Light-emitting module

Abstract

A light-emitting module according to the present invention comprises: a support substrate which has a plurality of placement surfaces that are arranged in a first direction and that have heights decreasing along the first direction; a plurality of first laser light sources, one or more of which are disposed on each placement surface and which each emit, in a second direction, a first laser beam in a first peak wavelength range; a plurality of second laser light sources, one or more of which are disposed on each placement surface and which each emit, in a third direction, a second laser beam in a second peak wavelength range; a plurality of first mirror members, one or more of which are disposed on each placement surface and which each reflect the first laser beam in the first direction; a plurality of second mirror members, one or more of which are disposed on each placement surface and which each reflect the second laser beam in the first direction; and a condensing lens which combines a plurality of laser beams including the first and second laser beams that have been reflected by the first and second mirror members.

Description

Light-emitting module

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

[0002] In recent years, with the increasing power output of semiconductor laser elements, a technology is being developed in which a laser light source including a semiconductor laser element is used not as an excitation light source but as a light source of laser light for processing materials. Such a technology is called a direct diode laser (DDL) technology.

[0003] The DDL technology uses a light emitting module equipped with multiple laser light sources. The light emitting module combines multiple laser beams emitted from the multiple laser light sources to emit a high-power combined beam. Patent Document 1 discloses an example of a light emitting module used in the DDL technology.

[0004] Japanese Patent Application Laid-Open No. 2022-028425

[0005] To provide a light emitting module capable of increasing the output of a combined beam by increasing the number of mounted laser light sources, or capable of reducing the convergence angle of light when focused onto a fiber while maintaining the number of mounted laser light sources.

[0006] In one embodiment, the light-emitting module of the present disclosure includes a support base having a plurality of mounting surfaces aligned in a first direction, the heights of the plurality of mounting surfaces from a reference plane parallel to the first direction decreasing along the first direction; a plurality of first laser light sources, one or more of which are arranged on each of the plurality of mounting surfaces, each emitting a first laser beam in a first peak wavelength region in a second direction intersecting the first direction; a plurality of second laser light sources, one or more of which are arranged on each of the plurality of mounting surfaces, each emitting a second laser beam in a second peak wavelength region different from the first peak wavelength region in a third direction intersecting the first direction; and a plurality of second laser light sources, one or more of which are arranged on each of the plurality of mounting surfaces, each emitting a second laser beam in a second peak wavelength region different from the first peak wavelength region in a third direction intersecting the first direction. one or more first mirror members are arranged on each of the plurality of mounting surfaces, each of which reflects the first laser beam emitted from the corresponding first laser light source in the first direction; one or more second mirror members are arranged on each of the plurality of mounting surfaces, each of which reflects the second laser beam emitted from the corresponding second laser light source in the first direction; and a condenser lens that combines a plurality of laser beams including the first laser beam emitted from each of the plurality of first laser light sources and reflected by the corresponding first mirror member, and the second laser beam emitted from each of the plurality of second laser light sources and reflected by the corresponding second mirror member.

[0007] According to the embodiments of the present disclosure, it is possible to realize a light emitting module capable of increasing the output of a combined beam by increasing the number of mounted laser light sources, or a light emitting module capable of reducing the convergence angle of light when focused onto a fiber while maintaining the number of mounted laser light sources.

[0008] FIG. 1A is a top view schematically showing the configuration of a light emitting module according to a first exemplary embodiment of the present disclosure. FIG. 1B is a side view schematically showing the configuration of a light emitting module according to a first exemplary embodiment of the present disclosure. FIG. 2 is a top view schematically showing the configuration of a light emitting module according to a first other exemplary embodiment of the present disclosure. FIG. 3 is a top view schematically showing the configuration of a light emitting module according to a second exemplary embodiment of the present disclosure. FIG. 4 is a top view schematically showing the configuration of a light emitting module according to a second other exemplary embodiment of the present disclosure. FIG. 5A is a top view schematically showing the configuration of a modified example of the laser light source shown in FIGS. 1A and 2. FIG. 5B is a top view schematically showing the configuration of a modified example of the laser light source shown in FIG. 4. FIG. 5C is a top view schematically showing the configuration of another modified example of the laser light source shown in FIGS. 1A and 2. FIG. 5D is a top view schematically showing the configuration of yet another modified example of the laser light source shown in FIGS. 1A and 2. FIG. 6 is a diagram schematically showing the configuration of a DDL device according to an exemplary embodiment of the present disclosure. Fig. 7A is an exploded perspective view of a laser light source. Fig. 7B is a cross-sectional view parallel to the XY plane of the laser light source. Fig. 8A is a perspective view schematically showing a configuration example of a first light-emitting device. Fig. 8B is a cross-sectional view schematically showing a configuration example of the first light-emitting device. Fig. 9A is a perspective view schematically showing another configuration example of the first light-emitting device. Fig. 9B is a cross-sectional view schematically showing another configuration example of the first light-emitting device.

[0009] Hereinafter, a light emitting module according to an embodiment of the present disclosure will be described with reference to the drawings. Parts that appear in multiple drawings with the same reference numerals indicate the same or equivalent parts.

[0010] Furthermore, the embodiments described below are examples to embody the technical idea of ​​the present invention, and do not limit the present invention. Furthermore, the size, material, shape, relative arrangement, etc. of components are intended to be illustrative and not to limit the scope of the present invention. The size and positional relationship of components shown in each drawing may be exaggerated to facilitate understanding.

[0011] In this specification and claims, polygons such as triangles and quadrilaterals are referred to as polygons, including shapes in which the corners of the polygon have been rounded, chamfered, corner-cut, or rounded. Shapes in which processing has been applied not only to the corners (edges of the sides) but also to the middle of the sides are also referred to as polygons. In other words, shapes in which partial processing has been applied while retaining the polygonal base are included in the interpretation of "polygon" described in this specification and claims.

[0012] (Embodiment 1) [Configuration Example of Light-Emitting Module According to Embodiment 1] First, with reference to FIGS. 1A and 1B, a configuration example of a light-emitting module according to Embodiment 1 of the present disclosure will be described. FIGS. 1A and 1B are top and side views, respectively, that schematically illustrate the configuration of a light-emitting module according to exemplary Embodiment 1 of the present disclosure. The light-emitting module 100A1 shown in FIGS. 1A and 1B emits a combined beam formed by combining multiple first laser beams and multiple second laser beams. The peak wavelengths of the first and second laser beams, more specifically, the peak wavelength regions described below, are different from each other. The light-emitting module 100A1 can be used, for example, to process an object using the combined beam.

[0013] In the accompanying drawings, including Figures 1A and 1B, mutually orthogonal X-axis, Y-axis, and Z-axis are shown schematically for reference. The direction of the X-axis arrow 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 ease of explanation, the +Y direction is referred to as "upward" and the -Y direction is referred to as "downward." This does not limit the orientation of the light-emitting module 100A1 during use, and the orientation of the light-emitting module 100A1 is arbitrary.

[0014] 1A , the light-emitting module 100A1 includes a support base 10, a plurality of first laser light sources 20a, a plurality of second laser light sources 20b, a plurality of first slow-axis collimating lenses 30a, a plurality of second slow-axis collimating lenses 30b, a plurality of first mirror members 40a, a plurality of second mirror members 40b, and a condenser lens 50. The light-emitting module 100A1 further includes an optical fiber 60 and a support member 62 that supports the optical fiber 60.

[0015] As shown in FIG. 1B , the support base 10 is disposed on a reference plane Ref parallel to the Z direction, more specifically, parallel to the XZ plane. The reference plane Ref is a reference plane for the height of the light-emitting module 100A1. The support base 10 has a plurality of first mounting surfaces 12a and a second mounting surface 12b. The first mounting surfaces 12a are arranged in a stepped pattern in the Z direction. The height of the first mounting surfaces 12a decreases along the +Z direction as shown in FIG. 1B . As shown in FIG. 1A , the second mounting surface 12b is located in the +Z direction relative to the first mounting surfaces 12a in a top view seen from the normal direction of each first mounting surface 12a. The normal direction of each first mounting surface 12a is the +Y direction. The same applies to the normal direction of the second mounting surface 12b. In this specification, the normal direction of a surface is a direction perpendicular to the surface and away from the object having that surface.

[0016] 1B, the height of the second mounting surface 12b is smaller than the smallest height of the first mounting surfaces 12a, but this is not limiting. The height of the second mounting surface 12b may be the same as the smallest height of the first mounting surfaces 12a, or may be larger than the smallest height of the first mounting surfaces 12a.

[0017] A plurality of first laser light sources 20a, a plurality of first slow-axis collimating lenses 30a, and a plurality of first mirror members 40a are arranged on the plurality of first mounting surfaces 12a. In other words, as shown in FIG. 1A , a corresponding first laser light source 20a, a corresponding first slow-axis collimating lens 30a, and a corresponding first mirror member 40a are arranged on each first mounting surface 12a. The number of corresponding first laser light sources 20a may be two or more, rather than one. That is, the number of corresponding first laser light sources 20a is one or more. The same applies to the number of corresponding first slow-axis collimating lenses 30a and the number of corresponding first mirror members 40a.

[0018] Similarly, a plurality of second laser light sources 20b, a plurality of second slow-axis collimating lenses 30b, and a plurality of second mirror members 40b are arranged on the plurality of first mounting surfaces 12a. In other words, a corresponding second laser light source 20b, a corresponding second slow-axis collimating lens 30b, and a corresponding second mirror member 40b are arranged on each first mounting surface 12a. The number of corresponding second laser light sources 20b may be two or more, rather than one. That is, the number of corresponding second laser light sources 20b is one or more. The same applies to the number of corresponding second slow-axis collimating lenses 30b and the number of corresponding second mirror members 40b.

[0019] A condenser lens 50 is disposed on the second mounting surface 12b. An optical fiber 60 is further disposed on the second mounting surface 12b via a support member 62.

[0020] 1A and 1B, the number of first laser light sources 20a implemented is four, but is not limited to this number. The number of first laser light sources 20a implemented may be two, three, or five or more. The same applies to the number of second laser light sources 20b implemented. The number of second laser light sources 20b implemented may be the same as the number of first laser light sources 20a implemented, or may be more or less than the number of first laser light sources 20a implemented.

[0021] The number of first slow-axis collimating lenses 30a is the same as the number of first laser light sources 20a, and the number of second slow-axis collimating lenses 30b is the same as the number of second laser light sources 20b. The number of first mirror members 40a is the same as the number of first laser light sources 20a, and the number of second mirror members 40b is the same as the number of second laser light sources 20b. The number of first mounting surfaces 12a may be the same as or greater than the larger of the number of first laser light sources 20a and the number of second laser light sources 20b.

[0022] The thick solid line with arrows in Figures 1A and 1B represents the first laser beam La emitted from the first laser light source 20a. The thick dotted line with arrows in Figures 1A and 1B represents the second laser beam Lb emitted from the second laser light source 20b. The first laser beam La and the second laser beam Lb in Figure 1A are represented by thick lines with three arrows, while the first laser beam La and the second laser beam Lb in Figure 1B are represented by thick lines with one arrow. This is to emphasize that the spread of the first laser beam La and the second laser beam Lb in the XZ plane is larger than the spread of the first laser beam La and the second laser beam Lb in the YZ plane.

[0023] The first laser beams La emitted from the first laser light sources 20a may have the same peak wavelength, but do not necessarily have the same peak wavelength. Similarly, the second laser beams Lb emitted from the second laser light sources 20b may have the same peak wavelength, but do not necessarily have the same peak wavelength. In this sense, the peak wavelengths of the first laser beams La can be said to be included in a first peak wavelength region, and the peak wavelengths of the second laser beams Lb can be said to be included in a second peak wavelength region. The second peak wavelength region is different from the first peak wavelength region and does not overlap with the first peak wavelength region. The wavelength width of each peak wavelength region can be determined, for example, by the difference between the longest and shortest peak wavelengths among the peak wavelengths included in each peak wavelength region. The wavelength width of each peak wavelength region can be, for example, 10 nm or less or 5 nm or less.

[0024] As will be described in detail later, in the light-emitting module 100A1 according to the first embodiment, a first laser light source 20a and a second laser light source 20b that respectively emit a first laser beam La and a second laser beam Lb of different peak wavelength regions are arranged on each of the plurality of first mounting surfaces 12a. That is, since both the first laser light source 20a and the second laser light source 20b, rather than only one of them, are arranged on the same first mounting surface 12a, it is possible to increase the number of first laser light sources 20a and second laser light sources 20b mounted in the light-emitting module 100A1 and to increase the output of the combined beam.

[0025] The components of the light emitting module 100A1 will be described below.

[0026] 1A , the support base 10 supports a plurality of first laser light sources 20a, a plurality of second laser light sources 20b, a plurality of first slow-axis collimating lenses 30a, a plurality of second slow-axis collimating lenses 30b, a plurality of first mirror members 40a, a plurality of second mirror members 40b, and a condenser lens 50, and also supports an optical fiber 60 via a support member 62. In the support base 10, the side on which the first mounting surface 12a and the second mounting surface 12b are located is the "upper side," and the opposite side is the "lower side." The components arranged on the first mounting surface 12a and the second mounting surface 12b are as described above.

