PHASE CONTRAST X-RAY MOCROSCOPE

摘要

The present invention relates to a phase contrast X-ray microscope consisting essentially of a pulsed X-ray source generating an intensive linear beam, an annular condenser to focus the X-ray beam on the object and X-ray optics in the form of a microzone plate to project the object on an X-ray detector. In the rear focal plane of the microzone plate there is a phase ring producing a phase shift in the zero-oder X-radiation from the object in relation to the higher-order radiation from the object structures. The phase shift is determined by the thickness and the material of the phase ring. The condenser may also take the form of an annular mirror for glancing incidence, an annular zone plate or a combination of the two. The phase ring preferably consists of a thin layer of cooper applied to a silicon substrate. The invention provides a good, phase-contrasted image even with X-ray sources with relatively large spatial extension. In addition, interference with the phase contrast image by the zero order of deflection of the zone-plate object lens is prevented by the invention.