Light-emitting device and lighting fixture equipped with same

Abstract

To provide a light emitting device having a high light emitting spectrum having an excellent light emitting spectrum for visual work and a lighting device provided with the light emitting device.SOLUTION: A light emitting device includes a light emitting element 10 having an emission peak wavelength in the range of 400 nm or more and 490 nm or less, and a phosphor material including a first phosphor 71 having an emission peak in the range of 510 nm or more and less than 580 nm, a second phosphor 72 having an emission peak wavelength in the range of 580 nm or more and 680 nm or less and having a half width of 15 nm or more and 100 nm or less in the emission spectrum, and a third phosphor 73 having an emission peak wavelength in the range of 600 nm or more and 650 nm or less and having a half width of 14 nm or less in the emission spectrum, and when the correlated color temperature is, for example, 2000 K or more and less than 2800 K, a melanopic ratio (MR) value is 0.47 or more and 0.73 or less.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present invention relates to a light-emitting device and a lamp including the same. [Background technology]

[0002] As a light-emitting device using a light-emitting element such as a light-emitting diode (hereinafter referred to as "LED"), a white light-emitting device using a blue-emitting light-emitting element and a yellow-emitting phosphor is well known. Such light-emitting devices are used in a wide range of fields, including general lighting, automotive lighting, displays, and LCD backlights. In recent years, as LED lighting has become more widespread, interest has been growing in the effects of LED lighting on the human body. For example, Patent Document 1 describes that LED lighting can affect human circadian rhythms (bioryhythms).

[0003] The word "circadian" is a combination of the Latin words "circa," meaning "about," and "dies," meaning "day," and refers to "circadian rhythm." Humans wake up and feel sleepy on a daily cycle because their internal clocks function rather than being influenced by external environmental factors such as changes in brightness or darkness. The human sleep and body temperature cycle is approximately 25 hours, slightly longer than a day. However, in normal life, external environmental changes stimulate the body clocks, adjusting their phase. Living organisms use light as a synchronizing factor. Humans with a 25-hour cycle synchronize by advancing their phase with morning light, while mice with a 23-hour cycle synchronize by delaying their phase with light before sunset. Light-triggered control of the body clock is therefore crucial for shaping circadian rhythms.

[0004] In 2002, a new photoreceptor, distinct from rods and cones, was discovered in the mammalian retina. It was named the intrinsically photosensitive retinal ganglion cell (ipRGC). ipRGCs contain the photopigment melanopsin and have been shown to be involved in non-visual functions such as circadian rhythm entrainment and the pupillary reflex. ipRGCs transmit light signals via direct administration to the suprachiasmatic nucleus (SNU). The SNU is a very small region in the hypothalamus of the brain that acts as the biological clock that orchestrates mammalian circadian rhythms. Approximately 20,000 neurons in the SNU generate circadian rhythms for various physiological functions, including sleep, wakefulness, blood pressure, body temperature, and hormone secretion. Therefore, controlling the intrinsic light response of ipRGCs is crucial for circadian rhythm formation.

[0005] Melanopsin, a photoreceptor protein found in ipRGCs, is expressed in approximately 1-2% of retinal ganglion cells. The majority of other retinal ganglion cells are not photosensitive. The absorption characteristics of these photoreceptors vary depending on the cell, with melanopsin having a peak wavelength around 480-490 nm. Cone opsins have peak wavelengths of around 440 nm for S cones, 535 nm for M cones, and 565 nm for L cones, while rhodopsin found in rods has a peak wavelength of around 507 nm.

[0006] Melanopsin is also thought to be closely involved in the secretion or suppression of melatonin, a sleep-promoting hormone. For example, it is believed that increasing the amount of stimulation to ipRGCs suppresses melatonin secretion. Melatonin secretion peaks at night, and its secretion makes people sleepy and promotes sleep. Light that suppresses melatonin secretion is thought to be preferable for lighting in places where office work such as using a computer or holding meetings is performed.

[0007] In recent years, the concept of human-centric lighting (HCL) has become widespread, and circadian-conscious lighting has become a mandatory requirement for the WELL certification, a new building certification focused on worker health. Equivalent melanopic illuminance is used as a quantitative unit of brightness that affects circadian rhythms, and a vertical equivalent melanopic illuminance of 250 lux or more is required, covering at least 75% of the office space and for at least four hours per day. Calculating equivalent melanopic illuminance requires the melanopic ratio (MR) calculated from the spectral distribution of the light source. Equivalent melanopic illuminance can be calculated using the following formula (1), and the melanopic ratio can be calculated using the following formula (2).

[0008]

number

[0009]

number

[0010] The circadian action curve used to calculate the melanopic ratio uses the ipRGC sensitivity curve (circadian action curve, absorbance). The visual action curve uses the human photopic luminosity curve. Using the ipRGC sensitivity curve and the human photopic luminosity curve, it can be determined that the higher the melanopic ratio, the stronger the spectral distribution that stimulates the circadian rhythm.

[0011] The melanopic ratio is influenced by components around 480nm to 490nm, so it is thought that it tends to increase as color rendering improves, but the trade-off for high color rendering is a decrease in luminous efficacy. Therefore, in order to provide lighting that takes circadian rhythms into consideration, it is necessary to control the melanopic ratio according to the circadian rhythm while also achieving luminous efficacy. [Prior art documents] [Patent documents]

[0012] [Patent Document 1] International Publication No. 2012 / 144087 Summary of the Invention [Problem to be solved by the invention]

[0013] Therefore, one aspect of the present invention aims to provide a light-emitting device and a lighting fixture equipped with the same, which has a spectrum that exhibits a high melanopic ratio, suppresses a decrease in luminous efficiency, and has high color rendering properties that are suitable for visual tasks. [Means for solving the problem]

[0014] The present invention includes the following aspects. The first aspect is a light-emitting element having an emission peak wavelength in the range of 400 nm or more and 490 nm or less, and a light-emitting element having an emission peak wavelength in the range of 510 nm or more and less than 580 nm. Wavelength a second phosphor having an emission peak wavelength in the range of 600 nm to 650 nm and a half-width of the emission spectrum of 15 nm to 100 nm; and a third phosphor having an emission peak wavelength in the range of 600 nm to 650 nm and a half-width of the emission spectrum of 14 nm or less, and the light emitting device has a melanopic ratio (MR) value that satisfies the following ranges for the correlated color temperature ranges (1) to (5) shown below.

[0015] (1) When the correlated color temperature is 2000K or more and less than 2800K, the MR value is 0.47 or more and 0.73 or less; (2) When the correlated color temperature is 2800K or more and less than 3500K, the MR value is 0.53 or more and 0.81 or less; (3) When the correlated color temperature is 3500K or more and less than 4500K, the MR value is 0.68 or more and 1.00 or less; (4) When the correlated color temperature is 4500K or more and less than 5700K, the MR value is 0.84 or more and 1.18 or less; (5) When the correlated color temperature is 5700K or more and less than 7200K, the MR value is 1.00 or more and 1.40 or less.

