Light source device and projector

Abstract

To provide a light source device that outputs light with less loss, and a projector.SOLUTION: A light source device of the present invention comprises: a light emitting device; a light guide member; an angle conversion member; and a first joint layer and a second joint layer joining the light guide member and the angle conversion member to each other. The light guide member has a first surface and a second surface located on the opposite sides to each other in a longitudinal direction of the light guide member, and a first side face in contact with the first surface and the second surface. Light guided by the light guide member is emitted from the first surface, and light emitted from the light emitting device is incident on the light guide member from the first side face. The angle conversion member has an incident end face, an emission end face, and a second side face in contact with the incident end face and the emission end face. The first joint layer is provided in at least part of a space between the first surface and the incident end face, and the second joint layer is provided over the first joint layer from at least a portion of the first side face to at least a portion of the second side face.SELECTED DRAWING: Figure 6

Description

[Technical field]

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

[0002] As a light source device for use in a projector, a light source device has been proposed that utilizes fluorescence emitted from a phosphor when the phosphor is irradiated with excitation light emitted from a light emitting element. The following Patent Document 1 discloses a light source device that includes a solid-state light source, a light guide that converts the wavelength of the light emitted from the solid-state light source, and a collimator optically coupled to the light guide. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] International Publication No. 2020 / 078790 Summary of the Invention [Problem to be solved by the invention]

[0004] In the light source device of Patent Document 1, the collimator is bonded to the end face of the light guide. An adhesive is generally used to bond the collimator and the light guide. In this configuration, the area of ​​the end face of the light guide is small compared to the size of the collimator, so the bonding area is small and there is a risk that the desired bonding strength cannot be obtained. In addition, when light incident on the collimator from the light guide passes through the adhesive at a high light density, the temperature of the adhesive increases, causing the adhesive to deteriorate, and the bonding strength may decrease. If the collimator peels off from the light guide, there is a problem that the desired light output cannot be obtained as a light source device.

[0005] Although the above description has been given taking a light source device with wavelength conversion as an example, a light source device without wavelength conversion has the same problem. It is desired to provide a light source device that has little loss of output light and can emit light with a desired intensity. [Means for solving the problem]

[0006] In order to solve the above problems, a light source device according to one embodiment of the present invention includes a light emitting element that emits light, a light guiding member that guides the light emitted from the light emitting element, an angle conversion member that converts the angular distribution of the light emitted from the light guiding member, and a first bonding layer and a second bonding layer that bond the light guiding member and the angle conversion member. The light guiding member has a first surface and a second surface that are located opposite each other in the longitudinal direction of the light guiding member, and a first side surface that contacts each of the first surface and the second surface. The light that is guided through the light guiding member is emitted from the first surface, and the light emitted from the light emitting element is incident on the light guiding member from the first side surface. The angle conversion member has an incident end surface on which the light emitted from the light guiding member is incident, an exit end surface that emits the light incident from the incident end surface, and a second side surface that contacts each of the incident end surface and the exit end surface. The first bonding layer is provided at least partially between the first surface and the incident end surface, and the second bonding layer is provided across the first bonding layer and over at least a portion of the first side surface and at least a portion of the second side surface.

[0007] A projector of one embodiment of the present invention comprises a light source device of one embodiment of the present invention, a light modulation device that modulates light emitted from the light source device in accordance with image information, and a projection optical device that projects the light modulated by the light modulation device. [Brief description of the drawings]

[0008] [Figure 1] FIG. 1 is a schematic configuration diagram of a projector according to a first embodiment. [Diagram 2] FIG. 2 is a schematic configuration diagram of a first illumination device according to the first embodiment. [Diagram 3] FIG. 1 is a perspective view of a light source device according to a first embodiment. [Figure 4] FIG. 2 is a plan view of the light source device. [Diagram 5] 4 is a cross-sectional view of the light source device taken along line VV in FIG. [Figure 6]6 is an enlarged cross-sectional side view of the first bonding layer and the second bonding layer taken along line VI-VI in FIG. 3. [Figure 7] FIG. 11 is a perspective view showing a main part of a light source device according to a second embodiment. [Figure 8] FIG. 8 is a side cross-sectional view taken along line VIII-VIII in FIG. 7. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0009] [First embodiment] Hereinafter, a first embodiment of the present invention will be described with reference to the drawings. The projector of this embodiment is an example of a projector that uses a liquid crystal panel as a light modulation device. In the drawings, the dimensions of the components may be shown on different scales in order to make the components easier to see.

[0010] FIG. 1 is a schematic configuration diagram of a projector 1 of the present embodiment. As shown in Fig. 1, the projector 1 of this embodiment is a projection type image display device that displays a color image on a screen (projection surface) SCR. The projector 1 includes three light modulation devices corresponding to the respective colors of red light LR, green light LG, and blue light LB.

[0011] The projector 1 includes a first illumination device 20, a second illumination device 21, a color separation optical system 3, a light modulation device 4R, a light modulation device 4G, a light modulation device 4B, a light combining element 5, and a projection optical device 6.

[0012] The first illumination device 20 emits yellow fluorescence Y toward the color separation optical system 3. The second illumination device 21 emits blue light LB toward the light modulation device 4B. Detailed configurations of the first illumination device 20 and the second illumination device 21 will be described later.

[0013] In the following, in the drawings, an XYZ orthogonal coordinate system is used for explanation as necessary. The Z axis is an axis along the up-down direction of the projector 1. The X axis is an axis parallel to the optical axis AX1 of the first lighting device 20 and the optical axis AX2 of the second lighting device 21, and is an axis along the front-rear direction of the projector 1. The Y axis is an axis perpendicular to the X axis and the Z axis, and is an axis along the left-right direction of the projector 1. These notations are for explaining the arrangement relationship of each component of the projector 1, and do not limit the installation posture or direction of the projector 1. The optical axis AX1 of the first lighting device 20 is the central axis of the fluorescent light Y emitted from the first lighting device 20. The optical axis AX2 of the second lighting device 21 is the central axis of the blue light LB emitted from the second lighting device 21.

[0014] The color separation optical system 3 separates the yellow fluorescence Y emitted from the first illumination device 20 into red light LR and green light LG. The color separation optical system 3 includes a dichroic mirror 7, a first reflecting mirror 8a, and a second reflecting mirror 8b.

[0015] The dichroic mirror 7 separates the fluorescence Y into red light LR and green light LG. The dichroic mirror 7 transmits the red light LR and reflects the green light LG. The second reflecting mirror 8b is disposed in the optical path of the green light LG. The second reflecting mirror 8b reflects the green light LG reflected by the dichroic mirror 7 toward the optical modulation device 4G. The first reflecting mirror 8a is disposed in the optical path of the red light LR. The first reflecting mirror 8a reflects the red light LR transmitted through the dichroic mirror 7 toward the optical modulation device 4R.

[0016] On the other hand, the blue light LB emitted from the second illumination device 21 is reflected by the reflecting mirror 9 towards the light modulation device 4B.

[0017] The configuration of the second illumination device 21 will be described below. The second illumination device 21 includes a light source unit 81, a condenser lens 82, a diffusion plate 83, a rod lens 86, and a relay lens 87. The light source unit 81 is composed of at least one semiconductor laser. The light source unit 81 emits blue light LB composed of laser light. Note that the light source unit 81 is not limited to a semiconductor laser, and may be composed of an LED that emits blue light.

