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. 05, 2015
Filed:
May. 20, 2013
Sumitomo Electric Industries, Ltd., Osaka, JP;
Tsutomu Ishikawa, Yokohama, JP;
Toshimitsu Kaneko, Yokohama, JP;
Sumitomo Electric Industries, Ltd., Osaka, JP;
Abstract
A semiconductor laser includes: a first reflector that is provided in a gain region and has a sampled grating in which a plurality of segments are combined; and a second reflector that is optically connected to the first reflector and has a sampled grating in which a plurality of segments are combined, the plurality of segments of the first reflector having a short-segment region and a long-segment region, the long-segment region having an optical length that is larger than that of the short-segment region and being positioned closer to the second reflector than at least one of the short-segment region, the optical length of the long-segment region being larger than that of the short-segment region in a range of integral multiple (n≧1) plus-minus 25% of the optical length of the short-segment.