Light source device and projector

Abstract

To provide a light source device and a projector capable of efficiently extracting illumination light.SOLUTION: A light source device includes: a substrate having a supporting surface; a light source emitting first light in a first wavelength range; a first optical member having a first optical layer facing the supporting surface and reflecting the first light emitted from the light source; a first wavelength conversion layer disposed on the supporting surface and converting the first light into second light in a second wavelength range; a second wavelength conversion layer disposed at a first wavelength conversion layer side with respect to the first optical layer, and converting the first light into third light in a third wavelength range; and a light emitting portion formed by at least the substrate and the first optical member and emitting light. The first optical layer is inclined with respect to a light incident surface and further reflects the second light and the third light, the second wavelength conversion layer converts a part of the first light emitted from the light source into the third light, the first wavelength conversion layer converts a part of the first light emitted from the second wavelength conversion layer into the second light, and the light emitting portion emits the first light, the second light, and the third light.SELECTED DRAWING: Figure 5

Description

[Technical Field]

[0001] The present invention relates to a light source device and a projector. [Background technology]

[0002] Conventionally, there is a light source device that reflects linearly polarized excitation light emitted from a light source toward a phosphor by a polarizing beam splitter, and generates white light using fluorescence emitted from the phosphor and a portion of the excitation light (see, for example, Patent Document 1 below). [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Laid-Open No. 2012-004009 Summary of the Invention [Problem to be solved by the invention]

[0004] However, the above light source device had a problem in that the excitation light, whose polarization direction is disturbed when emitted from the phosphor, returns to the light source and cannot be used as illumination light, making it impossible to efficiently extract illumination light. [Means for solving the problem]

[0005] In order to solve the above problems, according to one aspect of the present invention, there is provided a first optical member including a substrate having a support surface, a light source disposed on the support surface side and emitting first light in a first wavelength band, a first optical member having a first optical layer facing the support surface and reflecting the first light emitted from the light source, a first wavelength conversion layer disposed on the support surface and having a light incident surface onto which the first light is incident and converting the first light into second light in a second wavelength band different from the first wavelength band, and a second optical member disposed on the first wavelength conversion layer side of the first optical layer and converting the first light into second light in a second wavelength band different from the first wavelength band. and a light emitting section formed by at least a substrate and a first optical member and emitting light, wherein the first optical layer is inclined with respect to the light incident surface and further reflects the second light and the third light, the second wavelength conversion layer converts a portion of the first light emitted from the light source into the third light, the first wavelength conversion layer converts a portion of the first light emitted from the second wavelength conversion layer into the second light, and the light emitting section emits the first light, the second light, and the third light.

[0006] According to a second aspect of the present invention, there is provided a projector comprising a light source device according to the first aspect of the present invention, a light modulation device that modulates light from the light source device in accordance with image information, and a projection optical device that projects the light modulated by the light modulation device. [Brief explanation of the drawings]

[0007] [Figure 1] FIG. 1 is a diagram showing a schematic configuration of a projector according to a first embodiment. [Figure 2] FIG. 2 is a schematic diagram illustrating the configuration of a lighting device. [Figure 3] FIG. 2 is a perspective view showing a configuration of a main part of a light source device. [Figure 4] FIG. [Figure 5] FIG. 2 is a cross-sectional view of the light source device. [Figure 6] FIG. 10 is a diagram illustrating a configuration of a light source device according to a second embodiment. [Figure 7] FIG. 10 is a diagram illustrating a configuration of a light source device according to a third embodiment. [Figure 8] FIG. 10 is a plan view of a first phosphor layer according to a first modified example. [Figure 9] FIG. 10 is a cross-sectional view showing a schematic configuration of a light source device according to a second modified example. DETAILED DESCRIPTION OF THE INVENTION

[0008] Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. In addition, the drawings used in the following explanation may show characteristic parts enlarged for convenience in order to make the features easier to understand, and the dimensional ratios of each component may not necessarily be the same as in reality.

[0009] (First embodiment) An example of a projector according to this embodiment will be described. FIG. 1 is a diagram showing a schematic configuration of a projector according to this embodiment. 1, the projector 1 of this embodiment is a projection-type image display device that displays a color image on a screen SCR. The projector 1 includes a color separation optical system 3, a light modulation device 4R, a light modulation device 4G, and a light modulation device 4B, a combining optical system 5, a projection optical device 6, and an illumination device 2.

[0010] The color separation optical system 3 separates the white illumination light WL from the illumination device 2 into red light LR, green light LG, and blue light LB. The color separation optical system 3 includes a first dichroic mirror 7a, a second dichroic mirror 7b, a first reflecting mirror 8a, a second reflecting mirror 8b, and a third reflecting mirror 8c, and a first relay lens 9a and a second relay lens 9b.

[0011] The first dichroic mirror 7a separates the illumination light WL from the illumination device 2 into red light LR and other light, green light LG and blue light LB. The first dichroic mirror 7a transmits the separated red light LR and reflects the other light. The second dichroic mirror 7b reflects the green light LG and transmits the blue light LB.

[0012] The first reflecting mirror 8a reflects the red light LR toward the optical modulation device 4R. The second reflecting mirror 8b and the third reflecting mirror 8c guide the blue light LB to the optical modulation device 4B. The green light LG is reflected from the second dichroic mirror 7b toward the optical modulation device 4G.

[0013] The first relay lens 9a is disposed after the second dichroic mirror 7b in the optical path of the blue light LB, and the second relay lens 9b is disposed after the second reflecting mirror 8b in the optical path of the blue light LB.

[0014] The light modulation device 4R modulates the red light LR according to image information to form image light corresponding to the red light LR. The light modulation device 4G modulates the green light LG according to image information to form image light corresponding to the green light LG. The light modulation device 4B modulates the blue light LB according to image information to form image light corresponding to the blue light LB.

[0015] For example, a transmissive liquid crystal panel is used for the light modulation device 4R, the light modulation device 4G, and the light modulation device 4B. Furthermore, polarizing plates (not shown) are arranged on the entrance side and exit side of the liquid crystal panel, respectively, and are configured to pass only linearly polarized light in a specific direction.

[0016] Field lenses 10R, 10G, and 10B are arranged on the incident sides of optical modulation device 4R, optical modulation device 4G, and optical modulation device 4B, respectively. Field lenses 10R, 10G, and 10B collimate the chief rays of red light LR, green light LG, and blue light LB incident on optical modulation device 4R, optical modulation device 4G, and optical modulation device 4B, respectively.

[0017] The combining optical system 5 receives the image light emitted from the light modulation device 4R, the light modulation device 4G, and the light modulation device 4B, combines the image light corresponding to the red light LR, the green light LG, and the blue light LB, and emits the combined image light toward the projection optical device 6. The combining optical system 5 may be, for example, a cross dichroic prism.

[0018] The projection optical device 6 is made up of a plurality of lenses. The projection optical device 6 enlarges and projects the image light combined by the combining optical system 5 onto the screen SCR, thereby displaying an image on the screen SCR.

[0019] (Lighting equipment) FIG. 2 is a schematic diagram of the lighting device 2. As shown in FIG. As shown in FIG. 2, the illumination device 2 includes a light source device 25, a pickup optical system 26, an integrator optical system 35, a polarization conversion element 36, and a superimposing lens 37.

[0020] The light source device 25 emits white illumination light WL toward the pickup optical system .

[0021] The configuration of light source device 25 will be described in detail below. In the following drawings, each component of light source device 25 will be described using an XYZ coordinate system as necessary. The X axis is an axis parallel to the optical axis ax of light source device 25, the Z axis is an axis perpendicular to the optical axis ax and parallel to the normal to substrate 252 that constitutes light source device 25, and the Y axis is an axis perpendicular to both the X axis and the Z axis. Note that the optical axis ax of light source device 25 coincides with the illumination optical axis ax1 of illumination device 2 shown in FIG. 2.

[0022] Fig. 3 is a perspective view showing the configuration of the main part of the light source device 25. Fig. 4 is a front view of the light source device 25 as viewed from the +X side. Fig. 5 is a cross-sectional view of the light source device 25 along the XZ plane.

