Light emitting device

Abstract

To provide a light emitting device in which the relative positional relationship between a laser beam emitted from a semiconductor laser element and a lens is easily adjusted.SOLUTION: A base member, a semiconductor laser element 20 configured to emit laser light, a light reflecting member 40 configured to reflect the light emitted by the semiconductor laser element upward, and a lens 50 having a flat surface portion located above the light reflecting member and including a region on which the light reflected by the light reflecting member is incident, and a convex surface portion located above the flat surface portion and including a region from which the light incident from the flat surface portion is emitted, when a direction in which the first step portion 131 extends is defined as a first direction, a length of the lens in the first direction is shorter than a length of the lens in a second direction orthogonal to the first direction in a top view, and at least a part of the semiconductor laser element does not overlap with the lens in a top view.SELECTED DRAWING: Figure 2

Description

[Technical Field]

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

[0002] Patent Document 1 discloses a light emitting device including a base having a recess, a submount placed on the bottom surface of the recess, a semiconductor laser element placed on the submount, a light reflecting member placed on the bottom surface of the recess and reflecting light from the semiconductor laser element, a light-transmitting member placed on the top surface of the base, and a lens member placed above the light-transmitting member. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Publication No. 2020-136386 Summary of the Invention [Problem to be solved by the invention]

[0004] An object of the present disclosure is to provide a light emitting device in which the relative positional relationship between the laser light emitted from a semiconductor laser element and a lens can be easily adjusted. [Means for solving the problem]

[0005] A light emitting device according to an embodiment of the present disclosure includes a base body having a main body, a recess provided on an upper surface of the main body, and a step provided inside the recess and extending along an inner side surface of the recess between a bottom surface of the recess and an upper surface of the main body in a height direction; a semiconductor laser element that is disposed between the bottom surface and an upper surface of the step in the height direction and emits laser light; a support portion that is disposed on the bottom surface and supports the semiconductor laser element; a light reflecting member that is disposed on the bottom surface and spaced apart from the support portion and the semiconductor laser element and reflects light emitted by the semiconductor laser element upward; and a lens disposed on an upper surface of the step portion so as to be positioned at a position where the semiconductor laser element overlaps with the upper surface of the step portion and an area overlapping with the light reflecting member in a top view, the lens having: a flat portion including an area where light reflected by the light reflecting member is incident; and a convex portion located above the flat portion and including an area where light incident from the flat portion exits, wherein when the direction in which the step portion extends is defined as a first direction, the length of the lens in the first direction in a top view is shorter than the length of the lens in a second direction perpendicular to the first direction, and at least a portion of the semiconductor laser element does not overlap with the lens in a top view. [Effects of the Invention]

[0006] According to an embodiment of the present disclosure, it is possible to provide a light emitting device in which the relative positional relationship between the laser light emitted from the semiconductor laser element and the lens can be easily adjusted. [Brief explanation of the drawings]

[0007] [Figure 1] FIG. 1 is a top view schematically illustrating a light emitting device according to an embodiment. [Figure 2] FIG. 2 is a top view schematically illustrating the light-emitting device according to the embodiment, in which the light-transmitting member and the folding mirror are omitted. [Figure 3] FIG. 3 is a cross-sectional view schematically showing the light emitting device according to the embodiment taken along line III-III in FIG. [Figure 4]4 is a partially enlarged cross-sectional view schematically illustrating a part of the light emitting device according to the embodiment in a region IV of FIG. 3. FIG. [Figure 5] FIG. 10 is a partially enlarged cross-sectional view schematically showing a part of a light emitting device according to a reference example. [Figure 6] FIG. 10 is a top view schematically showing a light emitting device according to a first modified example of the embodiment. [Figure 7] FIG. 10 is a top view schematically showing another example of the light emitting device 1A according to the first modified example of the embodiment. [Figure 8] FIG. 10 is a perspective view schematically showing a light emitting device according to a second modified example of the embodiment. [Figure 9] FIG. 10 is a top view schematically showing a light emitting device according to a second modified example of the embodiment. [Figure 10] FIG. 10 is a perspective view schematically showing a light emitting device according to a third modified example of the embodiment. [Figure 11] FIG. 10 is a top view schematically showing a light emitting device according to a third modified example of the embodiment. DETAILED DESCRIPTION OF THE INVENTION

[0008] Light-emitting devices according to embodiments of the present disclosure will be described in detail below with reference to the drawings. However, the following embodiments are merely illustrative of light-emitting devices that embody the technical concepts of the embodiments and are not limited thereto. Furthermore, unless otherwise specified, the dimensions, materials, shapes, relative arrangements, etc. of the components described in the embodiments are not intended to limit the scope of the present disclosure, but are merely illustrative examples. Note that the size, positional relationship, etc. of components shown in each drawing may be exaggerated for clarity. Furthermore, in the following description, the same names and symbols indicate the same or similar components, and detailed descriptions will be omitted as appropriate. An end view showing only the cut surface may be used as a cross-sectional view.

[0009] In the figures shown below, directions may be indicated by the X-axis, Y-axis, and Z-axis. The X-axis, Y-axis, and Z-axis are mutually perpendicular. In this specification, the direction along the Y-axis is referred to as the "first direction Y." The direction along the X-axis is referred to as the "second direction X." The direction along the Z-axis is referred to as the "third direction Z." The third direction Z corresponds to the height direction. The direction in which the arrow in the first direction Y points is referred to as the +Y direction or +Y side, and the direction opposite to the +Y direction is referred to as the -Y direction or -Y side. The direction in which the arrow in the second direction X points is referred to as the +X direction or +X side, and the direction opposite to the +X direction is referred to as the -X direction or -X side. The direction in which the arrow in the third direction Z points is referred to as the +Z direction or +Z side, and the direction opposite to the +Z direction is referred to as the -Z direction or -Z side. Furthermore, the +Z direction or +Z side corresponds to "upward," and the -Z direction or -Z side corresponds to "downward." In addition, in the third direction Z, the surface of an object when viewed in the +Z direction or from the +Z side is referred to as the "top surface," and the surface of an object when viewed in the -Z direction or from the -Z side is referred to as the "bottom surface." Furthermore, in this specification, "top view" refers to viewing an object from the +Z direction or from the +Z side. However, these terms are used for convenience of explanation and do not limit the orientation of the light-emitting device when in use. The orientation of the light-emitting device is arbitrary. In the following embodiments, "along the first direction Y, the second direction X, and the third direction Z" includes the object being tilted within a range of ±5° relative to these directions. Furthermore, in the embodiments, "orthogonal" may include an error of ±5° relative to 90°.

[0010] In this disclosure, unless otherwise specified, polygons such as rectangles are referred to as polygons, including shapes in which the corners of the polygon have been processed, such as rounded, chamfered, corner-cut, or rounded. Furthermore, shapes in which processing has been applied not only to the corners (edges of the sides) but also to the middle portions of the sides are also referred to as polygons. In other words, shapes in which partial processing has been applied while retaining the polygon as a base are included in the interpretation of "polygon" described in this disclosure.

[0011] The same applies to terms that describe specific shapes, such as trapezoid, circle, and concave / convex, and terms that relate to the sides that form those shapes. In other words, even if the corners or middle parts of a certain side or circumference are processed, the interpretation of "side" or "circumference" includes the processed parts.

[0012] Furthermore, "cover" or "enclose" is not limited to direct contact, but also includes indirect covering, for example, via another member. Furthermore, "place" is not limited to direct contact, but also includes indirect placement, for example, via another member.

[0013] [Embodiment] An example of the overall configuration of a light emitting device 1 according to an embodiment will be described with reference to Fig. 1 to Fig. 4. Fig. 1 is a top view schematically showing the light emitting device 1 according to an embodiment. Fig. 2 is a top view schematically showing the light emitting device according to an embodiment, with a light-transmitting member 61 and a folding mirror 65 omitted. Fig. 3 is a cross-sectional view schematically showing the light emitting device 1 according to an embodiment, taken along line III-III in Fig. 1. Fig. 4 is a partially enlarged cross-sectional view schematically showing a part of the light emitting device 1 according to an embodiment in region IV in Fig. 3.

[0014] 1 to 4, the light emitting device 1 includes a base 10, a semiconductor laser element 20, a support 30, a light reflecting member 40, and a lens 50. The light emitting device 1 may further include other components such as a light-transmitting member 61, a folding mirror 65, a first terminal 71, a second terminal 72, a third terminal 73, a fourth terminal 74, a first conductor 81, a second conductor 82, a third conductor 83, a fourth conductor 84, a fifth conductor 85, a sixth conductor 86, a seventh conductor 87, and thin conductor wires 91 and 92.

[0015] As will be described separately, the lens 50 is disposed on the upper surface 13a of the step portion 13 of the base 10. The first terminal 71, the second terminal 72, the first conductor 81, the second conductor 82, and the third conductor 83 form a path through which a first current flows for detecting whether the lens 50 is disposed on the upper surface 13a of the step portion 13. Hereinafter, the first terminal 71, the second terminal 72, the first conductor 81, the second conductor 82, and the third conductor 83 may be collectively referred to as "components forming the path of the first current." The fourth conductor 84 and the fifth conductor 85 may also be included in the path through which the first current flows. The third terminal 73, the fourth terminal 74, the sixth conductor 86, and the seventh conductor 87 form a path through which a second current flows for supplying power to the semiconductor laser device 20. Hereinafter, the third terminal 73, the fourth terminal 74, the sixth conductor portion 86, and the seventh conductor portion 87 may be collectively referred to as "members that form the path of the second current."

