Light-emitting device, luminaire, and street lamp

Abstract

To provide a light-emitting device, a lamp, and a street light capable of reducing glare.SOLUTION: A 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 first phosphor having an emission peak wavelength in the range of 570 nm or more and 680 nm or less, the light-emitting device has a correlated color temperature of 1950K or less, a general color rendering index Ra of 51 or more, and a full width at half maximum of the emission peak with the maximum emission intensity in the emission spectrum of the light emitting device of 110 nm or less, and when the luminance of the light emission of the light-emitting device in the range of 380 nm or more and 780 nm or less in consideration of the human photopic standard ratio luminosity defined by CIE is L, and the first effective radiance of light emitted from the light-emitting device with a wavelength of 380 nm or more and 780 nm or less in consideration of the human photopic standard ratio luminosity and the sensitivity of the human S cone is Ls1, light is emitted in which a first glare index Ls1 / L of the first effective radiance Ls1 with respect to the luminance L is 0.493 or less.SELECTED DRAWING: Figure 4

Description

Technical Field

[0001] The present invention relates to a light-emitting device, a lighting fixture, and a street lamp.

Background Art

[0002] Light sources of lighting fixtures installed outdoors such as street lamps and road lighting lamps have a longer lifespan and higher efficiency than incandescent bulbs. Therefore, HID lamps such as high-pressure mercury lamps, metal halide lamps, and high-pressure sodium lamps are widely used. The light sources using these lamps use mercury in the light-emitting material, and with the regulations of the Minamata Convention on mercury, there is a demand for alternatives to lighting fixtures using safe light-emitting materials.

[0003] For example, Patent Document 1 discloses a street lamp lighting fixture in which a lighting LED is arranged at the center, a viewing LED having a lower brightness than the lighting LED or a wide viewing angle is arranged outside the lighting LED, a partition wall for partitioning between the lighting LED and the viewing LED is arranged, and a lighting opening for emitting lighting light is formed at the open end of the partition wall.

Prior Art Documents

Patent Documents

[0004]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0005] Light emitted from a luminaire used outdoors may stimulate the vision of a driver or a pedestrian of a moving vehicle, causing glare that gives a feeling of discomfort or difficulty in seeing things. Glare is a sensation caused by an inappropriate luminance distribution and an extreme luminance contrast within the visual field, and is accompanied by discomfort and a decrease in the ability to see (JIS Z9110). Luminaires used outdoors are required to not overly stimulate the vision of a driver or a pedestrian of a moving vehicle and to make it easier to see things. Luminaires used outdoors include, in addition to streetlights and road lighting fixtures installed outdoors, for example, headlights that can be worn on a person's head, flashlights, or portable lanterns using LEDs, for which outdoor use is assumed. Also, even for luminaires used indoors but assumed to be used in locations near the outdoors such as near entrances or windows, it is desired to reduce glare. An aspect of the present invention aims to provide a light-emitting device, a luminaire, and a streetlight capable of reducing glare.

Means for Solving the Problem

[0006] A first aspect is a light-emitting device including a light-emitting element having an emission peak wavelength within a range of 400 nm or more and 490 nm or less, and a first phosphor having an emission peak wavelength within a range of 570 nm or more and 680 nm or less, wherein the light-emitting device has a correlated color temperature of 1950 K or less, an average color rendering evaluation index Ra of 51 or more, a full width at half maximum of an emission peak having the maximum emission intensity in the emission spectrum of the light-emitting device of 110 nm or less, the luminance of the light emission of the light-emitting device in a range of 380 nm or more and 780 nm or less considering the photopic standard spectral luminous efficiency of a human defined by the CIE (International Commission on Illumination) is L, and the first effective radiated luminance Ls1 of the light emission of the light-emitting device in a range of 380 nm or more and 780 nm or less considering the photopic standard spectral luminous efficiency of the human and the sensitivity of the human S cones, and emits light for which a first glare index Ls1 / L of the first effective radiated luminance Ls1 with respect to the luminance L defined by the following formula (1) is 0.493 or less.

[0007]

Number

[0008] A second aspect is a light-emitting device including a light-emitting element having an emission peak wavelength in the range of 400 nm or more and 490 nm or less, and a first phosphor having an emission peak wavelength in the range of 570 nm or more and 680 nm or less, wherein the first phosphor includes a first nitride phosphor having a composition represented by the following formula (1A), the light-emitting device has a correlated color temperature of 1950 K or less, a full width at half maximum of an emission peak having the maximum emission intensity in the emission spectrum of the light-emitting device is 110 nm or less, the luminance of the light emission of the light-emitting device in the range of 380 nm or more and 780 nm or less considering the photopic standard luminosity curve of the human eye defined by the CIE (International Commission on Illumination) is L, and when the first effective radiant luminance Ls1 of the light emission of the light-emitting device in the range of 380 nm or more and 780 nm or less considering the photopic standard luminosity curve of the human eye and the sensitivity of the S-cone of the human eye is defined by the following formula (1), a light-emitting device that emits light with a first glare index Ls1 / L of the first effective radiant luminance Ls1 with respect to the luminance L of 0.493 or less.) M 1 2Si5N8:Eu (1A) (In formula (1A), M 1 is an alkaline earth metal element containing at least one selected from the group consisting of Ca, Sr, and Ba.)

[0009] A third aspect is a light-emitting device including a light-emitting element having an emission peak wavelength in the range of 400 nm or more and 490 nm or less, and a first phosphor having an emission peak wavelength in the range of 570 nm or more and 680 nm or less, wherein the light-emitting device has a correlated color temperature of 1950 K or less, an average color rendering index Ra of 51 or more, a full width at half maximum of an emission peak having the maximum emission intensity in the emission spectrum of the light-emitting device of 110 nm or less, and when the luminance of the light emission of the light-emitting device in the range of 380 nm or more and 780 nm or less considering the photopic standard luminosity curve of a human defined by the CIE (International Commission on Illumination) is L, and the second effective radiant luminance Ls2 of the light emission of the light-emitting device in the range of 380 nm or more and 780 nm or less considering the photopic standard luminosity curve of a human and the sensitivity of the S cone of a human when shifted by -10 degrees to +10 degrees with respect to the central visual field angle defined by the CIE, the light-emitting device emits light such that the second glare index Ls2 / L of the second effective radiant luminance Ls2 with respect to the luminance L defined by the following formula (2) is 1.082 or less.

[0010] [Number] (In formula (2), S(λ) is the spectral radiant luminance of the light emission of the light-emitting device, V(λ) is the photopic standard luminosity curve of a human defined by the CIE (International Commission on Illumination), Gs(λ) is the spectral sensitivity of the S cone of a human in the range where the wavelength λ nm is 380 nm or more and 550 nm or less, and V 10 (λ) is the photopic standard luminosity curve of a human when shifted by -10 degrees to +10 degrees with respect to the central visual field angle defined by the CIE.)

[0011] The fourth aspect is a light-emitting device including a light-emitting element having an emission peak wavelength within a range of 400 nm or more and 490 nm or less, and a first phosphor having an emission peak wavelength within a range of 570 nm or more and 680 nm or less, wherein the first phosphor includes a first nitride phosphor having a composition represented by the formula (1A), the light-emitting device has a correlated color temperature of 1950 K or less, a full width at half maximum of an emission peak having the maximum emission intensity in the emission spectrum of the light-emitting device is 110 nm or less, the luminance of the light emission of the light-emitting device in the range of 380 nm or more and 780 nm or less considering the human photopic standard specific sensitivity defined by the CIE (International Commission on Illumination) is L, and the second effective emission luminance Ls2 of the light emission of the light-emitting device in the range of 380 nm or more and 780 nm or less considering the human photopic standard specific sensitivity when shifted by -10 degrees to +10 degrees with respect to the central visual field angle and the sensitivity of the human S cone defined by the CIE, the light-emitting device emits light such that a second glare index Ls2 / L of the second effective emission luminance Ls2 with respect to the luminance L defined by the formula (2) is 1.082 or less.

[0012] The fifth aspect is a luminaire including the light-emitting device.

[0013] The sixth aspect is a street lamp including the light-emitting device.

Advantages of the Invention

[0014] According to one aspect of the present invention, it is possible to provide a light-emitting device, a luminaire, and a street lamp capable of reducing glare.

Brief Description of the Drawings

[0015]

Figure 1A

Figure 1B

Figure 1C

Figure 2

Figure 3A

Figure 3B

Figure 4

Figure 5

Figure 6

Figure 7

Figure 8

Figure 9

Figure 10

Figure 11

Figure 12

Figure 13

Figure 14

Figure 15

Figure 16

Mode for Carrying Out the Invention

[0016] Hereinafter, embodiments of the present invention will be described with reference to the drawings. However, the embodiments shown below are examples for embodying the technical idea of the present invention, and the present invention is not limited to the following light-emitting devices, lighting fixtures, and streetlights. Also, the members shown in the claims are by no means limited to the members of the embodiments. In particular, the dimensions, materials, shapes, relative arrangements, etc. of the components described in the embodiments are not intended to limit the scope of the present invention only to those, but are merely illustrative examples. Note that the relationship between color names and chromaticity coordinates, the relationship between the wavelength range of light and the color names of monochromatic light, etc. follow JIS Z8110. In this specification, the content of each component in the composition means the total amount of the plurality of substances present in the composition when there are a plurality of substances corresponding to each component in the composition, unless otherwise specified. The full width at half maximum means the wavelength width of the emission peak showing the emission intensity of 50% of the maximum emission intensity in the emission spectrum.

[0017] The light-emitting device according to the first embodiment is a light-emitting device including a light-emitting element having an emission peak wavelength in the range of 400 nm or more and 490 nm or less, and a first phosphor having an emission peak wavelength in the range of 570 nm or more and 680 nm or less. The light-emitting device has a correlated color temperature (CCT) of 1950 K or less, an average color rendering evaluation index Ra of 51 or more, a full width at half maximum of an emission peak having the maximum emission intensity in the emission spectrum of the light-emitting device of 110 nm or less. Taking the luminance of the light emission of the light-emitting device in the range of 380 nm or more and 780 nm or less into consideration of the photopic standard relative luminous efficiency defined by the CIE (International Commission on Illumination) as L, and taking the first effective radiant luminance Ls1 of the light emission of the light-emitting device in the range of 380 nm or more and 780 nm or less into consideration of the photopic standard relative luminous efficiency of the human and the sensitivity of the S cones of the human, the first glare index Ls1 / L of the first effective radiant luminance Ls1 with respect to the luminance L defined by the following formula (1) is 0.493 or less, and emits light.

[0018] [Number] (In formula (1), S(λ) is the spectral radiant luminance of the light emission of the light-emitting device, V(λ) is the photopic standard relative luminous efficiency curve defined by the CIE (International Commission on Illumination), and Gs(λ) is the spectral sensitivity of the S cones of the human in the range where the wavelength λ nm is 380 nm or more and 550 nm or less.)

[0019] For example, high-pressure sodium lamps, which are used as light sources for outdoor fixtures such as street lamps and road lighting fixtures, have a correlated color temperature of about 2,000 K to 2,500 K in catalog values and emit light with a large amount of yellow to orange components. As light sources for outdoor fixtures, light sources such as HID lamps, halogen lamps, and light-emitting devices using LEDs are used depending on characteristics such as luminous flux and energy. Due to differences in light sources, glare that causes a dazzling and uncomfortable feeling and apparent brightness are different. Non-Patent Document 1 discloses that LED light sources with a high color temperature of, for example, 6,600 K are evaluated as dazzling by humans regardless of whether they are elderly or non-elderly (Non-Patent Document 1: Hiroshi Hashimoto et al., "Influence of Color Temperature Difference of White LEDs on Dazzle," Japan Automobile Research Institute, Inc., Preventive Safety Research Department, October 2006, Automobile Research, Vol. 28, No. 10, pp. 569 to 572). Glare that makes humans feel uncomfortable also differs depending on a decrease in human retinal illuminance and deterioration of rod cells, and the degree of dazzle may change depending on a human's age. Among cone cells, which are photoreceptor cells present in the human retina, S cones respond to short-wavelength light. S cones have a peak wavelength of sensitivity at around 440 nm. Non-Patent Document 2 discloses the following formula (3) for a new spectral luminous efficiency V K (λ) corresponding to glare, which takes into account the spectral sensitivity Gs(λ) of human S cones at wavelength λ in the photopic standard luminosity curve V(λ) of humans used in the side-light system of the CIE1931 color system (Non-Patent Document 2: Shoji Kobayashi et al., "Research on the Influence of Spectral Distribution of Headlamp Light Sources on Uncomfortable Glare," Society of Automotive Engineers of Japan, Inc., Preprint of Academic Lecture, Nos. 5 to 10, pp. 9 to 14).