[0023] As shown in Figures 3 to 5, the light source device 25 of this embodiment includes a light source 250, a first phosphor layer (first wavelength conversion layer) 251, a substrate 252, a mirror layer 253, a first optical member 254, a second optical member 255, a third optical member 256, a second phosphor layer (second wavelength conversion layer) 258, a translucent member 259, and a light emitting section 260.

[0024] The light source 250 has a light emitting element 250a, a base material 250b, and a reflective layer 250c. The light emitting element 250a is configured as a light emitting diode (LED) and emits excitation light (first light) EL. The excitation light EL is light having a blue wavelength band (first wavelength band) of 400 nm to 480 nm, for example, a light beam with a peak wavelength of 455 nm. The base material 250b supports the light emitting element 250a and also functions as a heat dissipation substrate that dissipates heat from the light emitting element 250a. The reflective layer 250c is provided between the base material 250b and the light emitting element 250a. The reflective layer 250c is provided on a surface 250b1 of the base material 250b. The reflective layer 250c is configured as, for example, a metal layer or a dielectric layer.

[0025] The substrate 252 has a support surface 2521 that supports the first phosphor layer 251. The substrate 252 is a metal plate that has excellent heat dissipation properties, such as aluminum or copper. The support surface 2521 is a surface parallel to the XY plane. A recess 261 is formed in the support surface 2521 of the substrate 252. The light source 250 is provided on the support surface 2521 side of the substrate 252. In this embodiment, the light source 250 is disposed in the recess 261 formed in the support surface 2521. A base material 250b of the light source 250 and a surface 261a of the recess 261 are thermally connected. Because the light source 250 is thermally connected to the substrate 252, the light emitting element 250a can be cooled by dissipating heat from the light source 250 to the substrate 252.

[0026] The first phosphor layer 251 is a plate-shaped phosphor including a front surface (light incident surface) 2511, a side surface 2512, and a back surface 2513. The front surface 2511 is the surface onto which excitation light EL is incident. The side surface 2512 is a surface that intersects with the front surface 2511. The side surface 2512 may be perpendicular to the front surface 2511. The back surface 2513 is the surface opposite to the front surface 2511. In this embodiment, excitation light emitted from the second phosphor layer 258 is incident on the surface 2511 of the first phosphor layer 251, as will be described later.

[0027] The first phosphor layer 251 includes phosphor particles that are excited by excitation light and emit fluorescent light (second light) YL, which is yellow light having a yellow wavelength band (second wavelength band) of, for example, 550 to 640 nm. Examples of the phosphor particles include YAG (yttrium aluminum garnet) phosphors. The phosphor particles may be made of a single material, or a mixture of particles formed using two or more materials may be used. The first phosphor layer 251 may be, for example, a phosphor layer in which phosphor particles are dispersed in an inorganic binder such as alumina, or a phosphor layer in which phosphor particles are sintered without using a binder. The first phosphor layer 251 includes a plurality of scatterers K1. The scatterers K1 may be pores or transparent particles with a refractive index different from that of the phosphors. In this embodiment, pores are used as the scatterers K1.

[0028] The substrate 252 is thermally connected to the first phosphor layer 251. Because the substrate 252 is thermally connected to the first phosphor layer 251, the substrate 252 cools the first phosphor layer 251 by dissipating heat from the first phosphor layer 251.

[0029] The first phosphor layer 251 has a cutout portion 251K formed by cutting out a portion of the first phosphor layer 251. The cutout portion 251K penetrates the first phosphor layer 251, so that a portion of the substrate 252 is exposed.

[0030] The first phosphor layer 251 is supported on the support surface 2521 of the substrate 252 so that the recess 261 faces the cutout portion 251K in a plan view. As described above, the light source 250 is disposed in the recess 261. Therefore, the light source 250 is disposed in the cutout portion 251K. The cutout portion 251K has a rectangular planar shape. The size of the cutout portion 251K is equal to or slightly larger than the outer shape of the light source 250.

[0031] The mirror layer 253 is provided between the substrate 252 and the first phosphor layer 251. The area of ​​the mirror layer 253 is larger than the area of ​​the back surface 2513 of the first phosphor layer 251. The mirror layer 253 is provided at least around the periphery of the first phosphor layer 251 on the support surface 2521 of the substrate 252. The first phosphor layer 251 is bonded to the support surface 2521 of the substrate 252 via the mirror layer 253. The mirror layer 253 is made of, for example, a metal layer or a dielectric layer. The mirror layer 253 may be formed over the entire support surface 2521. Alternatively, a portion of the mirror layer 253 may be formed directly on the back surface 2513 of the first phosphor layer 251.

[0032] The first optical member 254 is disposed so as to face the support surface 2521 of the substrate 252. In other words, the first optical member 254 is disposed so as to face the surface 2511 of the first phosphor layer 251. The first optical member 254 is disposed so as not to come into contact with the first phosphor layer 251.

[0033] The first optical member 254 is disposed in a state inclined with respect to the surface 2511 of the first phosphor layer 251. The angle that the first optical member 254 forms with respect to the surface 2511 of the first phosphor layer 251 is set to an acute angle.

[0034] The first optical member 254 includes a base material 2541 and a first optical layer 2542. The base material 2541 may be made of a light-transmitting material such as alumina, sapphire, or glass, or a non-light-transmitting material such as metal. The first optical layer 2542 is made of, for example, a dielectric multilayer film or a metal film. The first optical member 254 functions as a mirror that reflects incident light. The first optical layer 2542 reflects fluorescence YL and YL1 (second light and third light) (described later) in addition to the excitation light EL from the light source 250.

[0035] The second phosphor layer 258 is disposed on the first phosphor layer 251 side of the first optical member 254, that is, on the first phosphor layer 251 side of the first optical layer 2542. In the present embodiment, the second phosphor layer 258 is provided on the first optical layer 2542.

[0036] The second phosphor layer 258 is a plate-shaped phosphor including a front surface (light incident surface) 2581, a side surface 2582, and a back surface 2583. The front surface 2581 is the surface onto which excitation light EL is incident. The back surface 2583 abuts the first optical layer 2542 and is the surface opposite to the front surface 2581. The side surface 2582 is a surface that intersects with the front surface 2581. The side surface 2582 may be perpendicular to the front surface 2581.

[0037] In this embodiment, the second phosphor layer 258 is made of the same phosphor material as the first phosphor layer 251. The second phosphor layer 258 converts the excitation light EL into fluorescence YL1, which is yellow light having a yellow wavelength band of, for example, 550 to 640 nm, different from the blue wavelength band (first wavelength band). In other words, the second phosphor layer 258 converts a portion of the excitation light EL emitted from the light source 250 into fluorescence YL1. In this embodiment, the yellow wavelength band (third wavelength band) of the fluorescence YL1 emitted by the second phosphor layer 258 is the same as the yellow wavelength band (second wavelength band) of the fluorescence YL emitted by the first phosphor layer 251.

[0038] The second phosphor layer 258 includes a plurality of scatterers K2. The scatterers K2 are made of pores or transparent particles having a refractive index different from that of the phosphor. In this embodiment, pores are used as the scatterers K2.

[0039] In this embodiment, the degree of light scattering in the second phosphor layer 258 is smaller than the degree of light scattering in the first phosphor layer 251. The degree of light scattering can be adjusted by the number of scatterers contained in the phosphor. In this embodiment, the number of scatterers K2 contained in the second phosphor layer 258 is smaller than the number of scatterers K1 contained in the first phosphor layer 251. For example, by using a single crystal phosphor, it is possible to achieve a second phosphor layer 258 with a small number of scatterers. The second phosphor layer 258 has less backscattering of light than the first phosphor layer 251, and therefore the excitation light EL incident from the light source 250 can easily be transmitted without being scattered within the phosphor.

