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:
Apr. 27, 1999
Filed:
Aug. 08, 1997
Shiro Ryu, Tokyo, JP;
Kokusai Denshin Denwa Kabushiki Kaisha, Tokyo, JP;
Abstract
In an optical frequency stabilizing device for stabilizing optical frequencies of transmission lasers even when optical frequency reference is shut off, an optical shutter 44 is normally held in its open state to pass optical frequency reference light from an optical network to an injection-locked laser device 42. An optical multiplexer 46 multiplexes outputs of a injection-locked laser device 42 and transmission laser devices 40-1 through 40-3, and an optical frequency discriminator 48 scans optical output of the multiplexer 46. Opto-electrically converted output of a photodetector 52 is applied to a control device 50 which controls driving currents, etc. of the laser devices 40-1 through 40-3 to adjust optical output frequencies of the laser devices 40-1 to 40-3 to predetermined values relative to the optical output frequency of the injection-locked laser device 42. The control device 50 also closes the optical shutter 44 for a moment, and adjusts the driving current, etc. of the injection-locked laser device 42 to equalize the optical frequency of optical output of the injection-locked laser device 42 during the close state of the optical shutter 44 to the value during the open state of the optical shutter 44.