Light-emitting device, lighting device, image display device, and display lamp for vehicle

Abstract

The present invention addresses the problem of providing a light-emitting device, an illumination device, an image display device, and / or a display lamp for a vehicle, which are excellent in at least one of color rendering, color reproducibility, conversion efficiency, safety, and contrast. The present invention relates to a light-emitting device which is provided with a light-emitting element that has a first light-emitting body and a second light-emitting body that generates visible light by irradiation with light from the first light-emitting body, and which has at least one or more light-emitting colors having a correlated color temperature of 4000 K or less. The second light-emitting body includes at least one type of phosphor having an emission peak in a wavelength region of 450 nm or more and less than 600 nm, and one or more types of other phosphors having an emission peak wavelength in a wavelength region of 600-700 nm, and in at least one of the emission colors having a correlated color temperature of 4000 K or less, at least one type of phosphor having an emission peak wavelength in a wavelength region of 600-700 nm. C / A is 0.25 or less, where A is the emission intensity at the wavelength [lambda] 1 at which the emission intensity of the emission spectrum is maximum in the range of 600 nm to 700 nm, and C is the emission intensity at the range of 700 nm, and the one or more other phosphors having an emission peak wavelength in the wavelength range of 600 nm to 700 nm include at least the following phosphors containing a crystal phase having a composition represented by a predetermined compositional formula.

Description

Technical Field

[0001] The present invention relates to a light emitting device, a lighting device, an image display device and a display lamp for a vehicle. Background Art

[0002] In recent years, due to the trend of energy saving, the demand for light-emitting devices, lighting devices, image display devices and / or vehicle display lights using LEDs has been increasing. The LEDs used in such devices are, for example, white light-emitting LEDs in which a phosphor is arranged on an LED chip that emits light of a blue or near-ultraviolet wavelength.

[0003] As this type of white light-emitting LED, in recent years, an LED obtained by using a nitride phosphor that emits red light using blue light from the blue LED chip as excitation light and a phosphor that emits green light on a blue LED chip has been used. An LED with high color rendering properties, color reproducibility and / or conversion efficiency is required.

[0004] For example, in lighting applications, a light-emitting device is required that has not only high conversion efficiency but also high color rendering index, displays a light emission spectrum close to natural light so that the color of an object receiving light appears close to natural color, and has low stress on the human eye.

[0005] Prior art literature

[0006] Non-patent literature

[0007] Non-patent document 1: J. Mater. Chem. C, 2015, Vol. 3, Issue 21, p. 5484-5489

[0008] Non-patent document 2: Chemistry Letters, 2006, Vol. 35, No. 3, p. 334-335 Summary of the invention

[0009] In view of the above problems, an object of the present invention is to provide a light-emitting device, a lighting device, an image display device and / or a vehicle display lamp that has good color rendering, color reproducibility, conversion efficiency, safety, and contrast.

[0010] The inventors of the present invention have conducted in-depth research and found that a light-emitting device having a ratio of luminous intensity in a specific range in a plurality of specific wavelength regions or at a specific wavelength can solve the above-mentioned problems, thereby completing the present invention. Some non-limiting embodiments are shown below. It should be noted that the present invention also includes an embodiment that further has a part or all of the features of one or more other embodiments relative to any of the embodiments shown below.

[0011] <1>: A light-emitting device comprising a light-emitting element having at least one luminous color with a correlated color temperature of 4000K or less, the light-emitting element comprising a first luminescent body and a second luminescent body that generates visible light by being irradiated with light from the first luminescent body, the second luminescent body comprising at least one phosphor having a luminous peak in a wavelength region of 450nm to less than 600nm, and at least one other phosphor having a luminous peak wavelength in a wavelength region of 600nm to 700nm, wherein, for at least one of the luminous colors with a correlated color temperature of 4000K or less, when the luminous intensity at the wavelength λ1 where the luminous intensity of the luminous spectrum is maximum in the range of 600nm to 700nm is A and the luminous intensity at 700nm is C, C / A is less than 0.25, and the at least one other phosphor having a luminous peak wavelength in the range of 600nm to 700nm comprises at least the following phosphor, which contains a crystalline phase having a composition represented by the following formula [1].

[0012] Re x MA a MB b MC c N d X e [1]

[0013] (In the above formula [1], MA contains one or more elements selected from Sr, Ca, Ba, Na, K, Y, Gd and La, MB contains one or more elements selected from Li, Mg and Zn, MC contains one or more elements selected from Al, Si, Ga, In and Sc, X contains one or more elements selected from F, Cl, Br and I, Re contains one or more elements selected from Eu, Ce, Pr, Tb and Dy, and a, b, c, d, e, and x satisfy the following formulas respectively.

[0014] 0.7≤a≤1.3

[0015] 0.7≤b≤1.3

[0016] 2.4≤c≤3.6

[0017] 3.2≤d≤4.8

[0018] 0.0≤e≤0.2

[0019] 0.0<x≤0.2)

[0020] <2>: The light-emitting device according to <1> above, wherein, when the light emission intensity at 600 nm is defined as B, B / A is greater than or equal to 0.60.

[0021] <3>: A light-emitting device comprising a light-emitting element having at least one luminous color with a correlated color temperature of 4000K or less, the light-emitting element having a first luminous body and a second luminous body that generates visible light by being irradiated with light from the first luminous body, the second luminous body comprising at least: one or more phosphors having luminous peaks in a wavelength region of greater than 450nm and less than 600nm, and one or more other phosphors having luminous peak wavelengths in a wavelength region of 600nm to 700nm, and for at least one of the luminous colors with a correlated color temperature of 4000K or less, when the luminous intensity at a wavelength λ1 where the luminous intensity of the luminous spectrum in the range of 600nm to 700nm is the largest is set to A, the luminous intensity at 600nm is set to B, and the luminous intensity at 700nm is set to C, B / A is greater than 0.60 and C / A is less than 0.20.

[0022] <4>: A light-emitting device according to any one of <1> to <3> above, wherein, for at least one of the light-emitting colors with the correlated color temperature below 4000K, when the light-emitting intensity at the wavelength λ3 where the light-emitting intensity of the light-emitting spectrum is extremely small in the wavelength region above the light-emitting peak wavelength λ2 of the excitation light is set to D, the ratio D / A of the light-emitting intensity D to the light-emitting intensity A is greater than 0.15.

[0023] <5>: The light-emitting device according to any one of <1> to <4> above is characterized in that, in at least one of the light-emitting colors with the correlated color temperature below 4000K, the light-emitting intensity of the light-emitting spectrum continuously decreases from the wavelength λ1 to 700nm.

[0024] <6>: A light-emitting device according to any one of <1> to <5> above, wherein the proportion of the one or more other phosphors having a light-emitting peak wavelength in the wavelength region of 600nm to 700nm is less than 45 weight % relative to the second light-emitting body.

[0025] <7>: A light emitting device according to any one of <1> to <6>, comprising a plurality of light emitting elements having different luminous colors or color temperatures and a dimming device, capable of displaying two or more luminous colors different from each other.

[0026] <8>: A light-emitting device according to any one of <1> to <7>, wherein the one or more other phosphors having a light-emitting peak wavelength in the wavelength region of 600 nm to 700 nm include a phosphor that substantially does not contain Mn.

[0027] <9>: A light-emitting device according to any one of <1> to <8> above, wherein the one or more other phosphors having a luminescence peak wavelength in the wavelength region of 600nm to 700nm include a phosphor having a luminescence peak wavelength in the wavelength region of 600nm to 648nm.

[0028] <10>: A light-emitting device according to any one of <1> to <9>, comprising one or more other phosphors having a peak emission wavelength in the wavelength region of 600nm to 700nm and having an internal quantum efficiency of 30% or more.

[0029] <11>: A light-emitting device according to any one of <1> to <10> above, comprising a phosphor having a half-width of a light-emitting spectrum of less than 57 nm, and comprising at least one other phosphor having a light-emitting peak wavelength in the wavelength region of 600 nm to 700 nm.

[0030] <12>: A light-emitting device according to any one of <1> to <11> above, comprising a phosphor having a half-width of a light-emitting spectrum of at least one other phosphor having a light-emitting peak wavelength in the wavelength region of 600nm to 700nm and having a wavelength greater than 20nm.

[0031] <13>: A light-emitting device according to any one of <1> to <12> above, comprising one or more other phosphors having a light-emitting peak wavelength in the wavelength region of 600nm to 700nm, wherein the light-emitting peak wavelength x (nm) and the half-width y (nm) of the light-emitting spectrum satisfy the relationship y≤184-0.2x.

[0032] <14>: A light-emitting device according to any one of <1> to <13> above, wherein the at least one other phosphor having a luminescence peak wavelength in the wavelength region of 600nm to 700nm includes at least the following phosphor, which contains a crystalline phase having a composition represented by the following formula [2].

[0033] Re x MA a MB b (Al 1－y MC' y ) c N d X e [2]

[0034] (In the above formula [2], MA contains one or more elements selected from Sr, Ca, Ba, Na, K, Y, Gd and La, MB contains one or more elements selected from Li, Mg and Zn, MC' contains one or more elements selected from Si, Ga, In and Sc, X contains one or more elements selected from F, Cl, Br and I, Re contains one or more elements selected from Eu, Ce, Pr, Tb and Dy, and a, b, c, d, e, x, y respectively satisfy the following formula.

[0035] 0.7≤a≤1.3

[0036] 0.7≤b≤1.3

[0037] 2.4≤c≤3.6

[0038] 3.2≤d≤4.8

[0039] 0.0≤e≤0.2

[0040] 0.0<x≤0.2

[0041] 0.0<y≤1.0)

[0042] <15>: A light-emitting device according to any one of <1> to <14> above, wherein the at least one phosphor having a light-emitting peak in a wavelength region greater than 450 nm and less than 600 nm comprises at least one of a garnet phosphor, a silicate phosphor, a nitride phosphor and a nitrogen oxide phosphor.

