Light-emitting module

Abstract

To provide a light emitting module capable of reducing the deviation between the direction of travel of a laser beam emitted from a semiconductor laser element and the designed direction of travel.SOLUTION: A light emitting module comprises a support substrate having a plurality of mounting surfaces aligned in the first direction, a plurality of semiconductor laser elements disposed on respective ones of the plurality of mounting surfaces, each semiconductor element configured to emit a laser beam, a plurality of first mirror members, each of which has a first reflecting surface for changing the travel direction of the laser beam, and a plurality of second mirror members, each of which has a second reflecting surface for reflecting the laser beam reflected by the first reflecting surface in the second direction, the positions of the second reflecting surfaces of the plurality of second mirror members in the second direction are different from each other.SELECTED DRAWING: Figure 2G

Description

Technical Field

[0001] The present disclosure relates to a light-emitting module.

Background Art

[0002] In recent years, with the increase in the output power of semiconductor laser elements, technologies are being developed to use laser light not as an excitation light source for semiconductor laser elements but as a light source for directly irradiating materials for processing. Such a technology is called direct diode laser (DDL) technology.

[0003] In DDL technology, a light-emitting module including a plurality of semiconductor laser elements is used. The light-emitting module combines a plurality of laser lights obtained by emitting laser lights from each of the plurality of semiconductor laser elements and emits a high-output laser light. When the traveling directions of the plurality of laser lights are aligned in the same direction as designed, the plurality of laser lights can be effectively combined. Patent Document 1 discloses an example of an optical component capable of reducing the deviation between the traveling direction of the laser light emitted from the semiconductor laser element and the designed traveling direction.

Prior Art Documents

Patent Documents

[0004]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0005] Provided is a light-emitting module capable of effectively combining a plurality of laser lights obtained by emitting laser lights from each of a plurality of semiconductor laser elements.

Means for Solving the Problems

[0006] In one embodiment, the light-emitting module of the present disclosure comprises: a support base having a plurality of mounting surfaces aligned in a first direction; a plurality of semiconductor laser elements, each having a corresponding semiconductor laser element disposed on each of the plurality of mounting surfaces, each semiconductor laser element emitting laser light; a plurality of first mirror members, each having a first reflective surface, the first reflective surface reflecting the laser light and changing the direction of propagation of the laser light; a plurality of second mirror members, each having a second reflective surface, at least a portion of the second reflective surface located above at least a portion of the first reflective surface, the second reflective surface reflecting the laser light reflected by the first reflective surface in a second direction intersecting the first direction; wherein the positions of the second reflective surfaces of the plurality of second mirror members in the second direction are different from one another. [Effects of the Invention]

[0007] According to embodiments of this disclosure, it is possible to realize a light-emitting module that can effectively combine multiple laser beams obtained by emitting laser light from each of multiple semiconductor laser elements. [Brief explanation of the drawing]

[0008] [Figure 1A] Figure 1A is a schematic top view showing the configuration of an exemplary light-emitting module according to Embodiment 1 of the present disclosure. [Figure 1B] Figure 1B is a schematic side view showing the configuration of an exemplary light-emitting module according to Embodiment 1 of the present disclosure. [Figure 1C] Figure 1C is another schematic side view illustrating the configuration of a light-emitting module according to an exemplary embodiment 1 of the present disclosure. [Figure 1D] Figure 1D is a schematic top view showing the configuration of a modified example of the light-emitting module according to Embodiment 1 of the present disclosure. [Figure 2A] Figure 2A is a schematic perspective view showing an example of the configuration of a light-emitting device according to an exemplary embodiment 1 of the present disclosure. [Figure 2B] Figure 2B is a schematic perspective view showing another example of the configuration of a light-emitting device according to exemplary embodiment 1 of the present disclosure. [Figure 2C] Figure 2C is an exploded perspective view of the light-emitting device shown in Figure 2B. [Figure 2D] Figure 2D is another exploded perspective view of the light-emitting device shown in Figure 2B. [Figure 2E] Figure 2E is a perspective view from below of the frame included in the light-emitting device shown in Figure 2D. [Figure 2F] Figure 2F is a top view of the light-emitting device shown in Figure 2B, with the second mirror member and cover omitted. [Figure 2G] Figure 2G is a cross-sectional view of the light-emitting device shown in Figure 2B, parallel to the YZ plane. [Figure 3A] Figure 3A is a schematic perspective view showing an example of the configuration of a light-emitting device according to an exemplary embodiment 2 of the present disclosure. [Figure 3B] Figure 3B is a schematic perspective view showing another example of the configuration of a light-emitting device according to exemplary embodiment 2 of the present disclosure. [Figure 3C] Figure 3C is a cross-sectional view of the light-emitting device shown in Figure 3B, parallel to the YZ plane. [Figure 3D] Figure 3D is a schematic perspective view showing the configuration of the support included in the light-emitting device shown in Figures 3A and 3B. [Figure 4] Figure 4 is a schematic diagram showing the configuration of a DDL device according to an exemplary embodiment 3 of this disclosure. [Figure 5A] Figure 5A is an exploded perspective view schematically showing an example of the configuration of a laser light source included in the light-emitting device according to Embodiment 1. [Figure 5B] Figure 5B is a cross-sectional view of the laser light source shown in Figure 5A, parallel to the YZ plane. [Figure 6A] Figure 6A is a schematic perspective view showing an example of the configuration of a laser light source included in the light-emitting device according to Embodiment 2. [Figure 6B] Figure 6B is a schematic diagram showing the internal planar configuration of the laser light source shown in Figure 6A. [Modes for carrying out the invention]

[0009] Hereinafter, a light-emitting module according to an embodiment of the present disclosure and a light-emitting device included in the light-emitting module will be described with reference to the drawings. Parts denoted by the same reference numerals in the plurality of drawings indicate the same or equivalent parts.

[0010] Furthermore, the embodiments described below are examples for embodying the technical idea of the present invention, and do not limit the present invention thereto. In addition, descriptions of the size, material, shape, relative arrangement, etc. of the components are not intended to limit the scope of the present invention only thereto, but are intended to be illustrative. The sizes and positional relationships of the members shown in each drawing may be exaggerated for ease of understanding.

[0011] In this specification or the claims, with respect to polygons such as triangles or quadrilaterals, shapes that have been processed such as rounding, chamfering, angling, or rounding at the corners of the polygon are also referred to as polygons. Also, not limited to the corners (ends of the sides), shapes that have been processed in the middle part of the sides are likewise referred to as polygons. That is, shapes that have been partially processed while leaving the polygon as a base are included in the interpretation of "polygon" described in this specification and the claims.

[0012] (Embodiment 1) [Light-Emitting Module] First, an example of the configuration of a light-emitting module according to Embodiment 1 of this disclosure will be described with reference to Figures 1A to 1C. Figure 1A is a schematic top view showing the configuration of a light-emitting module according to exemplary Embodiment 1 of this disclosure. Figure 1B is a schematic side view showing the configuration of a light-emitting module according to exemplary Embodiment 1 of this disclosure. Figure 1C is another schematic side view showing the configuration of a light-emitting module according to exemplary Embodiment 1 of this disclosure. In these figures, mutually orthogonal X, Y, and Z axes are schematically shown for reference. The direction of the arrow on the X axis is referred to as the +X direction, and the opposite direction is referred to as the -X direction. When the ±X directions are not distinguished, they are simply referred to as the X direction. The same applies to the Y and Z directions. In this specification, for the sake of clarity of explanation, the +Y direction is referred to as "upward" and the -Y direction is referred to as "downward". This does not restrict the orientation of the light-emitting module when it is used, and the orientation of the light-emitting module is arbitrary.

[0013] The light-emitting module 200 shown in Figures 1A to 1C comprises a support base 60A, a focusing lens 70, an optical fiber 80, a support member 82 for supporting the optical fiber 80, a plurality of slow-axis collimating lenses 92, a plurality of mirror members 94, and a plurality of light-emitting devices 100A. Each mirror member 94 has a reflective surface 94s.

[0014] As shown in Figure 1B, the support base 60A is positioned on a reference plane Ref parallel to the XZ plane. The reference plane Ref is the height reference plane for the light-emitting module 200. The "height" described below is the height from this reference plane. As shown in Figure 1A, the support base 60A includes a first part 60A1 that supports a plurality of light-emitting devices 100A. The support base 60A further includes a plurality of second parts 60A2 supported by the first part 60A1. Each second part 60A2 supports the corresponding slow-axis collimating lens 92 and mirror member 94. The support base 60A further includes a third part 60A3 connected to the first part 60A1. The third part 60A3 supports the focusing lens 70 and optical fiber 80.

[0015] The first part 60A1 has a plurality of first mounting surfaces 60s1 arranged in the X direction. A corresponding second part 60A2 is disposed on each first mounting surface 60s1. Each second part 60A2 has a second mounting surface 60s2. The third part 60A3 has a third mounting surface 60s3.

[0016] As shown in Figure 1A, a corresponding light-emitting device 100A is arranged on each first mounting surface 60s1. A corresponding slow-axis collimating lens 92 and mirror member 94 are arranged on each second mounting surface 60s2. If the slow-axis collimating lens 92 and / or mirror member 94 have sufficiently large dimensions in the Y direction, the slow-axis collimating lens 92 and / or mirror member 94 may be placed on the first mounting surface 60s1 without going through the second portion 60A2. A condensing lens 70 is arranged on the third mounting surface 60s3, and an optical fiber 80 is arranged via a support member 82.

[0017] From the above arrangement, the following can be said: Each light-emitting device 100A is directly supported by the corresponding first mounting surface 60s1. Each slow-axis collimating lens 92 and each mirror member 94 are directly supported by the corresponding second mounting surface 60s2. Each slow-axis collimating lens 92 and each mirror member 94 are further indirectly supported by the corresponding first mounting surface 60s1 via the corresponding second portion 60A2. The focusing lens 70 is directly supported by the third mounting surface 60s3, and the optical fiber 80 is indirectly supported by the third mounting surface 60s3 via the support member 82.

[0018] The multiple first mounting surfaces 60s1 are located on the same plane parallel to the XZ plane. Therefore, the heights of the multiple first mounting surfaces 60s1 are equal to each other. In contrast, the heights of the multiple second mounting surfaces 60s2 decrease gradually along the +X direction. The height of the third mounting surface 60s3 is greater than the height of the first mounting surface 60s1. Furthermore, the height of the third mounting surface 60s3 is less than the minimum height of the multiple second mounting surfaces 60s2. Depending on the dimensions of the condensing lens 70 in the Y direction, the height of the third mounting surface 60s3 may be equal to or less than the height of the first mounting surface 60s1.

[0019] In the examples shown in Figures 1A to 1C, there are four light-emitting devices 100A and four first mounting surfaces 60s1, but the number is not limited to these. The number of light-emitting devices 100A may be two, three, or five or more. The more light-emitting devices 100A there are, the higher the output laser light that can be obtained. The number of first mounting surfaces 60s1 may be two, three, or five or more, or may be equal to or greater than the number of light-emitting devices 100A.

