Dual phase grating interferometer may simultaneously achieve large field of view and high x-ray dose efficiency.Here,we develop a simple theoretical method to better understand the imaging process of the dual phase gr...Dual phase grating interferometer may simultaneously achieve large field of view and high x-ray dose efficiency.Here,we develop a simple theoretical method to better understand the imaging process of the dual phase grating interferometer.The derivation process of fringe period and the optimal visibility conditions of the dual phase grating interferometer are given in detail.Then,we theoretically prove that the fringe period and optimal visibility conditions of the dual phase grating interferometer include that of the Talbot interferometer.By comparing our experimental results with those of other researchers,we find that when the positions of phase gratings are far away from the positions where the fringe visibility is optimal,the fringe period of the dualπ-phase grating interferometer is twice the theoretical results under the illumination of polychromatic x-ray.This conclusion may explain the contradictory research results of dual phase grating interferometer among different researchers.展开更多
基金supported by the National Natural Science Foundation of China(Grant Nos.11674232,62075141,and 12075156)the Foundation of Shenzhen Science and Technology Bureau,China(Grant No.20200812122925001)。
文摘Dual phase grating interferometer may simultaneously achieve large field of view and high x-ray dose efficiency.Here,we develop a simple theoretical method to better understand the imaging process of the dual phase grating interferometer.The derivation process of fringe period and the optimal visibility conditions of the dual phase grating interferometer are given in detail.Then,we theoretically prove that the fringe period and optimal visibility conditions of the dual phase grating interferometer include that of the Talbot interferometer.By comparing our experimental results with those of other researchers,we find that when the positions of phase gratings are far away from the positions where the fringe visibility is optimal,the fringe period of the dualπ-phase grating interferometer is twice the theoretical results under the illumination of polychromatic x-ray.This conclusion may explain the contradictory research results of dual phase grating interferometer among different researchers.
