Light-emitting device, headlight, and vehicle equipped with the same

Abstract

To provide a light-emitting device that can reduce glare and has excellent durability, a headlight, and a vehicle equipped with the same.SOLUTION: A light-emitting device includes: a light-emitting element having an emission peak wavelength within the range of 400 nm or more and 490 nm or less; and a wavelength conversion member that has a first phosphor having an emission peak wavelength within the range of 480 nm or more and less than 580 nm, and a second phosphor having an emission peak wavelength within the range of 580 nm or more and 680 nm or less and having a composition different from that of the first phosphor. The light emitting device emits light having a first luminance ratio Ls / L of 0.9 or less, the first luminance ratio Ls / L being a ratio of the first effective radiation luminance Ls of the light emitted from the light-emitting device in consideration of the spectral sensitivity of the human S-cone and the human photopic standard luminous efficiency curve defined by CIE, with respect to the luminance L of the light emitted from the light-emitting device in consideration of the human photopic standard luminous efficiency curve. The first phosphor includes a rare earth aluminate phosphor having a composition represented by formula (1A).SELECTED DRAWING: Figure 3B

Description

[Technical field]

[0001] The present invention relates to a light-emitting device, a headlamp, and a vehicle equipped with the same. [Background technology]

[0002] The headlights of road transport vehicles such as four-wheeled motor vehicles and two-wheeled motor vehicles, tractor-type vehicles such as vehicles for leveling, transporting, and loading, and excavator-type vehicles for construction machinery such as vehicles for excavation, use lamps such as halogen lamps, HID lamps (High-Intensity Discharge Lamps), and light-emitting devices using semiconductor light-emitting elements as excitation light sources. For example, headlights for automobiles are installed symmetrically on the left and right sides of the front at a position lower than the driver's viewpoint. The headlights are equipped with lamps for high beams (headlights for driving) and lamps for low beams (headlights for passing other vehicles), and these can be switched. The high beams illuminate the area relatively far ahead, for example up to about 100 m, and the low beams illuminate the area slightly lower and closer than the high beams, for example about 40 m ahead.

[0003] For example, Patent Document 1 discloses a vehicle headlamp including a first lamp unit that is turned on in a low beam mode, and a first lamp unit and a second lamp unit that are turned on simultaneously in a high beam mode. Patent Document 1 discloses that the first lamp unit uses a white light emitting LED that emits light at a correlated color temperature of 4000K to 6500K as a light source, and the second lamp unit uses a metal halide lamp, a type of HID lamp that emits light at a correlated color temperature of 4000K to 5000K as a light source. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] JP 2005-141917 A Summary of the Invention [Problem to be solved by the invention]

[0005] The light emitted from the headlights can stimulate the vision of the driver of the preceding or oncoming vehicle, causing glare that makes it difficult to see and makes it uncomfortable. Glare is a sensation caused by inappropriate luminance distribution or extreme luminance contrast within the field of vision, and is accompanied by discomfort and a decrease in the ability to see (JIS Z9110). Furthermore, the light emitted from the headlights can also cause glare to the driver of the moving vehicle due to reflected light. An object of one aspect of the present invention is to provide a light-emitting device, a headlamp, and a vehicle including the same that can reduce glare and have improved durability. [Means for solving the problem]

[0006] A first aspect is a light emitting device including a wavelength conversion member including a light emitting element having an emission peak wavelength in the range of 400 nm or more and 490 nm or less, a first phosphor having an emission peak wavelength in the range of 480 nm or more and less than 580 nm, and a second phosphor having an emission peak wavelength in the range of 580 nm or more and 680 nm or less and having a composition different from that of the first phosphor, wherein the light emitting device emits light in which a first luminance ratio Ls / L, which is a ratio of a first effective radiance Ls of emission of the light emitting device in the range of 380 nm or more and 780 nm or less taking into account the standard relative luminous efficiency curve of human photopic vision specified by CIE (Commission Internationale de Illumination), is 0.9 or less, and is calculated from the following formula (1):

[0007]

number

[0008] A second aspect is a light emitting device including a wavelength conversion member including a light emitting element having a peak emission wavelength in the range of 400 nm or more and 490 nm or less, a first phosphor having a peak emission wavelength in the range of 480 nm or more and less than 580 nm, and a second phosphor having a peak emission wavelength in the range of 580 nm or more and 680 nm or less and having a composition different from that of the first phosphor, wherein the light emitting device emits light in which a second luminance ratio B / A, which is a ratio of a second effective radiance B of emission of the light emitting device in the range of 300 nm or more and 800 nm or less taking into account a scattering intensity curve for wavelength when the scattering intensity of Rayleigh scattering at a wavelength of 300 nm is set to 1, and which is derived from the following formula (2), is 0.104 or less, and the first phosphor includes a rare earth aluminate phosphor having a composition represented by the following formula (1A).

[0009]

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[0010] A third aspect is a headlamp including the light emitting device.

[0011] A fourth aspect is a vehicle equipped with the light emitting device or the headlight. Effect of the Invention

[0012] According to one aspect of the present invention, it is possible to provide a light-emitting device, a headlamp, and a vehicle equipped with the same that are capable of reducing glare and improving durability. [Brief description of the drawings]

[0013] [Figure 1A] This is the spectral sensitivity Gs(λ) of human S cones disclosed in Non-Patent Document 2. [Figure 1B] 1 shows the standard luminous efficiency curve V(λ) for human photopic vision defined by the CIE and disclosed in Non-Patent Document 2. [Figure 1C] This is a curve corresponding to VK(λ):K=1.260 disclosed in Non-Patent Document 2, and is an example of the spectral luminous efficiency VK(λ) corresponding to glare. [Diagram 2] FIG. 1 is a graph showing the intensity curve Dc(λ) of Rayleigh scattering, where the scattering intensity at a wavelength of 300 nm is taken as 1. [Figure 3A] FIG. 1 is a schematic plan view of a light emitting device. [Figure 3B] 1 is a schematic cross-sectional view of a light emitting device. [Figure 3C] 1 is an enlarged view of a part of a schematic cross section of a light emitting device. [Figure 4] FIG. [Diagram 5] FIG. [Figure 6] FIG. 4 is a diagram showing an emission spectrum of the light emitting device according to Example 1 before a reliability evaluation test. [Figure 7]FIG. 13 is a diagram showing the emission spectrum of the light emitting device according to Example 1 after a reliability evaluation test. [Figure 8] 13 is a binarized photograph of the light-transmitting body surface of the light-emitting device according to Example 1 after a reliability evaluation test. [Figure 9] 13 is a photograph of a binarized light-transmitting surface of the light-emitting device according to Comparative Example 1 after a reliability evaluation test. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0014] Hereinafter, an embodiment of the present invention will be described with reference to the drawings. However, the embodiment shown below is an example of a light-emitting device, a headlamp, and a vehicle equipped with the same for embodying the technical idea of ​​the present invention, and the present invention is not limited to the light-emitting device, the headlamp, and the vehicle equipped with the same shown below. In addition, the members shown in the claims are in no way limited to the members of the embodiments. In particular, the dimensions, materials, shapes, and relative arrangements of the components described in the embodiments are merely illustrative examples, and are not intended to limit the scope of the present invention, unless otherwise specified. The relationship between the color name and the chromaticity coordinates, the relationship between the wavelength range of light and the color name of monochromatic light, etc., are in accordance with JIS Z8110. In this specification, the content of each component in the composition refers to the total amount of the multiple substances present in the composition when multiple substances corresponding to each component are present in the composition, unless otherwise specified. In this specification, the full width at half maximum refers to the wavelength width at which the emission intensity is 50% of the emission intensity at the emission peak wavelength showing the maximum emission intensity in the emission spectrum.

[0015] Vehicle headlamps use various light sources, such as HID lamps, halogen lamps, and light-emitting devices using LEDs, depending on the characteristics of luminous flux and energy. The glare and apparent brightness that are perceived as dazzling differ depending on the light source. For example, the brightness of the road surface is also affected by blue light components and the correlated color temperature of light. Non-Patent Document 1 discloses an evaluation that LED light sources with a high correlated color temperature, for example 6600K, are perceived as dazzling by humans, regardless of whether they are elderly or not (Non-Patent Document 1: Hashimoto Hiroshi et al., "Effect of Differences in Color Temperature of White LEDs on Glare," Japan Automobile Research Institute, Preventive Safety Research Department, October 2006, Automobile Research, Vol. 28, No. 10, pp. 569 to 572). The glare that humans find unpleasant also differs depending on the decrease in retinal illuminance and the deterioration of rod cells, and glare may also change depending on the human age. Among the cone cells, which are photoreceptor cells present in the human retina, S cones photoreact to short-wavelength light. S cones have a peak sensitivity wavelength at around 440 nm. Non-Patent Document 2 describes a new spectral luminosity curve V(λ) for human photopic vision, which is used in the sidelight system of the CIE 1931 color system, and takes into account the spectral sensitivity Gs(λ) of human S cones at wavelength λ, which corresponds to glare. K The following formula (3) of (λ) is disclosed (Non-Patent Document 2: Kobayashi, Masaji et al., "Research on the Influence of the Spectral Distribution of Headlamp Light Source on Discomfort Glare," Society of Automotive Engineers of Japan, Inc. Academic Conference Preprints, No. 5 to 10, pp. 9 to 14). In this specification, the term "spectral radiance" is synonymous with the term "spectral distribution."

[0016]

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[0017] FIG. 1A shows the spectral sensitivity Gs(λ) of human S cones disclosed in Non-Patent Document 2. Based on FIG. 1A, the numerical value of the spectral sensitivity Gs(λ) of human S cones can be derived. The spectral sensitivity Gs(λ) of human S cones has a peak in the range of 380 nm or more and 550 nm or less. FIG. 1B shows the standard luminous efficiency curve V(λ) of human photopic vision defined by the CIE disclosed in Non-Patent Document 2. The relative values ​​shown in FIG. 1A to FIG. 1C are values ​​obtained by taking the peak top of the standard luminous efficiency curve V(λ) of human photopic vision defined by the CIE as 1. Based on FIG. 1B, the numerical value of the standard luminous efficiency curve V(λ) of human photopic vision defined by the CIE can be derived. FIG. 1C shows the standard luminous efficiency curve V(λ) of human photopic vision defined by the CIE. K (λ): This is the curve corresponding to K=1.260, and is the spectral luminosity V corresponding to glare, taking into account the standard luminosity curve for human photopic vision defined by the CIE and the spectral sensitivity of human S-cones. K (λ). K is a coefficient that determines the contribution of the human S-cone spectral sensitivity Gs(λ). The coefficient K for a halogen light bulb is 1.260.

[0018] The luminance L of the light emitted by a light emitting device is calculated by the following formula (4). The luminance L of the light emitted by a light emitting device is the integral value of the spectral radiance S(λ) of the light emitting device in the range of 380 nm to 780 nm and the standard luminous efficiency curve V(λ) of human photopic vision defined by the CIE.

[0019]

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[0020] The first effective radiance Ls of the light emitted by the light emitting device is calculated by the following formula (5). The first effective radiance Ls of the light emitted by the light emitting device is calculated by dividing the spectral radiance S(λ) of the light emitting device in the range of 380 nm to 780 nm and the human spectral luminous efficiency V corresponding to the glare expressed by the above formula (3). K (λ) (=K·Gs(λ)+V(λ)) is integrated with the coefficient K (=1.260) for halogen bulbs to obtain the V obtained by the above formula (3). K This value is obtained by dividing the peak top of (λ) by 2.3.

[0021]

number

[0022] The first luminance ratio Ls / L of the light emitted by the light emitting device is the ratio of the first effective radiance Ls of the light emitted by the light emitting device, taking into account the standard luminous efficiency curve for human photopic vision defined by the CIE and the spectral sensitivity of human S-cones, to the luminance L of the light emitted by the light emitting device, taking into account the standard luminous efficiency curve for human photopic vision defined by the CIE. The first luminance ratio Ls / L represents the degree of reduction in glare of the light emitted by the light emitting device.

[0023] The light emitting device of the first embodiment includes a light emitting element having a peak emission wavelength in the range of 400 nm to 490 nm, a first phosphor having a peak emission wavelength in the range of 480 nm to less than 580 nm, and a second phosphor having a peak emission wavelength in the range of 580 nm to 680 nm and a composition different from that of the first phosphor. The light emitting device emits light with a first luminance ratio Ls / L of 0.9 or less, which is derived from the following formula (1).

[0024]

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[0025] If the first luminance ratio Ls / L of the light emitted by the light emitting device is 0.9 or less, the light emitted from the light emitting device has reduced glare. If the first luminance ratio Ls / L of the light emitted by the light emitting device exceeds 0.9, the luminance ratio becomes close to the luminance L of the light emitted by the light emitting device without considering the spectral sensitivity of the human S cone, and the glare is not reduced. In order to reduce the glare that humans find unpleasant, the first luminance ratio Ls / L of the light emitted by the light emitting device is preferably 0.85 or less, more preferably 0.83 or less, even more preferably 0.80 or less, and may be 0.7 or less. Taking into account the spectral sensitivity of the human S cone, the first luminance ratio Ls / L of the light emitted by the light emitting device may be 0.1 or more, may be 0.2 or more, is preferably 0.3 or more, is more preferably 0.4 or more, and is even more preferably 0.5 or more.

[0026] The light emitting device emitting light having a first luminance ratio Ls / L of 0.9 or less preferably emits light having a second luminance ratio A / B of 0.104 or less, which will be described later. The light emitting device emitting light having a first luminance ratio Ls / L of 0.9 or less and a second luminance ratio A / B of 0.104 or less, which will be described later, can make the light reach a long distance while reducing glare. The light emitting device of the first embodiment, which can make the light reach a long distance while reducing glare, can be used in a headlight and a vehicle equipped with this headlight. The headlight using the light emitting device of the first embodiment and the vehicle equipped with this headlight can make the light reach a long distance while reducing the glare of the light emitted from the headlight and the vehicle.

