Near-Earth space balloon-based multi-band airglow imager optic design

As a common tracer in the atmosphere, airglow can be used as an important means to study the interaction between the lower atmosphere, near space, and ionosphere. In the near-Earth space, the high-altitude balloon can realize long time flight, which makes the airglow detection realize both high range resolution and time resolution. In this paper, a balloon-based multi-band airglow imager is designed, which can observe OI (557.7 nm), Na (589.3 nm), OI (630.0 nm), and OH (720-910 nm) with annular field of view (30° inner ring and 80° outer ring), and its resolution is 500 m at 250 km. The multi-band airglow imager designed in this paper is equipped in the payload cabin and raised to above 30 km for flat flying for more than 6 h. The experimental results show that the imager worked normally, and airglow images were photographed and stored; the optical system can stand the harsh environment in the near space. The multi-band airglow imager designed in this paper will take part in other near-space exploration tasks in the future and obtain corresponding results.