Waveform Generation Patents (Class 345/94)
-
Publication number: 20130057461Abstract: A tangent angle circuit is connected to a plurality of scan line driving circuits and comprises: a charging module integrated on a control board to receive input of a direct current (DC) driving voltage and output a cut-in voltage to charge the scan line driving circuits; and a plurality of discharging modules integrated on the scan line driving circuits respectively to control the corresponding scan line driving circuits to discharge. In the present invention, by distributing the discharging modules on each of the scan line driving circuits respectively, the burden of load discharged charges on the discharging modules is reduced to avoid occurrence of an overhigh temperature; and the discharging modules are spatially separated, which is further favorable for reducing the temperature, releasing the space of the control board and reducing the area of the control board.Type: ApplicationFiled: September 19, 2011Publication date: March 7, 2013Applicant: SHENZHEN CHINA STAR OPTOELECTRONICS TECHNOLOGY CO., LTD.Inventors: Po-shen Lin, Xiaoping Tan, Jianyong Fu
-
Patent number: 8384633Abstract: An optical writing display apparatus that performs: applying to a pair of electrodes a first voltage having a first polarity that applies a first partial voltage to a cholesteric liquid crystal layer, the first partial voltage being more than a threshold at which the state of the cholesteric liquid crystal layer changes from focal conic to homeotropic when the exposure is conducted, and exposing an photoconductive layer to light; stopping applying the first voltage for a predetermined time and exposing the photoconductive layer to light; applying a second voltage having a second polarity opposite to the first polarity that applies a second partial voltage to the cholesteric liquid crystal layer, the second partial voltage being not more than the above threshold when the exposure is not conducted, but more than the above threshold when the exposure is conducted; and selectively exposing the photoconductive layer to light and stopping applying the second voltage.Type: GrantFiled: April 29, 2009Date of Patent: February 26, 2013Assignee: Fuji Xerox Co., Ltd.Inventors: Yasuhiro Yamaguchi, Tomozumi Uesaka
-
Patent number: 8384628Abstract: A document including an integrated display device that has several triggerable display elements, each of which is designed to emit an optical signal for representing first data stored in the document whereby the display device is designed for cyclical activation of the display elements for rendering the first data in sequential image regeneration periods, and whereby the display device is designed in such a way that the emission of the optical signals of at least a subset of the display element takes place with a chronological delay, whereby it is not possible to visually perceive the chronological delay.Type: GrantFiled: November 4, 2008Date of Patent: February 26, 2013Assignee: Bundesdruckerei GmbHInventors: Arthur Mathea, Jörg Fischer, Manfred Paeschke, Malte Pflughoefft, Oliver Muth
-
Patent number: 8384645Abstract: A method for driving an LCD panel and an LCD using the same are provided. The method includes following steps. Firstly, a number of scan signals are provided sequentially, and an enabling time of the scan signals excluding the last scan signal is adjusted according to a compensation time, so as to unfix the enabling time of these scan signals. Next, the scan signals having the unfixed enabling time are sequentially provided to an LCD panel, so as to turn on a number of row pixels of the LCD panel one by one. Thereby, the entire brightness of the LCD can be uniformed by applying the method disclosed in the present invention.Type: GrantFiled: May 29, 2008Date of Patent: February 26, 2013Assignee: Au Optronics CorporationInventors: Mei-Sheng Ma, Chien-Hung Chen, Chun-Huai Li
-
Patent number: 8368629Abstract: This document relates to a liquid crystal display capable of improving picture quality by compensating for difference in charge between liquid crystal cells. The liquid crystal display comprises a liquid crystal display panel; a gate driving circuit; a charge difference compensation circuit configured to generate, in a specific gray level range, analog positive gamma voltages having a first reference level and analog negative gamma voltages having a second reference level in synchronization with a first scan time at which a first gate line is driven, and generate the analog positive gamma voltages having a first compensation level that is lower than the first reference level and the analog negative gamma voltages having a second compensation level that is higher than the second reference level in synchronization with a second scan time at which a second gate line is driven; and a data driving circuit.Type: GrantFiled: July 21, 2009Date of Patent: February 5, 2013Assignee: LG Display Co., Ltd.Inventors: Yongchae Jung, Seungchul Park, Sangjin Nam
-
Publication number: 20130027287Abstract: A display apparatus includes a gate driver which sequentially outputs a gate signal at a high state in response to a gate control signal and a data driver which converts image data into a data signal in response to a data control signal. The display apparatus further includes a display panel which includes a plurality of gate lines which sequentially receive the gate signal, a plurality of data lines which receive the data signal and a plurality of pixels connected to the gate and data lines and which receive the data signal in response to the gate signal to display an image. The polarity of the data signal is inverted after the gate signal transitions to a low state.Type: ApplicationFiled: October 4, 2012Publication date: January 31, 2013Inventors: Min-Cheol LEE, Byeong-Jae AHN, Jong-Hwan LEE, Yeon-Kyu MOON, Jong-Hyuk LEE
-
