Light source device and projector

Abstract

The invention provides a light source device and a projector, which are small and generate white illumination light. The light source device includes: a first light source that emits first light; a light separation optical system that separates the first light into a first light beam and a second light beam that are parallel to each other; an optical member through which the first light beam and the second light beam incident from the light separation optical system pass; a condensing optical system that condenses each of the first light beam and the second light beam that have passed through the optical member; and a light scattering element that causes the first light beam and the second light beam emitted from the light collecting optical system to be incident to different positions, respectively, the light scattering element comprising: a substrate having a reflecting surface that reflects light; a first wavelength conversion layer that is disposed on the reflective surface and converts a second light beam incident from the condensing optical system into second light having a wavelength band different from that of the first light; and a light scattering layer that is disposed in a first direction along the reflection surface of the first wavelength conversion layer and scatters a first light beam incident from the light collecting optical system, and an optical member that reflects light emitted from the light scattering element and passing through the light collecting optical system.

Description

Technical Field

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

[0002] As a light source device for a projector, a light source device that generates illumination light using fluorescence generated by a fluorescent layer has been proposed. Patent document 1 below discloses a light source device that includes: a light source unit; a separation and synthesis element that separates light emitted from the light source unit in two orthogonal directions according to polarization components; a diffuser to which one polarization component separated by the separation and synthesis element is incident; and a fluorescent body to which the other polarization component separated by the separation and synthesis element is incident as excitation light. In this light source device, the diffused light of the diffuser and the fluorescence emitted from the fluorescent body are synthesized by the separation and synthesis element to generate illumination light.

[0003] Patent Document 1: Japanese Patent Application Publication No. 2020-79820

[0004] In the above-mentioned light source device, since the diffuser and the phosphor are respectively arranged in two directions orthogonal to the separation and synthesis element, there is a problem that the device structure is enlarged due to the arrangement of optical components in two directions orthogonal to each other. Summary of the invention

[0005] In order to solve the above-mentioned problems, a light source device in one embodiment of the present invention comprises: a first light source that emits a first light; a light separation optical system that separates the first light emitted from the first light source into a first light beam and a second light beam that travel in mutually parallel optical paths; an optical component that allows the first light beam and the second light beam incident from the light separation optical system to pass through; a focusing optical system that focuses the first light beam and the second light beam that have passed through the optical component, respectively; and a light scattering element that focuses the first light beam and the second light beam emitted from the focusing optical system. The light beams are respectively incident on different positions of the light scattering element, and the light scattering element comprises: a substrate having a reflecting surface for reflecting light; a first wavelength conversion layer, which is arranged on the reflecting surface and converts the second light beam incident from the focusing optical system into a second light of a wavelength band different from that of the first light; and a light scattering layer, which is arranged on the first wavelength conversion layer in a first direction along the reflecting surface and scatters the first light beam incident from the focusing optical system, and the optical component reflects the light emitted from the light scattering element and after passing through the focusing optical system.

[0006] In addition, a light source device in another embodiment of the present invention comprises: a first light source that emits a first light composed of coherent light; a second light source that emits a second light composed of incoherent light; an optical component that allows the first light and the second light that are incident in parallel to each other to pass through; a focusing optical system that focuses the first light and the second light that have passed through the optical component, respectively; and a light scattering element, wherein the first light and the second light emitted from the focusing optical system are respectively incident on different positions of the light scattering element, and the light scattering element comprises: a substrate having a reflecting surface for reflecting light; a first wavelength conversion layer that is arranged on the substrate; a reflecting surface for converting the first light incident from the light-converging optical system into a third light of a wavelength band different from the wavelength band of the first light and the wavelength band of the second light; and a light scattering layer, which is arranged on the first wavelength conversion layer in a direction along the reflecting surface and scatters the second light incident from the light-converging optical system, the optical component reflects the light emitted from the light scattering element and passing through the light-converging optical system, and the light scattering degree of the light scattering layer is adjusted so that the angular distribution of the third light emitted from the first wavelength conversion layer is close to the angular distribution of the scattered light of the second light emitted from the light scattering layer.

[0007] A projector according to another embodiment of the present invention comprises: a light source device according to the above embodiment; a light modulator that modulates illumination light emitted from the light source device according to image information; and a projection optical device that projects image light modulated by the light modulator. BRIEF DESCRIPTION OF THE DRAWINGS

[0008] Figure 1 This is a schematic configuration diagram showing a projector according to the first embodiment.

[0009] Figure 2 It is a diagram schematically showing the structure of a light source device.

[0010] Figure 3 This is a diagram showing a light incident surface of a light scattering element as viewed from above.

[0011] Figure 4 This is a schematic configuration diagram showing a light source device according to a second embodiment.

[0012] Figure 5 This is a schematic configuration diagram showing a light source device according to a third embodiment.

[0013] Figure 6 It is a schematic configuration diagram showing a light source device according to a fourth embodiment.

[0014] Figure 7 It is a schematic structural diagram showing a light source device according to a fifth embodiment.

[0015] Figure 8It is a schematic structural diagram showing a light source device according to a sixth embodiment.

[0016] Fig. 9 It is a plan view showing the structure of a light scattering element according to a sixth embodiment.

[0017] Fig.10 It is a schematic structural diagram showing a light source device according to the seventh embodiment.

[0018] Fig.11 It is a schematic structural diagram showing a light source device according to the eighth embodiment.

[0019] Fig.12 1 is a schematic structural diagram showing a light source device according to a modified example.

[0020] Description of symbols

[0021] 1: projector; 2: light source device; 2, 2A, 2B, 2C, 2D, 2E, 2F, 2G, 2H: light source device; 4B, 4G, 4R: light modulation device; 6: projection optical device; 20A, 21: first light source; 20B, 121: second light source; 22, 40, 112, 122: light separation optical system; 22a, 41, 112a: first reflection element; 22b, 42, 112b: second reflection element; 23, 230, 323: optical component; 23A: first area; 23B: second area; 24: focusing optical system; 24a: convex lens; 24AX: optical axis (of focusing optical system); 24C: principal point; 25, 25G, 25H, 50, 60, 125: light scattering element; 25a , 50a, 60a, 125a: light incident surface; 27: beam separation part; 27a: third reflection element; 27b: fourth reflection element; 231, 3231: first optical part; 232, 3232: second optical part; 250, 250C: substrate; 250a: reflection surface; 251, 351, 451, 551: first wavelength conversion layer; 252, 352, 452, 552: light scattering layer; 253, 353: second wavelength conversion layer; D1: first distance; D2: second distance; E1: first light beam; E2: second light beam; E3: third light beam; F: focal length; P1: first position; P2: second position; P3: third position; RL, Y: fluorescence (third light); WL, WL1, WL2: illumination light. DETAILED DESCRIPTION

[0022] In the following, one embodiment of the present invention is described in detail with reference to the accompanying drawings. In addition, in the drawings used in the following description, in order to facilitate understanding of features, sometimes the features are partially enlarged for convenience, and the dimensional ratios of the components are not necessarily the same as the actual ones.

[0023] First Embodiment

[0024] Hereinafter, one embodiment of the present invention will be described.

[0025] Figure 1 This is a schematic configuration diagram showing a projector according to the first embodiment.

[0026] like Figure 1 As shown, the projector 1 of this embodiment is a projection type image display device that displays an image on a screen SCR. The projector 1 includes a light source device 2, a color separation optical system 3, a light modulation device 4R, a light modulation device 4G, a light modulation device 4B, a synthesis optical system 5, and a projection optical device 6.

[0027] The light source device 2 emits white illumination light WL toward the color separation optical system 3. The configuration of the light source device 2 will be described in detail later.

[0028] The color separation optical system 3 separates the illumination light WL emitted from the light source 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, a third reflecting mirror 8c, a first relay lens 9a, and a second relay lens 9b.

[0029] The first dichroic mirror 7a separates the illumination light WL from the light source device 2 into red light LR and light including green light LG and blue light LB. The first dichroic mirror 7a transmits the red light LR and reflects the light including green light LG and blue light LB. On the other hand, the second dichroic mirror 7b reflects the green light LG and transmits the blue light LB. Thus, the second dichroic mirror 7b separates the light including green light LG and blue light LB into green light LG and blue light LB.

[0030] The first reflector 8a is arranged in the optical path of the red light LR, and reflects the red light LR transmitted through the first dichroic mirror 7a toward the light modulator 4R. On the other hand, the second reflector 8b and the third reflector 8c are arranged in the optical path of the blue light LB, and guide the blue light LB transmitted through the second dichroic mirror 7b to the light modulator 4B. The green light LG is reflected from the second dichroic mirror 7b toward the light modulator 4G.

[0031] The first relay lens 9a is disposed between the second dichroic mirror 7b and the second reflector 8b in the optical path of the blue light LB. The second relay lens 9b is disposed between the second reflector 8b and the third reflector 8c in the optical path of the blue light LB. The first relay lens 9a and the second relay lens 9b compensate for the optical loss of the blue light LB caused by the fact that the optical path length of the blue light LB is longer than the optical path lengths of the red light LR and the green light LG.

[0032] The light modulator 4R modulates the red light LR according to the image information to form image light corresponding to the red light LR. The light modulator 4G modulates the green light LG according to the image information to form image light corresponding to the green light LG. The light modulator 4B modulates the blue light LB according to the image information to form image light corresponding to the blue light LB.

[0033] The light modulators 4R, 4G, and 4B each use, for example, a transmissive liquid crystal panel, and polarizing plates (not shown) are disposed on the incident side and the emitting side of the liquid crystal panel.

