Photonic phase synchronous system

Patent Granted PROBLEM TO BE SOLVED: To provide a highly precise photonic phase synchronous system with a high long-term reliability for generating a narrow line width intermediate frequency signal of a 10 Hz or smaller line width. ; SOLUTION: The system uses as a transmission light source a fiber laser with a low phase noise and employs as a local oscillation light source a fiber laser with a low phase noise, capable of high-speed response using a piezoelectric element and a LiNbO<SB>3</SB>photonic phase modulator for an optical frequency variable mechanism.