Patents by Inventor Tetsurou Nakamura

Tetsurou Nakamura has filed for patents to protect the following inventions. This listing includes patent applications that are pending as well as patents that have already been granted by the United States Patent and Trademark Office (USPTO).

  • Patent number: 9275572
    Abstract: Display device includes: a power supplying unit which outputs at least a high-side or low-side output potential; an organic EL display unit which includes pixels and receives power supply from the power supplying unit; two or more detecting lines for transmitting a high-side or low-side applied potential applied to two or more pixels; a relay unit which outputs the high-side or low-side applied potentials transmitted by the detecting lines, to output lines fewer in number than the detecting lines; and a regulating unit which regulates at least the high-side or low-side output potential to be outputted by the power supplying unit, such that any one of potential difference between a reference potential and the high-side applied potential from the relay unit, potential difference between the reference potential and the low-side applied potential, and potential difference between the high-side applied potential and the low-side applied potential reaches a predetermined potential difference.
    Type: Grant
    Filed: May 9, 2012
    Date of Patent: March 1, 2016
    Assignee: JOLED INC.
    Inventors: Yosuke Izawa, Toshiyuki Kato, Kouhei Ebisuno, Shinya Ono, Tetsurou Nakamura
  • Patent number: 9117406
    Abstract: A display apparatus is provided which optimally restores decreased luminance and extends a life of a light emitting element. The display apparatus includes a memory that stores a plurality of trap levels in association with a plurality of use durations of the light emitting element. An obtainer determines one of the plurality of use durations of the light emitting element. A controller reads, from the memory, one of the plurality of trap levels associated with the one of the plurality of use durations, and removes a charge from the light emitting element by application of a reverse bias voltage having a level associated with the one of the plurality of trap levels. The controller changes the level of the reverse bias voltage which is applied to the light emitting element so that as the one of the plurality of use durations increases, the level of the reverse bias voltage increases.
    Type: Grant
    Filed: May 23, 2014
    Date of Patent: August 25, 2015
    Assignee: JOLED INC.
    Inventors: Tetsurou Nakamura, Kenichi Masumoto
  • Patent number: 8890778
    Abstract: A display device includes an organic EL element and a capacitor. A driving transistor is connected to an anode of the organic EL element and passes a current to the organic EL element. The current corresponds to a voltage held in the capacitor. A first switch is between the capacitor and a data line, and the data line supplies the voltage to the capacitor. A voltage detector is connected to the data line for detecting an anode voltage applied to the organic EL element. A second switch is between the anode and the data line. A controller turns on the first switch, causes the organic EL element to emit light, and causes the voltage detector to detect the anode voltage by turning off the first switch and turning on the second switch while the organic EL element is emitting light.
    Type: Grant
    Filed: June 28, 2013
    Date of Patent: November 18, 2014
    Assignee: Panasonic Corporation
    Inventors: Hiroshi Shirouzu, Tetsurou Nakamura
  • Publication number: 20140252957
    Abstract: A display apparatus is provided which optimally restores decreased luminance and extends a life of a light emitting element. The display apparatus includes a memory that stores a plurality of trap levels in association with a plurality of use durations of the light emitting element. An obtainer determines one of the plurality of use durations of the light emitting element. A controller reads, from the memory, one of the plurality of trap levels associated with the one of the plurality of use durations, and removes a charge from the light emitting element by application of a reverse bias voltage having a level associated with the one of the plurality of trap levels. The controller changes the level of the reverse bias voltage which is applied to the light emitting element so that as the one of the plurality of use durations increases, the level of the reverse bias voltage increases.
    Type: Application
    Filed: May 23, 2014
    Publication date: September 11, 2014
    Applicant: PANASONIC CORPORATION
    Inventors: Tetsurou NAKAMURA, Kenichi MASUMOTO
  • Patent number: 8830148
    Abstract: An organic electroluminescence display device includes a display panel including pixels. The pixels each include a light-emitter, driver and capacitor. A storage is configured to store a correction parameter for each of the pixels for correcting, in accordance with characteristics of each of the pixels, an image signal input from an external source. A controller is configured to, for each pixel of the pixels, obtain a corrected signal voltage by reading the correction parameter corresponding to the pixel from the storage and multiplying the image signal corresponding to the pixel by the correction parameter corresponding to the pixel. The storage is configured to store a gain and not an offset as the correction parameter.