[0016] A second aspect is a lamp including the light emitting device. [Effects of the Invention]

[0017] According to one aspect of the present invention, it is possible to provide a light-emitting device and a lighting fixture equipped with the same that have a spectrum that exhibits a high melanopic ratio, suppress a decrease in luminous efficiency, and have high color rendering properties that are suitable for visual tasks. [Brief explanation of the drawings]

[0018] [Figure 1] FIG. 1 is a schematic cross-sectional view showing an example of a light emitting device. [Figure 2] FIG. 2 is a diagram showing the reflectance spectra of the second phosphor and the third phosphor. [Figure 3] FIG. 3 is a diagram showing the emission spectra and luminous efficiency spectra of the second phosphor and the third phosphor. [Figure 4] FIG. 4 is a diagram showing the emission spectrum of the light emitting device according to Example 1 and the emission spectra of the light emitting devices according to Comparative Examples 1 and 2. In FIG. [Figure 5] FIG. 5 is a diagram showing the emission spectrum of the light emitting device according to Example 2 and the emission spectra of the light emitting devices according to Comparative Examples 1 and 2. In FIG. [Figure 6] FIG. 6 is a diagram showing the emission spectrum of the light emitting device according to Example 3 and the emission spectra of the light emitting devices according to Comparative Examples 1 and 2. In FIG. [Figure 7]FIG. 7 is a diagram showing the emission spectrum of the light emitting device according to Example 4 and the emission spectra of the light emitting devices according to Comparative Examples 1 and 2. In FIG. [Figure 8] FIG. 8 is a diagram showing the emission spectrum of the light emitting device according to Example 5 and the emission spectra of the light emitting devices according to Comparative Examples 3 and 4. In FIG. [Figure 9] FIG. 9 is a diagram showing the emission spectrum of the light emitting device according to Example 6 and the emission spectra of the light emitting devices according to Comparative Examples 3 and 4. In FIG. [Figure 10] FIG. 10 is a diagram showing the emission spectrum of the light emitting device according to Example 7 and the emission spectra of the light emitting devices according to Comparative Examples 3 and 4. In FIG. [Figure 11] FIG. 11 is a diagram showing the emission spectrum of the light emitting device according to Example 8 and the emission spectra of the light emitting devices according to Comparative Examples 3 and 4. In FIG. [Figure 12] FIG. 12 is a diagram showing the emission spectrum of the light emitting device according to Example 9 and the emission spectra of the light emitting devices according to Comparative Examples 3 and 4. In FIG. [Figure 13] FIG. 13 is a diagram showing the emission spectrum of the light emitting device according to Example 10 and the emission spectra of the light emitting devices according to Comparative Examples 5 and 6. In FIG. [Figure 14] FIG. 14 is a diagram showing the emission spectrum of the light emitting device according to Example 11 and the emission spectra of the light emitting devices according to Comparative Examples 5 and 6. In FIG. [Figure 15] FIG. 15 is a diagram showing the emission spectrum of the light emitting device according to Example 12 and the emission spectra of the light emitting devices according to Comparative Examples 5 and 6. In FIG. [Figure 16] FIG. 16 is a diagram showing the emission spectrum of the light emitting device according to Example 13 and the emission spectra of the light emitting devices according to Comparative Examples 5 and 6. In FIG. [Figure 17] FIG. 17 is a diagram showing the emission spectrum of the light emitting device according to Example 14 and the emission spectra of the light emitting devices according to Comparative Examples 7 and 8. In FIG. [Figure 18] FIG. 18 is a diagram showing the emission spectrum of the light emitting device according to Example 15 and the emission spectra of the light emitting devices according to Comparative Examples 7 and 8. In FIG. [Figure 19]FIG. 19 is a diagram showing the emission spectrum of the light emitting device according to Example 16 and the emission spectra of the light emitting devices according to Comparative Examples 7 and 8. In FIG. [Figure 20] FIG. 20 is a diagram showing the emission spectrum of the light emitting device according to Example 17 and the emission spectra of the light emitting devices according to Comparative Examples 7 and 8. In FIG. [Figure 21] FIG. 21 is a diagram showing the emission spectrum of the light emitting device according to Example 18 and the emission spectra of the light emitting devices according to Comparative Examples 7 and 8. In FIG. [Figure 22] FIG. 22 is a diagram showing the emission spectrum of the light emitting device according to Example 19 and the emission spectra of the light emitting devices according to Comparative Examples 7 and 8. In FIG. [Figure 23] FIG. 23 is a diagram showing the emission spectrum of the light emitting device according to Example 20 and the emission spectra of the light emitting devices according to Comparative Examples 7 and 8. In FIG. [Figure 24] FIG. 24 is a diagram showing the emission spectrum of the light emitting device according to Example 21 and the emission spectra of the light emitting devices according to Comparative Examples 7 and 8. In FIG. [Figure 25] FIG. 25 is a diagram showing the emission spectrum of the light emitting device according to Example 22 and the emission spectra of the light emitting devices according to Comparative Examples 9 and 10. In FIG. [Figure 26] FIG. 26 is a diagram showing the emission spectrum of the light emitting device according to Example 23 and the emission spectra of the light emitting devices according to Comparative Examples 9 and 10. In FIG. [Figure 27] FIG. 27 is a diagram showing the emission spectrum of the light emitting device according to Example 24 and the emission spectra of the light emitting devices according to Comparative Examples 9 and 10. In FIG. [Figure 28] FIG. 28 is a diagram showing the emission spectrum of the light emitting device according to Example 25 and the emission spectra of the light emitting devices according to Comparative Examples 9 and 10. In FIG. DETAILED DESCRIPTION OF THE INVENTION

[0019] The light-emitting device and the lamp including the same according to the present invention will be described below based on one embodiment. However, the embodiment shown below is an example of a light-emitting device and a lamp including the same to embody the technical idea of ​​the present invention, and the present invention is not limited to the light-emitting device and the lamp including the same described below. The relationship between color names and chromaticity coordinates, and the relationship between light wavelength ranges and monochromatic light color names, etc., conforms to JIS Z8110. Furthermore, when the composition contains multiple substances corresponding to each component, the content of each component in the composition means the total amount of those multiple substances present in the composition, unless otherwise specified.

[0020] [Light-emitting device] The light emitting device includes a light emitting element having an emission peak wavelength in the range of 400 nm to 490 nm, and a light emitting element having an emission peak wavelength in the range of 510 nm to less than 580 nm. Wavelength the fluorescent component includes a first phosphor having a peak emission wavelength in the range of 580 nm to 680 nm and a half-width in the emission spectrum of 15 nm to 100 nm, and a second phosphor having a peak emission wavelength in the range of 600 nm to 650 nm and a half-width in the emission spectrum of 14 nm or less, and the melanopic ratio (MR) value satisfies the following ranges for the correlated color temperature ranges shown in any of (1) to (5) below. Note that the melanopic ratio in this specification was calculated using action curves normalized by setting the sensitivity at the peak wavelength of each of the ipRGC sensitivity curve and the luminosity curve in human photopic vision to 1.

