在单光子脉冲测距系统中，由于光子到达时间的随机性，使探测到的目标距离具有一定的不确定性，因而单光子脉冲测距系统的测距精度受到一定的限制。基于回波光子与光电子的统计特性，研究了单光子探测器在脉冲测距系统中的脉冲强度，脉冲宽度等参数对系统测距精度的影响。针对常见的回波波形，得到了测距精度与回波脉冲强度及宽度的相互关系式。理论分析结果表明回波激光脉冲强度越高，脉冲宽度越窄，所获得的距离精度越高。

The range precision of single photon pulsed ranging system is influenced by the random arrival of echo photon. Based on the statistical property of echo photon and photoelectron, the influence of the echo signal strength and pulse width on the range precision is discussed. For normal rectangular echo signal, the relation between the range precision and signal strength and pulse width is obtained. Results show that higher signal strength and narrower pulse width produce better range precision.