[0027] In the light emitting device of the first embodiment, the first phosphor contains a rare earth aluminate phosphor having a composition represented by the following formula (1A). Ln 1 3-e Ce e (Al 1-a Ga a )5O 12 (1A) (In formula (1A), Ln 1 is at least one element selected from the group consisting of Y, Gd, Tb and Lu, and a and e satisfy 0≦a≦0.5 and 0.019≦e≦0.2.

[0028] The rare earth aluminate phosphor represented by the formula (1A) has a large variable e, which represents the molar ratio of Ce, an activator element in the composition, of 0.019 or more and 0.2 or less (0.019≦e≦0.2), so that the content of the first phosphor contained in the light emitting device can be reduced, and even if the content of the first phosphor is small, the light emitting device can emit light of a desired color tone. In addition, the light emitting device has a large variable e, which represents the molar ratio of Ce, an activator element in the composition of the rare earth aluminate phosphor represented by the formula (1A), of 0.019 or more and 0.2 or less (0.019≦e≦0.2), so that the content of the first phosphor contained in the light emitting device can be reduced, the heat generated from the phosphor can be reduced, deterioration of the light emitting device due to heat, such as cracking and cracking, can be suppressed, and the durability of the light emitting device can be improved.

[0029] In the formula (1A), the variable e representing the molar ratio of Ce, which is an activation element, may be in the range of 0.019 to 0.118 (0.019≦e≦0.118) or in the range of 0.019 to 0.115 (0.019≦e≦0.115). In the formula (1A), the variable a representing the molar ratio of Ga, which is the product of the variables a and 5, may be in the range of 0 to 0.45 (0≦a≦0.45) or in the range of 0 to 0.40 (0≦a≦0.40).

[0030] The light emitting device of the second embodiment includes a light emitting element having a peak emission wavelength in the range of 440 nm to 490 nm, a first phosphor having a peak emission wavelength in the range of 480 nm to less than 580 nm, and a second phosphor having a peak emission wavelength in the range of 580 nm to 680 nm and a composition different from that of the first phosphor. The light emitting device emits light having a second luminance ratio B / A of 0.104 or less, which is the ratio of a second effective radiance B of the light emitting device in the range of 300 nm to 800 nm, taking into account a scattering intensity curve for wavelength when the scattering intensity of Rayleigh scattering at a wavelength of 300 nm is set to 1, to a radiance A of the light emitting device in the range of 300 nm to 800 nm.

[0031]

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[0032] The scattering of light caused by the interaction between light and particles is determined by the relative relationship between the wavelength λ of light and the size D of the particles. The size D of the particles contained in the air is much smaller than the wavelength λ of light. Rayleigh scattering is the scattering of light by particles smaller than the wavelength of light. In air, the shorter the wavelength of light, the more likely it is to be scattered. If the scattering of light is suppressed, the light can be made to reach a long distance. A light-emitting device that can make light reach a long distance can be suitably used for a headlamp for a high beam mode that illuminates a relatively long distance ahead, for example, about 100 m. The light-emitting device of the second embodiment can make light reach a relatively long distance by suppressing scattering. In addition, a headlamp using the light-emitting device of the second embodiment and a vehicle equipped with this headlamp can make light reach a relatively long distance.

[0033] The radiance A of the light emitted by the light emitting device is calculated by the following formula (6): The radiance A of the light emitted by the light emitting device is the integral value of the spectral radiance S(λ) of the light emitting device in the range of 300 nm or more and 800 nm or less.

[0034]

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[0035] FIG. 2 shows a scattering intensity curve Dc(λ) versus wavelength, where the scattering intensity of Rayleigh scattering at a wavelength of 300 nm is taken as 1.

[0036] The second effective radiance B of the light emitted by the light emitting device is derived by the following formula (7). The second effective radiance B of the light emitted by the light emitting device is the integral value of the scattering intensity curve Dc(λ) and the spectral radiance S(λ) of the light emitting device in the range of 300 nm or more and 800 nm or less.

[0037]

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[0038] The second luminance ratio B / A of the emission of the light emitting device is the ratio of the second effective radiance B of the emission of the light emitting device in the range of 300 nm to 800 nm inclusive, taking into account the scattering intensity curve for wavelength when the scattering intensity of Rayleigh scattering at a wavelength of 300 nm is set to 1, to the radiance A of the emission of the light emitting device in the range of 300 nm to 800 nm inclusive. The second luminance ratio B / A represents the degree of scattering of the emission of the light emitting device.

[0039] If the second luminance ratio B / A of the light emitted by the light emitting device is 0.104 or less, scattering is suppressed, and light that reaches a relatively long distance is emitted from the light emitting device. If the second luminance ratio B / A of the light emitted by the light emitting device exceeds 0.104, it becomes close to the radiance A of the light emitted by the light emitting device without taking Rayleigh scattering into consideration. In order to suppress scattering and emit light that reaches a relatively long distance, the second luminance ratio B / A of the light emitted by the light emitting device is preferably 0.102 or less, more preferably 0.100 or less, even more preferably 0.099 or less, even more preferably 0.098 or less, particularly preferably 0.090 or less, and even more particularly preferably 0.085 or less. In order to suppress scattering of light, the second luminance ratio B / A of the light emitted by the light emitting device is preferably 0.104 or less, and the second luminance ratio B / A of the light emitted by the light emitting device is preferably a small value, but if the second luminance ratio B / A of the light emitted by the light emitting device becomes too small, the spectral radiance becomes small, and it may be difficult to make the light reach a relatively long distance. Taking into account Rayleigh scattering, the light emitted by the light emitting device may have a second luminance ratio B / A of 0.01 or more, or 0.02 or more, preferably 0.03 or more, more preferably 0.04 or more, and even more preferably 0.05 or more.

[0040] A light emitting device that emits light with a second luminance ratio B / A of 0.104 or less preferably emits light with the above-mentioned first luminance ratio Ls / L of 0.9 or less. A light emitting device that emits light with a second luminance ratio A / B of 0.104 or less and a first luminance ratio Ls / L of 0.9 or less can project light relatively far and reduce glare.

[0041] In the light emitting device of the second embodiment, the first phosphor includes a rare earth aluminate phosphor having a composition represented by the formula (1A). In the formula (1A), the variable e representing the molar ratio of Ce, which is an activator element, may be in the range of 0.019 to 0.118 (0.019≦e≦0.118), or in the range of 0.019 to 0.115 (0.019≦e≦0.115). The rare earth aluminate phosphor represented by the formula (1A) has a large variable e representing the molar ratio of Ce, which is an activator element in the composition, which is 0.019 to 0.2 (0.019≦e≦0.2). Therefore, the content of the first phosphor contained in the light emitting device can be reduced, and even if the content of the first phosphor is small, the light emitting device can emit light of a desired color tone. Furthermore, since the light emitting device has a large variable e, which represents the molar ratio of Ce, an activator element in the composition of the rare earth aluminate phosphor represented by formula (1A), the content of the first phosphor contained in the light emitting device can be reduced, the heat emitted from the phosphor can be reduced, deterioration of the light emitting device due to heat can be suppressed, and the durability of the light emitting device can be increased.

[0042] Hereinafter, a light emitting device emitting light with a first luminance ratio Ls / L of 0.9 or less and / or a light emitting device emitting light with a second luminance ratio B / A of 0.104 or less will be described. The light emitting device emitting light with a first luminance ratio Ls / L of 0.9 or less and the light emitting device emitting light with a second luminance ratio B / A of 0.104 or less preferably have correlated color temperatures in the same range, and may be light emitting devices of the same form using the same members.

[0043] The light emitting device preferably emits light having a correlated color temperature of 1800 K or more and 5000 K or less, and more preferably emits light having a correlated color temperature of 2000 K or more and 5000 K or less. For example, a light emitting device provided in a headlight emits light with a lower correlated color temperature, which can reduce glare felt by the driver of a preceding vehicle, an oncoming vehicle, or the traveling vehicle itself.

[0044] Light emitting element The light-emitting element has an emission peak wavelength in the range of 400 nm to 490 nm. The emission peak wavelength of the light-emitting element is preferably in the range of 420 nm to 480 nm, and may be in the range of 440 nm to 460 nm. At least a part of the light emitted by the light-emitting element is used as excitation light for the first phosphor and the second phosphor, so it is preferable that the light-emitting element has an emission peak wavelength that easily excites those phosphors. The full width at half maximum of the emission spectrum of the light-emitting element is preferably 30 nm or less, more preferably 25 nm or less, and even more preferably 20 nm or less. For example, it is preferable to use a semiconductor light-emitting element using a nitride-based semiconductor as the light-emitting element. This makes it possible to obtain a light-emitting device that is highly efficient, has a high linearity of output relative to input, and is stable against mechanical shock.

[0045] First phosphor The first phosphor is excited by the emission of the light emitting element having an emission peak wavelength in the range of 400 nm to 490 nm, and emits light having an emission peak wavelength in the range of 480 nm to less than 580 nm. The first phosphor preferably has a full width at half maximum of an emission spectrum in the range of 90 nm to 125 nm, and may be in the range of 100 nm to 124 nm, or may be in the range of 110 nm to 123 nm. When the first phosphor has an emission peak wavelength in the range of 480 nm to less than 580 nm, the excitation light from the light emitting element is wavelength-converted, and a mixed color light of the light from the light emitting element and the light wavelength-converted by the first phosphor and the second phosphor is emitted from the light emitting device.

[0046] The first phosphor preferably includes a rare earth aluminate phosphor having a composition represented by the formula (1A) above, and at least one selected from the group consisting of first nitride phosphors having a composition represented by the following formula (1B): La w Ln 2 x Ce z Si6N y (1B) (In formula (1B), Ln 2contains at least one element selected from the group consisting of Y and Gd as an essential component, and may contain at least one element selected from the group consisting of Sc and Lu. When the total amount of Ln 2 elements is 100 mol%, the total amount of Y and Gd contained in Ln 2 is 90 mol% or more, and w, x, y, and z satisfy 1.2 ≦ w ≦ 2.2, 0.5 ≦ x ≦ 1.2, 10 ≦ y ≦ 12, 0.5 ≦ z ≦ 1.2, 1.80 < w + x < 2.40, and 2.9 ≦ w + x + z ≦ 3.1.)

[0047] The first phosphor may contain at least one phosphor selected from the group consisting of alkaline earth metal aluminate phosphors and alkaline earth metal halosilicate phosphors. The alkaline earth metal aluminate phosphor contains at least strontium and is a phosphor activated with europium. For example, it has a composition represented by the following formula (1C). The alkaline earth metal halosilicate contains at least calcium and chlorine and is a phosphor activated with europium. For example, it has a composition represented by the following formula (1D). Sr4Al 14 O 25 :Eu (1C) (Ca,Sr,Ba)8MgSi4O 16 (F,Cl,Br)2:Eu (1D) In formula (1C), a part of Sr may be substituted with at least one element selected from the group consisting of Mg, Ca, Ba, and Zn. The alkaline earth metal aluminate phosphor having the composition represented by formula (1C) and the alkaline earth metal halosilicate phosphor having the composition represented by formula (1D) have an emission peak wavelength in the range of 480 nm or more and less than 520 nm, preferably in the range of 485 nm or more and 515 nm or less. The alkaline earth metal aluminate phosphor having a composition represented by formula (1C) and the alkaline earth metal halosilicate phosphor having a composition represented by formula (1D) have an emission spectrum with a full width at half maximum of, for example, 30 nm or more, preferably 40 nm or more, and more preferably 50 nm or more, and for example, 80 nm or less, preferably 70 nm or less. In this specification, in the formula showing the composition of the phosphor, the part before the colon (:) represents the molar ratio of each element in 1 mole of the composition of the host crystal and the phosphor, and the part after the colon (:) represents the activator element. Furthermore, in this specification, in the formula showing the composition of the phosphor, a plurality of elements separated by a comma (,) means that at least one of these elements is contained in the composition, and two or more of the elements may be contained in combination.

[0048] The first phosphor may include at least one phosphor selected from the group consisting of a β-sialon phosphor, a first sulfide phosphor, a scandium-based phosphor, an alkaline earth metal silicate phosphor, and a lanthanoid silicon nitride phosphor. The β-sialon phosphor has a composition represented by the following formula (1E), for example. The first sulfide phosphor has a composition represented by the following formula (1F), for example. The scandium-based phosphor has a composition represented by the following formula (1G), for example. The alkaline earth metal silicate phosphor has a composition represented by the following formula (1H) or a composition represented by the following formula (1J), for example. The lanthanoid silicon nitride phosphor has a composition represented by the following formula (1K), for example. S 6-g Al g O g N 8-g :Eu(0 <g≦4.2) (1E) (Sr,M 3 )Ga2S4:Eu (1F) (In formula (1F), M 3 is at least one element selected from the group consisting of Be, Mg, Ca, Ba, and Zn. (Ca,Sr)Sc2O4:Ce (1G) (Ca,Sr)3(Sc,Mg)2Si3O 12 :Ce (1H) (Ca,Sr,Ba)2SiO4:Eu (1J) (La,Y,Gd,Lu)3Si6N 11 :Ce (1K)

[0049] The β-sialon phosphor, the first sulfide phosphor, the scandium phosphor, the alkaline earth metal silicate phosphor, and the lanthanoid silicon nitride phosphor each have an emission peak wavelength within the range of 520 nm or more and less than 580 nm, and preferably within the range of 525 nm or more and 565 nm or less. The β-sialon phosphor, the first sulfide phosphor, the scandium phosphor, the alkaline earth metal silicate phosphor, and the lanthanoid nitride phosphor each have a full width at half maximum in the emission spectrum of, for example, 20 nm or more, preferably 30 nm or more, and for example, 120 nm or less, preferably 115 nm or less.