[0020]

Equation

[0021] Figure 1A shows the spectral sensitivity Gs(λ) of the human S cones disclosed in Non-Patent Document 2. Based on Figure 1A, the numerical values of the spectral sensitivity Gs(λ) of the human S cones can be derived. The spectral sensitivity Gs(λ) of the human S cones has a peak of spectral sensitivity within the range of 380 nm or more and 550 nm or less. Figure 1B shows the human photopic standard relative luminous efficiency curve V(λ) defined by the CIE and disclosed in Non-Patent Document 2. The relative values shown in Figures 1A to 1C are values with the peak top of the human photopic standard relative luminous efficiency curve V(λ) defined by the CIE set to 1. Based on Figure 1B, the numerical values of the human photopic standard relative luminous efficiency curve V(λ) defined by the CIE can be derived. Figure 1C is a curve corresponding to V K (λ):K = 1.260, and is an example of the spectral luminous efficiency V K (λ) that takes into account the human photopic standard relative luminous efficiency curve defined by the CIE and the spectral sensitivity of the human S cones corresponding to glare. K is a coefficient that determines the proportion contributed by the spectral sensitivity Gs(λ) of the human S cones.

[0022] The luminance L of the light emission of the light-emitting device is derived by the following formula (4). The luminance L of the light emission of the light-emitting device is the integrated value of the spectral radiance S(λ) of the light-emitting device in the range of 380 nm or more and 780 nm or less and the human photopic standard relative luminous efficiency curve V(λ) defined by the CIE.

[0023]

Equation

[0024] The first effective radiance Ls1 of the light emission of the light-emitting device is derived by the following formula (5). The first effective radiance Ls1 of the light emission of the light-emitting device is the integrated value of the spectral radiance S(λ) of the light-emitting device in the range of 380 nm or more and 780 nm or less and the human spectral luminous efficiency V K (λ)(= 1.260 × Gs(λ) + V(λ)) corresponding to glare represented by the above formula (3), divided by 2.3 which is the peak top of V K (λ) derived by the above formula (3) using the coefficient K(= 1.260) in the case of an incandescent lamp.

[0025]

Number

[0026] The first glare index Ls1 / L of the light emission of the light-emitting device is the ratio of the first effective emission luminance Ls1 of the light emission of the light-emitting device considering the CIE-defined photopic standard relative sensitivity curve of the human eye and the spectral sensitivity of the human S cone to the luminance L of the light emission of the light-emitting device considering the CIE-defined photopic standard relative sensitivity curve of the human eye. The first glare index Ls1 / L represents the degree of glare of the light emission of the light-emitting device.

[0027] The light-emitting device of the first embodiment is a light-emitting device including a light-emitting element having a light emission peak wavelength in the range of 400 nm or more and 490 nm or less, and a first phosphor having a light emission peak wavelength in the range of 570 nm or more and 680 nm or less, and the light-emitting device emits light in which the first glare index Ls1 / L derived from the formula (1) is 0.493 or less.

[0028] If the first glare index Ls1 / L of the light emission of the light-emitting device is 0.493 or less, light that reduces glare that makes a human feel dazzling and uncomfortable can be emitted from the light-emitting device provided in, for example, a luminaire used outdoors. If the first glare index Ls1 / L of the light emission of the light-emitting device is 0.493 or less, even when the luminaire is not equipped with two types of LEDs, namely, a lighting LED and a viewing LED with a lower luminance or a wide viewing angle than the lighting LED, light with reduced glare can be emitted. When the first glare index Ls1 / L of the light emission of the light-emitting device exceeds 0.493, light approaching the luminance L of the light emission of the light-emitting device that does not consider the spectral sensitivity of the S cones of the human eye is emitted. For example, as the light emitted from a luminaire used outdoors, a human feels dazzling and the glare is not reduced. For example, as a light-emitting device provided in a luminaire used outdoors or a luminaire used indoors in a place near outdoors such as near a window, in order to reduce the glare that makes a human feel dazzling and uncomfortable, the first glare index Ls1 / L of the light emission of the light-emitting device is preferably 0.492 or less, may be 0.490 or less, or may be 0.485 or less. Considering the spectral sensitivity of the S cones of the human eye, the first glare index Ls1 / L of the light emission of the light-emitting device may be 0.100 or more, or may be 0.200 or more.

[0029] The light-emitting device that emits light with the first glare index Ls1 / L of 0.493 or less preferably emits light with the second glare index Ls2 / L of 1.082 or less, which will be described later. The light-emitting device that emits light with the first glare index Ls1 / L of 0.492 or less and the second glare index Ls2 / L of 1.082 or less, which will be described later, can reduce the glare that makes a human feel dazzling and uncomfortable, whether looking at a relatively narrow range of areas or a relatively wide range of areas.

[0030] The light-emitting device according to the third embodiment is a light-emitting device including a light-emitting element having an emission peak wavelength in the range of 400 nm or more and 490 nm or less, and a first phosphor having an emission peak wavelength in the range of 570 nm or more and 680 nm or less. The light-emitting device has a correlated color temperature of 1950 K or less, an average color rendering evaluation index Ra of 51 or more, a full width at half maximum of an emission peak having the maximum emission intensity in the emission spectrum of the light-emitting device of 110 nm or less. Taking the luminance of the light emission of the light-emitting device in the range of 380 nm or more and 780 nm or less into account the photopic standard specific sensitivity of humans defined by the CIE (International Commission on Illumination) as L, and the second effective radiant luminance Ls2 of the light emission of the light-emitting device in the range of 380 nm or more and 780 nm or less taking into account the photopic standard specific sensitivity of humans and the sensitivity of the S cones of humans when shifted by -10 degrees to +10 degrees with respect to the central visual field angle defined by the CIE, when the second glare index Ls2 / L of the second effective radiant luminance Ls2 with respect to the luminance L defined by the following formula (2) is 1.082 or less, it emits light.

[0031]

Equation

[0032] The glare that humans feel dazzling and uncomfortable also varies depending on the size of the area that humans see. In the CIE1931 color system, a relatively narrow field of view with an angle subtended at the human eye (viewing angle) of about 1 degree to about 4 degrees is also called the 2-degree field of view equal-energy function, and a relatively wide field of view exceeding a viewing angle of 4 degrees is also called the 10-degree field of view equal-energy function. In Non-Patent Document 3, the photopic standard visual sensitivity curve V at a viewing angle of 10 degrees used in the side-light system of the CIE1931 color system 10(λ) (the photopic standard sensitivity curve when shifted by -10 degrees to +10 degrees with respect to the central visual field angle defined by the CIE), the spectral sensitivity Gs(λ) of the human S cones at wavelength λ, and the spectral visual sensitivity V corresponding to glare, considering the viewing angle coefficient k with respect to the central visual field angle DG (λ) is disclosed in the following formula (6) (Non-Patent Document 3: J.D. Bullough, “Spectral sensitivity for extrafoveal discomfort glare”, Journal of Modern Optics, vol. 56, No. 13, 20 July 2009, 1518 - 1522). Non-Patent Document 3 discloses that the constant k at a viewing angle of 10 degrees is 0.75. FIG. 2 shows the spectral visual sensitivity V corresponding to glare considering a viewing angle of 10 degrees with respect to the central visual field angle disclosed in Non-Patent Document 3 DG (λ) is an illustration.

[0033]

Equation

[0034] The second effective radiance Ls2 of the light-emitting device considering the human viewing angle when viewing a relatively wide area is derived by the following formula (7). The second effective radiance Ls2 is the spectral radiance S(λ) of the light-emitting device in the range of 380 nm or more and 780 nm or less, and the human spectral visual sensitivity V corresponding to glare considering a viewing angle of 10 degrees for viewing a relatively wide area represented by the above formula (6) DG (λ) (= 0.75 × Gs(λ) + V 10 (λ)) and is the integral value.

[0035]

Equation

[0036] The second glare index Ls2 / L of the light-emitting device is the CIE-defined human photopic standard specific sensitivity curve V considering a human viewing angle of 10 degrees for viewing a relatively wide area with respect to the luminance L of the light emission of the light-emitting device considering the CIE-defined human photopic standard specific sensitivity curve10 It is the ratio of the second effective radiance Ls2 of the light emission of a light-emitting device considering the spectral sensitivity of the human S cones when viewing (λ) and a relatively wide area (viewing angle 10 degrees). The second glare index Ls2 / L indicates the degree of glare of the light emission of the light-emitting device when viewing a relatively wide area.

[0037] If the second glare index Ls2 / L of the light emission of the light-emitting device is 1.082 or less, even when viewing a relatively wide range of areas, light that reduces the glare that humans feel dazzling and uncomfortable is emitted from the light-emitting device. If the second glare index Ls2 / L of the light emission of the light-emitting device is 1.082 or less, there are no two types of LEDs, namely, an illumination LED and a viewing LED with a lower luminance or a wide directivity angle than the illumination LED, provided in the luminaire, and even when viewing a relatively wide area, light with reduced glare can be emitted. When the second glare index Ls2 / L of the light emission of the light-emitting device exceeds 1.082, as the light emitted from a luminaire used outdoors, for example, or a luminaire used indoors in a location close to the outdoors such as near a window, humans feel dazzling and the glare is not reduced. For example, for a light-emitting device provided in a luminaire used outdoors or indoors in a location close to the outdoors and thus requiring viewing of a relatively wide area, in order to reduce the glare that humans feel dazzling and uncomfortable, the second glare index Ls2 / L of the light emission of the light-emitting device is preferably 1.081 or less, more preferably 1.080 or less, and may also be 1.079 or less. Considering the spectral sensitivity of the human S cones, the second glare index Ls2 / L of the light emission of the light-emitting device may be 0.200 or more or 0.500 or more.

[0038] The light-emitting device emits light with a correlated color temperature of 1950 K or less. The light-emitting device emits light with a correlated color temperature that is about the same as or slightly lower than the light emitted by, for example, a high-pressure sodium lamp. When the correlated color temperature of the light emitted by the light-emitting device is 1950 K or less, even when the light-emitting device is used as a light source for outdoor luminaires such as streetlights and road lights that use a high-pressure sodium lamp as a light source, light that does not cause a sense of discomfort is emitted. The correlated color temperature of the light emitted from the light-emitting device may be 1920 K or less, or may be 1900 K or less. In order for the light emitted from the light-emitting device not to cause a sense of discomfort to humans as the light emitted from, for example, an outdoor luminaire, the correlated color temperature is preferably 1000 K or more, may be 1200 K or more, may be 1500 K or more, or may be 1700 K or more.

[0039] The average color rendering evaluation number Ra of the light emission of the light-emitting device may be 5 or more, may be 10 or more, may be 20 or more, may be 30 or more, may be 40 or more, is preferably 51 or more, and more preferably 62 or more. The average color rendering evaluation number of the light emission of the light-emitting device can be measured in accordance with JIS Z8726. The closer the value of the average color rendering evaluation number Ra of the light emission of the light-emitting device is to 100, the closer the color rendering property is to that of a reference light source. Color rendering property represents the degree of how an irradiated object looks. Outdoor luminaires such as streetlights and road lights only need to emit light with an average color rendering evaluation number Ra of 5 or more, and may emit light with an average color rendering evaluation number Ra of more than 30 and less than 40.

[0040] The special color rendering evaluation number R9 of the light emission of the light-emitting device is an index for evaluating red. Light-emitting devices used in luminaires installed in outdoor or indoor locations that are close to the outdoors, such as streetlights and road lights, often have little need to confirm red. The special color rendering evaluation number R9 of the light emission of the light-emitting device may be a negative value. The special color rendering evaluation number R9 of the light emission of the light-emitting device may be within the range of -150 or more and +99 or less, may be within the range of -140 or more and +98 or less, or may be within the range of -135 or more and 95 or less.

[0041] The light-emitting device has a full width at half maximum of a light-emitting peak having the maximum light-emitting intensity in the emission spectrum of the light-emitting device of 110 nm or less, which may be 100 nm or less, 95 nm or less, 90 nm or less, 3 nm or more, 40 nm or more, 60 nm or more, or 70 nm or more. In the emission spectrum of the light-emitting device, if the full width at half maximum of the light-emitting peak having the maximum light-emitting intensity is large, the component of light on the long-wavelength side that is difficult for humans to perceive tends to increase, or the component of light on the short-wavelength side that is likely to cause dazzling glare tends to increase. When the component of light on the long-wavelength side increases, the luminance of the light emitted from the light-emitting device tends to decrease. When the component of light on the short-wavelength side increases, it tends to cause discomfort and reduce the ability to see. Also, in the emission spectrum of the light-emitting device, if the full width at half maximum of the light-emitting peak having the maximum light-emitting intensity is small, the component of light in a specific wavelength range tends to increase. In the emission spectrum of the light-emitting device, when the light-emitting peak having the maximum light-emitting intensity is on the short-wavelength side, the short-wavelength emission that is likely to cause dazzling glare is not suppressed, making it difficult to reduce glare. Further, in the emission spectrum of the light-emitting device, when the light-emitting peak having the maximum light-emitting intensity is on the long-wavelength side and the component of light on the long-wavelength side that is difficult for humans to perceive increases, it becomes difficult to suppress the decrease in luminance. In order to provide a light-emitting device that emits light with reduced glare, it is preferable that the full width at half maximum of the light-emitting peak having the maximum light-emitting intensity in the emission spectrum is 110 nm or less.

