Having Compensating Pulse Patents (Class 345/78)
  • Patent number: 8325169
    Abstract: A pixel circuit provided on a substrate on which a signal line, first and second scanning lines supplying first and second control pulse signals, a fixed power line, and a variable power line are arranged includes a capacitance element, a sampling transistor connected between the signal line and one of ends of the capacitance element, where the gate of the sampling transistor is connected to the first scanning line, a drive transistor of which gate is connected to the other end, where one of a drain and a source of the drive transistor is connected to the fixed power line, an initializing transistor of which gate is connected to the second scanning line, which is connected between the other end and the other of the drain and the source, and a light emitting element connected between the variable power line and the other of the drain and the source.
    Type: Grant
    Filed: September 29, 2009
    Date of Patent: December 4, 2012
    Assignee: Sony Corporation
    Inventor: Takao Tanikame
  • Patent number: 8319708
    Abstract: A pixel for an organic light emitting diode display is disclosed. The pixel includes a capacitor configured to be charged with a voltage which compensates for the threshold voltage and mobility of the transistor driving the organic light emitting diode of the pixel.
    Type: Grant
    Filed: July 17, 2009
    Date of Patent: November 27, 2012
    Assignee: Samsung Display Co., Ltd.
    Inventors: Myoung-Hwan Yoo, Keum-Nam Kim
  • Patent number: 8319713
    Abstract: A pixel capable of compensating for deterioration of an organic light emitting diode includes an organic light emitting diode. A pixel circuit includes a first transistor controlling an amount of current supplied from a first power supply to the organic light emitting diode corresponding to a data signal. A compensating unit controls a voltage of a gate electrode of the first transistor to compensate for deterioration of the organic light emitting diode. The compensating unit includes a second transistor coupled between the gate electrode of the first transistor and the organic light emitting diode and turned off during a period of the supply of the data signal to the pixel circuit, and a feedback capacitor coupled between the second transistor and the organic light emitting diode.
    Type: Grant
    Filed: February 3, 2009
    Date of Patent: November 27, 2012
    Assignee: Samsung Display Co., Ltd.
    Inventor: Sang-Moo Choi
  • Patent number: 8310419
    Abstract: The present invention relates to a display device and a driving method thereof. The display device includes a light emitting device, a capacitor connected between a first electrical contact and a second electrical contact, a driving transistor, a switching transistor being controlled by a scanning signal to be connected between a data voltage and the first electrical contact, a first compensation transistor being controlled by a first compensation signal to be connected between the first electrical contact and a first voltage, and a second compensation transistor being controlled by a second compensation signal to be connected between the second electrical contact and a second voltage. The driving transistor includes an input terminal that is connected to a driving voltage, an output terminal that is connected to the second electrical contact, and a control terminal that is connected to the first electrical contact.
    Type: Grant
    Filed: December 26, 2008
    Date of Patent: November 13, 2012
    Assignee: Samsung Display Co., Ltd.
    Inventors: Doo-Hyung Woo, Kwang-Sub Shin, Young-Il Kim, Ji-Hye Eom
  • Patent number: 8310414
    Abstract: An information processing apparatus includes a self-luminous type display, a current value predicting unit for predicting, based on a pixel value of a next image, the value of a current required by the display that displays the next image, and a controller for controlling luminance of the display based on the predicted current value.
    Type: Grant
    Filed: September 9, 2005
    Date of Patent: November 13, 2012
    Assignee: Sony Corporation
    Inventor: Ken Tamayama
  • Patent number: 8305310
    Abstract: A display device including pixels has formed therein at least two driving blocks each made up of pixel rows, and includes: a signal line driving circuit that outputs a signal voltage to an output line disposed in each of pixel columns; and a selector circuit that provides a signal voltage outputted from the output line to one of a first signal line and a second signal line which are provided in each of the columns, provides a standard voltage from a standard voltage source to one of the two signal lines, and provides the signal voltage and the standard voltage mutually exclusively to the two signal lines. Each of the pixels includes a current control unit and an organic EL element. Pixels in the k-th driving block are connected to the first signal line and pixels in the (k+1)-th driving block are connected to the second signal line.
    Type: Grant
    Filed: April 10, 2012
    Date of Patent: November 6, 2012
    Assignee: Panasonic Corporation
    Inventors: Masafumi Matsui, Shinya Ono
  • Patent number: 8300009
    Abstract: An electrophoretic display according to the present invention includes a first reset step for applying a first voltage to electrophoretic devices such that no image is displayed and no afterimages are present in the electrophoretic devices between a first step for displaying a first image on the electrophoretic devices and a second step for displaying a second image on the electrophoretic devices and a second reset step for applying a second voltage higher than the first voltage such that no image is displayed and no afterimage is present in the electrophoretic devices at a frequency less than that at which the first reset step is performed.
