Patent ID: 7649309
Filing Date: 2010-01-19
Classification: C09K,H01J,H01L

Abstract:
1. A light source having a primary radiation source, which emits radiation in the short-wave region of the optical spectral region in the wavelength range from 140 to 480 nm, this radiation being partly or completely converted into secondary radiation with a longer wavelength in the visible spectral region by means of at least one first phosphor; wherein the first phosphor is a highly efficient, stable oxynitride phosphor from the class of the oxynitridosilicates with a cation M and the empirical formula Msi 2 O 2 N 2 ; M simultaneously comprises as constituent Sr and Ca and also an activator D; D includes at least divalent europium; M=Sr 1-x-y Ca y Eu x where 0.3≦x+y≦0.725, with a Ca/Eu ratio of >1; and the first phosphor has an emission with a dominant wavelength in the range from 555 to 568 nm.