PRECITEC CHRocodile C, Руководство по эксплуатации

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2.10 CHRocodile C performance specifications:
Axial Resolution / Repeatability:
Axial resolution / Repeatability corresponds to the static noise (standard deviation 1

) on altitude or
thickness measurements. Axial resolution is measured on 1000 continuous points at different target
positions inside the measuring range. By default axial resolution specification corresponds to the
minimum value (R
min
) along the measuring range ( See Fig. 2-9 ). The minimum value (R
min
)
corresponds to the target position where the signal to noise ratio is maximum. Resolution is inversely
proportional to the signal intensity.
Fig 2-9: Axial Resolution as a function of target position in measuring range.
Accuracy:
Accuracy corresponds to the altitude deviation between the CHRocodile C and a calibrated
interferometric reference sensor as a function of target position in the measuring range. Consequently,
accuracy is an experimental specification. By default accuracy specification corresponds to the
maximum of absolute value (A
max
) ( See Fig. 2-10 ).
Fig 2-10: Accuracy as a function of target position in Measuring Range.
Position in the
Measuring Range
Channel p
Axial Resolution (nm)
R
min
0
0
Position in the
Measuring Range
Channel p
Accuracy (nm)
A
max
0