In this study, an analyzer assembly suitable for developing a midwave infrared thermal imaging camera is designed to improve the speed of traditional time-sharing infrared polarization imaging. Further, the model of the mid-wave infrared thermal imaging camera is converted into a midwave infrared polarization imaging device to obtain the infrared polarization information of the target scene. This device uses a motor to ensure that the infrared polarizer can rotate at a uniform speed of 900 r/min and collects infrared intensity images in different polarization directions. A single pixel non-uniform differential image correction method is used to remove the cold reflection of infrared images, and the iterative sorting method is used to process an image with the corrected infrared intensity. In addition, based on the constructed Stokes vector model, computing the adjacent three consecutive intensity of infrared image of the infrared polarization and polarization angle, assurance and the intensity of the infrared image has the same imaging frame frequency. Experiment results show that the aforementioned device can achieve stable output of the infrared polarization degree and polarization angle with respect to the target to be measured. The frame frequency of the output infrared polarization image is 45 frame/s, which is in accordance with the real-time infrared polarization requirements for moving target detection.