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. 03, 1990
Filed:
May. 18, 1989
Saburo Yamamoto, Nara, JP;
Sharp Kabushiki Kaisha, Osaka, JP;
Abstract
A semiconductor laser device comprising an active layer sandwiched between a first semiconductor layer and a second semiconductor layer, the forbidden bandgap of each of said first and second layers being larger than that of said active layer, wherein at least one of said first and second layers has a striped projection provided with two inclined surfaces; said layer is sandwiched between said active layer and a light absorption layer; and the thickness of said layer that corresponds to the inside of the center area of each of the two inclined surfaces is thick enough so that laser light cannot permeate into said absorption layer and the thickness of said layer that corresponds to the outside of the center area of each of the two inclined surfaces is sufficiently thin so that laser light can permeate into said absorption layer, whereby the thickness of a semiconductor layer that constitutes a double-heterostructure is not required to be precisely regulated so that the laser device is not restricted by production conditions and mass-production.