JP7670965B2 - Light emitting device and lamp having the same - Google Patents

Description

This disclosure relates to a light-emitting device and a lamp equipped with the same.

One example of a light-emitting device that uses a light-emitting element called a light-emitting diode (hereinafter also referred to as "LED") is a light-emitting device that combines a blue-emitting LED with a yellow-emitting phosphor. This is a light-emitting device that emits white light by mixing the blue light of the blue LED with the yellow light emitted by the phosphor excited by that light.

Light-emitting devices that combine a light-emitting element that emits blue light with a phosphor that emits yellow light have a high radiation intensity in the visible light range, and therefore have high luminous efficiency. Furthermore, there are cases where a light-emitting device with a high average color rendering index, which is an index of how the color of an irradiated object appears (color rendering properties), is required.

JIS Z8726 stipulates that the procedure for evaluating the color rendering of a light source is to perform a numerical calculation to determine the color difference ΔEi (i is an integer from 1 to 15) when a test color (R1 to R15) having a specified reflectance characteristic is measured using a test light source and a reference light source. Here, the upper limit of the color rendering index Ri (i is an integer from 1 to 15) is 100. In other words, the smaller the color difference between the test light source and the reference light source with the corresponding color temperature, the higher the color rendering.

In relation to the above, a light emitting device with good color reproducibility has been proposed, using an LED that emits blue light and two types of phosphors that emit light in the yellow to green range (see, for example, Patent Document 1).

Special Publication No. 2003-535477

Even if a visual target is illuminated using a light-emitting device with good color reproducibility, when the visual target is photographed by a camera such as a television camera and broadcast, and then displayed on a screen that receives the broadcast, the color reproducibility of the visual target as seen through the screen may not be maintained.

One aspect of the present disclosure is to provide a light-emitting device that can improve the color reproducibility of a visual object and a lamp equipped with the same.

The present disclosure encompasses the following aspects.
A first aspect is a light emitting device including a light emitting element having an emission peak wavelength in the range of 430 nm to 470 nm, and a fluorescent member, wherein the fluorescent member includes at least one rare earth aluminate phosphor selected from the group consisting of a first rare earth aluminate phosphor having a composition represented by the following formula (I) and a second rare earth aluminate phosphor having a composition included in the composition formula represented by the following formula (II), at least one fluoride phosphor selected from the group consisting of a first fluoride phosphor having a composition included in the composition formula represented by the following formula (III) and a second fluoride phosphor having a composition included in the composition formula represented by the following formula (IV), and at least two nitride phosphors selected from nitride phosphors having a composition included in the composition formula represented by the following formula (V), and the lighting consistency index TLCI (Television Lighting Consistency Index) recommended by the European Broadcasting Union (EBU) is 100%. The light emitting device has a TLCI value Qa of 90 or more and a Q10 value of 90 or more, as calculated by the TLCI Index-2012.
Lu ₃ Al ₅ O ₁₂ :Ce (I)
Y ₃ (Al _1-a Ga _a ) ₅ O ₁₂ :Ce (II)
(In formula (II), a satisfies 0≦a≦0.5.)
A _c [M ² _1-b Mn ⁴⁺ _b F _d ] (III)
(In formula (III), A includes at least one selected from the group consisting of K ⁺ , Li ⁺ , Na ⁺ , Rb ⁺ , Cs ⁺ and NH ₄ ⁺ ; M ² includes at least one element selected from the group consisting of Group 4 elements and Group 14 elements; b satisfies 0<b<0.2; 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' ] (IV)
(In formula (IV), A' includes at least one selected from the group consisting of K ⁺ , Li ⁺ , Na ⁺ , Rb ⁺ , Cs ⁺ and NH ₄ ⁺ ; M ² ' includes at least one element selected from the group consisting of Group 4 elements, Group 13 elements and Group 14 elements; b' satisfies 0<b'<0.2;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.)
Sr _q Ca _s Al _t Si _u N _v :Eu (V)
(In formula (V), 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.)

The second aspect is a lighting fixture equipped with the light-emitting device.

According to one aspect of the present disclosure, it is possible to provide a light-emitting device that can improve the color reproducibility of a visual object, and a lamp having the same.

1 is a schematic cross-sectional view illustrating an example of a light-emitting device according to an embodiment. FIG. 13 is a diagram showing the Q10 value of the light emitting devices according to Examples 1 to 6 and Comparative Examples 1 to 6 which emit light of each correlated color temperature. 1 is a diagram showing an emission spectrum of a light emitting device according to Example 1, an emission spectrum of a light emitting device according to Comparative Example 1, and a spectrum of a reference light source having a correlated color temperature of 6500 K. 13 is a diagram showing an emission spectrum of a light emitting device according to Example 2, an emission spectrum of a light emitting device according to Comparative Example 2, and a spectrum of a reference light source having a correlated color temperature of 5000 K. 13 is a diagram showing an emission spectrum of a light emitting device according to Example 3, an emission spectrum of a light emitting device according to Comparative Example 3, and a spectrum of a reference light source having a correlated color temperature of 4000K. 13 is a diagram showing the emission spectrum of a light emitting device according to Example 4, the emission spectrum of a light emitting device according to Comparative Example 4, and the spectrum of a reference light source having a correlated color temperature of 3500 K. 13 is a diagram showing an emission spectrum of a light emitting device according to Example 5, an emission spectrum of a light emitting device according to Comparative Example 5, and a spectrum of a reference light source having a correlated color temperature of 3000K. 13 is a diagram showing the emission spectrum of a light emitting device according to Example 6, the emission spectrum of a light emitting device according to Comparative Example 6, and the spectrum of a reference light source having a correlated color temperature of 2700 K.

The light-emitting device and the lamp including the same according to the present disclosure will be described below based on the embodiments. However, the embodiments shown below are intended to embody the technical idea of the present invention, and do not limit the present invention to the following. In this specification, the relationship between the color name and the chromaticity coordinate, and the relationship between the wavelength range of light and the color name of monochromatic light are in accordance with JIS Z8110. When multiple substances corresponding to each component are present in the composition, the content of each component in the composition means the total amount of the multiple substances present in the composition, unless otherwise specified. The average particle size of the phosphor is a value called the Fisher Sub Sieve Sizer's Number, and is measured using the air permeability method.

