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Polycapillary optics, i.e. shaped arrays consisting of hundreds of thousands of hollow glass capillary tubes, can be used to redirect, collimate or focus X-ray beams. X-rays emitted over a large angular range from conventional laboratory-based sources can be transformed into a beam with a small angular divergence or focused onto a small sample or sample area. Convergent beams of X-rays, with convergence angles as high as 15 , have been produced using polycapillary X-ray optics. Focused-spot sizes as small as 20 mm have been achieved, with¯ux densities two orders of magnitude larger than that produced by pinhole collimation. This results in a comparable decrease in data collection times because of the increase in direct-beam intensity and reciprocal-space coverage. In addition, the optics can be employed to reduce background and provide more convenient alignment geometries. The inverse dependence of the critical angle for total external re¯ection on photon energy results in suppression of high-energy photons. This effect can be employed to allow the use of higher tube potentials to increase the characteristic line emission and has also been employed to increase signi®cantly the K/K ratio in Cu radiation. Measurements of X-ray diffraction data and crystallographic analyses have been performed for systems ranging from elemental crystals to proteins. Data from a lysozyme protein`standard' with a slightly convergent beam, taken in 3 min per frame with 2 oscillation with a 2.8 kW source, re®ned to an intensity variance of 5% compared to a standard data set. High-quality data were also obtained with a 0.03 kW ®xed-anode source and a 2 convergent lens in 5 min per frame.

A hard-x-ray telescope is successfully produced for balloon observations by making use of depth-graded multilayers, or so-called supermirrors, with platinum-carbon (Pt/C) layer pairs. It consists of four quadrant units assembled in an optical configuration with a diameter of 40 cm and a focal length of 8 m. Each quadrant is made of 510 pieces of coaxially and confocally aligned supermirrors that significantly enhance the sensitivity in an energy range of 20-40 keV. The configuration of the telescope is similar to the x-ray telescope onboard Astro-E, but with a longer focal length. The reflectivity of supermirrors is of the order of 40% in the energy range concerned at a grazing angle of 0.2 deg. The effective area of a fully assembled telescope is 50 cm2 at 30 keV. The angular resolution is 2.37 arc min at half-power diameter 8.0 keV. The field of view is 12.6 arc min in the hard-x-ray region, depending somewhat on x-ray energies. We discuss these characteristics, taking into account the figure errors of reflectors and their optical alignment in the telescope assembly. This hard-x-ray telescope is unanimously afforded in the International Focusing Optics Collaboration for muCrab Sensitivity balloon experiment.

The International Focusing Optics Collaboration for microCrab Sensitivity (InFOCmicroS) balloonborne hard x-ray telescope incorporates graded Pt/C multilayers replicated onto segmented Al foils to obtain the significant effective area at energies previously inaccessible to x-ray optics. Reflectivity measurements of individual foils demonstrate our capability to produce a mass quantity of multilayered foils with a rms roughness of 0.5 nm. The effective area of the completed mirror is 78 and 22 cm2 at 20 and 40 keV, respectively. The measured half-power diameter is 2.0 +/- 0.6 are min (90% confidence). The successful completion of this mirror demonstrates its applicability to future x-ray telescopes such as Constellation-X.

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