Matsushita Electric Industrial Co., Ltd.

Toshiba Matsushita Display Technology Co., Ltd.

Katsuji Hattori

Shoichi Ishihara

Yoshinori Tanaka

Kenji Nakao

Tsuyoshi Uemura

Katsumi Adachi

Hirofumi Kubota

Masakazu Fukai

Mika Nakamura

Shin-ichiro Hatta

Keisuke Tsuda

Akio Moriyama

Junichi Kobayashi

Hirofumi Wakemoto

Kiyohiro Kawasaki

Tsutomu Tanaka

Seiichi Nagata

Hiroyuki Serizawa

Yoshinobu Tsujimoto

Yukio Numata

Akira Kurozuka

Satoshi Takayama

Hiroyuki Takewa

Osamu Yamamoto

Yoneharu Takubo

Hiroshi Yamazoe

Hiroshi Satani

Shuichi Obata

Kazue Sato

Tsuneo Tanaka

Katsuaki Satoh

Tadashi Tamura

Komei Asai

Kosaku Murata

Hirotoshi Niguchi

Youichi Kimura

Yasuhiro Nishizawa

Mituhiko Serikawa

A method for providing a high-response and wide-viewing-angle liquid crystal panel capable of causing a transition of liquid crystal, called the OCB mode, into a bend configuration in a short time, by providing a period in which a potential difference higher than that in a normal image display period is continuously applied between gate lines and opposing electrodes or between pixel electrodes and the opposing electrodes of a liquid crystal panel.

Driving technique for activating liquid crystal device

There are disclosed methods for driving liquid crystal display apparatuses for certainly completing in a short time to performing a transition of liquid crystal molecules to a displayable alignment in liquid crystal display apparatuses such that an initial alignment of the liquid crystal molecules is different from the displayable alignment, typically an optically compensated bend mode liquid crystal display apparatus. A voltage is applied to a liquid crystal layer until display area in the liquid crystal layer is transformed to the displayable alignment. After the completion of the transition, a backlight is switched on to sift to a display-driving mode. In order to complete the transition in a short time, voltage pulse under the conditions (such as a frequency and a voltage value) determined in accordance with a temperature of a liquid crystal panel is applied to the liquid crystal layer.

Liquid crystal display apparatus and method for driving the same

Before starting the regular display in a liquid crystal display device of the bend alignment type, it is necessary to transition all the pixel regions in the entire display portion uniformly from splay alignment into bend alignment. However, conventionally, when applying a simple ac voltage, the transition sometimes does not take place, and when it does take place, the transition time is very long, and display defects due to alignment defects tend to occur. In the method for driving a liquid crystal display device with OCB cells according to the present invention, a step of applying between an electrodeand a pixel electrodean ac voltage superimposed with a bias voltage, and a step of applying zero voltage or a low voltage to the substrates are repeated in alternation preceding the begin of the regular display operation and the regular display operation is carried out after all pixels have transitioned into bend alignment.

Liquid crystal display with method for OCB splay-bend transition

To provide a high-response and wide-viewing-angle liquid crystal panel capable of causing a transition of liquid crystal, which is called the OCB mode, into a bend configuration in a short time, there is provided a period in which a potential difference higher than that in a normal image display period is continuously applied between gate lines and opposing electrodes or between pixel electrodes and the opposing electrodes of the liquid crystal panel. Also, ingenuities are exercised on the period in which the potential difference is continuously applied between them and on the structure of picture elements.

A liquid crystal display device having a pair of substrates; a liquid crystal layer disposed between the substrates; and a phase compensator arranged on an outer side of the substrates; wherein, when no voltage is applied, the liquid crystal layer, which has been subjected to a parallel alignment process, is in splay alignment, in which pretilt angles of the liquid crystal at an upper and at a lower boundary of the liquid crystal layer have opposite signs; wherein, before liquid crystal display driving, an initialization process is performed, in which the alignment of the liquid crystal layer is transitioned from splay alignment to bend alignment by application of a voltage; and wherein the liquid crystal display driving is performed in the bend alignment attained by this initialization; including at least one region outside the display pixels where the liquid crystal layer thickness is smaller than inside the display pixels, and that an electric field caused by the application of said voltage, applied to the liquid crystal layer, is larger in this region than in the pixels.

An active matrix type liquid crystal display composed of a liquid crystal cell is described. In the liquid crystal cell , liquid crystals at the upper and lower interfaces of a liquid crystal layer inserted between an array substrate having pixel electrodes and an opposed substrate having an opposed electrode have pretilt angles opposite to each other in a positive/negative sense and are aligned in parallel with each other, forming a spray alignment. This liquid crystal display performs displaying by bend-aligning such a liquid crystal cell . The pixel electrodes are formed on a flattening film for covering switching elements or wiring electrodes flat. With this arrangement, a spray to bend alignment transition can be reliably, easily caused in a short time within the liquid crystal cell pixels, so that an OCB mode liquid crystal display free from alignment defects and having high picture quality can be achieved.

