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:
Sep. 17, 2002
Filed:
Nov. 09, 2000
Shinji Endo, Yokohama, JP;
Sumitomo Electric Industries, Ltd., Osaka, JP;
Abstract
The present invention relates to a fiber optic amplifier comprising a structure enabling favorable signal amplification characteristics to be maintained even in an environment exposed to radiation. The fiber optic amplifier according to the present invention comprises a bleaching system for restoring glass defects generated within an optical fiber for amplification upon exposure to ultraviolet rays. This bleaching system carries out at least one of optical bleaching and thermal bleaching for the optical fiber for amplification. The optical bleaching is effected when bleaching light having a shorter wavelength shorter and a higher power than pumping light is supplied into the optical fiber for amplification, whereas the fiber optic amplifier has a structure which can introduce and eliminate the bleaching light. On the other hand, the thermal bleaching is effected by heating the optical fiber for amplification, whereas the fiber optic amplifier comprises a structure for maintaining the surface temperature of the optical fiber for amplification within a predetermined range.