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. 19, 2000
Filed:
Jul. 08, 1998
Shinya Inagaki, Kawasaki, JP;
Keiko Takeda, Kawasaki, JP;
Fujitsu Limited, Kawasaki, JP;
Abstract
With a dispersion compensating fiber 1, a dispersion compensating fiber material having a dispersion characteristic which is opposite to a dispersion characteristic of an optical transmission path, is formed with a rare-earth element doped region limited to an output side predetermined range of the full length of the fiber, while an input side region 1n is not doped with a rare-earth element. Due to this construction, signal light is amplified inside the doped region 1d even with low power excitation light, so that insertion losses in the dispersion compensating fiber are compensated. Moreover, by providing the dispersion compensating fiber between two stage optical amplifying sections, the noise factor for the overall optical amplifying section is reduced.