Optical module and projector

Abstract

Optical module and projector. Provided are an optical module and a projector capable of suppressing a decrease in reliability caused by multiple reflection of light. The optical module of the present invention includes: a first light source including a light emitting element that emits excitation light and a wavelength conversion element that converts the excitation light into light of a different wavelength band; a light filter that cuts off the excitation light included in light incident from the first light source; and a polarizing plate into which light that has passed through the light filter is incident, at least one of the light filter and the polarizing plate being disposed obliquely to a state perpendicular to an optical axis of light emitted from the first light source.

Description

Technical Field

[0001] This invention relates to optical modules and projectors. Background Technology

[0002] Previously, it was known that a projector had a light source that emitted light, a light modulation device that modulates the light emitted from the light source according to image information to generate image light, and a projection optical system that amplifies and projects the image light emitted from the light modulation device onto a projection surface such as a screen.

[0003] Patent Document 1 discloses a projector comprising: an LED light source that emits light; a block-shaped light guide element that emits light from the LED light source from an emitting end to achieve uniform brightness; a condenser lens that images the light source image of the light emitted from the light guide element at the entrance pupil position of the projection lens; a light modulation element that generates image light; and a projection lens.

[0004] Patent Document 1: Japanese Patent Application Publication No. 2000-180962

[0005] For example, in the projectors described above, a light source that generates green light by exciting a phosphor with short-wavelength excitation light is sometimes used. In such cases, it is considered to install a filter that cuts off short-wavelength light. However, short-wavelength light that is not completely blocked by the filter can cause multiple reflections between the filter and subsequent optical components, potentially reducing the reliability of the optical elements. Summary of the Invention

[0006] To address the aforementioned issues, one aspect of the optical module of the present invention comprises: a first light source including a light-emitting element that emits excitation light and a wavelength conversion element that converts the excitation light into light of different wavelength bands; a filter that cuts off the excitation light contained in light incident from the first light source; and a polarizing plate onto which light passing through the filter is incident, wherein at least one of the filter and the polarizing plate is disposed at an angle perpendicular to the optical axis, the optical axis being the optical axis of light emitted from the first light source.

[0007] One aspect of the present invention provides a projector comprising a first image forming module, the first image forming module including: an optical module as described above; and a first light modulation element that modulates light incident from the polarizer of the optical module based on image information. Attached Figure Description

[0008] Figure 1 This is a top view showing the schematic structure of the projector according to an embodiment.

[0009] Figure 2 This is a diagram showing the configuration of the filter and polarizer in the comparative example.

[0010] Figure 3 This is a diagram illustrating the configuration of the filter and polarizer in the embodiment.

[0011] Figure 4A This is a diagram showing the configuration of the filter and polarizer as observed along the optical axis.

[0012] Figure 4B This is a top view obtained by observing the configuration structure of the filter and polarizer from the +D3 side.

[0013] Figure 5 This is a diagram illustrating the action of the transmitted components in the green optical module.

[0014] Figure 6 This is a 3D view of the first light guide element.

[0015] Figure 7 This is a top view showing the peripheral structure of the light guide element.

[0016] Figure 8 It is along Figure 7 A sectional view along line VII-VII.

[0017] Figure 9 This is a schematic diagram used to illustrate the behavior of leaked light.

[0018] Figure 10 This is a diagram showing the configuration structure of the filter and polarizer involved in the modified example.

[0019] Label Explanation

[0020] 10: Plate material; 10a: Reflective surface; 11: Component 1; 11a: Component 1; 12: Component 2; 12a: Component 2; 13: Component 3; 13a: Component 3; 14: Component 4; 14a: Component 4; 41a: Component 4; 41b: Component 4; 41L: Light guide path; 41: Component 1 (light guide element); 50: Adhesive; 100G: Component 1 (image forming module); 100B: Component 2 (image forming module); 100R: Component 3 (image forming module); 101: Green optical module (optical module); 124: Wavelength conversion element; 150: Holding Components; 151: Frame; 151K: Opening; 152: Fixing component; 164: Filter; 165: Polarizing plate; 181: First optical modulation element; 182: Second optical modulation element; 183: Third optical modulation element; 200: Optical combining element; 250: Projection optical system; 301: Projector; 401: First light source; 402: Second light source; 403: Third light source; AX1: Optical axis; BG: Excitation light; IB: Blue image light; IG: Green image light; IR: Red image light; LB: Blue light; LG: Green light (first light); LR: Red light; M: Middle part. Detailed Implementation

[0021] Hereinafter, embodiments of the present invention will be described using the accompanying drawings.

[0022] The projector in this embodiment is an example of a liquid crystal projector that uses a liquid crystal panel as a light modulation device.

[0023] In the following figures, the scales of the dimensions are sometimes different depending on the structural elements so as to facilitate observation of the various structural elements.

[0024] Figure 1 This is a top view showing the schematic structure of the projector according to an embodiment.

[0025] like Figure 1 As shown, the projector 301 is an image display device equipped with three liquid crystal panels as light modulation devices, and is a so-called three-panel projector. The projector 301 includes a first image forming module 100G, a second image forming module 100B, a third image forming module 100R, a light combining element 200, and a projection optical system 250.

[0026] The first image forming module 100G includes a green optical module (optical module) 101 and a green light modulation device 104. The second image forming module 100B includes a blue optical module 102 and a blue light modulation device 105. The third image forming module 100R includes a red optical module 103 and a red light modulation device 106.

[0027] In the following description, the direction parallel to the optical axis of the blue light LB emitted from the blue optical module 102 is defined as the D1 direction. One side of the D1 direction is defined as the -D1 side, and the side of the D1 direction opposite to the -D1 side is defined as the +D1 side. The direction perpendicular to the D1 direction within the plane containing the optical axis of the blue light LB is defined as the D2 direction. One side of the D2 direction is defined as the -D2 side, and the side of the D2 direction opposite to the -D2 side is defined as the +D2 side. The direction perpendicular to both the D1 and D2 directions is defined as the D3 direction. The blue light LB emitted from the blue optical module 102 travels along the D1 direction toward the +D1 side.

[0028] First, the first image forming module 100G will be described. The green optical module 101 of the first image forming module 100G includes a first light source 401, a first light guide element 41, a first parallelizing element 161, a filter 164, and a polarizer 165. In the green optical module 101, the first light source 401, the first light guide element 41, the first parallelizing element 161, the filter 164, and the polarizer 165 are arranged along the optical axis AX1 of the first light source 401. Furthermore, the optical axis AX1 of the first light source 401 is the axis along the principal ray in the light emitted radially from the first light source 401, and is an axis extending parallel to the D2 direction.

[0029] The first light source 401 includes a first substrate 111, a first light-emitting element 121 mounted on the first substrate 111, and a wavelength conversion element 124 disposed on the light-emitting surface 121a of the first light-emitting element 121. The first substrate 111 is a plate parallel to a surface including the D1 direction and the D3 direction.

