Projection type display device

Abstract

To provide a projection display device that is compact. [Solution] The device comprises a cross separation element 9 having a first color separation element 11 and a second color separation element 12 arranged crosswise to each other, wherein the long-wavelength blue light from the light emitted from the light source device 1 is reflected by the first color separation element 11 and emitted in a first direction parallel to a first axis within a predetermined plane, the short-wavelength red light from the light emitted from the light source device 1 is reflected by the second color separation element 12 and emitted in the opposite direction to the blue light in the first direction, and the green light of the light emitted from the light source device 1, which has a wavelength between the blue light and the red light, is transmitted through the first color separation element 11 and the second color separation element 12 and emitted in a second direction parallel to a second axis perpendicular to the first axis within the predetermined plane, and a relay optical system 20 arranged in the optical path of the blue light between the cross separation element 9 and the first reflective liquid crystal panel 31 and forms an erect image, and the optical path lengths of the red light and green light from the cross separation element 9 to the second reflective liquid crystal panel 32 and the third reflective liquid crystal panel 33 are the same.

Description

[Technical Field]

[0001] The present invention relates to a projection display device. [Background technology]

[0002] Generally, a projection display device is known that includes an illumination optical system that illuminates a plurality of light modulation elements with different colored lights, a combining optical system that combines the colored lights modulated by the light modulation elements to generate combined light, and a projection optical system that projects the combined light generated by the combining optical system (see, for example, Patent Document 1). In this type of projection display device, the illumination optical system has a plurality of optical components such as mirrors, lenses, and color separation elements. Light emitted from a light source is separated into a plurality of colored lights by passing through the optical components of the illumination optical system, and the separated light is irradiated onto the light modulation elements. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Laid-Open No. 2008-158274 Summary of the Invention [Problem to be solved by the invention]

[0004] In the conventional configuration, the light emitted from the light source is sequentially separated into multiple color lights by passing through multiple color separation elements, which means that the device becomes larger, leaving room for improvement.

[0005] An object of an aspect of the present invention is to provide a projection display device that is miniaturized. [Means for solving the problem]

[0006] A projection display device according to the present invention has a first color separation element and a second color separation element arranged to intersect with each other, and includes a cross separation element that reflects blue light having a long wavelength from light emitted from a light source device by the first color separation element and emits it in a first direction parallel to a first axis in a predetermined plane, reflects red light having a short wavelength from light emitted from the light source device by the second color separation element and emits it in a direction opposite to the blue light in the first direction, and transmits green light of a wavelength between the blue light and the red light from the light emitted from the light source device through the first color separation element and the second color separation element and emits it in a second direction parallel to a second axis perpendicular to the first axis in the predetermined plane, a first reflecting member that reflects the blue light reflected by the first color separation element in a third direction parallel to a third axis perpendicular to the predetermined plane, a second reflecting member that reflects the red light reflected by the second color separation element in the third direction, a third reflecting member that reflects the green light transmitted through the first color separation element and the second color separation element in the third direction, and a first reflecting section. a first reflective liquid crystal panel having a first incident surface onto which blue light reflected by the second reflecting member is incident and optically modulating the blue light based on image data; a second reflective liquid crystal panel having a second incident surface onto which red light reflected by the second reflecting member is incident and optically modulating the red light based on image data; a third reflective liquid crystal panel having a third incident surface onto which green light reflected by the third reflecting member is incident and optically modulating the green light based on image data; a combining optical system that combines the blue light optically modulated by the first reflective liquid crystal panel, the red light optically modulated by the second reflective liquid crystal panel, and the green light optically modulated by the third reflective liquid crystal panel to generate combined light; a projection optical system that projects the combined light generated by the combining optical system; and a relay optical system that is arranged in the optical path of the blue light between the cross separation element and the first reflective liquid crystal panel and forms an erect image, wherein the optical path lengths of the red light and the green light from the cross separation element to the second reflective liquid crystal panel and the third reflective liquid crystal panel are the same. [Effects of the Invention]

[0007] According to the present invention, the device comprises a cross-separation element having a first color separation element and a second color separation element arranged to intersect each other, and a relay optical system arranged in the optical path of blue light between the cross-separation element and a first reflective liquid crystal panel to form an erect image. Since the optical path lengths of red light and green light from the cross-separation element to the second reflective liquid crystal panel and the third reflective liquid crystal panel are made the same, the light emitted from the light source device can be separated into blue light, red light, and green light by the cross-separation element, and the blue light, red light, and green light can be imaged by the first reflective liquid crystal panel, the second reflective liquid crystal panel, and the third reflective liquid crystal panel, respectively, thereby enabling miniaturization of the device configuration of the projection display device. [Brief explanation of the drawings]

[0008] [Figure 1] FIG. 1 is a plan view schematically showing an example of a projection display device according to this embodiment. [Figure 2] FIG. 2 is a perspective view schematically illustrating an example of a projection display device according to this embodiment. [Figure 3] FIG. 3 is a perspective view for explaining the operation of the projection display device according to this embodiment. [Figure 4] FIG. 4 is a plan view schematically showing a part of a cooling mechanism that cools the projection display device according to this embodiment. [Figure 5] FIG. 5 is a cross-sectional view taken along line VV of FIG. [Figure 6] FIG. 6 is a perspective view schematically illustrating an example of a sealed box according to this embodiment. DETAILED DESCRIPTION OF THE INVENTION

[0009] Although the present invention will be described with reference to the drawings, the present invention is not limited thereto. The components of the embodiments described below can be combined as appropriate. In addition, some components may not be used.

[0010] In the following description, an XYZ Cartesian coordinate system is set, and the positional relationship of each part will be described with reference to this XYZ Cartesian coordinate system. The direction parallel to the X axis, which is the first axis within a predetermined plane, is defined as the X axis direction. The direction parallel to the Y axis, which is the second axis orthogonal to the first axis within the predetermined plane, is defined as the Y axis direction. The direction parallel to the Z axis, which is the third axis orthogonal to the first and second axes, is defined as the Z axis direction. The third axis is orthogonal to the predetermined plane. Furthermore, one direction in the X axis direction is defined as the +X direction, and the opposite direction of the +X direction (also referred to as the reverse direction) is defined as the -X direction. One direction in the Y axis direction is defined as the +Y direction, and the opposite direction of the +Y direction is defined as the -Y direction. One direction in the Z axis direction is defined as the +Z direction, and the opposite direction of the +Z direction is defined as the -Z direction. In this embodiment, the predetermined plane is parallel to a horizontal plane, and the Z axis direction is the vertical direction. In the following description, the predetermined plane will be referred to as the XY plane as appropriate.

[0011] FIG. 1 is a plan view schematically illustrating an example of a projection display device 100 according to this embodiment. FIG. 2 is a perspective view schematically illustrating an example of the projection display device 100 according to this embodiment. As shown in FIGS. 1 and 2, the projection display device 100 includes a light source device 1 that emits light (light source light), a cross separation element 9 in which two separation elements are arranged crossing each other, and an illumination optical system 10 that separates the light emitted from the light source device 1 by color to generate a first color light (blue light) Lb, a second color light (red light) Lr, and a third color light (green light) Lg, and an illumination optical system 10 that is arranged on the optical paths of the first color light Lb, the second color light Lr, and the third color light Lg generated by the illumination optical system 10 and that outputs the first color light Lb, the second color light Lr, and the third color light Lg based on image data. The optical system includes a first reflective liquid crystal panel 31, a second reflective liquid crystal panel 32, and a third reflective liquid crystal panel 33 that optically modulate the first color light Lb, the second color light Lr, and the third color light Lg, respectively; a combining optical system 40 that combines the first color light Lb, the second color light Lr, and the third color light Lg that have been optically modulated by the first reflective liquid crystal panel 31, the second reflective liquid crystal panel 32, and the third reflective liquid crystal panel 33 to generate combined light; and a projection optical system 50 that projects the combined light generated by the combining optical system 40.

[0012] The light source device 1 generates white light, which is light source light. In this embodiment, the light source device 1 includes a solid-state light source 2 that emits excitation light, a phosphor 3 that generates fluorescence when irradiated with the excitation light, a half mirror (dichroic mirror) 4 that guides the excitation light emitted from the solid-state light source 2 to the phosphor 3, and a focusing optical system (condensing lens) 5 that focuses the excitation light irradiated on the phosphor 3. The solid-state light source 2 includes a laser diode (LD). The solid-state light source 2 emits blue laser light of a specific wavelength as excitation light. The excitation light emitted from the solid-state light source 2 is irradiated onto the phosphor 3 via the half mirror 4 and the focusing optical system 5. When irradiated with the excitation light, the phosphor 3 generates yellow fluorescence with a wavelength different from that of the excitation light (blue laser light). White light is generated based on the excitation light and the fluorescence. The white light generated by the light source device 1 enters an illumination optical system 10.