[0042] The full width at half maximum of the emission peak having the maximum emission intensity in the emission spectrum of the light-emitting device may be narrower than the full width at half maximum of the emission peak having the emission peak wavelength of the first phosphor provided in the light-emitting device or the full width at half maximum of the emission peak having the emission peak wavelength of the second phosphor. For example, when the first phosphor and the second phosphor having emission peak wavelengths in different wavelength ranges are provided, the emission intensity of the overlapping portion of the emission spectrum of the first phosphor and the emission spectrum of the second phosphor changes, and as a result, the emission spectrum of the mixed-color light emitted from the light-emitting device is different from the emission spectrum of the first phosphor or the emission spectrum of the second phosphor, and may be narrower than the full width at half maximum of the emission peak having the emission peak wavelength of the first phosphor or the full width at half maximum of the emission peak having the emission peak wavelength of the second phosphor.

[0043] It is preferable that the emission peak wavelength having the maximum emission intensity in the emission spectrum of the light-emitting device is in the range of 570 nm or more and 680 nm or less, may be in the range of 575 nm or more and 680 nm or less, and may be in the range of 575 nm or more and 670 nm or less. The range of the emission peak wavelength having the maximum emission intensity in the emission spectrum of the light-emitting device may overlap with the range of the emission peak wavelength of the first phosphor. The emission peak having the maximum emission intensity in the emission spectrum of the light-emitting device may be due to the emission of the first phosphor.

[0044] Light-emitting element The light-emitting element has an emission peak wavelength within the range of 400 nm or more and 490 nm or less. The emission peak wavelength of the light-emitting element is preferably within the range of 420 nm or more and 480 nm or less, and may further be within the range of 440 nm or more and 460 nm or less. Thereby, the light-emitting device has a correlated color temperature that does not give a sense of incongruity when illuminating the outdoors, satisfies the color rendering property required for the light for illuminating the outdoors, and emits light with reduced glare. At least a part of the light emission of the light-emitting element is used as excitation light for the first phosphor, and when the second phosphor is included, it is used as excitation light for the second phosphor. Also, a part of the light emission of the light-emitting element is used as the light emitted from the light-emitting device. The full width at half maximum of the emission peak having the emission peak wavelength in the emission spectrum of the light-emitting element is preferably 30 nm or less, more preferably 25 nm or less, and still more preferably 20 nm or less. As the light-emitting element, for example, a semiconductor light-emitting element using a nitride-based semiconductor is preferably used. Thereby, a light-emitting device with high efficiency, high linearity of output with respect to input, and strong resistance to mechanical shock can be obtained.

[0045] First phosphor The light-emitting device includes a first phosphor having an emission peak wavelength in the range of 570 nm or more and 680 nm or less. The first phosphor is excited by the emission of a light-emitting element having an emission peak wavelength in the range of 400 nm or more and 490 nm or less, and emits light having an emission peak wavelength in the range of 570 nm or more and 680 nm or less. The first phosphor may have an emission peak wavelength in the range of 575 nm or more and 670 nm or less, or may have an emission peak wavelength in the range of 580 nm or more and 660 nm or less. It is preferable that the full width at half maximum of the emission peak having the emission peak wavelength in the emission spectrum of the first phosphor is in the range of 3 nm or more and 120 nm or less. The full width at half maximum having the emission peak wavelength in the emission spectrum of the first phosphor is preferably in the range of 3 nm or more and 15 nm or less, or in the range of 60 nm or more and 120 nm or less. For example, in order to have a correlated color temperature that does not cause a sense of incongruity as a luminaire used outdoors, satisfy the color rendering properties required for a luminaire used outdoors, and emit light with reduced glare, the full width at half maximum of the emission peak having the emission peak wavelength in the emission spectrum of the first phosphor is preferably within the above range.

[0046] The first phosphor preferably contains at least one selected from the group consisting of a first nitride phosphor having a composition represented by the following formula (1A), a second nitride phosphor having a composition represented by the following formula (1B), a fluoride phosphor having a composition represented by the following formula (1C), and a fluoride phosphor having a composition represented by the following formula (1C') which has a different composition from the following formula (1C). By including the first phosphor, the light-emitting device has a correlated color temperature of 1950 K or less, for example, an average color rendering evaluation number Ra of 51 or more as the color rendering properties required for a luminaire used outdoors, the full width at half maximum of the emission peak having the maximum emission intensity in the emission spectrum of the light-emitting device is 110 nm or less, and can emit light with reduced glare having a first glare index Ls1 / L of 0.493 or less. Further, by including the first phosphor, the light-emitting device can emit light with reduced glare having a second glare index Ls2 / L of 1.082 or less. M 1 2Si5N8:Eu (1A) (In formula (1A), M1 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 (1B) (In formula (1B), q, s, t, u, v satisfy 0 ≦ q < 1, 0 < s ≦ 1, q + s ≦ 1, 0.9 ≦ t ≦ 1.1, 0.9 ≦ u ≦ 1.1, 2.5 ≦ v ≦ 3.5 respectively.) A c [M 2 1-b Mn 4+ b F d (1C) (In formula (1C), A is at least one selected from the group consisting of K + , Li + , Na + , Rb + , Cs + and NH4 + and preferably includes at least one selected from the group consisting of 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’ (1C’) (In formula (1C’), A’ is at least one selected from the group consisting of K + , Li + , Na + , Rb + , Cs + and NH4 + and preferably includes at least one selected from the group consisting of K + is preferred. M 2’ contains at least one element selected from the group consisting of Group 4 elements, Group 13 elements, and Group 14 elements, among which Si and Al are preferred. b’ satisfies 0 < b’ < 0.2, c’ is 2 ’ 1-b’ Mn 4+ b’ F d’ the absolute value of the charge of the ion, and d’ satisfies 5 < d’ < 7. ) In this specification, in the formula representing the composition of the phosphor, before the colon (:) represents the molar ratio of each element in 1 mole of the host crystal and the phosphor composition, and after the colon (:) represents the activating element.

[0047] The light-emitting device of the second embodiment and the light-emitting device of the fourth embodiment include, as the first phosphor, a first nitride phosphor having a composition represented by the formula (1A). By including the first phosphor as a first nitride phosphor having a composition represented by the formula (1A), the correlated color temperature is 1950K or less, the full width at half maximum of the emission peak having the maximum emission intensity in the emission spectrum of the light-emitting device is 110 nm or less, and it is possible to more easily emit light with reduced glare where the first glare index Ls1 / L is 0.493 or less. Further, by including the first nitride having a composition represented by the formula (1A) as the first phosphor, it is possible to more easily emit light with reduced glare where the second glare index Ls2 / L is 1.082 or less. The light-emitting device of the second embodiment is the same as the light-emitting device of the first embodiment except that the first phosphor essentially includes a first nitride phosphor having a composition represented by the formula (1A). The light-emitting device of the fourth embodiment is the same as the light-emitting device of the third embodiment except that the first phosphor essentially includes a first nitride phosphor having a composition represented by the formula (1A). The light-emitting device of the second embodiment and the light-emitting device of the fourth embodiment preferably include at least one selected from the group consisting of a second nitride phosphor having a composition represented by the formula (1B) and a fluoride phosphor having a composition represented by the formula (1C) as the first phosphor.

[0048] The first phosphor may contain at least one phosphor selected from the group consisting of a fluorogermanate phosphor, a fourth nitride phosphor, and a first sulfide phosphor. The fluorogermanate phosphor has, for example, a composition represented by the following formula (1D). The fourth nitride phosphor has, for example, a composition represented by the following formula (1E). The first sulfide phosphor has, for example, a composition represented by the following formula (1F). (i-j)MgO·(j / 2)Sc2O3·kMgF2·mCaF2·(1-n)GeO2·(n / 2)M 3 2O3:Mn (1D) (In the formula (1D), M 3 is at least one selected from the group consisting of Al, Ga, and In. i, j, k, m, and n each satisfy 2≦i≦4, 0≦j<0.5, 0<k<1.5, 0≦m<1.5, and 0≦n<0.5.) M 4 v2 M 5 w2 Al 3-y2 Si y2 N z2 :M 6 (1E) (In the formula (1E), M 4 is at least one element selected from the group consisting of Ca, Sr, Ba, and Mg, M 5 is at least one element selected from the group consisting of Li, Na, and K, M 6 is at least one element selected from the group consisting of Eu, Ce, Tb, and Mn, and v2, w2, y2, and z2 each satisfy 0.80≦v2≦1.05, 0.80≦w2≦1.05, 0≦y2≦0.5, and 3.0≦z2≦5.0.) (Ca,Sr)S:Eu (1F) In this specification, in the formula indicating the composition of the phosphor, a plurality of elements described separated by a comma (,) mean that at least one of these plurality of elements is included in the composition, and two or more of the plurality of elements may be combined and included.)

[0049] The fluorogermanate phosphor having the composition represented by formula (1D) may have the composition represented by the following formula (1d). 3.5MgO·0.5MgF2·GeO2:Mn (1d)

[0050] The fourth nitride phosphor having the composition represented by formula (1E) may have the composition represented by the following formula (1e). M 4 v2 M 5 w2 M 6 x2 Al 3-y2 Si y2 N z2 (1e) (In formula (1e), M 4 , M 5 and M 6 are respectively synonymous with M 4 , M 5 and M 6 in formula (1E), v2, w2, y2 and z2 are respectively synonymous with v2, w2, y2 and z2 in formula (1E), and x2 satisfies 0.001 < x2 ≦ 0.1.)

[0051] The fluorogermanate phosphor, the fourth nitride phosphor, and the first sulfide phosphor have an emission peak wavelength in the range of 570 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 first sulfide phosphor have a full width at half maximum of the emission peak having the emission peak wavelength in the emission spectrum of the first phosphor of, for example, 5 nm or more and 100 nm or less, preferably 6 nm or more and 90 nm or less.

[0052] The light-emitting device of the first embodiment and the light-emitting device of the third embodiment may contain at least one type of first phosphor alone or may contain two or more types of first phosphors. By including the first phosphor, when used outdoors, the light-emitting device has a correlated color temperature of 1950 K or less that does not cause a sense of discomfort, an average color rendering evaluation number Ra of 51 or more as the color rendering property required for a light-emitting device used outdoors or a light-emitting device used indoors in a place close to outdoors, the full width at half maximum of the emission peak having the maximum emission intensity in the emission spectrum of the light-emitting device is 110 nm or less, and it can emit light with reduced glare where the first glare index Ls1 / L is 0.493 or less. Further, by including the above-described first phosphor, the light-emitting device has a correlated color temperature of 1950 K or less, an average color rendering evaluation number Ra of 51 or more, the full width at half maximum of the emission peak having the maximum emission intensity in the emission spectrum of the light-emitting device is 110 nm or less, the second glare index Ls2 / L is 1.082 or less, and it can emit light with reduced glare even when viewing a relatively wide area.

[0053] The light-emitting devices of the second embodiment and the fourth embodiment essentially include, as the first phosphor, a first nitride phosphor having a composition represented by formula (1A), and may include at least one phosphor selected from the group consisting of a second nitride phosphor having a composition represented by formula (1B), a fluoride phosphor represented by formula (1C), a fluoride phosphor having a composition represented by formula (1C'), a fluorogermanate phosphor having a composition represented by formula (1D), a fourth nitride phosphor having a composition represented by formula (1E), and a first sulfide phosphor having a composition represented by formula (1F). The first phosphor may contain a single phosphor of the first nitride phosphor having a composition represented by formula (1A) alone, or may contain two or more phosphors. By including the first phosphor essentially containing the first nitride phosphor, when used outdoors, the light-emitting device has a correlated color temperature of 1950 K or less that does not cause a sense of discomfort, the full width at half maximum of the emission peak having the maximum emission intensity in the emission spectrum of the light-emitting device is 110 nm or less, and it can emit light with reduced glare where the first glare index Ls1 / L is 0.493 or less. Further, by including the above-described first phosphor, the light-emitting device has a correlated color temperature of 1950 K or less, the full width at half maximum of the emission peak having the maximum emission intensity in the emission spectrum of the light-emitting device is 110 nm or less, the second glare index Ls2 / L is 1.082 or less, and it can emit light with reduced glare even when viewing a relatively wide area.

