Patent ID: 6925140

Claim:
A method for correcting for stray radiation in an X-ray computed tomography scanner comprising the steps of: irradiating a detector arrangement, composed of a multiplicity of detector elements arranged next to each other in a plurality of adjacent detector rows, with X-rays in a tomography measuring field of a computed tomography scanner; from each of said detector elements, obtaining a measured intensity value representing an intensity of X-rays incident thereon; obtaining at least one reference distribution of stray radiation intensity in a row direction of said detector arrangement and, for each of said measured intensity values, determining a stray radiation component thereof dependent on said at least one reference distribution; and for at least some of said detector rows, correcting the respective measured intensity values of the detector elements thereof as a function of the respective stray radiation components of those measured intensity values by recursion, including the steps of: determining the respective stray radiation components of the measured intensity values of the detector elements in a current row in said recursion from the respective measured intensity values of the detector elements of said current detector row, and respective primary radiation components of the respective measured intensity values of detector elements of a preceding detector row in said recursion, determining said respective primary radiation components of the measured intensity values of the detector elements of said preceding detector row from measured intensity values of said detector elements of said preceding detector row and the respective stray radiation components of said measured intensity values of the detector elements of said preceding detector row, and using intensity values from said reference distribution as the respective stray radiation components of the measured intensity values of detector elements of a first detector row in said recursion.