[0013] The illumination optical system 10 separates the light emitted from the light source device 1 into a plurality of color lights Lb, Lr, and Lg. The illumination optical system 10 causes the first color light Lb to be incident on a first reflective liquid crystal panel 31, the second color light Lr to be incident on a second reflective liquid crystal panel 32, and the third color light Lg to be incident on a third reflective liquid crystal panel 33. The illumination optical system 10 comprises an integrator optical system 6 into which light from the light source device 1 is incident, a cross separation element 9 that separates the light emitted from the integrator optical system 6 into first color light Lb, second color light Lr, and third color light Lg, a first reflecting member 13 that reflects the first color light Lb separated by the cross separation element 9 in the +Z direction, a second reflecting member 14 that reflects the second color light Lr separated by the cross separation element 9 in the +Z direction, a third reflecting member 15 that reflects the third color light Lg separated by the cross separation element 9 in the +Z direction, and a relay optical system 20 that is arranged in the optical path of the first color light Lb and forms an erect image.

[0014] The integrator optical system 6 uniforms the illuminance of the light emitted from the light source device 1. The integrator optical system 6 includes a first lens array (fly's eye lens) 6A, a second lens array (fly's eye lens) 6B, a polarization conversion element 7, and a condenser lens (first optical component) 8. The optical axis of the integrator optical system 6 is parallel to the Y axis. The light emitted from the integrator optical system 6 travels in the +Y direction.

[0015] The first lens array 6A has a plurality of microlenses arranged in a matrix in the XZ plane. The second lens array 6B has a plurality of microlenses arranged in a matrix in the XZ plane. There is a one-to-one correspondence between the plurality of microlenses of the first lens array 6A and the plurality of microlenses of the second lens array 6B. The polarization conversion element 7 has a plurality of polarization conversion units. The polarization conversion units include a polarization separation film, a reflecting mirror, and a phase plate. There is a one-to-one correspondence between the plurality of microlenses of the second lens array 6B and the plurality of polarization conversion units of the polarization conversion element 7.

[0016] Light emitted from the light source device 1 and entering the integrator optical system 6 is incident on each of the multiple microlenses of the first lens array 6A. Depending on the position of the microlens, a portion of the light incident on the entrance surface of the integrator optical system 6 is incident on each of the multiple microlenses of the first lens array 6A. Therefore, each microlens receives different light. Each microlens of the first lens array 6A focuses the light emitted from the light source device 1 onto each microlens of the second lens array 6B corresponding to the corresponding microlens of the first lens array 6A. A secondary light source image is formed on each of the multiple microlenses of the second lens array 6B. The second lens array 6B constitutes the optical pupil of the first lens array 6A.

[0017] Light from the secondary light source images formed on each microlens of the second lens array 6B is incident on each polarization conversion unit of the polarization conversion element 7 corresponding to the microlens of the second lens array 6B. The light incident on the polarization conversion unit is separated into light of a first polarization state and light of a second polarization state by a polarization separation film. The light of the second polarization state separated by the polarization separation film is reflected by a reflecting mirror and then passes through a phase plate, where it is converted into light of the first polarization state. In other words, the light emitted from the light source device 1 is converted into light of the first polarization state by passing through the polarization conversion element 7.

[0018] The light emitted from each of the multiple polarization conversion units is incident on the condenser lens 8. The condenser lens 8 superimposes the light emitted from each of the multiple polarization conversion units into a single light beam. This homogenizes the illuminance distribution on each of the first reflective liquid crystal panel 31, the second reflective liquid crystal panel 32, and the third reflective liquid crystal panel 33. The condenser lens 8 also functions as a first optical component that adjusts the direction of bias in the light intensity distribution of the second color light Lr, which is red light, and the third color light Lg, which is green light, separated by the cross separation element 9, by adjusting the light emitted from the light source device 1. The integrator optical system 6 may include a rod integrator.

[0019] The cross separation element 9 has a first color separation element 11 and a second color separation element 12, which are integrally formed and cross each other in an X-shape when viewed from the Z direction. The cross separation element 9 is disposed on the -Y side of the integrator optical system 6. The first color separation element 11 and the second color separation element 12 each include a dichroic mirror. The first color separation element 11 reflects and separates the first color light Lb from the light emitted from the light source device 1 and transmitted through the integrator optical system 6. The second color separation element 12 reflects and separates the second color light Lr from the light transmitted through the integrator optical system 6. In this embodiment, the first color separation element 11 reflects the first color light Lb and transmits the second color light Lr and the third color light Lg. The second color separation element 12 reflects the second color light Lr and transmits the first color light Lb and the third color light Lg. Therefore, the cross separation element 9 separates the white light from the light source device 1 into blue light, which is the first color light Lb, and light of a different wavelength from the blue light, using the first color separation element 11, and separates the white light from the light source device 1 into red light, which is the second color light Lr, and light of a different wavelength from the red light, using the second color separation element 12. The first color light Lb, which is blue light, is reflected by the first color separation element 11 and travels in the -X direction. The second color light Lr, which is red light, is reflected by the second color separation element 12 and travels in the +X direction. The remaining third color light Lg, which is green light, is transmitted through the first color separation element 11 and the second color separation element 12 and travels in the +Y direction.

[0020] The first reflecting member 13 reflects the first color light Lb from the first color separation element 11 in the +Z direction. In this embodiment, the illumination optical system 10 has a fourth reflecting member 16 and a fifth reflecting member 17 disposed between the first color separation element 11 and the first reflecting member 13. The fourth reflecting member 16 is disposed on the -X side of the first color separation element 11, and the fifth reflecting member 17 is disposed on the -Y side of the fourth reflecting member 16. The fourth reflecting member 16 reflects the first color light Lb from the first color separation element 11 in the -Y direction, and the fifth reflecting member 17 reflects the first color light Lb from the fourth reflecting member 16 in the +X direction. The first color light Lb traveling in the -X direction from the first color separation element 11 is reflected by the reflecting surface 16A of the fourth reflecting member 16 and travels in the -Y direction, and then reflected by the reflecting surface 17A of the fifth reflecting member 17 and travels in the +X direction. The first reflecting member 13 is disposed on the +X side of the fifth reflecting member 17. The first colored light Lb traveling in the +X direction from the fifth reflecting member 17 is reflected by the reflecting surface 13A of the first reflecting member 13 and travels in the +Z direction.

[0021] The second reflecting member 14 reflects the second color light Lr from the second color separation element 12 in the +Z direction. The second reflecting member 14 is disposed on the +X side of the second color separation element 12. The second color light Lr traveling in the +X direction from the second color separation element 12 is reflected by the reflecting surface 14A of the second reflecting member 14 and travels in the +Z direction.

[0022] Third reflecting member 15 reflects in the +Z direction third color light Lg that has passed through first color separation element 11 and second color separation element 12. Third reflecting member 15 is disposed on the -Y side of first color separation element 11 and second color separation element 12. Third color light Lg traveling in the +Y direction from first color separation element 11 and second color separation element 12 is reflected by reflecting surface 15A of third reflecting member 15 and travels in the +Z direction.

[0023] In this embodiment, reflecting surface 13A of first reflecting member 13 and reflecting surface 14A of second reflecting member 14 are parallel to each other. Reflecting surface 13A of first reflecting member 13 is parallel to the Y axis and is inclined in the +Z direction toward the -X direction. Similarly, reflecting surface 15A of third reflecting member 15 is parallel to the X axis and is inclined in the +Z direction toward the +Y direction.

[0024] In this embodiment, reflective surface 13A of first reflective member 13 and reflective surface 14A of second reflective member 14 are arranged in the same plane. The plane including reflective surface 13A of first reflective member 13 and reflective surface 14A of second reflective member 14 is perpendicular to the plane including reflective surface 15A of third reflective member 15.

[0025] The relay optical system 20 is disposed on the optical path of the first color light Lb between the first color separation element 11 and the first reflective liquid crystal panel 31. In this embodiment, the relay optical system 20 is disposed on the optical path of the first color light Lb between the first color separation element 11 and the first reflecting member 13. The relay optical system 20 forms an erect image of an object on the object plane side of the relay optical system 20 on the image plane side of the relay optical system 20.

[0026] The relay optical system 20 includes a first condenser lens 21 disposed between the fourth reflecting member 16 and the fifth reflecting member 17, and a second condenser lens 22 and a third condenser lens 23 disposed between the fifth reflecting member 17 and the first reflecting member 13. The first condenser lens 21, the second condenser lens 22, and the third condenser lens 23 are each a convex lens. The third condenser lens 23 is optically conjugate with the second lens array 6B. Because the third condenser lens 23 and the second lens array 6B are optically conjugate with each other and the second lens array 6B acts as a pupil of the first lens array 6A, an image of each microlens of the first lens array 6A is formed between the second lens array 6B and the third condenser lens 23. In this embodiment, a lens (e.g., the third condenser lens 23) included in the relay optical system 20 functions as a second optical component that adjusts the direction of bias in the light intensity distribution of the first colored light Lb, which is blue light separated by the cross separation element 9.

