Abstract: The working principle of an extended infrared optical system was introduced in this paper. Because the imaging is usually affected by the deviation of view field due to the assembly error of wedge lens after initialization of system, a new infrared imaging optical measuring method was put forward in order to check the deviation of view field in optical system. The method integrated infrared imaging system and the computer vision technology that was applied in measuring the trajectory of motion target. The infrared imaging system was used to image the motion targets. Then the trajectories of motion target were regarded as the sequence of discrete points. The computer vision technology was used to detect the trajectories of the points and collect the image of discrete points in the continuous motion of those targets. Later, the deviation of view field of extended infrared optical system was revised by image processing of the original image of the trajectory of motion target and simulation of actual trajectory of motion target using programming. The results show that the infrared imaging measuring system which is based on computer vision technology can efficiently complete the measuring of the trajectory of motion target.