JP2008159415A - Light source device and projector - Google Patents

Abstract

The present invention provides a light source device capable of reducing a temperature change of a wavelength conversion element and supplying laser light with a high efficiency and a stable amount of light, and a projector using the light source device.
A light source unit that supplies laser light, a SHG element that is a wavelength conversion element that converts the wavelength of the laser light from the light source unit, and a wavelength conversion element that is fixed to a substrate using elastic force. Based on the measurement result by the temperature measurement unit and the thermistor 40 that is provided between the plate spring unit 13 that is the fixed unit, the temperature conversion unit that is provided between the wavelength conversion element and the fixed unit, and measures the temperature of the wavelength conversion element And a temperature adjustment unit that adjusts the temperature of the conversion element.
[Selection] Figure 5

Description

  The present invention relates to a light source device and a projector, and more particularly to a technology of a light source device that supplies laser light.

  Conventionally, in a light source device that supplies laser light, a wavelength conversion element, for example, a second-harmonic generation (SHG) element is used. By using the SHG element, for example, it is possible to supply laser light having a desired wavelength using a general-purpose laser that can be easily obtained. In the SHG element, it is known that when the refractive index distribution changes due to a temperature change, the phase matching condition is broken and the wavelength conversion efficiency is lowered. In order to supply a highly efficient and stable laser beam, it is desired to reduce the temperature change of the wavelength conversion element. For example, in the technique proposed in Patent Document 1, the influence of the ambient temperature is reduced by surrounding the wavelength conversion element using a member having a large thermal conductivity.

JP-A-6-301426

  The wavelength of the wavelength conversion element changes depending on the ambient temperature, and the temperature also changes by continuing to irradiate laser light. It is difficult to reduce the temperature change due to heat or the like generated inside the wavelength conversion element only by surrounding the wavelength conversion element with a member having a large thermal conductivity. In addition, when the ambient temperature fluctuates greatly, the influence on the wavelength conversion element may not be completely eliminated. As described above, according to the conventional technique, it is difficult to reduce the temperature change of the wavelength conversion element. The present invention has been made in view of the above-described problems, and a light source device capable of reducing a temperature change of a wavelength conversion element and supplying a laser beam with a high efficiency and a stable amount of light, and a projector using the light source device. The purpose is to provide.

  In order to solve the above-described problems and achieve the object, according to the present invention, a light source unit that supplies laser light, a wavelength conversion element that converts the wavelength of the laser light from the light source unit, and an elastic force are used. Wavelength conversion based on the measurement result of the fixed part that fixes the wavelength conversion element to the substrate, the temperature measurement part that is provided between the wavelength conversion element and the fixed part, and that measures the temperature of the wavelength conversion element It is possible to provide a light source device including a temperature adjusting unit that adjusts the temperature of the element.

  The fixing unit fixes the wavelength conversion element at a specific position with respect to the position of the substrate. The light source device of the present invention performs feedback control of the temperature adjustment unit based on the measurement result by the temperature measurement unit. By using the fixing part, the temperature measuring part is brought into contact with the wavelength conversion element by using the elastic force of the fixing part. By sufficiently bringing the temperature measurement unit into contact with the wavelength conversion element, the temperature of the wavelength conversion element can be accurately measured. By controlling the temperature adjustment unit based on the accurately measured temperature of the wavelength conversion element, the temperature change of the wavelength conversion element can be reduced. In addition, the influence on the temperature change due to external factors can be reduced. Thereby, the temperature change of a wavelength conversion element can be reduced, and the light source device which can supply the laser beam of the stable light quantity with high efficiency can be obtained.

  Moreover, as a preferable aspect of the present invention, it is desirable that the fixing portion includes a leaf spring portion that fixes the wavelength conversion element to the substrate using a spring force. As a result, simple and inexpensive manufacturing is possible, and the temperature measurement unit can be sufficiently brought into contact with the wavelength conversion element.

  Moreover, as a preferable aspect of the present invention, the wavelength conversion element includes a first surface provided on the substrate side and a second surface provided on the side opposite to the first surface, and the leaf spring portion is It is desirable to apply a spring force at the center of the second surface. Thereby, heat can be actively dissipated in the central portion of the wavelength conversion element where heat tends to concentrate, and the temperature of the wavelength conversion element can be made uniform.

