Fujitsu Corporation

Tadahisa Yamaguchi

Kazuhiro Takahara

Masami Oda

Akira Yamamoto

Hisashi Yamaguchi

Munehiro Haraguchi

Fumitaka Asami

Takayuki Hoshiya

Tetsuo Aoki

A liquid crystal display has a liquid crystal layer, first and second electrodes, and a third electrode. The liquid crystal layer is inserted between the first and second electrodes to define liquid crystal cells. The third electrode is capacitively coupled with one of the first and second electrodes. A correction voltage for correcting distortion of a waveform for driving one of the first and second electrodes is applied to the third electrode, to keep an effective voltage applied to the liquid crystal cells unchanged and improve the display quality of the liquid crystal display. Therefore, the liquid crystal display of the present invention can correct distortion of a common voltage and prevent crosstalk.

Active matrix liquid crystal display and method of driving the same

In a driving device of an active matrix type liquid crystal display unit including a liquid crystal display panel, a scan driver, and a data driver, a data voltage controlling apparatus is provided to achieve digital multiple gray-scale levels with little flickering. The data voltage controlling apparatus supplies the data driver with a combination of two different data voltages picked up from a plurality of digital data voltages previously set. The combination of two different data voltages are, for example, a combination of different waveforms, a combination of negative level and positive level, and a combination of two different voltages having at least a voltage difference. Further, a division of T-V characteristics and an exchange of data voltages are carried out to reduce the flickering.

Apparatus for controlling data voltage of liquid crystal display unit to achieve multiple gray-scale

A data driver circuit of TFT-LCD having a plurality of power source voltage terminals with different voltage levels, an output terminal for providing a voltage to the TFT-LCD, a plurality of analog switches with load resistances provided between one of the source voltage terminals and the output terminal and having a switching terminal, and a voltage selection circuit for transmitting an ON signal to a selected one or more of the respective switching terminals of the analog switches. When an individual analog switch is turned ON, the corresponding source voltage value is supplied to the output terminal of the driver circuit and when two or more analog switches are selectively turned on, a combination of the voltage levels of the respective source voltage is associated with those switches which are turned ON is produced as the driver circuit output voltage, thereby affording a greater number of gray levels as the driver circuit output voltage levels than the number of power source voltage levels.

Data driver circuit of liquid crystal display for achieving digital

Growing community of inventors

Kawasaki, Japan

Tadahisa Yamaguchi