abstract |
One aspect of the present invention is a phosphor powder composed of Eu-containing α-sialon phosphor particles. For this phosphor powder, when the internal quantum efficiency after being kept at 600°C for 1 hour in the atmosphere is P1, and the internal quantum efficiency after being kept at 700°C for 1 hour in the atmosphere is P2, P1 is 70 % or more, and (P1-P2)/P1×100 is 2.8% or less. |