[0018] The condenser lens 82 is composed of a convex lens. The condenser lens 82 causes the blue light LB emitted from the light source unit 81 to enter the diffusion plate 83 in a substantially condensed state. The diffusion plate 83 diffuses the blue light LB emitted from the condenser lens 82 with a predetermined diffusion degree, and generates blue light LB having a substantially uniform light distribution similar to that of the fluorescent light Y emitted from the first lighting device 20. As the diffusion plate 83, for example, ground glass made of optical glass is used.

[0019] The blue light LB diffused by the diffusion plate 83 is incident on the rod lens 86. The rod lens 86 has a prismatic shape extending along the optical axis AX2 direction of the second illumination device 21. The rod lens 86 has a light incident end face 86a and a light exit end face 86b located on the opposite side to the light incident end face 86a. The diffusion plate 83 is fixed to the light incident end face 86a of the rod lens 86 via an optical adhesive (not shown). It is desirable that the refractive index of the diffusion plate 83 and the refractive index of the rod lens 86 match as closely as possible.

[0020] The blue light LB is propagated while being totally reflected inside the rod lens 86, and is emitted from the light emitting end surface 86b with the uniformity of the illuminance distribution being enhanced. The blue light LB emitted from the rod lens 86 is incident on the relay lens 87. The relay lens 87 causes the blue light LB, whose uniformity of the illuminance distribution has been enhanced by the rod lens 86, to be incident on the reflecting mirror 9.

[0021] The shape of the light exit end surface 86b of the rod lens 86 is a rectangle that is approximately similar to the shape of the image forming area of ​​the light modulation device 4B. This allows the blue light LB exiting from the rod lens 86 to efficiently enter the image forming area of ​​the light modulation device 4B.

[0022] The light modulation device 4R modulates the red light LR according to image information to form image light corresponding to the red light LR. The light modulation device 4G modulates the green light LG according to image information to form image light corresponding to the green light LG. The light modulation device 4B modulates the blue light LB according to image information to form image light corresponding to the blue light LB.

[0023] For example, a transmissive liquid crystal panel is used for each of the light modulation devices 4R, 4G, and 4B. A polarizing plate (not shown) is disposed on the entrance side and exit side of each of the liquid crystal panels. The polarizing plate transmits linearly polarized light in a specific direction.

[0024] A field lens 10R is disposed on the incident side of the optical modulation device 4R. A field lens 10G is disposed on the incident side of the optical modulation device 4G. A field lens 10B is disposed on the incident side of the optical modulation device 4B. The field lens 10R collimates the chief ray of the red light LR incident on the optical modulation device 4R. The field lens 10G collimates the chief ray of the green light LG incident on the optical modulation device 4G. The field lens 10B collimates the chief ray of the blue light LB incident on the optical modulation device 4B.

[0025] The light combining element 5 receives the image light emitted from the light modulation device 4R, the light modulation device 4G, and the light modulation device 4B, combines the image light corresponding to the red light LR, the green light LG, and the blue light LB, and emits the combined image light toward the projection optical device 6. The light combining element 5 may be, for example, a cross dichroic prism.

[0026] The projection optical device 6 is composed of a plurality of projection lenses. The projection optical device 6 enlarges and projects the image light combined by the light combining element 5 onto the screen SCR. As a result, an image is displayed on the screen SCR.

[0027] The configuration of the first illumination device 20 will be described below. FIG. 2 is a schematic diagram showing a schematic configuration of the first illumination device 20. As shown in FIG. As shown in FIG. 2, the first illumination device 20 includes a light source device 30, a collimating optical system 63, an integrator optical system 31, a polarization conversion element 32, and a superimposing optical system 33.

[0028] Fig. 3 is a perspective view showing a schematic configuration of light source device 30. Fig. 4 is a plan view of light source device 30. Fig. 5 is a cross-sectional view of light source device 30 taken along line VV in Fig. 3. Fig. 6 is an enlarged side cross-sectional view of the vicinity of first bonding layer 41 and second bonding layer 42 taken along line VI-VI in Fig. 3.

[0029] As shown in Figures 3 to 6, the light source device 30 of this embodiment includes a wavelength conversion member 50, a light source unit 51, an angle conversion member 52, a mirror 53, a support member 54, a position control member 65, a pressing member 90, a first bonding layer 41, and a second bonding layer 42.

[0030] The wavelength conversion member 50 has a rectangular prism shape extending along the X-axis and has six faces. The sides of the wavelength conversion member 50 extending along the X-axis are longer than the sides extending along the Y-axis and the Z-axis. Therefore, the direction in which the X-axis extends corresponds to the longitudinal direction of the wavelength conversion member 50. The lengths of the sides extending along the Y-axis and the Z-axis are equal. That is, the cross-sectional shape of the wavelength conversion member 50 cut along a plane along the YZ plane perpendicular to the X-axis is a square. Note that the cross-sectional shape of the wavelength conversion member 50 cut along a plane along the YZ plane may be a rectangle. As an example of the size of the wavelength conversion member 50, the sides extending along the Y-axis and the Z-axis have lengths of, for example, 1 mm, and the sides extending along the X-axis have lengths of, for example, 50 mm.

[0031] The wavelength conversion member 50 has a first surface 50a, a second surface 50b, a third surface 50c, a fourth surface 50d, a fifth surface 50e, and a sixth surface 50f. The first surface 50a and the second surface 50b are perpendicular to the X-axis along the longitudinal direction of the wavelength conversion member 50 and are located on opposite sides of the X-axis. In this embodiment, the first surface 50a is located on one side in the X-axis direction, that is, the +X side, and the second surface 50b is located on the opposite side in the X-axis direction, that is, the -X side.

[0032] The third surface 50c and the fourth surface 50d are orthogonal to the first surface 50a and the second surface 50b, and are located on opposite sides to each other in the Y axis that is orthogonal to the X axis along the longitudinal direction of the wavelength conversion member 50. In this embodiment, the third surface 50c is located on one side in the Y axis direction, that is, the -Y side, and the fourth surface 50d is located on the other side in the Y axis direction, that is, the +Y side.

[0033] The fifth surface 50e and the sixth surface 50f are perpendicular to the third surface 50c and the fourth surface 50d, and are located on opposite sides of the Z axis perpendicular to the X axis and the Y axis. In this embodiment, the fifth surface 50e is located in the +Z direction, which is one side of the Z axis direction, and the sixth surface 50f is located in the -Z direction, which is the other side of the Z axis direction.

[0034] In the following description, when the third surface 50c, the fourth surface 50d, the fifth surface 50e, and the sixth surface 50f are not distinguished from each other, they may be simply referred to as side surfaces 50c, 50d, 50e, and 50f. The side surfaces 50c, 50d, 50e, and 50f in this embodiment correspond to the first side surface of the claims.

[0035] The wavelength conversion member 50 includes at least a phosphor, and converts the excitation light E having a first wavelength band emitted from the light emitting element 56 of the light source unit 51 into fluorescence Y having a second wavelength band different from the first wavelength band. The excitation light E enters the wavelength conversion member 50 from the third surface 50c. The fluorescence Y is guided inside the wavelength conversion member 50 and then emitted from the first surface 50a. The excitation light E in this embodiment corresponds to the first light in the claims. The fluorescence Y in this embodiment corresponds to the second light in the claims.

