| abstract |
The present invention provides an oxynitride phosphor powder having an external quantum efficiency higher than that of the conventional oxynitride phosphor powder having a fluorescent peak wavelength of 610 to 625 nm. The oxynitride phosphor powder of the present invention has a composition formula of Ca x 1 Eu x 2 Si 12 - (y + z) Al (y + z) O z N 16 -z wherein x1, x2, y, ? S1 + x2? 2.90, 0.18? X2 / x1? 0.70, 4.0? Y? 6.5, 0.0? Z? 1.0). It is preferable that Li further contain 50 to 10000 ppm. The content of aluminum nitride is preferably larger than 0 mass% and smaller than 33 mass%. |