Light-emitting device

Abstract

To provide a compact light-emitting device.SOLUTION: A light-emitting device 100 includes: a first light-emitting element 10 that includes a first light-emitting surface 11 from which first emission light of a first emission color is emitted; a wavelength conversion member 40 that receives light of the first emission color to convert a wavelength of the light and emits wavelength-converted light; a second light-emitting element 20 that includes a second light-emitting surface 21 from which second emission light of a second emission color is emitted; and an optical member 30 that includes an optical action layer 37 having different reflectance and transmittance in accordance with a wavelength of light. In the optical action layer 37, the first emission light is reflected without being transmitted. The wavelength conversion member 40 receives the first emission light reflected by the optical action layer 37 to emit the wavelength-converted light. In the optical action layer 37, the wavelength-converted light is transmitted and the second emission light is reflected without being transmitted. The wavelength-converted light and the second emission light are emitted from an upward-facing surface of the optical action layer.SELECTED DRAWING: Figure 1

Description

Technical Field

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

Background Art

[0002] Semiconductor light-emitting elements such as semiconductor lasers (LDs) and light-emitting diodes (LEDs) are used as in-vehicle headlights and lighting light sources. For example, Patent Document 1 discloses a light-emitting device including a semiconductor laser, a reflecting member, and a phosphor, which emits a mixed-color light of light from the semiconductor laser element and fluorescence from the phosphor. Also, a light-emitting device in which a light-emitting unit including a semiconductor laser, a reflecting member, and a phosphor is disposed opposite to each other is disclosed.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] One object of the present disclosure is to provide a compact light-emitting device.

Means for Solving the Problems

[0005] <00A light-emitting device according to one embodiment of the present invention comprises a first light-emitting element having a first light-emitting surface that emits first emitted light of a first emission color, a wavelength-converting member that emits wavelength-converted light obtained by receiving the light of the first emission color and performing wavelength conversion, a second light-emitting element having a second light-emitting surface that emits second emitted light of a second emission color, an optical member having an optical working layer with different reflectance and transmittance depending on the wavelength of light, and a light extraction surface, wherein in the optical working layer, the first emitted light is reflected without being transmitted, the wavelength-converted member emits the wavelength-converted light upon receiving the first emitted light reflected by the optical working layer, the wavelength-converted light is transmitted in the optical working layer and the second emitted light is reflected without being transmitted, and the wavelength-converted light and the second emitted light are emitted from the light extraction surface. [Effects of the Invention]

[0006] According to the above-described light-emitting device, the light-emitting element is divided into a first light-emitting element for wavelength conversion light and a second light-emitting element for second emitted light, and the light emitted from these light-emitting elements is controlled by a single optical component, thus providing a compact light-emitting device. [Brief explanation of the drawing]

[0007] [Figure 1] This is a schematic cross-sectional view showing a light-emitting device according to Embodiment 1 of the present invention. [Figure 2] Figure 1 is a block diagram of the light-emitting device. [Figure 3] Figure 1 is a schematic cross-sectional view of the optical component. [Figure 4] Figure 1 is a schematic cross-sectional view of the optical component. [Figure 5] Figure 1 is a plan view of the light-emitting device. [Figure 6] This is a plan view showing a light-emitting device according to Embodiment 2 of the present invention. [Figure 7] This is a plan view showing a light-emitting device according to Embodiment 3 of the present invention. [Figure 8] This is a plan view showing a light-emitting device according to Embodiment 4 of the present invention. [Modes for carrying out the invention]

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

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

[0010] Furthermore, in this specification or the claims, descriptions such as up and down (up / down), left and right, front and back, front and back (front / back), and front and back merely describe relative positions, orientations, and directions, and do not necessarily correspond to the relationships during use.

[0011] Furthermore, in this specification or the claims, when there are multiple components and each is to be expressed separately, the components may be distinguished by adding "1st," "2nd," etc., to their names. Also, the objects being distinguished may differ between this specification and the claims. Therefore, even if a component with the same prefix as in this specification is described in the claims, the objects identified by this component may not be the same in this specification and the claims.

[0012] For example, if there are components in this disclosure that are distinguished by being labeled "1st," "2nd," and "3rd," and the components labeled "1st" and "3rd" in this disclosure are described in the claims, then for readability, the components may be distinguished in the claims by being labeled "1st" and "2nd." In this case, the components labeled "1st" and "2nd" in the claims refer to the components labeled "1st" and "3rd" in this disclosure, respectively. This rule is not limited to components, but can be applied to other subjects in a reasonable and flexible manner.

