Abstract: Provided is a wavelength conversion member capable of improving brightness of a light source device. Wavelength conversion member according to the present disclosure includes: first phosphor layer that is disposed on an incidence side where excitation light enters, and contains a plurality of first phosphor particles; and second phosphor layer that is disposed on a side reverse to the incidence side and contains a plurality of second phosphor particles. First phosphor particles include an activation component, second phosphor particles include an activation component same as or different from the activation component included in first phosphor particles, and a concentration of the activation component in first phosphor layer is lower than a concentration of the activation component in second phosphor layer.

Abstract: An oxide insulator film contains a first metal oxide and a second metal oxide. An electrical conductivity of the second metal oxide is lower than an electrical conductivity of the first metal oxide. The oxide insulator film includes particles of the first metal oxide which are dispersed in a matrix including the second metal oxide.

Abstract: A conductive paste for an electrolytic capacitor used for connecting a cathode part and a cathode lead terminal of the electrolytic capacitor. The conductive paste includes a thermosetting resin, and conductive particles, and the conductive particles include flaky metal particles and acicular conductive particles. The content of the conductive particles in the conductive paste is, for example, 50 mass % or more and 70 mass % or less, and the mass ratio of the flaky metal particles to the total of the flaky metal particles and the acicular conductive particles is, for example, 60% or more and 80% or less.

Abstract: A wavelength conversion device includes a matrix containing inorganic material, a phosphor embedded in the matrix, and filler particles embedded in the matrix and containing resin material. This wavelength conversion device prevents the phosphor from falling.

Abstract: A wavelength conversion device includes a substrate, a matrix supported by the substrate and containing inorganic material, a phosphor embedded in the matrix, and filler particles embedded in the matrix. A linear expansion coefficient of the filler particles is equal to or larger than 25 ppm/K and equal to or smaller than 790 ppm/K, and is larger than a linear expansion coefficient of the matrix. This wavelength conversion device suppresses warping of the substrate.

Abstract: Provided is a technique for suppressing a temperature rise of a wavelength conversion member. The present disclosure is provided with: phosphor layer containing a phosphor; substrate that supports phosphor layer; and heat sink bonded to substrate, wherein the thermal conductivity of substrate is greater than the thermal conductivity of phosphor layer, and the thermal conductivity of heat sink is greater than the thermal conductivity of substrate, or the thermal conductivity of heat sink is smaller than the thermal conductivity of substrate.

Abstract: A wavelength conversion device includes a matrix containing inorganic material, a phosphor embedded in the matrix, and filler particles embedded in the matrix and containing resin material. This wavelength conversion device prevents the phosphor from falling.

Abstract: A wavelength conversion device includes a substrate, a matrix supported by the substrate and containing inorganic material, a phosphor embedded in the matrix, and filler particles embedded in the matrix. A linear expansion coefficient of the filler particles is equal to or larger than 25 ppm/K and equal to or smaller than 790 ppm/K, and is larger than a linear expansion coefficient of the matrix. This wavelength conversion device suppresses warping of the substrate.

Abstract: A wavelength conversion device of the present disclosure includes a substrate, a phosphor layer that has a matrix containing zinc oxide and phosphor particles embedded in the matrix and that is supported by the substrate, a dielectric layer disposed between the substrate and the phosphor layer, and a protective layer that is disposed between the phosphor layer and the dielectric layer and that has an isoelectric point equal to or larger than 7. A main surface of the substrate includes, for example, first and second regions. The phosphor layer covers, for example, only the first region out of the first and second regions.

Abstract: Provided is a wavelength conversion member capable of improving brightness of a light source device. Wavelength conversion member according to the present disclosure includes: first phosphor layer that is disposed on an incidence side where excitation light enters, and contains a plurality of first phosphor particles; and second phosphor layer that is disposed on a side reverse to the incidence side and contains a plurality of second phosphor particles. First phosphor particles include an activation component, second phosphor particles include an activation component same as or different from the activation component included in first phosphor particles, and a concentration of the activation component in first phosphor layer is lower than a concentration of the activation component in second phosphor layer.

Abstract: A light source device includes: an excitation light source that emits excitation light having an energy density of 10 W/mm2 or more; and a phosphor layer that has phosphor particles embedded in the matrix. The phosphor particles include at least one selected from the group consisting of metal oxides represented by a following formula (1) and metal oxides represented by a following formula (2). Y3-x1-y1R1y1Cex1Al5-z1Gaz1O12??(1) Y3-x2-y2R2y2Cex2Al5-z2Scz2O12??(2) In the formula (1), R1 includes at least one selected from the group consisting of Gd and Tb, and x1, y1, and z1 satisfy 0.003?x1?0.03, 0?y1?2.1, and 0?z1?2.2, respectively. In the formula (2), R2 includes at least one selected from the group consisting of Gd and Tb, and x2, y2, and z2 satisfy 0.003?x2?0.03, 0?y2?2.1 and 0?z2?1.5, respectively.