Light-emitting device The light-emitting device includes a light-emitting element having an emission peak wavelength in the range of 430 nm to 470 nm, and a fluorescent member. The fluorescent member includes at least one rare earth aluminate phosphor selected from the group consisting of a first rare earth aluminate phosphor having a composition included in the composition formula represented by the following formula (I) and a second rare earth aluminate phosphor having a composition included in the composition formula represented by the following formula (II), a fluoride phosphor including at least one selected from the group consisting of a first fluoride phosphor having a composition included in the composition formula represented by the following formula (III) and a second fluoride phosphor having a composition included in the composition formula represented by the following formula (IV), and at least two nitride phosphors selected from nitride phosphors having a composition included in the composition formula represented by the following formula (V). In addition, the light emitting device emits light having a Television Lighting Consistency Index (TLCI) value Qa of 90 or more and a Q10 value of 90 or more, as calculated according to the Television Lighting Consistency Index (TLCI)-2012 recommended by the European Broadcasting Union (EBU).

Lu ₃ Al ₅ O ₁₂ :Ce (I)
Y ₃ (Al _1-a Ga _a ) ₅ O ₁₂ :Ce (II)
A _c [M ² _1-b Mn ⁴⁺ _b F _d ] (III)
A'_c' [M ² '_1-b' Mn ⁴⁺ _b' F _d' ] (IV)
Sr _q Ca _s Al _t Si _u N _v :Eu (V)

In formula (II), a satisfies 0≦a≦0.5.
In formula (III), A includes at least one selected from the group consisting of K ⁺ , Li ⁺ , Na ⁺ , Rb ⁺ , Cs ⁺ and NH ₄ ⁺ , M ² includes at least one element selected from the group consisting of Group 4 elements and Group 14 elements, and A is preferably K ⁺ and M ² is preferably Si. b satisfies 0<b<0.2, 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. The composition included in the composition formula represented by formula (III) may be expressed as, for example, K ₂ SiF ₆ :Mn (hereinafter, also referred to as "KSF").
In formula (IV), A' includes at least one selected from the group consisting of K ⁺ , Li ⁺ , Na ⁺ , Rb ⁺ , Cs ⁺ , and NH4 ⁺ , ^M2 ' includes at least one element selected from the group consisting of Group ₄ elements, Group 13 elements, and Group 14 elements, A is preferably K ⁺ , and ^M2 is preferably Si and Al. b' satisfies 0<b'<0.2, c' is the absolute value of the charge of the [ ^M2'1 _-b'Mn4 ⁺ _{b'Fd '} ] ion, and d' satisfies 5<d'<7. An example of a composition that is included in the composition formula represented by formula (IV) and includes Si and Al is a composition also referred to as "KSAF".
In formula (V), q, s, t, u, and v satisfy the following conditions: 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. Examples of compositions included in the composition formula represented by formula (V) include (Sr,Ca)AlSiN ₃ :E
It is also sometimes written as CaAlSiN ₃ :u (hereinafter, also written as "SCASN"), and CaAlSiN 3 :Eu (hereinafter, also written as "CASN").

TLCI (also abbreviated as "Q")-2012 recommended by the EBU is an evaluation index of the color rendering of an irradiated object when the irradiated object is photographed, for example, by a television camera and broadcast, and the broadcast is displayed on a screen that receives the image. In addition, the above "Q" can be an evaluation index of the color rendering of an irradiated object when an image is photographed by a portable camera and the contents of the image are displayed on the portable camera screen, or when an image is photographed by a computer camera and the contents of the image are displayed on a computer display screen. The higher the TLCI value Q, the higher the color reproducibility. The TLCI value Q calculated by the TLCI-2012 recommended by the EBU is Q1 to Q24, and there is a test sample in which 24 color patches are arranged in four rows of six patches each. The value Qa is the average value of Q1 to Q18. The TLCI value Q calculated by TLCI-2012 is sometimes called the TLCI value Q. The upper limit of each of the TLCI Q1 to Q24 values is 100. The closer each of the TLCI Q1 to Q24 values is to 100, the better the color reproducibility of the image of the illuminated object displayed on the screen. The TLCI test sample includes grayscales Q19 to Q24, including the white value Q19, which is not included in the TLCI analysis. The TLCI value Q10 represents purple. The higher the value Qa, which is the average value of the TLCI Q1 to Q18, the more light is emitted that improves the color reproducibility of the visual object, regardless of how the visual object is viewed.

The light emitting device has the above-mentioned configuration, and suppresses the emission spectrum of the blue-violet to blue wavelengths in the range of 430 nm to 470 nm from being prominently high in intensity in the emission spectrum of the light emitting device, and can greatly improve the emission intensity of the emission spectrum in the wavelength region of yellow to green emission. In particular, the emission spectrum of the light emitting device is suppressed so that only the emission spectrum in the wavelength region of blue-violet to blue does not become prominently high in intensity, and the emission spectrum in the wavelength region of yellow to green emission is made closer to the reference light source, and the emission component of green emission with high luminosity can also be increased, so that it is possible to achieve excellent color rendering and high luminous efficiency. The light emitting device uses a red-emitting fluoride phosphor and two types of nitride phosphors, and can greatly improve the emission intensity around 650 nm in the emission spectrum of the light emitting device. The light emitting device can maintain high luminous efficiency by using a fluoride phosphor, and can emit light with a TLCI value Qa of 90 or more and a value Q10 of 90 or more by using two types of nitride phosphors. The light emitting device emits light having a TLCI value Qa of 90 or more, preferably emitting light having a value Qa of 91 or more, more preferably emitting light having a value Qa of 92 or more, and particularly preferably emitting light having a value Qa of 93 or more. The upper limit of the value Qa of the light emitted from the light emitting device is 100, and the light emitting device may emit light having a TLCI value Qa of 100 or less, or may emit light having a value Qa of 99 or less. The light emitting device emits light having a TLCI value Q10 of 90 or more, preferably emitting light having a value Q10 of 91 or more, more preferably emitting light having a value Q10 of 92 or more, and particularly preferably emitting light having a value Q10 of 93 or more. The upper limit of the value Q10 of the light emitted from the light emitting device is 100, and the light emitting device may emit light having a TLCI value Q10 of 100 or less, or may emit light having a value Q10 of 99 or less. Light emitting devices that emit white mixed light with high color rendering properties and are used for general lighting, etc., tend to have a TLCI value Q10 that is less than 90. When the TLCI value Q10 is a high value of 90 or more, the value Qa, which is the average value of Q1 to Q18 including the value Q10, also exhibits a high value of 90 or more and close to 100, and light with improved color reproducibility is emitted even when projected on a screen. The value Qa, which is the average value of Q1 to Q24 and Q1 to Q18 of the TLCI recommended by the EBU, is based on the TLCI-2012 ("TECH 3355 METHOD FOR THE ASSESSMENT OF THE COLORIMETRIC PROPERTIES OF LUMINAIRES THE TELEVISION LIGHTING CONSISTENCY INDEX (TLCI-2012) AND THE TELEVISION LUMINAIRE MATCHING FACTOR (TLMF-2013)" recommended by the EBU, European Broadcasting Corporation. Union, Geneva, March, 2017) can be calculated using the formula.

