DISPLAY DEVICE FOR SURFACE STATE

PURPOSE:To judge whether it is really a defect or the oil droplet or dirt which is not a defect by observing the surface state of the plate to be inspected as a TV picture. CONSTITUTION:The surface of the plate 8 to be inspected is scanned by the laser beam of an optical unit 1, the surface defect is detected optically, converted into an electrical signal and outputted to an analog processing circuit 3. The analog video signal transmitted from the processing circuit 3 and the symmetrical signal synchronized with the scanning of the laser beam transmitted from the driving circuit 2 composed of an electromagnetic vibration mirror, etc. are then inputted to a frame memory unit 9. The analog video signal inputted into an analog signal input terminal 92 is then converted into the digital data of 6-8 bits per dot by A/D converting circuit, recorded on the frame memory unit 9 and outputted to a TV monitor 10 from a TV signal output terminal 93 in the form of a TV signal. The real defect can thus be found easily and services can be rendered for remarkable improvement in the work efficiency and yield increase in products.