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arXiv · 2102.08650

Phase-contrast THz-CT for non-destructive testing

Peter Fosodeder·Simon Hubmer·Alexander Ploier·Ronny Ramlau·Sandrine van Frank·Christian Rankl
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Abstract

A new approach for image reconstruction in THz computed tomography (THz-CT) is presented. Based on a geometrical optics model containing the THz signal amplitude and phase, a novel algorithm for extracting an average phase from the measured THz signals is derived. Applying the algorithm results in a phase-contrast sinogram, which is further used for image reconstruction. For experimental validation, a fast THz time-domain spectrometer (THz-TDS) in transmission geometry is employed, enabling CT measurements within several minutes. Quantitative evaluation of reconstructed 3D printed plastic profiles reveals the potential of our approach in non-destructive testing of plastic profiles.

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Peter Fosodeder, Simon Hubmer, Alexander Ploier, Ronny Ramlau, Sandrine van Frank, Christian Rankl. 2021-02-17. Phase-contrast THz-CT for non-destructive testing. https://doi.org/10.1364/oe.422961

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