In order to reduce artifacts on industrial computed tomography(CT) images, one method for measuring the projection position of the focal point based on space geometrical relations was put forward. Computer simulations and experiments were carried out. The method established analytic equations between the projection position of the focal point and the projection position of the center of rotation. The projection position of the focal point was calculated through several times calculation of the center of rotation in different places. The method required the turntable to have three freedoms: rotating, moving parallel to the detector and moving vertical to the detector. Computer simulations and experiments results demonstrate that this method is effective to reduce CT artifacts. Compared with the current methods, the proposed algorithm need not any special phantoms and need not any priori geometry parameters. It is more convenient for engineering.
�ų���,��־ƽ,����,��.��ҵCT������ԭ��\[M].����:��ѧ������,2009:3-10 Zhang Chaozong,Guo Zhiping,Zhang Peng,et al.Technique and principle of industrial CT[M].Beijing:Science Press,2009:3-10(in Chinese)
��ȫ��.X���߹�ҵCT�����Ż��о�\ .����:�������պ����ѧ��е���̼��Զ���ѧԺ,2006 Zhang Quanhong.Optimization research on X-ray industrial CT imaging .Beijing:School of Mechanical Engineering and Automation,Beijing University of Aeronautics and Astronautics,2006(in Chinese)
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