Provided are an optical relay, optical relay production method, and optical signal relay method that make it possible to achieve, with a simple configuration, redundancy against failure of a light source for outputting excitation light. In the present invention, light sources (S1-S3) output light beams (L1-L3). A light amplification unit (A1-A3) uses excitation light beams (L4-L6) to amplify lightsignals (SIG1-SIG3). A light distribution part (10) splits each of the light beams (L1-L3) output from the light sources (S1-S3) into two split light beams and distributes the split light beams suchthat each light amplification unit (A1-A3) receives, as the excitation light beams (L4-L6), split light beams obtained from the splitting of light beams from two different light sources.
OPTICAL RELAY, OPTICAL RELAY PRODUCTION METHOD, AND OPTICAL SIGNAL RELAY METHOD