Patent number: 6753099
Abstract: The present invention provides a green emitting phosphor which includes an excess of the ordinary SiO2 component included in parent material Y2−2xSiO5 activated by Tb in terms of stoichiometric ratio. The composition of the above phosphor is represented by chemical formula:
where values of x, y, z, a, and b are assigned, subject to 0<x≦1, 0≦y≦1, 0≦z≦1, 0<a≦1, and 0≦b≦1, and M is at least one element selected from a group comprising Sc, In, La, Lu, Yb, Ce, Eu, Sm, Tm, Ho, Er, and Nd. By using this phosphor, phosphors that emit light of higher luminance with less luminance degradation and are suitable for high-quality image display and imaging devices producing high-quality images are obtained.
June 27, 2002
Date of Patent:
June 22, 2004
Hitachi, Ltd., Hitachi Device Engineering Co., Ltd., Kasei Optonix, Ltd.
Shin Imamura, Masatoshi Shiiki, Masaaki Komatsu, Hidetsugu Matsukiyo, Yoshihiro Koseki, Takashi Hase, Tsutomu Yamada