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. 22, 1992
Filed:
Jun. 21, 1991
Nobuaki Kaneno, Itami, JP;
Mitsubishi Denki Kabushiki Kaisha, Tokyo, JP;
Abstract
A semiconductor laser having a double heterojunction structure includes a first semiconductor cladding layer having a stripe-shaped groove, a semiconductor active layer disposed on the cladding layer and having an energy band gap narrower than that of the cladding layer, and a second semiconductor cladding layer disposed on the active layer and having an energy band gap wider than that of the active layer. The thickness of the active layer in the groove is larger than the thickness of the active layer outside the groove and the shape of the active layer has the shape of the groove. The thickness of the active layer is largest in the bottom of the groove and gradually becomes smaller toward the edges of the groove. The semiconductor laser can output a laser beam having nearly a circular cross-section at a low threshold current and is easily fabricated.