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大气湍流等动态波前扰动限制大型望远镜的分辨能力，是从有望远镜以来几百年的老问题，自适应光学技术提供了解决这一问题的途径。但对星体目标来说由于所能利用的光能极为有限，动态扰动的时间－空间特性又对系统提出很高要求，因而难度很大。本文报导我们用２１单元自适应光学系统在云南天文台１．２ｍ望远镜上对星体目标进行的首次试验。介绍了针对弱光动态目标的特点对系统的改进。实验结果表明了这一自适应光学系统可以在光子计数率低达９５计数／（子孔径、积分时间）下工作，它对减少象斑弥散和漂移，改善分辨能力，增加星象对比度有显著效果。
Atmospheric turbulence and other dynamic wavefront disturbances that limit the resolving power of large telescopes are a few hundred years old from telescopes. Adaptive optics provide a solution to this problem. However, due to the extremely limited light energy available to the astral target, the time-space characteristics of the dynamic perturbation place high demands on the system and are therefore very difficult. This article reports our first experiment on astral targets using a 21-element adaptive optics system at the Yunnan Observatory’s 1.2m telescope. The improvement of the system is introduced according to the characteristics of weak light dynamic target. The experimental results show that this adaptive optics system can work at photon counting rate as low as 95 counts / (subaperture, integral time), which has significant effect on reducing the dispersal and drift of image spots, improving resolution and increasing the contrast of astrology.