[0027] 1A, the support base 10 has a rectangular shape when viewed from above, but is not limited to this example. The support base 10 may have, for example, a circular shape or an elliptical shape when viewed from above.

[0028] The support base 10 functions as a support table on which the first laser light source 20a and the second laser light source 20b are placed. The support base 10 can also function as a heat sink that transfers heat generated from the first laser light source 20a and the second laser light source 20b to the outside to reduce excessive temperature rise in the first laser light source 20a and the second laser light source 20b. In this case, one or more flow paths for liquid cooling may be provided inside the support base 10. The liquid for liquid cooling may be, for example, water. Furthermore, a fin structure for air cooling may be provided on the surface of the support base 10. Alternatively, when the support base 10 is placed on a separately prepared heat sink, the support base 10 can also function as a heat spreader that transfers heat generated from the first laser light source 20a and the second laser light source 20b to the heat sink.

[0029] The support substrate 10 may be formed of, for example, a ceramic selected from the group consisting of AlN, SiN, SiC, and alumina. Alternatively, the support substrate 10 may be formed of, for example, at least one metal material selected from the group consisting of Cu, Al, Au, CuW, CuMo, and Ag. The support substrate 10 may be formed of, for example, a metal matrix composite material in which diamond particles are dispersed in at least one metal material selected from the group consisting of Cu, Al, and Ag. The support substrate 10 may be formed of, for example, graphite or a graphite composite material.

[0030] The support base 10 is preferably made of a metal material selected from the group consisting of Cu, Al, and Ag, and is made of a single member. Metal materials have better heat dissipation properties than ceramics, and are soft and therefore easy to process.

[0031] <First Laser Light Source 20a and Second Laser Light Source 20b> As shown in FIG. 1A , each first laser light source 20a emits a first laser beam La having a peak wavelength included in a first peak wavelength region in the −X direction. Each second laser light source 20b emits a second laser beam Lb having a peak wavelength included in a second peak wavelength region in the −X direction. In this specification, the first laser beam La having a peak wavelength included in the first peak wavelength region will also be simply referred to as the “first laser beam La in the first peak wavelength region.” Similarly, the second laser beam Lb having a peak wavelength included in the second peak wavelength region will also be simply referred to as the “second laser beam Lb in the second peak wavelength region.”

[0032] The emission directions of the first laser beam La and the second laser beam Lb are the same. Even if the optical axes of the first laser beam La and the second laser beam Lb are not strictly parallel, this is permissible as long as the absolute value of the acute angle between these optical axes is 10° or less. The first laser beam La and the second laser beam Lb are collimated in the XY plane but not in the XZ plane. The first laser light source 20a and the second laser light source 20b are disposed adjacent to each other on the same first mounting surface 12a.

[0033] The wavelength width of the intermediate wavelength region between the first peak wavelength region and the second peak wavelength region can be, for example, 5 nm or more and 100 nm or less, more preferably 5 nm or more and 50 nm or less. If the wavelength width of the intermediate wavelength region is, for example, 5 nm or more, a dichroic mirror can be used as the second mirror member 40b that transmits the first laser beam La and reflects the second laser beam Lb, as described below. If the wavelength width of the intermediate wavelength region is, for example, 100 nm or less, the first and second peak wavelengths can be contained within a wavelength range in which the optical absorption rate of the processing target is high. If the wavelength width of the intermediate wavelength region is, for example, 50 nm or less, an optical element having wavelength-dependent optical characteristics, such as the condenser lens 50, can be used in common regardless of wavelength. However, slight differences due to wavelength dependency may occur.

[0034] The first laser light source 20a and the second laser light source 20b are so-called chip-on-submount semiconductor laser light sources. The following components of the first laser light source 20a and the second laser light source 20b may be treated as components of the light emitting module 100A1.

[0035] As shown in the enlarged view of FIG. 1A , the first laser light source 20a includes a first submount 21a, an edge-emitting first semiconductor laser element 22a, a first lens support member 23a, and a first fast-axis collimating lens 24a. The first semiconductor laser element 22a is disposed on the first mounting surface 12a of the support base 10 via the first submount 21a. The first lens support member 23a has a shape that straddles the first semiconductor laser element 22a. The first lens support member 23a supports the first fast-axis collimating lens 24a by its end face. The focal point of the first fast-axis collimating lens 24a is located on the emission surface of the first semiconductor laser element 22a.

[0036] Similarly, the second laser light source 20b includes a second submount 21b, an edge-emitting second semiconductor laser element 22b, a second lens support member 23b, and a second fast axis collimating lens 24b. The second semiconductor laser element 22b is disposed on the first mounting surface 12a of the support base 10 via the second submount 21b. The second lens support member 23b has a shape that straddles the second semiconductor laser element 22b. The second lens support member 23b supports the second fast axis collimating lens 24b by its end face. The focal point of the second fast axis collimating lens 24b is located on the emission surface of the second semiconductor laser element 22b.

[0037] The first laser light source 20a emits the first laser beam La as follows: In this description, the components of the first laser light source 20a may be replaced with the components of the second laser light source 20b, and the first laser beam La may be replaced with the second laser beam Lb.

[0038] The first semiconductor laser element 22a emits laser light from a rectangular end face. When the end face extends in the Z direction and is a plane parallel to the YZ plane, the laser light emitted from the first semiconductor laser element 22a in the −X direction spreads relatively quickly in the XY plane and spreads relatively slowly in the XZ plane. The fast axis direction of the laser light is parallel to the Y direction, and the slow axis direction is parallel to the Z direction.

[0039] The first laser light source 20a emits laser light emitted from the first semiconductor laser element 22a and transmitted through the first fast axis collimating lens 24a as a first laser beam La. The first laser beam La is collimated in the XY plane but not in the XZ plane. In this specification, "collimating" means not only making the laser light parallel, but also reducing the spread of the laser light.

[0040] Instead of the edge-emitting first semiconductor laser element 22a, a surface-emitting semiconductor laser element such as a vertical-cavity surface-emitting laser (VCSEL) element may be used. The surface-emitting semiconductor laser element is arranged so that the laser light emitted from the semiconductor laser element travels in the −X direction.

[0041] In the first laser light source 20a, the first submount 21a, the first lens support member 23a, and the first fast axis collimating lens 24a other than the first semiconductor laser element 22a may be omitted in some cases. If it is not necessary to raise the bottom of the first semiconductor laser element 22a, the first submount 21a is not necessarily required. If the laser light emitted from the first semiconductor laser element 22a is already collimated, the first lens support member 23a and the first fast axis collimating lens 24a are not necessarily required.

[0042] The first laser beam La and the second laser beam Lb are actually light beams having an intensity distribution in a plane perpendicular to the direction of travel. This intensity distribution can be approximated by a distribution function such as a Gaussian distribution in the plane perpendicular to the direction of travel of the light beam. The diameter of the light beam, i.e., the beam diameter, is, for example, 1 / e with respect to the intensity at the beam center. ２ The beam diameter in the Y direction of the first laser beam La and the second laser beam Lb may be, for example, 0.1 mm or more and 0.5 mm or less.

[0043] 1A , a first laser light source 20a and a second laser light source 20b that respectively emit a first laser beam La and a second laser beam Lb having different peak wavelength regions are disposed on each first mounting surface 12a. Since the first laser light source 20a and the second laser light source 20b are disposed on the same first mounting surface 12a, the number of first laser light sources 20a and second laser light sources 20b mounted in the light-emitting module 100A1 can be increased. Compared to a configuration in which only one of the first laser light source 20a and the second laser light source 20b is disposed on each first mounting surface 12a, the number of first laser light sources 20a and second laser light sources 20b mounted in the light-emitting module 100A1 is doubled.

[0044] In this specification, the phrase "the first laser light source 20a and the second laser light source 20b are arranged on each first mounting surface 12a" means that the beam diameters of the first laser beam La and the second laser beam Lb emitted from the first laser light source 20a and the second laser light source 20b, respectively, on each first mounting surface 12a at least partially overlap in the Y direction when viewed from a direction parallel to the XZ plane. In this case, the first mounting surface 12a may be flat or may have steps and / or irregularities.

[0045] As described above, on each first mounting surface 12 a, the number of first laser light sources 20 a may be 1 or more, and the number of second laser light sources 20 b may be 1 or more. In this case, among all the first laser beams La and all the second laser beams Lb emitted from all the first laser light sources 20 a and all the second laser light sources 20 b arranged on each first mounting surface 12 a, the beam diameter of any one laser beam and the beam diameters of the remaining laser beams at least partially overlap in the Y direction when viewed from a direction parallel to the XZ plane.

[0046] In the light-emitting module 100A1, the first laser light source 20a and the second laser light source 20b are arranged on the same first mounting surface 12a, so the number of first mounting surfaces 12a can be reduced compared to a configuration in which the same number of mounted laser light sources are arranged one on each mounting surface. Therefore, the number of steps can also be reduced, so the dimension of the support base 10 in the Y direction does not become excessively large compared to this configuration, preventing the light-emitting module 100A1 from becoming large in the Y direction. Furthermore, because the dimension of the support base 10 in the Y direction does not become excessively large, heat emitted from the first laser light source 20a and the second laser light source 20b arranged on each first mounting surface 12a, including the highest first mounting surface 12a, can be effectively conducted downward via the support base 10 or to the aforementioned flow path provided in the support base 10.

[0047] Of the multiple first mounting surfaces 12a arranged in a stepped pattern in the +Z direction, the step between two adjacent first mounting surfaces 12a can be, for example, greater than 80% of the beam diameter of each of the first laser beam La and the second laser beam Lb, but not greater than four times this beam diameter. If the step between two adjacent first mounting surfaces 12a is greater than 80% of the beam diameter of each of the first laser beam La and the second laser beam Lb, most of the first laser beam La and the second laser beam Lb reflected by the first mirror member 40a and the second mirror member 40b, respectively, can travel in the +Z direction without hitting the first mounting surface 12a or the other first mirror members 40a and second mirror members 40b. As long as the step between two adjacent first mounting surfaces 12a is four times or less the beam diameter of each of the first laser beam La and the second laser beam Lb, a large number of first mounting surfaces 12a on which the first laser light source 20a and the second laser light source 20b are disposed can be provided in the Y direction. This allows the number of first laser light sources 20a and second laser light sources 20b to be increased in the light-emitting module 100A1. Furthermore, if the step between two adjacent first mounting surfaces 12a among the multiple first mounting surfaces 12a arranged in a stepped pattern in the +Z direction is larger than the beam diameter of each of the first laser beam La and the second laser beam Lb, the first laser beam La and the second laser beam Lb after the reflection can travel in the +Z direction without hitting the first mirror member 40a and the second mirror member 40b.

[0048] The plurality of first laser light sources 20 a may have the same structure, including, for example, shape, material, and dimensions. Such a plurality of first laser light sources 20 a is advantageous in that it is easy to prepare. The same applies to the plurality of second laser light sources 20 b.

[0049] The polarization directions of the multiple first laser beams La emitted from the multiple first laser light sources 20a may all be, for example, the same direction. Alternatively, some of the polarization directions of the multiple first laser beams La may be different from the polarization directions of the remaining first laser beams La. The polarization direction of the first laser beam La traveling in the -X direction may be parallel to the Y direction or the Z direction, for example. The same applies to the polarization directions of the multiple second laser beams Lb emitted from the multiple second laser light sources 20b.

[0050] 1A, each first slow-axis collimating lens 30a collimates the first laser beam La emitted from the corresponding first laser light source 20a in the XZ plane. Each second slow-axis collimating lens 30b collimates the second laser beam Lb emitted from the corresponding second laser light source 20b in the XZ plane. The first slow-axis collimating lens 30a and the second slow-axis collimating lens 30b are arranged adjacent to each other on the same first mounting surface 12a.

[0051] The focal point of each first slow-axis collimating lens 30a is located on the emission surface of the first semiconductor laser element 22a included in the corresponding first laser light source 20a. The focal point of each second slow-axis collimating lens 30b is located on the emission surface of the second semiconductor laser element 22b included in the corresponding second laser light source 20b. The optical axes of the first slow-axis collimating lens 30a and the second slow-axis collimating lens 30b are parallel to the X direction.

[0052] The first slow axis collimating lens 30a and the second slow axis collimating lens 30b can be appropriately designed according to the peak wavelength regions of the first laser beam La and the second laser beam Lb, for example, as follows: The first slow axis collimating lens 30a is designed to accurately collimate the first laser beam La in the first peak wavelength region. The second slow axis collimating lens 30b is designed to accurately collimate the second laser beam Lb in the second peak wavelength region.

[0053] The plurality of first slow-axis collimating lenses 30 a may have the same structure, including, for example, shape, material, and dimensions. Such a plurality of first slow-axis collimating lenses 30 a is advantageous in that they are easy to prepare. The same is true for the plurality of second slow-axis collimating lenses 30 b.

[0054] The first slow axis collimating lens 30a and the second slow axis collimating lens 30b may be formed from at least one light-transmitting material selected from the group consisting of, for example, glass, silicon, quartz, synthetic quartz, sapphire, transparent ceramics, silicone resin, and plastic.

[0055] In addition, if the first laser beam La and the second laser beam Lb emitted from the first laser light source 20a and the second laser light source 20b, respectively, are collimated not only in the XY plane but also in the XZ plane, there is no need to arrange the first slow axis collimating lens 30a and the second slow axis collimating lens 30b.

