Surface defect i.e. micro scratch, detecting device, for e.g. thin film transistor-flat screen, has enlargement unit arranged between surface and illuminator, which is oriented transverse and perpendicular to feed direction of substrate

摘要

The device has a line-illuminator illuminating a detection area (16) of a substrate surface, and a detector (18) detecting light (20) emitted by the illuminator. The illuminator and the detector are arranged relative to each other. An optical aperture enlargement unit (24) is arranged between the illuminator and the substrate surface to enlarge optical aperture of the light emitted by the illuminator. The illuminator is oriented transverse and perpendicular to a feed direction (12) of a substrate (10). An independent claim is also included for a method for optically detecting a surface defect i.e. micro scratch, of a substrate.