[0043] <16>: A lighting device comprising any one of the light-emitting devices described in <1> to <14> as a light source.

[0044] <17>: An image display device comprising any one of the light-emitting devices described in <1> to <14> as a light source.

[0045] <18>: A vehicle indicator light having any one of the light-emitting devices described in <1> to <14> as a light source.

[0046] <19>: A luminescent body comprising at least one phosphor having a luminescence peak in a wavelength region between 450 nm and less than 600 nm and at least one other phosphor having a luminescence peak wavelength in a wavelength region between 600 nm and 700 nm, wherein the luminescent body exhibits a luminescence color having a correlated color temperature of 4000 K or less when excited by blue light, wherein in the luminescence spectrum exhibiting the luminescence color having a correlated color temperature of 4000 K or less, the luminescence intensity at a wavelength λ1 where the luminescence intensity is maximum in the range between 600 nm and 700 nm is set to A, and the luminescence intensity at 700 nm is set to C, and C / A is less than 0.25, wherein the at least one other phosphor having a luminescence peak wavelength in the range between 600 nm and 700 nm comprises at least the following phosphor, which contains a crystalline phase having a composition represented by the following formula [1].

[0047] Re x MA a MB b MC c N d X e [1]

[0048] (In the above formula [1], MA contains one or more elements selected from Sr, Ca, Ba, Na, K, Y, Gd and La, MB contains one or more elements selected from Li, Mg and Zn, MC contains one or more elements selected from Al, Si, Ga, In and Sc, X contains one or more elements selected from F, Cl, Br and I, Re contains one or more elements selected from Eu, Ce, Pr, Tb and Dy, and a, b, c, d, e, and x satisfy the following formulas respectively.

[0049] 0.7≤a≤1.3

[0050] 0.7≤b≤1.3

[0051] 2.4≤c≤3.6

[0052] 3.2≤d≤4.8

[0053] 0.0≤e≤0.2

[0054] 0.0<x≤0.2)

[0055] <20>: The light-emitting body according to <19> above, wherein when the light emission intensity at 600 nm is defined as B, B / A is greater than or equal to 0.60.

[0056] <21>: A luminescent body comprising at least one phosphor having a luminescence peak in a wavelength range of 450 nm to less than 600 nm and at least one other phosphor having a luminescence peak wavelength in a wavelength range of 600 nm to 700 nm,

[0057] When excited by blue light, it displays a luminescent color with a correlated color temperature below 4000K. In the luminescent spectrum displaying the luminescent color with a correlated color temperature below 4000K, when the luminescent intensity at a wavelength λ1 with the maximum luminescent intensity at 600nm to 700nm is set to A, the luminescent intensity at 600nm is set to B, and the luminescent intensity at 700nm is set to C, B / A is greater than 0.60 and C / A is less than 0.20.

[0058] <22>: A luminous body according to any one of <19> to <21> above, wherein, in a luminescent spectrum showing a luminescent color with a correlated color temperature below 4000K, when the luminescent intensity at a wavelength λ3 where the luminescent intensity of the luminescent spectrum is extremely small in a wavelength region above the luminescent peak wavelength λ2 of the excitation light is set to D, the ratio D / A of the luminescent intensity D to the luminescent intensity A is greater than 0.15.

[0059] <23>: A luminescent body according to any one of <19> to <22>, wherein the proportion of one or more other phosphors having a luminescent peak wavelength in the wavelength region of 600nm to 700nm is less than 45% by weight relative to the luminescent body.

[0060] <24>: The luminescent body according to any one of <19> to <23>, wherein the one or more other phosphors having a luminescence peak wavelength in the wavelength region of 600 nm to 700 nm include a phosphor that substantially does not contain Mn.

[0061] <25>: A luminescent body according to any one of <19> to <24> above, wherein the one or more other phosphors having a luminescent peak wavelength in the wavelength region of 600nm to 700nm include a phosphor having a luminescent peak wavelength in the wavelength region of 600nm to 648nm.

[0062] <26>: The luminescent body according to any one of <19> to <25>, comprising one or more other luminescent bodies having a luminescent peak wavelength in the wavelength region of 600 nm to 700 nm and having an internal quantum efficiency of 30% or more.

[0063] <27>: A luminescent body according to any one of <19> to <26>, wherein the luminescent body comprises one or more other luminescent bodies having a luminescent peak wavelength in the wavelength region of 600nm to 700nm, and the half-width of the luminescent spectrum is less than 57nm.

[0064] <28>: A luminescent body according to any one of <19> to <27>, which includes one or more other phosphors having a luminescent peak wavelength in the wavelength region of 600nm to 700nm and has a luminescent spectrum with a half-width of 20nm or more.

[0065] <29>: A luminescent body according to any one of <19> to <28> above, wherein the luminescent peak wavelength x (nm) and the half-width y (nm) of the luminescent spectrum of one or more other phosphors having a luminescent peak wavelength in the wavelength region of 600nm to 700nm satisfy the relationship y≤184-0.2x.

[0066] <30>: A luminescent body according to any one of <19> to <29> above, wherein the one or more other phosphors having a luminescent peak wavelength in the wavelength region of 600nm to 700nm include at least the following phosphor, which contains a crystalline phase having a composition represented by the following formula [2].

[0067] Re x MA a MB b (Al 1－y MC' y ) c N d X e [2]

[0068] (In the above formula [2], MA contains one or more elements selected from Sr, Ca, Ba, Na, K, Y, Gd and La, MB contains one or more elements selected from Li, Mg and Zn, MC' contains one or more elements selected from Si, Ga, In and Sc, X contains one or more elements selected from F, Cl, Br and I, Re contains one or more elements selected from Eu, Ce, Pr, Tb and Dy, and a, b, c, d, e, x, y respectively satisfy the following formula.

[0069] 0.7≤a≤1.3

[0070] 0.7≤b≤1.3

[0071] 2.4≤c≤3.6

[0072] 3.2≤d≤4.8

[0073] 0.0≤e≤0.2

[0074] 0.0<x≤0.2

[0075] 0.0<y≤1.0)

[0076] <31>: A luminescent body according to any one of <19> to <30> above, wherein the at least one phosphor having a luminescence peak in a wavelength region greater than 450 nm and less than 600 nm comprises at least one of a garnet phosphor, a silicate phosphor, a nitride phosphor and a nitrogen oxide phosphor.

[0077] The present invention can provide a light-emitting device, an illumination device, an image display device and / or a vehicle indicator lamp having excellent color rendering performance, color reproducibility, conversion efficiency, safety and contrast in various embodiments. BRIEF DESCRIPTION OF THE DRAWINGS

[0078] Figure 1A This is a graph showing the emission intensities of phosphors 1 to 5 when the emission intensity of the emission peak wavelength of phosphor 1 is set to 1.

[0079] Figure 1B This is a graph showing the emission intensities of phosphor 1 and phosphors 6 to 9 when the emission intensity of the emission peak wavelength of phosphor 1 is set to 1.

[0080] Figure 2 is a graph showing the normalized emission spectra of the reference phosphor and phosphors 1, 2, 5, 8, and 9.

[0081] Figure 3A The figure shows the emission spectrum of the white spectrum having a color temperature of 3000K and CIE chromaticity coordinates (0.437, 0.404) output by simulation in Comparative Example 1, Example 1, and Example 2, which is normalized with the maximum emission intensity at 480 to 780 nm being 1.

[0082] Figure 3B The diagram shows the emission spectrum of the white spectrum having a color temperature of 3000K and CIE chromaticity coordinates (0.437, 0.404) output by simulation in Comparative Example 1, Example 3, and Example 4, which is normalized with the maximum emission intensity at 480 to 780 nm being 1.

[0083] Figure 3C The diagram shows the emission spectra of the white spectrum having a color temperature of 3000K and CIE chromaticity coordinates (0.437, 0.404) output by simulation in Comparative Example 1, Example 5, and Example 6, which are normalized with the maximum emission intensity at 480 to 780 nm being 1.

[0084] Figure 3DThe diagram shows the emission spectra of the white spectrum having a color temperature of 3000K and CIE chromaticity coordinates (0.437, 0.404) output by simulation in Comparative Example 1, Example 7, and Example 8, which are normalized with the maximum emission intensity at 480 to 780 nm being 1.

[0085] Figure 4A Yes Figures 3A to 3D A diagram in which a portion of the luminescence spectra of Comparative Example 1, Example 1, Example 2, Example 4, Example 6 and Reference Example 1 are enlarged.

[0086] Figure 4B Yes Figures 3B to 3D A diagram in which a portion of the emission spectra of Comparative Example 1, Example 3, Example 5, Example 7, and Example 8 are enlarged.

[0087] Figure 5A The diagram shows the emission spectrum of the white spectrum having a color temperature of 4000K and CIE chromaticity coordinates (0.380, 0.377) output by simulation in Comparative Example 2, Example 9, and Example 10, which is normalized with the maximum emission intensity at 480 to 780 nm being 1.

[0088] Figure 5B This is a diagram showing the emission spectrum of the white spectrum with a color temperature of 4000K and CIE chromaticity coordinates (0.380, 0.377) output by simulation in Comparative Example 2, Example 11, and Example 12, after being normalized with the maximum emission intensity at 480 to 780 nm being 1.

[0089] Figure 5C The diagram shows the emission spectrum of the white spectrum having a color temperature of 4000K and CIE chromaticity coordinates (0.380, 0.377) output by simulation in Comparative Example 2, Example 13, and Example 14, which is normalized with the maximum emission intensity at 480 to 780 nm being 1.