[0020] The support substrate 60A may be formed from a ceramic selected from the group consisting of AlN, SiN, SiC, and alumina, for example. Alternatively, the support substrate 60A may be formed from at least one metallic material selected from the group consisting of Cu, Al, and Ag, for example. The support substrate 60A may be formed from a metal matrix composite material in which diamond particles are dispersed in at least one metallic material selected from the group consisting of Cu, Al, and Ag, for example. The support substrate 60A may be formed integrally or as an assembly of multiple parts. The multiple parts may be formed from the same material or from different materials. For example, the first part 60A1, multiple second parts 60A2, and third part 60A3 may be formed integrally or independently of each other. Alternatively, the first portion 60A1 and the third portion 60A3 may be formed integrally, and the multiple second portions 60A2 may be formed independently of the first portion 60A1 and the third portion 60A3.

[0021] The support base 60A is preferably formed from a metallic material selected from the group consisting of Cu, Al, and Ag, and is made from a single component. Metallic materials have better heat dissipation than ceramics and are also softer, making them easier to process.

[0022] The support base 60A functions as a support base on which multiple light-emitting devices 100A are arranged. The support base 60A can also function as a heat sink that transfers heat emitted from the multiple light-emitting devices 100A to the outside, thereby reducing excessive temperature rise of the light-emitting devices 100A. In this case, one or more flow channels for liquid cooling may be provided inside the support base 60A. For example, water can be used as the liquid for liquid cooling. Alternatively, a fin structure for air cooling may be provided on the surface of the support base 60A. Or, if the support base 60A is placed on a separately prepared heat sink, the support base 60A can also function as a heat spreader that transfers heat emitted from the multiple light-emitting devices 100A to the heat sink.

[0023] Each light-emitting device 100A emits laser light L in the +Z direction. The direction of propagation of the laser light L is parallel to the same plane in which the multiple light-emitting devices 100A are arranged. While the multiple light-emitting devices 100A are arranged on the same plane, the height of the optical axis of the laser light L emitted from the multiple light-emitting devices 100A decreases in steps along the +X direction, as shown in Figures 1B and 1C. The specific configuration of the light-emitting devices 100A that can have different heights of the optical axis of the laser light L will be described later. In this specification, "optical axis of the laser light" means the axis passing through the center of the far-field pattern of the laser light. Laser light traveling along the optical axis shows a peak intensity in the light intensity distribution of the far-field pattern.

[0024] Since the heights of the multiple first mounting surfaces 60s1 are equal, the variation in the amount of heat emitted from the multiple light-emitting devices 100A and transferred to the reference plane Ref can be reduced compared to a configuration in which the heights of the multiple first mounting surfaces 60s1 are different. If the first part 60A1 has a flow channel extending along the X direction below the multiple first mounting surfaces 60s1, the variation in the degree of cooling of the multiple light-emitting devices 100A can be reduced by flowing liquid through the flow channel. Therefore, the heat dissipation efficiency from the multiple light-emitting devices 100A can be improved in the light-emitting module 200.

[0025] Each slow-axis collimating lens 92, as shown in Figure 1A, collimates the laser beam emitted from the corresponding light-emitting device 100A and traveling in the +Z direction in the XZ plane. The reflective surfaces 94s of each mirror member 94, as shown in Figures 1A and 1B, reflect the collimated laser beam L emitted from the corresponding light-emitting device 100A, changing the direction of the laser beam L toward the focusing lens 70 in the +X direction. The laser beam L emitted from each light-emitting device 100A is represented by a thick line with three arrows in the example shown in Figure 1A, and by a thick line with one arrow in the examples shown in Figures 1B and 1C. In the example shown in Figure 1A, the laser beam L is represented by a thick line with three arrows to emphasize that the laser beam L has a broad beam.

[0026] The focusing lens 70 comprises a fast-axis focusing lens 70a and a slow-axis focusing lens 70b. The fast-axis focusing lens 70a may be, for example, a cylindrical lens having a uniform cross-sectional shape in the Z direction, and the slow-axis focusing lens 70b may be, for example, a cylindrical lens having a uniform cross-sectional shape in the Y direction. The optical axes of the fast-axis focusing lens 70a and the slow-axis focusing lens 70b are parallel to the X direction. The focusing lens 70 may be formed from at least one translucent material selected from the group consisting of, for example, glass, silicon, quartz, synthetic quartz, sapphire, transparent ceramics, silicone resin, and plastic.

[0027] The fast-axis focusing lens 70a is positioned so that its focal point approximately coincides with the optical incident end 80a of the optical fiber 80. Similarly, the slow-axis focusing lens 70b is positioned so that its focal point approximately coincides with the optical incident end 80a of the optical fiber 80. The focal length of the fast-axis focusing lens 70a is longer than the focal length of the slow-axis focusing lens 70b. As shown in Figure 1B, the fast-axis focusing lens 70a focuses the multiple laser beams L emitted from each of the multiple light-emitting devices 100A in the XY plane onto the optical incident end 80a of the optical fiber 80. As shown in Figure 1A, the slow-axis focusing lens 70b focuses the spread laser beams L emitted from each of the multiple light-emitting devices 100A onto the optical incident end 80a in the XZ plane.

[0028] As described above, the laser beam L emitted in the +Z direction from each of the multiple light-emitting devices 100A is reflected in the +X direction by the corresponding reflective surface 94s. The focusing lens 70 allows the multiple laser beams L thus obtained to be combined and injected into the optical fiber 80.

[0029] As a result, the light-emitting module 200 emits combined light, which is the combined output of multiple laser beams L, from the optical output end 80b of the optical fiber 80. The output of the combined light is roughly equal to the output of the laser beams L emitted from each light-emitting device 100A multiplied by the number of light-emitting devices 100A. Therefore, increasing the number of light-emitting devices 100A can increase the output of the combined light.

[0030] Next, a modified example of the light-emitting module 200 according to Embodiment 1 of the present disclosure will be described with reference to Figure 1D. Figure 1D is a schematic top view showing the configuration of a modified example of the light-emitting module according to Embodiment 1 of the present disclosure. The light-emitting module 210 shown in Figure 1D differs from the light-emitting module 200 shown in Figures 1A to 1C in the following three points.

[0031] The first point is that the light-emitting module 210 includes a support base 62A instead of a support base 60A. The shape of the support base 62A is different from the shape of the support base 60A. The second point is that the light-emitting module 210 further includes a plurality of light-emitting devices 100A1, a plurality of slow-axis collimating lenses 92a, and a plurality of mirror members 94a, in addition to a plurality of light-emitting devices 100A2, a plurality of slow-axis collimating lenses 92b, and a plurality of mirror members 94b. Each mirror member 94a has a reflective surface 94as, and each mirror member 94b has a reflective surface 94bs. The third point is that the light-emitting module 210 further includes a mirror member 94c, a half-wave plate 96, and a polarizing beam splitter 98. The mirror member 94c has a reflective surface 94cs.

[0032] The support base 62A comprises a first portion 62A1 that supports a plurality of light-emitting devices 100A1 and a plurality of light-emitting devices 100A2. The support base 62A further comprises a plurality of second portions 62A2 supported by the first portion 62A1. Each second portion 62A2 supports a corresponding slow-axis collimating lens 92a, a slow-axis collimating lens 92b, a mirror member 94a, and a mirror member 94b. The support base 62A further comprises a third portion 62A3 connected to the first portion 62A1. The third portion 62A3 supports a focusing lens 70, an optical fiber 80, a mirror member 94c, a half-wave plate 96, and a polarizing beam splitter 98.

[0033] The first part 62A1 has a plurality of first mounting surfaces 60s1 arranged in the X direction. A corresponding second part 62A2 is positioned on each first mounting surface 60s1. Each second part 62A2 has a second mounting surface 60s2. The third part 62A3 has a third mounting surface 60s3. The mounting surfaces 60s1 to 60s3 are as described above.

[0034] The light-emitting device 100A1, the retard-axis collimating lens 92a, and the mirror member 94a have the same structure as the light-emitting device 100A, the retard-axis collimating lens 92, and the mirror member 94 shown in Figure 1A, respectively. The same applies to the light-emitting device 100A2, the retard-axis collimating lens 92b, and the mirror member 94b. The light-emitting device 100A1, the retard-axis collimating lens 92a, and the mirror member 94a are arranged in this order along the +Z direction, and the light-emitting device 100A2, the retard-axis collimating lens 92b, and the mirror member 94b are arranged in this order along the -Z direction. The arrangement of the light-emitting devices 100A1 and 100A2 is inversely related to each other in the Z direction. The same applies to the arrangement of the retard-axis collimating lenses 92a and 92b, and the arrangement of the mirror member 94a and the mirror member 94b.

[0035] Each light-emitting device 100A1 and each light-emitting device 100A2 are positioned on the corresponding first mounting surface 60s1. Each light-emitting device 100A1 emits laser light La in the +Z direction, and each light-emitting device 100A2 emits laser light Lb in the -Z direction. The polarization directions of the laser light La and Lb are parallel to the X direction. Each retard-axis collimating lens 92a, each retard-axis collimating lens 92b, each mirror member 94a, and each mirror member 94b are positioned on the corresponding second mounting surface 60s2. Each retard-axis collimating lens 92a collimates the laser light La emitted from the corresponding light-emitting device 100A1 in the +Z direction in the XZ plane. Each retard-axis collimating lens 92b collimates the laser light Lb emitted from the corresponding light-emitting device 100A2 in the -Z direction in the XZ plane. The reflective surface 94as of each mirror member 94a reflects the collimated laser beam La, changing the direction of propagation of the laser beam La in the +X direction. The reflective surface 94bs of each mirror member 94b reflects the collimated laser beam Lb, changing the direction of propagation of the laser beam Lb in the +X direction.

[0036] The mirror member 94c, the half-wave plate 96, and the polarizing beam splitter 98 are arranged on the third mounting surface 60s3. The reflective surface 94cs of the mirror member 94c reflects the laser light Lb traveling in the +X direction, changing the direction of the laser light Lb to the -Z direction. The half-wave plate 96 changes the polarization direction of the laser light Lb traveling in the -Z direction from the X direction to the Y direction. The polarizing beam splitter 98 transmits the laser light La traveling in the +X direction with a polarization direction in the Z direction, and reflects the laser light Lb traveling in the -Z direction with a polarization direction in the Y direction. The laser light La that has passed through the polarizing beam splitter 98 is focused by the focusing lens 70 to the optical incident end 80a of the optical fiber 80. Similarly, the laser light Lb reflected by the polarizing beam splitter 98 is focused by the focusing lens 70 to the optical incident end 80a of the optical fiber 80.

[0037] As a result, the light-emitting module 210 emits combined light, which is the combined light of multiple laser beams La and multiple laser beams Lb, from the optical output end 80b of the optical fiber 80. In the light-emitting module 210 illustrated in Figure 1D, the total number of light-emitting devices 100A1 and 100A2 is twice the number of light-emitting devices 100A compared to the light-emitting module 200 illustrated in Figure 1A. Therefore, the output of the combined light can be further increased.

[0038] In the light-emitting module 200, if the propagation directions of the multiple laser beams L are aligned in the +X direction as designed, the multiple laser beams L can be effectively combined by the focusing lens 70 and injected into the optical fiber 80. The same applies to the light-emitting module 210, where the propagation directions of the multiple laser beams La and multiple laser beams Lb are aligned in the +X direction as designed.

[0039] Furthermore, instead of using the multiple light-emitting devices 100A in the light-emitting module 200 according to Embodiment 1 and the light-emitting module 210 of its modified form, a more general spatially coupled light-emitting module may be used.