[0036] The wavelength conversion member 50 contains a ceramic phosphor made of a polycrystalline phosphor that converts the wavelength of the excitation light E into the fluorescence Y. The second wavelength band of the fluorescence Y is, for example, a yellow wavelength band of 490 to 750 nm. That is, the fluorescence Y is yellow fluorescence containing a red light component and a green light component. The wavelength conversion member 50 may contain a single crystal phosphor instead of the polycrystalline phosphor. Alternatively, the wavelength conversion member 50 may be made of fluorescent glass. Alternatively, the wavelength conversion member 50 may be made of a material in which a large number of phosphor particles are dispersed in a binder made of glass or resin. The wavelength conversion member 50 made of this type of material converts the excitation light E into the fluorescence Y.

[0037] Specifically, the material of the wavelength conversion member 50 includes, for example, an yttrium aluminum garnet (YAG) phosphor. Taking YAG:Ce, which contains cerium (Ce) as an activator, as an example, the material of the wavelength conversion member 50 includes YAG:Ce, which contains cerium (Ce) as an activator. 2 O 3 , Al 2 O 3 , CEO 3 Materials that can be used include those obtained by mixing raw material powders containing the above-mentioned constituent elements and subjecting them to a solid-phase reaction; Y-Al-O amorphous particles obtained by wet processes such as the coprecipitation method and the sol-gel method; and YAG particles obtained by gas-phase processes such as the spray drying method, the flame pyrolysis method, and the thermal plasma method.

[0038] The light source unit 51 has a substrate 55, a plurality of light-emitting elements 56, and wiring (not shown). The light source unit 51 may also have other optical members such as a light guide plate, a diffusion plate, and a lens. The plurality of light-emitting elements 56 are provided on one surface of the substrate 55. The light source unit 51 of this embodiment has a plurality of light-emitting elements 56, but the number of the light-emitting elements 56 is not particularly limited.

[0039] The light emitting element 56 has a light emitting surface 56a and emits excitation light E of a first wavelength band from the light emitting surface 56a. The light emitting element 56 is, for example, a light emitting diode (LED). The light emitting element 56 is disposed facing the third surface 50c of the wavelength conversion member 50 and emits excitation light E toward the third surface 50c. The first wavelength band is, for example, a wavelength band from blue to purple of 400 nm to 480 nm, and the peak wavelength is, for example, 445 nm. In this way, the light source unit 51 is provided facing the third surface 50c, which is one of the four side surfaces 50c, 50d, 50e, and 50f along the longitudinal direction of the wavelength conversion member 50.

[0040] The support member 54 has a groove 154 that supports the wavelength conversion member 50. The support member 54 supports the wavelength conversion member 50 inside the groove 154, thereby diffusing and releasing heat generated in the wavelength conversion member 50 to the outside. For this reason, it is desirable that the support member 54 is made of a material that has a predetermined strength and high thermal conductivity. As a material for the support member 54, for example, a metal such as aluminum, iron, or stainless steel is used, and in particular, it is desirable to use an aluminum alloy such as 6061 series. A specific configuration of the support member 54 will be described later.

[0041] The position restricting member 65, together with the pressing member 90 described later, restricts the position of the wavelength conversion member 50 relative to the support member 54. As shown in FIG. 4, the position restricting member 65 restricts the movement of the wavelength conversion member 50 to the +Z side and the -Z side along the Z-axis direction. The position restricting member 65 is made of a pair of members, and is accommodated in a first accommodation groove portion 541 provided on both sides of the groove portion 154 of the support member 54. The position restricting member 65 is fixed to the support member 54 by a screw 97. In this embodiment, the pair of position restricting members 65 are provided at two locations, one on the side close to the first surface 50a of the wavelength conversion member 50 and the other on the side close to the second surface 50b, but the number and installation positions of the position restricting members 65 are not limited.

[0042] As shown in FIG. 5, the pressing member 90 restricts the movement of the wavelength conversion member 50 in the Y-axis direction relative to the support member 54 inside the groove 154. The pressing member 90 is disposed facing the support surface 54s of the groove 154. As a result, the pressing member 90 restricts the wavelength conversion member 50 from moving to the -Y side inside the groove 154, and presses the wavelength conversion member 50 toward the support surface 54s. The pressing member 90 is made of a material capable of elastic deformation. Specifically, the pressing member 90 is made of a leaf spring made of a stainless steel material such as SUS304. As shown in FIG. 4, the pressing member 90 is accommodated in a second accommodation groove 542 provided in the support member 54.

[0043] In this embodiment, two pressing members 90 are used, but the number of pressing members 90 is not particularly limited. It is desirable that each of the two pressing members 90 is disposed at a position that does not overlap with the light emitting element 56 of the light source unit 51. With this configuration, the excitation light E emitted from the light emitting element 56 is not blocked by the pressing members 90. Each of the two pressing members 90 presses the wavelength conversion member 50 against the support surface 54s of the support member 54 at each installation position. The pressing members 90 are fixed to the support member 54 by screws 96.

[0044] The mirror 53 is provided on the second surface 50b of the wavelength conversion member 50. The mirror 53 guides light inside the wavelength conversion member 50 and reflects the fluorescence Y that reaches the second surface 50b. The mirror 53 is configured separately from the wavelength conversion member 50 and is provided in contact with the second surface 50b of the wavelength conversion member 50. The mirror 53 has a reflection surface 53r in which a metal film or a dielectric multilayer film is formed on one surface of a plate made of metal or the like. A pressing member for pressing the mirror 53 against the second surface 50b of the wavelength conversion member 50 may be further provided. The mirror 53 may be made of a metal film or a dielectric multilayer film directly formed on the second surface 50b of the wavelength conversion member 50.

[0045] In the light source device 30, when the excitation light E emitted from the light source unit 51 is incident on the wavelength conversion member 50, the phosphor contained in the wavelength conversion member 50 is excited, and the fluorescence Y is emitted from an arbitrary light-emitting point. The fluorescence Y travels in all directions from an arbitrary light-emitting point, and the fluorescence Y traveling toward the four side surfaces 50c, 50d, 50e, and 50f travels toward the first surface 50a or the second surface 50b while repeating total reflection at multiple points on the side surfaces 50c, 50d, 50e, and 50f. The first surface 50a emits the fluorescence Y that has been guided inside the wavelength conversion member 50. In the case of this embodiment, the fluorescence Y traveling toward the first surface 50a is emitted from the first surface 50a and enters the angle conversion member 52 provided on the first surface 50a. The fluorescence Y traveling toward the second surface 50b is reflected by the mirror 53 and then travels toward the first surface 50a.

[0046] Of the excitation light E incident on the wavelength conversion member 50, a portion of the excitation light E that is not used to excite the phosphor is reflected by the members surrounding the wavelength conversion member 50, including the light emitting element 56 of the light source unit 51, or by the mirror 53 provided on the second surface 50b. Therefore, a portion of the excitation light E is trapped inside the wavelength conversion member 50 and reused.