[0040] Furthermore, in this embodiment, the thickness H2 of the second phosphor layer 258 is smaller than the thickness H1 of the first phosphor layer 251. The thickness H2 of the second phosphor layer 258 is a dimension along the normal direction to the surface on which the second phosphor layer 258 is provided (the surface of the first optical layer 2542 of the first optical member 254), and the thickness H1 of the first phosphor layer 251 is a dimension along the normal direction to the support surface 2521 on which the first phosphor layer 251 is provided. In other words, the thickness H2 of the second phosphor layer 258 is a dimension along the normal direction to the surface 2581 (light incident surface) of the second phosphor layer 258, and the thickness H1 of the first phosphor layer 251 is a dimension along the normal direction to the surface 2511 (light incident surface) of the first phosphor layer 251.

[0041] As the thickness of the phosphor decreases, the excitation light is more likely to exit the phosphor before being converted into fluorescent light. In this embodiment, as described above, the fluorescence conversion efficiency of the second phosphor layer 258 is suppressed by suppressing the backscattering and thickness of the second phosphor layer 258 relative to the first phosphor layer 251. As a result, most of the excitation light EL emitted from the light source 250 is not converted into fluorescence in the second phosphor layer 258, but passes through the second phosphor layer 258 and enters the first optical member 254, and is reflected by the first optical layer 2542 of the first optical member 254. At least a portion of the excitation light EL reflected by the first optical layer 2542 passes through the second phosphor layer 258 and is emitted from the second phosphor layer 258 toward the first phosphor layer 251.

[0042] In the second phosphor layer 258, a portion of the fluorescence YL1 is emitted directly from the surface 2581 of the second phosphor layer 258, and the remaining portion of the fluorescence YL1 travels toward the first optical member 254, is reflected by the first optical layer 2542, and is emitted from the surface 2581.

[0043] The second phosphor layer 258 emits the fluorescence YL1 obtained by wavelength-converting the excitation light EL, as well as most of the excitation light EL that has not been wavelength-converted. That is, the second phosphor layer 258 emits light that includes the fluorescence YL1 and the excitation light EL.

[0044] In this embodiment, the first phosphor layer 251 converts a portion of the excitation light EL emitted from the second phosphor layer 258 into fluorescence YL. That is, the first phosphor layer 251 is excited by the excitation light EL that is indirectly incident via the second phosphor layer 258, rather than by the excitation light EL that is emitted from the light source 250 and directly incident thereon.

[0045] 4 and 5, the light-transmitting member 259 is provided in contact with the light emission side (+X side) of the light source 250. In the present embodiment, the light-transmitting member 259 is in contact with the light-emitting element 250a of the light source 250. The light-transmitting member 259 has the same size as the notch portion 251K formed in the first phosphor layer 251, and is fitted into the notch portion 251K. The light-transmitting member 259 also functions as a heat dissipation member for the light-emitting element 250a of the light source 250.

[0046] In this embodiment, surface 259a of light-transmitting member 259 on the first optical member 254 side is flush with surface 2511 of first phosphor layer 251. In other words, surface 259a of light-transmitting member 259 and surface 2511 of first phosphor layer 251 are arranged on the same plane in the direction along the normal to support surface 2521 of substrate 252.

[0047] The light-transmitting member 259 includes a light-transmitting substrate 2591 and a second optical layer 2592. The light-transmitting substrate 2591 is made of a light-transmitting material such as alumina, sapphire, or glass. The second optical layer 2592 is provided on the outer surface of the light-transmitting substrate 2591, i.e., on the side opposite the light source 250. The second optical layer 2592 has the property of transmitting the excitation light EL and reflecting the fluorescence. As a result, the light-transmitting member 259 transmits the excitation light EL emitted from the light source 250 while reflecting the fluorescence YL generated in the first phosphor layer 251 and the fluorescence YL1 generated in the second phosphor layer 258. An anti-reflection film such as an AR coating is provided on the inner surface of the light-transmitting substrate 2591, i.e., on the light source 250 side. As a result, the light-transmitting member 259 suppresses reflection of the excitation light EL emitted from the light source 250, allowing the excitation light EL to efficiently enter the interior.

[0048] The light emitting portion 260 is an opening formed in each end surface on the +X side of the substrate 252, the first optical member 254, the second optical member 255, and the third optical member 256. The light emitting portion 260 emits white illumination light WL containing excitation light EL, fluorescence YL, and fluorescence YL1.

[0049] The second optical member 255 includes a base material 2551 and a third optical layer 2552. The base material 2551 may be made of a light-transmitting material such as alumina, sapphire, or glass, or a non-light-transmitting material such as metal. The third optical layer 2552 is formed on the inner surface of the base material 2551. The third optical layer 2552 is made of, for example, a dielectric multilayer film or a metal film.

[0050] The second optical member 255 is disposed so as to intersect the support surface 2521 of the substrate 252 and the first optical member 254. The second optical member 255 is disposed so that the third optical layer 2552 intersects the support surface 2521 and the first optical layer 2542. The second optical member 255 may be perpendicular to the support surface 2521 of the substrate 252 and the first optical member 254. The third optical layer 2552 may be perpendicular to the support surface 2521 and the first optical layer 2542. The second optical member 255 is disposed so that its thickness direction coincides with the Y-axis direction. The second optical member 255 is disposed near the +Y side of the first phosphor layer 251 and the second phosphor layer 258. Therefore, a portion of the fluorescence YL, YL1 emitted from the first phosphor layer 251 or the second phosphor layer 258 toward the +Y side is reflected by the third optical layer 2552 of the second optical member 255. The second optical member 255 reflects not only the fluorescence YL, YL1 but also the excitation light EL.

[0051] The second optical member 255 is in the shape of a trapezoidal plate. As shown in FIG. 3 , the second optical member 255 includes a first end face 55a forming the upper base of the trapezoid, a second end face 55b forming the lower base of the trapezoid, a third end face 55c connecting the first end face 55a and the second end face 55b on the +X side, and a fourth end face 55d connecting the first end face 55a and the second end face 55b on the -X side. The first end face 55a, the second end face 55b, the third end face 55c, and the fourth end face 55d are all flat surfaces. The third end face 55c faces the substrate 252. The fourth end face 55d is the surface of the base material 2551 opposite the third end face 55c. The first optical member 254 abuts against the fourth end face 55d. The first optical member 254 is placed on the fourth end face 55d. The first optical layer 2542 is in contact with the fourth end face 55d. The base material 2541 is placed on the fourth end face 55d with the first optical layer 2542 interposed therebetween.

[0052] Here, when glass is used as the material for base material 2551, chamfering is required to prevent chipping by removing sharp edges. In this embodiment, second optical member 255 is formed in a trapezoidal plate shape, which eliminates the need for chamfering, thereby improving the workability of base material 2551.

[0053] In this embodiment, a portion of the second optical member 255 is embedded in the substrate 252. Therefore, the second optical member 255 is firmly supported by the substrate 252. A part of the end portion on the +X side of second optical member 255 is fitted into groove 2524 formed in support surface 2521 of substrate 252. The gap between second optical member 255 and groove 2524 may be filled with adhesive.

[0054] Specifically, the second optical member 255 has the entire first end face 55a and the entire third end face 55c and a portion of the second end face 55b fitted into the groove 2524. An edge 55d1 of the fourth end face 55d that is located closest to the -X side and extends along the Z direction is flush with the support surface 2521 of the substrate 252. This allows a smooth connection between the fourth end face 55d and the support surface 2521 of the substrate 252. Furthermore, on the +X side, the second end face 55b is flush with the end face 52 of the substrate 252.

[0055] The third optical member 256 has a configuration similar to that of the second optical member 255 . That is, the third optical member 256 includes a base material 2561 and a fourth optical layer 2562. The fourth optical layer 2562 is formed on the inner surface of the base material 2561.

[0056] The third optical member 256 is disposed so as to intersect the support surface 2521 of the substrate 252 and the first optical member 254 and face the second optical member 255. The third optical member 256 is disposed so that the fourth optical layer 2562 intersects the support surface 2521 and the first optical layer 2542 and faces the third optical layer 2552. The third optical member 256 may be perpendicular to the support surface 2521 of the substrate 252 and the first optical member 254. The fourth optical layer 2562 may be perpendicular to the support surface 2521 and the first optical layer 2542. The third optical member 256 is disposed so that its thickness direction coincides with the Y-axis direction. The third optical member 256 is disposed near the -Y sides of the first phosphor layer 251 and the second phosphor layer 258. Therefore, the fluorescence YL, YL1 emitted from the first phosphor layer 251 or the second phosphor layer 258 toward the -Y side and incident on the third optical member 256 is reflected by the fourth optical layer 2562 of the third optical member 256. The third optical member 256 reflects not only the fluorescence YL, YL1 but also the excitation light EL.