[0056] <First Mirror Member 40a and Second Mirror Member 40b> As shown in FIG. 1A, each first mirror member 40a reflects the first laser beam La emitted from the corresponding first laser light source 20a in the +Z direction. Each second mirror member 40b reflects the second laser beam Lb emitted from the corresponding second laser light source 20b in the +Z direction. Each second mirror member 40b also transmits the first laser beam La reflected in the +Z direction by the first mirror member 40a disposed on the corresponding first mounting surface 12a. In this manner, the second mirror member 40b wavelength-combines the first laser beam La and the second laser beam Lb. As shown in FIG. 1B, the wavelength-combined first laser beam La and the second laser beam Lb at least partially overlap when viewed from the X direction. Therefore, the optical axes of the first laser beam La and the second laser beam Lb are approximately the same height. The second mirror member 40b may be, for example, a dichroic mirror. The first mirror member 40a and the second mirror member 40b are disposed adjacent to each other on the same first mounting surface 12a.

[0057] 1A, since the second mirror member 40b transmits the first laser beam La, the corresponding first mirror member 40a and second mirror member 40b arranged on each first mounting surface 12a may be at the same position in the X direction. In other words, it is not necessary to arrange the first mirror member 40a and the second mirror member 40b with a shift in the X direction. Therefore, the dimension of the support base 10 in the X direction does not become excessively large, and the light-emitting module 100A1 can be prevented from becoming large in size in the X direction.

[0058] The advantages of wavelength-combining the first laser beam La and the second laser beam Lb within the light-emitting module 100A1 are as follows. Unlike the light-emitting module 100A1, a configuration including a light-emitting module that emits a combined beam formed by combining multiple first laser beams La and another light-emitting module that emits a combined beam formed by combining multiple second laser beams Lb requires additional optical components for wavelength-combining these combined beams outside the two light-emitting modules. Therefore, this configuration is large and requires a large number of components. In contrast, the light-emitting module 100A1 is not large and requires fewer components, even if the output of the combined beam formed by combining multiple first laser beams La and multiple second laser beams Lb is the same. This also leads to reduced manufacturing costs.

[0059] The first mirror member 40a and the second mirror member 40b can be appropriately designed according to the peak wavelength regions of the first laser beam La and the second laser beam Lb, for example, as follows: The first mirror member 40a is designed to highly efficiently reflect the first laser beam La in the first peak wavelength region. The second mirror member 40b is designed to highly efficiently reflect the second laser beam Lb in the second peak wavelength region and to highly efficiently transmit the first laser beam La in the first peak wavelength region.

[0060] The first mirror members 40a may have the same structure, including the same shape, material, and dimensions. Such a plurality of first mirror members 40a is advantageous in that they are easy to prepare. The same is true for the second mirror members 40b.

[0061] The first mirror member 40a and the second mirror member 40b may be formed, for example, from a dielectric multilayer film with low optical loss. If optical loss is not a consideration, the first mirror member 40a, which does not need to transmit the second laser beam Lb, may be formed, for example, from a metal material. If it is not necessary to transmit the first laser beam La, as will be described later, the second mirror member 40b may also be formed, for example, from a metal material.

[0062] 1A and 1B, the condenser lens 50 combines the following multiple laser beams: The multiple laser beams include a first laser beam La emitted from each first laser light source 20a and reflected in the +Z direction by the corresponding first mirror member 40a, and a second laser beam Lb emitted from each second laser light source 20b and reflected in the +Z direction by the corresponding second mirror member 40b.

[0063] The condenser lens 50 has a fast axis condenser lens 50a and a slow axis condenser lens 50b. The fast axis condenser lens 50a is disposed so that its focal point substantially coincides with the incident end face of the optical fiber 60. Similarly, the slow axis condenser lens 50b is disposed so that its focal point substantially coincides with the incident end face of the optical fiber 60. The focal length of the fast axis condenser lens 50a is longer than the focal length of the slow axis condenser lens 50b.

[0064] As shown in FIG. 1B , the fast axis focusing lens 50a focuses the multiple laser beams onto the incident end face of the optical fiber 60 in the YZ plane. As shown in FIG. 1A , the slow axis focusing lens 50b focuses the multiple laser beams, each of which has a divergence, onto the incident end face in the XZ plane. In this manner, the focusing lens 50 combines the multiple laser beams to form a combined beam. As a result, the light-emitting module 100A1 emits the combined beam from the output end face of the optical fiber 60. The output power of the combined beam is roughly equal to the sum of the output power of the first laser beam La multiplied by the number of first laser light sources 20a and the output power of the second laser beam Lb multiplied by the number of second laser light sources 20b.

[0065] The fast axis focusing lens 50a may be, for example, a cylindrical lens having a uniform cross-sectional shape in the X direction, and the slow axis focusing lens 50b 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 50a and the slow axis focusing lens 50b are parallel to the Z direction. The focusing lens 50 may be formed from at least one light-transmitting material selected from the group consisting of, for example, glass, silicon, quartz, synthetic quartz, sapphire, transparent ceramics, silicone resin, and plastic.

[0066] <Optical fiber 60> The optical fiber 60 emits the combined beam incident on its input end face from its output end face. The polarization state of the combined beam can change as it passes through the optical fiber 60. Therefore, even if the combined beam is polarized in a specific direction at the input end face, it may be unpolarized, for example, at the output end face. Because the optical fiber 60 can be of any length and bendable, the combined beam can be emitted in any direction from the output end face of the optical fiber 60, making it possible to extract the combined beam outside the light-emitting module 100A1.

[0067] 1B , the distance in the Y direction between the optical axis of the top laser beam and the optical axis of the bottom laser beam is defined as the width of the laser beams. If the width of the laser beams is excessively wide, the following problem may occur: If the width of the laser beams is excessively wide, the outer portion of the combined beam, which is far from the center, that is combined by the focusing lens 50 will have an excessively large angle of incidence when it enters the incident end face of the optical fiber 60. Due to the limitation imposed by the numerical aperture of the optical fiber 60, the outer portion of the combined beam cannot propagate through the optical fiber 60.

[0068] The width of the multiple laser beams depends on the step between two adjacent first mounting surfaces 12a and the number of first mounting surfaces 12a. Unlike the light-emitting module 100A1, in a configuration in which the same number of laser light sources are mounted, one on each mounting surface, the number of mounted laser light sources can be increased by increasing the number of mounting surfaces. However, if the width of the multiple laser beams is excessively wide, the outer portion of the combined beam cannot propagate through the optical fiber, and the output of the combined beam extracted through the optical fiber decreases.

[0069] In contrast, in the light-emitting module 100A1, the first laser light source 20a and the second laser light source 20b can be arranged on the same first mounting surface 12a, allowing for an increased number of first laser light sources 20a and second laser light sources 20b to be mounted. This prevents the width of the multiple laser beams from becoming excessively wide, allowing the outer portions of the combined beam to propagate through the optical fiber 60, and maintaining a high output value for the combined beam extracted via the optical fiber 60. Alternatively, the light-emitting module 100A1 can reduce the angle of light convergence on the fiber while maintaining the same number of mounted laser light sources. This is because the same number of laser light sources can be mounted even with a reduced number of mounting surfaces.

[0070] As described above, in the light-emitting module 100A1 according to the first embodiment, a first laser light source 20a and a second laser light source 20b that respectively emit a first laser beam La and a second laser beam Lb having different peak wavelength regions are disposed on each of the plurality of first mounting surfaces 12a. That is, since both the first laser light source 20a and the second laser light source 20b are disposed on the same first mounting surface 12a, rather than only one of them, the number of first laser light sources 20a and second laser light sources 20b mounted in the light-emitting module 100A1 can be increased to increase the output of the combined beam. Alternatively, the angle of light focused on the fiber can be reduced while maintaining the number of mounted laser light sources.

[0071] Furthermore, in the light-emitting module 100A1 according to the first embodiment, the number of steps can be reduced, so that the dimension of the support base 10 in the Y direction does not become excessively large. Therefore, heat emitted from the first laser light sources 20a and the second laser light sources 20b arranged on each first mounting surface 12a, including the highest first mounting surface 12a, can be effectively conducted downward via the support base 10 or to the above-mentioned flow path provided in the support base 10.

[0072] Furthermore, in the light emitting module 100A1 according to the first embodiment, the first laser beam La and the second laser beam Lb are wavelength-combined within the light emitting module 100A1. This prevents the light emitting module 100A1 from becoming large and requires fewer components, which also leads to reduced manufacturing costs.

[0073] 1A and 1B, three or more laser light sources emitting laser beams in different, non-overlapping peak wavelength ranges may be arranged on the same first mounting surface 12a. In this case, the number of mounted laser light sources can be further increased. The same applies to the embodiments described below.

[0074] Another exemplary configuration of the light-emitting module according to the first embodiment of the present disclosure will now be described with reference to FIG. 2 . FIG. 2 is a top view schematically illustrating the configuration of a light-emitting module according to the first embodiment of the present disclosure. For simplicity, the first laser beam La and the second laser beam Lb, as well as the third laser beam Lc and the fourth laser beam Ld described below, are represented by a thick line with a single arrowhead. The light-emitting module 100A2 shown in FIG. 2 differs from the light-emitting module 100A1 shown in FIGS. 1A and 1B in the following three respects.

[0075] The first feature is that the light-emitting module 100A2 further includes, on the first mounting surfaces 12a, a plurality of third laser light sources 20c, a plurality of fourth laser light sources 20d, a plurality of third slow-axis collimating lenses 30c, a plurality of fourth slow-axis collimating lenses 30d, a plurality of third mirror members 40c, and a plurality of fourth mirror members 40d. The second feature is that the light-emitting module 100A2 further includes, on the second mounting surface 12b, an auxiliary mirror member 72, a wave plate 74, and a polarizing beam splitter 76. The third feature is that the light-emitting module 100A2 includes a support base 10 having different dimensions of the first mounting surface 12a and the second mounting surface 12b compared to the light-emitting module 100A1. Due to the first feature, the dimension of the first mounting surface 12a in the X direction is larger. Due to the second feature, the dimension of the second mounting surface 12b in the Z direction is larger.

[0076] A plurality of third laser light sources 20c, a plurality of third slow-axis collimating lenses 30c, and a plurality of third mirror members 40c are arranged on the plurality of first mounting surfaces 12a. In other words, a corresponding third laser light source 20c, a corresponding third slow-axis collimating lens 30c, and a corresponding third mirror member 40c are arranged on each first mounting surface 12a. The number of corresponding third laser light sources 20c may be two or more, rather than one. That is, the number of corresponding third laser light sources 20c is one or more. The same applies to the number of corresponding third slow-axis collimating lenses 30c and the number of corresponding third mirror members 40c.

[0077] Similarly, a plurality of fourth laser light sources 20d, a plurality of fourth slow-axis collimating lenses 30d, and a plurality of fourth mirror members 40d are arranged on the plurality of first mounting surfaces 12a. In other words, a corresponding fourth laser light source 20d, a corresponding fourth slow-axis collimating lens 30d, and a corresponding fourth mirror member 40d are arranged on each first mounting surface 12a. The number of corresponding fourth laser light sources 20d may be two or more instead of one. In other words, the number of corresponding fourth laser light sources 20d is one or more. The same applies to the number of corresponding fourth slow-axis collimating lenses 30d and the number of corresponding fourth mirror members 40d.

[0078] The third laser light source 20c, the third slow-axis collimating lens 30c, and the third mirror member 40c have the same structures as the first laser light source 20a, the first slow-axis collimating lens 30a, and the first mirror member 40a, respectively. The fourth laser light source 20d, the fourth slow-axis collimating lens 30d, and the fourth mirror member 40d have the same structures as the second laser light source 20b, the second slow-axis collimating lens 30b, and the second mirror member 40b, respectively.

[0079] 2, the third laser light source 20c includes a third submount 21c, an edge-emitting third semiconductor laser element 22c, a third lens support member 23c, and a third fast-axis collimating lens 24c. The third submount 21c, the third semiconductor laser element 22c, and the third fast-axis collimating lens 24c have the same structures as the first submount 21a, the first semiconductor laser element 22a, and the first fast-axis collimating lens 24a, respectively.

[0080] 2, the fourth laser light source 20d includes a fourth submount 21d, an edge-emitting fourth semiconductor laser element 22d, a fourth lens support member 23d, and a fourth fast-axis collimating lens 24d. The fourth submount 21d, the fourth semiconductor laser element 22d, and the fourth fast-axis collimating lens 24d have the same structures as the second submount 21b, the second semiconductor laser element 22b, and the second fast-axis collimating lens 24b, respectively.

[0081] On the same first mounting surface 12a, the arrangements of the first laser light source 20a and the third laser light source 20c are in a mutually inverted relationship in the X direction. The same is true for the arrangements of the first slow axis collimating lens 30a and the third slow axis collimating lens 30c, and the arrangements of the first mirror member 40a and the third mirror member 40c.

[0082] Similarly, on the same first mounting surface 12a, the arrangements of the second laser light source 20b and the fourth laser light source 20d are in a mutually inverted relationship in the X direction, as are the arrangements of the second slow-axis collimating lens 30b and the fourth slow-axis collimating lens 30d, and the arrangements of the second mirror member 40b and the fourth mirror member 40d.