  Moreover, as a preferable aspect of the present invention, it is desirable that the temperature adjustment unit includes a heat supply unit that supplies heat and a control unit that controls the heat supply unit based on a measurement result by the temperature measurement unit. Thereby, the temperature of a wavelength conversion element can be adjusted based on the measurement result by a temperature measurement part.

  Moreover, as a preferable aspect of the present invention, a heat diffusion unit is provided between the heat supply unit and the wavelength conversion element, and diffuses heat from the heat supply unit. It is desirable to fix. By using the thermal diffusion unit, the heat from the heat supply unit can be made uniform and propagated to the wavelength conversion element.

  Moreover, as a preferable aspect of the present invention, it is desirable that the temperature measurement unit is bonded to the fixed unit. Thereby, the temperature measurement unit can be fixed at a predetermined position, and the temperature measurement unit can be brought into direct contact with the wavelength conversion element without using an adhesive or the like.

  Moreover, as a preferable aspect of the present invention, it is desirable to have a wiring part connected to the temperature measurement part, and the wiring part is provided on the fixed part. Thereby, temperature measurement by a temperature measurement part can be performed.

  Moreover, as a preferable aspect of the present invention, it is desirable to have an insulating layer provided between the wiring portion and the fixed portion. Thereby, a wiring part and a fixing | fixed part can be insulated.

  Furthermore, according to the present invention, it is possible to provide a projector including the light source device described above and a spatial light modulation device that modulates light from the light source device in accordance with an image signal. By using the above light source device, it is possible to reduce the temperature change of the wavelength conversion element, and to supply a laser beam with a high amount of light with high efficiency. Thereby, a projector capable of stably displaying a bright image with high efficiency can be obtained.

  Embodiments of the present invention will be described below in detail with reference to the drawings.

  FIG. 1 shows a schematic configuration of a light source device 10 according to Embodiment 1 of the present invention. The light source device 10 includes a semiconductor laser 11. The semiconductor laser 11 is an edge-emitting laser, and is a light source unit that supplies laser light. The SHG element 12 is a wavelength conversion element that converts the wavelength of the laser light from the semiconductor laser 11. The SHG element 12 converts the laser beam from the semiconductor laser 11 into a laser beam having a half wavelength and emits it. For example, when 1064 nm laser light is incident on the SHG element 12 from the semiconductor laser 11, the SHG element 12 emits 532 nm laser light. As the SHG element 12, for example, a nonlinear optical crystal can be used.

  A thermal diffusion plate 14 is laminated on the support column 15. The thermal diffusion plate 14 is a thermal diffusion unit that diffuses heat from a heater, which will be described later, substantially uniformly. The SHG element 12 is provided on the thermal diffusion plate 14. By adopting a configuration in which the element that is in thermal contact with the SHG element 12 is substantially only the thermal diffusion plate 14, the SHG element 12 receives almost only the movement of heat from the thermal diffusion plate 14. By diffusing the heat substantially uniformly by the heat diffusing plate 14, the uniformed heat can be supplied to the SHG element 12. By enabling the uniform heat to be supplied to the SHG element 12, the temperature of the entire SHG element 12 can be made uniform. The thermal diffusion plate 14 can be formed using a member having high thermal conductivity, for example, copper. The semiconductor laser 11 and the support column 15 are provided on a common substrate 16. The substrate 16 is fixed to a package (not shown).

  FIG. 2 shows the SHG element 12 and each part around it. The SHG element 12 is covered with a leaf spring portion 13. The leaf spring portion 13 is a fixing portion that fixes the SHG element 12 to the heat diffusion plate 14 using a spring force that is an elastic force. By fixing the thermal diffusion plate 14 to the support column 15, the SHG element 12 is fixed to the substrate 16 (see FIG. 1). In this manner, the leaf spring portion 13 fixes the SHG element 12 at a specific position with respect to the position of the substrate 16. The leaf spring portion 13 can be formed by pressing a member having spring properties and high resistance to heat, such as phosphor bronze. The leaf spring 13 may be formed using, for example, stainless steel in addition to using phosphor bronze.

