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:
Nov. 27, 2007
Filed:
Apr. 14, 2004
Keiji Ito, Takatsuki, JP;
Isao Kidoguchi, Kawanishi, JP;
Toru Takayama, Nara, JP;
Osamu Imafuji, Takatsuki, JP;
Keiji Ito, Takatsuki, JP;
Isao Kidoguchi, Kawanishi, JP;
Toru Takayama, Nara, JP;
Osamu Imafuji, Takatsuki, JP;
Matsushita Electric Industrial Co., Ltd., Osaka, JP;
Abstract
A semiconductor laser device of the present invention includes: a first conductivity type cladding layer; an active layer; and a second conductivity type cladding layer, which are on a substrate. The semiconductor laser device further includes a stripe structure for injecting carriers therein. A width of the stripe is wider at a front end face of a resonator from which laser light is emitted than at a rear end face that is located on an opposite side of the front end face, and a reflectance of the front end face is lower than a reflectance of the rear end face. With this configuration, the injection of carriers into an active layer can be controlled in accordance with an optical intensity distribution along the resonator direction within the semiconductor laser, thus achieving a decrease in threshold current, an enhancement of a slope efficiency and an enhancement of a kink level. As a result, the semiconductor laser device can be provided so that stable laser oscillation in the fundamental transverse mode can be realized up to the time of a high optical output operation.