Analysis of Light Leakage of LCD Module and Improvement by Cell Rubbing Angle

Abstract

We discuss the light leakage issue of LCD due to stress to the polarizer from the backlight temperature. To detect light leakage, we measured black luminance and low gray scale curves by backlight running time. The result shows that gray scale curve's change at upper side of light leakage shift up and that of right and left side shift down. These phenomena are similar to phenomenon from variation of WV-TAC axis. To discuss this result, we insist the heated part of polarizer must be expanded. Finally, our experiment result by changing rubbing angle of cell shows improvement of light leakage.

Structure and application of polarizer film for thin-film-transistor liquid crystal displays

“…Light leakage of polarizer film induced by temperature gradient and non-uniform thermal stress distribution from backlight is the most normal and serious problem for a LCD panel [96][97][98]. The light leakage of a TN mode LCD panel in the black state is shown in Fig.…”