CODED-APERTURE X-RAY IMAGING

摘要

A method of X-ray imaging includes passing an X-ray beam through a pre-sample mask 8 with a plurality of apertures 32, through a sample 10, and then through a detector mask 6 with aligned apertures 34. The beams are detected. The detector mask 6 and pre-sample mask 8 are moved with respect to one another to identify the position of maximum intensity and then moved to two further positions on equal and opposite spacings on either side of the maximum. Images are acquired and a transmission image, refraction image and scattering image calculated.

主权项

1. A method of X-ray imaging, comprising:
passing an X-ray beam through an absorbing pre-sample mask with one or more apertures spaced apart in the x direction; passing the X-ray beam through a sample; detecting the X-rays using a spatially resolving detector representing a detector mask having one or more apertures spaced apart in the x-direction at a corresponding spacing to the apertures in the pre-sample mask, to provide at least one image or images I1, I2 . . . with the relative position of the pre-sample mask and detector mask at respective position or positions x1, x2 . . . ; and obtaining a dark field image of the sample by calculating the dark field image from the captured image or images I1, I2 . . . at respective positions x1, x2 using a formulation representing the image intensity as a function of scattering, transmission and refraction.