An Efficient Image Distortion Correction Method for an X-ray Digital Tomosynthesis System
Among X-ray cross-sectional imaging methods, digital tomosynthesis (DT) is very useful to PCB inspection because it can obtain a cross-sectional image of a local inspection area quickly. The image intensifier, which is usually used in DT systems, distorts X-ray images in shape and intensity. Therefore, image distortion correction is one of the most important issues in realizing a DT system. This paper presents an image distortion correction method to acquire an arbitrary cross-sectional image of an object by using a distance ratio function in an X-ray DT system. The method uses a simplified distortion model made by a distance ratio function in intensity correction, and by the 2D point mapping polynomials in shape correction.
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