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:
Nov. 28, 2006
Filed:
Sep. 17, 2004
Hidenori Nakada, Tokyo, JP;
Shusuke Wada, Tokyo, JP;
Keisuke Ikeda, Tokyo, JP;
Yuko Ota, Tokyo, JP;
FDK Corporation, , JP;
Abstract
A low-cost compact optical attenuator structure has an input port and an output port for optical signals arranged side by side; a reflecting member arranged to face both ports to reverse light from the input side on an optical path folded 180°; a birefringence crystal splits incident light into two polarization components, a converging lens converges the incident light, a fixed Faraday rotator having a variable rotation angle arranged in that order in the optical path. The partial reflecting member that transmits a portion of incident light to the rear side thereof, an optical sensor at the rear side of the reflecting member, optical guide means guide only the transmitted light from the input port side to the optical sensor, and optical detection signals of the optical sensor are used as optical input monitoring signals.