Projector

Abstract

Provided is a projector. In a three-plate projector, the number of components is reduced, enlargement is suppressed, and the utilization efficiency of colored light is improved. In a projector according to an embodiment, first light of a first wavelength band emitted from a first light source passes through a first light guide element, a first parallelization element, and a light synthesis element in this order. Second light of a second wavelength band emitted from the second light source passes through the second light guide element and the second parallelization element in this order and is incident on the light synthesis element. Third light of a third wavelength band emitted from a third light source passes through a third light guide element and a third parallelization element in this order and is incident on a light synthesis element. A reflection portion is provided in a first surface side of the first light modulation element on which the first light is incident and in a region other than the opening portion of the display region.

Description

TECHNICAL FIELD

[0001] The utility model relates to a projector. BACKGROUND

[0002] In the past, as an image light generating means of each color light of 3 primary colors, a projector having 3 liquid crystal panels, i.e., a 3-panel type projector, is known. For example, Patent Literature 1 discloses a projector having a light source device having a light source section and a separation / synthesis element, an illumination optical system, a color separation / synthesis optical system, and a projection optical system. The light source section emits excitation light of a phosphor. The separation / synthesis element causes a part of the light emitted from the light source section to be incident on the phosphor and causes another part of the light emitted from the light source section to be incident on a diffuser and be reflected by the diffuser. The illumination optical system illuminates the light emitted from the light source device. The color separation / synthesis optical system performs color separation and color synthesis on the light emitted from the illumination optical system. The projection optical system enlarges and projects the image light after color synthesis to a screen or the like image display surface.

[0003] Patent Literature 1: Japanese Patent Application Publication No. 2020-079820

[0004] In the 3-panel type projector disclosed in Patent Literature 1, after white light is generated by the light source device, the white light is separated into each color light by the color separation / synthesis optical system disposed at a stage further back than the light source device. Therefore, the projector disclosed in Patent Literature 1 needs to have the color separation / synthesis optical system in addition to the light source device. As a result, the number of components increases, and the projector can be large-sized. That is, in the 3-panel type projector, a countermeasure to reduce the number of components and suppress the large size is desired. In addition, it is desired to improve the utilization efficiency of the color light. SUMMARY

[0005] One embodiment of the projector of this utility model includes: a first light source emitting first light of a first wavelength band; a second light source emitting second light of a second wavelength band different from the first wavelength band; a third light source emitting third light of a third wavelength band different from both the first and second wavelength bands; and a first light guide element having a first incident end and a first exiting end, wherein the first incident end receives the first light emitted from the first light source, and the first exiting end emits the first light. The first light guide element homogenizes the in-plane illuminance of the first light; the second light guide element has a second incident end and a second exit end, the second incident end receiving the second light emitted from the second light source, and the second exit end emitting the second light, the second light guide element homogenizing the in-plane illuminance of the second light; the third light guide element has a third incident end and a third exit end, the third incident end receiving the third light emitted from the third light source, and the third exit end emitting the third light. The third light guide element homogenizes the in-plane illuminance of the third light; the first parallelizing element parallelizes the first light emitted from the first light guide element; the second parallelizing element parallelizes the second light emitted from the second light guide element; the third parallelizing element parallelizes the third light emitted from the third light guide element; the first light modulation element modulates the first light emitted from the first parallelizing element based on image information; the second light modulation element modulates the second light emitted from the second parallelizing element based on image information; the third light modulation element modulates the third light emitted from the third parallelizing element based on image information; the light combining element combines the first light emitted from the first light modulation element, the second light emitted from the second light modulation element, and the third light emitted from the third light modulation element and emits them; and the projection optical system projects the light emitted from the light combining element. A reflective portion is provided in the first light modulation element on the first surface where the first light is incident, in the area other than the opening of the display area.

[0006] In one embodiment of the projector of this invention, the first light modulation element has a reflective portion on the first surface where the first light is incident and on the outer side of the display area. Attached Figure Description

[0007] Figure 1 This is a schematic diagram showing the structure of a projector according to one embodiment.

[0008] Figure 2 yes Figure 1 A schematic diagram of the green light emitting section of a projector.

[0009] Figure 3 yes Figure 1 A schematic diagram of the green light emitting section and the incident side polarizing element of the projector.

[0010] Figure 4 yes Figure 1 An exploded three-dimensional view of the light modulation element of a projector when green light is incident on it.

[0011] Figure 5 is Figure 1 a cross-sectional view of an incident side polarizing element and a light modulating element through which green light emitted from the projector of

[0012] Figure 6 is Figure 1 a schematic view of a light modulating element through which green light emitted from the projector of

[0013] Reference Signs List

[0014] 121 light source (2nd light source); 122 light source (1st light source); 123 light source (3rd light source); 141 light guide element (2nd light guide element); 142 light guide element (1st light guide element); 143 light guide element (3rd light guide element); 161 parallelization element (2nd parallelization element); 162 parallelization element (1st parallelization element); 163 parallelization element (3rd parallelization element); 181 light modulating element (2nd light modulating element); 182 light modulating element (1st light modulating element); 183 light modulating element (3rd light modulating element); 200 light synthesizing element; 250 projection optical system; 301 projector. DETAILED DESCRIPTION

[0015] Embodiments of the present application will be described below with reference to the drawings. In the drawings, the scale of the size of each component is sometimes changed in order to easily observe each component.

[0016] First, one embodiment of the present application will be described with reference to Figures 1 to 6 Figure 1 is a schematic view showing the structure of a projector 301 according to one embodiment of the present application. The projector 301 is an image display device having three liquid crystal panels as light modulating devices, and is a so-called 3-panel type projector. As shown in Figure 1

[0017] ​​The blue light emitting section 101 emits blue light LB. In the following description, a direction parallel to an optical axis of the blue light LB emitted from the blue light emitting section 101 is set as a D1 direction. A side in the D1 direction is set as a -D1 side, and a side opposite to the -D1 side in the D1 direction is set as a +D1 side. A direction perpendicular to the D1 direction in a plane including the optical axis of the blue light LB is set as a D2 direction. A side in the D2 direction is set as a -D2 side, and a side opposite to the -D2 side in the D2 direction is set as a +D2 side. A direction orthogonal to the D1 direction and the D2 direction is set as a D3 direction. The blue light LB emitted from the blue light emitting section 101 travels in the +D1 direction along the D1 direction.

[0018] The blue light emitting section 101 has a light source 121, a light guide member 141, and a parallelization member 161. The light source 121 is supported by the substrate 111. The light source 121 is disposed on the substrate 111 in a +D1 side plate surface among plate surfaces parallel to a plane including the D2 direction and the D3 direction. An emission surface of the light source 121 is disposed substantially parallel to the plane including the D2 direction and the D3 direction, and is a surface on an opposite side in the D1 direction from a surface of the light source 121 that is in contact with the +D1 side plate surface of the substrate 111. The light source 121 corresponds to a second light source, and emits blue light LB in a blue wavelength band in a visible wavelength band. The blue wavelength band corresponds to a second wavelength band. The blue light LB corresponds to second light. The blue light LB is emitted from the emission surface of the light source 121 in a diverging manner according to a prescribed emission angle, with an axis passing through a center of the emission surface of the light source 121 and parallel to the D1 direction as a center, and is emitted to the +D1 side. The blue wavelength band is, for example, a wavelength band of 420 nm to 500 nm.

[0019] The light source 121 is composed of, for example, a light emitting diode (LED) that emits the blue light LB. Furthermore, the light source 121 can be composed of one LED, or can be composed of a plurality of LEDs as a whole. In the case where the light source 121 is composed of a plurality of LEDs, the plurality of LEDs are arranged in an area occupied by the light source 121 in the plane including the D2 direction and the D3 direction.

[0020] The substrate 111 is composed of, for example, a metal, and functions also as a heat dissipation member that receives heat from the light source 121 that emits the blue light LB and releases the heat to the outside.

[0021] The light guide member 141 is disposed on the light path of the blue light LB emitted from the light source 121, at a position on the +D1 side of the light source 121 and overlapping the light source 121 in the D2 direction and the D3 direction. The light guide member 141 corresponds to a second light guide member, and has an incident end 141a on the -D1 side in the D1 direction, an emission end 141b on the +D1 side, and a side surface 141s and a reflection surface 141r extending between the incident end 141a and the emission end 141b in the D1 direction. The incident end 141a corresponds to a second incident end, and extends in parallel with a plane including the D2 direction and the D3 direction.

[0022] The shape of the incident end 141a when viewed from the D1 direction is the same as the shape of the light emitting surface of the light source 121 when viewed from the same direction, for example, a rectangle. The size of the incident end 141a on a plane including the D2 direction and the D3 direction can be the same as the size of the light emitting surface of the light source 121 on a plane including the D2 direction and the D3 direction, but is preferably appropriately larger than the size of the light emitting surface of the light source 121 on a plane including the D2 direction and the D3 direction. The emission end 141b corresponds to a second emission end, and extends in parallel with a plane including the D2 direction and the D3 direction, and is larger than the incident end 141a. The shape of the emission end 141b when viewed from the D1 direction is the same as the shape of the modulation surface of the light modulation member 181 when viewed from the same direction, for example, a rectangle. The size of the emission end 141b on a plane including the D2 direction and the D3 direction is the same as the size of the modulation surface of the light modulation member 181 on a plane including the D2 direction and the D3 direction. The side surface 141s and the reflection surface 141r connect a peripheral edge portion of the incident end 141a and a peripheral edge portion of the emission end 141b in the D1 direction.

[0023] The blue light LB emitted from the light source 121 is incident on the light guide member 141 from the incident end 141a. In the light guide member 141, a region surrounded by the incident end 141a, the emission end 141b, and the reflection surface 141r is a region in which the blue light LB propagates. The size of the region surrounded by the incident end 141a, the emission end 141b, and the reflection surface 141r on a plane including the D2 direction and the D3 direction increases as it advances from the -D1 side to the +D1 side in the D1 direction. Furthermore, the shape of the region surrounded by the incident end 141a, the emission end 141b, and the reflection surface 141r on a plane including the D2 direction and the D3 direction changes from the shape of the light emitting surface of the light source 121 when viewed from the D1 direction to the shape of the modulation surface of the light modulation member 181 as it advances from the -D1 side to the +D1 side.

[0024] The side surface 141s of the light guide member 141 and the reflection surface 141r provided on the side surface 141s as described later are at a prescribed angle with respect to the imaginary line perpendicular to the incident end 141a and the optical axis, and move away from the imaginary line in a plane including the D2 direction and the D3 direction as they move from the -D1 side to the +D1 side. Blue light LB incident on the light guide member 141 propagates from the -D1 side to the +D1 side within an area surrounded by the incident end 141a, the emission end 141b, and the reflection surface 141r.

[0025] In the case where the shape of the modulation surface of the light modulation element 181 when viewed along the D1 direction is a long rectangle, the shape of the light emitting surface of the light source 121 when viewed along the D1 direction is a long rectangle similar to the modulation surface of the light modulation element 181. In this case, the prescribed angle α, i.e., the taper angle, that the side surface 141s including the short side of the long rectangle and the reflection surface 141r make with respect to the aforementioned imaginary line and the optical axis is preferably in the range of 7° to 22°. The prescribed angle β, i.e., the taper angle, that the side surface 141s including the long side of the long rectangle and the reflection surface 141r make with respect to the aforementioned imaginary line and the optical axis is preferably in the range of 14° to 36°. The preferable ranges of the angles α and β are confirmed by numerical simulation based on the structure of the blue light emission portion 101 and ray tracing.

[0026] A portion of the blue light LB incident on the light guide member 141 propagates in a direction at an angle smaller than the prescribed angle with respect to the aforementioned imaginary line and the optical axis, does not incident on the reflection surface 141r at all, and directly propagates from the incident end 141a to the emission end 141b. The remaining portion of the blue light LB incident on the light guide member 141 is at an angle of 90° or more with respect to the aforementioned imaginary line and the optical axis, is incident on the reflection surface 141r one or more times from the incident end 141a, and reaches the emission end 141b after being reflected by the reflection surface 141r. The paths of the rays of the blue light LB within the area surrounded by the incident end 141a, the emission end 141b, and the reflection surface 141r differ depending on the incident angle of incidence on the incident end 141a, and involve a plurality of paths that differ in the number of times of reflection at the reflection surface 141r. As a result, the illuminance distribution of the blue light LB propagating in the area surrounded by the incident end 141a, the emission end 141b, and the reflection surface 141r is uniformized in the plane including the D2 direction and the D3 direction. That is, the light guide member 141 uniformizes the illuminance distribution of the incident blue light LB in the plane including the D2 direction and the D3 direction. The blue light LB whose illuminance distribution is uniformized is emitted from the emission end 141b toward the +D1 side.

[0027] The light guide member 141 is, for example, a reflector composed of a transparent material such as optical glass. The light guide member 141 has a frame that is formed as a hollow member. The end of the frame of the light guide member 141 on the -Dl side has the same shape and size as the incidence end 141a and the light emitting surface of the light source 121, for example, and is formed as a rectangular frame when viewed in the Dl direction. The end of the frame of the light guide member 141 on the +Dl side has the same shape and size as the emission end 141b and the modulation surface of the light modulation element 181, for example, and is formed as a rectangular frame that is different in size from the end on the -Dl side.

[0028] The light guide member 141 is, for example, composed of plate-shaped members composed of a transparent material. As described above, if the shape of the incidence end 141a and the emission end 141b when viewed in the Dl direction is rectangular, the light guide member 141 is composed of four plate-shaped members having a trapezoidal shape. The length of the edge on the -Dl side that is parallel to the D2 direction or the D3 direction, which corresponds to the upper base of the four plate-shaped members, is set in accordance with the size of the incidence end 141a and the light emitting surface of the light source 121 in the D2 direction or the D3 direction. The length of the edge on the +Dl side that is parallel to the D2 direction or the D3 direction, which corresponds to the lower base of the four plate-shaped members, is set in accordance with the size of the emission end 141b and the modulation surface of the light modulation element 181 in the D2 direction or the D3 direction. In the four plate-shaped members, the edge that corresponds to one side of the waist of one of the two plate-shaped members is connected to the edge that corresponds to the other side of the waist of the other one of the two plate-shaped members.

