基于近红外或短波红外脉冲激光照明的距离选通成像(RGI)技术能够有效降低后向散射的影响，提高夜间以及恶劣环境下光电成像系统的作用距离。针对近红外RGI系统的设计与分析需要，研究提出RGI系统的作用距离模型和预测方法，即在按照传统连续(被动)成像模式计算或测试RGI系统最小可分辨对比度（MRC）性能的基础上，采用曝光时间积分等效的原理，折算周期性脉冲激光的成像效果，进而采用等效条带图案方式预测RGI系统对不同目标的作用距离。该方法预测结果与实际系统实验结果具有较好的一致性，表明该方法的有效性。该方法可用于各种近红外RGI系统的设计与性能分析，也可适用于短波红外RGI系统的作用距离预测。

The range-gated imaging (RGI) technique based on near-infrared or short-wave infrared pulsed laser illumination can reduce the influence of backscatter effectively, so it can improve the operating distance of the optical imaging system in night and adverse environment. It is researched and brought forwards the operating distance model and the forecasting method of the RGI system according to the needs of the design and analysis of near-infrared RGI system, that is according to the traditional continuous (passive) imaging model calculations or test the performance of RGI system, based on the minimum resolvable contrast (MRC), using an equivalent exposure time integration principle, imaging results of periodic pulsed laser are converted, and then the equivalent band patterns RGI system is used for predicting the role of different target distances. The forecasting results and the actual experimental results have good consistency which indicate that the method is effective. This method can be used to analyze the design and function in many kinds of near-infrared RGI system, and may also apply to forecast the operating distance in the short-wave infrared system.