portion 23 toward the emission surface 21, and becomes a tapered surface opposite to the outer peripheral surface 25. ing.

  The incident surface 29 of the optical member main body 28 has an annular shape so as to surround the encapsulating resin 13 (the portion from which the light from the light emitting device 10 is emitted) at a position inside the base portion 26 and outside the encapsulating resin 13 in the internal space 22. The light guide unit 27 is provided. The light guide unit 27 is arranged in an annular shape away from the outer peripheral surface of the round dome-shaped encapsulating resin 13, and the encapsulating resin 13 is arranged at the center of the light guide unit 27. In addition, the light guide 27 is provided on the outermost side of the incident surface 29 in the cylinder of the base 26, that is, immediately inside the base 26. The length of the light guide portion 27 along the axial direction of the optical member 20 is shorter than the axial length of the base portion 26 and shorter than the length from the incident surface 29 to the base member 2.

  The light guide unit 27 has an annular shape as a whole having an outer peripheral surface and an inner peripheral surface, and a cross section along the radial direction of the optical member 20 has a wedge shape (triangular shape). As the distance from the base member 2 increases, the thickness decreases. Further, in the cross section of the light guide portion 27, the outer peripheral side of the light guide portion 27 is a tapered surface whose diameter decreases as the distance from the incident surface 29 increases. On the other hand, the inner peripheral side of the light guide 27 is substantially parallel to the axial direction of the optical member 20 in the cross section of the light guide 27. In such an optical member 20, as shown in FIG. 1, the length that is the diameter of the emission surface 21 that is the largest diameter, that is, the length D that is the outer diameter of the base portion 26 is the axial direction of the optical member 20. It is smaller than the length L along. The optical member 20 is provided with reflection films on the outer peripheral surfaces of both the base 26 and the optical member main body 28. The reflective film is, for example, deposited by depositing a metal such as aluminum or an alloy, but may be a plated metal or a paint having a metallic luster.

The main light paths in the light projection apparatus 1 will be described with reference to FIGS.
FIG. 2 shows a typical path in the light projection apparatus 1 for light emitted from substantially the center of the LED element 12 as a light source. A typical path A of light shown in FIG. 2 is emitted from the LED element 12 as diffused light, but the angle deviation from the optical axis of the optical member 20 is small, and the light emitting device 10 enters the incident surface 29 of the optical member 20. Will it refract so as to approach the optical axis direction of the optical member 20, reach the exit surface 21 without hitting the outer peripheral surface of the optical member body 28, and refract at the exit surface 21 and approach parallel light along the optical axis? , Tend to concentrate. That is, in the path A, light enters and exits the optical member 20 as a convex lens, light is refracted by the entrance surface 29 and the exit surface 21, and light travels from the outer peripheral surface of the optical member 20. It is not emitted or reflected from the outer peripheral surface.

  In the path B in which the angle when emitted from the light emitting device 10 is shifted from the optical axis direction than the path A, the angle of the light incident from the incident surface 29 of the optical member main body 28 is smaller than the small diameter portion 23 of the cross section of the optical member main body 28. It is inclined from the angle of the outer peripheral surface 24 on the emission surface 21 side. In this path B, the light hits the outer peripheral surface 24 but is in the range of total reflection, and the deviation of the angle of the reflected light with respect to the optical axis direction is small, and basically refracted at the exit surface 21 as in the case of the path A. The light is emitted in the direction of the predetermined direction range set as described above.

  In the path C in which the angle at the time of emission from the light emitting device 10 is shifted from the optical axis direction rather than the path B and directly enters the light guide unit 27, the light emitted from the LED element 12 is obliquely directed to the incident surface 29, and the incident surface 29 or toward the outer side of the incident surface 29 slightly. At this time, the light guide portion 27 extends from the outer peripheral portion in the incident surface 29, and the light from the LED element 12 enters the light guide portion 27 from the inner peripheral surface of the annular light guide portion 27. . At this time, the light is refracted and hits the outer peripheral surface of the light guide portion 27 inclined as described above in a state where the inclination angle with respect to the optical axis direction is small. In this case, the light is reflected and then the inner periphery The light is reflected by the surface, reaches the inside of the optical member body 28 on the exit surface 21 side from the entrance surface 29, and the light of the path C exits from the exit surface 21. In this case, the light emitted from the LED element 12 is incident on the light guide unit 27, so that the light repeatedly reflected in the light guide unit 27 is guided to the emission surface 21 side. It should be noted that some of the rays in the path C may take a light path reflected by the outer peripheral surface 24.

