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:
Jul. 22, 2003
Filed:
Sep. 27, 1999
Kunihiro Takatani, Yamatotakada, JP;
Sharp Kabushiki Kaisha, Osaka, JP;
Abstract
A compound semiconductor laser of a III group nitride semiconductor of the present invention includes a first cladding layer of a first conduction type formed on a substrate , an active layer formed on the first cladding layer, a second cladding layer of a second conduction type formed on the active layer , and a buried layer formed on the second cladding layer , the buried layer having an opening portion for constricting a current in a selected region of the active layer, wherein an upper portion of the second cladding layer has a ridge portion, the ridge portion residing in the opening portion of the buried layer , and the buried layer does not substantially absorb light output from the active layer , and the buried layer has a refractive index which is approximately identical with that of the second cladding layer