    Type: Grant
    Filed: March 1, 2010
    Date of Patent: October 30, 2012
    Assignee: Seiko Epson Corporation
    Inventor: Kazunori Hiramatsu
  • Patent number: 8289245
    Abstract: The present invention provides a display device, a method for driving the same, and an electronic device capable of making ? correction function reliably even in the case where light emission luminance is low. A potential difference between the gate and the source of a transistor is corrected to a threshold voltage of the transistor. After that, while a horizontal drive circuit outputs a third voltage Vofs2, correction of mobility of the transistor starts. Subsequently, while the horizontal drive circuit outputs a second voltage Vsig, writing of a voltage according to the second voltage Vsig to the gate of the transistor is started.
    Type: Grant
    Filed: July 23, 2009
    Date of Patent: October 16, 2012
    Assignee: Sony Corporation
    Inventor: Shoji Araki
  • Patent number: 8289234
    Abstract: An Organic Light Emitting Display (OLED) that is capable of decreasing the number of output lines for a data driver using a demultiplexer, displaying an image with uniform brightness, and adjusting white balance includes: a plurality of red, green and blue sub-pixels, and each sub-pixel is provided with an auxiliary capacitor to compensate a decreased driving voltage. The respective auxiliary capacitors are different in capacitance according to emission efficiency of the red, green and blue sub-pixels. The auxiliary capacitor of the green sub-pixel has a larger capacitance than the auxiliary capacitor of the red sub-pixel, and the auxiliary capacitor of the red sub-pixel has a larger capacitance than the auxiliary capacitor of the blue sub-pixel. This enables the white balance to be adjusted with the same data voltage.
    Type: Grant
    Filed: July 18, 2006
    Date of Patent: October 16, 2012
    Assignee: Samsung Display Co., Ltd.
    Inventor: Yang-Wan Kim
  • Patent number: 8289244
    Abstract: A pixel circuit has a light emitting element and a driver electrically connected to the light emitting element. A reverse bias voltage is applied to the driver to reduce a shift amount of a threshold voltage of the driver.
    Type: Grant
    Filed: June 26, 2007
    Date of Patent: October 16, 2012
    Assignee: LG Display Co., Ltd.
    Inventors: Taro Hasumi, Yoshinao Kobayashi, Keigo Kanoh
  • Patent number: 8289311
    Abstract: The display device may include a data aligning part that analyzes a gray level of input data and inserts black data into frame data having less than a designated reference gray level; and a driver that displays the data from the data aligning part in a display panel.
    Type: Grant
    Filed: December 5, 2006
    Date of Patent: October 16, 2012
    Assignee: LG Display Co., Ltd.
    Inventor: Sung Hak Jo
  • Patent number: 8284130
    Abstract: The inventors found out that in the case of performing a low gray scale display in which a very small amount of current is supplied to a light emitting element, variations in threshold voltages of driving transistors become notable since the gate-source voltage is low. In view of this, the invention provides a display device in which variations in the threshold voltages of the driving transistors are reduced even in the low gray scale display, and a driving method thereof. According to the invention, a gate-source voltage of the driving transistor is set higher in the low gray scale display than that in the high gray scale display. As one mode to achieve this, different power source lines are provided for the low gray scale display and the high gray scale display and their potentials are set to be different.
    Type: Grant
    Filed: August 17, 2007
    Date of Patent: October 9, 2012
    Assignee: Semiconductor Energy Laboratory Co., Ltd.
    Inventors: Keisuke Miyagawa, Hajime Kimura
  • Patent number: 8279143
    Abstract: A system and method are disclosed for determining a pixel capacitance. The pixel capacitance is correlated to a pixel age to determine a current correction factor used for compensating the pixel drive current to account for luminance degradation of the pixel that results from the pixel aging.
    Type: Grant
    Filed: July 11, 2011
    Date of Patent: October 2, 2012
    Assignee: Ignis Innovation Inc.
    Inventors: Arokia Nathan, Gholamreza Chaji
  • Patent number: 8274457
    Abstract: A driving device of a light emitting unit is provided. The driving device includes a driving circuit, a switch, a capacitor, and a compensation circuit. The driving circuit has a control terminal and a driving terminal connected to the light emitting unit. The driving circuit determines a driving current according to the voltage on the control terminal. The switch has a first end for receiving a data voltage, a second end connected to the light emitting unit, and a control end for receiving a scan voltage. The capacitor has a first end connected to the control terminal of the driving circuit and a second end connected to the second end of the switch. The compensation circuit has an output terminal connected to the first end of the capacitor. The compensation circuit supplies a reset voltage to the first end of the capacitor when the switch is turned on.