[0016] <Base 10> An example of the configuration of the base 10 will be described. As shown in FIGS. 1 to 4, the base 10 has a main body 11, a recess 12, and a step 13. As shown in FIGS. 1 and 2, the base 10 may further include other components such as inner layer wirings 15a, 15b, 15c, and 15d provided inside the main body 11. The inner layer wiring 15a may be part of the first terminal 71, or may be provided separately from the first terminal 71. The inner layer wiring 15b may be part of the second terminal 72, or may be provided separately from the second terminal 72. The inner layer wiring 15c may be part of the third terminal 73, or may be provided separately from the third terminal 73. The inner layer wiring 15d may be part of the fourth terminal 74, or may be provided separately from the fourth terminal 74. 1 and 2 show four inner layer wirings 15a, 15b, 15c, and 15d, but the number of inner layer wirings is not limited to this. Furthermore, the positions and sizes of the inner layer wirings 15a, 15b, 15c, and 15d are not limited to those shown in FIGS.

[0017] 1 to 3, the main body 11 has an upper surface 11a, a lower surface 11b, and one or more side surfaces 11c that contact the upper surface 11a and the lower surface 11b. The main body 11 has a substantially rectangular shape when viewed from above. However, the shape of the main body 11 when viewed from above is not limited to a substantially rectangular shape. The shape of the main body 11 when viewed from above may be a shape other than a substantially rectangular shape, such as a substantially circular shape, a substantially elliptical shape, or a substantially polygonal shape other than a rectangle.

[0018] The main body 11 is preferably made of a material such as a ceramic, for example, aluminum nitride, silicon nitride, aluminum oxide, or silicon carbide. However, the main body 11 may be made of a material other than ceramic. For example, the main body 11 may be made of a metal, such as copper.

[0019] The recess 12 is provided on the upper surface 11a of the main body 11. More specifically, as shown in Fig. 3, the recess 12 is recessed from the upper surface 11a of the main body 11 toward the -Z side. When viewed from above, the semiconductor laser element 20, the support 30, the light reflecting member 40, and the lens 50 are arranged inside the recess 12. The recess 12 has a bottom surface 12a as the surface closest to the -Z side.

[0020] The step portion 13 is provided inside the recess 12 and is disposed between the bottom surface 12a of the recess 12 and the upper surface 11a of the main body 11 in the third direction Z. The step portion 13 is disposed extending along the inner surface of the recess 12 (inner surface including inner surfaces 11d1 and 11d2, which will be described separately). In the example shown in FIG. 2 , the step portion 13 extends along the first direction Y. The step portion 13 has an upper surface 13a that is a surface parallel to each of the first direction Y and the second direction X. The step portion 13 has side surfaces that contact the upper surface 13a and the bottom surface 12a of the recess 12. The step portion 13 may be a component that is physically integrated with the main body 11 in the base 10, or may be a component that is physically separate from the main body 11.

[0021] In the example shown in FIG. 2, the step portion 13 has a first step portion 131 and a second step portion 132. The first step portion 131 and the second step portion 132 are arranged to be spaced apart in the second direction X so as to sandwich the semiconductor laser element 20 in a top view. As shown in FIG. 2, the first step portion 131 protrudes toward the +X side from an inner surface 11d1 of the main body 11 that defines the recess 12. The second step portion 132 protrudes toward the -X side from an inner surface 11d2 of the main body 11 that defines the recess 12. Of the upper surfaces 13a of the step portion 13, the upper surface of the first step portion 131 will be referred to as the "upper surface 131a" below. Furthermore, of the upper surfaces 13a of the step portion 13, the upper surface of the second step portion 132 will be referred to as the "upper surface 132a" below.

[0022] <Semiconductor laser element 20> Next, a configuration example of the semiconductor laser element 20 will be described. As shown in Fig. 3, the semiconductor laser element 20 is disposed between the bottom surface 12a of the recess 12 and the upper surface 13a of the step portion 13 in the third direction Z. As shown in Fig. 4, the semiconductor laser element 20 is preferably bonded to the support portion 30 via a conductive bonding portion 35. By being bonded via the conductive bonding portion 35, it is possible to supply current to the semiconductor laser element 20 via the bonding portion 35.

[0023] 4, the semiconductor laser element 20 has a semiconductor structure 21, a first electrode 22, and a second electrode 23. In the example shown in Fig. 4, the second electrode 23, the semiconductor structure 21, and the first electrode 22 are stacked in this order in the third direction Z. However, the positional relationship between the semiconductor structure 21, the first electrode 22, and the second electrode 23 is not limited to this.

[0024] The semiconductor structure 21 has an upper surface, a lower surface, and one or more side surfaces in contact with the upper and lower surfaces. The semiconductor structure 21 emits light toward the +Y side. When the semiconductor structure 21 is rectangular, the light emitted by the semiconductor structure 21 is emitted from one of the one or more side surfaces of the semiconductor structure 21 that is located on the +Y side. Hereinafter, the side surface on the +Y side of the semiconductor structure 21 will be referred to as the "light emitting end surface 20S" of the semiconductor laser element 20.

[0025] The semiconductor laser element 20 emits laser light. The light (laser light) emitted from the semiconductor laser element 20 has a divergence and forms an elliptical far-field pattern (hereinafter referred to as "FFP") on a plane parallel to the light-emitting end face 20S. Here, FFP refers to the shape and light intensity distribution of light at a position away from the light-emitting end face 20S. The optical path of light traveling through the center of the elliptical shape of the FFP is referred to as the "optical axis 20OA" of that light, and light passing through the center of the elliptical shape of the FFP, in other words, light with peak intensity in the light intensity distribution of the FFP, is referred to as "light traveling along the optical axis 20OA" or "light passing through the optical axis 20OA."

[0026] The semiconductor structure 21 includes a first semiconductor layer, an active layer, and a second semiconductor layer. The first semiconductor layer is disposed on the +Z side of the semiconductor structure 21. An upper surface of the first semiconductor layer defines an upper surface of the semiconductor structure 21. The second semiconductor layer is disposed on the -Z side of the semiconductor structure 21. A lower surface of the second semiconductor layer defines a lower surface of the semiconductor structure 21. The active layer is disposed between the first semiconductor layer and the second semiconductor layer in the third direction Z.

[0027] One of the first semiconductor layer and the second semiconductor layer is an n-type semiconductor layer. The other of the first semiconductor layer and the second semiconductor layer is a p-type semiconductor layer. The active layer may have a single quantum well (SQW) structure or a multiple quantum well (MQW) structure including multiple well layers. Each of the first semiconductor layer, the active layer, and the second semiconductor layer in the semiconductor structure 21 is made of, for example, In. X Al Y Ga 1-X-Y The first semiconductor layer, the active layer, and the second semiconductor layer are made of nitride-based semiconductors such as N (0≦X, 0≦Y, X+Y≦1). However, the materials constituting the first semiconductor layer, the active layer, and the second semiconductor layer are not limited to nitride-based semiconductors.

[0028] The first electrode 22 is disposed on the upper surface of the semiconductor structure 21. The first electrode 22 is electrically connected to the first semiconductor layer. If the first semiconductor layer is an n-type semiconductor layer, the first electrode 22 corresponds to an n-side electrode. If the first semiconductor layer is a p-type semiconductor layer, the first electrode 22 corresponds to a p-side electrode. The first electrode 22 is also electrically connected to a thin conductor wire 91 such as a bonding wire. The thin conductor wire 91 electrically connects the sixth conductor portion 86 on the upper surface 131a of the first step portion 131 to the first electrode 22.

[0029] Examples of materials that can be used to form the first electrode 22 include single metal materials such as gold, silver, aluminum, nickel, rhodium, copper, titanium, platinum, palladium, molybdenum, chromium, and tungsten, as well as alloy materials containing these metals. However, the materials that can be used to form the first electrode 22 are not limited to these. The first electrode 22 can have a single-layer structure made of a single metal material or alloy material, or a layered structure in which multiple metal materials or alloy materials are layered along the third direction Z.

[0030] The second electrode 23 is disposed on the lower surface of the semiconductor structure 21. The second electrode 23 is electrically connected to the second semiconductor layer. If the second semiconductor layer is a p-type semiconductor layer, the second electrode 23 corresponds to a p-side electrode. If the second semiconductor layer is an n-type semiconductor layer, the second electrode 23 corresponds to an n-side electrode. As shown in FIG. 4 , the lower surface of the second electrode 23 is bonded to the upper surface of the bonding portion 35. The second electrode 23 is electrically connected to a thin conductor wire 92, such as a bonding wire, via the bonding portion 35. The thin conductor wire 92 electrically connects the seventh conductor portion 87 on the upper surface 132a of the second step portion 132 to the upper surface of the bonding portion 35. The bonding portion 35 includes a region to which the semiconductor laser element 20 is physically bonded and a region to which the thin conductor wire 92 is physically bonded. In the bonding portion 35, the region where the semiconductor laser element 20 is physically bonded and the region where the thin conductor wires 92 are physically bonded may be integrally formed or may be separate. When the region where the semiconductor laser element 20 is physically bonded and the region where the thin conductor wires 92 are physically bonded are separate, these regions may be electrically connected via the inside of the support portion 30.