[0090] Figure 5D The diagram shows the emission spectrum of the white spectrum having a color temperature of 4000K and CIE chromaticity coordinates (0.380, 0.377) output by simulation in Comparative Example 2, Example 15, and Example 16, which is normalized with the maximum emission intensity at 480 to 780 nm being 1.

[0091] Fig. 6A Yes Figures 5A to 5D A diagram in which a portion of the luminescence spectra of Comparative Example 2, Example 9, Example 10, Example 12, and Example 14 are enlarged.

[0092] Figure 6B Yes Figures 5B to 5DA diagram in which a portion of the luminescence spectra of Comparative Example 2, Example 11, Example 13, Example 15, Example 16 and Reference Example 2 are enlarged. DETAILED DESCRIPTION

[0093] Hereinafter, the present invention will be described by showing embodiments and examples, but the present invention is not limited to the following embodiments and examples, and can be implemented with arbitrary modifications within the scope not departing from the gist of the present invention.

[0094] It should be noted that the numerical range represented by “~” in this specification indicates a range that includes the numerical values ​​recorded before and after “~” as the lower limit and upper limit. In addition, in the composition formula of the phosphor in this specification, the division of each composition formula is represented by a comma (,). In addition, when multiple elements are listed and separated by a comma (,), it means that one or more of the listed elements can be contained in any combination and composition. For example, a composition formula such as “(Ca, Sr, Ba)Al2O4:Eu” generally represents all of the following: “CaAl2O4:Eu”, “SrAl2O4:Eu”, “BaAl2O4:Eu”, “Ca 1－x Sr x Al2O4:Eu", "Sr 1－ x Ba x Al2O4:Eu", "Ca 1－x Ba x Al2O4:Eu" and "Ca 1－x－y Sr x Ba y Al2O4:Eu" (wherein, 0<x<1, 0<y<1, 0<x+y<1).

[0095] In one embodiment, the present invention is a light-emitting device comprising a light-emitting element, the light-emitting element having a first light-emitting body and a second light-emitting body that generates visible light by being irradiated with light from the first light-emitting body, and having at least one luminous color with a correlated color temperature of 4000K or less, the second light-emitting body at least comprising: at least one phosphor having a luminous peak in a wavelength region of 450nm to less than 600nm, and at least one other phosphor having a luminous peak wavelength in a wavelength region of 600nm to 700nm, in at least one of the luminous colors with a correlated color temperature of 4000K or less, when the luminous intensity at the wavelength λ1 where the luminous intensity of the luminous spectrum is maximum in the range of 600nm to 700nm is set to A and the luminous intensity at 700nm is set to C, C / A is less than 0.25, and the at least one other phosphor having a luminous peak wavelength in the wavelength region of 600nm to 700nm at least comprises the following phosphor, which contains a crystalline phase having a composition represented by the following formula [1].

[0096] In addition, in another embodiment of the present invention, there is provided a light-emitting body having the characteristics of the above-mentioned second light-emitting body.

[0097] Re x MA a MB b MC c N d X e [1]

[0098] (In the above formula [1],

[0099] MA contains one or more elements selected from Sr, Ca, Ba, Na, K, Y, Gd and La, MB contains one or more elements selected from Li, Mg and Zn, MC contains one or more elements selected from Al, Si, Ga, In and Sc, X contains one or more elements selected from F, Cl, Br and I, Re contains one or more elements selected from Eu, Ce, Pr, Tb and Dy, and a, b, c, d, e, and x respectively satisfy the following formulas.

[0100] 0.7≤a≤1.3

[0101] 0.7≤b≤1.3

[0102] 2.4≤c≤3.6

[0103] 3.2≤d≤4.8

[0104] 0.0≤e≤0.2

[0105] 0.0<x≤0.2)

[0106] The one or more other phosphors having a light emission peak wavelength in the above-mentioned wavelength region of 600 nm to 700 nm may include at least a phosphor containing a crystal phase having a composition represented by the following formula [2].

[0107] Re x MA a MB b (Al 1－y MC' y ) c N d X e [2]

[0108] (In the above formula [2],

[0109] MA contains one or more elements selected from Sr, Ca, Ba, Na, K, Y, Gd and La, MB contains one or more elements selected from Li, Mg and Zn, MC' contains one or more elements selected from Si, Ga, In and Sc, X contains one or more elements selected from F, Cl, Br and I, Re contains one or more elements selected from Eu, Ce, Pr, Tb and Dy, and a, b, c, d, e, x, y respectively satisfy the following formulas.

[0110] 0.7≤a≤1.3

[0111] 0.7≤b≤1.3

[0112] 2.4≤c≤3.6

[0113] 3.2≤d≤4.8

[0114] 0.0≤e≤0.2

[0115] 0.0<x≤0.2

[0116] 0.0<y≤1.0)

[0117] In the above embodiment, when the light emission intensity at 600 nm is defined as B, B / A may be equal to or greater than 0.60.

[0118] In one embodiment, the present invention is a light-emitting device comprising a light-emitting element, wherein the light-emitting element has a first light-emitting body and a second light-emitting body that generates visible light by being irradiated with light from the first light-emitting body, and has at least one light-emitting color with a correlated color temperature of 4000K or less, wherein the second light-emitting body at least includes: one or more phosphors having a light-emitting peak in a wavelength region of greater than 450nm and less than 600nm, and one or more other phosphors having a light-emitting peak wavelength in a wavelength region of 600nm to 700nm, and in at least one of the light-emitting colors with a correlated color temperature of less than 4000K, when the light-emitting intensity at a wavelength λ1 where the light-emitting intensity of the light-emitting spectrum in the range of 600nm to 700nm is the largest is set to A, the light-emitting intensity at 600nm is set to B, and the light-emitting intensity at 700nm is set to C, B / A is greater than 0.60 and C / A is less than 0.20.

[0119] In one embodiment, the light emitting device has at least one or more luminescent colors with a correlated color temperature of 4000 K or less. The light emitting device may be a device that emits only one color of light with a correlated color temperature of 4000 K or less, or may have two or more luminescent colors. When having two or more luminescent colors, a mechanism may be provided to change the luminescent color continuously or discontinuously by a control device.

[0120] When the B / A is 0.60 or more, a light emitting device having less concavity and convexity in the spectrum and showing a light emission spectrum close to the solar spectrum can be provided. The B / A is preferably 0.70 or more, more preferably 0.75 or more, further preferably 0.80 or more, particularly preferably 0.90 or more, and usually 1.00 or less.

[0121] The C / A is usually 0.25 or less, preferably 0.20 or less, more preferably 0.19 or less, further preferably 0.18 or less, further preferably 0.17 or less, particularly preferably 0.16 or less, and usually 0.01 or more. By making the C / A below the upper limit, a light-emitting device having a reduced contribution from a wavelength region with low relative visual sensitivity and excellent conversion efficiency can be provided.

[0122] In one embodiment, in the light-emitting device, in at least one of the light-emitting colors having the correlated color temperature of 4000K or less, when the light-emitting intensity at the wavelength λ3 where the light-emitting intensity of the light-emitting spectrum is extremely small in the wavelength region of the light-emitting peak wavelength λ2 of the excitation light is set to D, the ratio D / A of the light-emitting intensity D to the light-emitting intensity A is 0.15 or more. When the value of D / A is 0.15 or more, a light-emitting device having a light-emitting spectrum closer to the solar spectrum and high color rendering can be provided.

[0123] The above-mentioned D / A is preferably 0.17 or more, more preferably 0.20 or more, and usually 0.9 or less.

[0124] In one embodiment, the light emitting device is characterized in that, in at least one of the light emitting colors having the correlated color temperature of 4000K or less, the light emitting intensity of the light emitting spectrum decreases continuously from the wavelength λ1 to 700nm. When the light emitting spectrum satisfies the above characteristics, the spectrum shape becomes closer to sunlight, the color rendering property is improved, and the components in the wavelength region with relatively low visual sensitivity are reduced, thereby improving the conversion efficiency.

[0125] In one embodiment, in the above-mentioned light-emitting device, the ratio of the above-mentioned one or more other phosphors having a luminescent peak wavelength in the wavelength region of 600nm to 700nm is 45% by weight or less relative to the above-mentioned second luminous body. The above-mentioned ratio is preferably 40% by weight or less, more preferably 30% by weight or less, and further preferably 25% by weight or less. With this low ratio, a light-emitting device with a high degree of design freedom, such as being able to realize luminescent colors with a smaller amount of phosphors and miniaturizing the size of the light-emitting element, can be provided.

[0126] In one embodiment, the light emitting device comprises a plurality of light emitting elements having different luminous colors or color temperatures and a dimming device. By making such a device, a light emitting device capable of displaying two or more luminous colors different from each other can be provided. That is, in one embodiment, the light emitting device comprises a plurality of light emitting elements having different luminous colors or color temperatures and a dimming device, capable of displaying two or more luminous colors different from each other.

[0127] The dimming device may use an existing dimming device, for example, a control device that controls the voltage applied to different light emitting elements, a switch that independently controls turning on and off the power supply to each light emitting element, or the like.

[0128] In one embodiment, the one or more other phosphors having a peak emission wavelength in the wavelength region of 600 nm to 700 nm include a phosphor that does not substantially contain Mn. In a specific embodiment, the phosphor is composed only of a phosphor that does not substantially contain Mn. By partially or entirely using a phosphor that does not substantially contain Mn as a phosphor, a light-emitting device that reduces or eliminates harmful Mn compounds and is friendly to the human body and the environment can be provided.

[0129] It should be noted that in this specification, a phosphor that "substantially does not contain" a specific component refers to a phosphor that contains the specific component other than as an element constituting the composition of the crystal phase of the phosphor, and to a phosphor that does not contain the specific component as an additive element, activator, etc. A phosphor that "substantially does not contain" a specific component may contain a trace amount of the specific component inadvertently in the form of impurities, etc.

