Electrical models of liquid crystal display (LCD) have been studied and used in design simulation. Using the right LCD models is indispensable to accomplish high-quality and highly reliable LCDs. This paper presents a cell panel electrical test (Cell-E Test) for evaluating the electrical characteristics of LCDs. The Cell-E Test was derived from in-process electrical testing for thin film transistor arrays, and utilizes charge measurement for measuring the capacitance value of a pixel. The capacitance-voltage (C-V) and capacitance-time (C-t) characteristics can be measured using a sweeping-applied voltage and based on the period of applying voltage in the Cell-E Test. In this study, actual C-V and C-t characteristics were measured by applying the Cell-E Test to a twisted-nematic active-matrix LCD (TN AM-LCD). The parameters of liquid crystal models were extracted from the data measured using the least-squares method, to show that design models can be verified with the actual parameters of cell panels through the Cell-E Test.
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