[0021] (1) When the correlated color temperature is 2000 K or more and less than 2800 K, the MR value is, for example, 0.47 or more, preferably 0.48 or more, more preferably 0.50 or more, and even more preferably 0.51 or more, and is 0.73 or less, preferably 0.68 or less, and more preferably 0.63 or less. (2) When the correlated color temperature is 2800K or more and less than 3500K, the MR value is, for example, 0.53 or more, preferably 0.54 or more, more preferably 0.56 or more, and 0.81 or less, preferably 0.76 or less, more preferably 0.71 or less. (3) When the correlated color temperature is 3500K or more and less than 4500K, the MR value is, for example, 0.68 or more, preferably 0.69 or more, more preferably 0.70 or more, and 1.00 or less, preferably 0.95 or less, more preferably 0.90 or less. (4) When the correlated color temperature is 4500K or more and less than 5700K, the MR value is, for example, 0.84 or more, preferably 0.85 or more, more preferably 0.89 or more, and even more preferably 0.93 or more, and is 1.18 or less, preferably 1.13 or less, and more preferably 1.08 or less. (5) When the correlated color temperature is 5700K or more and less than 7200K, the MR value is, for example, 1.00 or more, preferably 1.01 or more, more preferably 1.04 or more, and 1.40 or less, preferably 1.35 or less, more preferably 1.30 or less.

[0022] An example of a light emitting device will be described below with reference to the drawings.

[0023] As shown in FIG. 1, the light emitting device 100 includes a light emitting element 10 having an emission peak wavelength in the range of 400 nm to 490 nm, and a fluorescent member 50 including a phosphor 70 that emits light upon being excited by light from the light emitting element.

[0024] The light-emitting device 100 includes, for example, a molded body 40, a light-emitting element 10, and a fluorescent member 50. The molded body 40 is formed by integrally molding a first lead 20, a second lead 30, and a resin portion 42 containing a thermoplastic resin or a thermosetting resin. The molded body 40 forms 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, which 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 includes, for example, a phosphor 70 that converts the wavelength of light from the light-emitting element 10 and a sealing material. The phosphor 70 is excited by light from the light-emitting element and has at least one emission peak wavelength in a specific wavelength range, and may include two or more phosphors having emission peak wavelengths in different wavelength ranges. The first lead 20 and the second lead 30 connected to a pair of positive and negative electrodes of the light emitting element 10 are partially exposed toward the outside of the package constituting the light emitting device 100. Power can be supplied from the outside via the first lead 20 and the second lead 30, causing the light emitting device 100 to emit light.

[0025] The emission peak wavelength of the light-emitting element 10 is, for example, 400 nm or more, preferably 410 nm or more, more preferably 430 nm or more, and even more preferably 440 nm or more, and is, for example, 490 nm or less, preferably 480 nm or less, more preferably 470 nm or less, and even more preferably 460 nm or less.

[0026] The half width of the emission spectrum of the light emitting element 10 may be, for example, 30 nm or less, 25 nm or less, or 20 nm or less. The half width refers to the full width at half maximum (FWHM) of the maximum emission peak in the emission spectrum, and refers to the wavelength width of the emission peak that shows 50% of the maximum value of the maximum emission peak in each emission spectrum. The light emitting element 10 is made of, for example, a nitride-based semiconductor (In x Al Y Ga 1-X-YN, 0≦X, 0≦Y, X+Y≦1) is preferably used. By using a semiconductor light-emitting element as the light-emitting element, it is possible to obtain a stable light-emitting device that is highly efficient, has high linearity with respect to input, and is resistant to mechanical shock.

[0027] Fluorescent material 50 The fluorescent member 50 includes a phosphor 70 and at least a resin. The fluorescent member 50 includes at least one first phosphor 71 having an emission peak wavelength in the range of 510 nm or more and less than 580 nm due to light emitted from the light emitting element 10, at least one second phosphor 72 having an emission peak wavelength in the range of 580 nm or more and 680 nm or less and having a half-width of 15 nm or more and 100 nm or less in the emission spectrum, and at least one third phosphor 73 having an emission peak wavelength in the range of 600 nm or more and 650 nm or less and having a half-width of 14 nm or less in the emission spectrum. The fluorescent member 50 may include the first phosphor 71, the second phosphor 72, the third phosphor 73, and, if necessary, a fourth phosphor 74, and other phosphors.

[0028] First Phosphor 71 The emission peak wavelength of first phosphor 71 is in the range of 510 nm or more and less than 580 nm, preferably 510 nm or more and 560 nm or less, more preferably 510 nm or more and 540 nm or less, and even more preferably 515 nm or more and 526 nm or less. The half width of the emission spectrum of first phosphor 71 is, for example, 90 nm or more, preferably 92 nm or more, more preferably 95 nm or more, and for example, 125 nm or less, preferably 120 nm or less, more preferably 115 nm or less.

[0029] From the viewpoint of obtaining a desired emission intensity in the emission spectrum of the light emitting device and obtaining an emission spectrum that suppresses melatonin secretion, first phosphor 71 is preferably at least one selected from the group consisting of rare earth aluminate phosphors, scandium-based phosphors, alkaline earth metal silicate phosphors, and lanthanoid silicon nitride phosphors. First phosphor 71 may be used singly or in combination of two or more types.

[0030] The first phosphor 71 is preferably a rare earth aluminate phosphor having a composition represented by the following formula (1A).

[0031] (Ln 1―a Ce a )3(Al 1-b Ga b )5O 12 (1A) In formula (1A), Ln contains at least one rare earth element selected from the group consisting of Y, Gd, Lu and Tb, and a and b are numbers that satisfy 0.001≦a≦0.2 and 0≦b≦1.0, respectively.

[0032] The first phosphor 71 may contain at least one selected from the group consisting of a scandium-based phosphor having a composition represented by the following formula (1B), an alkaline earth metal silicate phosphor having a composition represented by the following formula (1C), and a lanthanoid silicon nitride phosphor having a composition represented by the following formula (1D).

[0033] (Ca,Sr)Sc2O4:Ce (1B) (Ca,Sr)3(Sc,Mg)2Si3O 12 :Ce (1C) (La,Y,Gd)3Si6N 11 :Ce (1D)

[0034] In this specification, in a composition formula, multiple elements separated by a comma (,) mean that at least one element from these multiple elements is contained in the composition. Multiple elements separated by a comma (,) in a composition formula include at least one element selected from the multiple elements separated by the commas in the composition, and may contain a combination of two or more of the multiple elements. In this specification, in a formula representing the composition of a phosphor, the part before the colon (:) represents the host crystal, and the part after the colon (:) represents the activator element.

[0035] The content ratio of the first phosphor to the total amount of phosphors contained in the fluorescent member is preferably 20% by mass or more and 90% by mass or less. When the temperature is 2000K or higher and lower than 2800K, the content ratio of the first phosphor to the total amount of phosphors contained in the fluorescent component is more preferably 30% by mass or higher, even more preferably 35% by mass or higher, and more preferably 80% by mass or lower, even more preferably 70% by mass or lower. When the temperature is 2800K or more and less than 3500K, the content ratio of the first phosphor to the total amount of phosphors contained in the fluorescent component is more preferably 25% by mass or more, even more preferably 30% by mass or more, and more preferably 80% by mass or less, even more preferably 70% by mass or less. When the temperature is 3500K or more and less than 4500K, the content ratio of the first phosphor to the total amount of phosphors contained in the fluorescent component is more preferably 25% by mass or more, even more preferably 30% by mass or more, and more preferably 80% by mass or less, even more preferably 70% by mass or less. When the temperature is 4500K or more and less than 5700K, the content ratio of the first phosphor to the total amount of phosphors contained in the fluorescent component is more preferably 25% by mass or more, even more preferably 30% by mass or more, and more preferably 85% by mass or less, even more preferably 80% by mass or less. When the temperature is 5700K or higher and lower than 7200K, the content ratio of the first phosphor to the total amount of phosphors contained in the fluorescent component is more preferably 20% by mass or higher, even more preferably 25% by mass or higher, and more preferably 85% by mass or lower, even more preferably 80% by mass or lower.