[0130] [Particle size of phosphor]

[0131] In one embodiment, the above-mentioned one or more other phosphors having a luminescence peak wavelength in the wavelength region of 600nm to 700nm include a phosphor whose particle size of the crystalline phase is generally 2μm to 40μm in terms of the volume-based central particle size (volume median particle size), and the lower limit is preferably 3μm, more preferably 4μm, further preferably 5μm, and the upper limit is preferably 35μm, more preferably 30μm, further preferably 25μm, and particularly preferably 20μm.

[0132] When the volume-based central particle size (volume median particle size) is above the above lower limit, it is preferred because the luminescent properties of the crystalline phase in the LED package are improved. When it is below the above upper limit, it is preferred because the crystalline phase can avoid nozzle clogging during the manufacturing process of the LED package.

[0133] The volume-based central particle diameter (volume median particle diameter) of the crystalline phase of the phosphor can be measured using a measurement technique known to those skilled in the art. In a preferred embodiment, for example, a laser particle size analyzer can be used for measurement. In the embodiments of this specification, the volume-based central particle diameter (volume median particle diameter, (d 50 )) is defined as the particle size at which the relative particle amount on a volume basis reaches 50% when the particle size distribution (cumulative distribution) is determined by measuring the sample using a particle size distribution measuring device using the laser diffraction scattering method as the measurement principle.

[0134] {Physical properties of phosphors, etc.}

[0135] [Space Group]

[0136] In one embodiment, the one or more other phosphors having a luminescent peak wavelength in the wavelength region of 600 nm to 700 nm are not limited as long as the effect of the present invention is obtained. In a specific embodiment, the phosphor having a crystal system (space group) of P-1 is included. The space group of the phosphor of this embodiment is not particularly limited as long as the average structure obtained by statistical research within the range that can be distinguished by X-ray powder diffraction or single crystal X-ray diffraction shows a repetition period of the above length, and is preferably a space group belonging to the second type based on "International Tables for Crystallography (Third, revised edition), Volume ASPACE-GROUP SYMMETRY".

[0137] By using the above space group, a phosphor having a narrow half maximum width (FWHM) of a light emission spectrum and good light emission efficiency can be obtained.

[0138] Here, the space group can be determined by a conventional method, for example, by using electron diffraction, X-ray diffraction structure analysis of powder or single crystal, neutron diffraction structure analysis, or the like.

[0139] [Internal quantum efficiency of phosphor]

[0140] In one embodiment, the internal quantum efficiency of the one or more other phosphors having a luminescent peak wavelength in the wavelength region of 600 nm to 700 nm is 30% or more. The internal quantum efficiency is preferably 35% or more, more preferably 40% or more, further preferably 45% or more, particularly preferably 50% or more, further preferably 55% or more, with no upper limit, the higher the better, usually 100%. The quantum efficiency can be obtained by conventional methods, for example, it can be calculated by using a luminescent spectrum measured by a spectrophotometer.

[0141] [Characteristics of luminescence spectrum]

[0142] In one embodiment, the one or more other phosphors having a peak emission wavelength in the wavelength region of 600 nm to 700 nm include a phosphor that emits red light having a good peak emission wavelength and a full width at half maximum (FWHM) of the emission spectrum when excited by irradiation with light having an appropriate wavelength. The emission spectrum and excitation wavelength, the peak emission wavelength, and the full width at half maximum (FWHM) of the emission spectrum are described below.

[0143] (Excitation wavelength)

[0144] In one embodiment, the one or more other phosphors having a luminescence peak wavelength in the wavelength region of 600 nm to 700 nm have an excitation peak in a wavelength range of usually 270 nm or more, preferably 300 nm or more, more preferably 320 nm or more, further preferably 350 nm or more, particularly preferably 400 nm or more, and usually 550 nm or less, preferably 520 nm or less, more preferably 500 nm or less. That is, the phosphors are included that are excited by light in the near ultraviolet to blue region.

[0145] It should be noted that the shape of the luminescence spectrum and the following description of the luminescence peak wavelength and the half-width of the luminescence spectrum can be applied regardless of the excitation wavelength, but from the perspective of improving quantum efficiency, it is preferred to irradiate light with a wavelength in the above range with good absorption and excitation efficiency.

[0146] (Emission peak wavelength)

[0147] In one embodiment, the emission spectrum of the one or more other phosphors having an emission peak wavelength in the wavelength region of 600 nm to 700 nm includes at least one emission peak having an emission peak wavelength of generally 610 nm to 660 nm.

[0148] In another specific embodiment, the above-mentioned one or more other phosphors having a luminescence peak wavelength in the wavelength region of 600nm to 700nm include at least one phosphor that exhibits a luminescence peak wavelength in a wavelength region preferably below 655nm, more preferably below 650nm, further preferably below 648nm, further preferably below 645nm, particularly preferably below 640nm, and extremely preferably below 637nm. In addition, the luminescence peak wavelength of the above-mentioned phosphor is preferably above 610nm, more preferably above 620nm. In a specific embodiment, the above-mentioned one or more other phosphors having a luminescence peak wavelength in the wavelength region of 600nm to 700nm include at least one phosphor that exhibits a luminescence peak wavelength in the wavelength region of 600nm to 648nm.

[0149] A light emitting device including a phosphor having at least one emission peak having an emission peak wavelength equal to or less than the above upper limit has low emission intensity in a wavelength region around 700 nm where relative visual sensitivity is low and good conversion efficiency.

[0150] In addition, by making the emission peak wavelength above the above lower limit, good emission can be obtained in the red region, and a light-emitting device with good red color rendering or color reproducibility can be obtained, so it is suitable for uses such as backlights for image display devices (displays).

[0151] There is no particular limitation on the method for adjusting the peak wavelength of the emission. For example, by adjusting the composition of the MC element, the peak wavelength of the emission can be adjusted while keeping the half-peak width of the emission spectrum narrow. In a specific embodiment, the peak wavelength of the emission can be adjusted to the short wavelength side by increasing the proportion of MC.

[0152] (Half-maximum width of the luminescence spectrum)

[0153] In one embodiment, the above-mentioned one or more other phosphors having a luminescence peak wavelength in the wavelength region of 600nm to 700nm include phosphors whose half-peak width of the luminescence spectrum is usually less than 70nm, preferably less than 65nm, more preferably less than 60nm, further preferably less than 57nm, particularly preferably less than 55nm, most preferably less than 50nm, and usually more than 10nm, preferably more than 20nm, more preferably more than 25nm, and further preferably more than 30nm.

[0154] By using a phosphor having a half-value width of an emission spectrum within the above range, it is possible to expand the color reproduction range without reducing the color purity in an image display device such as a liquid crystal display.

[0155] In addition, by making the emission peak wavelength and the half-width of the emission spectrum below the above-mentioned upper limits, a phosphor with relatively high visual sensitivity in the emission wavelength region can be provided, and by using such a phosphor in a light-emitting device, a light-emitting device with high conversion efficiency can be provided.

[0156] It should be noted that, in order to excite the above-mentioned phosphor with light having a wavelength of about 450nm, for example, a GaN-based LED can be used. In addition, the measurement of the emission spectrum of the above-mentioned phosphor and the calculation of the emission peak wavelength, peak relative intensity and half-peak width of the emission spectrum can be performed using, for example, a commercially available spectrum measuring device such as a fluorescence measuring device equipped with a light source having an emission wavelength of 300 to 400nm such as a xenon lamp and a general light detector.

[0157] In one embodiment, the light-emitting device comprises one or more other phosphors having a peak emission wavelength in the wavelength region of 600 nm to 700 nm, wherein the peak emission wavelength x (nm) and the half-peak width y (nm) of the emission spectrum satisfy the relationship y≤184-0.2x.

[0158] By using a phosphor whose emission peak wavelength and half-peak width satisfy the above formula, the conversion efficiency of the light-emitting device can be optimized.

[0159] <Phosphor>

[0160] There is no particular limitation on the phosphor used in the light-emitting device of the present embodiment as long as the characteristics of the light-emitting device are not impaired, and examples for realizing the invention are given below.

[0161] That is, in one embodiment, the one or more other phosphors having a peak emission wavelength in the wavelength region of 600 nm to 700 nm include at least a phosphor containing a crystal phase having a composition represented by the following formula [1].

[0162] Re x MA a MB b MC c N d X e [1]

[0163] (In the above formula [1],

[0164] MA contains one or more elements selected from Sr, Ca, Ba, Na, K, Y, Gd and La, MB contains one or more elements selected from Li, Mg and Zn, MC contains one or more elements selected from Al, Si, Ga, In and Sc, X contains one or more elements selected from F, Cl, Br and I, Re contains one or more elements selected from Eu, Ce, Pr, Tb and Dy, and a, b, c, d, e, and x respectively satisfy the following formulas.

[0165] 0.7≤a≤1.3

[0166] 0.7≤b≤1.3

[0167] 2.4≤c≤3.6

[0168] 3.2≤d≤4.8

[0169] 0.0≤e≤0.2

[0170] 0.0<x≤0.2)

[0171] In one embodiment, the one or more other phosphors having a light emission peak wavelength in the wavelength region of 600 nm to 700 nm include at least a phosphor containing a crystal phase having a composition represented by the following formula [2].

[0172] Re x MA a MB b (Al 1－y MC' y ) c N d X e [2]

[0173] (In the above formula [2], MA contains one or more elements selected from Sr, Ca, Ba, Na, K, Y, Gd and La, MB contains one or more elements selected from Li, Mg and Zn, MC' contains one or more elements selected from Si, Ga, In and Sc, X contains one or more elements selected from F, Cl, Br and I, Re contains one or more elements selected from Eu, Ce, Pr, Tb and Dy, and a, b, c, d, e, x, y respectively satisfy the following formula.