[0031] The second electrode 23 may be made of the same metal material or alloy material as the first electrode 22. Similarly to the first electrode 22, the second electrode 23 may have a single-layer structure made of a single metal material or alloy material, or may have a layered structure in which a plurality of metal materials or alloy materials are layered along the third direction Z.

[0032] <Support part 30> Next, a configuration example of the support part 30 will be described. The support part 30 is disposed on the bottom surface 12a of the recess 12 to support the semiconductor laser element 20. As shown in FIGS. 1 to 4, the support part 30 has an upper surface, a lower surface, and one or more side surfaces that contact the upper and lower surfaces. As shown in FIGS. 3 and 4, the upper surface of the support part 30 is bonded to, for example, the lower surface of the bonding part 35. Furthermore, the lower surface of the support part 30 is bonded to the bottom surface 12a of the recess 12.

[0033] The support 30 is, for example, a submount. However, the support 30 is not limited to a submount. For example, the support 30 may be a protruding portion in which a part of the bottom surface 12a of the recess 12 protrudes toward the +Z side. In this case, the semiconductor laser element 20 is placed on the protruding portion of the bottom surface 12a corresponding to the support 30, for example, via a bonding portion 35.

[0034] In the following, the supporting part 30 will be described as a submount. As shown in FIG. 4, the +Y-side side surface 31S of the supporting part 30 is preferably located closer to the -Y side than the light-emitting end surface 20S of the semiconductor laser element 20. That is, the light-emitting end surface 20S of the semiconductor laser element 20 is located protruding from the +Y-side side surface 31S of the supporting part 30 in a top view. By having the light-emitting end surface 20S of the semiconductor laser element 20 protruding from the +Y-side side surface 31S of the supporting part 30, it is possible to prevent the supporting part 30 from overlapping with the irradiation range of light emitted from the light-emitting end surface 20S. As a result, it is possible to prevent the light emitted by the semiconductor laser element 20 from being reflected by the supporting part 30, thereby preventing a decrease in light intensity in a desired irradiation range and a disturbance in the light distribution pattern.

[0035] Examples of materials that can be used to form the support 30 include materials with excellent heat dissipation properties, such as ceramics such as silicon nitride, aluminum nitride, and silicon carbide, and metals such as copper. By forming the support 30 from these materials, heat generated in the semiconductor laser element 20 performing light emission operation can be efficiently conducted to the main body 11 of the base 10, etc. This reduces the impact on the light emission efficiency of the semiconductor laser element 20 caused by an excessive increase in the temperatures of the semiconductor laser element 20 and the support 30. However, the materials that can be used to form the support 30 are not limited to these.

[0036] <Light reflecting member 40> Next, a configuration example of the light reflecting member 40 will be described. The light reflecting member 40 reflects the light emitted by the semiconductor laser element 20 to the +Z side. As shown in Figures 2 to 4, the light reflecting member 40 is disposed on the bottom surface 12a of the recess 12, spaced apart from the semiconductor laser element 20 and the support part 30.

[0037] The light-reflecting member 40 has a light-reflecting surface 41, a bottom surface, and one or more side surfaces in contact with the light-reflecting surface 41 and the bottom surface. The light-reflecting member 40 may have a top surface in contact with the light-reflecting surface 41 and one or more side surfaces. The light-reflecting surface 41 faces the light-emitting end surface 20S of the semiconductor laser device 20. In the examples shown in FIGS. 3 and 4, the light-reflecting surface 41 is an inclined surface, but it may also be a curved surface such as a convex or concave surface. The light-reflecting surface 41 may be made of quartz, glass such as BK7 (borosilicate glass), metal such as aluminum or silver, silicon, a dielectric multilayer film, or the like.

[0038] The upper end of the light reflecting member 40 is preferably located on the -Z side of the upper surface 13a of the step portion 13. More specifically, the upper end of the light reflecting surface 41 and the upper surface of the light reflecting member 40 are located on the -Z side of the upper surface 13a of the step portion 13. By having the upper end of the light reflecting member 40 located on the -Z side of the upper surface 13a of the step portion 13, it is possible to reduce the possibility that the lens 50 will come into contact with the light reflecting member 40 when the lens 50 is placed on the +Z side of the light reflecting member 40 and on the upper surface 13a of the step portion 13.

[0039] 2, the light reflecting member 40 has an area that overlaps with the lens 50 in top view and an area that does not overlap with the lens 50. By having the light reflecting member 40 have an area that does not overlap with the lens 50 in top view, it can be easily confirmed that the light reflecting member 40 is appropriately positioned in a desired position in the design. Note that the light reflecting member 40 does not have to have an area that does not overlap with the lens 50 in top view.

[0040] <Lens 50> Next, a configuration example of the lens 50 will be described. The lens 50 is disposed on the upper surface 13a of the step portion 13 so as to be located on the +Z side of the light reflecting member 40. In the example shown in FIG. 2, the lens 50 is supported by the upper surface 131a of the first step portion 131 and the upper surface 132a of the second step portion 132. In a top view, the length of the lens 50 in the first direction Y is shorter than the length of the lens 50 in the second direction X. Note that the length of the lens 50 in the first direction Y refers to the distance in the first direction Y between the point of the lens 50 closest to the -Y side and the point of the lens 50 closest to the +Y side in a top view. Furthermore, the length of the lens 50 in the second direction X refers to the distance in the second direction X between the point of the lens 50 closest to the -X side and the point of the lens 50 closest to the +X side in a top view.

[0041] The lens 50 has a flat portion 51 and a convex portion 52. The lens 50 may further have lens side surfaces 53 and 54 that contact the flat portion 51 and the convex portion 52. The lens side surfaces 53 and 54 each extend parallel to the third direction Z. The lens side surfaces 53 and 54 are, for example, spaced apart in the first direction Y and arranged facing each other. The lens side surface 53 connects the outer edges of the flat portion 51 and the convex portion 52 on the +Y side. The lens side surface 54 connects the outer edges of the flat portion 51 and the convex portion 52 on the -Y side. The lens 50 is, for example, a cylindrical lens. Because the lens 50 is a cylindrical lens, the shape of the convex portion 52 of the lens 50 is the same at any position in the second direction X. That is, the lens 50 can act on light incident on the lens 50 in the same way regardless of the position in the second direction X.

[0042] For example, the lens 50 reduces the divergence angle of the component in the first direction Y of the laser light incident on the flat surface 51 of the lens 50 more than the divergence angle of the component in the second direction X. Furthermore, for example, the lens 50 collimates the component in the first direction Y of the laser light incident on the flat surface 51 of the lens 50, but does not collimate the component in the second direction X. This configuration provides a lens that collimates only the laser light incident on the flat surface 51 of the lens 50 in a necessary direction. This configuration also allows the size of the lens 50 to be reduced for directions that do not require collimation, thereby reducing the size of the light emitting device 1. In the present disclosure, the component in the first direction Y of the laser light incident on the flat surface 51 of the lens 50 is the fast axis component, and the component in the second direction X is the slow axis component. Therefore, in the present disclosure, the lens 50 functions as a FAC (Fast-Axis Collimating) lens.

[0043] The flat surface portion 51 is disposed on the -Z side of the lens 50. The flat surface portion 51 is a surface that extends parallel to both the first direction Y and the second direction X. The flat surface portion 51 has a strip shape that is long in the second direction X in a top view. That is, the longitudinal direction of the flat surface portion 51 is parallel to the second direction X, and the lateral direction of the flat surface portion 51 is parallel to the first direction Y.

[0044] The flat portion 51 includes an area overlapping the upper surface 13a of the step portion 13 in a top view. More specifically, the flat portion 51 includes an area overlapping the upper surface 131a of the first step portion 131 and an area overlapping the upper surface 132a of the second step portion 132 in a top view. In the example shown in FIG. 2 , the −X side end of the flat portion 51 overlaps the upper surface 131a of the first step portion 131 in a top view. That is, the −X side end of the flat portion 51 is supported by the upper surface 131a of the first step portion 131. Furthermore, the +X side end of the flat portion 51 overlaps the upper surface 132a of the second step portion 132. That is, the +X side end of the flat portion 51 is supported by the upper surface 132a of the second step portion 132. This allows the lens 50 to be stably supported at a position on the +Z side of the light reflecting member 40.

[0045] The flat portion 51 further includes an area onto which light emitted by the semiconductor laser element 20 and reflected by the light reflecting member 40 is incident. The area of ​​the flat portion 51 onto which the light reflected by the light reflecting member 40 is incident is located between an area overlapping with the upper surface 131a of the first step portion 131 and an area overlapping with the upper surface 132a of the second step portion 132 in a top view. The flat portion 51 corresponds to the light incident surface of the lens 50.