[0036] The average particle size of the first phosphor 71 is, for example, 3 μm or more and 40 μm or less, and preferably 5 μm or more and 35 μm or less. By increasing the average particle size, it is possible to increase the luminous intensity of the first phosphor excited by light emitted from the light emitting element 10. By decreasing the average particle size, it is possible to improve the workability in the manufacturing process of the light emitting device.

[0037] Second Phosphor 72 The second phosphor 72 is excited by the light emitted from the light-emitting element 10 and has an emission peak wavelength within the range of 580 nm or more and 680 nm or less. It is preferable that the second phosphor 72 has an emission peak wavelength in the range of 600 nm or more and 640 nm or less. The full width at half maximum in the emission spectrum of the second phosphor 72 is 15 nm or more, preferably 18 nm or more, more preferably 20 nm or more, 100 nm or less, preferably 95 nm or less, and more preferably 90 nm or less.

[0038] From the viewpoint of obtaining a desired emission intensity in the emission spectrum of the light-emitting device and obtaining an emission spectrum that suppresses melatonin secretion, the second phosphor 72 is, for example, a silicon nitride-based phosphor, an alkaline earth metal silicon nitride-based phosphor, an α-sialon phosphor, a fluorogermanate phosphor, and It is preferably at least one selected from the group consisting of sulfide phosphors. The second phosphor 72 may be used alone or in combination of two or more.

[0039] The second phosphor 72 preferably contains at least one phosphor selected from an alkaline earth metal silicon nitride phosphor having a composition represented by the following formula (2A) or (2B) and an α-sialon phosphor having a composition represented by the following formula (2C).

[0040] Sr s Ca t Al u Si v N w :Eu (2A) In formula (2A), s, t, u, v, and w are numbers that satisfy 0 ≦ s < 1, 0 < t ≦ 1, s + t ≦ 1, 0.9 ≦ u ≦ 1.1, 0.9 ≦ v ≦ 1.1, and 2.5 ≦ w ≦ 3.5, respectively.

[0041] (Ca 1-q-r Sr q Ba r )2Si5N8:Eu (2B) In formula (2B), q and r are numbers that satisfy 0 ≦ q ≦ 1.0, 0 ≦ r ≦ 1.0, and q + r ≦ 1.0, respectively.

[0042] M 4 k Si 12-(m+n) Al m+n O n N 16-n :Eu (2C) In formula (2C), M 4 includes at least one element selected from the group consisting of Li, Mg, Ca, Sr, Y and lanthanoid elements (excluding La and Ce), and k, m and n are numbers satisfying 0 < k ≤ 2.0, 2.0 ≤ m ≤ 6.0, 0 ≤ n ≤ 1.0, respectively.

[0043] The second phosphor 72 may contain at least one selected from the group consisting of a fluorogermanate phosphor having a composition represented by the following formula (2E), a silicon nitride-based phosphor having a composition represented by the following formula (2F), and a sulfide phosphor having a composition represented by the following formula (2G).

[0044] (i - j)MgO·(j / 2)Sc2O3·hMgF2·pCaF2·(1 - z)GeO2·(z / 2)M 6 2O3:Mn (2E) In formula (2E), M 6 includes at least one element selected from the group consisting of Al, Ga and In. i, j, h, p and z are numbers satisfying 2 ≤ i ≤ 4, 0 ≤ j < 0.5, 0 < h < 1.5, 0 ≤ p < 1.5, 0 < z < 0.5, respectively.

[0045] M 7 b1 M 8 c1 Al 3-e1 Si e1 N f1 :M 9 (2F) In formula (2F), M 7 includes at least one element selected from the group consisting of Ca, Sr, Ba and Mg, and M 8 includes at least one element selected from the group consisting of Li, Na and K, and M 9contains at least one element selected from the group consisting of Eu, Ce, Tb, and Mn, and b1, c1, e1, and f1 are numbers that satisfy 0.80≦b1≦1.05, 0.80≦c1≦1.05, 0≦e1≦0.5, and 3.0≦f1≦5.0, respectively.

[0046] (Ca,Sr)S:Eu (2G)

[0047] The content ratio of the second phosphor to the total amount of phosphors contained in the fluorescent member is preferably 0.5% by mass to 15% by mass, and more preferably 1% by mass to 10% by mass.

[0048] The average particle size of the second phosphor 72 is, for example, 1 μm or more and 40 μm or less, and preferably 5 μm or more and 30 μm or less. By increasing the average particle size, it is possible to increase the luminous intensity of the second phosphor excited by light emitted from the light emitting element 10. Furthermore, by decreasing the average particle size, it is possible to improve the workability in the manufacturing process of the light emitting device.

[0049] Third Phosphor 73 Third phosphor 73 is excited by light emitted from light-emitting element 10 and has an emission peak wavelength in the range of 600 nm to 650 nm. It is preferable that third phosphor 73 has an emission peak wavelength in the range of 620 nm to 640 nm due to light emitted from the light-emitting element. The half-width of the emission spectrum of third phosphor 73 is 14 nm or less, preferably 12 nm or less, and more preferably 10 nm or less.

[0050] The third phosphor 73 is preferably a fluoride phosphor having a composition represented by the following formula (3D). A2[M 5 1-a1 Mn 4+ a1 F6] (3D) In formula (3D), A is an alkali metal or ammonium ion It contains at least one selected from the group consisting of, and preferably contains at least potassium. 5It contains at least one element selected from the group consisting of Group 4 elements, Group 13 elements, and Group 14 elements, preferably contains at least one element selected from the group consisting of silicon, aluminum, germanium, and titanium, and more preferably contains at least one element selected from the group consisting of silicon and aluminum. a1 is a number satisfying 0.01 < a1 < 0.2.

[0051] The content ratio of the third phosphor to the total amount of phosphors contained in the fluorescent member is preferably 5% by mass or more and 70% by mass or less. When it is 2000K or more and less than 2800K, the content ratio of the third phosphor to the total amount of phosphors contained in the fluorescent member is more preferably 10% by mass or more, further preferably 20% by mass or more, more preferably 60% by mass or less, further preferably 50% by mass or less, and even more preferably 40% by mass or less. When it is 2800K or more and less than 3500K, the content ratio of the third phosphor to the total amount of phosphors contained in the fluorescent member is more preferably 7% by mass or more, further preferably 10% by mass or more, more preferably 65% by mass or less, further preferably 55% by mass or less, and even more preferably 45% by mass or less. When it is 3500K or more and less than 4500K, the content ratio of the third phosphor to the total amount of phosphors contained in the fluorescent member is more preferably 7% by mass or more, further preferably 10% by mass or more, more preferably 65% by mass or less, further preferably 60% by mass or less, and even more preferably 45% by mass or less. When it is 4500K or more and less than 5700K, the content ratio of the third phosphor to the total amount of phosphors contained in the fluorescent member is more preferably 7% by mass or more, further preferably 10% by mass or more, more preferably 55% by mass or less, further preferably 45% by mass or less, and even more preferably 30% by mass or less. When the temperature is 5700K or higher but lower than 7200K, the content ratio of the third phosphor to the total amount of phosphors contained in the fluorescent component is more preferably 5% by mass or higher, even more preferably 6% by mass or higher, and more preferably 55% by mass or lower, even more preferably 40% by mass or lower, and even more preferably 25% by mass or lower.

