Light source device and projection type image display device

Abstract

To provide a light source device for projection type image display devices, with which it is made possible to suppress foreign matter such as dust from adhering to the optical elements of an optical system while replacing light sources.SOLUTION: A light source device 20 comprises: a first housing 92 that demarcates a closed space S2 and includes a first transmission window 96 and a second transmission window 52; a light source 28 that is disposed to the outside of the closed space S2 of the first housing 92 and emits light L0 in such a way as to pass through the first transmission window 96 and enter the inside of the closed space S2 of the first housing 92; and an output light generating optical system 32 that is accommodated in the closed space S2 of the first housing 92, generates prescribed output light Lw from the light L0 having passed through the first transmission window 96, and causes the output light Lw to pass through the second transmission window 52 and to be emitted to the outside of the closed spate S2 of the first housing 92.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present disclosure relates to a light source device and a projection type image display device including a light source device. [Background technology]

[0002] Patent Document 1 discloses a projection type image display device in which the light source is easily replaceable. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] JP 2015-179227 A Summary of the Invention [Problem to be solved by the invention]

[0004] However, in the case of the projection type image display device described in Patent Document 1, when the light source is removed for replacement, there is a possibility that foreign matter such as dust may adhere to the optical elements constituting the optical system that guides the light output from the light source. When foreign matter adheres to the optical elements, the light output deteriorates. For example, uneven brightness occurs in the projected image light.

[0005] In view of the above, an object of the present disclosure is to provide a light source device for a projection type image display device that is capable of replacing a light source while suppressing adhesion of foreign matter such as dust to optical elements of an optical system. [Means for solving the problem]

[0006] In order to solve the above-mentioned problems, according to one aspect of the present disclosure, No. a first housing having a first transmission window and a second transmission window; The first housing Outside and a light beam passing through the first transmission window is projected onto the first housing. inside the body A light source that emits light so as to enter the The first case On the bodya first housing, a second housing, a light source, a light source for receiving the light, and a light source for receiving the light from the first housing. Outside and an output light generating optical system for emitting light to the target portion. death, The output light generating optical system includes a phosphor wheel device including a reflective substrate that converts blue light into yellow light and reflects the yellow light. SUMMARY OF THE DISCLOSURE A light source device is provided.

[0007] According to another aspect of the present disclosure, The light source device described above; an image forming module that converts output light of the light source device into image light; and a projection optical system that projects image light from the image forming module. Effect of the Invention

[0008] According to the present disclosure, in a light source device of a projection type image display device, it is possible to replace the light source while suppressing adhesion of foreign matter to optical elements of the optical system. [Brief description of the drawings]

[0009] [Figure 1] FIG. 1 is a schematic configuration diagram showing a projection type image display device including a light source device according to a first embodiment of the present disclosure; [Diagram 2] FIG. 2 is a schematic diagram showing a light source device in a state where the light source module and the output light generating module are separated from each other; [Diagram 3] FIG. 13 is a schematic configuration diagram showing a light source device according to a second embodiment of the present disclosure in a state in which the light source module and the output light generating module are separated from each other; [Figure 4] FIG. 11 is a schematic configuration diagram showing a light source device according to a third embodiment of the present disclosure. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0010] A light source device according to one embodiment of the present disclosure includes a first housing defining an enclosed space and having a first transparent window and a second transparent window; a light source disposed outside the enclosed space of the first housing and emitting light to pass through the first transparent window and enter the enclosed space of the first housing; and an output light generating optical system contained in the enclosed space of the first housing, generating a predetermined output light from the light that has passed through the first transparent window, and transmitting the output light through the second transparent window to emit it to the outside of the enclosed space of the first housing.

[0011] According to this aspect, in the light source device of the projection type image display device, it is possible to replace the light source while suppressing adhesion of foreign matter to the optical elements of the optical system.

[0012] For example, the light source device may further include a second housing including the light source, wherein the second housing is detachably attached to the first housing such that the light source faces the first transmission window.

[0013] For example, the light source may be housed in an enclosed space defined by cooperation between the first housing and the second housing in a state in which the second housing is attached to the first housing.

[0014] For example, the second housing may define an enclosed space that houses the light source.

