红外探测器组件作为目标探测和成像系统的核心器件，其空间分辨能力直接影响着探测系统的成像质量。评估探测器组件空间分辨能力时，常使用调制传递函数(MTF)，而探测器组件的光学串音是影响MTF 的主要因素。介绍了一套弥散斑直径为30 μm 的红外小光点测试系统，采用扫描狭缝法测试不同结构红外探测器组件的线扩展函数(LSF)并建立相应模型进行模拟分析。理论模拟与实验结果一致,可以很好地解释叠层电极结构侧面的光响应产生的LSF展宽、左右不对称和次峰等现象，该结果为红外探测器组件杂光抑制设计提供了参考。

Infrared detector module is the key device of target detection and imaging system and its spatial resolution directly affects the imaging quality of detection system. When evaluating spatial resolution of detector modules, researchers usually adopt modulation transfer function (MTF), which is mainly influenced by the optical crosstalk of detector modules. The basic principle and configuration of infrared micron-spot test system, whose optical dispersion diameter is 30 μm are introduced. The line spread function(LSF)of detectors with different structures is measured by the scanning slit technique, and a corresponding model is built for analysis. Theoretical analysis and numerical simulation agree well with the experimental results, demonstrating that the profile of overlap electric region is photosensitive, which is the main factor to cause widened LSF, asymmetry, secondary peak and so on. The result provides a reference for the design of infrared detector modules to suppress light stray.