[0057] The third optical member 256 is a trapezoidal plate similar to the second optical member 255 . The third optical member 256 includes a first end face 56a forming the upper base of the trapezoid, a second end face 56b forming the lower base of the trapezoid, a third end face 56c connecting the first end face 56a and the second end face 56b on the +X side, and a fourth end face 56d connecting the first end face 56a and the second end face 56b on the -X side. The first end face 56a, the second end face 56b, the third end face 56c, and the fourth end face 56d are all flat surfaces. The third end face 56c faces the substrate 252. The fourth end face 56d is the surface of the base material 2561 opposite the third end face 56c. The first optical member 254 abuts against the fourth end face 56d. The first optical member 254 is placed on the fourth end face 56d. The first optical layer 2542 is in contact with the fourth end face 56d. The base material 2541 is placed on the fourth end face 56d with the first optical layer 2542 interposed therebetween.

[0058] In this embodiment, a portion of the third optical member 256 is embedded in the substrate 252, so that the third optical member 256 is firmly supported by the substrate 252. A part of the end portion on the +X side of the third optical member 256 is fitted into a groove 2524 formed in the support surface 2521 of the substrate 252. The gap between the third optical member 256 and the groove 2524 may be filled with an adhesive.

[0059] Specifically, the third optical member 256 has the entire first end face 56a and the entire third end face 56c and a portion of the second end face 56b fitted into the groove 2524. An edge 56d1 of the fourth end face 56d that is located closest to the -X side and extends along the Z direction is flush with the support surface 2521 of the substrate 252. This allows a smooth connection between the fourth end face 56d and the support surface 2521 of the substrate 252. Furthermore, on the +X side, the second end face 56b is flush with the end face 52 of the substrate 252.

[0060] In this embodiment, the first optical member 254 is supported by the second optical member 255 and the third optical member 256. The first optical member 254 is fixed to the second optical member 255 and the third optical member 256 by adhesive. Specifically, the first optical member 254 is disposed so as to bridge between the fourth end surface 55d of the second optical member 255 and the fourth end surface 56d of the third optical member 256. On the -X side, the inner end side 54a of the first optical member 254 contacts the support surface 2521 of the substrate 252.

[0061] Based on this configuration, light source device 25 of this embodiment closes the -X side with substrate 252, first optical member 254, second optical member 255, and third optical member 256, and forms light emission section 260 on the +X side. Therefore, light source device 25 prevents light leakage from the fluorescence YL on the side opposite to light emission section 260, and can efficiently emit light from light emission section 260.

[0062] The light source 250 emits excitation light EL in Lambertian emission. The excitation light EL emitted from the light source 250 passes through the light-transmitting member 259 and enters the entire area of ​​the second phosphor layer 258 disposed opposite the light source 250.

[0063] In this embodiment, the second phosphor layer 258 has reduced backscattering and thickness compared to the first phosphor layer 251, thereby reducing the fluorescence conversion efficiency. For this reason, most of the excitation light EL passes through the second phosphor layer 258 without being converted into fluorescence and enters the first optical layer 2542 of the first optical member 254. The first optical layer 2542 reflects the excitation light EL toward the support surface 2521 of the substrate 252. At least a portion of the excitation light EL reflected by the first optical layer 2542 passes through the second phosphor layer 258 and is emitted toward the support surface 2521 of the substrate 252. Note that a portion of the excitation light EL is backscattered by the second phosphor layer 258 or reflected by the surface thereof and is emitted toward the support surface 2521 of the substrate 252.

[0064] In this way, the second phosphor layer 258 emits a portion of the excitation light EL toward the support surface 2521 of the substrate 252. Hereinafter, of the excitation light EL emitted from the light source 250, the light emitted from the second phosphor layer 258 toward the support surface 2521 of the substrate 252 will be referred to as excitation light EL1.

[0065] A portion of the excitation light EL incident on the second phosphor layer 258 is converted into fluorescence YL1. The fluorescence YL1 is emitted from the second phosphor layer 258 via the first optical layer 2542 or without passing through the first optical layer 2542. At least a portion of the fluorescence YL1 emitted from the second phosphor layer 258 is emitted from the light emitting portion 260. Furthermore, part of the fluorescence YL1 is incident on the support surface 2521 of the substrate 252 and is reflected by the mirror layer 253 formed on the support surface 2521. At least part of the fluorescence YL reflected by the mirror layer 253 is emitted from the light emitting portion 260. Furthermore, a portion of the fluorescence YL1 enters the first phosphor layer 251, is backscattered in the first phosphor layer 251, and is emitted from the light emitting portion 260. Furthermore, a part of the fluorescence YL 1 incident on the first phosphor layer 251 is transmitted through the first phosphor layer 251 and is reflected by the mirror layer 253 , and is then emitted from the light emitting portion 260 .

[0066] The excitation light EL1 emitted from the second phosphor layer 258 is incident on the first phosphor layer 251. As described above, the first phosphor layer 251 has a higher degree of light scattering and a larger thickness than the second phosphor layer 258, thereby increasing the fluorescence conversion efficiency. Therefore, most of the excitation light EL1 emitted from the second phosphor layer 258 is converted into fluorescence YL in the first phosphor layer 251. At least a portion of the fluorescence YL emitted from the first phosphor layer 251 is emitted from the light emitting section 260.

[0067] Furthermore, a part of the fluorescence YL emitted from the first phosphor layer 251 enters the second phosphor layer 258 , is backscattered or reflected by the second phosphor layer 258 , and is emitted from the light emitting portion 260 . Furthermore, a portion of the fluorescence YL incident on the second phosphor layer 258 passes through the second phosphor layer 258 and is reflected by the first optical layer 2542 of the first optical member 254 , and is then emitted from the light emitting portion 260 . In addition, a portion of the fluorescence YL reflected by the first optical layer 2542 of the first optical member 254 is incident on the support surface 2521 of the substrate 252, reflected by the mirror layer 253 formed on the support surface 2521, and emitted from the light emitting section 260.

[0068] Furthermore, a portion of the fluorescence YL, YL1 enters the light-transmitting member 259 and is reflected by a second optical layer 2592 provided on the outer surface of the light-transmitting member 259. At least a portion of the fluorescence YL, YL1 reflected by the second optical layer 2592 of the light-transmitting member 259 is emitted from the light emitting portion 260.

[0069] Furthermore, when a portion of the excitation light EL1 emitted from the second phosphor layer 258 enters the light-transmitting member 259, it passes through a second optical layer 2592 provided on the outer surface of the light-transmitting member 259 and enters the light source 250. A portion of the excitation light EL1 that has passed through the second optical layer 2592 is reflected by the reflective layer 250c of the light source 250, passes through the light-transmitting member 259, and is emitted toward the second phosphor layer 258. This light is then used as part of the excitation light or illumination light WL for the second phosphor layer 258 or the first phosphor layer 251.

[0070] Furthermore, a portion of the excitation light EL, EL1 and a portion of the fluorescence YL, YL1 are incident on the second optical member 255 or the third optical member 256 via the mirror layer 253, or are directly incident on the second optical member 255 or the third optical member 256 without passing through the mirror layer 253. A portion of the excitation light EL, EL1 and a portion of the fluorescence YL, YL1 are reflected by the second optical member 255 or the third optical member 256, and are thereby emitted from the light emitting portion 260.

[0071] Note that a portion of the excitation light EL, EL1 and a portion of the fluorescence YL, YL1 propagate in the opposite direction (−X side) from the light emitting portion 260, but are eventually emitted from the light emitting portion 260 by repeated reflection.

[0072] In this way, the light source device 25 of this embodiment can emit white illumination light WL from the light emission section 260, which contains the fluorescence YL generated in the first phosphor layer 251, the fluorescence YL generated in the second phosphor layer 258, and a portion of the excitation light EL, EL1 emitted from the light source 250.