Patent number: 8358260Abstract: A display device may include a flat panel display, and a controller coupled to the flat panel display. The controller may be configured to determine an operating mode for the flat panel display among a plurality of operating modes including at least a first operating mode and a second operating mode. In the first operating mode, the controller may set the flat panel display to utilize a first frame rate and a first inversion mode to save power. In the second operating mode, the controller may set the flat panel display to utilize a second frame rate, a second inversion mode, and a black frame insertion to improve image quality. The second frame rate may be faster than the first frame rate. The second inversion mode and black frame insertion may be mutually configured to maintain a DC balanced operation of the flat panel display.Type: GrantFiled: April 6, 2009Date of Patent: January 22, 2013Assignee: Intel CorporationInventors: Akihiro Takagi, Cheng-Shih Chin, Yanli Zhang, Maximino Vasquez
-
Patent number: 8344983Abstract: A liquid crystal display apparatus includes a plurality of areas in which response speeds greatly different from each other coexist in a pixel. A first replacement process section replaces the image data of the desired target frame with a first gradation, when a gradation transition from a current frame to a desired target frame corresponds to the above gradation transition. A second replacement process section replaces the image data of the current frame with a second value. The first value is set to a value causing the pixel to respond at a relatively higher speed without the occurrence of the excessive brightness. Without avoiding the deterioration of the image, it is possible to drive a liquid crystal display apparatus including areas whose response speeds are different from each other coexist in the pixel, such as a liquid crystal display apparatus of vertically aligned mode and normally black mode.Type: GrantFiled: February 1, 2012Date of Patent: January 1, 2013Assignee: Sharp Kabushiki KaishaInventors: Makoto Shiomi, Kazunari Tomizawa, Koichi Miyachi, Tomoo Furukawa
-
Patent number: 8344996Abstract: A method for updating a submatrix of a display matrix of a display device comprises sequentially selecting rows of the display matrix starting from an initial row of the display matrix. The method includes determining whether a selected row precedes a first row of the submatrix in a first drive frame of a waveform having two or more drive frames. If a condition that a selected row precedes the first row of the submatrix in the first drive frame of the waveform is false, the method includes addressing the selected row for a first line address period. If a condition that a selected row precedes the first row of the submatrix in the first drive frame of the waveform is true, the method includes addressing the selected row for a second line address period.Type: GrantFiled: July 27, 2009Date of Patent: January 1, 2013Assignee: Seiko Epson CorporationInventors: Jimmy Kwok Lap Lai, Eric Jeffrey
-
Patent number: 8344977Abstract: A liquid crystal display comprising: a receiver for receiving power and differential signal; a backlight power supply which supplies the power to a backlight unit; a power-off sensor which senses power-off of the backlight power supply and distorts one of the differential signals; and a controller which senses the distortion of the differential signal and generates an after-image removing gray-scale signal.Type: GrantFiled: May 22, 2008Date of Patent: January 1, 2013Assignee: Samsung Display Co., Ltd.Inventors: Ju-Young Park, Kyung-Hun Lee
-
Patent number: 8339347Abstract: A liquid crystal display includes; a liquid crystal panel, and a DC-DC converter which receives an input voltage to generate an analog drive voltage and a gate-on voltage used to operate the liquid crystal panel, wherein the DC-DC converter includes a pulse width modulation circuit which modulates a pulse width of the analog drive voltage and the gate-on voltage, a boost converter which boosts the input voltage to output the analog drive voltage, and a charge pump which boosts one of the input voltage and the analog drive voltage to output the gate-on voltage, wherein when a high voltage stress test is performed, the DC-DC converter outputs the analog drive voltage boosted to a voltage level higher than a voltage level of the analog drive voltage during a normal operation, and outputs the gate-on voltage having a voltage level substantially equal to a voltage level of the gate-on voltage during the normal operation.Type: GrantFiled: March 24, 2009Date of Patent: December 25, 2012Assignee: Samsung Display Co., Ltd.Inventors: Hyeon-Seok Bae, Sang-Chul Lee, Kwang-Youl Lee
-
Patent number: 8339390Abstract: Provided are a power supply circuit and a display device which are capable of enhancing power efficiency even when applied to a display panel whose current consumption varies. The power supply circuit boosts and outputs an input voltage using a booster chopper circuit. A frequency control circuit changes a frequency of a clock signal, which controls a switch of the chopper circuit, in accordance with a load of the power supply circuit. The frequency control circuit divides an operation of the display device into a display effective period at a high load and a vertical retrace period at a low load, based on a vertical synchronizing signal and a horizontal synchronizing signal. The frequency control circuit sets the frequency of the clock signal in a high-load period to be higher than that in a low-load period.Type: GrantFiled: November 25, 2009Date of Patent: December 25, 2012Assignees: Hitachi Displays, Ltd., Panasonic Liquid Crystal Display Co., Ltd.Inventors: Naoki Takada, Naruhiko Kasai, Takuya Eriguchi, Yuki Okada, Mitsuru Goto, Yoshihiro Kotani
-
Patent number: 8339425Abstract: A pixel is driven by first converted image data having a first polarity and being converted by an A-gamma curve during an (N)th frame where ‘N’ is a natural number. The pixel is driven by second converted image data having a second polarity opposite to the first polarity and being converted using the A-gamma curve during an (N+1)th frame. The pixel is driven by third converted image data having the first polarity and being converted using a B-gamma curve different from the A-gamma curve during an (N+2)th frame. The pixel is driven by fourth converted image data having the second polarity and being converted by the B-gamma curve during an (N+3)th frame.Type: GrantFiled: March 30, 2009Date of Patent: December 25, 2012Assignee: Samsung Display Co., Ltd.Inventors: Byung-Hyuk Shin, Hyoung-Sik Nam
