Light-emitting device

Abstract

To provide a light emitting device capable of individually monitoring intensity of light emitted from a plurality of light emitting elements.SOLUTION: A light-emitting device includes a first light-emitting element emitting first light in a first direction, a second light-emitting element emitting second light in a first direction, a substrate, and a cap. The light-emitting device has: a light-extracting surface through which the first light and the second light emitted from the first light-emitting element and the second light-emitting element pass; a package forming a closed space in which the first light-emitting element and the second light-emitting element are placed; one or more optical members positioned away from the light-extracting surface in the first direction and multiplying the first light and the second light; and one or more photodetectors positioned away from the light-extracting surface in the first direction and receiving the first and second light.SELECTED DRAWING: Figure 2

Description

Technical Field

[0004] , , , ,

[0005] , , , , ,

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

Background Art

[0002] A light-emitting device including a plurality of light-emitting elements, a photodetector for monitoring the output of light emitted from the light-emitting elements, and a package on which the plurality of light-emitting elements and the photodetector are mounted is known. Patent Document 1 describes an optical module including a plurality of laser diodes, a multiplexing optical system that multiplexes a plurality of laser lights emitted from the plurality of laser diodes to generate multiplexed light, and a photodiode that detects the intensity of the multiplexed light.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] Provided is a light-emitting device capable of individually monitoring the intensity of light emitted from a plurality of light-emitting elements.

Means for Solving the Problems

[0005] In an exemplary and non-limiting embodiment, the light-emitting device of the present disclosure includes a first light-emitting element that emits first light in a first direction, a second light-emitting element that emits second light in the first direction, a substrate and a cap, and has a light extraction surface through which the first light and the second light emitted from the first light-emitting element and the second light-emitting element pass, and forms a closed space in which the first light-emitting element and the second light-emitting element are disposed. A package, one or more optical members disposed at a position away from the first direction from the light extraction surface for multiplexing the first light and the second light, and one or more photodetectors disposed at a position away from the first direction from the light extraction surface for receiving the first light and the second light. [Effects of the Invention]

[0006] The light-emitting device according to this disclosure provides a light-emitting device that can individually monitor the intensity of light emitted from multiple light-emitting elements. [Brief explanation of the drawing]

[0007] [Figure 1] Figure 1 is a top view of a light-emitting device according to the first embodiment of this disclosure. [Figure 2] Figure 2 is a top view of the light-emitting device according to the first embodiment of this disclosure, with the cap removed. [Figure 3] Figure 3 is a top view of the same state as the top view shown in Figure 2, but with the reflective material removed. [Figure 4] Figure 4 is a cross-sectional view taken along the line IV-IV in Figure 1. [Figure 5] Figure 5 is an enlarged view of the reflective member and photodetector portion of the cross-section shown in Figure 4. [Figure 6] Figure 6 is a cross-sectional view of a light-emitting device further comprising other substrates. [Figure 7] Figure 7 is a cross-sectional view of a variation of the light-emitting device according to the first embodiment of this disclosure. [Figure 8] Figure 8 is a top view of a variation of the light-emitting device according to the first embodiment of this disclosure, with the cap removed. [Figure 9] Figure 9 is a cross-sectional view of a light-emitting device according to a second embodiment of the present disclosure. [Figure 10] Figure 10 is a top view of the light-emitting device according to the second embodiment of this disclosure, with the cap removed. [Figure 11] Figure 11 is an enlarged view of the reflective member and photodetector portion of the cross-section shown in Figure 9. [Figure 12] Figure 12 is a cross-sectional view of a light-emitting device according to the third embodiment of this disclosure. [Figure 13] Figure 13 is a top view of the light-emitting device according to the third embodiment of this disclosure, with the cap removed. [Figure 14] Figure 14 is a cross-sectional view of a light-emitting device according to the fourth to seventh embodiments of this disclosure. [Figure 15] Figure 15 is a top view of the light-emitting device according to the fourth embodiment of this disclosure, with the cap removed. [Figure 16] Figure 16 is a top view of the light-emitting device according to the fifth embodiment of this disclosure, with the cap removed. [Figure 17] Figure 17 is a top view of the light-emitting device according to the sixth embodiment of this disclosure, with the cap removed. [Figure 18] Figure 18 is a top view of the light-emitting device according to the seventh embodiment of this disclosure, with the cap removed. [Figure 19] Figure 19 is a cross-sectional view of a light-emitting device according to the eighth embodiment of this disclosure. [Modes for carrying out the invention]

[0008] In this specification and in the claims, polygons such as triangles and quadrilaterals are not limited to polygons in a mathematically strict sense, but also include shapes in which the corners of a polygon have been rounded, chamfered, or otherwise modified. Furthermore, shapes in which modifications have been made not only to the corners (ends of the sides) but also to the middle parts of the sides are also referred to as polygons. In other words, shapes that retain the shape of a polygon but have been partially modified are included in the "polygons" described in this specification and in the claims.

[0009] This applies not only to polygons, but also to words describing specific shapes such as trapezoids, circles, and concave shapes. The same applies when dealing with each side that forms such a shape. In other words, even if a corner or middle part of a side is processed, the processed part is still included in the definition of "side." When distinguishing a polygon or side without partial processing from a processed shape, the term "strictly" should be added, for example, "strictly quadrilateral."

[0010] In this specification or the claims, when there are multiple elements specified by a certain name and each element needs to be distinguished and expressed, ordinal numbers such as "first", "second", etc. may be appended to the head of each element. For example, when the claim states that "two light-emitting elements are arranged on the substrate", it may be described in the specification as "the first light-emitting element and the second light-emitting element are arranged on the substrate". The ordinal numbers "first" and "second" are used to distinguish the two light-emitting elements. When there is the same name with the same ordinal number between the specification and the claims, the element names with the same ordinal number may not refer to the same element between the specification and the claims. For example, when the specification describes elements specified by the terms "first light-emitting element", "second light-emitting element", and "third light-emitting element", the "first light-emitting element" and "second light-emitting element" in the claims may correspond to the "first light-emitting element" and "third light-emitting element" in the specification. Also, in claim 1 described in the claims, when the term "first light-emitting element" is used and the term "second light-emitting element" is not used, the invention according to claim 1 only needs to include one light-emitting element, and that light-emitting element is not limited to the "first light-emitting element" in the specification and may be the "second light-emitting element" or "third light-emitting element".

[0011] In this specification or the claims, terms indicating a specific direction or position (e.g., "upper", "lower", "right", "left", "front", "rear") may be used. These terms are only used for the sake of clarity of the relative direction or position in the referenced drawings. If the relative direction or position relationship by terms such as "upper" and "lower" in the referenced drawings is the same, in drawings, actual products, manufacturing apparatuses, etc. other than the present disclosure, they do not have to be arranged in the same way as the referenced drawings.