    Type: Grant
    Filed: February 23, 2012
    Date of Patent: September 9, 2014
    Assignee: Panasonic Corporation
    Inventors: Yasuo Segawa, Tetsurou Nakamura, Shinya Ono
  • Patent number: 8749457
    Abstract: A method of manufacturing an organic electroluminescence display includes preparing a substrate including pixels. The pixels each include a drive transistor and a capacitor. The capacitor of a subject pixel is caused to hold a voltage which corresponds to a threshold voltage of the drive transistor, and the voltage is read. A first signal voltage is obtained by adding a first correction parameter of the subject pixel to a second signal voltage corresponding to a single gradation level belonging to an intermediate gradation region or a high gradation region of representative voltage-luminance characteristics. The first signal voltage is applied to the driver of the subject pixel, and a luminance emitted by the subject pixel is measured. A second correction parameter with which the luminance emitted by the subject pixel becomes a standard luminance is calculated.
    Type: Grant
    Filed: February 23, 2012
    Date of Patent: June 10, 2014
    Assignee: Panasonic Corporation
    Inventors: Yasuo Segawa, Tetsurou Nakamura, Shinya Ono
  • Publication number: 20130285889
    Abstract: A display device includes an organic EL element and a capacitor. A driving transistor is connected to an anode of the organic EL element and passes a current to the organic EL element. The current corresponds to a voltage held in the capacitor. A first switch is between the capacitor and a data line, and the data line supplies the voltage to the capacitor. A voltage detector is connected to the data line for detecting an anode voltage applied to the organic EL element. A second switch is between the anode and the data line. A controller turns on the first switch, causes the organic EL element to emit light, and causes the voltage detector to detect the anode voltage by turning off the first switch and turning on the second switch while the organic EL element is emitting light.
    Type: Application
    Filed: June 28, 2013
    Publication date: October 31, 2013
    Applicant: PANASONIC CORPORATION
    Inventors: Hiroshi SHIROUZU, Tetsurou NAKAMURA
  • Patent number: 8547307
    Abstract: A display device includes an organic EL element and a capacitor. A driving transistor is connected to an anode of the organic EL element and passes a current to the organic EL element. The current corresponds to a voltage held in the capacitor. A first switch is between the capacitor and a data line, and the data line supplies the voltage to the capacitor. A voltage detector is connected to the data line for detecting an anode voltage applied to the organic EL element. A second switch is between the anode and the data line. A controller turns on the first switch, causes the organic EL element to emit light, and causes the voltage detector to detect the anode voltage by turning off the first switch and turning on the second switch while the organic EL element is emitting light.
    Type: Grant
    Filed: April 30, 2010
    Date of Patent: October 1, 2013
    Assignee: Panasonic Corporation
    Inventors: Hiroshi Shirouzu, Tetsurou Nakamura
  • Patent number: 8456389
    Abstract: A display device includes a luminescence element. A power line provides the luminescence element with an electric current. A capacitor accumulates a driving voltage corresponding to a data voltage. A driver flows the electric current according to the driving voltage accumulated in the capacitor through the luminescence element via the power line. A controller is configured to set a reverse bias voltage and an application time period according to an amount of luminescence produced by the luminescence element, and to determine luminance levels in luminescence periods. The controller sets the reverse bias voltage and the application time period according to a peak luminance of the luminance levels when a difference between the peak luminance and an average luminance of the luminance levels exceeds a predetermined threshold, and applies the reverse bias voltage for the application time period within an OFF period of the data voltage for removing an electric charge accumulated in the luminescence element.
    Type: Grant
    Filed: April 19, 2010
    Date of Patent: June 4, 2013
    Assignee: Panasonic Corporation
    Inventors: Kenichi Masumoto, Tetsurou Nakamura
  • Publication number: 20120327063
    Abstract: Display device includes: a power supplying unit which outputs at least a high-side or low-side output potential; an organic EL display unit which includes pixels and receives power supply from the power supplying unit; two or more detecting lines for transmitting a high-side or low-side applied potential applied to two or more pixels; a relay unit which outputs the high-side or low-side applied potentials transmitted by the detecting lines, to output lines fewer in number than the detecting lines; and a regulating unit which regulates at least the high-side or low-side output potential to be outputted by the power supplying unit, such that any one of potential difference between a reference potential and the high-side applied potential from the relay unit, potential difference between the reference potential and the low-side applied potential, and potential difference between the high-side applied potential and the low-side applied potential reaches a predetermined potential difference.
