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arXiv · 2208.09470

Undersampling Raster Scans in Spectromicroscopy for reduced dose and faster measurements

Oliver Townsend·Silvia Gazzola·Sergey Dolgov·Paul Quinn
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Abstract

Combinations of spectroscopic analysis and microscopic techniques are used across many disciplines of scientific research, including material science, chemistry and biology. X-ray spectromicroscopy, in particular, is a powerful tool used for studying chemical state distributions at the micro and nano scales. With the beam fixed, a specimen is typically rastered through the probe with continuous motion and a range of multimodal data is collected at fixed time intervals. The application of this technique is limited in some areas due to: long scanning times to collect the data, either because of the area/volume under study or the compositional properties of the specimen; and material degradation due to the dose absorbed during the measurement. In this work, we propose a novel approach for reducing the dose and scanning times by undersampling the raster data. This is achieved by skipping rows within scans and reconstructing the x-ray spectromicroscopic measurements using low-rank matrix completion. The new method is robust and allows for x 5-6 reduction in sampling. Experimental results obtained on real data are illustrated.

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Oliver Townsend, Silvia Gazzola, Sergey Dolgov, Paul Quinn. 2022-08-15. Undersampling Raster Scans in Spectromicroscopy for reduced dose and faster measurements. https://doi.org/10.1364/oe.471663

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