X-ray Single Grating Phase Contrast Fast Imaging Technology

Since X-ray was discovered,its imaging technology has been widely used in nondestructive testing and clinical medicine,which bringing great convenience to human beings.However,it still has many shortcomings,such as the inability to detect light elements.To solve this problem,X-ray phase-contrast imaging emerged at the right moment.X-ray phase-contrast imaging is free from the limitations of synchrotron radiation sources and is currently closer to clinical implementation.Because X-ray grating phase contrast imaging is based on Talbot-Lau effect,which need multiple gratings for imaging experiments.There are many reasons making it unable to be implemented in clinical applications,such as cumbersome data collection results in a long time for the collected samples to receive X-ray exposure,grating manufacturing process is demanding.To this end,research scholars all over the world have invested a lot of energy to solve this problem.Han Wen et al.successfully extracted the phase information and scattering information of the sample by using a Fourier transform method through a one-dimensional grating.H.W.Lim et al.optimized on the basis of previous contributions and successfully simulated the singlegrating X-ray phase contrast imaging process and obtained better simulation results.The grating fabrication process required by this method is simple,which only requires a single exposure,reduces the amount of radiation received by the measured object,and the imaging system is simpler than the traditional multi-grating phase contrast imaging.Compared with the traditional X multi-grating phase contrast imaging,it is more close to the practical application.Based on the method of X-ray single grating phase contrast imaging,this paper builds an X-ray single grating phase contrast imaging system in the laboratory.Under laboratory conditions,the following work has been carried out on the imaging system parameters of Xray single-grating phase-contrast imaging,the optimization selection of imaging recovery algorithm and the image noise removal,etc.First,an X-ray single-grating phase-contrast imaging system was built to explore the relationship between system structural parameters and imaging.That is,the effect of the distance between the experimental sample and the X-ray source on the final imaging effect under different imaging system lengths;Secondly,the relationship between filtering parameters and imaging of single grating Xray phase contrast imaging algorithm is explored.And the influence of filtering Windows of different shapes and different window sizes on the final imaging recovery results was explored through experiments.Thirdly,the noise reduction problem of single grating X-ray phase contrast image is explored,the factors causing X-ray image noise are introduced,and the single grating phase contrast image is processed by general digital image processing method.