Sharp Kabushiki Kaisha Corporation

Akizumi Fujioka

Toshihiro Yanagi

Taketoshi Nakano

Kazuki Takahashi

Asahi Yamato

Kohji Saitoh

Masami Ozaki

Ken Inada

Jun Nakata

Kohzoh Takahashi

Akinori Kubota

Yoshinori Shibata

Noriyuki Tanaka

Kouji Kumada

Keiichi Yamamoto

Fumiyuki Kobayashi

Satoshi Ihida

Naru Usukura

Kazuo Nakamura

Masaki Uehata

Mikihiro Noma

Toshimitsu Gotoh

Atsushi Sakamoto

Tadashi Nemoto

Yuta Tanaka

Kohji Ogata

Maremu Yamagishi

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

The occurrence of flicker is effectively suppressed particularly in a liquid crystal display device that performs low-frequency driving. Provided are a gradation-to-voltage value conversion table for converting a gradation to a voltage value, a correction value map for storing a correction value, and a voltage value-to-gradation conversion table for converting a voltage value to a gradation. A gradation of an input image signal is converted to a first voltage value, using the gradation-to-voltage value conversion table. The correction value specified in accordance with a location of a pixel to be processed is added to or subtracted from the first voltage value so that a second voltage value is obtained. The second voltage value is converted to an output gradation, using the voltage value-to-gradation conversion table. A driving video signal is applied to a source bus line, based on the output gradation.

Liquid crystal display device and method for driving same

A liquid crystal display device is provided where deterioration of the liquid crystal panel is prevented while reducing power consumption. A liquid crystal panel () includes a display region () in which a video is displayed. The display region () includes a plurality of sub-regions (A,B,C,D). A drive unit () rewrites the display on at least one of the plurality of sub-regions (A,B,C,D) based on a video signal. An identification unit () identifies the one of the plurality of sub-regions (A,B,C,D) on which the drive unit () has not rewritten the display for a predetermined number of frames. An output unit () outputs an interrupt signal for requesting a video signal for rewriting the display on the sub-region identified by the identification unit.

Liquid crystal display device

A liquid crystal display device that performs intermittent driving involving a driving period and an idle period includes a gray scale level control unit that generates, from an input image signal, an image signal for display and an image signal for correction. A signal line control unit writes the image signal for correction to the plurality of signal lines before writing the image signal for display during a driving period. An LUT stores a correction gray scale value associated with a gray scale value of at least a current frame. An adding circuit corrects the input image signal based on the correction gray scale value read from the LUT. The subtracting circuit specifies, in a pixel region, a regular image pattern including at least a first pixel and a second pixel and changes an output from the adding circuit for the first image by a predetermined gray scale width.

Liquid crystal display device and method of driving the same

A liquid crystal display device () includes: a liquid crystal display panel (); a scan line driving circuit () that supplies a scan signal voltage to each pixel (Px) via a corresponding scan line (); a signal line driving circuit () that supplies a display signal voltage to each pixel via a corresponding signal line (); and a display control section () including a polarity reversal driving switching section () that switches a mode of polarity reversal of the display signal voltage. In a case where the polarity reversal driving switching section switches the polarity reversal mode in transition from a first vertical scan period to a second vertical scan period immediately succeeding the first vertical scan period, the display control section is capable of making a largeness of a display signal voltage supplied in the second vertical scan period different from its original largeness only for a pixel group included in the plurality of pixels to which display signal voltages that have the same polarity in both the first and second vertical scan periods are supplied.

The present invention provides a liquid crystal display device capable of suppressing a decrease in display quality when pause drive is performed in an alternating-voltage drive mode, as well as a method for driving the same. In a first drive frame, overshoot drive is performed using correction values provided by an LUT to apply overshoot voltages whose absolute values are higher than absolute values of signal voltages to data signal lines. Subsequently, in a second drive frame, normal drive is performed to write signal voltages of the same polarity as the overshoot drive voltages to the data signal lines. Thereafter, a pause period in which an image written by normal drive is displayed continues until the start of a drive period in the next pause drive period. As a result, a decrease in luminance immediately after the signal voltages are written during the second drive frame is suppressed significantly, so that the viewer barely recognizes flicker.

