Phosphor and LEDs containing same
View Patent ↗There is herein described a phosphor for use in LED applications and particularly in phosphor-conversion LEDs (pc-LEDs). The phosphor has a composition represented by (Y 1-x Ce x ) 3 (Al 1-y Sc y ) 5 O 12 wherein 0<x≦0.04 and 0<y≦0.6 and can be as applied to an LED as a transparent sintered ceramic or used in a powder form. By adjusting the composition of the phosphor, the phosphor can be made to emit light in the green to yellow regions of the visible spectrum upon excitation by a blue-emitting InGaN LED.
1. A phosphor having a composition represented by (Y 1-x Ce x ) 3 (Al 1-y Sc y ) 5 O 12 wherein 0<x≦0.002 and 0.2<y≦0.6.
2. The phosphor of claim 1 wherein the phosphor when excited emits light having color coordinates Cx and Cy wherein C x is in a range from about 0.35 to about 0.44 and C y is in a range from about 0.55 to about 0.58.
3. A phosphor-conversion LED comprising: an LED that emits a blue light and a phosphor for converting at least a portion of the blue light into light of a different wavelength, the phosphor having a composition represented by (Y 1-x Ce x ) 3 (Al 1-y Sc y ) 5 O 12 wherein 0<x≦0.002 and 0.2≦y≦0.6.
4. The phosphor-conversion LED of claim 3 wherein the blue light has a wavelength from about 420 nm to about 490 nm.
5. The phosphor-conversion LED of claim 3 wherein the phosphor when excited by the blue light by emitted by the LED emits light having color coordinates Cx and Cy wherein C x is in a range from about 0.35 to about 0.44 and C y is in a range from about 0.55 to about 0.58.
6. The phosphor-conversion LED of claim 5 wherein the blue light has a wavelength from about 420 nm to about 490 nm.