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:
Sep. 18, 2012
Filed:
Nov. 19, 2009
Takashi Shimizu, Kawasaki, JP;
Koji Terada, Kawasaki, JP;
Kiyomi Narita, Kawasaki, JP;
Kazuyuki Mori, Kawasaki, JP;
Takashi Shimizu, Kawasaki, JP;
Koji Terada, Kawasaki, JP;
Kiyomi Narita, Kawasaki, JP;
Kazuyuki Mori, Kawasaki, JP;
Fujitsu Limited, Kawasaki, JP;
Abstract
A demodulator includes: a splitter that branches a differential phase shift keying optical signal into a first branched optical signal passing through a first optical path and a second branched optical signal passing through a second optical path; a multiplexer that multiplexes the first branched optical signal having passed through the first optical path and the second branched optical signal having passed through the second optical path and makes interference between the first branched optical signal and the second branched optical signal; and a double refraction medium that reduces difference between phase differences between each polarized wave between the first branched optical signal and the second branched optical signal multiplexed by the multiplexer.