Light-emitting device

Abstract

To provide a compact light emitting device.SOLUTION: A light emitting device of the present disclosure includes: a first light emitting element having a first light emission surface emitting first light along a first optical axis; a second light emitting element which is arranged at a position where a virtual plane that is parallel to the first light emission surface and passes the first light emitting element passes, the position being away from the first light emitting element in a first direction perpendicular to the first optical axis, and which has a second light emission surface emitting second light along a second optical axis relatively tilted from the first optical axis in a second direction opposite to the first direction; and a third light emitting element which is arranged at a position where the virtual plane passes, the position being away from the first light emitting element in the second direction, and which has a third light emission surface emitting third light along a third optical axis relatively tilted from the first optical axis in the first direction.SELECTED DRAWING: Figure 6A

Description

[Technical field]

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

[0002] A light-emitting device has been developed that includes a plurality of light-emitting elements that each emit light with a different central wavelength. Patent Document 1 discloses a light-emitting device in which a plurality of semiconductor laser elements and a collimating lens through which the laser light emitted from each semiconductor laser element passes are arranged. This light-emitting device is an optical pickup device that focuses laser light selectively emitted from each of a plurality of semiconductor laser elements with different oscillation wavelengths onto a CD or DVD. In this light-emitting device, the positions at which the plurality of semiconductor laser elements are arranged are adjusted so as to correct the deviation of the focal position. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] JP 2001-291259 A Summary of the Invention [Problem to be solved by the invention]

[0004] There is a demand for miniaturization of light emitting devices that include a plurality of light emitting elements. [Means for solving the problem]

[0005] In one embodiment, the light emitting device of the present disclosure comprises: a first light emitting element having a first light emitting surface that emits a first light along a first optical axis; a second light emitting element having a second light emitting surface that is arranged at a position through which a virtual plane that is parallel to the first light emitting surface and passes through the first light emitting element, and is spaced from the first light emitting element in a first direction perpendicular to the first optical axis, and emits a second light along a second optical axis that is inclined relatively from the first optical axis in a second direction that is opposite to the first direction; and a third light emitting element having a third light emitting surface that is arranged at a position through which the virtual plane passes, and is spaced from the first light emitting element in the second direction, and emits a third light along a third optical axis that is inclined relatively from the first optical axis in the first direction. Effect of the Invention

[0006] According to the light emitting device of the present disclosure, the points of incidence of light emitted from multiple light emitting elements on the incident surface of the lens member can be brought closer together than when multiple light emitting elements are arranged in parallel, making it possible to miniaturize the light emitting device. [Brief description of the drawings]

[0007] [Figure 1] FIG. 1 is a perspective view of a light emitting device according to the first and second embodiments. [Diagram 2] FIG. 2 is a perspective view of the light emitting device according to the first embodiment with a package cap removed. [Diagram 3] FIG. 3 is a top view of the light emitting device according to the first embodiment with the cap of the package removed. [Figure 4] 4 is a cross-sectional view of the light emitting device taken along the line IV-IV in FIG. [Diagram 5] FIG. 5 is an enlarged top view of the inside of the package according to the first embodiment. [Figure 6A] FIG. 6A is a top view that typically illustrates the optical axis of each of a plurality of light-emitting elements and the light emitted from each light-emitting element along the optical axis. [Figure 6B] FIG. 6B is a top view diagrammatically illustrating the angles of the optical axes of the plurality of light-emitting elements. [Figure 7A] FIG. 7A is a diagram illustrating a schematic positional relationship between emission points of a first light, a second light, and a third light. [Figure 7B] FIG. 7B is a diagram illustrating a schematic positional relationship between the points of incidence of the first light, the second light, and the third light on the incidence surface of the lens member. [Figure 8] FIG. 8 is a perspective view of the light emitting device according to the second embodiment with the cap of the package removed. [Figure 9A] FIG. 9A is a top view showing an example of the shape of a submount on which a plurality of light emitting elements are mounted in the second embodiment. [Figure 9B] FIG. 9B is a top view showing an example of the arrangement relationship of the emission points of the multiple light-emitting elements 20 in the second embodiment. [Figure 10] FIG. 10 is a perspective view of the light emitting device according to the third embodiment. [Figure 11] FIG. 11 is a top view of the light emitting device according to the third embodiment with the cap of the package removed. [Figure 12] FIG. 12 is a perspective view of the light emitting device according to the fourth embodiment. [Figure 13] FIG. 13 is a perspective view of the light emitting device according to the fourth embodiment with the cover removed. [Figure 14] FIG. 14 is a perspective view of the light emitting device according to the fourth embodiment with the second cap and the lid member removed. [Figure 15] FIG. 15 is a top view of the light emitting device according to the fourth embodiment with the second cap and the lid member removed. [Figure 16] FIG. 16 is a perspective view of a substrate included in the light emitting device according to the fourth embodiment. [Figure 17] FIG. 17 relates to a light emitting device according to a fourth embodiment and is a cross-sectional view of the light emitting device taken along the line XVII-XVII in FIG. [Figure 18] FIG. 18 is a side view of the light emitting device according to the fourth embodiment with the second cap and the lid member removed, as viewed from the lid member side. [Figure 19]FIG. 19 relates to a light emitting device according to a fifth embodiment and is a cross-sectional view of the light emitting device taken along the line XVII-XVII in FIG. [Figure 20] FIG. 20 is a perspective view of a substrate included in the light emitting device according to the fifth embodiment. [Figure 21] FIG. 21 is a schematic side view of a head mounted display including a light emitting device according to an embodiment of the present disclosure. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0008] In this specification and claims, polygons such as triangles and quadrangles are not limited to polygons in the strict mathematical sense, but also include shapes in which the corners of the polygon have been processed, such as rounded corners, chamfered corners, or rounded corners. In addition, shapes in which processing has been applied to the middle part of a side, not just the corners (edges) of a polygon, are also referred to as polygons. In other words, shapes in which partial processing has been applied while leaving the polygon as the base are included in the "polygon" described in this specification and claims.

[0009] This is not limited to polygons, but also applies to words that describe specific shapes such as trapezoids, circles, and irregular shapes. The same is true when dealing with each side that forms the shape. In other words, even if the corners or middle part of a side have been processed, the "side" includes the processed part. When distinguishing a "polygon" or "side" that has no processing from a processed shape, the word "strict" should be added, for example, "strict quadrangle."

[0010] In this specification or claims, when there are multiple elements identified by a certain name and each element is to be expressed separately, an ordinal number such as "first" or "second" may be added to the beginning of each element. For example, if a claim states that "light-emitting elements are arranged on a substrate," the specification may state that "a first light-emitting element and a second light-emitting element are arranged on a substrate." The ordinal numbers "first" and "second" are used simply to distinguish between two light-emitting elements. The order of these ordinal numbers has no special meaning. Element names with the same ordinal number may not refer to the same element between the specification and the claims. For example, when elements specified by the terms "first light-emitting element", "second light-emitting element", and "third light-emitting element" are described in the specification, 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. In addition, when the term "first light-emitting element" is used but the term "second light-emitting element" is not used in claim 1 described in the claims, the invention according to claim 1 may have only one light-emitting element, and the light-emitting element is not limited to the "first light-emitting element" in the specification, but may be the "second light-emitting element" or the "third light-emitting element".

[0011] In this specification or claims, terms indicating a specific direction or position (e.g., "upper", "lower", "right", "left", "front", "rear" and other terms including these terms) may be used. These terms are used merely for the purpose of making it easier to understand the relative direction or position in the referenced drawings. As long as the relationship of the relative direction or position by terms such as "upper" and "lower" in the referenced drawings is the same, the drawings other than those of this disclosure, the actual product, the manufacturing device, etc. may not be arranged in the same manner as in the referenced drawings.

[0012] The dimensions, dimensional ratios, shapes, spacing, etc. of elements or components shown in the drawings may be exaggerated for clarity. Also, in order to avoid the drawings becoming overly complicated, some elements may be omitted from the drawings.

[0013] Hereinafter, an embodiment of the present invention will be described with reference to the drawings. Although the embodiment embodies the technical idea of ​​the present invention, it does not limit the present invention. The numerical values, shapes, materials, steps, and the order of the steps shown in the description of the embodiment are merely examples, and various modifications are possible as long as no technical contradiction occurs. In the following description, elements identified by the same name and symbol are the same or similar elements, and duplicate descriptions of those elements may be omitted.

[0014] First Embodiment A light emitting device 100 according to a first embodiment will be described. FIGS. 1 to 7B are diagrams for explaining an exemplary embodiment of the light emitting device 100. FIG. 1 is a perspective view of the light emitting device 100. FIG. 2 is a perspective view of the light emitting device 100 with the cap 16 of the package 10 removed. FIG. 3 is a top view in the same state as FIG. 2. FIG. 4 is a cross-sectional view taken along the IV-IV cross-sectional line in FIG. 1. FIG. 5 is an enlarged top view of the inside of the package 10. FIG. 6A is a top view that diagrammatically illustrates the optical axes of the light emitting elements 20 and the light emitted from each light emitting element 20 along the optical axis. FIG. 6B is a top view that diagrammatically illustrates the angle of the optical axis of each light emitting element. FIG. 7A is a diagram diagrammatically illustrating the positional relationship of the incident points of the first light, the second light, and the third light on the incident surface of the lens member 40. FIG. 7B is a diagram diagrammatically illustrating the positional relationship of the emission points of the first light, the second light, and the third light on the emission surface of the lens member 40.

