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:
Oct. 30, 2012
Filed:
Jul. 06, 2011
Yasumasa Kawakita, Tokyo, JP;
Hitoshi Shimizu, Tokyo, JP;
Takeo Kageyama, Tokyo, JP;
Furukawa Electric Co., Ltd., Tokyo, JP;
Abstract
A surface emitting laser includes a cavity region formed on a group-III-V compound substrate, which includes an active layer and a current confinement layer that has an aluminum oxide compound and confines a current path through which a current is injected into the active layer, an upper DBR mirror and a lower DBR mirror formed on the substrate, sandwiching the cavity region, and a graded-composition layer disposed to contact the current confinement layer, which has an aluminum composition ratio decreasing monotonically as a distance from the current confinement layer increases. The graded-composition layer includes a first region that contacts the current confinement layer and an oxidation stop layer that contacts the first region and that has a change rate of the aluminum composition ratio larger than that of the first region. The graded-composition layer is oxidized from an interface with the current confinement layer to at least a portion of the oxidation stop layer.