Method and apparatus for performing wavelength-conversion using phosphors with light emitting diodes

US6404125B1 · kind B1 · utility

Assignees

• Sarnoff Corporation · US
• EMCORE CORPORATION · US

Inventors

• Dmitri Zalmanovich Garbuzov · Princeton, US
• John C. Connolly · Clarksburg, US
• Robert F. Karlicek, Jr. · Flemington, US
• Ian Ferguson · Princeton, US

Key dates

• Filing date: Oct 20, 1999
• Grant date: Jun 11, 2002
• Expiry date: Oct 20, 2019

Classification

• Technology area (CPC H): Electricity
• CPC primary: H10H29/142

Abstract

An apparatus comprises an active region, a phosphor layer and a substrate. The active region is configured to emit light having a first band of wavelengths selected from a first group of wavelengths. The phosphor layer has a first refractive index. The phosphor layer includes a plurality of wavelength-converting phosphors. The phosphor layer is configured to convert the first band of wavelengths of light emitted from the active region to a second band of wavelengths. A center wavelength of the second band of wavelengths is greater than a center wavelength of the first band of wavelengths. The substrate is disposed between and in contact with the active region and the phosphor layer. The substrate has a second refractive index. The first refractive index substantially equals the second refractive index.