  FIG. 3 shows a perspective configuration of the SHG element 12. The SHG element 12 has a rectangular parallelepiped shape having a first surface 21 and a second surface 22 having a substantially rectangular shape. The first surface 21 is provided on the support column 15 (see FIG. 1) side and is in contact with the heat diffusion plate 14. The second surface 22 is provided on the side opposite to the first surface 21. The incident surface 23 allows light from the semiconductor laser 11 (see FIG. 1) to enter. The emission surface 24 emits laser light that has passed through the SHG element 12. The two side surfaces 25, 26 are surfaces other than the first surface 21, the second surface 22, the incident surface 23, and the exit surface 24, all of which are the first surface 21, the second surface 22, the entrance surface 23, and the exit surface. 24 is substantially orthogonal. The side surfaces 25 and 26 face each other.

  The z direction shown in the figure is a direction in which laser light travels. The x direction is a direction perpendicular to the z direction and is a horizontal direction. The y direction is a direction perpendicular to the z direction and is a vertical direction. In order to accurately transmit the laser beam to the SHG element 12, it is necessary to accurately align at least the positions in the x and y directions and the rotation around the y axis. The alignment of the SHG element 12 can be sufficiently performed with normal machining accuracy. In particular, the position of the SHG element 12 in the y direction can be accurately adjusted according to the thickness of the thermal diffusion plate 14 and the support column 15. In addition, the alignment may be performed with respect to the position in the z direction, the rotation about the x axis, and the rotation about the z axis.

  FIG. 4 shows a planar configuration of the support column 15. A heater 31 is embedded in the center of the surface of the support column 15 on the heat diffusion plate 14 side. The heater 31 is a heat supply unit that supplies heat. The heater 31 only needs to be able to supply heat to the SHG element 12 via the thermal diffusion plate 14, and may be disposed at a position other than the position described in the present embodiment.

  FIG. 5 shows a cross-sectional configuration of the SHG element 12 and each of its surrounding parts. The leaf spring 13 has a recess 19 provided corresponding to the center of the second surface 22 of the SHG element 12. A thermistor 40 is provided between the second surface 22 of the SHG element 12 and the concave portion 19 of the leaf spring portion 13. The thermistor 40 is a temperature measurement unit that measures the temperature of the SHG element 12. The leaf spring portion 13 applies a spring force to the central portion of the second surface 22 via the thermistor 40 in the recess 19. The thermistor 40 is pressed against the second surface 22 of the SHG element 12 by applying a spring force by the recess 19. The SHG element 12 is pressed against the heat diffusing plate 14 by applying a spring force by the recess 19.

  By using the leaf spring portion 13, the thermistor 40 can be sufficiently brought into contact with the SHG element 12. Moreover, the play of the SHG element 12 in the direction perpendicular to the first surface 21 and the second surface 22 (y direction shown in FIG. 3) can be prevented. By applying a spring force to the central portion of the second surface 22, it is possible to prevent the SHG element 12 from being inclined in any direction (rotation about the x axis and rotation about the z axis shown in FIG. 3).

  The leaf spring portion 13 has recesses 20 and 30 provided corresponding to the side surfaces 25 and 26 of the SHG element 12. The leaf spring portion 13 applies a spring force to the side surfaces 25 and 26 in the recesses 20 and 30. Since the spring forces applied to the side surfaces 25 and 26 are opposed to each other, rattling in the direction perpendicular to the side surfaces 25 and 26 (the x direction shown in FIG. 3) can be prevented. The SHG element 12 is fixed vertically and horizontally by the concave portion 19 on the second surface 22 side and the concave portions 20 and 30 on the side surfaces 25 and 26 side. A peripheral portion 32 surrounding the periphery of the SHG element 12 in the leaf spring portion 13 is fixed to the heat diffusing plate 14. For example, welding can be used for fixing the peripheral portion 32 and the heat diffusing plate 14. Welding is performed after performing the above-described alignment with respect to the SHG element 12.

  FIG. 6 shows an AA section of the configuration shown in FIG. The leaf spring portion 13 includes an incident side fitting portion 33 provided on the incident surface 23 side of the SHG element 12 and an emission side fitting portion 34 provided on the emission surface 24 side of the SHG element 12. The incident side fitting portion 33 is a fitting portion for fitting the SHG element 12 in a region other than the region L where the laser beam is incident on the incident surface 23. The emission side fitting portion 34 is a fitting portion for fitting the SHG element 12 in a region other than the region L where the laser beam is emitted on the emission surface 24. Thereby, the play of the SHG element 12 in the traveling direction of the laser light (z direction shown in FIG. 3) can be prevented without blocking the laser light.

