title: Effects of unresolvable edges in grating-based X-ray differential phase imaging.
abstract: We investigated effects of unresolvable sharp edges on images obtained in a grating-based X-ray differential phase imaging technique. Results of numerical calculations for monochromatic X-rays show that an unresolvable sharp edge generates not only differential-phase contrast but also visibility contrast. The latter shows that the visibility contrast has another major origin other than ultra-small-angle X-ray scattering (USAXS) from randomly distributed unresolvable microstructures, which has been considered the main origin for the contrast. The effects were experimentally confirmed using a synchrotron X-ray source.
authors.forename: Wataru
authors.initials: W
authors.lastname: Yashiro
authors.forename: Atsushi
authors.initials: A
authors.lastname: Momose