Affiliations: National Digital Switching System Engineering and
Technology Research Center, Zhengzhou, Henan, China
Note: [] Corresponding author: Bin Yan, National Digital Switching System
Engineering and Technology Research Center, Zhengzhou 450002, Henan, China.
E-mail: tom.yan@gmail.com
Abstract: In helical cone-beam industrial computed tomography (ICT), the
reconstructed images may be interfered by geometry artifacts due to the
presence of mechanical misalignments. To obtain artifact-free reconstruction
images, a practical geometric calibration method for helical scan is
investigated based on Noo's analytic geometric calibration method for circular
scan. The presented method is implemented by first dividing the whole ascending
path of helical scan into several pieces, then acquiring the projections of a
dedicated calibration phantom in circular scan at each section point, of which
geometry parameters are calculated using Noo's analytic method. At last, the
geometry parameters of each projection in a piece can be calculated by those of
the two end points of the piece. We performed numerical simulations and real
data experiments to study the performance of the presented method. The
experimental results indicated that the method can obtain high-precision
geometry parameters of helical scan and give satisfactory reconstruction images.