[0030] The first light-emitting element 121 is an LED that emits excitation light BG from the light-emitting surface 121a to excite the wavelength conversion element 124. The excitation light BG is, for example, light in the 400nm to 450nm wavelength range, with a peak wavelength at 420nm. The excitation light BG contains a relatively large number of shorter wavelengths compared to the blue light LB described later. The excitation light BG has the shortest wavelength among the colored lights used in the projector 301, and therefore has high energy.

[0031] Wavelength conversion element 124 is a green phosphor that converts excitation light BG into green light LG (light of different wavelengths) in the green wavelength range of 500nm to 560nm. In the first light source 401, a portion of the excitation light BG is not converted into green light LG at the wavelength conversion element 124, but passes through the wavelength conversion element 124. Therefore, the first light source 401 emits light containing green light LG and excitation light BG toward the first light guide element 41.

[0032] The first light guide element 41 is disposed on the light emitting side of the first light source 401, and is positioned closer to the first light-emitting element 121 of the first light source 401 on the +D2 side and overlaps with the first light-emitting element 121 in the D1 and D3 directions. Details about the first light guide element 41 will be described later.

[0033] The first parallelizing element 161 is disposed in the optical path of the light emitted from the first light guide element 41. The first parallelizing element 161 makes the light emitted from the first light guide element 41 parallel along the D2 direction.

[0034] As described above, the excitation light BG contained in the light emitted from the first light source 401 is the main reason for the reduction in the color of the image light in the first image forming module 100G. In contrast, the green optical module 101 of this embodiment includes a filter 164 that blocks the excitation light BG contained in the light emitted from the first light source 401. The filter 164 is disposed in the optical path of the green light LG emitted from the first parallelization element 161.

[0035] Filter 164 has the optical properties of reflecting the excitation light BG and allowing the green light LG to pass through. The excitation light BG reflected by filter 164 returns to the first light source 401 via the first light guide element 41 for re-excitation of wavelength conversion element 124. In this way, by returning the excitation light BG to the first light source 401, the conversion efficiency of wavelength conversion element 124 can be improved.

[0036] Green light LG, having passed through filter 164, is incident on polarizer 165. Polarizer 165 directs the predefined polarized light in the green light LG along the D2 direction toward the +D2 side. Polarizer 165 is a reflective polarizer.

[0037] On the other hand, it is difficult to completely cut off the excitation light BG in the filter 164, resulting in about 1% of the excitation light BG passing through the filter 164. The transmitted component BG1 of the excitation light BG that has passed through the filter 164 is incident on the polarizer 165, and at least a portion of the transmitted component BG1 is reflected by the polarizer 165.

[0038] The transmitted component BG1, after being reflected by polarizer 165, re-enters filter 164. Filter 164 has the characteristic of reflecting the excitation light BG, therefore the transmitted component BG1 is reflected again by filter 164 and enters polarizer 165. It is assumed that because polarizer 165 reflects at least a portion of the re-entered transmitted component BG1 towards filter 164, multiple reflections of the transmitted component BG1 occur between filter 164 and polarizer 165.

[0039] Here, with reference to the structure of the comparative example, the relationship between the arrangement of the filter 164 and the polarizer 165 and multiple reflections will be explained. Figure 2This diagram illustrates the configuration of the filter 164 and polarizer 165 in the comparative example. Furthermore, the green optical module 101 of this embodiment differs from the comparative example in the configuration of the filter 164 and polarizer 165 relative to the optical axis AX1; otherwise, the structures are the same.

[0040] like Figure 2 As shown, in the comparative example, the filter 164 and the polarizer 165 are configured to be perpendicular to the optical axis AX1 of the first light source 401.

[0041] like Figure 2 As shown, the transmitted component BG1, parallel to the optical axis AX1, is incident perpendicularly to the polarizer 165, thus easily causing multiple reflections between the filter 164 and the polarizer 165. The excitation light BG is parallelized by the first parallelizing element 161 and incident on the filter 164; therefore, the transmitted component BG1 of the excitation light BG passing through the filter 164 contains a significant amount of the component parallel to the optical axis AX1. Therefore, as in the comparative example structure, when the filter 164 and the polarizer 165 are respectively arranged perpendicularly to the optical axis AX1, more multiple reflections of the transmitted component BG1 between the filter 164 and the polarizer 165 are generated, potentially promoting the degradation of the polarizer 165 and reducing reliability.

[0042] Figure 3 This is a diagram showing the configuration structure of the filter 164 and polarizer 165 in the green optical module 101 of this embodiment. Figure 4A This is a diagram showing the configuration of the filter 164 and polarizer 165 as viewed from the -D2 side toward the +D2 side along the optical axis AX1. Figure 4B This is a top view obtained by observing the configuration structure of filter 164 and polarizer 165 from the +D3 side.

[0043] like Figure 3 As shown, the filter 164 and the polarizer 165 are respectively tilted from a state perpendicular to the optical axis AX1 of the first light source 401.

[0044] The green optical module 101 of this embodiment also includes a holding member 150, which is disposed between the filter 164 and the polarizer 165 to hold the filter 164 and the polarizer 165.

[0045] The retaining component 150 holds the filter 164 and the polarizer 165 in a non-parallel state. For example... Figure 4AAs shown, the retaining member 150 includes a frame-like body 151 and a fixing member 152. The frame-like body 151 is a four-sided frame member with an opening 151K. The frame-like body 151 is fixed to a housing (not shown) within the projector 301 via a mounting portion 151a provided at the end on the +D3 side. The frame-like body 151 is configured to be perpendicular to the optical axis AX1, specifically, configured to be parallel to a surface including the D1 and D3 directions.

[0046] The fixing component 152 is disposed around the opening 151K of the frame 151, and fixes the periphery of the filter 164 and the polarizer 165 to the frame 151. The fixing component 152 is made of elastic components such as double-sided tape or adhesive.

[0047] The fixing component 152 includes a first fixing part 152a that fixes the filter 164 to the -D2 side of the frame 151 and a second fixing part 152b that fixes the polarizer 165 to the +D2 side of the frame 151.

[0048] like Figure 4A As shown, the first fixing part 152a is provided at four locations: near the two corners on the +D3 side of the opening 151K and near the two corners on the -D3 side of the opening 151K. The second fixing part 152b is similarly provided at four locations: near the two corners on the +D3 side of the opening 151K and near the two corners on the -D3 side of the opening 151K. That is, as... Figure 4B As shown, the first fixing part 152a and the second fixing part 152b are respectively provided at the same position on both sides of the frame 151. In addition, the positions of the first fixing part 152a and the second fixing part 152b can be arranged as long as they do not overlap with the opening 151K, and they can also be arranged at different positions when viewed from above.

[0049] The planar dimensions of the filter 164 and polarizer 165 are set to be larger than the beam width of the light incident from the first light source 401. Therefore, the light from the first light source 401 hardly incidents on the periphery of the filter 164 and polarizer 165, which is fixed to the frame 151 via the fixing member 152.