It is preferable that the light emitting device emits light that has excellent color rendering properties (hereinafter, also referred to as "color rendering properties").
The procedure for evaluating the color rendering of light emitted from a light source such as a light-emitting device is stipulated in JIS Z8726 as follows: test colors (R1 to R15) having a specified reflectance characteristic are measured using a test light source and a reference light source, and the color rendering index is calculated by numerically calculating the color difference ΔEi (i is an integer from 1 to 15) when the test light source and the reference light source having the corresponding color temperature are measured. The upper limit of the color rendering index Ri (i is an integer from 1 to 15) is 100. The smaller the color difference between the test light source and the reference light source having the corresponding color temperature, the closer the color rendering index is to 100 and the higher it becomes. Of the color rendering indexes, the average value of R1 to R8 is the average color rendering index (hereinafter also referred to as "Ra"), and R9 to R15 are the special color rendering indexes. Regarding color rendering, the CIE (International Commission on Illumination) published guidelines for the color rendering that fluorescent lamps should have in 1986. According to these guidelines, the preferable Ra depending on the place of use is 60 or more and less than 80 for factories where general work is performed, 80 or more and less than 90 for homes, hotels, restaurants, stores, offices, schools, hospitals, factories where precision work is performed, etc., and 90 or more for places where clinical tests where high color rendering is required, such as museums.

The light emitting device emits light with an Ra of, for example, 80 or more, preferably with an Ra of 90 or more, and more preferably with an Ra of 92 or more. In addition, the light emitting device preferably emits light with a higher R15 value, preferably with an R15 of 85 or more, more preferably with an R15 of 90 or more, even more preferably with an R15 of 92 or more, and particularly preferably with an R15 of 93 or more.

The light emitted by the light emitting device is a mixed color of the light from the light emitting element and the fluorescence emitted by each of the phosphors mentioned above, and can be, for example, light whose chromaticity coordinates defined in CIE 1931 are within the ranges of x = 0.20 to 0.50 and y = 0.20 to 0.50, or can be light whose chromaticity coordinates are within the ranges of x = 0.30 to 0.50 and y = 0.30 to 0.45, as defined in CIE 1931.
The correlated color temperature of the light emitted by the light emitting device can be, for example, 2000 K or more, and can also be 2500 K or more. The correlated color temperature can also be 7000 K or less.

A light emitting device 100, which is an example of a light emitting device, will be described with reference to the drawings.
The light emitting device 100 includes a light emitting element 10 of a gallium nitride compound semiconductor having an emission peak wavelength in the range of 430 nm to 470 nm, and a molded body 40 on which the light emitting element 10 is mounted. The molded body 40 is formed by integrally molding a first lead 20, a second lead 30, and a resin part 42 containing a thermoplastic resin or a thermosetting resin. The molded body 40 forms a recess having a bottom surface and a side surface, and the light emitting element 10 is mounted 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 20 and the second lead 30 via wires 60, respectively. The light emitting element 10 is covered with a fluorescent member 50. The fluorescent member 50 contains, for example, a rare earth aluminate fluorescent material 71, a fluoride fluorescent material 72, and two types of nitride fluorescent materials 73 as a fluorescent material 70 that converts the wavelength of light from the light emitting element 10, and a resin. The phosphor 70 contained in the fluorescent member 50 may include two or more types of phosphors.

The fluorescent member 50 not only converts the wavelength of the light emitted by the light-emitting element 10, but also functions as a member for protecting the light-emitting element 10 from the external environment. In FIG. 1, the phosphor 70 is unevenly distributed in the fluorescent member 50. By arranging the phosphor 70 close to the light-emitting element 10 in this manner, the light from the light-emitting element 10 can be efficiently wavelength-converted, resulting in a light-emitting device with excellent light-emitting efficiency. The arrangement of the fluorescent member 50 containing the phosphor 70 and the light-emitting element 10 is not limited to a form in which they are arranged close to each other, and the light-emitting element 10 and the phosphor 70 can be arranged with a gap between them in the fluorescent member 50, taking into account the effect of heat on the phosphor 70. In addition, by mixing the phosphor 70 in an almost uniform ratio throughout the fluorescent member 50, light with less color unevenness can be obtained.

The light-emitting element has a peak emission wavelength in the range of 430 nm to 470 nm, and from the viewpoint of luminous efficiency and color rendering, preferably has a peak emission wavelength in the range of 440 nm to 465 nm, more preferably has a peak emission wavelength in the range of 440 nm to 460 nm, further preferably has a peak emission wavelength in the range of 445 nm to 460 nm, and may have a peak emission wavelength in the range of 450 nm to 460 nm. Such a light-emitting element is used as an excitation light source to configure a light-emitting device that emits a mixed color light of the light from the light-emitting element and the fluorescence from the phosphor.

The full width at half maximum of the emission spectrum showing the maximum emission intensity of the light emitting element may be, for example, 30 nm or less.
As the light emitting element, it is preferable to use, for example, a semiconductor light emitting element using a nitride semiconductor. By using a semiconductor light emitting element as a light source, it is possible to obtain a light emitting device that is highly efficient, has high linearity of output relative to input, and is stable against mechanical shock.
In this specification, the full width at half maximum refers to a wavelength width in an emission spectrum where the emission intensity is 50% of the emission intensity at the emission peak wavelength showing the maximum emission intensity.

Phosphor The light emitting device contains at least one type of phosphor that absorbs a portion of the light emitted from the light emitting element and emits light of a different wavelength from the light emitted from the light emitting element, thereby enabling the light emitting device to increase its luminous flux while also increasing its TLCI value Qa.

Rare earth aluminate phosphor The first rare earth aluminate phosphor having a composition included in the composition formula represented by the formula (I) preferably includes a first rare earth aluminate phosphor having an emission peak wavelength in the range of 500 nm to 540 nm and a full width at half maximum in the range of 95 nm to 105 nm. The first rare earth aluminate phosphor having a composition included in the composition formula represented by the formula (I), and having an emission peak wavelength in the range of 500 nm to 540 nm and a full width at half maximum in the range of 95 nm to 105 nm, for example, is a rare earth aluminate phosphor represented as LAG.