    Type: Grant
    Filed: March 23, 2010
    Date of Patent: September 25, 2012
    Assignee: Au Optronics Corporation
    Inventor: Tsung-Ting Tsai
  • Patent number: 8269798
    Abstract: A method of controlling a passive matrix display having rows and columns of pixels including receiving an input image signal; determining drive signals for at least a first image field and a second image field; calculating a value that is correlated to a change in the total capacitive charge of the pixels that will occur between the display of the first image field and the second image field for at least one column of the passive-matrix, electro-luminescent display; adjusting at least one of the drive signals within first or second image fields to compensate for the change in total capacitive charge; and providing adjusted drive signals for each pixel.
    Type: Grant
    Filed: July 18, 2007
    Date of Patent: September 18, 2012
    Assignee: Global OLED Technology LLC
    Inventors: Michael E. Miller, Andrew D. Arnold, John F. Hamilton, Jr.
  • Patent number: 8264431
    Abstract: Embodiments of the present invention provide for an array, and corresponding method of forming an array, that includes a plurality of light emitting devices. The light emitting devices are disposed over a substrate, and a photodetector detects light emitted through the substrate from the light emitting devices. Further, a substantially constant brightness may be maintained in a plurality of light emitting devices disposed over the upper surface of a substrate in an array. Light emitted through the substrate from each of the light emitting devices is measured, and the voltage level applied to each of the light emitting devices is varied to maintain a substantially constant brightness level of light emitted from the light emitting devices.
    Type: Grant
    Filed: October 23, 2003
    Date of Patent: September 11, 2012
    Assignee: Massachusetts Institute of Technology
    Inventors: Vladimir Bulovic, Jonathan R. Tischler, Jennifer Yu
  • Patent number: 8253663
    Abstract: A display apparatus and display driving method. A selective scan operation is performed on pixel circuits in row units, and a threshold-voltage correction operation is also performed to correct variations of the threshold voltage of respective pixel circuit driving transistors. Before performing the threshold-voltage correction operation in a horizontal scan period, a preparatory operation is performed in order to fix each of the electric potentials appearing on the gate and the source of the driving transistor at a predetermined level.
    Type: Grant
    Filed: March 19, 2008
    Date of Patent: August 28, 2012
    Assignee: Sony Corporation
    Inventors: Takayuki Taneda, Tetsuro Yamamoto, Yukihito Iida, Katsuhide Uchino
  • Patent number: 8248334
    Abstract: Disclosed herein is a method of driving an organic electroluminescence emission portion, the method including the steps of: applying a first node initialization voltage to corresponding one of the data lines, and supplying the video signal instead of the first node initialization voltage for a predetermined scanning time period, applying the first node initialization voltage from the corresponding one of the data lines to the first node through the write transistor held in an ON state for initializing the potential at the first node, and holding a state of applying the first node initialization voltage from the corresponding one of the data lines to the first node through the write transistor held in an ON state for holding the potential at the first node.
    Type: Grant
    Filed: August 26, 2008
    Date of Patent: August 21, 2012
    Assignee: Sony Corporation
    Inventors: Naobumi Toyomura, Tetsuro Yamamoto, Katsuhide Uchino
  • Patent number: 8232932
    Abstract: The present invention suppresses the generation of a leak current that accompanies the polarity inversion of the voltage waveform of the opposing electrode. The display device that performs display by sequentially scanning a plurality of scan signal lines in a single cycle period comprises: a plurality of data signal lines that intersect the scan signal lines; a pixel electrode that is connected to the data signal lines; and an opposing electrode that is disposed opposite the pixel electrode and for which the polarity of an application voltage is inverted in each of the cycle periods. The cycle period includes a scan period in which one full scan of the scan signal lines is performed and a non-scan period in which the scan signal lines are not scanned.
    Type: Grant
    Filed: September 27, 2007
    Date of Patent: July 31, 2012
    Assignee: Citizen Holdings Co., Ltd.
    Inventors: Rintarou Takahashi, Takashi Akiyama
  • Patent number: 8232935
    Abstract: Disclosed herein is a display apparatus, including: a pixel array section including a plurality of pixels, a writing transistor, a driving transistor, a first switching transistor, a holding capacitor, and a second switching transistor; a first scanning section configured to drive the writing transistor in a unit of a row of the pixels; a second scanning section configured to drive the switching transistors in synchronism with scanning by the first scanning section; and a third scanning section configured to control the second switching transistors to a non-conducting state within a period after the image signal is written by the writing transistor until the signal writing period of the same row of the pixels ends but to a conducting state within any other period.