[0050] Furthermore, the light incident on the filter 164 and polarizer 165 passes through the frame 151 via the opening 151K. Additionally, as described above, the fixing member 152 is provided around the opening 151K. Therefore, the retaining member 150 holds the filter 164 and polarizer 165 in a manner that does not obstruct the light incident on them.

[0051] The filter 164 is tilted towards the -D2 side from a state perpendicular to the optical axis AX1 in a plane including the D2 and D3 directions. Specifically, the filter 164 is tilted relative to the optical axis AX1 such that the end on the +D3 side is closer to the -D2 side than the end on the -D3 side.

[0052] The polarizer 165 is tilted towards the +D2 side from a state perpendicular to the optical axis AX1 in a plane including the D2 and D3 directions. Specifically, the polarizer 165 is tilted relative to the optical axis AX1 such that the end on the +D3 side is closer to the +D2 side than the end on the -D3 side.

[0053] exist Figure 3 In this process, the angle between the filter 164 and the frame 151 perpendicular to the optical axis AX1 is set as θ1, and the angle between the polarizer 165 and the frame 151 perpendicular to the optical axis AX1 is set as θ2.

[0054] The filter 164 is tilted at an angle θ1 from a position perpendicular to the optical axis AX1, and the polarizer 165 is tilted at an angle θ2 from a position perpendicular to the optical axis AX1 to the opposite side of the filter 164. Furthermore, it is preferable that angles θ1 and θ2 are set to the ranges of 0° < θ1 ≤ 5° and 0° < θ2 ≤ 5°, respectively. More preferably, they are set to the ranges of θ1 ≥ 0.1° and θ2 ≥ 0.1°, respectively; and even more preferably, they are set to the ranges of θ1 ≥ 0.2° and θ2 ≥ 0.2°, respectively.

[0055] According to this structure, the filter 164 and the polarizer 165 are configured at an appropriate angle relative to the optical axis AX1. Therefore, as will be described later, the transmitted component BG1 of the excitation light BG, which is reflected between the filter 164 and the polarizer 165, can be well emitted to the outside of the filter 164 and the polarizer 165.

[0056] Furthermore, even though both the filter 164 and the polarizer 165 are tilted from a vertical position relative to the optical axis AX1, the filter 164 and the polarizer 165 are parallel to each other, provided that the angles θ1 and θ2 are satisfied.

[0057] Thus, when the filter 164 and the polarizer 165 are parallel, the light transmitted from the component BG1, incident from a direction perpendicular to the filter 164, is sometimes reflected multiple times between the filter 164 and the polarizer 165, similar to the structure in the comparative example.

[0058] Therefore, in this embodiment, the holding member 150 sets both angles θ1 and θ2 to 0.6°, and keeps the filter 164 and the polarizer 165 non-parallel to each other.

[0059] The tilt of the filter 164 relative to the optical axis AX1 is adjusted by the thickness of the first fixing part 152a. The aforementioned angle θ1 can be set by making the thickness of the first fixing part 152a on the +D3 side of the opening 151K greater than the thickness of the first fixing part 152a on the -D3 side of the opening 151K.

[0060] Furthermore, the tilt of the polarizing plate 165 relative to the optical axis AX1 is adjusted by the thickness of the second fixing part 152b. The aforementioned angle θ2 can be set by making the thickness of the second fixing part 152b on the +D3 side of the opening 151K greater than the thickness of the second fixing part 152b on the -D3 side of the opening 151K.

[0061] Figure 5 This is a diagram illustrating the operation of the transmittance component BG1 in the green optical module 101 of this embodiment. Figure 5 In order to make it easier to observe the accompanying drawings, only the filter 164 and the polarizer 165 are shown, and the holding component 150 is omitted.

[0062] like Figure 5 As shown, in the green optical module 101, the filter 164 and the polarizer 165 are tilted from a state perpendicular to the optical axis AX1 and are not parallel to each other. Specifically, the filter 164 and the polarizer 165 are configured such that, in a plane including the D2 and D3 directions, the gap between the filter 164 and the polarizer 165 in the D2 direction increases as they move from the -D3 side to the +D3 side.

[0063] As mentioned above, the short-wavelength excitation light BG is high-energy light. Therefore, when the transmitted component BG1, which is part of the excitation light BG, produces multiple reflections between the filter 164 and the polarizer 165, it becomes the main reason for the degradation of the polarizer 165 and the reduction of its reliability.

[0064] In contrast, in the green optical module 101 of this embodiment, the first transmitted component BG11 of the transmitted component BG1 incident on the +D3 side of the filter 164 is reflected by the polarizer 165 and the filter 164, and thus emitted from between the filter 164 and the polarizer 165 in the D3 direction perpendicular to the optical axis AX1. Then, the first transmitted component BG11 travels as stray light in the projector 301 and is absorbed by a light-absorbing component (not shown).

[0065] In this embodiment, as described above, the filter 164 and the polarizer 165 are not parallel to each other. Therefore, even if the transmittant BG1 is incident on the filter 164 at any incident angle, it is difficult for multiple reflections to occur between the filter 164 and the polarizer 165.

[0066] Thus, according to the green optical module 101 of this embodiment, the first transmittance component BG11 that passes through the filter 164 is not subject to multiple reflections between the filter 164 and the polarizer 165, thereby suppressing the degradation of the polarizer 165 due to multiple reflections of the short-wavelength first transmittance component BG11.

[0067] Furthermore, the second transmitted component BG12, which is incident on the -D3 side of the filter 164, changes direction approximately parallel to the D3 direction whenever it is reflected between the polarizer 165 and the filter 164. Then, the second transmitted component BG12 exits from between the filter 164 and the polarizer 165 towards the +D3 side in the D3 direction perpendicular to the optical axis AX1, travels as stray light within the projector 301, and is absorbed by a light-absorbing component (not shown). Therefore, the second transmitted component BG12 does not undergo multiple reflections between the filter 164 and the polarizer 165, thus suppressing the degradation of the polarizer 165 caused by multiple reflections.

[0068] Thus, according to the green optical module 101 of this embodiment, the filter 164 and the polarizer 165 are tilted from a state perpendicular to the optical axis AX1. Therefore, between the filter 164 and the polarizer 165, whenever the transmitted component BG1 of the excitation light BG is reflected, its direction changes in the D3 direction perpendicular to the optical axis AX1, allowing the transmitted component BG1 of the excitation light BG to exit to the outside between the filter 164 and the polarizer 165. This provides a highly reliable optical module that suppresses the decrease in reliability associated with the degradation of the polarizer 165 caused by the short-wavelength excitation light BG by preventing multiple reflections of the transmitted component BG1 of the excitation light BG between the filter 164 and the polarizer 165.

[0069] In the green optical module 101 of this embodiment, green light LG that has passed through the filter 164 and the polarizer 165 is incident on the green light modulation device 104.

[0070] The green light modulation device 104 includes a first light modulation element 181 and a first emission side polarization element 175.

