International Business Machines Corporation

Yasuhiro Kimura

Satoru Nishi

Yoichi Taira

Hiroshi Yamashita

Tatsuo Uchida

Mikio Kurihara

Hajime Nakamura

Toshihiko Yoshida

Yoshihiro Katsu

Haruhiro Matino

Satoshi Tsuji

Takahiro Onodera

Sueoka Kuniaki

In each pixel region of a liquid crystal TFT array substrate, formed are an ITO transparent electrode , a gate line , a data line , a TFT active device , an identification mark and the like. The identification mark is provided by forming a bar code made of silver on the gate line . Since the identification mark is formed within the pixel region , a transistor to be repaired can be surely identified, for example, by detecting the identification mark in a repair processing of the TFT array substrate. Furthermore, in an information processing apparatus for inputting figures and characters onto a screen using a laser pen, a locus of the laser pen can be accurately specified by specifying a position of a pixel region from an identification mark detected by the laser pen, and the figures and the characters input can be recognized minutely.

Liquid crystal panel, display device, identification mark detection device, detection display system, TFT array repair device and identification mark detection method

A liquid crystal display panel part group composed of a plurality of panel parts such as an array cell, a optical system sheet family, a light guide plate, a lamp reflector, and a lamp, and a liquid crystal display panel is enveloped in a film for laminating the parts. This film may be provided so as to cover the whole of the liquid crystal display panel part group and the film may have an opening. In order to adjust the positions of the parts, convex and concave portions are provided in the liquid crystal display panel parts.

LCD panel including plurality of display panel parts wrapped around by a thin plastic film envelope with an opening

The present invention relates to a driving method of a liquid crystal display device using an OCB (optically compensated birefringence) which realizes a wide view-field angle and high-speed response, and has an object of providing a driving method of a liquid crystal display device which method causes an OCB cell to transfer from a splay orientation state to a bend orientation state in short time. In a driving method of a liquid crystal display device using an OCB cell, gate on/off periods of a TFT are controlled at a start of a display operation, each pixel is caused to have bend orientation by a strong electric field that is generated between a gate electrode and a common electrode, and, at the same time, a voltage that is higher than that to generate an electric field necessary to maintain bend orientation is applied between a display electrode and the common electrode, to thereby effect transfer to bend orientation in short time.

Driving method of liquid crystal display device

To correct the dependency of the transmissivity/applied voltage characteristics on color, a computing circuit is provided for generating corrected gray scale data by performing an addition or subtraction of the gray scale level related to at least one color. A delay circuit delays the gray scale data for uncorrected colors to maintain synchronization between the gray scale signals of all colors.

Method for driving halftone display for a liquid crystal display

In order to display an image on a liquid crystal display at a constant image quality independently of a change of the length of the period for applying voltages with the same polarity to the liquid crystal, the length of one cycle of a horizontal synchronizing signal inputted to an LCD unit from an information processor is counted and the amplitude of data voltage and the center of the amplitude are corrected so that the amplitude of the data voltage to be applied to the liquid crystal increases and a correction value for the center of the amplitude increases as the length of the period for applying data voltages with the same polarity to the liquid crystal decreases in accordance with the length of one cycle of the horizontal synchronizing signal and whether to perform gate overlap scan. Thereby, the absolute values (V) of inter-electrode voltages after the TFT is turned off are equalized independently of the polarity of data voltage to be applied to the liquid crystal both for a relatively long period and for a relatively short period.

Correction of LCD drive voltage in dependence upon LCD switching element

The generation of flicker is prevented when the contrast of a displayed image is changed. The amplitude of the data voltage whose polarity is inverted at a timing synchronized with the display cycle of an image is changed based on the tone and the designed contrast. At the same time, the position (center) of 0 V relative to the amplitude of the data voltage is offset a larger amount as the contrast increases. This corrects a change V in voltage between the electrodes under the influence of the parasitic capacity of a TFT when the TFT is turned off, so that the voltage between the electrodes is also turned off despite the polarity of the data voltage applied to the liquid crystal, even when the designated contrast is relatively high and the amplitude of the data voltage is relatively small, and even when the designated contrast is relatively low and the amplitude of the data voltage is relatively large.

Growing community of inventors

Yamato, Japan

Yasuhiro Kimura