Study of internal electric field of liquid-crystal cell effected by space-charge polarization

The distribution of the local electric field in a liquid-crystal cell conta ining mobile ions was simulated in accordance with the Poisson equation in the steady state under a DC voltage application. The distribution of the lo cal field was determined to be markedly unbiased due to the contribution of the bound charges on the electrodes induced by ions. This result suggests that the intensity of the local field acting on ions can be approximated by that of the external field, for analyzing the space-charge polarization un der a small AC voltage application even in a very low frequency region, whe re the diffusion distance of ions during the period of the external AC fiel d becomes greater than the thickness of the cell.