[0083] As shown in FIG. 2 , each third laser light source 20c emits a third laser beam Lc having a peak wavelength included in the first peak wavelength region in the +X direction. Each fourth laser light source 20d emits a fourth laser beam Ld having a peak wavelength included in the second peak wavelength region in the +X direction. In this specification, the third laser beam Lc having a peak wavelength included in the first peak wavelength region will also be simply referred to as the "third laser beam Lc in the first peak wavelength region." Similarly, the fourth laser beam Ld having a peak wavelength included in the second peak wavelength region will also be simply referred to as the "fourth laser beam Ld in the second peak wavelength region."

[0084] The third laser beam Lc and the fourth laser beam Ld are emitted in the same direction. Even if the optical axes of the third laser beam Lc and the fourth laser beam Ld are not strictly parallel, this is permissible as long as the absolute value of the acute angle between these optical axes is 10° or less. The third laser beam Lc and the fourth laser beam Ld are collimated in the XY plane but not in the XZ plane. The third laser light source 20c and the fourth laser light source 20d are disposed adjacent to each other on the same first mounting surface 12a.

[0085] The emission directions of the third laser beam Lc and the fourth laser beam Ld are opposite to the emission directions of the first laser beam La and the second laser beam Lb. It is permissible that the optical axes of the first to fourth laser beams La to Ld are not all strictly parallel, as long as the absolute value of the acute angle formed by any two optical axes is 10° or less. Here, it is assumed that the polarization directions of the first to fourth laser beams La to Ld emitted from the first to fourth laser light sources 20a to 20d, respectively, are all parallel to the Z direction.

[0086] 2, in addition to the first laser light source 20a and the second laser light source 20b that respectively emit a first laser beam La and a second laser beam Lb in different peak wavelength regions, a third laser light source 20c and a fourth laser light source 20d that respectively emit a third laser beam Lc and a fourth laser beam Ld in different peak wavelength regions are arranged on each first mounting surface 12a. Since the first to fourth laser light sources 20a to 20d are arranged on the same first mounting surface 12a, the number of first to fourth laser light sources 20a to 20d mounted in the light-emitting module 100A2 can be further increased.

[0087] In this specification, the phrase "the third laser light source 20c and the fourth laser light source 20d are arranged on each first mounting surface 12a" means that the beam diameters of the third laser beam Lc and the fourth laser beam Ld emitted from the third laser light source 20c and the fourth laser light source 20d, respectively, on each first mounting surface 12a at least partially overlap in the Y direction when viewed from a direction parallel to the XZ plane. In this case, the first mounting surface 12a may be flat or may have steps and / or irregularities.

[0088] As described above, on each first mounting surface 12 a, the number of third laser light sources 20 c may be 1 or more, and the number of fourth laser light sources 20 d may be 1 or more. In this case, among all the third laser beams Lc and all the fourth laser beams Ld emitted from all the third laser light sources 20 c and all the fourth laser light sources 20 d arranged on each first mounting surface 12 a, the beam diameter of any one laser beam and the beam diameters of the remaining laser beams at least partially overlap in the Y direction when viewed from a direction parallel to the XZ plane.

[0089] Each third slow-axis collimating lens 30c collimates in the XZ plane the third laser beam Lc emitted from the corresponding third laser light source 20c. Each fourth slow-axis collimating lens 30d collimates in the XZ plane the fourth laser beam Ld emitted from the corresponding fourth laser light source 20d. The third slow-axis collimating lens 30c and the fourth slow-axis collimating lens 30d are disposed adjacent to each other on the same first mounting surface 12a.

[0090] Each third mirror member 40c reflects the third laser beam Lc emitted from the corresponding third laser light source 20c in the +Z direction. Each fourth mirror member 40d reflects the fourth laser beam Ld emitted from the corresponding fourth laser light source 20d in the +Z direction. Each fourth mirror member 40d also transmits the third laser beam Lc reflected in the +Z direction by the corresponding third mirror member 40c disposed on the first mounting surface 12a. In this manner, the fourth mirror member 40d wavelength-combines the third laser beam Lc and the fourth laser beam Ld. The wavelength-combined third laser beam Lc and the fourth laser beam Ld at least partially overlap when viewed from the X direction. Therefore, the optical axes of the third laser beam Lc and the fourth laser beam Ld are approximately the same height. The fourth mirror member 40d may be, for example, a dichroic mirror. The third mirror member 40c and the fourth mirror member 40d are disposed adjacent to each other on the same first mounting surface 12a.

[0091] Because the fourth mirror member 40d transmits the third laser beam Lc, the corresponding third mirror member 40c and fourth mirror member 40d arranged on each first mounting surface 12a may be at the same position in the X direction. That is, it is not necessary to arrange the corresponding third mirror member 40c and fourth mirror member 40d on each first mounting surface 12a with a shift in the X direction. Similarly, as described above, it is not necessary to arrange the corresponding first mirror member 40a and second mirror member 40b on each first mounting surface 12a with a shift in the X direction. Therefore, the dimension of the support base 10 in the X direction does not become excessively large, and the light-emitting module 100A2 can be prevented from becoming large in size in the X direction.

[0092] The auxiliary mirror member 72 reflects the third laser beam Lc and the fourth laser beam Ld traveling in the +Z direction, thereby changing the traveling direction of the third laser beam Lc and the fourth laser beam Ld to the +X direction. The wave plate 74 is a half wave plate, and changes the polarization direction of the third laser beam Lc and the fourth laser beam Ld traveling in the +X direction from the Z direction to the Y direction.

[0093] 2, the wave plate 74 is positioned to receive the third laser beam Lc and the fourth laser beam Ld after they have been reflected by the auxiliary mirror member 72, but this is not limiting. The wave plate 74 may also be positioned to receive the third laser beam Lc and the fourth laser beam Ld before they have been reflected by the auxiliary mirror member 72. Alternatively, if the polarization directions of the first to fourth laser beams La to Ld emitted from the first to fourth laser light sources 20a to 20d are parallel to the Y direction, the wave plate 74 may be positioned to receive the first laser beam La and the second laser beam Lb. In this case, the wave plate 74 changes the polarization direction of the first laser beam La and the second laser beam Lb traveling in the +Z direction from the Y direction to the X direction.

[0094] From the above, the following can be said about the first to fourth laser beams La to Ld and the wave plate 74. The first laser beam La and the second laser beam Lb or the third laser beam Lc and the fourth laser beam Ld pass through the wave plate 74, and after passing through, the polarization direction of the first laser beam La and the second laser beam Lb is perpendicular to the polarization direction of the third laser beam Lc and the fourth laser beam Ld.

[0095] The polarizing beam splitter 76 transmits so-called P-polarized light and reflects so-called S-polarized light. Therefore, the polarizing beam splitter 76 transmits the first laser beam La and the second laser beam Lb traveling in the +Z direction and whose polarization direction is parallel to the X direction, and reflects the third laser beam Lc and the fourth laser beam Ld traveling in the +X direction and whose polarization direction is parallel to the Y direction. In this way, the polarizing beam splitter 76, together with the auxiliary mirror member 72 and the wave plate 74, polarization-combines the wavelength-combined first laser beam La and the second laser beam Lb and the wavelength-combined third laser beam Lc and the fourth laser beam Ld. The polarization-combined first to fourth laser beams La to Ld are in an unpolarized state.

[0096] 2, a common auxiliary mirror member 72 and a common wave plate 74 are used for the third laser beam Lc and the fourth laser beam Ld having different peak wavelength regions. Similarly, a common polarizing beam splitter 76 is used for the first laser beam La and the second laser beam Lb having different peak wavelength regions and the third laser beam Lc and the fourth laser beam Ld having different peak wavelength regions. This allows the number of parts to be reduced. However, slight differences due to wavelength dependency may occur.

[0097] The condenser lens 50 combines the following multiple laser beams that have been wavelength-combined and polarization-combined before entering the condenser lens 50 to form a combined beam. The multiple laser beams include a first laser beam La emitted from each first laser light source 20a and reflected by the corresponding first mirror member 40a, and a second laser beam Lb emitted from each second laser light source 20b and reflected by the corresponding second mirror member 40b. The multiple laser beams further include a third laser beam Lc emitted from each third laser light source 20c and reflected by the corresponding third mirror member 40c, and a fourth laser beam Ld emitted from each fourth laser light source 20d and reflected by the corresponding fourth mirror member 40d. The optical fiber 60 emits the combined beam to the outside of the light-emitting module 100A2.

[0098] As described above, in the light-emitting module 100A2 according to the first embodiment, in addition to the first laser light source 20a and the second laser light source 20b that respectively emit the first laser beam La and the second laser beam Lb in different peak wavelength regions, the third laser light source 20c and the fourth laser light source 20d that respectively emit the third laser beam Lc and the fourth laser beam Ld in different peak wavelength regions are arranged on each of the plurality of first mounting surfaces 12a. Since the first to fourth laser light sources 20a to 20d are arranged on the same first mounting surface 12a, the number of first to fourth laser light sources 20a to 20d mounted in the light-emitting module 100A2 can be further increased, and the output of the combined beam can be further increased.

[0099] In this specification, the direction in which the multiple first mounting surfaces 12 a are arranged is also referred to as the “first direction,” the direction in which the first laser light source 20 a emits the first laser beam La is also referred to as the “second direction,” the direction in which the second laser light source 20 b emits the second laser beam Lb is also referred to as the “third direction,” the direction in which the third laser light source 20 c emits the third laser beam Lc is also referred to as the “fourth direction,” and the direction in which the fourth laser light source 20 d emits the fourth laser beam Ld is also referred to as the “fifth direction.” Furthermore, in this specification, the polarization direction of the first laser beam La and the second laser beam Lb in embodiment 1 is also referred to as the “first polarization direction,” and the polarization direction of the third laser beam Lc and the fourth laser beam Ld in embodiment 1 is also referred to as the “second polarization direction.”

[0100] The second direction may or may not be perpendicular to the first direction as long as it intersects with the first direction. The same applies to the relationship between the third direction and the first direction, the relationship between the fourth direction and the first direction, and the relationship between the fifth direction and the first direction.

[0101] 1A , in the light-emitting module 100A1 according to the first embodiment, the first laser light source 20a and the second laser light source 20b are arranged adjacent to each other on the same first mounting surface 12a. However, the first laser light source 20a and the second laser light source 20b do not necessarily have to be arranged adjacent to each other.

[0102] An exemplary configuration of a light-emitting module according to a second embodiment of the present disclosure will be described below with reference to Fig. 3 . Fig. 3 is a top view schematically illustrating the configuration of a light-emitting module according to the second exemplary embodiment of the present disclosure. For simplicity, the first laser beam La and the second laser beam Lb shown in Fig. 3 are represented by a thick line with a single arrow. The light-emitting module 100B1 shown in Fig. 3 differs from the light-emitting module 100A1 shown in Figs. 1A and 1B in the following three points.

[0103] The first difference is that on each first mounting surface 12a, the corresponding first laser light source 20a and the corresponding second laser light source 20b are arranged opposite each other, rather than adjacent to each other. The same applies to the arrangement of the corresponding first slow-axis collimating lens 30a and the corresponding second slow-axis collimating lens 30b, and the arrangement of the corresponding first mirror member 40a and the corresponding second mirror member 40b. The second difference is that the light-emitting module 100B1 further includes a first auxiliary mirror member 72a and a second auxiliary mirror member 72b on the second mounting surface 12b. The third difference is that the light-emitting module 100B1 includes a support base 10 having different dimensions for the first mounting surface 12a and the second mounting surface 12b compared to the light-emitting module 100A1. Due to the first difference, the dimension of the first mounting surface 12a in the X direction is larger and the dimension in the Z direction is smaller. Due to the second difference, the dimension of the second mounting surface 12b in the Z direction is larger.

[0104] The first laser light source 20 a and the second laser light source 20 b are arranged in a mutually inverted relationship in the X direction, as are the first slow axis collimating lens 30 a and the second slow axis collimating lens 30 b, and the first mirror member 40 a and the second mirror member 40 b.

[0105] As shown in FIG. 3, each first laser light source 20a emits a first laser beam La in the −X direction. Each second laser light source 20b emits a second laser beam Lb in the +X direction. The emission directions of the first laser beam La and the second laser beam Lb are opposite to each other. Even if the optical axes of the first laser beam La and the second laser beam Lb are not strictly parallel, this is permissible as long as the absolute value of the acute angle formed by these optical axes is 10° or less. The first laser beam La and the second laser beam Lb are collimated in the XY plane but not in the XZ plane.

[0106] 3, each first slow-axis collimating lens 30a collimates the first laser beam La emitted from the corresponding first laser light source 20a in the XZ plane. Each second slow-axis collimating lens 30b collimates the second laser beam Lb emitted from the corresponding second laser light source 20b in the XZ plane.

[0107] 3, each first mirror member 40a reflects the first laser beam La emitted from the corresponding first laser light source 20a in the +Z direction. Each second mirror member 40b reflects the second laser beam Lb emitted from the corresponding second laser light source 20b in the +Z direction. Unlike the example shown in FIG. 1A, each second mirror member 40b does not need to transmit the first laser beam La.

