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:
Jan. 21, 1997
Filed:
Apr. 06, 1995
Ando Electric Co., Ltd., Tokyo, JP;
Nippon Telegraph and Telephone Corporation, Tokyo, JP;
Abstract
An optical polarization controller comprises a polarization control element, a polarizer, a light divider and a photo-detector. The polarization control element rotates a plane of polarization of an Input signal light by a rotation angle in a predetermined rotational direction and outputs the result as a rotated signal light. The polarizer extracts a component of the rotated signal light having a predetermined plane of polarization and outputs the component as a polarized signal light. The light divider divides the polarized signal light into a plurality of polarized signal lights which have the same planes of polarization as the plane of the polarized light outputted by the polarizer. The photo-detector detects a level of one of the plurality of polarized signal lights and supplies a control signal indicating the level to the polarization control element. Under this control, the plane of polarization of the signal light outputted by the polarization control element is controlled so as to correspond to the plane of polarization of the light divider.