Lifton Joseph, Liu Tong
Opt Express. 2019 Feb 4;27(3):3217-3228. doi: 10.1364/OE.27.003217.
X-ray computed tomography (XCT) is a well-established method for measuring and inspecting an object's internal structure in a non-destructive manner. Ring artefacts are unwanted high- or low-intensity rings that appear in CT images that influence CT-based measurements. The cause of the subtle ring artefacts found in high-resolution XCT data is found to be due to inadequate flat field detector correction. Therefore, in this work, the usual two-point flat field correction is replaced by a multi-point, piecewise linear flat field correction. The proposed method is shown to increase the signal-to-noise ratio of exemplary CT data by up to 12.1%. Based on the results presented, it is recommended that a minimum of seven open field images should be used for flat field correction.
X射线计算机断层扫描（XCT）是一种成熟的以非破坏性方式测量和检查物体内部结构的方法。环形伪影是出现在CT图像中的不需要的高强度或低强度环，会影响基于CT的测量。发现高分辨率XCT数据中出现的细微环形伪影的原因是平板探测器校正不足。因此，在这项工作中，通常的两点平板校正被多点、分段线性平板校正所取代。所提出的方法显示可将示例性CT数据的信噪比提高多达12.1%。根据所呈现的结果，建议至少使用七张开放视野图像进行平板校正。
