Design of ultra-wide FOV LWIR staring imaging system

In the field of infrared detection, to pursue the full-space inclusion and full-time domain information acquisition of infrared target detection, the ultra-wide field of view (FOV) infrared staring imaging technology came into being. However, limited to objective factors such as fewer infrared band materials, difficulty in aberration correction, and the limited number of optical elements, the design of ultra-wide FOV infrared staring imaging system, especially the 180°FOV, has always been difficult for optical system design. To this end, based on the theory of non-similar equidistant projection imaging, with the reversed telephoto lens optical structure as the initial structure and the uncooled long-wave infrared focal plane detector with a pixel size of 800 × 600 and a pixel dimension of 17 μm × 17 μm as the imaging device, an ultra-wide FOV infrared staring imaging system working at 8–14 μm, F# of 1.0 and staring FOV of 181°is designed and developed by using the hybrid design idea of aspheric surface and spherical surface. The results show that the key indicators of actual system fit well with that of the design result, and the system has a simple structure (only four lenses), good image plane uniformity (≥ 88%), high imaging quality (MTF > 0.4 of the edge FOV), and small distortion (< 4%), which can meet the design requirements of engineering applications.