JP2019070847A - Cooling structure of illumination optical system and projection type display device - Google Patents

Abstract

To provide: a cooling structure of an illumination optical system that can improve cooling efficiency of a phosphor and prevent a reduction in illuminance of light emitted from the illumination optical system; and a projection type display device.SOLUTION: A cooling structure 11 of an illumination optical system of the present invention comprises: a phosphor member 12 having a phosphor layer 12b that emits fluorescence upon irradiation of excitation light from a light source 7; a duct 16 that partitions between an internal space where the phosphor member 12 is arranged and an external space, and guides a cooling air to the phosphor member 12; a cooling member 21 that is provided downstream of the phosphor member 12 in the duct 16 and cools the cooling air; and a heat radiation member 24 that is arranged outside the duct 16. The cooling member 21 has a heat receiving unit 21a that is arranged inside the duct 16, and a cooling unit 21b that is connected to the heat receiving unit 21a and arranged outside the duct 16. There is provided, outside the duct 16, a fan 27 for heat radiation sending the cooling air to the heat radiation member 24 and cooling unit 21b.SELECTED DRAWING: Figure 7

Description

  The present invention relates to a cooling structure of an illumination optical system using a phosphor, and a projection type display apparatus.

  In recent years, an illumination optical system provided with a phosphor that emits fluorescence upon irradiation with excitation light has been proposed. This type of illumination optical system is used, for example, in a projection display apparatus. FIG. 1 shows a perspective view of a projection type display provided with an illumination optical system related to the present invention. FIG. 2 shows a perspective view of an illumination optical system related to the present invention. FIG. 3 shows a plan view of an illumination optical system related to the present invention.

  As shown in FIG. 1, a projection display apparatus 101 related to the present invention includes an illumination optical system 103 and an image generation optical system 104 to which light from the illumination optical system 103 is incident. As shown in FIGS. 2 and 3, the illumination optical system 103 comprises a laser light source 107 and a phosphor wheel 112 provided with a phosphor layer to which the laser light emitted from the laser light source 107 is irradiated. There is.

  Patent Document 1 discloses an illumination optical system including such a phosphor wheel. Patent Document 1 discloses an illumination optical system including a phosphor unit having a phosphor wheel and a motor for rotating the phosphor wheel.

  The phosphor wheel disclosed in Patent Document 1 has a substrate rotatably provided about a rotation axis orthogonal to one surface. A phosphor region and a reflection region are formed on one surface of the substrate. The phosphor region has a phosphor layer that emits fluorescence of a predetermined wavelength upon irradiation with laser light. The reflection area is an area that reflects laser light. The irradiated laser light of the phosphor wheel is repeatedly irradiated to the phosphor area and the reflection area of the rotating phosphor wheel. Thereby, the fluorescence emitted from the phosphor and the laser light reflected by the reflection area are sequentially emitted from the phosphor wheel.

  The illuminance of light emitted from such an illumination optical system depends on the amount of fluorescence generated from the phosphor. The phosphor generates heat as it is irradiated with the laser light, and has a characteristic that the light emission efficiency is reduced by the heat generation. Therefore, in order to prevent the decrease in the illuminance of the light emitted from the illumination optical system, it is necessary to suppress the heat generation of the phosphor.

  Patent Document 2 discloses a configuration having a phosphor wheel in which a recess is formed in a phosphor layer, and a fan for blowing a cooling air toward the recess of the phosphor wheel. In the configuration disclosed in Patent Document 2, a turbulent flow is generated by blowing a cooling air to the recess of the phosphor wheel, and the cooling efficiency of the phosphor is enhanced using the effect of heat diffusion.

WO 2012/127554 pamphlet JP 2012-78707 A JP 2013-25249 A

  In the illumination optical system described in Patent Document 1 described above, the phosphor is cooled by the flow of air around the phosphor wheel that the phosphor wheel itself receives when the phosphor wheel rotates. For this reason, the illumination optical system described in Patent Document 1 is poor in the cooling effect of cooling the phosphor.

