Narrow linewidth MOPA optical fiber amplifier

The utility model discloses a narrow linewidth MOPA optical fiber amplifier, narrow linewidth MOPA optical fiber amplifier is through setting up triport circulator A between preceding stage amplifierstage light path structure and back level amplifier stage light path structure to be used for the optical filtering structure of filtering SBS light in 3 settings of port of triport circulator A, utilize the unidirectional flux nature and the optical filtering structure of circulator, effectively the stimulated brillouin scattering light that produces of filtering owner amplifier stage. 本实用新型公开了种窄线宽MOPA光纤放大器，窄线宽MOPA光纤放大器通过在前级放大级光路结构和后级放大级光路结构之间增设三端口环形器A，并在三端口环形器A的端口3处设置用于滤除SBS光的滤光结构，利用环形器的单向导通性和滤光结构，可有效滤除主放大级产生的受激布里渊散射光。