Green emitting phosphor for use in UV light emitting diodes
AssigneeGeneral Electric Company
InventorsAlok M. Srivastava, William W. Beers, Holly A. Comanzo
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Abstract
A green-emitting phosphor is provided, which has the general formula LnxBO3: Ce3+y, Tb3+z, where Ln includes one or more lanthanide-type elements, such as Sc, Y, La, Gd, and Lu. x+y+z=1; 0≦x≦0.98; 0≦y≦0.5; and 0≦z≦0.5. The phosphor efficiently converts light in the UV/blue region of the spectrum (250-400 nm) to light of longer wavelength, with a peak emission intensity of about 545 nm. The phosphor is used alone, or in a phosphor blend for converting UV/blue light from a GaN-base light emitting diode to green or white light, respectively.
Claims19
A light source comprising:
- a light emitting component which emits light at a first wavelength;
- and
- a phosphor material positioned to receive the light emitted by the light emitting component, the phosphor material including a green-emitting phosphor which converts a portion of the light of the first wavelength to light of a second, longer wavelength, the green-emitting phosphor having the general formula LnxBO3:
- Ce3+y, Tb3+z, where:
- x=1−(y+z);
- 0<x≦0.98;
- 0.01≦y≦0.5;
- 0.02≦z≦0.5;
- and
- Ln includes one or more of Sc, Y, La, Gd, Lu, and other lanthanide elements.
A light source comprising:
- a housing, the housing being closed by a window;
- a light emitting component positioned within the housing which emits light at a first wavelength;
- and
- a phosphor material, the phosphor material being deposited on the window and positioned to receive the light emitted by the light emitting component, the phosphor material including a green-emitting phosphor which converts a portion of the light of the first wavelength to light of a second, longer wavelength, the green-emitting phosphor having the general formula LnxBO3:
- Ce3+y, Tb3+z, where:
- x=1−(y+z);
- 0<x≦0.98;
- 0.01≦y≦0.5;
- 0.02≦z≦0.5;
- and
- Ln includes one or more of Sc, Y, La, Gd, Lu, and other lanthanide elements.
A method of converting UV/blue light to light in the green region of the electromagnetic spectrum comprising:
- converting the UV/blue light with a phosphor of the general formula LnxBO3:
- Ce3+Y, Tb3+z where:
- Ln includes one or more of Sc, Y, La, Gd, Lu, and other lanthanide elements;
- x=1−(y+z);
- 0<x≦0.98;
- 0.01≦y≦0.5;
- and
- 0.01≦z≦0.5.
A phosphor material having the general formula LnxBO3:
- Ce3+y, Tb3+z where:
- Ln includes one or more of Sc, Y, La, Gd, Lu, and other lanthanide elements;
- x=1−(y+z);
- 0<x≦0.98;
- 0.01≦y≦0.5;
- and
- 0.01≦z≦0.5.
Dependencies are inferred from the claim text.