  In the configuration disclosed in Patent Document 2, the cooling air is locally blown toward the laser light irradiated portion in the phosphor layer of the phosphor wheel. In the configuration described in Patent Document 2 as described above, the cooling effect of the phosphor is still insufficient, and it is desired to further improve the cooling efficiency.

  Further, Patent Document 3 discloses a configuration in which a fan for supplying cooling air to one surface side of a phosphor wheel on which a phosphor layer is formed is disposed in the vicinity of the phosphor wheel. However, in an illumination optical system using a phosphor wheel, a condenser lens for condensing the fluorescence emitted from the phosphor layer is disposed adjacent to the phosphor layer. Therefore, the flow of the cooling air is blocked by being blown to the lens holder holding the condenser lens, and it is difficult to flow the cooling air sufficiently on one surface of the phosphor wheel. As described above, in the configuration described in Patent Document 3, the cooling air is sent only to one surface side of the phosphor wheel, and the flow of the cooling air is blocked by the lens holder, so that the cooling efficiency of the phosphor is low. There is.

  In addition, in general, in the illumination optical system using a laser light source, as shown in FIGS. 2 and 3, the laser light leaks to the outside of the illumination optical system 103 from other than the lens 111 from which light is emitted from the illumination optical system 103. It is covered by the cover 110 so as not to be. Therefore, the illumination optical system 103 has a closed structure from the outside. For this reason, in the illumination optical system 103 using the laser light source 107, the ambient temperature inside the cover 110 tends to rise, and the air inside the cover 110 is easily warmed by the heat generated by the laser light source 107 and becomes high temperature. As a result, the ambient air received by the phosphor wheel 112 itself disposed inside the cover 110 is also in a high temperature state, so there is a problem that the cooling efficiency of the phosphor is low.

  Therefore, in the illumination optical system related to the present invention described above, since the cooling efficiency of the phosphor is low, the temperature of the phosphor tends to rise, and the illuminance of light emitted from the illumination optical system decreases. As a result, there is a problem that the maintenance factor of the illuminance decreases with the continuous use time of the illumination optical system.

  Therefore, the present invention has an object of providing a cooling structure of an illumination optical system and a projection type display device capable of enhancing the cooling efficiency of a phosphor and preventing the decrease in the illuminance of light emitted from the illumination optical system. .

  In order to achieve the above-mentioned object, the cooling structure of the illumination optical system according to the present invention comprises a phosphor member having a phosphor layer emitting fluorescence by excitation light emitted from a light source, and an internal space in which the phosphor member is disposed. And a duct for guiding the cooling air to the phosphor member, a cooling member provided on the downstream side of the phosphor member of the duct for cooling the cooling air, and a heat dissipating member disposed outside the duct And the cooling member includes a heat receiving unit disposed inside the duct, and a cooling unit connected to the heat receiving unit and disposed outside the duct, and the heat radiation member and the cooling are provided outside the duct. A fan for radiating heat that sends cooling air to the part is provided.

  Further, a projection type display apparatus according to the present invention includes an illumination optical system including a cooling structure of the illumination optical system, and an image generation optical system including an image element for modulating light emitted from the illumination optical system according to an image signal. And.

  According to the present invention, it is possible to enhance the cooling efficiency of the phosphor and to prevent the decrease in the illuminance of the light emitted from the illumination optical system.

It is a perspective view showing a projection type display provided with an illumination optical system relevant to the present invention. It is a perspective view which shows the illumination optical system relevant to this invention. It is a top view which shows the illumination optical system relevant to this invention. FIG. 1 is a perspective view showing a projection display according to a first embodiment as seen through. It is a perspective view which shows the illumination optical system with which the projection type display apparatus of 1st Embodiment is provided. It is a perspective view shown in order to demonstrate the cooling structure of the illumination optical system of 1st Embodiment. It is a top view which shows the cooling structure of the illumination optical system of 1st Embodiment. It is a top view which expands and shows the cooling structure of the illumination optical system of 1st Embodiment. It is a perspective view which expands and shows the duct and lens holder which the cooling structure of the illumination optical system of a 1st embodiment has. It is a perspective view shown in order to demonstrate the cooling structure of the illumination optical system of 2nd Embodiment. It is a top view which shows the cooling structure of the illumination optical system of 2nd Embodiment. It is a top view which expands and shows the cooling structure of the illumination optical system of 2nd Embodiment. It is a perspective view which shows the duct and lens holder which the cooling structure of the illumination optical system of 2nd Embodiment has.

