journal article·2026-05-12Open access

Robust electron counting for direct electron detectors with the Back-propagation counting method

Joshua Renner, Matthew A. Wright, Kristofer Bouchard, Bruce E. Cohen, Peter Ercius, Azriel Goldschmidt, Cassio C. S. Pedroso, Ambarneil Saha, Peter Denes

npj Computational Materials· Volume 12· Issue 1

Abstract

Electron microscopy (EM) is a foundational tool for directly assessing the structure of materials. Recent advances in direct electron detectors have improved signal-to noise ratios via single-electron counting. However, accurately counting electrons at high flux remains challenging. We developed a new method of electron counting for direct electron detectors, Back-Propagation Counting (BPC). BPC uses machine learning techniques designed for mathematical operations on large tensors but does not require large training datasets. In synthetic data, we show BPC is able to count multiple electron strikes per pixel and is robust to increasing occupancy. In experimental data, frames counted with BPC are shown to reconstruct diffraction peaks corresponding to individual nanoparticles with relatively higher intensity and produce images with improved contrast when compared to a standard counting method. Together, these results show that BPC excels in experiments where pixels see a high flux of electron irradiation such as in situ TEM movies and diffraction.
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Research context

OpenAlex topics: Advanced Electron Microscopy Techniques and Applications · Electron and X-Ray Spectroscopy Techniques · Advancements in Photolithography Techniques

SciVX discovery tags are terminology-based. OpenAlex topics are source-provided classifications.

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