工业CT旋转扫描台回转精度对成像质量的影响

The Influence of Rotation Table Rotating Accuracy on Reconstructed Image Quality of Industrial CT

研究旋转扫描台回转精度与工业CT重建图像质量的关系,对选择合适回转精度的旋转扫描台,降低加工成本具有现实意义。通过计算机仿真分析,模拟了旋转扫描台回转偏差分别服从正态分布、偏态分布的情况,采用滤波反投影算法重建了不同回转精度情况下的工业CT图像,并通过数值指标对工业CT重建图像的质量进行了定量评价。仿真结果表明,旋转扫描台的绝对定位精度对工业CT重建图像质量影响较大,而旋转扫描台的重复定位精度对工业CT重建图像质量影响较小。

The study on the influence of rotation table rotating accuracy on reconstructed industrial CT image quality was meaningful to select a suitable rotation table and reduce the processing cost of rotation table. In the simulation, the location errors of rotation table were divided into two types： normal distribution and skew distribution. And the projection data of different accuracy case were reconstructed by filtered back-projection algorithm. In addition, the quality of industrial CT image was ev, aluated by numerical indicators. The simulation results show that the absolute positioning accuracy of rotation table had a strong influence on reconstructed image quality, while the repeated positioning accuracy of rotation table had less effect on the image quality.