JP6460040B2 - Light emitting device - Google Patents

Description

  The present disclosure relates to a light emitting device.

  As a light emitting device that emits white light using a light emitting diode (hereinafter also referred to as “LED”), for example, there is a light emitting device that combines a blue light emitting LED and a yellow light emitting phosphor. This light emitting device emits white light by mixing the blue light of the LED with yellow light from the phosphor excited by the light.

  In such a light emitting device, although the radiation intensity in the visible light region is strong and the light emission efficiency is high, the radiation intensity in the blue-green region and the red region may not be sufficiently obtained. Therefore, there is room for further improvement in the average color rendering evaluation index, which is an index of the color appearance (color rendering) of the irradiated object.

  By the way, the color rendering property evaluation procedure of the light source is JIS Z8726, and the color difference ΔEi (i is from 1) when the test colors (R1 to R15) having predetermined reflectance characteristics are measured with the test light source and the reference light source, respectively. It is stipulated that the numerical value of what will be an integer of 15 is calculated. Here, the upper limit of the color rendering index Ri (i is an integer from 1 to 15) is 100. That is, the smaller the color difference between the test light source and the reference light source corresponding to the color temperature, the closer the color rendering evaluation value approaches 100 and the higher the value.

  In order to enhance the color rendering of the light source, a light emitting device using a blue light emitting LED and a chlorosilicate phosphor and a Y or Tb garnet phosphor as two types of phosphors emitting green to yellow is proposed. (For example, refer to Patent Document 1). In order to further improve color rendering properties, a light emitting device using a phosphor that emits red light in addition to a phosphor that emits light from green to yellow has been proposed (see, for example, Patent Document 2).

Special Table 2003-535477 JP 2008-034188 A

  Light emitting devices for lighting use have a wide range of needs, from general lighting used in homes to special lighting that requires high color rendering, such as medical lighting and museums. It is not easy to control the emission spectrum so as to match the reference light source at the color temperature required for such various uses and to obtain a light source having a very small color difference between each Ri. In particular, when trying to obtain a white mixed color light by combining various types of phosphors, yellow to green and red, each fluorescence is different from the case of using one kind of yellow phosphor. Adjustment of each color component in the body's emission spectrum is complicated. Furthermore, when an emission spectrum having a very small difference in the specific Ri with respect to the reference light source is to be obtained, there is a high possibility that a difference occurs in any other difference in the expression.

  Accordingly, an object of one embodiment of the present invention is to solve the above-described problems and provide a light-emitting device that can achieve excellent color rendering.

  In order to solve the above problems, a first embodiment according to the present invention includes a light emitting element having an emission peak wavelength in a range of 430 nm to 470 nm and a fluorescent member, and a light having a correlated color temperature of 3500 K to 4500 K. The fluorescent member is activated by Eu, and includes a first phosphor containing an alkaline earth aluminate, a second phosphor activated by Mn and containing a fluorogermanate, and activated by Ce. A total phosphor of the first to fourth phosphors, comprising a third phosphor containing a rare earth aluminate and a fourth phosphor containing silicon nitride activated by Eu and having a composition of Sr, Ca, Al. The light-emitting device whose content ratio of said 1st fluorescent substance with respect to a body weight is 3.0 mass% or more and 55.0 mass% or less is included.

  In order to solve the above-mentioned problem, a second embodiment according to the present invention includes a light emitting element having a light emission peak wavelength in a range of 430 nm to 470 nm and a fluorescent member, and has a correlated color temperature of 4500 K or more and 5500 K or less. The fluorescent member is activated by Eu, and includes a first phosphor containing an alkaline earth aluminate, a second phosphor activated by Mn and containing a fluorogermanate, and activated by Ce. A total phosphor of the first to fourth phosphors, comprising a third phosphor containing a rare earth aluminate and a fourth phosphor containing silicon nitride activated by Eu and having a composition of Sr, Ca, Al. The light-emitting device whose content ratio of the 1st fluorescent substance with respect to a body weight is 3.5 to 65.0 mass% is included.

  In order to solve the above problems, a third embodiment according to the present invention includes a light emitting element having an emission peak wavelength in a range of 430 nm to 470 nm, and a fluorescent member, and has a correlated color temperature of 5500 K to 7000 K. The fluorescent member is activated by Eu, and includes a first phosphor containing an alkaline earth aluminate, a second phosphor activated by Mn and containing a fluorogermanate, and activated by Ce. A total phosphor of the first to fourth phosphors, comprising a third phosphor containing a rare earth aluminate and a fourth phosphor containing silicon nitride activated by Eu and having a composition of Sr, Ca, Al. The light-emitting device whose content ratio of the 1st fluorescent substance with respect to body mass is 7.5 to 55.0 mass% is included.

  According to an embodiment of the present disclosure, it is possible to provide a light emitting device that can achieve high color rendering properties.

FIG. 1 is a schematic cross-sectional view showing an example of a light emitting device according to this embodiment. FIG. 2 is a diagram illustrating emission spectra of the light emitting devices according to Examples 1 and 2 and Comparative Examples 1 and 2. FIG. 3 is a diagram illustrating emission spectra of the light emitting devices according to Examples 3 and 4 and Comparative Examples 1 and 3. FIG. 4 is a diagram illustrating the emission spectra of the light emitting devices according to Examples 5 to 7 and Comparative Example 4. FIG. 5 is a diagram illustrating emission spectra of the light emitting devices according to Examples 8 and 9 and Comparative Example 4. FIG. 6 is a diagram illustrating the emission spectra of the light emitting devices according to Example 10 and Comparative Examples 4 and 5. FIG. 7 is a diagram illustrating emission spectra of the light emitting devices according to Examples 11 to 13 and Comparative Example 6. FIG. 8 is a diagram illustrating the emission spectra of the light emitting devices according to Examples 14 and 15 and Comparative Examples 6 and 7.

  Hereinafter, modes for carrying out the present invention will be described. However, the embodiment described below exemplifies a light emitting device for embodying the technical idea of the present invention, and the present invention is not limited to the following light emitting device. In this specification, the relationship between color names and chromaticity coordinates, the relationship between the wavelength range of light and the color name of monochromatic light, and the like are in accordance with JIS Z8110. Further, the content of each component in the composition means the total amount of the plurality of substances present in the composition unless there is a specific notice when there are a plurality of substances corresponding to each component in the composition. .