[0040] [Light-emitting device] The configuration example of the light-emitting device according to Embodiment 1 of this disclosure will be described below with reference to Figures 2A to 2G. According to the light-emitting device according to Embodiment 1 of this disclosure, it is possible to reduce the discrepancy between the direction of propagation of the laser light L and the design direction of propagation. In this specification, when the term "direction of propagation" is used, such as "direction of propagation of the laser light," the "direction of propagation" refers to the actual direction of propagation.

[0041] Figure 2A is a schematic perspective view showing an example of the configuration of a light-emitting device according to exemplary embodiment 1 of the present disclosure. Figure 2B is a schematic perspective view showing another example of the configuration of a light-emitting device according to exemplary embodiment 1 of the present disclosure. The light-emitting device 100A shown in Figure 2A corresponds to the light-emitting device 100A furthest from the focusing lens 70 in the X direction among the plurality of light-emitting devices 100A shown in Figure 1A. The light-emitting device 100A shown in Figure 2B corresponds to the light-emitting device 100A closest to the focusing lens 70 in the X direction among the plurality of light-emitting devices 100A shown in Figure 1A. Figure 2C is an exploded perspective view of the light-emitting device shown in Figure 2B. The light-emitting device 100A shown in Figure 2C comprises a substrate 10, a laser light source 20, a first mirror member 30a, a second mirror member 30b, a frame 40, a plurality of wires 40w, and a cover 50. The substrate 10 has a mounting surface 10us. The first mirror member 30a has a first reflective surface 30as, and the second mirror member 30b has a second reflective surface 30bs. The laser light source 20 is a chip-on-submount type semiconductor laser light source having a semiconductor laser element 22. The light-emitting device 100A may further include a protective element such as a Zener diode and / or a temperature measuring element for measuring the internal temperature such as a thermistor. Figure 2D is another exploded perspective view of the light-emitting device 100A shown in Figure 2B. In Figure 2D, the multiple wires 40w shown in Figure 2C are omitted. Figure 2E is a perspective view from below of the frame 40 included in the light-emitting device 100A shown in Figure 2D. Figure 2F is a top view of the configuration of the light-emitting device 100A shown in Figure 2B with the second mirror member 30b and cover 50 omitted. Figure 2G is a cross-sectional view of the light-emitting device 100A shown in Figure 2B, parallel to the YZ plane.

[0042] As will be explained in detail later, in the light-emitting device 100A according to Embodiment 1, as shown in Figure 2G, the laser light L emitted from the laser light source 20 is reflected in this order by the first reflective surface 30as and the second reflective surface 30bs. With such a configuration, regardless of whether the direction of propagation of the laser light L emitted from the laser light source 20 deviates from the design direction of propagation, which is the +Z direction, the direction of propagation of the laser light L reflected in this order by the first reflective surface 30as and the second reflective surface 30bs can be directed in the +Z direction. The first reflective surface 30as reflects the laser light L emitted from the laser light source 20, changing the direction of propagation of the laser light L away from the mounting surface 10us of the substrate 10. The second reflective surface 30bs reflects the laser light L reflected by the first reflective surface 30as, further changing the direction of propagation of the laser light L in the +Z direction.

[0043] Furthermore, in the light-emitting device 100A according to Embodiment 1, as shown in Figures 2A and 2B, the height of the optical axis of the laser beam L reflected by the second reflective surface 30bs of the second mirror member 30b can be reduced as it is shifted along the +Z direction. Therefore, even if multiple light-emitting devices 100A are arranged on the same plane, the heights of the optical axes of the laser beam L emitted from the multiple light-emitting devices 100A can be made to differ from one another. In the light-emitting module 200 shown in Figures 1A to 1C, the positions of the second reflective surfaces 30bs of the multiple second mirror members 30b in the +Z direction differ in steps along the +X direction and in the +Z direction. As a result, the heights of the optical axes of the laser beam L emitted from the multiple light-emitting devices 100A differ in steps along the +X direction.

[0044] The position and orientation of the second mirror member 30b can be adjusted so that the laser beam L reflected by the second reflective surface 30bs travels in the +Z direction at an appropriate optical axis height. By reflecting the laser beam L reflected by the second reflective surface 30bs at the reflective surface 94s as shown in Figure 1A, the direction of travel of the laser beam L can be changed to the +X direction, which is the design direction of travel. As a result, multiple laser beams L traveling in the +X direction can be effectively combined to output high-power combined light from the light-emitting module 200.

[0045] In configurations where the direction of propagation of the laser beam L incident on the reflective surface 94s is not parallel to the design's +Z direction, the direction of propagation of the laser beam L reflected by the reflective surface 94s deviates from the design's +X direction. Multiple laser beams L with such deviations in their direction of propagation will not effectively combine, even if the deviation angle is only a few degrees, potentially leading to a decrease in the output of the combined light.

[0046] In contrast, in Embodiment 1, the deviation between the direction of propagation of the laser light L reflected in this order by the first reflective surface 30as and the second reflective surface 30bs and the design direction of propagation, which is the +Z direction, can be reduced. As a result, the deviation between the direction of propagation of the laser light L reflected by the reflective surface 94s and the design direction of propagation, which is the +X direction, can be reduced. The angle between the direction of propagation of the laser light L and the design direction of propagation is preferably 1° or less, and more preferably 0.1° or less. In this specification, the angle between the two directions has a positive value and does not have a negative value.

[0047] In Embodiment 1, the design direction of propagation of the laser beam L reflected in this order from the first reflective surface 30as and the second reflective surface 30bs is parallel to the +Z direction, and the design direction of propagation of the laser beam L reflected from the reflective surface 94s is parallel to the +X direction. However, the design direction of propagation is not limited to these directions.

[0048] In this specification, the direction in which multiple first mounting surfaces 60s1 are aligned is referred to as the "first direction," and the direction of propagation of the laser light L reflected in this order by the first reflective surface 30as and the second reflective surface 30bs is referred to as the "second direction." The reference plane Ref is parallel to the first direction. In Embodiment 1, the first direction is the +X direction and the second direction is the +Z direction, but the invention is not limited to these directions. The second direction does not need to be perpendicular to the first direction as long as it intersects with the first direction. The same applies to Embodiment 2, which will be described later.

[0049] Note that the light-emitting device 100A may be used for purposes other than those shown in the light-emitting module 200 in Figures 1A to 1C.

[0050] The following describes each component of the light-emitting device 100A.

[0051] <Substrate 10> As shown in Figure 2D, the substrate 10 has a mounting surface 10us and a bottom surface 10Ls. The normal direction of the mounting surface 10us is the +Y direction. In this specification, the normal direction of a surface means the direction perpendicular to the surface and away from the object having the surface. In the example shown in Figure 2D, the substrate 10 has a rectangular flat plate shape, but is not limited to this shape. The substrate 10 may have, for example, a circular or elliptical flat plate shape. The bottom surface 10Ls of the substrate 10 is joined to the first mounting surface 60s1 of the support base 60A via an inorganic bonding member such as solder.

[0052] The substrate 10 may be formed from a material having a thermal conductivity of 10 W / m·K or more and 2000 W / m·K or less. Such a high thermal conductivity allows the heat emitted from the laser light source 20 during operation to be effectively transferred to the support base 60A shown in Figures 1A to 1C via the substrate 10. The substrate 10 may be formed from the same material as the support base 60A. The dimensions of the substrate 10 in the X direction may be, for example, 1000 μm or more and 10000 μm or less, the dimensions in the Y direction may be, for example, 100 μm or more and 5000 μm or less, and the dimensions in the Z direction may be, for example, 1000 μm or more and 20000 μm or less.

[0053] <Laser light source 20> As shown in Figure 2D, the laser light source 20 is supported by the mounting surface 10us of the substrate 10. The laser light source 20 comprises a submount 21, an end-face emission type semiconductor laser element 22 supported by the submount 21, a lens support member 23, and a velocity-axis collimating lens 24. The semiconductor laser element 22 is supported by the mounting surface 10us of the substrate 10 via the submount 21. The semiconductor laser element 22 is positioned to emit laser light L toward the first reflection surface 30as. The lens support member 23 has a shape that straddles the semiconductor laser element 22. The lens support member 23 supports the velocity-axis collimating lens 24 by its end face. The components of the laser light source 20 may also be treated as components of the light-emitting device 100A.

[0054] The semiconductor laser element 22 emits laser light L from its rectangular end face. When this end face extends in the X direction and is a plane parallel to the XY plane, the laser light L emitted from the semiconductor laser element 22 in the +Z direction spreads relatively quickly in the YZ plane and relatively slowly in the XZ plane. The speed axis direction of the laser light L is parallel to the Y direction, and the slow axis direction is parallel to the X direction.

[0055] The laser light source 20 emits laser light from a semiconductor laser element 22, which has passed through a velocity-axis collimating lens 24. The laser light L emitted from the laser light source 20 is collimated in the YZ plane but not in the XZ plane. In this specification, "collimating" means not only making the laser light L parallel, but also reducing the divergence angle of the laser light L. The specific configuration of the laser light source 20 will be described later.

[0056] As shown in Figure 2G, the semiconductor laser element 22 included in the laser light source 20 is sealed by a substrate 10, a frame 40, and a cover 50. Hermetically sealed sealing is preferable. The effect of hermetically sealed sealing increases as the wavelength of the laser light emitted from the semiconductor laser element 22 becomes shorter. In a configuration where the semiconductor laser element 22 is not hermetically sealed and the emission surface is in contact with the outside air, the shorter the wavelength of the laser light, the higher the possibility that the emission surface will deteriorate during operation due to dust collection.

[0057] Alternatively, instead of the end-face emitting semiconductor laser element 22, a surface-emitting semiconductor laser element such as a VCSEL (Vertical-Cavity Surface-Emitting Laser) element may be used. The surface-emitting semiconductor laser element is arranged so that the laser light emitted from the semiconductor laser element propagates in the +Z direction.

[0058] <First mirror member 30a and second mirror member 30b> As shown in Figure 2D, the first mirror member 30a is supported by the mounting surface 10us of the substrate 10. The first mirror member 30a has a uniform cross-sectional shape in the X direction. This cross-sectional shape is approximately triangular. The first mirror member 30a has a bottom surface, a back surface, and a slope connecting the bottom surface and the back surface. The bottom surface is parallel to the XZ plane, and the back surface is parallel to the XY plane. The normal direction of the slope is parallel to the YZ plane, and forms an acute angle with the +Y direction and an acute angle with the -Z direction. The angle between the bottom surface and the slope of the first mirror member 30a is 45°, but is not limited to this angle and may be, for example, 30° or more and 60° or less.

[0059] The first mirror member 30a has a first reflective surface 30as on the above-mentioned inclined surface. The first reflective surface 30as is inclined with respect to the mounting surface 10us of the substrate 10 and faces diagonally upward. In this specification, diagonally upward means a direction that makes an angle of 30° or more and 60° or less with respect to the +Y direction. The normal direction of the first reflective surface 30as may or may not be parallel to the YZ plane, as long as the first reflective surface 30as can receive the laser light L emitted from the laser light source 20 and the normal direction of the first reflective surface 30as makes an angle of 30° or more and 60° or less with respect to the +Y direction.