[0174] 0.7≤a≤1.3

[0175] 0.7≤b≤1.3

[0176] 2.4≤c≤3.6

[0177] 3.2≤d≤4.8

[0178] 0.0≤e≤0.2

[0179] 0.0<x≤0.2

[0180] 0.0<y≤1.0)

[0181] In formula [1] or [2], Re can be europium (Eu), cerium (Ce), praseodymium (Pr), neodymium (Nd), samarium (Sm), terbium (Tb), dysprosium (Dy), holmium (Ho), erbium (Er), thulium (Tm) and ytterbium (Yb). From the viewpoint of improving the emission wavelength and the emission quantum efficiency, Re preferably contains one or more elements selected from Eu, Ce, Pr, Tb and Dy, more preferably contains Eu, further preferably more than 80 mol% of Re is Eu, and further preferably Re is Eu.

[0182] In formula [1] or [2], MA contains one or more elements selected from calcium (Ca), strontium (Sr), barium (Ba), sodium (Na), potassium (K), yttrium (Y), gadolinium (Gd) and lanthanum (La), preferably contains one or more elements selected from Ca, Sr and Ba, and more preferably contains Sr. In addition, preferably, 80 mol% or more of MA is composed of the above preferred elements, and more preferably, MA is composed of the above preferred elements.

[0183] In formula [1] or [2], MB contains one or more elements selected from lithium (Li), magnesium (Mg) and zinc (Zn), preferably contains Li, more preferably 80 mol % or more of MB is Li, and even more preferably MB is Li.

[0184] In formula [1], MC contains one or more elements selected from aluminum (Al), silicon (Si), gallium (Ga), indium (In) and scandium (Sc), preferably contains Al, Ga or Si, more preferably contains Al or Ga, further preferably 80 mol% or more of MC is composed of one or more elements of Al or Ga, particularly preferably 90 mol% or more of MC is composed of one or more elements of Al or Ga, and most preferably MC is composed of one or more elements of Al or Ga.

[0185] With the above configuration, it is possible to make the emission peak wavelength 620 to 660 nm while keeping the half-value width of the phosphor narrow, thereby providing a light-emitting device with excellent conversion efficiency.

[0186] In formula [2], MC' contains one or more elements selected from silicon (Si), gallium (Ga), indium (In) and scandium (Sc), preferably contains Ga or Si, more preferably contains Ga, further preferably more than 80 mol% of MC' is composed of Ga, particularly preferably more than 90 mol% of MC' is composed of Ga, and most preferably MC' is composed of Ga.

[0187] By adopting the above-mentioned structure, the emission wavelength of the above-mentioned phosphor can be set to 648 nm, and a light-emitting device with excellent conversion efficiency can be provided.

[0188] In the formula [1] or [2], N represents nitrogen. In order to maintain the charge balance of the entire crystal phase or to adjust the emission peak wavelength, a part of N may be substituted with oxygen (O).

[0189] In formula [1] or [2], X includes one or more elements selected from fluorine (F), chlorine (Cl), bromine (Br) and iodine (I). That is, in a specific embodiment, from the viewpoint of maintaining the crystalline structure stabilization and the charge balance of the phosphor as a whole, a part of N may be substituted by the above-mentioned halogen element represented by X.

[0190] The above formula [1] or [2] includes the case where it inevitably or unintentionally contains trace amounts of components other than those explicitly described.

[0191] As components other than those explicitly described, there can be mentioned an element having an atomic number different from the artificially added element, an element of the same group as the artificially added element, a rare earth element different from the artificially added rare earth element, a halogen element when a halide is used as the Re raw material, and elements that may generally be contained as impurities in various other raw materials.

[0192] In this specification, "artificially added" specific components refer to intentional addition of specific components as elements constituting the composition of the crystalline phase of the phosphor. Inadvertent mixing of trace amounts of specific components in the form of impurities does not constitute "intentional addition". A phosphor to which a specific component has been artificially added can be said to substantially contain the specific component.

[0193] As the case where components other than those clearly described are inevitably or unintentionally contained, for example, it can be considered that the impurities of the raw materials are introduced during the production process such as the pulverization step and the synthesis step. In addition, as trace added components, reaction aids and Re raw materials can be mentioned.

[0194] In the above formula [1] or [2], a, b, c, d, e, x, and y respectively represent the molar contents of MA, MB, MC, N, X, Re, and MC' contained in the phosphor.

[0195] The value of a is usually 0.6 or more, preferably 0.7 or more, more preferably 0.8 or more, and even more preferably 0.9 or more, and is usually 1.4 or less, preferably 1.3 or less, more preferably 1.2 or less, and even more preferably 1.1 or less.

[0196] The value of b is usually 0.6 or more, preferably 0.7 or more, more preferably 0.8 or more, and even more preferably 0.9 or more, and is usually 1.4 or less, preferably 1.3 or less, more preferably 1.2 or less, and even more preferably 1.1 or less.

[0197] The value of c is usually 2.1 or more, preferably 2.4 or more, more preferably 2.6 or more, and even more preferably 2.8 or more, and is usually 3.9 or less, preferably 3.6 or less, more preferably 3.4 or less, and even more preferably 3.2 or less.

[0198] The value of d is usually 3 or more, preferably 3.2 or more, more preferably 3.4 or more, further preferably 3.6 or more, further preferably 3.8 or more, and usually 5 or less, preferably 4.8 or less, more preferably 4.6 or less, further preferably 4.4 or less, further preferably 4.2 or less.

[0199] The value of e is not particularly limited, but is usually 0 or more, usually 0.2 or less, preferably 0.1 or less, more preferably 0.06 or less, further preferably 0.04 or less, and further preferably 0.02 or less.

[0200] When b, c, d, and e are within the above ranges, the crystal structure is stabilized. In addition, the values ​​of d and e can be appropriately adjusted to maintain the charge balance of the entire phosphor.

[0201] Furthermore, by setting the value of a within the above range, a phosphor having a stabilized crystal structure and few heterophases can be obtained. By having such a red phosphor, a light-emitting device having good absorption efficiency of excitation light and good red and overall conversion efficiency can be provided.

[0202] The value of b+c is usually 3.1 or more, preferably 3.4 or more, more preferably 3.7 or more, and is usually 4.9 or less, preferably 4.6 or less, more preferably 4.3 or less.

[0203] When the value of b+c is within the above range, the crystal structure is stabilized.

[0204] The value of d+e is usually 3.2 or more, preferably 3.4 or more, more preferably 3.7 or more, and is usually 5.0 or less, preferably 4.6 or less, more preferably 4.3 or less.

[0205] When the value of d+e is within the above range, the crystal structure is stabilized.

[0206] When any value is within the above range, the emission peak wavelength and half-value width of the emission spectrum of the obtained phosphor are good, which is preferable.

[0207] The value of x is usually greater than 0, preferably greater than 0.0001, more preferably greater than 0.001, and usually less than 0.2, preferably less than 0.15, more preferably less than 0.12, further preferably less than 0.1, and further preferably less than 0.08. When the value of x is greater than or equal to the above lower limit, a phosphor with good luminous intensity can be obtained. When the value of x is less than the above upper limit, a phosphor in which Re is well introduced into the crystal and easily functions as a luminescent center can be obtained. By having such a phosphor, a light-emitting device with good conversion efficiency can be provided.

[0208] The value of y is greater than 0.0, usually 0.01 or more, preferably 0.015 or more, more preferably 0.03 or more, further preferably 0.05 or more, particularly preferably 0.10 or more, and usually 1.00 or less, preferably 0.70 or less, more preferably 0.50 or less, further preferably 0.30 or less, particularly preferably 0.25 or less.

[0209] When the value of y is equal to or greater than the above lower limit, the peak wavelength of the emission of the phosphor is shortened, and by using such a phosphor, a light-emitting device with good color rendering or color reproducibility can be provided. In addition, when the value of y is equal to or less than the above upper limit, a phosphor with good emission intensity can be obtained, and by using such a phosphor, a light-emitting device with good conversion efficiency can be provided. The value of y can be appropriately adjusted to obtain a preferred emission intensity and peak wavelength according to the purpose.

[0210] The method for determining the elemental composition of the phosphor is not particularly limited and can be determined by a conventional method, for example, by GD-MS, ICP spectrometry or energy dispersive X-ray spectrometry (EDX).

[0211] {Method for producing phosphor}

[0212] A method for obtaining a phosphor containing a crystalline phase having a composition represented by the above formula [1] or [2] used in the above light-emitting device according to a specific embodiment will be described.

[0213] The phosphor of the present embodiment can be synthesized by mixing raw materials of the elements constituting the phosphor so that the ratio of the elements satisfies the above formula [1] or [2], and heating them.

[0214] [raw material]

[0215] The raw materials of each element (MA, MB, MC, MC', MD, Re) are not particularly limited, and examples thereof include single substances, oxides, nitrides, hydroxides, halides such as chlorides and fluorides, inorganic salts such as sulfates, nitrates, and phosphates, and organic acid salts such as acetates. In addition, compounds containing two or more of the above-mentioned element groups may also be used. In addition, each compound may also be a hydrate, etc.

[0216] The method for obtaining each raw material is not particularly limited, and commercially available raw materials can be purchased and used.

[0217] There is no particular restriction on the purity of each raw material. From the perspective of making the element ratio accurate and avoiding the appearance of heterogeneous phases due to impurities, the higher the purity, the better. It is usually 90 mol% or more, preferably 95 mol% or more, more preferably 97 mol% or more, and further preferably 99 mol% or more. There is no particular restriction on the upper limit, which is usually 100 mol%, and may include impurities that are inevitably mixed in.