[0012] The dimensions, dimensional ratios, shapes, arrangement intervals, etc. of the elements or members shown in the drawings may be exaggerated for the sake of clarity. Also, to avoid the drawings becoming overly complex, the illustration of some elements may be omitted.

[0013] Embodiments of the present invention will be described below with reference to the drawings. While these embodiments embody the technical concept of the present invention, they do not limit it. The numerical values, shapes, materials, steps, and the order of those steps shown in the description of the embodiments are merely examples, and various modifications are possible as long as they do not create a technical inconsistency. In the following description, elements identified by the same name and reference numerals are identical or of the same type, and redundant explanations of these elements may be omitted.

[0014] <First Embodiment> An example of the configuration of a light-emitting device according to the first embodiment of this disclosure will be described with reference to Figures 1 to 5.

[0015] Figure 1 is a top view of the light-emitting device 100 according to the first embodiment. Figure 2 is a top view of the light-emitting device 100 with the cap 12 removed. Figure 3 is a top view of the top view shown in Figure 2 with the reflective member 60 further removed. Figure 4 is a cross-sectional view taken along the IV-IV cross-sectional line in Figure 1. Figure 5 is an enlarged view of the portion of the cross-section shown in Figure 4 that includes the reflective member 60 and the photodetector 70. In Figures 2 to 5, the light traveling along the optical axis of the light-emitting element 20 is shown by a dashed line. Also, in Figure 5, the reflective member 60 and the photodetector 70 are not hatched for clarity.

[0016] For reference, the drawing shows mutually orthogonal X, Y, and Z axes. The direction of the arrow on the X axis is indicated as the +X direction, and the opposite direction is indicated as the -X direction. If the ±X direction is not distinguished, it is simply referred to as the X direction. The same applies to the ±Y and ±Z directions.

[0017] The light-emitting device 100 according to the first embodiment comprises a package 10, one or more light-emitting elements 20, one or more submounts 30, one or more lens members 40, one or more optical members 50, one or more reflective members 60, and one or more photodetectors 70.

[0018] In the illustrated example of the light-emitting device 100, three light-emitting elements 20 and a submount 30 are arranged in the space inside the package 10, while a lens member 40, an optical member 50, a reflective member 60, and a photodetector 70 are arranged in the space outside the package 10. Light emitted from each of the three light-emitting elements 20 is emitted outwards to the side from the light outlet surface 10B of the cap 12, and then collimated by the lens member 40. Each of the collimated light beams is combined under optical control by the optical member 50, and the combined light is emitted from the light-emitting device 100.

[0019] In the illustrated example of the light-emitting device 100, the size in the X direction is, for example, about 8 mm, the size in the Z direction is, for example, about 10 mm, and the height in the Y direction is, for example, about 4 mm.

[0020] First, let's explain each component.

[0021] (Package 10) The package 10 comprises a substrate 11 having a mounting surface 11M and a cap 12 bonded to the substrate 11. The cap 12 is bonded to the mounting surface 11M of the substrate 11. Other components are also arranged on the mounting surface 11M. As illustrated in other embodiments described later, the cap 12 may be bonded to a different surface on the same side as the mounting surface 11M. The package 10 forms a closed space capable of accommodating other components. This closed space can be sealed in a vacuum or airtight state. In a top view, the outer shape of the cap 12 is encompassed by the outer shape of the substrate 11.

[0022] In the illustrated example, the substrate 11 is flat. The substrate 11 has an upper surface and a lower surface opposite the upper surface. The upper surface can be a mounting surface 11M. The substrate 11 has a first mounting area 11Ma and a second mounting area 11Mb on the upper side. The mounting surface 11M is planar and includes the first mounting area 11Ma and the second mounting area 11Mb. The substrate 11 can be formed mainly from ceramic. Examples of ceramics include aluminum nitride, silicon nitride, aluminum oxide, and silicon carbide.

[0023] The cap 12 includes a side wall portion 12a and an upper portion 12b. The cap 12 has a recess formed by the side wall portion 12a and the upper portion 12b. The outer shape of the cap 12 is rectangular when viewed from above. However, the outer shape of the cap 12 does not have to be rectangular when viewed from above; for example, it may be a polygon other than a quadrilateral or a circle. The substrate 11, the side wall portion 12a, and the upper portion 12b define the closed space of the package 10.

[0024] The first mounting area 11Ma of the substrate 11 is surrounded by the side wall portion 12a when viewed from above. The side wall portion 12a extends above the mounting surface 11M. The second mounting area 11Mb is not surrounded by the side wall portion 12a when viewed from above. The upper portion 12b is located above the mounting surface 11M and is connected to the side wall portion 12a. The upper portion 12b has a lower surface facing the upper surface of the substrate 11. As exemplified in other embodiments described later, the second mounting area 11Mb may be located below (at a lower position than) the first mounting area 11Ma.

[0025] The cap 12 is formed from a translucent material such as glass, plastic, quartz, or sapphire. For example, the cap 12 can be manufactured using processing techniques such as etching. The cap 12 may also be formed by separately forming the upper part 12b and the side wall part 12a using different materials as the main material and then joining them together. For example, the main material of the upper part 12b may be a non-translucent material such as single crystal or polycrystalline silicon, and the main material of the side wall part 12a may be a translucent material such as glass.

[0026] The package 10 is not limited to a structure in which a cap 12 having a side wall portion 12a and an upper portion 12b is bonded to a substrate 11. For example, the package 10 can also be formed by a structure in which a cap having an upper portion 12b is bonded to a substrate having a side wall portion 12a. The package 10 has a lower portion having a first mounting area 11Ma, a side wall portion 12a surrounding the first mounting area 11Ma, and an upper portion 12b facing the lower portion, and it is sufficient that a closed space containing the first mounting area 11Ma is formed.

[0027] The side wall portion 12a has a light-transmitting light incident surface 10A and a light-extracting surface 10B. Of the one or more outer surfaces of the side wall portion 12a, at least one outer surface is the light-extracting surface 10B. Here, "a certain area is translucent" means that the transmittance of the main light incident on that area is 80% or more. The side wall portion 12a may have translucent surfaces other than the light incident surface 10A and the light-extracting surface 10B (inner or outer surfaces). In the illustrated example, the package 10 has four outer surfaces corresponding to the rectangular outer shape of the cap 12, with the light-extracting surface 10B and the outer surface opposite it being translucent, and the remaining two outer surfaces not being translucent.

[0028] The substrate 11 is provided with one or more wiring patterns used for electrical connections between components and a power supply. The wiring patterns can be formed from multiple metal films patterned on the surface of the substrate 11 and via holes connecting these metal films.

