abstract |
A fluorophor includes: α-type sialon crystal which is expressed by a general formula: (Li x1 , Eu x2 )(Si 12−(m+n) Al m+n )(O n N 16−n ), wherein x1 is an amount of solid solution of Li in a sialon unit cell, and x2 is an amount of solid solution of Eu in the sialon unit cell, wherein the parameters x1, x2, m, and n satisfy: 1.6≦x1≦2.4 (1), 0.001≦x2≦0.4 (2), 1.8≦m≦2.4 (3), 0.8≦n≦1.2 (4), wherein the α-type sialon crystal emits fluorescence with a peak in a wavelength region of from 550 nm to 575 nm upon irradiation of an excitation source. |