[0071] The first light modulation element 181 modulates the green light LG incident from the polarizer 165 of the green optical module 101. The first light modulation element 181 is, for example, a transmissive liquid crystal panel. The liquid crystal panel constituting the first light modulation element 181 modulates the green light LG based on green image information, thereby generating green image light IG. The first light modulation element 181 emits the generated green image light IG along the D2 direction toward the +D2 side.

[0072] The first emission-side polarizing element 175 is positioned closer to the +D2 side than the first optical modulation element 181. The first emission-side polarizing element 175 emits a predetermined polarized light from the green image light IG emitted from the first optical modulation element 181 along the D2 direction toward the +D2 side. The first emission-side polarizing element 175 is, for example, a reflective polarizer or an absorptive polarizer.

[0073] Next, the structure of the first light guide element 41 will be described.

[0074] Figure 6 This is a three-dimensional view of the first light guide element 41. (See diagram below.) Figure 6 As shown, the first light guide element 41 defines a light guide path for guiding the green light LG emitted from the first light-emitting element 121, and propagates the green light LG to the first light modulation element 181. The first light guide element 41 is composed of multiple plates 10 and an adhesive 50, and the multiple plates 10 are formed of transparent material. The multiple plates 10 include a first component 11, a second component 12, a third component 13, and a fourth component 14.

[0075] Component 11 and component 13 are a pair of rectangular plates. Component 11 has a first reflective surface 11a on one side of its plane. Component 13 has a third reflective surface 13a on one side of its plane. Component 11 and component 13 are plates of the same shape.

[0076] The second component 12 and the fourth component 14 are a pair of trapezoidal plates. The second component 12 has a second reflective surface 12a on one of its planes. The fourth component 14 has a fourth reflective surface 14a on one of its planes. The second component 12 and the fourth component 14 are plates of the same shape. Hereinafter, without specifically distinguishing between the first reflective surface 11a, the second reflective surface 12a, the third reflective surface 13a, and the fourth reflective surface 14a, they will sometimes be collectively referred to as reflective surface 10a. Reflective surface 10a constitutes a light guide path 41L that guides the green light LG toward the inner side of the first light guide element 41.

[0077] Thus, the first light guide element 41 uses four sheets of sheet metal, making manufacturing easier. Furthermore, the first light guide element 41 is constructed using rectangular sheet metal, reducing the number of sheet metal processing steps. Moreover, since the sheet metal has a simple shape, assembly is easier.

[0078] Furthermore, the plurality of plates 10 constituting the first light guide element 41 can also be composed of two plates. More specifically, the first component 11 and the second component 12 can also be integrally formed. Similarly, the third component 13 and the fourth component 14 can also be integrally formed.

[0079] The first reflective surface 11a of the first component 11 and the third reflective surface 13a of the third component 13 are arranged opposite each other. The second reflective surface 12a of the second component 12 and the fourth reflective surface 14a of the fourth component 14 are arranged opposite each other. The second component 12 and the fourth component 14 are arranged with the upper bottom on the -D2 side and the lower bottom on the +D2 side.

[0080] One side of the inclined portion of the second component 12 and the fourth component 14, which are trapezoidal in shape, is connected to the first reflective surface 11a of the first component 11. The other side of the inclined portion of the second component 12 and the fourth component 14 is connected to the third reflective surface 13a of the third component 13. The plurality of plates 10 are bonded together by the adhesive 50 described later. Thus, the shape of the first light guide element 41 is formed by the plurality of plates 10.

[0081] The first component 11 has a first incident end face 11e at its end on the -D2 side. The second component 12 has a second incident end face 12e at its end on the -D2 side. The third component 13 has a third incident end face 13e at its end on the -D2 side. The fourth component 14 has a fourth incident end face 14e at its end on the -D2 side. A portion of the first incident end face 11e, a portion of the second incident end face 12e, a portion of the third incident end face 13e, and the fourth incident end face 14e form an incident opening 45. The incident opening 45 forms the incident end 41a of the light guide path 41L.

[0082] The first component 11 has a first emission end face 11f at its end on the +D2 side. The second component 12 has a second emission end face 12f at its end on the +D2 side. The third component 13 has a third emission end face 13f at its end on the +D2 side. The fourth component 14 has a fourth emission end face 14f at its end on the +D2 side. The first emission end face 11f, the second emission end face 12f, the third emission end face 13f, and the fourth emission end face 14f form an emission opening 46. The emission opening 46 forms the emission end 41b of the light guide path 41L.

[0083] The incident opening 45 extends parallel to the surface encompassing directions D1 and D3. The shape of the incident opening 45 when viewed from direction D2 is the same as the shape of the emitting surface of the first light-emitting element 121 when viewed from the same direction; it is rectangular. The size of the incident opening 45 may also be equal to the size of the emitting surface of the first light-emitting element 121, but it is preferably moderately larger.

[0084] The emission opening 46 extends parallel to the surface encompassing directions D1 and D3. The emission opening 46 is larger than the incident opening 45. The shape of the emission opening 46 when viewed from direction D2 is rectangular. The size of the emission end 41b is equal to the size of the first optical modulation element 181.

[0085] According to this structure, the beam width can be increased during the propagation of green light LG incident from the incident opening 45 within the light guide path. This allows for the generation of green light LG with a uniform illuminance distribution that efficiently illuminates the entire first light modulation element 181.

[0086] Figure 7 This is a top view showing the peripheral structure of the light guide element. (Example) Figure 7 As shown, the light guide path 41L of the first light guide element 41 has an incident end 41a and an emitted end 41b. The incident end 41a is located on the -D2 side in the D2 direction. The emitted end 41b is located on the +D2 side in the D2 direction.

[0087] Here, the first incident end face 11e and the third incident end face 13e are parallel to the surface including the D1 direction and the D3 direction. In the case of directly bonding ordinary sheet metal, such as... Figure 7 As shown by the dashed lines, the corners of the first incident end face 11e and the third incident end face 13e in the first component 11 and the third component 13 protrude towards the -D2 side. In this embodiment, the corners of the first incident end face 11e and the third incident end face 13e are cut off in a manner parallel to the plane including the D1 direction and the D3 direction. In addition, the second incident end face 12e and the fourth incident end face 14e are also similarly parallel to the plane including the D1 direction and the D3 direction.

[0088] According to this structure, the gap between the incident opening 45 and the first light source 401 in the D2 direction can be reduced. Therefore, the incident opening 45 and the first light source 401 can be arranged close together in the D2 direction. As a result, the amount of leakage light LL generated during the period from the first light source 401 toward the incident opening 45 of the first light guide element 41 can be suppressed.

[0089] Furthermore, in this embodiment, the first ejection end face 11f and the third ejection end face 13f are parallel to the plane including the D1 and D3 directions. Similarly, the second ejection end face 12f and the fourth ejection end face 14f are also parallel to the plane including the D1 and D3 directions. The corners of the first ejection end face 11f and the third ejection end face 13f can also be cut off in a manner parallel to the plane including the D1 and D3 directions.