[0029] (Light-emitting element 20) The light-emitting element 20 emits light from the light-emitting surface 21. An example of the light-emitting element 20 is a semiconductor laser element. In the illustrated example, the light-emitting element 20 is an end-face emission type semiconductor laser element and may have a rectangular shape when viewed from above. When the light-emitting element 20 is an end-face emission type semiconductor laser element, the side containing one of the two short sides of the rectangle when viewed from above is the light-emitting end face and is the light-emitting surface 21. However, the light-emitting element 20 is not limited to an end-face emission type semiconductor laser element, but may also be a surface-emitting type semiconductor laser element or a light-emitting diode (LED). Furthermore, the light-emitting element 20 may be a single emitter having one emitter, or a multi-emitter having two or more emitters.

[0030] When the light-emitting element 20 is a semiconductor laser element, the light (laser light) emitted from the semiconductor laser element forms an elliptical far-field pattern (hereinafter referred to as "FFP") on a plane parallel to the light-emitting surface 21. FFP is the shape and light intensity distribution of the emitted light at a position away from the light-emitting surface. The ray of the laser beam that passes through the center of the elliptical shape of the FFP is called the optical axis of the laser beam. Light traveling along the optical axis shows a peak intensity in the light intensity distribution of the FFP.

[0031] The light-emitting element 20 can employ a semiconductor laser element that emits blue light. It can also employ a semiconductor laser element that emits green light. Furthermore, it can employ a semiconductor laser element that emits red light. Additionally, it can employ a semiconductor laser element that emits infrared light. Semiconductor laser elements that emit light of other wavelengths may also be used.

[0032] Here, blue light is defined as light whose emission peak wavelength is in the range of 420 nm to 494 nm. Green light is defined as light whose emission peak wavelength is in the range of 495 nm to 570 nm. Red light is defined as light whose emission peak wavelength is in the range of 605 nm to 750 nm. Infrared light is defined as light whose emission peak wavelength is in the range of 780 nm to 2000 nm.

[0033] Examples of semiconductor laser elements that emit blue light or green light include semiconductor laser elements containing nitride semiconductors. Examples of nitride semiconductors that can be used include GaN, InGaN, and AlGaN. Examples of semiconductor laser elements that emit red light or infrared light include those containing InAlGaP, GaInP, GaAs, and AlGaAs semiconductors.

[0034] (Submount 30) The submount 30 has two joining surfaces and a rectangular parallelepiped shape. However, the shape of the submount 30 is not limited to a rectangular parallelepiped. The other joining surface is provided on the opposite side of the first joining surface. The top and bottom surfaces of the submount 30 can each function as two joining surfaces. The submount 30 can be formed from, for example, silicon nitride, aluminum nitride, or silicon carbide. The top surface of the submount 30 may be provided with multiple wiring areas for electrical connection to other components.

[0035] (Lens component 40) The lens member 40 has one or more lens surfaces. The lens surfaces are shaped, for example, to collimate incident light and emit it. The lens member 40 has one or more incident surfaces 41 and one or more exit surfaces 42. Lens surfaces can be formed on the incident surface 41 and / or the exit surfaces 42. In the illustrated example, the lens member 40 has one incident surface 41 and multiple exit surfaces 42. The incident surface 41 is planar, and each of the exit surfaces 42 forms a lens surface.

[0036] The lens member 40 is formed such that multiple lens surfaces are aligned in one direction. In the illustrated example of the lens member 40, the multiple lens surfaces are aligned in the X direction. Examples of lens surfaces are spherical lenses or aspherical lenses. The lens member 40 may be formed from a light-transmitting material, such as glass or plastic or resin.

[0037] (Optical component 50) The optical element 50 emits combined light by coaxially aligning multiple incident light beams. The optical element 50 has one or more optical surfaces. The optical element 50 has a light-reflecting surface 53. An optical control region is provided on the optical surface. The optical control region controls the transmission or reflection of one or more incident light beams. The optical element 50 is realized, for example, by a dichroic mirror. The optical control region may be formed by a dielectric multilayer film having a predetermined wavelength selectivity. The dielectric multilayer film may be formed from, for example, Ta2O5 / SiO2, TiO2 / SiO2, or Nb2O5 / SiO2.

[0038] The optical member 50 has multiple optical surfaces. However, the optical member 50 is not limited to this structure. As illustrated in other embodiments described later, the multiple optical members 50 may each have an optical surface and be arranged spaced apart from each other, thereby aligning multiple incident light beams coaxially and emitting combined light. In other words, one or more optical members 50 align multiple incident light beams coaxially and emit combined light.

[0039] (Reflective member 60) The reflective member 60 has a light-reflecting surface 61 as shown in Figure 5. The reflective member 60 has a structure in which a thin metal film is interposed between two prisms (transparent triangular prisms) and joined together. The reflective member 60 as a whole has a rectangular parallelepiped shape. Note that the reflective member 60 only needs to have a light-reflecting surface 61 and is not limited to the structure shown in the figure. The light-reflecting surface 61 is inclined with respect to the lower surface of the reflective member 60. The light-reflecting surface 61 is composed of a plane that forms an inclination angle of, for example, 40 degrees or more and 50 degrees or less with respect to the lower surface of the reflective member 60.

[0040] (Photodetector 70) The photodetector 70 has a bottom surface and a light-receiving surface 72 located on the opposite side of the bottom surface. The bottom surface can function as a bonding surface to be joined to other components. The photodetector 70 has a rectangular parallelepiped shape. However, it may have a shape other than a rectangular parallelepiped. The length of the light-receiving surface 72 in the X direction is greater than the length of the light-receiving surface in the Z direction. The light-receiving surface 72 has a rectangular shape. However, the shape of the light-receiving surface 72 does not have to be rectangular. One or more light-receiving regions 73 may be provided on the light-receiving surface 72. The photodetector 70 may include, for example, a photoelectric conversion element (photodiode) that outputs an electrical signal corresponding to the intensity or amount of incident light.

[0041] In the illustrated example, the photodetector 70 has a plurality of light-receiving regions 73 on its light-receiving surface 72. The plurality of light-receiving regions 73 are arranged in a line in one direction. Each light-receiving region 73 is provided to receive light of different wavelengths. As illustrated in other embodiments described later, a plurality of photodetectors 70, each having a light-receiving region 73, may receive light of different wavelengths. In other words, one or more photodetectors 70 can receive light of different wavelengths. Note that the wavelengths do not have to be different; for example, the plurality of light-receiving regions 73 may receive light emitted from different light-emitting elements.

[0042] Next, the light-emitting device of the first embodiment will be described.

[0043] (Light-emitting device 100) In the light-emitting device 100, one or more light-emitting elements 20 are arranged on the mounting surface 11M. The one or more light-emitting elements 20 are arranged in the first mounting area 11Ma. The one or more light-emitting elements 20 are bonded to the upper surface of the submount 30. The submount 30 is bonded to the substrate 11. Note that the one or more light-emitting elements 20 may be bonded directly to the substrate 11 without going through the submount 30.

