Light source device

Abstract

To provide a light source device which has good light collecting performance.SOLUTION: A light source device 100 comprises: one or more optical members each having a plurality of light emitting parts 113 aligned along at least an alignment direction, a first reflection surface 21 and a second reflection surface 22, the optical members reflecting light from the plurality of light emitting parts 113 and emitting the light in a prescribed direction; and a condenser lens 4 for condensing the light emitted from the one or more optical members. The first reflection surface 21 reflects the light emitted from the plurality of light emitting parts 113 toward the second reflection surface 22, the second reflection surface 22 reflects the light reflected by the first reflection surface 21. The first reflection surface 21 and the second reflection surface 22 are faces having curvature radii in the alignment direction, where the curvature radius (1 / R2) of the second reflection surface 22 in the alignment direction is larger than the curvature radius (1 / R1) of the first reflection surface 21 in the alignment direction.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present disclosure relates to a light source device. [Background technology]

[0002] Conventionally, light source devices including semiconductor lasers or light-emitting diodes have been widely used. For example, Patent Document 1 discloses a configuration including one or more solid-state light sources that are arranged behind an emission section that can emit light in a predetermined wavelength range along an optical axis direction and that emit the light in the predetermined wavelength range along the same direction as the optical axis direction, and a focusing optical system that focuses the light in the predetermined wavelength range emitted from the one or more solid-state light sources onto a light emitter from behind the emission section. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] International Publication No. 2014 / 073152 Summary of the Invention [Problem to be solved by the invention]

[0004] Light source devices are required to have good light-collecting properties.

[0005] An object of an embodiment of the present disclosure is to provide a light source device with good light-collecting properties. [Means for solving the problem]

[0006] A light source device according to an embodiment of the present disclosure includes one or more optical elements having a plurality of light-emitting elements arranged at least along an arrangement direction, a first reflecting surface, and a second reflecting surface, which reflects light from the plurality of light-emitting elements and emits it in a predetermined direction, and a focusing lens which focuses the light emitted from the one or more optical elements, wherein the first reflecting surface reflects the light emitted by the plurality of light-emitting elements toward the second reflecting surface, and the second reflecting surface reflects the light reflected by the first reflecting surface, and each of the first reflecting surface and the second reflecting surface is a surface having a curvature in the arrangement direction, and the curvature of the second reflecting surface in the arrangement direction is greater than the curvature of the first reflecting surface in the arrangement direction. [Effects of the Invention]

[0007] According to the light source device according to the embodiment of the present disclosure, a light source device with good light-collecting properties can be provided. [Brief explanation of the drawings]

[0008] [Figure 1] 1 is a perspective view showing an example of the configuration of a light source device according to a first embodiment. [Figure 2] 1 is a perspective view of a housing capable of accommodating a light source device according to an embodiment, as viewed from the front side. [Figure 3] 1 is a perspective view of a housing capable of accommodating a light source device according to an embodiment, as viewed from the rear side. [Figure 4] FIG. 2 is a perspective view of an array light-emitting unit included in the light source device according to the embodiment. [Figure 5] 3A and 3B are top views of a configuration example of an array light-emitting unit included in the light source device according to the embodiment. [Figure 6] 6 is a cross-sectional view taken along the line VI-VI in FIG. 5. [Figure 7] 3 is a rear view of an example of the configuration of a parabolic mirror included in the light source device according to the first embodiment. FIG. [Figure 8] 3 is a top view of an example of the configuration of a parabolic mirror included in the light source device according to the first embodiment. FIG. [Figure 9] 2 is a perspective view of a parabolic mirror included in the light source device according to the first embodiment. FIG. [Figure 10] 3A and 3B are diagrams illustrating reflection by a parabolic mirror of the light source device according to the first embodiment. [Figure 11] 10 is a cross-sectional view taken along the line XI-XI in FIG. [Figure 12] FIG. 2 is a perspective view of a stepped mirror included in the light source device according to the embodiment. [Figure 13] 13 is a cross-sectional view taken along the line XIII-XIII in FIG. 12. [Figure 14] 10A and 10B are diagrams illustrating reflection of a laser beam by a stepped reflecting surface of a stepped mirror. [Figure 15] FIG. 2 is a perspective view of an end of a ferrule for illustrating an optical fiber. [Figure 16] 10A and 10B are diagrams illustrating an example of the configuration of an optical member group according to a first modified example of the first embodiment. [Figure 17] 10A and 10B are diagrams illustrating an example of the configuration of an optical member according to a second modified example of the first embodiment. [Figure 18] FIG. 10 is a perspective view of a parabolic mirror included in a light source device according to a second embodiment. [Figure 19] 10A and 10B are diagrams illustrating a first example of reflection by a parabolic mirror according to the second embodiment. [Figure 20] 10A and 10B are diagrams illustrating a second example of reflection by a parabolic mirror according to the second embodiment. [Figure 21] FIG. 10 is a perspective view of a first example of the configuration of a light source device according to a third embodiment. [Figure 22] FIG. 11 is a perspective view of a second example of the configuration of the light source device according to the third embodiment. DETAILED DESCRIPTION OF THE INVENTION

[0009] A light-emitting device according to an embodiment of the present invention will be described in detail with reference to the drawings. However, the following embodiments are merely examples of light source devices for embodying the technical concept of the present embodiment, and are not limited thereto. Furthermore, unless otherwise specified, the dimensions, materials, shapes, relative positions, etc. of the components described in the embodiments are merely illustrative examples and are not intended to limit the scope of the present invention. Note that the size, positional relationship, etc. of components shown in each drawing may be exaggerated for clarity. Furthermore, in the following description, the same names and symbols indicate the same or similar components, and detailed description will be omitted as appropriate.

[0010] In the drawings shown below, directions may be indicated by the X-axis, Y-axis, and Z-axis, and the X-direction along the X-axis indicates the arrangement direction in which a plurality of array light-emitting units of the light source device according to the embodiment are arranged. The Y-direction along the Y-axis indicates the orthogonal direction that is substantially orthogonal to the arrangement direction, and the Z-direction along the Z-axis indicates the direction that is orthogonal to both the arrangement direction and the orthogonal direction.

[0011] Furthermore, the direction in which the arrow points in the X direction is referred to as the +X direction, and the direction opposite to the +X direction is referred to as the -X direction. The direction in which the arrow points in the Y direction is referred to as the +Y direction, and the direction opposite to the +Y direction is referred to as the -Y direction. The direction in which the arrow points in the Z direction is referred to as the +Z direction, and the direction opposite to the +Z direction is referred to as the -Z direction. The +Y direction is referred to as the front side, the -Y direction is referred to as the back side, and the +Z direction is referred to as the top side. Furthermore, the term "planar view" in the embodiments refers to viewing an object from the Z direction. However, these do not limit the orientation of the light source device when in use, and the orientation of the light source device is arbitrary.

[0012] The "approximately" in the above "approximately orthogonal" does not require exact orthogonality, but means that a deviation from orthogonality that is generally considered to be an error is permitted. Similarly, the "approximately" in "approximately coincident" or "approximately collimated" shown in the following embodiments does not require exactness, but means that a deviation that is generally considered to be an error is permitted.

[0013] [First embodiment] <Light source device 100 configuration example> The overall configuration of a light source device 100 according to the first embodiment will be described with reference to Fig. 1 to Fig. 3. Fig. 1 is a diagram showing an example of the configuration of the light source device 100, and is a perspective view of the light source device 100 viewed from the rear side with a housing 101 covering the light source device 100 removed. Figs. 2 and 3 are diagrams showing the light source device 100 with the housing 101 attached, with Fig. 2 being a perspective view of the light source device 100 viewed from the front side and Fig. 3 being a perspective view of the light source device 100 viewed from the rear side.

[0014] 1, light source device 100 includes array light emitting unit 1a, array light emitting unit 1b, array light emitting unit 1c, array light emitting unit 1d, parabolic mirror 2, stepped mirror 3, and condensing lens 4. Light source device 100 reflects light emitted from array light emitting unit 1a, array light emitting unit 1b, array light emitting unit 1c, and array light emitting unit 1d by parabolic mirror 2 and stepped mirror 3, respectively, and condenses the light reflected by stepped mirror 3 and emitted by condensing lens 4 to enter the core of optical fiber 5.

