Design of UV Annular Imaging System for Atmospheric Limb Detection
ZHANG Jing1,2, WANG Shu-rong1*, LI Bo1, XUE Qing-sheng1, HUANG Yu1
1. Changchun Institute of Optics, Fine Mechanics and Physics，Chinese Academy of Sciences, Changchun 130033, China 2. University of Chinese Academy of Sciences, Beijing 100049, China
Abstract：In order to meet the requirements of imaging the surrounding 360°scene at one time without rotating the optical system and satisfy the UV limb detecting, a panoramic imaging system was presented for atmospheric UV limb detection. First, considering the special working band and innovative application and proceeding from the basic principle of traditional panoramic annular lens, the curvature radius of four spherical surfaces was adjusted, combined with the detector size so that can get the best MTF. Then, based on the aberration theory, the relay lens system was designed to make up the aberration produced by panoramic annular lens. The separation of positive and negative lens combination with different refraction and Abbe number was used. The negative lens used fused silica, while the positive lens used calcium fluoride, so to correct the apochromatism. Finally, the optical system was optimized with CODE-V and the important tolerance parameters were listed, so that the subsequent processing can be requested. The design results show that the diameter of 80% encircled energy of UV panoramic limb imaging system is below 11 μm，which is smaller than the pixel size of CCD, and the MTF value of the system is higher than 0.7@384 mm-1 over all fields. These data satisfy the requirements of the system and prove the feasibility of panoramic imaging system in atmospheric UV limb detection.
Key words：Limb detection;Panoramic annular lens;Relay lens system
