Laser Inspection for Distinguishing Real Crack from Suspected Defects of Glass Boards

Abstract

We proposed an additional optical algorism to improve the functionality of the conventional in situ glass inspection system of finding out real cracks in the glass boards of LCD and OLED. The modulated pulse laser output was used as an optical probe to investigate glass plates. Two parameters of the attenuated laser pulse counting and the decrease of transmitted optical power were used to modify crack detection algorism. Compared to that of the conventional in situ glass inspection method, the detecting accuracy of real cracks was increased with the additional laser inspection method. The technical parameters for analyzing glass defects were discussed such as pulse repetition rate of the incident laser, moving speed of glass board, and attenuation of the transmitted laser power. We also discussed the field adaptation factors of focal length, spot size and wavelength of the incident laser as well as the experimental field data of the laser inspection added system.