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. 25, 2012
Filed:
Jun. 16, 2009
Kohei Mandai, Tokyo, JP;
Nobuhiko Kikuchi, Tokyo, JP;
Kohei Mandai, Tokyo, JP;
Nobuhiko Kikuchi, Tokyo, JP;
Hitachi, Ltd., Tokyo, JP;
Abstract
An optical balanced receiver including an optical coupler for combining input optical information signal and optical reference signal and outputting two optical interfering signals whose phases are opposite to each other, two photodetectors for receiving the two optical interfering signals and outputting detection signals as electrical signals having the amplitudes corresponding to the interference intensities of the received optical interfering signals, a balance compensation type difference device for compensating an intensity fluctuation component added to a difference signal of the two detection signals due to the difference in amplitude and/or delay between the detection signals output from the two photodetectors in accordance with an input control signal, and outputting the compensated difference signal of the two detection signals, and a control circuit for outputting the control signal to the balance compensation type difference device.