  FIG. 1 is a schematic cross-sectional view of a light emitting device 100 according to an embodiment of the present invention. The light emitting device 100 includes a light emitting element 10 having a light emission peak wavelength in a range of 430 nm to 470 nm and a fluorescent member 50. The fluorescent member 50 includes a first phosphor 71 activated with Eu and containing an alkaline earth aluminate, a second phosphor 72 activated with Mn and containing a fluorogermanate, and a rare earth aluminate activated with Ce. A third phosphor 73 containing a salt and a fourth phosphor 74 containing silicon nitride activated by Eu and having Sr, Ca, Al in its composition are included. Hereinafter, the first phosphor 71, the second phosphor 72, the third phosphor 73, and the fourth phosphor 74 are collectively referred to as a phosphor 70.

  By using the light emitting element 10 having the emission peak wavelength in the range of 430 nm or more and 470 nm or less and the first phosphor 71 to the fourth phosphor 74 in combination, light emission of the light emitting device in a relatively wide range from the short wave side to the long wave side The spectrum can be brought close to the spectrum of the reference light source. This makes it possible to achieve excellent color rendering properties.

  Regarding color rendering properties The CIE (International Commission on Illumination) published guidelines for color rendering properties that fluorescent lamps should have in 1986, and according to these guidelines, the preferred average color rendering index according to the location used ( (Hereinafter referred to as Ra) is 60 to less than 80 in factories that perform general work, and 80 to less than 90 in houses, hotels, restaurants, stores, offices, schools, hospitals, factories that perform precision work, etc., and has high color rendering. There are over 90 in places such as museums where clinical tests are required.

  Ra of the light emitting device 100 is, for example, 80 or more, preferably 90 or more, and more preferably 95 or more. The upper limit of Ra is 100. Also, the special color rendering index is expressed by R9 to R15. R9 is red, R10 is yellow, R11 is green, R12 is blue, R13 is Western skin color, R14 is leaf color, R15 is It is said to be the color of Japanese skin. In particular, in the lighting device used in an environment where meat or the like is used, the number of evaluations of R9 is often noticed, and in the environment related to apparel and photography, the appearance fidelity is often required. It is said that the higher the special color rendering index is, the more preferable. R9 to R15 of the light emitting device of the present embodiment is, for example, 40 or more, preferably 50 or more, and more preferably 60 or more. Each of R9 to R15 has an upper limit of 100.

  The light emitted from the light emitting device 100 is a mixed color light of the light emitted from the light emitting element 10 and the fluorescence emitted from the first phosphor 71, the second phosphor 72, the third phosphor 73, and the fourth phosphor 74. , The chromaticity coordinates defined in CIE1931 can be light included in the range of x = 0.00 to 0.50 and y = 0.00 to 0.50, and x = 0.25 to 0.00. 40 and y = 0.25 to 0.40.

  The correlated color temperature of the light emitted from the light emitting device 100 can be, for example, 3000K or higher, and can be 3500K or higher. The correlated color temperature can be set to 7500K or lower, and can be set to 7000K or lower.

  Hereinafter, the light emitting device 100 will be described in more detail. The light emitting device 100 emits light on the short wavelength side of visible light (for example, a range of 380 nm to 485 nm), and the light emitting device 10 of a gallium nitride compound semiconductor having an emission peak wavelength in a range of 430 nm to 470 nm, And a molded body 40 on which the light emitting element 10 is placed. The molded body 40 is formed by integrally molding the first lead 20 and the second lead 30 and a resin portion 42 containing a thermoplastic resin or a thermosetting resin. The molded body 40 has a recess having a bottom surface and side surfaces, 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 20 and the second lead 30 through wires 60, respectively. The light emitting element 10 is covered with a fluorescent member 50.

[Fluorescent member 50]
The fluorescent member 50 includes a phosphor 70 that converts the wavelength of light from the light emitting element 10 and a resin. The resin preferably contains a thermosetting resin such as an epoxy resin, a silicone resin, an epoxy-modified silicone resin, or a modified silicone resin. The phosphor 70 includes a first phosphor 71, a second phosphor 72, a third phosphor 73, and a fourth phosphor 74. The fluorescent member 50 contains the phosphor 70, but other materials can be added as appropriate. For example, by including a light diffusing material, the directivity from the light emitting element can be relaxed and the viewing angle can be increased.

  The fluorescent member 50 functions not only as a wavelength conversion member including the phosphor 70 of light emitted from the light emitting element 10 but also 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. Thus, by arranging the phosphor 70 close to the light emitting element 10, the wavelength of light from the light emitting element 10 can be efficiently converted, and a light emitting device having excellent light emission efficiency can be obtained. The arrangement of the fluorescent member 50 including the phosphor 70 and the light emitting element 10 is not limited to the form in which they are arranged close to each other, and the fluorescent member is considered in consideration of the influence of heat on the phosphor 70. 50, the light emitting element 10 and the phosphor 70 may be spaced apart. Further, the color unevenness is further suppressed by mixing the phosphor 70 in the entire fluorescent member 50 at a substantially uniform ratio.

[Light emitting element 10]
The emission peak wavelength of the light-emitting element 10 is in the range of 430 nm to 470 nm, preferably in the range of 440 nm to 460 nm, and more preferably in the range of 445 nm to 455 nm. By using a light emitting element having an emission peak wavelength in this range as an excitation light source, light emitted from the light emitting element to the outside can be used effectively, so that loss of light emitted from the light emitting device is reduced. And a light emitting device with high luminous efficiency can be obtained.

  The light emitting element 10 is preferably a semiconductor light emitting element such as an LED. By using a semiconductor light emitting element as a light source, it is possible to obtain a stable light emitting device with high efficiency, high output linearity with respect to input, and strong against mechanical shock.

As a semiconductor light emitting element, for example, a blue color using a nitride semiconductor (In _X Al _Y Ga _1- XYN, where X and Y satisfy 0 ≦ X, 0 ≦ Y, and X + Y ≦ 1). A semiconductor light emitting element that emits green light or the like can be used. The half width of the emission spectrum of the light emitting element 10 is not particularly limited. The half width can be set to 30 nm or less, for example.

[Phosphor 70]
The light emitting device 100 includes the fluorescent member 50 including the first phosphor 71 to the fourth phosphor 74 as described above. About each of the 1st fluorescent substance 71 thru | or the 4th fluorescent substance 74, it is not limited to one type of composition, You may use combining several types of fluorescent substance from which a composition differs. By appropriately selecting the composition ratio of the first phosphor 71, the second phosphor 72, the third phosphor 73, and the fourth phosphor 74, the characteristics such as the light emission efficiency and color rendering properties of the light emitting device are set in a desired range. Can do.