[0015] The light emitting device 100 includes a plurality of components including a package 10, one or more light emitting elements 20, one or more submounts 30, a lens member 40, one or more protection elements 60A, a temperature measuring element 60B, a plurality of wirings 70, and a substrate 90. The light emitting device 100 may also include a plurality of light emitting elements 20. The light emitting device 100 may also include a plurality of protection elements 60A.

[0016] In the illustrated example of the light emitting device 100, three light emitting elements 20, a submount 30, three protective elements 60A, a temperature measuring element 60B, and a plurality of wirings 70 are arranged in the space inside the package 10. The light emitted from the three light emitting elements 20 is respectively emitted to the outside from the package 10 and then enters the lens member 40. The light emitted from the three light emitting elements 20 is collimated by the lens member 40.

[0017] First, each component will be described.

[0018] (Package 10) The package 10 has a base 11 including a mounting surface 11M, and a side wall 12. When viewed from above, the outer shape of the package 10 is rectangular. The outer shape of the package 10 does not have to be rectangular, and may be, for example, a polygon other than a square, a circle, or the like.

[0019] The mounting surface 11M is a flat surface, and one or more components of the light emitting device 100 are arranged on the mounting surface 11M. The sidewall portion 12 surrounds the mounting surface 11M and extends above the mounting surface 11M. The one or more components arranged on the mounting surface 11M are surrounded by the sidewall portion 12. The package 10 further has a top surface portion. The top surface portion is connected to the sidewall portion 12 above the mounting surface 11M. The top surface portion is located directly above the one or more components arranged on the mounting surface 11M.

[0020] The package 10 has a plurality of wiring regions 14 for electrical connection. The plurality of wiring regions 14 are provided on the mounting surface 11M. Note that in Figs. 3 and 5, each wiring region 14 is hatched. The plurality of wiring regions 14 may be electrically connected to a wiring region provided on the lower surface of the base 11 (the surface opposite the mounting surface 11M) through via holes passing through the inside of the base 11. The wiring region electrically connected to the wiring region 14 is not limited to being provided on the lower surface of the base 11, but may also be provided on another outer surface (upper surface or outer surface) of the package 10.

[0021] The package 10 has a light extraction surface 10A. The light extraction surface 10A can be one of one or more outer surfaces constituting the side wall portion 12. The light extraction surface 10A stands perpendicular to the mounting surface 11M. The light extraction surface 10A can be perpendicular to a plane parallel to the mounting surface 11M. Note that the perpendicular here includes a difference of ±5 degrees or less. The light extraction surface 10A may be inclined with respect to a plane parallel to the mounting surface 11M.

[0022] At least a part of the light extraction surface 10A has light-transmitting properties. This light-transmitting region is called a light-transmitting region 13 (see FIG. 4 for reference numeral 13). Here, the term "having light-transmitting properties" means that the region has a transmittance of 80% or more for the main light incident thereon. The light-transmitting region 13 may extend across multiple outer surfaces of the package 10.

[0023] The light-transmitting region in the package 10 is not limited to the light-transmitting region 13. For example, a light-transmitting region may be provided on a surface different from the light extraction surface 10A, separated from the light-transmitting region 13. The package 10 may have a non-light-transmitting region (a region that does not have light-transmitting properties).

[0024] In the illustrated example of the package 10, only one of the multiple outer surfaces of the side wall portion 12 is the light extraction surface 10A. The package 10 has four outer surfaces corresponding to a rectangular outer shape, and all four surfaces are translucent.

[0025] The package 10 can be composed of a substrate 15 and a cap 16 fixed to the substrate 15. Other components may also be included. The substrate 15 has a base 11, and the cap 16 has a side wall 12 and a top surface. The substrate 15 has a flat plate shape. The cap 16 has a concave shape with a depression. The outer shape of the cap 16 is rectangular when viewed from above. The outer shape of the cap 16 does not need to be rectangular, and may be, for example, a polygon other than a square, or a circle.

[0026] The cap 16 is bonded to the substrate 15 to form the internal space of the package 10. A peripheral region 11P is provided on the mounting surface 11M of the substrate 15. The peripheral region 11P is provided around the region on the mounting surface 11M in which other components are arranged. A plurality of wiring regions 14 are surrounded by the peripheral region 11P. The cap 16 is bonded to the peripheral region 11P of the substrate 15. A metal film for bonding may be arranged in the peripheral region 11P. The internal space of the package 10 is a sealed space. The internal space of the package 10 is in an airtight state.

[0027] The cap 16 can be made of, for example, a light-transmitting material. Only the side wall portion 12 of the cap 16 may be made of a light-transmitting material. For example, the upper surface portion may be made of a non-light-transmitting material.

[0028] The substrate 15 may be formed mainly from ceramic. Examples of the ceramic that may be the main material of the substrate 15 include aluminum nitride, silicon nitride, aluminum oxide, and silicon carbide. The substrate 15 may be formed from a ceramic substrate having a plurality of metal vias therein. The plurality of wiring regions 14 may be formed from a conductor such as a metal, and may be a patterned metal film.

[0029] The cap 16 can be made from a light-transmitting material such as glass, plastic, or quartz by using a processing technique such as molding or etching. The cap 16 may be formed by forming the top surface portion and the side wall portion 12 using different materials as the main materials and bonding them together. For example, the top surface portion can be made mainly of single crystal or polycrystalline silicon, and the side surface portion can be made mainly of glass.

[0030] The internal space of package 10 is not limited to being formed by a flat-plate-shaped member having mounting surface 11M and a concave-shaped member, such as substrate 15 and cap 16. For example, the internal space of package 10 may be formed by a concave-shaped member having mounting surface 11M and a flat-plate-shaped member. Also, for example, the internal space of package 10 may be formed by two concave-shaped members, one of which has mounting surface 11M.

[0031] Hereinafter, in order to distinguish between substrate 15 and substrate 90, they may be referred to as first substrate 15 and second substrate 90, respectively.

[0032] (Light emitting element 20) An example of the light-emitting element 20 is a semiconductor laser element. The light-emitting element 20 may have a rectangular outer shape when viewed from above. When the light-emitting element 20 is an edge-emitting semiconductor laser element, a side surface intersecting one of the two short sides of the rectangle is a light-emitting end surface (light-emitting surface 23). The light-emitting element 20 emits light from the light-emitting surface 23. In this example, the upper and lower surfaces of the light-emitting element 20 have a larger area than the light-emitting surface 23. The light-emitting element 20 is not limited to an edge-emitting semiconductor laser element, and may be a surface-emitting semiconductor laser element or a light-emitting diode (LED). In the illustrated example of the light-emitting device 100, an edge-emitting semiconductor laser element is used as the light-emitting element 20.

[0033] The light-emitting element 20 is, for example, a single-emitter element having one emitter. The light-emitting element 20 may be a multi-emitter element having two or more emitters. When the light-emitting element 20 is a semiconductor laser element having multiple emitters, one common electrode can be provided on one of the upper and lower surfaces of the light-emitting element 20, and electrodes corresponding to the respective emitters can be provided on the other surface.

[0034] The light emitted from the light emitting surface 23 of the light emitting element 20 is divergent light having a spread. However, it does not have to be divergent light. 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. The FFP refers to the shape and light intensity distribution of the emitted light at a position away from the light emitting surface.

[0035] The light passing through the center of the elliptical shape of the FFP, in other words, the light with the peak intensity in the light intensity distribution of the FFP, is called the light traveling along the optical axis. Also, the optical path of the light traveling along the optical axis is called the optical axis of that light. Also, in the light intensity distribution of the FFP, the light with a peak intensity of 1 / e 2 Light having an intensity equal to or greater than this will be referred to as the "major portion" of light.

[0036] In the elliptical shape of the FFP of light emitted from the light emitting element 20, which is a semiconductor laser element, the minor axis direction of the ellipse is called the "slow axis direction" and the major axis direction is called the "fast axis direction." A plurality of layers, including an active layer, constituting the semiconductor laser element can be stacked in the fast axis direction.

[0037] Based on the light intensity distribution of the FFP, 1 / e 2 The angle corresponding to the intensity of the laser beam is defined as the divergence angle of the light from the semiconductor laser element. The main part of the light emitted from the semiconductor laser element can be said to be divergent light that spreads at this divergence angle. The divergence angle of the light in the fast axis direction is sometimes called the perpendicular divergence angle, and the divergence angle of the light in the slow axis direction is sometimes called the parallel divergence angle.

[0038] For example, a light emitting element that emits blue light, a light emitting element that emits green light, or a light emitting element that emits red light can be used as the light emitting element 20. Furthermore, a light emitting element that emits light other than these may also be used.

[0039] Here, blue light refers to light whose emission peak wavelength is in the range of 420nm to 494nm, green light refers to light whose emission peak wavelength is in the range of 495nm to 570nm, and red light refers to light whose emission peak wavelength is in the range of 605nm to 750nm.

[0040] Examples of semiconductor laser elements that emit blue light or green light include semiconductor laser elements that include nitride semiconductors. Examples of nitride semiconductors that can be used include GaN, InGaN, and AlGaN. Examples of semiconductor laser elements that emit red light include those that include InAlGaP, GaInP, GaAs, and AlGaAs semiconductors.

