Fiber amplifier for multiple signals with different wavelengths using a wavelength demultiplexer and a wavelength division multiplexer

摘要

The fibre amplifier amplifies several optical signals with different wavelengths and includes a doped fibre and a pump laser. A loss element forming part of a wavelength division multiplexer (WDM) is included in the doped fibre. Signals of equal level are generated between the multiplexer and a wave- length division demultiplexer using damping devices which compensate for the different amplification of the individual wavelengths. An optical isolator is provided in series with the wavelength division multiplexer and demultiplexer. A multi-coupler can be used in place of the wavelength multiplexer.