  Hereinafter, specific embodiments of the present invention will be described with reference to the drawings.

First Embodiment
FIG. 4 is a perspective view of the projection display apparatus according to the first embodiment. FIG. 5 shows a perspective view of an illumination optical system provided in the projection type display device of the first embodiment. FIG. 6 is a perspective view for explaining the cooling structure of the illumination optical system of the first embodiment. FIG. 7 shows a plan view of the cooling structure of the illumination optical system of the first embodiment.

  As shown in FIGS. 4 and 5, in the projection type display apparatus 1 according to the first embodiment, light is incident from the illumination optical system 3 using the fluorescent substance and the illumination optical system 3 and is projected on the projection surface And an image generation optical system 4 for generating an image.

  As shown in FIGS. 6 and 7, the illumination optical system 3 includes a first laser light source 6 and a second laser light source 7 which emit laser light, and a first of the laser light emitted from the first laser light source 6. A first optical component group constituting an optical path and a second optical component group constituting a second optical path of the laser light emitted from the second laser light source 7 are provided. The illumination optical system 3 further includes a cover 10 covering the entire first optical path and covering the entire second optical path including the optical path from the second laser light source 7 to the phosphor wheel 12.

  The first and second laser light sources 6, 7 have a plurality of laser diodes 8 for emitting blue laser light having a blue wavelength, as shown in FIG. Are arranged. The first and second laser light sources 6 and 7 are not limited to those emitting blue laser light. As the first and second laser light sources 6 and 7, those emitting light of other wavelengths such as ultraviolet light may be used. The first and second optical component groups will be described later. The cover 10 is configured by combining a pair of upper cover 10a and lower cover 10b.

  As shown in FIG. 6, the second optical path condenses the fluorescent light emitted from the fluorescent material wheel 12 and the fluorescent material wheel 12 that emits fluorescence by the irradiation of the laser light emitted from the second laser light source 7. And a plurality of focusing lenses 13a, 13b and 13c. The illumination optical system 3 is provided with a cooling structure 11 for cooling the phosphor wheel 12.

  FIG. 8 is an enlarged plan view of the cooling structure 11 of the illumination optical system of the first embodiment. FIG. 9 is an enlarged perspective view of a duct and a lens holder of the cooling structure 11 of the illumination optical system of the first embodiment.

  As shown in FIGS. 7 and 8, the cooling structure 11 of the illumination optical system according to the first embodiment includes a phosphor layer 12b that emits fluorescence by laser light as excitation light emitted from the second laser light source 7. The cooling air sent from the fan 15 is divided between an external space and a phosphor wheel 12 as a phosphor member, a fan 15 for sending cooling air to the phosphor wheel 12, and an inner space where the phosphor wheel 12 is disposed And a duct 16 for guiding the phosphor wheel 12 to the phosphor wheel 12.

  The phosphor wheel 12 comprises a substrate 12a on which a phosphor layer 12b is formed, as shown in FIG. The substrate 12a is attached to the rotation shaft 17a of the wheel motor 17, and is configured to be rotatable around a rotation shaft 17a parallel to the direction orthogonal to the main surface of the substrate 12a. The wheel motor 17 is mounted on the bottom plate of the lower cover 10b. The phosphor layer 12 b is formed by applying a phosphor on a circular substrate 12 a. The phosphor emits yellow fluorescence with a wavelength band ranging from the green wavelength to the red wavelength.