    Type: Grant
    Filed: May 21, 2008
    Date of Patent: July 31, 2012
    Assignee: Sony Corporation
    Inventors: Yutaka Mitomi, Masatsugu Tomida, Katsuhide Uchino
  • Patent number: 8232939
    Abstract: A system and method for driving an AMOLED display is provided. The AMOLED display includes a plurality of pixel circuits. A voltage-programming scheme, a current-programming scheme or a combination thereof is applied to drive the display. Threshold shift information, and/or voltage necessary to obtain hybrid driving circuit may be acquired. A data sampling may be implemented to acquire a current/voltage relationship. A feedback operation may be implemented to correct the brightness of the pixel.
    Type: Grant
    Filed: February 14, 2012
    Date of Patent: July 31, 2012
    Assignee: Ignis Innovation, Inc.
    Inventors: Arokia Nathan, Rick Huang, Stefan Alexander
  • Patent number: 8223094
    Abstract: Display devices and methods capable of reversing brightness deterioration in electroluminescence elements while maintaining display quality, with simple pixel circuits and no manufacturing yield reduction, are provided. A display device includes luminescence pixels that each include a driving transistor, a luminescence element, and a switching transistor which switches between conduction and non-conduction states between a data line and the luminescence element. A data driving circuit supplies a signal voltage to the data line and a bias supplying circuit supplies a specified bias voltage to the data line. A control unit applies the specified bias voltage to an anode or cathode of the luminescence element by causing conduction between the data line and the data driving circuit, causing non-conduction between the data line and the bias supplying circuit, and turning the switching transistor ON, all within a period in which a signal current does not flow to the luminescence element.
    Type: Grant
    Filed: February 26, 2010
    Date of Patent: July 17, 2012
    Assignee: Panasonic Corporation
    Inventors: Mika Nakamura, Kenichi Masumoto
  • Patent number: 8217866
    Abstract: A data driving circuit capable of displaying images having uniform brightness. The present invention provides a data driving circuit of a display device having: at least one current sinking unit for controlling a predetermined current to flow in a data line; at least one voltage generating unit for resetting voltage values of enhancement voltages using a compensation voltage generated when the predetermined current flows; at least one digital-analog converter for selecting as a data signal one of the enhancement voltages to correspond to a digital value of externally supplied data; at least one boosting unit for boosting a voltage value of the data signal; and at least one switching unit for providing the data line with the boosted data signal.
    Type: Grant
    Filed: July 20, 2006
    Date of Patent: July 10, 2012
    Assignees: Samsung Mobile Display Co., Ltd., IUCF-HYU (Industry-University Cooperation Foundation Hanyang University)
    Inventors: Do Hyung Ryu, Bo Yong Chung, Oh Kyong Kwon
  • Patent number: 8217862
    Abstract: Disclosed herein is a display apparatus, including: a pixel array section having a plurality of pixels each including an electro-optical element, a writing transistor, a driving transistor, and a holding capacitor; a power supply scanning circuit; and a signal outputting circuit; wherein the power supply scanning circuit is operable to supply a second power supply potential to initialize the potential of a second electrode of the driving transistor and then change over the potential of a power supply line to a first power supply potential; and the signal outputting circuit is operable to output, when the writing transistor is in a conducting state, a first reference potential, supply, midway while a threshold value correction process is carried out, a second reference potential, output a third reference potential within a period within which the writing transistor remains in the conducting state, and output a image signal after the threshold correction process ends.
    Type: Grant
    Filed: October 1, 2008
    Date of Patent: July 10, 2012
    Assignee: Sony Corporation
    Inventors: Tetsuo Minami, Masatsugu Tomida
  • Patent number: 8207918
    Abstract: During a first period of a set period, a reset switch element of each pixel is turned on to converge a voltage at a control electrode of a TFT to a predetermined voltage, and a step signal having a first voltage level is supplied from a step signal generation circuit. During a second period of the set period, the reset switch element is turned off, and a step signal having a second voltage level is supplied from the step signal generation circuit, whereby a voltage exceeding a second power supply voltage or a voltage exceeding a voltage range supplied from a signal driver section is input as a characteristic value set voltage to the control electrode. Accordingly, even when a relationship between a gate voltage and a drain current of the thin film transistor exhibits a hysteresis characteristic, uniform display can be achieved.
