Patents by Inventor NAOKO GOTOH

NAOKO GOTOH 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: 10614757
    Abstract: An organic EL panel 10 is a bendable display panel including a plurality of pixel circuits 60 each having a light emitting element and a drive element. A data line drive circuit 15 performs, by driving data lines, an operation of writing a voltage to a control terminal of the drive element and an operation of measuring a current flowing through the drive element for the pixel circuits 60 selected by a scanning line drive circuit 14. A bending detection unit 90 detects a bending state of the organic EL panel 10 based on a measurement result of the current flowing through the drive element. A correction unit 80 corrects a video signal VS1 based on the detected bending state. With this, the bending state of a screen is detected and a change in brightness or color when the screen is bent is prevented.
    Type: Grant
    Filed: November 25, 2016
    Date of Patent: April 7, 2020
    Assignee: SHARP KABUSHIKI KAISHA
    Inventors: Kazuo Takizawa, Noritaka Kishi, Naoko Gotoh, Hideki Uchida, Katsuhiro Kikuchi
  • Patent number: 10510285
    Abstract: A measurement circuit includes a plurality of measurement units, performs, at a same timing, a main measurement for measuring a current or a voltage with respect to a pixel circuit with supplying a measurement voltage to a part of the measurement units and a dummy measurement for measuring a current or a voltage with supplying a dummy signal to remaining measurement units, and performs a calculation on a result of the main measurement and a result of the dummy measurement. As the dummy signal, a signal with which a value to be measured is approximately zero is used. The measurement result of the current or the voltage is used for correcting a video signal. With this, a display device which can remove noise in measurement when measuring the current or the voltage with respect to the pixel circuit is provided.
    Type: Grant
    Filed: January 27, 2016
    Date of Patent: December 17, 2019
    Assignee: SHARP KABUSHIKI KAISHA
    Inventors: Noritaka Kishi, Hiroyuki Furukawa, Katsuya Otoi, Kazuyoshi Yoshiyama, Tamotsu Sakai, Naoko Gotoh
  • Patent number: 10319305
    Abstract: A current measurement circuit measures a current flowing through a drive transistor when a plurality of measurement voltages are written to a pixel circuit in a switching manner, and a current flowing through an organic EL element when another plurality of measurement voltages are written to the pixel circuit in a switching manner. A correction unit obtains a threshold voltage and a gain of the drive transistor and the organic EL element with respect to each pixel circuit based on a measured current, determines in which operation region the drive transistor operates between a saturation region and a triode region with respect to each pixel circuit based on the video signal, and corrects the video signal in accordance with the operation region of the drive transistor. Since the drive transistor operates both in the saturation region and the triode region, it is possible to reduce a power supply voltage and reduce power consumption of a display device.
    Type: Grant
    Filed: February 3, 2016
    Date of Patent: June 11, 2019
    Assignee: SHARP KABUSHIKI KAISHA
    Inventors: Noritaka Kishi, Hiroyuki Furukawa, Katsuya Otoi, Kazuyoshi Yoshiyama, Tamotsu Sakai, Naoko Gotoh
  • Patent number: 10269301
    Abstract: In a current measurement period of a pixel circuit (20), a measurement voltage is applied to a non-inverting input terminal of an operational amplifier (31), switches (35, 36) turn on, and a switch (37) turns off. Next, the switch (36) turns off, and a capacitor (32) is charged with charge of a current flowing through the pixel circuit (20). Next, the switch (35) turns off, the switch (37) turns on, a constant current flows through a current source (33), and a voltage of a second terminal (terminal connected to an output terminal of the operational amplifier (31)) of the capacitor (32) decreases. A voltage comparator (42) and a counter (43) measure the current flowing through the pixel circuit (20) by measuring time until a voltage of the second terminal of the capacitor reaches a voltage Vcomp. A video signal VS1 is corrected based on a current measurement result.
