As the laser pulse frequency is low and the pulse’s width is ns grade in the pulse laser detection system ,it’s difficult to control the accurate exposure moment of the digital CCD camera .In order to overcome the difficulty that the trigger signal for the digital CCD camera and the laser pulse signal are not synchronous , a method that combining the “light trigger ,electrical synchronization” with advanced prediction is put for-ward .BD2/GPS module provided the PPS pulse signal as the clock reference ,combined with the FPGA’s high speed characteristic ,so the digital CCD camera could capture the laser spot image exactly ,and control the best integral time of the digital CCD camera .The experiment indicates that this method can improve the capturing precision of the digital CCD camera and the SNR of laser spot image .%脉冲激光检测系统中，由于激光器发射的激光脉冲频率低，且脉宽仅为纳秒级，所以在远距离测试时，很难控制数字 CCD（Charge Coupled Device）相机的精准曝光时刻。为了克服触发信号与激光脉冲信号不同步的问题，本文提出了“光触发，电同步”与“超前预测”相结合的方法。以 BD2（BeiDou2 Navigation Satel-lite System ）/GPS（Global Positioning System ）模块提供的精确秒脉冲 pps（pulse per second）信号作为时钟基准，同时结合 FPGA（Field Programmable Gate Array ）高速的特点，实现数字 CCD 相机对激光光斑图像的准确捕获，控制数字 CCD 相机的最佳积分时间。实验结果表明，该方法不仅提高了数字 CCD 相机的抓拍精度，也提高了图像的信噪比。
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