[0218] In the examples described below, raw materials having a purity of 95 mol % or more were used.

[0219] Oxygen (O), nitrogen (N), and halogen (X) elements can be supplied by using oxides, nitrides, halides, and the like as raw materials of the above-mentioned elements, or can be appropriately contained by setting an atmosphere containing oxygen or nitrogen during the synthesis reaction.

[0220] [Mixing process]

[0221] The mixing method of the raw materials is not particularly limited, and conventional methods can be used. For example, the raw materials are weighed in a manner to obtain the target composition, and a ball mill or the like is used to fully mix to obtain a raw material mixture. As the above-mentioned mixing method, there is no particular limitation, and specifically, the following methods (a) and (b) can be cited.

[0222] (a) A dry mixing method in which the above raw materials are ground and mixed by combining grinding using a dry pulverizer such as a hammer mill, roller mill, ball mill, jet mill, or mortar and pestle with mixing using a mixer such as a screw mixer, V-type mixer, Henschel mixer, or mortar and pestle.

[0223] (b) A wet mixing method in which a solvent or dispersion medium such as water is added to the above raw materials, and the mixture is mixed using, for example, a pulverizer, a mortar and pestle, or an evaporating dish and a stirring rod to prepare a solution or slurry, and then dried by spray drying, heat drying, natural drying, or the like.

[0224] The raw materials may be mixed by either the dry mixing method or the wet mixing method. In order to avoid contamination of the raw materials by water, the dry mixing method or the wet mixing method using a water-insoluble solvent is preferred.

[0225] In addition, the method (a) was adopted in the Examples described later.

[0226] [Heating process]

[0227] In the heating step, for example, the raw material mixture obtained in the mixing step is placed in a crucible and then heated at a temperature of 500°C to 1200°C, preferably 600°C to 1000°C, and more preferably 650°C to 950°C.

[0228] By setting the heating temperature to a low temperature, particularly 950° C. or lower, a phosphor having a high phase purity and high luminous intensity of the composition represented by formula [1] or [2] can be obtained. The reason for this is that at high temperatures such as 1000° C. or higher or 1100° C. or higher, substances containing Li, Mg, Na, etc., which have high vapor pressures, tend to volatilize, and the ratio of each element tends to change during the synthesis reaction of the phosphor. Conversely, by performing the synthesis at a low temperature such as 950° C. or lower, the change in the ratio of each element can be suppressed.

[0229] In addition, the pressure of the heating process can be either normal pressure or pressurized state as long as the target phosphor can be obtained. In order to prevent the volatilization of the raw material elements, it is preferably pressurized. When pressurized, the pressure is usually 0.1MPa to 200MPa, preferably below 100MPa, and more preferably below 50MPa. By keeping the pressure within the above range, good reactivity of the raw materials can be ensured.

[0230] The pressurization method is not limited, and for example, a method of heating a sealed container, a method of mechanically pressurizing, a method of utilizing gas pressure, etc. may be used.

[0231] The material of the crucible is preferably a material that does not react with the raw materials or reactants, and examples thereof include ceramics such as alumina, quartz, boron nitride, silicon carbide, silicon nitride, and metals such as nickel, platinum, molybdenum, tungsten, tantalum, niobium, iridium, and rhodium, or alloys containing these as main components.

[0232] The heating is preferably performed in an inert atmosphere, and a gas having nitrogen, argon, helium or the like as a main component can be used.

[0233] In addition, in the Examples described below, heating was performed under a nitrogen atmosphere.

[0234] In the heating process, heating in the above-mentioned temperature range is usually 10 minutes to 200 hours, preferably 1 hour to 100 hours, more preferably 2 hours to 50 hours, and further preferably 3 to 25 hours. In addition, this heating process can be performed once or divided into multiple times. As a method of dividing into multiple times, there can be cited a method including an annealing process for heating under pressure to repair defects, a method of secondary heating to obtain secondary particles or final products after a primary heating of primary particles or intermediates, etc.

[0235] [Post-processing process]

[0236] The obtained phosphor can be subjected to post-processing such as classification and cleaning by conventional methods.

[0237] For example, a phosphor satisfying the above formula [1] or [2] can be obtained by the above method.

[0238] <Light-emitting device>

[0239] The light-emitting device of this embodiment includes at least one phosphor having a light-emitting peak in the wavelength region of greater than 450 nm and less than 600 nm, and includes at least one of a garnet phosphor, a silicate phosphor, a nitride phosphor, and a nitride oxide phosphor.

[0240] Specifically, when constituting a light-emitting device, as a yellow phosphor, a phosphor having a luminescence peak in a wavelength range of 550 nm to less than 600 nm may be included, and as a green phosphor, a phosphor having a luminescence peak in a wavelength range of 500 nm to 560 nm may be included.

[0241] By appropriately combining the phosphors in the above wavelength regions, a light emitting device showing excellent color reproducibility can be provided. It should be noted that the excitation light source may have an emission peak in a wavelength range of less than 420 nm.

[0242] Hereinafter, as an example of a specific embodiment, a mode of a light-emitting device using one or more phosphors having a light emission peak in a wavelength region of not less than 450 nm and less than 600 nm will be described, but the present embodiment is not limited thereto.

[0243] In the above case, the light emitting device of this embodiment may be in the following form (X), (Y) or (Z), for example.

[0244] (X) A method of using at least one phosphor (yellow phosphor) having a luminescence peak in a wavelength range of greater than 550 nm and less than 600 nm and one or more other phosphors having a luminescence peak wavelength in a wavelength region of 600 nm to 700 nm as the second luminescent body.

[0245] (Y) A method of using at least one phosphor (green phosphor) having a luminescence peak in the wavelength range of 500nm to 560nm and one or more other phosphors having a luminescence peak wavelength in the wavelength region of 600nm to 700nm as the second luminous body.

[0246] (Z) A method of using at least one phosphor (yellow phosphor) having a luminescence peak in a wavelength range of greater than 550 nm and less than 600 nm, at least one phosphor (green phosphor) having a luminescence peak in a wavelength range of 500 nm to 560 nm, and at least one other phosphor having a luminescence peak wavelength in a wavelength region of 600 nm to 700 nm as the second luminescent body.

[0247] As the yellow phosphor and / or green phosphor in the above-mentioned embodiment, commercially available phosphors can be used, for example, garnet phosphors, silicate phosphors, nitride phosphors, oxynitride phosphors, etc. In a specific embodiment, the yellow phosphor and / or green phosphor includes any one or more of garnet phosphors, silicate phosphors, nitride phosphors, and oxynitride phosphors.

[0248] (Yellow phosphor)

[0249] As the garnet-based phosphor that can be used as the yellow phosphor, for example, (Y, Gd, Lu, Tb, La)3(Al, Ga)5O 12 :(Ce, Eu, Nd), as silicate phosphors, for example, (Ba, Sr, Ca, Mg)2SiO4:(Eu, Ce), as nitride phosphors and oxynitride phosphors, for example, (Ba, Ca, Mg)Si2O2N2:Eu (SION phosphors), (Li, Ca)2(Si, Al) 12 (O, N) 16 :(Ce, Eu)(α-sialon phosphor),(Ca, Sr)AlSi4(O, N)7:(Ce, Eu)(1147 phosphor),(La, Ca, Y, Gd)3(Al, Si)6N 11 :(Ce, Eu)(LSN phosphor) etc.

[0250] These may be used alone or in combination of two or more.

[0251] As the yellow phosphor, among the above phosphors, garnet-based phosphors are preferred, and among them, Y3Al5O 12 :YAG-based phosphor represented by Ce.

[0252] (Green phosphor)

[0253] As garnet-based phosphors that can be used as green phosphors, for example, (Y, Gd, Lu, Tb, La)3(Al, Ga)5O 12 :(Ce, Eu, Nd), Ca3(Sc, Mg)2Si3O 12 : (Ce, Eu) (CSMS phosphor), as silicate phosphors, for example, (Ba, Sr, Ca, Mg)3SiO 10 :(Eu, Ce), (Ba, Sr, Ca, Mg)2SiO4:(Ce, Eu)(BSS phosphor), as oxide phosphors, for example, (Ca, Sr, Ba, Mg)(Sc, Zn)2O4:(Ce, Eu)(CASO phosphor), as nitride phosphors and oxynitride phosphors, for example, (Ba, Sr, Ca, Mg)Si2O2N2:(Eu, Ce), Si 6－z Al z O z N 8－z :(Eu, Ce)(β-sialon phosphor)(0<z≤1),(Ba, Sr, Ca, Mg, La)3(Si, Al)6O 12N2: (Eu, Ce) (BSON phosphor), (La, Ca, Y, Gd) 3 (Al, Si) 6 N 11 :(Ce, Eu)(LSN phosphor) etc.

[0254] These may be used alone or in combination of two or more.

[0255] (Red phosphor)

[0256] As the red phosphor, the phosphor of this embodiment having a peak emission wavelength in the wavelength region of 600 nm to 700 nm is used, but in addition to the phosphor of this embodiment, other orange or red phosphors such as garnet phosphors, sulfide phosphors, nanoparticle phosphors, nitride phosphors, and nitrogen oxide phosphors can also be used. As other orange or red phosphors, for example, the following phosphors can be used.