[0029] If the light guide member 141 is composed of plate-shaped members composed of a transparent material as described above, the side surface 141s, that is, the plate surface in the plate-shaped members that faces the outside space of the light guide member 141, functions as a reflection surface 141r. In the light guide member 141, in order to increase the reflectance of the blue light LB that is incident on the light guide member 141 from the incidence end 141a in the vicinity of the side surface 141s, a reflection film 251 composed of a dielectric multilayer film or the like is provided on the plate surface in the plate-shaped member that constitutes the reflector that faces the inside space of the light guide member 141. A portion of the blue light LB that is incident on the inside space of the light guide member 141 from the incidence end 141a is reflected by the reflection film 251 and travels in the +Dl direction.

[0030] The intensity of the blue light LB that is reflected by the reflecting film 251 and emitted from the reflecting film 251 sometimes depends on the incident angle of the blue light LB incident to the reflecting film 251. In the case where the reflecting film 251 is constituted by a dielectric multilayer film, for example, the incident angle dependence of the intensity of the blue light LB emitted from the reflecting film 251 changes depending on parameters such as the refractive indexes of the plurality of films included in the dielectric multilayer film, the thickness of the films, the number of the films, and the like. As described above, for example, in the case where the angle a is in the range of 7° to 22° and the angle β is in the range of 14° to 36°, the reflecting film 251 is designed so that the incident angle of the blue light LB of which the intensity of the blue light LB emitted from the reflecting surface 141r is the highest becomes in the range of 60° to 90°, and the parameters of the dielectric multilayer film are appropriately decided. The relationship between the incident angle of the blue light LB to the reflecting surface 141r and the reflecting film 251 and the intensity of the blue light LB emitted from the reflecting surface 141r and the reflecting film 251 is obtained by numerical simulation based on the structure of the blue light emission portion 101 and ray tracing.

[0031] In addition, in the case where the light guide member 141 is constituted by a plate-shaped member constituted by a transparent member, and the plate surface of the plate-shaped member facing the outside space of the light guide member 141 functions as the reflecting surface 141r, a part of the blue light LB incident to the inside space of the light guide member 141 from the incident end 141a is incident to the plate-shaped member from the plate surface of the plate-shaped member facing the inside space of the light guide member 141, refracted, reflected at the plate surface facing the outside space of the light guide member 141, propagated again in the plate-shaped member, refracted at the plate surface facing the inside space of the light guide member 141, emitted to the inside space, and travels in the +D1 direction.

[0032] The parallelizing member 161 is provided on the optical path of the blue light LB emitted from the light guide member 141, and is disposed at a position on the +D1 side of the light guide member 141 and overlapping the light guide member 141 in the D2 direction and the D3 direction. The parallelizing member 161 corresponds to a second parallelizing member, and parallelizes the blue light LB emitted from the light guide member 141 in the D1 direction.

[0033] The parallelizing element 161 is, for example, a plano-convex lens having an incident surface composed of a flat surface orthogonal to the D1 direction and an exit surface composed of a convex curved surface protruding toward the exit side of the blue light LB. The focal point Fl of the plano-convex lens constituting the parallelizing element 161 is located at least on the -D1 side from the parallelizing element 161 and on the side opposite to the +D1 side from which the blue light LB exits the parallelizing element 161, and further on the -D1 side from the light guide element 141. The incident surface of the plano-convex lens of the parallelizing element 161 is in contact with the exit end 141b of the light guide element 141. By bringing the parallelizing element 161 into contact with the exit end 141b, the blue light LB exiting the exit end 141b of the light guide element 141 is taken into the parallelizing element 161 to the maximum extent, and loss of the blue light LB can be suppressed. However, the parallelizing element 161 can also be an optical lens other than a plano-convex lens that can parallelize the incident blue light LB, and can be disposed at an appropriate interval from the light guide element 141 in the D1 direction.

[0034] The focal length fl of the parallelizing element 161 is longer than the length gl in the D1 direction from the incident end 141a to the exit end 141b of the light guide element 141. The focal length fl of the parallelizing element 161 is, for example, preferably 1.1 times or more the length gl of the light guide element 141, and more preferably 1.1 times or more the length gl and 2.0 times or less the length gl. By setting the focal length fl within the above range, the blue light LB exiting the light source 121 is efficiently parallelized, and the utilization efficiency of the blue light LB is improved. The preferable range of the focal length fl is confirmed by numerical simulation based on the structure of the blue light exit portion 101 and ray tracing.

[0035] The incident-side polarization element 171 is disposed on the optical path of the blue light LB exiting the parallelizing element 161, and is disposed on the +D1 side from the parallelizing element 161 and overlaps the parallelizing element 161 in the D2 direction and the D3 direction. The incident-side polarization element 171 is, for example, in contact with the light modulating element 181 from the -D1 side, but can also be disposed at an appropriate interval from the light modulating element 181 in the D1 direction. The incident-side polarization element 171 corresponds to a second polarization element, and causes a predetermined polarized light among the blue light LB exiting the parallelizing element 161 to exit toward the +D1 side along the D1 direction. The predetermined polarized light corresponds to a second polarization component, and is, for example, S-polarized light.

[0036] The incident-side polarizing element 171 is, for example, a reflective polarizing plate or an absorptive polarizing plate having a plate surface parallel to a plane including the D2 direction and the D3 direction. In addition, in a case where it is desired to suppress return light and stray light to an optical element in a stage preceding the parallelizing element 161, it is preferable to employ an absorptive polarizing plate as the incident-side polarizing element 171. The incident-side polarizing element 171 transmits a portion of the incident blue light LB including a prescribed polarized light to the +D1 side and reflects or absorbs another portion of the blue light LB to the -D1 side.

[0037] In addition, the blue light LB emitted from the light source 121 includes at least P-polarized light and S-polarized light, and is, for example, random polarized light. The S-polarized component in the blue light LB emitted from the light source 121 passes through the light guide element 141 and the parallelizing element 161 in that order as described above, transmits through the incident-side polarizing element 171, and is emitted to the +D1 side from the incident-side polarizing element 171. The P-polarized component in the blue light LB is the same as the S-polarized component, passes through the light guide element 141 and the parallelizing element 161 in that order, but is reflected or absorbed by the incident surface of the incident-side polarizing element 171, and is emitted to the +D1 side from the incident-side polarizing element 171.

[0038] The light modulating element 181 is disposed on an optical path of the blue light LB emitted from the incident-side polarizing element 171, and is disposed at a position overlapping the incident-side polarizing element 171 in the D2 direction and the D3 direction and on the +D1 side from the incident-side polarizing element 171. The light modulating element 181 corresponds to a second light modulating element, and modulates the blue light LB emitted from the incident-side polarizing element 171 in accordance with image information transmitted from an unillustrated computer or the like image forming apparatus connected to the light modulating element 181 from the outside.

[0039] The light modulating element 181 is, for example, a transmissive liquid crystal panel. The liquid crystal panel constituting the light modulating element 181 has a plurality of pixels unillustrated. Each pixel has a switching element. The switching element is, for example, a polysilicon thin film transistor (TFT). An electric signal corresponding to the luminance of red light at a relative position of each pixel in a modulation plane of the light modulating element 181 in an image projected by the projector 301 is supplied to the switching element of each pixel. Each pixel generates blue image light IB by modulating the vibration direction of the blue light LB incident from the incident-side polarizing element 171 through the action of the switching element corresponding to the above-mentioned electric signal. The image light IB corresponds to a second light. The light modulating element 181 emits the image light IB generated by the liquid crystal panel to the +D1 side along the D1 direction.

[0040] The emission-side polarizing element 175 is disposed on the optical path of the image light IB emitted from the light modulating element 181, and is disposed at a position on the +D1 side of the light modulating element 181 and overlapping the light modulating element 181 in the D2 direction and the D3 direction. The emission-side polarizing element 175 is, for example, in contact with the light modulating element 181 from the +D1 side, but can also be disposed at an appropriate interval from the light modulating element 181 in the D1 direction. The emission-side polarizing element 175 corresponds to a fifth polarizing element, and emits a prescribed polarized light in the image light IB emitted from the light modulating element 181 in the D1 direction toward the +D1 side. The prescribed polarized light corresponds to a fifth polarization component, and is, for example, P-polarized light.

[0041] The emission-side polarizing element 175 is, for example, a reflective-type polarizing plate or an absorptive-type polarizing plate having a plate surface parallel to a surface including the D2 direction and the D3 direction. In addition, in a case where it is desired to suppress return light and stray light to the light modulating element 181, it is preferable to employ an absorptive-type polarizing plate as the emission-side polarizing element 175. The emission-side polarizing element 175 transmits a portion of the incident image light IB including the prescribed polarized light toward the +D1 side, and reflects or absorbs another portion of the image light IB toward the -D1 side.

[0042] The green light emission portion 102 is disposed at a position on the +D1 side and the -D2 side of the blue light emission portion 101, and is disposed in a region overlapping the blue light emission portion 101 in the D3 direction. The green light emission portion 102 emits green light LG. The green light LG emitted from the green light emission portion 102 travels in the D2 direction toward the +D2 side.

[0043] The green light emission portion 102 has a light source 122, a light guide element 142, and a parallelization element 162. Figure 2 is a schematic view of the green light emission portion 102, and is a view when the green light emission portion 102 is viewed in the D3 direction. As shown in Figure 2 The light source 122 is supported by the substrate 112. The light source 122 is disposed in the +D2 side plate surface among the plate surfaces parallel to a surface including the D1 direction and the D3 direction in the substrate 112. The light emitting surface 122a of the light source 122 is disposed substantially parallel to the surface including the D1 direction and the D3 direction, and is a surface on the opposite side in the D2 direction from the surface of the light source 122 in contact with the +D2 side plate surface of the substrate 112. The light source 122 corresponds to a first light source, and emits green light LG in a green band in the visible band. The green band corresponds to a first band. The green light LG corresponds to a first light. The green band is, for example, a band of 500 nm to 600 nm.

[0044] The light source 122 is, for example, an LED that emits green light LG. In the green light emission section 102, in order to optimize the green wavelength band and intensity of the green light LG with respect to the blue wavelength band and intensity of the blue light LB emitted by the blue light emission section 101 and the red wavelength band and intensity of the red light LR emitted by the red light emission section 103, the light source 122 is composed of an LED with a built-in phosphor, has an LED main body 125 composed of a semiconductor, and a phosphor 124.

[0045] The LED main body 125 is disposed on the plate surface on the +D2 side of the substrate 112. The LED main body 125 corresponds to the light emitter of the light source 122 and is, for example, an LED that emits blue light LB like the light source 121. The phosphor 124 is laminated on the emission surface 125a on the +D2 side of the LED main body 125. The phosphor 124 is excited by the light emitted from the LED main body 125 as excitation light and emits green light LG as phosphor light from the emission surface 124a. The kind and material of the LED main body 125 and the kind and material of the phosphor 124 are appropriately selected so that the phosphor 124 excited by the light emitted from the LED main body 125 emits green light LG of the green wavelength band.

[0046] Further, the LED main body 125 can be composed of one LED like the light source 121 or can be composed of a plurality of LEDs as a whole. In the case where the LED main body 125 is composed of a plurality of LEDs, the plurality of LEDs are arranged in the area occupied by the light source 122 in the plane including the D1 direction and the D3 direction.

[0047] The substrate 112 is composed of, for example, metal and functions also as a heat releasing member that receives heat from the light source 122 that emits green light LG and releases the heat to the outside.

[0048] The light guide member 142 is disposed on the optical path of the green light LG emitted from the light source 122 and is disposed at a position on the +D2 side of the light source 122 and overlapping the light source 122 in the D1 direction and the D3 direction. The light guide member 142 corresponds to the first light guide member and has an incident end 142a on the -D2 side in the D2 direction, an emission end 142b on the +D2 side, and a side surface 142s and a reflection surface 142r extending between the incident end 142a and the emission end 142b in the D2 direction.

[0049] The incident end 142a corresponds to a first incident end and extends in parallel with the plane including the D1 direction and the D3 direction. The shape of the incident end 142a when viewed from the D2 direction is the same as the shape of the light emitting surface 122a of the light source 122 when viewed from the same direction, for example, a rectangle. The size of the incident end 142a on the plane including the D1 direction and the D3 direction can be the same as the size of the light emitting surface 122a of the light source 122 on the plane including the D1 direction and the D3 direction, but is preferably appropriately larger than the size of the light emitting surface 122a on the plane including the D1 direction and the D3 direction.

[0050] The exit end 142b corresponds to a first exit end and extends in parallel with the plane including the D1 direction and the D3 direction, and is larger than the incident end 142a. The shape of the exit end 142b when viewed from the D2 direction is the same as the shape of the modulation surface of the light modulation element 182 when viewed from the same direction, for example, a rectangle. The size of the exit end 142b on the plane including the D1 direction and the D3 direction is equal to the size of the modulation surface of the light modulation element 182 on the plane including the D1 direction and the D3 direction. The side surface 142s and the reflection surface 142r connect the peripheral edge portion of the incident end 142a and the peripheral edge portion of the exit end 142b in the D2 direction.

[0051] The green light LG emitted from the light source 122 is incident on the light guide element 142 from the incident end 142a. In the light guide element 142, the region surrounded by the incident end 142a, the exit end 142b, and the reflection surface 142r is a region in which the green light LG propagates. The size of the region surrounded by the incident end 142a, the exit end 142b, and the reflection surface 142r on the plane including the D1 direction and the D3 direction increases as it advances from the -D2 side to the +D2 side in the D2 direction. Furthermore, the shape of the region surrounded by the incident end 142a, the exit end 142b, and the reflection surface 142r on the plane including the D1 direction and the D3 direction changes from the shape of the light emitting surface 122a of the light source 122 when viewed from the D2 direction to the shape of the modulation surface of the light modulation element 182 as it advances from the -D2 side to the +D2 side.

[0052] The side surface 142s of the light guide element 142 and the reflection surface 142r provided to the side surface 142s as described later form a predetermined angle with respect to the virtual line VX orthogonal to the incident end 142a and the optical axis, and move away from the virtual line on the plane including the D2 direction and the D3 direction as it moves from the -D2 side to the +D2 side. The green light LG incident on the light guide element 142 propagates from the -D2 side to the +D2 side within the region surrounded by the incident end 142a, the exit end 142b, and the reflection surface 142r.

[0053] In the case where the shape of the modulating surface of the light modulating element 182 as viewed in the D2 direction is a long rectangle, the shape of the light emitting surface 122a of the light source 122 as viewed in the D2 direction is a long rectangle in a substantially similar relationship to the modulating surface of the light modulating element 182. In this case, the prescribed angle a that the side surface 142s including the short side of the long rectangle and the reflecting surface 142r make with respect to the above-mentioned virtual line and the optical axis is preferably in the range of 7° to 22°. The prescribed angle β that the side surface 142s including the long side of the long rectangle and the reflecting surface 142r make with respect to the above-mentioned virtual line and the optical axis is preferably in the range of 14° to 36°.

