Surface defect inspection method and device of light-transmitting member

• Main Author: KAMEOKA YASUHIRO
• Format: Patent
• Language: Chinese; English
• Published: 12.06.2020
• Subjects: INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIRCHEMICAL OR PHYSICAL PROPERTIES; MEASURING; PHYSICS; TESTING

The present invention provides a method and an apparatus for inspecting the surface defects of the inspected body with high degree of freedom in the arrangement of inspection equipment with respect toa light-transmitting inspected body with high accuracy. A pattern irradiation unit composed of a light-dark pattern forming light shield and an illuminating light source in which light-transmitting parts and light-shielding parts are alternately continuous is arranged on the back side of the light-transmitting object. The imaging unit transmits the bright and dark patterns irradiated by the inspection object imaging pattern irradiation unit, and the detection unit as the image processing device inspects the surface defects of the inspection object based on the change in the emitted light amount (brightness) in the captured image. Since the depth of field of the photographing unit is adjusted so that the photographed image of the bright and dark pattern becomes uniform gray without the boundary between the bright