  FIG. 7 shows a BB cross section of the configuration shown in FIG. Each of the incident side fitting portion 33 and the emission side fitting portion 34 has a shape that gradually expands toward the end portion 35 on the support column 15 side. By making the interval between the end portion 35 of the incident side fitting portion 33 and the end portion 35 of the emission side fitting portion 34 larger than the width of the SHG element 12, the SHG element 12 can be easily inserted into the leaf spring portion 13. It becomes possible. Of the incident side fitting portion 33 and the emission side fitting portion 34, the side opposite to the end portion 35 is formed to be substantially the same as or slightly smaller than the width of the SHG element 12. Thereby, the SHG element 12 can be easily fixed to the leaf spring part 13.

  FIG. 8 shows the thermistor 40 and its surrounding parts. The thermistor 40 is bonded to the leaf spring portion 13 by an adhesive layer 41. The adhesive layer 41 is configured using, for example, a thermosetting resin. Thereby, the thermistor 40 can be fixed at a predetermined position, and the thermistor 40 can be brought into contact with the SHG element 12. The thermistor 40 is connected to a flexible cable 42 provided on the leaf spring portion 13. The flexible cable 42 is a wiring portion connected to the thermistor 40. The thermistor 40 measures temperature by supplying power via the flexible cable 42. As the wiring portion, a lead wire or the like can be used in addition to the flexible cable 42.

  FIG. 9 shows a block configuration for adjusting the temperature of the SHG element 12 based on the measurement result by the thermistor 40. The control unit 43 controls the heater driving unit 44 according to the output of the thermistor 40. The heater driving unit 44 drives the heater 31 according to control by the control unit 43. Thus, the control unit 43 performs feedback control of the heater 31 based on the measurement result by the thermistor 40. The heater 31 and the control unit 43 constitute a temperature adjustment unit that adjusts the temperature of the SHG element 12 based on the measurement result by the thermistor 40.

  The temperature of the SHG element 12 can be accurately measured by sufficiently bringing the thermistor 40 into contact with the SHG element 12 using the spring force of the leaf spring portion 13. By controlling the heater 31 based on the accurately measured temperature of the SHG element 12, the temperature change of the SHG element 12 can be reduced. In addition, the influence on the temperature change due to external factors can be reduced. As a result, the temperature change of the wavelength conversion element can be reduced, and a laser beam with a stable light quantity can be supplied with high efficiency.

  Note that heat conductive grease or a heat conductive adhesive may be interposed between the thermistor 40 and the SHG element 12. Thereby, the thermistor 40 can be fixed to the SHG element 12 and accurate temperature measurement can be performed by the thermistor 40. Further, as shown in FIG. 10, an insulating layer 46 may be provided. The insulating layer 46 is provided between the wiring 45 and the leaf spring portion 13. The insulating layer 46 insulates the wiring 45 from the leaf spring portion 13. The insulating layer 46 can be formed using, for example, an insulating resin such as polyimide. The wiring 45 is a wiring portion connected to the thermistor 40 and is mounted on the insulating layer 46. The wiring 45 can be formed by patterning a metal film, for example. The thermistor 40 and the wiring 45 are connected by, for example, soldering.

  In addition to using welding for fixing the peripheral portion 32 of the leaf spring portion 13 and the heat diffusion plate 14, a screw 36 may be used as shown in FIG. In addition to fixing the peripheral portion 32 and the heat diffusion plate 14, the screw 36 may fix the peripheral portion 32, the heat diffusion plate 14, and the support column 15. The fixing of the peripheral portion 32 of the leaf spring portion 13 and the heat diffusing plate 14 is not limited to the case where the screw 36 is used, and other mechanical structures capable of fixing the peripheral portion 32 and the heat diffusing plate 14 may be used. .

  The configuration of the light source device of the present invention may be changed as appropriate. For example, as in a light source device 50 shown in FIG. 12, a semiconductor laser 51 that is a surface emitting laser may be used. The semiconductor laser 51 and the support column 15 are fixed on the substrate 52. The SHG element 12 is fixed to the substrate 52 by the leaf spring portion 13. As the light source unit used in the light source device, in addition to the semiconductor lasers 11 and 51, a solid laser, a liquid laser, a gas laser, or the like may be used.