[0015] Array light-emitting unit 1a, array light-emitting unit 1b, array light-emitting unit 1c, and array light-emitting unit 1d are arranged along the X direction and are each provided on the +Z direction surface of light-emitting unit mounting substrate 6. Since array light-emitting unit 1a, array light-emitting unit 1b, array light-emitting unit 1c, and array light-emitting unit 1d all have the same function, they will hereinafter be collectively referred to as array light-emitting unit 1 unless otherwise distinguished.

[0016] Each of array light-emitting unit 1a, array light-emitting unit 1b, array light-emitting unit 1c, and array light-emitting unit 1d has a plurality of light-emitting units lined up along the Y direction, and emits a plurality of laser beams lined up along the Y direction. The laser beams emitted by array light-emitting unit 1 are an example of light and laser light emitted by a light-emitting unit.

[0017] The light emitting section of the array light emitting section 1 is, for example, a semiconductor laser element, but is not limited to this and may be a light emitting element other than a semiconductor laser element, such as an LED (Light Emitting Diode).

[0018] In this embodiment, the laser beam refers to a bundle of laser beams that are converged together, and can also be called a laser beam bundle. Furthermore, since the light emitted by the light-emitting unit is not limited to laser beam, the light-emitting unit can also be said to emit a beam of rays that is a convergence of light rays.

[0019] The light-emitting unit mounting substrate 6 is a plate-like member that is substantially rectangular in plan view, and is a substrate equipped with wiring on which light-emitting elements and various electrical elements can be mounted. However, the shape of the light-emitting unit mounting substrate 6 is not limited to this. An electrical connector 610 and an electrical connector 620 are provided on the surface of the light-emitting unit mounting substrate 6 facing the +Z direction. A driving current or driving voltage for driving the light-emitting units of the array light-emitting unit 1 is supplied via the electrical connector 610 and the electrical connector 620, respectively. Note that, although the present embodiment illustrates a light-emitting unit mounting substrate 6 formed by joining two plate-like members along the X direction, the present invention is not limited to this. The light-emitting unit mounting substrate 6 may be formed of one plate-like member or three or more plate-like members.

[0020] The parabolic mirror 2 and the stepped mirror 3 have a first reflecting surface 21 and a second reflecting surface 22, and correspond to a plurality of optical members that reflect the laser beams from the plurality of light-emitting units included in the array light-emitting unit 1 and emit them in the +Y direction. The parabolic mirror 2 corresponds to a first optical member that integrally includes the first reflecting surface 21 and the second reflecting surface 22. The stepped mirror 3 corresponds to a second optical member that has a stepped reflecting surface.

[0021] In other words, in this embodiment, the multiple optical members are two optical members including the parabolic mirror 2 and the stepped mirror 3. The +Y direction in which the two optical members consisting of the parabolic mirror 2 and the stepped mirror 3 emit laser beams is an example of a predetermined direction.

[0022] The condenser lens 4 collects the laser beam incident from the stepped mirror 3 and makes it incident on the core of the optical fiber 5. The condenser lens 4 contains, as a material, glass or resin such as quartz or BK7 that is transparent to the wavelength of the laser beam emitted by the array light emitter 1. From the viewpoint of preventing damage due to light energy, the condenser lens 4 is preferably made of a glass material. In this embodiment, the condenser lens 4 is illustrated as a single lens, but the condenser lens 4 may include a lens group combining multiple lenses. Furthermore, the condenser lens 4 can be a spherical lens or an aspherical lens, and can also be a plano-convex lens, a meniscus lens, a biconvex lens, or a combination thereof.

[0023] The light source device 100 includes an optical fiber 5 connected to the light source device 100 via an optical connector 7. The optical connector 7 is attached to the end of the optical fiber 5 on the -Y direction side, and includes a ferrule 71 and a housing 72. With the end of the optical fiber 5 on the -Y direction side fixed to the ferrule 71, the optical fiber 5 is held by the housing 72. The optical fiber 5 is covered with a coating member 51 on a portion of the optical fiber 5 other than the portion where the optical connector 7 is attached. The coating member 51 protects the optical fiber 5 by preventing breakage or damage to the optical fiber 5, and preventing dust from adhering to the optical fiber 5.

[0024] The optical connector 7 is a component for mechanically coupling and aligning the core of the optical fiber 5 so that light can pass through. The optical connector 7 is, for example, an FC connector, an SC connector, an ST connector, an LC connector, or an MU connector. By connecting the optical fiber 5 to the light source device 100 via the optical connector 7, optical loss due to misalignment of the core in the optical fiber 5 can be suppressed.

[0025] In this embodiment, the light source device 100 is used in a state where it is housed inside a housing 101 as shown in Figures 2 and 3. Note that the light source device 100 does not necessarily have to be housed inside the housing 101 when in use, but it is preferable that it be used in a state where it is housed inside the housing 101 from the viewpoint of preventing dust from adhering to the array light-emitting unit 1, the parabolic mirror 2, the stepped mirror 3, the condenser lens 4, etc. Furthermore, the housing may be a part of the light source device 100.

[0026] Each of array light emitter 1a, array light emitter 1b, array light emitter 1c, and array light emitter 1d is mounted on the surface on the +Z direction side of light-emitting unit mounting substrate 6. Each of parabolic mirror 2, stepped mirror 3, and condensing lens 4 is held by a holding member, and is housed inside housing 101 in a state where it is fixed to light-emitting unit mounting substrate 6 via the holding member. Note that each of parabolic mirror 2, stepped mirror 3, and condensing lens 4 may be fixed to housing 101 via a holding member.

[0027] The housing 101 has a base member 101a, a cover member 101b, a cover member 101c, and a connecting member 103. The cover members 101b and 101c are each connected to the base member 101a with screw members 102. The light source device 100 is fixed to the surface of the base member 101a on the +Z direction side, and is housed inside the housing 101 so that its periphery is covered by the cover members 101b and 101c.

[0028] The connecting member 103 is used to connect the optical connector 7 to the light source device 100. The connecting member 103 includes a ferrule insertion hole 103a and a screw portion 103b, and is fixed by a screw member 104 to the +Y direction side of the cover member 101b.

[0029] The optical connector 7 is connected to the light source device 100 by inserting the ferrule 71 into the ferrule insertion hole 103a and coupling a screw portion provided on the housing 72 of the optical connector 7 with a screw portion 103b of the connection member 103.

[0030] The ferrule insertion hole 103a and the ferrule 71 are manufactured so that their central axes coincide with each other, and the core of the optical fiber 5 is positioned by inserting the ferrule 71 into the ferrule insertion hole 103a.

[0031] The condenser lens 4 in the light source device 100 is positioned so that the position of the core of the optical fiber 5 attached to the housing 101 via the optical connector 7 coincides with the position where the laser beam is condensed by the condenser lens 4. Therefore, the light source device 100 can condense the laser beams emitted by the plurality of array light-emitting units 1 with the condenser lens 4, thereby making the laser beams incident on the core of the optical fiber 5.

[0032] The laser beam that is incident on the core of the optical fiber 5 and guided through the optical fiber 5 is emitted from the end of the optical fiber 5 opposite to the end to which the optical connector 7 is attached, and is used for illumination purposes, etc. The light source device 100 is used in illumination, in-vehicle headlights, optical measuring instruments, optical processing instruments, various optical devices, etc. However, the uses of the light source device 100 are not limited to these uses.

[0033] <Configuration example of array light-emitting unit 1> 4 and 6 are diagrams illustrating the configuration of the array light-emitting unit 1. Fig. 4 is a perspective view of the array light-emitting unit 1. Fig. 5 is a top view showing an example of the configuration of the array light-emitting unit 1. Fig. 6 is a cross-sectional view taken along line VI-VI in Fig. 5 as viewed from the -Y direction side.

[0034] 4 to 6, the array light-emitting unit 1 includes a package 11, a light-transmitting member 12, and a lens array 13. The package 11 includes a bottom 111 and a sidewall 115. The package 11 includes four submounts 112, four light-emitting units 113, and four light-reflecting units 114.

[0035] A package 11 is mounted on the +Z direction surface of the light-emitting unit mounting substrate 6, a light-transmitting member 12 is arranged on the +Z direction side of the package 11, and a lens array 13 is arranged on the +Z direction side of the light-transmitting member 12.

