An oxynitride orange-red fluorescent substance and a light-emitting film or sheet and a light-emitting device comprising the same are disclosed. The chemical formula of the oxynitride orange-red fluorescent substance is M.sub.mA.sub.aSi.sub.xN.sub.yO.sub.z:dR in which the element M is one or more of the elements selected from Ca, Sr and Ba, the element A is Al or a mixture of Al with one or more of the elements selected from Ga, La, Sc and Y, the element R is one or more of the elements selected from Ce, Eu and Mn, 0.8m1.2, 1<a<1.7, 1<x<1.7, 3<y<4.2, 0<z<0.7, and 0.001d0.2.

Provided is a chemically and thermally stable phosphor having different light-emitting characteristics than a conventional phosphor and having high light-emitting intensity even when combined with an LED of 410 nm or lower. The phosphor comprises an inorganic compound in which an inorganic crystal including A element, D element, X element (A is one or more elements selected from Mg, Ca, Sr, and Ba; D is one or more elements selected from Si, Ge, Sn, Ti, Zr, and Hf; and X is one or more elements selected from O, N, and F), and, if necessary, E element (where E is one or more elements selected from B, Al, Ga, In, Sc, Y, and La) includes Li element and M element (where M is one or more elements selected from Mn, Ce, Pr, Nd, Sm, Eu, Tb, Dy, and Yb).

The present invention relates to compounds of formula I,

M.sup.IM.sup.II.sub.3 M.sup.III.sub.3M.sup.IV.sub.3N.sub.2O.sub.12:EuI

wherein, M.sup.I, M.sup.II, M.sup.III, and M.sup.IV have one of the meanings as given in claim 1, to a process of their preparation, the use of these compounds as conversion phosphors or in an emission-converting material, the use of these phosphors in electronic and electro optical devices, such as light emitting diodes (LEDs) and solar cells, and especially, to illumination units comprising at least one of these phosphors.

Provided are a transparent fluorescent sialon ceramic having fluorescence and optical transparency; and a method of producing the same. Such a transparent fluorescent sialon ceramic includes a sialon phosphor which contains a matrix formed of a silicon nitride compound represented by the formula M.sub.x(Si,Ai).sub.y(N,O).sub.z (here, M represents at least one selected from the group consisting of Li, alkaline earth metals, and rare earth metals, 0x/z<3, and 0<y/z<1) and a luminescent center element.

Provided are an oxynitride phosphor comprising a JEM crystal as a main component and being characterized by light-emitting properties (light emission color or excitation property, light emission spectrum) that is different from the known JEM phosphor, and an application thereof. The phosphor of the present invention comprises the JEM crystal activated with Eu and represented by MAl(Si, Al).sub.6(O, N).sub.10 (where the M element is one or more elements selected from the group consisting of Ca, Sr, Eu, La, Sc, Y, and lanthanoid elements; and includes at least Eu as well as Ca and/or Sr).

The invention relates to a white emitting light source with an improved luminescent material of the formula (AEN2/3)*b(MN)*c(SiN4/3)*d1CeO3/2*d2EuO*xSiO2*yAlO3/2 wherein AE is an alkaline earth metal chosen of the group of Ca, Mg, Sr and Ba or mixtures thereof and M is a trivalent element chosen of the group of Al, B, Ga, Sc with d1>10*d2. In combination with a UV to blue light generating device this material leads to an improved light quality and stability, especially an improved temperature stability for a wide range of applications.

To provide a phosphor being chemically-thermally stable and having high luminous intensity if combined with LED of not exceeding 470 nm. A phosphor of the present invention includes: inorganic compound including: a crystal represented by Li.sub.1Ba.sub.2Al.sub.1Si.sub.7N.sub.12; a crystal represented by (Li, A).sub.3(D, E).sub.8X.sub.12; and an inorganic crystal having the same crystal structure as the crystal represented by Li.sub.1Ba.sub.2Al.sub.1Si.sub.7N.sub.12; and a solid-solution crystal thereof, which contains Li, A, D, E, and X elements (A represents at least one selected from Mg, Ca, Sr, Ba, Sc, Y and La; D represents at least one selected from Si, Ge, Sn, Ti, Zr and Hf; E represents at least one selected from B, Al, Ga and In; and X represents at least one selected from O, N and F), wherein M element (M represents at least one selected from Mn, Ce, Pr, Nd, Sm, Eu, Tb, Dy and Yb) is solid-solved into each.