[0050] The first phosphor may include at least one phosphor selected from the group consisting of a rare earth aluminate phosphor having a composition represented by the formula (1A), a first nitride phosphor having a composition represented by the formula (1B), an alkaline earth metal aluminate phosphor having a composition represented by the formula (1C), an alkaline earth metal halosilicate phosphor having a composition represented by the formula (1D), a β-sialon phosphor having a composition represented by the formula (1E), a first sulfide phosphor having a composition represented by the formula (1F), a scandium-based phosphor having a composition represented by the formula (1G), an alkaline earth metal silicate phosphor having a composition represented by the formula (1H), an alkaline earth metal silicate phosphor having a composition represented by the formula (1J), and a lanthanoid silicon nitride phosphor having a composition represented by the formula (1K). The first phosphor may include at least one phosphor having a composition represented by the formula (1A) alone, or may include two or more phosphors.

[0051] Second phosphor The second phosphor is excited by the emission of the light emitting element having an emission peak wavelength in the range of 400 nm to 490 nm, emits light having an emission peak wavelength in the range of 580 nm to 680 nm, and has a composition different from that of the first phosphor. The second phosphor preferably has a full width at half maximum in the emission spectrum in the range of 3 nm to 15 nm. As such a second phosphor, for example, it is preferable to include a fluoride phosphor having a composition represented by the following formula (2C), or a fluoride phosphor having a composition represented by the following formula (2C'). Alternatively, it is preferable to include a full width at half maximum in the emission spectrum in the range of 60 nm to 125 nm. As such a second phosphor, for example, it is preferable to include a second nitride phosphor having a composition represented by the following formula (2A), a third nitride phosphor having a composition represented by the following formula (2B), or an α-sialon phosphor having a composition represented by the following formula (2G). The second phosphor converts the wavelength of the excitation light from the light emitting element, and a mixed color light of the light from the light emitting element and the light wavelength-converted by the first phosphor and the second phosphor is emitted from the light emitting device.

[0052] The second phosphor preferably includes at least one selected from the group consisting of a second nitride phosphor having a composition represented by the following formula (2A), a third nitride phosphor having a composition represented by the following formula (2B), a fluoride phosphor having a composition represented by the following formula (2C), a fluoride phosphor having a composition represented by the following formula (2C') which is different from the composition of the following formula (2C), and an α-sialon phosphor having a composition represented by the following formula (2G). In this specification, the second nitride phosphor having a composition represented by the following formula (2A) may be referred to as a BSESN phosphor, and the third nitride phosphor having a composition represented by the following formula (2B) may be referred to as a SCASN phosphor. M 1 2Si5N8:Eu (2A) (In formula (2A), M 1 is an alkaline earth metal element including at least one selected from the group consisting of Ca, Sr, and Ba. Sr q Ca s Al t S uN v : Eu (2B) (In formula (2B), q, s, t, u, and v satisfy 0 ≦ q < 1, 0 < s ≦ 1, q + s ≦ 1, 0.9 ≦ t ≦ 1.1, 0.9 ≦ u ≦ 1.1, and 2.5 ≦ v ≦ 3.5, respectively.) A c [M 2 1-b Mn 4+ b F d (2C) (In formula (2C), A includes at least one selected from the group consisting of K + , Li + , Na + , Rb + , Cs + and NH4 + , and among them, K + is preferred. M 2 includes at least one element selected from the group consisting of Group 4 elements and Group 14 elements, and among them, Si and Ge are preferred. b satisfies 0 < b < 0.2, and c is the absolute value of the charge of the [M 2 1-b Mn 4+ b F d ion, and d satisfies 5 < d < 7.) A’ c’ [M 2 ’ 1-b’ Mn 4+ b’ F d’ (2C’) (In formula (2C’), A’ includes at least one selected from the group consisting of K + , Li + , Na + , Rb + , Cs + and NH4 + , and among them, K + is preferred. M 2 ’ includes at least one element selected from the group consisting of Group 4 elements, Group 13 elements, and Group 14 elements, and among them, Si and Al are preferred. b’ satisfies 0 < b’ < 0.2, and c’ is the absolute value of the charge of the [M 2 ’ 1-b’ Mn 4+ b’F d’ is the absolute value of the charge of the ion, and d’ satisfies 5 < d’ < 7.) M 8 v3 Si 12-(w3+x3) Al w3+x3 O x3 N 16-x3 :Eu (2G) (In formula (2G), M 8 includes at least one element selected from the group consisting of Li, Mg, Ca, Sr, Y, and lanthanoid elements (excluding La and Ce). v3, w3, and x3 each satisfy 0 < v3 ≤ 2.0, 2.0 ≤ w3 ≤ 6.0, and 0 ≤ x3 ≤ 1.0.)

[0053] The second phosphor may contain at least one phosphor selected from the group consisting of fluorogermanate phosphors, fourth nitride phosphors, and second sulfide phosphors. The fluorogermanate phosphor has, for example, a composition represented by the following formula (2D). The fourth nitride phosphor has, for example, a composition represented by the following formula (2E). The second sulfide phosphor has, for example, a composition represented by the following formula (2F). (i - j)MgO·(j / 2)Sc2O3·kMgF2·mCaF2·(1 - n)GeO2·(n / 2)M 4 2O3:Mn (2D) (In formula (2D), M 4 is at least one selected from the group consisting of Al, Ga, and In. i, j, k, m, n, and z each satisfy 2 ≤ i ≤ 4, 0 ≤ j < 0.5, 0 < k < 1.5, 0 ≤ m < 1.5, and 0 ≤ n < 0.5.) M 5 v2 M 6 w2 Al 3-y2 Si y2 N z2 :M 7 (2E) (In formula (2E), M 5 is at least one element selected from the group consisting of Ca, Sr, Ba, and Mg, and M 6 is at least one element selected from the group consisting of Li, Na, and K, and M 7is at least one element selected from the group consisting of Eu, Ce, Tb, and Mn, and v2, w2, y2, and z2 satisfy 0.80 ≦ v2 ≦ 1.05, 0.80 ≦ w2 ≦ 1.05, 0 ≦ y2 ≦ 0.5, and 3.0 ≦ z2 ≦ 5.0, respectively.) (Ca,Sr)S:Eu (2F)

[0054] The fluorogermanate phosphor having the composition represented by formula (2D) may have the composition represented by the following formula (2d). 3.5MgO·0.5MgF2·GeO2:Mn (2d)

[0055] The fourth nitride phosphor having the composition represented by formula (2E) may have the composition represented by the following formula (2e). M 5 v2 M 6 w2 M 7 x2 Al 3-y2 Si y2 N z2 (2e) (In formula (2e), M 5 , M 6 , and M 7 are synonymous with M 5 , M 6 , and M 7 in formula (2E), respectively, and are at least one element selected from the group consisting of Ce, Tb, and Mn, and v2, w2, y2, and z2 are synonymous with v2, w2, y2, and z2 in formula (2E), respectively, and x2 satisfies 0.001 < x2 ≦ 0.1.)

[0056] The fluorogermanate phosphor, the fourth nitride phosphor, and the second sulfide phosphor each have an emission peak wavelength in the range of 580 nm or more and 680 nm or less, preferably in the range of 600 nm or more and 630 nm or less. The fluorogermanate phosphor, the fourth nitride phosphor, and the second sulfide phosphor each have a full width at half maximum of the emission peak in the emission spectrum of, for example, 5 nm or more and 100 nm or less, preferably 6 nm or more and 90 nm or less.)

[0057] The second phosphor preferably includes at least one selected from the group consisting of a second nitride phosphor having a composition represented by the formula (2A), a third nitride phosphor having a composition represented by the formula (2B), a fluoride phosphor having a composition represented by the formula (2C), a fluoride phosphor having a composition represented by the formula (2C'), a fluorogermanate phosphor having a composition represented by the formula (2D), a fourth nitride phosphor having a composition represented by the formula (2E), a second sulfide phosphor having a composition represented by the formula (2F), and an α-sialon phosphor having a composition represented by the formula (2G). The second phosphor may include at least one phosphor alone, or may include two or more phosphors.

[0058] It is more preferable that the second phosphor contains at least one selected from the group consisting of a second nitride phosphor (BSESN phosphor) having a composition represented by formula (2A), a third nitride phosphor (SCASN phosphor) having a composition represented by formula (2B), and an α-sialon phosphor having a composition represented by formula (2G). At least one second phosphor selected from the group consisting of a BSESN phosphor, a SCASN phosphor, and an α-sialon phosphor has good temperature characteristics and exhibits little change in emission energy due to temperature changes. For example, a light emitting device including a wavelength conversion member containing a rare earth aluminate phosphor having a composition represented by the formula (1A) as the first phosphor and at least one selected from the group consisting of a BSESN phosphor, an SCASN phosphor, and an α-sialon phosphor as the second phosphor has good temperature characteristics of the first phosphor and the second phosphor, and therefore, even when used in a cold atmosphere of -40°C or a high temperature atmosphere exceeding 100°C, the rate of change of the first luminance ratio Ls / L is small while maintaining the first luminance ratio Ls / L at 0.9 or less, and is not easily affected by the ambient temperature of the usage environment, and can emit light with reduced glare from the light emitting device. Even when the temperature of the usage environment of the light emitting device changes while maintaining the first luminance ratio Ls / L at 0.9 or less, a light emitting device that can emit light with a small rate of change of the first luminance ratio Ls / L may be said to have good temperature characteristics. A light emitting device including a wavelength conversion member containing a rare earth aluminate phosphor having a composition represented by the formula (1A) as a first phosphor and at least one selected from the group consisting of a BSESN phosphor, a SCASN phosphor, and an α-sialon phosphor as a second phosphor has good temperature characteristics of the first phosphor and the second phosphor, and is therefore less susceptible to the ambient temperature of the usage environment, and can emit light from the light emitting device that has a small rate of change in the second luminance ratio B / A while maintaining the second luminance ratio B / A at 0.104 or less, is less susceptible to the ambient temperature of the usage environment, and suppresses scattering and reaches a relatively long distance. A light emitting device that can emit light with a small rate of change in the second luminance ratio B / A even when the temperature of the usage environment of the light emitting device changes while maintaining the second luminance ratio B / A at 0.104 or less may be said to have good temperature characteristics.

[0059] The phosphor including the first phosphor and the second phosphor preferably has an average particle size measured by a Fisher Sub-Sieve Sizer (hereinafter also referred to as "FSSS") method in the range of 5 μm to 40 μm, more preferably in the range of 6 μm to 35 μm, and even more preferably in the range of 7 μm to 30 μm. If the average particle size of the phosphor is in the range of 5 μm to 40 μm, the phosphor efficiently absorbs light emitted from an excitation light source and converts the wavelength, and light with reduced glare or light with suppressed light scattering that reaches a relatively long distance can be emitted from the light emitting device.

[0060] The rare earth aluminate phosphor having the composition represented by formula (1A) preferably has an average particle size measured by FSSS method within the range of 15 μm to 40 μm, more preferably within the range of 16 μm to 35 μm, and even more preferably within the range of 17 μm to 30 μm. If the rare earth aluminate phosphor having the composition represented by formula (1A) has a relatively large average particle size measured by FSSS method within the range of 15 μm to 40 μm, the content of the first phosphor contained in the light emitting device can be reduced, and even if the content of the first phosphor is small, the light emitting device can emit light of a desired color tone.

[0061] Light-emitting device The form of the light emitting device will be described. FIG. 3A shows an example of the light emitting device, and is a schematic plan view of the light emitting device 101. FIG. 3B is a schematic cross-sectional view of the light emitting device 101 shown in FIG. 3A along line III-III'. The light emitting device 101 includes a light emitting element 10 having an emission peak wavelength in the range of 400 nm to 490 nm, and a wavelength conversion member 40 including a wavelength conversion body 41 including a first phosphor 71 and a second phosphor 72 that are excited by light from the light emitting element 10 and emit light, and a transparent body 42 in which the wavelength conversion body 41 is arranged. The light emitting element 10 is flip-chip mounted on the substrate 1 via bumps that are conductive members 60. The wavelength conversion body 31 of the wavelength conversion member 40 is provided on the light emitting surface of the light emitting element 10 via an adhesive layer 80. The light emitting element 10 and the wavelength conversion member 40 have their sides covered by a covering member 90 that reflects light. The wavelength converter 41 includes a first phosphor 71 that is excited by light from the light emitting element 10 and has an emission peak wavelength in the range of 480 nm to less than 580 nm, and a second phosphor 72 that has an emission peak wavelength in the range of 580 nm to 680 nm and has a composition different from that of the first phosphor 71. The light emitting element 10 receives power from the outside of the light emitting device 101 via wiring and a conductive member 60 formed on the substrate 1, and can cause the light emitting device 101 to emit light. The light emitting device 101 may include a semiconductor element 50 such as a protective element for protecting the light emitting element 10 from destruction due to application of an excessive voltage. The covering member 90 is provided so as to cover, for example, the semiconductor element 50. Each member used in the light emitting device will be described below. For details, the disclosure of JP 2014-112635 A can be referenced.

[0062] Wavelength conversion material The wavelength conversion member may be a wavelength conversion body including a phosphor and a light-transmitting material, or may further include a light-transmitting body on which the wavelength conversion body is arranged. The wavelength conversion body preferably includes a first phosphor and a second phosphor, and a light-transmitting material. The wavelength conversion body may be formed in a plate-like, sheet-like or layer-like shape. The wavelength conversion member may include a wavelength conversion body in a shape other than a plate-like, sheet-like or layer-like shape. The wavelength conversion member preferably includes a wavelength conversion body including a first phosphor and a second phosphor, and a light-transmitting material, and the wavelength conversion member preferably includes a wavelength conversion body having a total amount of the first phosphor and the second phosphor in a range of 50 parts by mass or more and 500 parts by mass or less per 100 parts by mass of the light-transmitting material. If the total amount of the first phosphor and the second phosphor contained in the wavelength converter is within a range of 50 parts by mass to 500 parts by mass with respect to 100 parts by mass of the translucent material, the total amount of the first phosphor and the second phosphor is relatively small with respect to the translucent material, and the heat generated when the phosphor absorbs the excitation light and emits light can be reduced, deterioration of the light emitting device due to heat can be suppressed, and the durability of the light emitting device can be improved. The total amount of the first phosphor and the second phosphor contained in the wavelength converter may be within a range of 80 parts by mass to 400 parts by mass, 90 parts by mass to 350 parts by mass, 100 parts by mass to 300 parts by mass, or 100 parts by mass to 270 parts by mass with respect to 100 parts by mass of the translucent material. The total amount of the first phosphor and the second phosphor is also referred to as the total amount of phosphors.