[0073] In the light source device 25 of this embodiment, in the first phosphor layer 251, heat is more likely to accumulate and the temperature is more likely to increase on the -X side, which is the opposite side to the light emission section 260, compared to the side of the light emission section 260 that emits the fluorescence YL. In contrast, in the light source device 25 of this embodiment, as shown in FIGS. 3 and 5 , the substrate 252 that supports the first phosphor layer 251 is shaped so that it is longer on the side opposite to the light emission section 260. Therefore, according to the light source device 25 of this embodiment, it is possible to efficiently cool the side of the first phosphor layer 251 opposite to the light emission section 260, where heat is more likely to accumulate. Therefore, the first phosphor layer 251 can be efficiently cooled.

[0074] Furthermore, in the light source device 25 of this embodiment, the heat of the second phosphor layer 258 is released via the first optical member 254, and therefore the second phosphor layer 258 can be efficiently cooled. Therefore, the fluorescence conversion efficiency of the second phosphor layer 258 can be improved.

[0075] The illumination light WL emitted from the light source device 25 is incident on the pickup optical system 26. The pickup optical system 26 is composed of, for example, pickup lenses 26a and 26b. The pickup optical system 26 has a function of picking up the illumination light WL emitted from the light source device 25 and collimating the light.

[0076] The illumination light WL is incident on the integrator optical system 35. The integrator optical system 35 is made up of, for example, a first lens array 35a and a second lens array 35b. The first lens array 35a includes a plurality of first small lenses 35am, and the second lens array 35b includes a plurality of second small lenses 35bm.

[0077] The first lens array 35a separates the illumination light WL into a plurality of small light beams. The first small lenses 35am focus the small light beams onto the corresponding second small lenses 35bm. The integrator optical system 35 cooperates with a superimposing lens 37 (described later) to homogenize the illuminance distribution in the image formation areas of the light modulation devices 4R, 4G, and 4B shown in FIG. 1, which are the illuminated areas.

[0078] The illumination light WL that has passed through the integrator optical system 35 is incident on the polarization conversion element 36. The polarization conversion element 36 is composed of, for example, a polarization separation film and a retardation plate (half wavelength plate). The polarization conversion element 36 converts the polarization direction of the illumination light WL into one of the polarization components.

[0079] The illumination light WL that has passed through the polarization conversion element 36 is incident on the superimposing lens 37. The illumination light WL that has emerged from the superimposing lens 37 is incident on the color separation optical system 3. The superimposing lens 37 superimposes the plurality of small light beams that make up the illumination light WL on each other in the illuminated areas of the light modulation devices 4R and 4G, i.e., the image formation areas, thereby providing uniform illumination.

[0080] The light source device 25 according to the present embodiment described above provides the following effects. The light source device 25 of this embodiment comprises a substrate 252 having a support surface 2521, a light source 250 arranged on the support surface 2521 side and emitting excitation light EL, a first optical member 254 facing the support surface 2521 and having a first optical layer 2542 that reflects the excitation light EL emitted from the light source 250, a first phosphor layer 251 arranged on the support surface 2521 and having a surface 2511 on which the excitation light EL is incident and converts the excitation light EL into fluorescence YL, a second phosphor layer 258 arranged on the first phosphor layer 251 side of the first optical layer 2542 and converts the excitation light EL into fluorescence YL1, and a light emission section 260 formed at least by the substrate 252 and the first optical member 254 and emitting light. The first optical layer 2542 is inclined with respect to the surface 2511 and further reflects the fluorescence YL and the fluorescence YL1, the second phosphor layer 258 converts the excitation light EL emitted from the light source 250 into the fluorescence YL1, the first phosphor layer 251 converts a portion of the excitation light EL1 emitted from the second phosphor layer 258 into the fluorescence YL, and the light emitting section 260 emits the excitation light EL, the fluorescence YL, and the fluorescence YL1.

[0081] According to the light source device 25 of the present embodiment, the fluorescence YL1 generated by exciting the second phosphor layer 258 with the excitation light EL emitted from the light source 250, the fluorescence YL generated by exciting the first phosphor layer 251 with the excitation light EL1 emitted from the second phosphor layer 258 and not used to excite the fluorescence YL1, and a portion of the excitation light EL emitted from the light source 250 and not used to excite the fluorescence YL, YL1 can be extracted as white illumination light WL from the light emission section 260. Therefore, according to the light source device 25 of the present embodiment, bright white illumination light WL can be emitted from the light emission section 260.

[0082] Furthermore, in light source device 25 of this embodiment, the area of ​​light emitting portion 260 can be regarded as the apparent light-emitting area of ​​the light source device, so the etendue in illumination light WL can be reduced. In light source device 25 of this embodiment, the etendue can be reduced without reducing the incident area of ​​excitation light EL on first phosphor layer 251 or second phosphor layer 258, so that a decrease in fluorescence conversion efficiency due to an increase in the optical density of excitation light EL on first phosphor layer 251 or second phosphor layer 258 can be suppressed. According to the light source device 25 of this embodiment, it is possible to generate bright white illumination light WL with a small etendue while suppressing an increase in the light density of the excitation light EL.

[0083] In the light source device 25 of this embodiment, the fluorescence YL1 emitted from the second phosphor layer 258 is in the same yellow wavelength band as the fluorescence YL emitted from the first phosphor layer 251. The excitation light EL is blue light. The light emitting unit 260 emits white illumination light WL containing the fluorescence YL, YL1, and the excitation light EL.

[0084] According to this configuration, bright white light can be generated as the illumination light WL.

[0085] In the light source device 25 of this embodiment, the thickness H2 of the second phosphor layer 258 is smaller than the thickness H1 of the first phosphor layer 251.

[0086] According to this configuration, compared to when the first phosphor layer 251 and the second phosphor layer 258 have the same thickness, wavelength conversion of the excitation light EL emitted from the light source 250 and incident on the second phosphor layer 258 can be suppressed, and the excitation light EL can be efficiently emitted from the second phosphor layer 258 toward the first phosphor layer 251. This makes it possible to efficiently excite the first phosphor layer 251 and generate the fluorescence YL.

[0087] In the light source device 25 of this embodiment, the degree of scattering of light in the second phosphor layer 258 is smaller than the degree of scattering of light in the first phosphor layer 251.

[0088] According to this configuration, light scattering is suppressed, which makes it easier for the excitation light EL to pass through the second phosphor layer 258. As a result, compared to when the first phosphor layer 251 and the second phosphor layer 258 have the same degree of light scattering, the excitation light EL passes through the second phosphor layer 258 and is more efficiently incident on the first phosphor layer 251. As a result, the first phosphor layer 251 can be efficiently excited to generate the fluorescence YL.

[0089] In the light source device 25 of this embodiment, the first phosphor layer 251 has a cutout portion 251K formed by cutting out a portion thereof, and the light source 250 is disposed in the cutout portion 251K of the first phosphor layer 251.

[0090] According to this configuration, the light source 250 can be arranged at a desired position on the support surface 2521 without interfering with the first phosphor layer 251. This increases the degree of freedom in the layout of the light source 250 on the substrate 252.

[0091] In the light source device 25 of this embodiment, the light source 250 has a light-emitting element 250a that emits excitation light EL, a base material 250b that supports the light-emitting element 250a, and a reflective layer 250c that is provided between the base material 250b and the light-emitting element 250a.

[0092] According to this configuration, the excitation light EL that has returned to the light source 250 can be reflected by the reflective layer 250c and returned to the first optical member 254. This can increase the utilization efficiency of the excitation light EL.

[0093] The light source device 25 of this embodiment further includes a light-transmitting member 259 provided in contact with the light emission side of the light source 250. The light-transmitting member 259 further includes a second optical layer 2592 provided on the opposite side to the light source 250, which transmits the excitation light EL and reflects the fluorescence YL, YL1.

[0094] According to this configuration, heat can be released from the light source 250 by the light-transmitting member 259. As a result, heat from the light source 250 can be released from both the substrate 252 and the light-transmitting member 259, and the heat resistance of the light source 250 can be further improved. Furthermore, the light-transmitting member 259 can reflect a portion of the fluorescence YL, YL1 by the second optical layer 2592 and emit the reflected light from the light emitting portion 260. This can further increase the extraction efficiency of the illumination light WL.

