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One-Sided Thickness Measurement, Transparent Target
confocalDT 2421 / 2422
One-Sided Thickness Measurement, Trans-
parent Target
The controller evaluates two signals reflected on the
surfaces. Based on these two signals, the controller cal-
culates the distances from the surfaces and, from this,
derives the thickness.
Align the sensor perpendicularly to the object to
be measured. Make sure that the target is approxi-
mately in the mid of the measuring range (SMR +
0.5 x MR).
i
The light beam must strike the surface of the object
at a perpendicular angle. Otherwise, measure-
ments might be inaccurate.
SMR
MR
Displace-
ment 1
Displace-
ment 2
Thickness
One-sided thickness measurement for a transparent
target
Preset
Switch to the
Home
menu.
Select
One-sided thickness measurement
in
the
Measurement configuration
menu.
This presetting prompts the controller to use the first
and second peak in the video signal for the thickness
calculation.
Material Selection
Specifying the material is essential for calculating a
correct thickness value. To compensate for the spectral
change of the index of refraction, at least three refractive
indices at different wavelengths or a refractive index and
the Abbe number must be known.
Switch to the
Settings > Data recording >
Material selection
menu.
Select the material of the target for
Layer 1
.
