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:
May. 27, 2014
Filed:
Mar. 14, 2011
Chie Fukuda, Yokohama, JP;
Chie Fukuda, Yokohama, JP;
Sumitomo Electric Industries, Ltd., Osaka, JP;
Abstract
A semiconductor laser includes a gain region; a distributed Bragg reflector (DBR) region including a diffraction grating; an end facet facing the DBR region with the gain region arranged therebetween; a first ring resonator including a first ring-like waveguide and a first optical coupler; a second ring resonator including a second ring-like waveguide and a second optical coupler; and an optical waveguide that is optically coupled to the end facet and extending in a predetermined optical-axis direction. The first and second ring resonators are optically coupled to the optical waveguide through the first and second optical couplers, respectively. Also, the DBR region, the gain region, and the end facet constitute a laser cavity. Further, the first ring resonator has a free spectral range different from a free spectral range of the second ring resonator.