[0046] The convex surface portion 52 is disposed on the +Z side of the lens 50. The convex surface portion 52 is located above the flat surface portion 51. Furthermore, the convex surface portion 52 overlaps with the flat surface portion 51 in a top view. Light that enters the lens 50 from the flat surface portion 51 reaches the convex surface portion 52. The convex surface portion 52 includes an area from which light that enters the interior of the lens 50 from the flat surface portion 51 exits. In other words, the convex surface portion 52 corresponds to the light exit surface of the lens 50.

[0047] When the convex surface portion 52 is viewed from the side of the lens 50, i.e., from the second direction X, it is preferable that the curvature of the convex surface portion 52 is substantially constant regardless of the position of the convex surface portion 52 in the second direction X. As shown in Figures 3 and 4, the convex surface portion 52 has a spherical shape when viewed from the second direction X. However, the convex surface portion 52 may have an aspherical shape when viewed from the second direction X.

[0048] 3, the top of the convex portion 52 is preferably located on the -Z side of the upper surface 11a of the main body 11 of the base 10. By having the top of the convex portion 52 located on the -Z side of the upper surface 11a of the main body 11, an increase in the length of the light emitting device 1 in the third direction Z is suppressed, and an increase in the size of the light emitting device 1 can be suppressed. Furthermore, by having the top of the convex portion 52 located on the -Z side of the upper surface 11a of the main body 11, even if the light-transmitting member 61 is arranged to overlap the recessed portion 12 of the base 10 in a top view, the convex portion 52 and the light-transmitting member 61 do not come into contact with each other. In other words, the convex portion 52 does not prevent the light-transmitting member 61 from covering the recessed portion 12 from the +Z side.

[0049] The convex surface portion 52 collimates the light that has reached the convex surface portion 52 and emits it to the +Z side. Here, in this specification, "collimate" includes not only deflecting light to make it parallel, but also reducing the spread angle of light.

[0050] In top view, a straight line passing through the center of gravity of the lens 50 and parallel to the second direction X is defined as the center line 50M. In FIG. 2, in top view, the center line 50M of the lens 50 and the optical axis 20OA of the semiconductor laser element 20 are orthogonal to each other. As a result, the optical effect of the lens 50 on the light emitted from the semiconductor laser element 20 is constant regardless of the position of the lens 50 in the second direction X, facilitating optical design using the light emitting device 1. If the lens 50 is a prism-shaped body such as a cylindrical lens, the center line 50M is, for example, the generatrix of the lens 50.

[0051] As shown in FIG. 2, the center line 50M of the lens 50 is perpendicular to the first direction Y in top view. That is, the center line 50M of the lens 50 is parallel to the second direction X in top view. Furthermore, in the lens 50, the direction perpendicular to the center line 50M is parallel to the first direction Y. Hereinafter, the length of the lens 50 in the direction perpendicular to the center line 50M will be referred to as the "length L1 of the lens 50 in the first direction Y" (see FIG. 4).

[0052] In a top view, the length L1 of the lens 50 in the first direction Y is at least twice the length L2 in the third direction Z from the bottom surface 12a of the recess 12 to the optical axis 20OA of the light emitted from the semiconductor laser element 20. In the example shown in Fig. 4, the length L1 of the lens 50 in the first direction Y is at least twice the length in the third direction Z from the bottom surface 12a of the recess 12 to the lower surface of the second electrode 23 of the semiconductor laser element 20.

[0053] A reference example, which is different from the present disclosure and in which a lens 50 is provided so that the flat portion 51 and the light-emitting end surface 20S of the semiconductor laser element 20 are parallel, will be described with reference to FIG. 5 . FIG. 5 is a partially enlarged cross-sectional view schematically illustrating a part of a light-emitting device according to the reference example. In the reference example illustrated in FIG. 5 , the lens 50 is disposed between the light-emitting end surface 20S of the semiconductor laser element 20 and the light-reflecting surface 41 of the light-reflecting member 40 so that the flat portion 51 and the light-emitting end surface 20S face each other. In this case, the length of the lens 50 in a direction (third direction Z) perpendicular to both the center line 50M and the optical axis of the light emitted by the semiconductor laser element 20 is referred to as the “length L3 of the lens 50 in the third direction Z.” When the lens 50 is provided so that the flat portion 51 and the light-emitting end surface 20S of the semiconductor laser element 20 are parallel, the length L3 of the lens 50 in the third direction Z corresponds to the length from the end of the flat portion 51 on the +Z side to the end on the −Z side. 5, the length L3 of the lens 50 in the third direction Z may be rephrased as the distance between the lens side surface 53 and the lens side surface 54 when viewed from the second direction X. The distance in the third direction Z between the center line 50M of the lens 50 that is farthest from the flat portion 51 (the center line 50M passing through the black dots shown in FIG. 5; this center line 50M will be simply referred to as the "center line 50M"), i.e., the center line 50M that overlaps with the apex of the convex portion 52, and the lens side surface 53 or the lens side surface 54 is 0.5 times the length L3 of the lens 50 in the third direction Z (the length of "L4" shown in FIG. 5). The lens 50 is preferably provided so that the optical axis 20OA of the light emitted from the semiconductor laser element 20 is perpendicular to the center line 50M of the lens 50. When providing lens 50 in this manner, the lens side surface closer to bottom surface 12a of recess 12 needs to be positioned higher (on the +Z side) than bottom surface 12a to avoid contact between lens side surface 53 and lens side surface 54 that is closer to bottom surface 12a of recess 12 and bottom surface 12a of recess 12. Therefore, length L4, which is 0.5 times length L3 of lens 50 in third direction Z and corresponds to the distance between center line 50M of lens 50 and lens side surface 53 or lens side surface 54, cannot be made larger than length L2 from bottom surface 12a of recess 12 to optical axis 20OA of light emitted from semiconductor laser element 20 in third direction Z.That is, in order to make the length L3 of the lens 50 in the third direction Z at least twice the length L2 in the third direction Z from the bottom surface 12a of the recess 12 to the optical axis 20OA of the light emitted from the semiconductor laser element 20, it is necessary to take measures such as increasing the thickness of the support part 30 in the third direction Z to increase the length L2 in the third direction Z from the bottom surface 12a of the recess 12 to the optical axis 20OA of the light emitted from the semiconductor laser element 20. However, such measures result in an increase in the size of the light emitting device 1.

[0054] In contrast, in the present disclosure, the lens 50 is not disposed between the light-emitting end surface 20S of the semiconductor laser element 20 and the light-reflecting surface 41 of the light-reflecting member 40, but is disposed on the upper surface 13a of the step portion 13. This allows the lens 50 to be disposed at a position on the +Z side of the light-reflecting member 40, without increasing the length L2 from the bottom surface 12a of the recess 12 to the optical axis 20OA of the light emitted from the semiconductor laser element 20 in the third direction Z. The length L1 of the lens 50 in the first direction Y is at least twice the length L2 from the bottom surface 12a of the recess 12 to the optical axis 20OA of the light emitted from the semiconductor laser element 20 in the third direction Z. In other words, a relatively large lens 50 can be used without increasing the length (thickness) of the support portion 30 in the third direction Z. As a result, compared to the reference example in which the lens 50 is disposed so that the flat portion 51 and the light-emitting end surface 20S of the semiconductor laser element 20 are parallel to each other, the optical path of the light reflected by the light-reflecting member 40 can be adjusted using a relatively large lens 50. By disposing a relatively large lens 50, it is possible to increase the area where the lens 50 and the light reflecting member 40 overlap in a top view. As a result, it is possible to reduce the possibility that some of the light reflected by the light reflecting member 40 will not pass through the lens 50 and be uncollimated. Furthermore, by not increasing the length (thickness) of the support portion 30 in the third direction Z, it is possible to reduce deterioration in the heat dissipation performance of the semiconductor laser element 20 caused by the support portion 30. In other words, by disposing the lens 50 on the upper surface 13a of the step portion 13, it is possible to use a relatively large lens 50 without deteriorating the heat dissipation performance of the semiconductor laser element 20.

[0055] In the present disclosure, at least a portion of the semiconductor laser element 20 does not overlap with the lens 50 in a top view. With this configuration, even if the lens 50 is provided, the semiconductor laser element 20 can be confirmed in a top view. Therefore, even if a relatively large lens 50 is provided, the mounting position of the semiconductor laser element 20, etc., can be confirmed. This configuration also makes it easy to provide the thin conductor wires 91 on the top surface of the semiconductor laser element 20. Furthermore, in the present disclosure, the length of the lens 50 in the first direction Y is shorter than the length of the lens 50 in the second direction X. This configuration makes it easy to move the lens 50 in the first direction Y on the step portion 13, and to adjust the relative positional relationship between the laser light emitted from the semiconductor laser element 20 and the lens 50. In the example shown in FIG. 2, the length of the step portion 13 in the first direction Y (at least one of the length of the first step portion 131 in the first direction Y and the length of the second step portion 132 in the first direction Y in FIG. 2) is at least twice the length of the lens 50 in the first direction Y. Since the length of the step portion 13 in the first direction Y is more than twice the length of the lens 50 in the first direction Y, the position of the lens 50 relative to the optical axis 20OA can be freely adjusted within the range in which the optical axis 20OA of the light emitted by the semiconductor laser element 20 reflected by the light reflecting member 40 is incident on the flat portion 51 of the lens 50.

