A Review of Computed Laminography Technology: Principle, Artifact Suppression, and Applications

Industrial X-ray 3D imaging is an advanced non-destructive testing method, it through the X-ray penetration of the object under test and obtain projection data, and then through the computer reconstruction algorithms to generate three-dimensional images of the internal structure of the object for detection. Computed Tomography (CT) is an important and mature branch of industrial X-ray three-dimensional imaging technology, but there are certain defects when applied to flat objects imaging. Computerized Laminography (CL) is a high-resolution 3D imaging technique for large-size, flat objects. Due to differences in geometric scanning shapes compared to CT scans, geometric parameter errors and incomplete projection information can lead to complex geometric artifacts and aliasing artifacts during reconstruction, affecting the accuracy of industrial inspection results. This paper combines the relevant principles and technological advances of CT imaging methods with CL imaging methods as the main object of the review, firstly, systematically describes the different geometrical scanning modes and the corresponding 3D reconstruction principles of industrial X-ray imaging methods，summarizing the impact of system hardware parameters on reconstruction in imaging methods; secondly, summarizes and explores the mechanism of geometrical artifacts and interlayer aliasing artifacts in the process of 3D reconstruction as well as the related artifact suppression key technologies; and then provides specific application scenarios, advantages and disadvantages of the CT and CL technologies. The specific application scenarios, advantages and disadvantages of CT and CL technologies are analyzed; finally, by summarizing the current research and application status of CT and CL imaging methods, future research focuses and difficulties are put forward to provide references for the development and in-depth research of this technology.