(First phosphor 71)
The first phosphor 71 is a phosphor activated with Eu and containing an alkaline earth aluminate. The first phosphor 71 is preferably a green light-emitting phosphor having a composition represented by the following formula (1) and activated by europium. Thereby, each light emission characteristic of the 1st fluorescent substance 71 demonstrated below can be obtained comparatively easily.
Sr ₄ Al ₁₄ O ₂₅ : Eu (1)

  The maximum excitation wavelength of the first phosphor 71 is preferably 270 nm or more and 470 nm or less, and more preferably 370 nm or more and 460 nm or less. This is for efficient excitation within the range of the emission peak wavelength of the light emitting element 10. The emission peak wavelength of the first phosphor 71 is preferably in the range of 440 nm to 550 nm, and more preferably in the range of 460 nm to 530 nm. By setting it as such a range, duplication with the emission spectrum of the light emitting element 10 and the emission spectrum of the 3rd fluorescent substance 73 mentioned later can be decreased, and the emission spectrum of the 1st fluorescent substance 71 can be closely approached to a reference light source. Therefore, the color rendering properties of the light emitting device can be improved. The half width in the emission spectrum of the first phosphor 71 is, for example, not less than 58 nm and not more than 78 nm, and preferably not less than 63 nm and not more than 73 nm. By setting the half-value width in such a range, the color purity can be improved, the emission spectrum in the green region can be brought close to the reference light source, and the color rendering properties of the light emitting device can be improved.

(Content ratio of the first phosphor 71 with respect to the total phosphor amount)
In the case of a light emitting device that emits light having a correlated color temperature of 3500 K or more and 4500 K or less, the content ratio of the first phosphor 71 to the total phosphor amount is 3% by mass or more, preferably 6% by mass or more, More preferably, it is at least 30% by mass, and even more preferably at least 30% by mass. The content ratio of the first phosphor 71 with respect to the total phosphor amount is 55% by mass or less, preferably 50% by mass or less, more preferably 45% by mass or less, and 40% by mass or less. More preferably it is. When the content ratio is within the above range, the emission spectrum of a light emitting device that emits light having a correlated color temperature of 3500K or more and 4500K or less can be brought closer to the reference light source, so that color rendering can be further improved.

  In the case of a light emitting device that emits light having a correlated color temperature of 4500K or more and 5500K or less, the content ratio of the first phosphor 71 with respect to the total phosphor amount is 3.5% by mass or more and 6.5% by mass or more. Is preferably 15.0% by mass or more, more preferably 30.0% by mass or more. The content ratio of the first phosphor 71 with respect to the total phosphor amount is 65.0% by mass or less, preferably 55.0% by mass or less, and more preferably 50.0% by mass or less. More preferably, it is 45.0 mass% or less. When the content ratio is within the above range, the emission spectrum of a light emitting device that emits light having a correlated color temperature of 4500K or more and 5500K or less can be brought closer to the reference light source, so that color rendering can be further improved.

  In the case of a light emitting device that emits light having a correlated color temperature of 5500K or more and 7000K or less, the content ratio of the first phosphor 71 to the total phosphor amount is 7.5% by mass or more, and preferably 10% by mass or more. More preferably, the content is 20% by mass or more, and further preferably 30% by mass or more. The content ratio of the first phosphor 71 with respect to the total phosphor amount is 55% by mass or less, preferably 50% by mass or less, more preferably 45% by mass or less, and 40% by mass or less. More preferably it is. When the content ratio is within the above range, the emission spectrum of a light emitting device that emits light having a correlated color temperature of 5500 K or more and 7000 K or less can be brought closer to the reference light source, so that color rendering can be further improved.

(Second phosphor 72)
The second phosphor 72 is a phosphor activated with Mn and containing a fluorogermanate. The second phosphor 72 has a composition represented by the following formula (2), and is preferably a deep red light-emitting phosphor activated by manganese. The emission peak wavelength of this phosphor is relatively longer than other phosphors emitting red light and is 650 nm or more. Therefore, the emission spectrum on the long wavelength side can be effectively brought close to the reference light source, so that the color rendering properties of the light emitting device can be increased.
(Xs) MgO. (S / 2) Sc ₂ O ₃ .yMgF ₂ .uCaF _2. (1-t) GeO _2. (T / 2) M ^t ₂ O ₃ : zMn ⁴⁺ (2)

However, in formula (2), x, y, z, s, t, and u are 2.0 ≦ x ≦ 4.0, 0 <y <1.5, 0 <z <0.05, 0 ≦ s. <0.5, 0 <t <0.5, 0 ≦ u <1.5 is satisfied, and y + u <1.5 is preferably satisfied. Further, M ^t in the general formula (2) is at least one selected from the group consisting of Al, Ga and In.

In the formula (2), 0.05 ≦ s ≦ 0.3 and 0.05 ≦ t <0.3 are preferably satisfied, whereby the luminance can be further improved. Furthermore equation (2) _{is, 3.4MgO · 0.1Sc 2 O 3 ·} 0.5MgF 2 · 0.885GeO 2 · 0.1Ga 2 O 3: is preferably represented by the 0.015Mn ^4+. Thereby, the 2nd fluorescent substance 72 can be efficiently excited with the light of the wavelength range containing the light emission peak wavelength of the said light emitting element.

  The half width in the emission spectrum of the second phosphor 72 is not particularly limited, and is, for example, 45 nm or less, and preferably 40 nm or less. By setting the half-value width in such a range, the color purity can be improved and the emission spectrum in the red region can be brought close to the reference light source, so that the color rendering properties of the light emitting device can be improved. The emission spectrum of the second phosphor 72 has an average emission intensity in the range of 600 nm or more and 620 nm or less, preferably 20% or less, when the maximum emission intensity is 100%, preferably 10% or less. More preferred. If it is less than or equal to the above upper limit value, the emission spectrum of the second phosphor 72 is less likely to overlap with the emission spectrum of the fourth phosphor 74, which will be described later. Can be improved.

(Content ratio of the second phosphor 72 to the total phosphor amount)
In the case of a light emitting device that emits light having a correlated color temperature of 3500 K or more and 4500 K or less, the content ratio of the second phosphor 72 to the total phosphor amount is 25% by mass or more, and preferably 28% by mass or more. More preferably, it is at least mass%. In addition, the content ratio of the second phosphor 72 with respect to the total phosphor amount is 37% by mass or less, preferably 36% by mass or less, and more preferably 33% by mass or less. When the content ratio is within the above range, the emission spectrum of a light emitting device that emits light having a correlated color temperature of 3500K or more and 4500K or less can be brought closer to the reference light source, so that color rendering can be further improved.

  In the case of a light emitting device that emits light having a correlated color temperature of 4500K or more and 5500K or less, the content ratio of the second phosphor 72 to the total phosphor amount is 22% by mass or more, preferably 24% by mass or more, More preferably, it is at least mass%. The content ratio of the second phosphor 72 with respect to the total phosphor amount is 32% by mass or less, preferably 31% by mass or less, and more preferably 29% by mass or less. When the content ratio is within the above range, the emission spectrum of a light emitting device that emits light having a correlated color temperature of 4500K or more and 5500K or less can be brought closer to the reference light source, so that color rendering can be further improved.