  In the path D in which the angle when emitted from the light emitting device 10 is shifted from the optical axis direction rather than the path C and does not directly enter the light guide unit 27, the light emitted from the LED element 12 does not go to the incident surface 29, and Head to the inner surface. At this time, the light does not strike the light guide portion 27, passes through between the light guide portion 27 and the base member 2, enters the base portion 26 from the inner peripheral surface of the base portion 26, and is refracted and has a large incident on the outer peripheral surface. Although it is incident at an angle, a reflection film is formed on the outer peripheral surface, so that light is reflected from the outer peripheral surface of the base portion 26 toward the inner peripheral surface, and the light hitting the inner peripheral surface is directed to the light guide portion 27. Incident from the light guide 27. Thus, the light reaching the light guide unit 27 is repeatedly reflected by the light guide unit 27 and guided to the exit surface 21 side.

  FIG. 3 shows a typical path in the light projection device 1 of light emitted from the pseudo light source at the outer peripheral portion of the encapsulating resin 13 of the light emitting device 10. In this embodiment, the pseudo light source is the surface of the dome-shaped encapsulating resin 13 and is generated in a donut shape outside the apex of the dome. Characteristic paths of the donut-like pseudo light source are shown as a path E and a path F. Other paths from the donut-like pseudo light source, such as the path toward the incident surface 29, can be identified with the path of the light beam directly emitted from the light emitting device 10, and thus will be omitted. In the path E, the light emitted from the doughnut-shaped pseudo light source of the encapsulating resin 13 enters the light guide section 27 toward the inner peripheral surface of the light guide section 27, and the light guide section 27 is the same as the path C described above. The light guided to is repeatedly reflected by the light guide unit 27 and travels toward the exit surface. In the path F, light emitted from the doughnut-shaped pseudo light source of the encapsulating resin 13 enters the light guide 27 toward the inner peripheral surface of the light guide 27 and is guided to the light guide 27. Is reflected once by the outer peripheral surface of the light guide portion 27 but then refracted and emitted without being reflected by the inner peripheral surface of the light guide portion 27, and this light is refracted and incident from the incident surface 29. In this case, refraction when entering the light guide portion 27 from the inner peripheral surface, one reflection on the outer peripheral surface of the light guide portion 27, and refraction upon emission from the inner peripheral surface of the light guide portion 27. The light incident on the light guide 27 can be guided to the exit surface 21 without being repeatedly reflected by the light guide 27 due to refraction upon incidence from the incident surface 29.

  According to such an optical projection device 1, the light emitted from the light emitting device 10 can be directed more in a predetermined direction range by the optical member 20 having the light guide portion 27. In particular, even if the encapsulating resin 13 is used in the light emitting device 10 to generate a pseudo light source, and more light deviates from the optical axis direction (axial direction) of the optical member 20, more light is directed within a predetermined direction range. Can do. As a result, the light projector 1 can be made narrowly distributed, and the light within the predetermined direction range can be made more uniform.

  In this embodiment, a dome-shaped encapsulating resin having one optical axis passing through the vertex from the center of the LED element 12 is used. However, the resin has a plurality of optical axes passing through the vertex from the center of the LED element 12. It may be a lens effect package using a shaped encapsulating resin. The light emitting device 10 may have no encapsulating resin (encapsulating member) 13. Further, the light emitting device 10 may use, for example, an LED with a lens such as a chip LED with a lens or a bullet-type LED. Further, the LED element 12 is not limited to one that emits infrared light, and may be an LED element having a wavelength of visible light or ultraviolet light. Further, when the vertical and horizontal lengths of the substrate 11 of the light emitting device 10 are 4 mm or less, the axial length L of the optical member 20 is 7 mm or less, and the maximum diameter of the optical member 20 is 6.5 mm or less. preferable.