[0108] The first auxiliary mirror member 72a changes the direction of travel of the second laser beam Lb traveling in the +Z direction to the +X direction. The second auxiliary mirror member 72b reflects the second laser beam Lb traveling in the +X direction and transmits the first laser beam La traveling in the +Z direction. In this way, the second auxiliary mirror member 72b wavelength-combines the first laser beam La and the second laser beam Lb. The second auxiliary mirror member 72b may be, for example, a dichroic mirror.

[0109] The condenser lens 50 combines the wavelength-combined laser beams described below before entering the condenser lens 50 to form a combined beam. The multiple laser beams include first laser beams La emitted from each first laser light source 20a and reflected by the corresponding first mirror member 40a, and second laser beams Lb emitted from each second laser light source 20b and reflected by the corresponding second mirror member 40b. The optical fiber 60 emits the combined beam to the outside of the light-emitting module 100B1.

[0110] As described above, in the light-emitting module 100B1 according to the second embodiment, similarly to the light-emitting module 100A1 according to the first embodiment, the first laser light source 20a and the second laser light source 20b that respectively emit the first laser beam La and the second laser beam Lb in different peak wavelength regions are arranged on each of the plurality of first mounting surfaces 12a. Because the first laser light source 20a and the second laser light source 20b are arranged on the same first mounting surface 12a, the number of first laser light sources 20a and second laser light sources 20b mounted can be increased, thereby increasing the output of the combined beam.

[0111] Furthermore, in the light-emitting module 100B1 according to the second embodiment, the first laser light source 20a and the second laser light source 20b are arranged facing each other, not adjacent to each other, on the same first mounting surface 12a. Since the first laser light source 20a and the second laser light source 20b can be arranged facing each other on the same first mounting surface 12a, the degree of freedom in arranging the first laser light source 20a and the second laser light source 20b is increased. Furthermore, the dimension of the support base 10 in the Z direction does not become excessively large, preventing the light-emitting module 100B1 from becoming excessively large in the Z direction.

[0112] Furthermore, in the light-emitting module 100B1 according to the second embodiment, the first laser beam La and the second laser beam Lb are wavelength-combined by the second auxiliary mirror member 72b, so there is no need to use a polarizing beam splitter or a wave plate for polarization-combining the two beams, which reduces the number of parts required and reduces manufacturing costs.

[0113] Another exemplary configuration of a light-emitting module according to the second embodiment of the present disclosure will now be described with reference to Fig. 4. Fig. 4 is a top view schematically illustrating the configuration of a light-emitting module according to another exemplary second embodiment of the present disclosure. For simplicity, the first to fourth laser beams La to Ld shown in Fig. 4 are represented by thick lines with single arrows. The light-emitting module 100B2 shown in Fig. 4 differs from the light-emitting module 100B1 shown in Fig. 3 in the following three respects.

[0114] The first feature is that the light-emitting module 100B2 further includes, on the first mounting surfaces 12a, a plurality of third laser light sources 20c, a plurality of fourth laser light sources 20d, a plurality of third slow-axis collimating lenses 30c, a plurality of fourth slow-axis collimating lenses 30d, a plurality of third mirror members 40c, and a plurality of fourth mirror members 40d. The second feature is that the light-emitting module 100B2 includes, on the second mounting surfaces 12b, first to fourth auxiliary mirror members 72a to 72d, a first wave plate 74a, a second wave plate 74b, a first polarizing beam splitter 76a, and a second polarizing beam splitter 76b, instead of the first auxiliary mirror member 72a and the second auxiliary mirror member 72b shown in FIG. The third point is that the light-emitting module 100B2 includes a support base 10 having first and second mounting surfaces 12a and 12b with different dimensions compared to the light-emitting module 100B1. Due to the first point, the dimension of the first mounting surface 12a in the Z direction is larger. Due to the second point, the dimension of the second mounting surface 12b in the Z direction is larger.

[0115] The multiple third laser light sources 20c, the multiple third slow axis collimating lenses 30c, the multiple third mirror members 40c, the multiple fourth laser light sources 20d, the multiple fourth slow axis collimating lenses 30d, and the multiple fourth mirror members 40d are as described with reference to Figure 2, except for differences in arrangement.

[0116] On the same first mounting surface 12a, the third laser light source 20c and the fourth laser light source 20d are arranged in a mutually inverted relationship in the X direction. The same is true for the arrangements of the third slow-axis collimating lens 30c and the fourth slow-axis collimating lens 30d, and the arrangements of the third mirror member 40c and the fourth mirror member 40d.

[0117] As shown in FIG. 4 , each third laser light source 20c emits a third laser beam Lc in the first peak wavelength region in the −X direction. Each fourth laser light source 20d emits a fourth laser beam Ld in the second peak wavelength region in the +X direction. The emission directions of the third laser beam Lc and the fourth laser beam Ld are opposite to each other. Even if the optical axes of the third laser beam Lc and the fourth laser beam Ld are not all strictly parallel, this is permissible as long as the absolute value of the acute angle formed by these optical axes is 10° or less. On the same first mounting surface 12a, the first laser light source 20a and the third laser light source 20c are arranged adjacent to each other, and the second laser light source 20b and the fourth laser light source 20d are arranged adjacent to each other.

[0118] The emission directions of the first laser beam La and the third laser beam Lc are the same, and the emission directions of the second laser beam Lb and the fourth laser beam Ld are the same. The emission directions of the second laser beam Lb and the fourth laser beam Ld are opposite to the emission directions of the first laser beam La and the third laser beam Lc. Even if the optical axes of the first to fourth laser beams La to Ld are not all strictly parallel, this is permissible as long as the absolute value of the acute angle formed by any two optical axes is 10° or less. Here, it is assumed that the polarization directions of the first to fourth laser beams La to Ld emitted from the first to fourth laser light sources 20a to 20d, respectively, are all parallel to the Z direction.

[0119] Each third slow-axis collimating lens 30c collimates in the XZ plane the third laser beam Lc emitted from the corresponding third laser light source 20c. Each fourth slow-axis collimating lens 30d collimates in the XZ plane the fourth laser beam Ld emitted from the corresponding fourth laser light source 20d. On the same first mounting surface 12a, the first slow-axis collimating lens 30a and the third slow-axis collimating lens 30c are arranged adjacent to each other, and the second slow-axis collimating lens 30b and the fourth slow-axis collimating lens 30d are arranged adjacent to each other.

[0120] Each third mirror member 40c reflects the third laser beam Lc emitted from the corresponding third laser light source 20c in the +Z direction. Each fourth mirror member 40d reflects the fourth laser beam Ld emitted from the corresponding fourth laser light source 20d in the +Z direction.

[0121] The corresponding first mirror member 40a and third mirror member 40c arranged on each first mounting surface 12a are at different positions in the X direction, and the corresponding second mirror member 40b and fourth mirror member 40d arranged on each first mounting surface 12a are at different positions in the X direction. Therefore, the first laser beam La reflected by the first mirror member 40a can travel in the +Z direction without hitting the third mirror member 40c, and the second laser beam Lb reflected by the second mirror member 40b can travel in the +Z direction without hitting the fourth mirror member 40d.

[0122] The first wave plate 74a is a half-wave plate that changes the polarization direction of the third laser beam Lc traveling in the +Z direction from the X direction to the Y direction. The second wave plate 74b is a half-wave plate that changes the polarization direction of the fourth laser beam Ld traveling in the +Z direction from the X direction to the Y direction.

[0123] In the example shown in Fig. 4, the first wave plate 74a is positioned to receive the third laser beam Lc before it is reflected by the first auxiliary mirror member 72a, but this example is not limiting. The first wave plate 74a may be positioned to receive the third laser beam Lc after it has been reflected by the first auxiliary mirror member 72a. Similarly, in the example shown in Fig. 4, the second wave plate 74b is positioned to receive the fourth laser beam Ld before it is reflected by the second auxiliary mirror member 72b, but this example is not limiting. The second wave plate 74b may be positioned to receive the fourth laser beam Ld after it has been reflected by the second auxiliary mirror member 72b.

[0124] Alternatively, if the polarization directions of the first to fourth laser beams La to Ld emitted from the first to fourth laser light sources 20a to 20d are parallel to the Y direction, the first wave plate 74a and the second wave plate 74b may be positioned to receive the first laser beam La and the second laser beam Lb, respectively. In this case, the first wave plate 74a and the second wave plate 74b change the polarization direction of the first laser beam La and the second laser beam Lb traveling in the +Z direction from the Y direction to the X direction.

[0125] From the above, the following can be said about the first to fourth laser beams La to Ld and the first and second wave plates 74a and 74b: The first laser beam La or the third laser beam Lc passes through the first wave plate 74a, and after passing through, the polarization direction of the first laser beam La is orthogonal to the polarization direction of the third laser beam Lc. Similarly, the second laser beam Lb or the fourth laser beam Ld passes through the second wave plate 74b, and after passing through, the polarization direction of the second laser beam Lb is orthogonal to the polarization direction of the fourth laser beam Ld.

[0126] The first auxiliary mirror member 72a reflects the third laser beam Lc traveling in the +Z direction, changing the traveling direction of the third laser beam Lc to the −X direction. The second auxiliary mirror member 72b reflects the fourth laser beam Ld traveling in the +Z direction, changing the traveling direction of the fourth laser beam Ld to the +X direction.

[0127] The first polarizing beam splitter 76a, together with the first auxiliary mirror member 72a and the first wave plate 74a, polarization-combines the first laser beam La and the third laser beam Lc in the first peak wavelength region. Therefore, no difference due to wavelength dependency occurs, enabling highly efficient polarization-combining. Similarly, the second polarizing beam splitter 76b, together with the second auxiliary mirror member 72b and the second wave plate 74b, polarization-combines the second laser beam Lb and the fourth laser beam Ld in the second peak wavelength region. Therefore, no difference due to wavelength dependency occurs, enabling highly efficient polarization-combining. The polarization-combined first laser beam La and the third laser beam Lc and the polarization-combined second laser beam Lb and the fourth laser beam Ld are in an unpolarized state.

[0128] The third auxiliary mirror member 72c reflects the polarization-combined second laser beam Lb and fourth laser beam Ld and directs them toward the fourth auxiliary mirror member 72d. The fourth auxiliary mirror member 72d reflects the polarization-combined second laser beam Lb and fourth laser beam Ld and transmits the polarization-combined first laser beam La and third laser beam Lc. In this way, the fourth auxiliary mirror member 72d wavelength-combines the first to fourth laser beams La to Ld. The fourth auxiliary mirror member 72d may be, for example, a dichroic mirror.

[0129] The condenser lens 50 combines the following multiple laser beams that have been wavelength-combined and polarization-combined before entering the condenser lens 50 to form a combined beam. The multiple laser beams include a first laser beam La emitted from each first laser light source 20a and reflected by the corresponding first mirror member 40a, and a third laser beam Lc emitted from each third laser light source 20c and reflected by the corresponding third mirror member 40c. The multiple laser beams further include a second laser beam Lb emitted from each second laser light source 20b and reflected by the corresponding second mirror member 40b, and a fourth laser beam Ld emitted from each fourth laser light source 20d and reflected by the corresponding fourth mirror member 40d. The optical fiber 60 emits the combined beam to the outside of the light-emitting module 100B2.

[0130]

[0047] From the above, in the light-emitting module 100B2 according to the second embodiment, in addition to the first laser light source 20a and the second laser light source 20b that respectively emit the first laser beam La and the second laser beam Lb in different peak wavelength regions, the third laser light source 20c and the fourth laser light source 20d that respectively emit the third laser beam Lc and the fourth laser beam Ld in different peak wavelength regions are arranged on each of the plurality of first mounting surfaces 12a. Since the first to fourth laser light sources 20a to 20d are arranged on the same first mounting surface 12a, the number of the first to fourth laser light sources 20a to 20d mounted in the light-emitting module 100B2 can be further increased, and the output of the combined beam can be further increased.

[0131] Furthermore, in the light-emitting module 100B2 according to the second embodiment, the first polarizing beam splitter 76a, together with the first auxiliary mirror member 72a and the first wave plate 74a, polarization-combines the first laser beam La and the third laser beam Lc in the first peak wavelength region, and the second polarizing beam splitter 76b, together with the second auxiliary mirror member 72b and the second wave plate 74b, polarization-combines the second laser beam Lb and the fourth laser beam Ld in the second peak wavelength region. The fourth auxiliary mirror member 72d then wavelength-combines the polarization-combined first laser beam La and the third laser beam Lc and the polarization-combined second laser beam Lb and the fourth laser beam Ld. Because polarization combining is performed before wavelength combining, no differences due to wavelength dependency occur, enabling highly efficient polarization combining.

[0132] In this specification, the polarization directions of the first laser beam La and the third laser beam Lc in embodiment 2 are also referred to as the "first polarization direction" and the "second polarization direction," respectively, and the polarization directions of the second laser beam Lb and the fourth laser beam Ld in embodiment 2 are also referred to as the "third polarization direction" and the "fourth polarization direction," respectively.

[0133] (Modifications of Laser Light Sources) Modifications of the first to fourth laser light sources 20a to 20d will be described below with reference to FIGS. 5A to 5D.

[0134] Fig. 5A is a top view schematically showing the configuration of a modified example of the first laser light source 20a and the second laser light source 20b shown in Fig. 1A and Fig. 2. This modified example can also be applied to the third laser light source 20c and the fourth laser light source 20d shown in Fig. 2. The first laser light source 20a and the second laser light source 20b shown in Fig. 5A differ from the first laser light source 20a and the second laser light source 20b shown in Fig. 1A and Fig. 2 in the following three points.

