To compare the detection capabilities of traditional infrared imaging systems and infrared polarization imaging systems, the operating distance models of the systems were established based on the minimum resolvable temperature difference and the minimum resolvable polarization degree difference. The effects of parameters of non-ideal detectors on the detection capabilities of the systems were discussed, and the corresponding experiments were designed to verify the reliability of the established models. This provides a reference for the selection of imaging systems in different application scenarios in actual detection.