Xue Jianwei, Jiang Aimin, Wang Sen, Wang Jingyu, Dai Yanfeng, Dong Zhichao
Appl Opt. 2018 Dec 1;57(34):9936-9943. doi: 10.1364/AO.57.009936.
To increase the spatial resolution while circumventing the problems of increased mass and volume of monolithic telescopes, a Fizeau imaging interferometer testbed (FIIT) with three individual subtelescopes was designed and constructed for high resolution astronomical observation. FIIT is intended to be mounted on a distributed small-satellite constellation with a formation fly configuration; thus the extremely stable pointing of the subtelescopes is the prerequisite for phased imaging, which is because the satellite suffers from some extent of detrimental jitters and drifts needs to be corrected by FIIT itself. FIIT makes use of a shared tip/tilt detection module with a cross-correlation algorithm, three fast-steering mirrors, and closed-loop control technology for pointing correction of three subtelescopes, which can make sure the images are coaligned for a long period of time used to image some faint astronomical objects. This study gives a detailed description of the detection algorithm of image shifts, the hardware design, and data processing flow, followed by closed-loop experiments of a wide-band white light point source. The results of residual errors on the detection camera and the beam-combining camera demonstrate the performance of the pointing correction function, which is a significant milestone for FIIT.
为了在避免单片望远镜质量和体积增加问题的同时提高空间分辨率，设计并建造了一种具有三个独立子望远镜的斐索成像干涉仪试验台（FIIT），用于高分辨率天文观测。FIIT旨在安装在具有编队飞行配置的分布式小卫星星座上；因此，子望远镜的极其稳定指向是相位成像的前提条件，这是因为卫星存在一定程度的有害抖动和漂移，需要由FIIT自身进行校正。FIIT利用具有互相关算法的共享倾斜检测模块、三个快速转向镜以及用于三个子望远镜指向校正的闭环控制技术，这可以确保在长时间用于对一些暗弱天体成像时图像能够对齐。本研究详细描述了图像位移检测算法、硬件设计和数据处理流程，随后进行了宽带白光源的闭环实验。检测相机和光束合成相机上的残余误差结果证明了指向校正功能的性能，这对FIIT来说是一个重要的里程碑。