[0013] The following describes embodiments for carrying out the present invention. Furthermore, specific embodiments for carrying out the present invention will be described with reference to the drawings. However, the embodiments for carrying out the present invention are not limited to these specific embodiments. In other words, the illustrated embodiments are not the only forms in which the present invention is realized. Note that the size and positional relationships of the components shown in each drawing may be exaggerated for the sake of ease of understanding. [Embodiment 1]

[0014] Figure 1 shows a schematic cross-sectional view of the light-emitting device according to Embodiment 1. The light-emitting device 100 shown in this figure comprises a first light-emitting element 10, a wavelength conversion member 40, a second light-emitting element 20, and an optical element 30. These first light-emitting element 10, wavelength conversion member 40, second light-emitting element 20, and optical element 30 are housed in a package 50. (Package 50)

[0015] The package 50 includes a base portion 52 and a lid portion 51. The base portion 52 is formed in a box shape with an open top surface. Further, in the base portion 52, a cavity for accommodating one or more components included in the light-emitting device 100, such as the first light-emitting element 10, is formed. The base portion 52 is preferably formed using a material such as ceramics or metal with excellent heat dissipation properties. Also, the open end of the top surface of the base portion 52 is closed by the lid portion 51. The lid portion 51 is made of a translucent member such as sapphire or glass. Here, the base portion 52 is sealed by the lid portion 51. The package 50 is constituted by joining the base portion 52 and the lid portion 51. The closed space formed inside the package 50 is a sealed space. Further, this internal space is a sealed space that is airtight in a predetermined atmosphere.

[0016] The base portion 52 has a top surface and a bottom surface. The outer shape of the base portion 52 is rectangular in a top view. This rectangle may be a rectangle having a long side and a short side. Note that the outer shape of the base portion 52 in a top view does not have to be rectangular. Unless there is a mention excluding a square, the rectangle may include a square.

[0017] The base portion 52 has a mounting surface. For example, the top surface of the base portion 52 can be the mounting surface. Other components are mounted on the mounting surface.

[0018] The lid portion 51 has a top surface and a bottom surface. The bottom surface of the lid portion 51 faces the top surface of the base portion 52. The lid portion 51 transmits light of a predetermined wavelength. The lid portion 51 has translucency from the bottom surface to the top surface. Here, having translucency with respect to light of a predetermined wavelength means that the transmittance with respect to light of a predetermined wavelength is 80% or more.

[0019] The base portion 52 is composed of a mounting substrate 53 and a frame member 54. The top surface of the mounting substrate 53 forms the bottom surface of the cavity of the base portion 52. The first light-emitting element 10, the optical member 30 to which the wavelength conversion member 40 is joined, and the second light-emitting element 20 are mounted on the top surface of the mounting substrate 53. The top surface of the mounting substrate 53 functions as a mounting surface. Also, the frame member 54 constitutes the peripheral wall of the cavity.

[0020] The main material of the mounting substrate 53 is metal or a composite material containing metal. For example, the main material of the mounting substrate 53 is copper. The main material of the frame member 54 is ceramics. For example, the main material of the frame member 54 is aluminum nitride, silicon nitride, or aluminum oxide. The main material of the lid 51 is, for example, quartz, silicon carbide, sapphire, or glass.

[0021] Here, the main material refers to the material that accounts for the largest proportion by weight or volume in the object being considered. If the object is formed from a single material, that material is the main material. In other words, for a material to be the main material includes the possibility of that material accounting for 100% of the total material.

[0022] The base 52 may be formed integrally from the same material as the mounting substrate 53 and the frame member 54. Using metal for the mounting substrate 53 results in a base 52 with excellent heat dissipation, but the base is not limited to this type. (First light-emitting element 10)

[0023] The first light-emitting element 10 has a first light-emitting surface 11 that emits light of a first emission color (hereinafter referred to as the first emitted light). The light of the first emission color is the light that excites the wavelength conversion member 40. The first light-emitting element 10 is, so to speak, an excitation light source that excites the wavelength conversion member 40. Such a first light-emitting element 10 can be a semiconductor light-emitting element such as a semiconductor laser (LD) or a light-emitting diode (LED). For example, the semiconductor light-emitting element can be configured as a CoS (Chip on Submount) pre-mounted on a submount 15, and this can be mounted on the mounting surface of the package 50.

[0024] The wavelength conversion member 40 receives the first emitted light from the first light-emitting element 10 and emits light of a third emission color (hereinafter referred to as wavelength-converted light) that has been converted to a wavelength different from that of the first emitted light. Such a wavelength conversion member 40 can suitably use phosphors or the like (details will be described later). (Second light-emitting element 20)

[0025] The second light-emitting element 20 emits a second emitted light of a second color. This second light-emitting element 20 has a second light-emitting surface 21 from which the second emitted light is emitted. The second emitted light is emitted to the outside without wavelength conversion by the wavelength conversion member 40. At this time, light is emitted which is a mixture of the second emitted light and the wavelength-converted light. Such a second light-emitting element 20 can suitably utilize semiconductor light-emitting elements such as semiconductor lasers (LDs) and light-emitting diodes (LEDs). Preferably, the semiconductor light-emitting elements constituting the second light-emitting element 20 are made of CoS pre-mounted on the submount 15 and mounted on the package 50 simultaneously with the first light-emitting element 10. In this case, in order to prevent degradation due to heat, it is preferable to mount the CoS after mounting the optical member 30 on the package 50.

