Patent ID: 7253446
Filing Date: 2007-08-07
Classification: C04B,C09K,H01L

Abstract:
1. A light-emitting device comprising: a semiconductor light-emitting element that emits blue-violet or blue light; and a fluorescent material that absorbs all or a part of the blue-violet or blue light emitted by the semiconductor light-emitting element and emits fluorescence of wavelengths different from that of the blue-violet or blue light, wherein the fluorescent material comprises a mixture of a first fluorescent material that emits green or yellow-green light, a second fluorescent material that has a longer emission wavelength than that of the first fluorescent material and emits yellow-green, yellow, or yellow-red light, and a third fluorescent material that has a longer emission wavelength than the second fluorescent material and emits yellow-red or red light, and the first fluorescent material is a europium-activated β-SiAlON fluorescent material, the second fluorescent material is a europium-activated α-SiAlON fluorescent material, and the third fluorescent material is a nitride crystalline red fluorescent material expressed by a general formula of (Ca,Eu)AlSiN