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Abstract: A major challenge facing optic manufacturers is the fabrication of large mirrors (>1 m) with minimal residual slope errors (<0.5 ?rad rms). We present a differential coating method with the potential to satisfy such exacting technical demands. Iterative cycles of measurement using the Diamond-NOM, followed by preferential deposition, were performed on a 1200 mm long, silicon mirror. The applied coatings were observed to reduce the optical slope and figure errors from 1.62 to 0.44 ?rad rms, and from 208 to 13 nm rms, respectively. It is hoped that this research will lead to commercially available products, of direct benefit to the Synchrotron, Free Electron Laser, Astronomy, Space, and Laser communities, who all require state-of-the-art optics.

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Abstract: The Diamond Light, Source beamline 112 (JEEP) is installing a monochromator for high-energy (50-150 keV) X-rays. It consists of two highly asymmetrically cut silicon crystals diffracting in the Laue case. These crystals will be bent to increase the bandpass to several hundred eV. It is necessary to estimate the tolerances for the angular alignment and the bending radii, and to account for gravitational and thermal distortions. A simple ray-tracing model has been developed for use with finite-element analyses. For simple cases, this model is backed by more precise wave-optical calculations.

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Abstract: X-ray compound refractive lenses (CRL) are becoming a widespread tool for the generation of microfocus spot sizes at synchrotron beamlines. The calculation of their performance by means of ray-tracing is useful for a rapid estimation of flux, resolution and focusing properties achievable in a beamline, when other optics are present, or simply to study the lens acceptance and focusing in the presence of a particular bending magnet, wiggler or undulator X-ray source. The ray-tracing method presented in this paper has been used to calculate the efficiency of beryllium CRL's using, for the instrument layout, realistic source size and divergence, and usual optics like perfect crystal monochromators. It is shown that the intensity transmitted by the lens, the effective aperture and the gain are in good agreement with analytical formulas. Additional information provided when running the program are the precise shape of beam at the focus, and at any position along the optical axis. For instance the intensity distribution at the CRL entrance and exit planes allows a comparison between the effective and the geometrical apertures. Finally, the method provides a precise value for the lens focal distance, which depends on the CRL length.

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Abstract: Recently, many experiments have highlighted the advantage of using polycapillary optics for x-ray fluorescence studies. We have developed a special confocal scheme for micro x-ray fluorescence measurements that enables us to obtain not only elemental mapping of the sample but also simultaneously its own x-ray imaging. We have designed the prototype of a compact x-ray spectrometer characterized by a spatial resolution of less than 100??m for fluorescence and less than 10??m for imaging. A couple of polycapillary lenses in a confocal configuration together with a silicon drift detector allow elemental studies of extended samples (?3?mm) to be performed, while a CCD camera makes it possible to record an image of the same samples with 6??m spatial resolution, which is limited only by the pixel size of the camera. By inserting a compound refractive lens between the sample and the CCD camera, we hope to develop an x-ray microscope for more enlarged images of the samples under test.

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Abstract: A laser Fizeau interferometer system has been developed to characterize the figure error of large synchrotron X-ray mirrors using double-pass geometry. This opto-mechanical assembly comprises integrated rotation and translation stages to control: the output angle of the Fizeau interferometer; the surface normal of the optic under test; and the orientation of a high quality (?/100) retro-reflector. To negate the effects of gravitational deformations, the system can measure long optics (up to 1.5m in length) in the geometry (sideward, downward, or upward facing) in which they will ultimately be used on a synchrotron beamline. The system has been designed to minimize environmental noise and enable the measurement geometry to be changed quickly and safely. Compared to complementary techniques, including slope profilers such as the Diamond-NOM, surface height data from the Fizeau system can be obtained more rapidly (<1 minute). This makes the technique ideally suited to investigate the many degrees of freedom of adaptive optics, including piezo bimorph mirrors. The shape of such optics can also be monitored in real time to observe the dynamic effects of the surface in response to applied voltages. Results are presented to illustrate system performance, including repeatability levels. Calibration of the reference surfaces and the required environmental conditions are also discussed.