| abstract |
Spherical particles of a rare earth activated barium fluoride halide phosphor precursor having the formula(I):[in which M<II >is Ca or Sr; M<I >is Li, Na, K, Rb or Cs; X is Cl, Br or I; Ln is a rare earth element; and a, y and z are numbers satisfying the conditions of 0<=a<=0.5, 0<=y<=0.05, and 0<z<=0.2] are favorably employable for preparing spherical rare earth activated barium fluoride halide phosphor particles. |