The second rare earth aluminate phosphor having a composition included in the composition formula represented by the formula (II) preferably includes a third rare earth aluminate phosphor having an emission peak wavelength in the emission spectrum of the second rare earth aluminate phosphor in the range of 520 nm to 550 nm and a full width at half maximum in the range of 95 nm to 115 nm. The third rare earth aluminate phosphor included in the second rare earth aluminate phosphor having a composition included in the composition formula represented by the formula (II) and having an emission peak wavelength in the emission spectrum in the range of 520 nm to 550 nm and a full width at half maximum in the range of 95 nm to 115 nm can be a rare earth aluminate phosphor designated as GGAG1 or GGAG2, which has a different emission peak wavelength and full width at half maximum.

The second rare earth aluminate phosphor having a composition included in the composition formula represented by the formula (II) preferably includes a fourth rare earth aluminate phosphor having an emission peak wavelength in the emission spectrum of the second rare earth aluminate phosphor in the range of 535 nm to 555 nm and a full width at half maximum in the range of 100 nm to 120 nm. The fourth rare earth aluminate phosphor included in the second rare earth aluminate phosphor having a composition included in the composition formula represented by the formula (II) and having an emission peak wavelength in the emission spectrum in the range of 535 nm to 555 nm and a full width at half maximum in the range of 100 nm to 120 nm is exemplified by a rare earth aluminate phosphor designated as YAG.

Taking into consideration the luminous efficiency, the maximum excitation wavelength of the rare earth aluminate phosphor is preferably in the range of 380 nm to 490 nm, more preferably in the range of 430 nm to 470 nm, and even more preferably in the range of 440 nm to 460 nm.

The average particle size of the rare earth aluminate phosphor is, for example, in the range of 5 μm to 30 μm, preferably in the range of 20 μm to 25 μm, in consideration of the luminous intensity and the improvement of the workability in the manufacturing process of the light emitting device. The light emitting device may contain one type of rare earth aluminate phosphor alone, or may contain a combination of two or more types of rare earth aluminate phosphors with different compositions. Hereinafter, the average particle size of the phosphor refers to the cumulative 50% particle size (volume average particle size) in the volume-based particle size distribution measured by the laser diffraction particle size distribution measurement method. The volume average particle size can be measured using a laser diffraction particle size distribution measurement device (MASTER SIZER 3000, manufactured by MALVERN), and the catalog value may be used as long as it is the volume average particle size measured by the laser diffraction particle size distribution measurement method.

Fluoride phosphor The first fluoride phosphor having a composition included in the composition formula represented by the formula (III) preferably includes a first fluoride phosphor having an emission peak wavelength in the range of 620 nm to 640 nm in the emission spectrum of the first fluoride phosphor. An example of the first fluoride phosphor having a composition included in the composition formula represented by the formula (III), an emission peak wavelength in the range of 620 nm to 640 nm in the emission spectrum, and a full width at half maximum of 14 nm or less is a first fluoride phosphor represented as KSF.

The second fluoride phosphor having a composition included in the composition formula represented by formula (IV) preferably includes a second fluoride phosphor having an emission peak wavelength in the emission spectrum of the second fluoride phosphor in the range of 620 nm to 640 nm. An example of a second fluoride phosphor having a composition included in the composition formula represented by formula (IV), an emission peak wavelength in the emission spectrum in the range of 620 nm to 640 nm, and a full width at half maximum of 14 nm or less is a second fluoride phosphor designated as KSAF.

The full width at half maximum in the emission spectrum of the fluoride phosphor is preferably small, and may be, for example, 10 nm or less. The full width at half maximum in the emission spectrum of the fluoride phosphor may be, for example, 1 nm or more. Taking into account the emission efficiency, the maximum excitation wavelength of the fluoride phosphor is preferably in the range of 430 nm to 470 nm, and more preferably in the range of 440 nm to 460 nm.

The average particle size of the fluoride phosphor may be, for example, in the range of 5 μm to 50 μm, and preferably in the range of 10 μm to 30 μm, taking into consideration the emission intensity and improved workability in the manufacturing process of the light emitting device. The light emitting device may contain one type of fluoride phosphor alone, or may contain a combination of two or more types of fluoride phosphors with different compositions.

Nitride phosphor The nitride phosphor having a composition included in the composition formula represented by the formula (V) preferably includes a nitride phosphor having an emission peak wavelength in the range of 600 nm to 630 nm and a full width at half maximum of 80 nm or less in the emission spectrum of the nitride phosphor, for example, a nitride phosphor represented as SCASN. The nitride phosphor may have a full width at half maximum of 40 nm or more in the emission spectrum. The nitride phosphor includes at least one selected from the group consisting of Sr and Ca, but preferably includes both Sr and Ca, and more preferably the Sr content of Sr and Ca is 0.8 mol% or more.

The nitride phosphor having a composition included in the composition formula represented by formula (V) preferably includes a nitride phosphor having an emission peak wavelength in the range of 640 nm to 680 nm in the emission spectrum of the nitride phosphor and a full width at half maximum of 100 nm or less, such as a nitride phosphor represented as CASN. The third nitride phosphor may have a full width at half maximum of 40 nm or more in the emission spectrum.

Taking into consideration the luminous efficiency, the excitation wavelength of the nitride phosphor preferably has a peak intensity in the range of 380 nm to 490 nm, more preferably in the range of 430 nm to 470 nm, and even more preferably in the range of 440 nm to 460 nm.

The average particle size of the nitride phosphor is, for example, in the range of 5 μm to 35 μm, preferably in the range of 15 μm to 25 μm, in consideration of the emission intensity and improvement of workability in the manufacturing process of the light emitting device.
The light emitting device includes two or more nitride phosphors having a composition included in the composition formula represented by formula (V) above and differing in emission peak wavelength range or full width at half maximum.

Other Phosphors The light emitting device may contain other phosphors in addition to the above-mentioned rare earth aluminate phosphors, fluoride phosphors, and nitride phosphors, as necessary. Other phosphors include (Sr,Ba,Ca) ₁₀ ( _PO4 ) ₆ (Br,Cl) ₂ :Eu, (Y,Gd,Tb,Lu) _{3 (} Al,Ga) _{5O12 :} Ce (excluding the first rare earth aluminate phosphor and the _second rare earth aluminate phosphor), _Ca3Sc2Si3O12 : _Ce , _CaSc2O4 :Ce, ₍ La _{,Y)3Si6N11:Ce, (Ca,Sr,Ba)3Si6O9N4 : Eu , ( Ca ,} Sr,Ba) _{3Si6O12N2 :} Eu, (Ba _{, Sr} , _{Ca ) Si2O2N2} :Eu, (Ca,Sr,Ba) _{2Si5N8 :} Eu, (Ca,Sr,Ba)S:Eu, (Ba,Sr,Ca) _{Ga2S4 :} Eu _, etc. When the light emitting device contains other phosphors, the content thereof is appropriately adjusted so as to obtain specific light emitting characteristics.

