Method for compensating for irradiation hardening and scattered beam effects in radiography and X-ray computer tomography

摘要

The method involves recording calibration phantom by using a variety of different angles between a main axis of an ellipse and a central beam of an x-ray receiving unit in a form of caliber scans and x-ray projection images with different acceleration voltages and storing the calibration phantom in a memory of an image processing computer. Volumes of the calibration phantom are reconstructed by inverse radon transformation. Coefficients of a fractional rational function in the calibration phantom associated to a look-up table are stored.