Hitachi, Ltd.

Hitachi Displays, Ltd.

Hitachi Device Engineering Co., Ltd.

Panasonic Liquid Crystal Display Co., Ltd.

Hiroyuki Takahashi

Katsuhiko Yarita

Takayuki Iura

Takashi Tsuyuki

Toshio Miyazawa

Mitsuru Goto

Shinji Yasukawa

Hitoshi Komeno

Kazunari Kurokawa

Nobuhiko Hosotani

Shinya Hashimoto

Toshimitsu Matsudo

Akira Ogura

Takahiro Fujioka

Shigeo Adachi

Youichi Ooki

Takahiro Yamada

Akifumi Kishino

Yoshio Sugaya

A liquid crystal display device included in a compact portable device reduces burden imposed on a driver circuit for driving counter electrodes and produces images having preferable quality. The liquid crystal display device includes liquid display element and liquid crystal driving circuit. The liquid crystal driving circuit drives two counter electrode signal lines during one scanning period for driving one scanning signal line. Counter signals having different polarities are supplied to the two counter signal lines. Since the number of pixels operated by one counter electrode signal line is decreased to half, burden imposed during drive of counter electrodes is reduced.

Liquid crystal display device

Provided is a drive circuit low in power consumption and high in display quality for a liquid crystal display device that is used in a small-sized portable device. The liquid crystal display device includes liquid crystal display elements and a liquid crystal driving circuit. The liquid crystal driving circuit is mounted to one of the four sides of a liquid crystal display panel, and is capable of outputting two-system counter electrode voltages. A variable resistor circuit having a resistance value which is variably adjusted by a register is used to correct and output a gray scale voltage according to a position of a relevant scanning signal line. Equalization is also performed by short-circuiting two counter electrode signal lines.

The present invention provides a liquid crystal display device used in miniaturized portable equipment which exhibits favorable display quality while decreasing a load applied to a driver circuit which supplies a video signal line to pixel electrodes. In a liquid crystal display device which includes liquid crystal display elements and a liquid crystal driving circuit, a boosting circuit is provided to a pixel portion. The boosting circuit, after writing a video signal in a pixel electrode and one electrode of a boosting capacitance, brings the pixel electrode into a floating state. Then, by applying the video signal to another electrode of the boosting capacitance, a voltage of the pixel electrode is boosted or dropped.

The present invention provides a display device which, in a region on which a semiconductor chip is mounted, can narrow the distance between neighboring line layers and, at the same time, can increase an area of terminals which are connected with bump electrodes of the semiconductor chip. In a display device which includes a substrate having a display part and a peripheral portion, and a semiconductor chip which is mounted on the peripheral portion of the substrate, the semiconductor chip includes a first bump electrode, the substrate includes a first line, a second line which is arranged adjacent to the first line, an insulation film which covers the first line and the second line, a first contact hole which is formed in the insulation film, and a first terminal which is connected to the first line via the first contact hole, the first bump electrode is connected with the first terminal, the second line is electrically insulated from the first terminal, and the first terminal is arranged to overlap the second line by way of the insulation film as viewed in a plan view.

Display device comprising a semiconductor chip including a first terminal which overlaps a first and second line, the first terminal connected to the first line and overlapping and insulated from the second line

An image display device includes a first display panel having a substrate with first scanning lines, first signal lines which intersect the first scanning lines, and first switching elements, a second display panel having another substrate with second scanning lines, second signal lines which intersect the second scanning lines, and second switching elements, and a flexible printed circuit board connecting the first display panel with the second display panel. The image display device drives the first display panel in a line inversion mode when only the first display panel displays images, drives the second display panel in a frame inversion mode when only the second display panel displays images, and drives the first display panel and the second display panel in the line inversion mode when both of the first display panel and second display panel display images.

Display device

A display device of the present invention has a drain driver mounted to a display substrate and having a gate driver and a controller therein, and also has a power source mounted to a flexible printed board and supplying a power voltage to the gate driver. The wiring of a common control signal outputted from the controller and commonly used in control of the gate driver and the power source is formed on the display substrate so that the number of pads for connecting the display substrate and the flexible printed board is reduced. Thus, the construction of the flexible printed board is simplified, and the entire display device can be made compact.

