Theoretical consideration of the drop in threshold voltage at low frequencies in nematic liquid crystals

Research of numerical calculation and theoretical considerations have been applied in relation to the electrical double layer effect on the threshold voltage of liquid crystals in order to understand the drop in threshold voltage often observed at low frequencies. Decreased resistivity of an alignment film was found to contribute to this threshold voltage drop. Moreover, dielectric dispersion due to the electrical double layer at the interface between the liquid crystal and alignment film layers is thought to exist in the frequency range in which the drop in threshold voltage was obtained experimentally. Therefore Debye type dielectric dispersion of the electrical double layer in the system consisting of the nematic liquid crystal and the alignment film also influences the threshold behaviour at low frequencies.