| 摘要 |
A phosphor improved against luminance deterioration with time under vacuum ultraviolet irradiation, a phosphor paste composition, and a vacuum ultraviolet excitation light emitting element high in luminance retaining rate and improved in luminance, are presented. An alkaline earth aluminate phosphor which is a phosphor represented by the formula a (M<SUB>1-x</SUB>Eu<SUB>x</SUB>)O.6Al<SUB>2</SUB>O<SUB>3 </SUB>(wherein M represents at least one alkaline earth metal element selected from the group consisting of Ba, Sr and Ca, and x and a satisfy 0<x<1 and O.9<=a<=1.8, respectively) and which has a wide-band peak over an angle region of diffraction angle (2theta) of from 28° to 31° in powder diffraction X-ray spectrum by CuKalpha1 characteristics X-ray, and a vacuum ultraviolet excitation light emitting element provided with a fluorescent layer made of the phosphor. |