Examples of the optical projection apparatus of the present invention will be described below.
The optical projection apparatus 1 of this embodiment has the shape shown in FIG. 1 and is a length D along the axial direction of the optical projection apparatus 1 (the axial length of the optical member 20 and the thickness of the base member 2). Is 7 mm, and the maximum outer diameter D of the optical projection device 1 (optical member 20) is 6.5 mm. The lens effect package (light emitting device 10) is the same as the conventional one, and the length of one side of the substrate (square) is 3.95 mm.
The light emitting device 10 has an LED emission wavelength of 950 nm, a radiant flux of 1.07 W, and a directivity angle half width (FWHM: half angle) of ± 45 degrees.
The material of the optical member 20 is, for example, polycarbonate, but other resins such as a cycloolefin copolymer can also be used.

Below, the simulation result of the projection of the light of the light-emitting device 10 in the light projector 1 is demonstrated.
4 shows the light distribution (Rectangular Candela Distribution Plot) of the orthogonal coordinate system of the light projection apparatus 1, the vertical axis shows the radiation intensity (W / sr: steradian per watt), and the horizontal axis shows the angle ( degree)). As shown in FIG. 4, the half width of the directivity angle is ± 23 degrees.
FIG. 5 is a plot of irradiance (w / m ² ) at a position 500 mm away from the light projector 1 in a range of 2000 mm × 2000 mm, and one pixel is 1 mm × 1 mm. FIG. 5 (a) shows the irradiance (w / m ² ) in shades on a plane, and FIG. 5 (b) shows the irradiance (w / m ² ) on the vertical axis and the horizontal axis. Is the position (mm), for example, the position on the horizontal axis in FIG. The emission efficiency in the simulation was 74%. The maximum value of the irradiance is 8.6 W / m ² in areal extent of 0.000001M ^2, the radiation intensity of the average in the area range of 0.16 m ^2, surrounded by a square in FIG. 5 (b) is It was 3.5 W / m ² .

DESCRIPTION OF SYMBOLS 1 Light projector 2 Base member 10 Light-emitting device (lens effect package)
12 LED element 13 Encapsulation resin (encapsulation member)
20 Optical member 21 Output surface 23 Small diameter portion 26 Base portion 27 Light guide portion 29 Incident surface

Claims (8)

A lens effect package including an LED element encapsulated in an encapsulating member on an LED substrate; and an optical member that arranges and projects the direction of light from the lens effect package,
The optical member includes an incident surface on which light from the lens effect package is incident, and an output surface from which incident light is emitted.
The optical member extends on the incident surface so as to surround a periphery of a portion where the light of the lens effect package is emitted, and guides light incident from the lens effect package toward the emission surface. An optical projection device comprising a light guide.   The optical projection apparatus according to claim 1, wherein the emission surface of the optical member has an outwardly convex spherical shape or an aspherical shape.   The light guide portion of the optical member is formed in an annular shape having an outer peripheral surface and an inner peripheral surface, and a cross section along the radial direction is wedge-shaped. Light projection device.   The optical member is formed in a substantially cylindrical shape from the entrance surface to the exit surface, and a small-diameter portion having a smallest diameter is provided closer to the entrance surface than the exit surface of the optical member, and the small-diameter portion The optical projection device according to claim 1, wherein the diameter increases from the position toward the exit surface. The lens effect package is provided on a base member,
The optical member includes a cylindrical base portion that accommodates the lens effect package from the outside of the light guide portion on the incident surface to the base member in a state of surrounding the lens effect package. Item 5. The optical projection device according to any one of Items 1 to 4.   The length of the diameter of the end portion on the emission surface side of the substantially cylindrical optical member is shorter than the length from the emission surface to the base portion along the axial direction of the optical member. The light projection device described in 1. The lens effect package is provided in a dome shape with an optical axis passing through the apex of the enclosing member,
The optical member has a rotationally symmetric shape having a symmetry axis;
The optical projection apparatus according to claim 1, wherein the optical axis of the lens effect package and the symmetry axis of the optical member coincide with each other.   The optical projection apparatus according to claim 1, wherein a reflection film is provided on an outer peripheral surface of the optical member.

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