[0034] A field lens 10R is arranged on the incident side of the light modulator 4R. The field lens 10R collimates the red light LR incident on the light modulator 4R. A field lens 10G is arranged on the incident side of the light modulator 4G. The field lens 10G collimates the green light LG incident on the light modulator 4G. A field lens 10B is arranged on the incident side of the light modulator 4B. The field lens 10B collimates the blue light LB incident on the light modulator 4B.

[0035] The image lights emitted from the light modulators 4R, 4G, and 4B enter the synthesis optical system 5. The synthesis optical system 5 synthesizes the image lights corresponding to the red light LR, the green light LG, and the blue light LB, respectively, and emits the synthesized image lights toward the projection optical device 6. The synthesis optical system 5 uses, for example, a cross dichroic prism.

[0036] The projection optical device 6 includes a plurality of projection lenses. The projection optical device 6 enlarges and projects the image light synthesized by the synthesizing optical system 5 toward the screen SCR. Thus, an enlarged image is displayed on the screen SCR.

[0037] Next, the structure of the light source device 2 will be described.

[0038] Figure 2 1 is a diagram schematically showing the configuration of a light source device 2 according to the present embodiment.

[0039] In the following description, an XYZ orthogonal coordinate system is used as coordinate axes. The axis along the direction in which the illumination light WL is emitted from the light source device 2 is equivalent to the X axis, the axis along the direction in which the light is emitted from the light scattering element described later is equivalent to the Y axis, and the axis along the direction orthogonal to the X axis and the Y axis is equivalent to the Z axis. The illumination light axis 100ax of the light source device 2 is an axis parallel to the X axis.

[0040] like Figure 2 As shown, the light source device 2 includes a first light source 21 , a light separation optical system 22 , an optical component 23 , a light condensing optical system 24 , a light scattering element 25 , and a uniform illumination optical system 30 .

[0041] The first light source 21 is composed of a semiconductor laser 21a that emits blue light composed of laser light. The blue light is, for example, laser light having a blue wavelength band of 440 nm to 490 nm. Thus, the first light source 21 emits blue light E composed of blue light as the first light.

[0042] In addition, as the semiconductor laser 21a, a semiconductor laser emitting blue light of wavelengths other than 445nm, such as 455nm or 460nm, may also be used. In addition, other solid light sources such as LED (Light Emitting Diode) may also be used instead of the semiconductor laser. The optical axis of the first light source 21 is along the X-axis, and the direction in which the first light source 21 emits the blue light E is the -X direction.

[0043] The light separation optical system 22 separates the blue light E emitted from the first light source 21 into a first light beam E1 and a second light beam E2. The light separation optical system 22 includes a first reflecting element 22a and a second reflecting element 22b. The first reflecting element 22a is arranged at an angle of 45 degrees with respect to the optical axis of the blue light E. The second reflecting element 22b is arranged in the -X direction of the first reflecting element 22a in a manner opposite to the first reflecting element 22a.

[0044] The first reflecting element 22a is composed of a half mirror that reflects a part of the blue light E and transmits the rest except the part. The first reflecting element 22a transmits a part of the blue light E incident from the first light source 21 as a first light beam E1 in the -Y direction, and reflects the rest of the blue light E except the part as a second light beam E2 in the -X direction.

[0045] The second light beam E2 reflected by the first reflecting element 22a enters the second reflecting element 22b. The second reflecting element 22b is composed of a reflecting mirror that reflects the second light beam E2. The second reflecting element 22b reflects the second light beam E2 toward the -Y direction.

[0046] In this way, the first light beam E1 and the second light beam E2 separated from the blue light E in the light separation optical system 22 travel along optical paths parallel to each other and enter the optical component 23 .

[0047] In addition, the ratio of the first light beam E1 and the second light beam E2 separated from the blue light E in the light separation optical system 22 can be appropriately changed by adjusting the transmittance of the first reflecting element 22a, etc., according to the white balance of the illumination light WL generated by the light source device 2. In addition, parallel means that the light paths are along each other, and also includes the situation where an angle is formed on the extension line of each other's light paths.

[0048] The optical component 23 allows the first light beam E1 and the second light beam E2 incident from the light separation optical system 22 to pass through. The first light beam E1 and the second light beam E2 that have passed through the optical component 23 are incident on the focusing optical system 24. The focusing optical system 24 focuses the first light beam E1 and the second light beam E2 and guides them to the light scattering element 25. In addition, the focusing optical system 24 makes the light emitted from the light scattering element 25 roughly parallel. The focusing optical system 24 includes a convex lens 24a with positive refractive power. The focusing optical system 24 of this embodiment includes one convex lens 24a, but may also include a plurality of convex lenses.

[0049] The optical component 23 includes a first region 23A for the first light beam E1 to be incident on and a second region 23B for the second light beam E2 to be incident on. The second region 23B is located on the side opposite to the first region 23A with respect to the center 23C of the optical component 23. In the case of the present embodiment, the first region 23A is located in the +X direction with respect to the center 23C of the optical component 23, and the second region 23B is located in the -X direction with respect to the center 23C of the optical component 23. The center 23C of the optical component 23 is consistent with the optical axis 24AX of the focusing optical system 24. That is, the first region 23A and the second region 23B are arranged in a manner that sandwiches the optical axis 24AX of the focusing optical system 24.

[0050] Here, it is assumed that the first region 23A and the second region 23B are arranged on one side of the optical axis 24AX. In this case, the radius of the light-converging optical system 24 needs to have a size that can swallow the first light beam E1 and the second light beam E2 that have passed through the first region 23A and the second region 23B, so there is a problem of enlarging the outer diameter of the light-converging optical system 24. On the other hand, as described above, in the case where the first region 23A and the second region 23B are arranged on both sides of the optical axis 24AX, the light-converging optical system 24 can efficiently take in the first light beam E1 and the second light beam E2, so the enlargement of the outer diameter of the light-converging optical system 24 can be suppressed.

[0051] The first light beam E1 and the second light beam E2 are incident on different areas of the convex lens 24a. The first light beam E1 and the second light beam E2 are incident on areas at different distances from the optical axis 24AX in the radial direction of the convex lens 24a. That is, the distance between the principal ray of the first light beam E1 and the center of the convex lens 24a is different from the distance between the principal ray of the second light beam E2 and the center of the convex lens 24a.

[0052] The first light beam E1 and the second light beam E2 emitted from the condensing optical system 24 enter the light scattering element 25 . Figure 3 FIG. 2 is a diagram showing a light incident surface 25a of the light scattering element 25 when viewed from above. Figure 3 In FIG. 1 , in order to explain the positional relationship between the light scattering element 25 and the light collecting optical system 24 , the light collecting optical system 24 is illustrated by a two-dot chain line.

[0053] like Figure 3 As shown, the light scattering element 25 includes a substrate 250, a first wavelength conversion layer 251, and a light scattering layer 252. The light incident surface 25a of the light scattering element 25 is a surface on the side opposite to the substrate 250 of the first wavelength conversion layer 251 and the light scattering layer 252. The outer shape of the substrate 250 is roughly square. The outer shapes of the first wavelength conversion layer 251 and the light scattering layer 252 are roughly rectangular and have the same size. The light scattering layer 252 is arranged in the first direction along the reflection surface 250a of the first wavelength conversion layer 251, that is, the +X direction. The first wavelength conversion layer 251 and the light scattering layer 252 are generally roughly square in shape.

[0054] Here, the center of the substrate 250 is defined as the center 25C of the light scattering element 25. At this time, the boundary between the first wavelength conversion layer 251 and the light scattering layer 252 is located at the center 25C of the light scattering element 25.

[0055] The substrate 250 is made of a metal plate having excellent heat dissipation properties such as aluminum or copper, and has a reflecting surface 250 a for reflecting light. The reflecting surface 250 a is formed by forming a reflecting film on the surface of the substrate 250 .

[0056] return Figure 2 The first wavelength conversion layer 251 is disposed on the reflection surface 250a of the substrate 250. The first wavelength conversion layer 251 receives the second light beam E2 in the blue wavelength band from the condensing optical system 24 as described later, and converts the second light beam E2 into fluorescent light Y in a different wavelength band.

[0057] The first wavelength conversion layer 251 may include a ceramic phosphor or a single crystal phosphor. The wavelength band of the fluorescence Y has a peak wavelength in the range of 500 nm to 680 nm, for example. That is, the fluorescence Y is yellow light including a green light component and a red light component.

[0058] The first wavelength conversion layer 251 includes, for example, yttrium aluminum garnet (YAG)-based phosphors. Taking YAG:Ce containing cerium (Ce) as an activator as an example, the first wavelength conversion layer 251 can use a material obtained by mixing raw material powders containing constituent elements such as Y2O3, Al2O3, and CeO3 and subjecting them to a solid phase reaction, Y-Al-O amorphous particles obtained by a wet method such as a coprecipitation method and a sol-gel method, YAG particles obtained by a gas phase method such as a spray drying method, a flame pyrolysis method, and a thermal plasma method, etc. In addition, when a porous sintered body is used as the first wavelength conversion layer 251, light is scattered inside the phosphor and it is difficult for the light to propagate laterally, so it is also preferred from the perspective of light utilization efficiency.

[0059] As described later, the light scattering layer 252 receives the first light beam E1 from the focusing optical system 24, and emits blue scattered light E1s after scattering the first light beam E1. The light scattering layer 252 includes a substrate and a plurality of scatterers dispersed in the substrate. The substrate uses a material with high light transmittance, such as inorganic materials such as glass, and organic materials such as resin. The scatterers can preferably use particles with high refractive index such as titanium oxide and zinc oxide.

