Abstract
Among the methods for imaging failure analysis of Thin Film Transistor Liquid Crystal Display (TFT-LCD) Cell, the measurement of optical characteristics is extremely effective to identify the imaging failure type. We have evaluated time dependency of transmitted light intensity under holding condition at a single pixel level on a LCD Cell. This is defined as Optical Holding Rate (OHR). OHR characterizes the Voltage Holding Rate (VHR) of actual Cell. VHR is generally used for Liquid Crystal evaluation. This method enables us to identify which part of LCD Cell causes imaging failure, especially by measuring OHR as a function of various driving parameters. After classifying the imaging failure modes, we can investigate the failure mechanisms by structure or surface analysis. In conclusion, to measure OHR is effective to identify imaging failure type of LCD Cell.