  In the case of a light emitting device that emits light having a correlated color temperature of 5500 K or more and 7000 K or less, the content ratio of the second phosphor 72 to the total phosphor amount is 16% by mass or more, and preferably 17% by mass or more. More preferably, it is at least mass%. The content ratio of the second phosphor 72 with respect to the total phosphor amount is 24% by mass or less, preferably 20% by mass or less, and more preferably 19% by mass or less. When the content ratio is within the above range, the emission spectrum of a light emitting device that emits light having a correlated color temperature of 5500 K or more and 7000 K or less can be brought closer to the reference light source, so that color rendering can be further improved.

(Third phosphor 73)
The third phosphor 73 is a phosphor activated with Ce and containing a rare earth aluminate. The third phosphor 73 has a composition represented by the following formula (3), and is preferably a yellow light-emitting phosphor activated by cerium. Thereby, each light emission characteristic of the 3rd fluorescent substance 73 demonstrated below can be obtained comparatively easily.
Y ₃ Al ₅ O ₁₂ : Ce (3)

  The maximum excitation wavelength of the third phosphor 73 is preferably 220 nm or more and 490 nm or less, and more preferably 430 nm or more and 470 nm or less. This is for efficient excitation within the range of the emission peak wavelength of the light emitting element 10. The emission peak wavelength of the third phosphor 73 is preferably 480 nm or more and 630 nm or less, and more preferably 500 nm or more and 560 nm or less. By setting it as such a range, duplication with the emission spectrum of the 1st fluorescent substance 71 and the emission spectrum of the 4th fluorescent substance 74 mentioned later is decreased, and the emission spectrum of the 3rd fluorescent substance 73 is brought close to a reference light source. And the color rendering properties of the light emitting device can be improved. The full width at half maximum in the emission spectrum of the third phosphor 73 is, for example, not less than 95 nm and not more than 115 nm, and preferably not less than 100 nm and not more than 110 nm. By setting such a half-value width range, the color purity can be improved and the emission spectrum in the yellow region can be brought close to the reference light source, so that the color rendering properties of the light-emitting device can be improved.

(Content ratio of the third phosphor relative to the total amount of phosphor)
In the case of a light emitting device that emits light having a correlated color temperature of 3500 K or more and 4500 K or less, the content ratio of the third phosphor 73 with respect to the total phosphor amount is 18% by mass or more, and preferably 20% by mass or more. More preferably, it is at least mass%. The content ratio of the third phosphor 73 with respect to the total phosphor amount is 59% by mass or less, preferably 50% by mass or less, and more preferably 35% by mass or less. When the content ratio is within the above range, the emission spectrum of a light emitting device that emits light having a correlated color temperature of 3500K or more and 4500K or less can be brought close to the reference light source, and color rendering can be improved.

  In the case of a light emitting device that emits light having a correlated color temperature of 4500K or more and 5500K or less, the content ratio of the third phosphor 73 with respect to the total phosphor amount is 20% by mass or more, preferably 25% by mass or more, More preferably, it is at least mass%. The content ratio of the third phosphor 73 with respect to the total phosphor amount is 60% by mass or less, preferably 50% by mass or less, and more preferably 35% by mass or less. When the content ratio is within the above range, the emission spectrum of a light emitting device that emits light having a correlated color temperature of 4500K or more and 5500K or less can be brought close to a reference light source, and color rendering can be improved.

  In the case of a light emitting device that emits light having a correlated color temperature of 5500 K or more and 7000 K or less, the content ratio of the third phosphor 73 with respect to the total phosphor amount is 25% by mass or more, and preferably 30% by mass or more. More preferably, it is at least mass%. The content ratio of the third phosphor 73 with respect to the total phosphor amount is 70% by mass or less, preferably 60% by mass or less, and more preferably 50% by mass or less. When the content ratio is within the above range, the emission spectrum of a light emitting device that emits light having a correlated color temperature of 5500 K or more and 7000 K or less can be brought close to the reference light source, and color rendering can be improved.

(Fourth phosphor 74)
The fourth phosphor 74 is a phosphor containing silicon nitride activated by Eu and having Sr, Ca, Al in its composition. The fourth phosphor 74 is preferably a red light-emitting phosphor having a composition represented by the following formula (4) and activated by europium. Thereby, each light emission characteristic of the 4th fluorescent substance 74 demonstrated below can be obtained comparatively easily.
(Sr, Ca) AlSiN ₃ : Eu (4)

  The fourth phosphor 74 includes at least one selected from the group consisting of Sr and Ca, but preferably includes both Sr and Ca, and the Sr content ratio of Sr and Ca is 0.8 mol%. More preferably. This is because the emission peak wavelength of the fourth phosphor 74 can be in the range described below.

  The emission peak wavelength of the fourth phosphor 74 is preferably 620 nm or more and 650 nm or less, and more preferably 630 nm or more and 645 nm or less. If it is equal to or more than the lower limit, the emission spectrum can be brought close to the reference light source without the light emission component between the emission peak wavelength of the second phosphor 72 and the emission peak wavelength of the fourth phosphor 74 being insufficient. If the upper limit is not exceeded, the emission spectrum of the fourth phosphor 74 is less likely to overlap the emission spectrum of the second phosphor 72, so that the effect of the emission spectrum of the second phosphor 72 is obtained and color rendering is achieved. Can be improved. The half width in the emission spectrum of the fourth phosphor 74 is, for example, not less than 80 nm and not more than 100 nm, and preferably not less than 85 nm and not more than 95 nm. By setting the range of such a half-value width, the emission spectrum of the fourth phosphor 74 is less likely to overlap with the emission spectrum of the second phosphor 72, so that the effect of the emission spectrum of the second phosphor 72 is obtained. Color rendering can be improved.

(Content ratio of the fourth phosphor 74 with respect to the total phosphor amount)
In the case of a light emitting device that emits light having a correlated color temperature of 3500K or more and 4500K or less, the content ratio of the fourth phosphor 74 to the total phosphor amount is 2.9 mass% or more and 3.3 mass% or less. When the content ratio is within the above range, the emission spectrum of the light emitting device can be made closer to the reference light source, so that color rendering can be further improved.

  In the case of a light emitting device that emits light having a correlated color temperature of 4500K or more and 5500K or less, the content ratio of the fourth phosphor 74 to the total phosphor amount is 2.8 mass% or more and 3.0 mass% or less. When the content ratio is within the above range, the emission spectrum of the light emitting device can be made closer to the reference light source, so that color rendering can be further improved.