[0026] It is preferable that the first emission color of the first light-emitting element 10 and the second emission color of the second light-emitting element 20 be from the same color family. Using the same color family makes it easier to manufacture the optical component 30 because it reduces the complexity of the optical design of the optical working layer 37. An example of an uncomplex optical design is one in which it is sufficient to separate the wavelength range to be transmitted from the wavelength range to be reflected at a specific wavelength boundary, and it is not necessary to create a boundary at another specific wavelength. For example, both the first and second emission colors can be blue. Furthermore, by making the third emission color yellow, white light can be obtained by mixing the colors, which can be used for applications such as lighting and headlights.

[0027] Furthermore, it is preferable that the difference between the main emission peak wavelength of the first light-emitting element 10 and the main emission peak wavelength of the second light-emitting element 20 be 20 nm or less. Hereafter, when the first light-emitting element 10 and the second light-emitting element 20 are described together, they will be referred to as "light-emitting elements."

[0028] The light emitted from the light-emitting element does not have to be blue. The mixed-color light emitted from the light-emitting device 100 does not have to be white. For example, a light-emitting element that emits green light or a light-emitting element that emits red light may be used. In addition, a light-emitting element that emits light of other colors may be used.

[0029] Here, blue light is defined as light whose emission peak wavelength is in the range of 420 nm to 494 nm. Green light is defined as light whose emission peak wavelength is in the range of 495 nm to 570 nm. Red light is defined as light whose emission peak wavelength is in the range of 605 nm to 750 nm. For example, a light-emitting element emits light whose emission peak wavelength is in the range of 430 nm to 480 nm.

[0030] Here, we will describe a semiconductor laser element, which is an example of a light-emitting element. When viewed from above, a semiconductor laser element has a rectangular shape with one opposite side being the longer side and the other opposite side being the shorter side. The light (laser beam) emitted from the semiconductor laser element has a broadened shape. In addition, divergent light is emitted from the emission end face of the semiconductor laser element. The emission end face of the semiconductor laser element can be called the light emission surface of the light-emitting element.

[0031] Light emitted from a semiconductor laser element forms an elliptical far-field pattern (hereinafter referred to as "FFP") on a plane parallel to the light emission end face. FFP refers to the shape and light intensity distribution of the emitted light at a position away from the emission end face.

[0032] Here, the light passing through the center of the elliptical shape of the FFP, in other words, the light with the peak intensity in the FFP's light intensity distribution, is referred to as the light traveling along the optical axis, or the light passing through the optical axis. Furthermore, in the FFP's light intensity distribution, the peak intensity value is 1 / e 2 Light with the above intensity will be referred to as the main part of the light.

[0033] The shape of the fast-flow plane (FFP) of light emitted from a semiconductor laser element is an ellipse, with the length in the stacking direction being longer than the length in the direction perpendicular to the stacking direction, on a plane parallel to the light emission end face. The stacking direction refers to the direction in which multiple semiconductor layers, including the active layer, are stacked in the semiconductor laser element. The direction perpendicular to the stacking direction can also be called the plane direction of the semiconductor layer. Furthermore, the major axis direction of the elliptical shape of the FFP can be called the speed axis direction of the semiconductor laser element, and the minor axis direction can be called the slow axis direction of the semiconductor laser element.

[0034] Based on the light intensity distribution of FFP, 1 / e of the peak light intensity 2 The angle at which light of a given light intensity spreads is defined as the divergence angle of the semiconductor laser element. The divergence angle is 1 / e of the peak light intensity. 2 In addition to the light intensity, it can also be determined from, for example, the light intensity at half the peak light intensity. In this specification, when we simply refer to the "angle of divergence," we mean 1 / e of the peak light intensity. 2 This refers to the angle of light divergence at a given light intensity. It should be noted that the angle of divergence in the fast axis direction is greater than the angle of divergence in the slow axis direction.

[0035] For example, a semiconductor laser element with a divergence angle in the slow axis direction ranging from 2 to 30 degrees can be used as the light-emitting element. For example, a semiconductor laser element with a divergence angle in the fast axis direction ranging from 5 to 120 degrees can be used as the light-emitting element.

[0036] Examples of semiconductor laser elements that emit blue light or green light include semiconductor laser elements containing nitride semiconductors. Examples of nitride semiconductors that can be used include GaN, InGaN, and AlGaN. Examples of semiconductor laser elements that emit red light include those containing InAlGaP, GaInP, GaAs, and AlGaAs semiconductors. (Submount 15)

[0037] The submount 15 on which the light-emitting element is mounted has a top surface and a bottom surface. The submount 15 is configured in the shape of a rectangular parallelepiped. When viewed from above, the submount 15 has a rectangular outline with long sides and short sides. The submount 15 has the smallest width in the vertical direction. The vertical width of the submount 15 can be between 50 μm and 1000 μm. Note that the shape of the submount 15 is not limited to a rectangular parallelepiped. The submount 15 can be formed using, for example, silicon nitride, aluminum nitride, or silicon carbide. In addition, a metal film for bonding is provided on the bonding surface. (Optical component 30)

[0038] The optical element 30 is a wavelength-selective reflector that selectively reflects light according to wavelength. The optical element 30 has an optical working layer 37 inside. The optical working layer 37 has different reflectance and transmittance depending on the wavelength of light. This optical working layer 37 is positioned diagonally inside the optical element so that it faces the first light-emitting surface 11 of the first light-emitting element 10 and the wavelength conversion member 40.

