【摘要】 为了抑制工业计算机层析成像(CT,Computed Tomography)过程中的重建伪影,研究了一种基于空间解析几何关系的射线源焦点投影位置测量方法,并完成了计算机仿真和实验验证.该方法根据工业CT扫描系统的几何结构关系建立射线源焦点投影位置和转台旋转中心投影位置之间的空间解析表达式,然后通过测量转台旋转中心在多个位置的投影来解析求解射线源焦点投影位置.该方法要求转台具有3个自由度:旋转,平行于探测器方向移动,和垂直于探测器方向移动.仿真和实验结果表明,该方法能够有效抑制重建伪影.该方法无需使用特殊模体,不需要任何先验几何参数,较现有方法更为方便.更多还原

【Abstract】 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.更多还原