Sharp Kabushiki Kaisha Corporation

Tatsuhiko Suyama

Noriyuki Tanaka

Norio Ohmura

Kouji Kumada

Takuya Sone

Kentaroh Uemura

Yousuke Nakamura

Kazuo Nakamura

Daiji Kitagawa

Jin Miyazawa

Masaaki Nishio

Teruhisa Masui

Makoto Yokoyama

Kazuki Takahashi

Atsushi Aoki

Hongbing Weng

Daisuke Suehiro

A display device includes a display panel including: a first subpixel including a first light-emitting element; and a second subpixel adjacent to the first subpixel and including a second light-emitting element. The display device includes a circuit unit calculating a degradation amount of the first light-emitting element in accordance with a light-emission state of the second light-emitting element, and calculating a compensation value of the first light-emitting element in accordance with the calculated degradation amount of the first light-emitting element.

Display device and method for driving display device

A display device is provided with: a display portion including a plurality of scanning lines, a plurality of data lines, and a plurality of pixel circuits; a scanning line drive circuit; and a data line drive circuit. The level of a data voltage applied to the data line decreases when a frame frequency is switched higher, and increases when the frame frequency is switched lower. This can prevent a display flicker when the frame frequency is switched. The level of the data voltage may change when the frame frequency is switched, and may return to its initial level over a plurality of frame periods. The timing of the control signal used to drive the display portion may change in accordance with the frame frequency to cause the length of the charging period of the pixel circuit to change in accordance with the frame frequency.

Display device and method for driving same

A liquid crystal panel is provided which is capable of performing displaying with sufficiently high quality while reducing power consumption. The liquid crystal panelincludes a plurality of pixel electrodes, a plurality of counter electrodes which are smaller in number and larger in individual size than the plurality of pixel electrodes, a liquid crystal layer disposed between the plurality of pixel electrodes and the plurality of counter electrodes, and a control unit configured to control a voltage applied to the plurality of pixel electrodes and a voltage applied to the plurality of counter electrodes. In a predetermined case, the control unit operates in a power saving operation mode in which the control unit performs control such that a fixed voltage is applied to the plurality of pixel electrodes and a voltage corresponding to an image signal is applied to the plurality of counter electrodes.

Liquid crystal panel

The power consumption of an apparatus including a touch panel is reduced. In a touch panel control device () including a sensor drive section () and a liquid crystal drive controller (), the sensor drive section () makes a detection sensitivity during a pause period lower than a detection sensitivity during an update period, the pause period being a period in which the liquid crystal drive controller () does not update the image that is displayed on a liquid crystal display panel (), the update period being a period in which the liquid crystal drive controller () updates the image that is displayed on the liquid crystal display panel ().

Touch panel control device and information processing apparatus

A display apparatus includes a source driver and a gate driver which drive a display section such that pixel signals are selectively supplied to a plurality of pixels provided in the display section. The display section includes a non-image visual recognition area, in which it is not possible for a visual recognizer to visually recognize an image to be displayed, and an image visual recognition area in which it is possible for the visual recognizer to visually recognize the image to be displayed. The source driver and the gate driver lower a driving rate which drives the non-image visual recognition area further than a driving rate which drives the image visual recognition area.

Display driving device and display apparatus

The present invention provides a data processing device connected with an intermission driving. The data processing device achieves a satisfactory power saving while ensuring a high level of display quality of the display device. Upon detection of non-data update in a frame buffer, the host calculates a next refreshing timing based on driving information obtained from a liquid crystal display device (LCD), sets a timer for a timeout after a length of time representing the calculated result, and then the host and the LCD shift to Intermission State. Thereafter, when the timer times out to bring the host back to Normal State and a data update at the frame buffer is detected, data for refreshing an display image in the LCD is transferred from the host to the LCD. If the amount of time representing the calculated result is longer than a predetermined baseline, a shift is made to Intermission Statewhich provides greater power saving than Intermission State

Data processing device connected with display device and control method of display device

In a liquid crystal display device, a drive unit is controlled in a direction of eliminating a polarity bias of a data voltage corresponding to image data at a point of time when a refresh signal for updating an image displayed on a display unit by periodical refreshment or forced refreshment is generated, and the polarity bias is obtained for each of subsequent frame periods. In this manner, not only the polarity bias after the point of time when the refresh signal is generated is obtained so that the polarity bias at the point of time when the refresh signal is generated is eliminated, but also the polarity bias is repeatedly obtained in the same way every time the refresh signal is generated, and accordingly, the polarity bias can be prevented from being increased.