[0063] The wavelength conversion member includes a wavelength converter including a first phosphor and a second phosphor and a light-transmitting material, and the wavelength converter preferably includes a high-concentration layer in which the filling rate of the first phosphor and the second phosphor is high and the concentration of the first phosphor and the second phosphor is high in the thickness direction of the cross section, and a low-concentration layer in which the filling rate of the first phosphor and the second phosphor is low and the concentration of the first phosphor and the second phosphor is low. By including a high-concentration layer in which the filling rate of the first phosphor and the second phosphor is high, even if the total amount of phosphor relative to the light-transmitting material is small, the wavelength converter is less likely to break or crack. The wavelength converter is preferably arranged such that the high-concentration layer is located on the light-emitting element side. By arranging the high-concentration layer on the light-emitting element side, the wavelength converter can dissipate heat generated from the light-emitting element through the first phosphor and the second phosphor in the wavelength converter. The filling rate of the phosphor can be measured by observing the cross section of the wavelength converter or the cross section of the wavelength conversion member with a scanning electron microscope (SEM) and measuring the filling rate of the phosphor from the area ratio of the resin to the phosphor in the cross section. A high-concentration layer with a high phosphor filling rate refers to a layer in which the area of ​​the phosphor is higher than the area of ​​the resin in the cross section of the wavelength converter or the cross section of the wavelength conversion member. A low-concentration layer with a low phosphor filling rate refers to a layer in which the area of ​​the phosphor is lower than the area of ​​the resin in the cross section of the wavelength converter or the cross section of the wavelength conversion member. The low-concentration layer may be a layer in which there is substantially no phosphor, there is no area of ​​the phosphor, and only the area of ​​the resin can be confirmed. In the cross section of the wavelength converter observed by SEM, the ratio of the thickness of the high-concentration layer to the thickness of the low-concentration layer may be 40% or less, 35% or less, 34% or less, 3% or more, or 5% or more, when the total thickness of the wavelength converter is taken as 100%. The higher the ratio of the thickness of the low-concentration layer, the lower the ratio of the thickness of the high-concentration layer, and the higher the filling rate of the first phosphor and the second phosphor contained in the high-concentration layer, and the higher the density of the high-concentration layer. In order to suppress breakage or cracking of the wavelength converter and to improve heat dissipation, it is preferable that the filling rate of the first phosphor and the second phosphor in the high concentration layer is high and the density of the first phosphor and the second phosphor is high.

[0064] Fig. 3C is a partially enlarged view of a part P1 of the schematic cross section of the light emitting device shown in Fig. 3B. For the purpose of explanation, Fig. 3C may be on a different scale from Fig. 3B.

[0065] The wavelength converter 41 includes a high-concentration layer 41a having a high filling rate of the first phosphor 71 and the second phosphor 72, and a low-concentration layer 41b having a low filling rate of the first phosphor 71 and the second phosphor 72, with the high-concentration layer 41a being disposed on the light-emitting element 10 side. The low-concentration layer 41b of the wavelength converter 41 is disposed on the light-transmitting body 42 side. The wavelength converter 41 is provided on the light-emitting surface of the light-emitting element 10 via an adhesive layer 80.

[0066] Since high-output light-emitting devices are being used in headlamps, wavelength conversion members having high heat resistance, such as a wavelength-converting member in which a resin composition containing a phosphor is applied to a light-transmitting body made of heat-resistant glass, or a sintered body containing a phosphor and a light-transmitting material, may be used. The phosphor contained in the wavelength conversion member having high heat resistance is also a phosphor that is considered to have a relatively high heat resistance compared to other phosphors, such as Y3Al5O 12 In some cases, rare earth aluminate phosphors having a composition represented by the formula: Y3Al5O 2 :Ce are used. Since this rare earth aluminate phosphor has a relatively low emission intensity on the long wavelength side, for example, at or above 570 nm, when used in a headlamp, it is generally considered that it emits light with a correlated color temperature of about 6000 K. For this reason, when the phosphor contained in the wavelength conversion member is, for example, Y3Al5O 12 It is considered difficult to realize a headlamp that emits light with a correlated color temperature of 5000K or less when only a rare earth aluminate phosphor having a composition represented by formula (1A) is used. In the light emitting device of the first embodiment or the light emitting device of the second embodiment, the phosphor contained in the sintered body used in the wavelength conversion member may contain one of the first phosphor and the second phosphor alone, or may contain two or more of the first phosphor and the second phosphor. The phosphor contained in the sintered body may contain a phosphor having a composition represented by formula (1A) as the first phosphor, and may contain, for example, the following phosphor. (Ba,Sr,Ca)2Si5N8:Eu (La,Y,Gd,Lu)3Si6N 11 :Ce (Ca,Sr)AlSiN3:Eu In addition, as the sintered body used for the wavelength conversion member, a sintered body containing a phosphor having the composition represented by the above formula (1A) and a second nitride phosphor in one sintered body, or a sintered body containing a phosphor having the composition represented by the above formula (1A) and a sintered body containing a second nitride phosphor may be combined in two layers and used. In addition, as the wavelength converter used for the wavelength conversion member, glass is used as the light-transmitting material. For example, glass and a composition formula is M 8 v3 (Si,Al) 12 (O,N) 16 :Eu (M 8 is a lanthanide element other than Li, Mg, Ca, Y, La and Ce, and v3 satisfies 0 < v3 ≦ 2.) A wavelength converter containing an α-sialon phosphor represented by the formula may be used. By using these as the wavelength conversion member, the light-emitting device can emit light with a correlated color temperature of 5000 K or less, and by using this light-emitting device, it is considered that a headlight capable of reducing glare and a vehicle equipped with the same can be provided.

[0067] Light-transmitting material The light-transmitting material includes at least one selected from the group consisting of resin, glass, and inorganic substances. The resin is preferably at least one selected from the group consisting of epoxy resin, silicone resin, phenol resin, and polyimide resin. The inorganic substance includes at least one selected from the group consisting of aluminum oxide and aluminum nitride.

[0068] When the light-transmitting material is a resin, it is preferable that the resin has a Shore A hardness in the range of 30 to 80. The light-transmitting material is preferably a silicone resin, and it is preferable that the silicone resin has a Shore A hardness in the range of 30 to 80. The Shore A hardness of the silicone resin, which is the light-transmitting material, is more preferably in the range of 40 to 75, and even more preferably in the range of 50 to 70. When the light-transmitting material is a resin, the resin expands or contracts due to light or heat. If the light-transmitting material is a silicone resin with a Shore A hardness of 30 to 80, it has excellent toughness and elongation, so that even if the temperature of the environmental atmosphere changes, it flexibly expands and contracts in response to the temperature change, and the wavelength converter is less likely to break or crack, and can emit light with a first luminance ratio Ls / L maintained at 0.9 or less, and has good temperature characteristics. When the light-transmitting material is a silicone resin having a Shore A hardness of 30 or more and 80 or less, it flexibly expands and contracts in response to temperature changes, the wavelength converter is less likely to break or crack, light can be emitted with the second luminance ratio B / A maintained at 0.104 or less, and the temperature characteristics are good. The Shore A hardness of the resin can be measured using a durometer type A in accordance with JIS K6253.

[0069] For example, if a wavelength converter is formed using a resin with a low Shore A hardness of less than 30 as a translucent material, the wavelength converter is soft and sticky, making it difficult to cut when separating individual light-emitting devices from a composite substrate having multiple light-emitting elements. In addition, it may be difficult to transport and package the wavelength converter, resulting in poor mass productivity.

[0070] Therefore, by using a resin having a Shore A hardness of 30 or more and 80 or less as the light-transmitting material, it is possible to obtain a wavelength converter that is less susceptible to breakage or cracks in the wavelength converter or wavelength converting member and has good temperature characteristics.

[0071] Translucent body The wavelength conversion member may include a light-transmitting body. The light-transmitting body may be a plate-shaped body made of a light-transmitting material such as glass or resin. Examples of glass include borosilicate glass and quartz glass. Examples of resin include silicone resin and epoxy resin. The thickness of the light-transmitting body may be any thickness that does not reduce mechanical strength during the manufacturing process and can sufficiently support the wavelength conversion body.

[0072] substrate The substrate is preferably made of an insulating material that is difficult to transmit light from the light emitting element or external light. Examples of the substrate material include ceramics such as aluminum oxide and aluminum nitride, and resins such as phenol resin, epoxy resin, polyimide resin, bismaleimide triazine resin (BT resin), and polyphthalamide (PPA) resin. Ceramics are preferred as a substrate material because of their high heat resistance.

[0073] adhesive layer An adhesive layer is interposed between the light emitting element and the wavelength conversion member, and fixes the light emitting element and the wavelength conversion member. The adhesive constituting the adhesive layer is preferably made of a material that can optically connect the light emitting element and the wavelength conversion member. The material constituting the adhesive layer is preferably at least one resin selected from the group consisting of epoxy resin, silicone resin, phenol resin, and polyimide resin.

[0074] Semiconductor Device Examples of semiconductor elements that are provided in a light-emitting device as necessary include transistors for controlling light-emitting elements and protective elements for preventing the light-emitting elements from being destroyed or their performance from being deteriorated due to application of an excessive voltage, such as Zener diodes.

[0075] Covering material The material of the covering member is preferably an insulating material. More specifically, it may be a phenol resin, an epoxy resin, a bismaleimide triazine resin (BT resin), a polyphthalamide (PPA) resin, or a silicone resin. A colorant, a phosphor, or a filler may be added to the covering member as necessary.

[0076] Conductive material The conductive member may be a bump, and the material of the bump may be Au or an alloy thereof, and other conductive members may be eutectic solder (Au-Sn), Pb-Sn, lead-free solder, or the like.

[0077] Method for manufacturing a light emitting device An example of a method for manufacturing a light emitting device will be described. For details, refer to, for example, the disclosures of JP 2014-112635 A or JP 2017-117912 A. The method for manufacturing a light emitting device preferably includes a step of arranging a light emitting element, a step of arranging a semiconductor element as necessary, a step of forming a wavelength conversion member including a wavelength converter, a step of bonding the light emitting element and the wavelength conversion member, and a step of forming a covering member.

[0078] Light emitting element arrangement process The light emitting element is disposed on the substrate, and the light emitting element and the semiconductor element are mounted on the substrate by, for example, flip-chip bonding.

[0079] Forming process of wavelength conversion member including wavelength conversion body In the step of forming a wavelength conversion member including a wavelength converter, the wavelength conversion member may be obtained by forming a plate-shaped, sheet-shaped or layer-shaped wavelength conversion member on one surface of a light-transmitting body by a printing method, an adhesive method, a compression molding method or an electrodeposition method. For example, the printing method can print a composition for a wavelength conversion member including a phosphor and a resin serving as a light-transmitting material on one surface of the light-transmitting body to form a wavelength conversion member including a wavelength converter.

[0080] Wavelength converter composition The composition for wavelength converter constituting the wavelength converter or wavelength conversion member includes a light-transmitting material, a first phosphor, and a second phosphor, and may also include a solvent. When the composition for wavelength converter includes a solvent, the viscosity of the composition for wavelength converter decreases, and when the composition for wavelength converter is cured, even if the total amount of phosphors relative to the light-transmitting material is small, the density of the first phosphor and the second phosphor increases in the direction of gravity, and a wavelength converter or wavelength conversion member having different filling rates of the first phosphor and the second phosphor in the wavelength converter or wavelength conversion member can be manufactured. The wavelength converter or wavelength conversion member is less likely to break or crack due to the presence of a portion with a high filling rate of the first phosphor and the second phosphor. By arranging the high-concentration layer side having a high filling rate of the first and second phosphors of the wavelength converter on the light-emitting element side, even when a high-output light-emitting element is used, heat generated from the light-emitting element can be dissipated through the first and second phosphors in the wavelength converter, cracks and breaks in the resin constituting the wavelength converter are suppressed, and light can be emitted with a first luminance ratio Ls / L maintained at 0.9 or less, and the temperature characteristics are good. By arranging the high-concentration layer side having a high filling rate of the first and second phosphors of the wavelength converter on the light-emitting element side, even when a high-output light-emitting element is used, heat generated from the light-emitting element can be dissipated through the first and second phosphors in the wavelength converter, cracks and breaks in the resin constituting the wavelength converter are suppressed, and light can be emitted with a second luminance ratio B / A maintained at 0.104 or less, and the temperature characteristics are good.

[0081] In consideration of the solubility in the light-transmitting resin and volatility, the solvent preferably has a boiling point under standard pressure (0.101 MPa) in the range of 150° C. to 320° C., more preferably in the range of 170° C. to 305° C., even more preferably in the range of 180° C. to 300° C., and particularly preferably in the range of 190° C. to 290° C. When the solvent having a boiling point under standard pressure in the range of 150° C. to 320° C. is contained in the wavelength converter composition, the viscosity of the wavelength converter composition is reduced, and when the composition is cured, a high-concentration layer having a high filling rate of phosphors including the first phosphor and the second phosphor in the gravity direction and a low-concentration layer having a low filling rate of the first phosphor and the second phosphor can be formed.

[0082] The viscosity of the wavelength converter composition at 25°C and 1 rpm as measured with an E-type viscometer is preferably in the range of 5 mPa·s or more and 400 mPa·s or less, more preferably in the range of 6 mPa·s or more and 300 mPa·s or less, and even more preferably in the range of 8 mPa·s or more and 250 mPa·s or less.