[0054] The light-emitting devices of the second embodiment and the fourth embodiment essentially include, as the first phosphor, a first nitride phosphor having a composition represented by formula (1A), and may include at least one phosphor selected from the group consisting of a fluorogermanate phosphor having a composition represented by formula (1D), a fluorogermanate phosphor having a composition represented by formula (1E), and a first sulfide phosphor having a composition represented by formula (1F).

[0055] When the first phosphor essentially contains a first nitride phosphor having a composition represented by the formula (1A), all of the first phosphors may be the first nitride phosphor. When the first phosphor essentially contains a first nitride phosphor having a composition represented by the formula (1A) and contains a first phosphor other than the first nitride phosphor having a composition represented by the formula (1A), the mass ratio of the first nitride phosphor in the first phosphor to the first phosphor other than the first nitride phosphor (first nitride phosphor / first phosphor other than the first nitride phosphor) may be in the range of 99 / 1 to 1 / 99, may be in the range of 98 / 2 to 10 / 90, or may be in the range of 95 / 5 to 30 / 70. The first phosphor other than the first nitride phosphor having a composition represented by the formula (1A) refers to at least one phosphor selected from the group consisting of a second nitride phosphor having a composition represented by the formula (1B), a fluoride phosphor represented by the formula (1C), a fluoride phosphor represented by the formula (1C'), a fluorogermanate phosphor having a composition represented by the formula (1D), a fluorogermanate phosphor having a composition represented by the formula (1E), and a first sulfide phosphor having a composition represented by the formula (1F).

[0056] The content of the first phosphor contained in the light-emitting device varies depending on the form of the light-emitting device and the like. When the first phosphor is contained in the wavelength conversion member of the light-emitting device, the wavelength conversion member preferably contains a phosphor and a light-transmitting material. The wavelength conversion member may include a wavelength conversion body containing a phosphor and a light-transmitting material. The total amount of the phosphor contained in the wavelength conversion member may be in the range of 10 parts by mass or more and 900 parts by mass or less, may be in the range of 15 parts by mass or more and 850 parts by mass or less, or may be in the range of 20 parts by mass or more and 800 parts by mass or less with respect to 100 parts by mass of the light-transmitting material. The total amount of the phosphor refers to the total amount of the first phosphor when only the first phosphor is contained in the light-emitting device and no other phosphor other than the first phosphor is contained. The total amount of the phosphor refers to the total amount of the first phosphor and the second phosphor when the first phosphor and the second phosphor are contained in the light-emitting device.

[0057] When the light-emitting device includes the second phosphor described below, the content of the first phosphor included in the light-emitting device is preferably in the range of 5% by mass or more and 95% by mass or less with respect to the total amount of the first phosphor and the second phosphor. If the content of the first phosphor included in the light-emitting device is in the range of 5% by mass or more and 95% by mass or less with respect to the total amount of the first phosphor and the second phosphor, the correlated color temperature is 1950 K or less, the full width at half maximum of the emission peak having the maximum emission intensity in the emission spectrum of the light-emitting device is 110 nm or less, and glare with a first glare index Ls1 / L of 0.493 or less can be reduced. The content of the first phosphor included in the light-emitting device may be in the range of 8% by mass or more and 80% by mass or less, may be in the range of 10% by mass or more and 70% by mass or less, or may be in the range of 11% by mass or more and 60% by mass or less with respect to the total amount of the first phosphor and the second phosphor.

[0058] Second phosphor The light-emitting device preferably includes a second phosphor having an emission peak wavelength in the range of 480 nm or more and less than 570 nm. The second phosphor is excited by the emission of a light-emitting element having an emission peak wavelength in the range of 400 nm or more and 490 nm or less, and emits light having an emission peak wavelength in the range of 480 nm or more and less than 570 nm. The second phosphor may have an emission peak wavelength in the range of 490 nm or more and 565 nm or less, or may have an emission peak wavelength in the range of 495 nm or more and 560 nm or less when excited by the light-emitting element. The full width at half maximum of the emission peak having the emission peak wavelength in the emission spectrum of the second phosphor is preferably in the range of 20 nm or more and 125 nm or less, may be in the range of 25 nm or more and 124 nm or less, or may be in the range of 30 nm or more and 123 nm or less. For example, for a light-emitting device used outdoors or indoors but in a place close to outdoors, having a correlated color temperature that is not uncomfortable, satisfying the color rendering properties required for a light-emitting device used outdoors or indoors but in a place close to outdoors, and emitting light with reduced glare, the full width at half maximum of the emission peak having the emission peak wavelength in the emission spectrum of the second phosphor is preferably within the above range.

[0059] The second phosphor preferably contains at least one selected from the group consisting of a rare earth aluminate phosphor having a composition represented by the following formula (2A) and a third nitride phosphor having a composition represented by the following formula (2B). Ln 1 3(Al 1-a Ga a )5O 12 :Ce (2A) (In formula (2A), Ln 1 is at least one element selected from the group consisting of Y, Gd, Tb, and Lu, and a satisfies 0 ≦ a ≦ 0.5.) La w Ln 2 x Si6N y :Ce z (2B) (In formula (2B), Ln 2 essentially contains at least one selected from the group consisting of Y and Gd, may contain at least one selected from the group consisting of Sc and Lu, and 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, 0.5 ≦ z ≦ 1.2, 1.80 < w + x < 2.40, 2.9 ≦ w + x + z ≦ 3.1.) The rare earth aluminate phosphor having the composition represented by formula (2A) and the third nitride phosphor having the composition represented by formula (2B) have a full width at half maximum of the emission peak having the emission peak wavelength in the emission spectrum of the phosphor of, for example, 90 nm or more, preferably 100 nm or more, more preferably 110 nm or more, and also, for example, 125 nm or less, preferably 124 nm or less, more preferably 123 nm or less.

[0060] The second 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, for example, strontium and is a phosphor activated with europium, and has, for example, a composition represented by the following formula (2C). The alkaline earth metal halosilicate phosphor contains at least, for example, calcium and chlorine and is a phosphor activated with europium, and has, for example, a composition represented by the following formula (2D). Sr4Al 14 O 25 :Eu (2C) (Ca,Sr,Ba)8MgSi4O 16 (F,Cl,Br)2:Eu (2D) In formula (2C), 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 (2C) and the alkaline earth metal halosilicate phosphor having the composition represented by formula (2D) 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 the composition represented by formula (2C) and the alkaline earth metal halosilicate phosphor having the composition represented by formula (2D) have a full width at half maximum of the emission peak having the emission peak wavelength in the emission spectrum of the phosphor of, for example, 30 nm or more, preferably 40 nm or more, more preferably 50 nm or more, and also, for example, 80 nm or less, preferably 70 nm or less.

[0061] The second phosphor may contain at least one phosphor selected from the group consisting of β-sialon phosphors, second sulfide phosphors, scandium-based phosphors, and alkaline earth metal silicate phosphors. The β-sialon 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). The scandium-based phosphor has, for example, a composition represented by the following formula (2G). The alkaline earth metal silicate phosphor has, for example, a composition represented by the following formula (2H) or a composition represented by the following formula (2J). Si 6-g Al g O g N 8-g :Eu(0 < g ≦ 4.2) (2E) (Sr,M 7 )Ga2S4:Eu (2F) (In formula (2F), M 7 is at least one element selected from the group consisting of Be, Mg, Ca, Ba, and Zn.) (Ca,Sr)Sc2O4:Ce (2G) (Ca,Sr)3(Sc,Mg)2Si3O 12 :Ce (2H) (Ca,Sr,Ba)2SiO4:Eu (2J)

[0062] The β-sialon phosphor, the second sulfide phosphor, the scandium-based phosphor, and the alkaline earth metal silicate phosphor have an emission peak wavelength in the range of 520 nm or more and less than 580 nm, preferably in the range of 525 nm or more and 565 nm or less. The β-sialon phosphor, the second sulfide phosphor, the scandium-based phosphor, and the alkaline earth metal silicate phosphor have a full width at half maximum of the emission peak having the emission peak wavelength in the emission spectrum of the second phosphor of, for example, 20 nm or more, preferably 30 nm or more, and also, for example, 120 nm or less, preferably 115 nm or less.

[0063] The second phosphor may contain at least one phosphor selected from the group consisting of a rare earth aluminate phosphor having a composition represented by formula (2A), a third nitride phosphor having a composition represented by formula (2B), an alkaline earth metal aluminate phosphor having a composition represented by formula (2C), an alkaline earth metal halosilicate phosphor having a composition represented by formula (2D), a β-sialon phosphor having a composition represented by formula (2E), a second sulfide phosphor having a composition represented by formula (2F), a scandium-based phosphor having a composition represented by formula (2G), an alkaline earth metal silicate phosphor having a composition represented by formula (2H), and an alkaline earth metal silicate phosphor having a composition represented by formula (2J). The second phosphor may contain at least one phosphor alone or two or more thereof.

[0064] The light-emitting device preferably emits light having a color deviation Duv, which is a deviation from the blackbody radiation locus, of -0.008 or more and +0.008 or less. The color deviation Duv is a deviation from the blackbody radiation locus of the light emitted from the light-emitting device and is measured in accordance with JIS Z8725. Even when the correlated color temperature is relatively low, such as 1950 K or less, if the color deviation Duv from the blackbody radiation locus (Duv = 0.000) on the CIE1931 chromaticity diagram is within the range of -0.008 or more and +0.008 or less, light that makes the color of the irradiated object natural and does not give a sense of discomfort is emitted from the light-emitting device. The light-emitting device preferably emits light having a color deviation Duv, which is a deviation from the blackbody radiation locus of 1950 K or less, within the range of -0.008 or more and +0.008 or less, more preferably within the range of -0.006 or more and +0.006 or less, and even more preferably within the range of -0.003 or more and +0.003 or less. When light having a color deviation Duv exceeding 0.008 from the blackbody radiation locus of 1950 K or less is emitted, the irradiated object may deviate from the natural color and give a sense of discomfort to humans.

[0065] Figure 3A is a diagram showing the spectral locus and the black body radiation locus (Duv = 0.000) within the pure purple locus on the CIE1931 chromaticity diagram, and the color deviation from the black body radiation locus. Figure 3B shows a partially enlarged view of Figure 3A, showing the black body radiation locus in the range where the x value of the chromaticity coordinates in the CIE1931 chromaticity diagram is 0.300 or more and 0.600 or less and the y value is 0.250 or more and 0.500 or less, and the color deviation from the black body radiation locus, the loci of Duv = -0.020, Duv = -0.010, Duv = -0.008, Duv = +0.008, Duv = +0.010, and Duv = +0.020. In Figure 3B, the straight lines intersecting the black body radiation locus (Duv = 0.000) are the isochromatic temperature lines at each correlated color temperature (CCT = 1700K, 1950K, 2000K, 2700K, 3000K, 4000K, 5000K, 6500K). When the color deviation of the mixed light emitted from the light emitting device is Duv = 0, there is no deviation from the black body radiation locus and it approximates the black body radiation locus.

[0066] The light emitting device preferably emits light such that the second emission luminance in the range of 650 nm or more and 750 nm or less is 50% or less with respect to the first emission luminance of 100% in the range of 400 nm or more and 750 nm or less. In the light emission of the light emitting device, the ratio of the second emission luminance in the range of 650 nm or more and 750 nm or less to the first emission luminance of 100% in the range of 400 nm or more and 750 nm or less is also referred to as Lp. When the ratio Lp of the second emission luminance to the first emission luminance of the light emission of the light emitting device is 50% or less, among the mixed light emitted from the light emitting device, the light of the red component is relatively less, and light that reduces glare without causing discomfort to humans and without reducing the luminance is emitted from the light emitting device. The ratio Lp of the second emission luminance to the first emission luminance of the light emission of the light emitting device may be 45% or less, may be 40% or less, may be 35% or less, or may be 30% or less. The ratio Lp of the second emission luminance to the first emission luminance of the light emission of the light emitting device may be 5% or more or may be 8% or more in order to emit light having good color rendering properties.

[0067] The ratio Lp of the second luminance to the first luminance of the light emission of the light-emitting device is derived by the following formula (8). The ratio Lp of the second luminance in the range of 650 nm or more and 750 nm or less to the first luminance of 100% in the range of 400 nm or more and 750 nm or less of the light emission of the light-emitting device indicates the ratio of the light of the long-wavelength red component in the mixed-color light emitted from the light-emitting device.

