Kabushiki Kaisha Toshiba

Hoko Hirai

Masaki Miyatake

Susumu Kondo

Hajime Sato

Takanori Tsunashima

Hitoshi Hatoh

Yasuyuki Hanazawa

Yoshihiro Kinoshita

Yasushi Sasaki

Takeshi Yamamoto

Yoshiro Aoki

Akihiko Saitoh

Yuzo Hisatake

Akio Murayama

Shoichi Matsumoto

Masao Karube

Kazuo Nakamura

Kiyoshi Shohara

Masato Shoji

Kenshi Tsuchiya

Seiichi Sagi

In a flat panel display device in which driving circuits and the like are arranged on an array substrate, a technology to realize a compact size and a low cost of an external control circuit is disclosed. At least one pumping circuit included in the external control circuit is arranged on the array substrate, and an output side capacitor connected between an output portion of the pumping circuit and the ground GND and an input side capacitor of a clock input portion are arranged outside the array substrate.

Pumping circuit and flat panel display device

Arrangement of connection points of sampling switches to video bus lines within a signal line drive circuit is improved such that connection points of video buses (SVn to SVn ) supplied with positive-polarity video signals relative to a predetermined reference potential and video buses (SVp to SVp ) supplied with negative-polarity video signals to analog switches (SWn to SWn and SWp to SWp ) make substantially symmetric patterns in the extending direction of the video buses. Since the sum of lengths of connection wirings belonging to a switch pair and their total resistance value becomes substantially equal in all switch pairs, the effective vales of shift amounts in signal line potentials are substantially flattened. Therefore, here is provided a drive circuit built-in liquid crystal display device realizing a good imaging quality removing noise such as stripe-shaped imaging defects which may occur when video signals are supplied to analog switches through a plurality of video buses.

Liquid crystal display device

A multi-gradation liquid crystal display having dual display definition modes that can display both TV pictures and office automation images, both without flicker. Scanning electrodes extend in a first direction. Scanning and non-scanning voltages are selectively applied to the scanning electrodes. Signal electrodes extend in a second direction perpendicular to the first direction. First and second signal voltages are selectively applied to the signal electrodes. A layer of liquid crystal is sandwiched between the scanning and signal electrodes. Mode switching is provided for switching display between a first mode wherein an image is displayed by two-gradation pixels and a second mode wherein an image is displayed by three or more gradation pixels.

Multi-gradation liquid crystal display apparatus with dual display

In a liquid crystal display device in which a twisted nematic liquid crystal layer of positive dielectric anisotropy is sandwiched between two substrates fitted with electrodes and liquid crystal molecule orientation films, and in which the angle of intersection of the liquid crystal molecular alignment directions on the surfaces of the two substrates is .theta. (0.degree.&lt;.theta.&lt;90.degree.) and the cell twist angle is .phi. which is determined to give a uniform twist alignment to the liquid crystal layer by the tilt orientation on the two substrates, the liquid crystal molecule orientation films have a twist angle .omega. which is +.theta.+180.degree. or +.theta.-180.degree. when .phi. is +.theta., and which is -.theta.+180.degree. or -.theta.-180.degree. when .phi. is -.theta., in the state when a voltage applied to the liquid crystal layer is less than a threshold voltage.

Liquid crystal display device in which no sticking phenomenon occurs

A wiring 19 of a device directly detects a voltage from a plurality of scanning electrodes 1, a voltage detecting electrode 701 detects a voltage from a plurality of the scanning electrodes 1. A voltage variation component such as voltage distortion of the detected voltage which adversely affects on an image display is taken out, inverted, and negative fed back to the scanning electrode 1. A negative feedback loop provides the negative feedback of the voltage detected from and fed back to the scanning electrode 1, this therefore suppresses the disadvantageous voltage variation such as a distortion voltage which tends to arise in the scanning electrode 1.

In liquid crystal display system 10 which has a matrix arrangement of scanning electrode group 12 and data electrode group 13 and in which each electrode group is driven by a pulse like waveform, this is a liquid crystal display system in which a lower level region than the pulse wave peak value is formed in at least one of the rising or the falling portions of the pulse wave which drives at least one of the electrode groups. A liquid crystal display system with a uniform display with extremely little display non-uniformity can be obtained.

Liquid crystal display system

A liquid crystal display device has a birefringence control type liquid crystal display unit including a pair of substrates having electrodes on their first major surfaces and arranged with a predetermined distance therebetween such that the electrodes face each other, a liquid crystal material having a negative dielectric anisotropy, the material being disposed between the substrates, liquid-crystal molecules of the liquid crystal material being aligned vertically such that longitudinal axes of said molecules are inclined at a slight pretilt angle in respect of an axis vertical to the substrates when no voltage is applied to the electrodes, a pair of polarizing plates arranged on second major surfaces of the substrates, and a device circuit for driving the liquid crystal device in a multiplex manner. This device is characterized in that the liquid crystal material has a helical pitch in the state wherein the material is not disposed between the substrates, and the relationships of d.ltoreq.p and 50.ltoreq.f.multidot.d.sup.2 /p are satisfied, where d=the distance (.mu.m) between the substrates, p=the helical pitch of liquid crystal material disposed between the substrates, and f=the frame frequency (Hz) in the drive mode of the device.

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Yokohama, Japan

Hoko Hirai