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. 16, 2025
Filed:
Sep. 02, 2020
Fujikura Ltd., Tokyo, JP;
Hiroyuki Kusaka, Chiba, JP;
Masahiro Kashiwagi, Chiba, JP;
Fujikura Ltd., Tokyo, JP;
Abstract
An optical amplification apparatus includes a first amplification optical fiber, a second amplification optical fiber, a first pumping light source, and a second pumping light source. The first amplification optical fiber includes a first core and a first cladding layer. The first core is doped with an active element using a first active element doping concentration distribution. The first cladding layer is disposed out of the first core and has a refractive index lower than the refractive index of the first core. The second amplification optical fiber is connected to the first amplification optical fiber in a longitudinal direction of the first amplification optical fiber. The second amplification optical fiber includes a second core and a second cladding layer. The second core is doped with active element using a second active element doping concentration distribution that is different from the first active element doping concentration distribution.