摘要
由于大气湍流的影响,以及各国深空探测脚步的加快,地基光学望远镜获得衍射极限图像的技术受到国内外天文研究人员的高度重视。幸运成像技术是通过对目标序列短曝光图像数据进行获取、像质评价、图像帧选取、图像配准与叠加、图像增强几个步骤,最终得到一幅清晰度显著提高、视觉效果大大改善的图像。该方法能够有效降低了噪声和大气湍流导致的图像模糊,提高非等晕条件下地基天文望远镜的成像分辨率。本文首先介绍了幸运成像技术的相关基础理论,阐述了大气湍流的特性和非等晕条件下幸运短曝光图像出现的概率,以及EMCCD的相关性能指标,从而为幸运成像技术的研究提供理论基础;然后介绍了幸运成像技术的数据处理流程,讨论了该处理方法的关键技术和需要研究的几个主要问题,并给出了相应的解决方法;最后应用该项技术,设计进行了双星观测成像的实验,并对实验数据进行了事后处理。通过分析处理结果表明,幸运成像技术能够提高目标通过湍流大气的成像分辨率,此项研究为幸运成像技术在深空探测中广泛应用打下了基础。
With the effects of the atmospheric turbulence and the faster steps of the deep-space exploration, obtaining diffraction limited images of astronomical optical telescope becomes more and more fashionable. Lucy imaging technology appeared under this background. Lucy imaging technology finally gains a image that is clearer, more comfortable for vision, passing through the following steps—image acquisition, image quality evaluation, frame selection, image match and adding, image enhancement. This technique has a few advantages:not only effectively reducing the noise and image penumbra arosed by the atmosphere, but also improve the image resolution of ground-based telescope. This thesis introduces a series of problems. Firstly, some basic theory related to the Lucy imaging. Secondly, the data processing flow chart of Lucy imaging. Third, key problems and the corresponding resolution are showed. At last, explain the whole process of binary stars observing, and the significative analysis. Lucy imaging technology has laid a basis for further extending objects in the field of deep-space and other fields.
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