STEADY-STATE CURRENT IN NEMATIC LIQUID-CRYSTALS

A steady state current flowing in nematic liquid crystals (NLCs) has b een studied for NLC cells with and without polyimide alignment layers. For the cell without the polyimide layers, the steady state current i s ascribed to the charge injection from the electrodes and the generat ion of mobile ions at lower and higher applied voltages, respectively. For the cell with the polyimide layers, on the other hand, the curren t is much smaller than that of the cell without the polyimide layers. This is due to the fact that the polyimide layers block the charge inj ection from the electrode to the NLC slab and that the external applie d voltage falls entirely in the polyimide layers.