Automatic Neighbor r Selection for One-dimensional DFT Method in the Surface Defect Inspection of TFT-LCD

Abstract

Abstract: In order to obtain neighbor r automatically, each line of a faultless surface image for TFT-LCD panel was preprocessed firstly in the detection of surface defects on TFT-LCD panel. Then thier gray level co-occurrence matrix (GLCM) was calculated, and the homogeneity property of the GLCM was extracted. Finally, the difference of homogeneity was computed, and the optimal neighbor was that level where the difference showed a maximum value. An experimental system of TFT-LCD panel detection was built. The images with various length including integer-period, non-integer-period and non-integer-period filled into integer-period were processed in the experiments. From the acquisition of r, it may be seen that the r for non-integer-period fills into integer-period is the same as it for integer-period under the same environments. And by applying the results into actual defect detection, the system may detect the defects accurately.

Key words: thin film transistor-liquid crystal display, defect detection, gray level co-occurrence matrix, one-dimensional discrete Fourier transform(DFT), neighbor r

摘要： 在TFT-LCD平板表面缺陷检测中，为了自动获取一维DFT方法中的邻域r，首先将无缺陷的TFT-LCD平板表面图像的每一行经过预处理，再计算其灰度共生矩阵，然后提取灰度共生矩阵的均匀度，最后计算不同r时的均匀度差值。最大差值所对应的r就是最佳邻域。搭建了TFT-LCD平板检测实验系统，实验对不同长度的非整周期、整周期、非整周期补整的图像进行处理。从获取的r可知，在相同环境下，非整周期补整后的r和整周期的r相同。将这一结果应用到实际缺陷检测中，系统可以准确地检测出缺陷。

关键词: 薄膜晶体管-液晶显示器, 缺陷检测, 灰度共生矩阵, 一维离散傅里叶变换, 邻域r

CLC Number:

Zhang Tengda, Lu Rongsheng, Dang Xueming. Automatic Neighbor r Selection for One-dimensional DFT Method in the Surface Defect Inspection of TFT-LCD[J]. China Mechanical Engineering.

张腾达, 卢荣胜, 党学明. TFT-LCD表面缺陷检测中一维DFT方法中邻域r的自动选取[J]. 中国机械工程.

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