[0083] When the light-transmitting material is a silicone resin, and the composition for the wavelength converter contains a total amount of phosphor in the range of 50 parts by mass or more and 500 parts by mass or less per 100 parts by mass of the light-transmitting material, the content of the solvent is preferably in the range of 1 part by mass or more and 50 parts by mass or less, more preferably in the range of 2 parts by mass or more and 40 parts by mass or less, and even more preferably in the range of 3 parts by mass or more and 30 parts by mass or less, per 100 parts by mass of the light-transmitting material.

[0084] The solvent is an organic compound liquid, and a part of it evaporates (volatilizes) at room temperature. For example, by heating at 180° C. or higher, the solvent remaining in the composition for wavelength converter can be volatilized, and the composition for wavelength converter can be cured to form a wavelength converter or a wavelength conversion member. Examples of the solvent include hydrocarbon-based solvents, ketone-based solvents, alcohol-based solvents, aldehyde-based solvents, glycol-based solvents, ether-based solvents, ester-based solvents, glycol ether-based solvents, and glycol ester-based solvents. Examples of the hydrocarbon-based solvents include hexane, xylene, heptane, decane, dodecane, and tridecane. Examples of the ketone-based solvents include acetone and methyl ethyl ketone. Examples of the alcohol-based solvents include methyl alcohol, ethyl alcohol, and isopropyl alcohol. Examples of the aldehyde-based solvents include nonanal and decanal. Examples of the glycol-based solvents include triethylene glycol. Examples of the ether-based solvents include diethyl ether. Examples of the ester-based solvents include methyl acetate and ethyl acetate. Examples of the glycol ether-based solvents include propylene glycol monomethyl ether. Examples of glycol ester solvents include ethylene glycol monoethyl ether acetate. The solvent is preferably at least one selected from the group consisting of hexane, xylene, heptane, acetone, ethanol, isopropyl alcohol, decane, dodecane, tridecane, tetradecane, pentadecane, hexadecane, nonanal, decanal, and triethylene glycol. The solvent is more preferably at least one selected from the group consisting of dodecane, tetradecane, pentadecane, hexadecane, and tridecane. The solvent may be used alone or in combination of two or more.

[0085] Wavelength conversion body or wavelength conversion member When the composition for wavelength converter contains a solvent, a wavelength converter or wavelength conversion member can be formed in which a high-concentration layer with a high filling rate of the first phosphor and the second phosphor and a low-concentration layer with a low filling rate of the first phosphor and the second phosphor are separated in the direction of gravity when the composition for wavelength converter is cured. In this specification, a high-concentration layer with a high filling rate of the phosphor and a low-concentration layer with a low filling rate of the phosphor can be confirmed in the thickness direction of the cross section of the wavelength converter. As described above, the filling rate of the phosphor can be measured by observing the cross section of the wavelength converter or the cross section of the wavelength conversion member with an SEM and measuring the filling rate of the phosphor from the area ratio of the resin to the phosphor in the cross section. The boundary between one layer and another layer may not be a straight line but may have an unevenness.

[0086] Bonding process between light emitting element and wavelength conversion material In the bonding process of the light emitting element and the wavelength conversion member, the wavelength conversion member is placed opposite to the light emitting surface of the light emitting element, and the wavelength conversion member is bonded to the light emitting element by an adhesive layer. When the wavelength conversion member includes a wavelength converter and a light transmitting body, and the wavelength conversion member includes a high-concentration layer with a high phosphor filling rate and a low-concentration layer with a low phosphor filling rate, it is preferable to place the high-concentration layer with a high phosphor filling rate on the light emitting element side and bond the wavelength conversion member to the light emitting element. The phosphor containing the first phosphor and the second phosphor has a higher thermal conductivity than resin, and by placing the high-concentration layer with a high phosphor filling rate of the wavelength converter on the light emitting element side and bonding the wavelength conversion member, heat dissipation is improved, the wavelength conversion member is less likely to break or crack, and the temperature characteristics are good.

[0087] Forming process of the covering member In the step of forming the covering member, the side surfaces of the light emitting element and the wavelength conversion member are covered with a composition for the covering member. This covering member is for reflecting light emitted from the light emitting element, and when the light emitting device also includes a semiconductor element, it is preferable to form the covering member so that the semiconductor element is embedded in the covering member. The method may include a step of singulating a composite substrate having a plurality of light emitting elements and semiconductor elements on one substrate into individual light emitting devices.

[0088] For example, if a wavelength converter is formed using a resin with a low Shore A hardness of less than 30 as a translucent material, the wavelength converter is soft and sticky, making it difficult to cut when separating individual light-emitting devices from a composite substrate having multiple light-emitting elements. In addition, it may be difficult to transport and package the wavelength converter, resulting in poor mass productivity.

[0089] Therefore, by using a resin having a Shore A hardness of 30 or more and 80 or less as the light-transmitting material, it is possible to obtain a wavelength converter that is less susceptible to breakage or cracks in the wavelength converter or wavelength converting member and has good temperature characteristics.

[0090] Headlights The light emitting device may be disposed on a support substrate of a light source unit for a headlight and used as a headlight mounted on a vehicle. The light source unit for a headlight may be, for example, a light source unit disclosed in Japanese Patent Application Laid-Open No. 2003-317513. The light source unit includes, for example, a reflector, a projection lens, and a support substrate on which the light emitting device is disposed. The light source unit for a headlight may be controlled to be turned on by a vehicle lamp system such as that disclosed in Japanese Patent Application Laid-Open No. 8-67199. The light emitting device may be used as a light source for a headlight used in a turn signal lamp such as that disclosed in Japanese Patent Application Laid-Open No. 2005-123165. FIG. 4 is a horizontal cross-sectional view of the headlight. FIG. 5 is a front view of the headlight. The headlight 200 shown in FIG. 4 and FIG. 5 is provided, for example, on the right side of the front of the vehicle. The headlamp 200 includes a lamp body 24, an outer lens 22, a plurality of substrates 32, a plurality of light emitting devices 100, an optical filter 26, and a light guiding member 34. The lamp body 24 and the outer lens 22 form a lamp chamber of the headlamp 200, and hold the plurality of substrates 32 and the plurality of light emitting devices 100 in this lamp chamber while keeping them waterproof. The lamp body 24 is formed, for example, from a resin, so as to cover the plurality of substrates 32 and the plurality of light emitting devices 100 from the rear of the vehicle. The optical filter 26 is fixed to the lamp body 24 by a plurality of screws 28. Each of the plurality of light emitting devices 100 lights up in response to power received from the lighting control unit 12 via the substrate 32.

[0091] The headlamp may include a plurality of first lamp units in which one light emitting device is arranged in one light source unit, as disclosed in, for example, JP 2003-317513 A. The headlamp may include a second lamp unit in which a plurality of light emitting devices are arranged in one light source unit in which a plurality of reflectors, a plurality of projection lenses, and a plurality of support substrates are integrally formed, as disclosed in, for example, JP 2005-141917 A. The headlamp may include two or more types of light emitting devices having different first luminance ratios Ls / L. The two or more types of light emitting devices having different first luminance ratios Ls / L may each be arranged in one light source unit. The two or more types of light emitting devices having different first luminance ratios Ls / L may each be arranged in one light source unit. The headlamp may include two or more types of light emitting devices having different second luminance ratios B / A. The two or more types of light emitting devices having different second luminance ratios B / A may each be arranged in one light source unit. The two or more types of light emitting devices having different second luminance ratios B / A may be arranged in one light source unit.

[0092] The headlamp may include two or more types of light-emitting devices, with the above-mentioned light-emitting device emitting light having a first luminance ratio Ls / L of 0.9 or less being the first light-emitting device, and a light-emitting device emitting light having a first luminance ratio Ls / L of more than 0.9 being the second light-emitting device.

[0093] The headlamp may include two or more types of light-emitting devices, with the above-mentioned light-emitting device emitting light having a second luminance ratio B / A of 0.104 or less as a first light-emitting device, and a light-emitting device emitting light having a second luminance ratio B / A of more than 0.104 as a second light-emitting device.

[0094] The second light emitting device may be a light emitting device that emits light with a first luminance ratio Ls / L exceeding 0.9 or a light emitting device that emits light with a second luminance ratio B / A exceeding 0.104. The second light emitting device may be, for example, in the same form as the first light emitting device shown in Fig. 3A and Fig. 3B. The second light emitting device may be, for example, a light emitting device that includes a light emitting element having an emission peak wavelength in the range of 400 nm to 490 nm and a first phosphor having an emission peak wavelength in the range of 480 nm to less than 580 nm, and does not include a second phosphor. The first phosphor may be the same phosphor as the first phosphor described above. The second light-emitting device includes a light-emitting element having an emission peak wavelength in the range of 400 nm or more and 490 nm or less, and a rare earth aluminate phosphor having a composition represented by formula (1A) as a first phosphor, and does not include a second phosphor, and emits light with a first luminance ratio Ls / L exceeding 0.9 or a second luminance ratio B / A exceeding 0.104 and a correlated color temperature in the range of 5000 K or more and 6500 K or less.

[0095] vehicle The vehicle of the third embodiment may be a vehicle in which the above-mentioned light emitting device or headlamp may be mounted. Examples of the vehicle in which the above-mentioned light emitting device or headlamp may be mounted include road vehicles such as motorcycles and four-wheeled automobiles, railway vehicles, and vehicles used in tractor-based vehicle-based construction machines such as land leveling, transporting, and loading machines, or excavator-based vehicle-based construction machines such as excavation machines.

[0096] Embodiments according to the present invention include the following light-emitting device, headlamp, and vehicle.

