OPTICAL AMPLIFIER AND OPTICAL COMMUNICATION SYSTEM PROVIDED WITH WAVELENGTH DISPERSION COMPENSATING FUNCTION, AND WAVELENGTH DISPERSION COMPENSATING METHOD FOR WAVELENGTH MULTIPLEX SIGNAL LIGHT

摘要

PROBLEM TO BE SOLVED: To provide an optical amplifier and an optical communication system which are simple in configuration and capable of compensating the wavelength dispersion of the wavelength multiplex signal light of a wide band and to provide a wavelength dispersion compensating method for wavelength multiplex signal light which reduces the probability of causing a nonlinear optical effect. SOLUTION: This optical amplifier divides the wavelength multiplex signal light sent from an optical transmission path into 1.55 μm band and 1.58 μm band by a WDM coupler 1 to send them to optical fiber amplifying parts 2 and 3 for each wavelength band. Then, the signal light of each wavelength band passing through each variable light attenuator 22 and 32 is temporarily multiplexed by a WDM coupler 10 to send it to DCF 11, then respective dispersions of each wavelength band are compensated altogether. In addition, the signal light passing through DCF 11 is divided again by a WDM coupler 12, is amplified by the optical fiber amplifiers 24 and 34 of each wavelength band, and is sent to an optical transmission path through a WDM coupler 4 and an optical coupler 13.