[0027] In this embodiment, the relay optical system 20 forms an erect image of an object on the image plane side of the relay optical system 20. For example, when an image X is formed on the object plane side of the relay optical system 20, the relay optical system 20 forms an inverted image of the image X between the first color separation element 11 and the first reflective liquid crystal panel 31, which is the image plane, and forms an erect image of the image X on the image plane side of the relay optical system 20. In this embodiment, the image X refers to each of the images of a portion of the light emitted from the light source device 1 and received by each of the multiple microlenses of the first lens array 6A.

[0028] The first reflective liquid crystal panel 31 is disposed in the optical path of the first color light Lb. The first reflective liquid crystal panel 31 is an optical modulation element that optically modulates the first color light Lb from the first reflecting member 13 based on image data. The first reflective liquid crystal panel 31 is disposed on the +Z side of the first reflecting member 13. The first color light Lb traveling in the +Z direction from the first reflecting member 13 is incident on the first reflective liquid crystal panel 31.

[0029] The first reflective liquid crystal panel 31 has a first incident surface 31A to which the first color light Lb from the first reflective member 13 is incident. The first reflective liquid crystal panel 31 reflects the first color light Lb from the first reflective member 13 in the -Z direction.

[0030] The second reflective liquid crystal panel 32 is disposed in the optical path of the second color light Lr. The second reflective liquid crystal panel 32 is an optical modulation element that optically modulates the second color light Lr from the second reflecting member 14 based on image data. The second reflective liquid crystal panel 32 is disposed on the +Z side of the second reflecting member 14. The second color light Lr traveling in the +Z direction from the second reflecting member 14 is incident on the second reflective liquid crystal panel 32.

[0031] The second reflective liquid crystal panel 32 has a second incident surface 32A to which the second color light Lr from the second reflective member 14 is incident. The second reflective liquid crystal panel 32 reflects the second color light Lr from the second reflective member 14 in the -Z direction.

[0032] The third reflective liquid crystal panel 33 is disposed in the optical path of the third color light Lg. The third reflective liquid crystal panel 33 is an optical modulation element that optically modulates the third color light Lg from the third reflecting member 15 based on image data. The third reflective liquid crystal panel 33 is disposed on the +Z side of the third reflecting member 15. The third color light Lg traveling in the +Z direction from the third reflecting member 15 is incident on the third reflective liquid crystal panel 33.

[0033] The third reflective liquid crystal panel 33 has a third incident surface 33A onto which the third color light Lg is incident from the third reflecting member 15. The third reflective liquid crystal panel 33 reflects the third color light Lg from the third reflecting member 15 in the −Z direction.

[0034] The first incident surface 31A of the first reflective liquid crystal panel 31 is parallel to the XY plane and faces the -Z direction. Similarly, the second incident surface 32A of the second reflective liquid crystal panel 32 and the third incident surface 33A of the third reflective liquid crystal panel 33 are parallel to the XY plane and face the -Z direction. In this embodiment, the first incident surface 31A of the first reflective liquid crystal panel 31, the second incident surface 32A of the second reflective liquid crystal panel 32, and the third incident surface 33A of the third reflective liquid crystal panel 33 are arranged in the same plane parallel to the XY plane.

[0035] A condenser lens 25, a first polarizer 61, and a second polarizer 62 are arranged in the optical path of the first color light Lb between the first reflecting member 13 and the first reflective liquid crystal panel 31. A condenser lens 26, a third polarizer 63, and a fourth polarizer 64 are arranged in the optical path of the second color light Lr between the second reflecting member 14 and the second reflective liquid crystal panel 32. A condenser lens 27, a fifth polarizer 65, and a sixth polarizer 66 are arranged in the optical path of the third color light Lg between the third reflecting member 15 and the third reflective liquid crystal panel 33.

[0036] The first polarizer 61 transmits the first color light Lb in the first polarization state reflected by the first reflecting member 13. The first color light Lb in the first polarization state transmitted through the first polarizer 61 is incident on the first reflective liquid crystal panel 31 via the second polarizer 62. The first reflective liquid crystal panel 31 optically modulates the first color light Lb from the first polarizer 61 based on image data. The second polarizer 62 is disposed in the optical path of the first color light Lb between the first polarizer 61 and the first reflective liquid crystal panel 31. The second polarizer 62 transmits the first color light Lb in the first polarization state from the first polarizer 61 and reflects the first color light Lb in the second polarization state from the first reflective liquid crystal panel 31 to the combining optical system 40.

[0037] The third polarizer 63 transmits the second color light Lr in the first polarization state reflected by the second reflecting member 14. The second color light Lr in the first polarization state transmitted through the third polarizer 63 is incident on the second reflective liquid crystal panel 32 via the fourth polarizer 64. The second reflective liquid crystal panel 32 optically modulates the second color light Lr from the third polarizer 63 based on image data. The fourth polarizer 64 is disposed in the optical path of the second color light Lr between the third polarizer 63 and the second reflective liquid crystal panel 32. The fourth polarizer 64 transmits the second color light Lr in the first polarization state from the third polarizer 63 and reflects the second color light Lr in the second polarization state from the second reflective liquid crystal panel 32 to the combining optical system 40.

[0038] The fifth polarizer 65 transmits the third color light Lg in the first polarization state reflected by the third reflecting member 15. The third color light Lg in the first polarization state transmitted by the fifth polarizer 65 is incident on the third reflective liquid crystal panel 33 via the sixth polarizer 66. The third reflective liquid crystal panel 33 optically modulates the third color light Lg from the fifth polarizer 65 based on image data. The sixth polarizer 66 is disposed in the optical path of the third color light Lg between the fifth polarizer 65 and the third reflective liquid crystal panel 33. The sixth polarizer 66 transmits the third color light Lg in the first polarization state from the fifth polarizer 65 and reflects the third color light Lg in the second polarization state from the third reflective liquid crystal panel 33 to the combining optical system 40.

[0039] A transmissive polarizer 67 is disposed in the optical path of the first color light Lb between the second polarizer 62 and the combining optical system 40. The transmissive polarizer 67 transmits the first color light Lb in the second polarization state out of the first color light Lb emitted from the second polarizer 62 to the combining optical system 40, and prevents the transmission of unnecessary first color light Lb in the first polarization state.

[0040] A transmissive polarizer 68 is disposed in the optical path of the second color light Lr between the fourth polarizer 64 and the combining optical system 40. The transmissive polarizer 68 transmits the second color light Lr in the second polarization state out of the second color light Lr emitted from the fourth polarizer 64 to the combining optical system 40, and prevents the transmission of unnecessary second color light Lr in the first polarization state.

[0041] A transmissive polarizer 69 is positioned in the optical path of the third-color light Lg between the sixth polarizer 66 and the composite optical system 40. The transmissive polarizer 69 transmits the third-color light Lg in the second polarization state from the third-color light Lg emitted from the sixth polarizer 66 to the composite optical system 40, and prevents the transmission of unwanted third-color light Lg in the first polarization state. The first polarization state is, for example, the P polarization state. The second polarization state is, for example, the S polarization state.

[0042] In this embodiment, the projection display device 100 has the same optical path length from the cross-separation element 9 to the second reflective liquid crystal panel 32 corresponding to red light, and the same optical path length from the cross-separation element 9 to the third reflective liquid crystal panel 33 corresponding to green light. The optical components placed in the respective optical paths for red and green light are also the same. Therefore, the red and green light separated by the cross-separation element 9 can be appropriately sent to the second reflective liquid crystal panel 32 and the third reflective liquid crystal panel 33, and images can be formed in the second reflective liquid crystal panel 32 and the third reflective liquid crystal panel 33, respectively. On the other hand, the optical path length from the cross-separation element 9 to the first reflective liquid crystal panel 31 corresponding to blue light is set to be longer than that of the red and green light. In this blue light optical path, a relay optical system 20 is provided so that an image can be formed once in the optical path and then re-imaged in the first reflective liquid crystal panel 31 via the relay optical system 20.

[0043] In this embodiment, the first, second, and third incident surfaces 31A, 32A, and 33A of the first, second, and third reflective liquid crystal panels 31, 32, and 33 are optically conjugate with the respective microlenses of the first lens array 6A. Therefore, the images of the respective microlenses of the first lens array 6A are superimposed on the first, second, and third incident surfaces 31A, 32A, and 33A of the first, second, and third reflective liquid crystal panels 31, 32, and 33. This makes the illuminance distribution at the first, second, and third incident surfaces 31A, 32A, and 33A of the first, second, and third reflective liquid crystal panels 31, 32, and 33 uniform.

[0044] The combining optical system 40 generates combined light by combining the first color light Lb optically modulated by the first reflective liquid crystal panel 31, the second color light Lr optically modulated by the second reflective liquid crystal panel 32, and the third color light Lg optically modulated by the third reflective liquid crystal panel 33. In this embodiment, the combining optical system 40 includes a cross dichroic prism. The combining optical system 40 has an incident surface 41 onto which the first color light Lb optically modulated by the first reflective liquid crystal panel 31 is incident, an incident surface 42 onto which the second color light Lr optically modulated by the second reflective liquid crystal panel 32 is incident, an incident surface 43 onto which the third color light Lg optically modulated by the third reflective liquid crystal panel 33 is incident, and an exit surface 46 from which the combined light is emitted.

