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:
Jun. 09, 2009
Filed:
Feb. 25, 2004
Yutaka Kai, Kawasaki, JP;
Hideyuki Miyata, Kawasaki, JP;
Yutaka Kai, Kawasaki, JP;
Hideyuki Miyata, Kawasaki, JP;
Fujitsu Limited, Kawasaki, JP;
Abstract
Signal light with a specific wavelength is transmitted and extracted from signal light multiplexed by a WDM method, and a light detection unit detects the signal light detected by an optical tunable filter, whose wavelength transmission characteristic varies depending on a control signal. An operation circuit generates information for designating a control signal needed to enable the optical tunable filter to extract signal light with a designated wavelength, based on the detected results of two segments of signal light located at each edge of a wavelength band obtained by shifting the wavelength transmission characteristic of the optical tunable filter from outside the wavelength band including all segments of the entire WDM signal. A driving circuit generates a control signal according to the designation information.