Matched Backprojection Operator for Combined Scanning Transmission Electron Microscopy Tilt- and Focal Series
Matched Backprojection Operator for Combined Scanning Transmission Electron Microscopy Tilt- and Focal Series
复制标题
DOI：
10.1017/s1431927615000525
复制
发表时间：
2015-06-01
影响因子：
2.8
通讯作者：
Slusallek, Philipp
中科院分区：
文献类型：
--
作者：
Dahmen, Tim;Kohr, Holger;Slusallek, Philipp
组合倾斜和聚焦系列扫描透射电子显微镜是最近开发的一种获得薄样品纳米级三维（3D）信息的方法。在本研究中，我们将这种采集方案中的前向投影表述为线性算子，并证明它是平行照明的射线变换的推广。我们分析推导出相应的反投影算子作为正投影的伴随。我们进一步证明，与使用基于启发式加权的反投影的情况相比，匹配的反投影算子极大地提高了迭代 3D 重建的收敛速度。此外，我们还表明 3D 重建的质量更好。
Combined tilt- and focal series scanning transmission electron microscopy is a recently developed method to obtain nanoscale three-dimensional (3D) information of thin specimens. In this study, we formulate the forward projection in this acquisition scheme as a linear operator and prove that it is a generalization of the Ray transform for parallel illumination. We analytically derive the corresponding backprojection operator as the adjoint of the forward projection. We further demonstrate that the matched backprojection operator drastically improves the convergence rate of iterative 3D reconstruction compared to the case where a backprojection based on heuristic weighting is used. In addition, we show that the 3D reconstruction is of better quality.