[0060] A distance D between the principal point 24C of the condensing optical system 24 and the light incident surface 25a of the light scattering element 25 in the Y-axis direction of the optical axis 24AX of the condensing optical system 24 is different from the focal length F of the condensing optical system 24. That is, the condensing optical system 24 is arranged relative to the light scattering element 25 in a defocused state where the first light beam E1 and the second light beam E2 are incident on the light incident surface 25a of the light scattering element 25. The distance D may be greater than the focal length F.

[0061] Here, the farther the light-collecting optical system 24 is from the light-scattering element 25, the larger the outer diameter needs to be in order to take in the light emitted from the light-scattering element 25. In the case of the present embodiment, the distance D is shorter than the focal length F of the light-collecting optical system 24, so the distance between the light-collecting optical system 24 and the light-scattering element 25 can be shortened compared to the case where the distance D is longer than the focal length F. Therefore, in the case of the present embodiment, the outer diameter of the light-collecting optical system 24 can be miniaturized, and the light emitted from the light-scattering element 25 can be efficiently taken in.

[0062] The first light beam E1 and the second light beam E2 in the defocused state are not focused on the light incident surface 25a of the light scattering element 25. Therefore, the illumination spot SP1 formed by the first light beam E1 on the light incident surface 25a and the illumination spot SP2 formed by the second light beam E2 on the light incident surface 25a are arranged at positions separated by different distances from each other in a direction orthogonal to the optical axis 24AX of the focusing optical system 24.

[0063] In this way, Figure 2 As shown, the condensing optical system 24 can condense the first light beam E1 and the second light beam E2 and guide them to different positions on the light incident surface 25a of the light scattering element 25. Therefore, the condensing optical system 24 makes the first light beam E1 incident on the light scattering layer 252 of the light scattering element 25, and makes the second light beam E2 incident on the first wavelength conversion layer 251 of the light scattering element 25.

[0064] Hereinafter, the positional relationship between the light collecting optical system 24 and the light scattering element 25 will be described in more detail.

[0065] like Figure 2 and Figure 3As shown, the condensing optical system 24 and the light scattering element 25 are arranged with the optical axis 24AX offset in the −X direction relative to the center 25C of the light scattering element 25 . That is, the optical axis 24AX of the condensing optical system 24 is located on the first wavelength conversion layer 251 in the light scattering element 25 .

[0066] Here, the distance between the first position P1, which is the incident position of the second light beam E2 in the light scattering element 25, and the second position P2, which is the intersection of the optical axis 24AX of the focusing optical system 24 and the light scattering element 25, in the X-axis direction intersecting the optical axis 24AX is set as the first distance D1. The distance between the third position P3, which is the incident position of the first light beam E1 in the light scattering element 25, and the second position P2 in the X-axis direction is set as the second distance D2. In this embodiment, the first distance D1 is shorter than the second distance D2. That is, the second light beam E2 incident as the excitation light is incident at a position closer to the optical axis 24AX than the first light beam E1.

[0067] The first light beam E1 is incident on the light scattering layer 252 from an oblique direction toward the -X direction and the -Y direction, so the light scattering layer 252 causes the blue scattered light E1s obtained by scattering the first light beam E1 to be emitted in an oblique direction toward the -X direction and the +Y direction relative to the focusing optical system 24. The optical axis 24AX of the focusing optical system 24 of this embodiment is located on the first wavelength conversion layer 251 side (-X side). Therefore, the focusing optical system 24 is arranged at a position offset to the emission side of the blue scattered light E1s, so that the blue scattered light E1s can be efficiently incident on the focusing optical system 24. Therefore, the blue scattered light E1s is roughly parallelized by the focusing optical system 24 and travels along the optical axis 24AX, and is incident on the optical component 23.

[0068] In addition, the first wavelength conversion layer 251 emits the fluorescence Y obtained by wavelength conversion of the second light beam E2 in all directions at a large radiation angle by Lambertian luminescence. The focusing optical system 24 of this embodiment can make the optical axis 24AX located on the first wavelength conversion layer 251, and make the second light beam E2 incident at a position closer to the optical axis 24AX. That is, the luminous center of the fluorescence Y is close to the optical axis 24AX of the focusing optical system 24, so the focusing optical system 24 can efficiently take in the fluorescence Y emitted at a large radiation angle by Lambertian luminescence.

[0069] Therefore, the fluorescence Y is substantially parallelized by the focusing optical system 24 , travels along the optical axis 24AX, and enters the optical component 23 .

[0070] The optical component 23 of this embodiment includes a first optical portion 231 and a second optical portion 232. The first optical portion 231 is composed of a dichroic mirror composed of a dielectric multilayer film that transmits the first light beam E1 and the second light beam E2 and reflects the fluorescence Y. The first optical portion 231 is arranged at an angle of 45 degrees with respect to the optical axis 24AX of the focusing optical system 24.

[0071] The fluorescence Y collimated by the focusing optical system 24 is reflected toward the +X direction by the first optical part 231 and enters the uniform illumination optical system 30. In addition, the blue scattered light E1s collimated by the focusing optical system 24 is light of the same blue wavelength as the first light beam E1, so the first optical part 231 allows the blue scattered light E1s to pass through. The blue scattered light E1s that has passed through the first optical part 231 enters the second optical part 232 arranged in the +Y direction of the first optical part 231. The second optical part 232 is arranged at an angle of 45 degrees with respect to the optical axis 24AX of the focusing optical system 24.

[0072] The second optical portion 232 reflects the blue scattered light E1s in the +X direction. The blue scattered light E1s reflected in the +X direction by the second optical portion 232 passes through the first optical portion 231 and enters the uniform illumination optical system 30. That is, the second optical portion 232 generates white illumination light WL by guiding the blue scattered light E1s in the same direction as the fluorescence Y reflected by the first optical portion 231, that is, the optical path of the fluorescence Y. According to this configuration, by making the optical paths of the blue scattered light E1s and the fluorescence Y consistent, color unevenness of the illumination light WL can be suppressed.

[0073] The second optical portion 232 is disposed at a position that does not overlap with the optical paths of the first light beam E1 and the second light beam E2 . Therefore, the second optical portion 232 does not block the first light beam E1 and the second light beam E2 heading toward the light scattering element 25 .

[0074] Thus, the optical component 23 reflects the light emitted from the light scattering element 25, that is, the blue scattered light E1s and the fluorescence Y, and makes them enter the uniform illumination optical system 30 as the illumination light WL. The optical component 23 and the uniform illumination optical system 30 are arranged along the illumination optical axis 100ax of the light source device 2. The uniform illumination optical system 30 includes a first lens array 31, a second lens array 32, a polarization conversion element 33, and a superimposing lens 34.

[0075] The first lens array 31 includes a plurality of first lenses 31a for splitting the illumination light WL incident from the optical component 23 into a plurality of partial light beams. The plurality of first lenses 31a are arranged in a matrix in a plane orthogonal to the illumination optical axis 100ax.

[0076] The second lens array 32 includes a plurality of second lenses 32b corresponding to the plurality of first lenses 31a of the first lens array 31. The plurality of second lenses 32b are arranged in a matrix in a plane orthogonal to the illumination optical axis 100ax.

[0077] The second lens array 32 forms images of the first lenses 31 a of the first lens array 31 in the vicinity of the image forming regions of the light modulators 4R, 4G, and 4B together with the superimposing lens 34 .

[0078] The polarization conversion element 33 converts the light emitted from the second lens array 32 into one linearly polarized light. The polarization conversion element 33 includes, for example, a polarization separation film and a phase difference plate (not shown).

[0079] The superimposing lens 34 converges the partial light beams emitted from the polarization conversion element 33 and superimposes them near the image forming regions of the light modulators 4R, 4G, and 4B. The uniform illumination optical system 30 may include a rod lens for uniformizing the illumination distribution of light.

[0080] As described above, the light source device 2 of the present embodiment comprises: a first light source 21 that emits blue light E; a light separation optical system 22 that separates the blue light E emitted from the first light source 21 into a first light beam E1 and a second light beam E2 that travel in mutually parallel optical paths; an optical component 23 that allows the first light beam E1 and the second light beam E2 that are incident from the light separation optical system 22 to pass through; a focusing optical system 24 that focuses the first light beam E1 and the second light beam E2 that have passed through the optical component 23 and guides them to different positions; and a light scattering element 25, onto which the first light beam E1 and the second light beam E2 emitted from the focusing optical system 24 are incident. The light scattering element 25 includes: a substrate 250 having a reflecting surface 250a for reflecting light; a first wavelength conversion layer 251 disposed on the reflecting surface 250a for converting the second light beam E2 incident from the light-collecting optical system 24 into fluorescent light Y in a yellow wavelength band different from a blue wavelength band; and a light scattering layer 252 disposed in the X-axis direction along the reflecting surface 250a of the first wavelength conversion layer 251 for scattering the first light beam E1 incident from the light-collecting optical system 24. The optical component 23 reflects the light emitted from the light scattering element 25 and passing through the light-collecting optical system 24.

[0081] According to the light source device 2 of this embodiment, light emitted from the light scattering element 25, which is arranged in the -Y direction of the optical component 23 and has the light scattering layer 252 and the first wavelength conversion layer 251, can be taken out as illumination light WL by using the condensing optical system 24 and the optical component 23. Therefore, the light emitted from the light scattering layer 252 and the first wavelength conversion layer 251 can be parallelized and guided to the optical component 23 by the common condensing optical system 24. On the other hand, in the case where the light scattering layer and the first wavelength conversion layer are separately arranged in two directions of the optical component 23, the device structure becomes large-scale because the condensing optical systems are arranged for the light scattering layer and the first wavelength conversion layer respectively.