  In the case of a light emitting device that emits light having a correlated color temperature of 5500K or more and 7000K or less, the content ratio of the fourth phosphor 74 to the total phosphor amount is 2.4% by mass or more and 2.9% by mass or less. When the content ratio is within the above range, the emission spectrum of the light emitting device can be made closer to the reference light source, so that color rendering can be further improved.

(Content ratio of the first phosphor 71 to the third phosphor 73)
In the case of a light emitting device that emits light having a correlated color temperature of 3500 K or more and 4500 K or less, the content ratio of the first phosphor 71 to the third phosphor 73 is preferably 0.05 or more and 3.00 or less, and 0.50. It is more preferably 2.00 or more and 2.00 or less, and further preferably 1.00 or more and 1.50 or less. When the content ratio is within the above range, the light emission spectrum of the light emitting device can be made closer to the reference light source, so that the color rendering can be further improved.

  In the case of a light emitting device that emits light having a correlated color temperature of 4500K or more and 5500K or less, the content ratio of the first phosphor 71 to the third phosphor 73 is preferably 0.06 or more and 4.70 or less, and 0.30. It is more preferably 2.70 or less and even more preferably 1.00 or more and 1.50 or less. When the content ratio is within the above range, the light emission spectrum of the light emitting device can be made closer to the reference light source, so that the color rendering can be further improved.

  In the case of a light emitting device that emits light having a correlated color temperature of 5500 K or more and 7000 K or less, the content ratio of the first phosphor 71 to the third phosphor 73 is preferably 0.10 or more and 2.10 or less, and 0.20. It is more preferably 1.5 or more and 1.5 or less, and further preferably 0.40 or more and 1.00 or less. When the content ratio is within the above range, the light emission spectrum of the light emitting device can be made closer to the reference light source, so that the color rendering can be further improved.

(Emission peak intensity ratio of the first phosphor 71 with respect to the light emitting element 10)
The emission peak intensity of the first phosphor 71 relative to the emission peak intensity of the light-emitting element 10 in the emission spectrum in which the fluorescent member 50 is obtained from a light emitting device including the first phosphor 71 and the horizontal axis indicates the wavelength and the vertical axis indicates the emission intensity. The ratio is not particularly limited, and may be appropriately selected according to the target correlated color temperature and desired light emission characteristics.

  In the case of a light emitting device that emits light having a correlated color temperature of 3500 K or more and 4500 K or less, the emission peak intensity ratio of the first phosphor 71 to the light emitting element 10 is 0.40 or more when the emission intensity of the light emitting element 10 is 1. It is preferably 0.75 or less, more preferably 0.45 or more and 0.70 or less, and further preferably 0.50 or more and 0.65 or less. When the emission peak intensity ratio is within the above range, the emission spectrum of the light emitting device can be made closer to the reference light source, so that the color rendering can be further improved.

  In the case of a light emitting device that emits light having a correlated color temperature of 4500K or more and 5500K or less, the emission peak intensity ratio of the first phosphor 71 to the light emitting element 10 is 0.34 or more when the emission intensity of the light emitting element 10 is 1. It is preferably 0.60 or less, more preferably 0.35 or more and 0.55 or less, and further preferably 0.40 or more and 0.50 or less. When the emission peak intensity ratio is within the above range, the emission spectrum of the light emitting device can be made closer to the reference light source, so that the color rendering can be further improved.

  In the case of a light emitting device that emits light having a correlated color temperature of 5500 K or more and 7000 K or less, the emission peak intensity ratio of the first phosphor 71 to the light emitting element 10 is 0.25 or more when the emission intensity of the light emitting element 10 is 1. It is preferably 0.42 or less, more preferably 0.30 or more and 0.40 or less, and further preferably 0.33 or more and 0.38 or less. When the emission peak intensity ratio is within the above range, the emission spectrum of the light emitting device can be made closer to the reference light source, so that the color rendering can be further improved.

  The light emitting device may include other phosphors other than the first phosphor 71 to the fourth phosphor 74 as necessary. When the light-emitting device contains other phosphors, the content is not particularly limited, but is appropriately adjusted so that the light-emitting characteristics of the present invention can be obtained.

(Phosphor)
The following phosphors were prepared as phosphors of Examples and Comparative Examples.
As the first phosphor 71, a green-emitting phosphor (hereinafter, also referred to as “SAE”) having a composition represented by Sr ₄ Al ₁₄ O ₂₅ : Eu and having an emission peak wavelength near 494 nm was prepared. .
As the second phosphor _{72, 3.4MgO · 0.1Sc 2 O 3} · 0.5MgF 2 · 0.885GeO 2 · 0.1Ga 2 O 3: having a composition represented by 0.015Mn ^4+, emission A deep red light emitting phosphor (hereinafter also referred to as “MGF”) having a peak wavelength near 658 nm was prepared.
As the third phosphor 73, a rare earth aluminum garnet phosphor (hereinafter also referred to as “YAG”) having a composition represented by Y ₃ Al ₅ O ₁₂ : Ce and having an emission peak wavelength near 544 nm was prepared. .
As the fourth phosphor 74, a red-emitting nitride phosphor having a composition represented by (Sr, Ca) AlSiN ₃ : Eu and having an emission peak wavelength around 635 nm (hereinafter also referred to as “SCASN”). Prepared.

Example 1
A light emitting device was manufactured by combining a blue light emitting LED having an emission peak wavelength of 450 nm with SAE, MGF, YAG, and SCASN.

  A phosphor blended so that the SAE content ratio to the total phosphor amount is 6.9% and the correlated color temperature is around 5000K is added to the silicone resin, mixed and dispersed, and then defoamed to obtain fluorescence. A body-containing resin composition was obtained. This phosphor-containing resin composition was injected and filled on the light emitting element, and further heated to cure the resin composition. A light emitting device was manufactured through such a process.

(Examples 2 to 4)
A light emitting device was produced in the same manner as in Example 1 except that the amount of the phosphor was changed so that the content ratio of each phosphor became the value shown in Table 1 below.

With respect to the light-emitting devices obtained in Examples 1 to 4, the chromaticity coordinates of the emission color, the correlated color temperature (Tcp; K), the average color rendering index (Ra), and the special color rendering index (R9 to R15) were measured. Hereinafter, the average color rendering index and the special color rendering index are also simply referred to as “color rendering index”.
The emission spectrum of the light emitting device was measured using a spectrofluorometer F-4500 manufactured by Hitachi High-Technologies. In addition, it measured similarly about the other Example and comparative example which are described below.
The results other than the color rendering index are shown in Table 1 below, and the results of the color rendering index are shown in Table 2 below. Rt in Table 2 represents the total sum of the color rendering evaluation numbers from R9 to R15.

  As shown in Tables 1 and 2, in Examples 1 to 4, by adjusting the amount of SAE, Rt is larger than Comparative Examples 1 to 3 described later, and a light emitting device having high color rendering properties We were able to.

