High-resolution high-efficiency X-ray imaging system based on the in-line Bragg magnifier and the Medipix detector

摘要

The performance of a recently developed full-field X-ray micro-imaging system based on an in-line Bragg magnifier is reported. The system is composed of quasi-channel-cut crystals in combination with a Medipix single-photon- counting detector. A theoretical and experimental study of the imaging performance of the crystals-detector combination and a comparison with a standard indirect detector typically used in high-resolution X-ray imaging schemes are reported. The spatial resolution attained by our system is about 0.75 m, limited only by the current magnification. Compared with an indirect detector system, this system features a better efficiency, signal-to-noise ratio and spatial resolution. The optimal working resolution range of this system is between 0.4 m and 1 m, filling the gap between transmission X-ray microscopes and indirect detectors. Applications for coherent full-field imaging of weakly absorbing samples are shown and discussed.