[0036] Submount 112 is a collective term for submount 112a, submount 112b, submount 112c, and submount 112d. Light-emitting portion 113 is a collective term for light-emitting portion 113a, light-emitting portion 113b, light-emitting portion 113c, and light-emitting portion 113d. Light-reflecting portion 114 is a collective term for light-reflecting portion 114a, light-reflecting portion 114b, light-reflecting portion 114c, and light-reflecting portion 114d.

[0037] The light emitting portions 113 are arranged along the Y direction and are disposed on the +Z direction surface of the submount 112 which is disposed on the +Z direction surface of the bottom portion 111. Each of the four light emitting portions 113 emits a laser beam toward the light reflecting portion 114 which forms a pair with it.

[0038] The light-emitting unit 113 can be a laser beam with a peak emission wavelength in the visible light range of 380 nm to 780 nm. It can be a laser beam with a peak emission wavelength in the range of 420 nm to 495 nm, or a laser beam with a peak emission wavelength in the range of 495 nm to 570 nm or a laser beam with a peak emission wavelength in the range of 605 nm to 750 nm. It can also be a laser beam with a peak emission wavelength in the invisible light range, such as infrared or ultraviolet light. The light-emitting unit 113 is preferably made of a material containing, for example, a nitride semiconductor. Examples of nitride semiconductors include those containing at least one of GaN, InGaN, and AlGaN. The submount 112 can be made of, for example, aluminum nitride or silicon carbide.

[0039] The light reflecting portions 114 are arranged in the Y direction to form pairs with the light emitting portions 113, and are disposed on the upper surface of the bottom portion 111. The light reflecting portions 114 reflect the laser beam emitted by the light emitting portions 113 in the +Z direction. The light reflecting portions 114 can contain a glass material such as quartz or BK7 as a main material, a heat-resistant metal material such as aluminum, Si, etc., and the light-reflecting surface can be made of a material with high reflectivity such as a metal or a dielectric multilayer film.

[0040] The light-transmitting member 12 is provided between the package 11 and the lens array 13 and serves to seal the inside of the package 11. The light-transmitting member 12 may be made of, for example, quartz, a glass material such as BK7, or sapphire, which is light-transmitting to the wavelength of the laser beam emitted by the light-emitting unit 113.

[0041] Lens array 13 is a member in which four collimator lenses 131a, 131b, 131c, and 131d arranged along the Y direction are connected by connection portions 132. When collimator lenses 131a, 131b, 131c, and 131d are not distinguished from one another, they are collectively referred to as collimator lenses 131. Lens array 13 is made of, for example, a glass material such as BK7 that is translucent to the wavelength of the laser light emitted by light-emitting portion 113, and is manufactured by integral molding or the like.

[0042] The laser beam emitted by the light emitting section 113 and reflected in the +Z direction by the light reflecting section 114 passes through the light-transmitting member 12 and then enters the lens array 13 .

[0043] The four collimating lenses 131 in the lens array 13 are provided in pairs with the light-emitting units 113, and approximately collimate (approximately parallelize) the incident laser light and emit it toward the parabolic mirror 2 arranged on the +Z direction side of the array light-emitting unit 1. In this embodiment, an approximately collimated laser beam is emitted, but the laser beam emitted from the array light-emitting unit 1 is not limited to collimated light, and may be converging light or diverging light.

[0044] Each of the four array light-emitting units 1 has four light-emitting units 113, and the light source device 100 has a total of 16 light-emitting units 113 arranged along each of the X and Y directions. The light source device 100 can emit 16 laser beams.

[0045] However, the number of array light-emitting units 1 is not limited to four and can be selected appropriately depending on the application of light source device 100. Similarly, the number of light-emitting units 113 included in each array light-emitting unit 1 is not limited to four and can be selected appropriately depending on the application of light source device 100.

[0046] The light emitting sections 113 are not limited to those arranged in two axial directions, the X direction and the Y direction, but may be arranged in one axial direction, either the X direction or the Y direction. The number of submounts 112, light reflecting sections 114, and collimating lenses 131 can be selected appropriately according to the number of light emitting sections 113.

[0047] <Configuration and function example of parabolic mirror 2> 7 to 10 are diagrams illustrating the configuration and function of the parabolic mirror 2. FIGS. 7 and 8 are diagrams illustrating the light source device 100 with the housing 101 removed, with FIG. 7 being a rear view and FIG. 8 being a top view. FIG. 9 is a perspective view of the parabolic mirror 2. FIG. 10 is a diagram illustrating reflection by the parabolic mirror 2, and is a cross-sectional view of a portion of each of the first reflecting surface 21 and the second reflecting surface 22 of the parabolic mirror 2, viewed from the -Y direction.

[0048] As shown in FIG. 7, the parabolic mirror 2 has an entrance surface 20, a first reflecting surface 21, a second reflecting surface 22, and an exit surface .

[0049] The parabolic mirror 2 contains, as a material, for example, glass or resin such as quartz or BK7 that is translucent to the wavelength of the laser beam emitted by the light emitting unit 113. Since the parabolic mirror 2 guides and reflects the laser beam inside, it is preferable that the parabolic mirror 2 contains a glass material in order to prevent damage due to optical energy.

[0050] The incident surface 20 and the exit surface 23 are both flat surfaces. In the X direction, the second reflecting surface 22 is provided in a portion sandwiched between the two incident surfaces 20. In addition, the exit surface 23 is provided in a portion sandwiched between the two first reflecting surfaces 21.

[0051] Each of the first reflecting surface 21 and the second reflecting surface 22 is a part of a cylindrical surface that has a curvature in the X direction and almost no curvature in the Y direction. Here, "almost no curvature" refers to a range that includes the tolerance that would normally occur when the curvature is zero and when designed to be zero curvature. Each of the first reflecting surface 21 and the second reflecting surface 22 has a parabolic shape in the X direction.

[0052] The parabolic shape in the X direction refers to the parabolic shape of the cross section when the surface is cut by a plane parallel to the plane containing the X axis and the Z axis. This also applies to the spherical shape in the X direction or the aspherical shape in the X direction.

[0053] The first reflecting surface 21 and the second reflecting surface 22 are not limited to surfaces having a parabolic shape in the X direction, and may be surfaces having a spherical shape in the X direction, or surfaces having an aspherical shape other than a parabolic shape in the X direction. In a surface having an aspherical shape in the X direction, such as a parabolic shape, the curvature of the surface varies depending on the position in the X direction, and the curvature of such a surface refers to the curvature in a region near the central axis of the surface (paraxial curvature).

[0054] Each of the first reflecting surface 21 and the second reflecting surface 22 has a heat-resistant metal material such as aluminum on its surface, which reflects the incident laser beam. The metal material on the surface can be selected appropriately depending on the wavelength of the laser beam emitted by the light-emitting unit 113, etc. As an alternative to a metal material, a dielectric multilayer film may be provided on the surface. The metal material or dielectric multilayer film on the surface is preferably a material with high reflectivity. The reflectivity is preferably such that 70% or more of the incident laser beam is reflected, more preferably 80% or more of the incident laser beam, and even more preferably 90% or more of the incident laser beam.

[0055] The first reflecting surface 21 and the second reflecting surface 22 are not limited to a configuration in which a metal material is provided on the surface, and the incident laser beam may be totally reflected by the first reflecting surface 21 and the second reflecting surface 22. In this case, the first reflecting surface 21 and the second reflecting surface 22 are manufactured to satisfy the total reflection condition, and do not need to have a metal material on the surface.

[0056] First reflecting surface 21 includes two regions, one on the +X direction side and one on the −X direction side, located in the center in the X direction with exit surface 23 interposed therebetween. These two regions include paraboloidal shapes with the same curvature in the X direction.

[0057] In Fig. 7, each of the four array light-emitting units 1 arranged along the X direction emits a substantially collimated laser beam in the +Z direction. In Fig. 7, the laser beam 50a emitted by array light-emitting unit 1a, the laser beam 50b emitted by array light-emitting unit 1b, the laser beam 50c emitted by array light-emitting unit 1c, and the laser beam 50d emitted by array light-emitting unit 1d are represented by thick solid lines.