[0054] A portion of the green light LG that is incident on the light guide element 142, light ray Lg1, forms an angle smaller than the angle a or the angle β with respect to the virtual line VX and the optical axis, is not incident on the reflecting surface 142r even once, and propagates directly from the incident end 142a to the emission end 142b. The remaining portion of the green light LG that is incident on the light guide element 142, light ray Lg2, forms an angle of 8 or more with respect to the virtual line VX and the optical axis, is incident on the reflecting surface 142r once from the incident end 142a, reaches the emission end 142b after being reflected by the reflecting surface 142r. The light rays other than the light ray Lg2 that are incident on the light guide element 142 are incident on the reflecting surface 142r from the incident end 142a two or more times, reach the emission end 142b after being repeatedly reflected by the reflecting surface 142r.

[0055] The paths of the light rays of the green light LG in the internal space surrounded by the incident end 142a, the emission end 142b, and the reflecting surface 142r of the light guide element 142 differ depending on the incident angle with respect to the incident end 142a, and involve a plurality of paths in which the number of times of reflection in the reflecting surface 142r differs from one another. As a result, the illuminance distribution of the green light LG propagating in the internal space of the light guide element 142 is homogenized in the plane including the D1 direction and the D3 direction. That is, the light guide element 142 homogenizes the illuminance distribution of the incident green light LG in the plane including the D1 direction and the D3 direction. The green light LG whose illuminance distribution is homogenized is emitted from the emission end 142b toward the +D2 side.

[0056] The light guide element 142, like the light guide element 141, is a hollow reflector constituted by, for example, a plate-shaped member constituted by a transparent material such as optical glass. The end portion of the frame of the reflector on the -D2 side as viewed in the D2 direction has the same shape and size as the incident end 142a and the light emitting surface 122a of the light source 122, and is formed in, for example, a rectangular frame shape. The end of the frame of the reflector on the +D2 side has the same shape and size as the emission end 142b and the modulating surface of the light modulating element 182, and is formed in, for example, a rectangular frame shape that is different in size from the end on the -D2 side.

[0057] The reflector of the light guide member 142 is configured by connecting the edges corresponding to the waists of four plate-like members having a trapezoidal shape to each other. The length of the edge on the -D2 side corresponding to the upper base of the four plate-like members and parallel to the D1 direction or the D3 direction is set according to the size of the D1 direction or the D3 direction of the light emission surface 122a and the incident end 142a. The length of the edge on the +D2 side corresponding to the lower base of the four plate-like members and parallel to the D1 direction or the D3 direction is set according to the size of the D1 direction or the D3 direction of the modulation surface of the light modulation member 182 and the exit end 142b.

[0058] In the reflector of the light guide member 142, in order to improve the reflectance of the green light LG incident to the light guide member 142 from the incident end 142a near the side surface 142s, a reflection film 252 such as a dielectric multilayer film is provided on the plate surface of the plate-like member on the side opposite to the side surface 142s, that is, on the plate surface facing the internal space of the plate-like member. Part of the green light LG including the light ray Lg2 incident to the internal space of the reflector of the light guide member 142 from the incident end 142a is reflected by the reflection film 252 and travels in the +D1 direction.

[0059] The intensity of the green light LG emitted from the reflection film 252 by being reflected by the reflection film 252 sometimes depends on the incident angle of the green light LG incident to the reflection film 252. In the case where the reflection film 252 is configured by a dielectric multilayer film, for example, the incident angle dependence of the intensity of the green light LG emitted from the reflection film 252 changes according to parameters such as the refractive indexes of the plurality of films included in the dielectric multilayer film, the thickness of the films, the number of the films, and the like. As described above, for example, in the case where the angle a is in the range of 7° to 22° and the angle β is in the range of 14° to 36°, the reflection film 252 is designed so that the incident angle of the green light LG having the highest intensity of the green light LG emitted from the reflection surface 142r and the reflection film 252 becomes in the range of 60° or more and 90° or less, and the parameters of the dielectric multilayer film are appropriately decided. The relationship between the incident angle of the green light LG to the reflection film 252 and the intensity of the green light LG emitted from the reflection film 252 is also obtained by numerical simulation based on the structure of the green light emission portion 102 and light ray tracing.

[0060] In addition, in the case where the light guide member 142 is configured by a plate-like member configured by a transparent member and the plate surface of the plate-like member facing the external space of the light guide member 142 functions as the reflection surface 142r, part of the green light LG incident to the internal space of the light guide member 142 from the incident end 142a is incident to the plate-like member from the plate surface of the plate-like member facing the internal space of the light guide member 142, is refracted, is reflected by the plate surface of the plate-like member facing the external space of the light guide member 142, propagates in the plate-like member again, is refracted by the plate surface of the plate-like member facing the internal space of the light guide member 142, is emitted to the internal space of the light guide member 142, and travels in the +D2 direction.

[0061] The parallelizing element 162 is disposed on the optical path of the green light LG emitted from the light guide element 142, and is disposed at a position on the +D2 side of the light guide element 142 and overlapping the light guide element 142 in the D1 direction and the D3 direction. The parallelizing element 162 corresponds to a first parallelizing element, and parallelizes the green light LG emitted from the light guide element 142 in the D2 direction.

[0062] The parallelizing element 162 is, for example, a plano-convex lens having an incident surface 162a constituted by a flat surface orthogonal to the D2 direction and an emission surface 162b constituted by a convex curved surface projecting toward the emission side of the blue light LB. The focal point F2 of the plano-convex lens constituting the parallelizing element 162 is located at least on the -D2 side of the parallelizing element 162, on the side opposite to the +D2 side from which the green light LG is emitted from the parallelizing element 162, and further on the -D2 side of the light guide element 142. The incident surface 162a of the parallelizing element 162 is in contact with the emission end 142b of the light guide element 142. By the incident surface 162a of the parallelizing element 162 being in contact with the emission end 142b, the green light LG emitted from the emission end 142b of the light guide element 142 is taken into the parallelizing element 162 to the maximum extent, and loss of the green light LG can be suppressed. However, the parallelizing element 162 can also be an optical lens other than a plano-convex lens that can parallelize the incident green light LG, and can be disposed at an appropriate interval from the light guide element 142 in the D2 direction.

[0063] The focal length f2 of the parallelizing element 162 is longer than the length g2 in the D2 direction from the incident end 142a to the emission end 142b of the light guide element 142. The focal length f2 of the parallelizing element 162 is, for example, preferably 1.1 times or more the length g2 of the light guide element 142, and more preferably 1.1 times or more the length g2 and 2.0 times or less the length g2. By setting the focal length f2 within the above range, the green light LG emitted from the light source 122 is efficiently parallelized, and the utilization efficiency of the green light LG is improved. The preferable range of the focal length f2 is confirmed by numerical simulation based on the structure of the green light emission portion 102 and ray tracing.

[0064] Figure 3 is a schematic view of the green light emission portion 102 and the incident-side polarization element 172, and is a view when the green light emission portion 102 and the incident-side polarization element 172 are viewed in the D3 direction. As shown in Figure 3 The incident-side polarization element 172 is disposed on the optical path of the green light LG emitted from the parallelizing element 162, and is disposed at a position on the +D2 side of the parallelizing element 162 and overlapping the parallelizing element 162 in the D1 direction and the D3 direction. The incident-side polarization element 172 can be in contact with the light modulation element 182 from the +D2 side, as exemplified in Figure 1 , or can be disposed at an appropriate interval from the light modulation element 182 in the D2 direction, as exemplified in Figure 3is disposed at an appropriate interval apart from the light modulating element 182 in the D2 direction as exemplified.

[0065] The incident-side polarizing element 172 corresponds to a first polarizing element, and causes a prescribed polarized light in the green light LG emitted from the parallelizing element 162 to be emitted toward the +D2 side along the D2 direction. The prescribed polarized light corresponds to a first polarizing component, and is, for example, an S-polarized light. The incident-side polarizing element 172 is, for example, a reflective-type polarizing plate or an absorption-type polarizing plate having a plate surface parallel to a plane including the D1 direction and the D3 direction. The incident-side polarizing element 172 transmits a portion of the incident green light LG including the prescribed polarized light toward the +D2 side, and reflects another portion of the green light LG toward the -D2 side.

[0066] As Figure 3 As exemplified in detail, the green light LG emitted from the light source 122 is a random polarized light including at least a P-polarized light and an S-polarized light. The S-polarized component in the green light LG emitted from the light source 122, i.e., the green light LGS, and the P-polarized component in the green light LG, i.e., the green light LGP, are totally reflected in the light guide element 142 according to the angle of emission from the light source 122 as described above, and are guided to the +D2 side as the green light LG, and are homogenized in the plane including the D1 direction and the D3 direction by the light guide element 142, and are further emitted to the +D2 side than the light guide element 142. The green light LGS, LGP passes through the parallelizing element 162, and is parallelized by the parallelizing element 162. The parallelized green light LGS, LGP is incident on the incident-side polarizing element 172 from the -D2 side. The green light LGS transmits the incident-side polarizing element 172, and is emitted to the +D2 side than the incident-side polarizing element 172. The green light LGP is absorbed or reflected by the incident surface 172a of the incident-side polarizing element 172, and is emitted to the -D2 side than the incident-side polarizing element 172.

[0067] In the case where the green light LGP is reflected from the incident-side polarizing element 172 to the -D2 side, the green light LGP sequentially passes through the parallelizing element 162 and the light guide element 142, travels along the D2 direction toward the -D2 side, converges in the plane including the D1 direction and the D3 direction, and is incident on the phosphor 124 of the light source 122 from the +D2 side. The phosphor 124 is excited again by the green light LGP emitted from the incident-side polarizing element 172 to the -D2 side, and emits the green light LG including the green light LGS, LGP again from the emission surface 124a to the +D2 side. The incident-side polarizing element 172 is constituted by a reflective-type polarizing plate, and thus, the polarized light of the green light LG not transmitted through the incident-side polarizing element 172 is incident on the phosphor 124 of the light source 122 again, and contributes to the excitation and emission of the phosphor 124. As a result, the utilization efficiency of the green light LG in the green light emitting portion 102 and the projector 301 is improved.

[0068] AsFigure 1 As shown, the light modulating element 182 is disposed on the optical path of the green light LG emitted from the incident-side polarizing element 172, at a position on the +D2 side from the incident-side polarizing element 172 and overlapping the incident-side polarizing element 172 in the Dl direction and the D3 direction. The light modulating element 182 corresponds to a first light modulating element, and modulates the green light LG emitted from the incident-side polarizing element 172 in accordance with image information transmitted from an image forming apparatus such as a computer not shown, which is connected to the light modulating element 182 from the outside.

[0069] The light modulating element 182 is, for example, a transmissive liquid crystal panel. The liquid crystal panel constituting the light modulating element 182 has a plurality of pixels not shown. Each pixel has a switching element. The switching element is, for example, a TFT. An electric signal corresponding to the luminance of the green light at the relative position of each pixel in the modulation plane of the light modulating element 182 in the image projected by the projector 301 is supplied to the switching element of each pixel. Each pixel modulates the vibration direction of the green light LG incident from the incident-side polarizing element 172 by the action of the switching element corresponding to the above-mentioned electric signal, and generates green image light IG. The image light IG corresponds to first light. The light modulating element 182 emits the image light IG generated by the liquid crystal panel along the D2 direction toward the +D2 side.

[0070] The emission-side polarizing element 176 is disposed on the optical path of the image light IG emitted from the light modulating element 182, at a position on the +D2 side from the light modulating element 182 and overlapping the light modulating element 182 in the Dl direction and the D3 direction. The emission-side polarizing element 176 is, for example, in contact with the light modulating element 182 from the +D2 side, but can also be disposed at an appropriate interval apart from the light modulating element 182 in the D2 direction. The emission-side polarizing element 176 corresponds to a fourth polarizing element, and emits a prescribed polarized light in the image light IG emitted from the light modulating element 182 along the D2 direction toward the +D2 side. The prescribed polarized light corresponds to a fourth polarization component, and is, for example, P-polarized light. The emission-side polarizing element 176 is, for example, a reflective polarizing plate or an absorptive polarizing plate having a plate surface parallel to the plane including the Dl direction and the D3 direction. In addition, in the case where it is desired to suppress return light and stray light to the light modulating element 182, it is preferable to employ an absorptive polarizing plate as the emission-side polarizing element 176. The emission-side polarizing element 176 transmits a portion of the incident image light IG including the prescribed polarized light toward the +D2 side, and reflects or absorbs another portion of the image light IG toward the -D2 side.

[0071] As Figure 1As shown, the red light emitting portion 103 is disposed at a position on the +Dl side of the green light emitting portion 102, in a region overlapping the blue light emitting portion 101 in the D2 direction and the D3 direction. The red light emitting portion 103 emits red light LR. The red light LR emitted from the red light emitting portion 103 travels in the -Dl direction toward the -Dl side.

[0072] The red light emitting portion 103 has a light source 123, a light guide member 143, and a parallelizing member 163. The light source 123 is supported by the substrate 113. The light source 123 is disposed in the -Dl side of the plate surface in the substrate 113 in a plate surface parallel to the surface including the D2 direction and the D3 direction. The light emitting surface of the light source 123 is disposed substantially parallel to the surface including the D2 direction and the D3 direction, and is a surface on the opposite side of the Dl direction from the surface of the light source 123 that is in contact with the -Dl side of the plate surface of the substrate 113. The light source 123 corresponds to a third light source, and emits red light LR in a red wavelength band in the visible wavelength band. The red wavelength band corresponds to a third wavelength band. The red light LR corresponds to a third light. The red light LR is emitted from the light emitting surface of the light source 123 in a diverging manner according to a prescribed emission angle, with an axis passing through the center of the light emitting surface of the light source 123 and parallel to the Dl direction as a center, toward the -Dl side. The red wavelength band is, for example, a wavelength band of 610 nm to 700 nm.

[0073] The light source 123 is composed of, for example, an LED that emits red light LR. Furthermore, the light source 123 can be composed of one LED, or can be composed of a plurality of LEDs as a whole. In the case where the light source 123 is composed of a plurality of LEDs, the plurality of LEDs are arranged in the region occupied by the light source 123 in the surface including the D2 direction and the D3 direction.

[0074] The substrate 113 is composed of, for example, metal, and also functions as a heat releasing member that receives heat from the light source 123 that emits red light LR and releases the heat to the outside.