[0097] [Section 1] A light emitting element having an emission peak wavelength in the range of 400 nm to 490 nm, A wavelength conversion member including a first phosphor having an emission peak wavelength in the range of 480 nm or more and less than 580 nm, and a second phosphor having an emission peak wavelength in the range of 580 nm or more and 680 nm or less and having a composition different from that of the first phosphor; A light emitting device comprising: The light emitting device emits light having a first luminance ratio Ls / L of 0.9 or less, which is a ratio of a first effective radiance Ls of light emitted by the light emitting device in a range of 380 nm to 780 nm inclusive, taking into account the standard luminous efficiency curve for human photopic vision defined by the CIE (International Commission on Illumination), to a luminance L of light emitted by the light emitting device in a range of 380 nm to 780 nm inclusive, taking into account the standard luminous efficiency curve for human photopic vision and the spectral sensitivity of human S-cones, and which is derived from the following formula (1): A light emitting device, wherein the first phosphor comprises a rare earth aluminate phosphor having a composition represented by the following formula (1A): TIFF2024058077000011.tif39125 (In formula (1), S(λ) is the spectral radiance of the light emitted by the light-emitting device, V(λ) is the standard luminous efficiency curve for human photopic vision defined by the CIE (International Commission on Illumination), and Gs(λ) is the spectral sensitivity of human S-cones in the wavelength range of λnm from 380 nm to 550 nm.) Ln 1 3-e Ce e (Al 1-a Ga a )5O 12 (1A) (In formula (1A), Ln 1 is at least one element selected from the group consisting of Y, Gd, Tb and Lu, and a and e satisfy 0≦a≦0.5 and 0.019≦e≦0.2. [Section 2] Item 2. The light emitting device according to item 1, which emits light having a correlated color temperature of 1800K or more and 5000K or less. [Section 3] 3. The light emitting device according to item 1 or 2, wherein the first phosphor has an emission spectrum full width at half maximum in the range of 90 nm to 125 nm. [Section 4] Item 4. The light emitting device according to any one of items 1 to 3, wherein the second phosphor has an emission spectrum full width at half maximum in the range of 3 nm to 15 nm, or an emission spectrum full width at half maximum in the range of 60 nm to 120 nm. [Section 5] The light-emitting device according to any one of items 1 to 4, wherein the average particle diameter of the rare earth aluminate phosphor having the composition represented by the formula (1A) is in the range of 15 μm or more and 40 μm or less as measured by the Fisher sub-sieve sizer method. [Item 6] The light-emitting device according to any one of items 1 to 5, wherein the first phosphor contains a rare earth aluminate phosphor having the composition represented by the formula (1A), and further contains a first nitride phosphor having the composition represented by the following formula (1B). La w Ln 2 x Ce z Si6N y (1B) (In the formula (1B), Ln 2 essentially contains at least one selected from the group consisting of Y and Gd, and may contain at least one selected from the group consisting of Sc and Lu. When the Ln 2 element is 100 mol%, the total of Y and Gd contained in Ln 2 is 90 mol% or more, and w, x, y, and z satisfy 1.2 ≤ w ≤ 2.2, 0.5 ≤ x ≤ 1.2, 10 ≤ y ≤ 12, 0.5 ≤ z ≤ 1.2, 1.80 < w + x < 2.40, 2.9 ≤ w + x + z ≤ 3.1.) [Item 7] The light-emitting device according to any one of items 1 to 6, wherein the second phosphor contains at least one selected from the group consisting of a second nitride phosphor having the composition represented by the following formula (2A), a third nitride phosphor having the composition represented by the following formula (2B), a fluoride phosphor having the composition represented by the following formula (2C), a fluoride phosphor having the composition represented by the following formula (2C') which has a different composition from the formula (2C), and an α-sialon phosphor having the composition represented by the following formula (2G). M 1 2Si5N8:Eu (2A) (In the formula (2A), M 1 is an alkaline earth metal element containing at least one selected from the group consisting of Ca, Sr, and Ba.) Sr q Ca s Alt Si u N v :Eu (2B) (In formula (2B), q, s, t, u, and v satisfy 0 ≦ q < 1, 0 < s ≦ 1, q + s ≦ 1, 0.9 ≦ t ≦ 1.1, 0.9 ≦ u ≦ 1.1, and 2.5 ≦ v ≦ 3.5, respectively.) A c [M 2 1-b Mn 4+ b F d (2C) (In formula (2C), A includes at least one selected from the group consisting of K + , Li + , Na + , Rb + , Cs + , and NH4 + . M 2 includes at least one element selected from the group consisting of Group 4 elements and Group 14 elements. b satisfies 0 < b < 0.2, and c is the absolute value of the charge of the [M 2 1-b Mn 4+ b F d ion, and d satisfies 5 < d < 7.) A’ c’ [M 2 ’ 1-b’ Mn 4+ b’ F d’ (2C’) (In formula (2C’), A’ includes at least one selected from the group consisting of K + , Li + , Na + , Rb + , Cs + , and NH4 + . M 2 ’ includes at least one element selected from the group consisting of Group 4 elements, Group 13 elements, and Group 14 elements. b’ satisfies 0 < b’ < 0.2, and c’ is the absolute value of the charge of the [M 2 ’ 1-b’ Mn 4+ b’ F d’ ion, and d’ satisfies 5 < d’ < 7.) M 8 v3 Si 12-(w3+x3) Al w3+x3 O x3 N 16-x3 :Eu (2G) (In formula (2G), M 8 includes at least one element selected from the group consisting of Li, Mg, Ca, Sr, Y, and lanthanoid elements (excluding La and Ce), and v3, w3, and x3 satisfy 0 < v3 ≤ 2.0, 2.0 ≤ w3 ≤ 6.0, and 0 ≤ x3 ≤ 1.0, respectively.) [Item 8] The light-emitting device according to any one of Items 1 to 7, wherein the wavelength conversion member includes a wavelength converter including the first phosphor and the second phosphor and a light-transmitting material, and the total amount of the first phosphor and the second phosphor is in the range of 50 parts by mass or more and 500 parts by mass or less with respect to 100 parts by mass of the light-transmitting material in the wavelength converter. [Item 9] The wavelength conversion member includes a wavelength converter including the first phosphor and the second phosphor and a light-transmitting material, the wavelength converter includes a high-concentration layer having a high filling rate of the first phosphor and the second phosphor and a low-concentration layer having a low filling rate of the first phosphor and the second phosphor, The light-emitting device according to any one of Items 1 to 8, wherein the high-concentration layer is disposed on the side of the light-emitting element. [Item 10] A headlamp including the light-emitting device according to any one of Items 1 to 9. [Item 11] The headlamp according to Item 10, including two or more light-emitting devices having different values of the first luminance ratio Ls / L. [Item 12] 10. A headlamp comprising two or more types of light-emitting devices, the first light-emitting device including the light-emitting device according to any one of items 1 to 9, and a second light-emitting device emitting light such that a first luminance ratio Ls / L, which is a ratio of a first effective radiance of light emitted by the light-emitting device having a wavelength of 380 nm or more and 780 nm or less in consideration of the standard relative luminous efficiency curve for human photopic vision defined by the CIE (International Commission on Illumination), to a first luminance ratio Ls / L derived from the following formula (1) exceeds 0.9: TIFF2024058077000012.tif39125(In formula (1), S(λ) is the spectral radiance of the light emitted by the light-emitting device, V(λ) is the standard luminous efficiency curve for human photopic vision defined by the CIE (International Commission on Illumination), and Gs(λ) is the spectral sensitivity of human S-cones in the wavelength range λnm of 380 nm to 550 nm.) [Section 13] A light emitting element having an emission peak wavelength in the range of 400 nm to 490 nm, A wavelength conversion member including a first phosphor having an emission peak wavelength in the range of 480 nm or more and less than 580 nm, and a second phosphor having an emission peak wavelength in the range of 580 nm or more and 680 nm or less and having a composition different from that of the first phosphor; A light emitting device comprising: The light emitting device emits light having a second luminance ratio B / A of 0.104 or less, which is a ratio of a second effective radiance B of light emitted by the light emitting device in the range of 300 nm to 800 nm inclusive, taking into consideration a scattering intensity curve for wavelength when the scattering intensity of Rayleigh scattering at a wavelength of 300 nm is set to 1, to a radiance A of light emitted by the light emitting device in the range of 300 nm to 800 nm inclusive, and which is derived from the following formula (2): A light emitting device, wherein the first phosphor comprises a rare earth aluminate phosphor having a composition represented by the following formula (1A): TIFF2024058077000013.tif40103 (In formula (2), S(λ) is the spectral radiance of the light emitted by the light emitting device, and Dc(λ) is the scattering intensity curve for Rayleigh scattering with the scattering intensity of Rayleigh scattering at a wavelength of 300 nm set to 1.) Ln 1 3-e Ce e (Al 1-a Ga a )5O 12 (1A) (In formula (1A), Ln 1 is at least one element selected from the group consisting of Y, Gd, Tb, and Lu, and a and e satisfy 0 ≦ a ≦ 0.5 and 0.019 ≦ e ≦ 0.2.) [Item 14] The light-emitting device according to Item 13, which emits light having a correlated color temperature of 1800 K or higher and 5000 K or lower. [Item 15] The light-emitting device according to Item 13 or 14, wherein the first phosphor has a full width at half maximum of the emission spectrum in the range of 90 nm or more and 125 nm or less. [Item 16] The light-emitting device according to any one of Items 13 to 15, wherein the second phosphor has a full width at half maximum of the emission spectrum in the range of 3 nm or more and 15 nm or less, or has a full width at half maximum of the emission spectrum in the range of 60 nm or more and 120 nm or less. [Item 17] The light-emitting device according to any one of Items 13 to 16, wherein the first phosphor contains a rare earth aluminate phosphor having a composition represented by the formula (1A), and further contains a first nitride phosphor having a composition represented by the following formula (1B). La w Ln 2 x Ce z Si6N y : (1B) (In formula (II), Ln 2 essentially contains at least one selected from the group consisting of Y and Gd, and may contain at least one selected from the group consisting of Sc and Lu. When the Ln 2 element contained in 1 mole of the composition is taken as 100 mol%, the total of Y and Gd contained in Ln 2 is 90 mol% or more, and w, x, y, and z satisfy 1.2 ≦ w ≦ 2.2, 0.5 ≦ x ≦ 1.2, 10 ≦ y ≦ 12, 0.5 ≦ z ≦ 1.2, 1.80 < w + x < 2.40, and 2.9 ≦ w + x + z ≦ 3.1.) [Item 18] The light-emitting device according to any one of Items 13 to 17, wherein the second phosphor contains at least one selected from the group consisting of a second nitride phosphor having a composition represented by the following formula (2A), a third nitride phosphor having a composition represented by the following formula (2B), a fluoride phosphor having a composition represented by the following formula (2C), a fluoride phosphor having a composition represented by the following formula (2C') which is different in composition from the following formula (2C), and an α-sialon phosphor having a composition represented by the following formula (2G). M 1 2Si5N8:Eu (2A) (In formula (2A), M 1 is an alkaline earth metal element containing at least one selected from the group consisting of Ca, Sr, and Ba.) Sr q Ca s Al t Si u N v :Eu (2B) (In formula (2B), q, s, t, u, and v each satisfy 0 ≦ q < 1, 0 < s ≦ 1, q + s ≦ 1, 0.9 ≦ t ≦ 1.1, 0.9 ≦ u ≦ 1.1, and 2.5 ≦ v ≦ 3.5.) A c [M 2 1-b Mn 4+ b F d (2C) (In formula (2C), A is at least one selected from the group consisting of K + , Li + , Na + , Rb + , Cs + and NH4 + , M 2 contains at least one element selected from the group consisting of Group 4 elements and Group 14 elements, b satisfies 0 < b < 0.2, and c is the absolute value of the charge of the [M 2 1-b Mn 4+ b F d ion, and d satisfies 5 < d < 7.) A’ c’ [M2 ’ 1-b’ Mn 4+ b’ F d’ (2C’) (In formula (2C’), A’ is K + , Li + , Na + , Rb + , Cs + and NH4 + and includes at least one selected from the group consisting of, M 2 ’ includes at least one element selected from the group consisting of Group 4 elements, Group 13 elements and Group 14 elements, b’ satisfies 0 < b’ < 0.2, and c’ is [M 2 ’ 1-b’ Mn 4+ b’ F d’ is the absolute value of the charge of the ion, and d’ satisfies 5 < d’ < 7.) M 8 v3 Si 12-(w3+x3) Al w3+x3 O x3 N 16-x3 :Eu (2G) (In formula (2G), M 8 includes at least one element selected from the group consisting of Li, Mg, Ca, Sr, Y and lanthanoid elements (excluding La and Ce), and v3, w3 and x3 each satisfy 0 < v3 ≤ 2.0, 2.0 ≤ w3 ≤ 6.0, 0 ≤ x3 ≤ 1.0.) [Item 19] The light-emitting device according to any one of Items 13 to 18, wherein the average particle diameter of the rare-earth aluminate phosphor having the composition represented by the formula (1A) is in the range of 15 μm or more and 40 μm or less as measured by the Fischer sub-sieve sizer method. [Item 20] The wavelength conversion member includes a wavelength converter including the first phosphor and the second phosphor and a light-transmitting material, and the total amount of the first phosphor and the second phosphor is in the range of 50 parts by mass or more and 500 parts by mass or less with respect to 100 parts by mass of the light-transmitting material in the wavelength converter. The light-emitting device according to any one of Items 13 to 19. [Item 21] the wavelength conversion member includes a wavelength conversion body including the first phosphor and the second phosphor, and a light-transmitting material; the wavelength converter comprises a high-concentration layer having a high filling rate of the first phosphor and the second phosphor, and a low-concentration layer having a low filling rate of the first phosphor and the second phosphor, Item 21. The light-emitting device according to any one of items 13 to 20, wherein the high-concentration layer is disposed on the side of the light-emitting element. [Section 22] 22. A headlamp comprising the light emitting device according to any one of items 13 to 21. [Section 23] Item 23. The headlamp according to item 22, comprising two or more types of light emitting devices each having a different value of the second luminance ratio B / A. [Section 24] A first light emitting device including the light emitting device according to any one of items 13 to 21; A headlamp comprising two or more types of second light-emitting devices that emit light with a second luminance ratio B / A derived from the following formula (2) exceeding 0.104, the second luminance ratio being the ratio of a second effective radiance B of light emitted by the light-emitting device in the range of 300 nm or more and 800 nm or less, taking into account the scattering intensity curve for wavelength when the scattering intensity of Rayleigh scattering at a wavelength of 300 nm is set to 1, to a radiance A of light emitted by the light-emitting device in the range of 300 nm or more and 800 nm or less. TIFF2024058077000014.tif40103 (In formula (2), S(λ) is the spectral radiance of the light emitted by the light emitting device, and Dc(λ) is the scattering intensity curve for Rayleigh scattering with the scattering intensity of Rayleigh scattering at a wavelength of 300 nm set to 1.) [Section 25] A vehicle comprising the light emitting device according to any one of items 1 to 9 and 13 to 21. [Section 26] A vehicle equipped with the headlamp according to any one of items 10 to 12 and 22 to 24. EXAMPLES

[0098] The present invention will be described in more detail below with reference to examples, but the present invention is not limited to these examples.

[0099] In the light emitting devices of the respective Examples and Comparative Examples, the following first and second phosphors were used.

[0100] First phosphor The first phosphor has a composition represented by the formula (1A), and Ln 1 The rare earth aluminate phosphors YAG-1, YAG-2, YAG-3, YAG-4, and YAG-5 were prepared, each of which has a composition not included in the formula (1A) and a molar ratio of Ce contained in the composition (variable e in the formula (1A)) shown in Table 1. 1 YAG-6 was prepared, in which the molar ratio of Ce contained in the composition is 0.018 and the first phosphor is Y. As shown in Table 1, these first phosphors have different average particle sizes measured by the FSSS method, CIE chromaticity coordinates (x, y), emission peak wavelengths, and full widths at half maximum. In this specification, the symbol "-" in Table 1 indicates that there is no corresponding item or value.

[0101] Second phosphor As the second phosphor, BSESN-1, which is a second nitride phosphor having a composition represented by the above formula (2A), was prepared. The second phosphor has an average particle size, CIE chromaticity coordinates (x, y), emission peak wavelength, and full width at half maximum measured by the FSSS method, as shown in Table 1.

[0102] Phosphor emission spectrum Each phosphor was irradiated with light having an excitation wavelength of 450 nm using a quantum efficiency measuring device (QE-2000, manufactured by Otsuka Electronics Co., Ltd.) to measure the emission spectrum at room temperature (approximately 25°C). From each emission spectrum, the x and y values ​​in the CIE1931 chromaticity coordinates, the emission peak wavelength, and the full width at half maximum were measured.

[0103] Average particle size of phosphor The average particle size of each phosphor was measured by the FSSS method using a Fisher Sub-Sieve Sizer Model 95 (manufactured by Fisher Scientific). 3 A volume of sample phosphor is measured and packed into a special tubular container. Dry air is then passed through the container at a constant pressure, and the specific surface area is read from the pressure difference and converted into the average particle size (Fisher Sub-Sieve Sizer's No.).

[0104] [Table 1]

[0105] Examples 1 to 6 A light emitting device having the configuration shown in FIGS. 3A and 3B was manufactured. In the process of arranging the light-emitting element, a ceramic substrate made of aluminum nitride was used as the substrate. The light-emitting element used was a light-emitting element in which a nitride-based semiconductor layer having an emission peak wavelength of 450 nm was laminated. The size of the light-emitting element was a roughly square shape of about 1.0 mm square in plan view, and the thickness was about 0.11 mm. The light-emitting element was arranged so that the light-emitting surface was on the substrate side, and flip-chip mounted with bumps using a conductive member made of Au. In addition, a semiconductor element was flip-chip mounted with a gap between the light-emitting element and bumps using a conductive member made of Au.