[0090] According to this structure, the gap between the emission opening 46 and the first optical modulation element 181 can be reduced. Therefore, the emission opening 46 and the first optical modulation element 181 can be arranged close together. Therefore, the amount of leakage light LL generated during the period from the emission opening 46 of the first light guide element 41 toward the first optical modulation element 181 can be suppressed.

[0091] Green light LG emitted from the first light source 401 enters the light guide path 41L of the first light guide element 41 from the incident end 41a. In the first light guide element 41, the space surrounded by the incident opening 45, the exit opening 46, and the reflecting surface 10a becomes the light guide path 41L for propagating the green light LG. Thus, the green light LG incident on the first light guide element 41 propagates from the -D2 side to the +D2 side within the light guide path 41L.

[0092] A portion of the green light LG incident on the first light guide element 41 propagates directly from the incident end 41a to the exit end 41b along an angle smaller than the inclination of the hypotenuse of the trapezoid in the second component 12 and the fourth component 14, without ever incident on the reflecting surface 10a. The remaining portion of the green light LG incident on the first light guide element 41, forming an angle greater than the aforementioned angle, is incident on the reflecting surface 10a more than once from the incident end 41a, is reflected by the reflecting surface 10a, and reaches the exit end 41b. The paths of the green light LG within the region surrounded by the incident end 41a, the exit end 41b, and the reflecting surface 10a vary depending on the incident angle towards the incident end 41a, resulting in multiple paths with different numbers of reflections reaching the reflecting surface 10a. Therefore, the illuminance distribution of the green light LG propagating in the region surrounded by the incident end 41a, the exit end 41b, and the reflecting surface 10a is homogenized within the plane including the D1 and D3 directions. That is, the first light guide element 41 homogenizes the illuminance distribution of the incident green light LG in the plane including the D1 and D3 directions. The green light LG with homogenized illuminance distribution is emitted from the emission end 41b towards the +D2 side.

[0093] Next, the adhesive 50 for bonding the multiple plates 10 will be described. The adhesive 50 bonds the multiple plates 10 to the outside of the light guide path, forming a first light guide element 41 having a light guide path 41L. The adhesive 50 is arranged along a portion of the inclined side of the trapezoid in the second component 12 and the fourth component 14. The adhesive 50 is positioned approximately at the middle portion M of the light guide path 41L closer to the emission end 41b than the middle portion M in the length direction (D2 direction) of the light guide path 41L. Here, the middle portion M of the light guide path 41L refers to a position located equidistant from the incident end 41a and the emission end 41b in the D2 direction.

[0094] In this embodiment, the adhesive 50 is positioned at approximately 3 / 4 of the distance from the injection end 41a toward the injection end 41b. Alternatively, a portion of the adhesive 50 may be positioned closer to the injection end 41a than the middle portion M.

[0095] Regarding the contact area of ​​the adhesive 50 with respect to the plurality of plates 10, the contact area on the emitting end 41b side relative to the middle part M of the light guide path is larger than the contact area on the incident end 41a side relative to the middle part M.

[0096] Figure 8 It is along Figure 7 A sectional view along line VII-VII. Figure 8 For ease of observation, we will focus only on the case where adhesive 50 bonds the first component 11 and the second component 12. For example... Figure 7 , Figure 8 As shown, the adhesive 50 is located outside the light guide path defined by the first light guide element 41.

[0097] Regarding the first component 11 and the second component 12, one side of the inclined portion of the second component 12 abuts against a portion of the first reflective surface 11a of the first component 11. Adhesive 50 bonds the outer side of the light guide path 41L in the first reflective surface 11a and the outer surface 12b of the second component 12 located on the opposite side of the second reflective surface 12a. Thus, regarding the contact area of ​​adhesive 50 with respect to the first component 11 and the second component 12, the contact area on the emission end 41b side relative to the middle portion M of the light guide path 41L is larger than the contact area on the incident end 41a side relative to the middle portion M. In this way, the first component 11 and the second component 12 are bonded via adhesive 50. Similarly, the second component 12 and the third component 13, the third component 13 and the fourth component 14, and the fourth component 14 and the first component 11 are respectively bonded via adhesive 50.

[0098] Furthermore, the adhesive 50 may not be integrally formed along a portion of the hypotenuse of the trapezoid in the second component 12 and the fourth component 14, or it may be provided as a series of interrupted states. The contact area in this embodiment is not limited to the case of continuous contact, but includes the total area of ​​intermittent contact.

[0099] The adhesive 50 can be any type, including UV-curing, natural-curing, and heat-curing types. The adhesive 50 can be modified as long as it can bond multiple plates 10 to form the shape of the first light guide element 41.

[0100] In the first light guide element 41 configured in this way, even when the incident opening 45 is close to the first light source 401, there is a case where a portion of the green light LG leaks to the outside of the guide light path 41L and becomes leakage light LL. The leakage light LL is generated during the period from the first light source 401 toward the incident opening 45 of the first light guide element 41 and leaks to the outside of the guide light path 41L.

[0101] Here, the behavior of the leaking light LL will be explained. Figure 9 This is a schematic diagram used to illustrate the behavior of leaky light (LL). For example... Figure 9As shown, the leaked light LL is light emitted from the first light source 401 along an angle larger than the cone angle of the trapezoid formed by the second component 12 and the fourth component 14. The leaked light LL contains various angular components, but the leaked light LL emitted along an angle slightly larger than the cone angle of the trapezoid formed by the second component 12 and the fourth component 14 is more likely to be incident on the side of the incident end 41a side of the first light guide element 41.

[0102] On the other hand, in order for the leaked light LL to reach the side of the emission end 41b in the first light guide element 41, the leaked light LL emitted in a direction that forms an angle equal to the cone angle of the trapezoid in the second component 12 and the fourth component 14 needs to travel along the outer surface of the first light guide element 41 from the incident end 41a side to the emission end 41b side. In this way, the amount of light in the leaked light LL reaching the emission end 41b side is sufficiently less than the amount of light incident on the incident end 41a side.

[0103] Therefore, when the adhesive 50 is disposed on the incident end 41a side, the adhesive 50 is prone to deterioration due to the increased irradiation amount of the leaked light LL. In particular, the green light LG of this embodiment contains short-wavelength and high-energy excitation components as described above, thus easily causing deterioration of the adhesive 50.

[0104] In contrast, in the first light guide element 41 of this embodiment, the adhesive 50 is positioned closer to the emission end 41b than the incident end 41a side. Therefore, the leaked light LL leaking from the incident opening 45 of the first light guide element 41 to the outside is less likely to come into contact with the adhesive 50, thus suppressing the deterioration of the adhesive 50. As a result, the reduction in the bonding strength of the adhesive 50 used to bond multiple plates 10 can be suppressed.