[0075] The light guide member 143 is disposed on the optical path of the red light LR emitted from the light source 123, and is disposed at a position on the -Dl side of the light source 123 and overlapping the light source 123 in the D2 direction and the D3 direction. The light guide member 143 corresponds to a third light guide member, and has a -Dl side incident end 143a in the Dl direction, a +Dl side emission end 143b, and a side surface 143s and a reflection surface 143r extending between the incident end 143a and the emission end 143b in the Dl direction. The incident end 143a corresponds to a third incident end, and extends parallel to the surface including the D2 direction and the D3 direction.

[0076] The shape of the incident end 143a when viewed from the D1 direction is the same as the shape of the light emitting surface of the light source 123 when viewed from the same direction, for example, rectangular. The size on the surface of the incident end 143a including the D2 direction and the D3 direction can be the same as the size on the surface of the light emitting surface of the light source 123 including the D2 direction and the D3 direction, but is preferably appropriately larger than the size on the surface of the light emitting surface of the light source 123 including the D2 direction and the D3 direction. The exit end 143b corresponds to a third exit end and extends in parallel to the surface including the D2 direction and the D3 direction, and is larger than the incident end 143a. The shape of the exit end 143b when viewed from the D1 direction is the same as the shape of the modulation surface of the light modulating element 183 when viewed from the same direction, for example, rectangular. The size on the surface of the exit end 143b including the D2 direction and the D3 direction is equal to the size on the surface of the modulation surface of the light modulating element 183 including the D2 direction and the D3 direction. The side surface 143s and the reflection surface 143r connect the peripheral edge portion of the incident end 143a and the peripheral edge portion of the exit end 143b in the D1 direction.

[0077] The red light LR emitted from the light source 123 is incident on the light guide element 143 from the incident end 143a. In the light guide element 143, the region surrounded by the incident end 143a, the exit end 143b, and the reflection surface 143r is a region in which the red light LR propagates. The size on the surface including the D2 direction and the D3 direction of the region surrounded by the incident end 143a, the exit end 143b, and the reflection surface 143r increases as it advances from the +D1 side to the -D1 side in the D1 direction. Furthermore, the shape on the surface including the D2 direction and the D3 direction of the region surrounded by the incident end 143a, the exit end 143b, and the reflection surface 143r changes from the shape of the light emitting surface of the light source 123 when viewed from the D1 direction to the shape of the modulation surface of the light modulating element 183 as it advances from the +D1 side to the -D1 side.

[0078] The side surface 143s of the light guide element 143 and the reflection surface 143r provided to the side surface 143s as described later are at a prescribed angle with respect to an imaginary line orthogonal to the incident end 143a and the optical axis, and move away from the imaginary line on the surface including the D2 direction and the D3 direction as it moves from the +D1 side to the -D1 side. The red light LR incident on the light guide element 143 propagates from the +D1 side to the -D1 side within the region surrounded by the incident end 143a, the exit end 143b, and the reflection surface 143r.

[0079] In the case where the shape of the modulating surface of the light modulating element 183, as viewed in the D1 direction, is a long rectangle, the shape of the light emitting surface of the light source 123, as viewed in the D1 direction, is a long rectangle in a substantially similar relationship to the modulating surface of the light modulating element 183. In this case, the prescribed angle a, i.e., the taper angle, which the side surface 143s including the short side of the long rectangle and the reflecting surface 143r make with respect to the above-mentioned imaginary line and the optical axis, is preferably in the range of 7° to 22°. The prescribed angle β, i.e., the taper angle, which the side surface 143s including the long side of the long rectangle and the reflecting surface 143r make with respect to the above-mentioned imaginary line and the optical axis, is preferably in the range of 14° to 36°. The preferable ranges of the angles a, β are confirmed by numerical simulation based on the structure of the red light emitting portion 103 and light ray tracing.

[0080] A part of the red light LR incident to the light guide element 143 propagates in a direction making an angle smaller than the prescribed angle with respect to the imaginary line and the optical axis, does not incident to the reflecting surface 143r at all, and directly propagates from the incident end 143a to the emitting end 143b. The remaining part of the red light LR incident to the light guide element 143 makes an angle equal to or larger than the prescribed angle with respect to the imaginary line and the optical axis, is incident to the reflecting surface 143r from the incident end 143a one or more times, and reaches the emitting end 143b after being reflected by the reflecting surface 143r. The paths of the light rays of the red light LR in the region surrounded by the incident end 143a, the emitting end 143b, and the reflecting surface 143r differ depending on the incident angle to the incident end 143a, and involve a plurality of paths in which the number of times of reflection at the reflecting surface 143r differs from each other. Thus, the illuminance distribution of the red light LR propagating in the region surrounded by the incident end 143a, the emitting end 143b, and the reflecting surface 143r is homogenized in the plane including the D2 direction and the D3 direction. That is, the light guide element 143 homogenizes the illuminance distribution of the incident red light LR in the plane including the D2 direction and the D3 direction. The red light LR whose illuminance distribution is homogenized is emitted from the emitting end 143b toward the -D1 side.

[0081] The light guide element 143, like the light guide elements 141 and 142, is a hollow reflector constituted by, for example, a plate-shaped member constituted by a transparent material such as optical glass. The end portion of the frame of the light guide element 143 on the +D1 side, as viewed in the D1 direction, has the same shape and size as the incident end 143a and the light emitting surface of the light source 123, and is formed, for example, in a rectangular frame shape. The end of the frame of the light guide element 143 on the -D1 side has the same shape and size as the emitting end 143b and the modulating surface of the light modulating element 183, and is formed, for example, in a rectangular frame shape different in size from the end on the +D1 side.

[0082] The light guide member 143 is configured by connecting edges of waists of four plate-like members having a trapezoidal shape to each other. The length of the edge on the +D1 side parallel to the D2 direction or the D3 direction, which corresponds to the upper base of the four plate-like members, is set according to the size in the D2 direction or the D3 direction of the light emitting surface of the light source 123 and the incident end 143a. The length of the edge on the -D1 side parallel to the D2 direction or the D3 direction, which corresponds to the lower base of the four plate-like members, is set according to the size in the D2 direction or the D3 direction of the modulation surface of the light modulation member 183 and the emission end 143b.

[0083] In the light guide member 143, in order to increase the reflectance of the red light LR incident to the light guide member 143 from the incident end 143a in the vicinity of the side surface 143s, a reflection film 253 configured of a dielectric multilayer film or the like is provided on the plate surface of the plate-like member on the side opposite to the side surface 143s, that is, on the plate surface of the plate-like member facing the internal space of the light guide member 143. A part of the red light LR incident to the internal space of the light guide member 143 from the incident end 143a is reflected by the reflection film 253 and travels toward the -D1 direction.

[0084] The intensity of the red light LR reflected by the reflection film 253 sometimes depends on the incident angle of the red light LR incident to the reflection film 253. In the case where the reflection film 253 is configured of a dielectric multilayer film, for example, the incident angle dependence of the intensity of the red light LR emitted from the reflection film 253 changes depending on parameters such as the refractive indexes of the plurality of films included in the dielectric multilayer film, the thickness of the films, the number of the films, and the like. As described above, for example, in a range where the angle a is 7° to 22° and the angle β is 14° to 36°, the reflection film 253 is designed in such a manner that the incident angle of the red light LR having the highest intensity of the red light LR emitted from the reflection surface 143r and the reflection film 253 is in a range of 60° to 90°, and the parameters of the dielectric multilayer film are appropriately decided. The relationship between the incident angle of the red light LR to the reflection film 253 and the intensity of the red light LR emitted from the reflection film 253 is also obtained by numerical simulation based on the structure of the red light emission section 103 and ray tracing.

[0085] In addition, in the case where the light guide member 143 is configured of a plate-like member configured of a transparent member, and the plate surface of the plate-like member facing the external space of the light guide member 143 functions as the reflection surface 143r, a part of the red light LR incident to the internal space of the light guide member 143 from the incident end 143a is incident to the plate-like member from the plate surface of the plate-like member facing the internal space of the light guide member 143, is refracted, is reflected by the plate surface facing the external space of the light guide member 143, propagates again in the plate-like member, is refracted by the plate surface facing the internal space of the light guide member 143, is emitted to the internal space of the light guide member 143, and travels toward the -D1 direction.

[0086] The parallelizing element 163 is disposed on the optical path of the red light LR emitted from the light guide element 143, and is disposed at a position that overlaps the light guide element 143 in the D2 direction and the D3 direction on the -D1 side from the light guide element 143. The parallelizing element 163 corresponds to a third parallelizing element, and parallelizes the red light LR emitted from the light guide element 143 in the D1 direction.

[0087] The parallelizing element 163 is, for example, a plano-convex lens having an incident surface constituted by a flat surface orthogonal to the D1 direction and an emission surface constituted by a convex curved surface that protrudes toward the emission side of the red light LR. The focal point F3 of the plano-convex lens constituting the parallelizing element 163 is located at least on the +D1 side from the parallelizing element 163, and on the side opposite to the -D1 side from which the red light LR is emitted from the parallelizing element 163, and further on the +D1 side from the light guide element 143. The incident surface of the parallelizing element 163 is in contact with the emission end 143b of the light guide element 143. By bringing the parallelizing element 163 into contact with the emission end 143b, the red light LR emitted from the emission end 143b of the light guide element 143 is taken into the parallelizing element 163 to the maximum extent, and loss of the red light LR can be suppressed. However, the parallelizing element 163 can also be an optical lens other than a plano-convex lens that can parallelize the incident red light LR, and can be disposed at an appropriate interval from the light guide element 143 in the D1 direction.

[0088] The focal length f3 of the parallelizing element 163 is longer than the length g3 in the D1 direction from the incident end 143a to the emission end 143b of the light guide element 143. The focal length f3 of the parallelizing element 163 is, for example, preferably 1.1 times or more the length g3 of the light guide element 143, and more preferably 1.1 times or more the length g3 and 2.0 times or less the length g3. By setting the focal length f3 within the above range, the red light LR emitted from the light source 123 is efficiently parallelized, and the utilization efficiency of the red light LR is improved. The preferable range of the focal length f3 is confirmed by numerical simulation based on the structure of the red light emission portion 103 and ray tracing.

[0089] The incident-side polarization element 173 is disposed on the optical path of the red light LR emitted from the parallelizing element 163, and is disposed at a position that overlaps the parallelizing element 163 in the D2 direction and the D3 direction on the -D1 side from the parallelizing element 163. The incident-side polarization element 173 is, for example, in contact with the light modulation element 183 from the +D1 side, but can also be disposed at an appropriate interval from the light modulation element 183 in the D1 direction.

[0090] The incident-side polarizing element 173 corresponds to a 3rd polarizing element, and causes a predetermined polarized light in the red light LR emitted from the parallelizing element 163 to be emitted in the Dl direction toward the -Dl side. The predetermined polarized light corresponds to a 3rd polarizing component, and is, for example, an S-polarized light. The incident-side polarizing element 173 is, for example, a reflective polarizing plate or an absorptive polarizing plate having a plate surface parallel to a plane including the D2 direction and the D3 direction. Further, in a case where it is desired to suppress return light and stray light to an optical element in a front stage of the parallelizing element 161, it is preferable to employ an absorptive polarizing plate as the incident-side polarizing element 171. The incident-side polarizing element 173 transmits a portion of the incident red light LR including the predetermined polarized light toward the -Dl side, and reflects or absorbs another portion of the red light LR toward the +Dl side.

[0091] Further, the red light LR emitted from the light source 123 includes at least a P-polarized light and an S-polarized light, and is, for example, a random polarized light. The S-polarized component in the red light LR emitted from the light source 123 sequentially passes through the light guide element 143 and the parallelizing element 163, transmits the incident-side polarizing element 173, and is emitted toward the -Dl side of the incident-side polarizing element 173. The P-polarized component in the red light LR is the same as the S-polarized component, sequentially passes through the light guide element 143 and the parallelizing element 163, but is reflected or absorbed by the incident surface of the incident-side polarizing element 173, and is emitted toward the -Dl side of the incident-side polarizing element 173.

[0092] The light modulating element 183 is disposed on an optical path of the red light LR emitted from the incident-side polarizing element 173, and is disposed at a position overlapping the incident-side polarizing element 173 in the D2 direction and the D3 direction and on the -Dl side of the incident-side polarizing element 173. The light modulating element 183 corresponds to a 3rd light modulating element, and modulates the red light LR emitted from the incident-side polarizing element 173 in accordance with image information transmitted from an unillustrated computer or the like image forming apparatus connected to the light modulating element 183 from the outside.

[0093] The light modulating element 183 is, for example, a transmissive liquid crystal panel. The liquid crystal panel constituting the light modulating element 183 has a plurality of unillustrated pixels. Each pixel has a switching element. The switching element is, for example, a TFT. An electric signal corresponding to the luminance of the red light at the relative position of each pixel in the modulation surface of the light modulating element 183 in the image projected by the projector 301 is supplied to the switching element of each pixel. Each pixel modulates the vibration direction of the red light LR incident from the incident-side polarizing element 173 by the action of the switching element corresponding to the above-mentioned electric signal, and generates red image light IR. The image light IR corresponds to a 3rd light. The light modulating element 183 emits the image light IR generated by the liquid crystal panel in the Dl direction toward the -Dl side.

[0094] The emission-side polarizing element 177 is disposed on the optical path of the image light IR emitted from the light modulating element 183, and is disposed at a position overlapping the light modulating element 183 in the D2 direction and the D3 direction on the -D1 side of the light modulating element 183. The emission-side polarizing element 177 is, for example, in contact with the light modulating element 183 from the -D1 side, but can also be disposed at an appropriate interval from the light modulating element 183 in the D1 direction. The emission-side polarizing element 177 corresponds to the sixth polarizing element, and emits the prescribed polarized light in the image light IR emitted from the light modulating element 183 toward the -D1 side along the D1 direction. The prescribed polarized light corresponds to the sixth polarization component, and is, for example, P-polarized light.

[0095] The emission-side polarizing element 177 is, for example, a reflective-type polarizing plate or an absorptive-type polarizing plate having a plate surface parallel to the plane including the D2 direction and the D3 direction. In addition, in a case where it is desired to suppress return light and stray light to the light modulating element 183, it is preferable to employ an absorptive-type polarizing plate as the emission-side polarizing element 177. The emission-side polarizing element 177 transmits a portion of the incident image light IR including the prescribed polarized light toward the +D2 side, and reflects or absorbs another portion of the green light LG toward the -D2 side.

