Optical amplifier for bidirectional wavelength multiplex optical transmission system

摘要

The optical amplifier has parallel amplifier elements (OV1,OV2) respectively amplifying signals of 2 different wavelengths fed in opposite directions. Wavelength-selective couplers (WDM1.WDM2) are provided between the optical transmission lines and each end of the parallel circuit for switching between the input of one amplifier element and the output of the other amplifier element. The intersection points of the 2 transmission curves for each of the couplers lie at different wavelengths.