Liquid crystal display device and method for driving same

When a SLEEPIN Command is inputted to the liquid crystal display device, the liquid crystal display device controls a source driver and a gate driver to generate an alternating current voltage and apply the generated alternating current voltage to a liquid crystal layer, in order to eliminate charge storage due to impurity ions distributed unevenly due to a polarity bias caused by a voltage applied to the liquid crystal layer until a point of time when the Command is inputted. In this manner, the liquid crystal display device shifts to a sleep period in a state where the charge storage due to the unevenly distributed impurity ions is eliminated. Therefore, when the liquid crystal display device resumes from the sleep period, generation of an afterimage due to burn-in of liquid crystal and generation of a flicker due to deviation of an optimum common voltage do not occur.

There is provided a display device that is capable of suppressing occurrence of brightness drop which is caused by refresh of a display image during pause driving. In a normal driving mode, input image data (SsD) according to a continuous tone method is supplied to a source driver () through a data selector () as an image signal (SsD) for driver. On the other hand, in a low-frequency driving mode in which pause driving is performed, the input image data (SsD) is converted into dithered input image data (SsD) by a dithering processing circuit (), and is supplied to the source driver () through the data selector () as the image signal (SsD) for driver. A gradation of the dithered input image data (SsD) is represented in a pseudo manner by an area coverage modulation method by using two values of a maximum value and a minimum value that can be taken as the gradation value of the input image data (SsD).

In a liquid crystal display device, it is determined whether or not image data inputted from the outside has changed from image data of the previous frame by comparing those image data with respect to each line. As a result, when it is determined that the image data has changed, an entire screen is not rewritten, but image data from a top of a screen as a fixed position to a last line with the image data having changed are read from a frame memory and written into a pixel formation portion. Accordingly, of the screen for one frame, a screen from a top thereof to the last line where the image change has been detected is updated, and on subsequent lines, an image of the previous frame is continuously displayed.

Image display device

Provided are a liquid crystal display device and a driving method therefor that do not cause problems such as occurrence of flicker even when performing pause driving. When an off signal Soff instructing to turn off power is inputted, a polarity bias value W at the power-off is stored in a balance storage circuit. When the power is turned on again, the polarity bias value W is read from the balance storage circuit and provided to a balance control circuit. The balance control circuit starts insertion of a pause frame period to cancel out the polarity bias value W. By this, decrementing the polarity bias value W by '1' every insertion of a pause frame period is repeated. Then, at a point of time when the polarity bias value W becomes '0', insertion of a pause frame period is ceased and normal pause driving is performed.

Liquid crystal display device including display control circuitry configured to store a polarity bias value

Based on a REF/NREF signal coming from a REF/NREF determination circuit, a polarity bias calculation circuit updates a polarity bias count value Nb indicating a degree of a polarity bias of an applied voltage to a liquid crystal layer, and based on this polarity bias count value Nb, a bias movement determination circuit determines a moving direction of the polarity bias. Upon receiving an OFF signal Soff instructing OFF of the power supply, a balance control circuit controls a drive unit based on a result of the determination of the polarity bias moving direction and on the polarity bias count value Nb at a point of time when the OFF signal Soff is inputted so that the polarity bias can be resolved before a power supply is turned off.

Liquid-crystal display device and method for driving same

In a liquid crystal display device for performing pause driving, occurrence of flicker is effectively suppressed while an increase in power consumption is suppressed. When a frame in which an image signal (DAT) is inputted from an external portion without output of a request signal (RO) for requesting the external portion to input the image signal (DAT) is defined as a first input frame, a reversal driving control portion () sets the reversal driving technique in the first input frame to the column-reversal driving while setting the first input frame to a refresh frame defined as a first refresh frame, sets three frames subsequent to the first refresh frame to pause frames, sets a frame subsequent to the final pause frame to a refresh frame defined as a second refresh frame, and sets the reversal driving technique in the second refresh frame to the dot-reversal driving.

Provided is a liquid crystal display device capable of reliably reducing power consumption during pause drive by controlling the timing of performing refresh. When there is an image change in externally inputted RGB data, or when the number of consecutive pause frames reaches a predetermined value, if the number of immediately preceding pause frames is less than a threshold BCTH, image signal refresh is performed once, or if the number of pause frames is greater than or equal to the threshold BCTH, boost charge refresh is performed first, and then, the image signal refresh is performed. As a result, it is rendered possible to reduce flicker due to luminance reduction, and it is also rendered possible to eliminate the need to perform refresh consecutively even if the frequency of RGB data is high (e.g., 30 Hz) during pause drive.

In a liquid crystal display device for performing pause driving, occurrence of flicker is effectively suppressed while an increase in power consumption is suppressed. When an image change determination portion () detects an image change in a period from the previous refresh frame until generation of a predetermined number of times of pause frames, a reversal driving control portion () sets the next frame after a frame where an image change has been detected to a refresh frame where a reversal driving technique is a column-reversal driving. When the image change determination portion () does not detect an image change in the period from the previous refresh frame until generation of the predetermined number of times of pause frames, the reversal driving control portion () sets the next frame after the final pause frame to a refresh frame where a reversal driving technique is a dot-reversal driving.

Growing community of inventors

Osaka, Japan

Tatsuhiko Suyama