针对光电经纬仪室内检测作用距离问题，提出光电经纬仪作用距离指标的室内检测模型。从对目标进行跟踪捕获的实际工作过程中的4个边界点出发，检测光电经纬仪的目标对比度指标，并在此基础上结合天气条件参数对作用距离进行估算。由实验结果可知，该光电经纬仪目标对比度范围为5%~13%；在北纬45°，7月，白天的无云无雨天气条件下，作用距离为30.105 km，与实际外场跟飞结果相比，误差约为1 km。该方法适用于跟踪天空背景下的目标时的作用距离估算。

Aiming at the operating distance of photoelectric theodolite indoor detection, we proposed an indoor model for testing the photoelectric theodolite range index. Starting from 4 boundary points in practical work process of the target tracking, we detected the photoelectric theodolite target contrast index, then estimated the working range by taking into account the weather conditions. The experimental results show that the photoelectric theodolite target contrast range is 5%~13%; On the condition of 45°N, July, a no rain and no clouds day, the operating range is 30.105 km, and compared with the actual field flying result the error is about 1 km. This method is suitable for estimating the effect distance when tracking the targets under sky background.