| 摘要 |
PURPOSE:To make rising time constant even if the number of lighting element dot numbers differ so as to prevent change in luminousity by making bias of a switching element rise or decrease with trapezoidal wave form. CONSTITUTION:Gate voltage applied to a gate 10G of a switching element in writing rises with trapezoidal wave form according to time determined by constant current from a charging switching element 12 and capacity C of high durability condensor 14, and trapezoidal voltage generates at a resistor 11, and then, a thin film EL element A rises with trapezoidal wave form. It decreases with the trapezoidal wave form according to time determined by the constant current of a discharging switching element 13 and the capacity C of the condensor 14, while the element A decreases with the trapezoidal wave form through a diode D1. It is thus possible to make rising time constant even if the lighting element dot numbers differ, preventing change in luminousity. |
