METHOD, STORAGE MEDIUM AND IMAGING SYSTEM FOR NONLINEAR PROCESSING FOR OFF-AXIS FREQUENCY REDUCTION IN DEMODULATION OF TWO DIMENSIONAL FRINGE PATTERNS

摘要

PROBLEM TO BE SOLVED: To provide a method of suppressing off-axis fringes in demodulation from single fringe patterns produced by an X-ray Talbot interferometer.SOLUTION: A captured image comprises a phase modulated fringe pattern comprising cross-term phase components. Parameters of at least a first non-linear transformation (h) are determined for attenuating the cross-term phase components. The parameters of the first non-linear transformation are determined for an imaging system to reduce artefacts in a demodulated image introduced by the cross-term phase components. The captured image is demodulated 430 by applying 420 at least the first non-linear transformation with the determined parameters to the captured image to attenuate the cross-term phase components.SELECTED DRAWING: Figure 4