In the last ten years there appeared a new branch of x-ray optics which was named capillary optics. New optics widely uses the possibility of controlling x-rays during their transmission through systems of bent hollow glass capillaries. Main elements of new optics are concentrating devices which got the name "Kumakhov lenses" . Different types of Kumakhov lenses can be used for solving various problems: focusing radiation onto a small spot, forming quasiparallel beams, filtering radiation, reducing or increasing x-ray images etc. The possibility of controlling x-rays is based on the phenomenon of total external reflection which takes place only at grazing incidence angles. But Kumakhov lenses have large angular aperture because they operate on multiple reflect ions.In this work we investigate the properties of Kumakhov lenses operating on multiple reflections as well as more simple capillary systems which can also focus x-rays but operate mainly on single reflections. The latter systems are capillary structures which have straight hollow mutually parallel channels. Channels may be of different form, for example circular, square or hexagonal.Keywords: Kumakhov lens, x-ray beams, radiation focusing k. MULTIPLE REFLECTIONS SYSTEMS Proposed by M. A. Kuinakhov systems [ 1 , 2] based on the phenomenon of multiple total x-ray external reflection are called Kuinakhov lenses and use for x-ray beams transformation: divergent beam into quasiparallel beam -widening semilens (Fig.la); quasiparallel beam into convergent beam -narrowing semilens (Fig. ib); divergent beam into convergent beam -lens (Fig. ic).Some more intricate modifications of these devices are possible, e.g,such as three-sectional lens consisting of two semilenses with different curvature radii and a straight section smoothly connecting them in the middle (Fig. id). M.A.Kumakhov proposed also certain schemes of total external reflection for getting x-ray filters [3].Geometry of these devices (length L, focal distance F, minimum and maximum cross-section diameters D1 and D2 -see Fig.1) is mainly determined by 2 factors: by demands to the sizes and focal distance of a lens determined from experimental conditions and demands to the lens transmission, focal spot size and final beam angular divergence.The fulfillment of the second group of conditions can be obtained only in case if all lens capillaries (both central and peripheral) take part in beam forming. Because of the fact that peripheral capillaries turn radiation to larger angles (e.g., in case corresponding to Fig. ic this angle is 2'p) x-ray 200 / SPIE Vol. 2278 X-Ray and UV Detectors (1994) 0-8194-1602-9/94/$6.O0 Downloaded From: http://proceedings.spiedigitallibrary.org/ on 07/03/2016 Terms of Use: http://spiedigitallibrary.org/ss/TermsOfUse.aspx

Method of objective estimation the efficient size of the x-ray tube focal spot by means of non-slit collimator is described.

Two types of focal plane image processing chips are presented. They address the two extremes of the application spectrum: general purpose and application specific designs. They both exploit the promise of focal-plane computation offered by CMOS technology.The general-purpose computational sensor, a 16 x 16 pixels prototype (easily scalable to larger arrays), has been fabricated in a standard 1.2µ CMOS process, and its spatiotemporal filtering capabilities have been successfully tested. An array larger than 300 x 300 array will use only 0.5% of the chip area for the processing unit while providing multiple spatiotemporally processed images in parallel. The 16 x 16 chip performs 1 GOPS/mW (5.5-bit scale-accumulate) while computing four spatiotemporal images in parallel. The application specific system realizes a hybrid imaging system by combining a 120 x 36 low-noise active pixel sensor (APS) array with a 60 x 36 current mode motion detection and centroid localization array. These two arrays are spatially interleaved. The APS array, which integrates photo-generated charges on a capacitor in each pixel, includes column parallel correlated double sampling for fixed pattern noise reduction. The current mode array operates in continuous time, however, the programmable motion detection circuit indicates if the intensity of light at pixel is time varying. The centroid, x and y position, of all time varying pixels is computed using circuits located at the edges of the array. Clocked at greater than 60 fps, the chip consumes less than 2mW. The application specific system realizes a hybrid imaging system by combining a 120 x 36 low-noise active pixel sensor (APS) array with a 60 x 36 current mode motion detection and centroid localization array. These two arrays are spatially interleaved. The APS array, which integrates photo-generated charges on a capacitor in each pixel, includes column parallel

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