PUMP LIGHT GENERATOR AND FIBER RAMAN AMPLIFIER

摘要

PROBLEM TO BE SOLVED: To prevent the occurrence of increasing polarization degree of an output pump light beams even though one of the pump light sources is failed. SOLUTION: Laser diodes 30a and 30b are FP-LDs made of InGaAsP which laser oscillate in a 1,480 nm band. Output light beams of the diodes 30a and 30b are made incident on a polarization beam splitter 32 while they are in mutally orthogonally polarized states and multiplexed. The multiplexed light beams by the beam splitter 32 are then made incident on a nonpolarization element 34 and nonpolarized.