[0082] According to the light source device 2 of the present embodiment, it is possible to generate white illumination light WL while suppressing an increase in the size of the device structure.

[0083] The projector 1 of the present embodiment includes the light source device 2 described above, and therefore, can realize a small-sized projector that displays color images.

[0084] Second Embodiment

[0085] Hereinafter, a light source device according to a second embodiment will be described.

[0086] The basic structure of the second embodiment is the same as that of the first embodiment, but the structure of the light separation optical system is different from that of the first embodiment. Therefore, the structure of the light separation optical system is mainly described below, and the same reference numerals are given to the same structural elements as those in the drawings used in the above embodiments, and the description thereof is omitted.

[0087] Figure 4 It is a schematic configuration diagram showing a light source device 2A according to the second embodiment.

[0088] like Figure 4 As shown, the light source device 2A of the present embodiment includes a first light source 21 , a light separation optical system 112 , an optical component 23 , a light collecting optical system 24 , a light scattering element 25 , and a uniform illumination optical system 30 .

[0089] The light separation optical system 112 of this embodiment separates the blue light E emitted from the first light source 21 into the first light beam E1 and the second light beam E2. The light separation optical system 112 has a first reflecting element 112a and a second reflecting element 112b. The first reflecting element 112a is configured to form an angle of 45 degrees with respect to the optical axis of the blue light E. The second reflecting element 112b is configured to form an angle of 45 degrees with respect to the optical axis of the blue light E, and is configured in the -X direction of the first reflecting element 112a.

[0090] The first reflecting element 112a is composed of a half mirror that reflects a part of the blue light E and transmits the rest except the part. The first reflecting element 112a reflects a part of the blue light E incident from the first light source 21 as a first light beam E1 in the -Y direction, and transmits the rest of the blue light E except the part as a second light beam E2 in the -X direction.

[0091] The second light beam E2 transmitted through the first reflecting element 112a enters the second reflecting element 112b. The second reflecting element 112b is composed of a reflecting mirror that reflects the second light beam E2. The second reflecting element 112b reflects the second light beam E2 toward the -Y direction.

[0092] In this way, the first light beam E1 and the second light beam E2 separated from the blue light E in the light separation optical system 112 travel along optical paths parallel to each other and enter the optical component 23 .

[0093] The ratio of the first light beam E1 and the second light beam E2 separated from the blue light E in the light separation optical system 112 can be appropriately changed by adjusting the transmittance of the first reflection element 112 a or the like according to the white balance of the illumination light WL generated by the light source device 2A.

[0094] In the light source device 2A of the present embodiment, similarly to the light source device 2 of the first embodiment, it is possible to generate white illumination light WL while suppressing an increase in the size of the device structure.

[0095] Third Embodiment

[0096] Hereinafter, a light source device according to a third embodiment will be described.

[0097] The basic structure of the third embodiment is the same as that of the first embodiment, but the structure of the optical component is different from that of the first embodiment. Therefore, the structure of the optical component will be mainly described below, and the same components as those in the drawings used in the above embodiments are denoted by the same reference numerals and their description will be omitted.

[0098] Figure 5 It is a schematic configuration diagram showing a light source device 2B according to the third embodiment.

[0099] like Figure 5 As shown, the light source device 2B of the present embodiment includes a first light source 21 , a light separation optical system 22 , an optical component 230 , a light condensing optical system 24 , a light scattering element 25 , and a uniform illumination optical system 30 .

[0100] The optical component 230 of this embodiment includes a third optical portion 233 and a reflective mirror 234 fitted into an opening 233a provided in the third optical portion 233. The third optical portion 233 is composed of a dielectric multilayer film that transmits the first light beam E1 and the second light beam E2 and reflects the fluorescence Y.

[0101] The reflecting mirror 234 is disposed at a position not overlapping with the optical paths of the first light beam E1 and the second light beam E2 , and thus does not block the first light beam E1 and the second light beam E2 heading toward the light scattering element 25 .

[0102] In the optical component 230 of the present embodiment, the reflector 234 reflects the light incident from the light scattering element 25. That is, the reflector 234 reflects the fluorescence Y and the blue scattered light E1s in the +X direction and causes them to enter the uniform illumination optical system 30 as illumination light WL.

[0103] According to this configuration, the third optical portion 233 can be used as a holding member for the reflecting mirror 234. Therefore, the number of components constituting the optical member 230 can be kept small.

[0104] In the light source device 2B of the present embodiment, similarly to the light source device 2A of the first embodiment, it is possible to generate white illumination light WL while suppressing an increase in the size of the device structure.

[0105] Fourth Embodiment

[0106] Hereinafter, a light source device according to a fourth embodiment will be described.

[0107] In the structure of the fourth embodiment, the second light source is also provided, which is different from the structure of the second embodiment, but the other structures are the same. Therefore, the structure of the second light source is mainly described below, and the same reference numerals are used for the same structural elements as those in the drawings used in the above-mentioned embodiments, and the description is omitted.

[0108] Figure 6 It is a schematic configuration diagram showing a light source device 2C according to the fourth embodiment.

[0109] like Figure 6 As shown, the light source device 2C of this embodiment includes a first light source 21 , a second light source 121 , a light separation optical system 40 , a combining mirror 43 , an optical component 323 , a condensing optical system 24 , a light scattering element 25 , and a uniform illumination optical system 30 .

[0110] The second light source 121 is composed of a semiconductor laser 121a that emits a red light composed of laser. The red light is, for example, a laser with a red wavelength band of 610nm to 750nm. The second light source 121 emits a red light R composed of red light as the second light. Usually, the output of a red laser is weaker than that of a blue laser. Therefore, it is preferred that the number of semiconductor lasers 121a of the second light source 121 is greater than the number of semiconductor lasers 21a of the first light source 21. In addition, in the case where the beam width of the red light R is expanded by increasing the number of semiconductor lasers 121a, the beam width of the red light R can also be reduced using an afocal optical system to make it consistent with the beam width of the blue light E, thereby suppressing the occurrence of color unevenness.

[0111] The combining mirror 43 is disposed at an angle of 45 degrees with respect to the optical axis of the second light source 121. The combining mirror 43 reflects the red light R incident from the second light source 121 in the −X direction and causes the red light R to enter the light separation optical system 40.

[0112] The light separation optical system 40 includes a first reflecting element 41 and a second reflecting element 42. The first reflecting element 41 is arranged at an angle of 45 degrees with respect to the optical axis of the blue light E. The second reflecting element 42 is arranged at an angle of 45 degrees with respect to the optical axis of the blue light E and is arranged in the -X direction of the first reflecting element 41.

[0113] The first reflecting element 41 is composed of a stacked half mirror 41a and a dichroic mirror 41b. The half mirror 41a is arranged to face the first light source 21, and the dichroic mirror 41b is arranged to face the synthesizing mirror 43. The half mirror 41a reflects a part of the blue light E and transmits the rest except for a part. The dichroic mirror 41b has the characteristic of reflecting the red light R incident from the synthesizing mirror 43 and transmitting the other light.

[0114] The half mirror 41a of the first reflecting element 41 allows a portion of the blue light E incident from the first light source 21 to pass through as the first light beam E1 in the -Y direction, and the first light beam E1 passes through the dichroic mirror 41b. The half mirror 41a of the first reflecting element 41 reflects the remaining portion of the blue light E except for a portion as the second light beam E2 in the -X direction. The first reflecting element 41 guides the red light R to the optical path of the first light beam E1. In addition, the second light beam E2 is emitted from the first reflecting element 41 without being incident on the dichroic mirror 41b.

[0115] On the other hand, the red light R reflected by the combining mirror 43 is reflected in the -Y direction by the dichroic mirror 41 b of the first reflecting element 41 and does not enter the half mirror 41 a side.

[0116] In this way, the first reflecting element 41 reflects the second light beam E2 which is a part of the blue light E and the red light R, and transmits the first light beam E1 which is the remaining part of the blue light E except for a part of it.

[0117] The second reflecting element 42 is constituted by a reflecting mirror that reflects the second light beam E2. The second reflecting element 42 reflects the second light beam E2 toward the -Y direction.

[0118] In this way, the first light beam E1 and the second light beam E2 , and the red light R separated from the blue light E in the light separation optical system 40 travel along mutually parallel optical paths and enter the optical component 323 .

[0119] The optical component 323 includes a first optical portion 3231 and a second optical portion 3232. The first optical portion 3231 is composed of a dichroic mirror composed of a dielectric multilayer film that transmits blue light E and reflects fluorescence Y. In the present embodiment, the first optical portion 3231 is not disposed on the optical paths of the first light beam E1 and the red light R.

[0120] The first optical portion 3231 has a characteristic of reflecting the fluorescence Y. The red wavelength band is included in the fluorescence Y which is yellow light, and therefore, the first optical portion 3231 reflects the red light R. In contrast, in the optical component 323 of the present embodiment, by not arranging the first optical portion 3231 on the optical path of the red light R, the red light R can be transmitted in the -Y direction. In addition, the first optical portion 3231 may also form an opening at the position where the first light beam E1 and the red light R are incident, so that the first light beam E1 and the red light R pass in the -Y direction.

[0121] The red light R is condensed in a defocused state by the condensing optical system 24 and enters the light scattering layer 252 of the light scattering element 25 together with the first light beam E1. The light scattering layer 252 emits the red scattered light Rs obtained by scattering the red light R and the blue scattered light E1s obtained by scattering the first light beam E1 toward the condensing optical system 24.

