Fluorescent substance, method for manufacturing the same, illuminator and image display device

摘要

The invention provides a green fluorescent substance being higher in luminance of green than a conventional rare-earth activated sialon fluorescent substance and more excellent in durability than a conventional oxide fluorescent substance. The inventors have succeeded in acquiring a fluorescent substance which is obtained by solid-dissolving Eu into a nitride or oxy-nitride crystal having a beta-type Si₃N₄ crystal structure and emits a fluorescent light having a peak within a range of 500 nm to 600 nm in wavelength by being irradiated with an excitation source.