[0106] Silicone resin a (Shore A hardness 70) was used as the light-transmitting material. In the process of forming the wavelength conversion member including the wavelength converter, the first phosphor and the second phosphor were used in the ratio shown in Table 2 relative to 100 parts by mass of silicone resin a as the light-transmitting material. In Table 2, the total amount of phosphor indicates the total amount of the first phosphor and the second phosphor relative to 100 parts by mass of silicone resin a. In addition, in Table 2, the mass ratio (mass%) of the first phosphor and the mass ratio (mass%) of the second phosphor indicate the mass ratio of the first phosphor and the mass ratio of the second phosphor when the total content of the first phosphor and the second phosphor is 100% by mass. The content of the first phosphor or the content of the second phosphor contained in the light-emitting device can be calculated by dividing the product of the total amount (mass parts) of the first phosphor and the second phosphor and the mass ratio (mass%) of the first phosphor and the second phosphor by 100. A light-transmitting body was prepared as a light-transmitting body, which was made of borosilicate glass, had a planar shape of approximately 1.15 mm square, which was approximately 0.15 mm larger in length and width than the planar shape of the light-emitting element, and had a thickness of approximately 0.10 mm. A composition for a wavelength converter was printed on one surface of the approximately square shape of the light-transmitting body by a printing method, and the composition for a wavelength converter was cured by heating at 180°C for 2 hours to form a layered wavelength converter with a thickness of approximately 80 μm, thereby forming a wavelength conversion member in which a layered or plate-shaped wavelength converter and a light-transmitting body are integrated. In this specification, the Shore A hardness of the silicone resin was measured using a durometer type A (product name: GS-709G, manufactured by TECLOCK Co., Ltd.) in accordance with JIS K6253.

[0107] In the process of bonding the light-emitting element and the wavelength conversion member, one surface of the wavelength conversion member, which has a planar shape of approximately 1.15 mm square, and one surface of the light-emitting element, which has a planar shape of approximately 1.0 mm square, were bonded together using an adhesive containing silicone resin to form an adhesive layer between the light-emitting element and the wavelength conversion member.

[0108] In the step of forming a covering member, a composition for a covering member was prepared, which contained dimethyl silicone resin and titanium oxide particles, with 30 parts by mass of titanium oxide particles per 100 parts by mass of dimethyl silicone resin. The side surfaces of the light emitting element and the wavelength converter including the wavelength conversion member and the light transmitting body arranged on the substrate were covered with the composition for a covering member, and the composition for a covering member was filled so that the semiconductor element was completely embedded in the composition for a covering member, and the composition for a covering member was cured to form a covering member, thereby forming a resin package, and a light emitting device was manufactured.

[0109] Comparative Example 1 A light-emitting device was manufactured in the same manner as in Example 1, except that YAG-6 having a composition not included in formula (1A) was used as the first phosphor, and the first phosphor and second phosphor were used in the compositions shown in Table 2.

[0110] The following measurements were carried out for each light-emitting device. The results are shown in Table 2.

[0111] Emission spectrum of the light-emitting device, chromaticity coordinates (x, y), correlated color temperature (K) The emission spectrum of each light-emitting device was measured at room temperature (25°C ± 5°C) using an optical measurement system combining a spectrophotometer (PMA-11, manufactured by Hamamatsu Photonics K.K.) and an integrating sphere. From the emission spectrum of each light-emitting device, the x and y values ​​in the CIE1931 chromaticity coordinates and the correlated color temperature (K) in accordance with JIS Z8725 were measured. Figure 6 shows the emission spectrum of the light-emitting device according to Example 1 when the maximum emission intensity is set to 1.

[0112] First luminance ratio Ls / L The emission spectrum S(λ) measured for each light-emitting device, the spectral sensitivity Gs(λ) of the human S cone obtained from Figure 1A, and the standard relative luminous efficiency curve V(λ) of human photopic vision defined by the CIE obtained from Figure 1B were input into the above formula (1), and the first luminance ratio Ls / L of the emission of each light-emitting device was measured.

[0113] Second luminance ratio B / A The emission spectrum S(λ) measured for each light-emitting device and the scattering intensity curve Dc(λ) obtained from FIG. 2 were inserted into the above formula (2) to measure the second luminance ratio B / A of the emission from each light-emitting device.

[0114] Relative luminous flux (%) The luminous flux of each light emitting device was measured using a total luminous flux measuring device using an integrating sphere. The luminous flux of the light emitting device of Comparative Example 1 was set as 100%, and the relative luminous flux of each light emitting device other than Comparative Example 1 was calculated.

[0115] [Table 2]

[0116] The light emitting devices according to Examples 1 to 6 emitted light having a correlated color temperature of 1800 K or more and 5000 K or less and a first luminance ratio Ls / L of 0.9 or less. The light emitting devices according to Examples 1 to 6 emitted light with reduced glare.

[0117] The light emitting devices according to Examples 1 to 6 emitted light having a second luminance ratio B / A of 0.104 or less. The light emitting devices according to Examples 1 to 6 suppressed scattering of light and emitted light that reached a relatively long distance.

[0118] The light emitting devices of Examples 1 to 6 include a first phosphor having a composition represented by formula (1A), in which the variable e representing the molar ratio of Ce, an activating element, satisfies the range of 0.019 to 0.2 (0.019≦e≦0.2), more specifically, the range is 0.025 to 0.112, and the content of the first phosphor contained in the light emitting device (the amount obtained by dividing the product of the total amount of phosphor and the mass proportion of the first phosphor by 100) can be made smaller than that of a first phosphor having a composition not included in the composition formula represented by formula (1A). Furthermore, the light emitting devices according to Examples 1 to 6 include a first phosphor having a composition represented by formula (1A), in which the variable e representing the molar ratio of Ce, an activator element, satisfies the range of 0.019 or more and 0.2 or less (0.019≦e≦0.2). Therefore, the total amount of phosphor contained in the wavelength conversion member can be made smaller than that of the wavelength conversion member used in the light emitting device according to Comparative Example 1. Even when the total amount of phosphor is small, light is emitted that has a color tone within the desired range of the CIE chromaticity coordinates, a first luminance ratio Ls / L is 0.9 or less, and a second luminance ratio B / A is 0.104 or less.

[0119] Reliability evaluation test, quantification of peeling rate A reliability evaluation was performed on each light emitting device. The results are shown in Table 3. The reliability evaluation was performed by repeatedly turning the light emitting device on and off for 30 minutes at a current of 1200 mA for 700 hours in an environmental tester at 85°C and relative humidity of 85%. After the reliability evaluation test, the wavelength conversion member of the light emitting device was observed under a microscope, and the durability was evaluated by quantifying the rate of peeling that occurred between the wavelength converter and the translucent body. In FIG. 3B, the rate of peeling that occurred between the wavelength converter 41 and the translucent body 42 of the wavelength conversion member 40 was quantified. The peeling ratio was quantified using ImageJ, a public domain image analysis processing software developed by the National Institutes of Health, which is an open source software. A photograph of the light-emitting device taken from the transparent body side with a microscope was cut out so that only the transparent body surface was shown, and the color photograph of the transparent body was separated into the three primary colors RGB, and only G was extracted from the three primary colors RGB. This is because G tends to have a clear and distinct light contrast (light and dark). The contrast of the photograph in which only G was extracted from the color photograph of the transparent body of the light-emitting device was adjusted to emphasize the peeling part that occurred between the wavelength conversion body and the transparent body, and the peeling part was binarized, and the ratio of the total area of ​​the peeling part on the transparent body surface to the area of ​​the transparent body surface (peeled surface / transparent body surface (%)) was calculated as the peeling ratio. The calculated peeling ratio values ​​are shown in Table 3. Table 3 also shows the type of first phosphor represented by the above formula (1A) contained in the wavelength conversion member of each light-emitting device, and the molar ratio of Ce contained in the first phosphor (variable e in the above formula (1A)). Fig. 8 shows a photograph in which the light-transmitting surface of the light-emitting device according to Example 1 has been binarized after a 700-hour reliability evaluation test, and Fig. 9 shows a photograph in which the light-transmitting surface of the light-emitting device according to Comparative Example 1 has been binarized after a 700-hour reliability evaluation test.

[0120] The first luminance ratio and the second luminance ratio were calculated for each light emitting device after the reliability evaluation test in the same manner as before the reliability evaluation test. The emission spectrum of each light emitting device after the reliability evaluation test was measured in the same manner as before the reliability evaluation test, and the x value and the y value in the chromaticity coordinate of CIE1931 and the correlated color temperature (K) in accordance with JIS Z8725 were measured from the emission spectrum of each light emitting device. Specifically, the x value and the y value in the CIE chromaticity coordinate of the mixed color light emitted from the light emitting device in the initial state before the reliability evaluation test were set as the x1 value and the y1 value, and the light emitting device was repeatedly turned on and off for 30 minutes each at a current of 1200 mA for 700 hours in an environmental tester at 85°C and a relative humidity of 85%, and then the x2 value and the y2 value in the CIE chromaticity coordinate of the mixed color light emitted from the light emitting device were measured, and the absolute values ​​of the difference Δx between the x1 value and the x2 value and the difference Δy between the y1 value and the y2 value were calculated. FIG. 7 shows the emission spectrum of the light emitting device according to Example 1 after the reliability evaluation test described above when the maximum emission intensity is set to 1.

[0121] [Table 3]

[0122] The light emitting devices according to Examples 1 to 6 emitted light with a correlated color temperature of 1800K or more and 5000K or less and a first luminance ratio Ls / L of 0.9 or less even after a 700-hour reliability evaluation test in an environmental tester at 85°C and a relative humidity of 85%. The light emitting devices according to Examples 1 to 6 emitted light with reduced glare.

[0123] The light emitting devices according to Examples 1 to 6 emitted light with a second luminance ratio B / A of 0.104 or less even after a 700-hour reliability evaluation test in an environmental tester at 85°C and 85% relative humidity. The light emitting devices according to Examples 1 to 6 suppress light scattering and emit light that reaches a relatively long distance.

[0124] Furthermore, the light emitting devices of Examples 1 to 6 include a first phosphor having a composition represented by formula (1A), in which the variable e representing the molar ratio of Ce, an activating element, satisfies the range of 0.019 to 0.2 (0.019≦e≦0.2). Therefore, the total amount of phosphor contained in the wavelength conversion member can be made smaller than that of the wavelength conversion member used in the light emitting device of Comparative Example 1, and after a reliability evaluation test of 700 hours in an environmental test chamber at 85°C and a relative humidity of 85%, the rate of peeling that occurred between the wavelength conversion body 41 and the light-transmitting body 42 of the wavelength conversion member 40 was lower than that of the light emitting device of Comparative Example 1, thereby improving durability. Furthermore, the light emitting devices according to Examples 1 to 6 include a first phosphor having a composition represented by formula (1A), and in formula (1A), the variable e representing the molar ratio of Ce, which is an activating element, satisfies the range of 0.019 to 0.2 (0.019≦e≦0.2). Therefore, the values ​​of Δx and Δy representing the change in chromaticity before and after the reliability evaluation test are smaller than the Δx and Δy of the light emitting device according to Comparative Example 1, thereby suppressing chromaticity shift and improving durability.

[0125] There is almost no change in the emission spectrum between the emission spectrum of the light emitting device of Example 1 before the reliability evaluation test shown in FIG. 6 and the emission spectrum of the light emitting device of Example 1 after the reliability evaluation test shown in FIG. 7. After a reliability evaluation test for 700 hours in an environmental test chamber at 85° C. and a relative humidity of 85%, as described above, light with reduced glare is emitted, light scattering is suppressed, and light that reaches a relatively long distance is emitted.

[0126] In the binarized photograph of the light-transmitting surface of the light-emitting device of Example 1 after a 700-hour reliability evaluation test shown in FIG. 8, almost no white peeled off areas were observed, demonstrating the enhanced durability of the light-emitting device.

[0127] In the binarized photograph of the light-transmitting body surface of the light-emitting device according to Comparative Example 1 after a 700-hour reliability evaluation test shown in FIG. 9, many white areas indicating peeled areas between the wavelength converter and the light-transmitting body were observed. [Industrial Applicability]

[0128] The light emitting device according to the embodiment of the present disclosure can be used in a headlamp. A headlamp equipped with the light emitting device according to the embodiment of the present disclosure can be used in vehicles used in road vehicles such as motorcycles and four-wheeled vehicles, railway vehicles, and construction machines such as tractor-type machines for leveling, transporting, and loading, and excavator-type machines for excavation. [Explanation of symbols]

[0129] 1: substrate, 10: light-emitting element, 12: lighting control unit, 22: outer lens, 24: lamp body, 26: optical filter, 28: screw, 32: substrate, 34: light-guiding member, 40: wavelength conversion member, 41: wavelength conversion body, 41a: high-concentration layer, 41b: low-concentration layer, 42: light-transmitting body, 50: semiconductor element, 60: conductive member, 71: first phosphor, 72: second phosphor, 80: adhesive layer, 90: covering member, 100, 101: light-emitting device, 200: headlamp.

Claims

1. A light emitting element having an emission peak wavelength in the range of 400 nm to 490 nm; A wavelength conversion member including a first phosphor having an emission peak wavelength in the range of 480 nm or more and less than 580 nm, and a second phosphor having an emission peak wavelength in the range of 580 nm or more and 680 nm or less and having a composition different from that of the first phosphor; A light emitting device comprising: The light emitting device emits light having a first luminance ratio Ls / L of 0.9 or less, which is a ratio of a first effective radiance Ls of light emitted by the light emitting device in a range of 380 nm to 780 nm inclusive, taking into account the standard luminous efficiency curve for human photopic vision defined by the CIE (International Commission on Illumination), to a luminance L of light emitted by the light emitting device in a range of 380 nm to 780 nm inclusive, taking into account the standard luminous efficiency curve for human photopic vision and the spectral sensitivity of human S-cones, and which is derived from the following formula (1): A light emitting device, wherein the first phosphor comprises a rare earth aluminate phosphor having a composition represented by the following formula (1A): (In formula (1), S(λ) is the spectral radiance of the light emitted by the light emitting device, V(λ) is the standard luminous efficiency curve for human photopic vision defined by the CIE (Commission Internationale de Illumination), and Gs(λ) is the spectral sensitivity of human S-cones in the wavelength λ range of 380 nm to 550 nm.) L １ ３－ｅ Yes ｅ (Al) １－ａ Ga ａ ) ５ O １２ (1A) (In formula (1A), Ln １ is at least one element selected from the group consisting of Y, Gd, Tb and Lu, and a and e satisfy 0≦a≦0.5 and 0.019≦e≦0.

