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:
Jan. 01, 1991
Filed:
Sep. 05, 1989
Hideaki Kinoshita, Yokohama, JP;
Naohiro Shimada, Kawasaki, JP;
Kabushiki Kaisha Toshiba, Kawasaki, JP;
Abstract
A semiconductor laser device comprises a substrate formed of elements of the III-V groups and having one conductivity type, a lower clad layer formed on the substrate and having the same conductivity type as that of the substrate, and an upper clad layer formed on the lower clad layer and having a conductivity type opposite to that of the lower clad layer. A waveguide layer having a large refractive index is formed within the lower clad layer by decreasing the band gap of the upper clad layer. The light generated in an activation layer is guided to the lower clad layer, so as to suppress adverse effects which the upper clad layer may have on element characteristics.