Patent ID: 7892453

Claim:
A phosphor composition comprising, as a main component of a phosphor host, a nitride represented by any of a composition formula of MAlSiN 3 . a′Si 3 N 4 , MAlSiN 3 .a′M 2 Si 5 N 8 , MAlSiN 3 .a′MSiN 2 , and MAlSiN 3 .a′MSi 7 N 10 and comprising a metal ion selected from rare-earth ions and transition metal ions as a luminescent center ion, wherein M is at least one element selected from the group consisting of Mg, Ca, Sr, Ba, and Zn, and a′ is a numerical value satisfying 0.25 <a′<1, and the phosphor composition optionally contains a metal element in an amount corresponding to less than 10 atomic% with respect to at least one of the elements M, Al, and Si and optionally contains oxygen in an amount corresponding to less than 10 atomic% with respect to the element N.