用空间域相减法提高电子全息图再现像的分辨率

研究了在数字电子全息记录和再现过程中利用空间域相减法消除自相关项影响的实验和数据处理方法。通过适当改变电子棱镜的电压实现同一样品的离轴电子全息图和像强度分布图的实验记录；在图像相减的数据处理过程中，同时使零级衍射谱的总能量趋于最小值的迭代算法来消除记录过程中全息图和像强度图之间可能存在的能量和位置偏差。给出了有关的实验和数据处理结果。实验结果表明，该方法是可行的。

Resolving Power Improvement in Reconstruction of Electron Holograms by Use of Spatial Subtraction Method

An experimental and digital procesing method for eliminating the influences of the autocorrelation item on the reconstructed image of an electron hologram by use of a spatial subtraction was described.In this method,two images were involved.One was recorded when a high voltage was put on the electron biprism and another was recorded after the voltage of the electron biprism returned to zero.For eliminating the energy and location deviation between the two-recorded patterns an iterative algorithm was adopted,in which the total energy of the zero diffraction order was taken as the criterion.The experimental results verified the feasibility of this method.