A light source device 60 shown in FIG. 13 is a semiconductor laser pumped solid state (DPSS) laser oscillator. The light source device 60 has a resonator structure using resonant mirrors 62 and 64. The excitation laser 61 supplies laser light having a wavelength of 808 nm, for example. The laser light from the excitation laser 61 passes through the resonance mirror 62 and then enters the laser crystal 63. As the laser crystal 63, for example, a Nd: YVO ₄ crystal or a Nd: YAG (Y ₃ Al ₅ O ₁₂ ) crystal can be used.

  The laser crystal 63 oscillates when excited, and supplies laser light having a wavelength of about 1060 nm, for example. Laser light from the laser crystal 63 is converted into laser light having a half wavelength by the SHG element 12. For example, a 1064 nm laser beam is converted into a 532 nm laser beam. The laser beam converted to a desired wavelength passes through the resonance mirror 64. Laser light having a wavelength other than the desired wavelength is reflected by the resonance mirror 64. The laser light converted to a desired wavelength between the two resonance mirrors 62 and 64 passes through the resonance mirror 64. In this way, laser light with a desired wavelength can be emitted efficiently.

  FIG. 14 shows a schematic configuration of a projector 70 according to Embodiment 2 of the present invention. The projector 70 is a front projection type projector that views light by supplying light to the screen 88 and observing light reflected by the screen 88. A duplicate description with the first embodiment is omitted. The projector 70 includes a red (R) light source device 80R, a green (G) light source device 80G, and a blue (B) light source device 80B. Each of the color light source devices 80R, 80G, and 80B has the same configuration as the light source device 10 (see FIG. 1) of the first embodiment. The projector 70 displays an image using light from each color light source device 80R, 80G, 80B.

  The R light source device 80R is a light source device that supplies R light. The diffractive optical element 81 shapes and enlarges the illumination area by diffracting the laser light. The diffractive optical element 81 also makes the light amount distribution of the laser light uniform. As the diffractive optical element 81, for example, a computer generated hologram (CGH) can be used. The field lens 82 collimates the laser light from the diffractive optical element 81 and enters the R light spatial light modulator 83R. The spatial light modulator 83R for R light is a spatial light modulator that modulates R light according to an image signal, and is a transmissive liquid crystal display device. The R light modulated by the R light spatial light modulator 83R is incident on a cross dichroic prism 84 which is a color synthesis optical system.

  The G light source device 80G is a light source device that supplies G light. The laser light that has passed through the diffractive optical element 81 and the field lens 82 enters the G light spatial light modulator 83G. The G light spatial light modulator 83G is a spatial light modulator that modulates G light according to an image signal, and is a transmissive liquid crystal display device. The G light modulated by the G light spatial light modulator 83G enters the cross dichroic prism 84 from a side different from the R light.

  The light source device for B light 80B is a light source device that supplies B light. The laser light that has passed through the diffractive optical element 81 and the field lens 82 enters the spatial light modulator 83B for B light. The spatial light modulator for B light 83B is a spatial light modulator that modulates B light according to an image signal, and is a transmissive liquid crystal display device. The B light modulated by the B light spatial light modulator 83B enters the cross dichroic prism 84 from a side different from the R light and the G light. As the transmissive liquid crystal display device, for example, a high temperature polysilicon TFT liquid crystal panel (HTPS) can be used.

  The cross dichroic prism 84 has two dichroic films 85 and 86 disposed substantially orthogonal to each other. The first dichroic film 85 reflects R light and transmits G light and B light. The second dichroic film 86 reflects B light and transmits R light and G light. The cross dichroic prism 84 combines the R light, the G light, and the B light incident from different directions and emits them in the direction of the projection lens 87. The projection lens 87 projects the light combined by the cross dichroic prism 84 in the direction of the screen 88.

  By using each color light source device 80R, 80G, 80B having the same configuration as the light source device 10 described above, it is possible to reduce the temperature change of the wavelength conversion element, and to supply a laser beam with a high efficiency and a stable light amount. Thereby, there is an effect that a bright image can be stably displayed with high efficiency. The projector 70 is not limited to the case where a transmissive liquid crystal display device is used as the spatial light modulation device. As the spatial light modulator, a reflective liquid crystal display (Liquid Crystal On Silicon; LCOS), DMD (Digital Micromirror Device), GLV (Grating Light Valve), or the like may be used.