  In addition, although the fluorescent substance wheel 12 of this embodiment was comprised so that only yellow light could be emitted, it is not limited to this. As the phosphor wheel 12, the phosphor layer may be divided so as to emit fluorescence of different colors according to the irradiation position of the laser light in the phosphor layer.

  By using the phosphor wheel 12, since the irradiation position of the laser light is changed along with the rotation of the phosphor wheel 12, it is possible to suppress the occurrence of the temperature deviation of the phosphor in each part of the phosphor layer 12b. For this reason, it is suppressed that the conversion efficiency to fluorescence falls in a part of fluorescent substance layer 12b, and it can be made easy to obtain fluorescence stably.

  The fan 15 is disposed inside the cover 10. A sirocco fan is used as the fan 15 and has a blower port for sending a cooling air.

  As shown in FIG. 6 and FIG. 7, the duct 16 is disposed inside the cover 10 so as to send the cooling air sent from the fan 15 in a direction orthogonal to the rotation shaft 17 a of the wheel motor 17. The partition wall 19 is extended to the The dividing wall 19 is formed on the bottom plate of the lower cover 10b along the side plate of the lower cover 10b. The duct 16 is constituted by the partition wall 19, the top plate of the upper cover 10 a, the bottom plate and the side plate of the lower cover 10 b, and is provided inside the cover 10. Thus, the duct 16 has an internal space closed by the partition wall 19, the top plate of the upper cover 10 a, the bottom plate and the side plate of the lower cover 10 b, and the internal space is the cooling air sent from the fan 15. It is configured as a flow path of

  As shown in FIG. 9, at one end of the duct 16, an opening 16 a connected to the air blowing port of the fan 15 is provided. Further, as shown in FIG. 7, at the other end of the duct 16 on the downstream side of the phosphor wheel 12, a heat exchanger 21 as a cooling member for cooling the cooling air is provided. The heat exchanger 21 cools the cooling air after passing through the phosphor wheel 12. Further, as shown in FIG. 7, the cross-sectional area of the flow path is expanded at the other end of the duct 16. By expanding the cross-sectional area of the flow path at the other end of the duct 16, the amount of cooling air blown to the heat exchanger 21 is increased.

  As shown in FIGS. 6 and 7, the heat exchanger 21 includes a heat receiving portion 21 a disposed inside the other end of the duct 16, a cooling portion 21 b disposed outside the duct 16, and a heat receiving portion 21 a. And a heat transfer unit 21c for transferring heat to the cooling unit 21b. The heat exchanger 21 cools the phosphor wheel 12 by removing heat from the warm air. Thus, by arranging the heat exchanger 21 in the duct 16, it becomes possible to circulate the cooling air cooled by the heat exchanger 21 to the fan 15, and fluorescence using the cooling air sent from the fan 15 The cooling efficiency of the body is enhanced. In addition, as a heat exchanger, the cooling mechanism of the liquid cooling system which circulates a liquid and cools may be used.

  As shown in FIG. 8, a phosphor wheel 12 and a wheel motor 17 are disposed inside the duct 16. In the duct 16, a lens holder 22 for holding a plurality of focusing lenses 13a, 13b and 13c and a plurality of focusing lenses 13a, 13b and 13c is the phosphor layer 12b of the phosphor wheel 12. It is provided adjacent to the formed surface.

  As shown in FIGS. 8 and 9, the lens holder 22 has a holding portion 22a for holding the outer peripheral portion of each of the condensing lenses 13a, 13b, 13c, and a base portion 22b for supporting the holding portion 22a. .

  The base 22b of the lens holder 22 is formed in a plate shape having an L-shaped cross section, and is fixed on the bottom plate of the lower cover 10b. The base 22b has a rising wall 22c. The holding portion 22a is provided at a position away from the bottom plate of the lower cover 10b of the rising wall 22c. The rising wall 22 c is aligned with and connected to the partition 19 of the duct 16 and is configured as a part of the partition 19.

