Authors
KM Pavlov, DM Paganin, S Berujon et al
Lab
School of Physics and Astronomy, Monash University, Victoria 3800, Australia
Journal
arXiv
Abstract
We develop a means for speckle-based phase imaging of the projected thickness of a single-material object, under the assumption of illumination by spatially random time-independent x-ray speckles. These speckles are generated by passing x rays through a suitable spatially random mask. The method makes use of a single image obtained in the presence of the object, which serves to deform the illuminating speckle Þeld relative to a reference speckle Þeld (which need only be measured once) obtained in the presence of the mask and the absence of the object. The method implicitly rather than explicitly tracks speckles, and utilizes the transport-of-intensity equation to give a closed-form solution to the inverse problem of determining the complex transmission function of the object. Application to x-ray synchrotron data shows the method to be robust and e_cient with respect to noise. Applications include x-ray phaseÐamplitude radiography and tomography, as well as timedependent imaging of dynamic and radiation-sensitive samples using low-ßux sources.
BIOSEB Instruments Used:
Aron Test or Four Plates Test (LE830),Rotarod (BX-ROD)