[0047] 4, the support member 54 is a plate-like member having a rectangular planar shape and including a groove portion 154, a first accommodating groove portion 541, and a second accommodating groove portion 542. The groove portion 154 extends in the X-axis direction along the longitudinal direction of the wavelength conversion member 50, and accommodates the wavelength conversion member 50.

[0048] 5, the groove 154 has a cross section perpendicular to the X-axis direction that is substantially U-shaped. The groove 154 has a support surface 54s, a first wall surface 54a, and a second wall surface 54b. The groove 154 is formed by cutting the material of the support member 54, which is a metal such as aluminum, iron, or stainless steel.

[0049] The support surface 54s corresponds to the bottom surface of the groove portion 154. In the case of this embodiment, the support surface 54s is a surface extending parallel to the XZ plane, abuts against the fourth surface 50d of the wavelength conversion member 50, and supports the fourth surface 50d. The first wall surface 54a corresponds to one side surface of the groove portion 154. The first wall surface 54a faces the fifth surface 50e of the wavelength conversion member 50 and is spaced from the fifth surface 50e. That is, a gap is provided between the first wall surface 54a and the fifth surface 50e of the wavelength conversion member 50. The second wall surface 54b corresponds to the other side surface of the groove portion 154. The second wall surface 54b faces the sixth surface 50f of the wavelength conversion member 50 and is spaced from the sixth surface 50f. That is, a gap is provided between the second wall surface 54b and the sixth surface 50f of the wavelength conversion member 50.

[0050] The first wall surface 54a has a first portion 54a1 located on the side farther from the support surface 54s and a second portion 54a2 located on the side closer to the support surface 54s. The first portion 54a1 extends in a direction perpendicular to the support surface 54s, i.e., parallel to the XY plane. The second portion 54a2 is inclined so as to approach the fifth surface 50e from the first portion 54a1 side toward the support surface 54s side. In other words, the distance between the second portion 54a2 on the side closer to the support surface 54s and the fifth surface 50e is smaller than the distance between the second portion 54a2 on the side closer to the support surface 54s and the fifth surface 50e on the side closer to the first portion 54a1.

[0051] The second wall surface 54b has a third portion 54b3 located on the side farther from the support surface 54s and a fourth portion 54b4 located on the side closer to the support surface 54s. The third portion 54b3 extends in a direction perpendicular to the support surface 54s, i.e., parallel to the XY plane. The fourth portion 54b4 is inclined so as to approach the sixth surface 50f from the third portion 54b3 side toward the support surface 54s side. In other words, the distance between the fourth portion 54b4 on the side closer to the support surface 54s and the sixth surface 50f is smaller than the distance between the fourth portion 54b4 on the side closer to the third portion 54b3 and the sixth surface 50f.

[0052] Each of the first wall surface 54a and the second wall surface 54b is made of a surface of a metal such as aluminum, iron, or stainless steel, which is a material of the support member 54. More specifically, each of the first wall surface 54a and the second wall surface 54b is made of a processed surface that is a mirror-finished surface of the above-mentioned metal surface. As a result, each of the first wall surface 54a and the second wall surface 54b has light reflectivity and reflects the incident excitation light E. Note that each of the first wall surface 54a and the second wall surface 54b may be made of another metal film or a dielectric multilayer film formed on the surface of a metal such as aluminum, iron, or stainless steel.

[0053] The first wall surface 54a and the second wall surface 54b of the groove portion 154 need to be mirror-finished as described above. Therefore, the portion where the groove portion 154 is provided is required to have higher processing accuracy than other portions of the support member 54. For this reason, the portion of the support member 54 where the groove portion 154 is provided may be made of a different member, and one support member 54 may be constructed by combining with another member that forms the portion other than the groove portion 154. In other words, the support member 54 may be constructed by combining a plurality of members. In this way, since the peripheral portion of the groove portion 154 is formed of a different member, the workability and processing accuracy of the first wall surface 54a and the second wall surface 54b of the groove portion 154 can be easily improved.

[0054] The dimension W1 of the light-emitting surface 56a of the light-emitting element 56 along the Z-axis direction is larger than the width B2 of the wavelength conversion member 50 along the Z-axis direction. The width of the wavelength conversion member 50 in this embodiment in the Z-axis direction is equal throughout the longitudinal direction. As a result, both ends of the light-emitting surface 56a of the light-emitting element 56 protrude outside the third surface 50c of the wavelength conversion member 50 in the Z-axis direction. Specifically, both ends of the light-emitting surface 56a of the light-emitting element 56 protrude to positions overlapping the gap between the fifth surface 50e and the first wall surface 54a and the gap between the sixth surface 50f and the second wall surface 54b. In other words, when the light-emitting surface 56a is viewed along the Y-axis direction from the support surface 54s, a part of the light-emitting surface 56a overlaps with the third surface 50c, and another part of the light-emitting surface 56a overlaps with the gap between the fifth surface 50e and the first wall surface 54a and the gap between the sixth surface 50f and the second wall surface 54b.

[0055] The width D2 of the support surface 54s of the support member 54 along the Z-axis direction is larger than the width B2 of the wavelength conversion member 50 along the Z-axis direction. As a result, both ends of the support surface 54s in the Z-axis direction protrude outside the fourth surface 50d of the wavelength conversion member 50. In other words, when the support surface 54s is viewed from the light-emitting surface 56a along the Y-axis direction, a part of the support surface 54s overlaps with the fourth surface 50d, and another part of the support surface 54s is exposed outside the fourth surface 50d. In this way, the support surface 54s has an exposed portion 54r exposed to the outside of the wavelength conversion member 50.

[0056] According to the light source device 30 of this embodiment, a part of the excitation light E2 emitted from the light emitting surface 56a of the light emitting element 56 passes through the gap between the fifth surface 50e of the wavelength conversion member 50 and the first portion 54a1, and then enters the second portion 54a2 inclined with respect to the support surface 54s. At this time, the excitation light E2 is reflected by the second portion 54a2 and enters the fifth surface 50e of the wavelength conversion member 50. In this way, the excitation light E2 passing through the gap between the fifth surface 50e of the wavelength conversion member 50 and the first wall surface 54a is easily incident on the fifth surface 50e, so that the amount of the excitation light E reflected by the support surface 54s and returning to the light source unit 51 can be reduced. In addition, a part of the excitation light E is reflected by the first portion 54a1 extending perpendicularly to the support surface 54s and enters the fifth surface 50e of the wavelength conversion member 50. The same applies to the excitation light E2 entering the gap between the sixth surface 50f and the second wall surface 54b of the wavelength conversion member 50. This makes it possible to realize a light source device 30 in which the utilization efficiency of the excitation light E is high and fluorescence Y having a desired intensity can be easily obtained.

[0057] 4, the first accommodating groove 541 is provided on the upper surface of the supporting member 54, and is a groove recessed into the upper surface of the supporting member 54. The first accommodating groove 541 is provided on both sides in the Z-axis direction of the groove 154. The first accommodating groove 541 accommodates a position restricting member 65 that restricts the position of the wavelength conversion member 50 in the Z-axis direction.

