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6.2.2.4 Two-point calibration without zero calibration
”12” is shown in the status line
calibration points: two precision standards (no zero point)
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 on two precision standards which
are to be put on the substrate. The first precision standard should be thinner than the thickness to
be expected, the other one should be thicker than the thickness to be expected. There is no zero
point to be taken directly on the uncoated sample.
This specific calibration method should be used when taking readings on rough surfaces. Taking
zero point on rough surfaces would imply strong deviations due to the uneven surface. That’s why
zero point is omitted in this calibration method as this would lead to erratic calibration and thus
affect accuracy.
6.2.3 Defined, menu-guided calibration methods
6.2.3.1 General remarks
For all defined and menu-guided calibration methods the following applies:
The selection of a defined calibration method is made during the creation of a batch. After you
have completed the set-up of a batch, you may proceed on the menu-guided calibration. The
factory calibration will be valid until you have completed the calibration procedure. A running
calibration procedure is indicated by CAL flashing in the status line.
6.2.3.2 Calibration according to ISO (EN ISO 19840)
“ISO” is shown in the status line.
Calibration points: zero point (directly on the substrate material) and on two precision standards.
This standard does not apply if the target thickness is less than 40 microns.
Calibration is made on the uncoated calibration sample of the same geometry and substrate
material as the later object to be measured. Three calibration points are to be taken: zero point
(directly on the substrate) and two further one on two precision standards which are to be put on
the substrate. The first precision standard should be thinner than the thickness to be expected, the
other one should be thicker than the thickness to be expected.