Optical amplifier and optically amplifying method

Abstract

Disclosed is an optical amplifier, comprising: at least one optically amplifying unit having: a forward excitation light source for generating a forward excitation light; a forward excitation light coupler for coupling the forward excitation light with an input optical signal; an optically amplifying medium for amplifying the input optical signal combined with the forward excitation light; a backward excitation light source for generating a backward excitation light; a backward excitation light coupler for coupling the backward excitation light with the amplified optical signal; a first controller for controlling the forward excitation light source to generate the forward excitation light with a power up to a maximum power thereof; and a second controller for controlling the backward excitation light source to generate the backward excitation light in such a way that the backward excitation light compensates gain deficiency as compared with a desired gain of the optical amplifier.

Dependencies are inferred from the claim text.