[0039] The optical member 30 is formed in the shape of a box. As shown in Figure 1, the box-shaped optical member 30 has a first surface 31, a second surface 32 opposite to the first surface 31, a third surface 33, and a fourth surface 34 opposite to the third surface 33 in a cross-sectional view. In the figure, the bottom surface of the optical member 30 corresponds to the first surface 31, the top surface to the second surface 32, the left surface to the third surface 33, and the right surface to the fourth surface 34. A wavelength conversion member 40 is positioned below the first surface 31. The first surface 31 of the optical member 30 is joined to the wavelength conversion member 40. The joining of the wavelength conversion member 40 and the first surface 31 of the optical member 30 may be done using an adhesive, or it may be done directly without using an adhesive. For example, a reflective phosphor, which is one form of the wavelength conversion member 40, may be joined to the first surface 31 of a dichroic mirror, which is one form of the optical member 30, using SAB (interface activated bonding) or ADB (atomic diffusion bonding). In this way, the optical component 30, which integrates the wavelength conversion component 40, is mounted on the package 50.

[0040] The third surface 33 faces the first light-emitting surface 11 of the first light-emitting element 10. The first emitted light emitted from the first light-emitting element 10 is incident on the third surface 33. The fourth surface 34 faces the second light-emitting surface 21 of the second light-emitting element 20. The second emitted light emitted from the second light-emitting element 20 is incident on the fourth surface 34. Thus, in Figure 1, the first light-emitting element 10 and the second light-emitting element 20 are arranged so that their first light-emitting surface 11 and second light-emitting surface 21 face each other with the optical member 30 in between. (Optical action layer 37)

[0041] The optical working layer 37 is a part of the optical member 30. The optical working layer 37 is positioned diagonally with respect to the mounting surface. The optical working layer 37 may constitute the entirety of the optical member 30. Inside the optical member 30, the optical working layer 37 is positioned diagonally so as to face the first surface 31 and the third surface 33. The optical working layer 37 is also positioned diagonally so as to face the second surface 32 and the fourth surface 34 inside the optical member 30. Of the optical working layer 37, the surface facing the first surface 31 and the third surface 33 of the optical member 30 is called the first optical working surface 38 (lower left surface in Figure 1), and the surface on its back side, facing the second surface 32 and the fourth surface 34 of the optical member 30, is called the second optical working surface 39 (upper right surface in Figure 1).

[0042] Preferably, within the optical element, the optical working layer 37 is tilted at an angle of 45° with respect to the first surface 31 (the horizontal plane in Figure 1) from the point of contact between the first surface 31 and the fourth surface 34. As a result, the first optical working surface 38 of the optical working layer 37 faces both the first light-emitting element 10 and the wavelength conversion member 40, and the first emitted light incident on the optical element 30 from the third surface 33 is reflected toward the wavelength conversion member 40 located on the first surface 31 on the first optical working surface 38 side. Here, in the optical working layer 37, the first emitted light is reflected without being transmitted. Alternatively, the optical working layer 37 reflects at least 90% or more of the first emitted light. Alternatively, the optical working layer 37 reflects at least 95% or more of the first emitted light. Alternatively, the optical working layer 37 reflects at least 99% or more of the first emitted light.

[0043] In this disclosure, "reflected without transmission" can be understood as referring to a state in which it is desirable to reflect as much light as possible. Specifically, it refers to a configuration or structure in which it is desirable for the optical working layer 37 to have a reflectivity of 100% in order to maximize the emission efficiency of the light emitted from the light-emitting device 100, or, even if it is unclear whether such a configuration or structure exists, the optical working layer 37 is provided under a configuration or structure in which, even if the goal is to reflect as much light as possible, the purpose of other components is not lost. In cases that fit this interpretation, the specific reflectivity value is not that important; for example, a reflectivity of 80% does not mean that it does not qualify as "reflected without transmission."

[0044] The optical working layer 37 can be formed on the inner surface of the optical member 30, preferably in the form of a plate having a flat and smooth surface. For example, the optical member 30 can be formed by depositing a dielectric multilayer film on a beveled surface (main surface) of a transparent body of the optical member 30, which is made of a transparent material such as glass or plastic that transmits visible light, using a thin film deposition technique such as sputtering. Such an optical member 30 can be composed of, for example, a dichroic mirror or a prism. (Wavelength conversion member 40)

[0045] The wavelength conversion member 40 receives the first emitted light reflected by the optical working layer 37 and emits wavelength-converted light of a third emitted color obtained by wavelength-converting the first emitted color. Furthermore, the wavelength-converted light is transmitted through the optical working layer 37. The wavelength-converted light is incident on the optical working layer 37 from the downward-facing surface, passes through the optical working layer 37, and is emitted from the upward-facing surface of the optical working layer 37. The wavelength-converted light and the second emitted light are emitted from the upward-facing surface of the optical working layer 37. For example, the optical working layer 37 transmits 80% or more of the wavelength-converted light. It is also preferable that the wavelength-converted light is transmitted through the optical working layer 37 without being reflected. Note that "transmitted without being reflected" should be understood as the above explanation of "reflected without being transmitted" with "transmitted" and "transmitted" with "reflected".