[0058] In addition, in Fig. 7, two thick solid lines represent a laser beam emitted from one array light-emitting unit 1. In Fig. 8, one thick solid line represents a laser beam emitted from one array light-emitting unit 1. Hereinafter, when there is no particular need to distinguish between laser beam 50a, laser beam 50b, laser beam 50c, and laser beam 50d, they will be collectively referred to as laser beam 50.

[0059] Each of the four array light-emitting units 1 emits four laser beams arranged in the Y direction. In one array light-emitting unit 1, the four laser beams arranged in the Y direction are guided by the parabolic mirror 2 and reflected in the same manner when viewed from the Y direction side.

[0060] Laser beam 50a passes through incident surface 20 and enters the interior of parabolic mirror 2, is guided inside parabolic mirror 2, and then reaches first reflecting surface 21. Having reached first reflecting surface 21, laser beam 50a is reflected by first reflecting surface 21 toward second reflecting surface 22, is guided inside parabolic mirror 2, and then reaches second reflecting surface 22. Having reached second reflecting surface 22, laser beam 50a is reflected by second reflecting surface 22 toward exit surface 23, is guided inside parabolic mirror 2, and then exits from exit surface 23. Laser beam 50a emitted from exit surface 23 is incident on stepped mirror 3.

[0061] Like the laser beam 50a, the laser beams 50b, 50c, and 50d are each reflected by the parabolic mirror 2, emitted therefrom, and then incident on the stepped mirror 3.

[0062] 7, the overall width Wx1 represents the overall width of the multiple laser beams 50 along the X direction at the position where they are incident on the first reflecting surface 21. The overall width Wx2 represents the overall width of the multiple laser beams 50 along the X direction at the position where they are reflected by the second reflecting surface 22. Here, the width of one laser beam is 1 / e with respect to the peak intensity value in the light intensity distribution of the laser beam at a position away from the output end surface. 2 The width of the part having the above strength.

[0063] 10, the curvature (1 / R2) of the second reflecting surface 22 in the X direction is larger than the curvature (1 / R1) of the first reflecting surface 21 in the X direction. The curvature (1 / R1) is the curvature of a region near the central axis C21, which is a paraxial region of the first reflecting surface 21. The curvature (1 / R2) is the curvature of a region near the central axis C22, which is a paraxial region of the second reflecting surface 22. Note that in FIG. 10, the central axes C21 and C22 overlap, so the same symbols are used for both axes.

[0064] The focal point F1 of the first reflecting surface 21 overlaps with the focal point F2 of the second reflecting surface 22. In other words, the focal point F1 and the focal point F2 are substantially coincident with each other. Here, "substantially coincident" means that the distance between the focal points F1 and F2 is within 0.05 mm.

[0065] A focal point is a point where reflected light converges when approximately collimated light is reflected. In Fig. 10, when collimated light emitted in the +Z direction from the array light-emitting unit is incident on first reflecting surface 21, the point where the collimated light converges after being reflected by first reflecting surface 21 is focal point F1 of first reflecting surface 21. When collimated light is incident on second reflecting surface 22 from the concave side of second reflecting surface 22, the point where the collimated light converges after being reflected by second reflecting surface 22 is focal point F2 of second reflecting surface 22.

[0066] In this embodiment, a configuration is exemplified in which the focal point F1 in the entire area of the first reflecting surface 21 excluding the exit surface 23 overlaps with the focal point F2 in the entire area of the second reflecting surface 22, but the present invention is not limited to this. A configuration in which the focal point F1 in at least a portion of the area of the first reflecting surface 21 overlaps with the focal point F2 in at least a portion of the area of the second reflecting surface 22 may also be used.

[0067] Since the first reflecting surface 21 and the second reflecting surface 22 each have a curvature in the X direction, the laser beam 50c reflected by the first reflecting surface 21 is focused in the X direction. Since the focal point F1 of the first reflecting surface 21 and the focal point F2 of the second reflecting surface 22 substantially coincide with each other, the laser beam 50c reflected by the first reflecting surface 21 and then by the second reflecting surface 22 is substantially collimated again.

[0068] The first reflecting surface 21 and the second reflecting surface 22 constitute an afocal optical system in which collimated light is incident and collimated light is emitted. The curvature (1 / R2) of the second reflecting surface 22 is larger than the curvature (1 / R1) of the first reflecting surface 21. Therefore, the beam width D2 along the X direction of the laser beam 50c at the position reflected by the second reflecting surface 22 is narrower than the beam width D1 along the X direction of the laser beam 50c at the position incident on the first reflecting surface 21.

[0069] In other words, the beam width of the laser beam 50 emitted by the light-emitting unit 113 along the X direction is such that the beam width D2 at the position where the laser beam 50 is reflected by the second reflecting surface 22 is narrower than the beam width D1 at the position where the laser beam 50 is incident on the first reflecting surface 21. Specifically, the beam width D2 is approximately equal to the beam width obtained by multiplying the beam width D1 by the ratio (R2 / R1) of the curvature (1 / R2) to the curvature (1 / R1). Also, as shown in FIG. 7, the overall width Wx2 is narrower than the overall width Wx1. The ratio between the beam width D1 and the beam width D2 and the ratio between the overall width Wx1 and the overall width Wx2 can be changed as appropriate depending on the number of light-emitting units, the core diameter of the optical fiber 5, etc.

[0070] In this embodiment, the laser beam 50c incident on the first reflecting surface 21 is approximately collimated, and therefore the beam width D1 of the laser beam 50c is approximately constant regardless of the position on the optical path from when it leaves the lens array 13 of the array light emitter 1 until it is incident on the first reflecting surface 21. Similarly, the laser beam 50c reflected by the second reflecting surface 22 is also approximately collimated, and therefore the beam width D2 of the laser beam 50c is approximately constant regardless of the position on the optical path from when it is reflected by the second reflecting surface 22 until it is incident on the stepped mirror 3.

[0071] Since the first reflecting surface 21 has a parabolic shape in the X direction, the reflected laser beam 50c can be focused to the focal point F1 while suppressing spherical aberration in the X direction. Furthermore, since the second reflecting surface 22 has a parabolic shape in the X direction, the reflected laser beam 50c can be approximately collimated while suppressing spherical aberration in the X direction.

[0072] On the other hand, since the first reflecting surface 21 and the second reflecting surface 22 have almost no curvature in the Y direction, the laser beam 50c from the array light-emitting unit 1 is reflected by the first reflecting surface 21 and the second reflecting surface 22 while remaining in an approximately collimated state, and is emitted toward the step mirror 3.

[0073] Here, the laser beam 50c has been described as an example, but the same applies to the other laser beams 50a, 50b, and 50d.

[0074] In this embodiment, the array light-emitting unit 1 emits collimated light, and the light reflected by the second reflecting surface 22 becomes collimated light, but this does not necessarily have to be collimated light, and may be converging light or diverging light.

[0075] <Example of the structure and function of the step mirror 3> 11 to 14 are diagrams illustrating the configuration and function of the stepped mirror 3. FIG. 11 is a cross-sectional view taken along line XI-XI in FIG. 7 as viewed from the -X direction. FIG. 12 is a perspective view of the stepped mirror 3 as viewed from the +Y direction. FIG. 13 is a cross-sectional view taken along line XIII-XIII in FIG. 12 as viewed from the -X direction. FIG. 14 is a diagram illustrating reflection of a laser beam by the stepped reflecting surface of the stepped mirror 3. FIG. 14 shows the stepped mirror 3 tilted at 45 degrees around the X axis with respect to a plane including the X and Z axes as viewed from the +Y direction.

[0076] 11, thick solid lines represent laser beams 50a, 50b, 50c, and 50d emitted by the plurality of array light-emitting units 1. Also, in FIG. 11, a laser beam emitted from one array light-emitting unit 1 is represented by a single thick solid line.

[0077] 11, the stepped mirror 3 is disposed on the +Z direction side of the parabolic mirror 2, tilted at approximately 45 degrees around the X axis with respect to a plane including both the X axis and the Z axis. However, this angle is not limited to approximately 45 degrees and can be selected appropriately depending on the position where the optical fiber 5 is disposed, etc.