[0068]

Number

[0069] The light-emitting device preferably emits light with a first relative glare index (Ls1 / L) / (Ls10 / L0) of 99.9% or less. The first relative glare index (Ls1 / L) / (Ls10 / L0) refers to the ratio (%) of the first glare index Ls1 / L derived from the above formula (1) of a light-emitting device that emits light with a correlated color temperature of 1950 K or less, when the reference first glare index Ls10 / L0 is set to 100%. The reference first glare index Ls10 / L0 can be the lowest value of the first glare index among the light-emitting devices to be measured that emit light with a correlated color temperature exceeding 1950 K, as the reference first glare index Ls10 / L0. When the first relative glare index (Ls1 / L) / (Ls10 / L0) is 99.9% or less, glare can be reduced compared to a light-emitting device that emits light with a correlated color temperature exceeding 1950 K. The first relative glare index (Ls1 / L) / (Ls10 / L0) is preferably 20% or more. When light with a first relative glare index (Ls1 / L) / (Ls10 / L0) of less than 20% is emitted from the light-emitting device, although the effect of reducing glare becomes greater compared to a light-emitting device that emits light with a correlated color temperature exceeding 1950 K, the color balance of the light is disrupted and the color rendering property deteriorates. In order to satisfy the color rendering property required for luminaires used outdoors and reduce glare, the light-emitting device preferably emits light within the range where the first relative glare index (Ls1 / L) / (Ls10 / L0) is 20% or more and 99.9% or less. A light-emitting device that emits light with a correlated color temperature of 1950 K or less may have a first relative glare index (Ls1 / L) / (Ls10 / L0) within the range of 30% or more and 99.8% or less, 40% or more and 99.7% or less, 50% or more and 99.6% or less, 60% or more, 80% or more, 90% or more, or 95% or more.

[0070] The reference first glare index Ls10 / L0 of a light-emitting device that emits light with a correlated color temperature exceeding 1950 K can be derived by the following formula (9).

[0071]

Equation

[0072] The first relative glare index (Ls1 / L) / (Ls10 / L0) (%) can be derived by the following Equation (10).

[0073] [Number]

[0074] The light-emitting device preferably emits light with a second relative glare index (Ls2 / L) / (Ls20 / L0) of 99.9% or less. The second relative glare index (Ls2 / L) / (Ls20 / L0) refers to the ratio of the second glare index Ls2 / L derived from the following formula (2) of a light-emitting device that emits light with a correlated color temperature of 1950 K or less, when the reference second glare index Ls20 / L0 of a light-emitting device that emits light with a correlated color temperature exceeding 1950 K is set to 100%. The reference second glare index Ls20 / L0 can be the lowest numerical second glare index among the light-emitting devices to be measured that emit light with a correlated color temperature exceeding 1950 K. When the second relative glare index (Ls2 / L) / (Ls20 / L0) is 99.9% or less, glare can be reduced compared to a light-emitting device that emits light with a correlated color temperature exceeding 1950 K, even when viewing a relatively wide range of areas. The second relative glare index (Ls2 / L) / (Ls20 / L0) is preferably 20% or more. When light with a second relative glare index (Ls2 / L) / (Ls20 / L0) of less than 20% is emitted from the light-emitting device, the effect of reducing glare is greater than that of a light-emitting device that emits light with a correlated color temperature exceeding 1950 K considering a human viewing angle of 10 degrees when viewing a relatively wide range of areas, but the color balance of the light is disrupted and the color rendering property deteriorates. In order to satisfy the color rendering property required for luminaires used outdoors and reduce glare, the light-emitting device preferably emits light with a second relative glare index (Ls2 / L) / (Ls20 / L0) within the range of 20% or more and 99.9% or less. A light-emitting device that emits light with a correlated color temperature of 1950 K or less may have a second relative glare index (Ls2 / L) / (Ls20 / L0) within the range of 30% or more and 99.8% or less, 40% or more and 99.7% or less, 50% or more and 99.6% or less, 60% or more, 80% or more, 90% or more, or 95% or more.

[0075] The reference second glare index Ls20 / L0 considering a human viewing angle of 10 degrees when viewing a relatively wide range of areas of a light-emitting device that emits light with a correlated color temperature exceeding 1950 K can be derived by the following formula (11).

[0076]

Number

[0077] The second relative glare index (Ls2 / L) / (Ls20 / L0) (%) can be derived by the following Equation (12).

[0078]

Number

[0079] An example of the light-emitting device will be described with reference to the drawings. FIGS. 4 and 5 are schematic cross-sectional views showing the light-emitting device of the first configuration example.

[0080] As shown in FIG. 4, the light-emitting device 100 includes a light-emitting element 10 having a light emission peak wavelength in the range of 400 nm or more and 490 nm or less, and a first phosphor 71 that is excited by the light from the light-emitting element and emits light.

[0081] The light-emitting device 100 includes a molded body 41, a light-emitting element 10, and a wavelength conversion member 21. The molded body 40 is integrally formed with a first lead 2, a second lead 3, and a resin portion 42 containing a thermoplastic resin or a thermosetting resin. The molded body 41 forms a recess having a bottom surface and a side surface, and the light-emitting element 10 is placed on the bottom surface of the recess. The light-emitting element 10 has a pair of positive and negative electrodes, and the pair of positive and negative electrodes are electrically connected to the first lead 2 and the second lead 3 via wires 60, respectively. The light-emitting element 10 is covered by the wavelength conversion member 21. The wavelength conversion member 21 includes, for example, a phosphor 70 that converts the wavelength of light from the light-emitting element 10 and a light-transmitting material. The wavelength conversion member 21 also functions as a sealing member that covers the light-emitting element 10 and the phosphor 70 in the recess of the molded body 40. The phosphor 70 includes a first phosphor 71 that is excited by light from the light-emitting element and has an emission peak wavelength in the range of 570 nm or more and 680 nm or less. A part of the first lead 2 and the second lead 3 connected to the pair of positive and negative electrodes of the light-emitting element 10 is exposed outward of the package constituting the light-emitting device 100. Through these first lead 2 and second lead 3, the light-emitting device 100 can receive power supply from the outside and emit light.

[0082] As shown in FIG. 5, the light-emitting device 200 is the same as the light-emitting device 100 shown in FIG. 4 except that the phosphor 70 includes a second phosphor 72 having an emission peak wavelength in the range of 480 nm or more and 570 nm or less, and the same members are denoted by the same reference numerals.

[0083] In the light-emitting device of the first configuration example, the wavelength conversion member includes a phosphor and a light-transmissive material, and the light-transmissive material is preferably a resin. The light-transmissive material used for the wavelength conversion member 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. In addition to the phosphor and the light-transmissive material, the wavelength conversion member may contain a filler, a colorant, and a light diffusing material as needed. Examples of the filler include silicon dioxide, barium titanate, titanium oxide, and aluminum oxide. The content of other components other than the phosphor and the light-transmissive material contained in the wavelength conversion member is the total content of other components, and can be in the range of 0.01 parts by mass or more and 50 parts by mass or less with respect to 100 parts by mass of the light-transmissive material, and may be in the range of 0.1 parts by mass or more and 45 parts by mass or less, or may be in the range of 0.5 parts by mass or more and 40 parts by mass or less.

[0084] Manufacturing method of the light-emitting device of the first configuration example The manufacturing method of the light-emitting device of the first configuration example will be described. For details, reference can also be made to the disclosure of, for example, Japanese Patent Application Laid-Open No. 2010-062272. The manufacturing method of the light-emitting device preferably includes a step of preparing a molded body, a step of arranging a light-emitting element, a step of arranging a composition for a wavelength conversion member, and a step of forming a resin package. When a collective molded body having a plurality of recesses is used as the molded body, an individualization step of separating each resin package of each unit region may be included after the resin package forming step.

[0085] In the step of preparing the molded body, a plurality of leads are integrally molded using a thermosetting resin or a thermoplastic resin to prepare a molded body having a recess having a side surface and a bottom surface. The molded body may be a molded body composed of a collective base body including a plurality of recesses. In the step of arranging the light-emitting element, the light-emitting element is arranged on the bottom surface of the recess of the molded body, and the positive and negative electrodes of the light-emitting element are connected to the first lead and the second lead by wires. In the step of arranging the composition for the wavelength conversion member, the composition for the wavelength conversion member is arranged in the recess of the molded body. In the resin package molding step, the composition for the wavelength conversion member arranged in the recess of the molded body is cured to form a resin package, and a light emitting device is manufactured. When a molded body composed of an aggregate substrate including a plurality of recesses is used, after the resin package forming step, in the singulation step, each unit region of the aggregate substrate having a plurality of recesses is separated for each resin package, and individual light emitting devices are manufactured. As described above, the light emitting device of the first configuration example shown in FIG. 4 or FIG. 5 can be manufactured.

[0086] FIG. 6 is a schematic perspective view showing a light emitting device of a second configuration example. FIG. 7 is a schematic cross-sectional view showing the light emitting device of the second configuration example.

[0087] As shown in FIGS. 6 and 7, the light emitting device 300 includes a support 1, a light emitting element 10 disposed on the support 1, a wavelength conversion member 22 including a phosphor 70 disposed on the upper surface of the light emitting element 10, and a light reflecting member 43 disposed on the support 1 on the side of the wavelength conversion member 22 and the light emitting element 10. A sealing member 50 is provided on the upper surface of the wavelength conversion member 22. The sealing member 50 has a lens portion 51 that is circular in plan view and semi-spherical in cross-sectional view, and a flange portion 52 that extends to the outer peripheral side of the lens portion 51. The lens portion 51 is circular in plan view and semi-spherical in cross-sectional view. Further, a flange portion 52 is extended to the outer peripheral side of the lens portion 51.

[0088] The wavelength conversion member 22 is formed larger than the light-emitting element 10 in a plan view. Further, a light-transmissive member 30 that contacts the side surface of the light-emitting element 10 and a part of the wavelength conversion member 22 is provided between the side surface of the light-emitting element 10 and the light reflection member 43. The light-transmissive member 30 includes a light-transmissive bonding member 32 provided between the light-emitting element 10 and the wavelength conversion member 22. The light-transmissive bonding member 32 can be an adhesive that bonds the light-emitting element 10 and the wavelength conversion member 22. A part of this light-transmissive bonding member 32 may extend to a corner portion formed by the side surface of the light-emitting element 10 and the main surface on the light-emitting element 10 side of the wavelength conversion member 22. Further, as shown in FIG. 7, the cross-sectional shape of the extended light-transmissive bonding member 32 can also be an inverted triangle that spreads in the direction of the light reflection member 43. As the light-transmissive member 30 and the bonding member 32, a resin having light-transmissivity can be used. The support 1 is a member for mounting the light-emitting element 10, the sealing member 50, etc. on the upper surface. The support 1 includes an insulating base material and a conductive member 4 such as a wiring pattern for mounting the light-emitting element on the surface of the base material. The light reflection member 43 is a member for covering the light-transmissive member 30, the bonding member 32, and the wavelength conversion member 22. For details of the light-emitting device of the second configuration example and the manufacturing method of the light-emitting device of the second configuration example described later, for example, the disclosure of Japanese Patent Application Laid-Open No. 2020-57756 can also be referred to.

[0089] The wavelength conversion member of the light-emitting device of the second configuration example includes a phosphor and a light-transmissive material, similarly to the wavelength conversion member of the light-emitting device of the first configuration example. The phosphor includes a first phosphor that is excited by the light from the light-emitting element and has an emission peak wavelength in the range of 570 nm to 680 nm or less. The phosphor may include a second phosphor that is excited by the light from the light-emitting element and has an emission peak wavelength in the range of 480 nm or more and 570 nm or less. As the light-transmissive material, the same light-transmissive material as that used for the wavelength conversion member of the light-emitting device of the first configuration example can be used. Further, the wavelength conversion member of the light-emitting device of the second configuration example may include a filler, a colorant, and a light diffusing material as necessary, similarly to the wavelength conversion member of the light-emitting device of the first configuration example, in addition to the phosphor and the light-transmissive material.

[0090] Manufacturing Method of Light-Emitting Device of Second Configuration Example An example of a method for manufacturing a light-emitting device according to the second configuration example will be described. The method for manufacturing a light-emitting device according to the second configuration example includes a step of arranging light-emitting elements, a step of preparing a wavelength conversion member, a step of forming a light-transmitting member and a bonding member, a step of arranging a light-reflecting member, and a step of arranging a sealing member, and may include a singulation step of separating each unit region.

[0091] In the step of arranging the light-emitting elements, the light-emitting elements are flip-chip mounted on a previously prepared support. In the step of preparing the wavelength conversion member, a composition for a wavelength conversion member containing a phosphor and a light-transmitting material is cured to be previously formed in a plate shape, a sheet shape, or a layer shape, and is singulated into a size that can be arranged on the light-emitting elements to prepare a plate-shaped, sheet-shaped, or layer-shaped wavelength conversion member. In the step of forming the light-transmitting member and the bonding member, a light-transmitting adhesive is applied to the upper surface of the light-emitting element, and the wavelength conversion member is bonded to the upper surface of the light-emitting element. The adhesive protruding from the interface between the light-emitting element and the wavelength conversion member adheres and extends from the side surface of the light-emitting element to the periphery of the wavelength conversion member, is cured in a fillet shape, and the light-transmitting member and the bonding member are formed. In the step of arranging the light-reflecting member, on the upper surface of the support, a white resin is arranged and cured so as to cover the side surfaces of the wavelength conversion member and the light-transmitting member, and the light-reflecting member is arranged. Finally, a sealing member is arranged on the upper surfaces of the wavelength conversion member and the light-reflecting member. Thus, a light-emitting device according to the second configuration example can be manufactured.