[0044] One or more light-emitting elements 20 are arranged within the enclosed space of the package 10. By hermetically sealing the package 10 under a predetermined atmosphere, quality degradation due to dust collection can be suppressed. Light emitted from one or more light-emitting elements 20 travels laterally and is incident on the light incident surface 10A of the side wall 12a. The light incident on the light incident surface 10A passes through the light exit surface 10B and is emitted laterally.

[0045] In the illustrated example of the light-emitting device 100, when viewed from above, multiple light-emitting elements 20 are arranged in a line in one direction. The multiple light-emitting elements 20 are arranged in the X direction. The multiple light-emitting elements 20 are arranged on one submount 30. Alternatively, multiple submounts 30 may be provided for the multiple light-emitting elements 20, such that only one light-emitting element 20 is arranged on each submount 30. Each light-emitting element 20 emits light that travels in a first direction from its emission end face, and the second direction in which the multiple light-emitting elements 20 are arranged is perpendicular to the first direction when viewed from above. The light emitted from each light-emitting element 20 is emitted from the light extraction surface 10B and travels in the first direction.

[0046] One or more light-emitting elements 20 may be configured to include a first light-emitting element 20a and a second light-emitting element 20b. One or more light-emitting elements 20 may further be configured to include a third light-emitting element 20c. Any of the light-emitting elements 20 may be semiconductor laser elements. In the illustrated light-emitting device 100, the first light-emitting element 20a, the second light-emitting element 20b, and the third light-emitting element 20c are arranged in this order in the -X direction.

[0047] The first light-emitting element 20a emits a first light, La. The second light-emitting element 20b emits a second light, Lb, which is a different color from the first light, La. The third light-emitting element 20c emits a third light, Lc, which is a different color from the first light, La, and the second light, Lb. For example, the first light, La, the second light, Lb, and the third light, Lc are all different colors of light selected from red, green, and blue light, respectively. The second light, Lb, and the third light, Lc may emit light of the same color as the first light, La. For example, the first light, La, may be blue light, the second light, Lb, may be green light, and the third light, Lc, may be red light.

[0048] For example, the first light-emitting element 20a, the second light-emitting element 20b, and the third light-emitting element 20c are all semiconductor laser elements, and the first light La, the second light Lb, and the third light Lc emit blue light with an emission peak wavelength of 460 nm ± 10 nm, green light with an emission peak wavelength of 526 nm ± 11 nm, and red light with an emission peak wavelength of 639 nm ± 10 nm or less. This allows for general coverage of the color gamut defined by the international standard BT.2020, and enables the realization of light suitable for display applications using semiconductor laser elements.

[0049] The first light-emitting element 20a, the second light-emitting element 20b, and the third light-emitting element 20c are arranged with an interval between them in the X direction. In a top view, the light-emitting points of the multiple light-emitting elements 20 are aligned on a straight line parallel to the X direction. The interval between the light-emitting points of two adjacent light-emitting elements 20 can be adjusted, for example, to 200 μm or more and 2000 μm or less.

[0050] The optical axis direction of the second light Lb emitted from the second light-emitting element 20b is parallel to the optical axis direction of the first light La emitted from the first light-emitting element 20a. The optical axis direction of the third light Lc emitted from the third light-emitting element 20c is parallel to the optical axis direction of the first light La emitted from the first light-emitting element 20a. Here, parallelism includes an error of ±2 degrees. The optical axis direction of the light is perpendicular to the emission end face of the light-emitting element 20. The optical axis of the light is parallel to the first direction.

[0051] One or more lens members 40 are located in the second mounting area 11Mb. One or more optical members 50 are located in the second mounting area 11Mb. One or more reflective members 60 and one or more photodetectors 70 are located in the second mounting area 11Mb. The upper ends of the lens members 40, optical members 50, and reflective members 60 are all located above the upper ends of the one or more light-emitting elements 20. By placing components located higher in the Y direction than the light-emitting elements 20 outside the enclosed space, the height of the cap 12 can be reduced, thereby protecting the light-emitting elements 20 and enabling miniaturization of the light-emitting device 100.

[0052] One or more lens members 40 are positioned at a distance from the light extraction surface 10B in a first direction. One or more optical members 50 are positioned at a distance from the light extraction surface 10B in a first direction. One or more photodetectors 70 are positioned at a distance from the light extraction surface 10B in a first direction. One or more lens members 40 and one or more photodetectors 70 are positioned so as not to overlap when viewed from above. One or more optical members 50 and one or more photodetectors 70 are positioned so as not to overlap when viewed from above.

[0053] One or more optical members 50 are positioned further from the light extraction surface 10B (at a distance in the first direction) than one or more lens members 40. One or more photodetectors 70 are positioned further from the light extraction surface 10B (at a distance in the first direction) than one or more optical members 50. One or more reflective members 60 are positioned on top of one or more photodetectors 70. When divergent light is emitted from the light-emitting element 20, the diameter of the light increases as the optical path length increases. Therefore, by positioning the lens members 40 relatively closer to the light extraction surface 10B, the lens members 40 can be miniaturized. This contributes to miniaturizing the light-emitting device 100.

[0054] Light emitted from one or more light-emitting elements 20 and emitted from the light-extraction surface 10B is incident on the incident surface 41 of one or more lens members 40. The light incident on the incident surface 41 is divergent light. One or more lens members 40 emits the light incident on the incident surface 41 as collimated light. The lens surfaces of one or more lens members 40 are provided to collimate the light emitted from one or more light-emitting elements 20. The optical axis of the lens surface coincides with the optical axis of the light emitted from the light-extraction surface 10B and incident on this lens surface. Note that any difference between the two optical axes due to manufacturing tolerances is included in the term "coincides" here.

[0055] In the illustrated example of the light-emitting device 100, the first light La and the second light Lb of the divergent light are incident on one or more lens members 40. The one or more lens members 40 then emit the incident first light La and the second light Lb as collimated first light La and the second light Lb. Furthermore, the third light Lc of the divergent light is incident on one or more lens members 40, and the one or more lens members 40 emit the incident third light Lc as collimated third light Lc. The lens member 40 has one incident surface 41 and three exit surfaces 42 corresponding to the three light-emitting elements 20. In the light-emitting device 100, the light from the three light-emitting elements 20 is collimated by one lens member 40.

[0056] One or more optical members 50 combine the first light La and the second light Lb. One or more optical members 50 further combine these lights, including the third light Lc. One or more optical members 50 combine each of the collimated lights. The combined light Ld is emitted from one or more optical members 50.

[0057] One or more optical members 50 have a first optical surface 52a to which a first light La is incident from a first direction, and a second optical surface 52b to which a second light Lb is incident from the first direction. Furthermore, one or more optical members 50 have a light-reflecting surface 53 that combines the first light La and the second light Lb and emits these lights in the first direction. Additionally, one or more optical members 50 have a third optical surface 52c to which a third light Lc is incident from the first direction. The light-reflecting surface 53 further combines the third light Lc as well, and emits these lights in the first direction. Each optical surface 52a, 52b, and 52c transmits a portion of the light incident from the first direction and reflects the remainder. The reflected light from the light incident from the first direction travels toward the light-reflecting surface 53 and becomes combined light.

