| abstract |
The present invention aims at providing a chemically stabilized inorganic phosphor, among oxynitride phosphors including alkaline earths, which oxynitride phosphor emits orange or red light at longer wavelengths at higher luminance than conventional sialon phosphors activated by rare earths. The present invention further aims at providing a light emitting instrument based on the phosphor, for a lighting instrument excellent in color rendering property and for an image displaying apparatus excellent in durability. n The solving means resides in provision of a fundamental phosphor comprising: n a composition on a pseudo-ternary phase diagram including AO (A is one kind or two or more kinds of element(s) selected from Mg, Ca, Sr, and Ba; and AO is oxide of A), Si 3 N 4 , and SiO 2 as end members, respectively, and satisfying all of the following conditions: n in a composition formula, pAO-qSi 3 N 4 -rSiO 2 (p+q+r=1),n n0.1≦p≦0.95 (1),n n0.05≦q≦0.9 (2), andn n0≦r≦0.5 (3), andn n at least a metallic element M (M is one kind or two or more kinds of element(s) selected from Mn, Ce, Nd, Sm, Eu, Tb, Dy, Ho, Er, Tm, and Yb) dissolved, in a solid state, in the composition. |