Improving Limited Angle x-ray computed Tomography by Optical data integration - ILATO

X射线计算机层析成像(CT)为样品内部和外部结构的成像、检查和计量提供了一种非破坏性的方法。在经典的锥束CT中，样品在X射线管的锥形射束中以小角度步长旋转360°。对于每个角度台阶，样品的X射线吸收图像由与X射线源和转台对准的X射线探测器记录。对于基本上偏离圆对称的样品，在一组旋转角下，传输的X射线辐射的强度通常是不够的，或者样品不适合锥形束。此外，对于这些样品，可实现的空间分辨率很低，因为样品必须在距离X射线源很远的地方移动。因此，有人建议将扫描程序改名为“有限角度CT”，即只记录有限数量的投影。由于信息有限，不同样品的测量精度差别很大。

X-ray computed tomography (CT) offers a non-destructive method for the imaging, inspection and metrology of interior and exterior structures of a specimen. In classical cone-beam CT, the specimen is rotated by 360° in small angle steps in the cone-shaped beam of an X-ray tube. For each angular step, an X-ray absorption image of the specimen is recorded by an X-ray detector aligned with the X-ray source and the rotation table. For specimens deviating substantially from circular symmetry, at a set of rotation angles, the intensity of the transmitted X-ray radiation is often insufficient or the specimen does not fit inside the cone beam. Furthermore, for these samples, the achievable spatial resolution is low, because the specimen has to be moved at a large distance from the X-ray source. Therefore, modified scan procedures under the name “limited angle CT” have been suggested, where only a limited number of projections is recorded. Due to the limited information, the accuracy of the measurement varies significantly over the specimen.