A microbeam collimator for high resolution x-ray diffraction investigations with conventional diffractometers

A collimating system has been developed for condensing hard x rays, providing very thin, intense, and low divergent beams. The primary radiation is compressed down to the micrometer scale by multiple total reflections in the channel between two oblong and flexible metallic mirrors with exit aperture 4 mm×15 μm. The flexible mirrors permit variation of the channel profile and opening for the incoming radiation, adjusted for maximum transmitted x-ray intensities. The condenser, due to the high brilliance gain of the obtained beam compared to the uncompressed radiation going through a slit of the same size, can be operated even with conventional x-ray tubes, e.g., common x-ray diffractometers without the need for expensive high intensity synchrotron radiation sources, as demanded usually by the glass monocapillaries. A prototype, being mounted on a commercial theta–theta diffractometer, has been thoroughly tested for intensity gain, divergence, and spatial resolution and utilized for accurate structure deter...