[0092] FIG. 8 is a schematic perspective view showing a light-emitting device according to the third configuration example. FIG. 9 is a schematic cross-sectional view showing the light-emitting device according to the third configuration example.

[0093] As shown in FIGS. 8 and 9, the light-emitting device 400 has a substantially rectangular parallelepiped external shape. The light-emitting device 400 includes a light-emitting element 10, a covering member 44, and a wavelength conversion member 23 including a phosphor 70. A translucent member 33 that contacts the side surface of the light-emitting element 10 and a part of the wavelength conversion member 23 is provided between the side surface of the light-emitting element 10 and the covering member 44. The translucent member 33 can be an adhesive that joins the light-emitting element 10 and the wavelength conversion member 23. The covering member 44 is disposed so as to cover the lower surface of the light-emitting element 10, the electrodes 12p and 12n, the side surface of the translucent member 33, and the lower surface of the wavelength conversion member 23. The covering member 44 is light-reflective and directly or indirectly covers the side surface of the light-emitting element 10. The outer surface of the covering member 44 and the side surface of the wavelength conversion member 23 constitute the side surface of the light-emitting device 400. It is preferable that the outer surface of the covering member 44 and the side surface of the wavelength conversion member 23 be the same surface. The covering member 44 covers the light-emitting device 10 such that at least a part of each of the pair of electrodes 12p and 12n is exposed. The lower surface of the covering member 44 constitutes a part of the lower surface of the light-emitting device 400. For details of the light-emitting device and its manufacturing method according to the third configuration example, reference can also be made to the disclosure of Japanese Patent Application Laid-Open No. 2019-9429, for example.

[0094] Manufacturing method of the light-emitting device according to the third configuration example The outline of the manufacturing method of the light-emitting device according to the third configuration example will be described. The manufacturing method of the light-emitting device according to the third configuration example includes a step of preparing a wavelength conversion member, a step of arranging a translucent member and a light-emitting element, a step of forming a translucent member, and a step of forming a covering member, and may include an electrode exposure step after the step of forming the covering member, and may include a singulation step of separating each unit region.

[0095] In the preparation step of the wavelength conversion member, a composition for the wavelength conversion member containing a phosphor and a light-transmitting material is cured and previously formed into a plate shape, sheet shape, or layer shape. In the step of arranging the light-transmitting member and the light-emitting element, a light-transmitting adhesive is applied to the upper surface of the wavelength conversion member, and the light-emitting element is arranged. In the step of forming the light-transmitting member, the adhesive protruding from the interface between the light-emitting element and the wavelength conversion member adheres and extends from the side surface of the light-emitting element to the periphery of the wavelength conversion member, is cured in a fillet shape, and the light-transmitting member is formed. In the step of forming the covering member, the covering member is formed on the wavelength conversion member so as to embed the light-emitting element. By removing a part of the covering member, the electrodes of the light-emitting element are exposed. If necessary, it is cut and separated for each unit area. Thus, the light-emitting device of the third configuration example can be manufactured.

[0096] Luminaire The luminaire may include at least one of the above-described light-emitting devices. The luminaire is configured to include the above-described light-emitting device, and may further include a reflecting member, a protecting member, an accessory device for supplying power to the light-emitting device, and the like. The luminaire may include a plurality of light-emitting devices. When the luminaire includes a plurality of light-emitting devices, it may include a plurality of the same light-emitting devices, or may include a plurality of light-emitting devices having different forms. Further, it may include a driving device capable of driving a plurality of light-emitting devices individually to adjust the brightness and the like of each light-emitting device. The usage form of the luminaire may be any of a direct-attached type, an embedded type, a suspended type, and the like. The luminaire may be a luminaire assumed for outdoor installation such as a street lamp, a harbor or a tunnel, or may be a luminaire assumed for outdoor use such as a headlight, a flashlight, or a portable lantern using an LED, or may be a luminaire installed indoors or in a place close to the outdoors such as near a window.

[0097] Street lamp The street lamp only needs to be provided with at least one kind of the above-described light-emitting device. FIG. 10 is a diagram showing an example of a street lamp. The street lamp 1000 includes a pole P installed on a sidewalk W or a roadway C and a support portion S of the light-emitting device Le. The support portion S is provided with a light-transmitting portion T that covers the periphery of the light-emitting device Le and transmits at least a part of the light emitted by the light-emitting device Le such as acrylic, polycarbonate, or glass. The street lamp 1000 can illuminate from a high place to a low place by the light-emitting device Le installed on the support portion S integrated with the pole P. The street lamp is not limited to the example shown in FIG. 10.

[0098] The street lamp may be not only a pole-type street lamp provided with a pole whose height of the support portion can be arbitrarily set, but also a bracket-type street lamp that supports the support portion with a bracket instead of a pole, a floodlight-type street lamp that illuminates from below to above, or a landscape material incorporation-type street lamp incorporated into landscape materials such as columns and blocks.

Embodiment

[0099] Hereinafter, the present invention will be specifically described with reference to embodiments. The present invention is not limited to these embodiments.

[0100] The following first phosphor and / or second phosphor were used for the light-emitting devices of each example and comparative example.

[0101] First phosphor As the first phosphor, as shown in Table 1, the first nitride phosphor BSESN-1 having different emission peak wavelengths and full widths at half maximum and included in the composition represented by formula (1A), and the second nitride phosphor SCASN-2, SCASN-3, SCASN-6 included in the composition represented by formula (1B), the fluoride phosphor KSF included in the composition represented by formula (1C), and the second nitride phosphor CASN included in the composition represented by formula (1B) (where q = 0 in formula (1B)) were prepared.

[0102] Second phosphor As the second phosphor, as shown in Table 2, a rare earth aluminate phosphor LAG having different emission peak wavelengths and full widths at half maximum and included in the composition represented by the formula (2A), Y3(Al,Ga)5O 12 :Ce, a rare earth aluminate phosphor G-YAG1 included in the composition represented by the formula (2A), and Y3Al5O 12 :Ce (where 0 < a ≦ 0.5) of the rare earth aluminate phosphor G-YAG1, and Y3Al5O 12 :Ce of the rare earth aluminate phosphors YAG1 and YAG3 included in the composition represented by the formula (2A) were prepared.

[0103] Measurement of the emission spectrum of the phosphor For each phosphor, using a quantum efficiency measurement device (QE-2000, manufactured by Otsuka Electronics Co., Ltd.), light with an excitation wavelength of 450 nm was irradiated onto each phosphor, and the emission spectrum at room temperature (about 25°C) was measured. The emission peak wavelength and full width at half maximum were measured from each emission spectrum. The results are shown in Table 1 and Table 2.

[0104]

Table 1

[0105]

Table 2

[0106] Example 1 The light-emitting device of the second configuration example was manufactured. The light-emitting device of the second configuration example can be referred to FIGS. 6 and 7.

[0107] Step of arranging the light-emitting element For the support 1, a ceramic substrate made of aluminum nitride was used. For the light-emitting element 10, a light-emitting element 10 in which a nitride semiconductor layer having an emission peak wavelength of 450 nm was laminated was used. The size of the light-emitting element 10 was a substantially square planar shape of about 1.0 mm square and a thickness of about 0.11 mm. The light-emitting element was arranged such that the light-emitting surface faced the sealing member side, and flip-chip mounted using bumps made of a conductive member 4 made of Au.

[0108] Preparation step of wavelength conversion member A silicone resin was used as the light-transmitting material constituting the wavelength conversion member 22. The first phosphor and the second phosphor were the phosphors shown in Table 3. The composition for the wavelength conversion member was formulated such that the total amount of the phosphor 70 and the blending ratio of the first phosphor and the second phosphor were the amounts shown in Table 3 so that the correlated color temperature of the mixed color light of the light from the light-emitting element 10 and the light of the phosphor 70 containing the first phosphor and the second phosphor was around 1900K with respect to 100 parts by mass of the light-transmitting material. The composition for the wavelength conversion member was formulated by blending 2 parts by mass of aluminum oxide as a filler with respect to 100 parts by mass of the silicone resin. Next, the prepared composition for the wavelength conversion member was heated at 180°C for 2 hours and cured into a sheet shape to prepare a sheet-shaped wavelength conversion member 22 that was about 0.1 mm larger in length and width than the planar shape of the light-emitting element 10, had a substantially square planar shape of about 1.6 mm on each side, and had a thickness of about 150 μm and was individualized.

[0109] Formation step of light-transmitting member and bonding member A phenyl silicone resin, which is a light-transmitting adhesive, was applied to the upper surface of the light-emitting element 10, the wavelength conversion member 22 was bonded, and a light-transmitting adhesive was further applied to the interface between the light-emitting element 10 and the wavelength conversion member 22 and cured at 150°C for 4 hours to form a light-transmitting member 30 and a bonding member 32 that were cured in a fillet shape so as to extend from the side surface of the light-emitting element 10 to the periphery of the wavelength conversion member 22.

[0110] Arrangement step of light reflection member As a composition for the light reflection member, a composition for the light reflection member containing a dimethyl silicone resin and titanium oxide particles having an average particle diameter (catalog value) of 0.28 μm and containing 60 parts by mass of titanium oxide particles with respect to 100 parts by mass of the dimethyl silicone resin was prepared. On the upper surface of the support 1, it was arranged in the composition for the light reflection member, which is a white resin, so as to cover the side surfaces of the wavelength conversion member 22 and the light-transmitting member 30, and cured to form the light reflection member 43.

[0111] Arrangement step of sealing member Finally, a sealing member 50 including a lens portion 51 that is circular in plan view and semi-spherical in cross-sectional view formed by curing a phenyl silicone resin, and a flange portion 52 extending to the outer peripheral side of the lens portion 51 is disposed, and a light-emitting device 300 of the second configuration example that emits light having a correlated color temperature of 1950 K or less is manufactured.

[0112] Examples 2 and 3 A light-emitting device of the second configuration example was manufactured. The light-emitting device of the second configuration example can be referred to in FIGS. 6 and 7. In the step of preparing the wavelength conversion member, except that a composition for a wavelength conversion member containing the first phosphor and the second phosphor is prepared such that the total amount of the phosphor 70 and the blending ratio of the first phosphor and the second phosphor are the amounts shown in Table 3 so that the correlated color temperature of the mixed color light of the light from the light-emitting element 10 and the light of the phosphor 70 containing the first phosphor and the second phosphor becomes around 1800 K with respect to 100 parts by mass of the translucent material, a light-emitting device 300 of the second configuration example that emits light having a correlated color temperature of 1950 K or less was manufactured in the same manner as in Example 1.

[0113] Comparative Example 1 A light-emitting device of the second configuration example was manufactured. The light-emitting device of the second configuration example can be referred to in FIGS. 6 and 7. In the step of preparing the wavelength conversion member, except that a composition for a wavelength conversion member containing the first phosphor and the second phosphor is prepared such that the total amount of the phosphor 70 and the blending ratio of the first phosphor and the second phosphor are the amounts shown in Table 3 so that the correlated color temperature of the mixed color light of the light from the light-emitting element 10 and the light of the phosphor 70 containing the first phosphor and the second phosphor becomes around 2200 K with respect to 100 parts by mass of the translucent material, a light-emitting device 300 of the second configuration example that emits light having a correlated color temperature of 2200 K or more was manufactured in the same manner as in Example 1.

[0114] Example 4 A light-emitting device 100 of the first configuration example was manufactured. The light-emitting device 100 of the first configuration example includes only the first phosphor 71 and does not include the second phosphor, and can be referred to in FIG. 4. The light-emitting element 10 used was a light-emitting element 10 in which a nitride semiconductor layer having a light-emitting peak wavelength of 450 nm was laminated. The size of the light-emitting element 10 was a substantially square planar shape of about 700 mm on each side and a thickness of about 200 mm. As the first lead 2 and the second lead 3, a lead frame was used, and the first lead 2 and the second lead 3 were integrally formed using an epoxy resin to prepare a molded body 41 having a recess having a side surface and a bottom surface. The light-emitting element 10 was disposed on the bottom surface of the recess of the molded body 41, and the positive and negative electrodes of the light-emitting element 10 were connected to the first lead 2 and the second lead 3 by an Au wire 60. A silicone resin was used as the translucent material constituting the wavelength conversion member 21. Two types of first phosphors, BSESN1 and SCASN3 shown in Table 3, were used as the first phosphors, and the mass ratio of BSESN1 to SCASN3 (BSESN1 / SCASN3) was 90.5 / 9.5. The composition for the wavelength conversion member contained light from the light-emitting element 10 and light of the phosphor 70 containing the first phosphor 71 and not containing the second phosphor, and the first phosphor 71 was blended as shown in Table 3 so that the correlated color temperature of the mixed color light was close to 1850 K. The composition for the wavelength conversion member was blended with 2 parts by mass of aluminum oxide as a filler with respect to 100 parts by mass of the silicone resin. Next, the prepared composition for the wavelength conversion member was filled into the recess of the molded body 41. The composition for the wavelength conversion member filled in the recess of the molded body 41 was heated at 150° C. for 3 hours to be cured, and a resin package provided with the wavelength conversion member 21 containing the first phosphor 71 was formed, and the light-emitting device 100 of the first configuration example that emits light having a correlated color temperature of 1950 K or less was manufactured.