[0052] The content ratio of the third phosphor to the total phosphor amount of the second phosphor and the third phosphor is, for example, 60% by mass or more and 99% by mass or less, preferably 65% ​​by mass or more and 98% by mass or less, and more preferably 70% by mass or more and 98% by mass or less.

[0053] The average particle size of the third phosphor 73 is, for example, 1 μm or more and 40 μm or less, and preferably 5 μm or more and 30 μm or less. By increasing the average particle size, it is possible to increase the luminous intensity of the third phosphor excited by light emitted from the light emitting element 10. By decreasing the average particle size, it is possible to improve the workability in the manufacturing process of the light emitting device.

[0054] Quaternary Phosphor 74 The fluorescent member preferably further includes a fourth phosphor having an emission peak in the range of 470 nm or more and 550 nm or less, different from that of the first phosphor. The fourth phosphor 74 has an emission peak wavelength of light emitted from the light-emitting element of, for example, 470 nm or more, preferably 475 nm or more, more preferably 480 nm or more, and for example, 550 nm or less, preferably 540 nm or less, more preferably 530 nm or less, and even more preferably 520 nm or less. As the fourth phosphor, alkaline earth metal aluminate phosphors (hereinafter also referred to as "SAE") having a composition represented by the following formula (4a) and alkaline earth metal chlorosilicate phosphors (hereinafter also referred to as "CMSC") having a composition represented by the following formula (4b) are preferred. (Sr 1-v1 M 1 v1 )4Al 14 O 25 :Eu (4a) In formula (4a), M 1contains at least one element selected from the group consisting of Mg, Ca, Ba and Zn, and v1 is a number that satisfies 0≦v1≦0.5. M 2 8MgSiO 16 X2:Eu (4b) In formula (4b), M 2 contains at least one element selected from the group consisting of Ca, Sr, Ba and Zn, and X contains at least one element selected from the group consisting of F, Cl, Br and I. Examples of the fourth phosphor include a β-sialon phosphor having a composition represented by the following formula (4c), a sulfide phosphor having a composition represented by the following formula (4d) or (4e), and an alkaline earth metal silicate phosphor having a composition represented by the following formula (4f). Si 6-e Al e O e N 8-e :Eu (0 <e≦4.2) (4c) (Sr,M 3 )Ga2S4:Eu (4d) (Sr 1-f-g M 3 f EU g )Ga2S4(4e) In formula (4d) or (4e), M 3 contains at least one element selected from the group consisting of Be, Mg, Ca, Ba, and Zn. In formula (4e), f and g are numbers that satisfy 0.03≦f≦0.25, 0≦g<0.97, and f+g<1. (Ca,Sr,Ba)2SiO4:Eu (4f)

[0055] The half width of the emission spectrum of the fourth phosphor 74 is 20 nm or more, preferably 30 nm or more, more preferably 40 nm or more, and 85 nm or less, preferably 80 nm or less, more preferably 70 nm or less.

[0056] The content ratio of the fourth phosphor to the total amount of phosphors contained in the fluorescent member is preferably 1% by mass or more and 70% by mass or less. When the temperature is 2000K or higher and lower than 2800K, the content ratio of the fourth phosphor to the total amount of phosphors contained in the fluorescent member is more preferably 2% by mass or higher, more preferably 50% by mass or lower, and even more preferably 40% by mass or lower. When the temperature is 2800K or higher and lower than 3500K, the content ratio of the fourth phosphor to the total amount of phosphors contained in the fluorescent member is more preferably 2% by mass or higher, more preferably 50% by mass or lower, and even more preferably 35% by mass or lower. When the temperature is 3500K or more and less than 4500K, the content ratio of the fourth phosphor to the total amount of phosphors contained in the fluorescent member is more preferably 2% by mass or more, more preferably 65% ​​by mass or less, and even more preferably 45% by mass or less. When the temperature is 4500K or more and less than 5700K, the content ratio of the fourth phosphor to the total amount of phosphors contained in the fluorescent member is more preferably 2% by mass or more, more preferably 65% ​​by mass or less, and even more preferably 55% by mass or less. When the temperature is 5700K or higher and lower than 7200K, the content ratio of the fourth phosphor to the total amount of phosphors contained in the fluorescent member is more preferably 2% by mass or higher, more preferably 65% ​​by mass or lower, and even more preferably 60% by mass or lower.

[0057] The average particle size of the fourth phosphor 74 is, for example, 3 μm or more and 40 μm or less, and preferably 5 μm or more and 30 μm or less. By increasing the average particle size, it is possible to increase the luminous intensity of the fourth phosphor excited by light emitted from the light emitting element 10. By decreasing the average particle size, it is possible to improve the workability in the manufacturing process of the light emitting device. In addition to using commercially available phosphors, the third phosphor can be manufactured, for example, by the manufacturing methods described in the applicant's previous patent applications Nos. 2014-202266 and 2020-212532. Other phosphors can also be manufactured, for example, as follows: The raw materials are elemental elements, oxides, carbonates, nitrides, chlorides, fluorides, sulfides, etc., contained in the phosphor composition, and these raw materials are weighed to achieve a predetermined composition ratio. Furthermore, additives such as flux are appropriately added to the raw materials, and the materials are mixed wet or dry using a mixer. This promotes solid-state reactions and allows the formation of particles of uniform size. In addition, the mixer may be a ball mill, which is commonly used industrially, or a grinder such as a vibration mill, roll mill, or jet mill. Grinding using a grinder can also increase the specific surface area. Furthermore, to ensure that the specific surface area of ​​the powder falls within a certain range, classification can be performed using industrially commonly used wet separators such as settling tanks, hydrocyclones, and centrifuges, or dry classifiers such as cyclones and air separators. 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 in a reducing atmosphere containing hydrogen. Firing is performed at a specified temperature and time. The fired material is then crushed, dispersed, filtered, or the like to obtain the desired phosphor powder. Solid-liquid separation can be performed using industrially commonly used methods such as filtration, suction filtration, pressure filtration, centrifugation, and decantation. Drying can be performed using industrially commonly used equipment such as a vacuum dryer, hot air heating dryer, conical dryer, or rotary evaporator.

[0058] The fluorescent member used in the light-emitting device preferably contains a phosphor 70 and a sealing material. Examples of sealing materials include silicone resin and epoxy resin. In addition to the red phosphor and sealing material, the fluorescent member may contain other components such as fillers, light stabilizers, and colorants. Examples of fillers include silica, barium titanate, titanium oxide, and aluminum oxide. The content of other components in the fluorescent member, other than the phosphor and sealing material, varies depending on the desired size of the light-emitting device, the desired correlated color temperature of the mixed color light, and the desired color tone of the mixed color light. The content can be set within a suitable range based on the desired correlated color temperature and color tone. For example, the content of other components in the fluorescent member, other than the phosphor and sealing material, can be 0.01 to 20 parts by mass per 100 parts by mass of the sealing material.