[0096] The light synthesizing element 200 is disposed at a region where the optical path of the blue image light IB emitted from the emission-side polarizing element 175, the optical path of the green image light IG emitted from the emission-side polarizing element 176, and the optical path of the red image light IR emitted from the emission-side polarizing element 177 intersect. The light synthesizing element 200 synthesizes the image lights IB, IG, IR emitted from the emission-side polarizing elements 175, 176, 177, and emits the synthesized light toward the +D2 side along the D2 direction.

[0097] The light synthesizing element 200 is, for example, a cross dichroic prism 210. The cross dichroic prism 210 has an incident surface 210c opposing the emission surface of the emission-side polarizing element 175, an incident surface 210d opposing the emission surface of the emission-side polarizing element 176, an incident surface 210e opposing the emission surface of the emission-side polarizing element 177, an emission surface 210b, and two reflecting films 211, 212. The incident surfaces 210c, 210e are parallel to the plane including the D2 direction and the D3 direction, and overlap each other in the D2 direction and the D3 direction. The incident surface 210d and the emission surface 210b are parallel to the plane including the D1 direction and the D3 direction, and overlap each other in the D1 direction and the D3 direction.

[0098] The reflective film 211 is arranged so as to move from the +D2 side to the -D2 side as moving from the -D1 side to the +D1 side when viewed in the D3 direction. The reflective film 212 is arranged so as to move from the -D2 side to the +D2 side as moving from the -D1 side to the +D1 side when viewed in the D3 direction. The reflective films 211, 212 overlap the incidence surfaces 210c, 210e in the D2 direction, and overlap the emission surface 210b and the incidence surface 210d in the D3 direction. The reflective film 211 reflects light of the blue wavelength band, and transmits light of the green wavelength band and the red wavelength band. The reflective film 212 reflects light of the red wavelength band, and transmits light of the blue wavelength band and the green wavelength band.

[0099] The cross dichroic prism 210 is configured by aligning the vertices of the right angles of the four right-angle prisms with the center position of the light synthesizing element 200 and adhering the right-angle constituent surfaces to each other when viewed in the D3 direction. The four right-angle prisms of the cross dichroic prism 210 are formed of a transparent material that transmits light of the visible wavelength band. The reflective film 211 is arranged on the right-angle constituent surface of the four right-angle prisms that moves from the +D2 side to the -D2 side as moving from the -D1 side to the +D1 side as described above, and is configured of, for example, a dielectric multilayer film. The reflective film 212 is arranged on the right-angle constituent surface of the four right-angle prisms that moves from the -D2 side to the +D2 side as moving from the -D1 side to the +D1 side as described above.

[0100] The P-polarized light of the blue image light IB emitted from the emission-side polarizing element 175 is incident on the inside of the cross dichroic prism 210 from the incidence surface 210c in the D1 direction toward the +D1 side, is transmitted through the reflective film 211, is reflected by the reflective film 212, and travels toward the +D2 side. The P-polarized light of the green image light IG emitted from the emission-side polarizing element 176 is incident on the inside of the cross dichroic prism 210 from the incidence surface 210d in the D2 direction toward the +D2 side, is transmitted through the reflective films 211, 212, and travels straight toward the +D2 side. The P-polarized light of the red image light IR emitted from the emission-side polarizing element 177 is incident on the inside of the cross dichroic prism 210 from the incidence surface 210e in the D1 direction toward the -D1 side, is transmitted through the reflective film 212, is reflected by the reflective film 211, and travels toward the +D2 side.

[0101] The image lights IB, IG, IR emitted from the reflective films 211, 212 of the cross dichroic prism 210 toward the +D2 side are synthesized with each other, and generate a full-color image light IM. The cross dichroic prism 210 emits the full-color image light IM from the emission surface 210b in the D2 direction toward the +D2 side.

[0102] The projection optical system 250 is disposed on an optical path of the image light IM emitted from the light synthesizing element 200. The projection optical system 250 projects the image light IM emitted from the projection optical system 250 to the screen SC disposed on the +D2 side, and enlarges and displays the image transmitted from the image forming device to the light modulating elements 181, 182, 183 on the screen SC.

[0103] The projection optical system 250 is constituted by, for example, one or more optical lenses arranged along the D2 direction. The optical lenses include, for example, a plano-convex lens, a plano-concave lens, a double convex lens, a double concave lens, a meniscus lens, an aspherical lens, a free-form surface lens, and the like.

[0104] Next, the structure of the main part of the color light emitting part will be described in detail, taking the green light emitting part 102 as an example. Figure 4 is an exploded perspective view of the light modulating element 182. The light modulating element 182 has the housing member 303, the counter substrate 312, the liquid crystal layer 314, the element substrate 316, the sealing material 318, and the cover member 302, which are sequentially stacked from the -D2 side toward the +D2 side along the D2 direction. In Figure 4 In the liquid crystal layer 314, the liquid crystal molecules are aligned in the D2 direction.

[0105] The housing member 303 and the cover member 302 are members for modularizing the light modulating element 182 as a liquid crystal panel, and constitute a mounting housing that sandwiches the counter substrate 312, the liquid crystal layer 314, and the element substrate 316 in the D2 direction. The housing member 303 and the cover member 302 function as a support member that supports the light modulating element 182. The housing member 303 and the cover member 302 correspond to the fixing member in the light modulating element 182.

[0106] The housing member 303 is formed in a frame shape on a surface including the D1 direction and the D3 direction. The housing member 303 is formed with a recess 304. The counter substrate 312 is housed in the recess 304 from the +D2 side. That is, the size on the surface including the D1 direction and the D3 direction and the depth in the D2 direction of the recess 304 are set to be equal to the size on the same surface and the thickness in the D2 direction of the counter substrate 312, so that the counter substrate 312 can be housed. An opening A305 is formed in a bottom wall of the recess 304 on the -D2 side. The size on the surface including the D1 direction and the D3 direction of the opening A305 is larger than the light beam region and the irradiation region of the S-polarized green light LGS emitted from the incident side polarizing element 172 and incident on the housing member 303 from the -D2 side.

[0107] The housing member 303 is provided with a protrusion 306. The protrusion 306 extends in the D3 direction along the side end in the D1 direction of the housing member 303, and at least a part of the side end in the D1 direction of the housing member 303 extends in the D3 direction. The inner wall surface of the protrusion 306 is located at least at a position further outward than the opening A305, and in the present embodiment, at a position further outward than the inner wall surface of the recess 304, when viewed in the D2 direction. The size of the region partially surrounded by the inner wall surface of the protrusion 306 when viewed in the D2 direction is set to be equal to the size in the face of the element substrate 316 containing the D1 direction and the D3 direction. The height of the protrusion 306 in the D2 direction is set to be equal to the thickness of the element substrate 316 in the D2 direction. In the face containing the D1 direction and the D3 direction, the element substrate 316 is supported to the inner wall surface of the protrusion 306.

[0108] The outer wall surface of the housing member 303, which extends in the D2 direction and the D3 direction along the side end in the D1 direction, is formed with a locking portion. The housing member 303 is formed of a member capable of reflecting green light LGS, such as a metal such as aluminum (Al) or stainless steel (SUS).

[0109] The cover member 302 is a plate-shaped member formed in a frame shape in the face containing the D1 direction and the D3 direction. The cover member 302 is formed with an opening A308. The size in the face of the opening A308 is larger than the light beam region and the irradiation region of the green light LGS emitted from the element substrate 316 and incident from the -D2 side as described below.

[0110] The outer periphery of the cover member 302, which extends in the D3 direction along the side end in the D1 direction, is formed with a locking portion protruding toward the -D2 side. The locking portion of the cover member 302 is locked from the +D2 side to the locking portion formed in the housing member 303. Thus, the cover member 302 can be detached with respect to the housing member 303. The cover member 302 is configured of the same member as the housing member 303, such as a metal such as Al or SUS.

[0111] Figure 5 is a cross-sectional view of the light modulating element 182, and is a view when cut along the face containing the D1 direction and the D2 direction. As shown in Figure 5 The light modulating element 182 is divided into a display region R1, a peripheral region R2, and a sealing region R3 from the center side toward the outer periphery side in a direction parallel to the face containing the D1 direction and the D3 direction, that is, the incident face of the green light LGS.

[0112] The opposing substrate 312 extends in a region inside a plane including the D1 direction and the D3 direction, as compared to at least an outer periphery of the display region R1, the peripheral region R2, and the sealing region R3. The liquid crystal layer 314 is disposed in the display region R1 and the peripheral region R2. Further, the liquid crystal layer 314 can also extend in a region inside a plane including the D1 direction and the D3 direction, as compared to at least an outer periphery of the display region R1 and the peripheral region R2. The element substrate 316 cooperates with the housing member 303 and the cover member 302 described above to be formed larger than the opposing substrate 312 in a plane including the D1 direction and the D3 direction. The element substrate 316 extends in the display region R1, the peripheral region R2, and the sealing region R3. The sealing material 318 extends in the peripheral region R2 and the sealing region R3, extends in a region outside the liquid crystal layer 314 in a plane including the D1 direction and the D3 direction, and seals the liquid crystal layer 314.

[0113] A plurality of pixels of the light modulating element 182 are formed in the display region R1. In other words, the display region R1 is a region in which a plurality of pixels are disposed, and is a region that converts the incident green light LGS into the image light IG. The display region R1 is divided into a plurality of pixel regions R11 and a plurality of inter-pixel regions R12 in a direction parallel to a plane including the D1 direction and the D3 direction. Each pixel region R11 corresponds to an opening portion, and is a region in which each pixel is formed. Each inter-pixel region R12 is a region that intervenes between pixel regions R11, R11 adjacent to each other in a direction parallel to a plane including the D1 direction and the D3 direction. A region RX occupied by one pixel and a storage unit is a region between centers of inter-pixel regions R12 adjacent to each other in a plane including the D1 direction and the D3 direction.

[0114] A microlens 402 is disposed in each pixel region R11 of the opposing substrate 312. The microlens 402 is formed of a material that is transparent to the green light LG, and causes the green light LGS that has transmitted the incident side polarizing element 172 to converge in a plane including the D1 direction and the D3 direction and to transmit toward the +D2 side. The microlens 402 is, for example, a plano-convex lens having an incident surface composed of a curved surface that projects toward the -D2 side and an emission surface composed of a flat surface parallel to the D1 direction and the D3 direction, but can be an optical lens other than a plano-convex lens as long as it can converge the green light LGS as described above.

[0115] A metal layer 411 and a support layer 412 are provided in each inter-pixel region R12 of the opposing substrate 312. The metal layer 411 is a reflection layer in which the green light LGS incident from the -D2 side into the inter-pixel region R12 is incident at the first stage, and is formed of a material capable of reflecting the green light LG. The metal constituting the metal layer 411 is, for example, an alloy of Al, and is the same metal as the conductive layer constituting each electrode provided in the element substrate 316.

[0116] The support layer 412 is formed on the +D2 side of the metal layer 411, is laminated on the +D2 side of the metal layer 411, and overlaps the metal layer 411 in the D1 direction and the D3 direction. The support layer 412 is provided as a base of the metal layer 411, but can be omitted in a case where the metal layer 411 can be separately configured. The material of the support layer 412 is, for example, titanium nitride (TiN), and can be the same as the material of a layer constituting a base of each electrode provided on the device substrate 316 or the material of a contact plug connecting electrodes to each other in the D2 direction.

[0117] A transparent electrode for aligning liquid crystals of the liquid crystal layer 314 is provided in each pixel region R11 of the device substrate 316. The detailed structure of the laminated structure is the same as that of a publicly known electro-optical device or semiconductor device.

[0118] A conductive layer 415 and a support layer 416 are provided in each inter-pixel region R12 of the device substrate 316. The conductive layer 415 constitutes a word line, a bit line, or a common line provided on the -D2 side of the word line or the bit line, or the like, for supplying a drive voltage to a switching element or the like formed in the pixel region R11. The conductive layer 415 also functions as a contact plug for connecting the various lines to each other in the D2 direction. The plurality of conductive layers 415 include a laminated structure of layers having conductivity, which is omitted from the illustration, constituting a TFT as the aforementioned switching element. The material of the conductive layer 415 is, for example, an alloy of Al or tungsten (W).

[0119] The support layer 416 is provided as a base of the conductive layer 415 and supports the conductive layer 415 in the D2 direction. The material of the support layer 416 is a conductive material excellent in fine hardness, planarity, and thermal stability, and is, for example, TiN.

[0120] In a plane including the D1 direction and the D3 direction, the width of the metal layer 411 and the support layer 412 of the opposing substrate 312 is at least equal to the width of the conductive layer 415 and the support layer 416 of the device substrate 316 and is smaller than the width of the conductive layer 415 and the support layer 416 of the device substrate 316. By making the width of the metal layer 411 and the support layer 412 equal to or smaller than the width of the conductive layer 415 and the support layer 416, the green light LGS incident on the pixel region R11 of the device substrate 316 is not blocked, and reduction in the utilization efficiency of the green light LG can be suppressed. Furthermore, the closer the width of the metal layer 411 and the support layer 412 to the width of the conductive layer 415 and the support layer 416, the more the amount of the green light LGS reflected to the -D2 side by the metal layer 411 can be ensured.

[0121] The same layer configuration as the display region Rl, an electrode configuration, and the like, which are not shown, are provided in the peripheral region R2 of the counter substrate 312 and the element substrate 316. In addition, the omitted metal layer 411, the conductive layer 415, or the support layer 412, 416, which are not shown, provided in the peripheral region R2 do not contribute to the conversion of the green light LGS and the generation of the image light IG. The green light LGS is converted into the image light IG by the liquid crystal layer 314 of the pixel, that is, the storage unit, which is disposed in each region RX of the display region Rl. Therefore, the size on the face including the Dl direction and the D3 direction of the display region Rl is set according to the size required for the image light IM before being enlarged and projected from the projector 301.

[0122] Figure 6 is a plan view of the light modulating element 182, and is a view of the case where the light modulating element 182 is observed in the D2 direction from the -D2 side on which the green light LG is incident. As shown in Figure 6 the plate surface 312a of the -D2 side of the counter substrate 312 is exposed at the opening A305 formed in the housing member 303. The plate surface 312a corresponds to the first face of the counter substrate 312 of the light modulating element 182.

