Patent ID: 7936464

Claim:
A measuring device for determining the surface of an object being measured using optical radiation, the measuring device comprising an optical source; an optical radiation processing unit arranged to direct different wavelengths of the optical radiation of the optical source to the object being measured from a direction differing from the normal of the surface being measured in such a manner that the different wavelengths focus on different heights in the direction of the normal of the surface being measured; a detector to which the optical radiation processing unit is arranged to direct the optical radiation that the optical radiation processing unit is arranged to receive from the object being measured at least from the direction of specular reflection that differs from the direction of the normal of the surface being measured; a signal processing unit arranged to determine from the detected optical radiation on the basis of the signal provided by the detector the wavelength on which the intensity of the optical radiation is the highest and to determine the location of the surface being measured using the determined wavelength.