Determining presence of inorganic, organic or oxide layers on metallic substrates comprises arranging electrode at distance to surface, and measuring frequency change as consequence of temperature change

摘要

Determining the presence of inorganic, organic or oxide layers on metallic substrates comprises arranging electrode at a distance to the surface, and measuring the frequency change as a consequence of temperature change. Determining the presence of inorganic, organic or oxide layers on metallic substrates or measuring surface temperatures of plastic substrates comprises arranging an electrode (2) acting as a capacitive or inductive element connected with an oscillator (3) injected with a voltage to an oscillating circuit at a distance to the surface; and measuring a frequency change as a consequence of a temperature change using a frequency counter arising on the surface of a plastic substrate (1) by de-tuning the oscillating circuit. An Independent claim is also included for an apparatus for determining the presence of inorganic, organic or oxide layers on metallic substrates or measuring surface temperatures of plastic substrates. Preferred Features: The electrical voltage is kept constant on the oscillator and is regulated depending on prescribed frequency and the required voltage difference utilized.