Liquid-crystal display having the capability of a tablet

Abstract

Disclosed is a liquid-crystal display having the capability of a tablet which offers high image quality and a high response speed. An active matrix type liquid-crystal display having the capability of a tablet comprises: an active matrix type liquid-crystal display composed of a device substrate having a plurality of scan electrodes, a plurality of data electrodes, a plurality of pixel electrodes, and a plurality of switching devices, and an opposed substrate holding a liquid crystal in cooperation with the device substrate; a voltage detector that when brought into contact with a display surface of the liquid-crystal display, detects pulses, which are applied consecutively to the scan electrodes and data electrodes, through electrostatic coupling between the detector and the scan electrodes or between the detector and the data electrodes and that outputs a detected signal; and a position detector for detecting a contact position of the detector on the basis of the detected signal. Herein, the device substrate is situated on the side of the observer of the display. The positions of data electrodes lying in the vicinity of a stylus are detected during a data electrode position detection period defined as a period during which no pulses are applied to scan electrodes. Positions of scan electrodes lying in the vicinity of the stylus are identified by detecting display scanning pulses that are applied consecutively to a plurality of scan electrodes in order to cause the switching devices to conduct consecutively during a display data writing period.