METHOD AND APPARATUS FOR MONITORING THE SURFACE PROFILE OF A MOVING WORKPIECE

摘要

The present disclosure describes a method and an apparatus for monitoring the surface profile of a moving workpiece at different positions along this workpiece. The apparatus comprises at least one optical unit including a light projecting system for illuminating discrete points on a first surface of said workpiece by projecting more than one discrete coplanar light beams. Each discrete light beam is projected at a different angle of incidence. The optical unit also comprises a light detecting unit for imaging said illuminated points, and generating electrical signals indicative of the surface profile at different positions along the first surface. In a preferred embodiment the thickness of the workpiece can be evaluated by positionning optical units for monitoring the opposite profiles of the workpiece along its whole length.