Random Beam Scanning Transmission Electron Microscopy and Compressive Sensing as Tools for Drastic Electron Dose Reduction in Electron Tomography

Abstract

Electron tomography is a fantastic tool for deciphering the structural information of complex 3D samples. During the last years, several tools have been developped to improve the 3D reconstruction quality of thick specimens. The direct detector cameras have incredibly increased the SNR and resolution of thin samples 2D projections, bringing electron microscopy resolution at the level of the one of X‐ray diffraction studies. However, the study of thick biological samples in tomography still suffers from the too important electron dose one has to use in order to retrieve high quality images and reconstructions. It has been shown that STEM tomography can generate more accurate reconstructions than TEM tomography while preserving better the sample integrity. Previous uses of compressive sensing enabled the reduction of tilt‐angles in tomography studies, unveiling electron dose reduction. Here, we push further the electron dose reduction thanks to a more effective compressive sensing method which uses incomplete images as incoherent data. The generation of incomplete images being performed at the microscope during the acquisition process where the beam randomly scans the surface of the sample.