[0015] For example, the light source may emit blue light as the light, and the output light generating optical system may include a phosphor wheel device including a reflective substrate that converts the blue light into yellow light and reflects it. In this case, the output light generating optical system splits the blue light from the light source into a first blue light and a second blue light, guides the first blue light toward the reflective substrate, and generates white light as the output light by combining the yellow light reflected from the reflective substrate and the second blue light.

[0016] For example, the light source may emit blue light as the light, and the light source device may further include a phosphor wheel device disposed outside the first housing and including a reflective substrate that converts the blue light into yellow light and reflects it. In this case, the first housing may further include a third transmission window facing the reflective substrate. The output light generating optical system may split the blue light from the light source into a first blue light and a second blue light, guide the first blue light to pass through the third transmission window toward the reflective substrate, and generate white light as the output light by combining the yellow light reflected from the reflective substrate and transmitted through the third transmission window with the second blue light.

[0017] In addition, a projection type image display device of another aspect of the present disclosure has the above-mentioned light source device, an image forming module that converts the output light of the light source device into image light, and a projection optical system that projects the image light from the image forming module.

[0018] According to this aspect, in the light source device of the projection type image display device, it is possible to replace the light source while suppressing adhesion of foreign matter to the optical elements of the optical system.

[0019] Hereinafter, the embodiments will be described in detail with reference to the drawings as appropriate. However, more detailed explanation than necessary may be omitted. For example, detailed explanation of already well-known matters or duplicate explanation of substantially the same configuration may be omitted. This is to avoid the following explanation becoming unnecessarily redundant and to facilitate understanding by those skilled in the art.

[0020] It should be noted that the accompanying drawings and the following description are provided to enable those skilled in the art to fully understand the present disclosure, and are not intended to limit the subject matter described in the claims.

[0021] (Embodiment 1) FIG. 1 is a schematic configuration diagram showing a projection type image display device including a light source device according to a first embodiment of the present disclosure.

[0022] As shown in FIG. 1, a projection type image display device 10 is made up of a light source device 20 and a projection device 60 that creates and projects image light.

[0023] In the first embodiment, the light source device 20 includes a light source module 22 and an output light generating module .

[0024] The light source module 22 of the light source device 20 includes a substrate 26, a plurality of laser elements 28 (light sources) provided on the substrate 26, and a collimator lens 30 provided for each of the laser elements 28, which converts the laser light emitted from the laser elements 28 into parallel light. In the case of the first embodiment, the laser elements 28 are semiconductor laser elements that emit blue laser light. For example, 40 to 60 laser elements 28 are arranged in a matrix on the substrate 26. As a result, high-luminance blue laser light L0 is output from the light source module 22 toward the output light generating module 24.

[0025] The output light generating module 24 is a module that generates a predetermined output light that is finally output by the light source device 20 from the laser light L0 output by the light source module 22. In the case of the first embodiment, the output light generating module 24 includes an output light generating optical system 32 for generating white light Lw from the blue laser light L0 output by the light source module 22. The output light generating optical system 32, which will be described in detail later, is configured to split the blue laser light L0 from the light source module 22 into a first blue light L1 and a second blue light L2, convert the first blue light L1 into yellow light, and generate white light Lw by combining the yellow light and the second blue light L2. For this purpose, the output light generating optical system 32 includes, as its components, a diffusion plate 34, a quarter-wave plate 36, a dichroic mirror 38, a phosphor wheel device 40, a lens 42, a lens 44, a lens 46, a quarter-wave plate 48, and a mirror 50.

[0026] The diffusion plate 34 is a flat glass plate having a diffusion surface formed of fine concaves and convexes on one side thereof. The diffusion plate 34 eliminates unevenness in the luminance of the blue laser light L0 outputted from the light source module 22.

[0027] The quarter-wave plate 36 is an optical element that generates a phase difference of a quarter wavelength between two perpendicularly polarized components of the blue laser light L0 emitted from the diffusion plate 34. The quarter-wave plate 36 polarizes the blue laser light L0 emitted from the diffusion plate 34 from a linearly polarized state to an elliptically polarized state.

[0028] Dichroic mirror 38 is an optical element that splits blue laser light L0 emitted from quarter-wave plate 36, and is disposed at an angle of approximately 45 degrees with respect to the emission direction of blue laser light L0 emitted from quarter-wave plate 36. Dichroic mirror 38 reflects S-polarized component (first blue light) L1 of blue laser light L0 toward phosphor wheel device 40, and transmits P-polarized component (second blue light) L2.