[0045] The incident surface 41 is parallel to the XZ plane and faces in the -Y direction. The incident surface 42 is parallel to the XZ plane and faces in the +Y direction. The incident surface 43 is parallel to the YZ plane and faces in the -X direction. The exit surface 46 is parallel to the YZ plane and faces in the +X direction.

[0046] The combining optical system 40 has a first combining surface 44 that combines the first colored light Lb incident from the incident surface 41 and the third colored light Lg incident from the incident surface 43, and a second combining surface 45 that combines the third colored light Lg incident from the incident surface 43 and the second colored light Lr incident from the incident surface 42. The first combining surface 44 and the second combining surface 45 are parallel to the Z axis. The first combining surface 44 and the second combining surface 45 are orthogonal to each other.

[0047] The first combining surface 44 reflects the first color light Lb that has exited the first reflective liquid crystal panel 31 and entered the incident surface 41 via the second polarizer 62. The first combining surface 44 transmits the third color light Lg that has exited the third reflective liquid crystal panel 33 and entered the incident surface 43 via the sixth polarizer 66.

[0048] The second combining surface 45 transmits the third color light Lg that has exited from the third reflective liquid crystal panel 33 and entered through the incident surface 43 via the sixth polarizer 66. The second combining surface 45 reflects the second color light Lr that has exited from the second reflective liquid crystal panel 32 and entered through the incident surface 42 via the fourth polarizer 64.

[0049] The projection optical system 50 projects the combined light generated by the combining optical system 40 and emitted from the emission surface 46 onto the screen 70. The projection optical system 50 is optically conjugate with the second lens array 6B. The surface of the screen 70 is also optically conjugate with each of the multiple microlenses of the first lens array 6A.

[0050] Next, the operation of the projection display device 100 according to this embodiment will be described. Fig. 3 is a perspective view illustrating the operation of the projection display device 100 according to this embodiment. In this embodiment, when there is a bias in the intensity distribution of the light emitted from the light source device 1, the optical system of the projection display device 100 including the illumination optical system 10 is configured so that the bias in the light intensity distribution formed on the exit surface 46 side of the combining optical system 40 (the image plane side of the projection optical system 50) by the plurality of optical components arranged in the optical path of the first color light Lb, the bias in the light intensity distribution formed on the exit surface 46 side of the combining optical system 40 (the image plane side of the projection optical system 50) by the plurality of optical components arranged in the optical path of the second color light Lr, and the bias in the light intensity distribution formed on the exit surface 46 side of the combining optical system 40 (the image plane side of the projection optical system 50) by the plurality of optical components arranged in the optical path of the third color light Lg are consistent.

[0051] In the following description, the optical system composed of multiple optical components arranged in the optical path of the first color light Lb will be referred to as the first color light optical system 81, the optical system composed of multiple optical components arranged in the optical path of the second color light Lr will be referred to as the second color light optical system 82, and the optical system composed of multiple optical components arranged in the optical path of the third color light Lg will be referred to as the third color light optical system 83.

[0052] The first color optical system 81 includes a first color separation element 11 (cross separation element 9), a fourth reflector 16, a fifth reflector 17, a first reflector 13, a relay optical system 20, a focusing lens 25, a first polarizer 61, a second polarizer 62, and a first reflective liquid crystal panel 31.

[0053] The second-color optical system 82 includes a second-color separation element 12 (cross-separation element 9), a second reflective member 14, a condensing lens 26, a third polarizer 63, a fourth polarizer 64, and a second reflective liquid crystal panel 32.

[0054] The third-color optical system 83 includes a first-color separation element 11 (cross-separation element 9), a second-color separation element 12 (cross-separation element 9), a third-reflecting member 15, a focusing lens 27, a fifth-color polarizer 65, a sixth-color polarizer 66, and a third-reflective liquid crystal panel 33.

[0055] In this embodiment, the bias in the light intensity distribution of the light source device 1 formed on the exit surface 46 side of the synthetic optical system 40 by the first color light optical system 81, the bias in the light intensity distribution of the light source device 1 formed on the exit surface 46 side of the synthetic optical system 40 by the second color light optical system 82, and the bias in the light intensity distribution of the light source device 1 formed on the exit surface 46 side of the synthetic optical system 40 by the third color light optical system 83 are all consistent.

[0056] The operation of the first-color optical system 81 will now be explained. Light emitted from the light source device 1, homogenized in the integrator optical system 6 in a plane perpendicular to the optical axis of the integrator optical system 6, and passed through the condenser lens 8 is separated into first-color light Lb and light of a different wavelength in the first-color separation element 11 of the cross-separation element 9. The first-color light Lb is reflected in the XY plane by the first-color separation element 11. The first reflection of the first-color light Lb takes place in the first-color separation element 11.

[0057] The first color light Lb reflected by the first color separation element 11 is incident on the fourth reflecting member 16. The first color light Lb is reflected in the XY plane by the fourth reflecting member 16. A second reflection of the first color light Lb occurs in the fourth reflecting member 16. Here, the condenser lens 8 and the first focusing lens 21 of the relay optical system 20 focus the first color light Lb onto the reflective surface 17A of the fifth reflecting member 17. In the first color optical system 81, a first intermediate image of the light source image is formed on the reflective surface 17A of the fifth reflecting member 17. That is, the first imaging point in the first color optical system 81 is formed on the reflective surface 17A of the fifth reflecting member 17.

[0058] The first colored light Lb reflected by the fourth reflecting member 16 is incident on the fifth reflecting member 17. The first colored light Lb is reflected in the XY plane by the fifth reflecting member 17. The first colored light Lb is reflected a third time by the fifth reflecting member 17.

[0059] The first colored light Lb reflected by the fifth reflecting member 17 is incident on the first reflecting member 13. The first colored light Lb is reflected in the XZ plane by the first reflecting member 13. The first colored light Lb is reflected a fourth time by the first reflecting member 13.

[0060] The first color light Lb reflected by the first reflecting member 13 passes through the condenser lens 25, the first polarizer 61, and the second polarizer 62, and enters the first reflective liquid crystal panel 31. The first color light Lb is reflected in the -Z direction by the first reflective liquid crystal panel 31. The first color light Lb is reflected a fifth time by the first reflective liquid crystal panel 31.

[0061] Here, the second condenser lens 22 and the third condenser lens 23 of the relay optical system 20 condense the first color light Lb onto the first incident surface 31A of the first reflective liquid crystal panel 31. In the first color light optical system 81, a second intermediate image of the light source image is formed on the first reflective liquid crystal panel 31. That is, a second image point in the first color light optical system 81 is formed on the first incident surface 31A of the first reflective liquid crystal panel 31. The first lens array 6A and the first incident surface 31A of the first reflective liquid crystal panel 31 are optically conjugate.

[0062] The first color light Lb reflected by the first reflective liquid crystal panel 31 is incident on the second polarizer 62. The first color light Lb is reflected in the YZ plane by the second polarizer 62. The first color light Lb is reflected a sixth time by the second polarizer 62.

[0063] The first color light Lb reflected by the second polarizer 62 is incident on the incident surface 41 of the combining optical system 40 .

[0064] In this way, the first color light Lb is reflected six times by a plurality of optical components in the first color light optical system 81 and enters the combining optical system 40.

[0065] Reflection by optical components forms a mirror image of an image. A mirror image is an image of an object created by reflection from a plane mirror. In other words, a mirror image is an image in which only the left and right or top and bottom are reversed, and the object and its mirror image are in a plane-symmetric relationship.

[0066] Furthermore, the first color light Lb is condensed twice by the relay optical system 20. That is, the first color light Lb forms an image twice in the first color light optical system 81 and enters the combining optical system 40. An inverted image of the image is formed by the relay optical system 20. An inverted image is an image of an object formed through a convex lens or the like, and the image of the object and the inverted image have a relationship of rotational symmetry of 180° about the optical axis.

[0067] Next, the operation of second color light optical system 82 will be described. Light emitted from light source device 1, homogenized in a plane perpendicular to the optical axis of integrator optical system 6 by integrator optical system 6, and passed through condenser lens 8 is separated by second color separation element 12 of cross separation element 9 into second color light Lr and light of a different wavelength from second color light Lr. Second color separation element 12 reflects second color light Lr in the XY plane. Second color separation element 12 reflects second color light Lr a first time.

[0068] The second-color light Lr reflected by the second-color separation element 12 is incident on the second reflecting member 14. The second-color light Lr is reflected in the XZ plane by the second reflecting member 14. A second reflection of the second-color light Lr takes place in the second reflecting member 14.

[0069] The second color light Lr reflected by the second reflective member 14 passes through the focusing lens 26, the third polarizer 63, and the fourth polarizer 64 and enters the second reflective liquid crystal panel 32. The second color light Lr is reflected in the -Z direction by the second reflective liquid crystal panel 32. A third reflection of the second color light Lr takes place in the second reflective liquid crystal panel 32.