-
Publication number: 20120319935Abstract: An objective of the present invention is to provide a display device which operates with low power consumption and is highly flexible with respect to design of image display. Provided on a substrate which constitutes a liquid crystal panel are a normal display portion, in which image display is performed by typical active-matrix drive, and a memory display portion, in which image display is performed by memory drive. Each pixel in the memory display portion is shaped so as to include a curve or a side not parallel to either gate bus lines (GL) or source bus lines (SL). A plurality of pixel memory units (PMU), each including a flip-flop, are provided so as to correspond to their respective pixels in the memory display portion. Display data (DATA) is provided to the pixel memory unit (PMU(1)) that corresponds to the first stage of a shift register which is constituted by connecting the flip-flops in the plurality of pixel memory units (PMU) in series.Type: ApplicationFiled: April 7, 2011Publication date: December 20, 2012Applicant: SHARP KABUSHIKI KAISHAInventor: Hajime Washio
-
Publication number: 20120320018Abstract: A liquid crystal display device (1) in accordance with the present invention includes a first common electrode (11) and a second common electrode (12) in each pixel region of a display panel. The device (1) further includes delay circuit (A and B) for delaying the timings of polarity reversals of a first common electrode signal and a second common electrode signal which are respectively input to the first common electrode (11) and the second common electrode (12), said delaying being performed when the first common electrode signal and the second common electrode signal are subjected to respective polarity reversals in each horizontal scan period. The present invention thus provides a liquid crystal display device which, in a display device with wide viewing angle characteristics, lowers peak inrush current which is generated when the common electrode signal (common electrode voltage) is subjected to a polarity reversal.Type: ApplicationFiled: November 8, 2010Publication date: December 20, 2012Applicant: Sharp Kabushiki KaishaInventors: Kohji Saitoh, Masami Ozaki
-
Publication number: 20120320016Abstract: Disclosed is a liquid crystal display device (10) including a matrix of pixels P. Each pixel P includes: a pixel electrode (30) to which a data potential supplied via a source wire (12) is applied; a retention capacitor (33) for storing the data potential temporarily before the data potential is applied to the pixel electrode (30); a transistor (31), connected to a gate wire (11a) for scanning and the source wire (12), for applying the data potential supplied via the source wire (12) to the retention capacitor (33); a transistor (34) for use in collective charging, provided between the retention capacitor (33) and the pixel electrode (30), for applying to the pixel electrode (30) the data potential temporarily applied across the retention capacitor (33); and a transistor (35) for use in collective discharging, connected to the pixel electrode (30), for discharging the pixel electrode.Type: ApplicationFiled: November 30, 2010Publication date: December 20, 2012Inventor: Mitsuaki Hirata
-
Patent number: 8334830Abstract: Disclosed is a liquid crystal driving device, which is without a gate PCB, having improved uniformity of screen, and a driving method thereof. The liquid crystal driving device comprises: a sequence recognition means for recognizing sequence of a pertinent gate driver IC by a pulse width of a vertical start signal inputted in synchronization with a vertical synchronous signal, and generating a Carry signal and location data of the pertinent gate driver IC; and gate-off voltage generation means for receiving a first gate-off voltage and the location data of the pertinent gate driver IC, and outputting a second gate-off voltage which is generated by subtracting a voltage attenuation quantity corresponding to the location data of the gate driver IC from the first gate-off voltage.Type: GrantFiled: July 11, 2011Date of Patent: December 18, 2012Assignee: SK Hynix Inc.Inventors: Dong Hwan Lee, Tae Hyuk Kwon
-
Patent number: 8330693Abstract: A two-stage drive waveform switches a DFLC from a high tilt state to a low tilt state quickly and without scattering. A relaxation voltage is applied to delay the onset of the high amplitude high frequency kick voltage when switching from a high tilt state to a low tilt state. The relaxation voltage allows the molecules to ‘relax’ in accordance with their own elasticity towards their low tilt state in the direction of the average azimuth angle of the low tilt state. The kick voltage is then applied to drive the molecules quickly to the low tilt state. Optimal switching time and the desired molecular response is achieved by delaying the onset of the large kick voltage via application of the relaxation voltage. The relaxation voltage may constitute a lower amplitude holding voltage, a small or zero DC voltage or a smooth windowing of the kick voltage.Type: GrantFiled: July 2, 2009Date of Patent: December 11, 2012Assignee: Teledyne Scientific & Imaging, LLCInventors: Bing Wen, Dong-Feng Gu
-
