| 摘要 |
A long persistence, orange-red emitting phosphor has the formula AS:EumTrnOxXy wherein A is an alkaline earth metal ion, Tr is one or more trivalent rare earth metal ions, X is a halide, m is an integer in the range 0.01 to 0.5 atomic percent, n is an integer in the range 0.3 to 0.5 atomic percent, x is an integer in the range 0.01 to 2.0 atomic percent, and y is an integer in the range 0.01 to 0.5 atomic percent. These phosphors are made by reacting an alkaline earth metal sulfate to form the corresponding sulfide, mixing with europium oxide and one or more trivalent rare earth metal oxides to dope the sulfate, mixing the doped alkaline earth metal sulfate with a hydrocarbon and powdered sulfur, heating to form the corresponding phosphor sulfide and mixing with a halide compound to form the corresponding oxyhalide sulfide phosphor. The persistence time of the phosphors can be improved by grinding the phosphor and refiring it in the presence of an ammonium halide. |
