Hosiden Electronics Co., Ltd.

Hosiden Corporation

Tpo Hong Kong Holding Limited

Koninklijke Philips Corporation N.v.

Nippon Telegraph and Telephone Corporation

E Ink Corporation

Masaru Yasui

Takeo Kamiya

Yasuhiro Ukai

Satoshi Hirano

Shigeo Aoki

Shuji Hagino

Mark Thomas Johnson

Karl Raymond Amundson

Yukio Takahashi

Robert Waverly Zehner

Keitaro Yamashita

Guofu Zhou

Tomihisa Sunata

Masahide Inoue

Junichi Tamamura

Tadaaki Masumori

Teizo Yukawa

Tadamichi Kawada

Shuzo Isogami

Masakatsu Yamashita

Tadao Nakamura

Tatsuo Nagayoshi

Takeo Kamiya, Deceased

Akira Kumiya, Legal Representative

Noriyoshi Uenishi

Yuko Hori

Akihiko Miyazaki

Kenji Hanzawa

Masanori Hosomichi

Susumu Hirao

Taisuke Miyazu

Electrophoretic display units () comprising pixels () situated between common electrodes () and pixel electrodes () need, for shortening the total image update times, increased driving voltages across the pixels () which endanger transistors () coupled to the pixel electrodes (). These increased driving voltage (V) to the common electrode (). To protect the transistors () against these increased driving voltages, a setting signal (S, S) is supplied to the pixel electrode () via the transistor () for reducing a voltage across the pixel () resulting from a transition in the alternating voltage signal (V). During driving frame periods (F) data pulses (D, D, D, D, D, D) are supplied, and during setting frame periods (F), the setting signals (S, S) are supplied.

Electrophoretic display unit

It is an object to provide an active matrix liquid crystal display device capable of effectively eliminating flicker with a simple structure. An active matrix liquid crystal display device has a plurality of gate lines, a plurality of source busses extending orthogonal to the gate lines, a plurality of liquid crystal elements provided in intersections of the gate lines with the source busses and, as a whole, disposed in matrix form, the liquid crystal devices being connected between a pixel electrode and an opposite electrode connected to a first bus line in a floating condition, a plurality of control circuits provided in relation with the liquid crystal element, the control circuits having: first and second transistors, of which gates are connected to the gate lines respectively, arranged in series between the source busses and the pixel electrode, a third transistor provided between a midpoint node of the first and second transistors and a second bus line to serve as a switch, the second bus line being identical in potential to the first bus line and being electrically isolated from the first bus line, and a fourth transistor connected in parallel with the liquid crystal elements between the pixel electrode and the opposite electrode to detect drain voltage.

Active matrix liquid crystal display device having a flicker eliminating circuit

An image display device having a voltage supplying device generating a first changing voltage for setting a transistor to an on-state and a second changing voltage for setting a transistor to an off-state to operate so as to establish a first supply mode, a second supply mode and a third supply mode to a plurality of gate buses for determining the corrected common electrode voltage.

Image display device with circuits to compensate voltage drop in the common electrode for active matrix liquid crystal displays

In an RGBW-type liquid crystal display device, luminance is improved by the addition of W sub-pixels while an image is displayed without any change in chromaticity of halftones. Digital corrected values of red, green and blue are obtained by adding a predetermined digital value for driving a W sub-pixel to each of RGB digital values which correspond respectively to pixels of an acquired image. A converting calculation is effected on the digital corrected values such that the ratio of these digital corrected values for red, green and blue is made equal to the ratio of the red, green and blue digital values corresponding to the pixels of said acquired image. The RGBW sub-pixels are driven with the converted values and the predetermined digital value of driving W sub-pixel to thereby display an image.

Liquid crystal display apparatus

This invention relates to an RGBW-typed LCD wherein a proper luminous image can be displayed according to a predetermined calculation with a decoder where some predetermined calculation formulas are embedded. Further, not only RGBW image display but also RGW image display can be used by a predetermined controlling signal.

Liquid crystal display device

The device has an LCD panel , a digital circuit and an analog circuit which generate display signals to be supplied to the LCD panel , and has functions of normal mode and stand-by mode in a status where electric power is supplied from a power source . In the normal mode, a multivalued display signal which can represent gradation levels is generated and supplied to the LCD panel , while in the stand-by mode, a binary display signal which does not represent gradation levels is generated and supplied to the LCD panel

LCD device

In a common potential stabilizing active matrix liquid crystal display device, the common potential is detected via a common potential detecting terminal provided at the perimeter of the common electrode, the detected potential is compared with a reference potential and the difference is amplified by an amplifier and is negatively fed back to a common potential supply terminal provided at the perimeter of the common electrode.

