通过近红外高通滤波和数字图像处理技术，可明显提升低能见度条件下光电成像系统的作用距离，但是近红外高通滤波也提高了系统的最低工作照度。根据光电成像原理，研究了超能见度光电成像系统的最低工作照度转换问题，给出了在实际光学系统F数和近红外高通滤波条件下的最低工作照度计算方法，对光电成像系统的设计分析具有理论指导作用。

The effective distance of photoelectric imaging system can be improved obviously under the conditions of low visibility through the near-infrared high-pass filtering and digital image processing technology, but the near-infrared high-pass filtering increase the minimum operating illumination of the system. The paper has made research on the conversion of the minimum illumination in the beyond visual range photoelectric imaging system, and worked out the calculation of the minimum operating illumination under the condition of the actual optical system in the F-number and near-infrared high-pass filter. The paper plays a theory instructed role in the design and analysis of photoelectrical imaging system.