Scatter collimator

The scattered radiation V3 is to high wavenumber of Vj (i.e. on the anti-Stokes side) and is coherent, unlike spontaneous Raman scattering hence the name CARS. As a consequence of the coherence of the scattering and the very high conversion efficiency to V3, the CARS radiation forms a collimated, laser-like beam. 

Several practical issues of the scatterometer must be considered in the case of characterizing nominally smooth surfaces. The incident laser beam may be collimated, but more commonly it is brought to a focus at a distance defined by the arc in which the detector rotates. In addition, a deflection mirror or an optical fiber might be used to direct light to the detector element. These features permit measurements close to the specular and transmitted beams, and this is critical to folly characterize the scattered light. This is especially significant since the scattered light intensity... 

Detection limits for various elements by TXRF on Si wafers are shown in Fig. 4.13. Synchrotron radiation (SR) enables bright and horizontally polarized X-ray excitation of narrow collimation that reduces the Compton scatter of silicon. Recent developments in the field of SR-TXRF and extreme ultra violet (EUV) lithography nurture our hope for improved sensitivity down to the range of less than 10 atoms cm ... 

Optical particle counters provide information on the particles present in different size ranges. A beam of light is collimated and focused onto a measurement cell. Light impinging on a particle is scattered and reaches a photomultiplier tube and converted to an output proportional to particle size. Particle size distributions are computed by appropriate software. 

Deviating from the setup discussed earlier, the y-ray beam can also be consistently collimated by structures other than the absorber holder. If this is the entrance window of the detector, the counter should have a lead shield, and the absorber must be sufficiently large to prevent radiation from passing by. For Mossbauer scattering experiments, the same arguments have to be considered. 

In this section we consider the problem of scattering of a well-collimated beam of high-energy electrons of energy E0 by a crystal. The incident electron wave function then has the form of a plane wave... 

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. 

Collimated Single Scattered beam crystal radiation... 

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