[0046] The wavelength conversion component 40 may contain a phosphor. Examples of phosphors include cerium-activated yttrium aluminum garnet (YAG), cerium-activated lutetium aluminum garnet (LAG), europium-activated silicate ((Sr,Ba)2SiO4), α-sialon phosphor, β-sialon phosphor, etc. Among these, YAG phosphor has good heat resistance and is widely used when emitting white light by color mixing.

[0047] The optical element 30 has a light extraction surface from which wavelength-converted light and second emitted light are emitted. The second surface 32 of the optical element 30 is the light extraction surface. The second surface 32 is positioned opposite the lid 51. The wavelength-converted light that has passed through the optical working layer 37 from the wavelength-converting member 40 is emitted to the outside from the second surface 32. On the other hand, the optical working layer 37 reflects the second emitted light that has been incident on the optical element 30 from the fourth surface 34 toward the second surface 32 on the second optical working surface 39 side. Here again, the optical working layer 37 reflects the second emitted light without transmitting it. By reflecting the second emitted light directly toward the light extraction surface in this way, it is not necessary to allocate a portion of the second emitted light to the excitation light of the wavelength-converting member 40, and the second emitted light can be used as the emitted light of the light-emitting device 100 without loss.

[0048] The light emitted from the light extraction surface is observed as a mixed light of the second emitted light of the second emission color and the wavelength-converted light of the third emission color. For example, by selecting blue light as the first and second emission colors and yellow light as the third emission color, a light-emitting device that emits white light as a mixed light of these can be realized. In this way, by dividing the light-emitting element that serves as the light source of the light-emitting device into a first light-emitting element 10 for wavelength-converted light and a second light-emitting element 20 for the second emitted light, the advantage of easier color adjustment is obtained. (Drive unit 60)

[0049] Furthermore, as shown in the block diagram of Figure 2, the light-emitting device 100 is equipped with a drive unit 60 that can independently drive the first light-emitting element 10 and the second light-emitting element 20 to light up. The drive unit 60 can independently control the first drive current and the second drive current that drive the first light-emitting element 10 and the second light-emitting element 20, respectively. For example, in the example described above where the first and second light-emitting colors are blue light and the third light-emitting color is yellow light, the balance of light intensity between the blue light and the yellow light can be changed by increasing or decreasing the output of the first light-emitting element 10 and the second light-emitting element 20, respectively, making it easier to adjust the chromaticity.

[0050] Furthermore, a roughened area may be provided on the second surface 32, which is the light extraction surface of the optical element 30. The second emitted light is then configured to pass through the roughened area and be emitted from the second surface 32. This allows the output light to be diffused on the emission surface side of the optical element 30.

[0051] Furthermore, as shown in the cross-sectional view of Figure 3, it is preferable that the upper end of the optical working layer 37 of the optical member 30 does not intersect with the second surface 32, but intersects with the third surface 33 below the upper end of the third surface 33. This allows the optical path length of the optical member 30 to be increased, thereby widening the spot diameter of the output light and enabling it to be emitted.

[0052] Furthermore, it is preferable that the optical working layer 37 of the optical component 30 reflects light in the blue light wavelength range and transmits light in the wavelength range longer than this blue light wavelength range. Specifically, it is preferable that the optical working layer 37 reflects light in the wavelength range of at least 430 nm to 480 nm and transmits light in the wavelength range of at least 500 nm or longer. (reflective transmissive film 70)

[0053] Furthermore, it is preferable that the optical component 30 includes a reflective-transmitting film 70. The reflective-transmitting film 70 transmits the first and second emitted light while reflecting the wavelength-converted light, thus possessing wavelength selectivity. In this way, the reflective-transmitting film 70 has optical properties opposite to those of the optical working layer 37.

