Scanning filtering based on Fabry Perot etalon with electro optic crystal

A method of scanning filtering for improving the signal to noise ratio (SNR) of chirped pulse has been proposed. The method is based on Fabry Perot (F-P) etalon with electro optic crystal, and uses the principle of multi beam interference of the F-P etalon and the linear electro optic effect of the crystal. The time varying function of the voltage applied on electro optic crystal was given, and the main factors affecting the SNR were analyzed. Moreover, the effects of the control parameters of the applied voltage on the SNR and the transmittance of the filter were discussed. The results show that the SNR of chirped pulse laser can be improved nearly two orders of magnitude by using the scanning filtering method.