Patent ID: 7498736

Claim:
A luminescent material comprising: a compound having composition represented by following general formula (A) (Sr a1 , Ba b1 , Ca c1 , Tb v1 , Eu w1 ) 2 SiO 4 (A) wherein, a 1 , b 1 , c 1 , v 1 , and w 1 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≦0.05 (6).