Typically, contacting gauges based on the eddy current or magnetic-inductive principle are used for coating thickness measurement in the cross-linked state. The disadvantage of these gauges is a complex calibration procedure, since the geometry, conductivity and magnetizability of the underlying workpiece must be taken into account.
Measuring devices for non-contact coating thickness measurement based on Advanced Thermal Optics, on the other hand, are based on the thermal properties of the coating. The thermal properties of different paints and coatings are very similar, but show measurable differences.