[0123] In the light modulating element 182, the display region Rl in which the green light LGS is converted into the image light IG is located at a position more inward than the opening A305 formed in the housing member 303 on a face perpendicular to the D2 direction and including the Dl direction and the D3 direction. In a direction parallel to the face including the Dl direction and the D3 direction, a region more outward than the display region Rl and more inward than the opening A305 is a separation region R21.

[0124] The separation region R21 is provided in consideration of manufacturing errors of the housing member 303 and the cover member 302 in such a manner that the end portion of the housing member 303 constituting the edge of the opening A305 and the end portion of the cover member 302 constituting the edge of the opening A308 are not located more inward than the display region Rl. Therefore, the size in the Dl direction and the D3 direction of the separation region R21 is set to a size slightly larger than the manufacturing errors of the housing member 303 and the cover member 302. When viewed in the D2 direction, the separation region R21 includes at least the inner side of the peripheral region R2 in the face including the Dl direction and the D3 direction.

[0125] In the light modulating element 182, the green light LGS emitted from the incident side polarizing element 172 to the +D2 side is appropriately radiated outward than the opening A305 formed in the housing member 303 on a face including the Dl direction and the D3 direction. A region in which the green light LGS incident more outward than the opening A305 is an edge region R31.

[0126] The edge area R31 includes, when viewed from the D2 direction, an area in the peripheral area R2 that is outside the division area R21, and can also include an area inside at least a portion of the sealing area R3. In addition, the size of the emission end 142b of the light guide element 142 in the plane including the D1 direction and the D3 direction is set to be the same as the size of the area in the same plane that is occupied by the display area R1, the division area R21, and the edge area R31 of the light modulation element 182, and that is the area in which the green light LGS is incident.

[0127] In the housing member 303, a surface 303a parallel to the plane including the D1 direction and the D3 direction on the -D2 side is divided into the edge area R31 and an optical shielding area R32 that is outside the edge area R31. The surface 303a corresponds to the first surface of the housing member 303 of the light modulation element 182. As described above, the housing member 303 is formed of a member that reflects the green light LGS incident from the -D2 side toward the -D2 side. An optical shielding layer 320 that optically shields or absorbs the green light LGS is provided on the surface 303a of the optical shielding area R32. By providing the optical shielding layer 320 in the optical shielding area R32, even if the green light LG emitted from the light guide element 142 and the green light LGS emitted from the incident-side polarization element 172 are incident on the optical shielding area R32 that is outside the edge area R31 by chance, stray light generated by the green light LGS reflected by the surface 303a of the optical shielding area R32 can be suppressed.

[0128] The green light LGS incident on the display area R1 of the light modulation element 182 from the -D2 side along the D2 direction is reflected toward the -D2 side by the metal layer 411 of the plurality of inter-pixel areas R12 of the opposing substrate 312. If a metal layer including the metal layer 411 is provided in the peripheral area R2 of the opposing substrate 312, the green light LGS incident on the division area R21 of the light modulation element 182 from the -D2 side along the D2 direction is reflected toward the -D2 side by the metal layer including the metal layer 411. The green light LGS incident on the edge area R31 of the light modulation element 182 from the -D2 side along the D2 direction is reflected toward the -D2 side by the surface 303a of the housing member 303.

[0129] The green light LGS reflected toward the -D2 side from the light modulation element 182 as described above passes through the incident-side polarization element 172 and is incident on the light guide element 142, and, like the green light LGP reflected toward the -D2 side by the incident-side polarization element 172, propagates toward the -D2 side in the light guide element 142. That is, the green light LGS reflected toward the -D2 side from the light modulation element 182 and the green light LGS reflected toward the -D2 side by the incident-side polarization element 172 are incident on the light guide element 142 from the same direction, and propagate toward the -D2 side in the light guide element 142. Figure 3The green light LGP shown is likewise incident again to the phosphor 124 of the light source 122, contributing to excitation and light emission of the phosphor 124. As a result, the utilization efficiency of the green light LG in the green light emitting portion 102 and the projector 301 is improved.

[0130] The metal layer 411 of the opposing substrate 312 of the light modulating element 182 and the housing member 303 of the edge region R31 constitute a reflection portion 450 that reflects the green light LGS incident from the -D2 side in the D2 direction toward the -D2 side.

[0131] The projector 301 of the present embodiment described above has a light source (second light source) 121, a light source (first light source) 122, a light source (third light source) 123, a light guide member (second light guide member) 141, a light guide member (first light guide member) 142, a light guide member (third light guide member) 143, a parallelization member (second parallelization member) 161, a parallelization member (first parallelization member) 162, a parallelization member (third parallelization member) 163, a light modulation member (second light modulation member) 181, a light modulation member (first light modulation member) 182, a light modulation member (third light modulation member) 183, a light synthesis member 200, and a projection optical system 250. The light source 122 emits green light (first light) LG of a green wavelength band (first wavelength band). The light source 121 emits blue light (second light) LB of a blue wavelength band (second wavelength band) different from the green wavelength band. The light source 123 emits red light (third light) LR of a red wavelength band (third wavelength band) different from the blue wavelength band and the green wavelength band. The light guide member 142 has an incident end (first incident end) 142a for the green light LG emitted from the light source 122 to be incident and an emission end (first emission end) 142b for the green light LG to be emitted, and homogenizes the illuminance (in-plane illuminance) in the plane of the green light LG including the Dl direction and the D3 direction. The light guide member 141 has an incident end (second incident end) 141a for the blue light LB emitted from the light source 121 to be incident and an emission end (second emission end) 141b for the blue light LB to be emitted, and homogenizes the illuminance (in-plane illuminance) in the plane of the blue light LB including the D2 direction and the D3 direction. The light guide member 143 has an incident end (third incident end) 143a for the red light LR emitted from the light source 123 to be incident and an emission end (third emission end) 143b for the red light LR to be emitted, and homogenizes the illuminance (in-plane illuminance) in the plane of the red light LR including the Dl direction and the D3 direction. The light modulation member (first light modulation member) 182 modulates the green light LG emitted from the parallelization member 162 in accordance with image information. The light modulation member (second light modulation member) 181 modulates the blue light LB emitted from the parallelization member 161 in accordance with image information. The light modulation member (third light modulation member) 183 modulates the red light LR emitted from the parallelization member 163 in accordance with image information. The light synthesis member 200 synthesizes the image light (first light) IG emitted from the light modulation member 182, the image light (second light) IB emitted from the light modulation member 181, and the image light (third light) IR emitted from the light modulation member 183, and emits the image light (light) IM. The projection optical system 250 projects the image light (light) IM emitted from the light synthesis member 200.

[0132] In the projector 301 of the present embodiment, the light of the three colors of light, i.e., the blue light LB, the green light LG, and the red light LR, emitted from the light sources 121, 122, 123 is directly converted into the image lights IB, IG, IR by the light modulating elements 181, 182, 183, the image lights IB, IG, IR are synthesized by the light synthesizing element 200, and the generated full-color image light IM is projected. On the other hand, in the conventional projector, a white light is generated, the white light is separated into three color lights by a color separating element or a color separating optical system, each color light is converted into an image light by a light modulating element, and the image lights are synthesized into a full-color image light by a light synthesizing element, and the full-color image light is projected. In the projector 301 of the present embodiment, at the stage preceding the light modulating elements corresponding to the three color lights, a color synthesizing element or a color synthesizing optical system that synthesizes the three color lights into a white light and a color separating element or a color separating optical system that separates the white light into the three color lights can not be provided, and thus, as compared with the conventional projector, the number of components, the number of devices, and the size can be suppressed. According to the projector 301 of the present embodiment, as compared with the conventional projector, the size can be reduced.

[0133] In the projector 301 of the present embodiment, in the light modulating element 182, the side of the plate surface (the first surface) 312a of the opposing substrate 312 on which the green light (the first light) LGS is incident in the D2 direction and the pixel inter-region (region) R12 outside the pixel region (opening) R11 of the display region R1 in the direction parallel to the surface including the D1 direction and the D3 direction is provided with the metal layer 411 as the reflecting portion 450.

[0134] In the projector 301 of the present embodiment, the green light LGS that is emitted from the light guide element 142 and is incident to the display region R1 of the light modulating element 182 is reflected toward the light guide element 142 by the metal layer 411 of the display region R1 as the reflecting portion 450, is guided again by the light guide element 142, is incident to the phosphor 124 of the light source 122, and is used again for the emission of the green light LG. According to the projector 301 of the present embodiment, the utilization efficiency of the green light LG can be improved.

[0135] In the projector 301 of the present embodiment, for example, in the case where the housing member 303 of the light modulating element 182 is formed of a member that does not reflect the green light LG, or in the case where the surface 303a of the edge region R31 of the housing member 303 is also provided with the light shielding layer 320, the reflecting portion 450 is composed only of the metal layer 411 of the display region R1. In this case, according to the projector 301 of the present embodiment, an improvement in the utilization efficiency of the green light LG can also be expected.

[0136] In the projector 301 of this embodiment, the light modulating element 182 has a reflection portion 450 on the outer side of the display region Rl in the D2 direction on the side of the plate surface (first surface) 312a of the opposing substrate 312 of the green light (first light) LGS incident, the surface (first surface) 303a of the housing member 303, and in a direction parallel to the surface including the Dl direction and the D3 direction. The reflection portion 450 on the outer side of the display region Rl is constituted by, for example, the surface 303a of the edge region R31 of the housing member 303 formed of metal. In addition, in the case where the metal layer is provided in the separation region R21 in the peripheral region R2 of the opposing substrate 312 of the light modulating element 182, the reflection portion 450 on the outer side of the display region Rl also includes, for example, the metal layer of the separation region R21.

[0137] In the projector 301 of this embodiment, the green light LGS incident on the display region Rl of the light modulating element 182 from the light guide element 142 is reflected toward the light guide element 142 by the reflection layer of the separation region R21 and the housing member 303 as the reflection portion 450, guided again by the light guide element 142, incident on the phosphor 124 of the light source 122, and used again for the emission of the green light LG. According to the projector 301 of this embodiment, it is possible to improve the utilization efficiency of the green light LG.

[0138] In the projector 301 of this embodiment, for example, in the case where the conductive layer 415 or other metal layer that reflects the green light LG is not provided in the display region Rl of the opposing substrate 312 of the light modulating element 182, the reflection portion 450 is constituted only by the housing member 303 on the outer side of the display region Rl. In this case, according to the projector 301 of this embodiment, it is also possible to expect an improvement in the utilization efficiency of the green light LG.

[0139] In the projector 301 of this embodiment, the reflection portion 450 is provided between the separation region (light incident region) R21 and the edge region (light incident region) R31 from the display region Rl to which the green light LGS is incident. The surface 303a between the outer side of the edge region R31 of the housing member 303 and the outer peripheral end portion (end portion) on the surface including the Dl direction and the D3 direction of the light modulating element 182 is provided with the light shielding layer (light shielding portion) 320.

[0140] In the projector 301 of this embodiment, the green light LGS that has exited from the light guide element 142 and has been incident on the display region R1 of the light modulating element 182 is reflected toward the light guide element 142 by the metal layer of the partition region R21 of the opposing substrate 312 and the housing member 303 of the edge region R31, and is incident on the phosphor 124 of the light source 122 to be used again for the emission of the green light LG. According to the projector 301 of this embodiment, it is possible to improve the utilization efficiency of the green light LG. In addition, in the projector 301 of this embodiment, the green light LGS that has been incident on the light-shielding region R32 outside the edge region R31 is shielded by the light-shielding layer 320. According to the projector 301 of this embodiment, it is possible to suppress the generation of stray light caused by the green light LGS that has been incident on the light-shielding region R32.

[0141] In the projector 301 of this embodiment, the reflection portion 450 is provided at a portion (partition portion) of the partition region R21 of the opposing substrate (substrate) 312 on the side of the plate surface (first surface) 312a of the light modulating element 182.

[0142] In the projector 301 of this embodiment, the green light LGS that has exited from the light guide element 142 and has been incident on the display region R1 of the light modulating element 182 is reflected toward the light guide element 142 by the metal layer 411 of the partition region R21 of the opposing substrate 312 or a structural element formed of a material capable of reflecting the green light LGS other than the metal layer 411, and is incident on the phosphor 124 of the light source 122 to be used again for the emission of the green light LG. According to the projector 301 of this embodiment, it is possible to improve the utilization efficiency of the green light LG. In addition, according to the projector 301 of this embodiment, since the partition region R21 is provided, it is possible to allow the manufacturing error of the housing member 303 and the cover member 302.

[0143] In the projector 301 of this embodiment, the reflection portion 450 is provided at the housing member (fixing member) 303 that supports the opposing substrate 312, the liquid crystal layer 314, the sealing material 318, and the element substrate 316 in the D2 direction in cooperation with the cover member 302 in the light modulating element 182.

[0144] In the projector 301 of this embodiment, the green light LGS that has exited from the light guide element 142 and has been incident on the display region R1 of the light modulating element 182 is reflected toward the light guide element 142 by the housing member 303, and is incident on the phosphor 124 of the light source 122 to be used again for the emission of the green light LG. According to the projector 301 of this embodiment, it is possible to improve the utilization efficiency of the green light LG.

[0145] In the projector 301 of this embodiment, the reflection portion 450 is provided on the metal layer 411 of the counter substrate (substrate) 312 that overlaps the conductive layer (wiring layer) 415 formed around the pixel region (opening portion) R11 in a direction parallel to a plane including the D1 direction and the D3 direction in plan view.

[0146] In the projector 301 of this embodiment, the green light LGS incident to the counter substrate 312, the liquid crystal layer 314, and the element substrate 316 of the pixel region R11 is not blocked by the metal layer 411 of the reflection portion 450, and the utilization efficiency of the green light LG can be further improved.

[0147] In the projector 301 of this embodiment, the focal length f2 of the parallelizing element 162 is longer than the length g2 from the incident end 142a to the exit end 142b of the light guide element 142. The focal length f1 of the parallelizing element 161 is longer than the length g1 from the incident end 141a to the exit end 141b of the light guide element 141. The focal length f3 of the parallelizing element 163 is longer than the length g3 from the incident end 143a to the exit end 143b of the light guide element 143.

[0148] In the projector 301 of this embodiment, in a 3-plate type projector, the large-scale of the blue light exit portion 101, the green light exit portion 102, and the red light exit portion 103 can be suppressed. According to the projector 301 of this embodiment, the miniaturization of the entire device can be achieved.

[0149] In the projector 301 of this embodiment, the light source 122 has an LED main body (light emitting body) 125 and a phosphor 124 that emits green light LG as fluorescent light using blue light (excitation light) emitted from the LED main body 125.