Display device having driving circuit

Let a drive circuit chip shrink in outer shape size to thereby enable miniaturization of a display device as a whole. The display device is equipped with a plurality of pixels disposed on a substrate in the form of a matrix and more than one drive circuit chip GDR as mounted on the substrate for causing these pixels to perform a display operation, wherein the drive circuit chip GDR has a plurality of output terminals OT for connection to output wiring lines GL formed on the substrate and a plurality of dummy terminals DT disposed adjacent to one another, and wherein at least one of the output wiring lines GL connected to the output terminals OT is not connected to any one of the dummy terminals DT and is disposed to pass through between the mutually adjacent dummy terminals DT.

An integral-type liquid crystal display module has a first display panel and a second display panel, and it can use a display panel of high resolution as the second display panel. The display device includes a first display panel, a second display panel, and a first flexible printed circuit board which connects the first display panel and the second display panel. The first display panel includes a display drive unit. Video lines of the second display panel are connected with the display drive unit through connection lines for video lines of the first flexible printed circuit board. Further, the second display panel includes a scanning line drive unit which supplies drive voltages to scanning lines of the second display panel.

A liquid crystal display device with both functions of transmission-mode display and reflection-mode display is capable of providing an improved display quality in each display mode, to thereby obtain on-screen display images of high quality in either one of the display modes. The liquid crystal display device includes a scan signal line drive circuit operable to apply a scan signal to a number of scan signal lines, an image/video signal line drive circuit which applies an image signal to a number of image signal lines, and a power supply circuit for supplying necessary voltages to the scan signal line drive circuit and image signal line drive circuit. The power supply circuit includes a counter electrode voltage generation circuit for selecting a voltage optimized for a respective display mode of the transmission mode and the reflection mode to thereby apply the selected voltage to a counter electrode.

An image display device includes a first display device and a second display device, which is constituted of a smaller number of signal lines than that of the first display device. The signal lines of both display devices are driven by a common drive circuit. The display of images is alternatively or simultaneously performed using these two display devices. To achieve a suppression of vertical smear and low power consumption in this type of device, the images are displayed in an N-line (N being an integer of 1 or more) inversion drive mode when the display is performed on only the first display device and when the display is performed on both of the first display device and the second display device, while the images are displayed in a frame inversion drive mode when the display is performed only on the second display device.

An image display device is capable of preventing the occurrence of flickers on a display screen by automatically adjusting a common voltage applied to common electrodes without providing light receiving elements. A plurality of dummy pixels which are arranged in the periphery of an image display part include pixel electrodes. A potential difference is detected between a voltage of the pixel electrodes of the dummy pixels to which a gray scale voltage of positive polarity is written and a common voltage applied to the common electrodes, a potential difference is detected between a voltage of the pixel electrodes of the dummy pixels to which a gray scale voltage of negative polarity is written and the common voltage, and the common electrodes are controlled so as to make the first potential difference and the second potential difference equal to each other.

Image display device

A liquid crystal display device comprising, a liquid crystal panel having parallel provision of a plurality of common electrodes COM extending in a first direction on one of a pair of substrates with a liquid crystal layer interposed therebetween and parallel provision of a plurality of segment electrodes SEG extending in a second direction crossing in the first direction on the other of the pair of substrates, a common driver for applying a scan signal(s) to the plurality of common electrodes COM, and a segment driver for applying to each of the plurality of segment electrodes SEG a pulse-width-modulated data signal voltage corresponding to display data, wherein the segment driver is operable upon switching of the pulse-width-modulated data signal voltage input to the segment electrode SEG to temporarily output to the segment electrode a voltage which is substantially equal to a non-select voltage of the common electrodes COM.

The present invention suppresses the increase of consumptive electricity derived from the alternation timing driving of a passive matrix type liquid crystal display device such as an STN system or the like. According to the present invention, the liquid crystal display device which is driven by applying selection voltages to common electrodes during a scanning period of the common electrodes and by applying non-selection voltages during other periods to the common electrodes includes a switching circuit which temporarily short-circuits the common electrode n and the common electrode m during a period shifting from the scanning period of the common electrode n to the scanning period of the common electrode m which succeeds the scanning period of the common electrode n, and makes use of the charge stored in the common electrode n by the application of the selection voltage during the scanning period of the common electrode n for charging the common electrode m.

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Funabashi, Japan

Hiroyuki Takahashi