Light source device and projector

Abstract

To provide a light source device and a projector capable of increasing light use efficiency of fluorescence.SOLUTION: A light source device includes: a substrate having a supporting surface; a first light source disposed at a supporting surface side of the substrate and 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 first light source; a first wavelength conversion layer having a light incident surface on which the first light emitted from the first light source is incident, converting the first light into second light in a second wavelength range different from the first wavelength range, and emitting the second light from the light incident surface; a light emitting portion formed by at least the substrate and the first optical member and emitting light; and a second optical member disposed at the light emitting portion and having a second optical layer that reflects the first light and transmits the second light. The first optical layer is inclined with respect to the light incident surface and reflects the second light. The first wavelength conversion layer is disposed on a surface of the substrate side of the first optical layer or the supporting surface of the substrate. The light emitting portion emits the second 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, light source devices have been proposed that generate illumination light using fluorescence emitted from a phosphor when the phosphor is irradiated with excitation light emitted from a light source. For example, Patent Document 1 listed below discloses a light source device that uses a reflective phosphor wheel that emits fluorescence from a surface onto which excitation light is incident. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Publication No. 2018-013764 Summary of the Invention [Problem to be solved by the invention]

[0004] However, in the above light source device, the efficiency of extracting the fluorescence emitted by the phosphor is insufficient, and therefore the fluorescence cannot be used efficiently as illumination light, resulting in a problem of reduced light utilization efficiency of the fluorescence. [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 method for manufacturing a substrate having a support surface, a first light source disposed on the support surface side of the substrate and emitting first light in a first wavelength band; a first optical layer facing the support surface and reflecting the first light emitted from the first light source; an optical member and a light incident surface on which the first light emitted from the first light source is incident, converting the first light into second light in a second wavelength band different from the first wavelength band, and converting the second light into the light incident a first wavelength conversion layer for emitting light from a surface thereof, and a first optical member formed by at least the substrate and the first optical member; a light emitting portion that emits light, and a second optical layer that reflects the first light and transmits the second light. and a second optical member disposed in the light exit portion, and the first optical layer support Hold the first wavelength conversion layer is inclined with respect to the surface and reflects the second light, the optical element is disposed on one of the surface of the optical layer facing the substrate and the support surface of the substrate; A light source device is provided, in which the emission section emits the second light.

[0006] According to a second aspect of the present invention, there is provided a projector comprising the light source device of the first aspect of the present invention, an optical modulation device that modulates light from the light source device, and a projection optical device that projects the light modulated by the optical 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 configuration diagram of a first 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 diagram illustrating a configuration of a light source device according to a fourth embodiment. [Figure 9] FIG. 10 is a diagram showing the configuration of a light source device according to a first modified example. [Figure 10] FIG. 10 is a diagram showing the 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, a first illumination device 20, and a second illumination device 21.

[0010] The color separation optical system 3 separates the yellow illumination light WL from the first illumination device 20 into red light LR and green light LG. The color separation optical system 3 includes a dichroic mirror 7, a first reflecting mirror 8a, and a second reflecting mirror 8b.

[0011] The dichroic mirror 7 separates the illumination light WL into red light LR and green light LG. Of the illumination light WL, the dichroic mirror 7 transmits the red light LR and reflects the green light LG. The second reflecting mirror 8b reflects the green light LG toward the optical modulation device 4B. The first reflecting mirror 8a is disposed in the optical path of the red light LR and reflects the red light LR that has transmitted through the dichroic mirror 7 toward the optical modulation device 4R.

[0012] On the other hand, the blue light LB from the second illumination device 21 is reflected by the reflecting mirror 9 toward the light modulation device 4B.

[0013] Here, the configuration of the second illumination device 21 will be described. The second illumination device 21 includes a light source 81, a condenser lens 82, a diffuser 83, a rod lens 84, and a relay lens 85. The light source 81 is composed of at least one semiconductor laser and emits blue light LB made of laser light. Note that the light source 81 is not limited to a semiconductor laser, and may be an LED that emits blue light.

[0014] The condenser lens 82 is a convex lens, and causes the blue light LB to be incident on the diffuser plate 83 in a substantially condensed state. The diffuser plate 83 diffuses the blue light LB from the light source 81 with a predetermined degree of diffusion, thereby generating blue light LB having a uniform luminous intensity distribution similar to that of the illumination light WL emitted from the first lighting device 20. The diffuser plate 83 may be, for example, frosted glass made of optical glass.

[0015] The blue light LB diffused by the diffuser plate 83 enters the rod lens 84. The rod lens 84 is a rectangular column extending along the illumination optical axis ax2 of the second illumination device 21, and has an incident end surface 84a at one end and an exit end surface 84b at the other end. The diffuser plate 83 is fixed to the incident end surface 84a of the rod lens 84 via an optical adhesive (not shown). It is desirable that the refractive index of the diffuser plate 83 and the refractive index of the rod lens 84 match as closely as possible.

[0016] The blue light LB propagates through the rod lens 84 by total reflection, and is emitted from the emission end surface 84b with improved uniformity of illuminance distribution. The blue light LB emitted from the rod lens 84 is incident on the relay lens 85. The relay lens 85 causes the blue light LB, whose uniformity of illuminance distribution has been improved by the rod lens 84, to be incident on the reflecting mirror 9.

[0017] The shape of the exit end surface 84b of the rod lens 84 is a rectangle that is approximately similar to the shape of the image forming area of ​​the light modulation device 4B, so that the blue light LB emitted from the rod lens 84 is efficiently incident on the image forming area of ​​the light modulation device 4B.

[0018] 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.

[0019] 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.

[0020] 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.

[0021] 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.

[0022] 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.

[0023] FIG. 2 is a schematic diagram of the first illumination device 20. As shown in FIG. As shown in FIG. 2, the first illumination device 20 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.

[0024] The light source device 25 emits yellow illumination light WL toward the pickup optical system .

