MOS resistor arrays are widely used and play an important role in infrared simulation field. As the core device in the infrared hardware-in-the-loop simulation link, the imaging effect is directly related to the accuracy and confidence of the final simulation results. At present, a series of problems, such as image degradation and coupling distortion, will occur when the infrared simulation digital signal enters the MOS resistor array. Therefore, it is necessary to analyze the imaging principle and energy transfer process of the MOS resistor array based on its imaging mechanism, and to establish a process and radiation model for a single pixel which conforms to its own physical characteristics. The accuracy and confidence of the model were quantified and verified by the functional relationship between the input signal and the output signal. These achievements could provide an important theoretical basis for future research on coupling characteristics, reverse correction models and non-uniformity correction of larger scale MOS resistor arrays, while having significant value in practical engineering applications.