JPS6419327A - Driving method for thermal writing liquid crystal display - Google Patents

Abstract

PURPOSE:To eliminate the influence of a residual voltage and to make the image display faithful to a writing instruction by impressing the voltage which is weaker than a writing voltage and has the polarity different from the polarity thereof to the heating electrodes and signal electrodes of the part of a residual voltage display where the liquid crystal layer is not going to be made transparent. CONSTITUTION:The voltage is impressed to the heating electrodes 11 of the liquid crystal layer from a power supply 16 and to the signal electrodes 12 from a power supply 18. A potential gradient is generated by the voltage drop generated by an internal resistance in the electrodes 11 in an energized state and the voltage correspond ing to the potential gradient remains by the capacity component possessed by the liquid crystal layer even if the power supply is stopped. The part near the power supply is liable to attain the transparent state. The potential gradient is, thereupon, offset by impressing the positive voltage to the electrodes 11 in the part where the liquid crystal layer is not to be made transparent and the negative voltage weaker than the writing voltage to the electrodes 12 by setting switches 17 at contacts 17b for nonwriting. The turbid parts of the liquid crystal layer are thereby prevented from becoming transparent and the image faithful to the writing instruction is dis played.