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:
May. 18, 2004
Filed:
Mar. 05, 2002
Tadayuki Inaba, Sakura, JP;
Shigeru Emori, Sakura, JP;
Naoki Shamoto, Sakura, JP;
Kuniharu Himeno, Sakura, JP;
Fujikura Ltd., Tokyo, JP;
Abstract
The present invention provides a polarization maintaining optical fiber of which polarization crosstalk characteristic is not deteriorated after fusing two or more polarization maintaining optical fibers, and provides a method for producing a preform thereof. The polarization maintaining optical fiber includes two stress applying portions disposed in a cladding around a core, in which an angle formed by a line connecting the center of one of the stress applying portions with the center of the core and a line connecting the center of the other stress applying portion with the center of the core is 3 degrees or less. The preform is produced by forming one insertion hole in a cladding element and then rotating the preform 180 degrees around a core element without moving the drilling tool, followed by forming the other insertion hole in the cladding element and then inserting stress applying elements into the insertion holes.