Laser-based observation of water condensation on a metal surface

An optodynamic method is presented that allows us to assess the relative amounts of condensed water on a metal surface and to estimate the rate of condensation, which turns out to be a sensitive criterion for assessing the proximity of the dew point. The method is fully laser-supported, from the drying of the metal surface to the excitation of optodynamic waves and their detection by a laser-beam-deflection probe. A pulsed Er:YAG laser has been specially designed and built for this application.