    Type: Application
    Filed: May 9, 2012
    Publication date: December 27, 2012
    Applicant: PANASONIC CORPORATION
    Inventors: Yosuke IZAWA, Toshiyuki KATO, Kouhei EBISUNO, Shinya ONO, Tetsurou NAKAMURA
  • Publication number: 20120154460
    Abstract: An organic electroluminescence display device includes a display panel including pixels. The pixels each include a light-emitter, driver and capacitor. A storage is configured to store a correction parameter for each of the pixels for correcting, in accordance with characteristics of each of the pixels, an image signal input from an external source. A controller is configured to, for each pixel of the pixels, obtain a corrected signal voltage by reading the correction parameter corresponding to the pixel from the storage and multiplying the image signal corresponding to the pixel by the correction parameter corresponding to the pixel. The storage is configured to store a gain and not an offset as the correction parameter.
    Type: Application
    Filed: February 23, 2012
    Publication date: June 21, 2012
    Applicant: PANASONIC CORPORATION
    Inventors: Yasuo SEGAWA, Tetsurou NAKAMURA, Shinya ONO
  • Publication number: 20120147070
    Abstract: A method of manufacturing an organic electroluminescence display includes preparing a substrate including pixels. The pixels each include a drive transistor and a capacitor. The capacitor of a subject pixel is caused to hold a voltage which corresponds to a threshold voltage of the drive transistor, and the voltage is read. A first signal voltage is obtained by adding a first correction parameter of the subject pixel to a second signal voltage corresponding to a single gradation level belonging to an intermediate gradation region or a high gradation region of representative voltage-luminance characteristics. The first signal voltage is applied to the driver of the subject pixel, and a luminance emitted by the subject pixel is measured. A second correction parameter with which the luminance emitted by the subject pixel becomes a standard luminance is calculated.
    Type: Application
    Filed: February 23, 2012
    Publication date: June 14, 2012
    Applicant: PANASONIC CORPORATION
    Inventors: Yasuo SEGAWA, Tetsurou NAKAMURA, Shinya ONO
  • Patent number: 8089477
    Abstract: A display device is provided which includes a luminescence element, a data line, and a switch connected between an electrode of the luminescence element and the data line. A voltage generation circuit supplies a pre-charge voltage to the data line. A current generation circuit supplies an inspection current to the electrode of the luminescence element plural times through the data line and the switch. A voltage detection circuit detects, the plural times, voltage values of the electrode supplied with the inspection current. When a difference between the voltage values is at least a predetermined value, the voltage generation circuit supplies the data line with an updated voltage that is higher than the pre-charge voltage.
    Type: Grant
    Filed: June 9, 2010
    Date of Patent: January 3, 2012
    Assignee: Panasonic Corporation
    Inventors: Hiroshi Shirouzu, Tetsurou Nakamura
  • Publication number: 20100245331
    Abstract: A display device is provided which includes a luminescence element, a data line, and a switch connected between an electrode of the luminescence element and the data line. A voltage generation circuit supplies a pre-charge voltage to the data line. A current generation circuit supplies an inspection current to the electrode of the luminescence element plural times through the data line and the switch. A voltage detection circuit detects, the plural times, voltage values of the electrode supplied with the inspection current. When a difference between the voltage values is at least a predetermined value, the voltage generation circuit supplies the data line with an updated voltage that is higher than the pre-charge voltage.
    Type: Application
    Filed: June 9, 2010
    Publication date: September 30, 2010
    Applicant: PANASONIC CORPORATION
    Inventors: Hiroshi SHIROUZU, Tetsurou NAKAMURA
  • Publication number: 20100214273
    Abstract: A display device includes an organic EL element and a capacitor. A driving transistor is connected to an anode of the organic EL element and passes a current to the organic EL element. The current corresponds to a voltage held in the capacitor. A first switch is between the capacitor and a data line, and the data line supplies the voltage to the capacitor. A voltage detector is connected to the data line for detecting an anode voltage applied to the organic EL element. A second switch is between the anode and the data line. A controller turns on the first switch, causes the organic EL element to emit light, and causes the voltage detector to detect the anode voltage by turning off the first switch and turning on the second switch while the organic EL element is emitting light.
