Abstract:Wavefront coding modulates the beam by a phase mask with a specially designed surface type, the depth of field is extended and the optical system is insensible to defocus consequently. Then the intermediate blurred image can be turned into a clear image by digital image processing, achieving athermalization. In this paper, wavefront coding is applied on athermalization of a long wave infrared optical system, comparing the point spread function, the modulation transfer function, the image simulation and the tolerance of the wavefront coding system with those of the original optical system. The results show that wavefront coding technology can provide a price competitive athermalization solution for the infrared imaging system, making the system has a good and stable performance in a temperature range of -40℃ to 60℃.