  As described above, by the lens holder 22 being configured, the first air flow path 23a through which the cooling air flows is secured between the holding portion 22a and the bottom plate of the lower cover 10b, and the air flow of the cooling air is ensured. Sex is enhanced. This prevents the cooling air sent from the fan 15 from being blocked by the lens holder 22 and allows the cooling air to flow smoothly along the dividing wall 19 of the duct 16.

  The holding portion 22a of the lens holder 22 holds the outer peripheral portion of each of the condensing lenses 13a, 13b and 13c. The holding portion 22a has a plurality of second air passages 23b through which the cooling air sent from the fan 15 passes between the condenser lenses 13a, 13b and 13c. The holding portion 22a is capable of efficiently cooling the phosphor layer 12b without interrupting the flow of the cooling air sent from the fan 15 by having the second air passage 23b.

  Further, as shown in FIG. 7 and FIG. 8, a heat sink 24 as a heat dissipation member for radiating the heat transferred from the rotating shaft 17 a to the outside of the duct 16 is provided outside the duct 16.

  A heat sink 24 is connected to a bearing portion 17 b of the rotation shaft 17 a of the wheel motor 17. As shown in FIG. 8, a thermally conductive sheet 25 is sandwiched between the bearing portion 17 b and the heat sink 24, and the heat is transmitted from the bearing portion 17 b to the heat sink 24 via the thermally conductive sheet 25. Heat is released. Thus, by using the heat sink 24, the cooling effect of the phosphors of the phosphor wheel 12 is enhanced. As a modification, instead of the structure in which the heat conduction sheet 25 is in contact with the bearing portion 17b, the heat conduction sheet 25 may be in direct contact with the rotation shaft 17a.

  Further, as shown in FIG. 6 and FIG. 7, another fan 27 for sending cooling air to the heat sink 24 and the cooling portion 21 b of the heat exchanger 21 is provided outside the cover 10 which is the outside of the duct 16. . The heat sink 24 and the cooling unit 21 c are disposed outside the duct 16 so as to face each other.

  A propeller fan is used as the fan 27. As shown in FIG. 4, the projection display apparatus 1 of the present embodiment includes a housing 9 in which the illumination optical system 3 is provided, and the inside of the housing 9 is located at a position facing the cooling unit 21 b. , Fan 27 is arranged.

  The cooling air sent from the fan 27 cools the cooling unit 21b, and then is blown to the heat sink 24 through the cooling unit 21b. As a result, the cooling portion 21b and the heat sink 24 can be efficiently cooled using the cooling air sent from one fan 27, and the cooling structure 11 is simplified.

  In the present embodiment, the cooling air that has passed through the cooling portion 21 b of the heat exchanger 21 is blown to the heat sink 24, but the present invention is not limited to this configuration. Of course, as a modification, the cooling air passing through the heat sink 24 may be blown to the cooling unit 21 b or the cooling air may be flowed between the heat sink 24 and the cooling unit 21 b. .

  In the first optical path of the illumination optical system 3, as shown in FIGS. 6 and 7, the laser light emitted from the laser diode 8 of the first laser light source 6 is condensed by the condensing lens 31. The light condensed by the condensing lens 31 is condensed by the condensing lens 32 toward the diffusion plate 33. The laser light that has entered the diffusion plate 33 is diffused and enters the condensing lens 34. The light incident on the condenser lens 34 is incident on the dichroic mirror 35. The dichroic mirror 35 transmits light having a blue wavelength and reflects light having a wavelength longer than the green wavelength. Therefore, the dichroic mirror 35 transmits the blue laser light emitted from the first laser light source 6 and reflects the yellow light emitted from the phosphor layer 12 b of the phosphor wheel 12 described above. The yellow light reflected by the dichroic mirror 35 and the blue laser light transmitted through the dichroic mirror 35 enter the condensing lens 36 and are emitted from the illumination optical system 3. The light emitted from the illumination optical system 3 is incident on the image generation optical system 4.

