Comparison of refraction information extraction methods in diffraction enhanced imaging.

Diffraction enhanced imaging (DEI) is a powerful phase-sensitive technique that generates the improved contrast of weakly absorbing samples compared to conventional radiography. The x-ray refraction contrast of the sample is an important contrast in DEI, and it vastly exceeds the absorption contrast for weakly absorbing samples imaging, which makes it hold great promise for medical, biological and material applications. In order to effectively utilize the refraction contrast, the key procedure is first to obtain the refraction information expressed as the refraction image. By comparing the signal-to-noise ratio (SNR) of the refraction image, x-ray radiation dose of the sample and the range of obtained refraction angles, the different refraction information extraction methods are investigated in this paper, and the experimental results confirm the conclusion.