[0122] The blue scattered light E1s collimated by the condensing optical system 24 passes through the first optical portion 3231, is reflected in the +X direction by the second optical portion 3232, passes through the first optical portion 3231 again, and enters the uniform illumination optical system 30. On the other hand, the red scattered light Rs collimated by the condensing optical system 24 is reflected in the +X direction by the first optical portion 3231 and enters the uniform illumination optical system 30.

[0123] In this way, the optical component 323 of the present embodiment reflects the blue scattered light E1s, the red scattered light Rs, and the fluorescence Y emitted from the light scattering element 25 , and makes them incident on the uniform illumination optical system 30 as the illumination light WL1 .

[0124] The white light using the fluorescent light Y generated by the first wavelength conversion layer 251 composed of yellow fluorescent material sometimes has a color tone with insufficient red components. In contrast, according to the light source device 2C of this embodiment, by adding red scattered light Rs after scattering the red light R emitted from the second light source 121, white illumination light WL1 containing sufficient red components can be obtained.

[0125] Fifth Embodiment

[0126] Hereinafter, a light source device according to a fifth embodiment will be described.

[0127] The basic structure of the fifth embodiment is the same as that of the first embodiment, but the structure of the light scattering element is different from that of the first embodiment. Therefore, the structure of the light scattering element will be mainly described below, and the same components as those in the drawings used in the above embodiments are denoted by the same reference numerals and their description will be omitted.

[0128] Figure 7 It is a schematic configuration diagram showing a light source device 2D according to the fifth embodiment.

[0129] like Figure 7 As shown, the light source device 2D of the present embodiment includes a first light source 21 , a light separation optical system 112 , an optical component 23 , a light condensing optical system 24 , a light scattering element 125 , and a uniform illumination optical system 30 .

[0130] The light scattering element 125 of this embodiment includes a substrate 250, a first wavelength conversion layer 251, a light scattering layer 252, and a second wavelength conversion layer 253. The light incident surface 125a of the light scattering element 125 is a surface on the opposite side of the substrate 250 among the first wavelength conversion layer 251, the second wavelength conversion layer 253, and the light scattering layer 252. The first wavelength conversion layer 251 and the second wavelength conversion layer 253 have a substantially rectangular shape and have the same size. The light scattering layer 252 has a substantially rectangular shape and has the same size as the sum of the first wavelength conversion layer 251 and the second wavelength conversion layer 253.

[0131] Here, the center of the substrate 250C is defined as the center 125C of the light scattering element 125 . At this time, the boundary between the first wavelength conversion layer 251 and the light scattering layer 252 is located at the center 125C of the light scattering element 125 .

[0132] The second wavelength conversion layer 253 is disposed on the side of the first wavelength conversion layer 251 opposite to the light scattering layer 252 (-X direction). As described later, the second wavelength conversion layer 253 receives the second light beam E2 in the blue wavelength band from the focusing optical system 24, and converts the second light beam E2 into fluorescence RL in a wavelength band different from the fluorescence Y. The wavelength band of the fluorescence RL of the second wavelength conversion layer 253 has a peak wavelength in the range of 600 nm to 800 nm, for example. That is, the fluorescence RL is red light containing a red light component.

[0133] The second wavelength conversion layer 253 is made of, for example, (Y 1-x , Gd x )3(Al,Ga)5O 12 The YAG-based phosphor (any one of Pr:YAG, Eu:YAG, and Cr:YAG) may be composed of the activator. In addition, the activator may include one selected from Pr, Eu, and Cr, or may be a co-activated activator including a plurality of selected from Pr, Eu, and Cr.

[0134] The condensing optical system 24 of this embodiment condenses the first light beam E1 and the second light beam E2 and guides them to different positions on the light incident surface 125a of the light scattering element 125. Specifically, the condensing optical system 24 causes the first light beam E1 and the second light beam E2 to be incident on the light scattering element 125 in such a manner that the first light beam E1 is incident on the light scattering layer 252 and the second light beam E2 crosses the boundary between the first wavelength conversion layer 251 and the second wavelength conversion layer 253. That is, the second light beam E2 is not branched into two light beams, and the second light beam E2 can excite the first wavelength conversion layer 251 and the second wavelength conversion layer 253. Therefore, there is no need to change the structure of the light separation optical system 112.

[0135] In the case of this embodiment, the first wavelength conversion layer 251 emits the fluorescence Y obtained by wavelength conversion of the second light beam E2 in all directions at a large radiation angle through Lambertian luminescence, and the second wavelength conversion layer 253 emits the fluorescence RL obtained by wavelength conversion of the second light beam E2 in all directions at a large radiation angle through Lambertian luminescence.

[0136] like Figure 7As shown in FIG. 1 , the light-collecting optical system 24 and the light-scattering element 125 are mutually arranged in such a manner that the optical axis 24AX is offset in the −X direction relative to the center 125C of the light-scattering element 125. That is, the optical axis 24AX of the light-collecting optical system 24 is located at a position closer to the first wavelength conversion layer 251 than the center 125C of the light-scattering element 125. Therefore, the emission center of the fluorescent light Y and RL is close to the optical axis 24AX of the light-collecting optical system 24, so the light-collecting optical system 24 can efficiently take in the fluorescent light Y and RL emitted at a large radiation angle by Lambertian luminescence. The fluorescent light Y and RL are roughly parallelized by the light-collecting optical system 24 and travel along the optical axis 24AX, and are incident on the optical component 23.

[0137] Here, a part of the wavelength band of the fluorescence RL overlaps with the fluorescence Y in the yellow wavelength band. Therefore, the first optical part 231 of the optical component 23 in this embodiment has the characteristic of reflecting the fluorescence RL in the red wavelength band. As a result, the fluorescence Y and RL collimated by the focusing optical system 24 are reflected in the +X direction by the first optical part 231 and enter the uniform illumination optical system 30. In addition, the blue scattered light E1s collimated by the focusing optical system 24 passes through the first optical part 231 and is reflected in the +X direction by the second optical part 232, and passes through the first optical part 231 again and enters the uniform illumination optical system 30.

[0138] In the light source device 2D of the present embodiment, the optical member 23 reflects the blue scattered light E1s, the fluorescent light RL, and the fluorescent light Y emitted from the light scattering element 125 , and makes them incident on the uniform illumination optical system 30 as the illumination light WL2 .

[0139] According to the light source device 2D of the present embodiment, by adding the red fluorescent light RL emitted from the second wavelength conversion layer 253 , it is possible to obtain white illumination light WL2 containing a sufficient red component.

[0140] Sixth Embodiment

[0141] Hereinafter, a light source device according to a sixth embodiment will be described.

[0142] The structure of the sixth embodiment is the same as that of the first embodiment, but the structures of the light scattering element and the light separation optical system are different from those of the first embodiment. Therefore, the structures of the light scattering element and the light separation optical system are mainly described below, and the same reference numerals are given to the same structural elements as those in the drawings used in the above embodiments, and the description thereof is omitted.

[0143] Figure 8 It is a schematic configuration diagram showing a light source device 2E according to the sixth embodiment.

[0144] like Figure 8As shown, the light source device 2E of the present embodiment includes a first light source 21 , a light separation optical system 122 , an optical component 23 , a light collecting optical system 24 , a light scattering element 50 , and a uniform illumination optical system 30 .

[0145] Fig. 9 FIG. 4 is a top view showing the structure of the light scattering element 50 of this embodiment. Fig. 9 As shown in FIG. 1 , the light scattering element 50 of the present embodiment includes a substrate 250, a first wavelength conversion layer 351, a light scattering layer 352, and a second wavelength conversion layer 353. The light incident surface 50a of the light scattering element 50 is a surface of the first wavelength conversion layer 351, the second wavelength conversion layer 353, and the light scattering layer 352 that is opposite to the substrate 250. That is, the light scattering element 50 of the present embodiment is different from the light scattering element 125 of the fifth embodiment in the layout of each wavelength conversion layer and the light scattering layer.

[0146] The first wavelength conversion layer 351 and the light scattering layer 352 have substantially square outer shapes and are of equal size. The first wavelength conversion layer 351 and the light scattering layer 352 are arranged along the X direction on the substrate 250 .

[0147] The second wavelength conversion layer 353 is arranged in the second direction, that is, the -Z direction, which intersects the first direction (+X direction) along the reflection surface 250a of the first wavelength conversion layer 251. The second wavelength conversion layer 353 has a substantially rectangular shape and has a size equal to the total size of the first wavelength conversion layer 351 and the light scattering layer 352. That is, the first wavelength conversion layer 351, the light scattering layer 352, and the second wavelength conversion layer 353 have a substantially square shape as a whole.

[0148] The light separation optical system 122 of this embodiment includes a first reflecting element 22a, a second reflecting element 22b, and a beam separation unit 27. In the light separation optical system 122, the component of the blue light E transmitted by the first reflecting element 22a in the -Y direction is incident on the optical component 23 as the first beam E1. In addition, the component of the blue light E reflected by the first reflecting element 22a in the -X direction is incident on the beam separation unit 27. The beam separation unit 27 separates a part of the blue light E into a third beam E3 that travels in an optical path parallel to the first beam E1 and the second beam E2.

[0149] The beam splitting unit 27 includes a third reflecting element 27 a and a fourth reflecting element 27 b .

[0150] The third reflecting element 27a is arranged to form an angle of 45 degrees with the X-axis and the Z-axis in the XZ plane. The third reflecting element 27a is composed of a half mirror, and reflects a part of the blue light E reflected by the first reflecting element 22a as the third light beam E3 in the second direction, i.e., the -Z direction, and transmits another part of the blue light E as the second light beam E2 in the -X direction.