[0058] The second accommodating groove 542 is provided on the upper surface of the supporting member 54, and is a groove recessed into the upper surface of the supporting member 54. The second accommodating groove 542 is provided on both sides in the Z-axis direction of the groove 154. The second accommodating groove 542 accommodates the pressing member 90 that presses the wavelength conversion member 50 toward the supporting surface 54s of the supporting member 54.

[0059] The angle conversion member 52 is provided on the first surface 50a of the wavelength conversion member 50. The angle conversion member 52 is made of a compound parabolic concentrator (CPC). The angle conversion member 52 is made of a light-transmitting material such as borosilicate glass such as N-BK7, or a cycloolefin resin such as E-48R.

[0060] The angle conversion member 52 has an incident end face 52a on which the fluorescence Y emitted from the first surface 50a of the wavelength conversion member 50 is incident, an emission end face 52b from which the fluorescence Y incident from the incident end face 52a is emitted, and four side faces 52c in contact with each of the incident end face 52a and the emission end face 52b. Each of the four side faces 52c functions as a reflection surface that reflects the fluorescence Y incident from the incident end face 52a toward the emission end face 52b. Hereinafter, the side face 52c may also be referred to as the reflection surface 52c. The side face 52c and the reflection surface 52c in this embodiment correspond to the second side face of the claims.

[0061] The cross-sectional area of ​​the angle conversion member 52 perpendicular to the optical axis J gradually increases from the incident end face 52a toward the exit end face 52b. Therefore, the area of ​​the exit end face 52b is larger than the area of ​​the incident end face 52a. The width of each reflecting surface 52c in the direction perpendicular to the optical axis J gradually increases from the incident end face 52a toward the exit end face 52b. When the angle conversion member 52 is viewed from the direction perpendicular to the optical axis J (Z-axis direction), the shape of each reflecting surface is parabolic. The axis passing through the center of the exit end face 52b and the incident end face 52a and parallel to the X-axis is defined as the optical axis J of the angle conversion member 52. The optical axis J of the angle conversion member 52 coincides with the optical axis AX1 of the first lighting device 20.

[0062] 2, the fluorescence Y incident on the angle conversion member 52 changes direction each time it is totally reflected by the reflecting surface 52c while traveling inside the angle conversion member 52 so as to approach a direction parallel to the optical axis J. In this way, the angle conversion member 52 converts the emission angle distribution of the fluorescence Y emitted from the second surface 50b of the wavelength conversion member 50. Specifically, the angle conversion member 52 makes the maximum emission angle of the fluorescence Y at the emission end surface 52b smaller than the maximum incidence angle of the fluorescence Y at the incidence end surface 52a.

[0063] Generally, the etendue of light, which is defined as the product of the area of ​​the light emission region and the solid angle (maximum emission angle) of light, is preserved, and therefore the etendue of the fluorescence Y is preserved both before and after transmission through the angle conversion member 52. As described above, the angle conversion member 52 has a configuration in which the area of ​​the emission end face 52b is larger than the area of ​​the incidence end face 52a. Therefore, from the viewpoint of etendue preservation, the angle conversion member 52 can make the maximum emission angle of the fluorescence Y at the emission end face 52b smaller than the maximum incidence angle of the fluorescence Y incident on the incidence end face 52a.

[0064] 6, the first bonding layer 41 and the second bonding layer 42 bond the wavelength conversion member 50 and the angle conversion member 52. That is, the wavelength conversion member 50 and the angle conversion member 52 are bonded by the first bonding layer 41 and the second bonding layer 42.

[0065] The first bonding layer 41 is made of an adhesive and is provided between the first surface 50a of the wavelength conversion member 50 and the incident end surface 52a of the angle conversion member 52. It is preferable that the first bonding layer 41 is provided in the entire area between the first surface 50a and the incident end surface 52a. In this case, there is no gap (air layer) between the wavelength conversion member 50 and the angle conversion member 52. Note that the first bonding layer 41 only needs to be provided in at least a part of the area between the first surface 50a and the incident end surface 52a. The first bonding layer 41 has optical transparency. For example, a phenyl-based silicone resin adhesive having thermosetting or ultraviolet curing properties is used as the material of the first bonding layer 41.

[0066] If a gap is provided between the wavelength conversion member 50 and the angle conversion member 52, the fluorescence Y that reaches the first surface 50a of the wavelength conversion member 50 and is incident on the first surface 50a at an angle equal to or greater than the critical angle is totally reflected by the first surface 50a and cannot be incident on the angle conversion member 52. In contrast, as in the present embodiment, if the first bonding layer 41 is present in the entire region between the wavelength conversion member 50 and the angle conversion member 52 and no gap is present, the fluorescence Y that cannot be incident on the angle conversion member 52 can be reduced. From this perspective, it is desirable that the refractive index of the wavelength conversion member 50, the refractive index of the angle conversion member 52, and the first bonding layer 41 match as closely as possible.

[0067] However, in general, the wavelength conversion member 50 is made of a material containing a phosphor such as YAG, and the angle conversion member 52 is made of a light-transmitting material such as borosilicate glass, so that the wavelength conversion member 50 has a refractive index of about 1.8, and the angle conversion member 52 has a refractive index of about 1.50 to 1.55. Thus, it is difficult to match the refractive index of the wavelength conversion member 50 and the refractive index of the angle conversion member 52 with each other. Therefore, it is desirable to match at least the refractive index of the angle conversion member 52 with the refractive index of the first bonding layer 41 as much as possible. When borosilicate glass is used for the angle conversion member 52, the refractive index of the angle conversion member 52 is about 1.5, and by using a phenyl-based silicone resin as the adhesive for the first bonding layer 41 and appropriately adjusting, for example, additives, the refractive index of the first bonding layer 41 can be about 1.5, and the refractive indexes of both are approximately the same.

[0068] The second bonding layer 42 is made of an adhesive and is provided across the first bonding layer 41, covering a part of the side surface 50c of the wavelength conversion member 50 and a part of the reflecting surface 52c of the angle conversion member 52. In the case of the present embodiment, the second bonding layer 42 is provided across one side surface 50c and one reflecting surface 52c of the four side surfaces 50c, 50d, 50e, and 50f of the wavelength conversion member 50 and the four reflecting surfaces 52c of the angle conversion member 52.

[0069] The surface on which the second bonding layer 42 is provided may be any of the four side surfaces 50c, 50d, 50e, and 50f and the four reflecting surfaces 52c. In this embodiment, the surface is one side surface 50c and one reflecting surface 52c located on the opposite side to the support surface 54s of the support member 54. With this configuration, the second bonding layer 42 is less likely to interfere with the support member 54, and it is easy to ensure the bonding area. As the material for the second bonding layer 42, for example, a dimethyl-based silicone resin adhesive having thermosetting or ultraviolet curing properties is used. As the second bonding layer 42, a dimethyl-based silicone resin adhesive is used, and for example, by appropriately adjusting additives, etc., the refractive index of the second bonding layer 42 can be set to, for example, 1.4. The material for the second bonding layer 42 may be the same as the material for the first bonding layer 41.

[0070] The second bonding layer 42 desirably has light-transmitting properties. With this configuration, the fluorescence Y incident on the second bonding layer 42 is hardly absorbed, so that the loss of the fluorescence Y can be reduced and the temperature rise of the second bonding layer 42 can be suppressed. This makes it possible to suppress deformation and deterioration of the second bonding layer 42 due to heat.