[0105] Thus, the first light guide element 41 of this embodiment includes: a plurality of plates 10 having an incident end 41a and an emitting end 41b, dividing a light guide path for guiding light; and an adhesive 50 that bonds the plurality of plates 10 to the outside of the light guide path 41L. The plurality of plates 10 include: a first component 11 having a first reflective surface 11a; and a second component 12 having a second reflective surface 12a. Regarding the contact area of ​​the adhesive 50 with respect to the first component 11 and the second component 12, the contact area on the emitting end 41b side relative to the middle portion M of the light guide path is larger than the contact area on the incident end 41a side relative to the middle portion M.

[0106] According to the first light guide element 41 of this embodiment, the adhesive 50 is positioned closer to the emission end 41b than the incident end 41a side. Therefore, the leaked light LL leaking from the incident opening 45 of the first light guide element 41 to the outside is less likely to come into contact with the adhesive 50, and the deterioration of the adhesive 50 can be suppressed. As a result, the reduction in the bonding strength of the adhesive 50 used to bond multiple plates 10 can be suppressed.

[0107] In addition, compared with the case where all the multiple plates 10 are trapezoidal, the bonding surface between the adhesive 50 and the multiple plates 10 can be expanded, so it is easier to apply the adhesive 50 and easier to assemble.

[0108] The first image forming module 100G of this embodiment can provide a highly reliable optical module by suppressing the reduction in the bonding strength of the adhesive 50 that bonds the plurality of plates 10 constituting the first light guide element 41 due to the leakage light LL of the first light source 401.

[0109] Next, the second image forming module 100B will be described. The blue optical module 102 of the second image forming module 100B emits blue light LB.

[0110] The blue optical module 102 includes a second light source 402, a second light guide element 42, and a second parallelizing element 162. In the blue optical module 102, the second light source 402, the second light guide element 42, and the second parallelizing element 162 are arranged along the optical axis AX2 of the second light source 402. Furthermore, the optical axis AX2 of the second light source 402 is the axis along the principal ray in the light emitted radially from the second light source 402, and is an axis extending parallel to the D1 direction.

[0111] The second light-emitting element 122 of the second light source 402 is supported on the second substrate 112. The second substrate 112 is a plate parallel to the surface including the D2 direction and the D3 direction.

[0112] The second light-emitting element 122 is disposed on the +D1 side of the second substrate 112. The second light-emitting element 122 emits blue light LB in the blue band of the visible spectrum. The blue light LB is, for example, light in the 430nm to 500nm band, with a peak wavelength of 465nm. The second light-emitting element 122 is, for example, composed of an LED that emits blue light LB.

[0113] The second light guide element 42 is disposed in the optical path of the blue light LB emitted from the second light source 402. The structure of the second light guide element 42 is the same as that of the first light guide element 41, and it has a light guide path for guiding the blue light LB.

[0114] The second parallelizing element 162, like the first parallelizing element 161, makes the blue light LB emitted from the second light guide element 42 parallel along the D1 direction.

[0115] The blue light modulation device 105 has a second incident-side polarizing element 172, a second light modulation element 182, and a second emission-side polarizing element 176. The blue light modulation device 105 is arranged in the optical path of the blue light LB emitted from the second parallelizing element 162.

[0116] The second incident polarizing element 172 emits a specified polarized light from the blue light LB emitted from the second parallelizing element 162 along the D1 direction toward the +D1 side.

[0117] The second optical modulation element 182 modulates the blue light LB emitted from the second incident side polarization element 172. The second optical modulation element 182 generates a blue image light IB based on the blue image information. The second optical modulation element 182 emits the blue image light IB along the D1 direction toward the +D1 side.

[0118] The second emission side polarizing element 176 emits the specified polarized light from the blue image light IB emitted from the second optical modulation element 182 along the D1 direction toward the +D1 side.

[0119] In the second image forming module 100B of this embodiment, the structure of the second light guide element 42 is the same as that of the first light guide element 41. Therefore, the second image forming module 100B can suppress the deterioration of the adhesive constituting the second light guide element 42 caused by leakage light from the second light source 402.

[0120] Next, the third image forming module 100R will be described. The red optical module 103 of the third image forming module 100R emits red light LR. The red light LR emitted from the red optical module 103 travels along the D1 direction toward the -D1 side.

[0121] The red optical module 103 includes a third light source 403, a third light guide element 43, and a third parallelizing element 163. In the red optical module 103, the third light source 403, the third light guide element 43, and the third parallelizing element 163 are arranged along the optical axis AX3 of the third light source 403. Furthermore, the optical axis AX3 of the third light source 403 is the axis along the principal ray in the light emitted radially from the third light source 403, and is an axis extending parallel to the D1 direction. The optical axis AX2 of the second light source 402 coincides with the optical axis AX3 of the third light source 403.

[0122] The third light-emitting element 123 of the third light source 403 is supported on the third substrate 113. The third substrate 113 is a plate parallel to the surface including the D2 direction and the D3 direction.

[0123] The third light-emitting element 123 is disposed on the -D1 side of the third substrate 113. The light-emitting surface of the third light-emitting element 123 is the -D1 side, which is opposite to the surface disposed on the third substrate 113. The third light-emitting element 123 emits red light LR in the red band of the visible spectrum. The red band is, for example, light in the 610nm to 700nm band, with a peak wavelength of 655nm. The third light-emitting element 123, like the second light-emitting element 122, is, for example, composed of an LED that emits red light LR.

[0124] The third light guide element 43 is disposed in the optical path of the red light LR emitted from the third light source 403. The structure of the third light guide element 43 is the same as that of the first light guide element 41, and it has a light guide path for guiding the red light LR.

[0125] The third parallelizing element 163, like the first parallelizing element 161 and the second parallelizing element 162, makes the red light LR emitted from the third light guide element 43 parallel along the D1 direction.

[0126] The red light modulation device 106 has a third incident-side polarizing element 173, a third light modulation element 183, and a third emission-side polarizing element 177. The red light modulation device 106 is arranged in the optical path of the red light LR emitted from the third parallelizing element 163.

[0127] The third incident-side polarizing element 173, like the second incident-side polarizing element 172, emits a predetermined polarized light from the red light LR emitted from the third parallelizing element 163 along the D1 direction toward the -D1 side.

[0128] The third optical modulation element 183, like the first optical modulation element 181 and the second optical modulation element 182, modulates the red light LR emitted from the third incident side polarizing element 173. The third optical modulation element 183 generates red image light IR. The third optical modulation element 183 emits the red image light IR along the D1 direction toward the -D1 side.

[0129] The third emission side polarizing element 177, like the first emission side polarizing element 175 and the second emission side polarizing element 176, emits a predetermined polarized light from the red image light IR emitted from the third optical modulation element 183 along the D1 direction toward the -D1 side.

[0130] In the third image forming module 100R of this embodiment, the structure of the third light guide element 43 is the same as that of the first light guide element 41. Therefore, the third image forming module 100R can suppress the deterioration of the adhesive constituting the third light guide element 43 caused by leakage light from the third light source 403.

[0131] The light combining element 200 is disposed in the region where the optical paths of the blue image light IB, the green image light IG, and the red image light IR intersect. The light combining element 200 combines the various color image lights IG, IB, and IR emitted from the first image forming module 100G, the second image forming module 100B, and the third image forming module 100R, and emits the generated composite image light IM along the D2 direction toward the +D2 side.

