Design Of Infrared Zoom System

IR zoom system has been widely used in many fields, and become an important branch in IR technology research. IR system has some advantages over visible light system. The environment affects the performance of IR optical system a lot, causing the attenuation of the intensity of IR light by its absorbing. In this paper the operating distance is determined based on the analysis of IR feature of targets and IR transmission and emission of the atmosphere.On the basis of the theory of visible light zoom system design, the method of designing IR zoom systems is presented .As an example of mechanically compensate zoom lenses is designed. A computer program designed for Gauss optical analyses of zoom system. The track of the moving parts, the variation in the magnification and other Gaussian characters of the zoom system can all be determined with the program. A program for IR zoom system based on a given IR detector is also designed. Moreover, the parameters of the lens are calculated, and then an IR zoom camera is developed with mechanical compensated method, with good performance. The analysis of the Spot diagram and MTF (modulation transfer function) show that the IR zoom system can meet the requirement of practical application.