[0025] 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.

[0026] 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.

[0027] As shown in Figures 3 to 5, the light source device 25 of this embodiment includes a light source (first light source) 250, a phosphor layer (first wavelength conversion layer) 251, a substrate 252, a mirror layer 253, a first optical member 254, a second optical member 257, a third optical member 255, a fourth optical member 256, a translucent member 259, and a light emitting section 260. The light emitting portion 260 of this embodiment is an opening formed in each end surface on the +Y side of the substrate 252, the first optical member 254, the third optical member 255, and the fourth optical member 256. The light emitting portion 260 emits the fluorescence generated in the phosphor layer 251.

[0028] The light source 250 includes 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, specifically on a surface 250b1 that is the surface of the base material 250b facing the light-emitting element 250a. The reflective layer 250c is configured as, for example, a metal layer or a dielectric layer.

[0029] The substrate 252 has a support surface 2521 that supports the 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 the surface 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.

[0030] The phosphor layer 251 is a plate-shaped phosphor having 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 EL emitted from the first optical member 254 is incident on the surface 2511 of the phosphor layer 251, as will be described later.

[0031] The phosphor layer 251 includes phosphor particles that are excited by the excitation light EL 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 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 phosphor layer 251 includes a plurality of scatterers. Pores or transparent particles with a refractive index different from that of the phosphors are used as the scatterers. In this embodiment, pores are used as the scatterers.

[0032] The substrate 252 is thermally connected to the phosphor layer 251. Since the substrate 252 is thermally connected to the phosphor layer 251, the substrate 252 cools the phosphor layer 251 by dissipating heat from the phosphor layer 251.

[0033] The phosphor layer 251 of this embodiment has a cutout portion 251K that is a portion that has been cut out. The cutout portion 251K is provided in a state that it penetrates the phosphor layer 251, and therefore, a portion of the substrate 252 is exposed.

[0034] The 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.

[0035] The mirror layer 253 is provided between the substrate 252 and the phosphor layer 251. The area of ​​the mirror layer 253 is larger than the area of ​​the back surface 2513 of the phosphor layer 251. The mirror layer 253 is provided at least around the phosphor layer 251 on the support surface 2521 of the substrate 252. The 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 part of the mirror layer 253 may be formed directly on the back surface 2513 of the phosphor layer 251.

[0036] 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 phosphor layer 251. The first optical member 254 is disposed so as not to come into contact with the phosphor layer 251.

[0037] The first optical member 254 is disposed in a state inclined with respect to the surface 2511 of the phosphor layer 251. The angle that the first optical member 254 forms with respect to the surface 2511 of the phosphor layer 251 is set to an acute angle.

[0038] 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 not only the excitation light EL from the light source 250 but also fluorescence YL (second light) described below.

[0039] In this embodiment, the phosphor layer 251 converts the excitation light EL emitted from the light source 250 and reflected by the first optical layer 2542 of the first optical member 254 into fluorescence YL, which is emitted from the surface 2511.

[0040] 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 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.

[0041] In this embodiment, the surface 259a of the light-transmitting member 259 on the first optical member 254 side is flush with the surface 2511 of the phosphor layer 251. In other words, the surface 259a of the light-transmitting member 259 and the surface 2511 of the phosphor layer 251 are arranged on the same plane in the direction along the normal to the support surface 2521 of the substrate 252.

[0042] The light-transmitting member 259 includes a light-transmitting substrate 2591 and a third optical layer 2592. The light-transmitting substrate 2591 is made of a light-transmitting member such as alumina, sapphire, or glass. The third 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 third 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 by the phosphor layer 251. 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.

[0043] The third optical member 255 includes a base material 2551 and a fourth 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 fourth optical layer 2552 is formed on the inner surface of the base material 2551. The fourth optical layer 2552 is made of, for example, a dielectric multilayer film or a metal film.

[0044] The third optical member 255 is disposed so as to intersect the support surface 2521 of the substrate 252 and the first optical member 254. The third optical member 255 is disposed so that the fourth optical layer 2552 intersects the support surface 2521 and the first optical layer 2542. The third optical member 255 may be perpendicular to the support surface 2521 of the substrate 252 and the first optical member 254. The fourth optical layer 2552 may be perpendicular to the support surface 2521 and the first optical layer 2542. The third optical member 255 is disposed so that its thickness direction coincides with the Y-axis direction. The third optical member 255 is disposed near the +Y side of the phosphor layer 251. Therefore, a portion of the fluorescence YL emitted from the phosphor layer 251 toward the +Y side is reflected by the fourth optical layer 2552 of the third optical member 255. The third optical member 255 reflects not only the fluorescence YL but also the excitation light EL.

[0045] The third optical member 255 is in the shape of a trapezoidal plate. As shown in FIG. 3 , the third 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.

[0046] 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, third optical member 255 is formed in a trapezoidal plate shape, which eliminates the need for chamfering, thereby improving the workability of base material 2551.

[0047] In this embodiment, a portion of the third optical member 255 is embedded in the substrate 252. Therefore, the third optical member 255 is firmly supported by the substrate 252. A part of the end portion on the +X side of the third optical member 255 is fitted into a groove 2524 formed in the support surface 2521 of the substrate 252. The gap between the third optical member 255 and the groove 2524 may be filled with an adhesive.

[0048] Specifically, the third optical member 255 has the entire first end face 55a and the entire third end face 55c and a part of the second end face 55b fitted in the groove 2524. An end 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 of the substrate 252.

[0049] The fourth optical member 256 has a configuration similar to that of the third optical member 255 . That is, the fourth optical member 256 includes a base material 2561 and a fifth optical layer 2562. The fifth optical layer 2562 is formed on the inner surface of the base material 2561.