  The projector 70 is not limited to a configuration including a spatial light modulator for each color light. The projector 70 may be configured to modulate two or three or more color lights with one spatial light modulator. The projector may be a so-called rear projector that supplies light to one surface of the screen and observes an image by observing light emitted from the other surface of the screen. Furthermore, the light source device of the present invention is not limited to being applied to a projector. For example, the present invention may be applied to an exposure apparatus that performs exposure using laser light, a monitor apparatus that monitors an image illuminated by laser light, and the like.

  As described above, the light source device according to the present invention is suitable for use in a projector.

The figure which shows schematic structure of the light source device which concerns on Example 1 of this invention. The figure which shows each part of a SHG element and its periphery. The figure which shows the perspective structure of a SHG element. The figure which shows the planar structure of a support | pillar. The figure which shows the cross-sectional structure of each part of a SHG element and its periphery. The figure which shows the AA cross section of the structure shown in FIG. The figure which shows the BB cross section of the structure shown in FIG. The figure which shows each part of the thermistor and its periphery. The figure which shows the block structure for adjusting the temperature of a SHG element. The figure which shows the structure which provides an insulating layer. The figure explaining the structure which fixes a leaf | plate spring part using a screw. The figure explaining the structure using a surface emitting laser. The figure explaining a DPSS laser oscillator. FIG. 5 is a diagram illustrating a schematic configuration of a projector according to a second embodiment of the invention.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 10 Light source device, 11 Semiconductor laser, 12 SHG element, 13 Leaf spring part, 14 Thermal diffusion plate, 15 Support | pillar, 16 Substrate, 19 Recessed part, 20, 30 Recessed part, 21 1st surface, 22 2nd surface, 23 Incident surface, 24 exit surface, 25, 26 side surface, 31 heater, 32 peripheral portion, 33 entrance side fitting portion, 34 exit side fitting portion, 35 end portion, 36 screw, 40 thermistor, 41 adhesive layer, 42 flexible cable, 43 control , 44 heater driving unit, 45 wiring, 46 insulating layer, 50 light source device, 51 semiconductor laser, 52 substrate, 60 light source device, 61 excitation laser, 62, 64 resonant mirror, 63 laser crystal, 70 projector, 80R R light Light source device, 80 G light source device, 80 B light source device, 81 diffractive optical element, 82 field lens, 83 R spatial light modulator, 83G G-light spatial light modulator, 83B B-light spatial light modulator, 84 a cross dichroic prism, 85 a first dichroic film, 86 second dichroic film, 87 projection lens, 88 screen

Claims (9)

A light source unit for supplying laser light;
A wavelength conversion element that converts the wavelength of the laser light from the light source unit;
A fixing portion for fixing the wavelength conversion element to the substrate using elastic force;
A temperature measuring unit that is provided between the wavelength converting element and the fixing unit and measures the temperature of the wavelength converting element;
And a temperature adjusting unit that adjusts the temperature of the wavelength conversion element based on a measurement result by the temperature measuring unit.   The light source device according to claim 1, wherein the fixing portion includes a leaf spring portion that fixes the wavelength conversion element to the substrate using a spring force. The wavelength conversion element includes a first surface provided on the substrate side, and a second surface provided on the side opposite to the first surface,
The light source device according to claim 2, wherein the leaf spring portion applies a spring force at a central portion of the second surface.   The said temperature control part is provided with the heat supply part which supplies heat, and the control part which controls the said heat supply part based on the measurement result by the said temperature measurement part, The any one of Claims 1-3 characterized by the above-mentioned. The light source device according to claim 1. A thermal diffusion unit that is provided between the heat supply unit and the wavelength conversion element and diffuses heat from the heat supply unit;
The light source device according to claim 4, wherein the fixing unit fixes the wavelength conversion element to the thermal diffusion unit.   The light source device according to claim 1, wherein the temperature measurement unit is bonded to the fixing unit. It has a wiring part connected to the temperature measuring part,
The light source device according to claim 1, wherein the wiring portion is provided on the fixed portion.   The light source device according to claim 7, further comprising an insulating layer provided between the wiring portion and the fixing portion. The light source device according to any one of claims 1 to 8,
And a spatial light modulator that modulates light from the light source device in accordance with an image signal.

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