Design of a Wide Field of View LWIR Optics using Single Layer Diffractive Optical Element

Visual UAV navigation requires high resolution cameras with wide field-of-view to attain better feature matching in acquired imagery. The designing of WFOV optics for large-array LWIR sensors presents a unique set of challenges in attaining optimum optical performance with fewer number of optical components without incorporating active athermalization. This article presents design of 84° × 67° FOV optics for 1280 x1024 LWIR microbolometer with MTF of ≥ 0.6 at 20 lp/mm and limiting barrel distortion to less than or equal to 20%. The design is comprised of only three lenses with one single-layer DOE. The design is low-SWaP solution with improved optical performance.