[0257] Examples of sulfide phosphors include (Sr, Ca)S:Eu (CAS phosphor) and La2O2S:Eu (LOS phosphor). Examples of garnet phosphors include (Y, Lu, Gd, Tb)3Mg2AlSi2O3 and (Y, Lu, Gd, Tb)3Mg2AlSi2O4. 12 :Ce, as a nanoparticle phosphor, for example, CdSe can be cited, as a nitride or oxynitride phosphor, for example, (Sr, Ca)AlSiN3:Eu (S / CASN phosphor), (CaAlSiN3) 1－x ·(SiO2N2) x :Eu(CASON phosphor),(La,Ca)3(Al,Si)6N 11 :Eu(LSN phosphor),(Ca,Sr,Ba)2Si5(N,O)8:Eu(258 phosphor),(Sr,Ca)Al 1+x Si 4－x O x N 7－x :Eu(1147 phosphor), M x (Si, Al) 12 (O, N) 16 :Eu (M is Ca, Sr, etc.) (α-sialon phosphor), Li(Sr, Ba)Al3N4:Eu (the above x is 0<x<1), etc.

[0258] These may be used alone or in combination of two or more.

[0259] [Configuration of light emitting device]

[0260] The light-emitting device of this embodiment has a first light-emitting body (excitation light source), and as a second light-emitting body, at least one phosphor having a light-emitting peak in a wavelength region greater than 450nm and less than 600nm and at least one other phosphor having a light-emitting peak wavelength in a wavelength region of 600nm to 700nm can be used. There is no restriction on its structure, and any known device structure can be adopted.

[0261] As the first light-emitting body, an LED element having a light-emitting structure formed in various semiconductors such as GaN-based semiconductors, ZnO-based semiconductors, and SiC-based semiconductors can be used.

[0262] As an embodiment of the device configuration and the light emitting device, for example, there can be cited the embodiment described in Japanese Patent Application Laid-Open No. 2007-291352.

[0263] In addition, the LED element can be fixed in a package such as a shell-type package, an SMD-type package, or can be directly fixed on a circuit substrate like a chip-on-board light-emitting device. There is no limitation on the optical combination of the LED element and the phosphor. The space between the two can be filled only with a transparent medium (including air), or an optical element such as a lens, an optical fiber, a light guide plate, or a reflector can be sandwiched between the two. The structure in which the phosphor particles are dispersed in a translucent matrix is ​​typically formed by curing a resin paste in which particulate phosphors are dispersed. In addition to the structure in which the LED element is embedded in the cured product of such a paste, various structures such as a structure in which the cured product covers a portion of the surface of the LED element in a film-like shape, a structure in which the film composed of the cured product is arranged at a position separated from the LED element, etc. can also be used.

[0264] {Purpose of the light-emitting device}

[0265] The use of the light emitting device is not particularly limited, and the light emitting device can be used in various fields in which light emitting devices are generally used. Among them, a light emitting device with high color rendering index can be particularly suitably used as a light source for a lighting device or an image display device.

[0266] Furthermore, a light emitting device including a red phosphor having a good light emission wavelength can also be used for a red vehicle indicator lamp or a vehicle indicator lamp emitting white light including the red light.

[0267] [lighting device]

[0268] In one embodiment, the present invention may be a lighting device including the above-mentioned light-emitting device as a light source.

[0269] When the light emitting device is used in a lighting device, the specific structure of the lighting device is not limited, as long as the light emitting device described above is appropriately assembled in a known lighting device for use. For example, a surface emitting lighting device having a plurality of light emitting devices arranged on the bottom surface of a holding housing can be cited.

[0270] [Image display device]

[0271] In one embodiment, the present invention may be an image display device including the above-mentioned light-emitting device as a light source.

[0272] When the above-mentioned light-emitting device is used as a light source of an image display device, the specific structure of the image display device is not limited, and it is preferably used together with a color filter. For example, when a color image display device using a color liquid crystal display element is made as an image display device, the image display device can be formed by using the above-mentioned light-emitting device as a backlight and combining a light shutter using liquid crystal with a color filter having red, green, and blue pixels.

[0273] [Vehicle indicator lights]

[0274] In one embodiment, the present invention may be a vehicle indicator lamp including the above-mentioned light emitting device as a light source.

[0275] In a specific embodiment, the light emitting device used in the vehicle indicator lamp is preferably a light emitting device that radiates white light. The light emitting device that radiates white light preferably has a deviation duv (also referred to as Δuv) of the light color of the light emitted by the light emitting device from the black body radiation locus of -0.0200 to 0.0200, and a correlated color temperature of 5000K to 30000K.

[0276] In a specific embodiment, the light emitting device used in the vehicle indicator lamp is preferably a light emitting device that radiates red light. In this embodiment, for example, the light emitting device can absorb blue light irradiated from a blue LED chip and emit red light, thereby providing a red vehicle indicator lamp.

[0277] Vehicle indicator lights include the vehicle's headlights, position lights, taillights, signal lights, brake lights, fog lights, etc., which are used to provide some kind of indication to other vehicles, pedestrians, etc.

[0278] Example

[0279] Hereinafter, some specific embodiments of the present invention will be described by way of examples, but the present invention is not limited to the following contents unless it departs from the gist of the present invention.

[0280] [Measurement of luminescence spectrum]

[0281] The emission spectrum was measured using a fluorescence spectrophotometer FP8500 (manufactured by JASCO Corporation) under the following measurement conditions.

[0282] Light source: Xenon lamp

[0283] Excitation wavelength: 455nm

[0284] ·Measurement wavelength range: 380~780nm

[0285] ·Measurement interval: 1.0nm

[0286] The chromaticity coordinates are calculated from the emission spectrum data of 380 nm to 780 nm using the CIE1931 XYZ equation function.

[0287] [Quantum efficiency measurement]

[0288] The quantum efficiency was calculated based on the emission spectrum measured by a fluorescence spectrophotometer FP8500 (manufactured by JASCO Corporation) under the following measurement conditions.

[0289] Light source: Xenon lamp

[0290] Excitation wavelength: 455nm

[0291] ·Measurement wavelength range: 380~780nm

[0292] ·Measurement interval: 1.0nm

[0293] [Phosphor coordination simulation]

[0294] Based on the information on the measured excitation emission spectrum, internal quantum efficiency and absorption efficiency of the excitation light of each phosphor, a white spectrum that satisfies specific chromaticity coordinates when the spectrum of a blue LED chip emitting 449nm light is combined with an arbitrary phosphor is calculated, and a simulation is performed to estimate the phosphor combination ratio at this time.

[0295] Based on the obtained white spectrum, the luminous flux (Lm) per unit power (Wopt) of the luminous spectrum, namely the spectral efficiency (LER) and the color rendering index of R1 to R15 are calculated.

[0296] <Manufacturing of phosphor>

[0297] [Phosphor 1]

[0298] An exemplary red phosphor used in a light-emitting device according to one embodiment of the present invention or a comparative example is manufactured.

[0299] With reference to Japanese Patent Publication No. 2017-008130 and Chemistry of Materials 2019 31(12), 4614-4618, etc., the nitrides of the elements were mixed in a ratio of Sr:Li:Al of approximately 1:1:3, placed in a boron nitride crucible, sealed, and heated at 1000°C for 5 hours in a nitrogen atmosphere to obtain phosphor 1.

[0300] [Phosphors 2 to 9 and reference phosphors]

[0301] Phosphors 2 to 8 were obtained in the same manner as Phosphor 1 except that a nitride raw material containing Ga was used so that the composition of the phosphor was the composition shown in Table 1 and the calcination temperature was set to 845°C. In addition, a CASN phosphor (BR-101 / J manufactured by Mitsubishi Chemical Corporation) having a peak emission wavelength of 646 nm was prepared as a reference phosphor.

[0302] The characteristics of phosphors 1 to 9 are shown in Table 1, and the emission spectra of each phosphor when excited by light of 449 nm are shown in Figure 1A In addition, the standardized emission spectra of the reference phosphor and phosphors 1, 2, 5, 8, and 9 are shown in Figure 2 .

[0303] It should be noted that the X-ray powder diffraction patterns of phosphors 1 to 9 all showed good consistency with SrLiAl 3 N 4 .

[0304] [Table 1]

[0305]

[0306] <Comparative Example 1, Reference Example 1, Examples 1 to 8>

[0307] Under the assumed conditions of using a SCASN phosphor with a peak emission wavelength of 620 nm (manufactured by Mitsubishi Chemical Corporation, BR-620 / A) not satisfying formula [1] or [2] as the first red phosphor, the phosphors shown in Table 1 or a CASN phosphor with a peak emission wavelength of 646 nm (manufactured by Mitsubishi Chemical Corporation, BR-101 / J) as the second red phosphor, and a LuAG phosphor (manufactured by Mitsubishi Chemical Corporation, BG-801 / B4) as the green phosphor, the amounts of the green phosphor and the first and second red phosphors were adjusted in a manner such that the CIE chromaticity coordinates were consistent with the coordinates (0.437, 0.404) of 3000K white light on the blackbody curve, based on the above-mentioned phosphor combination simulation method, on the basis of satisfying the average color rendering evaluation number Ra of 90 or more, to obtain a white emission spectrum, and the characteristics of the above white emission spectra were compared.

[0308] The white light emission spectra of the white LEDs of Comparative Example 1 and Examples 1 to 8 are normalized by setting the maximum light emission intensity in the wavelength region of 480 nm to 780 nm to 1. Figures 3A to 3D In addition, Figures 3A to 3D The emission spectrum shown in FIG. 1 and the enlarged spectrum of the emission spectrum of the white LED of Reference Example 1 similarly depicted are shown in FIG. Figure 4A , 4B In addition, Table 2 shows the results of calculating the light emission characteristics from each spectrum.

[0309] <Comparative Example 2, Reference Example 2, Examples 9 to 16>

[0310] Next, as Comparative Example 2, Examples 9 to 16, and Reference Example 2, simulations were performed in the same manner as in Comparative Example 1, Reference Example 1, and Examples 1 to 8, except that the CIE chromaticity coordinates were made consistent with the coordinates (0.380, 0.377) of 4000K white light on the blackbody curve.

