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. 06, 1999
Filed:
Nov. 14, 1997
Yutaka Nagai, Tokyo, JP;
Mitsubishi Denki Kabushiki Kaisha, Tokyo, JP;
Abstract
A semiconductor laser includes a first conductivity type semiconductor substrate; a first conductivity type lower cladding layer, an active layer, and a second conductivity type first upper cladding layer, disposed in this order on the first conductivity type semiconductor substrate; a second conductivity type current confinement layer disposed on the first upper cladding layer, made of a semiconductor material containing a higher composition ratio of Al than the first upper cladding layer and having a stripe shape with a width and extending in a direction; and a second conductivity type second upper cladding layer made of the same material as the first upper cladding layer, disposed on the current confinement layer so that a central longitudinal axis of the current confinement layer is located directly opposite a central longitudinal axis of the current confinement region, and having a ridge structure with a bottom surface facing the first upper cladding layer, in contact with, and having a width larger than the current confinement layer, the grooves limiting the area in which current can flow between the lower cladding layer and the first upper cladding layer, eliminating leakage current that is not effective in generating light.