[0029] Phosphor wheel device 40 is a device that converts blue light into yellow light, and includes reflective substrate 40a and motor 40b that rotates reflective substrate 40a. Yellow phosphor layer 40c is formed on reflective substrate 40a. Lenses 42, 44 arranged between dichroic mirror 38 and phosphor wheel device 40 focus S-polarized component L1 of the blue laser light reflected from dichroic mirror 38 on yellow phosphor layer 40c on reflective substrate 40a. The portion of yellow phosphor layer 40c on which the light is focused is excited and emits yellow light. The yellow light is collimated by lenses 42, 44 and then passes through dichroic mirror 38.

[0030] On the other hand, the P polarized component L2 of the blue laser light that has passed through the dichroic mirror 38 is focused on the mirror 50 by the lens 46. Before reaching the mirror 50, the P polarized component L2 of the blue laser light is transformed into a circularly polarized state by passing through the quarter-wave plate 48. The P polarized component L2 of the blue light reflected by the mirror 50 is again transmitted in the opposite direction through the quarter-wave plate 48 and converted into S polarized light. The S polarized light is then collimated by the lens 46 and reflected by the dichroic mirror 38.

[0031] The yellow light from phosphor wheel device 40 that has been transmitted through dichroic mirror 38 and the blue light L2 from mirror 50 that has been reflected by dichroic mirror 38 are combined to generate white light Lw. White light Lw travels toward condenser lens 52. White light Lw is output from condenser lens 52 toward projection device 60.

[0032] In the case of this embodiment 1, the projection device 60 includes a lens 62, a rod integrator 64, a lens 66, a lens 68, a mirror 70, a lens 72, a prism 74, an image forming module 76, and a projection optical system 78 to generate image light from the white light Lw output by the light source device 20 and project the image light.

[0033] The white light Lw emitted from the condenser lens 52 of the light source device 20 enters the projection device 60 via the lens 62. The white light Lw emitted from the lens 62 passes through the rod integrator 64, the lens 66, and the lens 68 in this order, and is reflected by the mirror 70. The reflected white light Lw passes through the lens 72 and the prism 74 and enters the image forming module 76.

[0034] The image forming module 76 is a module that converts the white light Lw into image light, and for that purpose, the image forming module 76 includes a prism assembly 86 that is composed of three prisms 80, 82, and 84, and three digital micromirror devices (DMDs) 88R, 88G, and 88B.

[0035] The prism assembly 86 is a so-called TIR (Total Internal Reflection) prism, and is configured to reflect light of a specific wavelength (specific color) at the interfaces between the prisms 80 to 84. As a result, the prism assembly 86 separates the white light Lw from the prism 74 into red light Lr, green light Lg, and blue light Lb. The prism assembly 86 also emits the separated red light Lr, green light Lg, and blue light Lb toward the digital micromirror devices 88R, 88G, and 88B. Furthermore, the prism assembly 86 combines the modulated light (red image light, green image light, and blue image light) reflected from each of the digital micromirror devices 88R, 88G, and 88B, and outputs the combined modulated light (full-color image light) toward the projection optical system 78.

[0036] Each of the digital micromirror devices 88R, 88G, and 88B is a light modulation device including a plurality of micromirrors that selectively reflect light in a plurality of directions. Each of the digital micromirror devices 88R, 88G, and 88B modulates the red light Lr, green light Lg, and blue light Lb emitted from the prism assembly 86, and reflects the modulated light (image light) toward the prism assembly 86.

[0037] The projection optical system 78 is an optical system including at least a projection lens, and projects the full-color image light emitted from the image forming module 76 onto, for example, a screen.

[0038] So far, the configuration of the projection type image display device according to an embodiment of the present disclosure has been described. From here on, further features of the light source device will be described.

[0039] As shown in FIG. 1, in the light source device 20, an output light generating optical system 32 including a plurality of laser elements 28 (light source) and a dichroic mirror 38 that generates white light Lw from the blue laser light L0 emitted by the plurality of laser elements 28 is contained in spaces S1 and S2 that are independent of each other.

[0040] FIG. 2 is a schematic diagram showing a light source device in a state where the light source module and the output light generating module are separated from each other.

