NUMERICAL REMOVAL OF RING ARTIFACTS IN MICROTOMOGRAPHY

Defective and insufficient calibrated detector elements introduce ring or half-circle artifacts in microtomographic image reconstructions. A computationally efficient numerical filter is presented which suppres ses these defects by taking advantage of the particular appearance of ring artifacts in the Fourier transforms of the recorded sinograms. Th e performance of the filter is demonstrated on experimental data taken with high-energy synchrotron radiation in-phase-contrast (outline) mo de. (C) 1998 American Institute of Physics.