Patent ID: 8062550

Claim:
A luminescent material comprising: a compound having a composition represented by a following general formula (A): (Sr a1 ,Ba b1 ,Ca c1 ,Re v1 ,Eu w1 ) 2 SiO 4 (A) wherein, Re is at least one selected from a group consisting of Pr and Dy; and a1, b1, c1, v1, and w1 satisfy following relationships: a 1+ b 1+ c 1+ v 1+ w 1=1 (1); 0≦ a 1/(1− v 1− w 1)≦1 (2); 0≦ b 1/(1− v 1− w 1)≦1 (3); 0≦ c 1/(1− v 1− w 1)≦1 (4); 0< v 1≦0.15 (5); 0< w 1≦0.02 (6); and v 1/ w 1>1 (7), wherein the luminescent material is excited by light having a main luminescence peak falling within a wavelength ranging from 310 nm to 420 nm and the luminescent material exhibits a narrowband light emitting spectrum and a broadband light emitting spectrum and a peak wavelength of the luminescent material is in the range of 500-580 nm.