[0095] In the light source device 25 of this embodiment, the substrate 252 has a recess 261 formed in the support surface 2521, the light source 250 is arranged in the recess 261 of the substrate 252, and the surface 259a of the translucent member 259 on the first optical member 254 side is flush with the surface 2511 of the first phosphor layer 251.

[0096] According to this configuration, by disposing the light source 250 in the recess 261, it is possible to dispose the light source 250 and the first optical member 254 at a predetermined distance from each other. This allows the excitation light EL emitted from the light source 250 by Lambertian emission to be efficiently incident on the entire area of ​​the first optical member 254. Furthermore, since no step is generated between the surface 2511 of the light-transmitting member and the surface 2511 of the first phosphor layer 251, the incident surface of light incident from the first optical member 254 side can be made flat. This makes it possible to suppress diffuse reflection of light incident from the first optical member 254 side and to efficiently extract the illumination light WL from the light emitting portion 260.

[0097] The light source device 25 of the present embodiment further includes: a second optical member 255 having a third optical layer 2552 that reflects the excitation light EL and the fluorescence YL, YL1, and arranged so that the third optical layer 2552 intersects the support surface 2521 and the first optical layer 2542; and a third optical member 256 having a fourth optical layer 2562 that reflects the excitation light EL and the fluorescence YL, YL1, and arranged so that the fourth optical layer 2562 intersects the support surface 2521 and the first optical layer 2542 and faces the third optical layer 2552. The light output unit 260 is formed by the substrate 252, the first optical member 254, the second optical member 255, and the third optical member 256.

[0098] According to this configuration, light leakage from other than the light emitting section 260 is suppressed, so that the illumination light WL can be emitted from the light emitting section 260 efficiently.

[0099] The projector 1 according to the present embodiment described above provides the following advantages. The projector 1 of this embodiment includes a light source device 25, light modulation devices 4B, 4G, and 4R that form image light by modulating blue light LB, green light LG, and red light LR from the light source device 25 according to image information, and a projection optical device 6 that projects the image light. According to the projector 1 of this embodiment, since it is provided with the light source device 25 that generates bright illumination light WL, it is possible to form and project a high-brightness image.

[0100] (Second embodiment) Next, a configuration of a light source device according to a second embodiment of the present invention will be described. In this embodiment, the same components or members as those in the first embodiment are denoted by the same reference numerals, and detailed descriptions thereof will be omitted.

[0101] FIG. 6 is a diagram showing the configuration of the light source device of this embodiment. As shown in FIG. 6, the light source device 125 of this embodiment includes a light source 250, a first phosphor layer 251, a substrate 252, a mirror layer 253, a first optical member 254, a second optical member 255, a third optical member 256, a second phosphor layer (second wavelength conversion layer) 1258, a translucent member 259, and a light emitting section 260.

[0102] In this embodiment, the second phosphor layer 1258 is made of a different phosphor material from that of the first phosphor layer 251. The second phosphor layer 1258 converts the excitation light EL into fluorescence (third light) RL, which is red light having a red wavelength band of, for example, 600 to 800 nm, different from the blue wavelength band. In this embodiment, the red wavelength band (third wavelength band) of the fluorescence RL emitted by the second phosphor layer 1258 is wider than the yellow wavelength band (second wavelength band) of the fluorescence YL emitted by the first phosphor layer 251 and the blue wavelength band (first wavelength band) of the excitation light EL emitted by the light source 250.

[0103] As such a red phosphor, for example, any of Pr, Eu, and Cr is dispersed as an activator (Y 1-x ,Gd x )3(Al,Ga)5O 12 A YAG-based phosphor (either Pr:YAG, Eu:YAG, or Cr:YAG) consisting of the above is used. The activator may contain one element selected from Pr, Eu, and Cr, or may be a co-activator containing multiple elements selected from Pr, Eu, and Cr.

[0104] In this embodiment, the degree of light scattering in second phosphor layer 1258 is smaller than the degree of light scattering in first phosphor layer 251. In this embodiment, the number of scatterers contained in second phosphor layer 1258 is smaller than the number of scatterers contained in first phosphor layer 251.

[0105] Also in this embodiment, by making the thickness of the second phosphor layer 1258 smaller than the thickness of the first phosphor layer 251, the fluorescence conversion efficiency in the second phosphor layer 1258 is suppressed, making it easier to transmit the excitation light EL.

[0106] According to the light source device 125 of this embodiment described above, the fluorescence RL generated by exciting the second phosphor layer 1258 with the excitation light EL emitted from the light source 250, the fluorescence YL generated by exciting the first phosphor layer 251 with the excitation light EL emitted from the second phosphor layer 1258 and not used to excite the fluorescence RL, and a portion of the excitation light EL emitted from the light source 250 and not used to excite the fluorescence RL and YL can be extracted as illumination light WL1 from the light emission section 260. Therefore, according to the light source device 125 of this embodiment, bright illumination light WL1 can be emitted from the light emission section 260.

[0107] Here, for example, when generating white illumination light of 6500K, the red component is insufficient using only yellow fluorescence. In contrast, in the light source device 125 of this embodiment, the red component of the illumination light WL1 can be supplemented by the fluorescence RL, which is red light generated by the second phosphor layer 1258. Therefore, the light source device 125 of this embodiment can generate white illumination light WL1 with high color reproducibility and containing a sufficient amount of red component. Therefore, a projector equipped with the light source device 125 of this embodiment can project an image with high brightness and high reproducibility of red.

[0108] (Third embodiment) Next, the configuration of a light source device according to a third embodiment of the present invention will be described. In this embodiment, the same components or members as those in the second embodiment are denoted by the same reference numerals, and detailed descriptions thereof will be omitted.

[0109] FIG. 7 is a diagram showing the configuration of the light source device of this embodiment. As shown in FIG. 7, the light source device 225 of this embodiment includes a light source 250, a first phosphor layer (first wavelength conversion layer) 1251, a substrate 252, a mirror layer 253, a first optical member 254, a second optical member 255, a third optical member 256, a second phosphor layer 1258, a translucent member 259, and a light emitting section 260.

[0110] In this embodiment, the first phosphor layer 1251 is made of a different phosphor material from the first phosphor layer 251 of the first embodiment. The first phosphor layer 1251 converts the excitation light EL into fluorescent light (second light) GL, which is green light having a green wavelength band of 500 to 570 nm, different from the blue wavelength band. The second phosphor layer 1258 converts the excitation light EL into fluorescent light (third light) RL, which is red light having a red wavelength band of 600 to 800 nm, different from the blue wavelength band. In this embodiment, the red wavelength band (third wavelength band) of the fluorescent light RL emitted by the second phosphor layer 1258 is wider than the green wavelength band (second wavelength band) of the fluorescent light GL emitted by the first phosphor layer 1251 and the blue wavelength band (first wavelength band) of the excitation light EL emitted by the light source 250.

[0111] Such a green phosphor is, for example, Lu3Al5O 12 : Ce3+ phosphor, Y3O4:Eu 2+ (Ba,Sr)2SiO4:Eu phosphor 2+ Ba3Si6O phosphor 12 N2:Eu 2+ (Si,Al)6(O,N)8:Eu phosphor 2+ Phosphor materials such as ZnO-based phosphors are used.

[0112] In this embodiment, the degree of light scattering in second phosphor layer 1258 is smaller than the degree of light scattering in first phosphor layer 1251. In this embodiment, the number of scatterers contained in second phosphor layer 1258 is smaller than the number of scatterers contained in first phosphor layer 1251.

[0113] Also in this embodiment, by making the thickness of the second phosphor layer 1258 smaller than the thickness of the first phosphor layer 1251, the fluorescence conversion efficiency in the second phosphor layer 1258 is reduced, making it easier to transmit the excitation light EL.