[0135] 5A includes a common submount 21. The common submount 21 supports the first semiconductor laser element 22a and the second semiconductor laser element 22b, and is located between the first mounting surface 12a and the first semiconductor laser element 22a and the second semiconductor laser element 22b.

[0136] The second point is that the first laser light source 20a and the second laser light source 20b shown in FIG. 5A include a common lens support member 23 and a common fast-axis collimating lens 24. The common lens support member 23 has a shape that straddles the first semiconductor laser element 22a and the second semiconductor laser element 22b, and is supported by a common submount 21. The common fast-axis collimating lens 24 is supported by the common lens support member 23. The common fast-axis collimating lens 24 is located between the first semiconductor laser element 22a and the first slow-axis collimating lens 30a, and between the second semiconductor laser element 22b and the second slow-axis collimating lens 30b. The common fast-axis collimating lens 24 is further located between the first semiconductor laser element 22a and the first mirror member 40a, and between the second semiconductor laser element 22b and the second mirror member 40b.

[0137] 5A includes a corrective fast-axis collimating lens 25. The corrective fast-axis collimating lens 25 is located between the common fast-axis collimating lens 24 and the second slow-axis collimating lens 30b, and is located between the common fast-axis collimating lens 24 and the second mirror member 40b.

[0138] In the example shown in FIG. 5A , the common fast axis collimating lens 24 is designed to accurately collimate the first laser beam La in the first peak wavelength region. The corrective fast axis collimating lens 25, together with the common fast axis collimating lens 24, accurately collimates the second laser beam Lb in the second peak wavelength region. This example is not limiting, and the common fast axis collimating lens 24 may also be designed to accurately collimate the second laser beam Lb in the second peak wavelength region. In this case, the corrective fast axis collimating lens 25 is located between the common fast axis collimating lens 24 and the first slow axis collimating lens 30 a, and between the common fast axis collimating lens 24 and the first mirror member 40 a. The corrective fast axis collimating lens 25, together with the common fast axis collimating lens 24, accurately collimates the first laser beam La in the first peak wavelength region.

[0139] As shown in Fig. 5A , the first semiconductor laser element 22a and the second semiconductor laser element 22b are supported by a common submount 21, making it easy to arrange the first semiconductor laser element 22a and the second semiconductor laser element 22b together on the first mounting surface 12a via the common submount 21. In the configuration shown in Fig. 5A , a common fast axis collimating lens 24 is supported by a common lens support member 23, and the common lens support member 23 is supported by a common submount 21. Alternatively, a configuration may be possible in which the first fast axis collimating lens 24a and the second fast axis collimating lens 24b shown in Fig. 1A are supported by a first lens support member 23a and a second lens support member 23b, respectively, and the first lens support member 23a and the second lens support member 23b are supported by a common submount 21. However, the configuration shown in Fig. 5A is easier to fabricate.

[0140] Fig. 5B is a top view schematically showing the configuration of a modified example of the first laser light source 20a and the third laser light source 20c shown in Fig. 4. This modified example can also be applied to the second laser light source 20b and the fourth laser light source 20d shown in Fig. 4. The first laser light source 20a and the third laser light source 20c shown in Fig. 5B differ from the first laser light source 20a and the third laser light source 20c shown in Fig. 4 in the following two points.

[0141] 5B includes a common submount 21. The common submount 21 supports the first semiconductor laser element 22a and the third semiconductor laser element 22c, and is located between the first mounting surface 12a and the first semiconductor laser element 22a and the third semiconductor laser element 22c.

[0142] The second point is that the first laser light source 20a and the third laser light source 20c shown in FIG. 5B include a common lens support member 23 and a common fast-axis collimating lens 24. The common lens support member 23 and the common fast-axis collimating lens 24 are as described with reference to FIG. 5A . However, the common lens support member 23 has a shape that straddles the first laser light source 20a and the third laser light source 20c. The common fast-axis collimating lens 24 is located between the first semiconductor laser element 22a and the first slow-axis collimating lens 30a, and between the third semiconductor laser element 22c and the third slow-axis collimating lens 30c. The common fast-axis collimating lens 24 is further located between the first semiconductor laser element 22a and the first mirror member 40a, and between the third semiconductor laser element 22c and the third mirror member 40c. The common fast axis collimating lens 24 is designed to accurately collimate the first laser beam La and the third laser beam Lc in the first peak wavelength region.

[0143] As shown in Fig. 5B , the first semiconductor laser element 22 a and the third semiconductor laser element 22 c are supported by a common submount 21, and therefore it is easy to arrange the first semiconductor laser element 22 a and the third semiconductor laser element 22 c together on the first mounting surface 12 a via the common submount 21. In the configuration shown in Fig. 5B , similar to the configuration shown in Fig. 5A , the common fast axis collimating lens 24 is supported by a common lens support member 23, and the common lens support member 23 is supported by a common submount 21. Therefore, the configuration shown in Fig. 5B is easy to fabricate.

[0144] 5B, the first semiconductor laser element 22a and the third semiconductor laser element 22c emit the first laser beam La and the third laser beam Lc in the first peak wavelength region, respectively, and therefore, unlike the example shown in FIG. 5A, there is no need to provide the fast axis collimator lens 25 for correction.

[0145] Fig. 5C is a top view schematically showing the configuration of another modified example of the first laser light source 20a and the second laser light source 20b shown in Fig. 1A and Fig. 2. This modified example can also be applied to the third laser light source 20c and the fourth laser light source 20d shown in Fig. 2, the first laser light source 20a and the third laser light source 20c shown in Fig. 4, and the second laser light source 20b and the fourth laser light source 20d shown in Fig. 4.

[0146] The first laser light source 20a and the second laser light source 20b shown in FIG. 5C differ from the first laser light source 20a and the second laser light source 20b shown in FIGS. 1A and 2 in that the first laser light source 20a is housed in a first package 80a, and the second laser light source 20b is housed in a second package 80b. In addition to the first laser light source 20a, a first slow axis collimating lens 30a may also be housed in the first package 80a. In addition to the second laser light source 20b, a second slow axis collimating lens 30b may also be housed in the second package 80b. The dashed lines in FIG. 5C represent the components in the first package 80a and the components in the second package 80b. Thus, the light-emitting module 100A1 shown in FIG. 1A and the light-emitting module 100A2 shown in FIG. 2 may further include a first package 80a and a second package 80b.

[0147] The first laser light source 20a and the second laser light source 20b are sealed, more specifically, hermetically sealed, in a first package 80a and a second package 80b, respectively. The effect of the hermetically sealed package increases as the wavelengths of the first laser beam La and the second laser beam Lb become shorter. This is because, in a configuration where the emission surfaces of the first semiconductor laser element 22a and the second semiconductor laser element 22b included in the first laser light source 20a and the second laser light source 20b are exposed to the outside air without being hermetically sealed, the shorter the wavelengths of the first laser beam La and the second laser beam Lb, the more likely it is that the emission surfaces will deteriorate due to dust collection during operation.

[0148] Fig. 5D is a top view schematically showing the configuration of yet another modified example of the first laser light source 20a and the second laser light source 20b shown in Fig. 1A and Fig. 2. This modified example can also be applied to the third laser light source 20c and the fourth laser light source 20d shown in Fig. 2, the first laser light source 20a and the third laser light source 20c shown in Fig. 4, the second laser light source 20b and the fourth laser light source 20d shown in Fig. 4, the first laser light source 20a and the second laser light source 20b shown in Fig. 5A, and the first laser light source 20a and the third laser light source 20c shown in Fig. 5B.

[0149] The first laser light source 20a and the second laser light source 20b shown in FIG. 5D differ from the first laser light source 20a and the second laser light source 20b shown in FIGS. 1A and 2 in that the first laser light source 20a and the second laser light source 20b are housed in a common package 80. This reduces the volume occupied by the package in the light-emitting modules 100A1 and 100A2, thereby saving space. Furthermore, using the common package 80 reduces the number of components in the package, thereby reducing costs. In addition to the first laser light source 20a and the second laser light source 20b, the first slow-axis collimating lens 30a and the second slow-axis collimating lens 30b may also be housed in the common package 80. The dashed lines in FIG. 5D represent the components within the package 80. Thus, the light-emitting module 100A1 shown in FIG. 1A and the light-emitting module 100A2 shown in FIG. 2 may further include a common package 80.

[0150] By disposing the common package 80 containing the first laser light source 20a and the second laser light source 20b on the first mounting surface 12a, it becomes easy to dispose the first laser light source 20a and the second laser light source 20b together on the first mounting surface 12a via the bottom surface of the package 80. Furthermore, it becomes easy to seal the first laser light source 20a and the second laser light source 20b together using the common package 80, more specifically, to hermetically seal them.

[0151] 2, the first laser light source 20a and the second laser light source 20b may be housed in a common package 80, and the third laser light source 20c and the fourth laser light source 20d may be housed in another common package 80. In this way, the light-emitting module 100A2 shown in FIG. 2 may further include the common package 80 and the other common package 80.

[0152] 4, the first laser light source 20a and the third laser light source 20c may be housed in a common package 80, and the second laser light source 20b and the fourth laser light source 20d may be housed in another common package 80. In this way, the light-emitting module 100B2 shown in FIG. 4 may further include the common package 80 and another common package 80.

[0153] In this specification, a configuration including one or more laser light sources and a package that houses the one or more laser light sources is also referred to as a "light emitting device."

[0154] (DDL Device) Next, a configuration example of a DDL device according to an embodiment of the present disclosure will be described with reference to FIG. 6 . FIG. 6 is a diagram schematically illustrating the configuration of a DDL device according to an exemplary embodiment of the present disclosure. The DDL device 1000 shown in FIG. 6 includes a plurality of light-emitting modules 100A1, a processing head 300, and an optical transmission fiber 250 that connects the plurality of light-emitting modules 100A1 to the processing head 300. Any of the light-emitting modules 100A2, 100B1, and 100B2 shown in FIGS. 2 to 4 may be used in place of the light-emitting module 100A1 shown in FIGS. 1A and 1B .

[0155] 6, the number of light-emitting modules 100A1 is four, but is not limited to this number. The number of light-emitting modules 100A1 may be one, two, three, or five or more.

[0156] The number of first laser light sources 20a and second laser light sources 20b included in each light-emitting module 100A1 is determined according to the required optical output or irradiance. The peak wavelength ranges of the first laser beam La and the second laser beam Lb emitted from the first laser light source 20a and the second laser light source 20b, respectively, can also be selected according to the material to be processed. When processing metal parts made of copper, brass, or aluminum, the peak wavelength ranges of the first laser beam La and the second laser beam Lb can be, for example, in the range of 350 nm to 550 nm. The effects of the present invention can also be achieved when using a combined beam whose peak wavelength range is outside the range of 350 nm to 550 nm.

[0157] In the example shown in FIG. 6 , multiple optical fibers 60 extending from multiple light-emitting modules 100A1 are coupled to an optical transmission fiber 250 by an optical multiplexer 230. The optical multiplexer 230 may be, for example, a tapered fiber bundle (TFB). The processing head 300 focuses and irradiates the laser beams emitted from the output end faces of the optical fibers 60 onto the target 400. When one DDL device 1000 includes M light-emitting modules 100A1, each of which includes N first laser light sources 20a and N second laser light sources 20b, if the optical output of one first laser light source 20a is P watts and the optical output of one second laser light source 20b is P watts, a laser beam having an optical output of up to P×2N×M watts can be focused onto the target 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=11, and M=12, an optical output of over 5 kilowatts can be achieved.

[0158] 7A and 7B, a configuration example of the first laser light source 20a shown in Fig. 1A will be described. The second to fourth laser light sources 20b to 20d also have the same structure as the first laser light source 20a.

[0159] Fig. 7A is an exploded perspective view of the first laser light source 20a. Fig. 7B is a cross-sectional view of the first laser light source 20a parallel to the XY plane. The components of the first laser light source 20a will be described below.

[0160] As shown in FIG. 7A , the first submount 21a 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 first semiconductor laser element 22a and the first lens support member 23a are bonded to the first submount 21a with an inorganic bonding material. The metal film provided on the upper surface 21us may also be used to supply power to the first semiconductor laser element 22a. The metal film provided on the lower surface 21Ls improves the bonding strength when the support base 10 and the first laser light source 20a shown in FIG. 1A are bonded via an inorganic bonding material. The metal films provided on the upper surface 21us and the lower surface 21Ls also help transfer heat generated by the first semiconductor laser element 22a during operation to the support base 10 via the first submount 21a. The first submount 21a can be formed, for example, like the support base 10, from the above-mentioned ceramics, metal materials, or metal matrix composite materials.

[0161] As shown in FIG. 7A , the first semiconductor laser element 22a is supported by the upper surface 21us of the first submount 21a. The first semiconductor laser element 22a has an emission surface 22s, one of two end surfaces intersecting the X direction, and emits laser light in the −X direction from the emission surface 22s. The laser light spreads relatively quickly in the XY plane and relatively slowly in the XZ plane. When not collimated, the spot of the laser light has an elliptical shape in the far field in the YZ plane, with the major axis in the Y direction and the minor axis in the Z direction.

