abstract |
An illumination system, comprising a radiation source and a luminescent material comprising a phosphor capable of absorbing a part of light emitted by the radiation source and emitting light of a wavelength different from that of the absorbed light; wherein said phosphor is a europium-activated oxonitridoalumosilicate of general formula AE 1−y−z Ln y Si 3 -xAl x−a B a O 1+x−y N 4−x+y :Eu z , wherein AE is an alkaline earth metal selected from the group of Sr, Ca, Ba, Mg and Zn; Ln is a lanthanide metal selected from the group of La, Ce, Pr, Nd, Sm, Gd, Tb, Dy, Ho, Er, Tm, Yb, Lu, and Y; B is a trivalent metal selected from the group of boron, gallium and scandium and a 0≦a<2, 0≦x<2, 0≦y≦1, 0.001<z≦0.1 provides white or colored illumination with high efficacy. The invention also relates to a luminescent material comprising a phosphor capable of absorbing a part of light emitted by the radiation source and emitting light of a wavelength different from that of the absorbed light; wherein said phosphor is a europium-activated oxonitridoalumosilicate of general formula AE 1−y−z Ln y Si 3−x Al x−a B a O 1+x−y N 4−x+y : Euz, wherein AE is an alkaline earth metal selected from the group of Sr, Ca, Ba, Mg and Zn; Ln is a lanthanide metal selected from the group of La, Ce, Pr, Nd, Sm, Gd, Tb, Dy, Ho, Er, Tm, Yb, Lu, and Y; B is a trivalent metal selected from the group of boron, gallium and scandium and 0≦a<2, 0≦x<2, 0≦y≦1. 0.001<z≦0.1. |