[0115] Example 5 The light-emitting device 200 of the first configuration example was manufactured. The light-emitting device 200 of the first configuration example can refer to FIG. 5 including the first phosphor 71 and the second phosphor 72. A phenyl silicone resin was used as the translucent material constituting the wavelength conversion member 21. The phosphors shown in Table 3 were used as the first phosphor 71 and the second phosphor 72. The composition for a wavelength conversion member was formulated with a first phosphor 71 and a second phosphor 72 as shown in Table 3 such that the correlated color temperature of the mixed color light of the light from the light-emitting element 10 and the light of the phosphor 70 containing the first phosphor 71 and the second phosphor 72 would be close to 1850 K with respect to 100 parts by mass of the translucent material. The composition for a wavelength conversion member was also formulated with 15 parts by mass of silicon dioxide as a filler with respect to 100 parts by mass of the phenyl silicone resin. Next, the prepared composition for a wavelength conversion member was filled into the recess of the molded body 41. The composition for a wavelength conversion member filled in the recess of the molded body 41 was heated at 150 °C for 4 hours to be cured, thereby forming a resin package including a wavelength conversion member 21 containing the first phosphor 71 and the second phosphor 72, and manufacturing a light-emitting device 200 of the first configuration example that emits light with a correlated color temperature of 1950 K or less.

[0116] Example 6 A light-emitting device 400 of the third configuration example was manufactured. The light-emitting device of the third configuration example can be referred to with reference to FIGS. 8 and 9.

[0117] Preparation step of the wavelength conversion member A silicone resin was used as the translucent material constituting the wavelength conversion member 23. The first phosphor and the second phosphor used were the phosphors shown in Table 3. The composition for a wavelength conversion member was formulated with the first phosphor and the second phosphor such that the total amount of the phosphor 70 and the blending ratio of the first phosphor and the second phosphor would be the amounts shown in Table 3 so that the correlated color temperature of the mixed color light of the light from the light-emitting element 10 and the light of the phosphor 70 containing the first phosphor and the second phosphor would be close to 1850 K with respect to 100 parts by mass of the translucent material. The composition for a wavelength conversion member was also formulated with 2 parts by mass of aluminum oxide as a filler with respect to 100 parts by mass of the silicone resin. Next, the prepared composition for a wavelength conversion member was heated at 180 °C for 2 hours to be cured into a sheet shape, thereby preparing a sheet-shaped wavelength conversion member 22.

[0118] Arrangement step of the translucent member and the light-emitting element A phenyl silicone resin, which is a light-transmissive adhesive, was applied to the upper surface of the wavelength conversion member 23, and the same light-emitting element 10 as in Example 1 was bonded. Further, a light-transmissive adhesive was applied to the interface between the light-emitting element 10 and the wavelength conversion member 23 and cured at 150 °C for 4 hours to form a cured light-transmissive member 33 in a fillet shape extending from the side surface of the light-emitting element 10 to the periphery of the wavelength conversion member 23.

[0119] Forming step of the coating member As a composition for the coating member, a composition for the coating member containing a phenyl silicone resin and titanium oxide particles having an average particle diameter (catalog value) of 0.25 μm and containing 60 parts by mass of titanium oxide particles with respect to 100 parts by mass of the phenyl silicone resin was prepared. On the upper surface of the wavelength conversion member 23, it was placed in the composition for the coating member, which is a white resin, so as to cover the side surfaces of the wavelength conversion member 23 and the light-transmissive member 33 and embed the light-emitting element 10, and cured to form the coating member 44. By removing a part of the coating member 44, the electrodes 12p and 12n of the light-emitting element 10 were exposed. It was diced so as to be approximately 0.350 mm larger in both length and width than the planar shape of the light-emitting element 10, having a substantially square planar shape of about 1.7 mm on each side, and the total thickness including the wavelength conversion member 33 and the coating member 44 was about 350 μm, and a light-emitting device 400 of the third configuration example that emits light with a correlated color temperature of 1950 K or less was manufactured.

[0120] Comparative Examples 2 and 3 A light-emitting device 200 of the first configuration example was manufactured. The light-emitting device 200 of the first configuration example includes a first phosphor 71 and a second phosphor 72, and reference can be made to FIG. 5. In the step of preparing the wavelength conversion member, except that a composition for the wavelength conversion member containing the first phosphor 71 and the second phosphor 72 was prepared such that the total amount of the phosphor 70 and the blending ratio of the first phosphor 71 and the second phosphor 72 were the amounts shown in Table 3 so that the correlated color temperature of the mixed-color light of the light from the light-emitting element 10 and the light of the phosphor 70 including the first phosphor 71 and the second phosphor 72 became close to 1950 with respect to 100 parts by mass of the light-transmissive material, a light-emitting device 200 of the first configuration example that emits light with a correlated color temperature exceeding 1950 K and becoming 2000 K or less was manufactured in the same manner as in Example 5.

[0121] For each light-emitting device, the following measurements were performed. The results are shown in Table 3.

[0122] Emission spectrum of the light-emitting device For each light-emitting device, the emission spectrum was measured using an optical measurement system combining a spectro-radiometer (PMA-12, manufactured by Hamamatsu Photonics K.K.) and an integrating sphere. The measurement of the emission spectrum of each light-emitting device was performed at room temperature (20°C to 30°C). Figures 11 to 16 show the emission spectra (spectral radiance) S(λ) of each light-emitting device. Figures 11 to 16 show the emission spectra of each light-emitting device when the luminance L derived from the above formula (4) of each light-emitting device was set to the same numerical value.

[0123] Chromaticity coordinates (x, y), correlated color temperature (K), color deviation Duv, general color rendering index Ra, special color rendering index R9, full width at half maximum From the emission spectrum of each light-emitting device, the chromaticity coordinates (x value, y value) on the CIE chromaticity diagram of CIE1931, the correlated color temperature (CCT: K) and the color deviation Duv in accordance with JIS Z8725, and the general color rendering index Ra, the special color rendering index R9, and the full width at half maximum in accordance with JIS Z8726 were measured.

[0124] Ratio Lp of the second radiance to the first radiance Based on the above formula (4), from the emission spectrum (spectral radiance) S(λ) of each light-emitting device, the ratio Lp (%) of the second radiance in the range of 650 nm or more and 750 nm or less was calculated with the first radiance in the range of 400 nm or more and 750 nm or less being 100%.

[0125] First glare index Ls1 / L For each light-emitting device, the measured emission spectrum (spectral radiance) S(λ), the spectral sensitivity Gs(λ) of the human S cone obtained from Figure 1A, and the CIE-defined photopic standard relative luminosity curve V(λ) of a human obtained from Figure 1B were incorporated into the above formula (1) to obtain the first glare index Ls1 / L of each light-emitting device.

[0126] First relative glare index (Ls1 / L)(Ls10 / L0) Among the light-emitting devices of Comparative Examples 1 to 3 that emit light with a correlated color temperature exceeding 1950K, the first glare index Ls1 / L of the light-emitting device of Comparative Example 2, which has the lowest first glare index Ls1 / L, was used as the reference first glare index Ls10 / L0. The first relative glare index (Ls1 / L) / (Ls10 / L0), which is the ratio of the first glare index Ls1 / L of each light-emitting device to the reference first glare index Ls10 / L0, was calculated based on Equation (10).

[0127] Second glare index Ls2 / L For each light-emitting device, each emission spectrum (spectral radiance) S(λ) measured, the spectral sensitivity Gs(λ) of the human S cone obtained from FIG. 1A, and the photopic standard visual sensitivity curve V 10 (λ) and the photopic standard visual sensitivity curve V(λ) of humans defined by the CIE were incorporated into Equation (2) to obtain the second glare index Ls2 / L of each light-emitting device.

[0128] Second relative glare index (Ls2 / L)(Ls20 / L0) Among the light-emitting devices of Comparative Examples 1 to 3 that emit light with a correlated color temperature exceeding 1950K, the second glare index of the light-emitting device of Comparative Example 3, which has the lowest numerical value of the second glare index Ls2 / L, was used as the reference second glare index Ls20 / L0. The second relative glare index (Ls2 / L) / (Ls20 / L0), which is the ratio of the second glare index Ls2 / L of each light-emitting device to the reference second glare index Ls20 / L0, was calculated based on Equation (12).

[0129]

Table 3

[0130] As shown in Table 1, the light-emitting devices according to Examples 1 to 6 had a correlated color temperature of 1950 K or less, and emitted light with a correlated color temperature similar to or slightly lower than that of light emitted by, for example, a high-pressure sodium lamp. When the light-emitting devices of Examples 1 to 6 were used as a light source for a luminaire used outdoors, for example, even when the light-emitting device was used as an alternative to a high-pressure sodium lamp, light was emitted such that the color tone of the irradiated object was natural and did not give a sense of discomfort. Further, in the light-emitting devices according to Examples 1 to 6, the full width at half maximum of the emission peak having the maximum emission intensity in the emission spectrum was in the range of 3 nm or more and 110 nm or less. Further, the emission peak wavelength in the emission spectrum of the light-emitting device was in the range of 570 nm or more and 680 nm or less. Since the full width at half maximum of the emission peak having the maximum emission intensity in the emission spectrum of the light-emitting device was 3 nm or more and 110 nm or less, it was possible to suppress the component of light on the long wavelength side that was difficult for humans to perceive. Further, the light-emitting devices according to Examples 1 to 6 emitted light with a first glare index Ls1 / L derived from the above formula (1) of 0.493 or less, and the glare was reduced. Further, the light-emitting measures according to Examples 1 to 6 emitted light with a second glare index Ls2 / L of 1.082 or less, and the glare was reduced even when considering a viewing angle of 10 degrees when viewing a relatively wide range of regions.

[0131] The light-emitting devices according to Examples 1 to 6 emitted light with a color deviation Duv, which is the deviation from the blackbody radiation locus, of -0.001 or 0.000, and even when emitting light with a correlated color temperature of 1950 K or less, light was emitted from the light-emitting device such that the color tone of the irradiated object was natural and did not give a sense of discomfort.

[0132] The light-emitting devices according to Examples 1 to 6 emitted light with a ratio Lp of the second radiance in the range of 650 nm or more and 750 nm or less to the first radiance in the range of 400 nm or more and 750 nm or less of 50% or less. Among the mixed-color light emitted from the light-emitting devices according to Examples 1 to 6, light was emitted in which the light of the red component was relatively less and the glare was reduced without giving a sense of discomfort to humans.

[0133] The light-emitting devices according to Examples 1 to 6 had a first relative glare index (Ls1 / L) / (Ls10 / L0) of 99.6% or less, and were able to reduce glare more than light-emitting devices that emit light with a correlated color temperature exceeding 1950K.

[0134] The light-emitting devices according to Examples 1 to 6 had a second relative glare index (Ls2 / L) / (Ls20 / L0) of 99.6% or less, and were able to reduce glare more than light-emitting devices that emit light with a correlated color temperature exceeding 1950K even when viewing a relatively wide range of areas.

[0135] The light-emitting devices according to Examples 1 to 3, 5, and 6 had an average color rendering index Ra of 51 or more, and emitted light with sufficient color rendering properties even when illuminating, for example, roads with high traffic volume or many people coming and going.

[0136] The light-emitting device according to Example 4 had an average color rendering index Ra of 30 or more, and had sufficient color rendering properties for illuminating roads and the like.

[0137] The light-emitting devices according to Comparative Examples 1 to 3 emitted light with a correlated color temperature slightly higher than that of the light emitted by a high-pressure sodium lamp. When used as a light source for a luminaire used outdoors and replacing the high-pressure sodium lamp, for example, the color tone of the irradiated object did not look natural and there was a possibility of causing a sense of discomfort. Also, the light-emitting devices according to Comparative Examples 1 to 3 emitted light with a first glare index Ls1 / L exceeding 0.492, and the glare was not reduced. Further, the light-emitting devices according to Comparative Examples 1 to 3 emitted light with a second glare index Ls2 / L exceeding 1.082, and the glare was not reduced even when viewing a relatively wide range of areas.