[0311] The white light emission spectra of the white LEDs of Comparative Example 2 and Examples 9 to 16 are normalized by setting the maximum light emission intensity in the wavelength region of 480 nm to 780 nm to 1. Figures 5A to 5D In addition, Figures 5A to 5D The luminous spectrum shown in and the enlarged spectrum of the luminous spectrum of the white LED of Reference Example 2 similarly depicted are shown in Fig. 6A , 6B In addition, the results of calculating the luminescence characteristics from each spectrum are shown in Table 3.

[0312] It should be noted that “700nm / 600-700nm maximum value” and “600nm / 600-700nm maximum value” in Tables 2 and 3 represent the relative values ​​of the luminous intensities at 700nm and 600nm when the maximum luminous intensity in the wavelength region of 600 to 700nm in each luminescent spectrum is set to 1.

[0313] In addition, the "ratio / wt%" of the phosphors in Tables 2 and 3 refers to the weight ratio of each phosphor when the total weight of each phosphor is set to 100%, "Green" is the above-mentioned LuAG phosphor, "Red 1" is the above-mentioned first red phosphor, and "Red 2" is the above-mentioned second red phosphor.

[0314] [Table 2]

[0315]

[0316] [Table 3]

[0317]

[0318] Example 1 maintains LER almost equal to that of Reference Example 1, while improving R9, and it is found that the color rendering of red is improved. The same trend is also seen in the comparison between Example 9 and Reference Example 2.

[0319] The white LEDs of Examples 1 to 8 are compared with the white LEDs of Comparative Example 1 and Reference Example 1, and the white LEDs of Examples 9 to 16 are compared with the white LEDs of Comparative Example 2 and Reference Example 2. It can be seen that white light with greatly improved LER can be provided within the standards of Ra≥90 and R9≥50.

[0320] In addition, it can be seen from the figure that the light-emitting device of the present invention has a sharp peak in the red region, and can suppress the luminous intensity in wavelength regions such as 700nm where the visual sensitivity is relatively low, thereby providing a light-emitting device with high color rendering or red color reproducibility and high conversion efficiency.

[0321] In summary, according to the present embodiment, a phosphor having a good luminous peak wavelength, a narrow half-peak width of the luminous spectrum and / or a high luminous intensity can be provided. In addition, by having the phosphor, a light-emitting device, a lighting device, an image display device and / or a vehicle display light having good color rendering or color reproducibility and good conversion efficiency can be provided.

[0322] Although various embodiments have been described above with reference to the accompanying drawings, the present invention is certainly not limited to the above examples. For those skilled in the art, various variations or modifications can be thought of within the scope of the claimed scope, and this is clear, and it can be understood that they certainly also belong to the technical scope of the present invention. In addition, the various constituent elements in the above embodiments can be arbitrarily combined within the scope of the invention without departing from the gist of the invention.

[0323] It should be noted that the present application is based on the Japanese patent application (Japanese Patent Application No. 2022-210189) filed on December 27, 2022, and the contents thereof are incorporated herein by reference.

[0324] Industrial Applicability

[0325] The light-emitting device of the present invention has excellent color rendering, color reproducibility, conversion efficiency, safety, and contrast, and can therefore be used in lighting devices, image display devices, vehicle indicator lights, and the like.

Claims

1. A light-emitting device comprising a light-emitting element having at least one luminous color with a correlated color temperature of 4000K or less, wherein the light-emitting element comprises a first luminous body and a second luminous body that generates visible light when irradiated with light from the first luminous body, The second luminous body at least comprises: one or more phosphors having a luminescence peak in a wavelength range of 450 nm to less than 600 nm, and one or more other phosphors having a luminescence peak wavelength in a wavelength range of 600 nm to 700 nm. In at least one of the luminescent colors having a correlated color temperature of 4000K or less, when the luminescent intensity at the wavelength λ1 where the luminescent intensity of the luminescent spectrum in the range of 600nm to 700nm is the maximum is set as A and the luminescent intensity at 700nm is set as C, C / A is less than 0.25, The one or more other phosphors having a peak emission wavelength in the wavelength region of 600 nm to 700 nm include at least: a phosphor containing a crystalline phase having a composition represented by the following formula [1], Re x MA a MB b MC c N d X e [1] In the formula [1], MA contains one or more elements selected from Sr, Ca, Ba, Na, K, Y, Gd and La, MB contains one or more elements selected from Li, Mg and Zn, MC contains one or more elements selected from Al, Si, Ga, In and Sc, X contains one or more elements selected from F, Cl, Br and I, Re contains one or more elements selected from Eu, Ce, Pr, Tb and Dy, and a, b, c, d, e, x respectively satisfy the following formula: 0.7≤a≤1.3 0.7≤b≤1.3 2.4≤c≤3.6 3.2≤d≤4.8 0.0≤e≤0.2 0.0＜x≤0.2。 2. The light emitting device according to claim 1, wherein: When the emission intensity at 600 nm is defined as B, B / A is 0.60 or more.

3. A light-emitting device comprising a light-emitting element having at least one luminous color with a correlated color temperature of 4000K or less, wherein the light-emitting element comprises a first luminous body and a second luminous body that generates visible light when irradiated with light from the first luminous body, The second luminous body at least comprises: one or more phosphors having a luminescence peak in a wavelength range of 450 nm to less than 600 nm, and one or more other phosphors having a luminescence peak wavelength in a wavelength range of 600 nm to 700 nm. In at least one of the luminescent colors with a correlated color temperature below 4000K, when the luminescent intensity at the wavelength λ1 where the luminescent intensity of the luminescent spectrum in the range of 600nm to 700nm is the largest is set to A, the luminescent intensity at 600nm is set to B, and the luminescent intensity at 700nm is set to C, B / A is greater than 0.60 and C / A is less than 0.

20.

4. The light emitting device according to claim 1 or 3, wherein: For at least one of the luminous colors with a correlated color temperature below 4000K, when the luminous intensity at the wavelength λ3 where the luminous intensity of the luminous spectrum is extremely small in the wavelength region above the luminous peak wavelength λ2 of the excitation light is set to D, the ratio D / A of the luminous intensity D to the luminous intensity A is greater than 0.

15.

5. The light emitting device according to claim 1 or 3, characterized in that: In at least one of the emission colors having a correlated color temperature of 4000 K or less, the emission intensity of the emission spectrum decreases continuously from the wavelength λ1 to 700 nm.

6. The light emitting device according to claim 1 or 3, wherein: The ratio of the one or more other phosphors having a light emission peak wavelength in the wavelength region of 600 nm to 700 nm to the second light-emitting body is 45% by weight or less.

7. The light emitting device according to claim 1 or 3, wherein: A plurality of light emitting elements having different luminous colors or color temperatures and a dimming device can display two or more luminous colors that are different from each other.

8. The light emitting device according to claim 1 or 3, wherein: The one or more other phosphors having a light emission peak wavelength in the wavelength region of 600 nm to 700 nm include a phosphor that does not substantially contain Mn.

9. The light emitting device according to claim 1 or 3, wherein: The one or more other phosphors having a light emission peak wavelength in the wavelength region of 600 nm to 700 nm include a phosphor having a light emission peak wavelength in the wavelength region of 600 nm to 648 nm.

10. The light emitting device according to claim 1 or 3, wherein: A phosphor having an internal quantum efficiency of 30% or more containing one or more other phosphors having a light emission peak wavelength in the wavelength region of 600 nm to 700 nm.

11. The light emitting device according to claim 1 or 3, wherein: A phosphor having a half-value width of a light emission spectrum of 57 nm or less, comprising at least one other phosphor having a light emission peak wavelength in the wavelength region of 600 nm to 700 nm.

12. The light emitting device according to claim 1 or 3, wherein: A phosphor containing at least one other phosphor having a light emission peak wavelength in the wavelength region of 600 nm to 700 nm, wherein the half-value width of the light emission spectrum is 20 nm or more.

13. The light emitting device according to claim 1 or 3, wherein: A phosphor comprising one or more other phosphors having a luminescence peak wavelength in the wavelength region of 600nm to 700nm, wherein the luminescence peak wavelength x and the half-peak width y of the luminescence spectrum satisfy the relationship y≤184-0.2x, wherein the units of the luminescence peak wavelength x and the half-peak width y are nm.

14. The light emitting device according to claim 1 or 3, wherein: The one or more other phosphors having a peak emission wavelength in the wavelength region of 600 nm to 700 nm include at least: a phosphor containing a crystalline phase having a composition represented by the following formula [2], Re x MA a MB b (Al 1－y MC' y ) c N d X e [2] In the formula [2], MA contains one or more elements selected from Sr, Ca, Ba, Na, K, Y, Gd and La, MB contains one or more elements selected from Li, Mg and Zn, MC' contains one or more elements selected from Si, Ga, In and Sc, X contains one or more elements selected from F, Cl, Br and I, Re contains one or more elements selected from Eu, Ce, Pr, Tb and Dy, and a, b, c, d, e, x, y respectively satisfy the following formula: 0.7≤a≤1.3 0.7≤b≤1.3 2.4≤c≤3.6 3.2≤d≤4.8 0.0≤e≤0.2 0.0＜x≤0.2 0.0＜y≤1.0。 15. The light emitting device according to claim 1 or 3, wherein: The one or more phosphors having a light emission peak in a wavelength region of not less than 450 nm and less than 600 nm include any one or more of a garnet phosphor, a silicate phosphor, a nitride phosphor, and a nitride oxide phosphor.

16. A lighting device comprising the light-emitting device according to claim 1 or 3 as a light source.

17. An image display device comprising the light emitting device according to claim 1 or 3 as a light source.

18. A vehicle indicator lamp comprising the light emitting device according to claim 1 or 3 as a light source.

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