Numerical Modeling and Experiment for Single Grid-Based Phase-Contrast X-Ray Imaging

Conventional x-ray imaging techniques have widely been used for both medical and industrial imaging applications and have in common attenuation-based contrast which arises from differences in elemental composition, thickness, and density of the examined sample. However, they are often limited by low image contrast especially in imaging materials of low atomic number. One possible solution to the problem of limited contrast inherent to attenuation-based radiography is the application of phasecontrast x-ray imaging (PCXI) technique that utilizes the phase shift of the x-ray wavefront introduced by the sample under investigation to the transmitted x-rays. Because the variation in phase of x-rays is much larger than that in intensity due to attenuation, it can detect small features and variations in the sample that would be invisible in conventional attenuation-based radiography. Several techniques have been proposed to measure the phase shift, including analyzer-based imaging, propagation-based imaging, grating-based imaging, etc. However, most of the techniques put higher demands on the equipment, which has limited the widespread use of these techniques into many related applications. In this work, we investigated the recently developed technique by Wen et al., the so-called single gridOriginal Article