Light source with a light-emitting element

US7187011B2 · kind B2 · utility

Assignee

• TOYODA GOSEI CO., LTD. · JP

Inventors

• Stefan Tasch · Fehring, AT
• Peter Pachler · Graz, AT
• Gundula Roth · Levenhagen, DE
• Walter Tews · Greifswald, DE
• Wolfgang Kempfert · Bad Liebenstein, DE
• Detlef Starick · Berlin, DE

Key dates

• Filing date: Oct 26, 2004
• Grant date: Mar 6, 2007
• Expiry date: Oct 26, 2024

Classification

• Technology area (CPC Y): Emerging Cross-Sectional Technologies
• CPC primary: Y02B20/00
• WIPO field: Electrical machinery, apparatus, energy
• WIPO sector: Electrical engineering

Abstract

The invention relates to a light source comprising a light-emitting element, which emits light in a first spectral region, and comprising a luminophore, which comes from the group of alkaline-earth orthosilicates and which absorbs a portion of the light emitted by the light source and emits light in another spectral region. According to the invention, the luminophore is an alkaline-earth orthosilicate, which is activated with bivalent europium and whose composition consists of: (2-x-y)SrOx(Ba, Ca)O (1-a-b-c-d)SiO2 aP2O5 bAl2O3 cB2O3 dGeO2: y Eu2+ and/or (2-x-y)BaO x((Sr, Ca)O (1-a-b-c-d)SiO2 aP2O5 bAl2O3 cB2O3 dGeO2: y Eu2+. The desired color (color temperature) can be easily adjusted by using a luminophore of the aforementioned type. The light source can contain an additional luminophore selected from the group of alkaline-earth aluminates, activated with bivalent europium and/or manganese, and/or can contain an additional red-emitting luminophore selected from the group Y(V, P, Si)O4:Eu or can contain alkaline-earth magnesium disilicate.