Grayscale values for previous and current frames are different, and therefore, an overshoot voltage, which has a higher absolute value than a signal voltage, are applied to a data signal line. Next, in a second drive frame, normal drive is performed, so that a signal voltage of the same polarity as the overshoot voltage is written to the data signal line. Moreover, in a first drive frame of a third pause drive period, the grayscale values for the previous and current frames are equal, and also greater than or equal to a boundary value, and therefore, undershoot drive is performed. An undershoot voltage, which has a lower absolute value than a signal voltage, is applied to the data signal line. Next, in a second drive frame, normal drive is performed, so that a signal voltage of the same polarity as the undershoot voltage is written to the data signal line.

A processor determines a drive scheme from among candidates of a plurality of drive schemes having differing schemes for supplying a signal to a signal line of a display panel. A controller stores a scheme drive information in which a drive scheme information and a signal control information in a drive scheme are associated. A controller receives a scheme information from a processor, and controls a signal supplied to a signal line of a display panel, the control being made based on a scheme information and a scheme drive information.

Display control system, processor, controller, and display control method

According to a liquid crystal display device (), a gate driver is controlled to (a) scan all of scan signal lines during at least two driving frames contained in a first driving period and (b) not scan any of the scan signal lines during pausing frames in a pausing period which is (i) secured between the first driving period and a second driving period by which the first driving period is followed and (ii) is longer than each of the first and second driving periods.

Liquid crystal display device with drive control circuit and method for driving same

An image determination part configured to determine whether or not an image based on an input image signal is an image analogous to a polarity reversal pattern in a reversal driving scheme employed by default and to output a determination result, and a reversal pattern decision part configured to decide a reversal driving scheme based on the determination result are provided as constituent elements anterior to a liquid crystal drive unit. With regard to each unit area where the determination by the image determination part is made, the reversal pattern decision part decides the reversal driving scheme in the unit area, as a reversal driving scheme different from the reversal driving scheme employed by default, when the determination result indicates that the image based on the input image signal is the image analogous to the polarity reversal pattern in the reversal driving scheme employed by default.

Included are: refresh a rate changing section () for changing a refresh rate of a display panel () by configuring settings for scan periods during each of which a plurality of gate signal lines (G) of the display panel () are sequentially scanned and for pause periods during each of which sequential scanning of the plurality of gate signal lines (G) is suspended; and a drive amount control section () for controlling, in accordance with a ratio of the scan periods to the pause periods, drive time during which each of the gate signal lines is driven in each of the scan periods.

Drive device and display device

In a case where a display device () receives an instruction to change a refresh rate of a display panel (), the display device () changes the refresh rate with a timing with which there is a balance between the length of time for which positive source signals are written and the length of time for which negative source signals are written.

Drive device changing refresh rate of display panel and display device including drive device

A timing controller carries out display refresh on a display panel in a first frame which comes one frame after a second frame in which (i) an image signal supplied from an interface matches an image signal stored in a frame memory and (ii) a polarity balance value is equal to a reference value. In this case, the image signal, having a polarity opposite to that of pixel applied voltages in the second frame, is supplied to the display panel in the first frame. This makes it possible to prevent a deterioration in the display panel while reducing electric power consumption.

Display device driving method, display device, and liquid crystal display device

A display device () in accordance with the present invention includes a detection section () provided along a display panel () and detecting an approach or a contact of an object. The detection section () detects the approach or the contact of the object in a period which (i) is from a time point when supply of a scanning signal to a gate signal line (G) is started to a time point when supply of the scanning signal to a subsequent gate signal line (G) is started but (ii) excludes a rising period of a source signal supplied to a source signal line (S).

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Osaka, Japan

Akizumi Fujioka