Evaluation and correction of readout artifacts from flat panel detectors for non-destructive testing purposes

Flat panel detectors are commonly used for non-destructive testing purposes using X-ray technology. During a series of measurements with high absorbing objects, we observed an unknown kind of artifacts especially apparent with high contrast edges. These artifacts lead to unwanted results in radioscopic and computed tomography inspection. Given the object is fully occupying the lower part and half of the upper part of the detector. Looking at the image with high contrast visualization, it can be seen that the covered upper part of the detector is brighter than the covered lower half. The horizontal border of the detector tile is clearly recognizable. Furthermore, the uncovered area directly above the object is darker than next to the edge. In this area the vertical border of the edge below can be localized. We examined and evaluated the effect and developed a correction algorithm. The effect and its correction results are presented.