Generalization of DEI methods in grating-based phase-contrast imaging

Abstract

It has been shown that grating based x-ray phase contrast imaging (GPI) can be performed on x-ray tubes and therefore has a great potential for a wide application in many fields. So far to extract and to separate the phase information from other contributions, a phase-stepping approach is normally adopted. One of the gratings is scanned transversely to the incident beam while acquiring multiple projections of the sample. However, during the grating scanning, the sample is supposed to be static, and the resulting poor time resolution is one of the major drawbacks of this method. It is clear that a method that would extract the phase information without the need of multiple stepping would be a breakthrough enabling fast, highly sensitive (phase-contrast) x-ray imaging. According to the similar physics and mathematics between diffraction enhanced imaging (DEI) and GPI, here we report how the DEI methods can be generalized for GPI and how GPI can use the same acquisition procedure as the conventional absorption CT without grating scanning. © 2011 American Institute of Physics.