[0070] Here, the condenser lens 8 focuses the second color light Lr onto the second incident surface 32A of the second reflective liquid crystal panel 32. In the second color light optical system 82, an intermediate image of the light source image is formed on the second reflective liquid crystal panel 32. That is, the image point in the second color light optical system 82 is formed on the second incident surface 32A of the second reflective liquid crystal panel 32. The first lens array 6A and the second incident surface 32A of the second reflective liquid crystal panel 32 are optically conjugate.

[0071] The second-color light Lr reflected by the second-reflecting liquid crystal panel 32 is incident on the fourth polarizer 64. The second-color light Lr is reflected in the YZ plane by the fourth polarizer 64. The fourth reflection of the second-color light Lr takes place in the fourth polarizer 64.

[0072] The second color light Lr reflected by the fourth polarizer 64 is incident on the incident surface 42 of the combining optical system 40 .

[0073] In this way, the second color light Lr is reflected four times by multiple optical components in the second color light optical system 82 and then enters the combining optical system 40. The second color light Lr also forms an image once in the second color light optical system 82 and then enters the combining optical system 40.

[0074] Next, the operation of third color light optical system 83 will be described. Light is emitted from light source device 1, is homogenized in the integrator optical system 6 in a plane perpendicular to the optical axis of integrator optical system 6, passes through condenser lens 8, and is then separated into first color light Lb and second color light Lr, respectively, by first color separation element 11 and second color separation element 12 of cross separation element 9. Third color light Lg is transmitted through first color separation element 11 and second color separation element 12 (cross separation element 9).

[0075] The third color light Lg that has passed through the first color separation element 11 and the second color separation element 12 is incident on the third reflecting member 15. The third color light Lg is reflected in the YZ plane by the third reflecting member 15. The third color light Lg is reflected a first time by the third reflecting member 15.

[0076] The third color light Lg reflected by the third reflecting member 15 passes through the condenser lens 27, the fifth polarizer 65, and the sixth polarizer 66, and is incident on the third reflective liquid crystal panel 33. The third color light Lg is reflected in the -Z direction by the third reflective liquid crystal panel 33. The third color light Lg is reflected a second time by the third reflective liquid crystal panel 33.

[0077] Here, the condenser lens 8 collects the third color light Lg onto the third incident surface 33A of the third reflective liquid crystal panel 33. In the third color light optical system 83, an intermediate image of the light source image is formed on the third reflective liquid crystal panel 33. That is, the image point in the third color light optical system 83 is formed on the third incident surface 33A of the third reflective liquid crystal panel 33. The first lens array 6A and the third incident surface 33A of the third reflective liquid crystal panel 33 are optically conjugate.

[0078] The third color light Lg reflected by the third reflective liquid crystal panel 33 is incident on the sixth polarizer 66. The third color light Lg is reflected in the XZ plane by the sixth polarizer 66. The third color light Lg is reflected a third time by the sixth polarizer 66.

[0079] The third color light Lg reflected by the sixth polarizer 66 is incident on the incident surface 43 of the combining optical system 40 .

[0080] In this way, the third color light Lg is reflected three times by multiple optical components in the third color light optical system 83 and then enters the combining optical system 40. The third color light Lg also forms an image once in the third color light optical system 83 and then enters the combining optical system 40.

[0081] Next, changes in the bias of the light intensity distribution of the light source device 1 in each of the first color light optical system 81, the second color light optical system 82, and the third color light optical system 83 will be described with reference to FIG. 3. In the description using FIG. 3, to make the bias of the light intensity distribution easier to understand, the directionality (or orientation) of the light source image indicating the bias of the light intensity distribution is shown corresponding to the graphic orientation of the letter "F." Note that in FIG. 3, the letter "F" is also schematically drawn on each optical component, but the light source image, or more precisely, each image on each microlens of the first lens array 6A, is formed only on the corresponding conjugate plane. In other words, the light source image is formed on each of the third condenser lens 23, the first reflective liquid crystal panel 31, the second reflective liquid crystal panel 32, and the third reflective liquid crystal panel 33, which are positioned optically conjugate with the first lens array 6A. In the YZ plane, the +Z direction is set to be above "F," and in the optical axis direction, the direction of the light source image that allows "F" to be read in the correct orientation when viewed from the direction from the synthetic optical system 40 toward the screen 70 is set to be the reference direction.

[0082] The orientation of the light source image, which indicates the bias in the light intensity distribution in the first color light optical system 81, will now be described. The light source image is inverted by the action of the second lens array 6B. Furthermore, an inverted mirror image of the light source image is formed by reflection at the first color separation element 11 of the cross separation element 9. This mirror image is then reflected by the fourth reflecting member 16 and the fifth reflecting member 17. As a result, as shown in FIG. 3, the orientation of the light source image on the reflecting surface 17A of the fifth reflecting member 17 is rotated by 180° (inverted).

[0083] Furthermore, the orientation of the light source image is inverted by the action of second condenser lens 22 and third condenser lens 23 of relay optical system 20. As a result, the orientation of the light source image on reflecting surface 13A of first reflecting member 13 becomes a reference direction that is not inverted or rotated, as shown in FIG.

[0084] A mirror image of the light source image is formed by reflection on first reflecting member 13. As a result, the orientation of the light source image on first entrance surface 31A of first reflective liquid crystal panel 31 is upside down, as shown in FIG.

[0085] A mirror image of the light source image is formed by reflection from the first reflective liquid crystal panel 31. As a result, the orientation of the light source image on the reflective surface of the second polarizer 62 is rotated by 180° (inverted), as shown in FIG.

[0086] A mirror image of the light source image is formed by reflection at second polarizer 62. As a result, the orientation of the light source image is upside down at incident surface 41 of combining optical system 40, as shown in FIG.

[0087] Next, the orientation of the light source image, which indicates the bias in the light intensity distribution in the second color light optical system 82, will be described. As described above, the light source image is inverted by the action of the second lens array 6B. Furthermore, an inverted mirror image of the light source image is formed by reflection at the second color separation element 12 of the cross separation element 9. As a result, as shown in FIG. 3, the orientation of the light source image on the reflecting surface 14A of the second reflecting member 14 is rotated by 180° (inverted).

[0088] A mirror image of the light source image is formed by reflection on the second reflecting member 14. As a result, the orientation of the light source image on the second incident surface 32A of the second reflective liquid crystal panel 32 is upside down, as shown in FIG.

[0089] A mirror image of the light source image is formed by reflection from the second reflective liquid crystal panel 32. As a result, the orientation of the light source image is upside down on the reflective surface of the fourth polarizer 64, as shown in FIG.

[0090] A mirror image of the light source image is formed by reflection at the fourth polarizer 64. As a result, the orientation of the light source image at the incident surface 42 of the combining optical system 40 is a reference direction that is not inverted or rotated, as shown in FIG.

[0091] Next, the orientation of the light source image, which indicates the bias in the light intensity distribution in the third color light optical system 83, will be described. As described above, the light source image is inverted by the action of the second lens array 6B. After passing through the cross separation element 9, a mirror image of the light source image is formed by reflection on the third reflecting member 15. As a result, as shown in FIG. 3, the orientation of the light source image is upside down on the third entrance surface 33A of the third reflective liquid crystal panel 33.

[0092] A mirror image of the light source image is formed by reflection from the third reflective liquid crystal panel 33. The light source image is also inverted by the action of the condenser lens 8. As a result, as shown in FIG. 5, the orientation of the light source image on the reflective surface of the sixth polarizer 66 is a reference direction that is not inverted or rotated.

[0093] A mirror image of the light source image is formed by reflection at sixth polarizer 66. As a result, the orientation of the light source image is upside down at incident surface 43 of combining optical system 40, as shown in FIG.

[0094] The light source image formed on incident surface 41 and the light source image formed on incident surface 43 are combined at first combining surface 44 of combining optical system 40. As shown in FIG. 3 , the light source image formed on incident surface 41 and the light source image formed on incident surface 43 coincide with each other at first combining surface 44 of combining optical system 40.

[0095] The light source image formed on incident surface 42 and the light source image formed on incident surface 43 are combined at second combining surface 45 of combining optical system 40. As shown in FIG. 3 , the light source image formed on incident surface 42 and the light source image formed on incident surface 43 coincide with each other at second combining surface 45 of combining optical system 40.

[0096] Therefore, the orientation of the light source image formed on the exit surface 46 side of the synthetic optical system 40 by the first color light optical system 81, the orientation of the light source image formed on the exit surface 46 side of the synthetic optical system 40 by the second color light optical system 82, and the orientation of the light source image formed on the exit surface 46 side of the synthetic optical system 40 by the third color light optical system 83 are the same.

[0097] 3, in this embodiment, the orientation of the light source image incident on incident surface 41 and the orientation of the light source image incident on incident surface 43 are mirror-symmetric with respect to first synthesis surface 44, and the orientation of the light source image incident on incident surface 42 and the orientation of the light source image incident on incident surface 43 are mirror-symmetric with respect to second synthesis surface 45. Due to the relationship between the orientation of the light source image incident on incident surface 41 of synthesis optical system 40, the orientation of the light source image incident on incident surface 42, and the orientation of the light source image incident on incident surface 43, the orientations of the light source images of the color lights of each color emitted from synthesis optical system 40 match.