    Type: Grant
    Filed: June 9, 2009
    Date of Patent: June 26, 2012
    Assignees: Hitachi Displays, Ltd., Panasonic Liquid Crystal Display Co., Ltd.
    Inventors: Tohru Kohno, Takahide Kuranaga, Hiroshi Kageyama, Hajime Akimoto
  • Patent number: 8199074
    Abstract: A representative system for displaying images comprises a pixel array, a conversion circuit, a memory device, and a compensation circuit. The pixel array has a plurality of pixels, each having at least one organic light emitting element equipped with a sensing unit which retrieves display information when the organic light emitting element retrieves a test signal. The conversion circuit determines a display parameter of each organic light emitting element according to the test signal and the display information of each organic light emitting element. The memory device stores the display parameter of each organic light emitting element. The compensation circuit modifies a video signal in accordance with the display parameters stored in the memory device.
    Type: Grant
    Filed: August 11, 2006
    Date of Patent: June 12, 2012
    Assignee: Chimei Innolux Corporation
    Inventors: Shou-Cheng Wang, Shih-Chang Chang
  • Publication number: 20120139894
    Abstract: A system and method for driving an AMOLED display is provided. The AMOLED display includes a plurality of pixel circuits. A voltage-programming scheme, a current-programming scheme or a combination thereof is applied to drive the display. Threshold shift information, and/or voltage necessary to obtain hybrid driving circuit may be acquired. A data sampling may be implemented to acquire a current/voltage relationship. A feedback operation may be implemented to correct the brightness of the pixel.
    Type: Application
    Filed: February 14, 2012
    Publication date: June 7, 2012
    Applicant: Ignis Innovation, Inc.
    Inventors: Arokia Nathan, Rick Huang, Stefan Alexander
  • Patent number: 8194013
    Abstract: An organic light emitting display capable of minimizing power consumption. The organic light emitting display includes a plurality of pixels positioned at intersections of data lines and scan lines includes the pixels including driving transistors positioned in an effective display region to control an amount of current that flows from a first power source to a second power source, a data driver for supplying data signals to the data lines, a scan driver supplying scan signals to the scan lines, a first power source generator generating the first power source, a second power source generator generating the second power source, and a voltage controller controlling the second power source generator so that voltage of the second power source is changed in response to a first voltage applied to an organic light emitting diode (OLED) included in a specific pixel when a data signal corresponding to specific brightness is supplied from the data driver to the specific pixel.
    Type: Grant
    Filed: July 20, 2009
    Date of Patent: June 5, 2012
    Assignee: Samsung Mobile Display Co., Ltd.
    Inventor: Sang-Moo Choi
  • Patent number: 8188946
    Abstract: A method and system for compensation for luminance degradation in electro-luminance devices is provided. The system includes a pixel circuit having a light emitting device, a storage capacitor, a plurality of transistors, and control signal lines to operate the pixel circuit. The storage capacitor is connected or disconnected to the transistor and a signal line(s) when programming and driving the pixel circuit.
    Type: Grant
    Filed: September 12, 2006
    Date of Patent: May 29, 2012
    Assignee: Ignis Innovation Inc.
    Inventors: Arokia Nathan, G. Reza Chaji, Shahin Jafarabadiashtiani
  • Patent number: 8174466
    Abstract: Disclosed herein is a display device including: a pixel array unit having pixel circuits arranged in a form of a matrix; and a control unit having a writing scanning unit for outputting, to the sampling transistor, a writing scanning pulse. The control unit effects control to supply a control input terminal of the drive transistor with a fixed potential for a threshold value correcting operation for retaining a voltage corresponding to a threshold voltage of the drive transistor in the storage capacitor. When setting a voltage across the storage capacitor to the threshold voltage of the drive transistor by repeating the threshold value correcting operation a plurality of times on a time division basis, the control unit effects control to perform each the threshold value correcting operation and the sampling transistor to a conducting state.
    Type: Grant
    Filed: February 12, 2008
    Date of Patent: May 8, 2012
    Assignee: Sony Corporation
    Inventors: Naobumi Toyomura, Katsuhide Uchino, Tetsuro Yamamoto
  • Patent number: 8164549
    Abstract: An electronic circuit drives a driven element. The electronic circuit includes a signal line, a unit circuit connected to the signal line, and a voltage supply line. The unit circuit includes a transistor, a switch, and a capacitive element. The transistor includes a gate terminal, a first terminal, a second terminal connected to the voltage supply line, and a channel between the first and second terminals. The switch controls electrical connection between the gate terminal and one of the first and second terminals. A conductive state between the first and second terminals is controlled by a gate voltage applied to the gate terminal. During a first period, the switch is changed from an off state to an on state. During a second period, the switch is changed to an off state.