[0050] The fourth 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 third optical member 255. The fourth optical member 256 is disposed so that the fifth optical layer 2562 intersects the support surface 2521 and the first optical layer 2542 and faces the fourth optical layer 2552. The fourth optical member 256 may be perpendicular to the support surface 2521 of the substrate 252 and the first optical member 254. The fifth optical layer 2562 may be perpendicular to the support surface 2521 and the first optical layer 2542. The fourth optical member 256 is disposed so that its thickness direction coincides with the Y-axis direction. The fourth optical member 256 is disposed near the -Y side of the phosphor layer 251. Therefore, the fluorescence YL that is emitted from the phosphor layer 251 toward the −Y side and enters the fourth optical member 256 is reflected by the fifth optical layer 2562 of the fourth optical member 256. The fourth optical member 256 reflects the excitation light EL in addition to the fluorescence YL.

[0051] The fourth optical member 256 is a trapezoidal plate similar to the third optical member 255 . The fourth 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.

[0052] In this embodiment, a portion of the fourth optical member 256 is embedded in the substrate 252, so that the fourth optical member 256 is firmly supported by the substrate 252. A part of the end portion on the +X side of the fourth optical member 256 is fitted into a groove 2524 formed in the support surface 2521 of the substrate 252. The gap between the fourth optical member 256 and the groove 2524 may be filled with an adhesive.

[0053] Specifically, the fourth 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 end 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 of the substrate 252.

[0054] In this embodiment, the first optical member 254 is supported by the third optical member 255 and the fourth optical member 256. The first optical member 254 is fixed to the third optical member 255 and the fourth optical member 256 by adhesive. Specifically, the first optical member 254 is provided to bridge between the fourth end surface 55d of the third optical member 255 and the fourth end surface 56d of the fourth 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.

[0055] Based on this configuration, light source device 25 of this embodiment closes the -X side with substrate 252, first optical member 254, third optical member 255, and fourth optical member 256, and forms light emitting portion 260 on the +X side. Therefore, light source device 25 prevents light leakage from the fluorescence YL on the side opposite to light emitting portion 260, and can efficiently emit light from light emitting portion 260.

[0056] In the light source device 25 of this embodiment, the second optical member 257 is disposed so as to cover the light exit portion 260. The second optical member 257 includes a light-transmitting substrate 2571 and a second optical layer 2572. The light-transmitting substrate 2571 is made of, for example, a thin glass plate. The second optical layer 2572 is made of, for example, a dichroic layer that transmits fluorescence (second light) YL having a yellow wavelength band (second wavelength band) of 550 to 640 nm and reflects light in the blue wavelength band including the excitation light EL. Therefore, the light emitting section 260 can selectively extract the yellow light containing the fluorescence YL as the illumination light WL by the second optical member 257.

[0057] In the light source device 25 of this embodiment, the phosphor layer 251 is accommodated in an accommodation space S surrounded by a substrate 252, a first optical member 254, a second optical member 257, a third optical member 255, and a fourth optical member 256. The accommodation space S is provided with, for example, an air layer AR.

[0058] The light source 250 emits excitation light EL using Lambertian luminescence. The excitation light EL emitted from the light source 250 using Lambertian luminescence is incident on a first optical member 254 disposed opposite the light source 250 and is reflected by a first optical layer 2542 of the first optical member 254 toward a support surface 2521 of the substrate 252. The excitation light EL reflected by the first optical layer 2542 is incident on a phosphor layer 251 provided on the support surface 2521. The phosphor layer 251 converts the wavelength of the excitation light EL to generate fluorescence YL, which is emitted from a surface 2511. At least a portion of the fluorescence YL emitted from the phosphor layer 251 passes through a second optical member 257 covering the light emitting unit 260 and is emitted as illumination light WL.

[0059] Furthermore, a portion of the excitation light EL reflected by the first optical layer 2542 travels toward the light emitting portion 260 and is reflected by the second optical layer 2572 of the second optical member 257 that covers the light emitting portion 260. The excitation light EL reflected by the second optical layer 2572 eventually enters the phosphor layer 251 and is used to excite the fluorescence YL.

[0060] Furthermore, a portion of the excitation light EL reflected by the first optical layer 2542 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 a portion of the excitation light EL reflected by the mirror layer 253 is reflected by the second optical layer 2572 of the second optical member 257, and eventually enters the phosphor layer 251 and is used to excite the fluorescence YL.

[0061] Furthermore, a portion of the excitation light EL reflected by the first optical layer 2542 enters the light-transmitting member 259, passes through a third 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 EL that has passed through the third 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 first optical member 254. Then, the excitation light EL is reflected by the first optical layer 2542 of the first optical member 254 and is reused for exciting the phosphor layer 251.

[0062] Furthermore, a portion of the fluorescence YL emitted from the phosphor layer 251 is reflected by the first optical member 254 of the first optical member 254, passes through the second optical member 257, and is emitted from the light emitting portion 260. Note that a portion of the fluorescence YL reflected by the first optical member 254 and incident on the phosphor layer 251 passes through the phosphor layer 251 and is reflected by the mirror layer 253, passes through the second optical member 257, and is emitted from the light emitting portion 260.

[0063] Furthermore, a portion of the fluorescence YL emitted from the phosphor layer 251 passes through the mirror layer 253 and enters the third optical member 255 or the fourth optical member 256, or directly enters the third optical member 255 or the fourth optical member 256. Then, at least a portion of the fluorescence YL reflected by the third optical member 255 or the fourth optical member 256 passes through the second optical member 257 and is emitted from the light emitting portion 260.

[0064] A portion of the excitation light EL reflected by the first optical member 254 propagates in the opposite direction (-Y side) to the light emitting portion 260, but after repeated reflections, it eventually enters the phosphor layer 251 and is used to excite the fluorescence YL. Furthermore, a part of the fluorescence YL emitted from the phosphor layer 251 propagates in the opposite direction (−Y side) to the light emitting portion 260, but is eventually emitted from the light emitting portion 260 by repeated reflection.