[0056] 2, the lens 50 is disposed so as to straddle the first step portion 131 and the second step portion 132. This allows the lens 50 to be stably disposed while ensuring a range of movement of the lens 50 in the first direction Y.

[0057] Furthermore, in a top view, the length L1 of the lens 50 in the first direction Y is preferably four times or less the length L2 in the third direction Z from the bottom surface 12a of the recess 12 to the optical axis 20OA of the light emitted from the semiconductor laser element 20. By setting the length L1 of the lens 50 in the first direction Y to four times or less the length L2 in the third direction Z from the bottom surface 12a of the recess 12 to the optical axis 20OA of the light emitted from the semiconductor laser element 20, it is possible to prevent the light emitting device 1 from becoming large.

[0058] <Translucent member 61> Next, a configuration example of the light-transmitting member 61 will be described. The light-transmitting member 61 overlaps with the recess 12 of the base 10 in a top view. That is, the light-transmitting member 61 covers the recess 12 from the +Z side. As a result, the semiconductor laser element 20, the light reflecting member 40, and the lens 50 are each housed in a space defined by the base 10 and the light-transmitting member 61. In other words, the semiconductor laser element 20, the light reflecting member 40, and the lens 50 are hermetically sealed by the base 10 and the light-transmitting member 61. This makes it possible to reduce particulate matter such as dust and / or dirt floating outside from entering the recess 12 and adhering to each of the components such as the semiconductor laser element 20, the light reflecting member 40, and the lens 50. That is, by hermetically sealing the semiconductor laser element 20, the light reflecting member 40, and the lens 50 with the base 10 and the light-transmitting member 61, it is possible to reduce contamination of each member such as the semiconductor laser element 20, the light reflecting member 40, and the lens 50. As a result, it is possible to improve the reliability of the light emitting device 1.

[0059] As shown in Fig. 3, the light-transmitting member 61 is disposed on the +Z side of the lens 50. The light-transmitting member 61 is translucent to light emitted from the convex surface portion 52 of the lens 50. Here, in this specification, "light-transmitting" means that the light transmittance is 60% or more, preferably 80% or more. Examples of materials that can form the light-transmitting member 61 include insulating materials such as sapphire, spinel, and glass, and semiconductor materials such as aluminum nitride and silicon carbide. However, the material that can form the light-transmitting member 61 is not limited to these.

[0060] The light emitted from the convex surface 52 of the lens 50 and transmitted through the light-transmitting member 61 travels toward the folding mirror 65 .

[0061] <Folding mirror 65> Next, a configuration example of the folding mirror 65 will be described. The folding mirror 65 is an optical member that reflects light that has been emitted from the convex surface 52 of the lens 50 and transmitted through the light-transmitting member 61 in a predetermined direction. In the example shown in FIG. 3, the folding mirror 65 is disposed on the light-transmitting member 61. Also, in the example shown in FIG. 3, the folding mirror 65 reflects light that has been emitted from the convex surface 52 of the lens 50 and transmitted through the light-transmitting member 61 to the +Y side. However, the position of the folding mirror 65 and the light reflection direction are not limited to these. It is also possible to extract the light that has been transmitted through the light-transmitting member 61 as it is, without providing the folding mirror 65.

[0062] <Components that form the path of the first current> Next, an example of a component that forms a path of a first current for detecting whether the lens 50 is disposed on the step portion 13 will be described. Examples of components that form the path of the first current include the first terminal 71, the second terminal 72, the first conductor 81, the second conductor 82, and the third conductor 83. In this embodiment, the components that form the path of the first current further include a fourth conductor 84 and a fifth conductor 85. Each of the first terminal 71, the second terminal 72, the first conductor 81, the second conductor 82, the third conductor 83, the fourth conductor 84, and the fifth conductor 85 may be made of a single metal material such as gold, silver, aluminum, nickel, rhodium, copper, titanium, platinum, palladium, molybdenum, chromium, or tungsten, or an alloy material containing these metals.

[0063] The first terminal 71 is electrically connected to an external detection circuit. An example of the external detection circuit is an electronic circuit such as a microcomputer including a processor such as a CPU (Central Processing Unit) and a storage medium such as a memory. As shown in FIGS. 1 and 2, the first terminal 71 is provided on the main body 11 of the base 10. In the example shown in FIGS. 1 and 2, the first terminal 71 is a rod-shaped metal member provided on the side surface 11c on the -X side of the main body 11. The first terminal 71 extends into the main body 11 and reaches the inner layer wiring 15a. However, the position, size, shape, and other configurations of the first terminal 71 are not limited thereto.

[0064] The first conductor portion 81 is electrically connected to, for example, the inner layer wiring 15a. That is, the first conductor portion 81 is electrically connected to the first terminal 71 via the inner layer wiring 15a. As shown in FIGS. 2 to 4 , the first conductor portion 81 is disposed on the upper surface 131a of the first step portion 131. A portion of the first conductor portion 81 (a portion on the -Y side) overlaps with the flat portion 51 of the lens 50 in top view. In the example shown in FIG. 2 , a portion of the first conductor portion 81 overlaps with the end of the flat portion 51 on the -X side in top view. However, the first conductor portion 81 does not have to extend to a position where it overlaps with the flat portion 51 of the lens 50 in top view. For example, the first conductor portion 81 may extend to a position where it contacts the second conductor portion 82 and terminate at the position where it contacts the second conductor portion 82. It is sufficient that the first conductor portion 81 is electrically connected to the second conductor portion 82.

[0065] 2 to 4, the second conductor portion 82 is disposed on the lens side surface 53. However, the second conductor portion 82 may also be disposed on the lens side surface 54. The second conductor portion 82 extends parallel to the center line 50M of the lens 50 in a top view. The second conductor portion 82 is electrically connected to each of the first conductor portion 81 and the third conductor portion 83. More specifically, as shown in FIG. 2, the second conductor portion 82 extends to the end of the lens side surface 53 on the -X side and is joined to the first conductor portion 81. The second conductor portion 82 extends to the end of the lens side surface 53 on the +X side and is joined to the third conductor portion 83.

[0066] The second conductor 82 is not disposed on the flat surface portion 51 or the convex surface portion 52 of the lens 50. This allows the second conductor 82 to be disposed without blocking the optical path of light that reaches the lens 50 from the light reflecting member 40 and light that passes through the lens 50 and travels toward the light-transmitting member 61.

[0067] The third conductor portion 83 is electrically connected to the second conductor portion 82. As shown in FIG. 2, the third conductor portion 83 is disposed on the upper surface 132a of the second step portion 132. A portion of the third conductor portion 83 (a portion on the -Y side) overlaps with the flat portion 51 of the lens 50 in a top view. In the example shown in FIG. 2, a portion of the third conductor portion 83 overlaps with the +X side of the flat portion 51. However, the third conductor portion 83 does not have to extend to a position where it overlaps with the flat portion 51 of the lens 50 in a top view. For example, the third conductor portion 83 may extend to a position where it contacts the second conductor portion 82 and terminate at the position where it contacts the second conductor portion 82. The third conductor portion 83 is only required to be electrically connected to the second conductor portion 82. The third conductor portion 83 is also electrically connected to the inner layer wiring 15b provided in the main body 11 of the base 10.

[0068] The fourth conductor 84 is provided on the flat portion 51 of the lens 50. The fourth conductor 84 is disposed between the upper surface 131a of the first step portion 131 and the flat portion 51. The fourth conductor 84 is electrically connected to the first conductor 81, the second conductor 82, and the third conductor 83. The fourth conductor 84 is in contact with the second conductor 82. The fourth conductor 84 may be disposed on the first conductor 81. Disposing the fourth conductor 84 between the upper surface 131a of the first step portion 131 and the flat portion 51 can improve adhesion between the lens 50 and the first conductor 81. When the first conductor 81 does not extend to a position overlapping with the flat portion 51 in a top view, disposing the fourth conductor 84 between the upper surface 131a of the first step portion 131 and the flat portion 51 can improve adhesion between the lens 50 and the upper surface 131a of the first step portion 131.

[0069] The fifth conductor 85 is provided on the flat portion 51 of the lens 50. The fifth conductor 85 is disposed between the upper surface 132a of the second step portion 132 and the flat portion 51. The fifth conductor 85 is electrically connected to the first conductor 81, the second conductor 82, and the third conductor 83. The fifth conductor 85 is in contact with the second conductor 82. The fifth conductor 85 may be disposed on the third conductor 83. Disposing the fifth conductor 85 between the upper surface 132a of the second step portion 132 and the flat portion 51 can improve adhesion between the lens 50 and the third conductor 83. When the third conductor 83 does not extend to a position overlapping with the flat portion 51 in a top view, disposing the fifth conductor 85 between the upper surface 132a of the second step portion 132 and the flat portion 51 can improve adhesion between the lens 50 and the upper surface 132a of the second step portion 132.

[0070] The second terminal 72 is electrically connected to an external first power supply, which is not shown in Figures 1 and 2.

