Phosphor, process for producing the same, and luminescent device

Abstract

A green phosphor for emitting light, a spectrum of which is sharp, in an ultraviolet and visible light region, which has higher green light brightness than the conventional rare earth-activated sialon phosphor and has higher durability than the conventional oxide phosphor, is provided. The phosphor being characterized in that Al and a metal element M (here, M is Eu) are incorporated into a crystal of a nitride or oxynitride having a β-type Si3N4 crystal structure as a solid solution, the content of oxygen in the crystal does not exceed 0.8% by mass, and the phosphor emits a visible light having a luminescence peak wavelength in the range of 450 nm to 650 nm upon exposure to an excitation source is provided. This luminescence spectrum has a sharp spectrum shape. Further, a manufacturing method of the phosphor, a lighting device and an image display device utilizing the phosphor are also provided.

Dependencies are inferred from the claim text.