[0162] The first semiconductor laser element 22a can emit violet, blue, green, or red laser light in the visible region, or infrared or ultraviolet laser light in the invisible region. The peak wavelength of the 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 peak wavelength of the blue light is preferably in the range of 420 nm to 495 nm, and more preferably in the range of 440 nm to 475 nm. The peak wavelength of the green light is preferably in the range of 495 nm to 570 nm, and more preferably in the range of 510 nm to 550 nm. The peak wavelength of the 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.

[0163] The first semiconductor laser element 22a emitting violet, blue, and green laser beams may be a laser diode containing a nitride semiconductor material, such as GaN, InGaN, or AlGaN. The first semiconductor laser element 22a emitting red laser beams may be a laser diode containing an InAlGaP-based, GaInP-based, GaAs-based, or AlGaAs-based semiconductor material.

[0164] As shown in FIG. 7A , the first lens support member 23a is supported by the upper surface 21us of the first submount 21a. The first lens support member 23a has two columnar portions 23a1 and a connecting portion 23a2 located between the two columnar portions 23a1 and connecting the two columnar portions 23a1. The two columnar portions 23a1 are located on both sides of the first semiconductor laser element 22a, and the connecting portion 23a2 is located above the emission surface 22s of the first semiconductor laser element 22a. The first lens support member 23a supports the first fast axis collimating lens 24a by the end faces 23as of the two columnar portions 23a1. The first lens support member 23a is located so as to straddle the first semiconductor laser element 22a and does not prevent the laser light emitted from the first semiconductor laser element 22a from entering the first fast axis collimating lens 24a.

[0165] The first lens support member 23a may be formed of, for example, the ceramics described above, similar to the support base 10 shown in FIG. 1A. The first lens support member 23a may be formed of, for example, the optically transparent material described above, similar to the first slow axis collimating lens 30a shown in FIG. 1A. The first lens support member 23a may be formed of, for example, at least one alloy selected from the group consisting of Kovar and CuW. The first lens support member 23a may be formed of, for example, Si.

[0166] As shown in FIG. 7A, the first fast axis collimating lens 24a may be, for example, a cylindrical lens having a uniform cross-sectional shape in the Z direction. The first fast axis collimating lens 24a has a flat surface on the light incident side and a convex surface on the light exit side. The convex surface has a curvature in the XY plane. The focal point of the first fast axis collimating lens 24a approximately coincides with the center of the light-emitting point on the exit surface 22s of the first semiconductor laser element 22a. As shown in FIG. 7B, the first fast axis collimating lens 24a collimates, in the XY plane, the laser light emitted in the −X direction from the exit surface 22s of the first semiconductor laser element 22a. As a result, the first laser beam La collimated in the XY plane is emitted from the first laser light source 20a. The region surrounded by the dashed line in FIG. 7B is a region where the intensity of the first laser beam La is 1 / e of its peak intensity. ２ The first fast axis collimating lens 24a may be formed from the above-mentioned optically transparent material, for example, similar to the first slow axis collimating lens 30a shown in FIG. 1A.

[0167] The first fast axis collimating lens 24a supported by the first lens support member 23a is located near the emission surface 22s of the first semiconductor laser element 22a. Therefore, the first fast axis collimating lens 24a can collimate the laser light before it diverges significantly. This helps to make the first fast axis collimating lens 24a compact.

[0168] Instead of the first fast-axis collimating lens 24a, a collimating lens that collimates the laser light emitted from the first semiconductor laser element 22a not only in the XY plane but also in the XZ plane may be used. In this case, the first slow-axis collimating lens 30a does not need to be provided in the light-emitting module 100A1 shown in Figures 1A and 1B. The same applies to the second slow-axis collimating lens 30b.

[0169] 8A and 8B, a configuration example of a first light-emitting device including a first laser light source 20a and a first package 80a that houses the first laser light source 20a will be described below. The first laser light source 20a may be read as a second laser light source 20b, the first package 80a may be read as a second package 80b, and the first light-emitting device may be read as a second light-emitting device.

[0170] 8A and 8B are a perspective view and a cross-sectional view, respectively, schematically illustrating an example configuration of a first light-emitting device. The first light-emitting device 200a shown in FIGS. 8A and 8B includes a first laser light source 20a, mirror members 26a1 and 26a2, and a first package 80a. The first package 80a includes a substrate 81a having a mounting surface 81as, a frame 82a having an upper surface 82as, and a cover 83a having an upper surface 83as1 and a lower surface 83as2.

[0171] As shown in FIG. 8B , the first laser light source 20a and the mirror member 26a1 are mounted on the mounting surface 81as of the substrate 81a. The frame 82a is positioned around the mounting surface 81as of the substrate 81a and surrounds the first laser light source 20a and the mirror member 26a1. As shown in FIG. 8A , conductive regions 82ac1 and 82ac2 for supplying power to the first laser light source 20a are provided on the upper surface 82as of the frame 82a. The cover 83a is supported by the upper surface 82as of the frame 82a. A light-shielding film 83f for reducing stray light is provided on the lower surface 83as2 of the cover 83a, except for the region that transmits the first laser beam La. The mirror member 26a2 is supported by the upper surface 83as1 of the cover 83a.

[0172] In the first light-emitting device 200a, the mirror member 26a1 reflects the first laser beam La emitted from the first laser light source 20a in a direction away from the mounting surface 81as, as shown in FIG. 8B . More specifically, the direction away from the mounting surface 81as is the +Y direction, which is the normal direction of the mounting surface 81as. The mirror member 26a2 reflects the first laser beam La, which is reflected by the mirror member 26a1 and transmitted through the cover 83a, in the −X direction. Even if the first laser light source 20a and the mirror member 26a1 are not precisely positioned on the mounting surface 81as, the first laser beam La can be accurately directed in the −X direction by appropriately adjusting the position and orientation of the mirror member 26a2. In this way, the first light-emitting device 200a emits the first laser beam La in the −X direction. In the first light emitting device 200a, the first laser light source 20a is sealed, more specifically, hermetically sealed, by a substrate 81a, a frame 82a, and a cover 83a.

[0173] The substrate 81a may be formed of at least one metal material selected from the group consisting of Cu, Al, and Ag. The frame 82a may be formed of a ceramic material selected from the group consisting of AlN, SiN, SiC, and alumina. The cover 83a may be formed of at least one light-transmitting material selected from the group consisting of glass, silicon, quartz, synthetic quartz, sapphire, transparent ceramics, silicone resin, and plastic. The mirror members 26a1 and 26a2 may be formed of, for example, a dielectric multilayer film or a metal material.

[0174] 8A and 8B , when the first package 80a accommodates not only the first laser light source 20a but also other laser light sources, the first package 80a is appropriately modified so that not only the first laser beam La but also other laser beams emitted from the other laser light sources are emitted in the −X direction. For example, the dimension of the first package 80a in the Z direction may be enlarged, two mirror members may be separately provided to reflect the other laser beams emitted from the other laser light sources, a region that transmits the other laser beams may be separately provided in the cover 83a, and two conductive regions may be separately provided to supply power to the other laser light sources.

[0175] Details of the first light-emitting device 200a shown in Figures 8A and 8B are disclosed, for example, in U.S. Patent Application Publication No. 2024 / 0047946, the entire disclosure of which is incorporated herein by reference.

[0176] Next, with reference to FIGS. 9A and 9B , another configuration example of a first light-emitting device including a first laser light source 20a and a first package 80a that houses the first laser light source 20a will be described. FIGS. 9A and 9B are a perspective view and a cross-sectional view, respectively, that schematically illustrate another configuration example of a first light-emitting device. The first light-emitting device 200a shown in FIGS. 9A and 9B includes a first laser light source 20a and a first package 80a. The first package 80a includes a base 84a, a lead holding member 85a, a pair of leads 86a for supplying power to the first laser light source 20a, and a cover 87a. The base 84a includes a bottom 84a1 having a mounting surface 84as1 and a sidewall 84a2 having an upper surface 84as2. The sidewall 84a2 includes a light-transmitting portion 84at, a cap 84ac, and a reinforcing member 84ar.

[0177] The first laser light source 20a is mounted on the mounting surface 84as1 of the bottom 84a1. The sidewall 84a2 is located around the mounting surface 84as1 of the bottom 84a1 and surrounds the first laser light source 20a. The light-transmitting portion 84at is provided on the sidewall 84a2 via the cap 84ac and transmits the first laser beam La emitted from the first laser light source 20a. The lead holding member 85a is joined to the sidewall 84a2. A pair of leads 86a are held by the lead holding member 85a and penetrate the lead holding member 85a and the sidewall 84a2. At least central portions of the pair of leads 86a are made of copper. The thermal expansion coefficient of the lead holding member 85a is equal to or greater than that of the sidewall 84a2 and equal to or less than that of the pair of leads 86a. The cover 87a is supported by the upper surface 84as2 of the side wall 84a2 via the reinforcing member 84ar.

[0178] 9B , the first light-emitting device 200a emits a first laser beam La from the first laser light source 20a through the light-transmitting portion 84at of the side wall 84a2. Because at least the central portions of the pair of leads 86a are formed from copper, which has high electrical conductivity, a large current can be passed through the pair of leads 86a, making it possible to increase the output of the first laser beam La emitted from the first laser light source 20a to 10 W or more. In the first light-emitting device 200a, the first laser light source 20a is sealed, more specifically, hermetically sealed, by the base 84a, the lead holding member 85a, the pair of leads 86a, and the cover 87a.

[0179] Because the thermal expansion coefficient of the lead holding member 85a is approximately intermediate between that of the sidewall 84a2 and that of the pair of leads 86a, the lead holding member 85a can function as a buffer. Therefore, even if thermal stress occurs in the sidewall 84a2 when the first light-emitting device 200a is driven, the lead holding member 85a can continue to seal the gap between each lead 86a and the sidewall 84a2 from the outside. As a result, the durability of the first package 80a against thermal stress is improved.

[0180] The bottom portion 84a1 may be formed, for example, from a metal material with high thermal conductivity. This metal material may be, for example, copper, iron, a copper alloy, or an iron alloy. The sidewall 84a2 may be formed, for example, from kovar. Kovar is an alloy primarily composed of iron, nickel, and cobalt. The cap 84ac may be formed, for example, from an Fe-Ni alloy. The light-transmitting portion 84at may be formed, for example, from borosilicate glass. The reinforcing member 84ar may be formed, for example, from the same material as the sidewall 84a2. The lead holding member 85a may be formed, for example, from mild steel, which is iron with a carbon content of 0.05% to 0.3%. Portions of the pair of leads 86a other than their central portions may be formed from copper or a material other than copper. The cover 87a may be formed, for example, from the same material as the sidewall 84a2.

[0181] 9A and 9B , when the first package 80a accommodates not only the first laser light source 20a but also other laser light sources, the first package 80a is appropriately modified so that not only the first laser beam La but also other laser beams emitted from the other laser light sources are emitted in the −X direction. For example, the dimension of the first package 80a in the Z direction may be enlarged, another light-transmitting portion that transmits the other laser beam may be separately provided on the side wall 84a2, and another pair of leads may be separately provided for supplying power to the other laser light sources.

[0182] Details of the first light-emitting device 200a shown in Figures 9A and 9B are disclosed, for example, in U.S. Patent Application Publication No. 2021 / 0203127, the entire disclosure of which is incorporated herein by reference.

[0183] The present disclosure includes a light emitting module as described in the following items.

[0184] [Item 1] A support base having a plurality of mounting surfaces arranged in a first direction, the heights of the plurality of mounting surfaces from a reference plane parallel to the first direction decreasing along the first direction; a plurality of first laser light sources, one or more of which are arranged on each of the plurality of mounting surfaces, each emitting a first laser beam in a first peak wavelength region in a second direction intersecting the first direction; a plurality of second laser light sources, one or more of which are arranged on each of the plurality of mounting surfaces, each emitting a second laser beam in a second peak wavelength region different from the first peak wavelength region in a third direction intersecting the first direction; a plurality of first mirror members, one or more of which are arranged on each of the plurality of mounting surfaces, each reflecting the first laser beam emitted from the corresponding first laser light source in the first direction; and a plurality of second mirror members, one or more of which are arranged on each of the plurality of mounting surfaces, each reflecting the second laser beam emitted from the corresponding second laser light source in the first direction. a condenser lens that combines a plurality of laser beams, including the first laser beam emitted from each of the plurality of first laser light sources and reflected by a corresponding first mirror member, and the second laser beam emitted from each of the plurality of second laser light sources and reflected by a corresponding second mirror member.

[0185] [Item 2] The light-emitting module according to item 1, wherein a wavelength width of a wavelength region sandwiched between the first peak wavelength region and the second peak wavelength region is 5 nm or more and 100 nm or less.

[0186] [Item 3] The light-emitting module according to item 1 or 2, wherein the plurality of mounting surfaces are arranged in a stepped manner in the first direction, and a step between two adjacent mounting surfaces among the plurality of mounting surfaces is larger than 80% of the beam diameter of each of the first laser beam and the second laser beam and is not more than four times the beam diameter.