The phosphor can be a commercially available phosphor. For example, fluoride phosphors can be manufactured by referring to the manufacturing methods described in Japanese Patent Application Nos. 2014-202266 and 2020-212532, which were previously filed by the applicant. Other phosphors can be manufactured, for example, as follows. The elements contained in the composition of the phosphor, such as simple substances, oxides, carbonates, nitrides, chlorides, fluorides, and sulfides, are used as raw materials, and these raw materials are weighed to have a predetermined composition ratio. In addition, additive materials such as flux are appropriately added to the raw materials, and the materials are mixed wet or dry using a mixer. This makes it possible to promote solid-phase reactions and form particles of uniform size. In addition, the mixer may be a ball mill, which is commonly used industrially, or a pulverizer such as a vibration mill, roll mill, or jet mill. The specific surface area can also be increased by pulverizing using a pulverizer. In addition, in order to set the specific surface area of the resulting phosphor particles within a certain range, classification can be performed using wet separators such as settling tanks, hydrocyclones, and centrifuges, and dry classification using cyclones and air separators, which are commonly used in industry. The mixed raw materials are packed into a crucible made of SiC, quartz, alumina, BN, or the like, and fired in an inert atmosphere such as argon or nitrogen, or a reducing atmosphere containing hydrogen. The firing is performed at a specified temperature and time. The fired material is crushed, dispersed, filtered, or the like to obtain the desired phosphor powder. Solid-liquid separation can be performed by a method commonly used in industry, such as filtration, suction filtration, pressure filtration, centrifugation, or decantation. Drying can be performed by a device commonly used in industry, such as a vacuum dryer, a hot air heating dryer, a conical dryer, or a rotary evaporator.

The content of each of the aforementioned phosphors may be selected as described below in (1) to (5) according to the desired correlated color temperature of the light emitted by the light emitting device in order to increase the TLCI values Qa and Q10.

(1) Ratio of total content of fluoride phosphor to total content of rare earth aluminate phosphor When a light emitting device emitting light having a correlated color temperature in the range of 4750 K to 7000 K is used, the ratio of the total content (mass) of fluoride phosphor to the total content (mass) of rare earth aluminate phosphor (total content of fluoride phosphor/total content of rare earth aluminate phosphor) is preferably in the range of 0.35 to 0.70, more preferably in the range of 0.40 to 0.65, and even more preferably in the range of 0.42 to 0.60. Hereinafter, the content of phosphor refers to mass.

When the light emitting device emits light having a correlated color temperature in the range of 2500K or more and less than 4750K, the ratio of the total content of fluoride phosphors to the total content of rare earth aluminate phosphors (total content of fluoride phosphors/total content of rare earth aluminate phosphors) is preferably in the range of 0.60 or more and 1.30 or less, more preferably in the range of 0.65 or more and 1.20 or less, and even more preferably in the range of 0.68 or more and 1.00 or less.

(2) Ratio of the total content of fluoride phosphor to the total content of rare earth aluminate phosphor, fluoride phosphor, and nitride phosphor In the case of a light emitting device that emits light having a correlated color temperature in the range of 4750 K or more and 7000 K or less, the ratio of the total content of fluoride phosphor to the total content of rare earth aluminate phosphor, fluoride phosphor, and nitride phosphor (total content of fluoride phosphor/total content of rare earth aluminate phosphor, fluoride phosphor, and nitride phosphor) is preferably in the range of 0.25 to 0.45, more preferably in the range of 0.26 to 0.40, and even more preferably in the range of 0.28 to 0.34.

When the light emitting device emits light having a correlated color temperature in the range of 2500K or more and less than 4750K, the content ratio of the total content of fluoride phosphors to the total content of rare earth aluminate phosphors, fluoride phosphors, and nitride phosphors (total content of fluoride phosphors/total content of rare earth aluminate phosphors, fluoride phosphors, and nitride phosphors) is preferably in the range of 0.35 to 0.60, more preferably in the range of 0.36 to 0.55, and even more preferably in the range of 0.38 to 0.53.

(3) Ratio of the Total Content of Rare Earth Aluminate Phosphor to the Total Content of Rare Earth Aluminate Phosphor, Fluoride Phosphor, and Nitride Phosphor In the case of a light emitting device that emits light having a correlated color temperature in the range of 4750 K or more and 7000 K or less, the ratio of the total content of rare earth aluminate phosphor to the total content of rare earth aluminate phosphor, fluoride phosphor, and nitride phosphor (total content of rare earth aluminate phosphor/total content of rare earth aluminate phosphor, fluoride phosphor, and nitride phosphor) is preferably in the range of 0.50 to 0.75, more preferably in the range of 0.60 to 0.72, and even more preferably in the range of 0.62 to 0.70.

When the light emitting device emits light having a correlated color temperature in the range of 2500K or more and less than 4750K, the content ratio of the total content of rare earth aluminate phosphors to the total content of rare earth aluminate phosphors, fluoride phosphors, and nitride phosphors (total content of rare earth aluminate phosphors/total content of rare earth aluminate phosphors, fluoride phosphors, and nitride phosphors) is preferably in the range of 0.40 to 0.60, more preferably in the range of 0.45 to 0.59, and even more preferably in the range of 0.50 to 0.58.

(4) Ratio of the total content of fluoride phosphor and nitride phosphor to the total content of rare earth aluminate phosphor, fluoride phosphor, and nitride phosphor In the case of a light emitting device that emits light having a correlated color temperature in the range of 4750 K or more and 7000 K or less, the ratio of the total content of fluoride phosphor and nitride phosphor to the total content of rare earth aluminate phosphor, fluoride phosphor, and nitride phosphor (total content of fluoride phosphor and nitride phosphor/total content of rare earth aluminate phosphor, fluoride phosphor, and nitride phosphor) is preferably in the range of 0.25 to 0.50, more preferably in the range of 0.28 to 0.45, and even more preferably in the range of 0.30 to 0.40.

When the light emitting device emits light having a correlated color temperature in the range of 2500K or more and less than 4750K, the content ratio of the total content of fluoride phosphors and nitride phosphors to the total content of rare earth aluminate phosphors, fluoride phosphors and nitride phosphors (total content of fluoride phosphors and nitride phosphors/total content of rare earth aluminate phosphors, fluoride phosphors and nitride phosphors) is preferably in the range of 0.40 to 0.60, more preferably in the range of 0.41 to 0.55, and even more preferably in the range of 0.42 to 0.50.