[0078] The stepped mirror 3 reflects the laser beam 50ba, the laser beam 50bb, the laser beam 50bc, and the laser beam 50bd emitted in the +Z direction from the exit surface 23 of the parabolic mirror 2, toward the condenser lens 4. The laser beam 50ba, the laser beam 50bb, the laser beam 50bc, and the laser beam 50bd reflected by the stepped mirror 3 are incident on the condenser lens 4, and are condensed by the condenser lens 4 to enter the core of the optical fiber 5 held in the optical connector 7.

[0079] 12 and 13, the stepped mirror 3 is a mirror on which a stepped reflecting surface 32 having a plurality of stepped surfaces of different heights is formed. The stepped reflecting surface 32 reflects the laser beam 50 reflected by the second reflecting surface 22 toward the focusing lens 4.

[0080] In this embodiment, the stepped reflecting surface 32 is formed by forming a plurality of recesses in the flat surface 31 of the plate-like member, the recesses having different heights (depths) relative to the flat surface 31, and providing a reflecting surface made of a metal material such as aluminum or a dielectric multilayer film on the flat surface 31 and the bottom of the recesses. The main material of the stepped mirror 3 contains, for example, glass such as quartz or BK7, or a resin. Since the stepped mirror 3 reflects the laser beam, it is preferable that it contains a glass material in order to prevent damage from optical energy, and the reflecting surface is preferably made of a heat-resistant material.

[0081] In this embodiment, the stepped reflecting surface 32 includes a first step surface 32a, a second step surface 32b, a third step surface 32c, and a fourth step surface 32d, which are arranged from the side closer to the parabolic mirror 2 to the side farther from the parabolic mirror 2. The first step surface 32a, the second step surface 32b, the third step surface 32c, and the fourth step surface 32d correspond to a plurality of step surfaces with different heights. With respect to the height relative to the flat surface 31, the first step surface 32a has a height ha, the second step surface 32b has a height hb, and the third step surface 32c has a height hc, and the fourth step surface 32d has no difference in height relative to the flat surface 31.

[0082] In FIG. 11, laser beam 50ba, laser beam 50bb, laser beam 50bc, and laser beam 50bd are four laser beams aligned in the Y direction. Laser beam 50ba is a laser beam emitted from collimator lens 131a of array light emitter 1b. Laser beam 50bb is a laser beam emitted from collimator lens 131b of array light emitter 1b. Laser beam 50bc is a laser beam emitted from collimator lens 131c of array light emitter 1b. Laser beam 50bd is a laser beam emitted from collimator lens 131d of array light emitter 1b.

[0083] When there is no need to distinguish between the laser beam 50ba, the laser beam 50bb, the laser beam 50bc, and the laser beam 50bd, they will be collectively referred to as the laser beam 50b. In Fig. 11, the laser beam 50b emitted by the array light-emitting unit 1b is shown as an example, but the other laser beams 50a, 50c, and 50d also behave in the same way when reflected by the stepped mirror 3 and collected by the collecting lens 4.

[0084] As shown in FIG. 14, the step reflecting surface 32 of the step mirror 3 includes a first step surface 32a, a second step surface 32b, a third step surface 32c, and a fourth step surface 32d, and reflects 16 laser beams 50.

[0085] The first step surface 32a, the second step surface 32b, the third step surface 32c, and the fourth step surface 32d respectively reflect the first light column 51a, the second light column 51b, the third light column 51c, and the fourth light column 51d in pairs. Specifically, the first step surface 32a reflects the first light column 51a in the +Y direction. The second step surface 32b reflects the second light column 51b in the +Y direction. The third step surface 32c reflects the third light column 51c in the +Y direction. The fourth step surface 32d reflects the fourth light column 51d in the +Y direction. The first light column 51a, the second light column 51b, the third light column 51c, and the fourth light column 51d each correspond to a plurality of light columns lined up along the Y direction.

[0086] 14, the first light column 51a, the second light column 51b, the third light column 51c, and the fourth light column 51d appear to be aligned only in the Z direction, but the first step surface 32a, the second step surface 32b, the third step surface 32c, and the fourth step surface 32d are located at different positions in the Y direction. Therefore, the first light column 51a, the second light column 51b, the third light column 51c, and the fourth light column 51d are also aligned in the Y direction.

[0087] The first light array 51a, the second light array 51b, the third light array 51c, and the fourth light array 51d each include a plurality of laser beams 50 that are reflected by the second reflecting surface 22 and aligned along the X direction. Specifically, the first light array 51a includes laser beams 50aa, 50ba, 50ca, and 50da aligned along the X direction. The second light array 51b includes laser beams 50ab, 50bb, 50cb, and 50db aligned along the X direction. The third light array 51c includes laser beams 50ac, 50bc, 50cc, and 50dc aligned along the X direction. The fourth light array 51d includes laser beams 50ad, 50bd, 50cd, and 50dd aligned along the X direction.

[0088] 13, the first step surface 32a, the second step surface 32b, the third step surface 32c, and the fourth step surface 32d differ in the height of the reflecting surface relative to the flat surface 31. Depending on the difference in height relative to the flat surface 31, the position along the Z direction of the laser beam 50 incident on each step surface from the parabolic mirror 2 shifts.

[0089] For example, when the laser beam 50 is reflected by the first step surface 32a, the incident position is shifted in the +Z direction depending on the height ha compared to when the laser beam 50 is reflected at the height of the flat portion 31. Similarly, when the laser beam 50 is reflected by the second step surface 32b, the incident position is shifted in the +Z direction depending on the height hb compared to when the laser beam 50 is reflected at the height of the flat portion 31. When the laser beam 50 is reflected by the third step surface 32c, the incident position is shifted in the +Z direction depending on the height hc compared to when the laser beam 50 is reflected at the height of the flat portion 31.

[0090] As a result, with regard to the spacing between the multiple laser beams 50, the spacing d2 in the Z direction at the position where the laser beam 50 is reflected by the step reflecting surface 32 is narrower than the spacing d1 in the Y direction at the position where the laser beam 50 is incident on the step reflecting surface 32. Also, the overall width Wy2 in the Z direction of the multiple laser beams 50 at the position where the laser beam 50 is reflected by the step reflecting surface 32 is narrower than the overall width Wy1 in the Y direction of the multiple laser beams 50 at the position where the laser beam 50 is incident on the step reflecting surface 32. The ratio between the spacing d1 and the spacing d2 and the ratio between the overall width Wy1 and the overall width Wy2 can be changed as appropriate depending on the number of light-emitting units, the core diameter of the optical fiber 5, etc.

[0091] <Configuration example of optical fiber 5> Fig. 15 is a perspective view of an end portion of a ferrule 71 for explaining an optical fiber 5. As shown in Fig. 15, the optical fiber 5 includes a core 52 and a cladding 53 that covers the periphery of the core 52. The ferrule 71 covers the optical fiber 5 via a coating 711 that covers the periphery of the cladding 53, and fixes the optical fiber 5 inside.

[0092] The laser beam 50 condensed by the condenser lens 4 is incident on the core 52 of the optical fiber 5. The light source device 100 may have a configuration that does not include the optical fiber 5 connected to the light source device 100.

[0093] <Effects of the Light Source Device 100> Next, the effects of the light source device 100 will be described.

[0094] In this embodiment, light source device 100 has a plurality of light-emitting units 113 arranged at least along the X direction (arrangement direction). Light source device 100 also has a first reflecting surface 21 and a second reflecting surface 22, and includes a parabolic mirror 2 and a stepped mirror 3 (a plurality of optical members) that reflect laser beams 50 (light) from the plurality of light-emitting units 113 and emit them in the +Y direction (a predetermined direction). Light source device 100 also includes a condenser lens 4 that condenses laser beams 50 emitted from parabolic mirror 2 and stepped mirror 3.

[0095] First reflecting surface 21 reflects laser beams 50 emitted from the plurality of light-emitting units 113 toward second reflecting surface 22, and second reflecting surface 22 reflects laser beams 50 reflected by first reflecting surface 21. First reflecting surface 21 and second reflecting surface 22 each have a curvature in the X direction, and the curvature of second reflecting surface 22 in the X direction (1 / R2) is larger than the curvature of first reflecting surface 21 in the X direction (1 / R1).

[0096] The light source device 100 collects light emitted from a plurality of light-emitting elements 113 using the collecting lens 4, and can collect a large amount of light.