[0041] (Submount 30) The submount 30 has two bonding surfaces and is configured in a rectangular parallelepiped shape. One bonding surface is provided on the opposite side to the other bonding surface. The distance between the two bonding surfaces is smaller than the distance between the other two opposing surfaces. The shape of the submount 30 does not have to be limited to a rectangular parallelepiped. The submount 30 can be formed using, for example, aluminum nitride or silicon carbide. A metal film for bonding is provided on the bonding surfaces.

[0042] (Lens member 40) The lens member 40 is formed with one or more lens surfaces. The lens member 40 collimates the incident light. For example, the one or more lens surfaces are designed to convert the light diverging from the focal position into collimated light by refraction and emit the collimated light from the lens member 40. The lens surface is spherical or aspherical. The lens surface is formed on the light incident side surface and / or the light exit side surface of the lens member 40. In the illustrated example of the lens member 40, a concave lens surface is formed on the light incident side, and a convex lens surface is formed on the light exit side. Note that a plurality of lens surfaces may be formed on the light incident side surface, and the lens member 40 may form one or more lens surfaces on the light incident side surface. Also, a plurality of lens surfaces may be formed on the light exit side surface, and the lens member 40 may form one or more lens surfaces on the light exit side surface.

[0043] The lens member 40 may be formed from a light-transmitting material, such as glass or plastic. The shape of the portion of the lens member 40 through which light does not transmit may be arbitrary, but it is preferable that the lens member 40 has a shape that allows it to be fixed to another component. In the illustrated example of the lens member 40, when the lens member 40 is disposed so that the optical axis extends in a direction parallel to the lower surface, the lens member 40 has a flat lower surface, and this lower surface may function as a bonding surface.

[0044] (Protection element 60A) The protective element 60A is a circuit element for preventing an excessive current from flowing through a specific element (for example, the light emitting element 20) and causing the element to be destroyed. A typical example of the protective element 60A is a constant voltage diode such as a Zener diode. A Si diode can be used as the Zener diode.

[0045] (Temperature measuring element 60B) The temperature measuring element 60B is an element used as a temperature sensor for measuring the surrounding temperature. For example, a thermistor can be used as the temperature measuring element 60B.

[0046] (Wiring 70) The wiring 70 is composed of a conductor having a linear shape with joints at both ends. In other words, the wiring 70 has joints at both ends of the linear portion that are joined to other components. The wiring 70 is, for example, a metal wire. Examples of metals include gold, aluminum, silver, copper, etc.

[0047] (Second substrate 90) The second substrate 90 has a mounting surface 90M. The second substrate 90 has a plurality of wiring regions. The plurality of wiring regions can be provided on the mounting surface 90M. The wiring regions of the second substrate pass through the inside of the second substrate 90 and are electrically connected to a wiring region provided on the lower surface (the surface opposite to the mounting surface 90M) of the second substrate 90. The wiring region electrically connected to the wiring region located on the upper surface (mounting surface 90M) of the second substrate 90 can be provided not only on the lower surface of the second substrate 90 but also on other outer surfaces (upper surface and outer side surfaces) of the second substrate 90.

[0048] The second substrate 90 may be formed mainly from ceramic. Examples of ceramics that may be used for the second substrate 90 include aluminum nitride, silicon nitride, aluminum oxide, and silicon carbide.

[0049] The second substrate 90 preferably includes a portion formed from a material having better heat dissipation properties (a material with high thermal conductivity) than ceramic. In the example of the second substrate 90, the second substrate 90 may have a thermally conductive member embedded therein. This thermally conductive member fills an opening penetrating from the upper surface to the lower surface of the second substrate 90. The thermally conductive member is provided in a region facing the lower surface of the first substrate 15. The thermally conductive member may be formed from, for example, a metal. The thermally conductive member may have any shape.

[0050] The second substrate 90 has a structure that supports the components of the light emitting device 100 and can be electrically connected to electronic components included in these components. The second substrate 90 may support elements other than the components of the light emitting device 100, electronic components, or optical components.

[0051] (Light emitting device 100) Next, the light emitting device 100 will be described.

[0052] In the light emitting device 100, one or more light emitting elements 20 are disposed in the internal space of the package 10. For example, if the internal space of the package 10 is hermetically sealed, deterioration of the quality of the light emitting element 20 due to dust collection can be suppressed. Such a sealing structure is preferable when the light emitting element 20 is, for example, a semiconductor laser element. Note that the light emitting element 20 does not necessarily have to be disposed in a sealed internal space.

[0053] The one or more light-emitting elements 20 are disposed on the mounting surface 11M. The one or more light-emitting elements 20 emit light toward the side wall portion 12. The light emitted from the light emission surface 23 of the one or more light-emitting elements 20 is each emitted from the light-transmitting region 13 of the light extraction surface 10A.

[0054] In the illustrated light emitting device 100, a plurality of light emitting elements 20 are arranged on a mounting surface 11M. The plurality of light emitting elements 20 emit light having different peak wavelengths. The plurality of light emitting elements 20 emit light having different colors. The plurality of light emitting elements 20 include a first light emitting element 20a, a second light emitting element 20b, and a third light emitting element 20c. The first light emitting element 20a is located in the center, and the second light emitting element 20b and the third light emitting element 20c are located on either side of the first light emitting element 20a.

[0055] The one or more light-emitting elements 20 are arranged side by side with the light emission surface 23 facing the light extraction surface 10A. Light traveling along an optical axis emitted from the one or more light-emitting elements 20 travels from the light extraction surface 10A in a direction parallel to the mounting surface 11M. Here, "parallel" includes a difference of ±3 degrees or less. The light extraction surface 10A is perpendicular to the optical axis along which the light emitted from the light-emitting element 20 travels. The light extraction surface 10A does not have to be perpendicular to the optical axis along which the light emitted from the one or more light-emitting elements 20 travels.

[0056] In the illustrated light-emitting device 100, the light extraction surface 10A is perpendicular to the optical axis (hereinafter referred to as the first optical axis 21a) along which the light (hereinafter referred to as the first light 22a) emitted from the first light-emitting element 20a travels. The first light 22a and the first optical axis 21a are illustrated in FIG. 6A.

[0057] Next, referring to FIG. 6A and FIG. 6B, an example of the arrangement of the plurality of light-emitting elements 20 will be described in more detail in relation to the lens member 40. The first light-emitting element 20a has a first light emission surface 23a that emits the first light 22a along the first optical axis 21a. The first optical axis 21a is preferably parallel to the optical axis of the lens member 40, and more preferably coincides with the optical axis of the lens member 40. In the illustrated example, the first optical axis 21a coincides with the optical axis of the lens member 40. In the present disclosure, the two optical axes being coincident is defined as the two optical axes being parallel and the center-to-center distance between the two optical axes being 0.1 mm or less. When the first light 22a travels along the first optical axis 21a, it spreads in a direction perpendicular to the first optical axis 21a.

[0058] The second light emitting element 20b is disposed at a position where a virtual plane VR that is parallel to the first light emitting surface 23a of the first light emitting element 20a and passes through the first light emitting element 20a passes. More specifically, the second light emitting element 20b is disposed at a position where the virtual plane VR passes and away from the first light emitting element 20a in a first direction S1 perpendicular to the first optical axis 21a. The second light emitting element 20b has a second light emitting surface 23b that emits light (hereinafter referred to as second light 22b) along an optical axis (hereinafter referred to as second optical axis 21b) that is inclined relatively from the first optical axis 21a in a second direction S2 that is opposite to the first direction S1. When the second light 22b travels along the second optical axis 21b, it spreads in a direction perpendicular to the second optical axis 21b.

[0059] The third light emitting element 20c is disposed at a position through which the virtual plane VR passes, and at a position away from the first light emitting element 20a in a second direction S2 (a direction anti-parallel to the first direction S2) perpendicular to the first optical axis 21a. The third light emitting element 20c has a third light emitting surface 23c that emits light (hereinafter referred to as third light 22c) along an optical axis (hereinafter referred to as third optical axis 21c) that is inclined relatively from the first optical axis 21a to the first direction S1. When the third light 22c travels along the third optical axis 21c, it spreads in a direction perpendicular to the third optical axis 21c.

[0060] 6A shows a first exit point 24a from which the first light 22a traveling along the first optical axis 21a is emitted on the first light emitting surface 23a, a second exit point 24b from which the second light 22b traveling along the second optical axis 21b is emitted on the second light emitting surface 23b, and a third exit point 24c from which the third light 22c traveling along the third optical axis 21c is emitted on the third light emitting surface 23c. In this example, the distances between the virtual plane VR and each of the first exit point 24a, the second exit point 24b, and the third exit point 24c are approximately equal. As will be described later, the light emitting device of the present disclosure is not limited to this example.

[0061] FIG. 6B shows a virtual straight line 212 that is parallel to the first optical axis 21a and extends from the second emission point 24b. The angle θ2 between the virtual straight line 212 and the second optical axis 21b defines the inclination of the second optical axis 21b with respect to the first optical axis 21a. When a counterclockwise rotation (rotation in a plane parallel to the mounting surface 11M) is defined as a "positive" rotation and a clockwise rotation is defined as a "negative" rotation in a top view, the angle θ2 has a negative value. The absolute value of the angle θ2 (|θ2|) is in the range of more than 0 degrees and not more than 30 degrees. A preferable range of the absolute value of the angle θ2 is, for example, 3 degrees or more and not more than 15 degrees.