(5) Ratio of the total content of fluoride phosphor to the total content of fluoride phosphor and nitride phosphor In the case of a light emitting device that emits light having a correlated color temperature in the range of 3250 K or more and 7000 K or less, the ratio of the total content of fluoride phosphor to the total content of fluoride phosphor and nitride phosphor (total content of fluoride phosphor/total content of fluoride phosphor and nitride phosphor) is preferably in the range of 0.80 or more and 0.99 or less, more preferably in the range of 0.85 or more and 0.98 or less, and even more preferably in the range of 0.90 or more and 0.95 or less.

When the light emitting device emits light having a correlated color temperature in the range of 2500K or more and less than 3250K, the content ratio of the total content of fluoride phosphors to the total content of fluoride phosphors and nitride phosphors (total content of fluoride phosphors/total content of fluoride phosphors and nitride phosphors) is preferably in the range of 0.80 to 0.95, more preferably in the range of 0.82 to 0.93, and even more preferably in the range of 0.85 to 0.92.

Emission spectrum The emission spectrum of the light emitting device is expressed by a spectral distribution with the horizontal axis representing the wavelength and the vertical axis representing the emission intensity. In the emission spectrum of the light emitting device, the emission peak intensity ratio of the emission peak of the fluoride phosphor to the emission peak of the light emitting element is preferably selected according to the correlated color temperature targeted by the light emitting device in order to increase the TLCI values Qa and Q10.
In the case of a light emitting device that emits light having a correlated color temperature in the range of 4750 K or more and 7000 K or less, the emission peak intensity ratio of the emission peak of the fluoride phosphor to the emission peak of the light emitting element in the emission spectrum of the light emitting device is preferably in the range of 1.00 or more and 2.00 or less, more preferably in the range of 1.10 or more and 1.80 or less, and even more preferably in the range of 1.20 or more and 1.70 or less.

When the light emitting device emits light having a correlated color temperature in the range of 3250K or more and less than 4750K, the emission peak intensity ratio of the emission peak of the fluoride phosphor to the emission peak of the light emitting element in the emission spectrum of the light emitting device is preferably in the range of 2.00 or more and 4.50 or less, more preferably in the range of 2.20 or more and 4.00 or less, and even more preferably in the range of 2.50 or more and 3.75 or less.

When the light emitting device emits light having a correlated color temperature in the range of 2850K or more and less than 3250K, the emission peak intensity ratio of the emission peak of the fluoride phosphor to the emission peak of the light emitting element in the emission spectrum of the light emitting device is preferably in the range of 4.00 to 6.00, more preferably in the range of 4.20 to 5.50, and even more preferably in the range of 4.80 to 5.40.

When the light emitting device emits light having a correlated color temperature in the range of 2500K or more and less than 2850K, the emission peak intensity ratio of the emission peak of the fluoride phosphor to the emission peak of the light emitting element in the emission spectrum of the light emitting device is preferably in the range of 5.50 or more and 9.00 or less, more preferably in the range of 6.00 or more and 8.50 or less, and even more preferably in the range of 7.00 or more and 8.40 or less.

Fluorescent Member The light emitting device includes a fluorescent member that contains, for example, a phosphor and a resin and covers the light emitting element. Examples of the resin that constitutes the fluorescent member include thermoplastic resin and thermosetting resin. Specific examples of the thermosetting resin include epoxy resin, silicone resin, and modified silicone resin such as epoxy modified silicone resin.

The fluorescent material may contain other components as necessary in addition to the phosphor and resin. Examples of other components include fillers such as silica, barium titanate, titanium oxide, and aluminum oxide, light stabilizers, and colorants. When the fluorescent material contains other components, the content is not particularly limited and can be appropriately selected depending on the purpose. For example, when the other component contains a filler, the content can be in the range of 0.01% by mass to 60% by mass relative to the resin.

The lighting fixture may include at least one of the above-mentioned light-emitting devices. Furthermore, the lighting fixture may include at least one of the above-mentioned light-emitting devices in combination with a light-emitting device that emits a known white-based mixed color light. In addition to the above-mentioned light-emitting device, the lighting fixture may further include a reflecting member, a protective member, and a device for supplying power to the light-emitting device. The lighting fixture may include a plurality of the above-mentioned light-emitting devices. When the lighting fixture includes a plurality of light-emitting devices, the lighting fixture may include a plurality of the same light-emitting devices, for example, a plurality of light-emitting devices having different correlated color temperatures. In addition, the lighting fixture may include a driving device that can individually drive the plurality of light-emitting devices to adjust the brightness and correlated color temperature according to preference. The lighting fixture may be used in any of a direct-mounted type, an embedded type, and a hanging type.

The following provides a detailed explanation of an embodiment of this disclosure.

Phosphors Prior to the manufacture of the light emitting devices, the following phosphors were prepared as phosphors to be used in the examples and comparative examples.
First rare earth aluminate phosphor: LAG, the emission peak wavelength in the emission spectrum of the first rare earth aluminate phosphor is 521 nm, and the full width at half maximum is 100 nm.
Second rare earth aluminate phosphor: GMAG1, the emission spectrum of the second rare earth aluminate phosphor has an emission peak wavelength of 535 nm and a full width at half maximum of 106 nm;
Second rare earth aluminate phosphor: GYAG2, the emission spectrum of the second rare earth aluminate phosphor has an emission peak wavelength of 541 nm and a full width at half maximum of 107 nm;
Second rare earth aluminate phosphor: YAG, the emission peak wavelength in the emission spectrum of the second rare earth aluminate phosphor is 546 nm, and the full width at half maximum is 110 nm.
First fluoride phosphor: KSF, the emission spectrum of the first fluoride phosphor has an emission peak wavelength of 630 nm and a full width at half maximum of 14 nm,
Nitride phosphor: SCASN, the emission peak wavelength in the emission spectrum of the nitride phosphor is in the range of 600 nm to 630 nm, and the full width at half maximum is 80 nm,
Nitride phosphor: CASN, the emission spectrum of the nitride phosphor has an emission peak wavelength in the range of 640 nm to 680 nm, and a full width at half maximum of 100 nm.

Furthermore, as a phosphor to be used in a comparative light emitting device, a chlorosilicate phosphor having a composition contained in the composition formula represented by the following formula (VI), an emission peak wavelength of 521 nm, and a half width of 63 nm was prepared.
Ca ₈ MgSi ₄ O ₁₆ Cl _l2 :Eu (VI)
The emission peak wavelength and full width at half maximum of each of the above-mentioned phosphors can be adjusted by changing the manufacturing conditions and composition of the phosphor.

The light-emitting elements used were gallium nitride-based semiconductor light-emitting elements with an emission peak wavelength of 450 nm.