[0098] Next, we will explain the cooling mechanism of the projection display device 100. Fig. 4 is a plan view that schematically shows a part of the cooling mechanism that cools the projection display device 100 according to this embodiment, and Fig. 5 is a VV cross-sectional view of Fig. 4. Fig. 6 is a perspective view that schematically shows an example of a sealed box according to this embodiment.

[0099] As described above, the projection display device 100 includes the first reflective liquid crystal panel 31 corresponding to the first color light (blue light) Lb, the second reflective liquid crystal panel 32 corresponding to the second color light (red light) Lr, and the third reflective liquid crystal panel 33 corresponding to the third color light (green light) Lg. Because the first reflective liquid crystal panel 31, the second reflective liquid crystal panel 32, and the third reflective liquid crystal panel 33 generate heat during operation, these reflective liquid crystal panels need to be cooled effectively.

[0100] 4, the projection display device 100 includes a first cooling mechanism 91 thermally connected to the first reflective liquid crystal panel 31, a second cooling mechanism 92 thermally connected to the second reflective liquid crystal panel 32, and a third cooling mechanism 93 thermally connected to the third reflective liquid crystal panel 33. As shown in FIG. 5, the first cooling mechanism 91, the second cooling mechanism 92, and the third cooling mechanism 93 each include a heat sink having base plates 91A, 92A, and 93A thermally connected to the reflective liquid crystal panel via a support plate (plate material) 250, and a plurality of fins 91B, 92B, and 93B provided on the base plates 91A, 92A, and 93A, respectively.

[0101] The first cooling mechanism 91, the second cooling mechanism 92, and the third cooling mechanism 93 have base plates 91A, 92A, and 93A respectively attached to one surface 250a of the support plate 250. The first reflective liquid crystal panel 31, the second reflective liquid crystal panel 32, and the third reflective liquid crystal panel 33 are in contact with the other surface 250b of the support plate 250 at positions corresponding to the first cooling mechanism 91, the second cooling mechanism 92, and the third cooling mechanism 93, respectively. The support plate 250 is made of a material (such as stainless steel or glass) that has excellent thermal conductivity and is small in thermal fluctuations such as expansion and contraction due to heat. These first cooling mechanism 91, second cooling mechanism 92 and third cooling mechanism 93 dissipate heat from the first reflective liquid crystal panel 31, second reflective liquid crystal panel 32 and third reflective liquid crystal panel 33, respectively, thereby preventing excessive temperature rise in these first reflective liquid crystal panel 31, second reflective liquid crystal panel 32 and third reflective liquid crystal panel 33.

[0102] Furthermore, the projection display device 100 includes a first air supply mechanism 94 that supplies cooling air to a first cooling mechanism 91 (first reflective liquid crystal panel 31) and a third cooling mechanism 93 (third reflective liquid crystal panel 33), respectively, and a second air supply mechanism 95 that supplies cooling air to a second cooling mechanism 92 (second reflective liquid crystal panel 32). The first air supply mechanism 94 includes a first duct 96 that extends in the projection direction (along the X-axis) of the projection optical system 50, and a first fan 97 provided in this first duct 96. On the other hand, the second air supply mechanism 95 includes a second duct 98 that extends in parallel with the first air supply mechanism 94 in the projection direction (along the X-axis) of the projection optical system 50, and a second fan 99 provided in this second duct 98.

[0103] The first duct 96 is located on the +Z side of the first cooling mechanism 91 and the third cooling mechanism 93, and supplies cooling air to these two mechanisms, respectively. The inside of the first duct 96 is divided into two by a partition plate 96a that extends along the projection direction of the projection optical system 50. A distribution gate 86 is provided on the air inlet side of this partition plate 96a, and this distribution gate 86 is pivotable relative to the partition plate 96a. Therefore, by pivoting the distribution gate 86 relative to the partition plate 96a, the cooling air supplied to the first cooling mechanism 91 and the third cooling mechanism 93 can be distributed in a predetermined ratio (ratio of air flow rate (volume) per unit time). The distribution gate 86 may be configured to be manually repositioned and fixed, or it may be configured to have a drive unit (not shown) that adjusts the position of the distribution gate 86 according to the detected temperature of the first cooling mechanism 91 and the third cooling mechanism 93. Furthermore, as shown in Figure 5, the first duct 96 includes a first supply port 96b that opens toward the first cooling mechanism 91 and a third supply port (not shown) that opens toward the third cooling mechanism 93. Therefore, the air supplied to the first duct 96 by the drive of the first fan 97 is divided into two by the partition plate 96a and supplied to the first cooling mechanism 91 and the third cooling mechanism 93, respectively, through the first supply port 96b and the third supply port.

[0104] The second duct 98 is located on the +Z direction side of the second cooling mechanism 92, and supplies cooling air to the second cooling mechanism 92. As shown in FIG. 5 , the second duct 98 has a second supply port 98a that opens toward the second cooling mechanism 92. Therefore, air supplied to the second duct 98 by driving the second fan 99 is supplied to the second cooling mechanism 92 through the second supply port 98a. Although not shown, the second duct 98 extends to the light source device 1, and supplies air to cool the solid-state light sources 2 of the light source device 1.

[0105] Generally, the higher the light source output (light intensity) of each reflective liquid crystal panel, the higher the temperature of that panel tends to be. According to the inventor's extensive research, the first reflective liquid crystal panel 31 corresponding to the first colored light (blue light) Lb and the third reflective liquid crystal panel 33 corresponding to the third colored light (green light) Lg have different temperature values, but the temperature changes along a first temperature gradient, in which the slope of the temperature change relative to the change in light source output (light intensity) is approximately the same. Meanwhile, the second reflective liquid crystal panel 32 corresponding to the second colored light (red light) Lr changes temperature along a second temperature gradient, in which the slope of the temperature change relative to the change in light source output is different from the first temperature gradient. In other words, the second reflective liquid crystal panel 32 is found to have different temperature values ​​and slopes of the temperature change relative to the light source output from the first reflective liquid crystal panel 31 and the third reflective liquid crystal panel 33.

[0106] For this reason, this embodiment includes a first air supply mechanism 94 that supplies cooling air to the first cooling mechanism 91 and the third cooling mechanism 93, respectively, and a second air supply mechanism 95 that supplies cooling air to the second cooling mechanism 92. Therefore, by adjusting the airflow rate of the first fan 97 of the first air supply mechanism 94, the single first fan 97 can appropriately control the light source output (light intensity) and temperature of the first reflective liquid crystal panel 31 and the third reflective liquid crystal panel 33. Therefore, by independently controlling the first fan 97 of the first air supply mechanism 94 and the second fan 99 of the second cooling mechanism 92, the temperatures of the reflective liquid crystal panels can be kept uniform over a wide range of light source outputs for all of the colored light, namely, the first colored light (blue light) Lb, the second colored light (red light) Lr, and the third colored light (green light) Lg, thereby improving the accuracy of the projected image. The airflow of the first fan 97 of the first air supply mechanism 94 is distributed to the first reflective liquid crystal panel 31 and the third reflective liquid crystal panel 33 at an appropriate ratio by a distribution gate 86 (distribution mechanism) shown in FIG. 4. In this embodiment, the distribution ratio of the airflow to the third colored light (green light) Lg is increased. In this embodiment, the distribution gate 86 has been described as an example of a distribution mechanism, but the configuration is not limited to this as long as it can distribute the cooling air supplied to the first cooling mechanism 91 and the third cooling mechanism 93 at a predetermined ratio.

[0107] In this way, by using a single air supply mechanism to send air to LCD panels that have the same tendency for temperature change in relation to the light source output (light intensity), the air supply mechanism can be simplified compared to controlling each LCD panel with an independent fan.

[0108] Furthermore, in this embodiment, as shown in Figure 5, the projection display device 100 comprises a first sealed box 201 housing a first polarizer 61, a second polarizer 62, and a first reflective liquid crystal panel 31; a second sealed box 202 housing a third polarizer 63, a fourth polarizer 64, and a second reflective liquid crystal panel 32; and a third sealed box 203 (Figure 4) housing a fifth polarizer 65 (Figure 2), a sixth polarizer 66 (Figure 2), and a third reflective liquid crystal panel 33 (Figure 4). The projection display device 100 also includes a pair of support plates 250, 251 that sandwich and fix these first sealed box 201, second sealed box 202, and third sealed box 203 together in the Z direction. These support plates 250, 251 are made of a material (for example, stainless steel or glass) that has excellent thermal conductivity and exhibits small thermal fluctuations such as thermal expansion and contraction.

[0109] The first sealed box 201 includes an outer member 210 that supports the first polarizer 61 and the first reflective liquid crystal panel 31, and an inner member 220 that is positioned in the internal space H of the outer member 210 and supports the second polarizer 62. The inner member 220 is fixed to the outer member 210 in the internal space H. The projection display device 100 also includes a sealing mechanism 230 that seals the internal space H of the outer member 210.