[0062] 6B shows a virtual line 213 that is parallel to the first optical axis 21a and extends from the third emission point 24c. The angle θ3 between the virtual line 213 and the third optical axis 21c defines the inclination of the third optical axis 21c with respect to the first optical axis 21a. According to the above definition, the angle θ3 has a positive value. The value of the angle θ3 (equal to the absolute value |θ3| of the angle θ3) is in the range of more than 0 degrees and not more than 30 degrees. A preferable range of the angle θ3 is, for example, 3 degrees or more and not more than 15 degrees.

[0063] The difference between the absolute value of the angle θ2 and the absolute value of the angle θ3 is in the range of 0 degrees or more and 5 degrees or less. In the illustrated light emitting device 100, the absolute value of the angle θ2 and the absolute value of the angle θ3 are equal. That is, the difference is 0 degrees. In this case, "equal" includes a difference of 1 degree or less. The distance d2 from the first emission point 24a to the second emission point 24b is equal to the distance d3 from the first emission point 24a to the third emission point 24c. In this case, "equal" includes a difference of 50 μm or less. In addition, the distance d2 and the distance d3 do not necessarily have to be equal, but it is preferable that the difference between the distance d2 and the distance d3 is within 300 μm. The smaller the difference in distance, the smaller the angle difference, making it easier to perform optical control by the lens member 40, etc. The second optical axis 21b and the third optical axis 21c are in a symmetrical relationship or a roughly symmetrical relationship with respect to the first optical axis 21a. The distances from the first light output point 24a, the second light output point 24b, and the third light output point 24c to the virtual plane VR are equal. Note that "equal" here includes a difference of 20 μm or less. The distance L2 from the second light output surface 23b to the light incident surface 42 of the lens member 40 is approximately equal to the distance L3 from the third light output surface 23c to the light incident surface 42 of the lens member 40. Note that, as described later, depending on the arrangement of the three light-emitting elements 20, the absolute value of the angle θ2 and the absolute value of the angle θ3 may be different.

[0064] The peak wavelengths of the first light 22a, the second light 22b, and the third light 22c are referred to as the first peak wavelength, the second peak wavelength, and the third peak wavelength, respectively. In the light emitting device 100, the first light 22a, the second light 22b, and the third light 22c can be lights of different colors selected from red light, green light, and blue light, respectively.

[0065] As an example, the first light emitting element 20a emits a first light 22a of green, and the two light emitting elements 20b, 20c disposed on both sides of the first light emitting element 20a emit a second light 22b of red and a third light 22c of blue, respectively. The configuration in which the three light emitting elements 20 emit three colors of light, RGB, in this manner can be adopted, for example, for color image display. Note that the color of light emitted by each light emitting element 20 is not limited to this, and is not limited to visible light.

[0066] In the light emitting device 100, the first light 22a traveling along the first optical axis 21a and the second light 22b traveling along the second optical axis 21b intersect in an optical path between the incident surface 42 and the exit surface 44 of the lens member 40 in a top view. The first light 22a traveling along the first optical axis 21a and the third light 22c traveling along the third optical axis 21c intersect in an optical path between the incident surface 42 and the exit surface 44 of the lens member 40 in a top view. The second light 22b traveling along the second optical axis 21b and the third light 22c traveling along the third optical axis 21c intersect in an optical path between the incident surface 42 and the exit surface 44 of the lens member 40 in a top view.

[0067] On the incident surface 42 of the lens member 40, the first incident point 25a where the first light 22a traveling along the first optical axis 21a is incident, the second incident point 25b where the second light 22b traveling along the second optical axis 21b is incident, and the third incident point 25c where the third light 22c traveling along the third optical axis 21c is incident are closer to each other than the first exit point 24a where the first light 22a traveling along the first optical axis 21a is emitted on the first light exit surface 23a, the second exit point 24b where the second light 22b traveling along the second optical axis 21b is emitted on the second light exit surface 23b, and the third exit point 24c where the third light 22c traveling along the third optical axis 21c is emitted on the third light exit surface 23c.

[0068] In the example shown in FIG. 7A, the distance between the first emission point 24a, the second emission point 24b, and the third emission point 24c that are the farthest apart is a distance d OUT The distance d OUT is the sum of the above-mentioned distance d2 and distance d3. On the other hand, in the example shown in FIG. 7B, the distance between the farthest incident points among the first incident point 25a, the second incident point 25b, and the third incident point 25c is the distance d IN According to this embodiment, the distance d IN distance d OUT The distance d can be made shorter than IN For example, the distance d IN is the distance d OUTThe minimum value may be, for example, 0 μm. IN The distance d = 0 μm means that the first incident point 25a, the second incident point 25b, and the third incident point 25c are all located at one point. IN is the distance d OUT The distance d can be less than half of OUT has a size of, for example, 0 μm or more and 1000 μm or less.

[0069] Thus, the distance d IN The effect of shortening the distance d makes it possible to bring the incident point of each light emitted from the multiple light-emitting elements 20 arranged at different positions closer to the optical axis of the lens member 40. By bringing it closer to the optical axis, the precision of optical control can be improved. For example, generally, when the incident point of light deviates from the optical axis of the lens member 40, it becomes more susceptible to the influence of spherical aberration. According to this embodiment, it is possible to make the incident point of each light emitted from the multiple light-emitting elements 20 coincide with or come closer to the optical axis of the lens member 40. In addition, the distance d IN By shortening this time, when a color image is formed using the light emitting device of this embodiment as a light source, it is possible to reduce pixel shifts for each color.

[0070] In the example of Fig. 7A, the first emission point 24a, the second emission point 24b, and the third emission point 24c are shown to be at the same vertical position (height from the mounting surface 11M), but the embodiment of the present disclosure is not limited to this example. Similarly, in the example of Fig. 7B, the first incidence point 25a, the second incidence point 25b, and the third incidence point 25c are shown to be at the same vertical position, but the embodiment of the present disclosure is not limited to this example.

[0071] In the light emitting device 100, one or more light emitting elements 20 are disposed on one or more submounts 30. The submount 30 is bonded to the light emitting element 20 at one bonding surface, and is bonded to the mounting surface 11M at the other bonding surface on the opposite side. Note that the one or more light emitting elements 20 may be disposed directly on the mounting surface 11M without the submount 30. In the illustrated example of the light emitting device 100, multiple light emitting elements 20 are disposed on one submount 30.

[0072] In the light emitting device 100, one or more protective elements 60A are disposed inside the package 10. Each protective element 60A is disposed on the mounting surface 11M. Each protective element 60A is disposed in a different wiring region 14. The protective element 60A protects the light emitting element 20. In the illustrated example of the light emitting device 100, multiple protective elements 60A are provided in a one-to-one relationship for multiple light emitting elements 20.

[0073] In the light emitting device 100, the temperature measuring element 60B is disposed inside the package 10. The temperature measuring element 60B is disposed on the mounting surface 11M. The temperature measuring element 60B is disposed in the wiring region 14 where the protection element 60A is not disposed. The temperature measuring element 60B is provided in the light emitting device 100 for the purpose of measuring the temperature of the light emitting element 20.

[0074] In the light emitting device 100, the wiring 70 is joined to the wiring region 14 of the package 10 on the side of the light emitting element 20 (the side including the surface opposite to the light emitting surface 23 of the light emitting element 20) with a straight line parallel to the light emitting surface 23 of the light emitting element 20 as a boundary in a top view. This makes it easier to prevent the wiring 70 from entering the optical path of light.

[0075] In the light emitting device 100, the package 10 is disposed on the second substrate 90. The bottom surface of the package 10 is mounted on a mounting surface 90M of the second substrate 90, and the package 10 is supported by the second substrate 90. The bottom surface of the package 10 may also be the bottom surface of the first substrate 15.

[0076] Each of the light emitting element 20, the protection element 60A, and the temperature measuring element 60B is electrically connected to the second substrate 90 via the wiring region 14. Furthermore, each of the light emitting element 20, the protection element 60A, and the temperature measuring element 60B can be electrically connected to an external circuit of the light emitting device 100 via a plurality of wiring regions of the second substrate 90.

[0077] In the light emitting device 100, the second substrate 90 has a length in a direction perpendicular to the first direction S1 greater than the length in a direction parallel to the first direction S1 in a top view. The length of the long side of the second substrate 90 can be 1.5 to 3 times the length of the short side. Although details will be described later, when the light emitting device 100 is mounted on the head mounted display 600 as shown in FIG. 21, it is preferable that the length in the direction parallel to the first direction S1 and the second direction S2 is short.

[0078] Hereinafter, in order to distinguish between mounting surface 11M of first substrate 15 and mounting surface 90M of second substrate 90, they may be referred to as first mounting surface 11M and second mounting surface 90M, respectively.

[0079] In the light emitting device 100, the lens member 40 is disposed on the second substrate 90. The lens member 40 is mounted on the second mounting surface 90M, and is supported by the second substrate 90. The lens member 40 may also be mounted on the first substrate 15. With reference to the light emitting device 100 shown in the drawings, for example, if the first substrate 15 is made the same size as the second substrate 90 and is expanded to the position where the lens member 40 is disposed, the lens member 40 can be mounted on the first substrate 15.

