Er ³⁺ doped fibre amplifier operating atwavelengths of 1.55 and 1.60 µm

An erbium doped fibre (EDF) amplifier operating at two wavelengths of 1.55 and 1.6 µm was constructed using a single 0.98 µm pump LD. A reflection structure was applied using optical fibre gratings (FBG). Optical signals with wavelengths of around 1.55 and 1.6 µm are selectively reflected at a middle point between the EDF and a fibre end by the FBGs. Optical gains were 27 dB at 1.55 µm and 17 dB at 1.6 µm, which are high enough for a booster optical amplifier applied to an optical time domain reflectometer.