从信号检测和人眼视觉角度出发，研究了直视微光夜视系统综合性能评估理论，推导出直视型微光成像系统的MRC（最小可分辨对比度）模型。该模型将光学传递特性与系统信噪比结合，建立了系统直视微光夜视MRC与目标特性、直视微光夜视仪以及人眼各部分参数之间的数学关系。验证结果表明，由该模型得到的系统极限分辨率相较于系统实际测出的分辨率相对误差为3.08%。

The general performance evaluation theory of low light level (LLL) night vision system is studied based on signal detection and human vision. Simultaneously, the minimum resolvable contrast (MRC) model is deduced. Combining the optical transfer properties with the signal-to -noise ratio of system, the mathematical relationship among target characteristic, LLL night vision system and human visual system is established. The simulation result shows that the relative error of the limited sensitivity calculated by MRC model is 3.08 %, compared with the reality of system. The MRC model mentioned in the paper is a more perfect one for evaluating the performance of LLL night vison system.