Patent ID: 6823107
Filing Date: 2004-11-23
Classification: H01S

Abstract:
A device comprising:a first optical amplifying unit comprising a Raman amplifying medium and a first pump source for pumping said Raman amplifying medium, for amplifying signal lights propagated through said Raman amplifying medium in one direction, said first pump source outputting a plurality of pump lights having different wavelengths; a second optical amplifying unit optically connected to a rear stage of said first optical amplifying unit, said second optical amplifying unit comprising an optical amplifying medium and a second pump source for pumping said optical amplifying medium; and a control unit for controlling the gain of said first optical amplifying unit so as to cancel variations in output power of said first optical amplifying unit due to variations in input power of said first optical amplifying unit; means for detecting the spectrum of spontaneous Raman scattering light generated in an propagated through said Raman amplifying medium in the other direction; and means for controlling a balance of power of said plurality of pump lights according to the spectrum of said spontaneous Raman scattering light detected.