  In the second optical path of the illumination optical system 3, as shown in FIGS. 6 and 7, the laser light emitted from the laser diode 8 of the second laser light source 7 is condensed by the condensing lens 41. The light collected by the collecting lens 41 is collected by the collecting lens 42 toward the diffusion plate 43. The light entering the diffusion plate 43 is diffused and enters the light tunnel 44. The light tunnel 44 is a hollow optical element, and the upper, lower, left, and right inner surfaces inside are configured as reflection mirrors. Light incident on the light tunnel 44 is reflected on the inner surface of the light tunnel 44 multiple times. As a result, the illuminance distribution of light at the exit of the light tunnel 44 is made uniform. Alternatively, a rod lens (rod integrator) may be used instead of the light tunnel 44.

  The light emitted from the light tunnel 44 is collected by the collecting lens 45. The light condensed by the condensing lens 45 enters the dichroic mirror 46. The dichroic mirror 46 reflects light having a blue wavelength and transmits light having a wavelength longer than the green wavelength. The blue laser light reflected by the dichroic mirror 46 passes through the condenser lenses 13 a, 13 b and 13 c and is irradiated to the phosphor layer 12 b of the phosphor wheel 12. The phosphor is excited by blue laser light and emits yellow fluorescence.

  The yellow light emitted from the phosphor is collected by the collection lenses 13 a, 13 b and 13 c, and enters the dichroic mirror 46. The yellow light incident on the dichroic mirror 46 is transmitted through the dichroic mirror 46 and incident on the condenser lens 47. The yellow light incident on the condenser lens 47 is incident on the dichroic mirror 35. The yellow light incident on the dichroic mirror 35 is reflected by the dichroic mirror 35 and is incident on the condenser lens 36.

  In the image generation optical system 4 included in the projection display apparatus 1, as shown in FIG. 4, the light emitted from the condenser lens 36 of the illumination optical system 3 enters the light tunnel 51. The light incident on the light tunnel 51 is reflected on the inner surface of the light tunnel 51 a plurality of times. As a result, the illuminance distribution of light at the output portion of the light tunnel 51 is made uniform. The light emitted from the light tunnel 51 is white light which is a combined light of yellow light and blue light. The white light passes through the condenser lenses 52 and 53 and is reflected by the mirror 54. The white light reflected by the mirror 54 passes through the condenser lens 55 and enters the TIR (internal total reflection) prism 56. The light entering the TIR prism 56 is totally internally reflected and enters the color prism 57. The color prism 57 splits white light into green light, red light and blue light.

  The light split by the color prism 57 is incident on a DMD (digital mirror device) as an image element that modulates the light according to an image signal. The green light split by the color prism 57 is incident on the DMD 58 for green light. Similarly, the red light split by the color prism 57 is incident on the DMD for red light (not shown), and the blue light split by the color prism 57 is incident on the DMD (not shown) for blue light . As a modification, a liquid crystal panel (LCD) may be used instead of the DMD as the image element.

  The DMD 58 has a large number of micromirrors arranged in a matrix, each micromirror corresponding to a pixel of the image to be projected. The angle of each micro mirror is configured to be adjustable. The light incident on the micro mirror having an angle is reflected toward the projection lens 59. Therefore, the green light, the red light and the blue light reflected by each DMD enter the color prism 57 and are synthesized by the color prism 57. The light combined by the color prism 57 is projected through the TIR prism 56 and the projection lens 59 onto a projection surface such as a screen.

  The operation of cooling the phosphor wheel 12 by the fan 15 and the duct 16 will be described for the cooling structure 11 of the illumination optical system configured as described above.

  The cooling air sent from the fan 15 flows in the duct 16 along the dividing wall 19 and is blown to both sides of the substrate 12 a of the phosphor wheel 12. The cooling air blown to the surface of the phosphor wheel 12 on the side of the phosphor layer 12b passes through the air passage 23 of the lens holder 22 and the space on the outer peripheral side of the holding portion 22a of the lens holder 22 and is on the phosphor layer 12b side Flow smoothly along the face of the Thus, the cooling air sent from the fan 15 is guided along the duct 16 to effectively cool the entire phosphor wheel 12.

