Observing moving surface of workpiece involves polygonal mirror rotating at revolution rate adapted to speed of surface so image field of video camera projected onto workpiece surface moves approximately at same speed as workpiece surface

摘要

The method involves using a video camera (4) and a polygonal mirror (6) in the beam path between the workpiece (2) surface and the camera and rotating about an axis (10) perpendicular to the direction of motion with a revolution rate adapted to the speed of the surface so that an image field (B) of the camera projected by a mirror surface onto the workpiece surface moves approximately at the same speed as the surface of the workpiece in the direction of motion. An independent claim is also included for a device for observing a moving surface of a workpiece.