Fibre optic amplifier using pumping action laser diode

摘要

The fibre optic amplifier comprises a section of optical fibre (1) having a core which is doped with a rare earth element. A laser diode providing pumping is connected to one end of the fibre by means of a wavelength coupler. The output of the fibre is connected to an optical divider (2) which divides the output into two parts. One component is supplied to a first phase modulator (32) via at least one wavelength filter (41) which suppresses only a specific wavelength. The second component is supplied to a second phase modulator (31). The outputs of the two phase modulators are then recombined by an optical coupler (5). The two branches of the optical system may be enhanced by the addition of a polarisation controller in each branch.