Optical fiber amplifiers

摘要

A length L M of the fiber 3 of an optical fiber amplifier is set to obtain a substantially maximum saturated output power of the amplified signal light in order to achieve a flat gain and low noise across a wide wavelength band, e.g. for CATV. As described, the amplifier has an Er-doped multiple-core optical fiber. A signal of 1.5m wavelength band is input through an optical isolator 1-1, and pump signals of 0.98m or 1.48m wavelength are injected through WDM couplers 2-1, 2-2 respectively. An amplified signal is output through optical isolator 1-2.