[0080] The lens member 40 is disposed outside the package 10. Therefore, the lens member 40 is not surrounded by the side wall portion 12. By not disposing the lens member 40 in the internal space of the package 10, the size of the package 10 in the height direction (the direction perpendicular to the first mounting surface 11M) can be reduced, which can contribute to miniaturization of the light emitting device 100.

[0081] The lens member 40 is subjected to light emitted from one or more light-emitting elements 20 and emitted from the light extraction surface 10A to the outside of the package 10. The entire main portion of the light emitted from the one or more light-emitting elements 20 is incident on the lens member 40. Furthermore, a portion of the light emitted from the one or more light-emitting elements 20 other than the main portion may also be incident on the lens member 40.

[0082] Light emitted from one or more light-emitting elements 20 and emitted from the light-transmitting region 13 to the outside of the package 10 enters the lens member 40 and is emitted from one lens surface. The light from one or more light-emitting elements 20 that enters the entrance surface of the lens member 40 becomes collimated light and is emitted from the exit surface of the lens member 40. The light from one or more light-emitting elements 20 that enters the entrance surface of the lens member 40 becomes collimated in the fast axis direction and is emitted from the exit surface of the lens member 40. Collimating the light from the multiple light-emitting elements 20 with one lens surface can narrow the interval between the light-emitting elements 20, which can contribute to the miniaturization of the light-emitting device 100.

[0083] The lower surface of the lens member 40 is below the plane including the first mounting surface 11M. A part of the main portion of light emitted from the light extraction surface 10A passes below the plane including the first mounting surface 11M at a position closer to the light extraction surface 10A than the incident surface of the lens member 40. By bonding the package 10 and the lens member 40 to the second substrate 90, the lower surface of the lens member 40 can be located at a position lower than the first mounting surface 11M, and light traveling at a position lower than the plane including the first mounting surface 11M can be made incident on the lens member 40.

[0084] The optical axis of the lens surface of the lens member 40 from which light is emitted and the optical axis of the light extracted from the light extraction surface 10A are at the same height from the first mounting surface 11M of the base 11. The optical axis of the lens surface of the lens member 40 from which light is emitted is perpendicular to the first direction S1 and the second direction S2 described above.

[0085] In the illustrated example of the light emitting device 100, the light emitted from the multiple light emitting elements 20 is collimated in at least the fast axis direction (direction perpendicular to the first mounting surface 11M) and is emitted from the lens member 40 as collimated light. The lens member 40 has one lens surface that collimates the first light 22a, the second light 22b, and the third light 22c. In this example, the optical axis of the first light 22a (first optical axis 21a) coincides with the optical axis of the lens member 40.

[0086] <Second embodiment> A light emitting device 200 according to the second embodiment will be described. A perspective view of the light emitting device 200 is shown in FIG. 1, similar to the perspective view of the light emitting device 100. FIG. 8 is a perspective view of the light emitting device 200 with the cap 16 of the package 10 removed. FIG. 9A is a top view showing an example of the shape of a submount on which a plurality of light emitting elements 20 are mounted. FIG. 9B is a top view showing an example of the arrangement of the emission points of the plurality of light emitting elements 20.

[0087] Similar to the light emitting device 100, the light emitting device 200 comprises a number of components including a package 10, one or more light emitting elements 20, one or more submounts 30, a lens member 40, one or more protection elements 60A, a temperature measuring element 60B, a number of wirings 70, and a substrate 90.

[0088] The submount 30 in the light emitting device 200 has a side surface 31 that intersects with the top surface 30T. The submount 30 has side surfaces 32, 33, and 34 in addition to the side surface 31. In the illustrated example, the top surface of the submount 30 is a parallelogram with a non-90 degree apex angle, and the side surfaces 31 and 33 that face each other are parallel, and the side surfaces 32 and 34 that face each other are also parallel. The shape of the top surface of the submount does not need to be a parallelogram, and may be a rhombus, trapezoid, scalene polygon, or the like. When the shape of the top surface of the submount is a parallelogram, the submount base material can be efficiently used when the submount is separated from the submount base material, thereby preventing an unnecessary increase in material costs.

[0089] The first light-emitting element 20a, the second light-emitting element 20b, and the third light-emitting element 20c are arranged so that a first emission point 24a from which a first light 22a traveling along the first optical axis 21a is emitted on the first light emitting surface 23a, a second emission point 24b from which a second light 22b traveling along the second optical axis 21b is emitted on the second light emitting surface 23b, and a third emission point 24c from which a third light 22c traveling along the third optical axis 21c is emitted on the third light emitting surface 23c protrude from an outer edge 30E located at the boundary between the upper surface 30T and the side surface 31 of the submount 30.

[0090] In top view, the direction of the first optical axis 21a and the direction in which the outer edge 30E extends intersect at an angle other than 90°. In other words, of the four side surfaces 31, 32, 33, and 34 that the submount 30 has, the side surface 31 facing the lens member 40 is not perpendicular to the direction of the first optical axis 21a. In top view, the absolute value of the inclination angle θe of the side surface 31 with respect to a line N perpendicular to the first optical axis 21a is greater than 0 degrees, and is, for example, equal to or less than 45 degrees.

[0091] 9B, in this embodiment, the distance Z1 from the imaginary plane VR to the first emission point 24a of the first light-emitting element 20a is longer than the distance Z2 from the imaginary plane VR to the second emission point 24b of the second light-emitting element 20b. Also, the distance Z1 from the imaginary plane VR to the first emission point 24a of the first light-emitting element 20a is shorter than the distance Z3 from the imaginary plane VR to the third emission point 24c of the third light-emitting element 20c.

[0092] Since each of the first emission point 24a, the second emission point 24b, and the third emission point 24c protrudes toward the lens member 40 from the outer edge 30E located at the boundary between the upper surface 30T and the side surface 31 of the submount 30, it is possible to prevent a part of the light emitted from each emission point 24a, 24b, 24c and spreading from hitting the submount 30 (vignetting). The longer the protruding distance of each emission point 24a, 24b, 24c from the side surface 31 of the submount 30, the smaller the contact area between each light emitting element 20a, 20b, 20c and the submount 30. The larger the contact area, the easier it is to conduct heat generated in the light emitting elements 20a, 20b, 20c to the outside via the submount 30, so it is preferable that the contact area is large. Therefore, the protruding distance of each of the emission points 24a, 24b, 24c from the outer edge 30E located at the boundary between the upper surface 30T and the side surface 31 of the submount 30 can be set within the range of, for example, 0 μm to 50 μm.

[0093] In the example shown in FIG. 9A and FIG. 9B, the distance from the light incident surface 42 of the lens member 40 to the first emission point 24a is different from the distance from the light incident surface 42 of the lens member 40 to the second emission point 24b, and also different from the distance from the light incident surface 42 of the lens member 40 to the third emission point 24c. According to this embodiment, when the focal length of the lens member 40 varies depending on the wavelength of light, it is possible to arrange the first emission point 24a, the second emission point 24b, and the third emission point 24c according to the respective focal lengths. In an example, the difference between the distance Z1 and the distance Z2 can be set within a range of, for example, 5 μm or more and 60 μm or less. Also, the difference between the distance Z1 and the distance Z3 can be set within a range of, for example, 5 μm or more and 60 μm or less.

[0094] In this way, when the positions of the first exit point 24a, the second exit point 24b, and the third exit point 24c in the direction of the optical axis of the lens member 40 are different, the difference between the absolute value of the inclination (angle θ2) of the second optical axis 21b from the first optical axis 21a and the absolute value of the inclination (angle θ3) of the third optical axis 21c from the first optical axis 21a may be 0 degrees, but is preferably greater than 0 degrees. When the distance d2 and the distance d3 are equal, the first optical axis 21a, the second optical axis 21b, and the third optical axis 21c can be made to intersect at the "same position" by making the absolute value of the angle θ2 and the absolute value of the angle θ3 different. Note that even when the distance d2 and the distance d3 are different, the first optical axis 21a, the second optical axis 21b, and the third optical axis 21c can be made to intersect at the "same position" by adjusting the absolute value of the angle θ2 and the absolute value of the angle θ3, respectively.

[0095] In this way, the absolute value of angle θ2 and the absolute value of angle θ3, which define the relationship between the inclinations of the first optical axis 21a, the second optical axis 21b, and the third optical axis 21c, can take values ​​according to the lens characteristics, such as the focal length of the lens member 40, which is determined by the peak wavelength of light traveling along each optical axis.

[0096] According to the light emitting device 200 of the present embodiment, the positions at which the first light 22a, the second light 22b, and the third light 22c enter the lens member 40 can be brought closer to each other, and the positions of the light emission points can be adjusted to reduce chromatic aberration caused by the lens member 40. As a result, in a display using the light emitting device 200 as a light source, it becomes easier to suppress blurring of pixels of each color on the imaging surface.

[0097] <Third embodiment> A light emitting device 300 according to a third embodiment will be described. Figures 10 and 11 are diagrams for explaining an exemplary embodiment of the light emitting device 300. Figure 10 is a perspective view of the light emitting device 300. Figure 11 is a top view of the light emitting device 300 with a package cap removed.

