TFT-LCD panel Blob-Mura inspection using the correlation of wavelet coefficients

In this paper, we propose a Mura detection method in LCM panel using wavelet transform. Generally, the defect in LCM is so burred that the Mura boundary between defect and background is not clear. To detect and recognize exactly the boundary part of the defect, discrete wavelet transform is used. Then considering the relationship of wavelet coefficients, the significant and insignificant coefficients are separated. After the OR logical operation, closing morphological operation are performed to detect the Mura defect. By the experiment, the proposed method shows promising results for Mura detection in LCM panels.

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