  From Table 1, in all of Examples 1 to 4, the correlated color temperature was in the range of 4500K to 5500K. In Examples 2, 3, and 4, the content ratio of SAE with respect to the total amount of phosphor is 7.0% by mass or more and 55.0% by mass or less, and the content ratio of MGF with respect to the total amount of phosphor is 22.0% by mass or more. It is contained in the range of 31.0 mass% or less. Further, the content ratio of YAG with respect to the total phosphor amount is included in the range of 20.0 mass% or more and 55.0 mass% or less. Moreover, the content ratio of SCASN with respect to the total amount of phosphor is included in the range of 2.8% by mass to 3.0% by mass. The content ratio of the first phosphor 71 (SAE) to the third phosphor 73 (YAG) is included in the range of 0.30 to 2.70. By setting these content ratios and content ratios, the emission spectrum of the light-emitting device can be approximated to a reference light source. In these Examples 2, 3 and 4, the average color rendering index Ra is 90 or more, and the special color rendering index R9, R10, R11, R12, R13, R14 and R15 are all 60 or more, and Rt The numerical value shows 570 or more, and it turns out that color rendering property is especially excellent.

  2 shows the emission spectra of the light emitting devices according to Comparative Examples 1 and 2, and Examples 1 and 2, and FIG. 3 shows the emission spectra of the light emitting devices according to Comparative Examples 1 and 3 and Examples 3 and 4, respectively, at 530 nm. It is the figure which normalized and compared on the basis of the emitted light intensity. The emission spectra in FIGS. 2 and 3 show the relative emission intensity with respect to the wavelength. The spectrum of a reference light source of 5000K is also shown in each figure. In Examples 2, 3 and 4, as shown in Table 1, the intensity ratio of the emission peak of the first phosphor 71 to the light emitting element 10 in the emission spectrum is 0.35 or more and 0.60 or less. In these Examples 2, 3 and 4, as shown in Table 2, the average color rendering index Ra is 90 or more, and the special color rendering index R9, R10, R11, R12, R13, R14 and R15 are Is 60 or more, and the Rt value is 570 or more, indicating that the color rendering properties are particularly excellent.

(Comparative Example 1)
A light-emitting device was fabricated in the same manner as in Example 1 except that MGF, YAG, and SCASN were used in combination without using SAE as the phosphor.

(Comparative Examples 2 and 3)
A light emitting device was manufactured in the same manner as in Example 1 except that the amount of the phosphor was changed so that the content ratio of each phosphor became the value shown in Table 3 below.

  Regarding the light emitting devices obtained in Comparative Examples 1 to 3, the results other than the color rendering index are shown in Table 3 below, and the results of the color rendering index are shown in Table 4 below.

  As shown in Table 4, in Comparative Examples 1 to 3, Rt was smaller than that of the Example, and the color rendering property of the light emitting device was low.

(Examples 5 to 10)
The light emitting device was manufactured in the same manner as in Example 1 except that the amount of the phosphor was changed so that the content ratio of each phosphor became the value shown in Table 5 below, and the correlated color temperature was adjusted to around 4000K. Produced.

  Regarding the light emitting devices obtained in Examples 5 to 10, the results other than the color rendering index are shown in Table 5 below, and the results of the color rendering index are shown in Table 6 below.

  As shown in Tables 5 and 6, in Examples 5 to 10, by adjusting the amount of SAE, Rt is larger than Comparative Examples 4 and 5 described later, and a light emitting device having high color rendering properties We were able to.

  From Table 5, Examples 5 to 10 all had a correlated color temperature in the range of 3500K to 4500K. In Examples 5 to 10, the SAE content ratio to the total phosphor amount is 3.0% by mass or more and 55.0% by mass or less, and the MGF content ratio to the total phosphor amount is 25.0% by mass to 37%. It is contained in the range of 0 mass% or less. Further, the content ratio of YAG with respect to the total phosphor amount is included in the range of 18.0% by mass or more and 59.0% by mass or less. Moreover, the content ratio of SCASN with respect to the total phosphor amount is included in the range of 2.9 mass% to 3.3 mass%. The content ratio of the first phosphor 71 (SAE) to the third phosphor 73 (YAG) is included in the range of 0.05 to 3.00. In these Examples 5 to 10, the emission spectrum of the light emitting device can be approximated to the reference light source by setting the content ratio and the content ratio thereof. In these Examples 5 to 10, the special color rendering index R9, R10, R11, R12, R13, R14 and R15 are all 60 or more, and the numerical value of Rt is larger than 555. It turns out that it is excellent in property.

  Further, in Examples 8 and 9, the content ratio of SAE with respect to the total phosphor amount is 16.5 mass% or more and 50.0 mass% or less, and the content ratio of MGF with respect to the total phosphor amount is 28.0 mass% or more. 33.0% by mass or less, the YAG content ratio with respect to the total phosphor amount is 20.0% by mass or more and 35.0% by mass or less, and the SCASN content ratio with respect to the total phosphor amount is 3.0% by mass or more. It is contained in the range of 3.2 mass% or less. The content ratio of the first phosphor 71 (SAE) to the third phosphor 73 (YAG) is included in the range of 0.40 to 2.60. In Examples 8 and 9, the average color rendering index Ra is 90 or more, the special color rendering index R9, R10, R11, R12, R13, R14 and R15 are all 60 or more, and the numerical value of Rt is It shows 600 or more, and it can be seen that the color rendering property is particularly excellent.

  4 shows the emission spectra of the light emitting devices according to Comparative Example 4 and Examples 5 to 7, FIG. 5 shows the emission spectra of the light emitting devices according to Comparative Example 4 and Examples 8 and 9, and FIG. 6 shows the comparative example. 4 and 5 are diagrams in which the emission spectra of the light emitting devices according to Example 10 are normalized and compared based on the emission intensity of 530 nm. The emission spectra in FIGS. 4 to 6 show the relative emission intensity with respect to the wavelength. The spectrum of a 4000 K reference light source is also shown in each figure. In Examples 5 to 10, as shown in Table 5, the intensity ratio of the emission peak of the first phosphor 71 to the light emitting element 10 in the emission spectrum is 0.40 or more and 0.75 or less. In these Examples 5 to 10, as shown in Table 6, the numerical value of Rt indicates 555 or more, and it can be seen that the color rendering properties are excellent. In Example 8, as shown in Table 5, the intensity ratio of the emission peak of the first phosphor 71 to the light emitting element 10 in the emission spectrum is 0.60 or more and 0.65 or less. In Example 8, as shown in Table 6, the numerical value of Rt indicates 660 or more, and it can be seen that the color rendering property is particularly excellent.

