Collimation and monochromatization

Advanced collimation and monochromatization techniques are described in D.K. Bowen and B.K. Tanner, High resolution x-ray diffractometry and topography, Taylor Francis, London/Bristol, PA (1998). 

Instrumentation. In most studies reported so far. X-ray radiation of a synchrotron collimated and monochromatized with suitable optics is used. An electrochemical cell with a moving working electrode is employed in order to minimize X-ray absorption by the electrolyte solution. A typical cell design is depicted in Fig. 6.10. 

Laser a term for light amplification by stimulated emission of radiation, a laser is a cavity with mirrors at the ends, filled with material such as crystal, glass, liquid, gas or dye produces an intense beam of light with the unique properties of coherency, collimation, and monochromaticity... 

Scattering on the Triple-Axis-Diffractometer [1,2] at the HASYLAB high-energy beamline BW5 is performed in the horizontal plane using an Eulerian cradle as sample stage and a germanium solid-state detector. The beam is monochromatized by a singlecrystal monochromator (e.g. Si 111, FWHM 5.8 ), focused by various slit systems (Huber, Riso) and iron collimators and monitorized by a scintillation counter. The instrument is controlled by a p-VAX computer via CAMAC. 

In the modern era, flashlamps have been superceded by pulsed laser sources which are monochromatic, highly collimated, and have a much higher repetition rate. With a single laser source, the probe pulse can be a small part that is split off from the main pump beam, to therefore be of the same wavelength. Such an arrangement is restricted to the measurement of the kinetics of repopulation of ground-state absorption removed (bleached) by the pump pulse. This method has been employed fruitfully in several laboratories [53-56]. 

SAXS measurements were made at the National Center for Small Angle Scattering Research (NCSASR) at Oak Ridge National Laboratory using the 10m SAXS camera. The instrument used a rotating anode CuK (X" 0.1542 nm) x-ray source, crystal monochromatization of the incident beam, pinhole collimation, and a two dimensional, position sensitive, proportional counter. Sample to detector distance was 1.12 m. Disc-shaped samples were cut from the molded films and dried in a vacuum oven at 65 °C for four weeks prior to the SAXS analyses. 

X-RAY LASERS are devices that amplify very short wavelength radiation along a well-defined direction in order to obtain an intense, collimated, and coherent beam of monochromatic and penetrating emission. Such a radiation source can be used for photolithography of microcircuitry, holographic microscopy of cellular structure in biology, plasma diagnostics, and many other scientific and technical purposes. 

With conventional X-ray sources, a Kratky-type of SAXS instrument with a block collimation system [10] (see Figure 6.3) is often used [11]. For flux optimization and resolution (of the X-ray beam), such instruments have used a slit geometry for collimation and a simple filter for monochromatization. However, these instruments suffer from the disadvantage that, due to anisotropy resolution... 

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