  Further, the cooling air that has cooled the phosphor layer 12 b of the phosphor wheel 12 flows along the partition wall 19 and is cooled by the heat exchanger 21. The air cooled by the heat exchanger 21 is discharged from the duct 16 and circulates through the inside of the illumination optical system 3 to the fan 15 as shown by the arrow in FIG. Therefore, the fan 15 can send the cooling air cooled by the heat exchanger 21 to the phosphor wheel 12, and the cooling efficiency of the phosphor is enhanced.

  Further, the cooling unit 21 b of the heat exchanger 21 is cooled by the cooling air sent from the fan 27. The heat sink 24 is cooled by the cooling air that cools the cooling unit 21 b. The heat sink 24 is cooled, whereby the phosphor layer 12 b of the phosphor wheel 12 is cooled.

  In this embodiment, the air around the phosphor wheel 12 is guided by the cooling air guided along the duct 16 as compared with the configuration in which the fan is simply disposed in the vicinity of the phosphor wheel in the casing of the projection display device. Can be cooled. Thereby, the phosphor can be cooled efficiently.

  In addition, the lens holder 22 disposed in the duct 16 prevents the flow of the cooling air sent from the fan 15 from being disturbed by having the air passage 23. The cooling effect of the phosphors is enhanced by the synergetic effect of each component for enhancing the air permeability of the cooling air.

  As described above, the cooling structure 11 of the illumination optical system of the first embodiment includes the duct 16 that guides the cooling air sent from the fan 15 to the phosphor wheel 12. As a result, the cooling air guided along the duct 16 lowers the temperature of the air around the phosphor wheel 12 so that the phosphor can be cooled efficiently. As a result, the cooling structure 11 can enhance the cooling efficiency of the phosphor and prevent the decrease in the illuminance of the light emitted from the illumination optical system 3.

  In addition, the lens holder 22 has a space between the holding portion 22a and the bottom plate of the lower cover 10b, thereby preventing the flow of the cooling air sent from the fan 15 from being blocked, and the phosphor of the phosphor wheel 12 The cooling air can be sufficiently flowed to the surface on the layer 12 b side. Furthermore, the lens holder 22 prevents the flow of the cooling air sent from the fan 15 from being obstructed by the holding portion 22a having the air passage 23, and cooling is performed on the surface of the phosphor wheel 12 on the phosphor layer 12b side. It is possible to make the wind flow smoothly. As a result, the cooling effect of the phosphor can be enhanced.

  In addition, by providing the heat exchanger 21, the cooling structure 11 can prevent the temperature of the cooling air sent by the fan 15 from rising, and can cool the phosphor wheel 12 more efficiently. The cooling structure 11 can also release the heat of the phosphor wheel 12 to the outside of the duct 16 by providing the heat sink 24.

Second Embodiment
Next, the cooling structure of the second illumination optical system will be described. In the illumination optical system provided with the cooling structure of the second embodiment, for convenience of explanation, the same components as those of the illumination optical system of the first embodiment are given the same reference numerals as those of the first embodiment. I omit it.

  FIG. 10 is a perspective view for explaining the cooling structure of the illumination optical system of the second embodiment. FIG. 11 is a plan view of the cooling structure of the illumination optical system of the second embodiment. FIG. 12 shows an enlarged plan view of the cooling structure of the illumination optical system of the second embodiment. FIG. 13 shows a perspective view of a duct and a lens holder which the cooling structure of the illumination optical system of the second embodiment has.

  As shown in FIGS. 10 and 11, the cooling structure 61 of the illumination optical system of the second embodiment includes a duct 66 having a dividing wall 69 for dividing an internal space, and a duct 66 divided by the dividing wall 69. A first fan 67a and a second fan 67b for respectively sending cooling air to each space are provided.