[0054] In the example shown in the cross-sectional view of Figure 3, the reflective transmissive film 70 is provided on the third surface 33 and the fourth surface 34 of the optical member 30. The first reflective transmissive film 71 provided on the third surface 33 transmits the first emitted light. The first reflective transmissive film 71 also reflects the wavelength-converted light. On the other hand, the second reflective transmissive film 72 provided on the fourth surface 34 transmits the second emitted light. The second reflective transmissive film 72 also reflects the wavelength-converted light that has passed through the optical working layer 37. Such first reflective transmissive film 71 and second reflective transmissive film 72 can be made of dielectric multilayer films (DBRs) or the like. (reflective film 80)

[0055] Furthermore, the optical member 30 may have a reflective film 80 on a part of its side surface. This allows for effective utilization of the light incident on the optical member 30. In the example shown in the plan view of Figure 5, the optical member 30 has a fifth surface 35 (lower side in the figure) that intersects with the first surface 31, second surface 32, third surface 33, and fourth surface 34, and a sixth surface 36 (upper side in the figure) that intersects with the first surface 31, second surface 32, third surface 33, and fourth surface 34 and faces the fifth surface 35. A first reflective film 81 is provided on the fifth surface 35. A second reflective film 82 is provided on the sixth surface 36. These first reflective films 81 and second reflective films 82 reflect the first emitted light, the second emitted light, and the wavelength-converted light. Such first reflective films 81 and second reflective films 82 can be made of a reflective material that does not have wavelength selectivity, such as a metal film. [Embodiment 2]

[0056] In the example shown in Figure 5, one first light-emitting element 10, one optical element 30 with a wavelength conversion member 40 joined to it, and one second light-emitting element 20 are arranged in a straight line within a single package. However, the present invention is not limited to this configuration, and multiple units of each element may be arranged. For example, the light-emitting device 200 according to Embodiment 2 shown in the plan view of Figure 6 shows an example in which two sets of sets, each consisting of a first light-emitting element 10, an optical element 30 with a wavelength conversion member 40 joined to it, and a second light-emitting element 20 arranged in a straight line, are arranged in parallel. In this figure, the same reference numerals are used for the same elements as in Embodiment 1 described above, and detailed explanations are omitted. By using multiple first light-emitting elements 10A, 10B, optical elements 30A, 30B with a wavelength conversion member 40 joined to it, and second light-emitting elements 20A, 20B in this way, the amount of light can be increased. Furthermore, the emitted color of the output light mixed by each set consisting of the first light-emitting elements 10A, 10B, optical elements 30A, 30B with a wavelength conversion member joined to it, and second light-emitting elements 20A, 20B may be the same, or different emitted colors may be used for each set. This makes it possible to configure a light-emitting device that can switch the lighting for each group, resulting in different colors of light.

[0057] Furthermore, in examples where multiple components are combined, the number of first light-emitting elements, the optical component to which the wavelength conversion component is joined, and the second light-emitting elements used does not need to be equal; any number may be used. For example, depending on the conversion efficiency of the wavelength conversion component, the number of first light-emitting elements used for excitation can be increased compared to the number of second light-emitting elements. [Embodiment 3]

[0058] As an example, in the light-emitting device 300 according to Embodiment 3 shown in the plan view of Figure 7, two first light-emitting elements 10A and 10B are arranged in parallel, and the optical element 30C to which the wavelength conversion member is joined is enlarged to cover the first emission surfaces of these two first light-emitting elements 10A and 10B, while the second light-emitting element 20 is the same size as in Embodiment 1, etc. In this figure as well, the same reference numerals are used for the same components as in Embodiment 1, etc. described above, and detailed explanations are omitted. For example, when using a YAG phosphor with a large red component as the wavelength conversion member 40, the conversion efficiency of the phosphor is low, so the number of first light-emitting elements is increased to increase the amount of first emission light for excitation. Similarly, when using a short-wave YAG phosphor with a small red component, a DBR is installed on the emission side to cut the short-wave component of the phosphor to adjust the color tone, so the total output of the phosphor is low, and therefore the number of first light-emitting elements 10 for excitation is increased. [Embodiment 4]

[0059] Conversely, the number of second light-emitting elements 20 can be increased compared to the number of first light-emitting elements 10. An example of this is shown in the plan view of Figure 8 as a light-emitting device 400 according to Embodiment 4. In this figure as well, the same reference numerals are used for the same components as in Embodiment 1 and the like described above, and detailed explanations are omitted. In the light-emitting device 400 according to Embodiment 4 in Figure 8, the first light-emitting elements 10 consist of two first light-emitting elements 10A and 10B arranged in parallel, similar to Figure 7, while the second light-emitting elements 20 consist of three second light-emitting elements 20A, 20B, and 20C arranged in parallel. The optical member 30D to which the wavelength conversion member 40 is joined is enlarged to cover the second emission surfaces of these three second light-emitting elements 20 or larger. For example, in cases where a light-emitting device with a strong blue component is required, such as for automotive headlights, the color can be adjusted by increasing the number of second light-emitting elements. In this way, the number of first and second light-emitting elements can be designed according to the required color tone, output, etc. In addition to changing the number of first and second light-emitting elements, the output of the first and second light-emitting elements may also be varied. For example, higher output can be achieved by using light-emitting elements with a higher rated current. Furthermore, the first and second light-emitting elements used may have the same rating, or they may have different ratings. However, it is preferable to use multiple light-emitting elements with the same rating, as this simplifies the control of the drive unit 60.

[0060] The present invention can also be implemented in the following embodiments.