[0041] As shown in FIGS. 1 and 2, in the first embodiment, the light source module 22 includes a housing 90 (second housing) that defines a space S1 in which the substrate 26, the multiple laser elements 28, and the collimating lens 30 are housed.

[0042] Moreover, the output light generating module 24 includes a housing 92 (first housing) that defines a space S2 that houses the output light generating optical system 32 including the dichroic mirror 38 and the like.

[0043] The housing 90 of the light source module 22 is detachably attached to the housing 92 of the output light generating module 24. The substrate 26 and the collimating lens 30 are supported by the housing 90. In the case of the first embodiment, the housing 90 has an opening 90a communicating with the space S1. When the housing 90 is attached to the housing 92 of the output light generating module 24, the opening 90a of the housing 90 is covered by the outer surface of the housing 92. By such cooperation of the housings 90 and 92, the space S1 in which the multiple laser elements 28 and the like are accommodated becomes a substantially sealed space, and the multiple laser elements 28 and the like are protected. Note that a sealing ring 94 made of an elastic material such as silicone rubber is disposed between the housing 90 and the housing 92 to prevent foreign matter such as dust from entering the space S1 through a gap between the housings 90 and 92. Although not shown, a cooling device such as a heat sink for cooling the laser element 28 is provided on the outer surface of the housing 90.

[0044] The housings 90 and 92 are positioned relative to each other, for example, via a positioning pin and a positioning hole, and are detachably fixed to each other, for example, via a fixing screw.

[0045] Housing 92 of output light generating module 24 defines a substantially sealed space S2 in which intrusion of foreign matter such as dust is suppressed. Within sealed space S2, output light generating optical system 32 including dichroic mirror 38 that generates white light Lw from blue laser light L0 output by light source module 22 is housed. Although not shown, a cooling device such as a heat sink for cooling phosphor wheel device 40 is provided on the outer surface of housing 92.

[0046] The housing 92 is provided with a transmission window 96 (first transmission window) so that the blue laser light L0 output from the light source module 22 can enter the space S2. The transmission window 96 is made of, for example, a glass plate. The transmission window 96 is disposed in a portion of the housing 92 facing the laser elements 28 when the housing 90 of the light source module 22 is attached to the housing 92 of the output light generating module 24. The transmission window 96 is fitted into a through hole formed in the housing 92. The gap between the transmission window 96 and the housing 92 is blocked by an adhesive or the like. By passing through such a transmission window 96, the laser light L0 emitted by the laser element 28 disposed outside the space S2 of the housing 92 in the sealed state can enter the space S2 of the housing 92 in the sealed state.

[0047] The white light Lw generated by the output light generation optical system 32 in the space S2 of the housing 92 passes through the condenser lens 52 and is emitted to the outside of the sealed space S2 of the housing 92. In the case of the first embodiment, the condenser lens 52 functions as a second transmission window. The condenser lens 52 is fitted into a through hole formed in the housing 92 of the output light generation module 24. In addition, the gap between the condenser lens 52 and the housing 92 is sealed with an adhesive or the like. By passing through such a condenser lens 52, the output light (white light Lw) generated by the output light generation optical system 32 can proceed to the outside of the sealed space S2 of the housing 92. In addition to the condenser lens 52, a transmission window made of a glass plate similar to the transmission window 96 may be provided in the housing 92.

[0048] Therefore, the blue laser light L0 emitted from the laser element 28 of the light source module 22 passes through the transmission window 96 and enters the sealed space S2 of the housing 92. The output light generating optical system 32 in the space S2 generates white light Lw from the blue laser light L0 that has entered, and transmits the generated white light Lw through the condenser lens 52 to be emitted to the outside of the space S2. As a result, the white light Lw is output to the outside of the space S2 of the housing 92 as the output light of the light source device 20.

[0049] According to such a housing structure of the light source device 20, the output light generating optical system 32 (a plurality of optical elements constituting the output light generating optical system 32), including the dichroic mirror 38 that generates the white light Lw from the blue laser light L0 emitted by the plurality of laser elements 28, is accommodated in a sealed space S2 defined by the housing 92. When the plurality of laser elements 28 are replaced due to a reason such as the end of their life, the optical elements of the output light generating optical system 32 are not exposed to the outside of the space S2 of the housing 92. That is, the space S2 does not communicate with the space outside the housing 92. As a result, when the plurality of laser elements 28 are replaced, foreign matter such as dust is prevented from adhering to the optical elements of the output light generating optical system 32. In the case of the first embodiment, when it becomes necessary to replace the laser element 28, the entire light source module 22 is replaced.

