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:
Aug. 18, 1992
Filed:
May. 17, 1991
Fujitsu Limited, Kawasaki, JP;
Abstract
An optical fiber doped with Er is provided at its both end portions with a pair of 1.25 .mu.m band reflecting filters such that the distance therebetween becomes the resonator length for a light beam of 1.25 .mu.m band. When a pumping light beam of a wavelength of 0.8 .mu.m band is introduced into the optical fiber, laser oscillation at 1.25 .mu.m band is produced, whereby the energy level of Er in an excited state is lowered and a signal light beam of a wavelength of 1.55 .mu.m band can be optically amplified with high efficiency. Another fiber optic amplifier in which a pair of 0.98 .mu.m band reflecting filters are disposed at both end portions of an optical fiber doped with Yb and Er such that the distance therebetween becomes the resonator length for a light beam of 0.98 .mu.m band is also disclosed.