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6.2.2 Manual calibration method
6.2.2.1 Zero calibration
”Z” is shown in the status line
calibration point: zero point (directly on the substrate material)
Calibration is to be made on an uncoated calibration sample of the same geometry and material as
the later measuring object. Only one calibration point is to be taken directly on the substrate to give
you the zero point.
Zero calibration is for quick calibration if a medium accuracy is sufficient.
6.2.2.2 Two-point calibration
”Z 1” is shown in the status line
Calibration points: zero point (directly on the substrate material) and on the precision standard.
Calibration is to be made on an uncoated calibration sample of the same geometry and material as
the later measuring object. Two calibration points are to be taken: one directly on the substrate to
give you the zero point, the other one on a precision standard which is put on the substrate.
Compared to the zero calibration, this calibration method implies a higher accuracy. Accuracy will
increase if the thickness of the precision standard is close to the thickness of the later object to be
measured.
6.2.2.3 Multi-point calibration
“Z 12” is shown in the status line.
Calibration points: zero point (directly on the substrate material) and on two precision standards.
Calibration is to be made on an uncoated calibration sample of the same geometry and material as
the later measuring object. Three calibration points are to be taken: one directly on the substrate to
give you the zero point, and two further ones on two precision standards to be put on the substrate.
It is recommended to choose a precision standard to cover the lower half of expected thickness
range, the other one should be in the higher half of expected thickness range.
This calibration method should be used if readings are to be taken over an extended thickness
range and if a high accuracy is required.