| 摘要 |
PROBLEM TO BE SOLVED: To stably perform time division multiplex of signal light of plural channels, altogether with simplified structure. SOLUTION: This circuit is provided with a light frequency selecting means 14 to multiplex a signal light of N channels with light frequencies fS1 , fS2 to fSN, which differ with one another and a pump light pulse column in which N pieces of pulse with the light frequencies fP1 , fP1 , to fPN which are different from one another are successively repeated, to input it in a four-light waves mixing circuit 13, to select and to output four-light waves mixed light with one light frequency from the outputted light. The light frequency of the signal light and the light frequency of the pump light pulse column are defined as 2fP1 -fS1 =2fP2 -fS2 =...=2fPN-fSN or 2fS1 -fP1 =2fS2 -fP2 =...=2fSN-fPN and the light frequency selected by the light frequency selecting means 14 is defined as 2fP1 -fS1 or 2fS1 -fP1 . |
