ABSTRACT

This chapter considers the collection of sparse samples in electron microscopy, either by modification of the sampling methods utilized on existing microscopes, or with new microscope concepts that are specifically designed and optimized for collection of sparse samples. It explores potential embodiments of a multi-beam compressive sensing electron microscope. Sparse measurement matrices offer an advantage of efficient image recovery, since each iteration of the process becomes a simple multiplication by a sparse matrix. Electron microscopy is well suited to compressed or sparse sampling due to the difficulty of building electron microscopes that can accurately record more than one electron signal at a time. Sparse sampling in electron microscopy has been considered for dose reduction, improving three-dimensional reconstructions and accelerating data acquisition. For sparse sampling, variations of scanning transmission electron microscopy (STEM) are typically used. In STEM, the electron probe is scanned across the specimen, and the detector measurement is recorded as a function of probe location.