[0060] As shown in Figure 2G, the first reflective surface 30as reflects the laser beam L emitted from the laser light source 20, changing the direction of the laser beam L away from the mounting surface 10us of the substrate 10. It can also be said that the first reflective surface 30as reflects the laser beam L, changing the direction of the laser beam L away from the first mounting surface 60s1 shown in Figures 1A to 1C. The angle between the direction in which the laser beam L moves away from the mounting surface 10us or the first mounting surface 60s1 of the substrate 10 and the normal direction of the mounting surface 10us may be, for example, 0° or more and 5° or less. Since there is a tolerance of 5° for this angle, it is not necessary to adjust the position and orientation of the first mirror member 30a as precisely as the position and orientation of the second mirror member 30b.

[0061] As shown in Figure 2D, the second mirror member 30b is supported by the upper surface 50us of the cover 50. The second mirror member 30b has a uniform cross-sectional shape in the X direction. This cross-sectional shape is approximately trapezoidal. The second mirror member 30b has an upper surface, a lower surface, and a slope connecting the upper and lower surfaces. The upper and lower surfaces are each parallel to the XZ plane. The dimension of the lower surface in the X direction is equal to the dimension of the upper surface in the X direction. On the other hand, the dimension of the lower surface in the Z direction is smaller than the dimension of the upper surface in the Z direction. The normal direction of the slope is parallel to the YZ plane, and forms an acute angle with the -Y direction and an acute angle with the +Z direction. The angle between the upper surface and the slope of the second mirror member 30b is 45°, but is not limited to this angle and may be, for example, 30° or more and 60° or less. The angle between the upper surface and the inclined surface of the second mirror member 30b may be equal to or different from the angle between the lower surface and the inclined surface of the first mirror member 30a.

[0062] The second mirror member 30b has a second reflective surface 30bs on the above-mentioned inclined surface. At least a portion of the second reflective surface 30bs is located above at least a portion of the first reflective surface 30as. As shown in Figure 2G, the second reflective surface 30bs reflects the laser light L reflected by the first reflective surface 30as, changing the direction of propagation of the laser light L in the +Z direction.

[0063] As shown in Figure 2G, a resin layer 32 exists between the lower surface of the second mirror member 30b and the upper surface 50us of the cover 50. The resin layer 32 is formed by curing the resin while the lower surface of the second mirror member 30b is in contact with the upper surface 50us of the cover 50 via the uncured resin. The resin may be, for example, a thermosetting resin that is cured by heating, or a photocurable resin that is cured by irradiation with ultraviolet or visible light. Before curing the resin, the following active alignment is performed. That is, with the laser light source 20 emitting laser light L, the position and orientation of the second mirror member 30b are appropriately adjusted so that the second reflective surface 30bs changes the direction of propagation of the laser light L in the +Z direction. Such adjustment can be performed after the light-emitting device 100A is placed on the first mounting surface 60s1 of the support base 60A shown in Figures 1A to 1C, while the second mirror member 30b is held by the holding device.

[0064] The direction of the laser beam L can be adjusted by rotating the second mirror member 30b around the X or Y axis to change its orientation. By rotating the second mirror member 30b around the X axis, the direction of the laser beam L can be changed vertically. By rotating the second mirror member 30b around the Y axis, the direction of the laser beam L can be changed horizontally, with the forward direction being the forward direction.

[0065] Furthermore, the height of the optical axis of the laser beam L can be adjusted by changing the position of the second reflective surface 30bs of the second mirror member 30b in the Z direction. By shifting the second reflective surface 30bs of the second mirror member 30b along the +Z direction, the height of the optical axis of the laser beam L can be reduced, and by shifting the second mirror member 30b along the -Z direction, the height of the optical axis of the laser beam L can be increased.

[0066] The larger the dimension from the top edge to the bottom edge of the second reflective surface 30bs, the wider the range over which the height of the optical axis of the laser beam L reflected by the second reflective surface 30bs can be adjusted. In the example shown in Figure 1B, the top edge of the second reflective surface 30bs is located above the point where the optical axis of the laser beam L strikes the reflective surface 94s of the mirror member 94 furthest from the focusing lens 70 in the X direction. The bottom edge of the second reflective surface 30bs is located below the point where the optical axis of the laser beam L strikes the reflective surface 94s of the mirror member 94 closest to the focusing lens 70 in the X direction.

[0067] If the dimension from the top edge to the bottom edge of the second reflective surface 30bs is large, then widening the bottom surface of the second mirror member 30b allows the second mirror member 30b to be stably positioned on the top surface 50us of the cover 50. The dimension of the bottom surface of the second mirror member 30b in the X direction may be, for example, 0.8 to 1.2 times the dimension of the top surface 50us of the cover 50 in the X direction. The dimension of the bottom surface of the second mirror member 30b in the Z direction may be, for example, 0.3 to 0.8 times the dimension of the top surface 50us of the cover 50 in the Z direction. Since a second mirror member 30b of such a large size is easy to hold with a holding device, it is easy to position the second mirror member 30b in the appropriate position and orientation.

[0068] Furthermore, while the multiple second mirror members 30b may have the same shape externally, they may also have multiple second reflective surfaces 30bs at different positions. In this case, the second reflective surfaces 30bs are located inside the second mirror members 30b, and the portion of the second mirror members 30b located in front of the second reflective surfaces 30bs may be translucent to the laser light L. With such multiple second mirror members 30b, even if the multiple second mirror members 30b are arranged at the same position in the +Z direction along the +X direction, the multiple second reflective surfaces 30bs can be shifted in steps along the +X direction and in the +Z direction.

[0069] Here, unlike Embodiment 1, we will take an example of a configuration in which the second mirror member 30b is fixed to the upper surface 50us of the cover 50 without adjusting its position and orientation. Even with such a configuration, in the light-emitting module 200 shown in Figures 1A to 1C, by arranging a wedge between the second mirror member 30b and the slow-axis collimating lens 92, the direction of propagation of the laser light L reflected by the second reflective surface 30bs can be directed in the +Z direction. The wedge has an incident light surface and a reflected light surface located on opposite sides of each other. The normal direction of the incident light surface is parallel to the -Z direction, and the normal direction of the emitted light surface is parallel to the YZ plane, forming an acute angle with the +Y direction or the -Y direction, and also forming an acute angle with the +Z direction. Due to the refraction at the incident light surface and the fact that they are not parallel to each other, the wedge can change the direction of propagation of the laser light L that passes through it. However, when using wedges, in order to direct the laser beam L in the +Z direction, it is necessary to prepare multiple wedges with different normal directions for the light-emitting surface, and select a wedge from among these wedges whose normal direction for the light-emitting surface is in the appropriate direction.

[0070] In contrast, in Embodiment 1, by arranging the second mirror member 30b in an appropriate position and orientation, the direction of propagation of the laser beam L reflected by the second reflective surface 30bs can be directed in the +Z direction, regardless of whether the direction of propagation of the laser beam L emitted from the laser light source 20 is deviated from the +Z direction. In Embodiment 1, it is not necessary to prepare a plurality of second mirror members 30b with different angles between their top surface and slanted surface, and to select a second mirror member 30b with an appropriate angle from among these plurality of second mirror members 30b.

[0071] In this specification, the mirror member 94 shown in Figures 1A to 1C will also be referred to as the "third mirror member," and the reflective surface 94s shown in Figures 1A to 1C will also be referred to as the "third reflective surface." The third reflective surface 94s reflects the laser light reflected by the second reflective surface 30bs in the +X direction.

[0072] The mirror members 30a and 30b shown in Figures 2C and 2D, the mirror member 94 shown in Figures 1A to 1C, and the mirror members 94a to 94c shown in Figure 1D may comprise, for example, a base having an inclined surface and a reflective surface separately formed on the inclined surface. The base may be formed from at least one selected from the group consisting of, for example, glass, quartz, synthetic quartz, sapphire, ceramics, plastic, silicon, metal, silicone resin, and dielectric materials. The reflective surface may be formed from a reflective material such as a dielectric multilayer film and a metallic material. This reflective surface corresponds to the reflective surfaces 30as and 30bs shown in Figure 2C, the reflective surface 94s shown in Figure 1A, and the reflective surfaces 94as to 94cs shown in Figure 1D.

[0073] Alternatively, the first mirror member 30a, the second mirror member 30b, and the mirror members 94, 94a to 94c may each include, for example, a base having an inclined surface, and the base may be formed from the reflective material described above. In this case, the inclined surface of the base corresponds to the first reflective surface 30as, the second reflective surface 30bs, and the reflective surfaces 94s, 94as to 94cs.

[0074] <Frame 40> The frame 40 is positioned around the mounting surface 10us of the substrate 10, as shown in Figure 2C, and supports the cover 50, as shown in Figure 2B. The frame 40 surrounds the laser light source 20 and the first mirror member 30a when viewed from the +Y direction, i.e., from above, as shown in Figure 2C. The frame 40 has protrusions 40p that project inward from the inner surface, as shown in Figure 2D. In the example shown in Figure 2F, the protrusions 40p project toward both sides and the back of the submount 21. The protrusions 40p may also project toward the front of the submount 21. Alternatively, the protrusions 40p may project only toward both sides. The front of the submount 21 is located on the same side as the emission surface of the semiconductor laser element 22, and the back of the submount 21 is located on the opposite side from the emission surface of the semiconductor laser element 22. The two sides of the submount 21 connect the front and back of the submount 21.

[0075] As shown in Figure 2D, the frame 40 has a first upper surface 40us1 and a second upper surface 40us2. The second upper surface 40us2 is the upper surface of the protruding portion 40p, is located below the first upper surface 40us1, and is surrounded by the first upper surface 40us1 in a top view. As shown in Figure 2F, the second upper surface 40us2 has a roughly U-shape.

[0076] The first upper surface 40us1 is provided with a first bonding region 44a and an outer region 46 surrounding the first bonding region 44a. Each of the first bonding region 44a and the outer region 46 has a roughly rectangular annular shape. The first bonding region 44a improves the bonding strength when the cover 50 and the frame 40 are joined via an inorganic bonding member such as solder. The outer region 46 reduces the flow of the inorganic bonding member used to join the cover 50 beyond the outer region 46. As shown in Figure 2F, the first bonding region 44a and the outer region 46 surround the laser light source 20 and the first mirror member 30a in a top view. The first upper surface 40us1 is further provided with a first conductive region 42a and a second conductive region 42b that are electrically insulated from each other in the -Z direction from the first bonding region 44a and the outer region 46.

[0077] The second upper surface 40us2 is provided with a third conductive region 42c and a fourth conductive region 42d that are electrically insulated from each other. The third conductive region 42c is electrically connected to the first conductive region 42a via internal wiring, and the fourth conductive region 42d is electrically connected to the second conductive region 42b via internal wiring. As shown in Figure 2F, in a top view, the laser light source 20 and the first mirror member 30a are located between the portion of the third conductive region 42c extending in the Z direction and the portion of the fourth conductive region 42d extending in the Z direction. The third conductive region 42c is electrically connected to the semiconductor laser element 22 via the upper surface of the submount 21 and some wires 40w shown in Figure 2C. The fourth conductive region 42d is electrically connected to the semiconductor laser element 22 via the remaining wires 40w shown in Figure 2C. Therefore, the laser light source 20 can be powered by applying a voltage between the first conductive region 42a and the second conductive region 42b.