(Comparative Example 4)
A light emitting device was fabricated in the same manner as in Example 1 except that MGF, YAG, and SCASN were used in combination without using SAE as the phosphor, and that the correlated color temperature was adjusted to around 4000K.

(Comparative Example 5)
A light emitting device was fabricated in the same manner as in Example 1 except that the amount of the phosphor was changed so that the content ratio of each phosphor became the value shown in Table 7 below.

  Regarding the light emitting devices obtained in Comparative Examples 4 and 5, the results other than the color rendering index are shown in Table 7 below, and the results of the color rendering index are shown in Table 8 below.

  As shown in Table 8, in Comparative Examples 4 and 5, Rt was smaller than that of the Example, and the color rendering property of the light emitting device was low.

(Examples 11 to 15)
The light emitting device was manufactured in the same manner as in Example 1 except that the amount of the phosphor was changed so that the content ratio of each phosphor became the value shown in Table 9 below, and the correlated color temperature was adjusted to around 6500K. Produced.

  Regarding the light emitting devices obtained in Examples 11 to 15, the results other than the color rendering index are shown in Table 9 below, and the results of the color rendering index are shown in Table 10 below.

  As shown in Tables 9 and 10, in Examples 11 to 15, by adjusting the amount of SAE, Rt is larger than Comparative Examples 6 and 7 described later, and a light emitting device having high color rendering properties. We were able to.

  As shown in Table 9, in Examples 11 to 15, the correlated color temperature was in the range of 5500K to 7000K. In Examples 11 to 15, as shown in Table 9, the SAE content ratio to the total phosphor amount is 7.5% by mass or more and 55.0% by mass or less, and the MGF content ratio to the total phosphor amount is It is contained in the range of 16.0 mass% or more and 24.0 mass% or less. Further, the content ratio of YAG with respect to the total phosphor amount is included in the range of 25.0 mass% or more and 70.0 mass% or less. Moreover, the content ratio of SCASN with respect to the total phosphor amount is included in the range of 2.4 mass% or more and 2.9 mass% or less. The content ratio of the first phosphor 71 (SAE) to the third phosphor 73 (YAG) is included in the range of 0.10 to 2.10. By setting these content ratios and content ratios, the emission spectrum of the light-emitting device can be approximated to a reference light source. In these Examples 11 to 15, as shown in Table 10, the average color rendering index Ra is 90 or more, and the special color rendering index R9, R10, R11, R12, R13, R14 and R15 are all 60. Thus, the numerical value of Rt indicates 580 or more, and it can be seen that the color rendering property is excellent.

  Further, in Examples 13 and 14, as shown in Table 9, the content ratio of SAE with respect to the total phosphor amount is 15.0% by mass or more and 40.0% by mass or less, and the content of MGF with respect to the total phosphor amount The ratio is 18.0% by mass or more and 20.0% by mass or less, the YAG content ratio with respect to the total phosphor amount is 35.0% by mass or more and 60.0% by mass or less, and the SCASN content with respect to the total phosphor amount The ratio is included in the range of 2.6% by mass to 2.7% by mass. The content ratio of the first phosphor 71 (SAE) to the third phosphor 73 (YAG) is included in the range of 0.30 to 1.00. In these Examples 13 and 14, as shown in Table 10, the numerical value of Rt shows 610 or more, and it can be seen that the color rendering properties are particularly excellent.

  FIG. 7 shows the emission spectra of the light emitting devices according to Comparative Example 6 and Examples 11 to 13, and FIG. 8 shows the emission spectra of the light emitting devices according to Comparative Examples 6 and 7, and Examples 14 and 15, respectively. It is the figure which normalized and compared on the basis of intensity | strength. The emission spectra of FIGS. 7 and 8 show the relative emission intensity with respect to the wavelength. The spectrum of a 6500K reference light source is also shown in each figure. In Examples 11 to 15, as shown in Table 9, the intensity ratio of the emission peak of the first phosphor 71 to the light emitting element 10 in the emission spectrum is 0.25 or more and 0.42 or less. In these Examples 11 to 15, as shown in Table 10, the Rt value is 580 or more, and it can be seen that the color rendering properties are excellent. Further, in Examples 13 and 14, as shown in Table 9, the intensity ratio of the emission peak of the first phosphor 71 to the light emitting element 10 in the emission spectrum is 0.30 or more and 0.38 or less. In these Examples 13 and 14, as shown in Table 10, the numerical value of Rt shows 610 or more, and it can be seen that the color rendering properties are particularly excellent.

(Comparative Example 6)
A light-emitting device was fabricated in the same manner as in Example 1 except that MGF, YAG, and SCASN were used in combination without using SAE as the phosphor and that the correlated color temperature was adjusted to around 6000K.

(Comparative Example 7)
A light emitting device was fabricated in the same manner as in Example 1 except that the amount of the phosphor was changed so that the content ratio of each phosphor became the value shown in Table 11 below.

  Regarding the light emitting devices obtained in Comparative Examples 6 and 7, the results other than the color rendering index are shown in Table 11 below, and the results of the color rendering index are shown in Table 12 below.

  As shown in Table 12, in Comparative Examples 6 and 7, Rt was smaller than that of the Example, and the color rendering property of the light emitting device was low.

  The light emitting device of the present disclosure can be used for a lighting fixture, an LED display, a camera flashlight, and the like that have excellent light emission characteristics using a blue light emitting diode or an ultraviolet light emitting diode as an excitation light source. In particular, it can be suitably used for lighting equipment and light sources that require high color rendering properties.

  10: light emitting element, 50: fluorescent member, 70: phosphor, 71: first phosphor, 72: second phosphor, 73: third phosphor, 74: fourth phosphor, 100: light emitting device.

Claims (17)

