Patent ID: 7005197
Filing Date: 2006-02-28
Classification: C09K,G02F,H01L,Y02B,Y10S

Abstract:
1. A light source provided with an ultraviolet visible excitation light generation unit that generates first visible light and ultraviolet light and a fluorescence generation unit having a phosphor screen that generates second visible light when ultraviolet visible light generated from the ultraviolet visible excitation light generation unit irradiates the phosphor screen as excitation light for acquiring white light by mixing the first visible light from the ultraviolet visible excitation light generation unit and the second visible light from the fluorescence generation unit, wherein: the phosphor screen includes phosphor expressed by the following composition formula, the phosphor composition formula: (L wherein, L is at least one type of rare-earth element selected from a group of La, Y, Lu and Sc, a, b and c are each in the following composition ranges of 0≦a<1.0, 0<b≦0.1 and 0≦c≦1.0, M is dopant of a monovalent metal element selected from a group consisting of Li, Na, K, Cu, Ag and Au and the content d is in a range of 0<d≦1000 wt-ppm.