[0132] The projection optical system 250 is positioned on the optical path of the composite image light IM emitted from the light combining element 200. The projection optical system 250 magnifies and displays the image projected onto the screen SCR and input to the first light modulator 181, the second light modulator 182, and the third light modulator 183 on the screen SCR.

[0133] Thus, the projector 301 of this embodiment includes: a first image forming module 100G, which includes a green optical module 101 and a first optical modulation element 181 that modulates green light LG based on image information; a second image forming module 100B, which includes a second optical modulation element 182 that modulates blue light LB based on image information; a third image forming module 100R, which includes a third optical modulation element 183 that modulates red light LR based on image information; a light combining element 200 that combines and emits green image light IG emitted from the first image forming module 100G, blue image light IB emitted from the second image forming module 100B, and red image light IR emitted from the third image forming module 100R; and a projection optical system 250 that projects the combined image light IM emitted from the light combining element 200.

[0134] The projector 301 according to this embodiment can provide a highly reliable projector by having a first image forming module 100G that suppresses the decrease in reliability caused by multiple reflections of light.

[0135] Furthermore, in this embodiment, the filter 164 and the polarizer 165 are respectively tilted from a state perpendicular to the optical axis AX1 of the first light source 401, but either the filter 164 or the polarizer 165 may also be tilted from a state perpendicular to the optical axis AX1.

[0136] Figure 10 This is a diagram showing the configuration of the filter 164 and polarizer 165 involved in the modified example. Figure 10 As shown, when either the filter 164 or the polarizer 165 is tilted, it is preferable to tilt the filter 164 from a state perpendicular to the optical axis AX1. Specifically, the polarizer 165 is configured perpendicular to the optical axis AX1, and the filter 164 is configured tilted from a state perpendicular to the optical axis AX1.

[0137] Polarizer 165 exhibits an incident angle dependence in its transmittance, which varies with the incident angle of light. Typically, polarizer 165 is designed to achieve the desired transmittance when perpendicular to the optical axis AX1. Therefore, the more the polarizer 165 is tilted away from the perpendicular position to the optical axis AX1, the lower the transmittance of green light LG in polarizer 165 becomes, potentially leading to a decrease in the contrast of the green image light IG generated by the first optical modulation element 181.

[0138] according to Figure 10 In the structure shown, the polarizer 165, which is incident angle dependent, is arranged parallel to the light incident surface 181a of the first light modulation element 181. Therefore, the green light LG that has passed through the filter 164 is efficiently incident on the polarizer 165.

[0139] exist Figure 10 In the structure shown, the filter 164 and the polarizer 165 are not parallel to each other. Therefore, the transmitted component BG1 that passes through the filter 164 changes direction in a manner close to parallel to the D3 direction whenever it is reflected between the filter 164 and the polarizer 165. It is emitted outward between the filter 164 and the polarizer 165 and travels as stray light within the projector 301, where it is absorbed by a light-absorbing component (not shown).

[0140] Therefore, according to this modified example, the following structure can be achieved: suppressing the contrast reduction of the green image light IG caused by the first optical modulation element 181, and suppressing the degradation of the polarizer 165 caused by multiple reflections of the excitation light BG, as in the above embodiment.

[0141] Furthermore, in the projector 301 described above, an example is given where the second light guide element 42 of the second image forming module 100B and the third light guide element 43 of the third image forming module 100R have the same structure as the first light guide element 41 of the green optical module 101, which is the optical module of the present invention, by bonding multiple plates with an adhesive. However, the structure of the second light guide element 42 and the third light guide element 43 is not limited to this. For example, the second light guide element 42 and the third light guide element 43 may also be composed of a light-transmitting component in the shape of a frustum pyramid.

[0142] Here, if either the second light guide element 42 or the third light guide element 43 adopts the same structure as the first light guide element 41, it is preferable to apply it to the second light guide element 42 corresponding to the blue light LB. The reason for this is that the wavelength of the blue light LB is shorter than that of the red light LR, and therefore has higher energy, which easily leads to the deterioration of the adhesive strength. Thus, by adopting the same structure as the first light guide element 41 for the light guide element that guides the easily deteriorating blue light LB, the reduction in the adhesive strength can be more effectively suppressed.

[0143] Furthermore, in the green optical module 101, the first light guide element 41 and the first parallelization element 161 can be omitted based on the in-plane illuminance distribution and parallelism of the green light LG emitted from the first light source 401. Similarly, in the second image forming module 100B, the second light guide element 42 and the second parallelization element 162 can be omitted based on the in-plane illuminance distribution and parallelism of the blue light LB, and in the third image forming module 100R, the third light guide element 43 and the third parallelization element 163 can be omitted based on the in-plane illuminance distribution and parallelism of the red light LR.

[0144] The following is a summary published in this note.

[0145] Postscript 1

[0146] An optical module comprising: a first light source including a light-emitting element that emits excitation light and a wavelength conversion element that converts the excitation light into light of different wavelength bands; a filter that cuts off the excitation light contained in light incident from the first light source; and a polarizing plate onto which light passing through the filter is incident, wherein at least one of the filter and the polarizing plate is disposed at an angle perpendicular to an optical axis, the optical axis being the optical axis of light emitted from the first light source.

[0147] According to this optical module structure, the filter and polarizer are tilted from a position perpendicular to the optical axis. Therefore, whenever the transmitted component of the excitation light between the filter and polarizer is reflected, it changes direction in a direction perpendicular to the optical axis, allowing the transmitted component of the excitation light to exit to the outside between the polarizer and the filter. This provides a highly reliable optical module that suppresses the reliability reduction associated with polarizer degradation caused by the excitation light by preventing multiple reflections of the transmitted component of the excitation light between the filter and polarizer.

[0148] Appendix 2

[0149] According to the optical module described in Appendix 1, the optical module further includes a holding member disposed between the filter and the polarizer, which holds the filter and the polarizer so that they are not parallel to each other.

[0150] According to this structure, the filter and polarizer can be held in a predetermined posture by the holding member. In addition, since the filter and polarizer are arranged in a non-parallel manner, even if the transmitted component of the excitation light is incident on the filter at an arbitrary angle of incidence, it is difficult to be reflected multiple times between the filter and polarizer.

[0151] Appendix 3

[0152] According to the optical module described in Appendix 2, the holding member comprises: a frame having an opening; and a fixing member disposed around the opening for fixing the filter and the polarizer to the frame.

[0153] According to this structure, the retaining component can retain the filter and polarizer without obstructing the light incident on them.

[0154] Appendix 4

[0155] According to any one of the appendices 1 to 3, the optical module wherein the filter is tilted at an angle θ1 from a state perpendicular to the optical axis, wherein 0° < θ1 ≤ 5°, and the polarizer is tilted at an angle θ2 from a state perpendicular to the optical axis to the side opposite to the filter, wherein 0° < θ2 ≤ 5°.

