Detection of various defects in TFT-LCD polarizing film

The increasing use of TFT-LCDs has generated a great deal of interest in manufacturing defects on TFT-LCD polarizing film because the poor quality of TFT-LCD polarizing film result in undesirable effects on the TFT-LCD display devices. In this paper, we propose a new inspection method that reliably detects various defects of TFT-LCD polarizing films. First, we apply a least mean squares adaptive filtering technique to remove background noise. Next, we use statistical characteristics to detect possible defects. Finally, we make a binary image to identify weather the TFT-LCD polarizing film has defects or not based on an adaptive threshold value. The performance of the proposed method has been evaluated on real TFT-LCD polarizing film samples.