    Type: Application
    Filed: April 30, 2010
    Publication date: August 26, 2010
    Applicant: PANASONIC CORPORATION
    Inventors: Hiroshi SHIROUZU, Tetsurou NAKAMURA
  • Publication number: 20100201722
    Abstract: A display device includes a luminescence element. A power line provides the luminescence element with an electric current. A capacitor accumulates a driving voltage corresponding to a data voltage. A driver flows the electric current according to the driving voltage accumulated in the capacitor through the luminescence element via the power line. A controller is configured to set a reverse bias voltage and an application time period according to an amount of luminescence produced by the luminescence element, and to determine luminance levels in luminescence periods. The controller sets the reverse bias voltage and the application time period according to a peak luminance of the luminance levels when a difference between the peak luminance and an average luminance of the luminance levels exceeds a predetermined threshold, and applies the reverse bias voltage for the application time period within an OFF period of the data voltage for removing an electric charge accumulated in the luminescence element.
    Type: Application
    Filed: April 19, 2010
    Publication date: August 12, 2010
    Applicant: PANASONIC CORPORATION
    Inventors: Kenichi MASUMOTO, Tetsurou NAKAMURA
  • Publication number: 20100182352
    Abstract: A display apparatus is provided which optimally restores decreased luminance and extends a life of a light emitting element. The display apparatus includes a memory that stores a plurality of trap levels in association with a plurality of use durations of the light emitting element. An obtainer determines one of the plurality of use durations of the light emitting element. A controller reads, from the memory, one of the plurality of trap levels associated with the one of the plurality of use durations, and removes a charge from the light emitting element by application of a reverse bias voltage having a level associated with the one of the plurality of trap levels. The controller changes the level of the reverse bias voltage which is applied to the light emitting element so that as the one of the plurality of use durations increases, the level of the reverse bias voltage increases.
    Type: Application
    Filed: March 29, 2010
    Publication date: July 22, 2010
    Applicant: PANASONIC CORPORATION
    Inventors: Tetsurou NAKAMURA, Kenichi MASUMOTO
  • Publication number: 20090316230
    Abstract: An exposure apparatus for an image forming apparatus is provided, the exposure apparatus being downsized by reducing the substrate on which a row of light emitting elements are provided in size in the sub-scanning direction. The exposure apparatus comprises a glass substrate, a row of light emitting elements constituted by multiple organic EL elements on the glass substrate, and a drive control unit for receiving from outside the glass substrate control signals for driving the organic EL elements and controlling the drive of the light emitting elements based on the control signals, wherein the drive control unit is at least partly placed on the extended line of the row of light emitting elements.
    Type: Application
    Filed: May 25, 2006
    Publication date: December 24, 2009
    Applicant: MATSUSHITA ELECTRIC INDUSTRIAL CO., LTD.
    Inventors: Tetsurou Nakamura, Yuuji Toyomura
  • Publication number: 20090251675
    Abstract: In an exposure device having tiny light emitting elements aligned, a space required for drive circuits and wires is secured without affecting the size or alignment of the light emitting elements for arrangement and wiring of the drive circuits. In this exposure device, the drive circuits are separately arranged outside the column formed by the multiple organic EL elements, and, the length of the region occupied by the circuit exceeds one pitch in the alignment of the organic EL elements, and, the multiple drive circuits are arranged along the column.
    Type: Application
    Filed: July 13, 2006
    Publication date: October 8, 2009
    Applicant: MATSUSHITA ELECTRIC INDUSTRIAL CO., LTD.
    Inventors: Kenichi Masumoto, Tetsurou Nakamura, Kei Sakanoue
  • Patent number: 7504616
    Abstract: To provide an exposure device and an image forming apparatus using the same, in which the exposure device can detect light intensity with improved reliability and thereby controls the light intensity with high precision, the exposure device includes an EL (electro-luminescence) element having a first electrode (an anode), a second electrode (a cathode), and a light emitting layer disposed between the first and second electrodes, thereby forming a light emitting unit, and a light detecting element detecting light emitted from the EL element, in which the EL element and the light detecting element are stacked onto each other. The light detecting element is provided at an inner side of a principal surface of the electrode (the anode) which is disposed closer to the light detecting element than the other electrode. A light emitting area of the EL element is provided at an inner side of a principal surface of the light detecting element.
    Type: Grant
    Filed: April 6, 2007
    Date of Patent: March 17, 2009
    Assignee: Panasonic Corporation
    Inventors: Tetsurou Nakamura, Hiroshi Shirouzu, Takafumi Hamano, Shinya Yamamoto