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Since 1971, when the EMI scanner appeared on the market, work on optimizing the hardware of X-ray tomography complexes has not stopped for a single day. X-ray sources are constantly being improved (brighter, more stable, etc.), detectors (increased sensitivity, resolution, etc.), new geometric schemes and modes of projections collecting are being proposed. Another component of the tomographic complex is a computer that implements, in addition to starting measurements and controlling them, pre-processing of collected projections and reconstruction of a 3D digital image of an object, its processing and analysis. This paper presents mathematical approaches to working with tomographic projections collected in different schemes, as the basis for implementing reconstruction algorithms. The words scheme in the work are understood as monochromatic or polychromatic scanning was performed, what type of signal was recorded (transmission, fluorescent, phase contrast), whether the optical element was installed in the optical path. [ABSTRACT FROM AUTHOR]

We present integrated lens system (ILS), which consists of 6 compound refractive lenses with the same focal distance of 0.5m, but optimized for discrete set of energies such as 10, 12, 14, 16, 18, 20 keV. Focusing properties were tested at the ESRF BM-5 and ID18F beamlines. It was shown, that all compound refractive lenses in the system focus X-rays at 0.5 m with accuracy of 2% in changing energy according to the lens design. Focusing of 0.6 micron with the gain of 50 was demonstrated at 14 keV. © 2004 American Institute of Physics [ABSTRACT FROM AUTHOR]

First experimental results of fluorescence microtomography in “pencil-beam” geometry with 6 μm resolution obtained at the ESRF/ID 22 are described. Image reconstructions are based on either a simplified algebraic reconstruction method (ART) or the filtered back-projection method (FBT). Simple cylindrical test objects are accurately reconstructed. [ABSTRACT FROM AUTHOR]

With increasing of X-ray energy an interesting situation appears when due to different dependence of refraction and absorption on X-ray energy a sample becomes transparent but still produces refraction. So such samples become unvisible for usual absorption methods but could be analyzed with various phase contrast methodes. The situation becomes more actual for higher X-ray energy especially for range20-100keV. F. Polack and D. Joyeux described an extension of an interferential differential phase contrast to scanning X-ray microscopy. The principle is to illuminate two points of an object with coherent radiation and detect the fringe shift induced by small phase differences. Fresnel mirrors have been suggested to split a X-ray beam in two coherent ones. In this paper it is proposed instead to use bifocal (multi-focal) lenses. Design and fabrication process of the lenses are described. [ABSTRACT FROM AUTHOR]