Liquid crystal display device with stabilized common potential

Liquid crystal display AC-drive method and liquid crystal display using

In the case of erasing a display on an active matrix type liquid crystal display which has a source bus drive circuit (16) and a gate bus drive circuit (17), pixel signals for turning OFF pixels of one row are applied to the source bus drive circuit, and at the same time, a clear signal (CL) is provided to the gate bus drive circuit (17), from which a voltage for turning ON transistors (13) provided in association with the respective pixels is applied to gate buses (15.sub.l through 15.sub.m) all at once. A power holding circuit (22) is provided for holding power of an operating power supply (V.sub.1) for a predetermined period of time after the power supply of the display is turned OFF, and a voltage drop detector (24) is provided for detecting the turning OFF of said power supply, and its detection signal is used to produce the clear signal (CL), which is provided to the gate bus drive circuit (17). The gate bus drive circuit responds to the clear signal to apply the voltage for turning ON the transistors (13) of the respective pixels to the gate buses all at once, thereby erasing the display in a short time after the turning OFF of the power supply.

Method and circuit for erasing a liquid crystal display

An input analog image signal is sampled by first and second A/D converters, using first and second sampling clocks of the same period, to obtain digital gradation data. In the case of a double definition display mode, the first and second sampling clocks are made 180.degree. out of phase with each other and the output of the first A/D converter is delayed for one-half period, by which its timing is brought into agreement with that of the output of the second A/D converter, thus obtaining a pair of digital gradation data. In the case of a standard definition display mode, the first and second sampling clocks of the same phase are used to obtain the outputs of the first and second A/D converters as a pair of digital gradation data. The pair of digital gradation data Da and Db is converted by a signal processing part into a pair of analog gradation data Aa and Ab, which is subjected to a serial-to-parallel conversion by a source driver to be supplied in parallel to data lines. In the double definition display mode the gate driver sequentially drives odd-numbered row lines in odd-numbered frames and even-numbered row lines in even-numbered frames. In the standard definition display mode every two adjacent row lines are simultaneously driven in a sequential order.

Liquid crystal display device capable of selecting display definition

One end portion of each pixel electrode is extended under a gate insulating film underlying the neighboring gate bus and defines an additional capacitance region. The extended portion of the pixel electrode is divided into a plurality of comb-tooth-like electrodes, each defining divided additional capacitors. One of the comb-tooth-like electrodes is separated by a gap from the pixel electrode, and first and second electrodes for laser welding use are formed on the comb-tooth-like electrode and the pixel electrode facing each other across the gap. The first and second electrodes form series-connected first and second capacitances for laser welding use between them and a third electrode for laser welding use formed above them with a gate insulating film interposed therebetween. When one of the divided additional capacitors connected to the pixel electrode is bad in insulation, the defective one of the divided additional capacitors is cut off and the first and second capacitances are caused to short by welding, whereby the total additional capacitance can be held substantially constant.

Active matrix display device having divided additional capacitors

A planar display device is disclosed, which comprises a plurality of display elements in rows and columns, row drive lines each commonly connected to two adjacent rows of display elements and column drive lines are provided in pairs each for each column of display elements, every other one of the display elements in a column being connected to one of the pair of column drive lines, and the other display elements in the column being connected to the other column drive lines in the pair. Each of the display elements is selectively activated by the row and column drive lines connected thereto.

Planar display device

In a multi-gradation display method and apparatus by which a display signal formed by a picture element signal of any one of the levels of N gradations (where N is an integer equal to or greater than 3) is displayed on a display panel in which each picture element produces a two-gradation display, one frame is composed of (N-1) fields, and accordingly each picture element is supplied with a binary signal (N-1) times for each frame, and the binary signal is given one of its values by a number of times corresponding to the level value of the input picture element signal and the other value by the remaining number of times.

Method and apparatus for multi-gradation display

In a liquid crystal display device, display electrodes are arranged in a matrix form, gate and source buses are provided for each row and column of the display electrodes, and a pixel driving composite transistor is connected between each display electrode and the gate and source buses for driving the display electrode. Source-drain electrode pairs opposite in the direction of arrangement, which are equal in number, are provided for each transistor, and a common semiconductor layer and a common gate electrode are provided for all the source and drain electrodes to form an even number of thin film transistors connected in parallel to one another, thereby constituting the composite transistor for driving a pixel.

Pixel transistor free of parasitic capacitance fluctuations from

A transmitting type display device is disclosed, which comprises a transmitting type display panel to provide a display on the front surface, a light source for producing light illuminating the back surface of the transmitting type display and a brightness controller for controlling the intensity of light from the light source. The device comprises an ambient light detector disposed near the transmitting type display panel for detecting the intensity of ambient light incident on the display surface of the transmitting type display panel, and the brightness controller for controlling the light source according to the detection output of the ambient light detector such that the intensity of light from the light source to the transmitting type display panel is increased with an increase of the detected light intensity.

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Kobe, Japan

Masaru Yasui