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:
Dec. 24, 2013
Filed:
Jul. 29, 2009
Mitsuru Nagano, Yokohama, JP;
Akira Himeno, Yokohama, JP;
Masayuki Okuno, Yokohama, JP;
Masahiko Naito, Yokohama, JP;
Akihito Doi, Yokohama, JP;
Daisuke Ogawa, Yokohama, JP;
Akira Nagai, Yokohama, JP;
Mitsuru Nagano, Yokohama, JP;
Akira Himeno, Yokohama, JP;
Masayuki Okuno, Yokohama, JP;
Masahiko Naito, Yokohama, JP;
Akihito Doi, Yokohama, JP;
Daisuke Ogawa, Yokohama, JP;
Akira Nagai, Yokohama, JP;
NTT Electronics Corporation, Kanagawa, JP;
Abstract
A planar optical waveguide including a clad layer, an optical waveguide having a core embedded in the clad layer; and a groove formed in the clad layer and having a reflection interface for totally reflecting a leaked light leaked from the optical waveguide to the clad layer. Since the reflection interface for totally reflecting the leaked light is formed in the clad layer, the leaked light is prevented from entering into the tap coupler, and the variation of the branching ratio can be reduced.