摘要 |
Novel phosphor systems are disclosed having the formula A<SUB>2</SUB>SiO<SUB>4</SUB>:Eu<SUP>2+</SUP>D, where A is at least one of a divalent metal selected from the group consisting of Sr, Ca, Ba, Mg, Zn, and Cd; and D is a dopant selected from the group consisting of F, Cl, Br, I, S and N. In one embodiment, the novel phosphor has the formula (Sr<SUB>1-x-y</SUB>Ba<SUB>x</SUB>M<SUB>y</SUB>)<SUB>2</SUB>SiO<SUB>4</SUB>: Eu<SUP>2+</SUP>F (where M is one of Ca, Mg, Zn, or Cd in an amount ranging from 0<y<0.5). The phosphor is configured to absorb visible light from a blue LED, and luminescent light from the phosphor plus light from the blue LED may be combined to form white light. The novel phosphors can emit light at intensities greater than either conventionally known YAG compounds, or silicate-based phosphors that do not contain the inventive dopant ion.
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