[0071] In the present embodiment, the second bonding layer 42 is provided in contact with one side surface 50c of the wavelength conversion member 50 and one reflecting surface 52c of the angle conversion member 52, so there is a risk that the fluorescence Y incident on the angle conversion member 52 from the wavelength conversion member 50 may leak to the outside via the second bonding layer 42. This may reduce the extraction efficiency of the fluorescence Y emitted from the angle conversion member 52. In contrast, in the present embodiment, the second bonding layer 42 is provided only on one side surface 50c and one reflecting surface 52c out of the four side surfaces 50c, 50d, 50e, and 50f and the four reflecting surfaces 52c, so that the leakage of the fluorescence Y can be minimized.

[0072] The refractive index of the second bonding layer 42 is desirably lower than that of the wavelength conversion member 50, lower than that of the angle conversion member 52, and lower than that of the first bonding layer 41. With this configuration, total reflection is likely to occur at the interface between the wavelength conversion member 50 and the second bonding layer 42, the interface between the angle conversion member 52 and the second bonding layer 42, and the interface between the first bonding layer 41 and the second bonding layer 42, depending on the angle of incidence of the fluorescence Y at each interface. This can further suppress leakage of the fluorescence Y from the second bonding layer 42.

[0073] 2, a collimating optical system 63 including a collimator lens or the like is provided between the light source device 30 and the integrator optical system 31. The collimating optical system 63 further narrows the angular distribution of the fluorescence Y emitted from the angle conversion member 52, and causes the highly parallel fluorescence Y to be incident on the integrator optical system 31. Note that the collimating optical system 63 does not need to be provided when the parallelism of the fluorescence Y emitted from the angle conversion member 52 is sufficiently high.

[0074] The integrator optical system 31 has a first lens array 61 and a second lens array 62. The integrator optical system 31, together with the superimposing optical system 33, functions as a uniform illumination optical system that uniformizes the intensity distribution of the fluorescence Y emitted from the light source device 30 in each of the light modulation devices 4R and 4G, which are the illuminated areas. The fluorescence Y emitted from the collimating optical system 63 is incident on the first lens array 61. The first lens array 61, together with the second lens array 62, constitute the integrator optical system 31.

[0075] The first lens array 61 has a plurality of first lenses 61a. The plurality of first lenses 61a are arranged in a matrix in a plane parallel to the YZ plane perpendicular to the optical axis AX1 of the first illumination device 20. The plurality of first lenses 61a split the fluorescence Y emitted from the angle conversion member 52 into a plurality of partial light beams. The shape of each of the first lenses 61a is a rectangle that is approximately similar to the shape of the image forming areas of the light modulation devices 4R and 4G. As a result, each of the partial light beams emitted from the first lens array 61 is efficiently incident on the image forming areas of the light modulation devices 4R and 4G.

[0076] The fluorescence Y emitted from the first lens array 61 travels toward the second lens array 62. The second lens array 62 is disposed opposite to the first lens array 61. The second lens array 62 has a plurality of second lenses 62a corresponding to the plurality of first lenses 61a of the first lens array 61. The second lens array 62, together with the superimposing optical system 33, forms each of the images of the plurality of first lenses 61a of the first lens array 61 in the vicinity of the image forming areas of the light modulation devices 4R and 4G. The plurality of second lenses 62a are arranged in a matrix in a plane parallel to the YZ plane perpendicular to the optical axis AX1 of the first illumination device 20. The superimposing optical system 33 is composed of one convex lens.

[0077] In this embodiment, the first lenses 61a of the first lens array 61 and the second lenses 62a of the second lens array 62 have the same size, but may have different sizes. In this embodiment, the first lenses 61a of the first lens array 61 and the second lenses 62a of the second lens array 62 are arranged at positions where their optical axes coincide with each other, but may be arranged in an eccentric state with respect to each other.

[0078] The polarization conversion element 32 converts the polarization direction of the fluorescence Y emitted from the second lens array 62. Specifically, the polarization conversion element 32 converts each partial light beam of the fluorescence Y split by the first lens array 61 and emitted from the second lens array 62 into linearly polarized light.

[0079] The polarization conversion element 32 has a polarization separation layer (not shown), a reflection layer (not shown), and a phase difference plate (not shown). The polarization separation layer transmits one linearly polarized component of the polarization components contained in the fluorescence Y emitted from the light source device 30 as is, and reflects the other linearly polarized component in a direction perpendicular to the optical axis AX1. The reflection layer reflects the other linearly polarized component reflected by the polarization separation layer in a direction parallel to the optical axis AX1. The phase difference plate converts the other linearly polarized component reflected by the reflection layer into one linearly polarized component.

[0080] [Effects of the first embodiment] The light source device 30 of this embodiment includes a light emitting element 56 that emits excitation light E, a wavelength conversion member 50 that guides fluorescence Y generated from the excitation light emitted from the light emitting element 56, an angle conversion member 52 that converts the angular distribution of the fluorescence Y emitted from the wavelength conversion member 50, and a first bonding layer 41 and a second bonding layer 42 that bond the wavelength conversion member 50 and the angle conversion member 52. The wavelength conversion member 50 has a first surface 50a and a second surface 50b located opposite each other in the X-axis direction, and side surfaces 50c, 50d, 50e, and 50f that contact the first surface 50a and the second surface 50b, respectively. The fluorescence Y guided through the wavelength conversion member 50 is emitted from the first surface 50a, and the excitation light E emitted from the light emitting element 56 is incident on the wavelength conversion member 50 from the side surface 50c. The angle conversion member 52 has an incident end face 52a on which the fluorescence Y emitted from the wavelength conversion member 50 is incident, an exit end face 52b from which the fluorescence Y incident from the incident end face 52a exits, and a reflecting surface 52c in contact with each of the incident end face 52a and the exit end face 52b. The first bonding layer 41 is provided at least partially between the first surface 50a and the incident end face 52a, and the second bonding layer 42 is provided across the first bonding layer 41, covering at least a part of the side surface 50c and at least a part of the reflecting surface 52c.

[0081] In the conventional light source device, the end face of the light guide and the incident end face of the angle conversion member are joined with an adhesive, so that the joining area is small and there is a risk that the desired joining strength cannot be obtained. In contrast, in the light source device 30 of the present embodiment, the wavelength conversion member 50 and the angle conversion member 52 are joined with the first joining layer 41 and the second joining layer 42, the first joining layer 41 is provided between the first surface 50a and the incident end surface 52a, and the second joining layer 42 is provided across the first joining layer 41 and over a part of the side surface 50c and a part of the reflecting surface 52c. As a result, in the light source device 30 of the present embodiment, the joining area is larger than that of the conventional light source device, and the joining strength between the wavelength conversion member 50 and the angle conversion member 52 can be increased. In addition, even if the temperature of the first joining layer 41 increases and some deterioration occurs when the high light density fluorescence Y passes through the first joining layer 41, the joining between the wavelength conversion member 50 and the angle conversion member 52 is reinforced by the second joining layer 42. As a result, according to this embodiment, it is possible to prevent the angle conversion member 52 from peeling off from the wavelength conversion member 50, and to realize a light source device 30 that can stably obtain a desired light output.