Patent number: 8330694Abstract: The liquid crystal display apparatus includes a liquid crystal modulation element including first and second electrode, a liquid crystal layer disposed between the first and second electrodes, a first alignment film disposed between the first electrode and the liquid crystal layer, and a second alignment film disposed between the second electrode and the liquid crystal layer. The apparatus further includes a controller that respectively provides first and second electric potentials to the first and second electrodes such that a sign of an electric field generated in the liquid crystal layer is cyclically inverted in a modulation operation state. The controller respectively provides third and fourth electric potentials to the first and second electrodes such that the sign of the electric field is fixed in a state other than the modulation operation state. The apparatus can avoid an influence by cumulated charged particles without adding a new member.Type: GrantFiled: June 4, 2008Date of Patent: December 11, 2012Assignee: Canon Kabushiki KaishaInventor: Masayuki Abe
-
Patent number: 8325125Abstract: A display apparatus includes a cholesteric liquid crystal display panel, a control circuit and a driving circuit. The control circuit classifies pixels into different gradation level groups. The driving circuit applies a first driving waveform to the cholesteric liquid crystal display panel to bring pixels belonging to the first and the fourth group into a state corresponding to the highest gradation level, pixels belonging to the second group into a state corresponding to the lowest gradation level, and pixels belonging to the third group into states corresponding to gradation levels to be displayed, and applies a second driving waveform to the cholesteric liquid crystal display panel to bring pixels belonging to the fourth group into states corresponding to gradation levels to be displayed.Type: GrantFiled: March 1, 2010Date of Patent: December 4, 2012Assignee: Fujitsu LimitedInventors: Tomohisa Shingai, Masaki Nose, Hirokata Uehara
-
Patent number: 8319764Abstract: Electronic displays encounter visibility issues due to varying ambient light conditions. An ambient light sensor can be provided to sense ambient light and dynamically adjust display brightness to compensate for changes in ambient light. A wave guide for improving angular response in a light sensor is provided.Type: GrantFiled: June 29, 2009Date of Patent: November 27, 2012Assignee: Research In Motion LimitedInventors: Hsin Chin Lee, Matthew Broga
-
Patent number: 8319766Abstract: Electronic Paper Displays can suffer from “ghosting” or previous images remaining partially visible after the display has updated to show a new image. A pseudo-random noise intermediate image is used to make the ghosting less visible to human observers. Further, other intermediate images can be used to convey visible information or to convey secret information, e.g. a watermark. A control signal for driving the bi-stable display from the current optical state to an intermediate state, then to a final optical state is also determined. In some embodiments, the intermediate state for each pixel is determined in a pseudo-random manner. The pseudo-random noise values are applied to the bi-stable display to remove noise and other artifacts from the end resulting images. The determined control signal is applied to the bi-stable display to drive the bi-stable to the intermediate state, then to the final optical state.Type: GrantFiled: March 31, 2008Date of Patent: November 27, 2012Assignee: Ricoh Co., Ltd.Inventors: Michael J. Gormish, Guotong Feng
-
Patent number: 8319768Abstract: A data line driving circuit for a liquid crystal display device comprising: a plurality of first data lines applied with a positive potential, a plurality of second data lines applied with a negative potential, comparison units that compare with a reference voltage at least one of a potential at a first common line connected to the plurality of first data lines and a potential at a second common line connected to the plurality of second data lines, and switches that are controlled so that the first data lines and the second data lines are set to a connection state or an interruption state according to a comparison result by the comparison units.Type: GrantFiled: September 14, 2009Date of Patent: November 27, 2012Assignee: RENESAS Electronics CorporationInventor: Junya Yokota
-
Publication number: 20120293560Abstract: A liquid crystal display having common voltage compensation mechanism includes a liquid-crystal capacitor common electrode for receiving a liquid-crystal capacitor common voltage, a storage capacitor common electrode for receiving a storage capacitor common voltage, a common voltage generator for providing the liquid-crystal capacitor common voltage according to a preliminary common voltage, a common voltage compensation circuit electrically connected to the liquid-crystal capacitor common electrode and the storage capacitor common electrode, and a timing controller electrically connected to the common voltage compensation circuit. The common voltage compensation circuit is utilized for generating the storage capacitor common voltage through performing a ripple inverting operation according to the liquid-crystal capacitor common voltage, the preliminary common voltage and a compensation control signal.Type: ApplicationFiled: November 21, 2011Publication date: November 22, 2012Inventors: Ching-Lin Li, Yi-Fan Lin, Jen-Chieh Chen
-
Patent number: 8310475Abstract: For the purpose of providing a display apparatus capable of improving display quality by expanding the light-emission area of pixels by improving the layout of pixels and common power-feed lines formed on a substrate, pixels (7A, 7B) including a light-emission element (40), such as an electroluminescence element or an LED element, are arranged on both sides of common power-feed lines (com) so that the number of common power-feed lines (com) is reduced. Further, the polarity of a driving current flowing between the pixels (7A, 7B) and the light-emission element (40) is inverted so that the amount of current flowing through the common power-supply lines “com” is reduced.Type: GrantFiled: March 5, 2008Date of Patent: November 13, 2012Assignee: Seiko Epson CorporationInventor: Tokuroh Ozawa
-