[0187] [Item 4] The laser beam source further comprises: a plurality of third laser light sources, one or more of which are arranged on each of the plurality of mounting surfaces, each emitting a third laser beam in the first peak wavelength region in a fourth direction intersecting the first direction; a plurality of fourth laser light sources, one or more of which are arranged on each of the plurality of mounting surfaces, each emitting a fourth laser beam in the second peak wavelength region in a fifth direction intersecting the first direction; a plurality of third mirror members, one or more of which are arranged on each of the plurality of mounting surfaces, each reflecting the third laser beam emitted from the corresponding third laser light source in the first direction; and a plurality of fourth mirror members, one or more of which are arranged on each of the plurality of mounting surfaces, each reflecting the fourth laser beam emitted from the corresponding fourth laser light source in the first direction, 4. The light-emitting module according to claim 1, wherein the plurality of laser beams combined by the focusing lens further include the third laser beam emitted from each of the plurality of third laser light sources and reflected by a corresponding third mirror member, and the fourth laser beam emitted from each of the plurality of fourth laser light sources and reflected by a corresponding fourth mirror member.

[0188] [Item 5] The light-emitting module according to any one of Items 1 to 3, wherein the second direction and the third direction are the same direction, and each of the plurality of second mirror members is a dichroic mirror that transmits the first laser beam and reflects the second laser beam.

[0189] [Item 6] The light emitting module according to Item 5, wherein the corresponding first laser light source and the corresponding second laser light source arranged on each of the plurality of mounting surfaces are arranged adjacent to each other.

[0190] [Item 7] The light emitting module according to item 5 or 6, further comprising a common package that houses a corresponding first laser light source and a corresponding second laser light source arranged on each of the plurality of mounting surfaces.

[0191] [Item 8] The light emitting module according to any one of Items 5 to 7, further comprising a common submount positioned between each of the plurality of mounting surfaces and the corresponding first laser light source and the corresponding second laser light source.

[0192] [Item 9] The light emitting module according to any one of Items 5 to 8, further comprising a common fast axis collimating lens positioned on each of the plurality of mounting surfaces between the corresponding first laser light source and the corresponding first mirror member, and between the corresponding second laser light source and the corresponding second mirror member.

[0193] [Item 10] The light emitting module according to Item 9, further comprising a corrective fast axis collimating lens positioned on each of the plurality of mounting surfaces between the corresponding first mirror member and the common fast axis collimating lens, or between the corresponding second mirror member and the common fast axis collimating lens.

[0194] [Item 11] The light-emitting module described in Item 4, wherein the second direction and the third direction are the same direction, the fourth direction and the fifth direction are opposite directions to the second direction and the third direction, each of the plurality of second mirror members is a dichroic mirror that transmits the first laser beam and reflects the second laser beam, and each of the plurality of fourth mirror members is a dichroic mirror that transmits the third laser beam and reflects the fourth laser beam.

[0195] [Item 12] The light emitting module according to item 11, further comprising: a wave plate through which the first laser beam and the second laser beam, or the third laser beam and the fourth laser beam, pass, wherein after the wave plate has passed through, a first polarization direction of the first laser beam and the second laser beam and a second polarization direction of the third laser beam and the fourth laser beam are orthogonal to each other; and a polarizing beam splitter that combines the first laser beam and the second laser beam having the first polarization direction and the third laser beam and the fourth laser beam having the second polarization direction before the plurality of laser beams enter the focusing lens.

[0196] [Item 13] The light emitting module according to item 11 or 12, further comprising: a common package that houses a corresponding first laser light source and a corresponding second laser light source that are arranged on each of the plurality of mounting surfaces; and another common package that houses a corresponding third laser light source and a corresponding fourth laser light source that are arranged on each of the plurality of mounting surfaces.

[0197] [Item 14] The light emitting module according to any one of items 1 to 3, wherein the second direction and the third direction are opposite to each other.

[0198] [Item 15] The light-emitting module described in Item 4, wherein the second direction and the fourth direction are the same direction, the third direction and the fifth direction are opposite directions to the second direction and the fourth direction, corresponding first mirror members and corresponding third mirror members arranged on each of the plurality of mounting surfaces are at different positions in the second direction, and corresponding second mirror members and corresponding fourth mirror members arranged on each of the plurality of mounting surfaces are at different positions in the third direction.

[0199] [Item 16] The light emitting module described in Item 15 further comprises: a first wave plate through which the first laser beam or the third laser beam passes, and after the first wave plate, a first polarization direction of the first laser beam and a second polarization direction of the third laser beam are orthogonal; a first polarizing beam splitter that combines the first laser beam having the first polarization direction and the third laser beam having the second polarization direction; a second wave plate through which the second laser beam or the fourth laser beam passes, and after the second wave plate, a third polarization direction of the second laser beam and a fourth polarization direction of the fourth laser beam are orthogonal; and a second polarizing beam splitter that combines the second laser beam having the third polarization direction and the fourth laser beam having the fourth polarization direction.

[0200] [Item 17] The light emitting module according to item 15 or 16, further comprising: a common package that houses a corresponding first laser light source and a corresponding third laser light source arranged on each of the plurality of mounting surfaces; and another common package that houses a corresponding second laser light source and a corresponding fourth laser light source arranged on each of the plurality of mounting surfaces.

[0201] The light emitting device of the present disclosure can be used to combine multiple laser beams to produce a high-power laser beam, and can be used in industrial fields where a high-power laser light source is required, such as cutting, drilling, local heat treatment, surface treatment, metal welding, and 3D printing of various materials.

[0202] 10: Support base 12a: First mounting surface 12b: Second mounting surface 20a to 20d: First to fourth laser light sources 21: Submounts 21a to 21d: First to fourth submounts 22a to 22d: First to fourth semiconductor laser elements 23: Lens support member 23a to 23d: First to fourth lens support members 24, 25: Fast axis collimating lenses 24a to 24d: First to fourth fast axis collimating lenses 26a1, 26a2: Mirror members 30a to 30d: First to fourth slow axis collimating lenses 40a to 40d: First to fourth mirror members 50: Condenser lens 50a: Fast axis condenser lens 50b: Slow axis condenser lens 60: Optical fiber 62: Support member 72: Auxiliary mirror member 72a to 72d: first to fourth auxiliary mirror members 74: wave plate 74a, 74b: first and second wave plates 76: polarizing beam splitter 76a, 76b: first and second polarizing beam splitters 80: package 80a, 80b: first and second packages 81a: substrate 82a: frame 82ac1, 82ac2: conductive region 83a: cover 83f: light-shielding film 84a: base 84a1: bottom 84a2: side wall 84ac: cap 84ar: reinforcing member 84at: light-transmitting portion 85a: lead holding member 86a: lead 87a: cover 100A1, 100A2, 100B1, 100B2: light-emitting module 200a: first light-emitting device 230: optical multiplexer 250: Optical transmission fiber 300: Processing head 400: Object 1000: DDL device La to Ld: First to fourth laser beams Ref: Reference plane

Claims

1. A support base having a plurality of mounting surfaces arranged in a first direction, the heights of the plurality of mounting surfaces from a reference plane parallel to the first direction decreasing along the first direction; a plurality of first laser light sources, one or more of which are arranged on each of the plurality of mounting surfaces, each emitting a first laser beam in a first peak wavelength region in a second direction intersecting the first direction; a plurality of second laser light sources, one or more of which are arranged on each of the plurality of mounting surfaces, each emitting a second laser beam in a second peak wavelength region different from the first peak wavelength region in a third direction intersecting the first direction; a plurality of first mirror members, one or more of which are arranged on each of the plurality of mounting surfaces, each reflecting the first laser beam emitted from the corresponding first laser light source in the first direction; and a plurality of second mirror members, one or more of which are arranged on each of the plurality of mounting surfaces, each reflecting the second laser beam emitted from the corresponding second laser light source in the first direction. a condenser lens that combines a plurality of laser beams, including the first laser beam emitted from each of the plurality of first laser light sources and reflected by a corresponding first mirror member, and the second laser beam emitted from each of the plurality of second laser light sources and reflected by a corresponding second mirror member.

2. The light-emitting module according to claim 1, wherein the wavelength width of the wavelength region sandwiched between the first peak wavelength region and the second peak wavelength region is 5 nm or more and 100 nm or less.

3. The light-emitting module described in claim 1 or 2, wherein the plurality of mounting surfaces are arranged in a stepped pattern in the first direction, and the step between two adjacent mounting surfaces among the plurality of mounting surfaces is greater than 80% of the beam diameter of each of the first laser beam and the second laser beam, and is not more than four times the beam diameter.

4. The laser device further comprises: a plurality of third laser light sources, one or more of which are arranged on each of the plurality of mounting surfaces, each emitting a third laser beam in the first peak wavelength region in a fourth direction intersecting the first direction; a plurality of fourth laser light sources, one or more of which are arranged on each of the plurality of mounting surfaces, each emitting a fourth laser beam in the second peak wavelength region in a fifth direction intersecting the first direction; a plurality of third mirror members, one or more of which are arranged on each of the plurality of mounting surfaces, each reflecting the third laser beam emitted from the corresponding third laser light source in the first direction; and a plurality of fourth mirror members, one or more of which are arranged on each of the plurality of mounting surfaces, each reflecting the fourth laser beam emitted from the corresponding fourth laser light source in the first direction, 4. The light-emitting module according to claim 1, wherein the plurality of laser beams combined by the focusing lens further include the third laser beam emitted from each of the plurality of third laser light sources and reflected by a corresponding third mirror member, and the fourth laser beam emitted from each of the plurality of fourth laser light sources and reflected by a corresponding fourth mirror member.

5. An optical emission module described in any one of claims 1 to 3, wherein the second direction and the third direction are the same direction, and each of the plurality of second mirror members is a dichroic mirror that transmits the first laser beam and reflects the second laser beam.

6. The light-emitting module according to claim 5, wherein the corresponding first laser light source and the corresponding second laser light source arranged on each of the plurality of mounting surfaces are arranged adjacent to each other.

7. The light emitting module according to claim 5 or 6, further comprising a common package that houses a corresponding first laser light source and a corresponding second laser light source arranged on each of the plurality of mounting surfaces.

8. The light-emitting module according to any one of claims 5 to 7, further comprising a common submount positioned between each of the plurality of mounting surfaces and the corresponding first laser light source and the corresponding second laser light source.

9. An optical emission module as described in any one of claims 5 to 8, further comprising a common fast axis collimating lens positioned between the corresponding first laser light source and the corresponding first mirror member, and between the corresponding second laser light source and the corresponding second mirror member, on each of the plurality of mounting surfaces.

10. The light-emitting module described in claim 9, further comprising a corrective fast axis collimating lens located on each of the plurality of mounting surfaces between the corresponding first mirror member and the common fast axis collimating lens, or between the corresponding second mirror member and the common fast axis collimating lens.

11. The light-emitting module described in claim 4, wherein the second direction and the third direction are the same direction, the fourth direction and the fifth direction are opposite directions to the second direction and the third direction, each of the plurality of second mirror members is a dichroic mirror that transmits the first laser beam and reflects the second laser beam, and each of the plurality of fourth mirror members is a dichroic mirror that transmits the third laser beam and reflects the fourth laser beam.

12. The light emitting module of claim 11, further comprising: a wave plate through which the first laser beam and the second laser beam, or the third laser beam and the fourth laser beam, pass, such that after passing through the wave plate, a first polarization direction of the first laser beam and the second laser beam and a second polarization direction of the third laser beam and the fourth laser beam are orthogonal to each other; and a polarizing beam splitter that combines the first laser beam and the second laser beam having the first polarization direction and the third laser beam and the fourth laser beam having the second polarization direction before the multiple laser beams are incident on the focusing lens.

13. The light emitting module according to claim 11 or 12, further comprising: a common package accommodating a corresponding first laser light source and a corresponding second laser light source arranged on each of the plurality of mounting surfaces; and another common package accommodating a corresponding third laser light source and a corresponding fourth laser light source arranged on each of the plurality of mounting surfaces.

14. The light emitting module according to any one of claims 1 to 3, wherein the second direction and the third direction are opposite to each other.

15. The light-emitting module described in claim 4, wherein the second direction and the fourth direction are the same direction, the third direction and the fifth direction are opposite directions to the second direction and the fourth direction, corresponding first mirror members and corresponding third mirror members arranged on each of the plurality of mounting surfaces are at different positions in the second direction, and corresponding second mirror members and corresponding fourth mirror members arranged on each of the plurality of mounting surfaces are at different positions in the third direction.

16. The light emitting module of claim 15, further comprising: a first wave plate through which the first laser beam or the third laser beam passes, and through which, after the first wave plate has passed, the first polarization direction of the first laser beam and the second polarization direction of the third laser beam are orthogonal; a first polarizing beam splitter that combines the first laser beam having the first polarization direction and the third laser beam having the second polarization direction; a second wave plate through which the second laser beam or the fourth laser beam passes, and through which, after the second wave plate has passed, the third polarization direction of the second laser beam and the fourth polarization direction of the fourth laser beam are orthogonal; and a second polarizing beam splitter that combines the second laser beam having the third polarization direction and the fourth laser beam having the fourth polarization direction.

17. The light emitting module according to claim 15 or 16, further comprising: a common package accommodating a corresponding first laser light source and a corresponding third laser light source arranged on each of the plurality of mounting surfaces; and another common package accommodating a corresponding second laser light source and a corresponding fourth laser light source arranged on each of the plurality of mounting surfaces.

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