A light emitting device that includes a light emitting element having an emission peak wavelength in a range of 430 nm to 470 nm and a fluorescent member, and emits light having a correlated color temperature of 3500K to 4500K,
The fluorescent member has a first phosphor having a composition represented by the following formula (1), a second phosphor having a composition represented by the following formula (2), and a composition represented by the following formula (3). Including a third phosphor and a fourth phosphor having a composition represented by the following formula (4):
The content ratio of the first phosphor to the total phosphor amount of the first phosphor to the fourth phosphor is 16.5 mass% or more and 50.0 mass% or less,
The content ratio of the second phosphor relative to the total phosphor amount is 28.0 mass% or more and 33.0 mass% or less,
The content ratio of the third phosphor relative to the total phosphor amount is 20.0 mass% or more and 35.0 mass% or less,
The light-emitting device whose content ratio of the said 4th fluorescent substance with respect to the said total fluorescent substance amount is 3.0 mass% or more and 3.2 mass% or less.
Sr ₄ Al ₁₄ O ₂₅ : Eu (1)
(Xs) MgO. (S / 2) Sc ₂ O ₃ .yMgF ₂ .uCaF _2. (1-t) GeO _2. (T / 2) M ^t ₂ O ₃ : zMn ⁴⁺ (2)
(In the formula (2), M ^t is at least one selected from the group consisting of Al, Ga and In, and x, y, z, s, t and u are 2 ≦ x ≦ 4, 0 <, respectively. (y <1.5, 0 <z <0.05, 0 ≦ s <0.5, 0 <t <0.5, and 0 ≦ u <1.5 are satisfied.)
Y ₃ Al ₅ O ₁₂ : Ce (3)
(Sr, Ca) AlSiN ₃ : Eu (4) The light emitting device according to claim 1, wherein a content ratio of the first phosphor to the third phosphor is 0.40 or more and 2.60 or less .   The light emitting device according to claim 1 or 2, wherein an intensity ratio of an emission peak of the first phosphor to an emission peak of the light emitting element is 0.40 or more and 0.75 or less. The average color rendering index Ra is 90 or more,
Special color rendering index R9, R10, R11, R12, R13, R14 and R15 are all 60 or more,
The light emitting device according to any one of claims 1 to 3, wherein a total sum of the special color rendering index numbers R9, R10, R11, R12, R13, R14, and R15 is 600 or more. A light-emitting device that includes a light-emitting element having an emission peak wavelength in a range of 430 nm to 470 nm and a fluorescent member, and emits light having a correlated color temperature of 4500K to 5500K,
The fluorescent member has a first phosphor having a composition represented by the following formula (1), a second phosphor having a composition represented by the following formula (2), and a composition represented by the following formula (3). Including a third phosphor and a fourth phosphor having a composition represented by the following formula (4):
The content ratio of the first phosphor to the total phosphor amount of the first phosphor to the fourth phosphor is 7.0 mass% or more and 55.0 mass% or less,
The content ratio of the second phosphor with respect to the total phosphor amount is 22.0 mass% or more and 31.0 mass% or less,
The content ratio of the third phosphor relative to the total phosphor amount is 20.0 mass% or more and 55.0 mass% or less,
The light-emitting device whose content ratio of the said 4th fluorescent substance with respect to the said total fluorescent substance amount is 2.8 mass% or more and 3.0 mass% or less.
Sr ₄ Al ₁₄ O ₂₅ : Eu (1)
(Xs) MgO. (S / 2) Sc ₂ O ₃ .yMgF ₂ .uCaF _2. (1-t) GeO _2. (T / 2) M ^t ₂ O ₃ : zMn ⁴⁺ (2)
(In the formula (2), M ^t is at least one selected from the group consisting of Al, Ga and In, and x, y, z, s, t and u are 2 ≦ x ≦ 4, 0 <, respectively. (y <1.5, 0 <z <0.05, 0 ≦ s <0.5, 0 <t <0.5, and 0 ≦ u <1.5 are satisfied.)
Y ₃ Al ₅ O ₁₂ : Ce (3)
(Sr, Ca) AlSiN ₃ : Eu (4) The light emitting device according to claim 5, wherein a content ratio of the first phosphor to the third phosphor is 0.30 or more and 2.70 or less .   The light emitting device according to claim 5 or 6, wherein an intensity ratio of an emission peak of the first phosphor to an emission peak of the light emitting element is 0.34 or more and 0.60 or less. The average color rendering index Ra is 90 or more,
Special color rendering index R9, R10, R11, R12, R13, R14 and R15 are all 60 or more,
The light emitting device according to any one of claims 5 to 7, wherein a sum of the special color rendering index numbers R9, R10, R11, R12, R13, R14, and R15 is 570 or more. A light-emitting device that includes a light-emitting element having an emission peak wavelength in a range of 430 nm to 470 nm and a fluorescent member, and emits light having a correlated color temperature of 5500K to 7000K,
The fluorescent member has a first phosphor having a composition represented by the following formula (1), a second phosphor having a composition represented by the following formula (2), and a composition represented by the following formula (3). Including a third phosphor and a fourth phosphor having a composition represented by the following formula (4):
The content ratio of the first phosphor to the total phosphor amount of the first phosphor to the fourth phosphor is 15.0 mass% or more and 40.0 mass% or less,
The content ratio of the second phosphor relative to the total phosphor amount is 18.0% by mass or more and 20.0% by mass or less,
The content ratio of the third phosphor relative to the total phosphor amount is 35.0 mass% or more and 60.0 mass% or less,
The light-emitting device whose content ratio of the said 4th fluorescent substance with respect to the said total fluorescent substance amount is 2.6 mass% or more and 2.7 mass% or less.
Sr ₄ Al ₁₄ O ₂₅ : Eu (1)
(Xs) MgO. (S / 2) Sc ₂ O ₃ .yMgF ₂ .uCaF _2. (1-t) GeO _2. (T / 2) M ^t ₂ O ₃ : zMn ⁴⁺ (2)
(In the formula (2), M ^t is at least one selected from the group consisting of Al, Ga and In, and x, y, z, s, t and u are 2 ≦ x ≦ 4, 0 <, respectively. (y <1.5, 0 <z <0.05, 0 ≦ s <0.5, 0 <t <0.5, and 0 ≦ u <1.5 are satisfied.)
Y ₃ Al ₅ O ₁₂ : Ce (3)
(Sr, Ca) AlSiN ₃ : Eu (4) The light emitting device according to claim 9, wherein a content ratio of the first phosphor to the third phosphor is 0.30 or more and 1.00 or less .   The light emitting device according to claim 9 or 10, wherein an intensity ratio of an emission peak of the first phosphor to an emission peak of the light emitting element is 0.25 or more and 0.42 or less. The average color rendering index Ra is 90 or more,
Special color rendering index R9, R10, R11, R12, R13, R14 and R15 are all 60 or more,
The light emitting device according to any one of claims 9 to 11, wherein a sum of the special color rendering index numbers R9, R10, R11, R12, R13, R14, and R15 is 610 or more.   The light emitting device according to any one of claims 1 to 12, wherein a half width in an emission spectrum of the first phosphor is 58 nm or more and 78 nm or less.   The light emitting device according to any one of claims 1 to 13, wherein a half width in an emission spectrum of the second phosphor is 45 nm or less.   The light emitting device according to any one of claims 1 to 14, wherein a half width in an emission spectrum of the third phosphor is 95 nm or more and 115 nm or less.   The light emitting device according to any one of claims 1 to 15, wherein a half width in an emission spectrum of the fourth phosphor is 80 nm or more and 100 nm or less.   The light emitting device according to any one of claims 1 to 16, wherein the light emitting element has a light emission peak in a wavelength range of 440 nm to 460 nm.

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