[0058] Of the light La, Lb, and Lc incident from the first direction, the light transmitted through the respective optical surfaces 52a, 52b, and 52c is received by the photodetector 70. One or more photodetectors 70 receive the first light La and the second light Lb. One or more photodetectors 70 also receive the third light Lc.

[0059] As shown in Figure 5, in the light-emitting device 100, one or more photodetectors 70 receive light La, Lb, and Lc reflected by one or more reflective members 60 positioned above them. The one or more reflective members 60 have one or more light-reflecting surfaces 61 that reflect light transmitted through one or more optical members 50 downwards.

[0060] One or more photodetectors 70 have a first light-receiving region 73a that receives a first light La, and a second light-receiving region 73b that receives a second light Lb. One or more photodetectors 70 further have a third light-receiving region 73c that receives a third light Lc. In a top view, each light-receiving region 73 is enclosed within one or more reflective members 60.

[0061] The first light-receiving area 73a, the second light-receiving area 73b, and the third light-receiving area 73c are provided on a single light-receiving surface 72. When viewed from above, the first light-receiving area 73a, the second light-receiving area 73b, and the third light-receiving area 73c are aligned in a direction perpendicular to the optical axis direction of the light emitted from each light-emitting element 20 and parallel to the mounting surface 11M, i.e., in the X direction.

[0062] According to the first embodiment of the light-emitting device 100, it is possible to generate light by coaxially combining multiple lights emitted from multiple light-emitting elements 20, and the photodetector 70 makes it possible to individually monitor the intensity of the light emitted from each of the multiple light-emitting elements 20. Furthermore, by mounting the photodetector 70 on the substrate 11 with the light-receiving area 73 facing upwards, the lower surface of the photodetector 70 can be directly used for electrical connection with the substrate 11. In addition, by positioning the lens member 40 close to the light extraction surface 10B, it is possible to contribute to miniaturization of the size of the light-emitting device 100, especially in the Y direction.

[0063] Figure 6 is a cross-sectional view of a light-emitting device 101, which further includes another substrate 19 different from the substrate 11. The cross-sectional view shown in Figure 6 corresponds to the cross-sectional view of the light-emitting device 100 shown in Figure 4. In the light-emitting device 101, the package 10 is formed by joining the cap 12 and the other substrate 19, sealing the space in which the light-emitting element 20 is arranged. The package 10 can be placed on the substrate 11. A first mounting area 11Ma is provided on the upper surface of the other substrate 19, and a second mounting area 11Mb is provided on the upper surface of the substrate 11. In the light-emitting device 101, the package 10 on which the light-emitting element 20 is mounted can be manufactured separately from the substrate 11, thus improving yield.

[0064] (modified version) Examples of variations of the light-emitting device 100 according to the first embodiment will be described with reference to Figures 7 and 8.

[0065] Figure 7 is a cross-sectional view of light-emitting device 102, which is an example of a variation of light-emitting device 100. The cross-sectional view shown in Figure 7 corresponds to the cross-sectional view of light-emitting device 100 shown in Figure 4. Figure 8 is a top view of light-emitting device 102 with the cap 12 removed.

[0066] The light-emitting device 102 differs from the light-emitting device 100 in that it comprises one or more base members 80, and the photodetector 70 is positioned on an inclined support surface of the base member 80. The following description will omit the explanation of the common features and focus mainly on the differences.

[0067] (Base member 80) The base member 80 has a lower surface and a support surface 81 inclined with respect to the lower surface. The support surface 81 is an inclined surface inclined with respect to the lower surface at a certain range of inclination angles. The inclination angle is, for example, in the range of 10 degrees to 80 degrees, and preferably in the range of 40 degrees to 50 degrees. In the illustrated example of the light-emitting device 102, the support surface 81 has an inclination angle of 45 degrees with respect to the lower surface.

[0068] The base member 80 can be formed from, for example, ceramic, glass, or metal. For example, ceramics such as aluminum nitride, glass such as quartz or borosilicate glass, or metals such as aluminum can be used. The base member 80 can also be formed from, for example, silicon.

[0069] In the light-emitting device 102, one or more base members 80 are arranged in the second mounting area 11Mb. The photodetector 70 is placed on the inclined support surface 81 of the base member 80. The upper end of the support surface 81 is located above the upper end of the light-emitting element 20. The light-receiving surface 72 of the photodetector 70 supported on the support surface 81 is inclined with respect to the optical axis direction of the light emitted from each light-emitting element 20. The light-receiving surface 72 is inclined at an angle of, for example, 40 degrees or more and 50 degrees or less with respect to the optical axis direction.

[0070] In one or more photodetectors 70, multiple light-receiving regions 73 are arranged along the X direction. Light La, Lb, and Lc traveling in the first direction are incident on each light-receiving region 73 at an angle other than perpendicular. Even if some of the light is reflected without being received by the light-receiving surface 72, it is possible to reduce the amount of light that is reflected by the light-receiving surface 72 and returns to the light-emitting element 20 because it is incident at an angle other than perpendicular.

[0071] <Second Embodiment> A light-emitting device according to a second embodiment of this disclosure will be described with reference to Figures 9 to 11.

[0072] The light-emitting device according to the second embodiment differs from the light-emitting device according to the first embodiment in that a photodetector 70 is positioned between the light extraction surface 10B and the lens member 40. It also differs in that a reflective member 60A is positioned between the light extraction surface 10B and the lens member 40. Furthermore, it differs in that it does not have a light-reflecting surface 53 and includes an optical member 50A in which the manner of light control by the optical control region of the optical surface differs from that of the optical member 50. The following description will omit the explanation of the common points and will mainly focus on the differences.

[0073] Figure 9 is a cross-sectional view of the light-emitting device 103 according to the second embodiment. The cross-sectional view shown in Figure 9 corresponds to the cross-sectional view of the light-emitting device 100 shown in Figure 4. Figure 10 is a top view of the light-emitting device 103 with the cap 12 removed. Figure 11 is an enlarged view of the portion of the cross-section shown in Figure 9 that includes the reflective member 60A and the photodetector 70.

[0074] (Optical component 50A) Optical component 50A is similar to optical component 50 except that it does not have a light-reflecting surface 53 and the manner in which the light emitted from the light-emitting element 20 is controlled by the light control region is different.

[0075] (Reflective member 60A) The reflective member 60A has a structure in which the light-reflecting surface 61 of the aforementioned reflective member 60 is replaced with a partial reflective surface 63. The partial reflective surface 63 reflects a portion of the incident light and transmits the remainder. The partial reflective surface 63 functions as a beam splitter. Light incident on the partial reflective surface 63 is split into two beams of light, each traveling in a different direction. The two separated beams of light each contain light of the same wavelength. The reflective member 60A splits the same wavelength component of the incident light into two in a predetermined ratio. For example, one of the two beams of light split by the reflective member 60A can be used as the main beam (hereinafter referred to as the "main light"), and the other can be used as a monitoring beam (hereinafter referred to as the "monitor light") to control this main light.