[0114] According to the light source device 225 of this embodiment described above, the fluorescence RL generated by exciting the second phosphor layer 1258 with the excitation light EL emitted from the light source 250, the fluorescence GL generated by exciting the first phosphor layer 1251 with the excitation light EL emitted from the second phosphor layer 1258 without being used to excite the fluorescence RL, and a portion of the excitation light EL emitted from the light source 250 without being used to excite the fluorescence RL and GL can be extracted as illumination light WL2 from the light emission section 260.

[0115] The light source device 225 of this embodiment uses fluorescence GL, which is green light generated by the first phosphor layer 1251, fluorescence RL, which is red light generated by the second phosphor layer 1258, and a portion of the excitation light EL, which is blue light, so that it is possible to generate illumination light WL2 with high color reproducibility for each of the RGB colors. Therefore, a projector equipped with the light source device 225 of this embodiment can project an image with high brightness and high reproducibility of each of the RGB colors.

[0116] Although one embodiment of the present invention has been described as an example, the present invention is not necessarily limited to the above embodiment, and various modifications can be made within the scope that does not deviate from the spirit of the present invention.

[0117] For example, in the first embodiment, the case where the light source 250 is disposed in the notch 251K formed in the first phosphor layer 251 is taken as an example, but the layout of the light source and the first phosphor layer is not limited to this.

[0118] (First Modification) FIG. 8 is a plan view of a first phosphor layer according to a first modified example. 8, the first phosphor layer 51 of this modification is composed of a first portion 51A and a second portion 51B that are spaced apart from each other. The first portion 51A and the second portion 51B are each composed of the same phosphor material as the first phosphor layer 251 of the first embodiment. In this modification, the light source 250 is disposed between the first portion 51A and the second portion 51B. The light source 250 is disposed in a recess 261 formed in the support surface 2521. According to this configuration, there is no need to place the light source 250 within the cutout portion 251K as in the first embodiment, and the first portion 51A and the second portion 51B can be placed so as to sandwich the light source 250, making it easier to align the first phosphor layer 51 and the light source 250. In the configurations of the second and third embodiments, the first phosphor layer may be configured with two portions, and the light source 250 may be disposed between the two portions.

[0119] In the above embodiment, the light source 250 is disposed in the recess 261 formed in the substrate 252 , but the light source 250 may also be disposed on the support surface 2521 of the substrate 252 .

[0120] (Second Modification) FIG. 9 is a cross-sectional view showing a schematic configuration of a light source device according to a second modified example. As shown in FIG. 9, the light source device 25A of this modified example includes a light source 250, a first phosphor layer 251, a substrate 252, a mirror layer 253, a first optical member 254, a second optical member 255, a third optical member 256, a second phosphor layer 258, and a light emitting section 260.

[0121] In light source device 25A of this modification, light source 250 and first phosphor layer 251 are arranged side by side in the X-axis direction on support surface 2521. Specifically, light source 250 is arranged on the opposite side of first phosphor layer 251 from light emitting section 260.

[0122] According to this configuration, the light source 250 is disposed on the opposite side to the light emitting portion 260, and therefore the excitation light EL emitted from the light source 250 does not enter the second phosphor layer 258 disposed on the first optical member 254 and is not directly emitted from the light emitting portion 260. Therefore, similar to the first embodiment, bright illumination light WL can be emitted from the light emitting portion 260.

[0123] In addition, in the above embodiment, an example was given of a case where the amount of scatterer and thickness of the second phosphor layer 258, 1258 are reduced compared to the first phosphor layer 251, 1251, thereby suppressing the amount of fluorescence conversion in the second phosphor layer 258, 1258 and making it easier to transmit the excitation light EL, but the amount of fluorescence conversion may also be controlled by adjusting only either the amount of scatterer or the thickness of the second phosphor layer 258, 1258.

[0124] In addition, in the above embodiment, an example was given in which the light emitting portion 260 is formed by the substrate 252, the first optical member 254, the second optical member 255, and the third optical member 256, but the light emitting portion may also be formed by at least the substrate 252 and the first optical member 254.

[0125] Furthermore, in the above embodiment, an example was given in which the first optical member 254, the second optical member 255, and the third optical member 256 are each made up of separate members, but the first optical member 254, the second optical member 255, and the third optical member 256 may also be integrally formed from a single member.

[0126] Furthermore, in the above embodiment, an example has been given in which the width in the Z direction of the first phosphor layer 251 is narrower than the width in the Z direction of the support surface 2521 located in the storage space that stores the first phosphor layer 251. However, the width in the Z direction of the back surface 2513 of the first phosphor layer 251 may be the same as the width in the Z direction of the support surface 2521. In this case, the side surface 2512 of the first phosphor layer 251 is in contact with the second optical member 255 and the third optical member 256, and therefore the fluorescence YL emitted from the side surface 2512 is reflected by the second optical member 255 and the third optical member 256 and returned into the first phosphor layer 251. Similarly, although an example has been given in which the Z-direction width of the second phosphor layer 258 is narrower than the Z-direction width of the first optical member 254, the Z-direction width of the second phosphor layer 258 may be the same as the Z-direction width of the first optical member 254.

[0127] In the above embodiment, the projector 1 is provided with three light modulation devices 4R, 4G, and 4B, but the present invention can also be applied to a projector that displays color images using one light modulation device. Furthermore, the light modulation device is not limited to the liquid crystal panel described above, and a digital mirror device, for example, can also be used.

[0128] Furthermore, in the above embodiment, the light source device according to the present invention is applied to a projector, but the present invention is not limited to this. The light source device according to the present invention can also be applied to lighting fixtures such as automobile headlights.

[0129] The light source device according to the aspect of the present invention may have the following configuration. A light source device according to one aspect of the present invention includes a substrate having a support surface, a light source disposed on the support surface side and emitting first light in a first wavelength band, a first optical member having a first optical layer facing the support surface and reflecting the first light emitted from the light source, a first wavelength conversion layer disposed on the support surface and having a light incident surface onto which the first light is incident and converting the first light into second light in a second wavelength band different from the first wavelength band, and a second wavelength conversion layer disposed on the first wavelength conversion layer side of the first optical layer and converting the first light into second light in a second wavelength band different from the first wavelength band. the first optical layer is inclined with respect to the light incident surface and further reflects the second light and the third light; the second wavelength conversion layer converts a portion of the first light emitted from the light source into the third light; the first wavelength conversion layer converts a portion of the first light emitted from the second wavelength conversion layer into the second light; and the light emitting portion emits the first light, the second light, and the third light.

[0130] In the light source device according to one aspect of the present invention, the third wavelength band may be the second wavelength band.

[0131] In one embodiment of the light source device of the present invention, the first light may be blue light, the second light and the third light may be yellow light, and the light emitting section may emit white illumination light including the first light, the second light, and the third light.

[0132] In the light source device according to one aspect of the present invention, the third waveband may be wider than the first waveband and the second waveband.

[0133] In one embodiment of the light source device of the present invention, the first light may be blue light, the second light may be yellow light, and the third light may be red light, and the light emitting section may emit white illumination light including the first light, the second light, and the third light.

[0134] In one embodiment of the light source device of the present invention, the first light may be blue light, the second light may be green light, and the third light may be red light, and the light emitting section may emit white illumination light including the first light, the second light, and the third light.

[0135] In the light source device according to one aspect of the present invention, the thickness of the second wavelength conversion layer may be smaller than the thickness of the first wavelength conversion layer.

[0136] In the light source device according to one aspect of the present invention, the degree of scattering of light in the second wavelength conversion layer may be smaller than the degree of scattering of light in the first wavelength conversion layer.

[0137] In the light source device according to one aspect of the present invention, the light source may be arranged on the opposite side of the first wavelength conversion layer from the light emitting portion.

[0138] In the light source device according to one aspect of the present invention, the first wavelength conversion layer may have a cutout portion formed by cutting out a portion thereof, and the light source may be disposed in the cutout portion of the first wavelength conversion layer.

[0139] In one embodiment of the light source device of the present invention, the first wavelength conversion layer may include a first portion and a second portion spaced apart from each other, and the light source may be disposed between the first portion and the second portion.

[0140] In one embodiment of the light source device of the present invention, the light source may be configured to have a light-emitting element that emits a first light, a substrate that supports the light-emitting element, and a reflective layer provided between the substrate and the light-emitting element.

