Geometric Modeling of Illumination on the TFT-LCD Panel using Bezier Surface

In this paper, we propose a geometric modeling of illumination on the patterned image containing etching transistor. This image is captured by a commercial camera during the inspection of a TFT-LCD panel. Inspection of defect is an important process in the production of LCD panel, but the regional difference in brightness, which has a negative effect on the inspection, is due to the uneven illumination environment. In order to solve this problem, we present a geometric modeling of illumination consisting of an interpolation using the least squares method and 3D modeling using bezier surface. Our computational time, by using the sampling method, is shorter than the previous methods. Moreover, it can be further used to correct brightness in every patterned image.

Authors:

• Kyong-min Lee
• Moon Soo Chang
• PooGyeon Park

Keywords:

• Bezier
• defect
• geometric modeling
• illumination
• inspection
• LCD
• panel.

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