An optical repeater

摘要

The invention relates to an optical amplifier for use as an optical repeater in a high capacity wavelength division multiplexed optical communications system. The repeater (1) has a multi-stage optical amplifier in which a first optical amplifier stage (4) is pumped at a first wavelength by a first pump source (3) and a second optical amplifier stage (6) is pumped at a second wavelength by a second optical pump source (5). An optical processing element (7) is positioned between the first amplifier stage (4) and the second amplifier stage (6) to condition the output of the first amplifier stage (4) and an optical coupler (2) is adapted to couple the pump sources to the respective optical amplifiers. This amplifier topology provides tight dispersion control of high capacity optical transmission.