[0076] When incident light is split into main light and monitor light, the intensity of the monitor light is less than the intensity of the main light. The partial reflective surface 63 transmits, for example, 80% to 99.5% of the incident light and reflects 0.5% to 20.0% of the incident light.

[0077] In the light-emitting device 103, one or more photodetectors 70 are positioned closer to the light extraction surface 10B than one or more lens members 40. A reflective member 60A and a photodetector 70 are positioned between the cap 12 and the lens member 40. One or more reflective members 60A are positioned above the light-receiving surfaces 72 of one or more photodetectors 70. Of the light emitted from each light-emitting element 20 and incident on the reflective member 60A, some of the light passes through the partial reflective surface 63 and is incident on the lens member 40, while the remaining light is reflected by the partial reflective surface 63 and reaches the light-receiving surface 72 of the photodetector 70. For example, the light that passes through the partial reflective surface 63 can be used as the main light.

[0078] Light La, Lb, and Lc that have passed through one or more reflective members 60A are combined and emitted by one or more optical members 50A. The combined light Ld travels in a first direction. Light incident on the optical surface of one or more optical members 50A is collimated by one or more lens members 40. In a top view, one or more lens members 40 are positioned between one or more photodetectors 70 and one or more optical members 50A.

[0079] The first optical surface 52a of one or more optical members 50A reflects the first light La incident from the first direction. In the light-emitting device 103, it is not necessary to transmit a portion of the first light La incident from the first direction at the first optical surface 52a in order to deliver light to the photodetector 70. Therefore, the first optical surface 52a only needs to reflect the first light La incident from the first direction. Furthermore, among the optical surfaces, the optical surface that emits the combined light toward the first direction transmits the light incident from the first direction. For example, if there are only the first light La and the second light Lb, the second optical surface 52b transmits the second light Lb incident from the first direction. Also, for example, when the first light La, the second light Lb, and the third light Lc are combined as shown in the figure, the third optical surface 52c transmits the third light Lc incident from the first direction.

[0080] According to the light-emitting device 103 of the second embodiment, the photodetector 70 makes it possible to individually monitor the intensity of light emitted from each of the multiple light-emitting elements 20. Furthermore, by changing the arrangement of the photodetector 70, the light can be combined by an optical element 50A that does not have a light-reflecting surface 53, thereby reducing the size in the X direction and contributing to the miniaturization of the light-emitting device.

[0081] <Third Embodiment> A light-emitting device according to the third embodiment of this disclosure will be described with reference to Figures 12 and 13.

[0082] The light-emitting device according to the third embodiment differs from the light-emitting device according to the second embodiment in that a photodetector 70 is positioned between the lens member 40 and the optical member 50A. The similarities will be omitted below, and the differences will be explained in detail.

[0083] Figure 12 is a cross-sectional view of the light-emitting device 104 according to the third embodiment. The cross-sectional view shown in Figure 12 corresponds to the cross-sectional view of the light-emitting device 100 shown in Figure 4. Figure 13 is a top view of the light-emitting device 104 with the cap 12 removed.

[0084] In the light-emitting device 104, one or more photodetectors 70 are positioned further from the light extraction surface 10B than one or more lens members 40. Also, one or more photodetectors 70 are positioned closer to the light extraction surface 10B than one or more optical members 50A. Compared to the light-emitting device according to the second embodiment, one or more lens members 40 can be positioned closer to the light extraction surface 10B, thus reducing the diameter of the collimated light. This reduces the size in the Y direction and contributes to miniaturization of the light-emitting device.

[0085] The illustrated light-emitting device 104 has a lens member 40 corresponding to each of the multiple light-emitting elements 20. The multiple lens members 40 are arranged in a line in the X direction. A photodetector 70 is provided corresponding to each of the multiple light-emitting elements 20. The multiple photodetectors 70 are arranged in a line in the X direction. A reflective member 60A is provided corresponding to each of the multiple photodetectors 70. In this way, by individually providing a lens member 40 corresponding to each light-emitting element 20, the arrangement of the lens members 40 can be adjusted individually, and the accuracy of collimation can be improved.

[0086] Light La, Lb, and Lc that have passed through one or more reflective members 60A are combined and emitted by one or more optical members 50A. The combined light Ld travels in a first direction. Light incident on the optical surface of one or more optical members 50A is collimated by one or more lens members 40. In a top view, one or more lens members 40 are positioned between one or more photodetectors 70 and one or more optical members 50A.

[0087] <Fourth Embodiment> A light-emitting device according to the fourth embodiment of this disclosure will be described with reference to Figures 14 and 15.

[0088] The light-emitting device according to the fourth embodiment differs from the light-emitting device according to the above embodiment in that the lens member 40 is located in the closed space of the package 10. Hereinafter, the explanation of the common features will be omitted, and the differences will be explained in detail.

[0089] Figure 14 is a cross-sectional view of the light-emitting device 105 according to the fourth embodiment. The cross-sectional view shown in Figure 14 corresponds to the cross-sectional view of the light-emitting device 100 shown in Figure 4. Figure 15 is a top view of the light-emitting device 105 with the cap 12 removed.

[0090] In the light-emitting device 105, one or more lens members 40 are arranged in the closed space of the package 10. Divergent light emitted from one or more light-emitting elements 20 travels in a first direction, enters the one or more lens members 40, and is emitted as collimated light. Collimated light enters the light-entering surface 10A of the package 10, and collimated light is emitted from the light-extracting surface 10B. By not placing a cap 12 between the light-emitting elements 20 and the lens members 40, the lens members 40 can be positioned closer to the light-emitting elements 20, thereby reducing the diameter of the collimated light. This reduces the diameter of the combined light emitted from the light-emitting device.

[0091] <Fifth Embodiment> A light-emitting device according to the fifth embodiment of this disclosure will be described with reference to Figures 14 and 16.

[0092] The light-emitting device according to the fifth embodiment differs from the light-emitting device according to the above-described embodiment in that it includes a fourth light-emitting element 20f. The similarities will be omitted below, and the differences will be explained in detail.

[0093] Figure 14 is a cross-sectional view of the light-emitting device 106 according to the fifth embodiment. The cross-sectional view shown in Figure 14 corresponds to the cross-sectional view of the light-emitting device 100 shown in Figure 4. Figure 16 is a top view of the light-emitting device 106 with the cap 12 removed.

[0094] The light-emitting device 106 includes a fourth light-emitting element 20f. The fourth light-emitting element 20f emits a fourth light, which is infrared light. The light-emitting device 106 includes a plurality of light-emitting elements 20, including the fourth light-emitting element 20f. The plurality of light-emitting elements 20 are arranged in a line in the X direction. In the light-emitting device 106, the fourth light Lf is not combined with the other light La, Lb, and Lc. One or more optical members 50A are not positioned in the optical path of the fourth light Lf.

