Strategy of extraction methods and reconstruction algorithms in computed tomography of diffraction enhanced imaging.

Computed tomography of diffraction enhanced imaging (DEI-CT) is a novel x-ray phase-contrast computed tomography which is applied to inspect weakly absorbing low-Z samples. Refraction-angle images which are extracted from a series of raw DEI images measured in different positions of the rocking curve of the analyser can be regarded as projections of DEI-CT. Based on them, the distribution of refractive index decrement in the sample can be reconstructed according to the principles of CT.

Refraction-angle resolution of diffraction enhanced imaging.

As a new method, x-ray diffraction enhanced imaging (DEI) has extremely high sensitivity for weakly absorbing low-Z samples in medical and biological fields. Conventional performance parameters, such as spatial resolution and low-contrast resolution, are not enough to describe the characteristics of a DEI system. This paper focuses on refraction-angle resolution which describes the ability of a DEI system to differentiate the x-rays refracted by the sample.