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 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 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 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 includes a semiconductor light emitting device; and a wavelength converter. The wavelength converter includes: a substrate; a phosphor layer disposed on the substrate; and a light reflective layer disposed on the substrate so as to surround the phosphor layer. The phosphor layer includes phosphor particles and a first matrix material in which the phosphor particles are dispersed. The light reflective layer includes inorganic compound particles and a second matrix material in which the inorganic compound particles are dispersed. The inorganic compound particles have a refractive index higher than that of the first matrix material. The first matrix material has a refractive index higher than that of the phosphor particles. The phosphor particles have a refractive index higher than that of the second matrix material.

Abstract: A wavelength conversion member, comprises: a substrate; a first wavelength conversion layer on the substrate, the first wavelength conversion layer containing a first phosphor and a first matrix; and a second wavelength conversion layer containing a second phosphor, first inorganic particles, and a second matrix. The first phosphor and the second phosphor convert at least part of the excitation light incident on the second main surface into first light having longer wavelengths than the excitation light. The first light is emitted from the second main surface of the second wavelength conversion layer. A volume Vp1 of the first phosphor, a volume Vw1 of the first wavelength conversion layer, a volume Vp2 of the second phosphor, and a volume Vw2 of the second wavelength conversion layer satisfy Vp1/Vw1>Vp2/Vw2.

Abstract: A wavelength converter comprises: phosphor particles; and a matrix that is located between the phosphor particles and comprises zinc oxide crystallites. Pores are included in at least one of the zinc oxide crystallites.

Abstract: A wavelength conversion member, comprises: a substrate; a first wavelength conversion layer on the substrate, the first wavelength conversion layer containing a first phosphor and a first matrix; and a second wavelength conversion layer containing a second phosphor, first inorganic particles, and a second matrix. The first phosphor and the second phosphor convert at least part of the excitation light incident on the second main surface into first light having longer wavelengths than the excitation light. The first light is emitted from the second main surface of the second wavelength conversion layer. A volume Vp1 of the first phosphor, a volume Vw1 of the first wavelength conversion layer, a volume Vp2 of the second phosphor, and a volume Vw2 of the second wavelength conversion layer satisfy Vp1/Vw1>Vp2/Vw2.

Abstract: A light source includes a semiconductor light emitting device; and a wavelength converter. The wavelength converter includes: a substrate; a phosphor layer disposed on the substrate; and a light reflective layer disposed on the substrate so as to surround the phosphor layer. The phosphor layer includes phosphor particles and a first matrix material in which the phosphor particles are dispersed. The light reflective layer includes inorganic compound particles and a second matrix material in which the inorganic compound particles are dispersed. The inorganic compound particles have a refractive index higher than that of the first matrix material. The first matrix material has a refractive index higher than that of the phosphor particles. The phosphor particles have a refractive index higher than that of the second matrix material.

Abstract: A hydrogen gas inspection method includes: converting first light having a first wavelength to second light having a second wavelength longer than the first wavelength by using a phosphor, the first light being emitted from a semiconductor light emitting device; irradiating a space to be inspected with the second light; and determining whether hydrogen gas is present in the space utilizing Raman scattered light generated by the hydrogen gas irradiated with the second light.

Abstract: A wavelength converter comprises: phosphor particles; and a matrix that is located between the phosphor particles and comprises zinc oxide crystallites. Pores are included in at least one of the zinc oxide crystallites.

Abstract: A phosphor layer of a plasma display panel has a green phosphor layer containing Zn2SiO4:Mn particles. The Zn2SiO4:Mn particles satisfy requirements of Zn3p/Si2p?2.06 (1), and Zn2p/Si2p?1.23 (2) wherein Zn3p represents an emission amount of photoelectrons emitted from a 3p orbit of a Zn element in a region up to 10 nm from surfaces of the particles, Zn2p represents an emission amount of photoelectrons emitted from a 2p orbit of the Zn element in a region up to 3 nm from the surfaces of the particles, and Si2p represents an emission amount of photoelectrons emitted from a 2p orbit of a Si element in the region up to 10 nm from the surfaces of the particles.

Abstract: A phosphor layer of a plasma display panel has a green phosphor layer containing Zn2SiO4:Mn particles and (Y1-x, Gdx)3(Al1-y, Gay)5O12:Ce particles. The Zn2SiO4:Mn particles satisfy requirements of Zn3p/Si2p?2.10 (1), and Zn2p/Si2p?1.25 (2) wherein Zn3p represents an emission amount of photoelectrons emitted from a 3p orbit of a Zn element in a region up to 10 nm from surfaces of the particles, Zn2p represents an emission amount of photoelectrons emitted from a 2p orbit of the Zn element in a region up to 3 nm from the surfaces of the particles, and Si2p represents an emission amount of photoelectrons emitted from a 2p orbit of a Si element in the region up to 10 nm from the surfaces of the particles.

Abstract: The present invention provides a plasma display device that has light emission properties with short persistence where green light has a persistence time of 3.5 msec or less, that is excellent in luminance, luminance degradation resistance, and color tone, and that is suitable for, for example, a stereoscopic image display device.

Abstract: A protective layer of a plasma display panel includes a base layer formed on a dielectric layer, and a plurality of aggregated particles dispersed on an entire surface of the base layer. Phosphor layers include a green phosphor layer containing an Mn2+ activated short persistent green phosphor whose 1/10 afterglow time exceeds 2 msec and stays below 5 msec, and a Ce3+ activated green phosphor or an Eu2+ activated green phosphor having a luminescence peak in a wavelength region of at least 490 nm to less than 560 nm.