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:
Aug. 10, 2004
Filed:
Sep. 12, 2002
Shuichi Hirukawa, Tenri, JP;
Sharp Kabushiki Kaisha, Osaka, JP;
Abstract
There is provided a semiconductor laser device implementing a single transverse mode oscillation in an oscillation wavelength of 780 nm band and also having high reliability and long life in high-output driving state, and an optical disk recording and reproducing apparatus with use of the semiconductor laser device. A multiple quantum well active layer is composed of InGaAsP, and a first cladding layer , a second cladding layer , a third cladding layer , and a first current blocking layer are structured from III-V group compound semiconductor containing only As as V group element. Inside the first current blocking layer , a hollow portion is provided in the vicinity of and approximately parallel to the ridge stripe-shaped third cladding layer