GEO-ASTRA: a toolbox for non-conventional XCT scanning and reconstruction

Conventional, circular CT scanning is the standard technique for the large majority of applications. Although being wellestablished and widely applicable, the standard approaches can reach practical limits when inspecting specific samples with specific demands (e.g., high resolution imaging on high aspect-ratio samples). Therefore, non-conventional X-ray CT (NCXCT) scanning approaches can have several benefits above traditional circular scanning methods, such as lower set-up cost in an industrial setting, increased spatial resolution capability, faster and/or more focused scanning. In this contribution, we present some applications of GEO-ASTRA, a toolbox for non-conventional XCT scanning and reconstruction. As a major advantage, the toolbox is general, not system specific. We show its capabilities to work with the FleXCT scanner at imec-Vision Lab, featuring 10 degrees of freedom, including source (vertical/horizontal), sample stage (horizontal, axial, forward/backward, centering, rotation), and detector (vertical, horizontal, forward/backward) motions. It has the ability to generate non-conventional scanning scripts and acquire projection data as such, which can be in turn reconstructed using the GEO-ASTRA toolkit, using algebraic and/or analytical reconstruction. We show the general workflow for including specific parameters of the NC-XCT trajectories in ASTRA for the FleXCT system and demonstrate some of the possible scanning geometries and potential industrial applications.