[0061] [Section 1] A first light-emitting element having a first light-emitting surface that emits first emitted light of a first emission color, A wavelength conversion member that emits wavelength-converted light obtained by wavelength conversion upon receiving the light of the first emission color, A second light-emitting element having a second light-emitting surface that emits a second emitted light of a second emission color, An optical component having an optical working layer with different reflectance and transmittance depending on the wavelength of light, A light-emitting device comprising, In the optical working layer, the first emitted light is reflected without being transmitted. The wavelength conversion member receives the first emitted light reflected by the optical working layer and emits the wavelength converted light. In the optical working layer, the wavelength-converted light is transmitted, and the second emitted light is reflected without being transmitted. A light-emitting device from which the wavelength-converted light and the second emitted light are emitted from a surface facing upward the optical working layer.

[0062] [Section 2] A light-emitting device as described in item 1, The optical element further has a light extraction surface from which the wavelength-converted light and the second emitted light are emitted, in a light-emitting device.

[0063] [Section 3] A light-emitting device as described in item 2, The first light-emitting element and the second light-emitting element are arranged such that the first light-emitting surface and the second light-emitting surface face each other with the optical member in between. The optical member comprises a first surface, a second surface opposite to the first surface, a third surface, and a fourth surface opposite to the third surface. The wavelength conversion member is positioned below the first surface, The first light-emitting element has a first light-emitting surface facing the third surface, and the first emitted light is incident on the third surface. The second light-emitting element has a second light-emitting surface facing the fourth surface, and the second emitted light is incident on the fourth surface. The second surface is the light extraction surface, The optical working layer is positioned diagonally within the optical member to the first and third surfaces of the light-emitting device. With the above configuration, by directly reflecting the second emitted light back to the light extraction surface, the components sent to the wavelength conversion member are reduced, and the luminescence efficiency can be increased without loss.

[0064] [Section 4] A light-emitting device according to any one of items 1 to 3, The light-emitting device has an optical layer that reflects light in the wavelength range of blue light and transmits light in the wavelength range longer than that of blue light.

[0065] [Section 5] A light-emitting device according to any one of items 1 to 4, The light-emitting device has an optical working layer that reflects light in the wavelength range of at least 430 nm to 480 nm and transmits light in the wavelength range of at least 500 nm.

[0066] [Section 6] A light-emitting device as described in any one of paragraphs 3 to 5 (excluding those not dependent on paragraph 3), further, A light-emitting device comprising a reflective and transmissive film provided on the fourth surface of the optical member, which transmits the second emitted light and reflects the wavelength-converted light that has passed through the optical working layer.

[0067] [Section 7] A light-emitting device as described in any one of paragraphs 3 to 6 (excluding those not dependent on paragraph 3), further, A first reflective film that reflects the first emitted light, the second emitted light, and the wavelength-converted light, A second reflective film that reflects the first emitted light, the second emitted light, and the wavelength-converted light, Equipped with, The optical member comprises a fifth surface intersecting the first, second, third, and fourth surfaces, and a sixth surface intersecting the first, second, third, and fourth surfaces and facing the fifth surface. The first reflective film is provided on the fifth surface, The second reflective film is a light-emitting device provided on the six surfaces.

[0068] [Section 8] A light-emitting device according to any one of items 1 to 7, A light-emitting device in which the first and second light-emitting colors are the same.

[0069] [Section 9] A light-emitting device as described in any one of paragraphs 2 to 8 (excluding those not dependent on paragraph 2), The first and second emission colors are blue light. A light-emitting device from which white light is emitted from the aforementioned light extraction surface.

[0070] [Section 10] A light-emitting device according to any one of items 1 to 9, A light-emitting device in which the difference between the main emission peak wavelength of the first light-emitting element and the main emission peak wavelength of the second light-emitting element is 20 nm or less.

[0071] [Section 11] A light-emitting device as described in any one of paragraphs 3 to 10 (excluding those not dependent on paragraph 3), A roughened region is provided on the second surface of the optical member. The light-emitting device wherein the second emitted light passes through the region and is emitted from the second surface. With the above configuration, the output light can be diffused on the emission side of the optical element.

[0072] [Section 12] A light-emitting device according to any one of items 1 to 11, A light-emitting device in which the first light-emitting element and the second light-emitting element are semiconductor lasers.

[0073] [Section 13] A light-emitting device according to any one of items 1 to 12, further, A light-emitting device comprising a drive unit capable of independently driving the first light-emitting element and the second light-emitting element to light up.

[0074] [Section 14] A light-emitting device according to any one of items 1 to 13, further, A light-emitting device comprising the first light-emitting element, an optical element, and a package for housing the second light-emitting element.

