Simulation of the voltage holding ratio in liquid crystal displays with a constant charge model

A model for simulating the voltage holding ratio in liquid crystal (LC) cells and investigating the influence of ionic impurities on device performance is proposed. Active matrix addressed liquid crystal displays (AM-LCDs) are composed of insulator materials between two electrodes, and are driven by pulse-voltage application. In this model, the charge density accumulated on an electrode is assumed to be constant in the open-circuit state. The voltage decay is described as a change in the internal electric field induced by ion polarization and the increased capacitance caused by LC reorientation. Results calculated using this model qualitatively reproduced measured voltage decays.