Abstract Theoretical analyses of x-ray diffraction phase contrast imaging and near field phase retrieval method are presented. A new variant of the near field intensity distribution is derived with the optimal phase imaging distance and spatial frequency of object taken into account. Numerical examples of phase retrieval using simulated data are also given. On the above basis, the influence of detecting distance and polychroism of radiation on the phase contrast image and the retrieved phase distribution are discussed. The present results should be useful in the practical application of in-line phase contrast imaging.
Received: 02 July 2004
Revised: 29 November 2004
Accepted manuscript online:
PACS:
07.85.-m
(X- and γ-ray instruments)
Fund: Project supported by the National Natural Science Foundation of China (Grant No 60278030)
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