NUMERICAL RECONSTRUCTION METHOD FOR HIGHER SPATIAL RESOLUTION IN ELECTRON HOLOGRAPHY

电子全息术中更高空间分辨率的数值重建方法

• 批准号: 04650038
• 负责人: OHSHITA Akinori
• 金额: $ 1.28万
• 依托单位: MIE UNIVERSITY
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for General Scientific Research (C)
• 财政年份: 1992
• 资助国家: 日本
• 起止时间: 1992 至 1993
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/en/grant/KAKENHI-PROJECT-04650038/
• 关键词: Electron Holography; Numerical Reconstruction; Spatial Carrier Frequency; Phase Image; Thase Image; Interfarence Electron Microscopy; バイプリズム干渉縞; フレネル回折縞

To reconstruct a wave from an off-axis image hologram by an ordinary method using the Fourier transform, the carrier fringes should be less than one third of the required resolution. A new numerical reconstruction method is proposed which can be applied even when the carrier frequency does not satisfy this condition.1. By averaging the intensity distribution of the electron hologram in the direction perpendicular to the biprism interference fringes, the incoherent intensity distribution which loses those fringes is produced numerically.2. Subtaction between these two intensity distributions allows the reconstructed images to consist of spatial frequency as high as carrier frequency of the hologram.3. The method is simpler than that proposed by Harada and Shimizu.

要用傅里叶变换从离轴像全息图中再现波，载流子条纹应小于所需分辨率的三分之一。提出了一种新的数值重建方法，该方法即使在载波频率不满足这一条件的情况下也能适用。通过对电子全息图垂直于双棱镜干涉条纹方向的光强分布进行平均，得到了失去双棱镜干涉条纹的非相干光强分布。这两个强度分布之间的减法允许重建图像由与全息载波频率一样高的空间频率组成。该方法比Harada和Shimizu提出的方法简单。