[0078] The frame 40 further has a first lower surface 40Ls1 and a second lower surface 40Ls2, as shown in Figure 2E. The second lower surface 40Ls2 partially has the lower surface of the protrusion 40p, is located above the first lower surface 40Ls1, and is surrounded by the first lower surface 40Ls1 when viewed from the -Y direction, i.e., from below. The second lower surface 40Ls2 has a roughly rectangular annular shape. Part or all of the substrate 10 shown in Figure 2D is housed in the space enclosed by the step between the first lower surface 40Ls1 and the second lower surface 40Ls2. When viewed through the frame 40, the outer circumference of the second lower surface 40Ls2 surrounds the outer circumference of the mounting surface 10us of the substrate 10 when viewed from above, and the inner circumference of the second lower surface 40Ls2 surrounds the outer circumference of the mounting surface 10us of the substrate 10 when viewed from above.

[0079] A second bonding region 44b is provided across the entire first lower surface 40Ls1. The second bonding region 44b improves the bonding strength when the support base 60A and frame 40 shown in Figures 1A to 1C are joined via an inorganic bonding member such as solder. A third bonding region 44c is provided across the entire second lower surface 40Ls2. The third bonding region 44c is joined to the peripheral region of the mounting surface 10us of the substrate 10 via an inorganic bonding member such as brazing material. The third bonding region 44c improves the bonding strength when the substrate 10 and frame 40 are joined via an inorganic bonding member. The melting point of brazing material is higher than that of solder. Therefore, when the brazing material is heated to bond the substrate 10 and frame 40, and then the solder is heated to bond the substrate 10 and laser light source 20, the possibility of the bond between the substrate 10 and frame 40 coming undone due to the heat applied to the solder can be reduced.

[0080] In the example shown in Figure 2E, the second bonding region 44b is provided over the entire first lower surface 40Ls1, but the second bonding region 44b may be provided only on a part of the first lower surface 40Ls1. Similarly, in the example shown in Figure 2E, the third bonding region 44c is provided over the entire second lower surface 40Ls2, but the third bonding region 44c may be provided only on a part of the second lower surface 40Ls2. Furthermore, the second bonding region 44b may not be provided on the first lower surface 40Ls1, and the third bonding region 44c may not be provided on the second lower surface 40Ls2. If the second bonding region 44b is not provided on the first lower surface 40Ls1, the frame 40 and the support base 60A are not bonded, and the substrate 10 and the support base 60A are bonded only at the lower surface 10Ls of the substrate 10.

[0081] In the example shown in Figure 2G, the first lower surface 40Ls1 of the frame 40 is located on the same plane as the lower surface 10Ls of the substrate 10. The first lower surface 40Ls1 of the frame 40 may be located above the lower surface 10Ls of the substrate 10. Alternatively, the first lower surface 40Ls1 of the frame 40 may be located below the lower surface 10Ls of the substrate 10, as long as it does not interfere with joining the substrate 10 and the support base 60A via an inorganic bonding member.

[0082] The frame 40 may be formed from the aforementioned ceramics, for example, similar to the support base 60A shown in Figures 1A to 1C. The dimensions of the frame 40 in the X direction may be, for example, 3 mm to 15 mm, the maximum dimensions in the Y direction may be, for example, 1 mm to 5 mm, and the dimensions in the Z direction may be, for example, 3 mm to 30 mm.

[0083] The conductive regions 42a to 42d, the bonding regions 44a to 44c, and the outer region 46 may be formed from, for example, at least one metallic material selected from the group consisting of Ag, Cu, W, Au, Ni, Pt, and Pd. The conductive regions 42a to 42d, the bonding region 44a, and the outer region 46 may be formed, for example, by providing a metal film over the entire upper surfaces 40us1 and 40us2 and patterning the metal film by etching.

[0084] <Cover 50> As shown in Figure 2C, the cover 50 has an upper surface 50us and a lower surface 50Ls. The lower surface 50Ls of the cover 50 faces the mounting surface 10us of the substrate 10, and the upper surface 50us of the cover 50 is located on the opposite side of the lower surface 50Ls of the cover 50. In this specification, the lower surface 50Ls of the cover 50 is also referred to as the "facing surface". The cover 50 is located above the semiconductor laser element 22 and the first mirror member 30a. The cover 50 transmits the laser light L reflected by the first reflective surface 30as.

[0085] The cover 50 has a light-shielding film 52 around at least the light-transmitting region 50t that transmits laser light L on the lower surface 50Ls. In the example shown in Figure 2D, the light-transmitting region 50t has a rectangular shape, but is not limited to this shape. The shape of the light-transmitting region 50t may be, for example, circular or elliptical. Alternatively, the cover 50 may have a light-shielding film 52 around at least a portion of the periphery of the light-transmitting region 50t on the lower surface 50Ls. For example, if a portion of the edge of the light-transmitting region 50t coincides with a portion of the edge of the lower surface 50Ls, the light-shielding film 52 may be provided on at least a portion of the following region on the lower surface 50Ls. This region is the region on the lower surface 50Ls adjacent to the remaining portion of the edge of the light-transmitting region 50t other than the portion mentioned above.

[0086] The light-shielding film 52 reduces the possibility of stray light other than the laser light L generated inside the light-emitting device 100A leaking to the outside of the light-emitting device 100A. Furthermore, the light-shielding film 52 reduces the possibility of ultraviolet or visible light reaching the laser light source 20 when the resin layer 32 shown in Figure 2G is formed by irradiation with ultraviolet or visible light. Furthermore, the light-shielding film 52 reduces the possibility of reflected light from the laser light L emitted outside the light-emitting device 100A reaching the laser light source 20. If irradiation by ultraviolet or visible light or reflected light can be reduced, the laser light source 20 will be less likely to be damaged.

[0087] In the example shown in Figure 2D, the light-shielding film 52 is provided on the entire area of ​​the lower surface 50Ls, excluding the light-transmitting region 50t. The light-shielding film 52 provided in this manner further reduces the possibility of stray light leaking outside the light-emitting device 100A, and the possibility of ultraviolet light, visible light, or reflected light reaching the laser light source 20.

[0088] Of the cover 50, not only the light-transmitting region 50t but also the portion that overlaps with the light-transmitting region 50t in a top view transmits the laser light L. The portion of the cover 50 that transmits the laser light L has a transmittance of, for example, 60% or more, and preferably 80% or more, with respect to the laser light L. The remaining portion of the cover 50 may or may not have such light transmittance.

[0089] The cover 50 may be formed from the aforementioned translucent material, for example, similar to the focusing lens 70 shown in Figures 1A and 1B. The dimensions of the cover 50 in the X direction may be, for example, 3 mm to 15 mm, the dimensions in the Y direction may be, for example, 0.1 mm to 1.5 mm, and the dimensions in the Z direction may be, for example, 1 mm to 20 mm.

[0090] The light-shielding film 52 can be formed from the aforementioned metal material, for example, the conductive regions 42a to 42d, the bonding regions 44a to 44c, and the outer region 46. The light-shielding film 52 can be formed, for example, by applying a metal film to the entire lower surface 50Ls of the cover 50, and then patterning the metal film by etching, for example, the conductive regions 42a to 42d, the bonding region 44a, and the outer region 46.

[0091] The peripheral region of the light-shielding film 52 is joined to a first joining region 44a provided on the first upper surface 40us1 of the frame 40 via an inorganic joining member such as solder. When the light-shielding film 52 is formed from the above-mentioned metal material, the light-shielding film 52 improves the joining strength when the cover 50 and the frame 40 are joined via the inorganic joining member.

[0092] In the examples shown in Figures 2A to 2G, the cover 50 has a flat plate shape, but is not limited to this shape. In a configuration where the substrate 10 has a flat plate shape without a frame 40, the cover 50 may have a box shape with an open bottom instead of a flat plate shape. A cover 50 having such a shape is supported by the mounting surface 10us of the substrate 10 and houses the laser light source 20 and the first mirror member 30a. Alternatively, the cover 50 having an open bottom box shape may be joined to the frame 40, and the laser light source 20 and the first mirror member 30a may be surrounded by the cover 50 and the frame 40.

[0093] From the above, according to Embodiment 1, it is possible to realize a light-emitting device 100A that can reduce the deviation between the direction of propagation of the laser beam L and the design direction of propagation. Furthermore, even if multiple light-emitting devices 100A are arranged on the same plane, by making the positions of the second reflective surfaces 30bs of the multiple second mirror members 30b in the Z direction different from each other, the heights of the optical axes of the laser beam L emitted from the multiple light-emitting devices 100A can be made different from each other. With the above-mentioned same plane as a reference, the height of the intersection point between the second reflective surface 30bs and the optical axis of the laser beam L differs depending on the position of the second reflective surfaces 30bs of the multiple second mirror members 30b in the +Z direction. By employing such a light-emitting device 100A in the light-emitting module 200 shown in Figures 1A to 1C, multiple laser beams L obtained by emitting laser beams L from each of the multiple light-emitting devices 100A can be effectively combined and incident into the optical fiber 80.

[0094] In the light-emitting module 200, two or more light-emitting devices 100A are arranged along the X direction on the same plane. Alternatively, the number of light-emitting devices 100A may be increased by arranging two or more light-emitting devices 100A on each of multiple planes that are at different heights and aligned along the X direction.

[0095] The light-emitting device 100A can be manufactured, for example, as follows. In the first step, a substrate 10, a laser light source 20, a first mirror member 30a, a second mirror member 30b, a frame 40, a plurality of wires 40w, and a cover 50 are prepared. In the next step, the frame 40 is bonded to the substrate 10. In the next step, the laser light source 20 and the first mirror member 30a are placed on the mounting surface 10us of the substrate 10. In the next step, a plurality of wires 40w for supplying power to the laser light source 20 are provided. In the next step, the cover 50 is bonded to the frame 40. In the next step, active alignment is performed with the lower surface of the second mirror member 30b in contact with the upper surface 50us of the cover 50 via uncured resin. In the next step, the resin is cured to form a resin layer 32 between the second mirror member 30b and the cover 50.

[0096] (Embodiment 2) In the light-emitting device 100A according to Embodiment 1, the semiconductor laser element 22 is sealed by a substrate 10, a frame 40, and a cover 50, the first mirror member 30a is located inside the space in which the semiconductor laser element 22 is sealed, and the second mirror member 30b is located outside the space. However, the first mirror member 30a does not need to be located inside the space.

[0097] The configuration example of a light-emitting device according to Embodiment 2 of this disclosure will be described below with reference to Figures 3A to 3D. In the light-emitting module 200 shown in Figures 1A to 1C, the light-emitting device according to Embodiment 2 may be used instead of the light-emitting device 100A according to Embodiment 1. In the light-emitting device according to Embodiment 2, the semiconductor laser element 22 is sealed by a package, the first mirror member 30a is located outside the space in which the semiconductor laser element 22 is sealed, and the second mirror member 30b is located outside the said space.

[0098] Figure 3A is a schematic perspective view showing an example of the configuration of a light-emitting device according to exemplary embodiment 2 of the present disclosure. Figure 3B is a schematic perspective view showing another example of the configuration of a light-emitting device according to exemplary embodiment 2 of the present disclosure. The light-emitting device 100B shown in Figures 3A and 3B comprises a laser light source 20P, a first mirror member 30a, a second mirror member 30b, and a support 40S that supports these components. Figure 3C is a cross-sectional view of the light-emitting device 100B shown in Figure 3B, parallel to the YZ plane. Figure 3D is a schematic perspective view showing the configuration of the support 40S included in the light-emitting device 100B shown in Figures 3A and 3B. The support 40S has a first support surface 40Ss1 that supports the first mirror member 30a, a second support surface 40Ss2 that supports the second mirror member 30b, and a third support surface 40Ss3 that supports the laser light source 20P.