[0097] The light source device 100 can collect a large amount of light because the overall width Wx1 of the multiple laser beams 50 along the X-direction at the position where the multiple laser beams 50 are incident on the first reflecting surface 21 can be increased in accordance with the number of multiple light-emitting sections 113 arranged along the X-axis direction.

[0098] Light source device 100 can make the overall width Wx2 of the multiple laser beams 50 along the X direction narrower than the above-mentioned overall width Wx1 at the position where the multiple laser beams 50 are reflected by second reflecting surface 22. This allows laser beam 50 having the overall width Wx2 to be focused in a narrow range using focusing lens 4 with a narrow aperture diameter and small aberration.

[0099] As described above, this embodiment can provide a light source device 100 with good light collection. The laser beam 50 can be efficiently incident on the core 52 of the optical fiber 5, and the brightness of the light emitted from the optical fiber can be increased, making it possible to use the light source device 100 for high-brightness lighting, etc.

[0100] The light source device 100 can use a condenser lens 4 with a narrow aperture diameter, and does not require a condenser lens made up of a combination of multiple lenses or a condenser lens with a complex shape, thereby reducing the cost of the light source device 100.

[0101] Furthermore, in this embodiment, the focal point F1 in at least a partial region of the first reflecting surface 21 overlaps with the focal point F2 in at least a partial region of the second reflecting surface 22. With this configuration, collimated light incident on the first reflecting surface 21 can be reflected by both the first reflecting surface 21 and the second reflecting surface 22, converted back into collimated light, and then incident on the focusing lens 4. Collimated light is more likely to pass through the intended optical path, so light loss such as flare or ghost light can be reduced compared to converging or diverging light. As a result, the light source device 100 can provide a light source device 100 with good focusing properties.

[0102] In this embodiment, the plurality of light-emitting sections 113 are arranged along the X and Y directions. The stepped mirror 3 includes a stepped reflecting surface 32 having a first step surface 32a, a second step surface 32b, a third step surface 32c, and a fourth step surface 32d that are different in height, and that reflects the laser beam 50 reflected by the second reflecting surface 22 toward the condenser lens 4.

[0103] The first step surface 32a, the second step surface 32b, the third step surface 32c, and the fourth step surface 32d respectively reflect, in pairs, the first light column 51a, the second light column 51b, the third light column 51c, and the fourth light column 51d, which are aligned along the Y direction. The first light column 51a, the second light column 51b, the third light column 51c, and the fourth light column 51d are each reflected by the second reflecting surface 22 and include a plurality of laser beams 50 aligned along the X direction. With this configuration, the light source device 100 can shift, in the Z direction, the positions at which the laser beams 50 are incident on the first step surface 32a, the second step surface 32b, the third step surface 32c, and the fourth step surface 32d. As a result, in the light source device 100, the overall width Wy1 along the Y direction of the multiple laser beams 50 can be increased in accordance with the number of multiple light-emitting units 113 arranged along the Y-axis direction at the position where the laser beams 50 are incident on the stepped reflecting surface 32, and more light can be collected. As described above, in this embodiment, a light source device 100 with good light collecting properties can be provided.

[0104] Furthermore, in this embodiment, the plurality of light-emitting units 113 each emit a laser beam 50, and the beam width (width) of the laser beam 50 along the X direction is such that the beam width D2 at the position where the laser beam 50 is reflected by the second reflecting surface 22 is narrower than the beam width D1 at the position where the laser beam 50 is incident on the first reflecting surface 21. Furthermore, the intervals between the plurality of laser beams 50 along the Z direction at the position where the laser beam 50 is reflected by the stepped reflecting surface 32 are narrower than the interval d1 along the Y direction at the position where the laser beam 50 is incident on the stepped reflecting surface 32. With this configuration, the light source device 100 can make the overall width Wx2 at the position where the laser beam 50 is reflected by the second reflecting surface 22 narrower than the overall width Wx1 at the position where the laser beam 50 is incident on the first reflecting surface 21. Furthermore, the light source device 100 can make the overall width Wy2 at the position where the laser beam 50 is reflected by the stepped reflecting surface 32 narrower than the overall width Wy1 at the position where the laser beam 50 is incident on the stepped reflecting surface 32.

[0105] Furthermore, in this embodiment, light source device 100 includes parabolic mirror 2 (first optical member) having first reflecting surface 21 and second reflecting surface 22 integrally therewith, and stepped mirror 3 (second optical member) having stepped reflecting surface 32. With this configuration, the first optical member and second optical member can be manufactured more easily than when using an optical member in which first reflecting surface 21, second reflecting surface 22, and stepped reflecting surface 32 are integrally configured. Furthermore, light source device 100 can be assembled more easily than when using an optical member in which first reflecting surface 21, second reflecting surface 22, and stepped reflecting surface 32 are each configured separately.

[0106] Furthermore, the light source device 100 may further include an optical fiber 5 including a core 52 and a cladding 53 surrounding the core 52, and the laser beam 50 focused by the focusing lens 4 may be incident on the core 52 of the optical fiber 5. Since light from a plurality of light-emitting units 113 can be guided by a single optical fiber 5, it is possible to provide a light source device that increases the efficiency of light incident on the core 52 of the optical fiber 5 while suppressing an increase in cost according to the number of optical fibers.

[0107] <Modification> In the first embodiment, an optical member made up of a parabolic mirror 2 and a stepped mirror 3 is exemplified, but the configuration of the optical member is not limited to this and various modifications are possible. Below, light source devices according to modifications having optical members with various configurations will be described. Note that the same names and symbols as in the first embodiment indicate the same or similar components, and detailed descriptions will be omitted as appropriate. This also applies to the other embodiments and modifications described below.

[0108] Fig. 16 is a diagram showing an example of the configuration of an optical member group 60a included in a light source device 100a according to a first modified example of Embodiment 1. As shown in Fig. 16, the optical member group 60a includes a first parabolic member 61, a second parabolic member 62, and a third parabolic member 63.

[0109] The first parabolic member 61 has a third reflecting surface 611 that is part of a cylindrical concave surface that has a curvature in the X direction. The second parabolic member 62 has a fourth reflecting surface 621 that is part of a cylindrical concave surface that has a curvature in the X direction. The third reflecting surface 611 and the fourth reflecting surface 621 include parabolic shapes that have the same curvature in the X direction. The third reflecting surface 611 and the fourth reflecting surface 621 are examples of first reflecting surfaces. The third reflecting surface 611 and the fourth reflecting surface 621 have the same function as the first reflecting surface 21 in the first embodiment.

[0110] The third parabolic member 63 has a fifth reflecting surface 631 that is part of a cylindrical convex surface that has a curvature in the X direction. The fifth reflecting surface 631 has a parabolic shape in the X direction. The fifth reflecting surface 631 is an example of a second reflecting surface. The fifth reflecting surface 631 has a function similar to that of the second reflecting surface 22 in the first embodiment.

[0111] The light source device 100a has an optical member group 60a including a first parabolic member 61 having a third reflecting surface 611, a second parabolic member 62 having a fourth reflecting surface 621, and a third parabolic member 63 having a fifth reflecting surface 631, and the members having reflecting surfaces corresponding to the first and second reflecting surfaces in the first embodiment are not integrally formed into a single member. Therefore, compared to the light source device 100 according to the first embodiment, it is possible to more easily manufacture the optical members having the first and second reflecting surfaces. Other effects are the same as those of the first embodiment.

[0112] 17 is a diagram showing an example of the configuration of an optical member 60b included in a light source device 100b according to a second modified example of Embodiment 1. As shown in Fig. 17, the optical member 60b has a sixth reflecting surface 641, a seventh reflecting surface 642, an eighth reflecting surface 643, and a first stepped reflecting surface 644.

[0113] The sixth reflecting surface 641 is a part of a cylindrical surface having a curvature in the X direction. The seventh reflecting surface 642 is a part of a cylindrical surface having a curvature in the X direction. The sixth reflecting surface 641 and the seventh reflecting surface 642 include paraboloidal shapes having the same curvature in the X direction. The sixth reflecting surface 641 and the seventh reflecting surface 642 are examples of first reflecting surfaces. The sixth reflecting surface 641 and the seventh reflecting surface 642 have the same function as the first reflecting surface 21 in the first embodiment.

