Polytec TMS-350 TopMap In.Line, Hardware Manual

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A-8
A TMS-A-305 Calibration Set
All calculation parameters for the expanded measurement uncertainty are
regarded as being statistically independent. The expanded measurement
uncertainty is calculated from the standard measurement uncertainty by
multiplying with an expansion factor k = 2. With 95% probability, the deviation
to be expected from a new measurement from a (true) value of the groove
depth will be in the value range measurement value deviation ± expanded
measurement uncertainty . The deviation will be above or below this with a
probability of 2.5 % each, respectively.
For every step height, a tolerance value is specified for the measurement
value deviation. To attain a high level of confidence on compliance with the
tolerance values, a worst- case consideration is carried out by adding the
value of the measurement value deviation and the expanded measurement
uncertainty together.
You can assume that with a probability of at least 95%, a new measurement
of the same step height will not deviate from the true value by more than the
sum of the absolute value of the measurement value deviation and the
expanded measurement uncertainty.
The specifications are considered to be complied with if the sum of the
absolute value of the measurement value deviation and the expanded
measurement uncertainty is smaller than the value specified for this step
height.
All calibrated grooves are evaluated groove 1, groove 2, ….