[0150] In the projector 301 of this embodiment, the green light LGS reflected by the reflection portion 450 of the light modulating element 182 is incident again to the phosphor 124 from the +D2 side for re-excitation of the phosphor 124. According to the projector 301 of this embodiment, the utilization efficiency of the green light LG can be further improved.

[0151] In the projector 301 of this embodiment, the cross-sectional shape of the light guide elements 141 and 143 perpendicular to the optical axis and the D1 direction is rectangular, and the cross-sectional shape of the light guide element 142 perpendicular to the optical axis and the D2 direction is rectangular.

[0152] In the projector 301 of this embodiment, the blue light LB, the green light LG, and the red light LR, which are rectangular in shape and uniform in illuminance, can be easily generated in planes perpendicular to the optical axes of the color lights by the light guide elements 141, 142, 143. According to the projector 301 of this embodiment, color lights corresponding to the rectangular modulation planes of the light modulation elements 181, 182, 183 can be easily generated.

[0153] The projector 301 of this embodiment further includes an incident-side polarizing element (2nd polarizing element) 171, an incident-side polarizing element (1st polarizing element) 172, and an incident-side polarizing element (3rd polarizing element) 173. The incident-side polarizing element 171 is disposed between the parallelizing element 161 and the light modulation element 181, transmits a part of the blue light LB having an S-polarization component (2nd polarization component), and reflects another part of the blue light LB, i.e., a P-polarization component. The incident-side polarizing element 172 is disposed between the parallelizing element 162 and the light modulation element 182, transmits a part of the green light LG having an S-polarization component (1st polarization component), and reflects another part of the green light LG, i.e., a P-polarization component. The incident-side polarizing element 173 is disposed between the parallelizing element 163 and the light modulation element 183, transmits a part of the red light LR having an S-polarization component (3rd polarization component), and reflects another part of the red light LR, i.e., a P-polarization component. In the projector 301 of this embodiment, another part of the blue light LB is incident on the light guide element 141 toward the light source 121. Another part of the green light LG is incident on the light guide element 142 toward the light source 122. Another part of the red light LR is incident on the light guide element 143 toward the light source 123.

[0154] In the projector 301 of this embodiment, the other portions of the blue light LB, the green light LG, and the red light LR, which are each reflected by the incident-side polarizing elements 171, 172, 173 and emitted from the incident-side polarizing elements 171, 172, 173, are incident on the light sources 121, 122, 123. In the light sources 121, 122, 123, for example, the light source 122 has the phosphor 124, and thus the other portion of the green light LG directed toward the light source 122 is incident on the phosphor 124, which contributes to excitation of the phosphor 124. Further, in the case where the substrates 111, 112, 113 of the light sources 121, 122, 123 are reflective, the other portions of the blue light LB, the green light LG, and the red light LR, which are each directed toward the light sources 121, 122, 123, are reflected by the substrates 111, 112, 113 and incident on the light guide elements 141, 142, 143 again to be utilized. According to the projector 301 of this embodiment, the other portions of the blue light LB, the green light LG, and the red light LR, which are each reflected by the incident-side polarizing elements 171, 172, 173, are incident on the light guide elements 141, 142, 143 again, and thus it is possible to improve the utilization efficiency of the blue light LB, the green light LG, and the red light LR.

[0155] In the projector 301 of this embodiment, the cross-sectional area of the emission end 141b of the light guide element 141 including the D2 direction and the D3 direction is larger than the cross-sectional area of the incident end 141a of the light guide element 141 including the same directions. The cross-sectional area of the emission end 142b of the light guide element 142 including the D1 direction and the D3 direction is larger than the cross-sectional area of the incident end 142a of the light guide element 142 including the same directions. The cross-sectional area of the emission end 143b of the light guide element 143 including the D2 direction and the D3 direction is larger than the cross-sectional area of the incident end 143a of the light guide element 143 including the same directions.

[0156] In the projector 301 of this embodiment, the illuminance distribution of the blue light LB, the green light LG, and the red light LR is uniformized and the irradiation area of each color light is enlarged before being incident on the incident ends 141a, 142a, 143a of the light guide elements 141, 142, 143 and emitted from the emission ends 141b, 142b, 143b. According to the projector 301 of this embodiment, it is possible to easily enlarge the size in a plane perpendicular to the optical axis, i.e., the irradiation area, of the blue light LB, the green light LG, and the red light LR emitted from the light sources 121, 122, 123, each of which has a smaller light emitting surface than the modulation surface of each of the light modulation elements 181, 182, 183, in correspondence with the modulation surface of each of the light modulation elements 181, 182, 183.

[0157] In the projector 301 of this embodiment, the light guide elements 141, 142, 143 are composed of glass such as optical glass or metal.

[0158] In the projector 301 of the present embodiment, as described above, the light guide members 141, 142, 143 are constituted by plate-shaped members composed of a transparent material including glass or the like. According to the projector 301 of the present embodiment, the heat dissipation and heat resistance of the light guide members 141, 142, 143 can be improved.

[0159] In addition, as a modification of the projector 301 of the present embodiment, the plate-shaped members constituting the light guide members 141, 142, 143 can also be composed of metal. That is, the light guide members 141, 142, 143 can also be constituted by plate-shaped members composed of metal that reflects blue light LB, green light LG, and red light LR, for example. In this case, as in the case where a reflective film is provided on the plate surface of the plate-shaped member composed of a transparent material that faces the internal space, the plate surface of the plate-shaped member that faces the internal space of the light guide members 141, 142, 143 functions as a reflecting surface 141r, 142r, 143r. A portion of the blue light LB, green light LG, and red light LR that has entered the internal space of the light guide members 141, 142, 143 from the entrance end 141a, 142a, 143a is reflected by the plate surface of the plate-shaped member that faces the internal space of the light guide members 141, 142, 143 and travels along the optical axis. In the modification of the projector 301 of the present embodiment as well, the heat dissipation and heat resistance of the light guide members 141, 142, 143 can be improved.

[0160] In the projector 301 of the present embodiment, the light guide members 141, 142, 143 are hollow, and a reflective film 251, 252, 253 is provided on a surface (inner surface) that faces the internal space of the plate-shaped member constituting the light guide members 141, 142, 143.

[0161] In the projector 301 of the present embodiment, a portion of the blue light LB, green light LG, and red light LR that has entered the light guide members 141, 142, 143 is specularly reflected by the reflective film 251, 252, 253 and propagates in the internal space of the light guide members 141, 142, 143. According to the projector 301 of the present embodiment, the loss of the blue light LB, green light LG, and red light LR inside the light guide members 141, 142, 143 can be reduced.

[0162] Further, as another modification of the projector 301 of the present embodiment, the light guide members 141, 142, 143 can be solid and made of a transparent material such as optical glass. In this case, the plate surfaces of the reflectors constituting the light guide members 141, 142, 143, i.e., the side surfaces 141s, 142s, 143s, function as the reflecting surfaces 141r, 142r, 143r. A portion of the blue light LB, the green light LG, and the red light LR, respectively, which is incident on the reflectors of the light guide members 141, 142, 143 from the incident ends 141a, 142a, 143a is totally reflected by the reflecting surfaces 141r, 142r, 143r toward the outside of the reflectors and travels along the optical axis. Further, the light guide members 141, 142, 143 are solid and made of a transparent material such as optical glass, and the reflecting films 251, 252, 253 can be provided on the side surfaces 141s, 142s, 143s. In the other modification of the projector 301 of the present embodiment, the loss of the blue light LB, the green light LG, and the red light LR inside the light guide members 141, 142, 143 can be reduced.

[0163] In the projector 301 of the present embodiment, the cross-sectional shape of the light guide members 141, 142, 143 is rectangular. When the inclination angle of the side surface of the light guide members 141, 142, 143 including the short side, i.e., the angle with respect to the optical axis is α, 7° ≤ α ≤ 22°. When the inclination angle of the side surface of the light guide members 141, 142, 143 including the long side is β, 14° ≤ β ≤ 36°. The reflecting films 251, 252, 253 are provided on the surface (inner side surface) of the hollow light guide members 141, 142, 143 facing the inside of the plate-like member. When the incident angle of the light incident on the reflecting films 251, 252, 253 at the time when the reflectivity of the blue light LB, the green light LG, and the red light LR, respectively, in the reflecting films 251, 252, 253 is the highest is θ in , 60° ≤ θ in ≤ 90°.

[0164] In the projector 301 of the present embodiment, the blue light LB, the green light LG, and the red light LR emitted from the light sources 121, 122, 123 are radiated toward the inside of the light guide members 141, 142, 143 at a predetermined angle with respect to the optical axis from the incident ends 141a, 142a, 143a. By designing the reflecting films 251, 252, 253 as described above, the intensities of the blue light LB, the green light LG, and the red light LR reflected by the reflecting films 251, 252, 253 are strong. According to the projector 301 of the present embodiment, the loss of the blue light LB, the green light LG, and the red light LR in the light guide members 141, 142, 143 can be reduced as much as possible, and the utilization efficiency of the blue light LB, the green light LG, and the red light LR can be improved.

[0165] The projector 301 of the present embodiment further has an emission side polarizing element (fifth polarizing element) 175, an emission side polarizing element (fourth polarizing element) 176, and an emission side polarizing element (sixth polarizing element) 177. The emission side polarizing element 175 is disposed between the light modulating element 181 and the light combining element 200, and transmits a portion of the image light (light) IB emitted from the light modulating element 181 having a P-polarization component (fifth polarization component), and absorbs another portion of the image light IB other than the P-polarization component. The emission side polarizing element 176 is disposed between the light modulating element 182 and the light combining element 200, and transmits a portion of the image light (light) IG emitted from the light modulating element 182 having a P-polarization component (fourth polarization component), and absorbs another portion of the image light IG other than the P-polarization component. The emission side polarizing element 177 is disposed between the light modulating element 183 and the light combining element 200, and transmits a portion of the image light (light) IR emitted from the light modulating element having a P-polarization component (sixth polarization component), and absorbs another portion of the image light IR other than the P-polarization component.

[0166] In the projector 301 of the present embodiment, by the emission side polarizing elements 175, 176, 177 composed of, for example, absorbing-type polarizing plates or polarizing elements, the P-polarization components in the image lights IB, IG, IR are made to be incident on the light combining element 200, and another portion of the image lights IB, IG, IR other than the P-polarization components is absorbed, and the return light and stray light of the light modulating elements 181, 182, 183 from another portion of the image lights IB, IG, IR can be suppressed.

[0167] The above-described preferred embodiments of the present application have been described in detail, but the present application is not limited to the specific embodiments, and various modifications and changes can be made within the scope of the present application as set forth in the claims.

[0168] For example, the LEDs that constitute the light sources 121, 123 in the blue light emission section 101 or the red light emission section 103 can also have phosphors that are excited by the excitation light emitted from the LED main bodies to emit blue light LB or red light LR, like the green light emission section 102. In addition, the LEDs of the light source 122 of the green light emission section 102 can also not have the phosphor 124, and the light source 122 can be composed of LEDs that directly emit green light LG. In addition, the polarization components that are transmitted by the incident side polarizing plates disposed in the light paths of the respective color lights can or can not be common components.

[0169] In addition, the projector of the above-described embodiments is a transmissive 3-plate type projector, but can also be a reflective 3-plate type projector.

[0170] [Summary of the Disclosure]

[0171] The following is a summary of the present disclosure.

[0172] (Paragraph 1) A projector having: a first light source that emits first light of a first wavelength band; a second light source that emits second light of a second wavelength band different from the first wavelength band; a third light source that emits third light of a third wavelength band different from the first wavelength band and the second wavelength band; a first light guide element having a first incident end for the first light emitted from the first light source to be incident and a first emission end for the first light to be emitted, the first light guide element homogenizing an in-plane illuminance of the first light; a second light guide element having a second incident end for the second light emitted from the second light source to be incident and a second emission end for the second light to be emitted, the second light guide element homogenizing an in-plane illuminance of the second light; a third light guide element having a third incident end for the third light emitted from the third light source to be incident and a third emission end for the third light to be emitted, the third light guide element homogenizing an in-plane illuminance of the third light; a first parallelization element that parallelizes the first light emitted from the first light guide element; a second parallelization element that parallelizes the second light emitted from the second light guide element; a third parallelization element that parallelizes the third light emitted from the third light guide element; a first light modulation element that modulates the first light emitted from the first parallelization element based on image information; a second light modulation element that modulates the second light emitted from the second parallelization element based on image information; a third light modulation element that modulates the third light emitted from the third parallelization element based on image information; a light synthesis element that synthesizes the first light emitted from the first light modulation element, the second light emitted from the second light modulation element, and the third light emitted from the third light modulation element to be emitted; and a projection optical system that projects the light emitted from the light synthesis element, a reflection portion being provided on a first surface side on which the first light is incident in the first light modulation element and on a region other than an opening portion of a display region.

[0173] According to the structure of Paragraph 1, optical members used for generating white light and optical members for separating light by each color light are not necessary, and thus the number of components is small, the large size of a 3-plate projector can be suppressed, and a small projector can be realized. In addition, according to the structure of Paragraph 1, the first light is reflected toward the first light source by the reflection portion of the first light modulation element, and the utilization efficiency of the first light can be improved.

[0174] (Auxiliary Note 2) A projector having: a first light source that emits first light of a first wavelength band; a second light source that emits second light of a second wavelength band different from the first wavelength band; a third light source that emits third light of a third wavelength band different from the first wavelength band and the second wavelength band; a first light guide element having a first incident end through which the first light emitted from the first light source is incident and a first emission end through which the first light is emitted, the first light guide element homogenizing an in-plane illuminance of the first light; a second light guide element having a second incident end through which the second light emitted from the second light source is incident and a second emission end through which the second light is emitted, the second light guide element homogenizing an in-plane illuminance of the second light; a third light guide element having a third incident end through which the third light emitted from the third light source is incident and a third emission end through which the third light is emitted, the third light guide element homogenizing an in-plane illuminance of the third light; a first parallelization element that parallelizes the first light emitted from the first light guide element; a second parallelization element that parallelizes the second light emitted from the second light guide element; a third parallelization element that parallelizes the third light emitted from the third light guide element; a first light modulation element that modulates the first light emitted from the first parallelization element based on image information; a second light modulation element that modulates the second light emitted from the second parallelization element based on image information; a third light modulation element that modulates the third light emitted from the third parallelization element based on image information; a light synthesizing element that synthesizes the first light emitted from the first light modulation element, the second light emitted from the second light modulation element, and the third light emitted from the third light modulation element and emits the synthesized light; and a projection optical system that projects the light emitted from the light synthesizing element, the first light modulation element having a reflection portion on a first surface side on which the first light is incident and outside of a display region.