    Type: Grant
    Filed: March 18, 2016
    Date of Patent: April 23, 2019
    Assignee: SHARP KABUSHIKI KAISHA
    Inventors: Noritaka Kishi, Hiroyuki Furukawa, Katsuya Otoi, Kazuyoshi Yoshiyama, Tamotsu Sakai, Naoko Gotoh
  • Publication number: 20190057649
    Abstract: An organic EL panel 10 is a bendable display panel including a plurality of pixel circuits 60 each having a light emitting element and a drive element. A data line drive circuit 15 performs, by driving data lines, an operation of writing a voltage to a control terminal of the drive element and an operation of measuring a current flowing through the drive element for the pixel circuits 60 selected by a scanning line drive circuit 14. A bending detection unit 90 detects a bending state of the organic EL panel 10 based on a measurement result of the current flowing through the drive element. A correction unit 80 corrects a video signal VS1 based on the detected bending state. With this, the bending state of a screen is detected and a change in brightness or color when the screen is bent is prevented.
    Type: Application
    Filed: November 25, 2016
    Publication date: February 21, 2019
    Inventors: Kazuo TAKIZAWA, Noritaka KISHI, Naoko GOTOH, Hideki UCHIDA, Katsuhiro KIKUCHI
  • Publication number: 20180061328
    Abstract: In a current measurement period of a pixel circuit (20), a measurement voltage is applied to a non-inverting input terminal of an operational amplifier (31), switches (35, 36) turn on, and a switch (37) turns off. Next, the switch (36) turns off, and a capacitor (32) is charged with charge of a current flowing through the pixel circuit (20). Next, the switch (35) turns off, the switch (37) turns on, a constant current flows through a current source (33), and a voltage of a second terminal (terminal connected to an output terminal of the operational amplifier (31)) of the capacitor (32) decreases. A voltage comparator (42) and a counter (43) measure the current flowing through the pixel circuit (20) by measuring time until a voltage of the second terminal of the capacitor reaches a voltage Vcomp. A video signal VS1 is corrected based on a current measurement result.
    Type: Application
    Filed: March 18, 2016
    Publication date: March 1, 2018
    Inventors: Noritaka KISHI, Hiroyuki FURUKAWA, Katsuya OTOI, Kazuyoshi YOSHIYAMA, Tamotsu SAKAI, Naoko GOTOH
  • Publication number: 20180033372
    Abstract: A current measurement circuit measures a current flowing through a drive transistor when a plurality of measurement voltages are written to a pixel circuit in a switching manner, and a current flowing through an organic EL element when another plurality of measurement voltages are written to the pixel circuit in a switching manner. A correction unit obtains a threshold voltage and a gain of the drive transistor and the organic EL element with respect to each pixel circuit based on a measured current, determines in which operation region the drive transistor operates between a saturation region and a triode region with respect to each pixel circuit based on the video signal, and corrects the video signal in accordance with the operation region of the drive transistor. Since the drive transistor operates both in the saturation region and the triode region, it is possible to reduce a power supply voltage and reduce power consumption of a display device.
    Type: Application
    Filed: February 3, 2016
    Publication date: February 1, 2018
    Applicant: SHARP KABUSHIKI KAISHA
    Inventors: NORITAKA KISHI, HIROYUKI FURUKAWA, KATSUYA OTOI, KAZUYOSHI YOSHIYAMA, TAMOTSU SAKAI, NAOKO GOTOH
  • Publication number: 20170365205
    Abstract: A measurement circuit includes a plurality of measurement units, performs, at a same timing, a main measurement for measuring a current or a voltage with respect to a pixel circuit with supplying a measurement voltage to a part of the measurement units and a dummy measurement for measuring a current or a voltage with supplying a dummy signal to remaining measurement units, and performs a calculation on a result of the main measurement and a result of the dummy measurement. As the dummy signal, a signal with which a value to be measured is approximately zero is used. The measurement result of the current or the voltage is used for correcting a video signal. With this, a display device which can remove noise in measurement when measuring the current or the voltage with respect to the pixel circuit is provided.
    Type: Application
    Filed: January 27, 2016
    Publication date: December 21, 2017
    Inventors: NORITAKA KISHI, HIROYUKI FURUKAWA, KATSUYA OTOI, KAZUYOSHI YOSHIYAMA, TAMOTSU SAKAI, NAOKO GOTOH