[0095] In the illustrated light-emitting device 106, the first light-emitting element 20a, the second light-emitting element 20b, the third light-emitting element 20c, and the fourth light-emitting element 20f are arranged in this order in the X direction. Furthermore, the first light La, the second light Lb, and the third light Lc are combined at the third optical surface 52c and emitted in the first direction. Both the combined light Ld and the fourth light Lf travel in the first direction.

[0096] The combined light Ld and the fourth light Lf travel parallel to each other at a close distance. The distance from the position where the first light La, the second light Lb, and the third light Lc are combined to the position where the fourth light intersects with an imaginary line parallel to the X direction passing through this position in a top view is shorter than the distance from the first light-emitting element 20a to the third light-emitting element 20c. In the light-emitting device 106, the combined RGB light and infrared light are emitted at a close distance while being separated from each other. This arrangement is useful when you want to bring the two lights closer together.

[0097] In the light-emitting device 106, one or more photodetectors 70 do not receive the fourth light Lf. One or more photodetectors 70 are not positioned in the optical path of the fourth light Lf when viewed from above. When the first light La, second light Lb, and third light Lc are composed of RGB light and used for a display, and the fourth light Lf is used for detecting position and distance, the balance of the RGB light is adjusted to control the display color, but such adjustment may not be necessary for the infrared light. In such cases, it is desirable to detect the outputs of the first light La, second light Lb, and third light Lc with one or more photodetectors 70, but detection of the output of the fourth light Lf is unnecessary, and the configuration of the light-emitting device 106 can be said to be efficient. The combination of RGB light and infrared light can be used, for example, in automotive headlights or projection mapping onto moving objects.

[0098] <Sixth Embodiment> A light-emitting device according to the sixth embodiment of this disclosure will be described with reference to Figures 14 and 17.

[0099] The light-emitting device according to the sixth embodiment differs from the light-emitting device according to the fifth embodiment in that the position of the fourth light-emitting element 20f is different among the multiple light-emitting elements 20. The similarities will be omitted below, and the differences will be explained in detail.

[0100] Figure 14 is a cross-sectional view of the light-emitting device 107 according to the sixth embodiment. The cross-sectional view shown in Figure 14 corresponds to the cross-sectional view of the light-emitting device 100 shown in Figure 4. Figure 17 is a top view of the light-emitting device 107 with the cap 12 removed.

[0101] In the illustrated light-emitting device 107, the fourth light-emitting element 20f, the first light-emitting element 20a, the second light-emitting element 20b, and the third light-emitting element 20c are arranged in this order in the X direction. Also, at the third optical surface 52c, the first light La, the second light Lb, and the third light Lc are combined and emitted in the first direction. Both the combined light Ld and the fourth light Lf travel in the first direction.

[0102] The combined light Ld and the fourth light Lf travel in parallel. The distance from the point where the first light La, the second light Lb, and the third light Lc are combined to the point where the fourth light intersects with an imaginary line parallel to the X direction passing through this point in a top view is greater than the distance from the first light-emitting element 20a to the third light-emitting element 20c. In the light-emitting device 106, the combined RGB light and the infrared light are emitted at a distance close to the distance between the light-emitting elements 20 located at both ends of the multiple light-emitting elements 20 arranged side by side, while maintaining separation. This arrangement is useful when it is desired to use the two lights separately.

[0103] The illustrated light-emitting device 107 is provided with an optical member 50B having an optical surface corresponding to each of the multiple light-emitting elements 20. The multiple optical members 50B are arranged in a line in the X direction. By providing an optical member 50B individually corresponding to each light-emitting element 20 in this way, the arrangement of the optical members 50B can be adjusted individually, and the accuracy of coaxially combining multiple lights can be improved.

[0104] <Seventh Embodiment> A light-emitting device according to the seventh embodiment of this disclosure will be described with reference to Figures 14 and 18.

[0105] The light-emitting device according to the seventh embodiment differs from the light-emitting device according to the above embodiment in that multiple light-emitting elements 20, including the fourth light-emitting element 20f, are combined. It also differs from the light-emitting device according to the above embodiment in that one or more photodetectors 70 receive the fourth light Lf. Hereinafter, the explanation of the common features will be omitted, and the differences will be explained primarily.

[0106] Figure 14 is a cross-sectional view of the light-emitting device 108 according to the seventh embodiment. The cross-sectional view shown in Figure 14 corresponds to the cross-sectional view of the light-emitting device 100 shown in Figure 4. Figure 18 is a top view of the light-emitting device 108 with the cap 12 removed.

[0107] The light-emitting device 108 includes a fourth light-emitting element 20f. The fourth light-emitting element 20f emits a fourth light, which is infrared light. The light-emitting device 108 includes a plurality of light-emitting elements 20, including the fourth light-emitting element 20f. The plurality of light-emitting elements 20 are arranged in a line in the X direction. In the light-emitting device 108, the fourth light Lf is combined with light emitted from the other light-emitting elements 20.

[0108] In the illustrated light-emitting device 108, the first light-emitting element 20a, the second light-emitting element 20b, the third light-emitting element 20c, and the fourth light-emitting element 20f are arranged in this order in the X direction. One or more optical members 50 have a fourth optical surface 52f. The fourth optical surface 52f transmits the fourth light Lf emitted from the fourth light-emitting element 20f and traveling in the first direction, and combines the first light La, the second light Lb, the third light Lc, and the fourth light Lf. The light Ld combined by the fourth optical surface 52f is emitted in the first direction. In the light-emitting device 108, RGB light and infrared light can be combined and emitted together, so this arrangement is useful when such emitted light is desired.

[0109] <Eighth Embodiment> A light-emitting device according to the eighth embodiment of this disclosure will be described with reference to Figure 19.

[0110] The light-emitting device according to the eighth embodiment differs from the light-emitting device according to the above-described embodiment in that the shape of the substrate 11 is different. The similarities will be omitted below, and the differences will be explained in detail.

[0111] Figure 19 is a cross-sectional view of the light-emitting device 109 according to the seventh embodiment. The cross-sectional view shown in Figure 19 corresponds to the cross-sectional view of the light-emitting device 100 shown in Figure 4. In Figure 19, via wiring passing through the inside of the substrate 11 is shown with dashed lines.

[0112] In the light-emitting device 109, the substrate 11 has a first mounting surface having a first mounting area 11Ma and a second mounting surface having a second mounting area 11Mb. The first mounting surface is located above the second mounting surface. One or more light-emitting elements 20 are arranged in the first mounting area 11Ma, and one or more photodetectors 70 are arranged in the second mounting area 11Mb.

