Abstract: An optical inspection system for the inspection of circular workpieces (1) includes an electronic camera (6) having an optical system (21) for focusing an image of a circular workpiece (1) on an electronically active image receiving surface (23), means (16) to move the circular workpiece (1) into a predetermined position in the field of view of the optical system (21) of the camera (6). When a conventional electronic camera is used to inspect circular workpieces it is very difficult to analyze the output signal from the camera since it corresponds to chords taken across the workpiece (1). To overcome this the present inspection system includes means (7) for scanning the image receiving surface in directions extending substantially radially across the image receiving surface to produce an output signal, and a signal analyzer (12) arranged to monitor the output signal corresponding to each radial scan to detect the presence of any irregularity in the workpiece.

Abstract: An optical inspection system for the inspection of circular workpieces (1) includes an electronic camera (6) having an optical system (21) for focusing an image of a circular workpiece (1) on an electronically active image receiving surface (23), means (16) to move the circular workpiece (1) into a predetermined position in the field of view of the optical system (21) of the camera (6). When a conventional electronic camera is used to inspect circular workpieces it is very difficult to analyse the output signal from the camera since it corresponds to chords taken across the workpiece (1). To overcome this the present inspection system includes means (7) for scanning the image receiving surface in directions extending substantially radially across the image receiving surface to produce an output signal, and a signal analyser (12) arranged to monitor the output signal corresponding to each radial scan to detect the presence of any irregularity in the workpiece.