A general theoretical framework is presented to explain the formation of the phase signal in an x-ray microscope integrated with a grating interferometer,which simultaneously enables the high spatial resolution imagin...A general theoretical framework is presented to explain the formation of the phase signal in an x-ray microscope integrated with a grating interferometer,which simultaneously enables the high spatial resolution imaging and the improved image contrast.By using this theory,several key parameters of phase contrast imaging can be predicted,for instance,the fringe visibility and period,and the conversion condition from the differential phase imaging(DPI)to the phase difference imaging(PDI).Additionally,numerical simulations are performed with certain x-ray optical components and imaging geometry.Comparison with the available experimental measurement[Appl.Phys.Lett.113063105(2018)]demonstrates the accuracy of this developed quantitative analysis method of x-ray phase-sensitive microscope imaging.展开更多
Background The differential phase computed tomography(DP-CT)imaging is a kind of X-ray-phase-based CT methods,which is widely used in various X-ray imaging laboratories.At present,a collection of projections with the ...Background The differential phase computed tomography(DP-CT)imaging is a kind of X-ray-phase-based CT methods,which is widely used in various X-ray imaging laboratories.At present,a collection of projections with the horizontal direc-tion(perpendicular to the sample rotation axis)DP information is often acquired in DP-CT.In an ideal experiment,if the background is zero,then we can accurately reconstruct the information of each direction of the sample with horizontal data only.Actually,background information will produce streaking artifacts to affect the resolution in directions other than the horizontal direction.Purpose To mitigate the streaking artifacts in the conventionally reconstructed DP-CT images.Method This study develops a novel analytical DP-CT reconstruction framework by jointly using the bilateral DP information obtained along two perpendicular directions.In addition,a new data acquisition scheme is also proposed to quickly acquire the bilateral DP signal without the need of changing the direction of refraction signal acquisition.Results Experimental results demonstrate that this new algorithm is able to greatly reduce the streaking artifacts on DP-CT images.展开更多
基金Project supported by the National Natural Science Foundation of China(Grant Nos.12027812 and 11804356)the Youth Innovation Promotion Association of the Chinese Academy of Sciences(Grant No.2021362).
文摘A general theoretical framework is presented to explain the formation of the phase signal in an x-ray microscope integrated with a grating interferometer,which simultaneously enables the high spatial resolution imaging and the improved image contrast.By using this theory,several key parameters of phase contrast imaging can be predicted,for instance,the fringe visibility and period,and the conversion condition from the differential phase imaging(DPI)to the phase difference imaging(PDI).Additionally,numerical simulations are performed with certain x-ray optical components and imaging geometry.Comparison with the available experimental measurement[Appl.Phys.Lett.113063105(2018)]demonstrates the accuracy of this developed quantitative analysis method of x-ray phase-sensitive microscope imaging.
文摘Background The differential phase computed tomography(DP-CT)imaging is a kind of X-ray-phase-based CT methods,which is widely used in various X-ray imaging laboratories.At present,a collection of projections with the horizontal direc-tion(perpendicular to the sample rotation axis)DP information is often acquired in DP-CT.In an ideal experiment,if the background is zero,then we can accurately reconstruct the information of each direction of the sample with horizontal data only.Actually,background information will produce streaking artifacts to affect the resolution in directions other than the horizontal direction.Purpose To mitigate the streaking artifacts in the conventionally reconstructed DP-CT images.Method This study develops a novel analytical DP-CT reconstruction framework by jointly using the bilateral DP information obtained along two perpendicular directions.In addition,a new data acquisition scheme is also proposed to quickly acquire the bilateral DP signal without the need of changing the direction of refraction signal acquisition.Results Experimental results demonstrate that this new algorithm is able to greatly reduce the streaking artifacts on DP-CT images.
