Sharp Kabushiki Kaisha Corporation

The Furukawa Electric Co., Ltd.

Kouji Kumada

Noriyuki Tanaka

Takashige Ohta

Toshihiro Yanagi

Tatsuhiko Suyama

Takuya Sone

Norio Ohmura

Kazuhiko Tsuda

Masahiro Shimizu

Hisakazu Nakamura

Haruhito Kagawa

Hitoshi Shimizu

Taketoshi Nakano

Akizumi Fujioka

Kazuki Takahashi

Daiji Kitagawa

Katsuya Mizukata

Jin Miyazawa

Moritaka Nakamura

Kentaroh Uemura

Yukihiro Nakahara

Hitoshi Kamezaki, Legal Representative

Masano Kamezaki, Legal Representative

Kazuhiro Maeda

Yutaka Takafuji

Hiromi Katoh

Akihiko Kasukawa

Norihiro Iwai

Ichiro Shiraki

Masaaki Nishio

Osamu Sasaki

Yoshihiko Katsuda

Yoshirou Kataoka

Yutaka Kamezaki

A display device () in accordance with an embodiment of the present invention includes: an LCD driving section () and an LCD controller () for causing an image based on an image signal to be displayed on an LCD (); and a CPU () for supplying an image signal to the LCD controller (), the LCD controller () being configured to supply, to the CPU (), a control signal that instructs the CPU () to supply an image signal, and the CPU () being configured to supply an image signal in a case where the CPU () receives a control signal.

Display device and control method

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.

Liquid crystal display device and method for driving same

The purpose of the present invention is to provide a display device in which the occurrence of the crosstalk can be suppressed. A display unit includes a display panel (), a storage unit (), a confirmation unit (), and a correction unit (). The display panel displays a synthetic image. The storage unit stores respective crosstalk levels set with respect to a plurality of areas () that the display panel has. The confirmation unit that confirms in which one of the plurality of areas a pixel exists that displays an image that a viewer is supposed to see, among the plurality of images contained in the synthetic image. The correction unit reads the crosstalk level corresponding to the area, among the plurality of areas, in which the confirmation unit confirms the pixel displaying the image that a viewer is supposed to see exist, from the storage unit, and corrects the gray scale level data of the pixel displaying the image that a viewer is supposed to see, by using the crosstalk level.

Display device

Provided is a display device capable of switching a refresh rate while suppressing deterioration in display quality and degradation in liquid crystal. In the case of switching the refresh rate from 60 Hz to 7.5 Hz, a transition period for gradually changing the refresh rate from 60 Hz to 7.5 Hz is provided between a 60-Hz period and a 7.5-Hz period. This transition period is configured by sequentially arraying a 30-Hz period, a 20-Hz period, a 15-Hz period, a 12-Hz period and a 10-Hz period from a start point of the transition period. Hence the refresh rate gradually changes from 60 Hz to 7.5 Hz sequentially through 30 Hz, 20 Hz, 15 Hz, 12 Hz and 10 Hz. The number of positive-polarity frames and the number of negative-polarity frames are respectively 20 in the whole of the transition period, and are equal to each other.

Display device and method for driving the same

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.

In a liquid crystal display device for performing pause driving, occurrence of flicker is effectively suppressed while an increase in power consumption is suppressed. A frame in which an image signal is inputted without requesting an external portion to input the image signal is set as a refresh frame by a reversal driving technique deciding portion. A pause frame counting portion counts the number of times of pause frames since the previous refresh frame as a count value. The comparison portion compares the count value with a previously set threshold. As a result, when the count value is not smaller than the threshold, the reversal driving technique deciding portion sets a reversal driving technique in the first input frame to dot-reversal driving. When the count value is smaller than the threshold, the reversal driving technique deciding portion sets a reversal driving technique in the first input frame to column-reversal driving.

An object of the present invention is to provide a display device and a method of driving it, capable of displaying images properly even upon asynchronous input of image data while taking advantages of decreased power consumption implemented by intermission driving. When there is an external input of new image data (image F) in a non-refreshing period in an intermission driving display device which performs intermittent refreshing based on the latest image data that is inputted in and read out from a frame memory, a coercive refreshing is started immediately based on the new image data (image F) (see the sixth frame period). Also, when there is an external input of image data (image G) during a refreshing period for the image F, the ongoing frame period including the refreshing of the image F is completed and immediately thereafter, a coercive refreshing based on the image data (image G) is started (see the ninth frame period).

Display device and method of driving the same

Provided is a display device capable of displaying a smooth video even when pause drive is performed. In a liquid crystal display device with an animation function, 12-Hz pause drive is performed with vertical display periods, each having a duration of five frames. In a video display period, an animation video changes every duration of a secondary video display period, i.e., every one frame, in the order: images A to X, then A and B. Once the video display period starts, 12-Hz pause drive switches to 60-Hz normal drive. In this case, for the animation video that changes every duration of the secondary video display period, i.e., every one frame, in the order: images A to X, then A and B, refresh is performed every duration of the vertical display period, i.e., every one frame. In this manner, the duration of the vertical display period is set to be the same as the duration of the secondary video display period, whereby refresh is performed individually for images A to X, A, and B included in the animation video.

Display device, electronic device comprising same, and drive method for display device

The purpose of the present invention is to provide a display device in which the occurrence of crosstalk can be suppressed. A display device () includes a display unit and a separation unit (). The display unit displays a synthetic image formed by dividing each of a plurality of images that are different from one another and arraying the divisional images thus obtained in a predetermined order. The separation unit () separates the plurality of images contained in the synthetic image. The display unit includes a storage unit () and a correction unit (). The storage unit () stores crosstalk levels set with respect to respective combinations of gray scale level data including gray scale level data of a pixel displaying an image that a viewer is supposed to see, among the plurality of images contained in the synthetic image, and gray scale level data of a pixel serving as a factor that causes crosstalk. The correction unit () corrects the gray scale level data of the pixel displaying the image that a viewer is supposed to see, by using the crosstalk levels read out of the storage unit ().

Display device with crosstalk level correction

Provided is a display device capable of suppressing reduction in display quality even when pause drive is performed, while allowing the intensity of a light source to be changed in accordance with images to be displayed. In a liquid crystal display device with the CABC function, 7.5-Hz pause drive is performed. A transition period is provided in which images to be displayed are changed gradually from bright image X to dark image Y. In the transition period, the duration of a sub-transition period is five frames. Once the transition period starts, the duration of a vertical display period changes from eight frames to one frame. That is, 7.5-Hz pause drive switches to 60-Hz normal drive. In this manner, the duration of the vertical display period is set to be less than or equal to the duration of the sub-transition period, so that screen refresh is always performed in each sub-transition period of the transition period.

A liquid crystal display deviceaccording to the present invention includes a processing deviceconfigured to process an image signal D to be input into a pixel P of a liquid crystal panelconfigured to provide a display based on light applied from LEDsarranged in a peripheral area R. The process deviceincludes a receiving section, a correction section, and a calculation section, for example. The calculation section is configured to calculate luminance components to be provided by the respective LEDsto the pixel P based on a distance between each LEDand the pixel P, add a total luminance that is a sum of the luminance components to be provided by the LEDsto a predetermined expected luminance to calculate an added luminance, and calculate a correction coefficient HP with respect to the pixel P based on a luminance ratio between the added luminance and the reference luminance.

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Osaka, Japan

Kouji Kumada