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. 05, 1989
Filed:
Oct. 07, 1988
Applicant:
Inventors:
Makoto Okai, Koganei, JP;
Kazuhisa Uomi, Hachioji, JP;
Shinji Tsuji, Red Bank, NJ (US);
Shinji Sakano, Hachioji, JP;
Naoki Chinone, Chofu, JP;
Assignee:
Hitachi, Ltd., Tokyo, JP;
Attorney:
Primary Examiner:
Assistant Examiner:
Int. Cl.
CPC ...
H01S / ;
U.S. Cl.
CPC ...
372 45 ; 372 46 ; 372 50 ; 372 96 ;
Abstract
A tunable semiconductor laser device has an active region for generating light, and a feedback region which is optically coupled with the active region and includes a perturbation portion having non-uniform perturbation period. In this semiconductor laser device, the light intensity distribution in the feedback region is changed to vary the degree of coupling of light propagated in the feedback region with a desired part of the perturbation portion, thereby varying the wavelength of emitted light.