| abstract |
Disclosed is a group of green-light-emitting bivalent europium-activated oxynitride phosphor particles each of which is a ss-type SiAlON substantially represented by the general formula: EuaSibAlcOdNe [wherein a, b, c, d and e are numbers that meet the requirements represented by the following formulae: 0.005=a=0.4, b+c=12 and d+e=16], wherein the phosphor particles having a value produced by dividing the longer particle diameter by the shorter particle diameter of greater than 1.0 and not greater than 3.0 (1) constitute 60% or more of the whole phosphor particles. Also disclosed is a high-efficiency and stable light-emitting device utilizing a ss-type SiAlON, which utilizes the group of the phosphor particles in a wavelength-converting unit thereof. Further disclosed is a group of phosphor particles for use in the device. |