Measuring the depth of conducting coatings with gap and substrate-conductivity detuning

Resumo

The problem of measuring the depth of nonmagnetic conducting coatings on nonmagnetic substrates with simultaneous detuning of the gap and substrate conductivity is considered. It is shown that the gap can be detuned by introducing a compensating voltage with a fixed phase and an amplitude that is adjusted proportionally to the high-frequency channel signal.