Operation of a separated-type x-ray interferometer for phase-contrast x-ray imaging

Aiming at large-area phase-contrast x-ray imaging, a separated-type x-ray i nterferometer system was designed and developed to produce 25 x 20 mm inter ference patterns. The skew-symmetric optical system was adopted because of the feasibility of alignment. The rotation between the separated crystal bl ocks was controlled within a drift of 0.06 nrad using a feedback positionin g system. This interferometer generated a 25 x 15 mm interference pattern w ith 0.07 nm synchrotron x-rays. A slice of a rabbit's kidney was observed, and its tubular structure could be revealed in a measured phase map. (C) 19 99 American Institute of Physics. [S0034-6748(99)05112-6].