设计了一种电光Q开关消光比测试系统,将整个系统分为主光路和监视光路,主光路由起偏器、检偏器、电光晶体、主探测器组成,用于测量电光晶体在加压和不加压的情况下的透射光功率;用一个监视探测器测量监视光路的透射光功率以便校正激光器的功率波动的影响。对起偏器和检偏器的透过率、自身消光比,激光器功率的波动,激光器功率的大小,激光器的偏振态,电光晶体的外加电压对电光Q开关消光比测量的影响逐一进行了分析。利用所设计的电光Q开关消光比测试系统进行了影响因素的验证实验,最后提出了消除或减小这些因素的影响的措施。 A test system of electro-optic Q switch extinction ratio is designed. The whole system is divided into the main optical path and the monitoring optical path. The main optical path consists of a polarizer, an analyzer, an electro-optical crystal and a main detector. And the transmitted light power in the absence of pressure; using a monitoring detector to measure the transmitted light power of the monitoring light path in order to correct for the effects of laser power fluctuations. The influence of polarizer and analyzer’s transmittance, extinction ratio, laser power fluctuation, laser power, laser’s polarization state and electro-optic crystal’s applied voltage on extinction ratio measurement of electro-optic Q switch were analyzed one by one . The experiment of influencing factors was carried out by using the designed test system of extinction ratio of electro-optic Q switch, and finally the measures to eliminate or reduce the influence of these factors were put forward.