Examples 1 to 6
A light emitting device was prepared comprising a light emitting element having an emission peak wavelength of 450 nm, and a fluorescent member containing a phosphor, which was obtained by combining any one of the LAG, the GYAG1, the GYAG2, the YAG, the KSF, the SCASN, and the CASN as shown in Table 1. The symbol "-" in the table indicates that the corresponding phosphor is not included or that the corresponding unit value is not available.
The phosphors and the content of each phosphor were adjusted to the values shown in Table 2 below so that the correlated color temperature was near each of 6500K, 5000K, 4000K, 3500K, 3000K, and 2700K, and the mixed phosphors were added to a silicone resin, mixed and dispersed, and then degassed to obtain a phosphor-containing resin composition. Next, this phosphor-containing resin composition was injected and filled on a light-emitting element, and further heated to harden the resin composition, thereby producing a fluorescent member. A light-emitting device was produced by such a process.

Comparative Examples 1 to 6
A light emitting device was fabricated that included a light emitting element having an emission peak wavelength of 450 nm and a fluorescent member containing a phosphor by combining any one of the GYAG2, SCASN, and chlorosilicate phosphors as shown in Table 2, without including a fluoride phosphor.
Light-emitting devices were produced in the same manner as the light-emitting devices of Examples 1 to 6, except that the contents of each phosphor were adjusted to the values shown in Table 4 below so that the correlated color temperatures were near 6500K, 5000K, 4000K, 3500K, 3000K, and 2700K.

The light emitting devices according to the examples and the light emitting devices according to the comparative examples were measured as follows. The results are shown in Tables 3 and 4.

Emission peak intensity ratio The emission spectrum of each light-emitting device according to the embodiment and each light-emitting device according to the comparative example was measured using a spectrofluorometer. In addition, the emission peak intensity ratio of the emission peak intensity of the emission peak of the fluoride phosphor around 630 nm to the emission peak intensity of the emission peak of the light-emitting element around 450 nm was obtained from the emission spectrum of the light emitted from each light-emitting device. Figures 3 to 8 show the emission spectra of each light-emitting device according to the embodiments 1 to 6 and each light-emitting device according to the comparative examples 1 to 6 and the spectrum of the reference light source at each correlated color temperature. The emission spectra of each light-emitting device and the spectrum of the reference light source shown in Figures 3 to 8 are emission spectra with the maximum emission intensity set to 1.

Correlated color temperature, chromaticity coordinates (x, y), color rendering index (Ra, R15), relative luminous flux (%)
For each of the light emitting devices according to the examples and the comparative examples, the chromaticity coordinates of the emitted color, the correlated color temperature (K), the average color rendering index (Ra), and the special color rendering index (R15) were measured. Specifically, for each of the light emitting devices used in the examples and the comparative examples, the chromaticity coordinates (x, y) in the chromaticity coordinate system of the CIE1931 chromaticity diagram, the correlated color temperature (K), the average color rendering index Ra, the special color rendering index R15, and the luminous flux were measured using a light measurement system combining a spectrophotometer (PMA-12, Hamamatsu Photonics Co., Ltd.) and an integrating sphere. The relative luminous flux of the light emitted by each of the light emitting devices according to the examples was calculated by taking the luminous flux of each of the light emitting devices according to the comparative examples at each correlated color temperature as 100%.

TLCI value Qa, value Q10
For each of the light-emitting devices according to the examples and the light-emitting devices according to the comparative examples, the TLCI values Qa and Q10 were calculated based on the formula described in TLCI-2012 recommended by EBU as described above, using an optical measurement system combining a spectrophotometer (PMA-12, Hamamatsu Photonics K.K.) and an integrating sphere.

As shown in Tables 3 and 4, when comparing the average discoloration index Ra and the TLCI value Qa of each light-emitting device of the Example and Comparative Example, which have almost the same correlated color temperature, the average color rendering index Ra was obtained in the Example and Comparative Example. On the other hand, the TLCI value Qa was higher in the light-emitting device of the Example than in the Comparative Example at each correlated color temperature. Also, for R15, the light-emitting device of the Example was higher than in the Comparative Example at each correlated color temperature. It can be seen that the light-emitting device of the Example has a high TLCI value Qa, and emits light that improves the color reproducibility of the visual object regardless of how the visual object is viewed. In addition, the relative luminous flux of each light-emitting device of the Example and the Comparative Example, which have almost the same correlated color temperature, was obtained with a high luminous flux in each of the light-emitting devices of the Example and the Comparative Example, which have almost the same correlated color temperature, as shown in Tables 3 and 4, with the luminous flux of each comparative example as the reference (100%).
From the above, it is understood that the light emitting device according to the embodiment has a high luminous flux, improves the color reproducibility of the visual object, and has excellent color rendering properties.

Figure 2 shows the TLCI Q10 of the light emitting device of the embodiment and the light emitting device of the comparative example, which emit light with approximately the same correlated color temperature. As shown in Figure 2, at each correlated color temperature, the light emitting device of each embodiment emitted light with a Q10 value of 90 or more, which was higher than that of the light emitting device of the comparative example.

3 to 8 show the emission spectra of the light emitting device according to the embodiment, the emission spectrum of the light emitting device according to the comparative example, and the emission spectrum of the reference light source at each correlated color temperature.
In the emission spectra of the light emitting devices of Examples 1 to 6, the emission intensity of the emission peak in the range of 430 nm to 470 nm did not exceed the emission intensity of the reference light source at each correlated color temperature of around 6500 K, around 5000 K, around 4000 K, around 3500 K, around 3000 K, and around 2700 K, and the emission intensity of blue-purple to blue did not become excessively high, and color balance was maintained. The light emitting devices of Examples 1 to 6 emitted light with a high TLCI value Q10 of 90 or more, and the color balance of each color was maintained and the TLCI value Qa was also high at 90 or more.

In the emission spectra of the light emitting devices of Comparative Examples 1 to 6, at each correlated color temperature of around 6500K, around 5000K, around 4000K, around 3500K, around 3000K, and around 2700K, the emission intensity of the emission peak in the range of 430nm to 470nm is equal to or exceeds the emission intensity of the reference light source, the intensity of the blue-purple to blue emission is high, the color balance is lost, the TLCI value Q10 is low, and depending on the correlated color temperature, the TLCI value Qa is estimated to be lower than 90.

The light-emitting device disclosed herein can be used in lighting fixtures, LED displays, camera flashlights, and other devices with excellent light-emitting properties. Furthermore, it can be used as a lamp that includes this light-emitting device.

10: Light-emitting element, 50: Fluorescent member, 70: Phosphor, 71: Rare earth aluminate phosphor, 72: Fluoride phosphor, 73: Nitride phosphor, 100: Light-emitting device.