[0065] In this way, in the light source device 25 of this embodiment, the excitation light EL emitted from the light source 250 can be efficiently incident on the phosphor layer 251, and the illumination light WL containing the fluorescence YL generated in the phosphor layer 251 can be emitted from the light emission section 260.

[0066] In the light source device 25 of this embodiment, in the phosphor layer 251, heat is more likely to build up 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 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 phosphor layer 251 opposite to the light emission section 260, where heat is more likely to build up. Therefore, the phosphor layer 251 can be efficiently cooled.

[0067] 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.

[0068] 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.

[0069] 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.

[0070] 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.

[0071] 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.

[0072] The light source device 25 according to the present embodiment described above provides the following effects. The light source device 25 of this embodiment includes 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 phosphor layer 251 having a surface 2511 on which the excitation light EL emitted from the light source 250 is incident, converting the excitation light EL into fluorescence YL and emitting the fluorescence YL from the surface 2511, a light emitting section 260 formed by at least the substrate 252 and the first optical member 254 and emitting illumination light WL, and a second optical member 257 arranged on the light emitting section 260 and having a second optical layer 2572 that reflects the excitation light EL and transmits the fluorescence YL. The first optical layer 2542 is inclined relative to the surface 2511 and reflects the fluorescent light YL, and the phosphor layer 251 is disposed on the support surface 2521 of the substrate 252 .

[0073] According to the light source device 25 of this embodiment, the fluorescence YL can be efficiently extracted as illumination light WL by the second optical member 257 arranged in the light emitting section 260. Furthermore, the excitation light EL emitted toward the light emitting section 260 is made to re-enter the phosphor layer 251 by the second optical member 257, thereby increasing the conversion efficiency of the fluorescence YL. Therefore, according to the light source device 25 of this embodiment, bright illumination light WL can be emitted from the light emitting portion 260 by increasing the light utilization efficiency of the fluorescence YL.

[0074] The light source device 25 of this embodiment can reduce the etendue by emitting the illumination light WL from the light emitting portion 260. In the light source device 25 of this embodiment, the etendue can be reduced without reducing the incident area of ​​the excitation light on the phosphor layer 251, so the light density of the excitation light EL does not increase in the phosphor layer 251. Therefore, a decrease in the fluorescence conversion efficiency due to an increase in light density is suppressed, and bright fluorescence YL can be extracted as the illumination light WL.

[0075] In the light source device 25 of this embodiment, the phosphor layer 251 has a cutout portion 251K formed by cutting out a part of the phosphor layer 251, and the light source 250 is disposed in the cutout portion 251K of the phosphor layer 251.

[0076] According to this configuration, the light source 250 can be arranged at a desired position on the support surface 2521 without interfering with the phosphor layer 251. This increases the degree of freedom in the layout of the light source 250 on the substrate 252.

[0077] 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 provided on the light-emitting element 250a side of the base material 250b.

[0078] 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.

[0079] 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 third optical layer 2592 provided on the opposite side to the light source 250, which transmits the excitation light EL and reflects the fluorescence YL.

[0080] 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 by the third optical layer 2592 and emit the reflected fluorescence YL from the light emitting portion 260. This can further increase the light utilization efficiency of the fluorescence YL.

[0081] In the light source device 25 of this embodiment, the light source 250 is arranged in a recess 261 formed in the support surface 2521 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 phosphor layer 251.

[0082] 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 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.

[0083] The light source device 25 of this embodiment further includes: a third optical member 255 having a fourth optical layer 2552 that reflects the excitation light EL and the fluorescence YL, and arranged so that the fourth optical layer 2552 intersects the support surface 2521 and the first optical layer 2542; and a fourth optical member 256 having a fifth optical layer 2562 that reflects the excitation light EL and the fluorescence YL, and arranged so that the fifth optical layer 2562 intersects the support surface 2521 and the first optical layer 2542 and faces the fourth optical layer 2552. The light output unit 260 is formed by the substrate 252, the first optical member 254, the third optical member 255, and the fourth optical member 256.

[0084] According to this configuration, light leakage from other than the light emitting portion 260 is suppressed, so that the illumination light WL can be emitted from the light emitting portion 260 efficiently.

[0085] 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.

[0086] (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.

[0087] 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 phosphor layer 251, a substrate 252, a mirror layer 253, a first optical member 254, a second optical member 257, a third optical member 255, a fourth optical member 256, and a light emitting section 260.

[0088] In this embodiment, the light source 250 is disposed on the support surface 2521 of the substrate 252. That is, no recess is formed in the support surface 2521 of the substrate 252. A mirror layer 253 is formed between the light source 250 and the support surface 2521. The phosphor layer 251 is disposed on the inner surface (surface on the substrate 252 side) 2542a of the first optical layer 2542. In this embodiment, the phosphor layer 251 is disposed opposite the light source 250.

[0089] The excitation light EL emitted from the light source 250 is incident on the phosphor layer 251 disposed opposite the light source 250. The phosphor layer 251 converts the wavelength of the excitation light EL to generate fluorescence YL, which is then emitted. At least a portion of the fluorescence YL emitted from the phosphor layer 251 passes through the second optical layer 2572 of the second optical member 257 covering the light emitting portion 260, and is emitted as illumination light WL.

[0090] Furthermore, a portion of the excitation light EL is reflected by the first optical layer 2542 of the first optical member 254, travels toward the light emitting portion 260, and is reflected by the second optical layer 2572 of the second optical member 257 that covers the light emitting portion 260. The excitation light EL reflected by the second optical layer 2572 passes through at least one of the mirror layer 253, the third optical member 255, and the fourth optical member 256, or passes through none of them, and is then incident directly on the phosphor layer 251, where it is reused for exciting the fluorescence YL.

[0091] In this way, also in the light source device 125 of this embodiment, the excitation light EL emitted from the light source 250 can be efficiently incident on the phosphor layer 251, and the fluorescence YL generated in the phosphor layer 251 can be emitted as the included illumination light WL from the light emitting section 260. Therefore, according to the light source device 125 of this embodiment, bright illumination light WL can be emitted from the light emitting section 260.

