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arXiv · 1509.06656

Development of a fast electromagnetic shutter for compressive sensing imaging in scanning transmission electron microscopy

Abstract

The concept of compressive sensing was recently proposed to significantly reduce the electron dose in scanning transmission electron microscopy (STEM) while still maintaining the main features in the image. Here, an experimental setup based on an electromagnetic shutter placed in the condenser plane of a STEM is proposed. The shutter blanks the beam following a random pattern while the scanning coils are moving the beam in the usual scan pattern. Experimental images at both medium scale and high resolution are acquired and then reconstructed based on a discrete cosine algorithm. The obtained results confirm the predicted usefulness of compressive sensing in experimental STEM even though some remaining artifacts need to be resolved.

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Armand Béché, Bart Goris, Bert Freitag, Jo Verbeeck. 2015-09-22. Development of a fast electromagnetic shutter for compressive sensing imaging in scanning transmission electron microscopy. https://doi.org/10.1063/1.4943086

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