    Type: Grant
    Filed: October 2, 2007
    Date of Patent: April 24, 2012
    Assignee: Seiko Epson Corporation
    Inventor: Takashi Miyazawa
  • Patent number: 8159425
    Abstract: The present invention relates to a method and apparatus for driving an electro-luminescence display panel capable of doing an aging operation upon driving. A method of driving an electro-luminescence display panel according to the present invention includes: a scan period when electro-luminescence cells formed at a cross of both a plurality of scan lines and a plurality of data lines are line-sequentially emitted; and an aging period when an aging is performed in the electro-luminescence cells at the same time by applying a reverse bias, wherein the scan period and the aging period are repeated for each frame.
    Type: Grant
    Filed: March 16, 2009
    Date of Patent: April 17, 2012
    Assignee: LG Electronics Inc.
    Inventors: Hyo Dae Bae, Hak Su Kim
  • Patent number: 8159482
    Abstract: For making outputs of a drive circuits accurate, the drive circuit is composed of a plurality of current signal generation circuits for outputting a current signal to each of a plurality of output units, a current signal output line to which outputs of the plurality of current signal generation circuits are commonly connected, a correction value output circuit for outputting a correction value obtained by evaluating the output of one or more specific circuits of the plurality of current signal generation circuits on a basis of current values output through the current signal output line, and a correction circuit for correcting an image signal supplied to the current signal generation circuits by means of the correction value.
    Type: Grant
    Filed: March 5, 2008
    Date of Patent: April 17, 2012
    Assignee: Canon Kabushiki Kaisha
    Inventors: Somei Kawasaki, Fujio Kawano, Masami Iseki
  • Patent number: 8154539
    Abstract: For making outputs of a drive circuits accurate, the drive circuit is composed of a plurality of current signal generation circuits for outputting a current signal to each of a plurality of output units, a current signal output line to which outputs of the plurality of current signal generation circuits are commonly connected, a correction value output circuit for outputting a correction value obtained by evaluating the output of one or more specific circuits of the plurality of current signal generation circuits on a basis of current values output through the current signal output line, and a correction circuit for correcting an image signal supplied to the current signal generation circuits by means of the correction value.
    Type: Grant
    Filed: March 5, 2008
    Date of Patent: April 10, 2012
    Assignee: Canon Kabushiki Kaisha
    Inventors: Somei Kawasaki, Fujio Kawano, Masami Iseki
  • Patent number: 8154483
    Abstract: Disclosed is an image display wherein luminance change due to change of the light-emitting device over time is compensated while suppressing affects of characteristics change in the drive transistor. Specifically disclosed is an image display comprising a plurality of pixels, wherein each pixel has a light-emitting device (OLED) which emits light when current is passed therethrough, a driver device (Td) for controlling light emission of the light-emitting device, and a control circuit (A) which is electrically connected to the light-emitting device and the driver device, and directly or indirectly detects the voltage applied to the light-emitting device at least during when the light-emitting device is emitting light and reflects the detection results to the driver device.
    Type: Grant
    Filed: November 17, 2006
    Date of Patent: April 10, 2012
    Assignee: LG Display Co., Ltd.
    Inventors: Shinji Takasugi, Osamu Tokuhiro, Kaoru Kusafuka, Yutaka Kuba
  • Patent number: 8138998
    Abstract: A device for controlling an electroluminescent matrix display by successive selection of its lines, including a column control circuit having circuitry capable of placing, at the beginning of the selection of a line, the display column at a precharge voltage based on the operating voltage of the previous line, the column control circuit also having circuitry capable of modifying the precharge voltage according to the difference between luminance instructions of the previous line and those of the selected line.
    Type: Grant
    Filed: April 11, 2008
    Date of Patent: March 20, 2012
    Assignee: STMicroelectronics S.A.
    Inventors: Céline Mas, Corinne Ianigro, Hervé Pierrot
  • Patent number: 8130180
    Abstract: A pixel circuit is disclosed in the present invention, which includes an OLED, a current-driving unit receiving a signal current on a data line during a programming period to provide a corresponding driving current to the OLED, a first switch coupled between the data line and the current-driving unit and turned on during the programming period to conduct the signal current, and a constant current unit providing a constant current on the data line during a pre-programming period and the programming period. The present invention also discloses an apparatus for driving a display, including a scan-driving circuit, a data-driving circuit, and plural constant current units. A method for driving a pixel having an OLED is also disclosed, which includes the steps of receiving a signal current on a data line during a programming period to provide a corresponding driving current to the OLED, and providing a constant current on the data line during a pre-programming period and the programming period.
