Optical Device for Measuring the Thickness of an at Least Partially Transparent Medium

摘要

The inventive optical device for measuring the thickness of a medium which is at least partially transparent for an incident beam and covers a second medium comprises a laser for generating the light incident beam in such a way that a beam reflected by the first medium surface and a beam scattered by the second medium surface are formed. The device comprises a photosensitive linear array for detecting the reflected beam and the scattered beam and a processing circuit which is connected to the linear array and enables to measure a space between the reflected beam and the scattered beam and to determine the thickness of the first medium according to the measured space. The processing circuit determines a distance between the linear array and the surface of the second medium from the position of at least one beam and corrects the valve of the thickness of the first medium according to the distance.