Abstract: A luminescent powder (1) with luminescent particles (2) having an average luminescent-particle size (3) selected from the range of from 0.1 ?m inclusive to 5.0 ?m inclusive. The luminescent particles comprise primary particles (4) having an average primary-particle size (5) selected from the range of from 0.1 ?m inclusive to 1.0 ?m inclusive. The primary particles which, for example, consist of a cerium-doped yttrium-aluminum garnet (Y3Al5O12), are agglomerated to form the luminescent particles. A method for producing the luminescent powder has the following steps: a) preparing at least one precursor of the primary particles, b) producing the primary particles from the precursor of the primary particles, and c) forming the luminescent particles of the luminescent powder from the primary particles. The precursor for Y3Al5O12 is, for example, a powder mixture of hydroxides.
Type:
Grant
Filed:
May 28, 2003
Date of Patent:
January 27, 2009
Assignees:
Osram Opto Semiconductors GmbH, Patent-Treuhand-Gesselschaft für elektrische Glühlampen mbH
Inventors:
Frank Jermann, Markus Richter, Wolfgang Rossner, Martin Zachau
Abstract: A luminescent powder (1) with luminescent particles (2) having an average luminescent-particle size (3) selected from the range of from 0.1 ?m inclusive to 5.0 ?m inclusive. The luminescent particles comprise primary particles (4) having an average primary-particle size (5) selected from the range of from 0.1 ?m inclusive to 1.0 ?m inclusive. The primary particles which, for example, consist of a cerium-doped yttrium-aluminum garnet (Y3Al5O12), are agglomerated to form the luminescent particles. A method for producing the luminescent powder has the following steps: a) preparing at least one precursor of the primary particles, b) producing the primary particles from the precursor of the primary particles, and c) forming the luminescent particles of the luminescent powder from the primary particles. The precursor for Y3Al5O12 is, for example, a powder mixture of hydroxides.