Patent number: 8305319Abstract: A liquid crystal display (LCD) device includes an LCD panel, and a common voltage generating circuit configured for providing common voltages to the LCD panel. The common voltage generating circuit includes a microprocessor, a timer, a voltage adjustment circuit, and a look up table. The microprocessor is electrically connected to the timer, the look up table, and the voltage adjustment circuit. The timer is configured for recording a continuous operated time of the LCD panel. The look up table is configured for storing optimal common voltages corresponding to each continuous operated time. The microprocessor is configured for reading the optimal common voltage at set intervals corresponding to the continuous operated time, and controlling the voltage adjustment circuit to provide the corresponding optimal common voltage to the LCD panel.Type: GrantFiled: March 30, 2009Date of Patent: November 6, 2012Assignee: Chimei InnoLux CorporationInventors: Chih-Sheng Chang, Chao-Yi Hung, Sz-Hsiao Chen, Sheng-Tien Cho, Chueh-Ju Chen, Tsau-Hua Hsieh, Chiu-Lien Yang
-
Patent number: 8305318Abstract: A liquid crystal display device includes pixels, gate lines and source lines, active elements, a gate driver circuit, a source driver circuit, and a timing controller circuit. The source driver circuit conducts a prescribed operation of supplying the source signals of positive polarity and negative polarity having a prescribed voltage to the source lines during a vertical blanking interval, and electrically cutting the source lines off after the supply of the source signals while establishing a short circuit between adjoining source lines supplied with the source signals of opposite polarities, thereby causing the source lines to hold a prescribed DC voltage value.Type: GrantFiled: June 7, 2007Date of Patent: November 6, 2012Assignee: Mitsubishi Electric CorporationInventor: Kazuhiro Ishiguchi
-
Patent number: 8305323Abstract: A display apparatus includes a gate driver which sequentially outputs a gate signal at a high state in response to a gate control signal and a data driver which converts image data into a data signal in response to a data control signal. The display apparatus further includes a display panel which includes a plurality of gate lines which sequentially receive the gate signal, a plurality of data lines which receive the data signal and a plurality of pixels connected to the gate and data lines and which receive the data signal in response to the gate signal to display an image. The polarity of the data signal is inverted after the gate signal transitions to a low state.Type: GrantFiled: December 19, 2007Date of Patent: November 6, 2012Assignee: Samsung Electronics Co., Ltd.Inventors: Min-Cheol Lee, Byeong-Jae Ahn, Jong-Hwan Lee, Yeon-Kyu Moon, Jong-Hyuk Lee
-
Patent number: 8305320Abstract: A liquid crystal display and a driving method thereof are provided. The liquid crystal includes a liquid crystal display panel, a data driving circuit, a gate driving circuit, a timing controller, and an over-driving controller. The over-driving controller, if a difference between input data input during a (N)th frame period (N is a positive integer) and (N?1)th frame data read from a memory is more than 2 gray levels, modulates the data at an over/under shoot ratio of 20 to 80% and supplies the modulated data to the timing controller, if the difference is less than 2 gray levels, differently supplies the input data to the timing controller and converts the least significant bit of the data stored in the memory according to whether or not the data is modulated.Type: GrantFiled: August 25, 2009Date of Patent: November 6, 2012Assignee: LG Display Co., Ltd.Inventors: Gihong Kim, Jaekyeong Yun
-
Patent number: 8300037Abstract: A liquid crystal display device includes a plurality of data signal lines and scanning signal lines intersecting orthogonally with the data signal lines; pixel electrodes each provided at each of intersections of the plurality of data signal lines and scanning signal lines; and a counter electrode, the plurality of data signal lines are divided into sets each including data signal lines that are provided next to one another so as to respectively correspond to primary colors constituting a display color, the data signal lines in each set being connected to one of output signal lines to which data signals corresponding to the primary colors are supplied during a single horizontal scanning period by time division, the data signals supplied to the output signal lines being switched, the counter electrode being subjected to application of a voltage being varied during at least one horizontal scanning period.Type: GrantFiled: April 24, 2008Date of Patent: October 30, 2012Assignee: Sharp Kabushiki KaishaInventor: Tatsuhiko Suyama
-
Patent number: 8300006Abstract: Electrophoretic display units (1) comprising pixels (11) situated between common electrodes (6) and pixel electrodes (5) need, for shortening the total image update times, increased driving voltages across the pixels (11) which endanger transistors (12) coupled to the pixel electrodes (5). These increased driving voltage (V6) to the common electrode (6). To protect the transistors (12) against these increased driving voltages, a setting signal (S1, S2) is supplied to the pixel electrode (5) via the transistor (12) for reducing a voltage across the pixel (11) resulting from a transition in the alternating voltage signal (V6). During driving frame periods (Fd) data pulses (D1, D2, D3, D4, D5, D6) are supplied, and during setting frame periods (Fs), the setting signals (S1, S2) are supplied.Type: GrantFiled: September 27, 2004Date of Patent: October 30, 2012Assignee: E Ink CorporationInventors: Guofu Zhou, Masaru Yasui, Mark Thomas Johnson, Robert Waverly Zehner, Karl Raymond Amundson
-