[0092] In this embodiment, the light source 250 may be disposed in a recess 261 formed in the substrate 252 .

[0093] (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 first embodiment are denoted by the same reference numerals, and detailed descriptions thereof will be omitted.

[0094] 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 first light source 250A, a second light source 250B, a phosphor layer 251, a substrate 252, a mirror layer 253, a first optical member 254, a second optical member 257, a third optical member 255, a fourth optical member 256, and a light emitting section 260.

[0095] In this embodiment, the first light source 250A and the second light source 250B each have the same configuration as the light source 250 of the first embodiment. That is, the first light source 250A and the second light source 250B emit excitation light EL in the blue wavelength band (first wavelength band) of 400 nm to 480 nm.

[0096] The first light source 250A and the second light source 250B are disposed on a support surface 2521 of a substrate 252. As in the second embodiment, no recesses are formed in the support surface 2521 of the substrate 252. A mirror layer 253 is formed between the first light source 250A and the second light source 250B and the support surface 2521.

[0097] The first light source 250A is arranged on the light emitting section 260 side (+X side) with respect to the phosphor layer 251, and the second light source 250B is arranged on the opposite side (-X side) of the phosphor layer 251 from the light emitting section 260. The first light source 250A, the phosphor layer 251, and the second light source 250B are arranged on the support surface 2521 of the substrate 252 so as to be aligned in the X-axis direction.

[0098] According to the light source device 225 of the present embodiment, the phosphor layer 251 is excited by the excitation light EL emitted from the first light source 250A and the second light source 250B, thereby enabling efficient excitation of the phosphor layer 251. In the case of the present embodiment, the phosphor layer 251 is disposed between the first light source 250A and the second light source 250B, and therefore the excitation light EL emitted from the first light source 250A and the second light source 250B can be incident on the phosphor layer 251 in a balanced manner, thereby generating bright fluorescence YL.

[0099] In this embodiment, the light source 250 may be disposed in a recess 261 formed in the support surface 2521 of the substrate 252 .

[0100] (Fourth embodiment) Next, the configuration of a light source device according to a fourth 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. 8 is a diagram showing the configuration of the light source device of this embodiment. As shown in Figure 8, the light source device 325 of this embodiment includes a light source 250, a first phosphor layer (first wavelength conversion layer) 51, a second phosphor layer (second wavelength conversion layer) 258, a substrate 252, a mirror layer 253, a first optical member 254, a second optical member 257, a third optical member 255, a fourth optical member 256, and a light emitting section 260.

[0102] The first phosphor layer 51 of this embodiment 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 phosphor layer 251 of the first embodiment. The light source 250 is disposed between the first portion 51A and the second portion 51B. The light source 250 is disposed on the support surface 2521 while being sandwiched between the first portion 51A and the second portion 51B. In this embodiment as well, no recess is formed in the support surface 2521 of the substrate 252.

[0103] The second phosphor layer 258 is disposed on the inner surface (surface on the substrate 252 side) 2542a of the first optical layer 2542. In this embodiment, the second phosphor layer 258 is made of the same phosphor material as the first phosphor layer 51. 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 51.

[0104] 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 51. The degree of light scattering can be adjusted by the number of scatterers contained in the phosphor. Pores or transparent particles with a refractive index different from that of the phosphor are used as scatterers. In this embodiment, the number of scatterers contained in the second phosphor layer 258 is smaller than the number of scatterers contained in the first phosphor layer 51. For example, by using a single crystal phosphor, it is possible to achieve a second phosphor layer 258 with fewer scatterers. The second phosphor layer 258 suppresses backscattering of light compared to the first phosphor layer 51, and therefore the excitation light EL incident from the light source 250 can easily travel within the phosphor without being scattered.

[0105] Furthermore, in this embodiment, the thickness of the second phosphor layer 258 is smaller than the thickness of the first phosphor layer 51. The thickness of the second phosphor layer 258 is the dimension in the normal direction of 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 of the first phosphor layer 51 is the dimension in the normal direction of the support surface 2521 on which the first phosphor layer 51 is provided.

[0106] When the thickness of the phosphor is reduced, the excitation light is more likely to exit the phosphor before being converted into fluorescence. 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 51. 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 51.

[0107] It should be noted that, with respect to the first phosphor layer 51, the amount of fluorescence conversion may be controlled by adjusting only one of the amount of scatterers or the thickness of the second phosphor layer 258.

[0108] In the second phosphor layer 258, a portion of the fluorescence YL1 is directly emitted from the second phosphor layer 258, and the remainder of the fluorescence YL1 is reflected by the first optical member 254 and then emitted.

[0109] 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.

[0110] In this embodiment, the first phosphor layer 51 converts a portion of the excitation light EL emitted from the second phosphor layer 258 into fluorescence YL. That is, the first phosphor layer 51 is excited by a portion of the excitation light EL that is emitted from the light source 250 and indirectly enters the first phosphor layer 51 by passing through the second phosphor layer 258.

[0111] In this embodiment, the excitation light EL emitted from the light source 250 is incident on the entire area of ​​the second phosphor layer 258. The second phosphor layer 258 suppresses backscattering and thickness compared to the first phosphor layer 251, thereby suppressing the fluorescence conversion efficiency. Therefore, 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 within the second phosphor layer 258 or reflected by the surface and is emitted toward the support surface 2521 of the substrate 252. In this way, the second phosphor layer 258 emits the excitation light EL toward the support surface 2521 of the substrate 252.