    Type: Grant
    Filed: January 9, 2007
    Date of Patent: March 6, 2012
    Assignee: Himax Technologies Limited
    Inventors: Chen Yu Wang, Yu Wen Chiou
  • Patent number: 8130182
    Abstract: An electroluminescent (EL) subpixel driven by a digital-drive scheme has a readout transistor driven by a current source when the drive transistor is non-conducting. This produces an emitter-voltage signal from which an aging signal representing the efficiency of the EL emitter can be computed. The aging signal is used to determine the loss in current of the subpixel when active, and an input signal is adjusted to provide increased on-time to compensate for voltage rise and efficiency loss of the EL emitter. Variations due to temperature can also be compensated for.
    Type: Grant
    Filed: December 18, 2008
    Date of Patent: March 6, 2012
    Assignee: Global OLED Technology LLC
    Inventors: Charles I. Levey, Felipe A. Leon, John W. Hamer, Gary Parrett, Christopher J. White
  • Patent number: 8130181
    Abstract: A OLED display and a driving method thereof are disclosed.
    Type: Grant
    Filed: December 15, 2008
    Date of Patent: March 6, 2012
    Assignee: LG Display Co., Ltd.
    Inventors: Chang Hoon Jeon, Jung Chul Kim, Ho Young Lee
  • Patent number: 8130178
    Abstract: In a display apparatus including a switching transistor, a correction voltage for eliminating an effect of a variation in a characteristic of a driving transistor is stored in a storage capacitor. The switching transistor is disposed between one current terminal of the driving transistor and a light emitting element. The switching transistor turns off during the non-light emission period thereby to electrically disconnect the light emitting element from the one current terminal of the driving transistor thereby preventing a leakage current from flowing through the light emitting element during the period in which the correction unit operates, and thus preventing the correction voltage from having an error due to the leakage current.
    Type: Grant
    Filed: July 20, 2011
    Date of Patent: March 6, 2012
    Assignee: Sony Corporation
    Inventors: Junichi Yamashita, Masatsugu Tomida, Katsuhide Uchino
  • Patent number: 8115707
    Abstract: A system and method for driving an AMOLED display is provided. The AMOLED display includes a plurality of pixel circuits. A voltage-programming scheme, a current-programming scheme or a combination thereof is applied to drive the display. Threshold shift information, and/or voltage necessary to obtain hybrid driving circuit may be acquired. A data sampling may be implemented to acquire a current/voltage relationship. A feedback operation may be implemented to correct the brightness of the pixel.
    Type: Grant
    Filed: June 28, 2005
    Date of Patent: February 14, 2012
    Assignee: Ignis Innovation Inc.
    Inventors: Arokia Nathan, Rick Huang, Stefan Alexander
  • Publication number: 20120026146
    Abstract: A pixel to compensate for the deterioration of an organic light emitting diode, the pixel including an organic light emitting diode; a pixel circuit including a driving transistor controlling an amount of current supplied to the organic light emitting diode; and a compensator compensating for the deterioration of the organic light emitting diode by using on-voltage applied when current flows in the organic light emitting diode and off-voltage applied when current does not flow in the organic light emitting diode; wherein the compensator includes: a compensating capacitor having a second terminal connected to a gate electrode of the driving transistor; and a first compensating transistor connected between a first terminal of the compensating capacitor and an anode electrode of the organic light emitting diode.
    Type: Application
    Filed: January 12, 2011
    Publication date: February 2, 2012
    Applicant: Samsung Mobile Display Co., Ltd.
    Inventor: Yang-Wan KIM
  • Patent number: 8094094
    Abstract: The present invention relates to a light emitting device for preventing a cross-talk phenomenon and a pectinated pattern. The light emitting device includes data lines, scan lines, pixels and discharging circuit. The data lines are disposed in a first direction. The scan lines are disposed in a second direction different from the first direction. The pixels are formed in cross areas of the data lines and the scan lines. The discharging circuit discharges respectively a first data line and a second data line of the data lines to a first discharge voltage and a second discharge voltage during a first sub-discharging time of a discharging time, and couple the first data line to the second data line during a second sub-discharging time of the discharging time. Here, the second discharge voltage has different magnitude from the first discharge voltage.
    Type: Grant
    Filed: October 5, 2006
    Date of Patent: January 10, 2012
    Assignee: LG Display Co., Ltd.
