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. 19, 2013
Filed:
Jul. 09, 2010
Yohei Sakamaki, Atsugi, JP;
Takashi Goh, Atsugi, JP;
Toshikazu Hashimoto, Atsugi, JP;
Yusuke Nasu, Atsugi, JP;
Kuninori Hattori, Atsugi, JP;
Hiroshi Takahashi, Atsugi, JP;
Yohei Sakamaki, Atsugi, JP;
Takashi Goh, Atsugi, JP;
Toshikazu Hashimoto, Atsugi, JP;
Yusuke Nasu, Atsugi, JP;
Kuninori Hattori, Atsugi, JP;
Hiroshi Takahashi, Atsugi, JP;
Nippon Telegraph and Telephone Corporation, Tokyo, JP;
Abstract
An optical 90-degree hybrid circuit includes a first demultiplexing optical coupler having two or more first input ports and two or more first output ports, a second demultiplexing optical coupler having two or more second input ports and two or more second output ports, two first arm waveguides connected to the first output ports, two second arm waveguides connected to the second output ports, a 90-degree phase shift section installed in one of the four arm waveguides, a first optical coupler and a second optical coupler connected to the first arm waveguides and the second arm waveguides, a first optical waveguide for connecting an optical splitter and the first input ports, and a second optical waveguide for connecting the optical splitter and the second input ports, wherein an optical length of the first optical waveguide is different from that of the second optical waveguide.