Information Retrieval And Noise Properties Of X-ray Grating-based Phase-contrast Imaging

This thesis is on one of the phase-sensitive X-ray imaging techniques,so-called X-ray grating interferometry.It is an imaging technique based on Talbot effect and yields high-sensitive refraction and scattering images along with absorption image of the specimen under ex-amination.It has tremendous potential for visualization of features having low absorption contrast.In this thesis,X-ray grating interferometer has been used to get three contrast images;absorption,refraction and scattering employing angular signal radiography.Quan-titative analysis of noise of three contrast images are performed and then compared with phase-stepping method.Noise analysis of ASR shows how to improve image quality.Noise comparison of ASR and PS shows that for absorption image both methods give similar image quality and for refraction and scattering images the image quality of ASR is higher than PS method.Moreover,integrating-bucket phase modulation method has been used for the first time in X-ray grating interferometry to retrieve phase information.Experimental results show that integrating-bucket method can be used well to extract refraction information.The quantitative analysis of noise of integrating-bucket method has been performed.At the end noise of multi-combination information of angular signal radiography has been quantitatively analyzed.Noise of multi-combination information provide platform to optimize sample information for specific and targeted applications.