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:
Apr. 27, 2004
Filed:
Nov. 05, 2002
Hitachi, Ltd., Tokyo, JP;
Abstract
A semiconductor laser which has an active layer of a lattice strain of less than 2% of a thickness mean on a GaAs substrate and can be used in a long wavelength band of 1.3 &mgr;m band or more and a photo module which uses the semiconductor laser are provided. The semiconductor laser device has a first semiconductor layer and second semiconductor layers , the layer and the layers forming a type-II heterojunction structure, in which an energy of conduction band edge of said first conductor layer is larger than the energy of conduction band of said second semiconductor layers . The device has third semiconductor layers as barrier layers formed on both sides of said type-II heterojunction structure. In the device, the second semiconductor layers are arranged on both sides of the first semiconductor layer and the thickness of the first semiconductor layer is set in such a degree of thickness that a wave function of an electron of a quantum well formed by making the second semiconductor layer well layers is coupled.