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:
Apr. 05, 2005
Filed:
Jun. 28, 2002
Kiyotaka Murashima, Yokohama, JP;
Ken Hashimoto, Yokohama, JP;
Toru Iwashima, Yokohama, JP;
Sumitomo Electric Industries, Ltd., Osaka, JP;
Abstract
In a diffraction grating device (), index modulations are formed along the longitudinal direction of an optical fiber () serving as an optical waveguide. The optical fiber () has a core region (), an inner cladding region (), and an outer cladding region () sequentially from the optical axis center. Index modulations are formed in both the core region () and the inner cladding region () of the optical fiber () in each of a plurality of regions Ato A(N is an integer; N≧2) separated from each other along the longitudinal direction of the optical fiber (). In the diffraction grating device (), regions A(n=1 to N) in which index modulations are formed in both the core region () and the inner cladding region () and regions B(n=1 to N−1) in which no index modulations are formed alternately exist along the longitudinal direction.