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. 02, 2015
Filed:
Nov. 29, 2012
Applicant:
Hitachi, Ltd.;
Inventors:
Kohei Mandai, Tokyo, JP;
Nobuhiko Kikuchi, Tokyo, JP;
Assignee:
Hitachi, Ltd., Tokyo, JP;
Attorney:
Primary Examiner:
Assistant Examiner:
Int. Cl.
CPC ...
G02B 6/26 (2006.01); H04B 10/50 (2013.01); H04B 10/2507 (2013.01); G02B 6/27 (2006.01);
U.S. Cl.
CPC ...
G02B 6/26 (2013.01); H04B 10/501 (2013.01); H04B 10/2572 (2013.01); G02B 6/272 (2013.01); G02B 6/2793 (2013.01);
Abstract
A PDL compensation technique is provided that reduces the number of and the number of types of the PDL compensators even if it is uncertain to determine which of the two polarization principal axes of an optical device has a larger loss. The PDL compensator according to the present invention is configured to, before an optical signal input from a first or a second input/output terminal enters a PDL compensation device, switch between the first polarization principal axis and the second polarization principal axis of the optical signal depending on which of the first and the second polarization principal axes has a larger loss or gain.