[0151] The fourth reflecting element 27b is constituted by a reflecting mirror that reflects the third light beam E3 incident from the third reflecting element 27a toward the optical member 23. The fourth reflecting element 27b is disposed at an angle of 45 degrees with the Y axis and the Z axis in the YZ plane, and reflects the third light beam E3 in the -Y direction.

[0152] In this way, the first light beam E1 , the second light beam E2 , and the third light beam E3 separated from the blue light E in the light separation optical system 122 travel along mutually parallel optical paths and enter the optical component 23 .

[0153] The focusing optical system 24 focuses the first light beam E1, the second light beam E2, and the third light beam E3 and guides them to different positions on the light incident surface 50a of the light scattering element 50. Fig. 9 As shown, the condensing optical system 24 causes the first light beam E1 to be incident on the light scattering layer 352 of the light scattering element 50, causes the second light beam E2 to be incident on the first wavelength conversion layer 351 of the light scattering element 50, and causes the third light beam E3 to be incident on the second wavelength conversion layer 353 of the light scattering element 50. That is, the condensing optical system 24 of this embodiment causes the third light beam E3 reflected by the fourth reflecting element 27b and transmitted through the optical component 23 to be incident on the second wavelength conversion layer 353.

[0154] The behaviors of the fluorescent light Y and RL and the blue scattered light E1s generated by the light scattering element 50 are the same as those of the light scattering element 125 according to the fifth embodiment, and thus description thereof will be omitted.

[0155] According to the light source device 2E of the present embodiment, by adding the red fluorescent light RL emitted from the second wavelength conversion layer 353 , it is possible to obtain white illumination light WL2 containing a sufficient red component.

[0156] Seventh Embodiment

[0157] Hereinafter, a light source device according to a seventh embodiment will be described.

[0158] The basic structure of the seventh embodiment is the same as that of the first embodiment, but the structures of the light source unit and the light scattering element are different from those of the first embodiment. Therefore, the structure of the light source unit and the light scattering element will be mainly described below, and the same reference numerals are given to the same components as those in the drawings used in the above embodiments, and the description thereof will be omitted.

[0159] Fig.10It is a schematic configuration diagram showing a light source device 2F according to the seventh embodiment.

[0160] like Fig.10 As shown, the light source device 2F of the present embodiment includes a first light source 20A, a second light source 20B, an optical member 23 , a condensing optical system 24 , a light scattering element 60 , and a uniform illumination optical system 30 .

[0161] The first light source 20A of the present embodiment is constituted by a semiconductor laser 20a that emits laser light having a blue wavelength band of 440 to 490 nm, for example. Therefore, the first light source 20A emits blue light B1 as first light consisting of coherent light.

[0162] On the other hand, the second light source 20B of the present embodiment is composed of an LED element 20b that emits light in the same blue wavelength band as the first light source 20A. That is, the second light source 20B emits blue light B2 as second light composed of incoherent light.

[0163] The first light source 20A and the second light source 20B are arranged so that their optical axes are along the Y direction. That is, the blue light B1 and B2 emitted from the first light source 20A and the second light source 20B are incident on the optical component 23 in parallel with each other. The optical component 23 allows the blue light B1 and B2 to pass through. In addition, parallelism only requires that the optical path of the first light and the optical path of the second light are along, including the case where an angle is formed on the extension line of each other's optical paths.

[0164] The focusing optical system 24 focuses the blue light B1 and B2 transmitted through the optical component 23 and guides them to different positions of the light scattering element 60. The blue light B1 and B2 are incident on different areas of the convex lens 24a constituting the focusing optical system 24. The blue light B1 and B2 are incident on areas at different distances from the optical axis 24AX in the radial direction of the convex lens 24a.

[0165] The light scattering element 60 includes a substrate 250, a first wavelength conversion layer 451, and a light scattering layer 452. The light incident surface 60a of the light scattering element 60 is a surface of the first wavelength conversion layer 451 and the light scattering layer 452 on the opposite side from the substrate 250. The light scattering layer 452 is arranged in the first direction along the reflection surface 250a of the first wavelength conversion layer 451, that is, in the +X direction.

[0166] The light-converging optical system 24 causes the blue light B2 to be incident on the light-scattering layer 452 of the light-scattering element 60, and causes the blue light B1 to be incident on the first wavelength conversion layer 451 of the light-scattering element 60. The light-scattering layer 452 emits the blue scattered light B2s obtained by scattering the blue light B2 toward the light-converging optical system 24, and the first wavelength conversion layer 451 emits the fluorescent light Y toward the light-converging optical system 24.

[0167] The first wavelength conversion layer 451 emits fluorescence Y, which is a third light of a wavelength band different from the wavelength bands of the blue light B1 and the blue light B2, in all directions at a large radiation angle by Lambertian luminescence. That is, the fluorescence Y has a large angular distribution. The inventors of the present invention have focused on the fact that when a fluorescent body is excited to generate fluorescence, when coherent light and incoherent light are used as excitation light, the angular distribution of the generated fluorescence differs.

[0168] In the light source device 2F of the present embodiment, blue light B1 composed of laser light as coherent light is made incident as excitation light to the first wavelength conversion layer 451. Here, when blue light B2 as incoherent light is made incident as excitation light to the first wavelength conversion layer 451, the degree of scattering of the fluorescence Y becomes greater than when the blue light B1 is made as excitation light. That is, when the blue light B2 is made incident on the first wavelength conversion layer 451, the angular distribution of the fluorescence Y is further expanded, and the fluorescence Y cannot be efficiently taken in by the focusing optical system 24, and the light utilization efficiency may be reduced.

[0169] In contrast, in the light source device 2F of the present embodiment, as described above, the angular distribution of the fluorescence Y is suppressed to be smaller by causing the blue light B1 composed of laser light to be incident on the first wavelength conversion layer 451 as excitation light. Thus, the spread of the angular distribution of the fluorescence Y can be suppressed, and therefore, the focusing optical system 24 can efficiently use the fluorescence Y as the illumination light WL by efficiently taking in the fluorescence Y.

[0170] In the light source device 2F of this embodiment, the light scattering degree of the light scattering layer 452 is adjusted so that the angular distribution of the fluorescence Y emitted from the first wavelength conversion layer 451 is close to the angular distribution of the blue scattered light B2s of the blue light B2 emitted from the light scattering layer 452 .

[0171] In order to make the angular distribution of the blue scattered light B2s close to the fluorescent light Y having a large angular distribution, it is necessary to increase the degree of scattering by the light scattering layer 452 .

[0172] The inventors of the present invention have focused on the fact that incoherent light is more easily scattered when coherent light is compared with incoherent light. In addition, in the light source device 2F of the present embodiment, the angular distribution of the fluorescence Y is suppressed by using the blue light B1 composed of laser light as the excitation light, and the blue light B2 of incoherent light that is more easily scattered than the laser light is made incident on the light scattering layer 452. Therefore, according to the light source device 2F of the present embodiment, the scattering degree of the light scattering layer 452 can be suppressed to a smaller extent, so that the manufacturing cost of the light scattering layer 452 can be suppressed.

[0173] The optical member 23 reflects the fluorescence Y and the blue scattered light E1 s emitted from the light scattering element 60 in the +X direction and causes the light to enter the uniform illumination optical system 30 , similarly to the above-described embodiment.

[0174] According to the light source device 2F of this embodiment, by allowing appropriate blue lights B1 and B2 to enter the light scattering layer 452 and the first wavelength conversion layer 451 of the light scattering element 60 , it is possible to suppress the spread of the angular distribution of the fluorescence Y and reduce the cost of the light scattering element 60 .

[0175] Eighth Embodiment

[0176] Hereinafter, a light source device according to an eighth embodiment will be described.

[0177] The basic structure of the eighth embodiment is the same as that of the first embodiment, but the structure of the light scattering element is different from that of the first embodiment. Therefore, the structure of the light scattering element is mainly described below, and the same components as those in the drawings used in the above embodiments are marked with the same reference numerals and the description thereof is omitted.

[0178] Fig.11 It is a schematic configuration diagram showing a light source device 2G according to the eighth embodiment.

[0179] like Fig.11 As shown, the light source device 2G of the present embodiment includes a first light source 21 , a light separation optical system 22 , an optical component 23 , a condensing optical system 24 , a light scattering element 25G, and a uniform illumination optical system 30 .

[0180] The light scattering element 25G of this embodiment includes a circular plate 550, a first wavelength conversion layer 551, a light scattering layer 552, and a motor M. The first wavelength conversion layer 551 is arranged in an annular shape in the circumferential direction of the circular plate 550. The light scattering layer 552 is arranged in an annular shape in the circumferential direction of the circular plate 550. The first wavelength conversion layer 551 and the light scattering layer 552 are arranged in a radial direction of the circular plate 550, and the light scattering layer 552 is located at a position radially inward of the first wavelength conversion layer 551. The motor M rotates the circular plate 550 around a rotation axis O passing through the center of the circular plate 550.

[0181] That is, the light scattering element 25G of this embodiment is a rotating light scattering element that changes the incident positions of the first light beam E1 and the second light beam E2 with respect to the first wavelength conversion layer 551 and the light scattering layer 552 with time by rotating the circular plate 550 .

[0182] According to the light source device 2G of the present embodiment, when the rotating light scattering element 25G is used, it is possible to generate white illumination light WL while suppressing an increase in the size of the device structure, similarly to the light source device 2 of the first embodiment.

[0183] In the above embodiment, the structure of the light source device applied to a three-panel projector having light modulators 4R, 4G, and 4B is taken as an example, but the light source device of the present invention can also be applied to a single-panel projector using one light modulator. Furthermore, the light modulator is not limited to the above-mentioned liquid crystal panel, and for example, a digital micromirror device or the like can also be used.

