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:
Mar. 29, 2005
Filed:
May. 13, 2003
Fujio Akinaga, Kaisei-machi, JP;
Toshiaki Fukunaga, Kaisei-machi, JP;
Fujio Akinaga, Kaisei-machi, JP;
Toshiaki Fukunaga, Kaisei-machi, JP;
Fuji Photo Film Co., Ltd., Kanagawa-Ken, JP;
Abstract
In a semiconductor laser element: a lower cladding layer of a first conductive type, a lower optical waveguide layer made of InGaP which is undoped or the first conductive type, an active layer made of InGaAsPlattice-matching with GaAs (0<x3≦0.3 and 0≦y3≦0.5), an upper optical waveguide layer made of InGaP which is undoped or a second conductive type, and a first upper cladding layer of the second conductive type are formed in this order above the substrate. The lower optical waveguide layer has a bandgap which gradually decreases with elevation within the lower optical waveguide layer, and the upper optical waveguide layer has a bandgap which gradually increases with elevation within the upper optical waveguide layer.