FISCHER FISCHERSCOPE X-RAY XDLM 231, Operator'S Manual

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16 FISCHERSCOPE ® X-RAY
Instrument Overview
4. A light source (not shown in Fig. 2.2) illuminates the sample. A mirror and lens direct the image
of the measurement location to a color video camera. The mirror has a hole in its center for the
primary radiation to pass through.
5. The aperture (collimator) limits the cross-section of the primary beam in order to excite a meas-
urement spot of a defined size.
6. The primary x-radiation impacts the atoms on the sample surface (coating layer and base mate-
rial) and in the process knocks electrons from the inner electron shell. Electrons from outer elec-
tron shells fill the resultant voids emitting a fluorescence radiation that is characteristic in its
energy distribution for a particular material.
7. The energy dispersive detector measures the energy distribution of the fluorescence radiation.
A multistage electronics circuit processes the measurement signals.
8. The measured spectrum shows lines or peaks that are characteristic for the chemical elements
in the sample.
9. The WinFTM Software computes the thickness of the coating(s) and/or the analysis result. The
video image of the sample is shown in the WinFTM window. The precise position of the meas-
urement location and the measurement spot is possible due to the special design of the optical
and the x-ray guidance systems.