Grating Based X-ray Imaging At SSRF And Its Application In The Research Of Coherence Property

Since the appearance of Grating based X-ray imaging method, it became thehot research fields quickly. It can retrieve absorption, phase and dark-fieldinformation from one set of raw data. It not only maintains the advantages ofX-ray absorption imaging, but also has the advantages of phase contrast and darkfield imaging, those signals are independently and complementally, respectively.Thus, it has great research value and promising future for practical applications.This thesis build up the Grating based X-ray imaging method and system atthe X-ray Imaging and Biomedical Application beamline(BL13W) of ShanghaiSynchrotron Radiation Facility(SSRF) and optimize the system. At same time,based the X-ray grating interferometer, study the coherence property of the X-rayirradiate from BL13W of SSRF. The main contributions of this thesis aresummarized as follows:1. Carry out the research about Grating based X-ray imaging at X the X-rayImaging and Biomedical Application beamline of (SSRF). Firstly, establishthe grating based X-ray imaging setup, and code the data process software;And then do same research about quantitative study and medical application.All the results shown that the feasibility of the system and can be open foruser.2. Optimized the Grating based X-ray imaging system based EST algorithm. Bythe means of translation of the coordinates, transform the rotation variabledifferential phase data to rotation invariable data, which can apply ESTalgorithm to reconstruction. The simulation and the experimental resulttestified the feasibility of the proposed method, and the method can efficiently decrease the data acquisition time.3. Based on the grating interferometer, study the coherence property of theX-ray irradiate from SSRF. Based on the theory of partially coherent lighttheory and VanCittert-Zernike theory, built the relationship betweencoherence degree of the X-ray beam and the visibility of the interferencefringe, test the visibility of the interference fringe by grating interferometer,and then calculate the coherence length of X-ray. The tested result is goodagreement with the theoretical value and the method can provide a referenceto the correlation research.