[0110] As shown in Figure 5, the outer member 210 is a rectangular parallelepiped. The outer member 210 has a first aperture Ma through which the first color light Lb reflected by the first reflective member 13 of the illumination optical system 10 and incident on the first polarizer 61 passes; a second aperture Mb through which the first color light Lb transmitted through the first polarizer 61 and the second polarizer 62 and incident on the first reflective liquid crystal panel 31 passes; and a third aperture Mc through which the first color light Lb reflected by the second polarizer 62 and incident on the composite optical system 40 passes.

[0111] The outer member 210 is supported by the support plate 251 so that the first opening Ma faces the opening 251a of the support plate 251, and is supported by the support plate 250 so that the second opening Mb faces the support plate 250.

[0112] The sealing mechanism 230 has a first sealing member 231 that seals the first opening Ma, a second sealing member 232 that seals the second opening Mb, and a third sealing member 233 that seals the third opening Mc.

[0113] The first sealing member 231 seals the gap between the first polarizer 61 arranged in the first opening Ma and the outer member 210 around the first polarizer 61, thereby suppressing gas from flowing between the internal space H of the outer member 210 and the external space of the outer member 210 through the first opening Ma. The second sealing member 232 seals the gap between the first reflective liquid crystal panel 31 arranged in the second opening Mb and the outer member 210 around the first reflective liquid crystal panel 31, thereby suppressing gas from flowing between the internal space H of the outer member 210 and the external space of the outer member 210 through the second opening Mb. The third sealing member 233 seals the gap between the transmissive polarizer 67 arranged in the third opening Mc and the outer member 210 around the transmissive polarizer 67, thereby suppressing gas from flowing between the internal space H of the outer member 210 and the external space of the outer member 210 through the third opening Mc.

[0114] The first opening Ma, the second opening Mb and the third opening Mc are sealed by the first sealing member 231, the second sealing member 232 and the third sealing member 233, respectively, thereby preventing foreign matter in the external space of the outer member 210 from entering the internal space H of the outer member 210 through any of the first opening Ma, the second opening Mb and the third opening Mc.

[0115] As described above, the projection display device 100 includes the first sealed box 201 that houses and supports the first polarizer 61, the second polarizer 62, and the first reflective liquid crystal panel 31, the second sealed box 202 that houses and supports the third polarizer 63, the fourth polarizer 64, and the second reflective liquid crystal panel 32, and the third sealed box 203 that houses and supports the fifth polarizer 65, the sixth polarizer 66, and the third reflective liquid crystal panel 33, and these first sealed box 201, second sealed box 202, and third sealed box 203 are arranged around the combining optical system 40. In this type of projection display device 100, it is important to appropriately maintain the relative positional relationship of the first sealed box 201, second sealed box 202, and third sealed box 203 with respect to the combining optical system 40 in order to reduce positional deviations of the optical components and improve the quality of the image projected by the projection optical system 50.

[0116] In this embodiment, the projection type display device 100 is equipped with a pair of support plates 250, 251 that sandwich the first sealed box 201, the second sealed box 202 and the third sealed box 203 in the Z direction and fix them together, and are made of a material with little thermal fluctuation.Therefore, the relative positional relationship of the first sealed box 201, the second sealed box 202 and the third sealed box 203 with respect to the composite optical system 40 can be properly maintained, and the image quality of the image projected by the projection optical system 50 can be improved.

[0117] As described above, projection display device 100 according to this embodiment has first color separation element 11 and second color separation element 12 arranged to intersect with each other, and reflects blue light having a long wavelength from the light emitted from light source device 1 by first color separation element 11 and emits it in a first direction parallel to a first axis in a predetermined plane, reflects red light having a short wavelength from the light emitted from light source device 1 by second color separation element 12 and emits it in a direction opposite to the blue light in the first direction, and transmits green light having a wavelength between the blue light and red light from the light emitted from light source device 1 through first color separation element 11 and second color separation element 12 and emits it in a second direction parallel to a second axis perpendicular to the first axis in the predetermined plane. The projection display device 100 is equipped with a cross separation element 9 that emits blue light, and a relay optical system 20 that is arranged in the optical path of the blue light between the cross separation element 9 and the first reflective liquid crystal panel 31 and forms an erect image, and the optical path lengths of the red light and green light from the cross separation element 9 to the second reflective liquid crystal panel 32 and the third reflective liquid crystal panel 33 are made the same, so that the light emitted from the light source device 1 can be separated into blue light, red light and green light by the cross separation element 9, and the blue light, red light and green light can be imaged on the first reflective liquid crystal panel 31, the second reflective liquid crystal panel 32 and the third reflective liquid crystal panel 33, respectively, thereby enabling the device configuration of the projection display device 100 to be made more compact.

[0118] Furthermore, in the projection display device 100 of this embodiment, when projected by the projection optical system 50, the blue light, red light, and green light have the same direction of bias in the light intensity distribution of each color light formed on the exit surface side. Therefore, even if a bias occurs in the illuminance distribution of the first color light Lb irradiated to the first incident surface 31A of the first reflective liquid crystal panel 31, a bias occurs in the illuminance distribution of the second color light Lr irradiated to the second incident surface 32A of the second reflective liquid crystal panel 32, or a bias occurs in the illuminance distribution of the third color light Lg irradiated to the third incident surface 33A of the third reflective liquid crystal panel 33 due to at least one of, for example, an installation error of the solid-state light source 2, a fluctuation in the position of the solid-state light source 2, an installation error of the phosphor 3, a fluctuation in the position of the phosphor 3, an installation error of the half mirror 4, a fluctuation in the position of the half mirror 4, an installation error of the focusing optical system 5, and a fluctuation in the position of the focusing optical system 5, it is possible to suppress the occurrence of color unevenness in the image projected by the projection optical system 50.

[0119] In addition, the projection display device 100 of this embodiment is equipped with a condenser lens 8 that is provided between the light source device 1 and the cross separation element 9 and that adjusts the direction of bias in the light intensity distribution of the red light and green light separated by the cross separation element 9 by adjusting the light emitted from the light source device 1, and a third condenser lens 23 that is provided in the relay optical system 20 and that adjusts the direction of bias in the light intensity distribution of the blue light separated by the cross separation element 9.Therefore, when projected by the projection optical system 50, the blue light, red light, and green light can each have the same direction of bias in the light intensity distribution of each color light formed on the emission surface side.

[0120] Furthermore, the projection display device 100 of this embodiment comprises a first cooling mechanism 91 thermally connected to the first reflective liquid crystal panel 31, a second cooling mechanism 92 thermally connected to the second reflective liquid crystal panel 32, a third cooling mechanism 93 thermally connected to the third reflective liquid crystal panel 33, a first air supply mechanism 94 that supplies cooling air to the first cooling mechanism 91 and the third cooling mechanism 93, respectively, and a second air supply mechanism 95 arranged in parallel with the first air supply mechanism 94 that supplies cooling air to the second cooling mechanism 92. Therefore, by adjusting the airflow rate of the first air supply mechanism 94, the light source output (light intensity) and temperature of the first reflective liquid crystal panel 31 and the third reflective liquid crystal panel 33 can be appropriately controlled using, for example, a single first fan 97. Therefore, by independently controlling the airflow rate of the first air supply mechanism 94 and the airflow rate of the second cooling mechanism 92, the temperature of each reflective liquid crystal panel can be kept uniform over a wide range of light source output for all colors of light, namely, the first color light (blue light) Lb, the second color light (red light) Lr, and the third color light (green light) Lg, thereby improving the accuracy of the projected image.

[0121] The projection display device 100 of this embodiment comprises a first sealed box 201 accommodating a first polarizer 61, a first reflective liquid crystal panel 31, and a second polarizer 62, a second sealed box 202 accommodating a third polarizer 63, a second reflective liquid crystal panel 32, and a fourth polarizer 64, a third sealed box 203 accommodating a fifth polarizer 65, a third reflective liquid crystal panel 33, and a sixth polarizer 66, and a pair of support plates 250, 251 that sandwich and fix the first sealed box 201, the second sealed box 202, and the third sealed box 203 together, thereby making it possible to appropriately maintain the relative positional relationship of the first sealed box 201, the second sealed box 202, and the third sealed box 203 with respect to the synthesis optical system 40, and thereby improving the image quality of the image projected by the projection optical system 50.

[0122] The projection display device 100 of this embodiment comprises a first cooling mechanism 91 connected to the first reflective liquid crystal panel 31, a second cooling mechanism 92 connected to the second reflective liquid crystal panel 32, and a third cooling mechanism 93 connected to the third reflective liquid crystal panel 33. The first cooling mechanism 91, the second cooling mechanism 92, and the third cooling mechanism 93 are supported on one of the support plates 250, and therefore the first cooling mechanism 91, the second cooling mechanism 92, and the third cooling mechanism 93 dissipate heat from the first reflective liquid crystal panel 31, the second reflective liquid crystal panel 32, and the third reflective liquid crystal panel 33, respectively, thereby suppressing excessive temperature rise in the first reflective liquid crystal panel 31, the second reflective liquid crystal panel 32, and the third reflective liquid crystal panel 33.