[0059] [Light Emitting Properties] The method for evaluating color rendering properties of light sources is specified in JIS Z8726. Specifically, 15 test colors (numbered 1 to 15) with specified reflectance characteristics are measured using a test light source and a reference light source, and the color difference ΔEi (where i is an integer from 1 to 15) is calculated to calculate the color rendering index. The upper limit of each special color rendering index Ri (where i is an integer from 1 to 15) calculated here is 100, and the smaller the color difference between the test light source and the reference light source with the corresponding color temperature, the closer the value to 100 becomes. Furthermore, of the special color rendering index Ri, R1 to R8 are evaluated as the average color rendering index (hereinafter simply referred to as "Ra"), which is the average of these values, while R9 to R15 are evaluated as individual special color rendering index values. Regarding the special color rendering indexes R9 to R15, R9 is red, R10 is yellow, R11 is green, R12 is blue, R13 is the skin color of Westerners, R14 is the color of leaves, and R15 is the skin color of Japanese people.

[0060] The JIS has published classifications of fluorescent lamps and LEDs based on their light source and color rendering properties (JIS Z9112), which specifies the preferred average color rendering index and specific color rendering index depending on the location of use.

[0061] The light emitting device can achieve Class 1 or Class 2 high color rendering of JIS Z9112. The Ra of the light emitting device is, for example, 80 or more, preferably 85 or more, more preferably 90 or more, and even more preferably 95 or more. The special color rendering index R9 of the light emitting device is, for example, 50 or more, preferably 55 or more, more preferably 70 or more, and even more preferably 80 or more. The special color rendering index R15 is, for example, 70 or more, preferably 85 or more, and more preferably 90 or more.

[0062] The light emitted by the light emitting device can be, for example, light whose chromaticity coordinates as defined in CIE 1931 fall within the ranges of x = 0.28 to 0.55 and y = 0.29 to 0.44, or can also be light whose chromaticity coordinates as defined in CIE 1931 fall within the ranges of x = 0.31 to 0.45 and y = 0.32 to 0.43.

[0063] The correlated color temperature of the light emitted by the light emitting device can be, for example, 2000 K or higher, or 2700 K or higher. The correlated color temperature can also be 7000 K or lower, or 6500 K or lower.

[0064] [Lighting equipment] The lighting fixture may include at least one of the above-described light-emitting devices. Furthermore, the lighting fixture may also include a combination of at least one of the above-described light-emitting devices and a light-emitting device that emits a known white-based mixed color light. In addition to the above-described light-emitting device, the lighting fixture may further include a reflective member, a protective member, an accessory device for supplying power to the light-emitting device, etc. The lighting fixture may also include multiple of the above-described light-emitting devices. When the lighting fixture includes multiple light-emitting devices, the multiple light-emitting devices may be the same, or may include multiple light-emitting devices with different correlated color temperatures, for example. The lighting fixture may also include a driving device that can individually drive the multiple light-emitting devices to adjust the brightness and correlated color temperature to suit the user's preference. The lighting fixture may be used in any of a direct-mounted type, a recessed type, a hanging type, etc. [Example]

[0065] The present invention will be described in more detail below with reference to examples, but the present invention is not limited to these examples.

[0066] First Phosphor 71 As the first phosphor, a rare earth aluminate phosphor having a composition represented by the following formula (1a) (hereinafter also referred to as "G-LAG" or "LAG") and a rare earth aluminate phosphor having a composition represented by the following formula (1b) (hereinafter also referred to as "G-YAG" or "YAG") were prepared. Note that the rare earth aluminate phosphors containing Ga in their composition are referred to as "G-LAG" and "G-YAG", respectively. Lu3(Al,Ga)5O 12 :Ce (1a) Y3(Al,Ga)5O 12 :Ce (1b) The first phosphors shown in Table 1 below were obtained by adjusting the molar ratio of elements (e.g., Ce as an activator) contained in the above composition. The emission peak wavelengths and half-widths of G-LAG, LAG, G-YAG1, G-YAG2, and YAG are shown in Table 1 below.

[0067] [Table 1]

[0068] Second Phosphor 72 As the second phosphor, a silicon nitride phosphor having a composition represented by the following formula (2a) was prepared. (Sr,Ca)AlSiN3:Eu (2a) The second phosphors shown in Table 2 below were obtained by adjusting the molar ratio of elements (e.g., Eu as an activator) contained in the above composition. The emission peak wavelengths and half-widths of SCASN1, SCASN2, SCASN3, and SCASN4 are shown in Table 2 below.

[0069] [Table 2]

[0070] Third Phosphor 73 As the third phosphor, a fluoride phosphor (hereinafter also referred to as "KSF") having a composition represented by K2SiF6:Mn was prepared, which had an emission peak wavelength of 630 nm and a half-value width of 7 nm.

[0071] Quaternary Phosphor 74 As the fourth phosphor, Sr4Al 14 O 25 An alkaline earth metal aluminate phosphor (hereinafter also referred to as "SAE") having a composition represented by the formula: Eu was prepared. In addition, the fourth phosphor is Ca8MgSi4O 16 An alkaline earth metal chlorosilicate phosphor (hereinafter also referred to as "CMSC") having a composition represented by Cl2:Eu was prepared. The fourth phosphors shown in Table 3 below were obtained by adjusting the molar ratio of elements (for example, Eu as an activator) contained in the above composition. The emission peak wavelengths and half widths of SAE, CMSC1, and CMSC2 were as follows: In Table 3 show.

[0072] [Table 3]

[0073] Example 1 The light-emitting device 100 used a nitride semiconductor having an emission peak wavelength of 450 nm as the light-emitting element 10. Silicone resin was used as the sealing material for the fluorescent member 50. A phosphor 70, which contained a first phosphor 71, a second phosphor 72, and a third phosphor 73 blended so that the CIE 1931 chromaticity coordinates were approximately x = 0.458, y = 0.410, was mixed and dispersed with the silicone resin, and then degassed to obtain a resin composition for the fluorescent member. The composition for the fluorescent member was poured onto the light-emitting element 10 in the recess of the molded body 40, filling the recess, and then heated at 150°C for 3 hours to harden the composition for the fluorescent member, forming the fluorescent member 50. The light-emitting device 100 shown in FIG. 1 was manufactured.

