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. 26, 2000
Filed:
Dec. 05, 1997
Yasutaka Sakata, Tokyo, JP;
NEC Corporation, Tokyo, JP;
Abstract
There is provided an optical semiconductor device including an optical waveguide structure having a quantum well layer and an optical confinement layer as a core layer, wherein the core layer has a thickness varying in a lengthwise direction of the optical waveguide to thereby have a function of spot-size conversion, and the quantum well layer is designed to have a band-gap energy which is constant within .+-.30 meV in the direction. The above-mentioned optical semiconductor device makes it possible to an optical gain to laser oscillation wavelength over all ranges of a resonator, and hence makes it no longer necessary to form a region only for spot-size conversion (SSC). This ensures that a device length can be as small as that of a conventional laser diode. In addition, lower threshold value characteristic and high temperature operation performance could be achieved, and a yield in devices per a wafer can be significantly enhanced.
Data source: USPTO (United States Patent and Trademark Office) public patent records. Weekly synchronization. How IDiyas builds this profile