A reconstruction method for cone-beam differential x-ray phase-contrast computed tomography

• Published in: Optics express Vol. 20; no. 19; pp. 21512 - 21519
• Main Authors: Fu, Jian, Velroyen, Astrid, Tan, Renbo, Zhang, Junwei, Chen, Liyuan, Tapfer, Arne, Bech, Martin, Pfeiffer, Franz
• Format: Journal Article
• Language: English
• Published: United States 10.09.2012
• Subjects: Algorithms; Atom and Molecular Physics and Optics; Atom- och molekylfysik och optik; Cone-Beam Computed Tomography - methods; Fysik; Natural Sciences; Naturvetenskap; Numerical Analysis, Computer-Assisted; Physical Sciences; Radiographic Image Interpretation, Computer-Assisted - methods; X-Rays
• ISSN: 1094-4087; 1094-4087
• DOI: 10.1364/OE.20.021512

Most existing differential phase-contrast computed tomography (DPC-CT) approaches are based on three kinds of scanning geometries, described by parallel-beam, fan-beam and cone-beam. Due to the potential of compact imaging systems with magnified spatial resolution, cone-beam DPC-CT has attracted significant interest. In this paper, we report a reconstruction method based on a back-projection filtration (BPF) algorithm for cone-beam DPC-CT. Due to the differential nature of phase contrast projections, the algorithm restrains from differentiation of the projection data prior to back-projection, unlike BPF algorithms commonly used for absorption-based CT data. This work comprises a numerical study of the algorithm and its experimental verification using a dataset measured with a three-grating interferometer and a micro-focus x-ray tube source. Moreover, the numerical simulation and experimental results demonstrate that the proposed method can deal with several classes of truncated cone-beam datasets. We believe that this feature is of particular interest for future medical cone-beam phase-contrast CT imaging applications.