[0071] The second terminal 72 is provided on the main body 11 of the base 10. In the example shown in FIGS. 1 and 2, the second terminal 72 is a rod-shaped metal member provided on the side surface 11c on the +X side of the main body 11. The second terminal 72 extends inside the main body 11 and reaches the inner layer wiring 15b. That is, the second terminal 72 is electrically connected to the third conductor portion 83 via the inner layer wiring 15b. However, the position, size, shape, and other configurations of the second terminal 72 are not limited to this.

[0072] When the lens 50 is disposed on the step portion 13, i.e., when the lens 50 is supported by the upper surface 131a of the first step portion 131 and the upper surface 132a of the second step portion 132 and is positioned on the +Z side of the light reflecting member 40, the first terminal 71, the first conductor portion 81, the second conductor portion 82, the third conductor portion 83, and the second terminal 72 are electrically connected to each other. Therefore, a first current from the first power supply flows to an external detection circuit through the second terminal 72, the third conductor portion 83, the second conductor portion 82, the first conductor portion 81, and the first terminal 71. As a result, the external detection circuit detects that the lens 50 is disposed on the step portion 13. Note that the direction of the first current is not limited to this.

[0073] On the other hand, when the lens 50 is separated from the step portion 13, that is, when the lens 50 is separated from at least one of the upper surface 131a of the first step portion 131 and the upper surface 132a of the second step portion 132, the path of the first current does not reach the first conductor portion 81 and is interrupted midway. Therefore, the first current from the first power supply does not reach the external detection circuit. This allows the external detection circuit to detect that the lens 50 is separated from the step portion 13. As a result, it is possible to quickly detect that the lens 50 is not located on the +Z side of the light reflecting member 40.

[0074] 2, the lens 50 is supported on both the upper surface 131a of the first step portion 131 and the upper surface 132a of the second step portion 132, so that a path for a first current from the first power source to an external detection circuit can be easily established using the placement area of ​​the lens 50. Furthermore, simply by passing the first current from the first power source to the external detection circuit, it is possible to detect that the lens 50 is placed on the step portion 13. In other words, the circuit configuration for detecting that the lens 50 is placed on the step portion 13 can be simplified.

[0075] Furthermore, a portion of the first conductor 81 overlapping the planar portion 51 in a top view, the second conductor 82, and a portion of the third conductor 83 overlapping the planar portion 51 in a top view are each arranged in a region of the planar portion 51 of the lens 50 excluding the region onto which light reflected by the light reflecting member 40 is incident. Similarly, the fourth conductor 84 and the fifth conductor 85 are also arranged in a region of the planar portion 51 of the lens 50 excluding the region onto which light reflected by the light reflecting member 40 is incident. Therefore, light reaching the lens 50 from the light reflecting member 40 is not blocked by components that form the path of the first current, such as the first conductor 81, the second conductor 82, the third conductor 83, the fourth conductor 84, and the fifth conductor 85. Furthermore, the first conductor 81, the second conductor 82, the third conductor 83, the fourth conductor 84, and the fifth conductor 85 are not arranged on the convex portion 52 of the lens 50. Therefore, the light that passes through the lens 50 and is emitted from the convex portion 52 is not blocked by components that form the path of the first current, such as the first conductor portion 81, the second conductor portion 82, the third conductor portion 83, the fourth conductor portion 84, and the fifth conductor portion 85.

[0076] 2, the first current is supplied from the second terminal 72, passes through each component that forms the path of the first current, and flows to the first terminal 71. However, the direction of the first current is not limited to this. For example, the first current may be supplied from the first terminal 71, passes through each component that forms the path of the first current, and flows to the second terminal 72. That is, the first terminal 71 may be electrically connected to the first power supply, and the second terminal 72 may be electrically connected to an external detection circuit.

[0077] <Components arranged in the path of the second current> Next, a description will be given of examples of members that serve as a path through which the second current flows for supplying power to the semiconductor laser device 20. Examples of members that serve as the path of the second current include the third terminal 73, the fourth terminal 74, the sixth conductor 86, and the seventh conductor 87. Each of the third terminal 73, the fourth terminal 74, the sixth conductor 86, and the seventh conductor 87 may be made of a single metal material such as gold, silver, aluminum, nickel, rhodium, copper, titanium, platinum, palladium, molybdenum, chromium, tungsten, or an alloy material containing these metals.

[0078] The third terminal 73 is electrically connected to an external second power source. The second power source is not shown in FIGS. 1 and 2. As shown in FIGS. 1 and 2, the third terminal 73 is provided on the main body 11 of the base 10. In the example shown in FIGS. 1 and 2, the third terminal 73 is a rod-shaped metal member provided on the side surface 11c on the -Y side of the main body 11. The third terminal 73 extends into the main body 11 and reaches the inner layer wiring 15c. However, the position, size, shape, and other configurations of the third terminal 73 are not limited to this.

[0079] The sixth conductor portion 86 is disposed on the upper surface 131a of the first step portion 131. The sixth conductor portion 86 is electrically connected to the third terminal 73 via, for example, an inner layer wiring 15c. The sixth conductor portion 86 is also electrically connected to the first electrode 22 of the semiconductor laser device 20 via a thin conductor wire 91.

[0080] 2, the sixth conductor portion 86 of this embodiment is disposed on the upper surface 131a of the first step portion 131 at a position spaced apart from the first conductor portion 81 and the fourth conductor portion 84. That is, in the example shown in FIG. 2, the sixth conductor portion 86 is electrically independent from each of the first conductor portion 81, the second conductor portion 82, the third conductor portion 83, the fourth conductor portion 84, and the fifth conductor portion 85.

[0081] The seventh conductor portion 87 is disposed on the upper surface 132a of the second step portion 132. The seventh conductor portion 87 is electrically connected to the second electrode 23 of the semiconductor laser element 20 via the thin conductor wire 92 and the joint portion 35. The seventh conductor portion 87 is also electrically connected to the inner layer wiring 15d provided in the main body 11 of the base 10.

[0082] 2, the seventh conductor portion 87 is disposed on the upper surface 132a of the second step portion 132 at a position spaced apart from the third conductor portion 83 and the fifth conductor portion 85. That is, in the example shown in FIG. 2, the seventh conductor portion 87 is electrically independent from each of the first conductor portion 81, the second conductor portion 82, the third conductor portion 83, the fourth conductor portion 84, and the fifth conductor portion 85.

[0083] The third terminal 73 is electrically connected to an external electrode. The external electrode is not shown in FIGS. 1 and 2. The fourth terminal 74 is provided on the main body 11 of the base 10. In the example shown in FIGS. 1 and 2, the fourth terminal 74 is a rod-shaped metal member provided on the side surface 11c on the -Y side of the main body 11. The third terminal 73 and the fourth terminal 74 are arranged spaced apart from each other on the side surface 11c on the same -Y side of the main body 11.

[0084] The fourth terminal 74 extends into the main body 11 and reaches the inner layer wiring 15d. That is, the fourth terminal 74 is electrically connected to the seventh conductor portion 87 via the inner layer wiring 15d. However, the position, size, shape, and other configurations of the fourth terminal 74 are not limited to this.

[0085] The third terminal 73, the sixth conductor portion 86, the seventh conductor portion 87, and the fourth terminal 74 can easily provide a path for the second current flowing from the second power supply through the semiconductor laser element 20 to the external electrode.

[0086] 2, the second current is supplied from the fourth terminal 74, passes through each component that forms the path of the second current, and flows to the third terminal 73. However, the direction of the second current is not limited to this. For example, the second current may be supplied from the third terminal 73, passes through each component that forms the path of the second current, and flows to the fourth terminal 74. That is, the third terminal 73 may be electrically connected to the second power source, and the fourth terminal 74 may be electrically connected to the external electrode.

[0087] [Variation 1] Next, a configuration example of a light emitting device 1A according to Modification 1 of the embodiment will be described with reference to FIGS. 6 and 7. FIG. 6 is a top view schematically showing the light emitting device 1A according to Modification 1. FIG. 7 is a top view schematically showing another example of the light emitting device 1A according to Modification 1. Note that in the light emitting device 1A according to Modification 1, components that are substantially the same as those in the light emitting device 1 according to the embodiment are given the same reference numerals, and descriptions thereof will be omitted as appropriate. In FIGS. 6 and 7, the first power supply, the second power supply, the external detection circuit, and the external electrodes are not shown. In addition, in FIGS. 6 and 7, the light-transmitting member 61 and the folding mirror 65 are not shown.

[0088] In the first modification, the path through which the second current for supplying power to the semiconductor laser element 20 flows is different from that of the embodiment. More specifically, the sixth conductor 86A arranged on the upper surface 131a of the first step portion 131 of the base 10 is electrically connected to at least one of the first conductor 81 and the fourth conductor 84 also arranged on the upper surface 131a of the first step portion 131. In this case, for example, the first conductor 81 and the sixth conductor 86A may be formed integrally. The seventh conductor 87A is arranged at a position spaced apart from the third conductor 83 and the fifth conductor 85.