[0099] The laser light source 20P emits laser light L in approximately the +Z direction. The direction of propagation of the laser light L emitted from the laser light source 20P may not be perfectly parallel to the design direction of propagation, which is the +Z direction. As will be explained in detail later, in the light-emitting device 100B according to Embodiment 2, regardless of whether the direction of propagation of the laser light L emitted from the laser light source 20P is deviated from the +Z direction, the direction of propagation of the laser light L can be directed to the design direction of propagation, which is the +Z direction, by reflecting the laser light L emitted from the laser light source 20P in the order of the first reflecting surface 30as and the second reflecting surface 30bs, as shown in Figure 3C.

[0100] Furthermore, in the light-emitting device 100B according to Embodiment 2, as shown in Figures 3A and 3B, the height of the optical axis of the laser beam L reflected by the second reflective surface 30bs of the second mirror member 30b decreases as it is shifted along the +Z direction. Therefore, even if multiple light-emitting devices 100B are arranged on the same plane, the heights of the optical axes of the laser beams emitted from the multiple light-emitting devices 100B can be made to differ from one another.

[0101] The following describes each component of the light-emitting device 100B.

[0102] <Laser light source 20P> As shown in Figure 3C, the laser light source 20P comprises a submount 21, a semiconductor laser element 22, a lens support member 23, a velocity-axis collimating lens 24, and a package that encloses these components. The configuration comprising the submount 21, semiconductor laser element 22, lens support member 23, and velocity-axis collimating lens 24 is as described in Embodiment 1. The laser light source 20P emits laser light L from the semiconductor laser element 22, which is collimated in the YZ plane by the velocity-axis collimating lens 24, and emits it approximately in the +Z direction. The specific configuration of the laser light source 20P will be described later.

[0103] In reality, the direction of propagation of the laser beam L emitted from the laser light source 20P may be deviated from the +Z direction. The angle between the direction of propagation of the laser beam L emitted from the laser light source 20P and the +Z direction may be, for example, 10° or less.

[0104] <First mirror member 30a and second mirror member 30b> The first mirror member 30a and the second mirror member 30b are as described in the light-emitting device 100A according to Embodiment 1. However, in the light-emitting device 100B according to Embodiment 2, the cross-sectional shape of the first mirror member 30a is roughly trapezoidal rather than roughly triangular.

[0105] As shown in Figure 3C, the first reflective surface 30as reflects the laser beam L emitted from the laser light source 20P, changing the direction of the laser beam L away from the first support surface 40Ss1 of the support 40S. It can also be said that the first reflective surface 30as reflects the laser beam L, changing the direction of the laser beam L away from the first mounting surface 60s1 shown in Figures 1A to 1C. The angle between the direction in which the laser beam L moves away from the first support surface 40Ss1 or the first mounting surface 60s1 of the support 40S and the normal direction of the mounting surface 10us may be, for example, 0° or more and 5° or less. Since there is a tolerance of 5° for this angle, it is not necessary to adjust the position and orientation of the first mirror member 30a as precisely as the position and orientation of the second mirror member 30b.

[0106] The second mirror member 30b has a second reflective surface 30bs on the inclined surface described above. At least a portion of the second reflective surface 30bs is located above at least a portion of the first reflective surface 30as. As shown in Figure 3C, the second reflective surface 30bs reflects the laser light L reflected by the first reflective surface 30as, changing the direction of propagation of the laser light L in the +Z direction. The adjustment of the position and orientation of the second mirror member 30b will be described later.

[0107] As shown in Figures 3A and 3B, the more the second mirror member 30b shifts in the +Z direction and approaches the first mirror member 30a, the smaller the height of the optical axis of the laser beam L reflected by the second reflective surface 30bs becomes. As described in Embodiment 1, the larger the dimension from the top edge to the bottom edge of the second reflective surface 30bs, the wider the range over which the height of the optical axis of the laser beam L reflected by the second reflective surface 30bs can be adjusted.

[0108] Here, unlike Embodiment 2, the direction of propagation of the laser beam L emitted from the laser light source 20P can also be directed in the +Z direction by arranging the wedges described in Embodiment 1 instead of the first mirror member 30a and the second mirror member 30b. However, when using wedges, in order to direct the direction of propagation of the laser beam L in the +Z direction, it is necessary to prepare a plurality of wedges whose normal directions of the light-emitting surface are different from each other, and to select a wedge from among these plurality of wedges whose normal direction of the light-emitting surface is in an appropriate direction.

[0109] In contrast, in Embodiment 2, by arranging the second mirror member 30b in an appropriate position and orientation, the direction of propagation of the laser beam L emitted from the laser light source 20 can be directed in the +Z direction. Therefore, it is not necessary to prepare a plurality of second mirror members 30b with different angles between their top surface and inclined surface, and to select a second mirror member 30b with an appropriate angle from among these plurality of second mirror members 30b.

[0110] <Support 40S> As shown in Figures 3C and 3D, the support 40S has an upper surface 40Sus with irregularities and a lower surface 40SLs which is a plane parallel to the XZ plane. The support 40S has a recess 40Sc in the upper surface 40Sus. In the recess 40Sc, the support 40S has a notch 40Sn through which the laser beam L emitted from the laser light source 20P passes. The support 40S further has two wall portions 40Sw in the recess 40Sc that are located on both sides of the optical path of the laser beam L emitted from the laser light source 20P.

[0111] The support 40S has a first support surface 40Ss1 on its upper surface 40Sus, which is at least a part of the bottom surface of the recess 40Sc. The first support surface 40Ss1 is parallel to the XZ plane. The first support surface 40Ss1 supports the first mirror member 30a such that the first reflective surface 30as reflects the laser beam L, changing the direction of propagation of the laser beam L away from the support 40S. A part of the first mirror member 30a is located between two wall portions 40Sw. The lower surface of the first mirror member 30a is joined to the first support surface 40Ss1. A bonding resin layer exists between the first support surface 40Ss1 and the lower surface of the first mirror member 30a. The thickness of the resin layer (dimension in the Y direction) may be, for example, 0.005 mm or more and 0.5 mm or less. The heat generated in the first mirror member 30a by irradiation with laser light L during operation can be effectively transferred to the support 40S via the first support surface 40Ss1 that supports the first mirror member 30a. If the thickness of the resin layer (dimension in the Y direction) is within the above range, the resin layer does not significantly hinder the transfer of the heat to the support 40S. The same applies to the resin layer described below.

[0112] The support 40S has a second support surface 40Ss2 on its upper surface 40Sus, which is at least a portion of the upper surfaces of the two wall portions 40Sw. The second support surface 40Ss2 is parallel to the XZ plane. The second support surface 40Ss2 supports the second mirror member 30b such that at least a portion of the second reflective surface 30bs is located above at least a portion of the first reflective surface 30as. The second support surface 40Ss2 further supports the second mirror member 30b such that the second reflective surface 30bs reflects the laser light L reflected by the first reflective surface 30as, thereby changing the direction of propagation of the laser light L in the +Z direction. In the example shown in Figure 3C, the second support surface 40Ss2 supports both ends of the second mirror member 30b. If the recess 40Sc has only one wall portion 40Sw instead of two wall portions 40Sw, the second support surface 40Ss2 supports one end of the second mirror member 30b. A portion of the lower surface of the second mirror member 30b, specifically the lower surface of one or both ends of the second mirror member 30b, is joined to the second support surface 40Ss2. A bonding resin layer 32 exists between the second support surface 40Ss2 and a portion of the lower surface of the second mirror member 30b. The second mirror member 30b is adjusted to an appropriate position and orientation by bringing a portion of the lower surface of the second mirror member 30b into contact with the second support surface 40Ss2 via the uncured resin, so that the second reflective surface 30bs changes the direction of propagation of the laser beam L in the +Z direction. Active alignment, as described in Embodiment 1, is performed in adjusting the position and orientation of the second mirror member 30b. After that, the resin is cured to form the resin layer 32. The adjustment of the position and orientation of the second mirror member 30b can be performed after placing the light-emitting device 100B on the first mounting surface 60s1 of the support base 60A shown in Figures 1A to 1C, while holding the second mirror member 30b with a holding device. The heat generated in the second mirror member 30b by the irradiation of the laser light L during operation can be effectively transferred to the support 40S via the second support surface 40Ss2 that supports the second mirror member 30b.

[0113] A plane parallel to the XZ plane, which is located on the opposite side of the surface on which the first mirror member 30a and the second mirror member 30b are mounted when viewed from the support 40S, is used as the height reference plane for the light-emitting device 100B. This reference plane may be, for example, the lower surface 40SLs of the support 40S shown in Figures 3C and 3D. The "height" described below is the height from this reference plane. The height of the second support surface 40Ss2 is greater than the height of the first support surface 40Ss1. The second mirror member 30b, supported by the second support surface 40Ss2, is located above the optical path of the laser beam L emitted from the laser light source 20P and does not obstruct the propagation of the laser beam L.

[0114] Unlike the light-emitting device 100B according to Embodiment 2, in a configuration where the height of the second support surface 40Ss2 is equal to the height of the first support surface 40Ss1, the second mirror member 30b is required to have a complex shape that straddles the optical path of the laser beam L emitted from the laser light source 20P so as not to obstruct the propagation of the laser beam L. In contrast, in the light-emitting device 100B according to Embodiment 2, since the height of the second support surface 40Ss2 is greater than the height of the first support surface 40Ss1, the second mirror member 30b does not need to have such a complex shape. The second mirror member 30b may have a simple shape with a flat bottom surface.

[0115] The first support surface 40Ss1 and the second support surface 40Ss2 are planes parallel to each other. Therefore, if the angle between the upper surface and the inclined surface of the second mirror member 30b is equal to the angle between the lower surface and the inclined surface of the first mirror member 30a, then when a portion of the lower surface of the second mirror member 30b is brought into contact with the second support surface 40Ss2 via the uncured resin, the second reflective surface 30bs becomes approximately parallel to the first reflective surface 30as. From this state, the position and orientation of the second mirror member 30b can be finely adjusted, making it easier to position the second mirror member 30b in the appropriate position and orientation.

[0116] The first reflective surface 30as and the second reflective surface 30bs are located apart from each other, and a gas such as air is present between the first reflective surface 30as and the second reflective surface 30bs. As the laser beam L travels from the first reflective surface 30as to the second reflective surface 30bs, it does not enter the resin layer 32 located between the second mirror member 30b and the second support surface 40Ss2, thus reducing the deterioration of the resin layer 32. The distance in the Z direction from the first reflective surface 30as to the second reflective surface 30bs may be, for example, 0.1 mm or more and 3 mm or less.

[0117] The dimension of the second reflective surface 30bs in the X direction is greater than the maximum distance between the two wall portions 40Sw, and the dimension of the first reflective surface 30as in the X direction is smaller than the said maximum distance. Therefore, the dimension of the second reflective surface 30bs in the X direction is greater than the dimension of the first reflective surface 30as in the X direction. The dimension of the second reflective surface 30bs in the X direction may be, for example, between 1.1 and 4 times the dimension of the first reflective surface 30as in the X direction. Since the second reflective surface 30bs has such dimensions, it is susceptible to receiving laser light L whose width in the X direction widens as it travels from the first reflective surface 30as to the second reflective surface 30bs.

