A light emitting diode (LED) assembly includes an LED light source having a first light output with a characteristic spectrum and at least one phosphor through which the first light output passes. The phosphor includes the quaternary compound M-Li—Al—O, where M is Ba, Sr, or Ca, activated by Eu.sup.2+ or Ce.sup.3+.

An object is to provide a new type of near-infrared ray-emitting phosphor which exhibits excellent emission intensity. A near-infrared ray-emitting phosphor is represented by a general formula, (Y,Lu,Gd).sub.3-x-y (Ga,Al,Sc).sub.5O.sub.12:(Cr.sub.x,(Yb,Nd).sub.y) (0.05<x<0.3, 0≤y<0.3).

A light emitting device includes a light emitting element having a peak emission wavelength of 410 nm to 440 nm 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.

An -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 -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 -sialon phosphor and a semiconductor light-emitting element capable of exciting the -sialon phosphor.

A phosphor and a light source device having the phosphor having a high internal quantum yield by enabling a large Ce amount, capable of shifting the fluorescence wavelength of yellow fluorescence to the long wavelength side, having satisfactory heat quenching resistance, and excellent in blue light transmittance. The phosphor includes a Ce:YAG single crystal having a Ce amount of 0.7 parts by mole or more when the total amount of Y and Ce is 100 parts by mole.

A light source device includes a solid-state light source, a dichroic mirror, a first condensing element, a fluorescent plate, a second condensing element, a retardation plate, and a reflection plate. The dichroic mirror separates light from the solid-state light source into first light and second light, and combines blue light and light containing green and red components, the blue light being obtained by converting polarization of the second light, the light containing green and red components being obtained by converting a wavelength of the first light. The first condensing element condenses the first light separated by the dichroic mirror. The fluorescent plate converts the wavelength of the first light condensed by the first condensing element. The second condensing element condenses the second light separated by the dichroic mirror. The retardation plate converts polarization of the second light condensed by the second condensing element.

A phosphor and a method for making the phosphor are disclosed. In an embodiment a phosphor for emission of red light includes Sr.sub.xCa.sub.1xAlSiN.sub.3:Eu, wherein x is: 0.8<x1, wherein between 0.1% and 5% inclusive of the Sr, Ca and/or Sr/Ca lattice sites are replaced by Eu, wherein, in a x-ray structure analysis, the phosphor in orthorhombic description exhibits a reflection (R) having Miller indices 1 2 1, wherein the phosphor has a structure including (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.

A phosphor and a lighting device are disclosed. In an embodiment a lighting device includes a first phosphor disposed in a beam path of the primary radiation source, wherein the first phosphor has the formula Sr(Sr.sub.aM.sub.1a)Si.sub.2Al.sub.2(N,X).sub.6:D,A,B,E,G,L, wherein element M is selected from Ca, Ba, Mg or combinations thereof, wherein element D is one or more elements selected from Mn, Ce, Pr, Nd, Sm, Eu, Tb, Dy, Ho, Er, Tm, alkali metals or Yb, wherein element A is selected from divalent metals different than those of the elements M and D, wherein element B is selected from trivalent metals, wherein element E is selected from monovalent metals, wherein element G is selected from tetravalent elements, wherein element L is selected from trivalent elements, wherein element X is selected from O or halogen, and wherein a parameter a is between 0.6 and 1.0.

A light emitting device includes a light emitting element having a peak emission wavelength of 410 nm to 440 nm 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.