Patent number: 8294645Abstract: The invention provides a liquid crystal device and method thereof. Subsequent to applying a first electrical voltage on a liquid crystal to induce a reorientation of the liquid crystal, a second electrical voltage with proper polarity is applied on the liquid crystal to assist the relaxation of the reorientation that was induced by the first electrical voltage. The “switch-off” phase of the liquid crystal can therefore be accelerated or temporally shortened, and the device can exhibit better performance such as fast response to on/off signals. The invention can be widely used LCD, LC shutter, LC lens, spatial light modulator, telecommunication device, tunable filter, beam steering device, and electrically driven LC device, among others.Type: GrantFiled: March 12, 2009Date of Patent: October 23, 2012Assignee: Kent State UniversityInventors: Sergij V. Shiyanovskii, Mingxia Gu, Oleg D. Lavrentovich
-
Patent number: 8294652Abstract: A driving method for driving an LCD panel having a counter electrode and a source line. In a first period, the counter electrode is driven to a potential VCOMH. In a second period, the counter electrode and the source line are short-circuited to a power supply interconnection having a power supply potential VCI. In a third period, the counter electrode is connected to a ground interconnection while the source line is kept to be short-circuited to the power supply interconnection. In a fourth period, the counter electrode is pulled down to a potential VCOML lower than a ground potential In a fifth period, the source line is driven to a potential corresponding to an image data while the counter electrode is kept to the potential VCOML. The electric power consumed in pulling down the counter electrode from a positive potential to a negative potential can be effectively reduced.Type: GrantFiled: October 30, 2008Date of Patent: October 23, 2012Assignee: Renesas Electronics CorporationInventor: Hiroaki Shirai
-
Publication number: 20120262497Abstract: A scan-line driving device for a LCD apparatus is provided. The scan-line driving device comprises a PWM signal generating circuit, two impedances with different resistance values, a capacitor and two scan drivers. The PWM signal generating circuit outputs a PWM signal with two potentials and a predetermined duty cycle. A terminal of the capacitor is electrically coupled to a ground potential, and the other terminal of the capacitor receives the PWM signal. Each of the scan drivers comprises a core circuit and a transistor. A source/drain terminal of each transistor is electrically coupled to a PWM signal input terminal of a corresponding core circuit and the other terminal of the capacitor, the other source/drain terminal of each transistor is electrically coupled to the ground potential through a corresponding one of the impedances, and the gate terminal of each transistor receives a turn-on control signal.Type: ApplicationFiled: September 29, 2011Publication date: October 18, 2012Applicant: AU OPTRONICS CORP.Inventor: Meng-Sheng CHANG
-
Patent number: 8289312Abstract: In a liquid crystal display device performing alternating-current driving, at least one of a gate voltage amplitude Vgp?p(p) upon application of a positive polarity voltage and a gate voltage amplitude Vgp?p(n) upon application of a negative polarity voltage is changed in accordance with a liquid crystal driving frequency. Thus, an effective value of a liquid crystal application voltage in a positive polarity is set to be equal to an effective value of a liquid crystal application voltage in a negative polarity irrespective of the liquid crystal driving frequency, so that flicker is prevented from occurring when the liquid crystal driving frequency is switched. As the liquid crystal driving frequency is low, a gate low voltage Vgln after application of the negative polarity voltage is set to be low. Thus, a leak current from a TFT is reduced in the negative polarity, and a liquid crystal element is improved in voltage holding ratio.Type: GrantFiled: December 7, 2007Date of Patent: October 16, 2012Assignee: Sharp Kabushiki KaishaInventors: Noriko Matsuda, Atsuhito Murai, Masaki Uehata, Takashi Kurihara
-
Patent number: 8289256Abstract: A liquid crystal display (LCD) includes: a gate-off voltage generator including a temperature compensation unit which includes a constant voltage output device and a temperature-sensing device and outputting a gate-off voltage whose level varies according to a change in ambient temperature; a clock generator receiving a gate-on voltage and the gate-off voltage and outputting a first clock signal and a second clock signal; a gate driver receiving the first clock signal and the second clock signal and outputting gate signals; and a plurality of pixels turned on or off in response to the gate signals and thus displaying images, wherein the constant voltage output device outputs a constant voltage whose value is determined by a voltage difference between a reference terminal and an input terminal of the constant voltage output device, and the temperature-sensing device provides an input voltage whose value varies according to the change in the ambient temperature, wherein the voltage difference between the refereType: GrantFiled: August 27, 2009Date of Patent: October 16, 2012Assignee: Samsung Electronics Co., Ltd.Inventors: Eun-Woo Jeong, Sang-Hoon Park, Hwan-Jun Sung
-
Patent number: 8284181Abstract: The present invention provides a display device which includes a common electrode drive circuit having the single channel constitution which can miniaturize a circuit scale without increasing elements compared to a conventional display device. A display device includes a plurality of pixels and a common electrode drive circuit. The common electrode drive circuit includes a plurality of basic circuits, wherein the basic circuit includes a first circuit which latches a first input signal at a point of time that a clock signal is changed to a first voltage level from a second voltage level; a second circuit which latches a second input signal at the point of time that the clock signal is changed to the first voltage level from the second voltage level; a first switching circuit which is turned on based on the first circuit and a second switching circuit which is turned on based on the voltage second circuit.Type: GrantFiled: January 8, 2010Date of Patent: October 9, 2012Assignees: Hitachi Displays, Ltd., Panasonic Liquid Crystal Display Co., Ltd.Inventors: Takayuki Nakao, Hideo Sato, Masahiro Maki, Toshio Miyazawa