    Inventor: Ji Hun Kim
  • Patent number: 8063857
    Abstract: When an organic EL display apparatus enables display of a standard luminance mode and a high luminance mode, it takes long time to reset the gate potential of the OLED drive TFT to a given value in a standard mode. In the reset operation of the gate potential of an OLED drive TFT at the time of writing an image signal, in a standard mode, a precharge current is allowed to flow in the OLED element for a short period before the reset operation to set an initial value of the gate potential of the OLED drive TFT to be close to a supply potential or a reference potential. With the above operation, the variation of the OLED drive TFT gate potential after resetting is reduced. As a result, the light emitting period during one frame can be extended. Also, since a blanking period can be extended, it is possible to measure the characteristic of the OLED element by using the blanking period.
    Type: Grant
    Filed: December 21, 2007
    Date of Patent: November 22, 2011
    Assignee: Hitachi Displays, Ltd.
    Inventors: Tohru Kohno, Mitsuhide Miyamoto, Hajime Akimoto
  • Publication number: 20110279488
    Abstract: A system and method are disclosed for determining a pixel capacitance. The pixel capacitance is correlated to a pixel age to determine a current correction factor used for compensating the pixel drive current to account for luminance degradation of the pixel that results from the pixel aging.
    Type: Application
    Filed: July 11, 2011
    Publication date: November 17, 2011
    Applicant: Ignis Innovation Inc.
    Inventors: Arokia Nathan, Gholamreza Chaji
  • Patent number: 8055072
    Abstract: The invention provides image display panels. The image display panel comprises a histogram generator, a tone slope generator, and an image transformer. The histogram generator receives an original image, counts the pixels of different gray levels to generate a histogram distribution of the original image, and compares the pixel counts at every gray level with a first threshold count to identify the peaks of the histogram distribution. The tone slope generator generates a tone slope based on the histogram distribution and peaks of the histogram distribution. The image transformer transforms the original image into a modified image based on the tone slope.
    Type: Grant
    Filed: November 27, 2007
    Date of Patent: November 8, 2011
    Assignee: Himax Technologies Limited
    Inventors: Shing-Chia Chen, Ling-Hsiu Huang
  • Patent number: 8044984
    Abstract: A method for driving an organic light emitting display (OLED) panel having a plurality of organic light emitting diodes is provided. The organic light emitting diodes are coupled to a plurality of segment lines and a plurality of common lines in a matrix structure. The organic light emitting diodes coupled to the same common lines are divided into a plurality of groups according to colors of the OLED panel. Driving currents are provided to the organic light emitting diodes of the groups according to a plurality of pulse width modulation (PWM) manners. The PWM manners generate waveforms having pulse width corresponding to grayscale in a period, wherein each PWM manner corresponds to different colors of the OLED panel.
    Type: Grant
    Filed: March 27, 2008
    Date of Patent: October 25, 2011
    Assignee: Himax Technologies Limited
    Inventors: Kuo-Tung Hsu, Wei-Jen Chang
  • Patent number: 8044891
    Abstract: Systems and methods for providing threshold voltage compensation of pixels are provided. A representative system incorporates first switching element and a voltage compensation driver. The first switching element is operative to transfer a data signal. The voltage compensation driver is operative to generate a compensation voltage according to a reference signal and output a driving current according to the data signal and the compensation voltage.
    Type: Grant
    Filed: August 5, 2005
    Date of Patent: October 25, 2011
    Assignee: Chimei Innolux Corporation
    Inventor: Du-Zen Peng
  • Patent number: 8035584
    Abstract: An organic light emitting display and an image compensation method improves the Long Range Uniformity (LRU) of the output image by displaying the identical image when the identical image is input to each pixel, by measuring the luminance, chromaticity coordinates and color temperature after an organic light emitting display panel is fabricated, by storing the compensation values thereof in a memory in the form of a look-up table in advance, and by compensating one of a power supply voltage, a data voltage and a light emission time.
    Type: Grant
    Filed: April 23, 2007
    Date of Patent: October 11, 2011
    Assignee: Samsung Mobile Display Co., Ltd.
    Inventor: Jin-Woung Jung
  • Patent number: RE43354
    Abstract: A driving circuit for an electro-luminescence (EL) cell includes an EL cell, and a supply circuit selectively applying current to the EL cell based on a pixel signal from a data line. A control circuit controls current flow from the supplying circuit to the EL cell such that an amount of current for discriminating between gray scale levels is approximately tens of micro-amps.
    Type: Grant
    Filed: April 30, 2004
    Date of Patent: May 8, 2012
    Assignee: LG Display Co., Ltd.
    Inventor: Sung Joon Bae