| abstract |
The present invention provides a fluorescent substance excellent both in quantum efficiency and in temperature characteristics, and also provides a light-emitting device utilizing the fluorescent substance. This fluorescent substance contains an inorganic compound comprising a metal element M, a trivalent element M 1 other than the metal element M, a tetravalent element M 2 other than the metal element M, and either or both of O and N. In the inorganic compound, the metal element M is partly replaced with a luminescence center element R. The crystal structure of the fluorescent substance is basically the same as Sr 3 Al 3 Si 13 O 2 N 21 , but the chemical bond lengths of M 1 -N and M 2 -N are within the range of ±15% based on those of Al—N and Si—N calculated from the lattice constants and atomic coordinates of Sr 3 Al 3 Si 13 O 2 N 21 , respectively. The fluorescent substance emits luminescence having a peak in the range of 490 to 580 nm when excited with light of 250 to 500 nm. |