Tri-color white light led lamp

US7642708B2 · kind B2 · utility

Assignee

• KONINKLIJKE PHILIPS ELECTRONICS NV · NL

Inventors

• Thomas Juestel · Aachen, DE
• Walter Mayr · Alsdorf, DE
• Peter Josef Schmidt · Aachen, DE
• Gerd O. Muller · Berlin, DE
• Regina Muller-Mach · Mühldorf a. Inn, DE

Key dates

• Filing date: Mar 21, 2003
• Grant date: Jan 5, 2010
• Expiry date: May 13, 2024

Classification

• Technology area (CPC Y): Emerging Cross-Sectional Technologies
• CPC primary: Y02B20/00
• WIPO field: Basic materials chemistry
• WIPO sector: Chemistry

Abstract

The invention relates to a tri-color lamp for generating white light comprising a phosphor composition comprising a phosphor of general formula (Ba1−x−y−z−SrxCay)2SiO4:Euz, wherein 0≦x≦1, 0≦y≦1 and 0<z<1. The phosphor composition may also comprise a red phosphor. The two phosphors can absorb radiation emitted by a light emitting diode, particularly a blue LED. This arrangement provides a mixing of three light sources—light emitted from the two phosphors and unabsorbed light from the LED. The invention also relates to an alternative to a green LED comprising a single green phosphor of general formula (Ba1−x−y−z −SrxCay)2SiO4:Euz, wherein 0≦x≦1, 0≦y≦1 and 0<z<1, that absorbs radiation from a blue LED. A resulting device provides green light of high absorption efficiency and high luminous equivalent values.