Optical system for improving optical frequency shift stability of cold atom gravimeter

The invention discloses an optical system for improving the optical frequency shift stability of a cold atom gravimeter, and the system comprises a laser, an electro-optical modulator EOM, a first optical fiber coupling head, an optical fiber, a second optical fiber coupling head, an acousto-optic modulator AOM, a first reflector, a 1/4 lambda wave plate, a half-wave plate, a first polarization splitting prism PBS, a liquid crystal phase delayer, and a second reflector which are located on the same optical axis. The EOM radio frequency source, the AOM radio frequency source and the liquid crystal phase delayer power supply are respectively connected with the EOM, the AOM and the liquid crystal phase delayer; according to the invention, the optical power and polarization of the Raman light and the power ratio stability feedback control loop of different components are added at the proper position of the Raman light transmission link, so that the impact caused by environmental change can be reduced, the stabili