An X-ray focusing monochromator composed of poly-capillary X-ray lenses and highly oriented pyrolytic graphite

摘要

An X-ray focusing monochromator is proposed, which is composed of an X-ray source, a highly oriented pyrolytic graphite and two poly-capillary X-ray lenses. Through the function of the front poly-capillary X-ray lens, the X-ray beams diffracted by the highly oriented pyrolytic graphite changed from a linear pattern with high divergence in the vertical direction, to a circular pattern with low divergence, and more X-rays are diffracted than the conventional monochromator of combining an X-ray source with a flat crystal. The post poly-capillary X-ray lens can focus the diffracted X-ray beams with low divergence into a small focal spot with high gain in power density. The results show that the gains of circular apertures with diameters of 320 and 100 mu m are 12 and 22, respectively, at a distance of 221.5 mm away from the center of the highly oriented pyrolytic graphite.