-
Patent number: 8284143Abstract: A timing controller includes a frame memory capable of storing previous frame data, a comparator structured to output a selection control signal in response to comparison of the previous frame data supplied from the frame memory with current frame data, an overdriver unit structured to output a compensation data signal in response to comparison of the previous frame data and the current frame data, a saturation voltage data supplying unit structured to generate a saturation voltage data signal in response to comparison of the previous frame data and the current frame data, and an outputting unit capable of selectively outputting either the compensation data signal or the saturation voltage data signal in response to the selection control signal.Type: GrantFiled: January 18, 2008Date of Patent: October 9, 2012Assignee: Samsung Electronics Co., Ltd.Inventors: Jae-Hyoung Park, Woo-Chul Kim
-
Patent number: 8284145Abstract: The present invention discloses an LCD driver and LCD driving method for improving brightness uniformity, wherein a detection-count circuit is used to calculate a number of waiting voltage offsets of each one of data electrodes during a scanning period, convert the number of waiting voltage offsets into an offset time, shift a data electrode to an intermediate potential during the offset time, and shift the data electrode to a potential for a next piece of data after the offset time is completed. Thereby, the present invention can reduce LCD brightness non-uniformity and promote LCD quality.Type: GrantFiled: December 21, 2007Date of Patent: October 9, 2012Assignee: Sitronix Technology Corp.Inventor: Jia-Chi Zheng
-
Patent number: 8284184Abstract: The present invention directs to a method an device for avoiding image sticking, the method for avoiding image sticking is to adjust a real common electrode voltage by difference between the real common electrode voltage and an ideal common electrode voltage, said difference is obtained by acquiring a real pixel electrode voltage on a panel; the device comprises a difference generation block for generating the difference between the real common electrode and the ideal common electrode voltage and an adjusting block for adjusting the real common electrode voltage, said adjusting block comprises an enabling block for generating a common electrode voltage adjustor enabling signal, a control block for generating a common electrode voltage adjustor control signal, and a common electrode voltage adjustor for adjusting the real common electrode voltage.Type: GrantFiled: May 29, 2008Date of Patent: October 9, 2012Assignee: Beijing Boe Optoelectronics Technology Co., Ltd.Inventor: Fang Dou
-
Patent number: 8284144Abstract: A method for driving a liquid crystal display device that decreases a sticking of the display image. The liquid crystal display device includes a pixel electrode and a counter electrode. A polarity of the signal supplied to the pixel electrode is periodically inverted at the first period and the second period. The length of the first period is different from that of the second period.Type: GrantFiled: November 19, 2004Date of Patent: October 9, 2012Assignees: Hitachi Displays, Ltd., Panasonic Liquid Crystal Display Co., Ltd.Inventors: Toshiki Misonou, Toshio Maeda, Katsumi Matsumoto, Hideki Nakagawa
-
Patent number: 8284335Abstract: An electronic display device includes a display unit adapted to display an image, and a barrier unit overlapping the display unit, the barrier unit including a liquid crystal layer between first and second substrates, the first and second substrates facing each other, a common electrode between the liquid crystal layer and the first substrate, a transparent insulation layer between the liquid crystal layer and the second substrate, the transparent insulation layer having an inner surface facing the liquid crystal layer and an outer surface facing the second substrate, a plurality of first electrodes along a first direction between the outer surface of the transparent insulation layer and the second substrate, the first electrodes being spaced apart from each other along a second direction, and a plurality of second electrodes along the first direction between the inner surface of the transparent insulation layer and the first substrate.Type: GrantFiled: March 6, 2009Date of Patent: October 9, 2012Assignee: Samsung Display Co., Ltd.Inventors: Beom-Shik Kim, Ja-Seung Ku, Hui Nam, Chan-Young Park, Hyoung-Wook Jang
-
Patent number: 8279153Abstract: A liquid crystal display and a method for driving the same are disclosed. The liquid crystal display includes a timing controller generating a polarity control signal. A logic inverting period of the polarity control signal during frame periods ranging from an Nth frame period among M frame periods to 2 to 4 frame periods following the Nth frame period is longer than a logic inverting period of the polarity control signal in the other frame periods, where N is an integer equal to or larger than 4 and M is larger than N. The liquid crystal cells in one frame period of the M frame periods are charged to the data voltage whose a polarity is opposite to a polarity of the data voltage in a previous frame period of one frame period.Type: GrantFiled: November 24, 2008Date of Patent: October 2, 2012Assignee: LG Display Co., Ltd.Inventors: Hongsung Song, Woongki Min, Yonggi Son, Suhyuk Jang
-
Electro-optical device and circuit for driving electro-optical device to represent gray scale levels
Patent number: 8279152Abstract: An electro-optical device drives a plurality of pixels to represent gray scale levels based on effective voltages by dividing one frame into a plurality of fields, and includes a calculating unit that receives image data specifying gray scale values in each frame for each pixel. A voltage pattern determining unit that determines to supply a first effective voltage shifted in a variation direction, rather than a voltage according to a gray scale value specified in the image data of a later frame of the adjacent frames, in a previous field of the plurality of fields in the later frame, while determining to supply a second effective voltage shifted in a direction opposite the variation direction, rather than the voltage according to the gray scale value specified in the image data of the later frame, in a later field of the plurality of fields in the later frame, for the pixel.Type: GrantFiled: February 16, 2006Date of Patent: October 2, 2012Assignee: Seiko Epson CorporationInventor: Kiyoaki Murai -