[0175] According to the structure of the auxiliary note 2, the optical members used for generating white light and the optical members for separating light by each color light are not required, and thus the number of components is small, the enlargement of the 3-plate projector can be suppressed, and a small projector can be realized. In addition, according to the structure of the auxiliary note 2, the first light can be reflected toward the first light source by the reflection portion of the first light modulation element, and the utilization efficiency of the first light can be improved.

[0176] (Auxiliary Note 3) The projector according to the auxiliary note 1 or 2, the reflection portion is provided between the display region and a light incident region where the first light is incident, and a light shielding portion is provided between the outside of the light incident region and an end portion of the first light modulation element.

[0177] According to the structure of the supplementary note 3, the utilization efficiency of the first light reflected by the reflection portion can be improved, and the generation of stray light can be suppressed.

[0178] (Supplementary note 4) The projector according to any one of supplementary notes 1 to 3, wherein the reflection portion is provided to a partition portion of a substrate on the first face side of the first light modulating element.

[0179] According to the structure of the supplementary note 4, the utilization efficiency of the first light reflected at the partition portion of the first light modulating element can be improved, and the manufacturing error of the fixing member can be allowed.

[0180] (Supplementary note 5) The projector according to any one of supplementary notes 1 to 4, wherein the reflection portion is provided to a fixing member of the first light modulating element.

[0181] According to the structure of the supplementary note 5, the utilization efficiency of the first light reflected by the fixing member can be improved.

[0182] (Supplementary note 6) The projector according to any one of supplementary notes 1 to 5, wherein the reflection portion is provided to a metal layer of a substrate overlapping a wiring layer formed around an opening portion of the display region in plan view.

[0183] According to the structure of the supplementary note 6, the utilization efficiency of the first light can be improved without the metal layer of the reflection portion blocking the first light incident to the opening portion.

[0184] (Supplementary note 7) The projector according to any one of supplementary notes 1 to 6, wherein a focal length of the first parallelizing element is longer than a length from the first incident end to the first emission end, a focal length of the second parallelizing element is longer than a length from the second incident end to the second emission end, and a focal length of the third parallelizing element is longer than a length from the third incident end to the third emission end.

[0185] According to the structure of the supplementary note 7, the number of components and the size of the 3-plate type projector can be suppressed, and a small projector can be realized.

[0186] (Supplementary note 8) The projector according to any one of supplementary notes 1 to 7, wherein the first light source has: a light emitter; and a phosphor that emits the first light as phosphor light using excitation light emitted from the light emitter.

[0187] According to the structure of the supplementary note 8, the first light reflected by the reflection portion of the first light modulating element can be incident to the phosphor of the first light source, the phosphor can be re-excited, and the utilization efficiency of the first light can be improved.

[0188] (Paragraph 9) The projector according to any one of paragraphs 1 to 8, wherein the first light guide member has a rectangular cross-sectional shape, the second light guide member has a rectangular cross-sectional shape, and the third light guide member has a rectangular cross-sectional shape.

[0189] According to the structure of paragraph 9, it is possible to easily generate color lights corresponding to the rectangular modulation surfaces of the first, second, and third light modulation elements.

[0190] (Paragraph 10) The projector according to any one of paragraphs 1 to 9, further comprising: a first polarization element disposed between the first collimating element and the first light modulation element, which transmits a portion of the first light having a first polarization component and reflects the other portion; a second polarization element disposed between the second collimating element and the second light modulation element, which transmits a portion of the second light having a second polarization component and reflects the other portion; and a third polarization element disposed between the third collimating element and the third light modulation element, which transmits a portion of the third light having a third polarization component and reflects the other portion, wherein the other portion of the first light is incident on the first light guide member, the other portion of the second light is incident on the second light guide member, and the other portion of the third light is incident on the third light guide member.

[0191] According to the structure of paragraph 10, the first, second, and third lights reflected by the first, second, and third polarization elements are incident on the first, second, and third light guide members again, and it is possible to improve the utilization efficiency of the first, second, and third lights.

[0192] (Paragraph 11) The projector according to any one of paragraphs 1 to 10, wherein the cross-sectional area of the first exit end is larger than the cross-sectional area of the first entrance end, the cross-sectional area of the second exit end is larger than the cross-sectional area of the second entrance end, and the cross-sectional area of the third exit end is larger than the cross-sectional area of the third entrance end.

[0193] According to the structure of paragraph 11, it is possible to make the sizes of the irradiation regions of the first, second, and third lights emitted from the first, second, and third light sources coincide with the sizes of the modulation surfaces of the first, second, and third light modulation elements, and to make the illuminance distributions of the first, second, and third lights uniform and large.

[0194] (Paragraph 12) The projector according to any one of paragraphs 1 to 11, wherein the first light guide member, the second light guide member, and the third light guide member are made of glass or metal.

[0195] In the structure of the Note 12, heat dissipation and heat resistance of the first light guide element, the second light guide element, and the third light guide element can be improved.

[0196] (Note 13) The projector according to any one of the Notes 1 to 12, wherein the first light guide element, the second light guide element, and the third light guide element are hollow, and a reflection film is provided on inner side surfaces of the first light guide element, the second light guide element, and the third light guide element.

[0197] According to the structure of the Note 13, loss of the first light, the second light, and the third light generated in the first light guide element, the second light guide element, and the third light guide element can be suppressed, and utilization efficiency of the first light, the second light, and the third light can be improved.

[0198] (Note 14) The projector according to any one of the Notes 1 to 13, wherein a cross-sectional shape of the first light guide element is rectangular, a cross-sectional shape of the second light guide element is rectangular, a cross-sectional shape of the third light guide element is rectangular, a gradient angle of a side surface of the first light guide element, the second light guide element, and the third light guide element including a short side is a, and 7° ≤ a ≤ 22°, a gradient angle of a side surface of the first light guide element, the second light guide element, and the third light guide element including a long side is β, and 14° ≤ β ≤ 36°, a reflection film is provided on inner side surfaces of the first light guide element, the second light guide element, and the third light guide element, and an incident angle of light incident on the reflection film when reflectivity of the reflection film is the highest is θ, and 60° ≤ θ ≤ 90°. in in

[0199] According to the structure of the Note 14, loss of the first light, the second light, and the third light reflected in the first light guide element, the second light guide element, and the third light guide element and emitted from the first emission end, the second emission end, and the third emission end can be suppressed, and utilization efficiency of the first light, the second light, and the third light can be improved.

[0200] (Note 15) The projector according to any one of the Notes 1 to 14, further comprising: a fourth polarization element disposed between the first light modulation element and the light combining element, which transmits a part of light emitted from the first light modulation element having a fourth polarization component and absorbs the other part; a fifth polarization element disposed between the second light modulation element and the light combining element, which transmits a part of light emitted from the second light modulation element having a fifth polarization component and absorbs the other part; and a sixth polarization element disposed between the third light modulation element and the light combining element, which transmits a part of light emitted from the third light modulation element having a sixth polarization component and absorbs the other part.​​

[0201] According to the structure of the attached note 15, it is possible to make a part of the light emitted from the first light modulating element, the second light modulating element, and the third light modulating element, which has the fourth polarization component, the fifth polarization component, and the sixth polarization component, incident to the light synthesizing element, and by the fourth polarization element, the fifth polarization element, and the sixth polarization element absorbing the other part of the light emitted from the first light modulating element, the second light modulating element, and the third light modulating element, which is other than the fourth polarization component, the fifth polarization component, and the sixth polarization component, it is possible to suppress the return light and the stray light to the first light modulating element, the second light modulating element, and the third light modulating element caused by the other part than the fourth polarization component, the fifth polarization component, and the sixth polarization component.

Claims

1. A projector characterized by comprising: It has: a first light source which emits first light of a first wavelength band; a second light source which emits second light of a second wavelength band different from the first wavelength band; a third light source which emits third light of a third wavelength band different from the first wavelength band and the second wavelength band; a first light guide element which has a first incident end for the first light emitted from the first light source to be incident and a first emission end for emitting the first light, the first light guide element homogenizing the in-plane illuminance of the first light; a second light guide element which has a second incident end for the second light emitted from the second light source to be incident and a second emission end for emitting the second light, the second light guide element homogenizing the in-plane illuminance of the second light; a third light guide element which has a third incident end for the third light emitted from the third light source to be incident and a third emission end for emitting the third light, the third light guide element homogenizing the in-plane illuminance of the third light; a first parallelization element which parallelizes the first light emitted from the first light guide element; a second parallelization element which parallelizes the second light emitted from the second light guide element; a third parallelization element which parallelizes the third light emitted from the third light guide element; a first light modulation element which modulates the first light emitted from the first parallelization element based on image information; a second light modulation element which modulates the second light emitted from the second parallelization element based on image information; a third light modulation element which modulates the third light emitted from the third parallelization element based on image information; a light synthesis element which synthesizes the first light emitted from the first light modulation element, the second light emitted from the second light modulation element, and the third light emitted from the third light modulation element to be emitted; and a projection optical system which projects the light emitted from the light synthesis element, a reflection portion is provided on a first surface side on which the first light is incident in the first light modulation element and which is a region other than an opening portion of a display region.

2. A projector characterized by comprising: It has: a first light source which emits first light of a first wavelength band; a second light source which emits second light of a second wavelength band different from the first wavelength band; a third light source which emits third light of a third wavelength band different from the first wavelength band and the second wavelength band; a first light guide element which has a first incident end for the first light emitted from the first light source to be incident and a first emission end for emitting the first light, the first light guide element homogenizing the in-plane illuminance of the first light; a second light guide element which has a second incident end for the second light emitted from the second light source to be incident and a second emission end for emitting the second light, the second light guide element homogenizing the in-plane illuminance of the second light; a third light guide element having a third incident end for the third light emitted from the third light source to be incident thereon and a third emission end from which the third light is emitted, the third light guide element homogenizing an in-plane illuminance of the third light; a first parallelizing element which parallelizes the first light emitted from the first light guide element; a second parallelizing element which parallelizes the second light emitted from the second light guide element; a third parallelizing element which parallelizes the third light emitted from the third light guide element; a first light modulating element which modulates the first light emitted from the first parallelizing element based on image information; a second light modulating element which modulates the second light emitted from the second parallelizing element based on image information; a third light modulating element which modulates the third light emitted from the third parallelizing element based on image information; a light synthesizing element which synthesizes the first light emitted from the first light modulating element, the second light emitted from the second light modulating element, and the third light emitted from the third light modulating element to be emitted; and a projection optical system which projects the light emitted from the light synthesizing element, the first light modulating element has a reflection portion on a first surface side on which the first light is incident and outside of a display region.

3. The projector according to claim 1 or 2, wherein the reflection portion is provided between the display region and a light incident region on which the first light is incident, a light shielding portion is provided between outside of the light incident region and an end portion of the first light modulating element.

4. The projector according to claim 1 or 2, wherein the reflection portion is provided to a partition portion of a substrate on the first surface side of the first light modulating element.

5. The projector according to claim 1 or 2, wherein the reflection portion is provided to a fixing member of the first light modulating element.

6. The projector according to claim 1 or 2, wherein the reflection portion is provided to a metal layer of a substrate which overlaps a wiring layer formed around an opening portion of the display region in plan view.

7. The projector according to claim 1 or 2, wherein a focal length of the first parallelizing element is longer than a length from the first incident end to the first emission end, a focal length of the second parallelizing element is longer than a length from the second incident end to the second emission end, a focal length of the third parallelizing element is longer than a length from the third incident end to the third emission end.

8. The projector according to claim 1 or 2, wherein the first light source has: a light emitter; and a fluorescent body which emits the first light as fluorescent light using excitation light emitted from the light emitter.

9. The projector according to claim 1 or 2, wherein a cross-sectional shape of the first light guide element is rectangular, a cross-sectional shape of the second light guide element is rectangular, a cross-sectional shape of the third light guide element is rectangular.

10. The projector according to claim 1 or 2, wherein the projector has: ​ a first polarizing element disposed between the first parallelizing element and the first light modulating element, which transmits a portion of the first light having a first polarizing component and reflects another portion; a second polarizing element disposed between the second parallelizing element and the second light modulating element, which transmits a portion of the second light having a second polarizing component and reflects another portion; a third polarizing element disposed between the third parallelizing element and the third light modulating element, which transmits a portion of the third light having a third polarizing component and reflects another portion, another portion of the first light is incident on the first light guide element, another portion of the second light is incident on the second light guide element, another portion of the third light is incident on the third light guide element.

11. The projector according to claim 1 or 2, wherein a cross-sectional area of the first exit end is larger than a cross-sectional area of the first entrance end, a cross-sectional area of the second exit end is larger than a cross-sectional area of the second entrance end, a cross-sectional area of the third exit end is larger than a cross-sectional area of the third entrance end.

12. The projector according to claim 1 or 2, wherein the first light guide element, the second light guide element, and the third light guide element are made of glass or metal.

13. The projector according to claim 1 or 2, wherein the first light guide element, the second light guide element, and the third light guide element are hollow, a reflecting film is provided on an inner side surface of the first light guide element, the second light guide element, and the third light guide element.

14. The projector according to claim 1 or 2, wherein a cross-sectional shape of the first light guide element is rectangular, a cross-sectional shape of the second light guide element is rectangular, a cross-sectional shape of the third light guide element is rectangular, when a gradient angle of a side surface of the first light guide element, the second light guide element, and the third light guide element including a short side is α, 7° ≤ α ≤ 22°, when a gradient angle of a side surface of the first light guide element, the second light guide element, and the third light guide element including a long side is β, 14° ≤ β ≤ 36°, a reflecting film is provided on an inner side surface of the first light guide element, the second light guide element, and the third light guide element.

15. The projector according to claim 1 or 2, wherein When the reflectance of the reflection film is the highest, the incident angle of light incident to the reflection film is θ in , and 60°≤θ in ≤90°. the projector has: a fourth polarizing element disposed between the first light modulating element and the light combining element, which transmits a portion of light emitted from the first light modulating element having a fourth polarizing component and absorbs another portion; a fifth polarizing element disposed between the second light modulating element and the light combining element, which transmits a portion of light emitted from the second light modulating element having a fifth polarizing component and absorbs another portion; and a sixth polarizing element disposed between the third light modulating element and the light combining element, which transmits a portion of light emitted from the third light modulating element having a sixth polarizing component and absorbs another portion. ​

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