[0074] For the light emitting device obtained in Example 1 and each of the light emitting devices in the following Examples and Comparative Examples, the chromaticity coordinates of the emitted color, correlated color temperature (Tcp; K), general color rendering index (Ra (R1 to R8)), and specific color rendering index (R9 to R15) were measured. Specifically, for each of the light emitting devices used in the Examples and Comparative Examples, the chromaticity coordinates (x, y), luminous flux, and radiant flux (total spectral radiant flux) in the chromaticity coordinate system of the CIE 1931 chromaticity diagram were determined using an optical measurement system combining a spectrophotometer (PMA-12, Hamamatsu Photonics K.K.) and an integrating sphere. The results of the chromaticity coordinates of the emitted color and the correlated color temperature (Tcp; K) are shown in Tables 4 to 7. The results of the color rendering index are shown in the following Tables. 4 to 7 The emission spectrum of the light-emitting device was measured using a spectrofluorometer. Figures 4 to 28 show the emission spectra of the light-emitting devices of the examples and comparative examples, normalized to 1 for the emission intensity at the emission peak wavelength of the light-emitting element. The correlated color temperature of the light-emitting device in Example 1 was 2727 K, which is in the range of 2000 K to 2800 K. The melanopic ratio was derived based on the spectral distribution of the light-emitting device, the sensitivity curve (circadian action curve) of ipRGC, a photoreceptor in the mammalian retina proposed by WELL certification, and the luminous efficacy curve for photopic vision of mammals, including humans, as defined by the International Commission on Illumination (CIE), according to the above-mentioned formula (2). The melanopic ratio was calculated using action curves normalized to 1 for the sensitivities at the peak wavelengths of the ipRGC sensitivity curve and the luminous efficacy curve for human photopic vision.

[0075] Examples 2 to 4 and Comparative Example 1 Light emitting devices were fabricated in the same manner as in Example 1, except that the types of first phosphor 71, second phosphor 72, and third phosphor 73 and the content of each phosphor relative to the total amount of phosphors were changed as shown in Table 4 below. The light emitting characteristics of the light emitting devices were measured in the same manner as in Example 1. The correlated color temperature of the light emitting devices in each of the examples and comparative examples was approximately 2700K, which was in the range of 2000K or more and 2800K or less.

[0076] [Table 4]

[0077] Examples 5 to 9 and Comparative Examples 3 and 4 Light-emitting devices were fabricated in the same manner as in Example 1, except that first phosphor 71, second phosphor 72, and third phosphor 73 were blended so that the CIE1931 chromaticity coordinates were approximately x=0.434, y=0.403, and the types of first phosphor 71, second phosphor 72, and third phosphor 73 and the content of each phosphor relative to the total amount of phosphors were changed as shown in Table 5 below. Furthermore, the light-emitting characteristics of the light-emitting devices were measured in the same manner as in Example 1. The correlated color temperature of the light-emitting devices in each of the examples and comparative examples was approximately 3000K, which was within the range of 2800K or higher and lower than 3500K.

[0078] [Table 5]

[0079] Examples 10 to 13 and Comparative Examples 5 and 6 Light emitting devices were fabricated in the same manner as in Example 1, except that first phosphor 71, second phosphor 72, and third phosphor 73 were blended so that the CIE1931 chromaticity coordinates were approximately x=0.382, y=0.380, and the types of first phosphor 71, second phosphor 72, and third phosphor 73 and the content of each phosphor relative to the total amount of phosphors were changed as shown in Table 6 below. Furthermore, the light emitting characteristics of the light emitting devices were measured in the same manner as in Example 1. The correlated color temperature of the light emitting devices in each of the examples and comparative examples was approximately 4000K, which was in the range of 3500K or higher and lower than 4500K.

[0080] [Table 6]

[0081] Examples 14 to 21 and Comparative Examples 7 and 8 Light emitting devices were fabricated in the same manner as in Example 1, except that first phosphor 71, second phosphor 72, and third phosphor 73 were blended so that the CIE1931 chromaticity coordinates were approximately x=0.345, y=0.355, and the types of first phosphor 71, second phosphor 72, and third phosphor 73 and the content of each phosphor relative to the total amount of phosphors were changed as shown in Table 7 below. Furthermore, the light emitting characteristics of the light emitting devices were measured in the same manner as in Example 1. The correlated color temperature of the light emitting devices in each of the examples and comparative examples was approximately 5000K, which was in the range of 4500K or higher and lower than 5700K.

[0082] [Table 7]

[0083] Examples 22 to 25 and Comparative Examples 9 and 10 Light emitting devices were fabricated in the same manner as in Example 1, except that first phosphor 71, second phosphor 72, and third phosphor 73 were blended so that the CIE1931 chromaticity coordinates were approximately x=0.312, y=0.328, and the types of first phosphor 71, second phosphor 72, and third phosphor 73 and the content of each phosphor relative to the total amount of phosphors were changed as shown in Table 8 below. Furthermore, the light emitting characteristics of the light emitting devices were measured in the same manner as in Example 1. The correlated color temperature of the light emitting devices in each of the Examples and Comparative Examples was approximately 6500K, which was within the range of 5700K or higher and lower than 7200K.

[0084] [Table 8]

[0085] As shown in Tables 4 to 8, it was confirmed that the light-emitting devices of Examples 1, 5, 10, 14 to 16, and 22 exhibited higher MR values ​​than the respective comparative examples by combining a light-emitting element having an emission peak at 450 nm with a first phosphor, a second phosphor, and a third phosphor.

[0086] As shown in Tables 4 to 8, it was confirmed that the light-emitting devices of Examples 2 to 4, 6 to 9, 11 to 13, 17 to 21, and 23 to 25 exhibited higher MR values ​​than the respective comparative examples by combining a light-emitting element having an emission peak at 450 nm with a first phosphor, a second phosphor, a third phosphor, and a fourth phosphor.

[0087] Furthermore, Examples 1 to 3, 5 to 8, 10 to 12, 14 to 19, 21, and 22 to 24 had an average color rendering index Ra of 90 or more, a special color rendering index R9 of 50 or more, and a special color rendering index R15 of 85 or more. Furthermore, Examples 4, 9, 13, 20, and 25 were confirmed to have high color rendering properties, with an average color rendering index Ra of 80 or more and a special color rendering index R9 of 50 or more. Furthermore, it was confirmed that efficiency reduction was suppressed compared to the comparative examples.

[0088] For SCASN1, a type of second phosphor, and KSF, a type of third phosphor, the reflectance spectra of the phosphors are shown in FIG. 2, and the emission spectra and visibility spectra are shown in FIG. As shown in Figure 2, SCASN1 has a lower reflectance than KSF in the green wavelength range (wavelength range of approximately 485 nm to approximately 573 nm, see JIS Z8110), meaning that it absorbs more light in the green wavelength range than KSF. Therefore, by using KSF, the phosphor's emission in the green wavelength range can be emitted to the outside of the light-emitting device without being absorbed as much as SCASN1. Furthermore, Figure 3 shows that SCASN1 has more emission components on the long wavelength side (long wavelength side of 630 nm or more) than KSF. KSF has fewer emission components on the relatively long wavelength side, and can reduce components in the wavelength range with low luminosity. Therefore, it is believed that by using KSF and SCASN together, it is possible to suppress the decrease in luminous efficiency despite high color rendering.

[0089] With WELL certification, points are awarded for meeting the standards set by WELL in each category. To ensure color rendering quality, points are awarded for an Ra of 90 or higher, or an Ra of 80 or higher and an R9 of 50 or higher. Examples 1 to 3, 5 to 8, 10 to 12, 14 to 19, 21, and 22 to 24 have an Ra of 90 or higher, while Examples 4, 9, 13, 20, and 25 have an Ra of 80 or higher and an R9 of 50 or higher. Therefore, all of Examples 1 to 25 meet the WELL criteria for points.