[0098] The light emitting device 300 has the same components as the light emitting device 100, and further has a light control unit 50 that can make the optical axes 21a, 21b, and 21c of the first light 22a, the second light 22b, and the third light 22c that have passed through the lens member 40 parallel, preferably coaxial.

[0099] The light control unit 50 controls the first light 22a, the second light 22b, and the third light 22c that are incident so that their optical axes are parallel and at least some of the light overlaps with each other, and then emits the light. The light control unit 50 controls the first light 22a, the second light 22b, and the third light 22c that have traveled along optical axes that are not parallel to each other so that they travel along optical axes that are parallel to each other. In the illustrated example, the light control unit 50 includes a plurality of optical members (reference numerals 55a, 55b, 56, and 57 in the figure). The light control unit 50 performs optical control that combines selective reflection and selective transmission using the plurality of optical members, and can align the optical axes of the light beams in parallel. In addition, the light control unit 50 makes it possible to output the first light 22a, the second light 22b, and the third light 22c as coaxial light.

[0100] The light control unit 50 is configured to receive the first light 22a, the second light 22b, and the third light 22c that have passed through the lens member 40, and to emit the first light 22a, the second light 22b, and the third light 22c whose first optical axis 21a, the second optical axis 21b, and the third optical axis 21c are parallel to each other.

[0101] In the light emitting device 300, the first light 22a traveling along the first optical axis 21a and the second light 22b traveling along the second optical axis 21b intersect at an optical path length longer than the optical path length to reach the exit surface 44 of the lens member 40 in a top view. The first light 22a traveling along the first optical axis 21a and the third light 22c traveling along the third optical axis 21c intersect at an optical path length longer than the optical path length to reach the exit surface 44 of the lens member 40 in a top view. The second light 22b traveling along the second optical axis 21b and the third light 22c traveling along the third optical axis 21c intersect at an optical path length longer than the optical path length to reach the exit surface 44 of the lens member 40 in a top view.

[0102] In the light emitting device 100, the first light 22a traveling along the first optical axis 21a and the second light 22b traveling along the second optical axis 21b intersect in an optical path between the emission point of the lens member 40 and the incidence point of the light control unit 50 in a top view. The first light 22a traveling along the first optical axis 21a and the third light 22c traveling along the third optical axis 21c intersect in an optical path between the incidence point of the lens member 40 and the emission point of the light control unit 50 in a top view. The second light 22b traveling along the second optical axis 21b and the third light 22c traveling along the third optical axis 21c intersect in an optical path between the incidence point of the lens member 40 and the emission point of the light control unit 50 in a top view.

[0103] The second light 22b traveling along the second optical axis 21b of the second light emitting element 20b arranged at a position away from the first light emitting element 20a in the first direction S1 is incident on the light control unit 50 at a position away from the first optical axis 21a in the second direction S2. The third light 22c traveling along the third optical axis 21c of the third light emitting element 20c arranged at a position away from the first light emitting element 20a in the second direction S2 is incident on the light control unit 50 at a position away from the first optical axis 21a in the first direction S1.

[0104] By providing an intersection point of the optical axes of multiple lights between the lens member 40 and the light control unit 50 when viewed from above, the distance between the optical axes of two lights when they enter the light control unit 50 can be narrowed compared to when they intersect before passing through the lens member 40.

[0105] In this embodiment, the light beams traveling along optical axes that intersect with each other when viewed from above have different peak wavelengths, and therefore multiple surfaces that have different reflection or transmission characteristics according to the wavelength are arranged to make the optical axes parallel to each other.

[0106] The configuration of the light control unit 50 that performs such a function is not particularly limited, but for example, as shown in the figure, the light control unit 50 includes a plurality of optical members each having a flat plate shape. In the example of the light emitting device 300 shown in the figure, the light control unit 50 includes two first optical members 55a and 55b, a second optical member 56, and a third optical member 57.

[0107] The multiple light beams incident on the light control unit 50 are each light beams having different peak wavelengths. Alternatively, the multiple light beams incident on the light control unit 50 are each light beams having different colors. A plurality of optical members are used to form a plurality of regions (light control regions) that selectively perform optical control on the multiple light beams.

[0108] The light control region can be formed on the surface of the optical member, preferably on a flat and smooth surface. For example, the light control region can be formed by depositing a dielectric multilayer film by a thin film deposition technique such as sputtering on the surface (main surface) of a transparent body of the optical member made of a transparent material such as glass or plastic that transmits visible light. The optical member can be formed by, for example, a dichroic mirror.

[0109] In the light emitting device 300, the light control unit 50 is disposed on the second substrate 90. The light control unit 50 is mounted on the second mounting surface 90M and supported by the second mounting surface 90M. The light control unit 50 may be mounted on the first substrate 15.

[0110] Light emitted from the multiple light emitting elements 20 is incident on the light control unit 50. Multiple light beams whose optical axes are not parallel to each other are incident on the light control unit 50. Light that has passed through the lens member 40 and is collimated is incident on the light control unit 50.

[0111] The light control regions of the light control unit 50 are inclined with respect to a straight line parallel to the first optical axis 21a in a top view. The angle of this inclination can be set in the range of, for example, 35° to 70°.

[0112] The optical members (55a, 55b, 56, 57) of the light control unit 50 are arranged in a diagonal direction with respect to the first optical axis 21a in a top view. In the illustrated example, two adjacent optical members satisfy the relationship that, in a top view, one optical member is not arranged on a straight line that passes through the light control area of ​​one optical member and is parallel to the light control area, and one optical member is not arranged on a virtual straight line that passes through the light control area of ​​the other optical member. This relationship is satisfied for all optical members that form the light control area. Arranging multiple optical members of similar shapes side by side makes it easier to implement.

[0113] In the illustrated example of the light emitting device 300, the first light 22a, the second light 22b, and the third light 22c that have passed through one lens surface of the lens member 40 are incident on the light control unit 50. The light control unit 50 includes four optical members 55a, 55b, 56, and 57, and emits the first light 22a, the second light 22b, and the third light 22c whose optical axes are parallel to one another.

[0114] The light control unit 50 includes two first optical members 55a and 55b, a second optical member 56, and a third optical member 57. At least four light control regions are formed by the two first optical members 55a and 55b. Here, the four light control regions are distinguished by being called a first region 51, a second region 52, a third region 53, and a fourth region 54, respectively.

[0115] Each of the two first optical members 55a, 55b has a first surface facing the lens member 40 and a second surface opposite thereto. Four light control regions are provided on the first and second surfaces of the two first optical members 55a, 55b.

[0116] The third region 53 is formed on a first surface of the first optical member 55a, and the first region 51 is formed on a second surface. The second region 52 and the fourth region 54 are provided on different surfaces of the same first optical member 55b. The second region 52 is formed on the first surface of the first optical member 55b, and the fourth region 54 is formed on the second surface.

[0117] The second optical member 56 has a reflecting surface 56M. The third optical member 57 has a reflecting surface 57M. The reflecting surfaces 56M and 57M are disposed opposite each other with the two first optical members 55a and 55b in between. The two first optical members 55a and 55b are disposed between a plane including the reflecting surface 56M of the second optical member 56 and a plane including the reflecting surface 57M of the third optical member 57.

[0118] The first region 51 reflects the first light 21a and transmits the third light 21c. The second region 52 reflects the first light 21a and transmits the second light 21b. The third region 53 reflects the second light 21b, transmits the first light 21a, and transmits the third light 21c. The fourth region 54 reflects the third light 21c, transmits the first light 21a, and transmits the second light 21b. The reflecting surface 56M reflects the second light 21b. The reflecting surface 57M reflects the third light 21c.

[0119] The above-mentioned configuration example of the light control unit 50 is merely one example, and the light control unit 50 may have other configurations. By employing a light control unit that controls the optical axis of light transmitted through the lens member 40 according to the color of the light, when the light emitting device is used as a light source for a display, for example, alignment with the optical axis of various optical systems used in the display becomes easy.

[0120] <Fourth embodiment> A light emitting device 400 according to a fourth embodiment will be described. FIGS. 12 to 18 are diagrams for explaining an exemplary embodiment of the light emitting device 400. FIG. 12 is a perspective view of the light emitting device 400. FIG. 13 is a perspective view of the light emitting device 400 with the lid member removed. FIG. 14 is a perspective view of the light emitting device 400 with the second cap removed from the state of FIG. 13, and FIG. 15 is a top view of the light emitting device 400 with the second cap and the lid member removed from the state of FIG. 13. FIG. 16 is a perspective view of a substrate provided in the light emitting device 400. FIG. 17 is a cross-sectional view taken along the XVII-XVII cross-sectional line in FIG. 15. FIG. 18 is a side view of the state of FIG. 14 as seen from the lid member side.

[0121] The light emitting device 400 in this embodiment differs from the light emitting device 400 in the embodiments described so far in that a stepped substrate 1590 is used instead of the first substrate 15 and the second substrate 90 in the embodiments described so far. The light emitting device 400 further includes a cap 16 (hereinafter referred to as the first cap 16) that surrounds one or more light emitting elements 20 but does not surround the lens member 40, and a cap 96 (hereinafter referred to as the second cap 96) that surrounds the package 10, the lens member 40, and the light control unit 50. The light emitting device 400 further includes a lid member 91.

