Fujitsu Corporation

Sharp Kabushiki Kaisha Corporation

Ken-ichi Nakabayashi

Hiroshi Murakami

Keizo Morita

Masafumi Itokazu

Mitsuharu Nakazawa

Akira Yamamoto

Kazuhiro Takahara

Munehiro Haraguchi

Masami Oda

Koji Yoshioka

Michiya Oura

A display device has a display section having scanning lines, and first and second scanning drivers having output lines for supplying scanning signals to the two ends of the scanning lines in the display section. When the potential of at least one of the output lines of the first or second scanning driver is fixed or unfixed due to an error in the first or second scanning driver, the output line at the fixed or unfixed potential is disconnected from the corresponding scanning line in the display section.

Display device and driving method of the same

Disclosed is a liquid-crystal drive circuit having a simple configuration and being not susceptible to the characteristic of a device. The liquid-crystal drive circuit includes an auxiliary capacitor, applies a first voltage to a driving buffer, temporarily accumulates an output voltage of the driving buffer in the auxiliary capacitor, applies a voltage produced by subtracting the potential at the auxiliary capacitor from a second voltage to the driving buffer, and applies an output of the driving buffer onto a data bus.

Drive circuit for liquid-crystal displays and liquid-crystal display including drive circuits

An active-matrix LCD causes no cross-talk even if the capacitance between a given cell and adjacent data lines is large. The LCD has a liquid crystal panel which has data lines arranged in parallel with one another, scan lines arranged orthogonally to the data lines, and liquid crystal cells arranged at the intersections of the data and scan lines, respectively. Each of the cells has a cell electrode and a switching device that is arranged between and connected to the cell electrode and a corresponding one of the data lines. The conduction of the switching device is controlled in response to a scan pulse applied to a corresponding one of the scan lines. The LCD also has a data driver for applying data signals to the data lines, respectively, so that the data signals are written to corresponding ones of the cells, and a scan driver for applying the scan pulse sequentially to the scan lines. The data driver applies positive and negative signals that are opposite to each other with respect to a reference level, to each of the data lines within the period of the scan pulse, to zero an effective voltage applied to each data line. As a result, a voltage sustained by any cell to which data has been written is not affected by voltages successively applied to a data line to which the cell is connected and a data line to which the cell is capacitively connected.

Active-matrix liquid crystal display and method of driving same

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.

Liquid-crystal display having the capability of a tablet

Growing community of inventors

Kawasaki, Japan

Ken-ichi Nakabayashi