METHOD AND APPARATUS FOR INSPECTING FAULT OF PLATE GLASS

摘要

PURPOSE: To provide a method and an apparatus for inspecting a fault of a plate glass which can automatically distinguish whether the detected fault is present inside the glass or outside (including a surface of) the glass. CONSTITUTION: A surface of a plate glass 10 is illuminated with predetermined angles by a laser beam 11a which is thinner than the plate glass. At this time, an illuminated position on the surface of the glass is changed while the laser beam is scanned. The illuminated surface is photographed by a camera 12 from a direction of a regularly reflected light. of the beam 11a. The regularly reflected light from the glass surface is reduced or shut by a filter 13 set in front of a lens of the photographing camera 12. A fault of an image between a position of an image of the beam 11a of the surface of the glass and a position of an image of the beam of a rear face of the glass is judged to be an internal one.