[0122] (Board 1590) The substrate 1590 has a first upper surface 15A and a second upper surface 90A. The first upper surface 15A is a surface on which the first mounting surface 11M is provided, and the second upper surface is a surface on which the second mounting surface 90M is provided. As already described in the other embodiments, one or more light-emitting elements 20 are arranged on the first mounting surface 11M, and the lens member 40 and the light control unit 50 are arranged on the second mounting surface 90M. The first upper surface 15A is provided above the second upper surface 90A.

[0123] In top view, the outer shape of the substrate 1590 is rectangular. This rectangle has short sides and long sides. In top view, the second top surface 90A is surrounded by the first top surface 15A. The first top surface 15A surrounds the second top surface 90A except for a portion. The portion not surrounded by the first top surface 15A includes a portion where the lid member 91 is provided. In the illustrated light-emitting device 400, the second top surface 90A is surrounded by the first top surface 15A except for the portion where the lid member 91 is provided. The portion where the lid member 91 is provided is provided on the opposite side of the second top surface 90A from the side where the light-emitting element 20 is arranged.

[0124] The portion where the cover member 91 is provided has a concave shape in side view. The upper surface of the concave shape is the first upper surface 15A, and the lower upper surface is the second upper surface 90A. The length of the second upper surface 90A in this concave shape is 1 / 2 or less of the length of the substrate 1590 in the same direction. The second upper surface 90A in this concave shape is provided in a position where an imaginary straight line passing through the center of the width of the substrate 1590 in a direction parallel to the second upper surface 90A and extending in a direction perpendicular to the second upper surface 90A does not pass through in side view. In simple terms, the concave shape is provided at a position closer to one side than the center of the side surface of the substrate 1590 that forms the concave shape.

[0125] In the substrate 1590, the multiple wiring regions 14 provided on the first mounting surface 11M can be electrically connected to wiring regions provided on the lower surface of the base 1590 through via holes passing through the inside of the substrate 1590.

[0126] Substrate 1590 can be formed from the same material as substrate 15 or substrate 90. For example, substrate 1590 can be formed from a ceramic as the main material. Substrate 1590 can be formed from a light-blocking material that blocks light. Substrate 1590 can be formed from a light-blocking ceramic as the main material.

[0127] (2nd Cap 96) The second cap 96 is bonded to the first upper surface 15A of the substrate 1590. The second cap 96 has a concave shape in a side view, and this concave shape is provided at a position corresponding to the concave shape of the substrate 1590. By bonding the substrate 1590 and the second cap 96, an opening defined by each concave shape is formed.

[0128] The second cap 96 can be made of a light-shielding material that blocks light. For example, the second cap 96 can be made by forming the shape of the second cap 96 out of glass and providing a light-shielding film on the surface.

[0129] (Cover member 91) The lid member 91 is translucent. The lid member 91 has a flat plate shape. The lid member 91 is joined to the substrate 1590 and the second cap 96. The lid member 91 covers an opening defined by the joining of the substrate 1590 and the second cap 96. By joining the lid member 91, the space in which the lens member 40 is disposed can be made a closed space.

[0130] (Light emitting device 400) Next, the light emitting device 400 will be described.

[0131] The space in which one or more light emitting elements 20 are disposed is sealed by the substrate 1590 and the first cap 16. This forms a package structure surrounding the light emitting element 20. Furthermore, the substrate 1590 and the second cap 96 surround a space in which the package structure surrounding one or more light emitting elements 20, the lens member 40, and the light control unit 50 are disposed. However, a lid member 91 is joined to the opening so that the light emitted from the light control unit 50 is emitted to the outside.

[0132] In a side view, the first optical axis 21a of the first light 22a, the second optical axis 21b of the second light 22b, and the third optical axis 21c of the third light 22c emitted from the light control unit 50 are included in the opening in which the cover member 91 is provided. In a side view, the main portions of each of the first light 22a, the second light 22b, and the third light 22c emitted from the light control unit 50 are included in the opening in which the cover member 91 is provided. The first light 22a, the second light 22b, and the third light 22c are emitted from the cover member 91.

[0133] In side view, the light emission point of the light-emitting element 20 arranged at the position farthest from the lid member 91 is not included in the opening in which the lid member 91 is provided. For example, the second light-emitting element 20b may be the light-emitting element 20 arranged at the position farthest from the lid member 91. This makes it possible to prevent light from leaking from unnecessary locations. Note that, in side view, the light emission point of the first light-emitting element 20a may also be arranged not to be included in the opening in which the lid member 91 is provided.

[0134] <Fifth embodiment> A light emitting device 500 according to the fifth embodiment will be described. Fig. 19 is a diagram for explaining an exemplary embodiment of the light emitting device 500. Fig. 19 is a cross-sectional view of the light emitting device 500. The cross-sectional position of the light emitting device 500 in this cross-sectional view corresponds to Fig. 17 of the fourth embodiment. Fig. 20 is a perspective view of a substrate 1590 provided in the light emitting device 500.

[0135] The light emitting device 500 differs from the substrate 1590 of the fourth embodiment in that the first mounting surface 11M and the peripheral region 11P are provided on different planes in the substrate 1590. In the substrate 1590 of the light emitting device 500, the upper surface on which the first mounting surface 11M is provided is lower than the upper surface on which the peripheral region 11P is provided. The upper surface on which the peripheral region 11P is provided is also the bonding surface to which the second cap 96 is bonded. Therefore, in order to be consistent with the fourth embodiment, the upper surface on which the peripheral region 11P is provided is referred to as the first upper surface 15A. In the substrate 1590 of the light emitting device 500, the upper surface on which the first mounting surface 11M is provided is referred to as the third upper surface 15B.

[0136] The third top surface 15B is surrounded by the first top surface 15A in a top view. The third top surface 15B is located 50 μm to 500 μm below the first top surface 15A. By providing the first top surface 15A above the third top surface 15B, the wiring region 14 can be extended to directly below the peripheral region 11P, and the size of the wiring region 14 exposed on the third top surface 15B can be reduced. This can contribute to the miniaturization of the light emitting device.

[0137] The length (thickness) in the vertical direction of the submount 30 is greater than the difference between the first upper surface 15A and the third upper surface 15B. The thickness of the submount 30 is greater than the difference between the first upper surface 15A and the third upper surface 15B by an amount in the range of 200 μm to 1000 μm. This makes it possible to raise the height of the light emitting point so that the main portion of the light emitted from the light emitting element 20 is not irradiated onto the first upper surface 15A.

[0138] <Head-mounted display> FIG. 21 is a side view showing a schematic configuration example of a head mounted display 600 including a light emitting device 100 (200, 300, 400, 500) according to an embodiment of the present disclosure. Hereinafter, the light emitting device 100 will be described as an example, but the head mounted display 600 may include any of the light emitting devices 200, 300, 400, and 500 instead of the light emitting device 100. This head mounted display 600 includes a temple 650 and a waveguide 660 connected to the temple 650. The waveguide 660 has a light emission region such as a diffraction grating. The laser light incident on the waveguide 660 can be emitted from the light emission region of the waveguide 660 toward the retina of the user's eye.

[0139] One end of the temple 650 is located on the waveguide 660 side, in other words, on the user's face side, and the other end of the temple 650 is located on the opposite side of the waveguide 660, in other words, on the user's ear side. In Fig. 21, both ends of the temple 650 are parallel to the direction of the optical axis of the lens member 40. Based on a user wearing the head mounted display 600, the direction of the optical axis of the lens member 40 is approximately parallel to the direction from the user's ear to the eye (or the opposite direction) in a side view.

[0140] In the example of the head mounted display 600 shown in Fig. 21, the light emitting device 100 is supported inside the temple 650. In Fig. 21, the light emitting device 100 is depicted as if it is seen from the side, but in reality, the appearance of the light emitting device 100 is not visible from the outside. The size of the light emitting device 100 in the direction parallel to the first direction S1 and the second direction S2 is, for example, 3 mm or more and 15 mm or less, which is smaller than the size in the extension direction of the temple 650 (direction 1D perpendicular to the first direction S1 and the second direction S2 in Fig. 21).

[0141] It is preferable that the light emitting device 100 is mounted on the head mounted display 600 so that the direction of the optical axis of the lens member in the light emitting device 100 is parallel to the direction in which the temple of the head mounted display 600 extends. The width of the temple 650 can be reduced by the light emitting device 100 that is miniaturized in the direction perpendicular to the optical axis of the lens member. As shown in the figure, the length of the temple 650 is a length that ensures the distance from the user's eyes to the ears, so that if the size of the optical axis direction of the lens member in the light emitting device 100 is small to a certain extent, even if it becomes smaller than that, it does not contribute to the miniaturization of the head mounted display 600.

[0142] In this embodiment, the light emitting device 100 may emit collimated beams of the first light, the second light, and the third light on a coaxial line from a narrow region. The first light, the second light, and the third light are laser beams of any of red, green, and blue colors, respectively. The laser beams of each color are scanned by a MEMS element such as a micromirror, travel through the waveguide 660, and eventually form an image on the user's retina. The display of a color image may be performed by a field sequential method. In that case, the first light, the second light, and the third light are emitted sequentially. In order to monitor the intensity of the first light, the second light, and the third light, a photodetector such as a photodiode may be used for each light. The photodetector may be disposed outside or inside the light emitting device 100. The photodetector may also be disposed inside the package 10 of the light emitting device 100.