[0156] According to this structure, the filter and polarizer are configured at an appropriate angle relative to the optical axis, thus enabling the transmitted component of the excitation light that has been reflected between the filter and polarizer to be well emitted to the outside between the filter and polarizer.

[0157] Appendix 5

[0158] According to the optical module described in Appendix 4, the polarizer is configured perpendicular to the optical axis, and the filter is configured at an angle from a state perpendicular to the optical axis.

[0159] According to this structure, the polarizer, which is incident angle dependent, is configured perpendicular to the optical axis, thus enabling light to be efficiently incident on the polarizer.

[0160] Appendix 6

[0161] The optical module according to any one of Appendices 1 to 5, wherein the optical module further comprises: a light guide element disposed between the first light source and the filter for guiding light incident from the first light source; and a parallelizing element for making light incident from the light guide element parallel.

[0162] According to this structure, light emitted from the first light source can be guided to the subsequent stage in a parallel and efficient manner.

[0163] Appendix 7

[0164] According to the optical module described in Appendix 6, the light guide element has: a plurality of plates that divide a light guide path for guiding light incident from an incident end and emitted from an emitting end; and an adhesive that bonds the plurality of plates to the outside of the light guide path, the plurality of plates comprising: a first component having a first reflective surface; and a second component having a second reflective surface, wherein the contact area of ​​the adhesive with respect to the first component and the second component is larger at the emitting end relative to the middle portion of the light guide path than at the incident end relative to the middle portion.

[0165] Sometimes, a portion of the excitation light leaks outwards from the light guide path, becoming leakage light. Leakage light is light emitted towards the outer sides of the outer surfaces of multiple plates. While leakage light contains various angular components, leakage light emitted in a direction away from the outer surfaces of the multiple plates tends to incident on the side of the incident end of the light guide element. On the other hand, for the leakage light to reach the side of the emitting end of the light guide element, it needs to travel along the outer surfaces of the multiple plates. Thus, the amount of leakage light reaching the emitting end is significantly less than the amount incident on the incident end. Therefore, when the adhesive is placed on the incident end, the increased amount of leakage light can easily cause adhesive degradation. In contrast, according to this structure, the adhesive is placed closer to the emitting end than the incident end. Therefore, leakage light leaking from the incident opening of the light guide element is less likely to contact the adhesive, suppressing adhesive degradation. This, in turn, can suppress the reduction in the adhesive strength of the adhesive bonding the multiple plates.

[0166] Postscript 8

[0167] According to the optical module described in Appendix 7, the plurality of plates further include: a third component having a third reflective surface; and a fourth component having a fourth reflective surface, wherein the light guide path is formed by the first reflective surface of the first component facing the third reflective surface of the third component and the second reflective surface of the second component facing the fourth reflective surface of the fourth component.

[0168] Based on this structure, light guide elements can be easily manufactured using four plates.

[0169] Postscript 9

[0170] A projector comprising a first image forming module, the first image forming module including: an optical module as described in any one of Appendices 6 to 8; and a first light modulation element that modulates light incident from the polarizer of the optical module based on image information.

[0171] According to the projector structure, a highly reliable projector can be provided that suppresses the reliability reduction caused by multiple reflections of light in the first image forming module.

[0172] Postscript 10

[0173] According to the projector described in Appendix 9, the projector further comprises: a second image forming module, which includes a second light modulation element that modulates blue light incident from a second light source based on image information; a third image forming module, which includes a third light modulation element that modulates red light incident from a third light source based on image information; a light combining element that combines and emits green image light emitted from the first image forming module, blue image light emitted from the second image forming module, and red image light emitted from the third image forming module; and a projection optical system that projects light emitted from the light combining element, wherein the excitation light is light of 400nm to 450nm, and the light of different wavelengths is light of the green wavelength band.

[0174] According to this structure, in a three-panel projector equipped with image forming modules corresponding to the three colors, it is possible to suppress the decrease in reliability caused by multiple reflections of the excitation light in the green image forming module that uses short-wavelength excitation light.

Claims

1. An optical module comprising: The first light source includes a light-emitting element that emits excitation light and a wavelength conversion element that converts the excitation light into light of different wavelengths; A filter that blocks the excitation light contained in the light incident from the first light source; and A polarizing plate, through which light passing through the filter is incident on the polarizing plate. At least one of the filter and the polarizer is configured at an angle perpendicular to the optical axis, which is the optical axis of the light emitted from the first light source.

2. The optical module according to claim 1, wherein, The optical module also includes a holding component disposed between the filter and the polarizer, which holds the filter and the polarizer so that they are not parallel to each other.

3. The optical module according to claim 2, wherein, The retaining component includes: A frame-like body having an opening; and A fixing component, disposed around the opening, secures the filter and the polarizer to the frame.

4. The optical module according to claim 1, wherein, The filter is tilted at an angle θ1 from a position perpendicular to the optical axis, wherein 0° < θ1 ≤ 5°. The polarizing plate is tilted at an angle θ2 from a position perpendicular to the optical axis to the side opposite to the filter, where 0° < θ2 ≤ 5°.

5. The optical module according to claim 1, wherein, The polarizer is configured perpendicular to the optical axis. The filter is configured at an angle from a position perpendicular to the optical axis.

6. The optical module according to claim 1, wherein, The optical module also features: A light guide element, disposed between the first light source and the filter, guides light incident from the first light source; and A parallelizing element that makes the light incident from the light guide element parallel.

7. The optical module according to claim 6, wherein, The light guide element has: Multiple plates, which divide the light into light guide paths that guide light incident from the incident end and emitted from the emission end; and An adhesive is used to bond the plurality of plates to the outside of the light guide path. The plurality of plates include: a first component having a first reflective surface; And a second component, which has a second reflective surface, Regarding the contact area of ​​the adhesive relative to the first component and the second component, the contact area on the emission end side relative to the middle portion of the light guide is larger than the contact area on the incident end side relative to the middle portion.

8. The optical module according to claim 7, wherein, The plurality of plates further include: a third component having a third reflective surface; and a fourth component having a fourth reflective surface. The light guide path is formed by aligning the first reflective surface of the first component with the third reflective surface of the third component, and by aligning the second reflective surface of the second component with the fourth reflective surface of the fourth component.

9. A projector comprising a first image forming module, The first image forming module includes: The optical module according to any one of claims 6 to 8; and The first optical modulation element modulates the light incident from the polarizer of the optical module based on image information.

10. The projector according to claim 9, wherein, The projector also features: The second image forming module includes a second light modulation element that modulates blue light incident from the second light source based on image information; The third image forming module includes a third light modulation element that modulates red light incident from the third light source based on image information; A light combining element that combines and emits green image light emitted from the first image forming module, blue image light emitted from the second image forming module, and red image light emitted from the third image forming module; and A projection optical system that projects light emitted from the light-combining element. The excitation light is light in the range of 400nm to 450nm, and the light in different wavelength bands is light in the green band.

Images