Sharp Kabushiki Kaisha Corporation

Daisuke Suehiro

Daiji Kitagawa

Noriyuki Tanaka

Jin Miyazawa

Yousuke Nakamura

Tatsuhiko Suyama

Atsushi Aoki

A memory liquid crystal display including a liquid crystal panel with a built-in touch panel is provided with a state control circuit configured to switch a state of a pixel electrode between a floating state and a non-floating state. A pulse signal for touch detection is supplied to a common electrode in a touch detection period. The state control circuit changes the state of the pixel electrode from the non-floating state to the floating state before the start of the touch detection period, and changes the state of the pixel electrode from the floating state to the non-floating state after the end of the touch detection period.

Liquid crystal display with in-cell touch panel preventing display defect during touch detection

A liquid crystal panel is provided which is capable of performing displaying with sufficiently high quality while reducing power consumption. The liquid crystal panelincludes a plurality of pixel electrodes, a plurality of counter electrodes which are smaller in number and larger in individual size than the plurality of pixel electrodes, a liquid crystal layer disposed between the plurality of pixel electrodes and the plurality of counter electrodes, and a control unit configured to control a voltage applied to the plurality of pixel electrodes and a voltage applied to the plurality of counter electrodes. In a predetermined case, the control unit operates in a power saving operation mode in which the control unit performs control such that a fixed voltage is applied to the plurality of pixel electrodes and a voltage corresponding to an image signal is applied to the plurality of counter electrodes.

Liquid crystal panel

In a memory liquid crystal display including a liquid crystal panel with a built-in touch panel, a black voltage or a white voltage is provided to a pixel electrode in accordance with a value of binary data stored in a memory circuit, and a display voltage generation circuit changes voltage values of the black voltage and the white voltage in synchronization with a continuous pulse voltage for touch detection in a touch detection period so that an absolute value of a voltage between the pixel electrode and a common electrode is maintained at a constant magnitude in each pixel circuit throughout a period from a point in time immediately before the start of the touch detection period to a point in time immediately after the end of the touch detection period.

Growing community of inventors

Sakai, Japan

Daisuke Suehiro