  As shown in FIGS. 12 and 13, the interior space of the duct 66 is formed between the first and second fans 67a, 67b and the phosphor wheel 12 inside the duct 66, and one side of the substrate 12a. And a second space including the other surface of the substrate 12b. The dividing wall 69 is extended along the dividing wall 19 from one end of the duct 66 to a position adjacent to the phosphor wheel 12. As shown in FIG. 13, at one end of the duct 66, an opening 66a connected to the air outlet of the first fan 67a and an opening 66b connected to the air outlet of the second fan 67b are formed. .

  In the cooling structure 61 of the illumination optical system of the second embodiment configured as described above, the cooling air sent from the first fan 67 a is divided by the dividing wall 69 in the internal space of the duct 66. The light flows through the space, and is led to one surface side of the phosphor wheel 12 on which the phosphor layer 12 b is formed. Similarly, the cooling air sent from the second fan 67 b flows in the other space of the inner space of the duct 66 divided by the dividing wall 69 and is led to the other surface of the phosphor wheel 12. . As described above, in the present embodiment, the cooling air is smoothly guided to both sides of the phosphor wheel 12 respectively.

  According to the cooling structure 61 of the illumination optical system of the second embodiment, by providing the dividing wall 69 and the first and second fans 67a and 67b, cooling air is supplied to both sides of the phosphor wheel 12, respectively. It becomes possible to lead smoothly, and the cooling efficiency of the phosphor can be further enhanced.

  In addition, although the cooling structure of the illumination optical system according to the present invention is used for the illumination optical system including the phosphor wheel, it may be used for other illumination optical systems as needed. The present invention may be used, for example, in an illumination optical system using a color wheel having a color filter on which light from a light source is incident, and in other illumination optical systems using a phosphor of a fixed structure.

  Although the present invention has been described above with reference to the embodiments, the present invention is not limited to the above-described embodiments. The configuration and details of the present invention can be modified in various ways that can be understood by those skilled in the art within the scope of the present invention.

1 Projection display
3 Illumination optics
7 Second laser light source
11 Cooling structure
12 phosphor wheel
12a substrate 12b phosphor layer 15 fan
16 ducts
17a Rotation axis

Claims (6)

A phosphor member having a phosphor layer that emits fluorescence by excitation light emitted from a light source;
A duct for dividing an inner space in which the phosphor member is disposed from an outer space, and for guiding a cooling air to the phosphor member;
A cooling member provided on the downstream side of the phosphor member of the duct for cooling a cooling air;
A heat dissipation member disposed outside the duct;
Equipped with
The cooling member includes a heat receiving unit disposed inside the duct, and a cooling unit connected to the heat receiving unit and disposed outside the duct.
A cooling structure of an illumination optical system, wherein a fan for radiating heat that sends cooling air to the heat radiating member and the cooling unit is provided outside the duct. A cooling structure of the illumination optical system according to claim 1,
And a lens disposed in the duct and configured to collect fluorescence emitted from the phosphor layer, and a lens holder disposed adjacent to the phosphor member and configured to hold the lens.
A cooling structure of an illumination optical system, wherein a first air passage for passing the cooling air is provided between the lens holder and the phosphor member. The cooling structure of the illumination optical system according to claim 1 or 2,
The phosphor member comprises a substrate on which the phosphor layer is formed,
The cooling structure of the illumination optical system, wherein the substrate is configured to be rotatable. The cooling structure of the illumination optical system according to claim 3,
In the duct, there is provided a dividing wall which divides the internal space into a first space including one surface of the substrate and a second space including the other surface of the substrate. Optical system cooling structure. A cooling structure of the illumination optical system according to any one of claims 1 to 4, wherein
A cooling structure of an illumination optical system, comprising a heat dissipation member disposed outside the duct. An illumination optical system including the cooling structure of the illumination optical system according to any one of claims 1 to 5.
An image generation optical system including an image element that modulates light emitted from the illumination optical system in accordance with an image signal;

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