Abstract: A light emitting device includes a first wavelength converter that converts the primary light into a first wavelength-converted light; and a second wavelength converter that converts the primary light into a second wavelength-converted light. The first wavelength-converted light is a fluorescence having a light component over an entire wavelength range of 700 nm or more to 800 nm or less and having a peak where a fluorescence intensity shows a maximum value in a wavelength range of 700 nm or more, and the second wavelength-converted light is a fluorescence having a peak where a fluorescence intensity shows a maximum value in a wavelength range of 380 nm or more to less than 700 nm. The light emitting device emits a first output light including the first wavelength-converted light and a second output light including the second wavelength-converted light alternately in time.

Abstract: A light emitting device includes a light source configured to emit a primary light, a first phosphor that absorbs the primary light and converts the primary light into a first wavelength-converted light having a wavelength longer than that of the primary light, and a second phosphor that absorbs the primary light and converts the primary light into a second wavelength-converted light having a wavelength longer than that of the primary light. The first wavelength-converted light is a fluorescence having a light component over an entire wavelength range of 700 nm or more to 800 nm or less. The second wavelength-converted light is a fluorescence having a peak where a fluorescence intensity shows a maximum value in a wavelength range of 380 nm or more to less than 700 nm. The first wavelength-converted light has a 1/10 afterglow time longer than that of the second wavelength-converted light.

Abstract: A wavelength converter includes a first phosphor activated with Cr3+; and a second phosphor activated with at least one ion of Ce3+ or Eu2+. A fluorescence spectrum of a fluorescence emitted by the second phosphor has a peak where a fluorescence intensity shows a maximum value in a wavelength range of 500 nm or more to less than 580 nm. The wavelength converter emits a fluorescence having a light component over an entire range of 500 nm or more to less than 580 nm. The wavelength converter emits a light having a spectrum in which a ratio of a minimum light emission intensity to a maximum light emission intensity is 40% or less in a wavelength range of 550 nm or more to 700 nm or less.

Abstract: A light-emitting device includes: a light source that radiates primary light; and a first phosphor that absorbs the primary light and converts the primary light into first wavelength-converted light having a longer wavelength than the primary light, wherein the primary light is laser light, the first wavelength-converted light includes fluorescence based on electron energy transition of Cr3+, and a fluorescence spectrum of the first wavelength-converted light has a maximum fluorescence intensity value in region of a wavelength exceeding 710 nm.

Abstract: Awarm-color complex phosphor includes: a Ce3+-activated orange phosphor that has an excitation peak within a blue wavelength range of 440 nm or more and less than 480 nm and has a fluorescence peak within an orange wavelength range of 580 nm or more and less than 610 nm; and a Ce3+-activated red phosphor that has an excitation peak within a green wavelength range of 500 nm or more and less than 550 nm and has a fluorescence peak within a red wavelength range of 610 nm or more and less than 660 nm. Preferably, the Ce3+-activated red phosphor is a nitride-based compound.

Abstract: A phosphor includes a crystal phase with a chemical composition (LuxY1-x)yM3-y-zCez?p?q. M denotes one or more elements selected from the group consisting of La, Sc, Pr, Nd, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, and Yb. ? contains Si, which constitutes 90% or more by mole of ?. ? contains N, which constitutes 90% or more by mole of ?. The variables x, y, z, p, and q satisfy 0<x?1, 1.5?y?3?z, 0<z?0.6, 5.5?p?6.5, and 10.5?q?11.5. The phosphor has an emission spectrum peak at a wavelength in the range of not less than 600 nm and not more than 680 nm.

Abstract: A fiber light source includes a solid-state light source, a wavelength convertor, and an optical fiber. The solid-state light source is configured to emit first light, the first light including blue light with a peak wavelength in a range of 430 to 470 nm, inclusive, and green light with a peak wavelength in a range of 480 to 550 nm, inclusive. The wavelength convertor is disposed on the light output side or the light incident side of the optical fiber and contains a red phosphor. The red phosphor includes Ce as a luminescent center, and is excited by at least part of the green light to emit second light. The second light has a spectrum with a peak wavelength in a range of 600 to 700 nm, inclusive. The red phosphor contains a nitride or an oxynitride as a host material.

Abstract: A projector includes a light source unit, a spatial light modulator configured to control light from the light source unit for each pixel to form an optical image, and a projection optical system configured to project the optical image formed by the spatial light modulator onto a target. The light source unit includes a solid-state light source and a wavelength convertor. The solid-state light source is configured to emit first light, the first light including blue light with a peak wavelength in a range of 430 to 470 nm, inclusive, and green light with a peak wavelength in a range of 480 to 550 nm, inclusive. The wavelength convertor contains a red phosphor including Ce as a luminescent center that is configured to emit second light upon receiving the green light. The second light has a spectrum with a peak wavelength of 600 to 700 nm, inclusive. The red phosphor contains a nitride or an oxynitride as a host material.

Abstract: A phosphor comprises a crystal phase that has a chemical composition of (Y1-x-y,Cex,Lay)?Si?-zAlzN?O, where the ? satisfies 5.5???6.5, the ? satisfies 9.5???12.5, the ? satisfies 17.5???22.5, the x satisfies 0<x?0.1, the y satisfies 0?y?0.4, and the z satisfies 0?z?0.5. A light emission spectrum of the phosphor includes a peak within a wavelength range of not less than 600 nm and not more than 660 nm.

Abstract: The phosphor according to an aspect of the present disclosure contains a crystal phase having a chemical composition CexYyLa3-x-ySi6N11, where x and y satisfy 0<x?0.6, and (1.5?x)?y?(3?x). The phosphor has an emission spectral peak within a wavelength range of 600 nm or more and 660 nm or less and a first excitation spectral peak within a wavelength range of 480 nm or more and 550 nm or less.