[0114] The eighth reflecting surface 643 is a part of a cylindrical surface having a curvature in the X direction. The eighth reflecting surface 643 has a parabolic shape in the X direction. The eighth reflecting surface 643 is an example of a second reflecting surface. The eighth reflecting surface 643 has a function similar to that of the second reflecting surface 22 in the first embodiment.

[0115] The first step reflecting surface 644 has a plurality of step surfaces of different heights, and is an example of a step reflecting surface that reflects the laser beam reflected by the eighth reflecting surface 643 toward the collecting lens 4. The first step reflecting surface 644 has a function similar to that of the step reflecting surface 32 in the first embodiment.

[0116] The light source device 100b has an optical member 60b in which reflective surfaces corresponding to the first reflective surface, the second reflective surface, and the stepped reflective surface in the first embodiment are integrally formed in a single member. Therefore, assembly of the light source device 100b is easier than that of the light source device 100 according to the first embodiment. Other effects are the same as those of the first embodiment.

[0117] [Second embodiment] Next, a light source device 100c according to a second embodiment will be described. Fig. 18 is a perspective view showing an example of the configuration of a parabolic mirror 2c included in the light source device 100c. Fig. 18 shows the parabolic mirror 2c, array light emitter 1c, and array light emitter 1d of the light source device 100c.

[0118] 18 also shows light-emitting section 113ca, light-reflecting section 114ca, and collimating lens 131ca of array light-emitting section 1c, and light-emitting section 113da, light-reflecting section 114da, and collimating lens 131da of array light-emitting section 1d. Light-emitting section 113ca is an example of a first light-emitting section, and light-emitting section 113da is an example of a second light-emitting section.

[0119] The parabolic mirror 2c has a first reflecting surface 21c and a second reflecting surface 22c. The first reflecting surface 21c includes a first region 21ac and a second region 21bc. The second reflecting surface 22c includes a third region 22ac and a fourth region 22bc.

[0120] The first region 21ac reflects the laser beam 50c emitted by the light-emitting unit 113ca. The second region 21bc reflects the laser beam 50d emitted by the light-emitting unit 113da. The first region 21ac and the second region 21bc are each rectangular in plan view and have a surface that has curvature in the X direction and almost no curvature in the Y direction. The first region 21ac and the second region 21bc each have a parabolic shape in the X direction, but the parabolic shape of the first region 21ac is different from the parabolic shape of the second region 21bc.

[0121] The third region 22ac reflects the laser beam 50c emitted by the light-emitting unit 113ca and reflected by the first reflecting surface 21c. The fourth region 22bc reflects the laser beam 50d emitted by the light-emitting unit 113da and reflected by the first reflecting surface 21c. The third region 22ac and the fourth region 22bc are each rectangular in plan view and have a surface that has curvature in the X direction and almost no curvature in the Y direction. The third region 22ac and the fourth region 22bc each have a parabolic shape in the X direction, but the parabolic shape of the third region 22ac is different from the parabolic shape of the fourth region 22bc.

[0122] Laser beam 50c emitted in the −X direction by light-emitting unit 113ca is reflected in the +Z direction by light-reflecting unit 114ca, is approximately collimated by collimating lens 131ca, and then enters parabolic mirror 2c through incident surface 20. Laser beam 50c that entered parabolic mirror 2c is reflected by first region 21ac toward third region 22ac, and then reflected by third region 22ac toward exit surface 23, and is then emitted through exit surface 23.

[0123] Laser beam 50d emitted in the +X direction by light-emitting unit 113ca is reflected in the +Z direction by light-reflecting unit 114da, is approximately collimated by collimating lens 131da, and then enters parabolic mirror 2c through incident surface 20. Laser beam 50d that entered parabolic mirror 2c is reflected by second region 21bc toward fourth region 22bc, and then reflected by fourth region 22bc toward exit surface 23, and is then emitted through exit surface 23.

[0124] Figure 19 is a diagram illustrating a first example of reflection by a parabolic mirror according to the second embodiment, and is a cross-sectional view of a portion of each of the first reflecting surface 21c and the second reflecting surface 22c of the parabolic mirror 2c, viewed from the -Y direction.

[0125] The focal point Fc1 of the first region 21ac overlaps with the focal point Fc3 of the third region 22ac. In other words, the focal points Fc1 and Fc3 are substantially coincident. Therefore, the laser beam 50c reflected by the first region 21ac toward the third region 22ac is substantially collimated by reflection from the third region 22ac, and then exits through the exit surface 23.

[0126] The focal point Fc2 of the second region 21bc overlaps with the focal point Fc4 of the fourth region 22bc. In other words, the focal points Fc2 and Fc4 approximately coincide with each other. Therefore, the laser beam 50d reflected by the second region 21bc toward the fourth region 22bc is approximately collimated by reflection from the fourth region 22bc, and then exits through the exit surface 23. Note that, because the surface shape of the first region 21ac is different from that of the second region 21bc, the focal point Fc1 of the first region 21ac and the focal point Fc2 of the second region 21bc do not overlap.

[0127] In this embodiment, the first reflecting surface 21c is divided into two regions, a first region 21ac and a second region 21bc, each with a different focal point. Similarly, the second reflecting surface 22c is divided into two regions, a third region 22ac and a fourth region 22bc, each with a different focal point. This configuration allows the laser beam reflected by the second reflecting surface 22c to be focused. As a result, a light source device 100c with good focusing properties can be provided.

[0128] Furthermore, laser beam 50c from array light-emitting unit 1c is reflected by first region 21ac, then reflected by third region 22ac, and is approximately collimated. Laser beam 50d from array light-emitting unit 1d is reflected by second region 21bc, then reflected by fourth region 22bc, and is approximately collimated. This improves the focusing ability of laser beam 50, which is emitted from parabolic mirror 2c and then focused by focusing lens 4, and provides light source device 100 with good focusing ability for laser beams 50 from multiple light-emitting units 113. Note that other effects are the same as those of the first embodiment.

[0129] Figure 20 is a diagram illustrating a second example of reflection by a parabolic mirror according to the second embodiment, and is a cross-sectional view of a portion of each of the first reflecting surface 21c and the second reflecting surface 22d of the parabolic mirror 2d, viewed from the -Y direction.

[0130] 20, parabolic mirror 2d has second reflecting surface 22d instead of second reflecting surface 22c of parabolic mirror 2c. Second reflecting surface 22d includes third region 22ad and fourth region 22bd. Second reflecting surface 22d has a parabolic shape that protrudes toward the -Z direction in the X direction.

[0131] The focal point Fc1 of the first region 21ac overlaps with the focal point Fd3 of the third region 22ad. In other words, the focal points Fc1 and Fd3 are substantially coincident. Therefore, the laser beam 50c reflected by the first region 21ac toward the third region 22ad is substantially collimated by reflection from the third region 22ad, and then exits through the exit surface 23.

[0132] The focal point Fc2 of the second region 21bc overlaps with the focal point Fd4 of the fourth region 22bd. In other words, the focal points Fc2 and Fd4 are substantially coincident. Therefore, the laser beam 50d reflected by the second region 21bc toward the fourth region 22bd is substantially collimated by reflection from the fourth region 22bd, and then exits through the exit surface 23. The focal point Fc1 of the first region 21ac and the focal point Fc2 of the second region 21bc do not overlap.

[0133] Even with the shape of the parabolic mirror 2d having such a second reflecting surface 22d, it is possible to obtain the same effects as the parabolic mirror 2c.

[0134] In this embodiment, the first reflecting surface 21c and the second reflecting surface 22c each have two regions, but the present invention is not limited to this. The first reflecting surface 21c may have three or more regions with different focal points, and the second reflecting surface 22c may have three or more regions with different focal points. In this case, too, the laser beam 50 emitted from one light-emitting unit 113 is reflected by one region on the first reflecting surface 21c, and then reflected by one region on the second reflecting surface 22c that is paired with the one region on the first reflecting surface 21c, thereby being approximately collimated.

[0135] [Third embodiment] Next, a light source device 100e and a light source device 100f according to a third embodiment will be described. The light source device 100e is a first example of the third embodiment, and the light source device 100f is a second example of the third embodiment.