Liquid crystal display and method of manufacture

An active matrix liquid crystal display device having a liquid crystal cell including an army substrate provided with a pixel electrode, a signal electrode line, and a gate electrode line and an opposing substrate provided with a common electrode, in which pretilt angles of liquid crystal at upper and lower interfaces of a liquid crystal layer disposed between the army substrate and the opposing substrate have opposite signs having splay alignment formed by parallel alignment process while no voltage is applied. The active matrix liquid crystal display device is subjected to an initialization process for transitioning the splay alignment to bend alignment by application of voltage before liquid crystal display driving and adapted to perform the liquid crystal display driving in the bend alignment. In addition the pixel electrode is provided with a protrusion at a periphery thereof in a plane parallel to a plane defined by an upper surface of the array substrate, and in a region where the protrusion does not overlap with the signal electrode line and the gate electrode line in a vertical direction relative to the, and voltage is applied continuously or intermittently applied to the pixel electrode and the common electrode.

OCB liquid crystal display device having pixel protrusions

In a liquid crystal display element comprising at least one substrate and a liquid crystal layer, a different orientation direction area of an orientation direction locally different from an orientation direction of the other area is present.

Liquid crystal display element with zigzag data or scan lines adjacent zigzag edged pixel electrodes

Liquid crystal display device and method for manufacturing the same

There are disclosed methods for driving liquid crystal display apparatuses for certainly completing in a short time to performing a transition of liquid crystal molecules to a displayable alignment in liquid crystal display apparatuses such that an initial alignment of the liquid crystal molecules is different from the displayable alignment, typically an optically compensated bend mode liquid crystal display apparatus. A voltage is applied to a liquid crystal layer until display area in the liquid crystal layer is transformed to the displayable alignment. After the completion of the transition, a backlight is switched on to shift to a display-driving mode. In order to complete the transition in a short time, voltage pulse under the conditions (such as a frequency and a voltage value) determined in accordance with a temperature of a liquid crystal panel is applied to the liquid crystal layer.

A liquid crystal display device having a pixel electrode, a counter electrode, and a liquid crystal between the electrodes. Liquid crystal molecules in contact or near the respective opposed surfaces of the electrodes have specified pretilt angles as a result of the conditioning of those surfaces. When no voltage is applied, the liquid crystal is in a splay alignment state; applying voltage prior to image display causes a transition of transformation of the splay alignment state to a bend alignment state; image display is carried out under the bend alignment state. Transition from the splay alignment state to the bend alignment state is promoted by having a large pretilt angle domain formed on at least one of the electrode surfaces causing a larger pretilt angle of liquid crystal molecules than is present in a region surrounding the large pretilt angle domain.

Liquid crystal display device and associated fabrication method

An active matrix type of twisted nematic liquid crystal display is provided with a lower alignment layer rubbed in rubbing directions RD3, RD4 opposite to each other, an upper alignment layer rubbed in rubbing directions RD5, RD6 opposite to each other, a liquid crystal layer arranged between the lower and upper alignment layers and filled with liquid crystal molecules set in a nematic liquid crystal phase, a pixel electrode and a common electrode for inducing a vertical electric field in the liquid crystal layer, and a source line and gate line driving a switching device for applying an electric potential to the pixel electrode. The rubbing direction on the substrate with the switching device is at an angle of 1.degree.-44.degree. to either the source or gate line. In this case, major axes of a group of liquid crystal molecules arranged above the pixel electrode are twisted in a clockwise direction, and major axes of other group of liquid crystal molecules are twisted in a counterclockwise direction.

Active matrix twisted nematic liquid crystal display with rubbing

Erasable optical disk media basically comprise a double layer structure composed of a thermal expansion layer formed of an organic dye and a binder, and a retention layer of metal. In the recording process, the thermal expansion layer is heated to form a dome-like pit in the retention layer. The reproducing process is performed by reading differences in reflectivity from the pit and an area surrounding the pit. In the erasing process, the retention layer including the pit is heated to flatten the same under the tensile stress (residual stress) acting on the thermal expansion layer. The pit size is kept in a stable condition during the recording and reproducing processes, while the erasing can be performed completely without leaving partly erased traces. The erasable optical disk media of the foregoing construction are highly durable and resistant to heat.

Erasable optical disk media and method of recording/erasing the same

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Takarazuka, Japan

Katsuji Hattori