Beam hardening-respecting flat field correction of digital X-ray detectors

Inter-pixel sensitivity variations in the X-ray flat panel detector give rise to gain non-uniformity. These artifacts degrade the quality of digital radiography and fluoroscopy imaging. The state-of-the-art gain correction methods are analyzed and found to be inadequate in dealing with beam hardening-related non-uniformity. We have developed a multi-dimensional signal model to accommodate the beam hardening related factors in practical scenarios. A novel beam hardening-respecting (BHR) gain correction method is devised for medical X-ray flat panel detectors. Improvements of the proposed technique over fixed point and variable gain correction are demonstrated.