[0082] The projector 1 of this embodiment is equipped with the light source device 30 of this embodiment, and therefore has excellent display quality.

[0083] [Second embodiment] A second embodiment of the present invention will now be described with reference to FIGS. The basic configurations of the projector and light source device of the second embodiment are similar to those of the first embodiment, and differ from the first embodiment in that a holding member is added, so a description of the basic configurations of the projector and light source device will be omitted. Fig. 7 is a perspective view showing a main part of a light source device according to a second embodiment, and Fig. 8 is a side cross-sectional view taken along line VIII-VIII in Fig. 7. 7 and 8, components common to those in the drawings used in the first embodiment are given the same reference numerals, and description thereof will be omitted.

[0084] The light source device of the present embodiment includes a wavelength conversion member 50, an angle conversion member 52, a holding member 45, a first bonding layer 41, and a second bonding layer 42. In addition to the above components, the light source device includes components such as a light source unit, a mirror, a support member, a position regulating member, and a pressing member (not shown).

[0085] As shown in Fig. 7 and Fig. 8, the holding member 45 is formed as an integral member and has a housing groove portion 451 that houses the wavelength conversion member 50 and the angle conversion member 52. Therefore, the holding member 45 holds the wavelength conversion member 50 and the angle conversion member 52 in a form surrounding three side surfaces 50d, 50e, 50f and three reflection surfaces 52c out of the four side surfaces 50c, 50d, 50e, 50f of the wavelength conversion member 50 and the four reflection surfaces 52c of the angle conversion member 52. Metals such as aluminum, iron, and stainless steel are used as the material of the holding member 45. The holding member 45 is supported by a support member (not shown) by any means such as a screw.

[0086] Holding member 45 has convex portions 452 that protrude toward wavelength conversion member 50 and angle conversion member 52. Convex portions 452 are provided on the bottom surface of storage groove portion 451 that faces wavelength conversion member 50 and angle conversion member 52. The multiple convex portions 452 shown in Fig. 8 may be one continuous annular convex portion, or multiple convex portions. However, in the case of multiple convex portions, it is preferable that these multiple convex portions are arranged substantially continuously to form a closed region as a whole.

[0087] As in the first embodiment, the first bonding layer 41 is provided between the first surface 50a of the wavelength conversion member 50 and the incident end surface 52a of the angle conversion member 52. The second bonding layer 42 is provided across the first bonding layer 41, from the side surface 50d of the wavelength conversion member 50 to the reflecting surface 52c of the angle conversion member 52. In the case of this embodiment, the second bonding layer 42 is provided in an area surrounded by the convex portion 452 among the area surrounded by the wavelength conversion member 50, the angle conversion member 52, and the holding member 45. When forming the second bonding layer 42, a liquid adhesive is applied to the area surrounded by the convex portion 452 of the holding member 45, and then cured. At this time, the adhesive is blocked by the convex portion 452, and is prevented from spreading more than necessary. This makes it possible to prevent the leakage of the fluorescence Y from the second bonding layer 42 from increasing.

[0088] The reflecting layer 47 is provided on at least the area of ​​the bottom surface of the accommodation groove 451 where the second bonding layer 42 is provided, that is, the area surrounded by the convex portion 452. The reflecting layer 47 is made of a metal film or a dielectric multilayer film formed on the surface of the holding member 45. Alternatively, instead of the metal film or the dielectric multilayer film, the surface of the holding member 45 may be mirror-finished to impart reflectivity. With this configuration, the fluorescence Y leaking from the second bonding layer 42 can be reflected by the reflecting layer 47 and returned to the wavelength conversion member 50 and the angle conversion member 52. This makes it possible to suppress leakage of the fluorescence Y from the second bonding layer 42. The reflecting layer 47 of this embodiment corresponds to the reflecting portion in the claims. The other configuration of the light source device is similar to that of the first embodiment.

[0089] [Effects of the second embodiment] In the light source device of this embodiment, the second bonding layer 42 can increase the bonding strength between the wavelength conversion member 50 and the angle conversion member 52 more than in the past, thereby suppressing peeling of the angle conversion member 52 from the wavelength conversion member 50, thereby achieving a light source device that can stably obtain the desired light output, thereby achieving the same effect as in the first embodiment.

[0090] Furthermore, in this embodiment, since the wavelength conversion member 50 and the angle conversion member 52 are held by the holding member 45, less adhesive is required to form the second bonding layer 42, which reduces leakage of fluorescence Y from the second bonding layer 42 and increases the efficiency of extracting fluorescence Y.

[0091] 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 spirit of the present invention. For example, in the light source device of the above embodiment, the second bonding layer is provided across one of the four side surfaces of the wavelength conversion member and one of the four reflective surfaces of the angle conversion member, but instead of this configuration, the second bonding layer may be provided across multiple side surfaces and multiple reflective surfaces as long as the leakage of fluorescence from the second bonding layer is within an acceptable range. With this configuration, the bonding strength between the wavelength conversion member and the angle conversion member can be further increased.

[0092] In the above embodiment, the first bonding layer is provided on the entire surface between the first surface and the incident end surface, and the first bonding layer and the second bonding layer are in contact with each other. However, for example, the first bonding layer may not be provided on the peripheral portion between the first surface and the incident end surface, and a small gap may be provided between the first bonding layer and the second bonding layer. Alternatively, the first bonding layer may be in contact with the second bonding layer in a state where the first bonding layer protrudes outward from between the first surface and the incident end surface. In the above second embodiment, a reflecting portion is provided to reflect the fluorescence leaking from the second bonding layer, but even in the first embodiment that does not have a holding member, a reflecting portion may be provided on any surface of the second bonding layer.

[0093] In the above embodiment, a CPC is used as the angle conversion member. However, instead of a CPC, a tapered rod in the shape of a truncated square pyramid with an exit end face having an area larger than that of an entrance end face may be used.

[0094] In the above embodiment, each wall surface of the groove of the support member has a portion perpendicular to the support surface and a portion inclined to the support surface, but the shape of the groove is not particularly limited, and for example, the entire wall surface of the groove may be perpendicular to the support surface. Also, the wall surface of the groove may be curved.

[0095] In the above embodiment, the present invention is applied to a light source device equipped with a wavelength conversion member, but instead of this configuration, the present invention may be applied to a light source device that propagates incident light without wavelength conversion, and then controls the angular distribution and emits the light. In this case, the wavelength conversion member in the above embodiment replaces the light guide member, and the light emitted from the light emitting element is emitted from the angle conversion member as light of the same wavelength band.

[0096] In addition, the specific description of the shape, number, arrangement, material, etc. of each component of the light source device and the projector is not limited to the above embodiment and can be changed as appropriate. In addition, in the above embodiment, an example in which the light source device according to the present invention is mounted on a projector using a liquid crystal panel is shown, but this is not limited to this. The light source device according to the present invention may be applied to a projector using a digital micromirror device as a light modulation device. In addition, the projector does not need to have multiple light modulation devices, and may have only one light modulation device.

[0097] In the above embodiment, the light source device of the present invention is applied to a projector, but the present invention is not limited to this. The light source device of the present invention can also be applied to lighting fixtures, automobile headlights, and the like.

