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:
Dec. 11, 1979
Filed:
Oct. 06, 1977
Michiharu Nakamura, Tokyo, JP;
Junichi Umeda, Hachioji, JP;
Hitachi, Ltd., , JP;
Abstract
A semiconductor laser device comprises an n-type GaAs layer, an n-type GaAlAs layer disposed on the n-type GaAs layer, a laser active layer consisting of a p-type GaAs layer disposed on the n-type GaAlAs layer, a first p-type GaAlAs layer disposed on the laser active layer, the surface of which opposing said laser active layer is a periodically corrugated surface, a second p-type GaAlAs layer disposed on the periodically corrugated surface of the first p-type GaAlAs layer, a p-type GaAs layer disposed on the second p-type GaAlAs layer, and electrodes disposed on the n-type and p-type GaAs layers, respectively, and having a very low threshold value for laser oscillation.