上海天文台1．56米望远镜斑点干涉成像实验进展

斑点干涉成像技术是克服大气湍流影响，提高地面大口径望远镜分辨本领的有效途径之一。该技术利用斑点相机拍摄一系列的短曝光像，使得大气湍流冻结，再经过图像处理获得高分辨率重建像。该技术设备简单，易于实现，很快在观测天文学中得到了广泛的应用，尤其是对双星的研究。首先回顾了天文高分辨率重建技术的发展，并介绍了相关研究成果。描述了几种典型的斑点干涉成像处理方法及其优缺点。对图像噪声类型及滤波方法进行了分析。在上海天文台1．56m望远镜上开展了双星斑点干涉观测实验，目标星等4～7mag，双星目标星等差小于2。分别采用斑点干涉术和迭代位移叠加法成功实现了双星目标的高分辨率成像，初步证明了在1．56m望远镜上进行斑点干涉成像实验，能够达到接近望远镜衍射极限的分辨率水平。

The Progress in Speckle-Imaging Experiment with the 1.56m Telescope of the Shanghai Astronomical Observatory

The speckle-imaging technique is one of effective methods that can largely compensate atmospheric turbulence effects to improve the resolution of a ground-based telescope. The technique utilizes a speckle camera to obtain a series of short-exposure images where the turbulence effects are almost instantaneous, and then reconstruct a high-resolution image by image processing. For its convenient implementation, this technique has been widely used in observational astronomy, especially for observing binary stars. This paper first briefly reviews the development of astronomical high-resolution image reconstruction techniques, by describing research achievements, some typical methods, and the disadvantages of these methods. The paper subsequently describes the type of noise in speckle images and filtering methods. We experiment the technique by observing binary stars with the 1.56m telescope. The object magnitudes are between d and 7, and the magnitude differences in the binary systems are less than 2. The high-resolution images of binary stars are reconstructed successfully with the speckle interferometry and the Iterative Shift-and- Add method. It is shown that the speckle-imaging experiment on the 1.56m telescope has reached the diffraction-limit resolution of the telescope.