[0098] [Summary of this disclosure] The following is a summary of this disclosure.

[0099] (Appendix 1) A light emitting element that emits light; a light guiding member that guides the light emitted from the light emitting element; an angle conversion member that converts an angular distribution of the light emitted from the light guiding member; a first bonding layer and a second bonding layer that bond the light guiding member and the angle conversion member; Equipped with The light guiding member is a first surface and a second surface located opposite to each other in a longitudinal direction of the light guide member; a first side surface in contact with each of the first surface and the second surface; having the light guided through the light guide member is emitted from the first surface, the light emitted from the light emitting element is incident on the light guiding member from the first side surface, The angle conversion member is an incident end surface on which the light emitted from the light guiding member is incident; an exit end surface from which the light incident from the entrance end surface exits; a second side surface in contact with each of the entrance end surface and the exit end surface; having the first bonding layer is provided at least partially between the first surface and the incident end surface, The second bonding layer is provided across the first bonding layer to span at least a portion of the first side surface and at least a portion of the second side surface.

[0100] According to the configuration of Appendix 1, in addition to the first bonding layer, the second bonding layer can increase the bonding strength between the light-guiding member and the angle conversion member, thereby preventing the angle conversion member from peeling off from the light-guiding member, and realizing a light source device that can stably obtain the desired light output.

[0101] (Appendix 2) 2. The light source device according to claim 1, wherein the second bonding layer is light-transmitting.

[0102] According to the configuration of Supplementary Note 2, since the light incident on the second bonding layer is hardly absorbed, the light loss can be reduced and the temperature rise of the second bonding layer can be suppressed, thereby suppressing the deformation and deterioration of the second bonding layer due to heat.

[0103] (Appendix 3) The light source device according to claim 1 or 2, wherein the refractive index of the second bonding layer is lower than the refractive index of the light-guiding member, lower than the refractive index of the angle conversion member, and lower than the refractive index of the first bonding layer.

[0104] According to the configuration of Supplementary Note 3, total reflection is likely to occur at the interface between the light guide member and the second bonding layer, the interface between the angle conversion member and the second bonding layer, and the interface between the first bonding layer and the second bonding layer, depending on the angle of incidence of light at each interface, which makes it possible to suppress leakage of light from the second bonding layer.

[0105] (Appendix 4) a holding member for holding the light guiding member and the angle conversion member, 4. The light source device according to claim 1, wherein the second bonding layer is provided in an area surrounded by the light-guiding member, the angle conversion member, and the holding member.

[0106] According to the configuration of Appendix 4, the light-guiding member and the angle conversion member are held by the holding member, so that less adhesive is required to form the second bonding layer, light leakage from the second bonding layer can be reduced, and the light extraction efficiency can be improved.

[0107] (Appendix 5) 5. The light source device according to claim 4, wherein a reflecting portion is provided in at least a region of the holding member where the second bonding layer is provided.

[0108] According to the configuration of Supplementary Note 5, the light leaking from the second bonding layer can be reflected by the reflecting portion and returned to the light guide member and the angle conversion member, thereby making it possible to suppress the leakage of light from the second bonding layer.

[0109] (Appendix 6) the holding member has a convex portion protruding toward the light guide member and the angle conversion member, The light source device according to claim 4 or 5, wherein the second bonding layer is provided in an area surrounded by the light-guiding member, the angle conversion member, and the holding member, the area being surrounded by the convex portion.

[0110] According to the configuration of Supplementary Note 6, the adhesive constituting the second bonding layer is blocked by the protruding portion and prevented from spreading more than necessary, thereby making it possible to prevent the leakage of light from the second bonding layer from increasing.

[0111] (Appendix 7) the light emitting element emits a first light having a first wavelength band; The light source device according to any one of claims 1 to 6, wherein the light-guiding member is a wavelength conversion member that includes a phosphor, converts the first light emitted from the light-emitting element into a second light having a second wavelength band different from the first wavelength band, and emits the second light.

[0112] According to the configuration of Supplementary Note 7, it is possible to realize a light source device capable of emitting the second light obtained by wavelength conversion of the first light.

[0113] (Appendix 8) A light source device according to any one of claims 1 to 7, a light modulation device that modulates the light emitted from the light source device in accordance with image information; a projection optical device that projects the light modulated by the light modulation device; A projector equipped with

[0114] According to the configuration of Supplementary Note 8, a projector capable of projecting an image with excellent display quality can be realized. [Explanation of symbols]

[0115] 1...projector, 4B, 4G, 4R...light modulation device, 6...projection optical device, 30...light source device, 41...first bonding layer, 42...second bonding layer, 45...holding member, 47...reflective layer (reflective portion), 50...wavelength conversion member (light guiding member), 50a...first surface, 50b...second surface, 50c, 50d, 50e, 50f...side surface (first side surface), 52...angle conversion member, 52a...incident end surface, 52b...exiting end surface, 52c...(reflective surface, second side surface), 56...light emitting element, 452...convex portion, E...excitation light (first light), Y...fluorescence (second light).

Claims

1. A light emitting element that emits light; a light guiding member that guides the light emitted from the light emitting element; an angle conversion member that converts an angular distribution of the light emitted from the light guiding member; a first bonding layer and a second bonding layer that bond the light guiding member and the angle conversion member; Equipped with The light guiding member is a first surface and a second surface located opposite to each other in a longitudinal direction of the light guide member; a first side surface in contact with each of the first surface and the second surface; having The light guided through the light guide member is emitted from the first surface, the light emitted from the light emitting element is incident on the light guiding member from the first side surface, The angle conversion member is an incident end surface on which the light emitted from the light guiding member is incident; an exit end surface from which the light incident from the entrance end surface exits; a second side surface contacting the entrance end surface and the exit end surface; having the first bonding layer is provided at least partially between the first surface and the incident end surface, The second bonding layer is provided across the first bonding layer and over at least a portion of the first side surface and at least a portion of the second side surface.

2. The light source device according to claim 1 , wherein the second bonding layer is light-transmitting.

3. 3 . The light source device according to claim 1 , wherein a refractive index of the second bonding layer is lower than a refractive index of the light guide member, a refractive index of the angle conversion member, and a refractive index of the first bonding layer.

4. a holding member for holding the light guiding member and the angle conversion member, 3 . The light source device according to claim 1 , wherein the second bonding layer is provided in a region surrounded by the light guide member, the angle conversion member, and the holding member.

5. The light source device according to claim 4 , wherein a reflecting portion is provided in at least a region of the holding member where the second bonding layer is provided.

6. the holding member has a protrusion protruding toward the light guide member and the angle conversion member, The light source device according to claim 4 , wherein the second bonding layer is provided in a region surrounded by the convex portion, out of a region surrounded by the light guide member, the angle conversion member, and the holding member.

7. the light-emitting element emits a first light having a first wavelength band; 3. The light source device according to claim 1, wherein the light-guiding member is a wavelength conversion member that contains a phosphor, converts the first light emitted from the light-emitting element into a second light having a second wavelength band different from the first wavelength band, and emits the second light.

8. The light source device according to claim 1 or 2, a light modulation device that modulates the light emitted from the light source device in accordance with image information; a projection optical device that projects the light modulated by the light modulation device; A projector equipped with

Images