[0118] A portion of the laser light L reflected by the first reflective surface 30as and / or the second reflective surface 30bs may become stray light, and this stray light may spread as it propagates. Even in this case, if the distance between the two wall portions 40Sw in the X direction is narrow, the incidence of stray light as reflected light into the laser light source 20P can be reduced. The distance between the two wall portions 40Sw in the X direction may be, for example, 0.1 mm or more and 3 mm or less. If the distance is within this range, the incidence of stray light as reflected light into the laser light source 20P can be adequately reduced. Furthermore, if the height of the wall portion 40Sw (dimension in the Y direction) is large, stray light generated at the first reflective surface 30as can be prevented from entering the resin layer 32 located between the second mirror member 30b and the second support surface 40Ss2, thereby reducing the deterioration of the resin layer 32. The height of the wall portion 40Sw may be, for example, 0.1 mm or more and 5 mm or less. If the height is within this range, such stray light can be effectively prevented from entering the resin layer. Furthermore, since stray light generated at the second reflective surface 30bs often propagates away from the resin layer, the possibility of such stray light incident on the resin layer 32 is low.

[0119] The support 40S further has a third support surface 40Ss3 located outside the recess 40Sc on its upper surface 40Sus. The third support surface 40Ss3 is parallel to the XZ plane. The third support surface 40Ss3 supports the laser light source 20P. An inorganic bonding layer for bonding exists between the third support surface 40Ss3 and the lower surface of the laser light source 20P. Heat generated in the laser light source 20P during operation can be effectively transferred to the support 40S via the third support surface 40Ss3. Since the height of the third support surface 40Ss3 is smaller than the height of the first support surface 40Ss1, the laser light source 20P supported by the third support surface 40Ss3 can easily direct the laser beam L onto the first reflective surface 30as.

[0120] The support 40S may be formed from the same material as the support base 60A shown in Figures 1A to 1C. In this case, the support 40S can effectively transfer to the support base 60A the heat emitted from the laser light source 20P during operation, and the heat generated in the first mirror member 30a and the second mirror member 30b by irradiation with laser light L. The support 40S may also be formed integrally with the support base 60A. In this case, the support 40S corresponds to a part of the support base 60A.

[0121] From the above, according to Embodiment 2, a light-emitting device 100B can be realized that can reduce the deviation between the direction of propagation of the laser beam L and the design direction of propagation. Furthermore, even if multiple light-emitting devices 100A are arranged on the same plane, the heights of the optical axes of the laser beam L emitted from multiple light-emitting devices 100B can be made to differ from each other by making the positions of the second reflective surfaces 30bs of the multiple second mirror members 30b in the Z direction different from each other. With respect to the above-mentioned same plane, the height of the intersection point between the second reflective surface 30bs and the optical axis of the laser beam L differs depending on the position of the second reflective surfaces 30bs of the multiple second mirror members 30b in the +Z direction. By employing such a light-emitting device 100B in the light-emitting module 200 shown in Figures 1A to 1C, multiple laser beams L obtained by emitting laser beams L from each of the multiple light-emitting devices 100B can be effectively combined and incident into the optical fiber 80.

[0122] The light-emitting device 100B can be manufactured, for example, as follows: In the first step, a laser light source 20P, a first mirror member 30a, a second mirror member 30b, and a support 40S are prepared. In the next step, the laser light source 20P is joined to the third support surface 40Ss3 of the support 40S. In the next step, the first mirror member 30a is joined to the first support surface 40Ss1 of the support 40S. In the next step, active alignment is performed with the lower surface of the second mirror member 30b in contact with the second support surface 40Ss2 of the support 40S via the uncured resin. In the next step, the resin is cured to form a resin layer 32 between the second mirror member 30b and the support 40S.

[0123] (Embodiment 3) Next, with reference to Figure 4, an example of the configuration of a DDL apparatus according to Embodiment 3 of the present disclosure will be described. Figure 4 is a schematic diagram showing the configuration of a DDL apparatus according to an exemplary Embodiment 3 of the present disclosure. The DDL apparatus 1000 shown in Figure 4 comprises a plurality of light-emitting modules 200 according to Embodiment 1, a processing head 300, and optical transmission fibers 250 connecting the light-emitting modules 200 to the processing head 300. In the example shown in Figure 4, the number of light-emitting modules 200 is four, but is not limited to this number. The number of light-emitting modules 200 may be one, two, three, or five or more.

[0124] The number of light-emitting devices 100A included in each light-emitting module 200 is determined according to the required light output or irradiance. The wavelength of the laser light emitted from the light-emitting devices 100A can also be selected according to the material to be processed. For example, when processing metals such as copper, brass, and aluminum, semiconductor laser elements with a central wavelength in the range of 350 nm to 550 nm can be suitably used. The wavelengths of the laser light emitted from each light-emitting device 100A do not need to be the same; laser light with different central wavelengths may be superimposed. Furthermore, it is possible to obtain the effects of the present invention even when using laser light with a central wavelength outside the range of 350 nm to 550 nm.

[0125] In the example shown in Figure 4, an optical fiber 80 extends from each of the multiple light-emitting modules 200. These multiple optical fibers 80 are then coupled to an optical transmission fiber 250 by an optical multiplexer 230. The optical multiplexer 230 may be, for example, a TFB (Tapered Fiber Bundle). The processing head 300 focuses the laser light emitted from the optical output end of the optical fiber 80 onto the object 400. When one DDL device 1000 is equipped with M light-emitting modules 200, and each light-emitting module 200 is equipped with N light-emitting devices 100A, if the optical output of one light-emitting device 100A is P watts, then a laser beam with a maximum optical output of P × N × M watts can be focused onto the object 400. Here, N is an integer greater than or equal to 2, and M is a positive integer. For example, if P = 20 watts, N = 22, and M = 12, an optical output of more than 5 kilowatts can be achieved.

[0126] (Configuration of the laser light source 20) Next, with reference to Figures 5A and 5B, an example of the configuration of the laser light source 20 included in the light-emitting device 100A according to Embodiment 1 will be described. Figure 5A is a schematic exploded perspective view showing an example of the configuration of the laser light source 20 included in the light-emitting device 100A according to Embodiment 1. Figure 5B is a cross-sectional view of the laser light source 20 shown in Figure 5A, parallel to the YZ plane. The individual components of the laser light source 20 will be described below.

[0127] As shown in Figure 5A, the submount 21 has an upper surface 21us and a lower surface 21Ls that are parallel to the XZ plane. A metal film is provided on each of the upper surface 21us and the lower surface 21Ls. The metal film provided on the upper surface 21us improves the bonding strength when the semiconductor laser element 22 and the lens support member 23 are bonded to the submount 21 with an inorganic bonding member. The metal film provided on the upper surface 21us may also be used to supply power to the semiconductor laser element 22. The metal film provided on the lower surface 21Ls improves the bonding strength when the substrate 10 and the laser light source 20 shown in Figure 2C are bonded via an inorganic bonding member. The metal films provided on each of the upper surface 21us and the lower surface 21Ls also help to transfer the heat generated by the semiconductor laser element 22 during operation to the substrate 10 via the submount 21. The submount 21 may be formed from the aforementioned ceramic, metallic, or metal-matrix composite materials, similar to the support base 60A shown in Figures 1A to 1C.

[0128] The semiconductor laser element 22 is supported by the upper surface 21us of the submount 21, as shown in Figure 5A. The semiconductor laser element 22 has an emission surface 22e on one of two end faces that intersect in the Z direction, and emits laser light in the +Z direction from the emission surface 22e. The laser light spreads at different speeds in the YZ plane and the XZ plane as it propagates in the +Z direction. The laser light spreads relatively quickly in the YZ plane and relatively slowly in the XZ plane. The laser spot, when not collimated, is far-field and has an elliptical shape in the XY plane, with the Y direction being the major axis and the X direction being the minor axis.

[0129] The semiconductor laser element 22 can emit violet, blue, green, or red laser light in the visible region, or infrared or ultraviolet laser light in the invisible region. The emission peak wavelength of violet light is preferably in the range of 400 nm to 420 nm, and more preferably in the range of 400 nm to 415 nm. The emission peak wavelength of blue light is preferably greater than 420 nm and in the range of 495 nm or less, and more preferably in the range of 440 nm to 475 nm. The emission peak wavelength of green light is preferably greater than 495 nm and in the range of 570 nm or less, and more preferably in the range of 510 nm to 550 nm. The emission peak wavelength of red light is preferably in the range of 605 nm to 750 nm, and more preferably in the range of 610 nm to 700 nm.

[0130] Examples of semiconductor laser elements 22 that emit purple, blue, and green laser light include laser diodes containing nitride semiconductor materials. Examples of nitride semiconductor materials that can be used include GaN, InGaN, and AlGaN. Examples of semiconductor laser elements 22 that emit red laser light include laser diodes containing InAlGaP, GaInP, GaAs, and AlGaAs semiconductor materials.

[0131] As shown in Figure 5A, the lens support member 23 is supported by the upper surface 21us of the submount 21. The lens support member 23 has two columnar portions 23a and a connecting portion 23b located between the two columnar portions 23a and connecting them. The two columnar portions 23a are located on both sides of the semiconductor laser element 22, and the connecting portion 23b is located above the emission surface 22e side of the semiconductor laser element 22. The lens support member 23 supports the velocity collimating lens 24 by the end faces 23as of the two columnar portions 23a. The lens support member 23 is positioned to straddle the semiconductor laser element 22 and does not obstruct the laser light emitted from the semiconductor laser element 22 from entering the velocity collimating lens 24.

[0132] The lens support member 23 may be formed from the aforementioned ceramics, for example, similar to the support base 60A shown in Figures 1A to 1C. The lens support member 23 may be formed from the aforementioned translucent material, for example, similar to the focusing lens 70 shown in Figures 1A to 1C. The lens support member 23 may be formed from, for example, at least one alloy selected from the group consisting of Kovar and CuW. Kovar is an alloy in which nickel and cobalt are added to iron, which is the main component. The lens support member 23 may be formed from, for example, Si.

[0133] The velocity-axis collimating lens 24 may be a cylindrical lens having a uniform cross-sectional shape in the X direction, as shown in Figure 5A. The velocity-axis collimating lens 24 has a flat surface on the light incidence side and a convex curved surface on the light emission side. This convex curved surface has curvature in the YZ plane. The focal point of the velocity-axis collimating lens 24 approximately coincides with the center of the light emission point on the emission surface 22e of the semiconductor laser element 22. As shown in Figure 5B, the velocity-axis collimating lens 24 collimates the laser light emitted in the +Z direction from the emission surface 22e of the semiconductor laser element 22 in the YZ plane. The region enclosed by the dashed line in Figure 5B represents the laser light intensity at 1 / e of its peak intensity. 2 This represents a region where the value is more than double. e is the base of the natural logarithm. The velocity-axis collimating lens 24 can be formed from the aforementioned translucent material, for example, similar to the focusing lens 70 shown in Figures 1A to 1C.

[0134] As shown in Figure 2G, the velocity-axis collimating lens 24 is located between the mounting surface 10us of the substrate 10 and the lower surface 50Ls of the cover 50, and is positioned in the optical path of the laser beam L. Since the velocity-axis collimating lens 24 is located inside the sealing space formed by the substrate 10, the frame 40, and the cover 50, it can collide the laser beam L before it spreads out significantly. Therefore, it is possible to make the velocity-axis collimating lens 24 smaller.