[0112] 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 transmitted through the second optical member 257 and emitted from the light emitting portion 260 as illumination light WL. Alternatively, a portion 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 a portion of the fluorescence YL reflected by the mirror layer 253 passes through the second optical member 257 and is emitted from the light emitting portion 260 as illumination light WL. Furthermore, a portion of the fluorescence YL1 enters the first phosphor layer 51, is backscattered within the first phosphor layer 51 or is reflected by the surface, passes through the second optical member 257, and is emitted as illumination light WL from the light emitting portion 260. Furthermore, a portion of the fluorescence YL1 that entered the first phosphor layer 51 passes through the first phosphor layer 51 and is reflected by the mirror layer 253, passes through the second optical member 257, and is emitted from the light emitting portion 260 as illumination light WL.

[0113] The excitation light EL1 emitted from the second phosphor layer 258 is incident on the first portion 51A and the second portion 51B of the first phosphor layer 51. As described above, the first phosphor layer 51 has a higher degree of light scattering and a greater thickness than the second phosphor layer 258, thereby increasing the fluorescence conversion efficiency. For this reason, most of the excitation light EL1 emitted from the second phosphor layer 258 is converted into fluorescence YL in the first phosphor layer 51 (first portion 51A and second portion 51B). A portion of the fluorescence YL emitted from the first phosphor layer 51 passes through the second optical member 257 and is emitted from the light emitting portion 260 as illumination light WL.

[0114] In addition, a portion of the fluorescence YL emitted from the first phosphor layer 51 enters the second phosphor layer 258, is backscattered by the second phosphor layer 258, passes through the second optical member 257, and is emitted from the light emitting section 260 as illumination light WL. In addition, 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, thereby being emitted from the second phosphor layer 258, and then passes through the second optical member 257 and is emitted from the light emitting section 260 as illumination light WL. 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, transmitted through the second optical member 257, and emitted from the light emitting section 260 as illumination light WL.

[0115] Furthermore, a portion of the excitation light EL and a portion of the fluorescence YL, YL1 enter the third optical member 255 or the fourth optical member 256 via the mirror layer 253, or enter the third optical member 255 or the fourth optical member 256 directly without passing through the mirror layer 253. A portion of the excitation light EL and a portion of the fluorescence YL, YL1 are reflected by the third optical member 255 or the fourth optical member 256, and then pass through the second optical member 257 and are emitted from the light emitting portion 260 as illumination light WL.

[0116] Note that a portion of the excitation light EL 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.

[0117] In this way, in the light source device 325 of this embodiment, illumination light WL containing the fluorescence YL generated in the first phosphor layer 51 and the fluorescence YL1 generated in the second phosphor layer 258 can be emitted from the light emission section 260.

[0118] According to the light source device 325 of the present embodiment, the fluorescence YL1 generated in the second phosphor layer 258 and the fluorescence YL generated in the first phosphor layer 51 can be extracted as illumination light WL from the light emitting section 260. Therefore, according to the light source device 325 of the present embodiment, bright illumination light WL can be emitted from the light emitting section 260.

[0119] Furthermore, in this embodiment, 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 on the support surface 2521 of the substrate 252.

[0120] In this embodiment, the light source 250 may be disposed in a notch formed in the first phosphor layer 51. Furthermore, the light source 250 may be disposed in a recess 261 formed in the support surface 2521 of the substrate 252.

[0121] (First Modification) In the fourth embodiment, the second phosphor layer 258 is made of the same phosphor material as the first phosphor layer 51, but it may be made of a different phosphor material.

[0122] FIG. 9 is a diagram showing the configuration of a light source device according to this modified example. As shown in Figure 9, the light source device 325A of this modified example includes a light source 250, a first phosphor layer 51, a second phosphor layer (second wavelength conversion layer) 1258, a substrate 252, a mirror layer 253, a first optical member 254, a second optical member 257, a third optical member 255, a fourth optical member 256, and a light emitting section 260.

[0123] The second phosphor layer 1258 of this modification converts the excitation light EL into fluorescent light (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 fluorescent light RL emitted by the second phosphor layer 1258 is wider than the yellow wavelength band (second wavelength band) of the fluorescent light YL emitted by the first phosphor layer 51 and the blue wavelength band (first wavelength band) of the excitation light EL emitted by the light source 250. The fluorescent light RL passes through the second optical member 257.

[0124] As such a red phosphor, for example, any one 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. The first phosphor layer 51 may be made of a single phosphor like the phosphor layer 251 in the first and second embodiments.

[0125] In this embodiment, the degree of light scattering in second phosphor layer 1258 is smaller than the degree of light scattering in 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 51.

[0126] Also in this embodiment, by making the thickness of the second phosphor layer 1258 smaller than the thickness of the first phosphor layer 51, the fluorescence conversion efficiency in the second phosphor layer 1258 is suppressed, making it easier to transmit the excitation light EL.

[0127] According to the light source device 325A of this modification, the fluorescence RL generated in the second phosphor layer 1258 and the fluorescence YL generated in the first phosphor layer 51 can be extracted from the light emitting section 260 as illumination light WL1.

[0128] Here, for example, when generating white illumination light of 6500 K, the red component is insufficient using only yellow fluorescence. In contrast, in the light source device 325A of this modification, 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 325A of this modification can generate yellow illumination light WL1 that contains a sufficient amount of red component and has high color reproducibility. Therefore, a projector equipped with the light source device 325A of this embodiment can project an image with high brightness and high reproducibility of red.

[0129] (Second Modification) In the first modification, a phosphor that generates yellow fluorescence is used as the first phosphor layer 51, but a phosphor that generates fluorescence of a different color may also be used.

[0130] FIG. 10 is a diagram showing the configuration of a light source device according to this modified example. As shown in FIG. 10, the light source device 325B of this modified example includes a light source 250, a first phosphor layer 510, a second phosphor layer 1258, a substrate 252, a mirror layer 253, a first optical member 254, a second optical member 257, a third optical member 255, a fourth optical member 256, and a light emitting section 260.

[0131] The first phosphor layer 510 is composed of a first portion 510A and a second portion 510B that are spaced apart from each other. In this modification, the first phosphor layer 510 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 modification, 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 510 and the blue wavelength band (first wavelength band) of the excitation light EL emitted by the light source 250. The fluorescent light GL passes through the second optical member 257.