Abstract: A phosphor contains a crystal phase having a chemical composition CexM3-x-y?6?11-z. M is one or more elements selected from the group consisting of Sc, Y, La, Pr, Nd, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb, and Lu. ? contains Si in an amount of 50 mol % or more of a total mol of ?. ? further contains Al. ? contains N in an amount of 80 mol % or more N of a total mol of ?. x satisfies 0<x?0.6. y satisfies 0?y?1.0. z satisfies 0?z?1.0.

Abstract: A light-emitting apparatus includes: a solid-state light source; and a wavelength convertor. The solid-state light source emits first light including green light with a peak wavelength in a range of 480 to 550 nm, inclusive. The wavelength convertor contains a red phosphor including Ce as a luminescent center. The red phosphor is excited by at least part of the green light to emit second light. The second light has a spectrum with a peak wavelength in a range of 600 to 700 nm, inclusive. The red phosphor contains a nitride or an oxynitride as a host material.

Abstract: A phosphor comprises a crystal phase with a chemical composition (Lu1-p-q, Cep, Mq)x?y?zO. M denotes one or more elements selected from the group consisting of Y, La, Sc, Pr, Nd, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, and Yb. ? contains Si, which constitutes 90% or more by mole of ?. ? contains N, which constitutes 90% or more by mole of ?. The variables x, y, z, p, and q satisfy 5.5?x?6.5, 10.5?y?11.5, 19.5?z?20.5, 0<p<0.03, and 0?q?0.5.

Abstract: A light source device includes an excitation light source, and a fluorescence layer configured to emit fluorescence by receiving excitation light emitted from the excitation tight source. The fluorescence layer includes at least one selected from a group consisting of a first fluorescent substance and a second fluorescent substance. The first fluorescent substance is configured to emit fluorescence having a peak wavelength ranging :from 400 nm to 510 nm, inclusive, by receiving the excitation light. The second fluorescent substance is configured to emit fluorescence having a peak wavelength ranging from 580 nm to 700 nm, inclusive, by receiving the excitation light. The first fluorescent substance and the second fluorescent substance each have a fluorescence lifetime ranging from 0.1 nanoseconds to 250 nanoseconds, inclusive. Energy density of the excitation light is 10 W/mm2 or more.

Abstract: A phosphor comprises a crystal phase with a chemical composition (Lu1-p-q, Cep, Mq)x?y?zO. M denotes one or more elements selected from the group consisting of Y, La, Sc, Pr, Nd, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, and Yb. ? contains Si, which constitutes 90% or more by mole of ?. ? contains N, which constitutes 90% or more by mole of ?. The variables x, y, z, p, and q satisfy 5.5?x?6.5, 10.5?y?11.5, 19.5?z?20.5, 0<p<0.03, and 0?q?0.5.

Abstract: A phosphor includes a crystal phase with a chemical composition (LuxY1-x)yM3-y-zCez?p?q. M denotes one or more elements selected from the group consisting of La, Sc, Pr, Nd, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, and Yb. ? contains Si, which constitutes 90% or more by mole of ?. ? contains N, which constitutes 90% or more by mole of ?. The variables x, y, z, p, and q satisfy 0<x?1, 1.5?y?3?z, 0<z?0.6, 5.5?p?6.5, and 10.5?q?11.5. The phosphor has an emission spectrum peak at a wavelength in the range of not less than 600 nm and not more than 680 nm.

Abstract: A phosphor contains a crystal phase having a chemical composition CexM3-x-y?6?11-z. M is one or more elements selected from the group consisting of Sc, Y, La, Pr, Nd, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb, and Lu. ? contains Si in an amount of 50 mol % or more of a total mol of ?. ? further contains Al. ? contains N in an amount of 80 mol % or more N of a total mol of ?. x satisfies 0<x?0.6. y satisfies 0?y?1.0. z satisfies 0?z?1.0.

Abstract: A phosphor contains a crystal phase having a chemical composition CexM3-x-y?6?11-z. M is one or more elements selected from the group consisting of Sc, Y, La, Pr, Nd, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb, and Lu. ? contains Si in an amount of 50 mol % or more of a total mol of ?. ?contains N in an amount of 80 mol % or more N of a total mol of ?. x satisfies 0<x?0.6. y satisfies 0?y?1.0. z satisfies 0?z?1.0. The phosphor shows a maximum peak of an emission spectrum in a wavelength range of 600 nm or more and 800 nm or less and a first peak of an excitation spectrum in a wavelength range of 500 nm or more and 600 nm or less.

Abstract: A light-emitting apparatus includes; a light-emitting device including a photoluminescent layer that receives excitation light and emits light including first light having a wavelength ?a in air, and a light-transmissive layer located on or near the photoluminescent layer; and an optical fiber that receives the light from the photoluminescent layer at one end of the optical fiber and emits the received light from the other end thereof. A surface structure is defined on at least one of the photoluminescent layer and the light-transmissive layer, and the surface structure has projections or recesses or both and limits a directional angle of the first light having the wavelength ?a in air.

Abstract: A light-emitting apparatus includes; a light-emitting device including a photoluminescent layer that receives excitation light and emits light including first light having a wavelength ?a in air, and a light-transmissive layer located on or near the photoluminescent layer; and an optical fiber that receives the light from the photoluminescent layer at one end of the optical fiber and emits the received light from the other end thereof. A surface structure is defined on at least one of the photoluminescent layer and the light-transmissive layer, and the surface structure has projections or recesses or both and limits a directional angle of the first light having the wavelength ?a in air.