[0135] Instead of the fast-axis collimating lens 24, a collimating lens that collimates the laser light L emitted from the semiconductor laser element 22 not only in the YZ plane but also in the XZ plane may be used. In that case, it is not necessary to provide the slow-axis collimating lenses 92, 92a, and 92b in the light-emitting module 200 shown in Figures 1A to 1C and the light-emitting module 210 shown in Figure 1D.

[0136] (20P laser light source configuration) Next, an example of the configuration of the laser light source 20P included in the light-emitting device 100B according to Embodiment 2 will be described with reference to Figures 6A and 6B. Figure 6A is a schematic perspective view showing an example of the configuration of the laser light source 20P included in the light-emitting device 100B according to Embodiment 2. The laser light source 20P shown in Figure 6A comprises the submount 21 shown in Figure 5A, a semiconductor laser element 22, a lens support member 23, and a velocity-axis collimating lens 24, and a base 20b that houses these components. The base 20b is provided with a light-transmitting window 20t that transmits the laser light L emitted from the semiconductor laser element 22. The laser light source 20P further comprises two lead terminals 25 that supply power to the laser light source 20, a lead holding member 20h that holds the two lead terminals 25, and a cover 20L fixed to the base 20b. The cover 20L, together with the base 20b, the lead holding member 20h, and the two lead terminals 25, forms a sealing space that seals the semiconductor laser element 22. As described in Embodiment 1, this sealing is preferably hermetically sealed. In this specification, the configuration comprising the base 20b, lead holding member 20h, two lead terminals 25, and cover 20L is also referred to as the "package".

[0137] Figure 6B is a schematic diagram showing the internal planar configuration of the laser light source 20P shown in Figure 6A. In Figure 6B, the cover 20L shown in Figure 6A is omitted. The base 20b includes a bottom plate 20b1, a stage 20b2 provided on the bottom plate 20b1, and a side wall 20b3 surrounding the stage 20b2. A light-transmitting window 20t shown in Figure 6A is provided in the side wall 20b3. It can also be said that the side wall 20b3 is equipped with the light-transmitting window 20t shown in Figure 6A. Inside the base 20b, the laser light source 20P includes a submount 21 supported by the stage 20b2, a semiconductor laser element 22 and a lens support member 23 supported by the submount 21, and a velocity-axis collimating lens 24 supported by the lens support member 23. The semiconductor laser element 22 is supported by a support 40S shown in Figures 3A and 3B via a bottom plate 20b1, a stage 20b2, and a submount 21. The configuration comprising the submount 21, the semiconductor laser element 22, the lens support member 23, and the velocity-axis collimating lens 24 has been described with reference to Figures 5A and 5B.

[0138] Of the base portion 20b, the bottom plate 20b1 and the stage 20b2 may be formed from a metallic material including, for example, at least one selected from the group consisting of Cu, Al, Ag, Fe, Ni, Mo, Cu, and W. Other examples of metallic materials include alloys such as CuMo. Since the bottom plate 20b1 and stage 20b2 formed from such metallic materials including alloys have high thermal conductivity, they can effectively transfer the heat emitted from the semiconductor laser element 22 to the outside during operation. Of the base portion 20b, the side walls 20b3 may be formed from, for example, Kovar.

[0139] The laser light source 20P further includes a plurality of wires 25w inside the base 20b. Of the plurality of wires 25w, some wires 25w are electrically connected to the semiconductor laser element 22 via a submount 21 and are electrically connected to one of the lead terminals 25. The remaining wires 25w are directly electrically connected to the semiconductor laser element 22 and are electrically connected to the other lead terminal 25. The plurality of wires 25w are used to supply power to the semiconductor laser element 22 from two lead terminals 25. The two lead terminals 25 are electrically connected to an external circuit that adjusts the emission timing and output of the laser light emitted from the semiconductor laser element 22.

[0140] Further details of the laser light source 20P are disclosed, for example, in Japanese Patent Publication No. 2021-106247. All disclosures of Japanese Patent Publication No. 2021-106247 are incorporated herein by reference.

[0141] This disclosure includes the light-emitting modules described in the following items. [Item 1] A support base having multiple mounting surfaces aligned in a first direction, A plurality of semiconductor laser elements, each of which emits laser light, wherein a corresponding semiconductor laser element is arranged on each of the plurality of mounting surfaces, A plurality of first mirror members, each having a first reflective surface, the first reflective surface reflecting the laser light and changing the direction of the laser light's propagation, A plurality of second mirror members, each having a second reflective surface, wherein at least a portion of the second reflective surface is located above at least a portion of the first reflective surface, and the plurality of second mirror members reflect the laser light reflected by the first reflective surface in a second direction intersecting the first direction. Equipped with, A light-emitting module in which the positions of the second reflective surfaces of the plurality of second mirror members in the second direction are different from each other. [Item 2] A plurality of third mirror members, each having a third reflective surface, the third reflective surface reflecting the laser light reflected by the second reflective surface in the first direction, The light-emitting module according to item 1, further comprising a focusing lens that couples a plurality of laser beams obtained by the reflection of the laser beam from the third reflective surface of each of the plurality of third mirror members into an optical fiber. [Item 3] The light-emitting module according to item 1 or 2, wherein the positions of the second reflective surfaces of the plurality of second mirror members in the second direction are steppedly different in the second direction along the first direction. [Item 4] The light-emitting module according to any one of items 1 to 3, wherein the first reflective surface reflects the laser light and changes the direction of propagation of the laser light away from the aforementioned mounting surface. [Item 5] The plurality of mounting surfaces are located on the same plane, and the light-emitting module device is as described in any one of items 1 to 4. [Item 6] The light-emitting module according to item 5, wherein the second direction is parallel to the coplane. [Item 7] The light-emitting module according to item 5 or 6, wherein, with reference to the aforementioned coplane, the height of the intersection point between the second reflective surface and the optical axis of the laser beam differs depending on the position of the second reflective surface of the plurality of second mirror members in the second direction. [Item 8] Each semiconductor laser element is sealed. The corresponding first mirror member is located inside the space in which each semiconductor laser element is sealed. The corresponding second mirror member is a light-emitting module according to any one of items 1 to 7, located outside the space. [Item 9] Each semiconductor laser element is sealed. The corresponding first mirror member is located outside the space in which each semiconductor laser element is sealed. The corresponding second mirror member is a light-emitting module according to any one of items 1 to 7, located outside the space. [Industrial applicability]

[0142] The light-emitting device of this disclosure can be used in particular to combine multiple laser beams to realize a high-power laser beam. Furthermore, the light-emitting device of this disclosure can be used, for example, in industrial fields where a high-power laser light source is required, such as cutting, drilling, localized heat treatment, surface treatment, metal welding, and 3D printing of various materials. [Explanation of Symbols]

[0143] 10: Substrate 10us: Mounting surface 10Ls: Bottom surface 20, 20P: Laser light source 20b: Base 20b1: Bottom plate 20b2: Stage 20b3: Side wall 20h: Lead holding member 20t: Translucent window 21: Submount 21Ls: Bottom surface 21us: Top surface 22: Semiconductor laser element 22e: Emission surface 23: Lens support member 23a: Columnar portion 23as: End face 23b: Connecting portion 24: Speed ​​axis collimating lens 25: Lead terminal 25w: Wire 30a: First mirror member 30as: First reflective surface 30b: Second mirror member 30bs: Second reflective surface 32: Resin layer 40: Frame 40us1: First top surface 40us2: Second top surface 40Ls1: First bottom surface 40Ls2: Second lower surface 40p: Projection 40w: Wire 42a: First conductive region 42b: Second conductive region 42c: Third conductive region 42d: Fourth conductive region 44a: First bonding region 44b: Second bonding region 44c: Third bonding region 46: Outer region 40S: Support body 40Sc: Recess 40Sn: Notch 40Ss1: First support surface 40Ss2: Second support surface 40Ss3: Third support surface 40Sus: Top surface 40SLs: Bottom surface 40Sw: Wall 50: Cover 50us: Top surface 50Ls: Bottom surface 50t: Transparent area 52: Light shielding film 60A, 62A: Support base 60A1, 62A1: 1st part 60A2, 62A2: Second part 60A3, 62A3: Third part 60s1: First mounting surface 60s2: Second mounting surface 60s3: Third mounting surface 70: Focusing lens 70a: Fast axis focusing lens 70b: Slow axis focusing lens 80: Optical fiber 80a: Optical incident end 80b: Optical exit end 82: Support member 92: Slow axis collimating lens 92a: Slow axis collimating lens 92b: Slow axis collimating lens 94, 94a, 94b, 94c: Mirror member 94s, 94as, 94bs, 94cs: Reflecting surface 96: Half wave plate 98: Polarizing beam splitter 100A, 100A1, 100A2, 100B: Light-emitting device 200, 210: Light-emitting module 230: Optical multiplexer 250: Optical transmission fiber 300: Processing head 400: Object 1000: DDL device

Claims

1. A support base having multiple mounting surfaces aligned in a first direction, A plurality of semiconductor laser elements, each of which emits laser light, wherein a corresponding semiconductor laser element is arranged on each of the plurality of mounting surfaces, A plurality of first mirror members, each having a first reflective surface, the first reflective surface reflecting the laser light and changing the direction of the laser light's propagation, A plurality of second mirror members, each having a second reflective surface, wherein at least a portion of the second reflective surface is located above at least a portion of the first reflective surface, and the plurality of second mirror members reflect the laser light reflected by the first reflective surface in a second direction intersecting the first direction, Equipped with, The positions of the second reflective surfaces of the plurality of second mirror members in the second direction are different from each other. The aforementioned multiple mounting surfaces are located on the same plane. A light-emitting module in which, with respect to the aforementioned coplane, the height of the intersection point between the second reflective surface and the optical axis of the laser beam is small enough that the position of the second reflective surface of the plurality of second mirror members in the second direction shifts in the second direction.

2. A plurality of third mirror members, each having a third reflective surface, the third reflective surface reflecting the laser light reflected by the second reflective surface in the first direction, The light-emitting module according to claim 1, further comprising a focusing lens that couples a plurality of laser beams obtained by the reflection of the laser beam from the third reflective surface of each of the plurality of third mirror members into an optical fiber.

3. The light-emitting module according to claim 1 or 2, wherein the positions of the second reflective surfaces of the plurality of second mirror members in the second direction are steppedly different in the second direction along the first direction.

4. The light-emitting module according to claim 1 or 2, wherein the first reflective surface reflects the laser light and changes the direction of propagation of the laser light toward the surface described above.

5. The light-emitting module according to claim 1 or 2, wherein the second direction is parallel to the coplane.

6. Each semiconductor laser element is sealed. The corresponding first mirror member is located inside the space in which each semiconductor laser element is sealed. The light-emitting module according to claim 1 or 2, wherein the corresponding second mirror member is located outside the space.

7. Each semiconductor laser element is sealed. The corresponding first mirror member is located outside the space in which each semiconductor laser element is sealed. The light-emitting module according to claim 1 or 2, wherein the corresponding second mirror member is located outside the space.

8. The light-emitting module according to claim 1 or 2, wherein each of the plurality of second mirror members has a single reflective surface, and the single reflective surface is the second reflective surface.

9. The light-emitting module according to claim 1 or 2, wherein the laser light does not pass through the interior of each of the plurality of second mirror members.

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