Claims (14)

A light emitting device comprising a light emitting element having an emission peak wavelength in the range of 430 nm to 470 nm, and a fluorescent member,
The fluorescent member includes at least one rare earth aluminate phosphor selected from the group consisting of a first rare earth aluminate phosphor having a composition included in a composition formula represented by the following formula (I) and a second rare earth aluminate phosphor having a composition included in a composition formula represented by the following formula (II),
At least one fluoride phosphor selected from the group consisting of a first fluoride phosphor having a composition included in the composition formula represented by the following formula (III) and a second fluoride phosphor having a composition included in the composition formula represented by the following formula (IV),
At least two types of nitride phosphors having a composition included in a composition formula represented by the following formula (V),
A light emitting device that emits light having a value Qa of 90 or more and a value Q10 of 90 or more calculated according to the Television Lighting Consistency Index (TLCI)-2012 recommended by the European Broadcasting Union (EBU).
Lu ₃ Al ₅ O ₁₂ :Ce (I)
Y ₃ (Al _1-a Ga _a ) ₅ O ₁₂ :Ce (II)
(In formula (II), a satisfies 0≦a≦0.5.)
A _c [M ² _1-b Mn ⁴⁺ _b F _d ] (III)
(In formula (III), A includes at least one selected from the group consisting of K ⁺ , Li ⁺ , Na ⁺ , Rb ⁺ , Cs ⁺ and NH ₄ ⁺ ; M ² includes at least one element selected from the group consisting of Group 4 elements and Group 14 elements; b satisfies 0<b<0.2; 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' ] (IV)
(In formula (IV), A' includes at least one selected from the group consisting of K ⁺ , Li ⁺ , Na ⁺ , Rb ⁺ , Cs ⁺ and NH ₄ ⁺ ; M ² ' includes at least one element selected from the group consisting of Group 4 elements, Group 13 elements and Group 14 elements; b' satisfies 0<b'<0.2;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.)
Sr _q Ca _s Al _t Si _u N _v :Eu (V)
(In formula (V), 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.) The ratio of the total content of the fluoride phosphor to the total content of the rare earth aluminate phosphor is
In the case of emitting light having a correlated color temperature in the range of 4750 K or more and 7000 K or less, the ratio is in the range of 0.35 to 0.70,
2. The light emitting device according to claim 1, wherein when emitting light having a correlated color temperature in the range of 2500K or more and less than 4750K, the correlated color temperature is in the range of 0.60 or more and 1.30 or less. The content ratio of the total content of the fluoride phosphor to the total content of the rare earth aluminate phosphor, the fluoride phosphor, and the nitride phosphor is
In the case of emitting light having a correlated color temperature in the range of 4750 K or more and 7000 K or less, the ratio is in the range of 0.25 to 0.45,
2. The light emitting device according to claim 1, wherein when emitting light having a correlated color temperature in the range of 2500K or more and less than 4750K, the correlated color temperature is in the range of 0.35 to 0.60. The content ratio of the total content of the rare earth aluminate phosphor to the total content of the rare earth aluminate phosphor, the fluoride phosphor, and the nitride phosphor is
In the case of emitting light having a correlated color temperature in the range of 4750 K or more and 7000 K or less, the ratio is in the range of 0.50 to 0.75,
2. The light emitting device according to claim 1, wherein when emitting light having a correlated color temperature in the range of 2500K or more and less than 4750K, the correlated color temperature is in the range of 0.40 or more and 0.60 or less. The content ratio of the total content of the fluoride phosphor and the nitride phosphor to the total content of the rare earth aluminate phosphor, the fluoride phosphor, and the nitride phosphor is
In the case of emitting light having a correlated color temperature in the range of 4750 K or more and 7000 K or less, the ratio is in the range of 0.25 to 0.50,
2. The light emitting device according to claim 1, wherein when emitting light having a correlated color temperature in the range of 2500K or more and less than 4750K, the correlated color temperature is in the range of 0.40 or more and 0.60 or less. The content ratio of the total content of the fluoride phosphor to the total content of the fluoride phosphor and the nitride phosphor is
In the case of emitting light having a correlated color temperature in the range of 3250 K or more and 7000 K or less, the coefficient of correlation is in the range of 0.80 to 0.99,
2. The light emitting device according to claim 1, wherein when light is emitted having a correlated color temperature in the range of 2500K to 3250K, the correlated color temperature is in the range of 0.80 to 0.95. In the emission spectrum of the light emitting device, the emission peak intensity ratio of the emission peak of the fluoride phosphor to the emission peak of the light emitting element is
In the case of emitting light having a correlated color temperature in the range of 4750 K or more and 7000 K or less, the range is 1.00 or more and 2.00 or less.
In the case of emitting light having a correlated color temperature in the range of 3250 K or more and less than 4750 K, the range is 2.00 or more and 4.00 or less,
In the case of emitting light having a correlated color temperature in the range of 2850 K or more and less than 3250 K, the correlated color temperature is in the range of 4.00 or more and 6.00 or less,
The light emitting device according to claim 1 , wherein when emitting light having a correlated color temperature in the range of 2500K or more and less than 2850K, the correlated color temperature is in the range of 5.50 or more and 9.00 or less. The light-emitting device according to any one of claims 1 to 7, wherein the light-emitting element has an emission peak wavelength in the range of 440 nm to 460 nm. The light emitting device according to any one of claims 1 to 8, wherein the first rare earth aluminate phosphor includes a first rare earth aluminate phosphor having an emission peak wavelength in an emission spectrum in the range of 500 nm to 540 nm and a full width at half maximum in the range of 95 nm to 105 nm. 9. The light emitting device according to claim 1, wherein the second rare earth aluminate phosphor includes a second rare earth aluminate phosphor having an emission peak wavelength in an emission spectrum in the range of 520 nm to 550 nm and a full width at half maximum in the range of 95 nm to 115 nm. 9. The light emitting device according to claim 1, wherein the second rare earth aluminate phosphor includes a second rare earth aluminate phosphor having an emission peak wavelength in an emission spectrum in the range of 535 nm to 555 nm and a full width at half maximum in the range of 100 nm to 120 nm. The light emitting device according to any one of claims 1 to 11, wherein the nitride phosphor includes a nitride phosphor having an emission peak wavelength in an emission spectrum in the range of 600 nm to 630 nm and a full width at half maximum of 80 nm or less. The light emitting device according to any one of claims 1 to 12, wherein the nitride phosphor includes a nitride phosphor having an emission spectrum with an emission peak wavelength in the range of 640 nm to 680 nm and a full width at half maximum of 100 nm or less. A lamp equipped with a light-emitting device according to any one of claims 1 to 13.

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