WIDE FIELD OF VIEW MONOCENTRIC LENS AND IMAGE SENSOR SYSTEM FOR INFRARED AERIAL RECONNAISSANCE CAMERA SYSTEMS

摘要

Wide field of view optical systems are disclosed for an infrared aerial reconnaissance camera. The optical systems include a curved focal surface and a wide field of view monocentric lens system. The monocentric lens system includes front and rear lens shell elements and a core lens element, with the number of front and rear shell lens elements depending on the IR band of interest (LWIR, MWIR or SWIR). Infrared radiation entering the monocentric lens passes sequentially through the front shell lens element(s), the core lens element, and the rear shell lens element(s) and is focused onto the curved focal surface. The front shell lens element(s) and the rear shell lens element(s) are made of material having a relatively higher refractive index or a relatively higher optical dispersion, or both, in the band of interest, as compared to the core lens element. The materials are carefully selected to minimize chromatic and spherical aberration as well as secondary chromatic aberration and spherochromatism, and pass radiation in the band of interest. The core lens element is made from a material having a relatively lower refractive index or a relatively lower optical dispersion or both, in the band of interest, and is carefully selected to compensate for spherical and chromatic aberration as well as secondary chromatic aberration and spherochromatism.