Accuracy Evaluation and Exploration of Measurement Uncertainty for Exact Helical Cone Beam Reconstruction Using Katsevich Filtered Back-projection in Comparison to Circular Feldkamp Reconstruction with Respect to Industrial CT Metrology

摘要

New requirements to scan long objects are fostering the use of helical scan trajectories. An exact filtered back-projection-based method has been suggested by Katsevich. In this paper, we investigate the applicability of this reconstruction strategy in industrial CT vs. conventional filtered back-projection type reconstructions. Hereby, we study the accuracy and the measurement uncertainty in terms of length and form deviations by using a circular and helical scans of a calibrated cube with spherical caps. The results show that Katsevich's helical algorithm can theoretically lead to more accurate measurements than circular FDK, but that it requires a more precise calibration during data acquisition.