METHOD AND APPARATUS FOR DETERMINING THE IMAGE CLARITY OF A SURFACE

摘要

Method for determining the image clarity of a surface of a sheet, strip or similar, comprising reflection of an image on the surface, detection of a virtual image of the image projected onto the surface and the processing of the detected virtual image of the image projected onto the surface into a signal that is presented as a measure for the image clarity of the surface, wherein the image reflected onto the surface is composed of a number of distinctive light spots and wherein the number of distinctive light spots is determined from the virtual image detected, which number determines, at least in part, the magnitude of the signal.