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The performance of a system for quantitave microtomography with synchrotron radiation is described with regard to the spatial resolving power. The experimental setup consists of a doublecrystal monochromator, a monitor in front of a sample stage and a line scan detector which is built up of two photodiode arrays (Reticon RL1024SF), which are cooled by Peltier dements to increase the dynamic range. We present the modulation transfer function of the detector and several monitor configurations. So far a spatial resolution of 100 μm has been achieved. [ABSTRACT FROM AUTHOR]

Describes a position sensitive one-dimensional x-ray detector that was developed for transvenous coronary angiography with synchrotron radiation. Dynamic range of the dual line multicell ionization chamber; Spatial resolution; Detective quantum efficiency.

Describes a double beam bent Laue monochromator that is in use at the angiography wiggler beamline W2 at HASYLAB in Hamburg, Germany. Details of bent Laue crystal focusing; Components of the monochromator; Design considerations.

During the last years attempts have been underway at several synchrotron radiation laboratories to employ the abrupt change of absorption at the iodine K edge (33.17 keV) to the imaging of coronary arteries. The subtraction of two images taken with photon energies just above and below the edge strongly surpresses background contrast like bone and soft tissue and allows for amplification of iodinated structure contrast. At HASYLAB, for these studies, a beamline at a bending magnet was only available until 1987. At this beamline the system NIKOS I was tested to obtain information on its essential components like monochromator and detector by in-vivo investigations of dogs. The basic feature which differs from the approaches in other laboratories is the simultaneous registration of two stationary beams in a two-line detector without any beam switching. Based on the experience with this system during the last year all its components have been improved and changed to dimensions capable of taking a 12-cm-wide image of the human heart. At present the new system NIKOS II is under testing at the new wiggler beamline HARWI. The new monochromator comprises two pairs of a thin Si Laue case crystal and a Ge Bragg crystal, each, with inherent focussing of the beam to a horizontal line focus of about 0.5 mm height and 12 cm width. The advantage of the Laue crystals which are optimized in thickness (30 μm) for maximum reflectivity, is the low heat absorption and the full use of the white beam in the production of two monochromatic beams. The crystals are cooled in a stream of helium. Compared to the NIKOS I version the detector was changed in the following points: The two detection lines are enlarged to 125 mm width and the phosphor at the entrance is exchangeable to be either made of powderlike Gd[sub 2]O[sub 2]S :Tb or of single crystals like CdWO[sub 4] or CaF[sub 2]:Eu separated by thin walls for optimum spatial resolution. The numerical aperture of the glass fiber... [ABSTRACT FROM AUTHOR]