Patent number: 8279215Abstract: A display apparatus includes a timing controller, a column driver, a row driver and a display unit. The timing controller outputs a first column clock embedded into image data during an active period, and outputs a second column clock embedded into blank data during a blank period. The column driver detects the first column clock and the image data and converts the image data into a first analog signal using the first column clock, and detects the second column clock and the blank data and converts the blank data into a second analog signal using the second column clock. The first column clock has a voltage level greater than a voltage level of the image data. The second column clock is embedded into the blank data and has a voltage level substantially the same as the voltage level of the image data.Type: GrantFiled: September 15, 2009Date of Patent: October 2, 2012Assignee: Samsung Electronics Co., Ltd.Inventors: Hyoung-Sik Nam, Jee-Hoon Jeon, Kwan-Young Oh
-
Patent number: 8274465Abstract: A liquid crystal display device includes a display section, an image signal drive circuit, a scan signal drive circuit, a common electrode potential control circuit, and a synchronous circuit. The display section has scan electrodes, image signal electrodes, a plurality of pixel electrodes arranged in a matrix, a plurality of switching elements for transmitting an image signal to the pixel electrodes, and a common electrode. The common electrode potential control circuit changes an electric potential of the common electrode into a pulse shape, after the scan signal drive circuit has scanned all the scan electrodes and the image signal has been transmitted to the pixel electrodes. Otherwise, the image signal is overdriven. Otherwise, torque for returning to a no-voltage-application state is increased.Type: GrantFiled: September 21, 2009Date of Patent: September 25, 2012Assignee: NLT Technologies, Ltd.Inventor: Kenichi Takatori
-
Patent number: 8269706Abstract: An operating unit of an LCD panel and a method for operating the same are disclosed, to improve the picture quality by removing superior polarity. The operating unit includes a plurality of data driver ICs for supplying data to the data lines of the LCD panel, a plurality of gate driver ICs for sequentially operating the gate lines of the LCD panel, and a timing controller for supplying polarity control signals having opposite polarities respectively to first and second blocks of the data driver ICs formed by dividing the data driver ICs into multiple blocks.Type: GrantFiled: March 7, 2005Date of Patent: September 18, 2012Assignee: LG Display Co., Ltd.Inventor: Kwang Hee Hwang
-
Patent number: 8264451Abstract: To provide a display panel control device capable of improving gap of moving pictures, etc., without increasing the dividing number of the backlight. The device includes: a black image insertion driving part which performs, on a display panel, black image insertion drive in which video display scanning and black image display scanning are executed in a specific period; and a light-up timing control part which controls a light-up start timing and a light-off start timing of each light source block based on a synchronous signal which synchronizes with the start timing of the video display scanning or the black image display scanning. The light-off period of the light source block is equal to or less than a period from the end of black image display scanning performed on all display lines within a block area to the start of video scanning performed on the first display line within the area.Type: GrantFiled: March 30, 2009Date of Patent: September 11, 2012Assignee: NEC CorporationInventor: Hiroaki Kimura
-
Patent number: 8264446Abstract: A driving apparatus for a display device includes a plurality of pixels arranged in a matrix, and each pixel includes first and second sub-pixels. The driving apparatus includes a memory for storing digital data, a controller for calling the digital data to output the digital data together with a clock signal and at least one selection signal, and a gray voltage generator formed of an integrated circuit to receive the digital data from the controller and to generate gray reference voltage sets. The gray voltage generator includes first and second registers for storing the digital data, a selector including a plurality of multiplexers for receiving the outputs of the first and second registers, and a converter including a plurality of digital-analog converters connected to the multiplexers. As described above, the gray voltage generator is provided in the form of a chip so that it is possible to reduce the area occupied on a printed circuit board (PCB) and to reduce the cost of the gray voltage generator.Type: GrantFiled: March 18, 2010Date of Patent: September 11, 2012Assignee: Samsung Electronics Co., Ltd.Inventors: Seung-Woo Lee, Tae-Sung Kim, Jae-Hyoung Park
-
Patent number: RE43850Abstract: As multiphase clocks to be supplied to a first gate driver that drives odd-numbered scanning lines in a liquid crystal display region and a second gate driver that drives even-numbered scanning lines, clocks, which are effective within an effective period of the image signal just before an image signal starts to be supplied to display elements for each scanning line of the liquid crystal display region, is generated and the first and second gate drivers drive switching elements in the effective period of the clock.Type: GrantFiled: July 13, 2011Date of Patent: December 11, 2012Assignee: Onanovich Group AG, LLCInventor: Koji Kikuchi