Photothermal coating thickness measurement
The measurement method behind the OptiSense success
Contactless, fast and efficient: The photothermal coating thickness measurement is a contactless measurement method for paints, powder coatings and glazes on metallic and non-metallic substrates. The different thermal properties of the coating and the substrate are used to determine the coating thickness.
The surface of the coating is warmed up by a few degrees with a short, intense light pulse and then cools down again by dissipating the heat into deeper areas. The thinner the coating, the faster the temperature drops. The temperature curve over time is recorded with a highly sensitive infrared sensor and converted into the coating thickness.
The light pulse can be generated in various ways. Compared to xenon flash lamps, LEDs and diode lasers offer all the advantages of semiconductor technology such as long service life, high efficiency and absolute shock resistance.

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A light beam heats the coating surface
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The heat travels downwards through the coating
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The coating cools down again at a rate depending on the coating thickness
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A detector measures the cooling time and uses it to calculate the coating thickness