[0123] In the projection display device 100 according to this embodiment, the first sealed box 201 includes an outer member 210 that supports the first polarizer 61 and the first reflective liquid crystal panel 31, an inner member 220 that is fixed to the outer member 210 in the internal space H of the outer member 210 and supports the second polarizer 62, and a sealing mechanism 230 that seals the internal space H. Therefore, the first polarizer 61 and the first reflective liquid crystal panel 31 are supported by the outer member 210, which is a single member. Because the internal space H of the outer member 210 is sealed by the sealing mechanism 230, foreign matter is prevented from entering the internal space H. This prevents foreign matter from adhering to the first incident surface 31A of the first reflective liquid crystal panel 31 and the reflective surface of the second polarizer 62.

[0124] Furthermore, in the projection display device 100 according to this embodiment, the first color light Lb is incident on the first reflective liquid crystal panel 31 by the first reflecting member 13, which reflects the first color light Lb in the +Z direction. The second color light Lr is incident on the second reflective liquid crystal panel 32 by the second reflecting member 14, which reflects the second color light Lr in the +Z direction. The third color light Lg is incident on the third reflective liquid crystal panel 33 by the third reflecting member 15, which reflects the third color light Lg in the +Z direction. This allows the projection display device 100 to be made compact. Furthermore, since no optical components are disposed on the rear sides of the first, second, and third reflective liquid crystal panels 31, 32, and 33, for example, a first cooling mechanism 91 and a third cooling mechanism 93 for cooling the first, second, and third reflective liquid crystal panels 31, 32, and 33 can be provided on the rear sides of the first, second, and third reflective liquid crystal panels 31, 32, and 33.

[0125] Furthermore, in the projection-type display device 100 according to this embodiment, the relay optical system 20 is arranged between the first color separation element 11 and the first reflective member 13. Therefore, the structure of the optical system arranged in the optical path of the first color light Lb from the first reflective member 13 to the incident surface 41 of the composite optical system 40 in the first color light optical system 81, the structure of the optical system arranged in the optical path of the second color light Lr from the second reflective member 14 to the incident surface 42 of the composite optical system 40 in the second color light optical system 82, and the structure of the optical system arranged in the optical path of the third color light Lg from the third reflective member 15 to the incident surface 43 of the composite optical system 40 in the third color light optical system 83 can be made uniform.

[0126] Furthermore, the projection display device 100 according to this embodiment includes a first air supply mechanism 94 that supplies cooling air to the first reflective liquid crystal panel 31 and the third reflective liquid crystal panel 33, respectively, and a second air supply mechanism 95 that supplies cooling air to the second reflective liquid crystal panel 32. The first reflective liquid crystal panel 31 and the third reflective liquid crystal panel 33 each change along the same first temperature gradient in response to changes in light source output, while the second reflective liquid crystal panel 32 changes along a second temperature gradient different from the first temperature gradient in response to changes in light source output. The device includes a distribution gate 86 that distributes the cooling air supplied to the first reflective liquid crystal panel 31 and the third reflective liquid crystal panel 33 in a predetermined ratio. By cooling panels with the same temperature change trend in response to changes in light source output using a single first air supply mechanism 94, the device configuration can be simplified. Furthermore, by adjusting the distribution ratio of the cooling air from the first air supply mechanism 94, the light source output (light intensity) and temperature of the first reflective liquid crystal panel 31 and the third reflective liquid crystal panel 33 can be appropriately controlled using a single first fan 97. Therefore, by independently controlling the first fan 97 of the first air supply mechanism 94 and the second fan 99 of the second cooling mechanism 92, the temperature of each reflective liquid crystal panel can be kept uniform across a wide range of light source output for all colors of light: first color light (blue light) Lb, second color light (red light) Lr, and third color light (green light) Lg, thereby improving the accuracy of the projected image.

[0127] In the projection display device 100 of this embodiment, the first reflective liquid crystal panel 31, the second reflective liquid crystal panel 32, and the third reflective liquid crystal panel 33 are each arranged on three sides of the synthetic optical system 40, excluding the projection direction of the projection optical system 50, in a planar view. The first reflective liquid crystal panel 31 and the second reflective liquid crystal panel 32 are arranged facing each other across the synthetic optical system 40, and the third reflective liquid crystal panel 33 is arranged on the opposite side of the projection optical system 50 across the synthetic optical system 40. Therefore, the first air supply mechanism 94, which supplies cooling air to the first reflective liquid crystal panel 31 and the third reflective liquid crystal panel 33, respectively, and the second air supply mechanism 95, which supplies cooling air to the second reflective liquid crystal panel 32, can be arranged compactly.

[0128] In the projection display device 100 of this embodiment, the first color light Lb is blue light, the second color light Lr is red light, and the third color light Lg is green light. Therefore, by adjusting the distribution ratio of cooling air between the first reflective liquid crystal panel 31 for blue light and the third reflective liquid crystal panel 33 for green light, which have the same change in temperature relative to changes in light source output, it is possible to easily control the light source output and temperature.

[0129] The configuration of the projection display device 100 according to this embodiment has been described above, but the configuration of the projection display device 100 is not limited to the embodiment described above. [Explanation of symbols]

[0130] 1 Light source device 9 Cross isolation element 11 First color separation element 12 Second color separation element 20 Relay optical system 31 First reflective LCD panel 32 Second reflective LCD panel 33 Third reflective LCD panel 40 Synthetic optical system 50 Projection optical system 61 First polarizer 62 Second polarizer 63 Third polarizer 64 4th polarizer 65 5th polarizer 66 6th polarizer 70 screens 86 Distribution gate (distribution mechanism) 91 1st cooling mechanism 91A Base Plate 91B Fin 92 Second cooling mechanism 93 Third cooling mechanism 94 First air supply mechanism 95 Second air supply mechanism 96 First Duct 96a Partition 96b 1st supply port 97 First Fan 98 Second Duct 98a Second supply port 99 Second Fan 100 Projection display device 201 First sealed box 202 Second sealed box 203 Third sealed box 210 Outer member 220 Inner member 230 Sealing mechanism H Internal space Lb first color light Lr second color light Lg 3rd color light

Claims

1. a cross separation element having a first color separation element and a second color separation element arranged to intersect with each other, wherein blue light having a long wavelength from the light emitted from a light source device is reflected by the first color separation element and emitted in a first direction parallel to a first axis in a predetermined plane, red light having a short wavelength from the light emitted from the light source device is reflected by the second color separation element and emitted in a direction opposite to the blue light in the first direction, and green light having a wavelength between the blue light and the red light from the light emitted from the light source device is transmitted through the first color separation element and the second color separation element and emitted in a second direction parallel to a second axis orthogonal to the first axis in the predetermined plane; a first reflecting member that reflects the blue light reflected by the first color separation element in a third direction parallel to a third axis that is perpendicular to the predetermined plane; a second reflecting member that reflects the red light reflected by the second color separation element in the third direction; a third reflecting member that reflects the green light that has passed through the first color separation element and the second color separation element in the third direction; a first reflective liquid crystal panel having a first incident surface onto which the blue light reflected by the first reflecting member is incident, and optically modulating the blue light based on image data; a second reflective liquid crystal panel having a second incident surface onto which the red light reflected by the second reflecting member is incident, and optically modulating the red light based on the image data; a third reflective liquid crystal panel having a third incident surface onto which the green light reflected by the third reflecting member is incident, and optically modulating the green light based on the image data; a combining optical system that combines the blue light optically modulated by the first reflective liquid crystal panel, the red light optically modulated by the second reflective liquid crystal panel, and the green light optically modulated by the third reflective liquid crystal panel to generate combined light; a projection optical system that projects the combined light generated by the combining optical system; a relay optical system that is disposed in an optical path of the blue light between the cross separation element and the first reflective liquid crystal panel and forms an erect image; wherein the optical path lengths of the red light and the green light from the cross separation element to the second reflective liquid crystal panel and the third reflective liquid crystal panel are the same.

2. 2. The projection display device according to claim 1, wherein when projected by the projection optical system, the blue light, the red light, and the green light have the same direction of bias in the light intensity distribution of each color light formed on the exit surface side.

3. a first optical component provided between the light source device and the cross separation element, which adjusts the direction of bias in the light intensity distribution of the red light and the green light separated by the cross separation element by adjusting the light emitted from the light source device; 3. The projection display device according to claim 1, further comprising: a second optical component provided in the relay optical system, which adjusts the direction of bias in the light intensity distribution of the blue light separated by the cross separation element.

4. a first cooling mechanism thermally connected to the first reflective liquid crystal panel, a second cooling mechanism thermally connected to the second reflective liquid crystal panel, and a third cooling mechanism thermally connected to the third reflective liquid crystal panel; 3. The projection display device according to claim 1, further comprising: a first air supply mechanism that supplies cooling air to the first cooling mechanism and the third cooling mechanism, respectively; and a second air supply mechanism that is arranged in parallel with the first air supply mechanism and supplies cooling air to the second cooling mechanism.

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