A light emitting device includes a light emitting element having a peak emission wavelength of 410 nm to 440nm and a phosphor member. The phosphor member includes a first phosphor having a peak emission wavelength of 430 nm to 500 nm and containing an alkaline-earth phosphate, a second phosphor having a peak emission wavelength of 440 nm to 550 nm and containing at least one of an alkaline-earth aluminate and a silicate containing Ca, Mg, and Cl, a third phosphor having a peak emission wavelength of 500 nm to 600 nm and containing a rare-earth aluminate, a fourth phosphor having a peak emission wavelength of 610 nm to 650 nm and containing a silicon nitride containing Al and at least one of Sr and Ca, and a fifth phosphor having a peak emission wavelength of 650 nm to 670 nm and containing a fluorogermanate.

A method for producing a photo-luminescent material, including the following steps: (1) producing, according to a sol-gel method, a sol and then a gel of first precursors of a first substance from the sol; (2) crushing the gel; (3) optionally, annealing the gel in order to form first particles of the first substance of which the average size is between 1 pm and 20 um; (4) producing a colloidal dispersion of second particles of a second substance, different from the first substance or identical to the first substance, of which the average size is between 5 nm and 400 nm; (5) mixing the colloidal dispersion with the sol in step (1) before forming the gel or with the first particles after step (3); and (6) annealing the mixture obtained in step (5), resulting in an increase in the compactness of the mixture, the average size of the second particles after annealing being between 100 nm and 900 nm. A photo-luminescent material including a mixture of first particles of a first photo-luminescent substance of which the average size is between 1 pm and 20 pm and second particles of a second photo-luminescent substance, different from the first photo-luminescent substance or identical to the first photo-luminescent substance, of which the average size is between 100 nm and 900 nm.

The present invention relates to a phosphor plate including a sintered body including (Y.sub.1-x-y, Gd.sub.x, Ce.sub.y).sub.3Al.sub.5O.sub.12 particles and Al.sub.2O.sub.3 particles, in which 0.07≤×≤0.11 and 0.010 ≤y≤0.015 are satisfied, the (Y.sub.1-x-y, Gd.sub.x, Ce.sub.y).sub.3Al.sub.5O.sub.12 particles in the sintered body has an average particle diameter of 4 μm or more and 6 μm or less, the (Y.sub.1-x-y, Gd.sub.x, Ce.sub.y).sub.3Al.sub.5O.sub.12 particles has a concentration of 20 vol % or more and 30 vol % or less with respect to a total amount 100 vol % of the (Y.sub.1-x-y, Gd.sub.x, Ce.sub.y).sub.3Al.sub.5O.sub.12 particles and the Al.sub.2O.sub.3 particles, a ratio of an average particle diameter of the Al.sub.2O.sub.3 particles to the average particle diameter of the (Y.sub.1-x-y, Gd.sub.x, Ce.sub.y).sub.3Al.sub.5O.sub.12 particles is 1 or more and 2 or less, and the sintered body has a total thickness of 150 μm or more and 250 μm or less.

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.

Provided is a phosphor in which a first phase and a second phase are three-dimensionally entangled with each other. The phosphor further includes a third phase different from the first phase and the second phase, in a cross-sectional visual field in a predetermined range, an area ratio of the third phase in the phosphor is 0.5% to 3.0%, and at least a part of the third phase is a bridging third phase existing at a position where a part of the first phase and another part of the first phase are bridged.

Provided is a method for producing a crystal body that can obtain a crystal body having a relatively large size and a more uniform composition, and a novel single crystalline phosphor obtained by the above producing method. The single crystalline phosphor contains YAG or LuAG as a main component and at least one element of Ce, Pr, Sm, Eu, Tb, Dy, Tm, and Yb as an accessory component. In a cross section of the single crystalline phosphor, a uniform concentration region in which the accessory component is uniformly distributed is located in a central portion of the cross section, and an area ratio of the uniform concentration region to a cross-sectional area of the cross section is 35% or more.

A white light emitting device, a light bar and a light apparatus. A relative spectrum of the white light emitting device is ϕ(λ). A relative spectrum of a black body radiation with a corresponding color temperature is S(λ). An area normalization is performed on φ(λ) and S(λ) to convert an equal energy spectrum φ′(λ) of the white light emitting device and an equal energy spectrum S′(λ) of the black body radiation with the corresponding color temperature. A degree of similarity R of the equal energy spectrum of the white light emitting device and the equal energy spectrum of the black body radiation satisfies the following formula:

[00001]$R=1-\frac{{\Sigma }_{\lambda i}^{\lambda n}.Math.S^{\prime }\left(\lambda \right)-{\Phi }^{\prime }\left(\lambda \right).Math.}{{\Sigma }_{\lambda i}^{\lambda n}{S}^{\prime }\left(\lambda \right)},$

when λi is 380 nm, λn is 680 nm, R≥85%.

A phosphor and a method for making the phosphor are disclosed. In an embodiment a phosphor for emission of red light includes Sr(Sr.sub.aCa.sub.1-a)Si.sub.2Al.sub.2N.sub.6:Eu, wherein x is 0.8<x≤1, wherein between 0.1% and 5% inclusive of the Sr, Ca and/or Sr/Ca lattice sites are replaced by Eu, wherein the parameter value a is between 0.6 and 1.0 inclusive, wherein the phosphor has a structure comprising (Si/Al)N.sub.4 tetrahedra arranged in a 3D network, in which layers in an a-c plane are linked in a b-direction, and wherein pure Sr positions and positions having a mixed Sr/Ca population are intercalated between the network, layer by layer.

An α-sialon phosphor represented by general formula: M.sub.xEu.sub.y(Si,Al).sub.12(O,N).sub.16, where M represents at least one or more elements selected from Li, Mg, Ca, Y and a lanthanoid (excluding La and Ce), 0<x, and 0<y, where the phosphor includes, as a host crystal, a crystal structure identical to that of an α-sialon crystal phase, and the phosphor has a bulk density of 1.00 g/cm.sup.3 or more and 1.80 g/cm.sup.3 or less. Also provided is a light-emitting element including the α-sialon phosphor and a semiconductor light-emitting element capable of exciting the α-sialon phosphor.

The present invention relates to a sulfide phosphor including a parent body containing one or more selected from Ba, Li, and S, and Al and Ga as constituent elements, wherein one or more activators selected from Eu and Ce are employed to the parent body.