[0141] The light source device according to one aspect of the present invention may further include a light-transmitting member provided in contact with the light-emitting side of the light source.

[0142] In the light source device according to one aspect of the present invention, the light-transmitting member may have a second optical layer provided on the opposite side to the light source, the second optical layer transmitting the first light and reflecting the second light and the third light.

[0143] In one embodiment of the light source device of the present invention, the substrate may have a recess formed on the support surface, the light source may be disposed in the recess of the substrate, and the surface of the translucent member facing the first optical member may be flush with the light incident surface of the first wavelength conversion layer.

[0144] In one embodiment of the light source device of the present invention, the light source device may further include a second optical element having a third optical layer that reflects the first light, the second light, and the third light, and being arranged so that the third optical layer intersects with the support surface and the first optical layer, and a third optical element having a fourth optical layer that reflects the first light, the second light, and the third light, and being arranged so that the fourth optical layer intersects with the support surface and the first optical layer and faces the third optical layer, and the light exit portion may be configured to be formed by the substrate, the first optical element, the second optical element, and the third optical element.

[0145] A projector according to one aspect of the invention may have the following configuration. A projector according to one aspect of the present invention comprises a light source device according to the above aspect of the present invention, a light modulation device that modulates light from the light source device in accordance with image information, and a projection optical device that projects the light modulated by the light modulation device. [Explanation of symbols]

[0146] 1...Projector, 4B, 4G, 4R...Light modulation device, 6...Projection optical device, 25, 25A, 125, 225...Light source device, 51A...First part, 51B...Second part, 250...Light source, 250a...Light emitting element, 250b, 2541, 2551, 2561...Base material, 250c...Reflective layer, 251, 1251...First phosphor layer (first wavelength conversion layer), 251K...Notch portion, 252...Substrate, 254...First optical member, 255...Second optical member, 256...Third optical member, 258, 1258...second phosphor layer (second wavelength conversion layer), 259...translucent member, 260...light emitting portion, 261...recess, 2511, 2581...surface (light incident surface), 2521...support surface, 2542...first optical layer, 2552...third optical layer, 2562...fourth optical layer, 2592...second optical layer, EL...excitation light (first light), GL, YL...fluorescence (second light), H1, H2...thickness, LB...blue light, LG...green light, LR...red light, RL...fluorescence (third light), WL, WL1, WL2...illumination light.

Claims

1. a substrate having a support surface; a light source disposed on the support surface side and configured to emit first light in a first wavelength band; a first optical layer facing the support surface and reflecting the first light emitted from the light source; a first optical member; a light incident surface on which the first light is incident, the light incident surface being disposed on the support surface, a first wavelength conversion layer that converts the first light into a second light of a second wavelength band different from the first wavelength band; a first wavelength conversion layer disposed on the first optical layer and converting the first light into the first wavelength conversion layer; a second wavelength conversion layer that converts the third light into a third waveband different from the long waveband; a light emitting portion formed by at least the substrate and the first optical member and emitting light; 、 Equipped with The first optical layer is inclined with respect to the light incident surface and transmits the second light and the third light. reflected in The second wavelength conversion layer converts a part of the first light emitted from the light source into the third light. death, The first wavelength conversion layer converts a part of the first light emitted from the second wavelength conversion layer into the Converted into two lights, the light emitting unit emits the first light, the second light, and the third light; the thickness of the second wavelength conversion layer is smaller than the thickness of the first wavelength conversion layer; A light source device characterized by:

2. the third wavelength band is the second wavelength band; 2. The light source device according to claim 1.

3. the first light is blue light, and the second light and the third light are yellow light; The light emitting unit emits white illumination light including the first light, the second light, and the third light. do, 3. The light source device according to claim 2.

4. A substrate having a support surface; a light source disposed on the support surface side and configured to emit first light in a first wavelength band; a first optical layer facing the support surface and reflecting the first light emitted from the light source; a first optical member; a light incident surface on which the first light is incident, the light incident surface being disposed on the support surface, a first wavelength conversion layer that converts the first light into a second light of a second wavelength band different from the first wavelength band; a first wavelength conversion layer disposed on the first optical layer and converting the first light into the first wavelength conversion layer; a second wavelength conversion layer that converts the third light into a third waveband different from the long waveband; a light emitting portion formed by at least the substrate and the first optical member and emitting light; 、 Equipped with The first optical layer is inclined with respect to the light incident surface and transmits the second light and the third light. reflected in The second wavelength conversion layer converts a part of the first light emitted from the light source into the third light. death, The first wavelength conversion layer converts a part of the first light emitted from the second wavelength conversion layer into the Converted into two lights, the light emitting unit emits the first light, the second light, and the third light; The wavelength of the third waveband is greater than the wavelength of the first waveband and the wavelength of the second waveband. Kii, A light source device characterized by:

5. the first light is blue light, the second light is yellow light, and the third light is red light; The light emitting unit emits white illumination light including the first light, the second light, and the third light. do, 5. The light source device according to claim 4.

6. the first light is blue light, the second light is green light, and the third light is red light; The light emitting unit emits white illumination light including the first light, the second light, and the third light. do, 5. The light source device according to claim 4.

7. A substrate having a support surface; a light source disposed on the support surface side and configured to emit first light in a first wavelength band; a first optical layer facing the support surface and reflecting the first light emitted from the light source; a first optical member; a light incident surface on which the first light is incident, the light incident surface being disposed on the support surface, a first wavelength conversion layer that converts the first light into a second light of a second wavelength band different from the first wavelength band; a first wavelength conversion layer disposed on the first optical layer and converting the first light into the first wavelength conversion layer; a second wavelength conversion layer that converts the third light into a third waveband different from the long waveband; a light emitting portion formed by at least the substrate and the first optical member and emitting light; 、 Equipped with The first optical layer is inclined with respect to the light incident surface and transmits the second light and the third light. reflected in The second wavelength conversion layer converts a part of the first light emitted from the light source into the third light. death, The first wavelength conversion layer converts a part of the first light emitted from the second wavelength conversion layer into the Converted into two lights, the light emitting unit emits the first light, the second light, and the third light; The degree of light scattering in the second wavelength conversion layer is Less than the degree A light source device characterized by:

8. the light source is disposed on the opposite side of the first wavelength conversion layer from the light emitting portion. The light source device according to claim 1 .

9. the first wavelength conversion layer has a notched portion formed by cutting out a portion thereof, the light source is disposed in the cutout portion of the first wavelength conversion layer.

8. The light source device according to claim 1, wherein the light source device is a light source unit.

10. the first wavelength conversion layer includes a first portion and a second portion spaced apart from each other; The light source is disposed between the first portion and the second portion.

8. The light source device according to claim 1, wherein the light source device is a light source unit.

11. The light source includes a light emitting element that emits the first light, a substrate that supports the light emitting element, and A reflective layer provided between the substrate and the light-emitting element.

11. The light source device according to claim 1, wherein the light source device is a light source unit.

12. Further, a light-transmitting member is provided in contact with the light emitting side of the light source.

12. The light source device according to claim 1, wherein the light source device is a light source unit.

13. The light-transmitting member is provided on the opposite side of the light source and transmits the first light and the second light. a second optical layer that reflects the third light; 13. The light source device according to claim 12.

14. the substrate has a recess formed in the support surface; the light source is disposed in the recess of the substrate; The surface of the light-transmitting member on the side of the first optical member is in plane with the light incident surface of the first wavelength conversion layer. One, 14. The light source device according to claim 12 or 13.

15. a third optical layer that reflects the first light, the second light, and the third light, a second optical element having a layer disposed across the support surface and the first optical layer; a fourth optical layer that reflects the first light, the second light, and the third light, a layer disposed across the support surface and the first optical layer and facing the third optical layer; and a third optical member, The light exiting portion includes the substrate, the first optical member, the second optical member, and the third optical member. formed by the member, 15. The light source device according to claim 1, wherein the light source device is a light source unit.

16. a light source device according to any one of claims 1 to 15; a light modulation device that modulates light from the light source device; a projection optical device that projects the light modulated by the light modulation device, A projector characterized by:

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