[0089] At least, the sixth conductor portion 86A is connected to at least one of the first conductor portion 81 and the fourth conductor portion 84, so that a first current flowing from the first power source to the first terminal 71 via the second terminal 72 and a second current flowing from the second power source to the first terminal 71 via the fourth terminal 74 share a part of a current path. Furthermore, the light emitting device 1A does not need to include the third terminal 73 electrically connected to the second power source. This reduces the cost of manufacturing the light emitting device 1A.

[0090] Alternatively, as shown in FIG. 7 , the fourth terminal 74 may not be provided, but the third terminal 73 may be provided, and a portion of the first current may flow from the second terminal 72 to the third terminal 73. As shown in FIG. 7 , the seventh conductor 87A may be electrically connected to at least one of the third conductor 83 and the fifth conductor 85. In this case, for example, the third conductor 83 and the seventh conductor 87A may be integrally formed. The sixth conductor 86A may be disposed at a position spaced apart from the first conductor 81 and the fourth conductor 84. With this structure, a portion of the first current flowing from the first power source to at least one of the third conductor 83A and the fifth conductor 85 via the second terminal 72 can be directed to the seventh conductor 87A. The portion of the first current flowing to the seventh conductor 87A flows to the external electrode via the semiconductor laser element 20, the sixth conductor 86A, and the third terminal 73. That is, a portion of the first current can be diverted as the second current. Furthermore, by connecting at least the seventh conductor portion 87A to at least one of the third conductor portion 83 and the fifth conductor portion 85, a part of the current path is shared between the first current flowing from the first power source to the first terminal 71 via the second terminal 72 and the second current flowing from the first power source to the third terminal 73 via the second terminal 72. Furthermore, the light emitting device 1A does not need to include the fourth terminal 74 electrically connected to the second power source. This reduces the cost of manufacturing the light emitting device 1A.

[0091] [Variation 2] Next, a configuration example of a light emitting device 1B according to Modification 2 of the embodiment will be described with reference to FIGS. 8 and 9. FIG. 8 is a perspective view schematically showing the light emitting device 1B according to Modification 2. FIG. 9 is a top view schematically showing the light emitting device 1B according to Modification 2. Note that in the light emitting device 1B according to Modification 2, components that are substantially the same as those in the above-described embodiment are given the same reference numerals, and descriptions thereof will be omitted as appropriate. In FIGS. 8 and 9, the first power supply, the second power supply, the external detection circuit, and the external electrodes are not shown. In FIG. 9, the light-transmitting member 61 and the folding mirror 65 are not shown.

[0092] In the light emitting device 1B, the configurations of the first terminal 71B, the second terminal 72B, the third terminal 73B, and the fourth terminal 74B are mainly different from the configurations of the first terminal 71, the second terminal 72, the third terminal 73, and the fourth terminal 74 of the light emitting device 1.

[0093] 8 and 9, each of the first terminal 71B, the second terminal 72B, the third terminal 73B, and the fourth terminal 74B is, for example, a film-like conductor. Examples of materials that may be used to form each of the first terminal 71B, the second terminal 72B, the third terminal 73B, and the fourth terminal 74B include single metal materials such as gold, silver, aluminum, nickel, rhodium, copper, titanium, platinum, palladium, molybdenum, chromium, and tungsten, or alloy materials containing these metals.

[0094] The first terminal 71B is electrically connected to, for example, a first power supply. The second terminal 72B is electrically connected to, for example, an external detection circuit. However, the first terminal 71B may be electrically connected to an external detection circuit and the second terminal 72B may be electrically connected to the first power supply. The third terminal 73B is electrically connected to, for example, a second power supply. The fourth terminal 74B is electrically connected to an external electrode. However, the third terminal 73B may be electrically connected to an external electrode and the fourth terminal 74B may be electrically connected to the second power supply.

[0095] The first terminal 71B, the second terminal 72B, the third terminal 73B, and the fourth terminal 74B are disposed on the upper surface 11a of the main body 11 of the base 10. In a top view, the first terminal 71B and the second terminal 72B are disposed on the +Y side of the recess 12. As shown in FIG. 9 , the first terminal 71B is electrically connected to the first conductor 81 via, for example, an inner layer wiring 15e disposed inside the main body 11. The second terminal 72B is electrically connected to the third conductor 83 via, for example, an inner layer wiring 15f disposed inside the main body 11.

[0096] In top view, the third terminal 73B and the fourth terminal 74B are disposed on the −Y side of the recess 12. As shown in FIG. 9 , the third terminal 73B is electrically connected to the sixth conductor 86 via, for example, an inner layer wiring 15g disposed inside the main body 11. The fourth terminal 74B is electrically connected to the seventh conductor 87 via, for example, an inner layer wiring 15h disposed inside the main body 11. The first terminal 71B, the second terminal 72B, the third terminal 73B, and the fourth terminal 74B may each be provided on, for example, the lower surface 11b of the base 10. The first terminal 71B, the second terminal 72B, the third terminal 73B, and the fourth terminal 74B may each be provided on, for example, the side surface 11c of the base 10.

[0097] According to the light emitting device 1B, the first terminal 71B, the second terminal 72B, the third terminal 73B, and the fourth terminal 74B are each formed as a film-like conductor portion disposed on the upper surface 11a of the main body 11 of the base 10, thereby making it possible to reduce the size of the light emitting device 1B in the first direction Y and the second direction X. As a result, the light emitting device 1B can be made more compact. Furthermore, because the first terminal 71B, the second terminal 72B, the third terminal 73B, and the fourth terminal 74B can each be formed on the upper surface 11a by a simple film formation method such as sputtering, the cost of manufacturing the light emitting device 1B can be reduced.

[0098] [Variation 3] Next, a configuration example of a light emitting device 1C according to Modification 3 of the embodiment will be described with reference to Figs. 10 and 11. Fig. 10 is a perspective view schematically showing the light emitting device 1C according to Modification 3. Fig. 11 is a top view schematically showing the light emitting device 1C according to Modification 3. Note that in the light emitting device 1C according to Modification 3, components that are substantially the same as those in the above-described embodiment are given the same reference numerals, and descriptions thereof will be omitted as appropriate. In Figs. 10 and 11, the first power source, the second power source, the external detection circuit, and the external electrodes are not shown.

[0099] In the light emitting device 1C, the configuration of the main body 11M in the base 10M, the configuration of the components that form the path of the first current, and the configuration of the components that form the path of the second current are mainly different from the configuration of the main body 11 in the base 10 in the embodiment, the configuration of the components that form the path of the first current, and the configuration of the components that form the path of the second current.

[0100] Specifically, the main body 11M further includes a plurality of through holes 18 each of which leads to the inside of the recess 12. The first terminal 71M, the second terminal 72M, the third terminal 73M, and the fourth terminal 74M are inserted into the plurality of through holes 18, respectively. As a result, a portion of the first terminal 71M, a portion of the second terminal 72M, a portion of the third terminal 73M, and a portion of the fourth terminal 74M are disposed within the recess 12.

[0101] The main body 11M is preferably made of a single metal material such as gold, silver, aluminum, nickel, rhodium, copper, titanium, platinum, palladium, molybdenum, chromium, tungsten, etc., or an alloy material containing these metals. However, the main body 11M may be made of a material other than a metal, such as a ceramic material such as aluminum nitride, silicon nitride, aluminum oxide, or silicon carbide.

[0102] The first terminal 71M and the first conductor portion 81M are electrically connected via a thin conductor wire 93. The second terminal 72M and the third conductor portion 83M are electrically connected via a thin conductor wire 94. The third terminal 73M and the semiconductor laser element 20 are electrically connected via a thin conductor wire 95. The fourth terminal 74M and the semiconductor laser element 20 are electrically connected via a thin conductor wire 96 and a joint portion 35. In contrast, the light emitting device 1C does not have, for example, the sixth conductor portion 86 and the seventh conductor portion 87 that are provided in the light emitting devices 1, 1A, and 1B.

[0103] The first terminal 71M is electrically connected to, for example, a first power supply. The second terminal 72M is electrically connected to, for example, an external detection circuit. However, the first terminal 71M may be electrically connected to an external detection circuit and the second terminal 72M may be electrically connected to the first power supply. The third terminal 73M is electrically connected to, for example, a second power supply. The fourth terminal 74M is electrically connected to an external electrode. However, the third terminal 73M may be electrically connected to an external electrode and the fourth terminal 74M may be electrically connected to the second power supply.

[0104] According to the light emitting device 1C, a first current can be passed from a first power source to an external detection circuit without providing inner layer wiring in the main body 11M of the base 10M. Also, a second current can be passed from a second power source to an external electrode without providing inner layer wiring in the main body 11M of the base 10M. This simplifies the configuration of the main body 11M, the components that form the path of the first current, and the components that form the path of the second current.

[0105] Although the preferred embodiments have been described in detail above, the present invention is not limited to the above-described embodiments, and various modifications and substitutions can be made to the above-described embodiments without departing from the scope of the claims.