2.

2. The light emitting device according to claim 1 , which emits light having a correlated color temperature of 1800K or more and 5000K or less.

3. The light emitting device according to claim 1 , wherein the first phosphor has an emission spectrum having a full width at half maximum in the range of 90 nm to 125 nm.

4. 3 . The light emitting device according to claim 1 , wherein the second phosphor has an emission spectrum having a full width at half maximum in the range of 3 nm to 15 nm, or an emission spectrum having a full width at half maximum in the range of 60 nm to 120 nm.

5. 3. The light emitting device according to claim 1, wherein the rare earth aluminate phosphor having the composition represented by formula (1A) has an average particle size in the range of 15 μm to 40 μm as measured by a Fischer subsieve sizer method.

6. 3. The light emitting device according to claim 1, wherein the first phosphor includes a rare earth aluminate phosphor having a composition represented by formula (1A) and further includes a first nitride phosphor having a composition represented by formula (1B): La ｗ Ln ２ ｘ Ce z Si 6 N y (1B) (In formula (1B), Ln ２ contains at least one selected from the group consisting of Y and Gd as an essential element, and may contain at least one selected from the group consisting of Sc and Lu, and Ln ２ When the element is 100 mol%, Ln ２ The total amount of Y and Gd contained in is 90 mol % or more, and w, x, y, and z satisfy 1.2≦w≦2.2, 0.5≦x≦1.2, 10≦y≦12, 0.5≦z≦1.2, 1.80<w+x<2.40, and 2.9≦w+x+z≦3.

1.

7. 3. The light emitting device according to claim 1 or 2, wherein the second phosphor comprises at least one selected from the group consisting of a second nitride phosphor having a composition represented by the following formula (2A), a third nitride phosphor having a composition represented by the following formula (2B), a fluoride phosphor having a composition represented by the following formula (2C), a fluoride phosphor having a composition represented by the following formula (2C') which is different in composition from formula (2C), and an α-sialon phosphor having a composition represented by the following formula (2G). M １ ２ Yes ５ N ８ :Eu (2A) (In formula (2A), M １ is an alkaline earth metal element including at least one selected from the group consisting of Ca, Sr, and Ba. Sr ｑ Ca ｓ Al ｔ Yes ｕ N ｖ :Eu (2B) (In formula (2B), q, s, t, u, and v respectively satisfy 0≦q<1, 0<s≦1, q+s≦1, 0.9≦t≦1.1, 0.9≦u≦1.1, and 2.5≦v≦3.5.) A ｃ [M ２ １－ｂ Mn ４＋ ｂ F ｄ ] (2C) (In formula (2C), A is K ＋ , Li ＋ , Na ＋ , Rb ＋ , Cs ＋ and N.H. ４ ＋ At least one selected from the group consisting of M ２ contains at least one element selected from the group consisting of Group 4 elements and Group 14 elements, b satisfies 0<b<0.2, and c satisfies [M ２ １－ｂ Mn ４＋ ｂ F ｄ ] is the absolute value of the charge of the ion, and d satisfies 5<d<7. A’ ｃ’ [M ２ ’ １－ｂ’ Mn ４＋ ｂ’ F ｄ’ ] (2C’) (In formula (2C'), A' is K ＋ , Li ＋ , Na ＋ , Rb ＋ , Cs ＋ and N.H. ４ ＋ At least one selected from the group consisting of M ２ b′ contains at least one element selected from the group consisting of Group 4 elements, Group 13 elements, and Group 14 elements, b′ satisfies 0<b′<0.2, and c′ satisfies [M ２ ' １－ｂ’ Mn ４＋ ｂ’ F ｄ’ ] is the absolute value of the charge of the ion, and d' satisfies 5<d'<7. M ８ ｖ３ Yes １２－（ｗ３＋ｘ３） Al ｗ３＋ｘ３ O ｘ３ N １６－ｘ３ :Eu (2G) (In formula (2G), M ８ contains at least one element selected from the group consisting of Li, Mg, Ca, Sr, Y, and lanthanoid elements (excluding La and Ce), and v3, w3, and x3 satisfy 0<v3≦2.0, 2.0≦w3≦6.0, and 0≦x3≦1.0, respectively.

8. 3. The light emitting device according to claim 1, wherein the wavelength conversion member comprises a wavelength conversion body including the first phosphor and the second phosphor, and a translucent material, and the total amount of the first phosphor and the second phosphor is in the range of 50 parts by mass or more and 500 parts by mass or less per 100 parts by mass of the translucent material in the wavelength conversion body.

9. the wavelength conversion member includes a wavelength conversion body including the first phosphor and the second phosphor, and a light-transmitting material; the wavelength converter includes a high-concentration layer having a high filling rate of the first phosphor and the second phosphor, and a low-concentration layer having a low filling rate of the first phosphor and the second phosphor, The light-emitting device according to claim 1 , wherein the high-concentration layer is disposed on the side of the light-emitting element.

10. A headlamp comprising the light emitting device according to claim 1 or 2.

11. The headlamp according to claim 10 , comprising two or more types of light emitting devices each having a different value of the first luminance ratio Ls / L.

12. 3. A headlamp comprising two or more types of light-emitting devices, the first light-emitting device including the light-emitting device according to claim 1 or 2, and a second light-emitting device emitting light such that a first luminance ratio Ls / L, which is a ratio of a first effective radiance Ls of light emitted by the light-emitting device having a wavelength of 380 nm to 780 nm inclusive taking into account the standard relative luminous efficiency curve for human photopic vision and the spectral sensitivity of human S-cones, and which is derived from the following formula (1), exceeds 0.9: (In formula (1), S(λ) is the spectral radiance of the light emitted by the light emitting device, V(λ) is the standard luminous efficiency curve for human photopic vision defined by the CIE (Commission Internationale de Illumination), and Gs(λ) is the spectral sensitivity of human S-cones in the wavelength λ range of 380 nm to 550 nm.)

13. A light emitting element having an emission peak wavelength in the range of 400 nm to 490 nm; A wavelength conversion member including a first phosphor having an emission peak wavelength in the range of 480 nm or more and less than 580 nm, and a second phosphor having an emission peak wavelength in the range of 580 nm or more and 680 nm or less and having a composition different from that of the first phosphor; A light emitting device comprising: the light emitting device emits light having a second luminance ratio B / A of 0.104 or less, the second luminance ratio B / A being a ratio of a second effective radiance B of light emitted by the light emitting device in the range of 300 nm to 800 nm inclusive, taking into consideration a scattering intensity curve for wavelength when the scattering intensity of Rayleigh scattering at a wavelength of 300 nm is set to 1, to a radiance A of light emitted by the light emitting device in the range of 300 nm to 800 nm inclusive, the second luminance ratio B / A being derived from the following formula (2): A light emitting device, wherein the first phosphor comprises a rare earth aluminate phosphor having a composition represented by the following formula (1A): (In formula (2), S(λ) is the spectral radiance of the light emitted by the light emitting device, and Dc(λ) is a scattering intensity curve for Rayleigh scattering with the scattering intensity of Rayleigh scattering at a wavelength of 300 nm set to 1.) L １ ３－ｅ Yes ｅ (Al) １－ａ Ga ａ ) ５ O １２ (1A) (In formula (1A), Ln １ is at least one element selected from the group consisting of Y, Gd, Tb and Lu, and a and e satisfy 0≦a≦0.5 and 0.019≦e≦0.

2.

14. The light emitting device according to claim 13, which emits light having a correlated color temperature of 1800K or more and 5000K or less.

15. The light emitting device according to claim 13 , wherein the first phosphor has an emission spectrum having a full width at half maximum in the range of 90 nm to 125 nm.

16. 15. The light emitting device according to claim 13, wherein the second phosphor has an emission spectrum having a full width at half maximum in the range of 3 nm to 15 nm, or an emission spectrum having a full width at half maximum in the range of 60 nm to 120 nm.

17. The light emitting device according to claim 13 or 14, wherein the first phosphor includes a rare earth aluminate phosphor having a composition represented by the formula (1A), and further includes a first nitride phosphor having a composition represented by the following formula (1B): La ｗ Ln ２ ｘ Ce z Si 6 N y (1B) (In formula (1B), Ln ２ contains at least one selected from the group consisting of Y and Gd as an essential element, and may contain at least one selected from the group consisting of Sc and Lu, and Ln ２ When the element is 100 mol%, Ln ２ The total amount of Y and Gd contained in is 90 mol % or more, and w, x, y, and z satisfy 1.2≦w≦2.2, 0.5≦x≦1.2, 10≦y≦12, 0.5≦z≦1.2, 1.80<w+x<2.40, and 2.9≦w+x+z≦3.

1.

18. The light emitting device according to claim 13 or 14, wherein the second phosphor comprises at least one selected from the group consisting of a second nitride phosphor having a composition represented by the following formula (2A), a third nitride phosphor having a composition represented by the following formula (2B), and a fluoride phosphor having a composition represented by the following formula (2C), a fluoride phosphor having a composition represented by the following formula (2C') which is different in composition from formula (2C), and an α-sialon phosphor having a composition represented by the following formula (2G). M １ ２ Yes ５ N ８ :Eu (2A) (In formula (2A), M １ is an alkaline earth metal element including at least one selected from the group consisting of Ca, Sr, and Ba. Sr ｑ Ca ｓ Al ｔ Yes ｕ N ｖ :Eu (2B) (In formula (2B), q, s, t, u, and v respectively satisfy 0≦q<1, 0<s≦1, q+s≦1, 0.9≦t≦1.1, 0.9≦u≦1.1, and 2.5≦v≦3.5.) A ｃ [M ２ １－ｂ Mn ４＋ ｂ F ｄ ] (2C) (In formula (2C), A is K ＋ , Li ＋ , Na ＋ , Rb ＋ , Cs ＋ and N.H. ４ ＋ At least one selected from the group consisting of M ２ contains at least one element selected from the group consisting of Group 4 elements and Group 14 elements, b satisfies 0<b<0.2, and c satisfies [M ２ １－ｂ Mn ４＋ ｂ F ｄ ] is the absolute value of the charge of the ion, and d satisfies 5<d<7. A’ ｃ’ [M ２ ’ １－ｂ’ Mn ４＋ ｂ’ F ｄ’ ] (2C’) (In formula (2C'), A' is K ＋ , Li ＋ , Na ＋ , Rb ＋ , Cs ＋ and N.H. ４ ＋ At least one selected from the group consisting of M ２ b′ contains at least one element selected from the group consisting of Group 4 elements, Group 13 elements, and Group 14 elements, b′ satisfies 0<b′<0.2, and c′ satisfies [M ２ ' １－ｂ’ Mn ４＋ ｂ’ F ｄ’ ] is the absolute value of the charge of the ion, and d' satisfies 5<d'<7. M ８ ｖ３ Yes １２－（ｗ３＋ｘ３） Al ｗ３＋ｘ３ O ｘ３ N １６－ｘ３ :Eu (2G) (In formula (2G), M ８ contains at least one element selected from the group consisting of Li, Mg, Ca, Sr, Y, and lanthanoid elements (excluding La and Ce), and v3, w3, and x3 satisfy 0<v3≦2.0, 2.0≦w3≦6.0, and 0≦x3≦1.0, respectively.

19. 15. The light emitting device according to claim 13, wherein the rare earth aluminate phosphor having the composition represented by formula (1A) has an average particle size, measured by a Fischer subsieve sizer method, in the range of 15 μm to 40 μm.

20. 15. The light emitting device according to claim 13, wherein the wavelength conversion member comprises a wavelength conversion body including the first phosphor and the second phosphor, and a translucent material, and the total amount of the first phosphor and the second phosphor is in the range of 50 parts by mass or more and 500 parts by mass or less per 100 parts by mass of the translucent material in the wavelength conversion body.

21. the wavelength conversion member includes a wavelength conversion body including the first phosphor and the second phosphor, and a light-transmitting material; the wavelength converter includes a high-concentration layer having a high filling rate of the first phosphor and the second phosphor, and a low-concentration layer having a low filling rate of the first phosphor and the second phosphor, The light-emitting device according to claim 13 or 14, wherein the high concentration layer is disposed on the side of the light-emitting element.

22. A headlamp comprising the light emitting device according to claim 13 or 14.

23. The headlamp according to claim 22 , comprising two or more types of light emitting devices each having a different value of the second luminance ratio B / A.

24. A first light emitting device comprising the light emitting device according to claim 13 or 14; A headlamp comprising two or more types of second light-emitting devices that emit light such that a second luminance ratio B / A, which is a ratio of a second effective radiance B of light emitted by the light-emitting device in the range of 300 nm to 800 nm inclusive, taking into account a scattering intensity curve for wavelength when the scattering intensity of Rayleigh scattering at a wavelength of 300 nm is set to 1, to a radiance A of light emitted by the light-emitting device in the range of 300 nm to 800 nm inclusive, and is derived from the following formula (2): (In formula (2), S(λ) is the spectral radiance of the light emitted by the light emitting device, and Dc(λ) is a scattering intensity curve for Rayleigh scattering with the scattering intensity of Rayleigh scattering at a wavelength of 300 nm set to 1.)

25. A vehicle comprising the light emitting device according to claim 1 or 13.

26. A vehicle comprising the headlamp according to claim 12 or 24.

Images