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:
Aug. 26, 2008
Filed:
Mar. 15, 2005
Kazuhiko Hatae, Kawasaki, JP;
Nobukazu Koizumi, Kawasaki, JP;
Masato Oota, Kawasaki, JP;
Fujitsu Limited, Kawasaki, JP;
Abstract
An optical amplification device is disclosed that performs feedback control to maintain an amplification gain to be a constant based on measured power of input light and power of output light. The device includes a feedback control coefficient switching unit configured to, when performing the feedback control on a difference from an object amplification gain, distinguish a state of increasing or decreasing the number of frequencies of the input light and a steady state by making comparison and determination whether an amplitude of at least one of the power of the input light and the power of the output light is in a predetermined range, and switch the feedback control coefficient. Therefore, it is possible to reduce variation of the power of the output light caused by noise in the steady state without affecting operations of increasing and decreasing a number of frequencies of a light signal.