[0050] In the first embodiment, the laser element 28 emits blue laser light L0 with a short wavelength. Light with a short wavelength is likely to collect foreign matter such as dust in the air. However, even if the laser element 28 collects foreign matter such as dust, the collected foreign matter does not adhere to the optical elements of the output light generating optical system 32 housed in the sealed space S2.

[0051] Furthermore, in the case of the present embodiment 1, the multiple laser elements 28 are present in the space S1 in a sealed state during emission of the blue laser light L0. As a result, even if the laser light L0 having a high dust-collecting effect is emitted, foreign matter such as dust does not adhere to the laser elements 28 and the collimator lens 30 in the space S1.

[0052] Such a housing structure of the light source device 20 makes it possible to suppress deterioration of the light output of the light source device 20 due to adhesion of foreign matter such as dust.

[0053] As described above, according to the first embodiment, in the light source device of the projection type image display device, it is possible to replace the light source while suppressing adhesion of foreign matter to the optical elements of the optical system.

[0054] (Embodiment 2)

[0055] The present embodiment 2 is an improved version of the embodiment 1. Therefore, the present embodiment 2 will be described focusing on the differences. Note that the components of the present embodiment 2 that are substantially the same as those of the embodiment 1 are denoted by the same reference numerals.

[0056] FIG. 3 is a schematic configuration diagram showing a light source device according to a second embodiment of the present disclosure in a state in which the light source module and the output light generation module are separated from each other.

[0057] 3, in the second embodiment, the light source module 122 of the light source device 120 includes a housing 190 that defines a sealed space S1. A plurality of laser elements 28 are housed in the sealed space S1. The housing 190 also includes a transmission window 198 through which the laser light emitted from the laser elements 28 passes. When the housing 190 is detachably attached to the housing 92 of the output light generating module 24, the transmission window 198 of the light source module 122 faces the transmission window 96 of the output light generating module 24.

[0058] According to such a light source device 120, even when the light source module 122 is separated from the output light generating module 24, it is possible to prevent foreign matter such as dust from adhering to the laser element .

[0059] In the second embodiment, similarly to the first embodiment described above, in a light source device of a projection type image display device, the light source can be replaced while suppressing adhesion of foreign matter to optical elements of the optical system.

[0060] (Embodiment 3) The present embodiment 3 is an improved version of the embodiment 1. Therefore, the present embodiment 3 will be described focusing on the differences. Note that the same reference numerals are used to designate the components of the present embodiment 3 that are substantially the same as those of the embodiment 1.

[0061] FIG. 4 is a schematic configuration diagram showing a light source device according to embodiment 3 of the present disclosure.

[0062] As shown in FIG. 4, in the light source device 220, the output light generating optical system 232 accommodated in the sealed space S2 defined by the housing 294 of the output light generating module 224 does not include the phosphor wheel device 40. The phosphor wheel device 40 is located outside the space S2 of the housing 294. Specifically, the light source device 220 includes a light conversion module 300 including the phosphor wheel device 40 in addition to the light source module 22 and the output light generating module 224. The light conversion module 300 has a housing 302 that defines a space S3 that contains the phosphor wheel device 40. The housing 302 is detachably attached to the housing 294 of the output light generating module 224. When the housing 302 is attached to the housing 294, the space S3 is substantially sealed.

[0063] In output light generating optical system 232, lens 44 facing reflective substrate 40a of phosphor wheel device 40 is fitted into a through hole formed in housing 294 and functions as a transmission window (third transmission window). Lens 44 functioning as this transmission window allows first blue light L1 to travel from space S2 of housing 292 toward reflective substrate 40a of phosphor wheel device 40 housed in space S3 of housing 302. Also, yellow light from reflective substrate 40a can travel from space S3 to space S2. That is, in the case of the present embodiment 3, output light generating optical system 232 housed in space S1 and phosphor wheel device 40 arranged outside space S1 cooperate to generate white light Lw.

[0064] In this manner, by disposing phosphor wheel device 40 outside space S2 defined by housing 294 of output light generating module 224, output light generating module 224 does not have any components that operate by receiving power. Therefore, the possibility of output light generating module 224 failing during normal use is substantially zero, and the life span is extended. That is, in light source device 220 of the third embodiment, the components that require replacement due to a failure or a life span are light source module 22 and light conversion module 300.