Abstract: Provided is a wavelength conversion member exhibiting high reliability. A wavelength conversion member includes a phosphor layer having a matrix containing ZnO and phosphor particles embedded in the matrix and a first protective layer that contains at least one selected from the group of ZnCl2, ZnS and ZnSO4 and covers the phosphor layer. For example, the first protective layer is in contact with the phosphor layer. For example, ZnO is c-axis-oriented polycrystalline ZnO.

Abstract: A light source device includes: an excitation light source that emits excitation light having an energy density of 10 W/mm2 or more; and a phosphor layer that has phosphor particles embedded in the matrix. The phosphor particles include at least one selected from the group consisting of metal oxides represented by a following formula (1) and metal oxides represented by a following formula (2). Y3-x1-y1R1y1Cex1Al5-z1Gaz1O12??(1) Y3-x2-y2R2y2Cex2Al5-z2Scz2O12??(2) In the formula (1), R1 includes at least one selected from the group consisting of Gd and Tb, and x1, y1, and z1 satisfy 0.003?x1?0.03, 0?y1?2.1, and 0?z1?2.2, respectively. In the formula (2), R2 includes at least one selected from the group consisting of Gd and Tb, and x2, y2, and z2 satisfy 0.003?x2?0.03, 0?y2?2.1 and 0?z2?1.5, respectively.

Abstract: A wavelength conversion device of the present disclosure includes a substrate, a phosphor layer that has a matrix containing zinc oxide and phosphor particles embedded in the matrix and that is supported by the substrate, a dielectric layer disposed between the substrate and the phosphor layer, and a protective layer that is disposed between the phosphor layer and the dielectric layer and that has an isoelectric point equal to or larger than 7. A main surface of the substrate includes, for example, first and second regions. The phosphor layer covers, for example, only the first region out of the first and second regions.

Abstract: A wavelength conversion member of the present disclosure includes a first matrix, phosphor particles embedded in the first matrix, and at least one selected from the group consisting of first filler particles embedded in the first matrix and surface coating layers respectively covering surfaces of the phosphor particles. The wavelength conversion member satisfies at least one relationship selected from the group consisting of |n3?n1|>|n1?n2| and |n4?n1|>|n1?n2| wherein n1 is a refractive index of the first matrix, n2 is a refractive index of the phosphor particles, n3 is a refractive index of the first filler particles, and n4 is a refractive index of the surface coating layers.

Abstract: Provided is a wavelength conversion member having excellent heat dissipation properties. A wavelength conversion member according to the present disclosure includes wavelength conversion particles each including a fluorescent substance and a first matrix surrounding the fluorescent substance; and a second matrix having a thermal conductivity higher than a thermal conductivity of the first matrix and surrounding the wavelength conversion particles. The fluorescent substance is, for example, at least one selected from the group consisting of a fluorescent substance containing a quantum dot, a fluorescent substance containing a metal complex, and an organic fluorescent substance. The first matrix includes, for example, at least one selected from the group consisting of a resin and glass. The second matrix includes, for example, an inorganic crystal. The inorganic crystal is, for example, a zinc oxide crystal.

Abstract: A wavelength conversion member of the present disclosure includes a first matrix, phosphor particles embedded in the first matrix, and at least one selected from the group consisting of first filler particles embedded in the first matrix and surface coating layers respectively covering surfaces of the phosphor particles. The wavelength conversion member satisfies at least one relationship selected from the group consisting of |n3?n1|>|n1?n2| and |n4?n1|>|n1?n2| wherein n1 is a refractive index of the first matrix, n2 is a refractive index of the phosphor particles, n3 is a refractive index of the first filler particles, and n4 is a refractive index of the surface coating layers.

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 includes, as a main component, a compound represented by a general formula (3-a)YO3/2.aCeO3/2.(5-b)AlO3/2.bGaO3/2.cKO1/2.dPO5/2, where a, b, c and d satisfy 0.12?a?0.18, 1.50?b?3.00, 0.01?c?0.08, and 0.01?d?0.08.

Abstract: A wavelength conversion member comprises: a substrate; and a wavelength conversion layer. The wavelength conversion layer contains a first phosphor and a second phosphor. The second phosphor has a higher thermal conductivity than the first phosphor. In the wavelength conversion layer, a volume of the second phosphor is larger than a volume of the first phosphor. The wavelength conversion layer includes a first portion and a second portion. The first portion is located closer to the substrate than the second portion, and is in direct contact with the second portion. Thicknesses of the first portion and the second portion are equal to each other. A volume V11 of the first phosphor in the first portion, a volume V12 of the second phosphor in the first portion, a volume V21 of the first phosphor in the second portion, and a volume V22 of the second phosphor in the second portion satisfy V11/V12<V21/V22.