[0106] Aspects of the present disclosure are, for example, as follows. <Item 1> A base body having a main body, a recessed portion provided on an upper surface of the main body, and a step portion provided inside the recessed portion and extending along the inner side surface of the recessed portion between a bottom surface of the recessed portion and an upper surface of the main body in a height direction; a semiconductor laser element disposed between the bottom surface and an upper surface of the step portion in a height direction; a support portion disposed on the bottom surface and supporting the semiconductor laser element; a light reflecting member disposed on the bottom surface at a distance from the support and the semiconductor laser element, the light reflecting member reflecting light emitted from the semiconductor laser element upward; a lens disposed on the upper surface of the step portion so as to be positioned above the light reflecting member, the lens including, in a top view, an area overlapping the upper surface of the step portion and an area overlapping the light reflecting member, a flat portion including an area onto which light reflected by the light reflecting member is incident, and a convex portion located above the flat portion and including an area from which light incident from the flat portion exits; Equipped with When the direction in which the step portion extends is defined as a first direction, When viewed from above, the length of the lens in the first direction is shorter than the length of the lens in a second direction perpendicular to the first direction, At least a part of the semiconductor laser element does not overlap with the lens when viewed from above. Light-emitting device. <Item 2> The length of the lens in the first direction in top view is at least twice the length in the height direction from the bottom surface to the optical axis of the light emitted by the semiconductor laser element. The light emitting device according to <Item 1>. <Item 3> The lens reduces the divergence angle of the component in the first direction of the laser light incident on the flat surface portion of the lens more than the divergence angle of the component in the second direction. The light emitting device according to <Item 1> or <Item 2>. <Item 4> The step portion includes a first step portion and a second step portion provided on either side of the semiconductor laser element, The planar portion of the lens includes, in a top view, a region overlapping an upper surface of the first step portion and a region overlapping an upper surface of the second step portion. The light emitting device according to any one of the above items 1 to 3. <Item 5> The light reflecting member has an area that overlaps with the lens and an area that does not overlap with the lens in a top view. The light emitting device according to any one of <Item 1> to <Item 4>. <Item 6> Further comprising a light-transmitting member overlapping the recess of the base when viewed from above, the semiconductor laser element, the light reflecting member, and the lens are each housed in a space defined by the recess and the light-transmitting member; The light emitting device according to any one of <Item 1> to <Item 5>. <Item 7> A first terminal provided on the main body; a first conductor portion electrically connected to the first terminal and disposed on the upper surface of the first step portion; a second conductor portion electrically connected to the first conductor portion and disposed on a lens side surface that contacts the flat surface portion and the convex surface portion; a third conductor portion electrically connected to the second conductor portion and disposed on the upper surface of the second step portion; a second terminal provided on the main body and electrically connected to the third conductor portion; Further provided with The light emitting device according to <Item 4>. <Item 8> A part of the first conductor portion overlaps with the planar portion in a top view, a portion of the third conductor overlaps with the planar portion in a top view; the portion of the first conductor portion, the portion of the second conductor portion, and the portion of the third conductor portion are arranged in an area of ​​the planar portion excluding an area onto which light reflected by the light reflecting member is incident. The light emitting device according to <Item 7>. <Item 9> A fourth conductor portion disposed between the upper surface of the first step portion and the flat portion and electrically connected to the first conductor portion, the second conductor portion, and the third conductor portion; a fifth conductor portion disposed between the upper surface of the second step portion and the flat portion, and electrically connected to the first conductor portion, the second conductor portion, and the third conductor portion; a sixth conductor portion disposed on the upper surface of the first step portion and electrically independent of the first conductor portion, the second conductor portion, the third conductor portion, the fourth conductor portion, and the fifth conductor portion; a seventh conductor portion disposed on the upper surface of the second step portion and electrically independent of the first conductor portion, the second conductor portion, the third conductor portion, the fourth conductor portion, and the fifth conductor portion; Furthermore, the semiconductor laser element has a first electrode and a second electrode, the sixth conductor is electrically connected to the first electrode of the semiconductor laser element, the seventh conductor portion is electrically connected to the second electrode of the semiconductor laser element; The light emitting device according to <Item 7> or <Item 8>. <Item 10> The upper end of the light reflecting member is below the upper surface of the step portion, The light emitting device according to any one of <Item 1> to <Item 9>. <Item 11> The top of the convex portion of the lens is below the upper surface of the main body of the base, The light emitting device according to any one of <Item 1> to <Item 10>. [Explanation of symbols]

[0107] 1, 1A, 1B, 1C Light-emitting device 10,10M base 11,11M main unit 12 recess 13 Step section 13a Upper surface of stepped portion 131 First Stage 131a Upper surface of the first stage 132 Second Stage 132a Upper surface of second stage 20 Semiconductor laser element 20OA Optical axis of light emitted by semiconductor laser element 20S Light-emitting end face 21 Semiconductor structure 22 1st electrode 23 2nd electrode 30 Support part 35 Joint 40 Light reflecting member 41 Light reflective surface 50 lenses 51 Plane part 52 Convex part 53,54 Lens side 61 Translucent material 65 Folding Mirror 71,71B,71M 1st terminal 72,72B,72M 2nd terminal 73,73B,73M 3rd terminal 74,74B,74M 4th terminal 81,81M First conductor section 82 Second conductor 83,83M Third conductor 84 Fourth conductor 85 5th conductor 86,86A 6th conductor 87,87A 7th conductor

Claims

1. a base body having a main body, a recessed portion provided on an upper surface of the main body, and a step portion provided inside the recessed portion and extending along an inner side surface of the recessed portion between a bottom surface of the recessed portion and an upper surface of the main body in a height direction; a semiconductor laser element that is disposed between the bottom surface and an upper surface of the step portion in a height direction and that emits laser light; a support portion disposed on the bottom surface and supporting the semiconductor laser element; a light reflecting member disposed on the bottom surface at a distance from the support and the semiconductor laser element, the light reflecting member reflecting light emitted from the semiconductor laser element upward; a lens disposed on the upper surface of the step portion so as to be positioned above the light reflecting member, the lens including, in a top view, an area overlapping the upper surface of the step portion and an area overlapping the light reflecting member, a flat portion including an area onto which light reflected by the light reflecting member is incident, and a convex portion located above the flat portion and including an area from which light incident from the flat portion exits; Equipped with When the direction in which the step portion extends is defined as a first direction, When viewed from above, the length of the lens in the first direction is shorter than the length of the lens in a second direction perpendicular to the first direction, When viewed from above, at least a portion of the semiconductor laser element does not overlap with the lens. Light-emitting device.

2. a length of the lens in the first direction in a top view is at least twice the length in a height direction from the bottom surface to an optical axis of light emitted from the semiconductor laser element; The light emitting device according to claim 1 .

3. the lens reduces a divergence angle of a component in the first direction of the laser light incident on the flat surface portion of the lens more than a divergence angle of a component in the second direction of the laser light. The light emitting device according to claim 1 .

4. the step portion includes a first step portion and a second step portion disposed on either side of the semiconductor laser element, the planar portion of the lens includes, in a top view, a region overlapping an upper surface of the first step portion and a region overlapping an upper surface of the second step portion; The light emitting device according to claim 1 .

5. The light reflecting member has an area that overlaps with the lens and an area that does not overlap with the lens in a top view. The light emitting device according to claim 1 .

6. further comprising a light-transmitting member overlapping the recess of the base when viewed from above, the semiconductor laser element, the light reflecting member, and the lens are each housed in a space defined by the recess and the light-transmitting member; The light emitting device according to claim 1 .

7. a first terminal provided on the main body; a first conductor portion electrically connected to the first terminal and disposed on the upper surface of the first step portion; a second conductor portion electrically connected to the first conductor portion and disposed on a lens side surface that contacts the flat surface portion and the convex surface portion; a third conductor portion electrically connected to the second conductor portion and disposed on the upper surface of the second step portion; a second terminal provided on the main body and electrically connected to the third conductor portion; The light emitting device of claim 4 further comprising:

8. a portion of the first conductor overlaps with the planar portion in a top view; a portion of the third conductor overlaps with the planar portion in a top view; the portion of the first conductor portion, the portion of the second conductor portion, and the portion of the third conductor portion are arranged in an area of ​​the planar portion excluding an area onto which light reflected by the light reflecting member is incident. The light emitting device according to claim 7 .

9. a fourth conductor portion disposed between the upper surface of the first step portion and the flat portion and electrically connected to the first conductor portion, the second conductor portion, and the third conductor portion; a fifth conductor portion disposed between the upper surface of the second step portion and the flat portion, and electrically connected to the first conductor portion, the second conductor portion, and the third conductor portion; a sixth conductor portion disposed on the upper surface of the first step portion and electrically independent of the first conductor portion, the second conductor portion, the third conductor portion, the fourth conductor portion, and the fifth conductor portion; a seventh conductor portion disposed on the upper surface of the second step portion and electrically independent of the first conductor portion, the second conductor portion, the third conductor portion, the fourth conductor portion, and the fifth conductor portion; Furthermore, the semiconductor laser element has a first electrode and a second electrode; the sixth conductor is electrically connected to the first electrode of the semiconductor laser element, the seventh conductor portion is electrically connected to the second electrode of the semiconductor laser element; The light emitting device according to claim 7 .

10. an upper end of the light reflecting member is located below the upper surface of the step portion; The light emitting device according to claim 1 .

11. The apex of the convex portion of the lens is below the upper surface of the main body of the base. The light emitting device according to claim 1 .

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