title: Geometric Parameters Estimation and Calibration in Cone-Beam Micro-CT.
abstract: The quality of Computed Tomography (CT) images crucially depends on the precise knowledge of the scanner geometry. Therefore, it is necessary to estimate and calibrate the misalignments before image acquisition. In this paper, a Two-Piece-Ball (TPB) phantom is used to estimate a set of parameters that describe the geometry of a cone-beam CT system. Only multiple projections of the TPB phantom at one position are required, which can avoid the rotation errors when acquiring multi-angle projections. Also, a corresponding algorithm is derived. The performance of the method is evaluated through simulation and experimental data. The results demonstrated that the proposed method is valid and easy to implement. Furthermore, the experimental results from the Micro-CT system demonstrate the ability to reduce artifacts and improve image quality through geometric parameter calibration.
authors.affiliation: State Key Laboratory of Precision Measuring Technology and Instrument, Tianjin University, Tianjin 300072, China. lhjzjt@tju.edu.cn.
authors.forename: Jintao
authors.initials: J
authors.lastname: Zhao
authors.affiliation: State Key Laboratory of Precision Measuring Technology and Instrument, Tianjin University, Tianjin 300072, China. xthu@tju.edu.cn.
authors.forename: Xiaodong
authors.initials: X
authors.lastname: Hu
authors.affiliation: State Key Laboratory of Precision Measuring Technology and Instrument, Tianjin University, Tianjin 300072, China. jingzoutd@tju.edu.cn.
authors.forename: Jing
authors.initials: J
authors.lastname: Zou
authors.affiliation: State Key Laboratory of Precision Measuring Technology and Instrument, Tianjin University, Tianjin 300072, China. xthu@tju.edu.cn.
authors.forename: Xiaotang
authors.initials: X
authors.lastname: Hu
mesh_terms: D000465:Algorithms; D016477:Artifacts; D002138:Calibration; D054893:Cone-Beam Computed Tomography / Q000592:standards*; D007091:Image Processing, Computer-Assisted / Q000379:methods*; D019047:Phantoms, Imaging; D055114:X-Ray Microtomography / Q000592:standards*
keywords: calibration; computed tomography; geometric parameters estimation; misalignment