A phosphor having a favorable emission peak wavelength, narrow full width at half maximum, and/or high emission intensity is provided. Additionally, a light-emitting device, an illumination device, an image display device, and/or an indicator lamp for a vehicle having favorable color rendering, color reproducibility and/or favorable conversion efficiency are provided. The present invention relates to a phosphor including a crystal phase having a composition represented by a specific formula, and when, in a powder X-ray diffraction spectrum of the phosphor, the intensity of a peak that appears in a region where 2θ=38-39° is designated as Ix and the intensity of a peak that appears in a region where 2θ=37-38° is designated as Iy, the relative intensity Ix/Iy of Ix to Iy is 0.140 or less, and a light-emitting device comprising the phosphor.

A light source that emits light, wherein, in coordinates in a CIE 1931 chromaticity diagram, the light has a color purity included in a region of 2 to 50 in a region surrounded by a line segment WB and a line segment WG that connect coordinates W (0.33, 0.33) indicating an achromatic color with coordinates B (0.091, 0.133) of 480 nm and coordinates G (0.373, 0.624) of 560 nm on a spectral locus, and the spectral locus, and has an area occupied by a continuous spectral wavelength in a wavelength region of 480 to 540 nm, of 15% or more relative to an area of an overall spectral wavelength of the light source at 380 to 780 nm.

A Cr:YAG sintered body including Al, Y, Cr, Ca, Mg, Si, and O, and component contents in the sintered body satisfying conditional expressions of 1) to 3) below, provided in the Conditional expression, each chemical symbol represents a component content (atppm).
|(Y+Ca)/(Al+Cr+Si+Mg)−0.6|<0.001;  1)
0≤(Ca+Mg)−(Cr+Si)≤50 atppm; and  2)
50≤Si≤500 atppm  3) The embodiment of the present invention is to provide a Cr:YAG sintered body which exhibits high transparency and has a high Cr.sup.4+ conversion ratio, and its production method.

The present invention has an object of providing a wavelength conversion member and a light emitting device which have a high luminescence intensity. A wavelength conversion member 10 contains phosphor particles 2 in a matrix 1 and has a haze value of 0.7 to 0.999 in a visible wavelength range where an excitation spectrum of the phosphor particles 2 shows a spectral intensity of 5% or less of a maximum peak intensity.

A light emitting device includes: a light transmissive member having an upper face, a lower face, and at least one lateral face; a light reflecting member that surrounds the at least one lateral face of the light transmissive member, the light reflecting member being made of a ceramic that contains a plurality of pores; a heat dissipation member disposed under the light reflecting member and the light transmissive member, the heat dissipation member having light transmissivity; and a light emitting element disposed apart from the heat dissipation member in such a manner as to transmit light from the light emitting element through the heat dissipation member and the light transmissive member.

A phosphor having a favorable emission peak wavelength, narrow full width at half maximum, and/or high emission intensity is provided. Additionally, a light-emitting device, an illumination device, an image display device, and/or an indicator lamp for a vehicle having favorable color rendering, color reproducibility and/or favorable conversion efficiency are provided. The present invention relates to a phosphor including a crystal phase having a composition represented by a specific formula, and having a minimum reflectance of 20% or more in a specific wavelength region, in which the specific wavelength region is from the emission peak wavelength of the phosphor to 800 nm, and a light-emitting device comprising the phosphor.

A lighting apparatus includes light emitting elements having an emission peak wavelength of 400 to 510 nm, a first phosphor having an emission peak wavelength of 485 to 700 nm, a second phosphor having an emission peak wavelength of 510 to 590 nm, a third phosphor having an emission peak wavelength of 600 to 700 nm, and a color filter having transmittance for light with a wavelength of 600 to 730 nm that is 80% or more and transmittance for light with a wavelength of 410 to 480 nm that is 3% or more and 50% or less. The color filter transmits a part of light emitted from the first phosphor, at least a part of light emitted from the second phosphor, and at least a part of light emitted from the third phosphor. Light transmitted through the color filter is emitted to the outside.

A phosphor having a favorable emission peak wavelength, narrow full width at half maximum, and/or high emission intensity is provided. Additionally, a light-emitting device, an illumination device, an image display device, and/or an indicator lamp for a vehicle having favorable color rendering, color reproducibility and/or favorable conversion efficiency are provided. The present invention relates to a phosphor including a crystal phase having a composition represented by a specific formula, and having a minimum reflectance of 20% or more in a specific wavelength region, in which the specific wavelength region is from the emission peak wavelength of the phosphor to 800 nm, and a light-emitting device comprising the phosphor.

A polycrystalline YAG sintered body, wherein, when dimensions of a smallest rectangular solid surrounding a YAG sintered body are A mm×B mm×C mm, a maximum value (A, B, C) is 150 mm or less, a minimum value (A, B, C) is more than 20 mm and 40 mm or less, and an optical loss coefficient when light of a wavelength of 300 to 1500 nm (excluding wavelengths which result in absorption of light by an additive element) is transmitted therethrough is 0.002 cm.sup.−1 or less. Moreover, a polycrystalline YAG sintered body, wherein, when dimensions of a smallest rectangular solid surrounding a YAG sintered body are A mm×B mm×C mm, a maximum value (A, B, C) is more than 150 mm and 300 mm or less, a minimum value (A, B, C) is more than 5 mm and 40 mm or less, and an optical loss coefficient when light of a wavelength of 300 to 1500 nm (excluding wavelengths which result in absorption of light by an additive element) is transmitted therethrough is 0.002 cm.sup.−1 or less. An object of an embodiment of the present invention is to provide a large and transparent polycrystalline YAG sintered body and its production method.

A wavelength conversion member converts a wavelength of laser light. The wavelength conversion member includes a substrate having reflectivity with respect to the laser light, and a phosphor layer including a phosphor for converting the laser light into light having a longer wavelength than that of the laser light, the phosphor layer being on the substrate. The phosphor layer includes a plurality of concave parts, each having a depth of 50% or more and 80% or less with respect to a film thickness of the phosphor layer and an opening width of 50 μm or more, on a surface of the phosphor layer, the surface irradiated with the laser light. A distance between adjacent concave parts of the plurality of concave parts is smaller than a spot diameter of the laser light to be emitted to the surface of the phosphor layer.