METHOD AND DEVICE FOR OPTICAL AMPLIFICATION, AND SYSTEM COMPRISING THE SAME

摘要

PROBLEM TO BE SOLVED: To provide a device wherein low (good) noise index and high optical output power are obtained while dependency of a gain on wavelength is suppressed, relating to a method and device for optical amplification and a system comprising the device. SOLUTION: A system comprises an optical amplifier 8 which comprises an optical amplification medium 12 having an input end 12A and an output end 12B for signal light, and a unit 14 which pumps the medium 12, so that the medium 12 provides a gain band including a first band for giving a high gain and noise index to the signal light and a second band giving a low gain and noise index; a first optical filter 6 which suppresses dependency of gain on wavelength in the second band; and a second optical filter 10 which suppresses that in the first band.