[0065] In the third embodiment, similarly to the first embodiment, in the light source device of the projection type image display device, the light source can be replaced while suppressing adhesion of foreign matter to optical elements of the optical system. In addition, the phosphor wheel device can be replaced while suppressing adhesion of foreign matter to optical elements of other optical systems.

[0066] Although the present disclosure has been described above with reference to the above-mentioned first to third embodiments, the embodiments of the present disclosure are not limited to the above-mentioned embodiments.

[0067] For example, in the case of the above-mentioned first embodiment, the light source device 20 includes one light source that emits blue laser light L0. However, the embodiment of the present disclosure is not limited thereto. For example, the light source device may have a light source that emits red light, a light source that emits green light, and a light source that emits blue light. In this case, at least one first transmission window through which the light of each color emitted from each light source passes is provided in the first housing (the housing of the output light generation module). That is, each of the lights of each color may pass through the corresponding first transmission window, or each of the lights of each color may pass through one first transmission window. In this case, the output light generation optical system housed in the sealed space defined by the first housing generates white light by combining the lights of each color.

[0068] The first housing may be composed of a single component, or may be composed of a part of a housing (so-called main body) that houses all the components of the projection type image display device. The first housing may be anything that can define an enclosed space.

[0069] As described above, the above-mentioned embodiment has been described as an example of the technology in the present disclosure. For this purpose, drawings and detailed description are provided. Therefore, among the components described in the drawings and detailed description, not only components essential for solving the problem but also components that are not essential for solving the problem in order to illustrate the above-mentioned technology may be included. Therefore, the fact that these non-essential components are described in the drawings or detailed description should not be used to immediately determine that these non-essential components are essential.

[0070] Furthermore, since the above-described embodiments are intended to illustrate the technology in the present disclosure, various modifications, substitutions, additions, omissions, and the like can be made within the scope of the claims or their equivalents. [Industrial Applicability]

[0071] The present disclosure is applicable to a light source device in which the light source is replaceable. [Explanation of symbols]

[0072] 20 Light source device 28 Light source (laser element) 32 Output light generation optical system 52 Second transmission window (condenser lens) 92 First Case 96 First transparent window L0 light (laser light) Lw output light (white light) S2 Closed space

Claims

1. A first housing having a first transmission window and a second transmission window; a light source disposed outside the first housing and configured to emit light so as to pass through the first transmission window and enter the first housing; an output light generating optical system that is contained in the first housing, generates a predetermined output light from the light that has passed through the first transmission window, and transmits the output light through the second transmission window to emit it to the outside of the first housing; the output light generating optics including a phosphor wheel device including a reflective substrate; Light source device.

2. a second housing having the light source; The light source device according to claim 1 , wherein the second housing is attached to the first housing such that the light source faces the first transmission window.

3. The light source device described in claim 1, wherein the phosphor wheel includes a phosphor that converts blue light into yellow light.

4. 4. The light source device according to claim 3, wherein the output light generating optical system splits the blue light from the light source into a first blue light and a second blue light, guides the first blue light toward the reflective substrate, and generates white light as the output light by combining the yellow light reflected from the reflective substrate and the second blue light.

5. The light source device according to claim 2 , wherein the second housing is detachably attached to the first housing.

6. The light source device according to claim 4 , wherein the output light generating optical system includes a mirror onto which the second blue light is incident.

7. a condenser lens disposed at a position where the first blue light is incident; The light source device according to claim 4 , wherein the first blue light condensed by the condenser lens is incident on the phosphor wheel.

8. A light source device as described in claim 1, comprising a first cooling device on the outer surface of the first housing for cooling the phosphor wheel.

9. A light source device as described in claim 2, further comprising a second cooling device on the outer surface of the second housing for cooling the light source.

10. A light source device according to any one of claims 1 to 9, an image forming module that converts output light of the light source device into image light; a projection optical system that projects the image light from the image forming module.

11. A third housing having the image forming module and a third transparent window, 11. The projection type image display device according to claim 10, wherein the light emitted from the second transmission window is incident on the third transmission window.

12. A projection type image display device as described in Claim 10, wherein the third housing is located outside the second housing.

Images