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. 14, 2020
Filed:
Mar. 06, 2017
Applicant:
Fujikura Ltd., Tokyo, JP;
Inventor:
Rintaro Kitahara, Chiba, JP;
Assignee:
Fujikura Ltd., Tokyo, JP;
Attorney:
Primary Examiner:
Assistant Examiner:
Int. Cl.
CPC ...
G02B 6/36 (2006.01); G02B 6/036 (2006.01); H01S 3/067 (2006.01); H01S 3/10 (2006.01); H01S 3/08 (2006.01); G02B 6/02 (2006.01);
U.S. Cl.
CPC ...
G02B 6/03616 (2013.01); G02B 6/03605 (2013.01); G02B 6/03694 (2013.01); H01S 3/067 (2013.01); H01S 3/06729 (2013.01); H01S 3/10007 (2013.01); G02B 6/02047 (2013.01); G02B 6/03633 (2013.01); H01S 3/0675 (2013.01); H01S 3/06733 (2013.01); H01S 3/06754 (2013.01); H01S 3/08045 (2013.01); H01S 2301/03 (2013.01);
Abstract
An amplification optical fiber according to the present invention includes: a core doped with an active element, through which multi-mode light propagates; an inner cladding that surrounds the core and has a refractive index lower than that of the core; and an outer cladding that surrounds the inner cladding and has a refractive index lower than that of the inner cladding. The inner cladding has a polygonal outline in a cross section perpendicular to the longitudinal direction, and the inner cladding has a permanent twist applied by turning around the central axis of the core.