[0132] The green phosphor constituting the first phosphor layer 510 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+ The first phosphor layer 510 may be composed of two parts like the first phosphor layer 51 of the fourth embodiment, or may be composed of a single phosphor like the phosphor layer 251 of the first and second embodiments.

[0133] In this modification, the degree of light scattering in second phosphor layer 1258 is smaller than the degree of light scattering in first phosphor layer 510. In the case of the present embodiment, the number of scatterers contained in second phosphor layer 1258 is smaller than the number of scatterers contained in first phosphor layer 510.

[0134] Also in this embodiment, by making the thickness of the second phosphor layer 1258 smaller than the thickness of the first phosphor layer 510, the fluorescence conversion efficiency in the second phosphor layer 1258 is suppressed, making it easier to transmit the excitation light EL.

[0135] According to the light source device 325B of this modification, the fluorescence RL generated in the second phosphor layer 1258 and the fluorescence GL generated in the first phosphor layer 510 can be extracted from the light output unit 260 as yellow illumination light WL2.

[0136] The light source device 325B of this modified example uses fluorescence GL, which is green light generated by the first phosphor layer 510, and fluorescence RL, which is red light generated by the second phosphor layer 1258, and is therefore able to generate yellow illumination light WL2 with high color reproducibility in red and green. Therefore, a projector equipped with the light source device 325B of this modified example can project an image with high brightness and high reproducibility of each of the R, G, and B colors.

[0137] 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.

[0138] For example, in the above embodiment, the light emitting portion 260 is formed by the substrate 252, the first optical member 254, the third optical member 255, and the fourth optical member 256, but the light emitting portion may be formed by at least the substrate 252 and the first optical member 254.

[0139] Furthermore, in the above embodiment, an example was given in which the first optical member 254, the third optical member 255, and the fourth optical member 256 are each made up of separate members, but the first optical member 254, the third optical member 255, and the fourth optical member 256 may also be integrally formed from a single member.

[0140] Furthermore, in the first embodiment, an example has been given in which the Z-direction width of the rear surface 2513 of the phosphor layer 251 is narrower than the Z-direction width of the support surface 2521 located in the storage space S. However, the Z-direction width of the rear surface 2513 of the phosphor layer 251 may be the same as the Z-direction width of the support surface 2521 located in the storage space S. In this case, the side surface 2512 of the phosphor layer 251 is in contact with the third optical member 255 and the fourth optical member 256, and therefore the fluorescence YL emitted from the side surface 2512 is reflected by the third optical member 255 and the fourth optical member 256 and returned into the first phosphor layer 51. In other embodiments and modifications, the width of the phosphor layer in the Z direction may be the same as the width of the support surface 2521 in the Z direction.

[0141] 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.

[0142] 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.

[0143] The light source device according to the aspect of the present invention may have the following configuration. The light source device according to one aspect of the present invention includes a substrate having a support surface, and a light source disposed on the support surface side of the substrate. a first light source that emits first light in a first wavelength band; a first optical member having a first optical layer that reflects the first light emitted from the first light source; a light incident surface onto which the emitted first light is incident, the first light being incident on a wavelength band different from the first wavelength band; a first wavelength conversion layer that converts the light into second light in a second wavelength band and emits the second light from the light incident surface; a light emitting portion formed by at least the substrate and the first optical member and emitting light; a second optical layer that reflects the first light and transmits the second light, and is disposed in the light exit portion; and a second optical member formed thereon, wherein the first optical layer is support It is tilted relative to the surface the first wavelength conversion layer reflects the second light, and the first wavelength conversion layer is formed on a surface of the first optical layer facing the substrate; , the support surface of the substrate, and the light emitting portion emits the second light. do.

[0144] In one embodiment of the light source device of the present invention, the first wavelength conversion layer may have a cutout portion cut out and be arranged on the support surface of the substrate, and the first light source may be arranged in the cutout portion of the first wavelength conversion layer.

[0145] In one embodiment of the light source device of the present invention, the light source device may further include a second light source arranged on the support surface side of the substrate and emitting the first light in the first wavelength band, and the first wavelength conversion layer may be arranged on the support surface of the substrate.

[0146] In one aspect of the light source device of the present invention, the first light source may be arranged on the light emitting section side of the first wavelength conversion layer, and the second light source may be arranged on the opposite side of the first wavelength conversion layer from the light emitting section.

[0147] In one embodiment of the light source device of the present invention, the first wavelength conversion layer may be arranged on the support surface of the substrate and include a first portion and a second portion spaced apart from each other, and the first light source may be arranged between the first portion and the second portion.

[0148] In the light source device according to one aspect of the present invention, the first wavelength conversion layer may be disposed on a surface of the first optical layer facing the substrate.

[0149] In one embodiment of the light source device of the present invention, the light source device may further include a second wavelength conversion layer arranged on the other of the substrate-side surface of the first optical layer and the support surface of the substrate, and converting the first light into third light of a third wavelength band different from the first wavelength band, wherein the first wavelength conversion layer is arranged on the support surface of the substrate, and the second wavelength conversion layer is arranged on the substrate-side surface of the first optical layer.

[0150] In the light source device according to one aspect of the present invention, the third wavelength band may be the second wavelength band.

[0151] In one aspect 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 the second light and the third light.

[0152] In the light source device according to one aspect of the present invention, the third wavelength band may be wider than the first wavelength band and the second wavelength band.

[0153] 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 the second light and the third light.

[0154] 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 the second light and the third light.

[0155] In one aspect of the light source device of the present invention, the first light source may be configured to have a light-emitting element, a substrate supporting the light-emitting element, and a reflective layer provided between the substrate and the light-emitting element.

[0156] The optical element may further include a light-transmitting member provided in contact with the light-emitting side of the first light source.