[0184] Hereinafter, a configuration of a modified example in which the light source device 2G of the present embodiment is applied to a single-panel projector will be described.

[0185] Fig.12 2 is a schematic diagram showing a light source device 2H according to a modified example. The same components as those in the eighth embodiment are denoted by the same reference numerals, and their description is omitted.

[0186] like Fig.12 As shown, the light source device 2H of this modified example includes a first light source 21, a light separation optical system 22, an optical component 23, a focusing optical system 24, a light scattering element 25H, a reflector 26, and a uniform illumination optical system 30. In the light source device 2H of this modified example, the white illumination light WL emitted from the light separation optical system 22 is reflected toward the light scattering element 25H by the reflector 26. The light scattering element 25H emits red light, green light, or blue light in time sequence as described later. The uniform illumination optical system 30 is arranged on the optical path of the red light, green light, or blue light emitted from the light scattering element 25H.

[0187] The light scattering element 25H of this embodiment includes a circular plate 650, a first wavelength conversion layer 551, a light scattering layer 552, and a motor M. The first wavelength conversion layer 551 is arranged in an annular shape in the circumferential direction of the circular plate 650. The light scattering layer 552 is arranged in an annular shape in the circumferential direction of the circular plate 650. The first wavelength conversion layer 551 and the light scattering layer 552 are arranged in a radial direction of the circular plate 650, and the light scattering layer 552 is located at a position radially inward of the first wavelength conversion layer 551. The motor M rotates the circular plate 650 around a rotation axis O passing through the center of the circular plate 650.

[0188] The circular plate 650 has a color wheel portion 651 disposed inside the light scattering layer 552. The illumination light WL reflected by the reflector 26 is incident on the color wheel portion 651. The color wheel portion 651 includes a red filter 651R, a green filter 651G, and a blue filter 651B arranged along the circumferential direction. The red filter 651R transmits the red component of the illumination light WL incident from the reflector 26, the green filter 651G transmits the green component of the illumination light WL incident from the reflector 26, and the blue filter 651B transmits the blue component of the illumination light WL incident from the reflector 26.

[0189] In this way, the light source device 2H of this modified example can emit red light R, green light G, and blue light B in the -Y direction in time sequence from the white illumination light WL using the color wheel portion 651 of the light scattering element 25H. Therefore, by driving one light modulation device synchronously with the red light R, green light G, and blue light B incident in time sequence from the light source device 2H, the structure of a single-board type projector can be realized.

[0190] The technical scope of the present invention is not limited to the above-described embodiment, and various modifications can be made without departing from the gist of the present invention. In addition, one aspect of the present invention can be configured by appropriately combining the characteristic portions of the above-described embodiments.

[0191] For example, in the light source device 2E of the sixth embodiment, a case where a part of the blue light E is separated into the third light beam E3 using the beam splitter 27 and the third light beam E3 is incident on the second wavelength conversion layer 353 of the light scattering element 50 is taken as an example, but the fluorescence RL may be generated by causing the second light beam E2 to be incident on the boundary between the first wavelength conversion layer 351 and the second wavelength conversion layer 353 without using the beam splitter 27. Furthermore, the fluorescence RL may be generated by causing the first light beam E1 to be incident on the boundary between the light scattering layer 352 and the second wavelength conversion layer 353.

[0192] In addition, the specific description of the shape, quantity, configuration, material, etc. of each component of the light source device and the projector is not limited to the above-mentioned embodiment and can be appropriately changed. In addition, in the above-mentioned embodiment, an example of mounting the light source device of the present invention on a projector using a liquid crystal panel is shown, but it is not limited to this. The light source device of the present invention can also be applied to a projector using a digital micromirror device as a light modulator. In addition, the projector may not have multiple light modulators, but may only have one light modulator.

[0193] In the above-mentioned embodiment, an example in which the light source device of the present invention is applied to a projector is shown, but the present invention is not limited thereto and can also be applied to lighting equipment, a headlight of a car, and the like.

[0194] Summary of the Disclosure

[0195] The following is a summary of the present disclosure.

[0196] Note 1

[0197] A light source device, comprising: a first light source that emits a first light; a light separation optical system that separates the first light emitted from the first light source into a first light beam and a second light beam that travel in mutually parallel optical paths; an optical component that allows the first light beam and the second light beam incident from the light separation optical system to pass through; a focusing optical system that focuses the first light beam and the second light beam that have passed through the optical component, respectively; and a light scattering element, into which the first light beam and the second light beam emitted from the focusing optical system are respectively incident. The light scattering element is provided at different positions of the light scattering element, the light scattering element comprising: a substrate having a reflecting surface for reflecting light; a first wavelength conversion layer arranged on the reflecting surface for converting the second light beam incident from the focusing optical system into a second light of a wavelength band different from that of the first light; and a light scattering layer arranged on the first wavelength conversion layer in a first direction along the reflecting surface for scattering the first light beam incident from the focusing optical system, the optical component reflecting the light emitted from the light scattering element and passing through the focusing optical system.

[0198] According to the structure of Supplementary Note 1, light emitted from a light scattering element having a light scattering layer and a first wavelength conversion layer and arranged on one side of the optical component can be taken out through a focusing optical system and an optical component. Therefore, the light emitted from the light scattering layer and the first wavelength conversion layer can be parallelized and guided to the optical component by a common focusing optical system. On the other hand, in the case where the light scattering layer and the first wavelength conversion layer are separately arranged in two directions of the optical component, the device structure is enlarged due to the configuration of the focusing optical system on the light scattering layer and the first wavelength conversion layer. According to this structure, it is possible to generate desired light while suppressing the enlargement of the device structure.

[0199] Note 2

[0200] A light source device according to Appendix 1, wherein the optical component comprises: a first optical portion that transmits the first light beam and the second light beam and reflects the second light beam; and a second optical portion that guides the scattered light of the first light beam emitted from the light scattering layer of the light scattering element and passing through the first optical portion to the optical path of the second light beam after being reflected by the first optical portion.

[0201] According to the configuration of Supplementary Note 2, by making the optical paths of the scattered light of the first light flux and the second light flux coincide with each other, it is possible to suppress the occurrence of color unevenness.

[0202] Note 3

[0203] A light source device according to Note 1 or 2, wherein the light separation optical system comprises: a first reflecting element which transmits a portion of the first light emitted from the first light source as the first light beam and reflects another portion of the first light as the second light beam; and a second reflecting element which reflects the second light beam reflected by the first reflecting element toward the optical component.

[0204] According to the configuration of Supplementary Note 3, it is possible to realize a configuration in which the first light emitted from the first light source is separated into the first light beam and the second light beam.

[0205] Note 4

[0206] A light source device according to any one of Notes 1 to 3, wherein the light separation optical system comprises: a first reflecting element which reflects a portion of the first light emitted from the first light source as the first light beam and transmits another portion of the first light as the second light beam; and a second reflecting element which reflects the second light beam that has passed through the first reflecting element toward the optical component.

[0207] According to the configuration of Supplementary Note 4, it is possible to realize a configuration in which the first light emitted from the first light source is separated into the first light beam and the second light beam.

[0208] Note 5

[0209] The light source device according to Supplement 3 or 4, wherein the light source device further comprises a second light source that emits a third light having a wavelength band different from that of the first light and the second light, and the first reflecting element guides the third light to the optical path of the first light beam.

[0210] According to the configuration of Supplementary Note 5, by adding the scattered light of the third light emitted from the second light source in addition to the scattered light of the first light and the second light, it is possible to generate illumination light of a desired color tone.

[0211] Note 6

[0212] The light source device according to any one of Supplementary Notes 1 to 5, wherein the focusing optical system includes a convex lens having a positive refractive power, and the first light beam and the second light beam are incident on different areas of the convex lens.

[0213] According to the structure of Supplementary Note 6, the first light beam and the second light beam can be guided to different positions of the light scattering element while simplifying the structure of the condensing optical system.

[0214] Note 7

[0215] A light source device according to any one of Notes 1 to 6, wherein a distance between a principal point of the light-converging optical system and a light incident surface of the light-scattering element in a direction along an optical axis of the light-converging optical system is different from a focal length of the light-converging optical system.

[0216] According to the configuration of Supplementary Note 7, the condensing optical system can be arranged with respect to the light scattering element so that the first light beam and the second light beam are incident on the light incident surface of the light scattering element in a defocused state.

[0217] Note 8

[0218] The light source device according to Supplementary Note 7, wherein the distance is shorter than a focal length of the focusing optical system.

[0219] According to the configuration of Supplementary Note 8, the distance between the light-collecting optical system and the light-scattering element can be shortened. Therefore, the outer diameter of the light-collecting optical system can be reduced in size, and light emitted from the light-scattering element can be efficiently taken in.

[0220] Note 9

[0221] A light source device according to any one of Notes 1 to 8, wherein the optical component includes: a first region for the first light beam to be incident on; and a second region, which is located on the opposite side of the first region relative to the center of the optical component and is for the second light beam to be incident on, and the first region and the second region are configured to sandwich the optical axis of the focusing optical system.

[0222] When the first region and the second region are arranged on one side of the optical axis, the outer diameter of the condensing optical system increases. According to the configuration of Supplementary Note 9, the condensing optical system can efficiently take in the first and second light beams, thereby suppressing an increase in the outer diameter of the condensing optical system.

[0223] Note 10

[0224] A light source device according to any one of Notes 1 to 9, wherein a first distance between a first position and a second position in a direction intersecting the optical axis of the focusing optical system is shorter than a second distance between a third position and the second position in a direction intersecting the optical axis, wherein the first position is an incident position of the second light beam in the light scattering element, the second position is an intersection of the optical axis and the light scattering element, and the third position is an incident position of the first light beam in the light scattering element.

