摘要
For weakly absorbing materials, image contrast can be enhanced by phase contrast in formation. The effectiveness of the in-line phase contrast technique relies on its ability to record intensity data which contain information on the x- ray's phase shift. Four kinds of approaches to the relationship between intensity distribution and phase shift axe reviewed and discussed. A micro-focal x-ray source with high geometrical magnification is used to acquire phase contrast images. A great improvement on image quality is shown and geometrical parameters axe modified for comparison between different imaging positions.
For weakly absorbing materials, image contrast can be enhanced by phase contrast in formation. The effectiveness of the in-line phase contrast technique relies on its ability to record intensity data which contain information on the x- ray's phase shift. Four kinds of approaches to the relationship between intensity distribution and phase shift axe reviewed and discussed. A micro-focal x-ray source with high geometrical magnification is used to acquire phase contrast images. A great improvement on image quality is shown and geometrical parameters axe modified for comparison between different imaging positions.
基金
Project supported by the National Natural Science Foundation of China (Grant No 10475044).