Patent ID: 8972191
Filing Date: 2015-03-03
Classification: A61B,G01N

Abstract:
1. An imaging set-up for reverse projection to obtain quantitative X-ray images from a sample and to quantitatively extract both absorption and phase information from the sample, the imaging set-up comprising: an X-ray source generating an X-ray beam; gratings including a beam splitter grating and an analyzer grating having their respective lines parallel to each other, said beam splitter grating being a phase grating and said analyzer grating is a line absorption grating with high X-ray absorption; a mechanism for placing the sample to be investigated either between said X-ray source and the said beam splitter grating or between said beam splitter grating and said analyzer grating; a position-sensitive detector with spatially modulated detection sensitivity having a number of individual pixels; means for recording images of said position-sensitive detector, a series of M images is collected by continuously or stepwise rotating from zero (0) to pi (π) or 2pi (2π) either the sample or said gratings and said X-ray source relative to the sample, wherein each image taken at an angle 0≦φ≦π contains a corresponding reverse projection image taken at an angle π≦φ+π≦2π, yielding in total a number of M/2 pairs of specular images; means for calculating pixel-wise an absorption image M and an refraction angle θ where: (x, y, z) are first spatial coordinates associated with the sample; (x where φ is a rotation angle between x I I(x x D is a distance between said phase grating and said analyzer grating;  is a shifting curve; C is a constant; and M(x