Capacitively coupled driving method for TFT-LCD to compensate for switching distortion and to reduce driving power

Claim 1

In a method for driving a display apparatus comprising matrix-arranged picture element electrodes each connected to a first wiring through a storage capacity, each picture electrode being connected to a thin film transistor which is electrically connected to a picture signal wiring and a scanning signal wiring, and liquid crystal material hold between each picture electrode and an opposite electrode and being driven by an alternative current voltage, the improvement thereof comprising the steps of: transferring a picture signal voltage to the picture element electrode during an "on" period of the thin film transistor; feeding a modulation signal which is equal in absolute value and is different in polarity for every field to the first wiring during an "off" period of the thin film transistor to change the voltage of the picture element electrode; loading a voltage across the display material by adding to, or substracted from, the changed voltage of the picture element electrode and the voltage of the picture signal; and keeping at a constant voltage the difference between an average central voltage of picture signal voltage Vst and a voltage Vt of the opposite electrode.