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In-Process measurement and repair of sealant on LCD glasses

During the LCD manufacturing, sealant is printed on a color filter glass and is then adhered to a thin film transistor glass. Liquid crystal is then filled into the space between the two glasses, which is sealed by the sealant. Because missing or narrow sealant causes leakage of the liquid crystal, its detection and repair are important tasks during the LCD manufacturing. In this project, Dr. Kang developed a processing algorithm to segment sealant regions over complex LCD patterns using frequency domain analysis. Also, he developed a sealant repair system to repair missing or narrow sealant with 40um resolution.

 

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Examples of Result Images of Sealant Segmentation
(green lines shown on the images are the segmentation result)

 

The Sealant Repair System

 

The Calibration for Sealant Repair

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