The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Mar. 17, 2020
Filed:
Sep. 26, 2013
John F. Kelso, Exeter, NH (US);
Kathleen A. Lawson, Amesbury, MA (US);
John F. Kelso, Exeter, NH (US);
Kathleen A. Lawson, Amesbury, MA (US);
OSRAM SYLVANIA INC., Wilmington, MA (US);
Abstract
An alumina-based ceramic wavelength converter is described having a surface layer containing a second phase of alumina, preferably as alumina crystallites. The surface layer is formed as a result of the sintering process used to form the bulk ceramic which is itself substantially transparent. The ceramic wavelength converter is combined with a light emitting diode to form a light emitting device. Preferably, the ceramic wavelength converter is comprised of an alumina-based phosphor represented by a general formula ABO:Ce, wherein A is Y, Sc, La, Gd, Lu, or Tb and B is Al, Ga or Sc.