[0143] In the case of a method for forming an image on the retina, it is preferable to make the focused spot of the beam on the retina as small as possible in order to achieve high resolution. From this viewpoint, it is preferable that the focal length of the lens member is long. On the other hand, if the focal length is long, the light spreads, and more light does not enter the lens surface of the lens member 40, which may result in increased light loss. In the case of laser light, the light spreads more in the fast axis direction than in the slow axis direction, so the fast axis direction is more susceptible to loss.

[0144] In addition, the shape of the laser light is larger in the slow axis direction than in the fast axis direction in the near-field pattern, so when collimated with a lens having the same focal length for the slow axis and the fast axis, the focused spot on the retina is larger in the slow axis direction.

[0145] Therefore, it is preferable to design the lens surface of the lens member 40 so that the focal length in the slow axis direction is longer than the focal length in the fast axis direction, thereby making it possible to reduce the size of the focused spot in the slow axis direction without increasing the loss of laser light.

[0146] Although the embodiments of the present invention have been described above, the light-emitting device of the present invention is not strictly limited to the light-emitting device of the embodiment. In other words, the present invention can be realized only if it is limited to the external shape and structure of the light-emitting device disclosed in the embodiment. For example, it may be a light-emitting device without a protective element. In addition, it can be applied without necessarily having all the components. For example, if some of the components of the light-emitting device disclosed in the embodiment are not described in the claims, the freedom of design by a person skilled in the art, such as substitution, omission, modification of the shape, and change of the material, is recognized for those some components, and the invention described in the claims is specified to be applied. [Industrial Applicability]

[0147] The light emitting device according to each embodiment can be used in head mounted displays, projectors, lighting, displays, and the like. [Explanation of symbols]

[0148] 10 packages 10A light extraction surface 11 Base 11M Mounting surface 11P Surrounding Area 12 Side wall 13 Translucent area 14 Wiring area 15 Substrate (first substrate) 16 Cap 17 Metal layer 20 Light emitting element 20a First light emitting element 20b Second light-emitting element 20c Third light-emitting element 30 Submount 40 Lens parts 50 Optical Control Unit 51 First area 52 Second area 53 Third area 54 4th area 55a First optical member 55b First optical member 56 Second optical member 57 Third optical member 60A protection element 60B Temperature measuring element 70 Wiring 90 Board (Second Board) 100 Light emitting device (first embodiment) 200 Light emitting device (second embodiment) 300 Light emitting device (third embodiment) 400 Light emitting device (fourth embodiment) 500 Light emitting device (fifth embodiment) 600 Head Mounted Display

Claims

1. a first light emitting element having a first light emitting surface that emits a first light along a first optical axis; a second light-emitting element having a second light-emitting surface that is disposed at a position where a virtual plane that is parallel to the first light-emitting surface and passes through the first light-emitting element passes, and that is spaced apart from the first light-emitting element in a first direction perpendicular to the first optical axis, and that emits a second light along a second optical axis that is inclined relatively from the first optical axis in a second direction opposite to the first direction; a third light emitting element having a third light emitting surface that is disposed at a position through which the virtual plane passes and that is spaced apart from the first light emitting element in the second direction, and that emits a third light along a third optical axis that is inclined relatively from the first optical axis in the first direction; Equipped with a lens member having an incident surface onto which the first light, the second light, and the third light emitted from the first light-emitting element, the second light-emitting element, and the third light-emitting element are incident, on the entrance surface of the lens member, a first entrance point into which the first light traveling along the first optical axis is incident, a second entrance point into which the second light traveling along the second optical axis is incident, and a third entrance point into which the third light traveling along the third optical axis is incident are closer to each other than a first exit point from which the first light traveling along the first optical axis is emitted on the first light exit surface, a second exit point from which the second light traveling along the second optical axis is emitted on the second light exit surface, and a third exit point from which the third light traveling along the third optical axis is emitted on the third light exit surface, a first light beam, a second light beam, and a third light beam, each of which is a diverging light beam at a position where the first light beam, the second light beam, and the third light beam are incident on the incident surface of the lens member;

2. A first light-emitting element having a first light-emitting surface that emits a first light along a first optical axis; a second light-emitting element having a second light-emitting surface that is disposed at a position where a virtual plane that is parallel to the first light-emitting surface and passes through the first light-emitting element passes, and that is spaced apart from the first light-emitting element in a first direction perpendicular to the first optical axis, and that emits a second light along a second optical axis that is inclined relatively from the first optical axis in a second direction opposite to the first direction; a third light emitting element having a third light emitting surface that is disposed at a position through which the virtual plane passes and that is spaced apart from the first light emitting element in the second direction, and that emits a third light along a third optical axis that is inclined relatively from the first optical axis in the first direction; Equipped with a lens member having an incident surface onto which the first light, the second light, and the third light emitted from the first light-emitting element, the second light-emitting element, and the third light-emitting element are incident, the lens member is a collimating lens, on the entrance surface of the lens member, a first entrance point into which the first light traveling along the first optical axis is incident, a second entrance point into which the second light traveling along the second optical axis is incident, and a third entrance point into which the third light traveling along the third optical axis is incident are closer to each other than a first exit point from which the first light traveling along the first optical axis is emitted on the first light exit surface, a second exit point from which the second light traveling along the second optical axis is emitted on the second light exit surface, and a third exit point from which the third light traveling along the third optical axis is emitted on the third light exit surface, When viewed from above, an end of the lens member in the first direction is located closer to the first direction than an end of the second light emitting surface of the second light emitting element in the first direction, a light emitting device, wherein, in the top view, an end of the lens member in the second direction is located on the second direction side of an end of the third light emitting surface of the third light emitting element in the second direction.

3. The light emitting device according to claim 1 , wherein the lens member has one lens surface through which the first light, the second light, and the third light exit.

4. The inclination of the second optical axis from the first optical axis is in a range of more than 0 degrees and not more than 30 degrees, The light emitting device according to claim 1 , wherein an inclination of the third optical axis from the first optical axis is in a range of more than 0 degrees and not more than 30 degrees.

5. 4. The light emitting device according to claim 1, wherein a difference between an absolute value of a tilt of the second optical axis from the first optical axis and an absolute value of a tilt of the third optical axis from the first optical axis is in a range of 0 degrees or more and 5 degrees or less.

6. 5. The light emitting device according to claim 4, wherein a difference between an absolute value of a tilt of the second optical axis from the first optical axis and an absolute value of a tilt of the third optical axis from the first optical axis is in a range of 0 degrees or more and 5 degrees or less.

7. A first light-emitting element having a first light-emitting surface that emits a first light along a first optical axis; a second light-emitting element having a second light-emitting surface that is disposed at a position where a virtual plane that is parallel to the first light-emitting surface and passes through the first light-emitting element passes, and that is spaced apart from the first light-emitting element in a first direction perpendicular to the first optical axis, and that emits a second light along a second optical axis that is inclined relatively from the first optical axis in a second direction opposite to the first direction; a third light emitting element having a third light emitting surface that is disposed at a position through which the virtual plane passes and that is spaced apart from the first light emitting element in the second direction, and that emits a third light along a third optical axis that is inclined relatively from the first optical axis in the first direction; Equipped with a lens member having an incident surface onto which the first light, the second light, and the third light emitted from the first light-emitting element, the second light-emitting element, and the third light-emitting element are incident, on the entrance surface of the lens member, a first entrance point into which the first light traveling along the first optical axis is incident, a second entrance point into which the second light traveling along the second optical axis is incident, and a third entrance point into which the third light traveling along the third optical axis is incident are closer to each other than a first exit point from which the first light traveling along the first optical axis is emitted on the first light exit surface, a second exit point from which the second light traveling along the second optical axis is emitted on the second light exit surface, and a third exit point from which the third light traveling along the third optical axis is emitted on the third light exit surface, a light control unit which receives the first light, the second light, and the third light which have passed through the lens member and emits the first light, the second light, and the third light, the first optical axis, the second optical axis, and the third optical axis of which are parallel to each other; the second light traveling along the second optical axis is incident on the light control unit at a position spaced apart from the first optical axis in the second direction; A light emitting device, wherein a third light beam traveling along the third optical axis is incident on the light control unit at a position spaced apart from the first optical axis in the first direction.

8. The light emitting device according to claim 1 , further comprising a submount on which the first light emitting element, the second light emitting element, and the third light emitting element are mounted.

9. the submount has a side surface intersecting a top surface; the first light-emitting element, the second light-emitting element, and the third light-emitting element are arranged such that a first emission point from which the first light traveling along the first optical axis on the first light-emitting surface is emitted, a second emission point from which the second light traveling along the second optical axis on the second light-emitting surface is emitted, and a third emission point from which the third light traveling along the third optical axis on the third light-emitting surface is emitted protrude from an outer edge located at a boundary between the top surface and the side surface of the submount; The light emitting device according to claim 8 , wherein the first optical axis direction intersects with a direction in which the outer edge extends at an angle other than 90° when viewed from above.

10. 10. The light emitting device of claim 9, wherein the top surface of the submount is a parallelogram with a non-90 degree apex angle.

11. The light emitting device according to claim 1 , wherein the first light emitting element, the second light emitting element, and the third light emitting element are semiconductor laser elements.

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