[0157] In the light source device according to one aspect of the present invention, the translucent member may have a third optical layer that is provided on the opposite side to the first light source and transmits the first light and reflects the second light.

[0158] In one aspect of the light source device of the present invention, the substrate may have a recess formed in the support surface, the first light source may be arranged 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.

[0159] The optical element may further include a third optical element having a fourth optical layer that reflects the first light and the second light, and arranged so that the fourth optical layer intersects with the support surface and the first optical layer, and a fourth optical element having a fifth optical layer that reflects the first light and the second light, and arranged so that the fifth optical layer intersects with the support surface and the first optical layer and faces the fourth optical layer, and the light exit portion may be formed by the substrate, the first optical element, the third optical element, and the fourth optical element.

[0160] A projector according to one aspect of the invention may have the following configuration. A projector according to one aspect of the present invention includes the light source device according to the above aspect of the present invention, a light modulation device that modulates light from the light source device, and a projection optical device that projects the light modulated by the light modulation device. [Explanation of symbols]

[0161] 1...Projector, 4B, 4G, 4R...Light modulation device, 6...Projection optical device, 25, 125, 225, 325, 325A, 325B...Light source device, 51...First phosphor layer (first wavelength conversion layer), 51A...First portion, 51B...Second portion, 250...Light source (first light source), 250a...Light emitting element, 250b...Base material, 250c...Reflective layer, 250A...First light source, 250B...Second light source, 251...Phosphor layer (first wavelength conversion layer), 251K...Notch portion, 252...Substrate, 254...First optical portion material, 255...third optical member, 256...fourth optical member, 257...second optical member, 258, 1258...second phosphor layer (second wavelength conversion layer), 259...light-transmitting member, 260...light emitting portion, 261...recess, 2521...support surface, 2511...surface (light incident surface), 2542...first optical layer, 2552...fourth optical layer, 2562...fifth optical layer, 2572...second optical layer, 2592...third optical layer, EL...excitation light (first light), GL, YL, YL1...fluorescence (second light), RL...fluorescence (third light).

Claims

1. a substrate having a support surface; a first light source disposed on the support surface side of the substrate 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 first light source; a first optical member; a light incident surface on which the first light emitted from the first light source is incident, converting the light into second light of a second wavelength band different from the first wavelength band, and emitting the second light from the light incident surface; a first wavelength conversion layer; a light emitting portion formed by at least the substrate and the first optical member and emitting light; 、 a second optical layer that reflects the first light and transmits the second light, the second optical layer being disposed in the light exiting portion; a second optical member; Equipped with the first optical layer is inclined with respect to the support surface and reflects the second light; The first wavelength conversion layer is formed on the surface of the first optical layer facing the substrate and on the support of the substrate. The holding surface is located on one side of the the light emitting unit emits the second light. A light source device characterized by:

2. The first wavelength conversion layer has a notch portion where a part is notched, and the support of the substrate It is placed on the surface, the first light source is disposed in the cutout portion of the first wavelength conversion layer; 2. The light source device according to claim 1.

3. a second light source disposed on the support surface side of the substrate and configured to emit the first light in the first wavelength band; Furthermore, the first wavelength-converting layer is disposed on the support surface of the substrate.

2. The light source device according to claim 1.

4. the first light source is disposed on the light emitting portion side with respect to the first wavelength conversion layer, The second light source is disposed on the opposite side of the first wavelength conversion layer from the light emitting portion. Ru, 4. The light source device according to claim 3.

5. The first wavelength-converting layers are disposed on the support surface of the substrate and spaced apart from one another. a first portion and a second portion, The first light source is disposed between the first portion and the second portion.

2. The light source device according to claim 1.

6. the first wavelength conversion layer is disposed on the surface of the first optical layer facing the substrate; 2. The light source device according to claim 1.

7. and disposed on the other of the surface of the first optical layer facing the substrate and the support surface of the substrate. a second wavelength converter for converting the first light into third light in a third wavelength band different from the first wavelength band; Further provided with a replacement layer, the first wavelength-converting layer is disposed on the support surface of the substrate; the second wavelength conversion layer is disposed on the surface of the first optical layer facing the substrate; 6. The light source device according to claim 1, wherein the light source device is a light source unit.

8. the third wavelength band is the second wavelength band; 8. The light source device according to claim 7.

9. the first light is blue light, and the second light and the third light are yellow light; the light emitting unit emits the second light and the third light.

9. The light source device according to claim 8.

10. the third wavelength band is larger than the first wavelength band and the second wavelength band; 8. The light source device according to claim 7.

11. the first light is blue light, the second light is yellow light, and the third light is red light; the light emitting unit emits the second light and the third light.

11. The light source device according to claim 10.

12. the first light is blue light, the second light is green light, and the third light is red light; the light emitting unit emits the second light and the third light.

11. The light source device according to claim 10.

13. The first light source includes a light emitting element, a substrate supporting the light emitting element, and a light source including the substrate and the light emitting element. a reflective layer provided between the substrate and the light-emitting element; 13. The light source device according to claim 1, wherein the light source device is a light source unit.

14. Further, a light-transmitting member is provided in contact with the light exit side of the first light source.

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

15. The light-transmitting member is provided on the opposite side to the first light source and transmits the first light and the second light. a reflective third optical layer; 15. The light source device according to claim 14.

16. the substrate has a recess formed in the support surface; the first 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, 16. The light source device according to claim 14 or 15.

17. a fourth optical layer that reflects the first light and the second light, a third optical member disposed so as to intersect with the surface and the first optical layer; a fifth optical layer that reflects the first light and the second light, a fourth optical portion disposed so as to intersect the surface and the first optical layer and face the fourth optical layer; and The light exiting portion includes the substrate, the first optical member, the third optical member, and the fourth optical member. formed by the member, 17. The light source device according to claim 1, wherein the light source device is a light source unit.

18. a light source device according to any one of claims 1 to 17; 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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