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Design of dual band imaging system for space debris

In order to detect the space debris, a dual band imaging system for space debris was proposed. The dual band imaging system was consisted of visible imaging system and long-wave imaging system. The dual band imaging system used the primary mirror and secondary mirror together, including correction lens in every imaging system in order to balance aberration. The focal length was 1000 mm and field of view was 1. 2° for visible imaging system, and the focal length was 250 mm and field of view was 2.75° for LWIR imaging system. Some measures were taken to make sure the less degradation of MTF for thermal distortion, such as a kind of material with good thermal property as mirror substrate to reduce surface distortion. The modulation transfer function (MTF) of dual band imaging system in condition of 20± 5°C was analyzed, which showed a good result for user’s requirement.