[0090] Examples 1 to 25 show high MR values ​​at each color temperature, making them suitable for lighting used during active times. Their high color rendering properties also make them suitable for use in places where precision work is performed. Furthermore, their high special color rendering index R15 makes them suitable for use in hospitals and other situations where face-to-face communication is required.

[0091] 4 to 28 show the emission spectra of the light-emitting devices of Examples and Comparative Examples. In the emission spectra of the light-emitting devices of Examples 1 to 25, a characteristic peak of the third phosphor (KSF) with a half-width of 14 nm or less was confirmed in the range of 600 nm to 650 nm. The emission spectra of the light-emitting devices of Examples 1 to 25 had fewer emission components in the wavelength range of 650 nm or more, where luminosity is low, than the emission spectra of the light-emitting devices of Comparative Examples.

[0092] Generally, a low color temperature results in a low MR value, while a high color temperature results in a high MR value. It is possible to adjust the MR value by changing the color temperature depending on the time of day or purpose of use, such as active or inactive times, but preferred light colors also vary depending on the environment and country of use. It is believed that Examples 1 to 25 can provide a spectrum that exhibits a high MR value while realizing a light color that users find pleasing. [Industrial Applicability]

[0093] The light-emitting device according to the present invention can suppress melatonin secretion and emit light having an emission spectrum that is excellent in workability. For example, it can be used as general lighting installed indoors in offices, ordinary homes, commercial facilities, factories, etc., in vehicles, displays, ornamental lighting, warning lights, security lights, indicator lights, and backlights for liquid crystal displays. Furthermore, it can be used as a lighting fixture equipped with this light-emitting device. [Explanation of symbols]

[0094] 10: light emitting element, 40: molded body, 50: fluorescent member, 70: phosphor, 71: first phosphor, 72: second phosphor, 73: third phosphor, 74: fourth phosphor, 100: light emitting device.

Claims

1. a light-emitting element having an emission peak wavelength in the range of 400 nm to 490 nm; a fluorescent member including: a first phosphor having an emission peak wavelength in the range of 510 nm or more and less than 580 nm; a second phosphor having an emission peak wavelength in the range of 580 nm or more and 680 nm or less and having a half width of 15 nm or more and 100 nm or less in its emission spectrum; and a third phosphor having an emission peak wavelength in the range of 600 nm or more and 650 nm or less and having a half width of 14 nm or less in its emission spectrum; The first phosphor has a composition represented by the following formula (1A): (Ln) 1―ａ Yes ａ ) ３ (Al) １－ｂ Ga ｂ ) ５ O １２ (1A) (In formula (1A), Ln includes at least one element selected from the group consisting of Y, Gd, Lu, and Tb, and a and b are numbers that satisfy 0.001≦a≦0.2 and 0≦b≦1.0, respectively.) The second phosphor has a composition represented by the following formula (2A): Sr ｓ Ca ｔ Al ｕ Yes ｖ N ｗ :Eu (2A) (In formula (2A), s, t, u, v, and w are numbers that satisfy 0≦s<1, 0<t≦1, s+t≦1, 0.9≦u≦1.1, 0.9≦v≦1.1, and 2.5≦w≦3.5, respectively.) The third phosphor has a composition represented by the following formula (3D): A ２ [M ５ １－ａ１ Mn ４＋ ａ１ F ６ ] (3D) (In formula (3D), A contains at least one selected from the group consisting of alkali metals and ammonium ions, and M ５ contains at least one element selected from the group consisting of Group 4 elements, Group 13 elements, and Group 14 elements, and a1 is a number that satisfies 0.01<a1<0.

2. a content ratio of the third phosphor to a total phosphor amount of the second phosphor and the third phosphor is 65% by mass or more and 98% by mass or less; A light-emitting device in which, when the correlated color temperature is within any of the ranges (1) to (5) below, the melanopic ratio (MR) value satisfies the following ranges: (1) When the correlated color temperature is 2000 K or more and less than 2800 K, the MR value is 0.47 or more and 0.73 or less; (2) When the correlated color temperature is 2800 K or more and less than 3500 K, the MR value is 0.53 or more and 0.81 or less; (3) When the correlated color temperature is 3500 K or more and less than 4500 K, the MR value is 0.68 or more and 1.00 or less; (4) When the correlated color temperature is 4500 K or more and less than 5700 K, the MR value is 0.84 or more and 1.18 or less; (5) When the correlated color temperature is 5700K or more and less than 7200K, the MR value is 1.00 or more and 1.40 or less.

2. 2. The light-emitting device according to claim 1, wherein the melanopic ratio (MR) value satisfies the following ranges when the correlated color temperature is in any of the ranges (1') to (5') below. (1') When the correlated color temperature is 2000 K or more and less than 2800 K, the MR value is 0.47 or more and 0.63 or less; (2') When the correlated color temperature is 2800 K or more and less than 3500 K, the MR value is 0.53 or more and 0.71 or less; (3') When the correlated color temperature is 3500 K or more and less than 4500 K, the MR value is 0.68 or more and 0.90 or less; (4') When the correlated color temperature is 4500 K or more and less than 5700 K, the MR value is 0.84 or more and 1.08 or less; (5') When the correlated color temperature is 5700K or more and less than 7200K, the MR value is 1.00 or more and 1.30 or less.

3. The light emitting device according to claim 1 , wherein a content ratio of the first phosphor to a total amount of phosphors contained in the fluorescent member is 20% by mass or more and 90% by mass or less.

4. The light emitting device according to claim 1 , wherein a content ratio of the second phosphor to a total amount of phosphors contained in the fluorescent member is 0.5 mass % or more and 15 mass % or less.

5. The light emitting device according to claim 1 , wherein a content ratio of the third phosphor to a total amount of phosphors contained in the fluorescent member is 5% by mass or more and 70% by mass or less.

6. The light emitting device according to claim 1 , wherein the fluorescent member further includes a fourth phosphor having an emission peak in the range of 470 nm to 550 nm, the emission peak being different from that of the first phosphor.

7. The light emitting device according to claim 6 , wherein the fourth phosphor has at least one composition selected from the following formulas (4a) and (4b): (Mr.) １－ｖ１ M １ ｖ１ ) ４ Al １４ O ２５ :Eu (4a) (In formula (4a), M １ contains at least one element selected from the group consisting of Mg, Ca, Ba, and Zn, and v1 is a number satisfying 0≦v1≦0.

5. M ２ ８ Yes ４ O １６ X ２ :Eu (4b) (In formula (4b), M ２ contains at least one element selected from the group consisting of Ca, Sr, Ba and Zn, and X contains at least one element selected from the group consisting of F, Cl, Br and I.

8. The light emitting device according to claim 6 , wherein a content ratio of the fourth phosphor to a total amount of phosphors contained in the fluorescent member is 1% by mass or more and 70% by mass or less.

9. 9. The light emitting device according to claim 1, wherein the light emitting device has a general color rendering index Ra of 80 or more.

10. 9. The light emitting device according to claim 1, wherein the light emitting device has a general color rendering index Ra of 90 or more.

11. The light emitting device according to claim 1 , wherein the light emitting device has a special color rendering index R9 of 50 or more.

12. The light emitting device according to claim 1 , wherein the light emitting device has a special color rendering index R15 of 85 or more.

13. A lamp comprising the light-emitting device according to any one of claims 1 to 12.

Images