Refrigeration Mwir Staring Zoom Optical System

In military applications, infrared imaging and infrared-guided have presented a remarkable capacity. Infrared zoom systems can not only meet the demands of searching at wide field and target tracking at narrow field, but also solve the problem of losing the rapid moving target in a short period of time due to the field shift between dual field-of-view and multi-field-of-view. As the detection degree of cooling-detector detection is 1 to 2 orders of magnitude higher than normal detectors, most of the high-resolution infrared imaging system requires refrigeration. Meanwhile, the cooled infrared zoom system has to take into consideration the quality of image, and other factors such as the narcissus, cold shielding efficiency, and athermalization, which have no doubt increased the difficulty of optical design.This thesis at first reviewed both international and domestic development of infrared zoom system, and introduced the peculiarity of infrared optical system. Then it focused on the basic concepts and basic types of the zoom system, namely the positive group compensation and the negative group compensation, which were analyzed with the Gaussian theory and programmed and calculated through Excel. After that, it gave the definition and the generating conditions of the narcissus, and pointed out that the YNI and the I / Ibar were greater than 1 was fully non-essential conditions. Thereafter, this thesis analyzed the three forms of athermalization design and made a comparison of their advantages and disadvantages respectively.Finally, combining the knowledge introduced by previous chapters, it calculated two initialization forms of zoom system by using Excel, that is to say a positive compensation group whose zoom curves skip from one to another and a negative compensation group whose variable power group magnification from the positive infinite Skip to the negative infinite. And the image quality of both was improved through Code v program. Afterwards, having corrected the image quality, the first infrared zoom system was put through narcissus and athermalization analysis, and then the final curve of the zoom was drawn out.