摘要
目的 探讨探测器响应效率不一致导致重建图像中产生伪迹为环形的过程 ,以及在平行束二维CT、扇束二维 CT中的不同表现 .方法 从 CT图像重建原理入手 ,运用反投影的物理意义 .结果 环形伪迹与射线源旋转角度范围及响应不一致单元在探测器的位置密切相关 .结论 平行束二维 CT产生的伪迹为半环形 ,而扇形束二维 CT产生的伪迹为闭环形 .
Aim\ To research how the non-uniformity in the response of detector elements causes ring artifacts and their different appearance in parallel-beam 2D CT and in fan-beam CT. Methods\ Based on the principle of image reconstruction and the physical meaning of back-projection,the simulation is used. Results\ The ring artifacts are closely related to the angle range of x-ray source, as well as the position of the odd elements with abnormal response. Conclusion\ Artifacts in parallel-beam CT are actually semi-annualar artifacts while those in fan-beam CT are a series of whole-rings.
出处
《华北工学院学报》
2001年第1期16-19,共4页
Journal of North China Institute of Technology
基金
部级“九五”重点预研项目
关键词
计算机断层扫描
环形伪迹
图像重建
CT
无损检测
computer tomography
ring artifacts
image reconstruction
CT
non-destructive tests
