采用数值模拟和实验相结合的方法对脉冲激光二极管(LD)抽运Nd:YAG被动调Q激光器输出脉冲间隔特性进行分析。从被动调Q速率方程出发，结合脉冲LD抽运的特点，考虑剩余反转粒子数密度的影响，推导出输出调Q脉冲间隔时间的计算公式。重点分析了抽运脉宽、输出镜反射率、抽运功率和Cr4+:YAG初始透射率对输出脉冲间隔时间的影响。结果表明，数值模拟与实验结果基本吻合。

A passively Q-switched Nd:YAG laser pumped by diode pulse is set up. The characteristics of the laser pulse intervals are analysed by combining numerical simulation and experimental method. Starting with the rate equation of passively Q-switching mode, the Q-switched pulse intervals are formulated in consideration of the feature of diode pulse pumping and the influence of surplus inverse population density. The in fluence of pumping current and pulse width, the reflectivity of output mirror and the initial transmission of Cr4+:YAG on pulse interval time is analysed enphatically. The result indicates that the numerical simulation of pulse interval time coincides with the experimental data.