[0225] According to the structure of Supplementary Note 10, the optical axis can be located on the first wavelength conversion layer, and the second light beam can be incident at a position closer to the optical axis. That is, the emission center of the second light is close to the optical axis of the focusing optical system, so the focusing optical system can efficiently take in the second light emitted at a larger radiation angle.

[0226] Note 11

[0227] The light source device according to any one of Supplementary Notes 1 to 10, wherein the light scattering element further comprises a second wavelength conversion layer that converts the second light beam into a third light having a wavelength band different from that of the first light and the second light.

[0228] According to the configuration of Supplementary Note 11, by adding the third light in addition to the scattered light of the first light and the second light, it is possible to generate illumination light of a desired color tone.

[0229] Note 12

[0230] A light source device according to any one of Notes 1 to 11, wherein the second wavelength conversion layer is arranged in a second direction of the first wavelength conversion layer intersecting the first direction, the light separation optical system further has a beam separation portion, which separates a portion of the first light into a third light beam traveling in an optical path parallel to the first light beam and the second light beam, the beam separation portion comprising: a third reflecting element, which reflects a portion of the first light as the third light beam in the second direction and allows another portion of the first light to pass as the second light beam; and a fourth reflecting element, which reflects the third light beam incident from the third reflecting element toward the optical component, the focusing optical system causes the third light beam reflected by the fourth reflecting element and passing through the optical component to be incident on the second wavelength conversion layer.

[0231] According to the structure of Supplementary Note 12, it is possible to realize a structure in which the third light beam separated from the first light is incident on the second wavelength conversion layer arranged in the second direction of the first wavelength conversion layer to generate the second light.

[0232] Note 13

[0233] A light source device according to any one of Notes 1 to 12, wherein the second wavelength conversion layer is arranged on the side of the first wavelength conversion layer opposite to the light scattering layer, and the focusing optical system causes the second light beam to be incident on the light scattering element in a manner that the second light beam crosses the boundary between the first wavelength conversion layer and the second wavelength conversion layer.

[0234] According to the structure of Supplementary Note 13, it is possible to realize a structure in which the third light beam separated from the first light is incident on the second wavelength conversion layer disposed on the side of the first wavelength conversion layer opposite to the light scattering layer to generate the second light.

[0235] Note 14

[0236] A light source device, comprising: a first light source that emits a first light consisting of coherent light; a second light source that emits a second light consisting of incoherent light; an optical component that allows the first light and the second light that are incident in parallel to each other to pass through; a focusing optical system that focuses the first light and the second light that have passed through the optical component, respectively; and a light scattering element, the first light and the second light emitted from the focusing optical system are respectively incident on different positions of the light scattering element, the light scattering element comprising: a substrate having a reflecting surface for reflecting light; a first wavelength conversion layer that is arranged on the reflecting surface, The first light incident from the focusing optical system is converted into a third light of a wavelength band different from the wavelength band of the first light and the wavelength band of the second light; and a light scattering layer, which is arranged in the direction along the reflecting surface of the first wavelength conversion layer, so as to scatter the second light incident from the focusing optical system, the optical component reflects the light emitted from the light scattering element and after passing through the focusing optical system, and the light scattering degree of the light scattering layer is adjusted so that the angular distribution of the third light emitted from the first wavelength conversion layer is close to the angular distribution of the scattered light of the second light emitted from the light scattering layer.

[0237] According to the structure of Supplementary Note 14, by making the first light and the second light enter the light scattering layer and the first wavelength conversion layer of the light scattering element in an appropriate combination, the expansion of the second angular distribution can be suppressed and the cost of the light scattering element can be reduced.

[0238] Note 15

[0239] A projector comprising: a light source device as described in any one of Notes 1 to 14; a light modulation device that modulates illumination light emitted from the light source device according to image information; and a projection optical device that projects image light modulated by the light modulation device.

[0240] According to the structure of Supplementary Note 15, a small projector can be realized.

Claims

1. A light source device, comprising: a first light source that emits a first light; a light separation optical system that separates the first light emitted from the first light source into a first light beam and a second light beam that travel in mutually parallel optical paths; an optical component that allows the first light beam and the second light beam incident from the light separation optical system to pass therethrough; a focusing optical system for focusing the first light beam and the second light beam respectively transmitted through the optical component; and a light scattering element, wherein the first light beam and the second light beam emitted from the light-collecting optical system are incident on different positions of the light scattering element, respectively; The light scattering element comprises: a substrate having a reflecting surface for reflecting light; a first wavelength conversion layer disposed on the reflecting surface and converting the second light beam incident from the light-condensing optical system into a second light of a wavelength band different from that of the first light; and a light scattering layer disposed on the first wavelength conversion layer in a first direction along the reflecting surface and scattering the first light beam incident from the light-condensing optical system. The optical component reflects the light emitted from the light scattering element and passing through the light collecting optical system.

2. The light source device according to claim 1, wherein: The optical component has: a first optical portion that transmits the first light beam and the second light beam and reflects the second light beam; and The second optical portion guides scattered light of the first light flux emitted from the light scattering layer of the light scattering element and passing through the first optical portion to an optical path of the second light reflected by the first optical portion.

3. The light source device according to claim 1 or 2, wherein: The light separation optical system comprises: a first reflecting element that transmits a portion of the first light emitted from the first light source as the first light beam and reflects another portion of the first light as the second light beam; as well as The second reflecting element reflects the second light beam reflected by the first reflecting element toward the optical component.

4. The light source device according to claim 1 or 2, wherein: The light separation optical system comprises: a first reflecting element that reflects a portion of the first light emitted from the first light source as the first light beam and transmits another portion of the first light as the second light beam; as well as The second reflecting element reflects the second light beam transmitted through the first reflecting element toward the optical component.

5. The light source device according to claim 3, wherein: The light source device further includes a second light source that emits a third light having a wavelength band different from that of the first light and the second light. The first reflecting element guides the third light to the optical path of the first light beam.

6. The light source device according to claim 1 or 2, wherein: The focusing optical system comprises a convex lens with positive refractive power. The first light beam and the second light beam are incident on different areas of the convex lens.

7. The light source device according to claim 1 or 2, wherein: A distance between a principal point of the condensing optical system and a light incident surface of the light scattering element in a direction along an optical axis of the condensing optical system is different from a focal length of the condensing optical system.

8. The light source device according to claim 7, wherein: The distance is shorter than the focal length of the condensing optical system.

9. The light source device according to claim 1 or 2, wherein: The optical component includes: a first region for the first light beam to be incident on; and a second region for the second light beam to be incident on, located on the opposite side of the first region relative to the center of the optical component. The first region and the second region are arranged so as to sandwich the optical axis of the condensing optical system.

10. The light source device according to claim 1 or 2, wherein: A first distance between a first position and a second position in a direction intersecting the optical axis of the focusing optical system is shorter than a second distance between a third position and the second position in a direction intersecting the optical axis, wherein the first position is the incident position of the second light beam in the light scattering element, the second position is the intersection of the optical axis and the light scattering element, and the third position is the incident position of the first light beam in the light scattering element.

11. The light source device according to claim 1 or 2, wherein: The light scattering element further includes a second wavelength conversion layer that converts the second light beam into a third light having a wavelength band different from that of the first light and the second light.

12. The light source device according to claim 11, wherein: The second wavelength conversion layer is arranged in a second direction intersecting the first direction of the first wavelength conversion layer. The light separation optical system further includes a beam separation unit that separates a portion of the first light into a third light beam that travels in an optical path parallel to the first light beam and the second light beam. The beam splitting section includes: a third reflecting element that reflects a portion of the first light as the third beam toward the second direction and transmits another portion of the first light as the second beam; and a fourth reflecting element that reflects the third light beam incident from the third reflecting element toward the optical component, The condensing optical system causes the third light beam reflected by the fourth reflecting element and passing through the optical member to be incident on the second wavelength conversion layer.

13. The light source device according to claim 11, wherein: The second wavelength conversion layer is disposed on a side of the first wavelength conversion layer opposite to the light scattering layer. The condensing optical system causes the second light beam to be incident on the light scattering element so that the second light beam crosses a boundary between the first wavelength conversion layer and the second wavelength conversion layer.

14. A light source device comprising: a first light source that emits a first light consisting of coherent light; a second light source that emits a second light consisting of incoherent light; an optical component that allows the first light and the second light that are incident parallel to each other to pass; a focusing optical system that focuses the first light and the second light that have passed through the optical component, respectively; and a light scattering element, wherein the first light and the second light emitted from the light-collecting optical system are incident on different positions of the light scattering element, respectively; The light scattering element comprises: a substrate having a reflecting surface for reflecting light; a first wavelength conversion layer disposed on the reflecting surface and converting the first light incident from the light-collecting optical system into a third light having a wavelength band different from the wavelength band of the first light and the wavelength band of the second light; and a light scattering layer disposed on the first wavelength conversion layer in a direction along the reflecting surface and scattering the second light incident from the light-collecting optical system. The optical component reflects the light emitted from the light scattering element and passing through the focusing optical system. The degree of light scattering of the light scattering layer is adjusted so that the angular distribution of the third light emitted from the first wavelength conversion layer becomes close to the angular distribution of scattered light of the second light emitted from the light scattering layer.

15. A projector comprising: The light source device according to claim 1 or 2; a light modulation device for modulating the illumination light emitted from the light source device according to image information; and A projection optical device projects the image light modulated by the light modulation device.

Images