Coated fluorescent substance, light emitting device comprising said substance and a method for producing said substance

US7678293B2 · kind B2 · utility

Assignees

• OSRAM Gesellschaft mit beschraenkter Haftung · DE
• OSRAM Opto Semiconductors GmbH · DE

Inventors

• Bert Braune · Völklingen, DE
• Torsten Fries · Stadtbergen, DE
• Rainer Schirmer · Bohmte, DE
• Martin Zachau · Geltendorf, DE
• Franz Zwaschka · Ismaning, DE

Key dates

• Filing date: Feb 20, 2004
• Grant date: Mar 16, 2010
• Expiry date: Feb 20, 2024

Classification

• Technology area (CPC Y): Emerging Cross-Sectional Technologies
• CPC primary: Y10T428/2991
• WIPO field: Basic materials chemistry
• WIPO sector: Chemistry

Abstract

A coated phosphor, formed by a powder of individual grains of a phosphor as base material, the grains being coated with a coating material. The layer comprises a plurality of individual layers and is particulate in form, the individual primary particles of the layer being at least 5 nm in size. The mean layer thickness is at least 20 nm.