Patent ID: 6661570
Filing Date: 2003-12-09
Classification: H01S,H04B

Abstract:
An optical amplifier disposed on an optical transmission line through which a plurality of channels of signals included in a predetermined wavelength band propagate, said optical amplifier comprising:a first branching device for tapping part of light including said signals propagating through said optical transmission line; a first light-receiving device for detecting a power of said part of light tapped by said first branching device; an amplification optical fiber for amplifying said signals; a pumping light source for supplying pumping light of a predetermined wavelength to said amplification optical fiber; a delay medium arranged between said first branching device and said amplification optical fiber; and a control system for carrying out automatic gain control, said control system controlling said pumping light source by monitoring said power of said part of light tapped by said first branching device through said first light-receiving device and regulating a power of said pumping light in conformity to a power fluctuation of said tapped part of light.