Abstract
Glass ceramic phosphor materials containing a single phase of Ce: YAG micro-crystals were developed from homogeneous glasses in the pseudo-ternary Y2O3-Al2O3-SiO2 system. The glass ceramics show efficient yellow fluorescence due to the Ce3+: 5dà4f transition by 460nm excitation. Backward excitation of the GC plate with a blue LED gives white emission, which is binary complementary. From the analyses of the EL measurement data with an integrating sphere of 10-inch diameter, it was revealed that the composite of the GC and a blue LED chip gives high luminous efficiency comparable to that of commercial white LEDs working by the same current power.
