从探测器的响应特性、光学系统的相对辐射和外壳的杂散光三个方面对红外成像传感器系统非均匀性的产生原因进行了理论研究。红外焦平面阵列中，探测元与探测元间的结构及材料差异会影响量子效率及暗电流，从而影响探测元的响应特性。光学系统主要通过光瞳畸变矩阵影响场景辐射通量的分布，光学系统本身的辐射对非均匀性的贡献可以忽略。外壳的杂散光可分为高温部分和低温部分，忽略低温部分，引入系统冷屏效率的概念，建立了高温组件的辐射模型。该理论研究对光学系统的设计及非均匀性校正具有一定的参考意义。

The causes for nonuniformity of infrared imaging systems are theoretically studied in the following three aspects: the response characteristics of detectors, the relative radiation of optical systems and the stray light from system housings. In an Infrared Focal Plane Array (IRFPA), the difference of structures and materials of detection elements may affect their quantum efficiency and dark current and hence affect their response characteristics. The optical system mainly affects thescene flux distribution through its pupil distortion matrix. The contribution of the radiation from the optical system itself to the nonuniformity can be ignored. The stray light from the housing can be divided into the high temperature part and the low temperature part. By ignoring the low temperature part and introducing the concept of System Cold Shield Efficiency (SCSE), a high temperature component radiation model is established. This theoretical research is of a certain referential value to the design and nonuniformity correction of optical systems.