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:
Jun. 25, 2002
Filed:
Jun. 02, 2000
Atsushi Ogino, Tokyo, JP;
Masaru Fukushima, Tokyo, JP;
Yoshihiro Emori, Tokyo, JP;
Haruki Ogoshi, Tokyo, JP;
Yoshio Tashiro, Tokyo, JP;
The Furukawa Electric Co., Ltd., Tokyo, JP;
Abstract
In an optical amplifier having a plurality of rare earth doped optical fibers in a multi-stage, there are provided one or more optical variable attenuator means, and an attenuation amount control means for changing an optical attenuation amount of the optical variable attenuator means on the basis of temperature of the rare earth doped optical fibers or an environmental temperature. In an optical amplifier having a plurality of rare earth doped optical fibers in a multi-stage, between the rare earth doped optical fibers, there are provided a replaceable optical part, one or more optical variable attenuator means, and an attenuation amount control means for changing an optical attenuation amount of the optical variable attenuator means on the basis of temperature of the rare earth doped optical fibers or an environmental temperature. In an optical amplifier having a plurality of rare earth doped optical fibers in a multi-stage, one or more externally controllable optical variable attenuator means are provided, and an optical attenuation amount of the optical variable attenuator means is varied with intensity of input optical signal to the optical amplifier and intensity of output optical signal from the optical amplifier.