[0136] 21 is a perspective view showing the configuration around the parabolic mirror 2 in light source device 100e. As shown in Fig. 21, in light source device 100e, laser beam 50 emitted from array light emitting unit 1 is reflected by first reflecting surface 21 of parabolic mirror 2, then reflected by second reflecting surface 22, and emitted in the +Z direction through exit surface 23. Laser beam 50 emitted from exit surface 23 is focused by focusing lens 4 and enters the core of optical fiber 5 held by optical connector 7.

[0137] In this embodiment, the parabolic mirror 2 corresponds to one optical member, and the +Z direction in which the parabolic mirror 2 emits the laser beam 50 corresponds to the predetermined direction.

[0138] That is, light source device 100e does not include the stepped mirror 3 in the first embodiment, and emits laser beam 50 in the +Z direction by a parabolic mirror 2 corresponding to one optical member. With this configuration, the overall width Wx2 of the multiple laser beams 50 emitted by the multiple light-emitting units 113 can be made narrower than the overall width Wx1 (see FIG. 7), and the beam width D2 of laser beam 50 can be made narrower than the beam width D1 (see FIG. 10). As a result, aberration can be suppressed, and the focusing of laser beam 50 can be improved, and a light source device 100 can be provided that has good focusing of laser beams 50 from the multiple light-emitting units 113.

[0139] 22 is a perspective view showing the configuration of the periphery of the optical member group 60a in the light source device 100f. As shown in Fig. 22, in the light source device 100f, the laser beam 50 emitted from the array light emitting unit 1 is reflected by the fourth reflecting surface 621 of the second parabolic member 62, and then reflected by the fifth reflecting surface 631 of the third parabolic member 63 to enter the condenser lens 4. The laser beam 50 condensed by the condenser lens 4 enters the core of the optical fiber 5 held by the optical connector 7.

[0140] In this embodiment, the optical member group 60a corresponds to a plurality of optical members, and the +Z direction in which the optical member group 60a emits the laser beam 50 corresponds to the predetermined direction.

[0141] That is, the light source device 100f does not include the stepped mirror 3 in the first embodiment, and emits the laser beam 50 in the +Z direction using a first parabolic member 61, a second parabolic member 62, and a third parabolic member 63 corresponding to a plurality of optical members. With this configuration, the same effect as that of the light source device 100e can be obtained.

[0142] Although the embodiments and modifications have been described above, the embodiments disclosed herein should be considered to be illustrative and not restrictive in all respects. The scope of the present invention is defined by the claims, not by the meaning described above, and is intended to include all modifications within the meaning and scope of the claims.

[0143] All numbers such as ordinal numbers and quantities used in the description of the embodiments are merely examples for specifically explaining the technology of the present invention, and the present invention is not limited to the exemplified numbers.

[0144] The light source device according to the embodiment can be used for high-brightness lighting, projectors, displays, headlights, head-mounted displays, and the like. [Explanation of symbols]

[0145] 1 Array light emitting unit 11 packages 111 Bottom 112 Submount 113 Light-emitting part 113ca Light-emitting unit (example of first light-emitting unit) 113da Light-emitting unit (example of second light-emitting unit) 114 Light reflecting part 115 Side wall 12 Translucent member 13 Lens array 131a, 131b, 131c, 131d Collimating lenses 132 Connection 2. Parabolic mirror (an example of an optical member, an example of a first optical member) 20 Entrance plane 21 1st reflective surface 21ac 1st area 21bc 2nd area 22ac, 22ad 3rd area 22bc, 22bd 4th area 22 Second reflective surface 23 Exit surface 3. Step mirror (an example of an optical member, an example of a second optical member) 31 Plane part 32 Stepped reflective surface 32a First step surface (an example of a step surface) 32b Second step surface (an example of a step surface) 32c Third step surface (an example of a step surface) 32d Fourth step surface (an example of a step surface) 4. Condenser lens 5. Optical Fiber 51 Covering material 6 Light emitting part mounting board 610, 620 Electrical Connectors 60a Optical member group (an example of a plurality of optical members) 60b Optical components 61 First parabolic member (an example of an optical member) 611 Third Reflecting Surface (Example of First Reflecting Surface) 62 Second parabolic member (an example of an optical member) 621 Fourth Reflecting Surface (Example of First Reflecting Surface) 63 Third parabolic member (an example of an optical member) 631 Fifth Reflecting Surface (Example of Second Reflecting Surface) 641 6th Reflection Surface (Example of 1st Reflection Surface) 642 Seventh Reflecting Surface (an example of the first reflecting surface) 643 8th Reflection Surface (Example of 2nd Reflection Surface) 644 First step reflecting surface (an example of a step reflecting surface) 7 Optical Connector 71 Ferrule 711 Covering 72 Housing 50 Laser beam (example of light, example of laser light) 52 cores 53 Clad 51a First light column (example of a light column) 51b Second optical column (an example of an optical column) 51c Third Light Column (an example of a light column) 51d Fourth Light Column (an example of a light column) 100, 100a, 100b, 100c, 100e, 100f light source device 101 Case 101a Base member 101b, 101c cover members 102, 104 screw members 103 Connecting member 103a Ferrule insertion hole 103b Threaded part D1, D2 beam width (example of width) d1, d2 interval ha, hb, hc, hc height 1 / R1, 1 / R2 curvature F1, F2, Fc1, Fc2, Fc3, Fc4, Fd3, Fd4 focus Wx1, Wx2 Overall width along the X direction Wy1, Wy2 Overall width along the Y direction XX direction (example of arrangement direction) YY direction (an example of an orthogonal direction, an example of a predetermined direction) ZZ direction (an example of a specified direction)

Claims

1. a plurality of light-emitting units arranged at least along an arrangement direction; one or more optical members each having a first reflecting surface and a second reflecting surface, and each reflecting light from the plurality of light-emitting units and emitting the light in a predetermined direction; a condenser lens that condenses the light emitted from the one or more optical members, the first reflecting surface reflects the light emitted by the plurality of light emitting units toward the second reflecting surface; the second reflecting surface reflects the light reflected by the first reflecting surface, each of the first reflecting surface and the second reflecting surface has a curvature in the arrangement direction; a curvature of the second reflecting surface in the arrangement direction is larger than a curvature of the first reflecting surface in the arrangement direction, the plurality of light-emitting units are arranged along the arrangement direction and an orthogonal direction orthogonal to the arrangement direction, The one or more optical members are an optical element, a stepped reflecting surface having a plurality of stepped surfaces with different heights, which reflects the light reflected by the second reflecting surface toward the condensing lens; each of the plurality of step surfaces reflects a corresponding one of the plurality of light rows aligned along the orthogonal direction in pairs; each of the plurality of light columns includes a plurality of the light beams reflected by the second reflecting surface and aligned along the arrangement direction; The one optical member is a light source device having the first reflecting surface, the second reflecting surface, and the stepped reflecting surface integrally therewith.

2. The light source device according to claim 1 , wherein a focal point in at least a partial area of the first reflecting surface overlaps a focal point in at least a partial area of the second reflecting surface.

3. the plurality of light-emitting units include at least a first light-emitting unit and a second light-emitting unit, the first reflecting surface includes a first region that reflects the light emitted by the first light-emitting unit and a second region that reflects the light emitted by the second light-emitting unit; the second reflecting surface includes a third region that reflects light emitted by the first light-emitting unit and reflected by the first reflecting surface, and a fourth region that reflects light emitted by the second light-emitting unit and reflected by the first reflecting surface, a focus of the first region overlaps with a focus of the third region; The light source device according to claim 1 , wherein the focal point of the second region overlaps with the focal point of the fourth region.

4. each of the plurality of light-emitting units emits a laser beam; a width of the laser light emitted by the light emitting unit along the arrangement direction at a position where the laser light is reflected by the second reflecting surface is narrower than a width of the laser light at a position where the laser light is incident on the first reflecting surface, 4. A light source device as described in any one of claims 1 to 3, wherein the spacing between the multiple laser beams emitted by the multiple light-emitting elements is narrower along the specified direction at the position where the laser beams are reflected by the step reflecting surface than along the orthogonal direction at the position where the laser beams are incident on the step reflecting surface.

5. The optical fiber further includes a core and a cladding surrounding the core, 5. The light source device according to claim 1, wherein the light condensed by the condenser lens is incident on the core of the optical fiber.

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