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 display device is providing and includes first substrate including first transparent substrate, and pixel electrode disposed in each of pixels on first transparent substrate; second substrate including second transparent substrate having first and second side surfaces, and common electrode disposed over pixels; and liquid crystal layer disposed between first and second substrates and including stripe-shaped polymer and liquid crystal molecules.

Abstract: A display device includes a liquid crystal layer between a first substrate and a second substrate. The first substrate includes a wiring line and a pixel electrode. The liquid crystal layer includes a stripe-shaped polymer extending in a first direction and a liquid crystal molecule. The liquid crystal layer includes a first polymer in an area overlapping the wiring line and a second polymer in an area overlapping the pixel electrode. The first polymer includes a first portion extending in a direction different from the first direction. The second polymer includes a second portion extending in a direction different from the first direction. A density of the first portion is higher than a density of the second portion.

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: 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 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.

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.

Abstract: An oxychloride phosphor of the present disclosure includes divalent Eu arranged as an augmenting agent, at part of locations. The locations correspond to site of at least two kinds of predetermined substances included in a host crystal. A rate of the number of the divalent Eu with respect to the sum of the number of moles of the predetermined substance and the number of moles of the divalent Eu is less than 2%. When the predetermined substance is represented by A, the oxychloride phosphor is represented by a general formula of xAO.yEuO.SiO2.zCl. In this formula, A represents Sr and Ca, or Sr, Ca, and Mg, y indicates a value of not less than 0.002 and not more than 0.02, x+y indicates a value of more than 1.00 and not more than 1.30, and z indicates a value of not less than 0.20 and not more than 0.70.

Abstract: A red phosphor material includes an essential component represented by a formula of A2-2xRxEuySmzLnx-y-zM2O8 as a main component, where A represents at least one selected from Ca and Sr; R represents at least one selected from Li, Na, and K; Ln represents at least one selected from La, Gd, and Y; M represents at least one selected from W and Mo; and x, y, and z are numerical values that satisfy 0.2?x?0.7, 0.2?y+z?0.6, 0.005?z?0.04, and x?y?z?0. A light-emitting device includes an excitation light source and the red phosphor material that absorbs excitation light emitted by the excitation light source and emits red light.

Abstract: A phosphor includes a host crystal including Sr3MgSi2O8 crystal and SrMgSiO4 crystal and also includes Eu2+, or Eu2+ and Mn2+ as luminescent centers. Alternatively, a phosphor includes a host crystal including Sr3MgSi2O8 crystal and SrMgSiO4 and also includes Eu2+ as a luminescent center, the phosphor being free from Mn2+ as a luminescent center. A light-emitting device includes a phosphor layer containing the phosphor. A projector and a vehicle include the light-emitting device.

Abstract: A red phosphor material comprising an essential component represented by a formula of ALn1-x-yEuxSmyM2O8 as a main component, where A represents at least one selected from Li, Na, and K; Ln represents at least one selected from La and Gd; M represents at least one selected from W and Mo; and x and y are numerical values that satisfy 0.1?x+y?0.7 and 0.005?y?0.08. A light-emitting device includes an excitation light source and the red phosphor material that absorbs excitation light emitted by the excitation light source and emits red light.

Abstract: The present invention provides an oxynitride silicate fluorescent substance capable of output a light having a high luminance even when irradiated by an exciting light having a high energy density. The present invention is a yellow fluorescent substance represented by a chemical formula (Ba1-x-y-z,Srx)aSibOcNd:Eu2+y,Y3+z (0.9?a?1.1, 1.9?b?2.1, 1.9?c?2.1, 1.9?d?2.1, 0?x?1, 0<y<0.01, and 0?z<0.01).

Abstract: A fluorescent material according to an aspect of the present disclosure mainly comprises a compound represented by AB0.5-w-x-y-zCwEuxSmyLnzW0.5O3. A is one or more elements selected from the group consisting of alkaline earth metals and mainly contains Ca. B is one or more elements selected from the group consisting of divalent metals and mainly contains Mg. C is one or more elements selected from the group consisting of alkali metals and mainly contains Li, Na, or Li and Na. Ln is one or more elements selected from the group consisting of rare earth elements excluding Eu and Sm. w, x, y, and z meet the following conditions: 0.05?w?0.25, 0.05?x+y?0.25, 0.0?y?0.02, and w=x+y+z.

Abstract: The present disclosure provides a (Ba1?z,Srz)3MgSi2O8:Eu2+ based phosphor with high emission quantum efficiency. Specifically, the present disclosure provides a blue light emitting phosphor including: a (Ba1?z,Srz)3MgSi2O8 based crystal where z satisfies 0?z<1 and a (Ba1?z,Srz)MgSiO4 based crystal where z satisfies 0?z<1 as a host crystal; and Eu2+ as a luminescent center.

Abstract: A fluorescent material according to an aspect of the present disclosure mainly comprises a compound represented by AB0.5-w-x-y-zCwEuxSmyLnzW0.5O3. A is one or more elements selected from the group consisting of alkaline earth metals and mainly contains Ca. B is one or more elements selected from the group consisting of divalent metals and mainly contains Mg. C is one or more elements selected from the group consisting of alkali metals and mainly contains Li, Na, or Li and Na. Ln is one or more elements selected from the group consisting of rare earth elements excluding Eu and Sm. w, x, y, and z meet the following conditions: 0.05?w?0.25, 0.05?x+y?0.25, 0.0?y?0.02, and w=x+y+z.

Abstract: A phosphor includes a host crystal including Sr3MgSi2O8 crystal and SrMgSiO4 crystal and also includes Eu2+, or Eu2+ and Mn2+ as luminescent centers. Alternatively, a phosphor includes a host crystal including Sr3MgSi2O8 crystal and SrMgSiO4 and also includes Eu2+ as a luminescent center, the phosphor being free from Mn2+ as a luminescent center. A light-emitting device includes a phosphor layer containing the phosphor. A projector and a vehicle include the light-emitting device.