[0138] As shown in FIGS. 11 and 12, the spectral radiant luminance of the light-emitting devices according to Examples 1 and 2 was lower than that of the light-emitting devices according to Comparative Examples 2 and 3 in the range of 400 nm to 500 nm on the short-wavelength side where the S cone photoreacts to light.

[0139] As shown in FIGS. 13 and 14, the spectral emission luminance of the light-emitting devices according to Examples 3 and 4 was lower than that of the light-emitting devices according to Comparative Examples 2 and 3 in the range of 400 nm to 550 nm on the short-wavelength side where the S cones photoreact.

[0140] As shown in FIG. 15, the spectral emission luminance of the light-emitting device according to Example 5 was lower than that of the light-emitting devices according to Comparative Examples 2 and 3 in the range of 450 nm to 500 nm on the short-wavelength side where the S cones photoreact.

[0141] As shown in FIG. 16, the spectral emission luminance of the light-emitting device according to Example 6 was lower than that of the light-emitting devices according to Comparative Examples 2 and 3 in the range of 400 nm to 470 nm on the shorter-wavelength side where the S cones photoreact.

Industrial Applicability

[0142] The light-emitting device according to one aspect of the present invention can be used as a light source for luminaires installed outdoors such as streetlights where glare reduction is required, luminaires installed outdoors such as in harbors and tunnels, headlights, flashlights, or portable lanterns using LEDs, and also for luminaires installed indoors in places close to the outdoors such as near entrances and exits and by windows.

Explanation of Reference Numerals

[0143] 1: Support, 2: First lead, 3: Second lead, 4: Conductive member, 10: Light-emitting element, 12p, 12n: Electrodes, 21, 22, 23: Wavelength conversion members, 30, 33: Light-transmissive members, 32: Light-transmissive joining member, 41: Molded body, 42: Resin part, 43: Light-reflecting member, 44: Coating member, 50: Sealing member, 51: Lens part, 52: Flange part, 60: Wire, 70: Phosphor, 71: First phosphor, 72: Second phosphor, 100, 200, 300, 400: Light-emitting devices, 1000: Streetlight, C: Roadway, Le: Light source, P: Pole, S: Support part, T: Light-transmitting part, W: Sidewalk.

Claims

1. A light emitting element having an emission peak wavelength in the range of 400 nm to 490 nm; a first phosphor having an emission peak wavelength in the range of 570 nm to 680 nm, The light emitting device has a correlated color temperature of 1950K or less and an average color rendering index Ra of 51 or more; When the luminance of the light emitted by the light emitting device in the range of 380 nm to 780 nm in consideration of the standard relative luminous efficiency of human photopic vision defined by the CIE (International Commission on Illumination) is L, and the first effective radiance of the light emitted by the light emitting device in the range of 380 nm to 780 nm in consideration of the standard relative luminous efficiency of human photopic vision and the sensitivity of the human S-cone is Ls1, a first glare index Ls1 / L of the first effective radiance Ls1 with respect to the luminance L, defined by the following formula (1), is 0.493 or less, and a first relative glare index (Ls1 / L) / (Ls1 0 / L 0 ) defined by the following formula (10), which is a ratio of the first glare index Ls1 / L to a reference first glare index Ls1 0 / L 0 of a light emitting device that emits light having a correlated color temperature of more than 1950 K, defined by the following formula (9), is A light emitting device that emits light in which the percent of the emission intensity is 95% or more and 99.9% or less. (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 λ range of 380 nm to 550 nm.) (In formula (9), S 0 (λ) is the spectral radiance of the light emitted from the light emitting device having a correlated color temperature of more than 1950 K, and V(λ) and Gs(λ) are defined as in formula (1).)

2. A light emitting element having an emission peak wavelength in the range of 400 nm to 490 nm; a first phosphor having an emission peak wavelength in the range of 570 nm to 680 nm, The first phosphor includes a first nitride phosphor having a composition represented by the following formula (1A): The light emitting device has a correlated color temperature of 1950 K or less; When the luminance of the light emitted by the light emitting device in the range of 380 nm to 780 nm in consideration of the standard relative luminous efficiency of human photopic vision defined by the CIE (International Commission on Illumination) is L, and the first effective radiance of the light emitted by the light emitting device in the range of 380 nm to 780 nm in consideration of the standard relative luminous efficiency of human photopic vision and the sensitivity of the human S-cone is Ls1, a first glare index Ls1 / L of the first effective radiance Ls1 with respect to the luminance L, defined by the following formula (1), is 0.493 or less, and a first relative glare index (Ls1 / L) / (Ls1 0 / L 0 ) defined by the following formula (10), which is a ratio of the first glare index Ls1 / L to a reference first glare index Ls1 0 / L 0 of a light emitting device that emits light having a correlated color temperature of more than 1950 K, defined by the following formula (9), is A light emitting device that emits light in which the percent of the emission intensity is 95% or more and 99.9% or less. M １ ２ Yes ５ N ８ :Eu (1A) (In formula (1A), M １ is an alkaline earth metal element including at least one selected from the group consisting of Ca, Sr, and Ba. (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 λ range of 380 nm to 550 nm.) (In formula (9), S 0 (λ) is the spectral radiance of the light emitted from the light emitting device having a correlated color temperature of more than 1950 K, and V(λ) and Gs(λ) are defined as in formula (1).)

3. A light emitting element having an emission peak wavelength in the range of 400 nm to 490 nm; a first phosphor having an emission peak wavelength in the range of 570 nm to 680 nm, The light emitting device has a correlated color temperature of 1950K or less and an average color rendering index Ra of 51 or more; When the luminance of the light emitted by the light emitting device in the range of 380 nm to 780 nm inclusive in consideration of the standard relative luminous efficiency of human photopic vision defined by the CIE (Commission Internationale de Illumination) is L, and a second effective radiance of the light emitted by the light emitting device in the range of 380 nm to 780 nm inclusive in consideration of the standard relative luminous efficiency of human photopic vision when the central visual field angle is shifted from −10 degrees to +10 degrees relative to the central visual field angle defined by the CIE and the sensitivity of human S-cones is Ls2, a second glare index Ls2 / L of the second effective radiance Ls2 with respect to the luminance L defined by the following formula (2) is 1.082 or less, The second radiance in the range of 650 nm to 750 nm is 50% or less relative to the first radiance in the range of 400 nm to 750 nm, A light emitting device that emits light in which a second relative glare index (Ls2 / L) / (Ls20 / L0) (%) defined by the following formula (12), which is a ratio of the second glare index Ls2 / L to a reference second glare index Ls20 / L0 of a light emitting device that emits light having a correlated color temperature of more than 1950K, as defined by the following formula (11), is 95% or more and 99.9% or less. (In formula (2), 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), Gs(λ) is the spectral sensitivity of the human S-cone in the wavelength λ range of 380 nm or more and 550 nm or less, and V １０ (λ) is the standard luminous efficiency curve for human photopic vision when the central visual field angle is shifted from -10 degrees to +10 degrees as specified by the CIE.) (In formula (11), S 0 (λ) is the spectral radiance of light emitted from a light emitting device having a correlated color temperature of more than 1950 K, and V(λ), V 10 (λ) and Gs(λ) are defined as in formula (2).)

4. A light emitting element having an emission peak wavelength in the range of 400 nm to 490 nm; a first phosphor having an emission peak wavelength in the range of 570 nm to 680 nm, The first phosphor comprises a first nitride phosphor having a composition represented by the following formula (1A): The light emitting device has a correlated color temperature of 1950 K or less; When the luminance of the light emitted by the light emitting device in the range of 380 nm to 780 nm inclusive taking into consideration the standard relative luminous efficiency of human photopic vision defined by the CIE (Commission Internationale de Illumination) is L, and the second effective radiance of the light emitted by the light emitting device in the range of 380 nm to 780 nm inclusive taking into consideration the standard relative luminous efficiency of human photopic vision when shifted from −10 degrees to +10 degrees with respect to the central visual field angle and the sensitivity of human S-cones defined by the CIE is Ls2, a second glare index Ls2 / L of the second effective radiance Ls2 with respect to the luminance L defined by the following formula (2) is 1.082 or less, and a second relative glare index (Ls2 / L) / (Ls2 0 / L 0 ) defined by the following formula (12) which is a ratio of the second glare index Ls2 / L to a reference second glare index Ls2 0 / L 0 of a light emitting device that emits light having a correlated color temperature of more than 1950 K defined by the following formula (11) is A light emitting device that emits light in which the percent of the emission intensity is 95% or more and 99.9% or less. M １ ２ Yes ５ N ８ :Eu (1A) (In formula (1A), M １ is an alkaline earth metal element including at least one selected from the group consisting of Ca, Sr, and Ba. (In formula (2), 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), Gs(λ) is the spectral sensitivity of the human S-cone in the wavelength λ range of 380 nm or more and 550 nm or less, and V １０ (λ) is the standard luminous efficiency curve for human photopic vision when the central visual field angle is shifted from -10 degrees to +10 degrees as specified by the CIE.) (In formula (11), S 0 (λ) is the spectral radiance of light emitted from a light emitting device having a correlated color temperature of more than 1950 K, and V(λ), V 10 (λ) and Gs(λ) are defined as in formula (2).)

5. The light emitting device according to claim 1 , wherein the first phosphor has an emission peak having an emission peak wavelength in an emission spectrum of the first phosphor, and a full width at half maximum of the emission peak is within a range of 3 nm to 120 nm.

6. The light emitting device according to claim 1, 3 or 5, wherein the first phosphor comprises at least one selected from the group consisting of a first nitride phosphor having a composition represented by the following formula (1A), a second nitride phosphor having a composition represented by the following formula (1B), a fluoride phosphor having a composition represented by the following formula (1C), and a fluoride phosphor having a composition represented by the following formula (1C') which has a different composition from that of formula (1C). M １ ２ Yes ５ N ８ :Eu (1A) (In formula (1A), 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 (1B) (In formula (1B), 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 ] (1C) (In formula (1C), 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’ ] (1C’) (In formula (1C'), 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.

7. The light emitting device according to claim 2, 4 or 5, wherein the first phosphor further comprises at least one selected from the group consisting of a second nitride phosphor having a composition represented by the following formula (1B), a fluoride phosphor having a composition represented by the following formula (1C), and a fluoride phosphor having a composition represented by the following formula (1C') which has a different composition from that of the following formula (1C). Sr ｑ Ca ｓ Al ｔ Yes ｕ N ｖ :Eu (1B) (In formula (1B), 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 ] (1C) (In formula (1C), 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, 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. A’ ｃ’ [M ２ ’ １－ｂ’ Mn ４＋ ｂ’ F ｄ’ ] (1C’) (In formula (1C'), 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.

8. The light emitting device according to claim 1 , further comprising a second phosphor having an emission peak wavelength in the range of 480 nm to 570 nm.

9. The light emitting device according to claim 8 , wherein the second phosphor has an emission peak having an emission peak wavelength in an emission spectrum of the second phosphor, and a full width at half maximum of the emission peak is within a range of 20 nm to 125 nm.

10. 10. The light emitting device according to claim 8 or 9, wherein the second phosphor comprises at least one selected from the group consisting of a rare earth aluminate phosphor having a composition represented by the following formula (2A) and a third nitride phosphor having a composition represented by the following formula (2B): <h2 style=";text-align:left;direction:ltr">Ln<h2 style=";text-align:left;direction:ltr"> １ <h2 style=";text-align:left;direction:ltr"> ３ <h2 style=";text-align:left;direction:ltr"> ((Al<h2 style=";text-align:left;direction:ltr"> １－ａ <h2 style=";text-align:left;direction:ltr"> 8a<h2 style=";text-align:left;direction:ltr"> ａ <h2 style=";text-align:left;direction:ltr"> )<h2 style=";text-align:left;direction:ltr"> ５ <h2 style=";text-align:left;direction:ltr"> O<h2 style=";text-align:left;direction:ltr"> １２ <h2 style=";text-align:left;direction:ltr"> :Ce(22A) (In formula (2A), Ln １ is at least one element selected from the group consisting of Y, Gd, Tb and Lu, and a satisfies 0≦a≦0.

5. La ｗ Ln ２ ｘ Si ６ N ｙ :Ce ｚ (2) (In formula (2B), 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.

11. The light emitting device according to claim 8 , wherein a content of the first phosphor with respect to a total amount of the first phosphor and the second phosphor is within a range of 5 mass % to 95 mass %.

12. The light emitting device according to claim 1 , which emits light having a color deviation Duv from the blackbody radiation locus in the range of −0.008 to +0.

008.

13. The light emitting device according to claim 1, 2, or any one of claims 4 to 12, which emits light in which the second radiance in the range of 650 nm to 750 nm is 50% or less relative to the first radiance in the range of 400 nm to 750 nm of 100%.

14. A lamp comprising the light emitting device according to any one of claims 1 to 13.

15. A street lamp comprising the light emitting device according to any one of claims 1 to 13.

Images