[0113] Furthermore, on the substrate 11, wiring provided on one side of the substrate 11 and wiring provided on another side of the substrate 11 are electrically connected via via wiring that runs through the inside of the substrate 11. On the substrate 11, one or more first wirings 90A provided on the first mounting surface are connected to first wirings 90A provided on the other side via via wiring. One or more second wirings 90B provided on the second mounting surface are connected to second wirings 90B provided on the other side via via wiring. In this way, by realizing two mounting surfaces of different heights with a single substrate 11, the number of components required for manufacturing the light-emitting device, such as submounts, can be reduced. In addition, convenience is improved because electrical connections to the outside can be made to components mounted on either mounting surface via via wiring.

[0114] While embodiments of the present invention have been described above, the light-emitting device according to the present invention is not strictly limited to the light-emitting device of the embodiment. In other words, the present invention is not limited to the external form and structure of the light-emitting device disclosed in the embodiment. Furthermore, it can be applied without requiring all components to be present in sufficient quantities. For example, if some of the components of the light-emitting device disclosed in the embodiment are not described in the claims, a degree of design freedom for those skilled in the art is permitted for those components, such as substitution, omission, modification of shape, or change of material, and the invention described in the claims is then specified to be applicable. [Industrial applicability]

[0115] The light-emitting device according to this embodiment can be used in head-mounted displays, projectors, lighting, displays, and the like. [Explanation of Symbols]

[0116] 10: Package 10A: Light incidence surface 10B: Light extraction surface 11, 19: Circuit board 11M: Implementation side 11Ma: First Implementation Area 11Mb: Second implementation area 11P: Peripheral area 12: Cap 12a: Side wall part 12b: Top 20: Light-emitting element 20a~20c: 1st light-emitting element to 3rd light-emitting element 21:Light exit surface 30: Submount 40: Lens component 41:Incidence plane 42: Ejection surface 50, 50A, 50B: Optical components 52a~51c, 52f: 1st optical surface ~ 4th optical surface 53:Light reflective surface 60, 60A: Reflective material 61:Light reflective surface 63: Partially reflective surface 70: Photodetector 72: Light receiving surface 73: Light receiving area 73a~73c: 1st light receiving area ~ 3rd light receiving area 80: Base component 81: Support surface 90A, 90B: First wiring, second wiring 100-109: Light-emitting device

Claims

1. A first light-emitting element that emits a first light in a first direction, A second light-emitting element that emits a second light in the first direction, A package comprising a substrate and a cap, having a light extraction surface through which the first light and the second light emitted from the first and second light-emitting elements pass, and forming a closed space in which the first and second light-emitting elements are arranged, One or more optical members are arranged at a position away from the light extraction surface in the first direction and combine the first light and the second light, One or more photodetectors are positioned at a distance from the light extraction surface in the first direction and receive the first light and the second light, A light-emitting device equipped with the following features.

2. The system further comprises one or more base members having an inclined surface, The light-emitting device according to claim 1, wherein the one or more photodetectors are arranged on the inclined surface of the one or more base members.

3. The system further comprises one or more reflective members positioned above the one or more photodetectors, which reflect the first light and the second light downwards. The light-emitting device according to claim 1, wherein the one or more photodetectors receive the first light and the second light reflected by the one or more reflective members.

4. The substrate has a mounting surface on which the first light-emitting element and the second light-emitting element are arranged. The cap has the light extraction surface, The light-emitting device according to any one of claims 1 to 3, wherein the one or more optical members are arranged on the mounting surface.

5. The light-emitting device according to any one of claims 1 to 4, wherein the one or more optical members and the one or more photodetectors are arranged in positions that do not overlap when viewed from above.

6. The device further comprises one or more lens members that receive the first divergent light and the second divergent light, and emit them as the first collimated light and the second collimated light, The light-emitting device according to claim 1, wherein the one or more optical members combine the first light of the collimated light and the second light of the collimated light.

7. The light-emitting device according to claim 6, wherein the one or more photodetectors are positioned further from the light extraction surface than the one or more lens members.

8. The light-emitting device according to claim 7, wherein the one or more photodetectors are positioned further from the light extraction surface than the one or more optical members.

9. The light-emitting device according to claim 7, wherein the one or more photodetectors are positioned closer to the light extraction surface than the one or more optical members.

10. The light-emitting device according to any one of claims 6 to 9, wherein the one or more lens members are arranged in the closed space.

11. The light-emitting device according to claim 6, wherein the one or more photodetectors are positioned closer to the light extraction surface than the one or more lens members.

12. The one or more photodetectors include a first light-receiving region for receiving the first light and a second light-receiving region provided separately from the first light-receiving region for receiving the second light. The light-emitting device according to claim 6 or 7, wherein the first light-receiving region and the second light-receiving region are aligned in a direction perpendicular to the optical axis direction of the light emitted from the first light-emitting element, parallel to the mounting surface on which the first light-emitting element is arranged, and facing upward when viewed from above.

13. Further comprising a third light-emitting element that emits a third light in the first direction, The one or more optical members combine the first light, the second light, and the third light, The light-emitting device according to any one of claims 6 to 9, wherein the first light, the second light, and the third light are each different colors of light selected from red light, green light, and blue light.

14. The first light-emitting element, the second light-emitting element, and the third light-emitting element are all semiconductor laser elements. The light-emitting apparatus according to claim 13, wherein the first light, the second light, and the third light are each different colored lights selected from red light with an emission peak wavelength of 639 nm ± 10 nm, green light with an emission peak wavelength of 532 nm ± 5 nm, and blue light with an emission peak wavelength of 460 nm ± 10 nm, respectively.

15. The system further comprises a fourth light-emitting element that emits a fourth light, which is infrared light. The first light-emitting element, the second light-emitting element, the third light-emitting element, and the fourth light-emitting element are arranged in this order in a second direction perpendicular to the first direction when viewed from above. The light-emitting device according to claim 13 or 14, wherein the fourth light is not combined with the first light, the second light, and the third light, and the distance from the position where the first light, the second light, and the third light are combined to the position where the fourth light intersects with a virtual line passing through that position and parallel to the second direction in a top view is shorter than the distance from the first light-emitting element to the third light-emitting element.

16. The system further comprises a fourth light-emitting element that emits a fourth light, which is infrared light. The fourth light-emitting element, the first light-emitting element, the second light-emitting element, and the third light-emitting element are arranged in this order in a second direction perpendicular to the first direction when viewed from above. The light-emitting device according to claim 13 or 14, wherein the fourth light is not combined with the first light, the second light, and the third light, and the distance from the position where the first light, the second light, and the third light are combined to the position where the fourth light intersects with a virtual line passing through that position and parallel to the second direction in a top view is greater than the distance from the first light-emitting element to the third light-emitting element.

17. The system further comprises a fourth light-emitting element that emits a fourth light, which is infrared light. The light-emitting device according to claim 13 or 14, wherein the one or more optical members combine the first light, the second light, the third light, and the fourth light.

Images