[0075] [Section 15] A light-emitting device as described in any one of paragraphs 3 to 14 (excluding those not dependent on paragraph 3), A light-emitting device wherein the upper end of the optical working layer does not intersect with the second surface, but intersects with the third surface below the upper end of the third surface. With the above configuration, the optical path length of the optical elements can be increased, thereby widening the spot diameter of the output light and allowing it to be emitted. [Industrial applicability]

[0076] The light-emitting devices described in each embodiment can be used in lighting fixtures such as smart lights and indirect lighting, vehicle headlights, head-mounted displays, projectors, displays, and the like. [Explanation of Symbols]

[0077] 100, 200, 300, 400... Light-emitting devices 10, 10A, 10B... First light-emitting element 11...First light exit surface 15…Submount 20, 20A, 20B, 20C... Second light-emitting element 21...Second light exit surface 30, 30A, 30B, 30C, 30D… Optical components 31…Front page 32…Second side 33…Third side 34…Fourth side 35…Fifth side 36…Sixth side 37...Optical action layer 38...first optical action surface 39…Second optical action surface 40...Wavelength conversion component 50…Package 51...Lid part 52...Base 53… Implemented circuit board 54…Frame members 60…Drive unit 70…Reflective transmissive film 71...First reflection-transmission film 72…Second reflective / transmissive film 80...Reflection film 81…First reflective film 82…Second reflective film

Claims

1. A first light-emitting element having a first light-emitting surface that emits first emitted light of a first emission color, A wavelength conversion member that emits wavelength-converted light obtained by wavelength conversion upon receiving the light of the first emission color, A second light-emitting element having a second light-emitting surface that emits a second emitted light of a second emission color, An optical component having an optical working layer with different reflectance and transmittance depending on the wavelength of light, A light-emitting device comprising, In the optical working layer, the first emitted light is reflected without being transmitted. The wavelength conversion member receives the first emitted light reflected by the optical working layer and emits the wavelength converted light. In the optical working layer, the wavelength-converted light is transmitted, and the second emitted light is not wavelength-converted by the wavelength-converting member and is reflected without being transmitted through the optical working layer. A light-emitting device from which the wavelength-converted light and the second emitted light are emitted from a surface facing upward the optical working layer.

2. A light-emitting device according to claim 1, The optical element further has a light extraction surface from which the wavelength-converted light and the second emitted light are emitted, in a light-emitting device.

3. A light-emitting device according to claim 2, The first light-emitting element and the second light-emitting element are arranged such that the first light-emitting surface and the second light-emitting surface face each other with the optical member in between. The optical member comprises a first surface, a second surface opposite to the first surface, a third surface, and a fourth surface opposite to the third surface. The wavelength conversion member is positioned below the first surface, The first light-emitting element has a first light-emitting surface facing the third surface, and the first emitted light is incident on the third surface. The second light-emitting element has a second light-emitting surface facing the fourth surface, and the second emitted light is incident on the fourth surface. The second surface is the light extraction surface, The optical working layer is positioned diagonally within the optical member to the first and third surfaces of the light-emitting device.

4. A light-emitting device according to claim 1, The light-emitting device comprises an optical layer which reflects light in the wavelength range of blue light and transmits light in the wavelength range longer than that of blue light.

5. A light-emitting device according to claim 4, The light-emitting device has an optical working layer that reflects light in the wavelength range of 430 nm to 480 nm and transmits light in the wavelength range of 500 nm or more.

6. The light-emitting device according to claim 3, further, A light-emitting device comprising a reflective and transmissive film provided on the fourth surface of the optical member, which transmits the second emitted light and reflects the wavelength-converted light that has passed through the optical working layer.

7. The light-emitting device according to claim 3, further, A first reflective film that reflects the first emitted light, the second emitted light, and the wavelength-converted light, A second reflective film that reflects the first emitted light, the second emitted light, and the wavelength-converted light, Equipped with, The optical member comprises a fifth surface intersecting the first, second, third, and fourth surfaces, and a sixth surface intersecting the first, second, third, and fourth surfaces and facing the fifth surface. The first reflective film is provided on the fifth surface, The second reflective film is a light-emitting device provided on the six surfaces.

8. A light-emitting device according to any one of claims 1 to 7, A light-emitting device in which the first and second light-emitting colors are the same.

9. A light-emitting device according to claim 2, The first and second emission colors are blue light. A light-emitting device from which white light is emitted from the aforementioned light extraction surface.

10. A light-emitting device according to any one of claims 1 to 7, A light-emitting device in which the difference between the main emission peak wavelength of the first light-emitting element and the main emission peak wavelength of the second light-emitting element is 20 nm or less.

11. A light-emitting device according to claim 3, A roughened region is provided on the second surface of the optical member. The light-emitting device wherein the second emitted light passes through the region and is emitted from the second surface.

12. A light-emitting device according to any one of claims 1 to 6, A light-emitting device in which the first light-emitting element and the second light-emitting element are semiconductor lasers.

13. A light-emitting device according to any one of claims 1 to 6, further, A light-emitting device comprising a drive unit capable of independently driving the first light-emitting element and the second light-emitting element to light up.

14. A light-emitting device according to any one of claims 1 to 6, further, A light-emitting device comprising the first light-emitting element, an optical element, and a package for housing the second light-emitting element.

15. A light-emitting device according to claim 3, A light-emitting device wherein the upper end of the optical working layer does not intersect with the second surface, but intersects with the third surface below the upper end of the third surface.

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