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arXiv · 2011.06671

Disassemblable Fieldwork CT Scanner Using a 3D-printed Calibration Phantom

Florian Schiffers·Thomas Bochynek·Andre Aichert·Tobias Würfl·Michael Rubenstein·Oliver Cossairt
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Abstract

The use of computed tomography (CT) imaging has become of increasing interest to academic areas outside of the field of medical imaging and industrial inspection, e.g., to biology and cultural heritage research. The pecularities of these fields, however, sometimes require that objects need to be imaged on-site, e.g., in field-work conditions or in museum collections. Under these circumstances, it is often not possible to use a commercial device and a custom solution is the only viable option. In order to achieve high image quality under adverse conditions, reliable calibration and trajectory reproduction are usually key requirements for any custom CT scanning system. Here, we introduce the construction of a low-cost disassemblable CT scanner that allows calibration even when trajectory reproduction is not possible due to the limitations imposed by the project conditions. Using 3D-printed in-image calibration phantoms, we compute a projection matrix directly from each captured X-ray projection. We describe our method in detail and show successful tomographic reconstructions of several specimen as proof of concept.

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Florian Schiffers, Thomas Bochynek, Andre Aichert, Tobias Würfl, Michael Rubenstein, Oliver Cossairt. 2020-11-12. Disassemblable Fieldwork CT Scanner Using a 3D-printed Calibration Phantom. https://arxiv.org/abs/2011.06671

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