Patents by Inventor Akira Nagumo

Akira Nagumo 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).

  • Publication number: 20190035971
    Abstract: One of embodiments is a method of manufacturing driven element chips by dividing a semiconductor wafer into the driven element chips. The method includes preparing a semiconductor wafer which includes chip substrate portions arrayed in an array direction, and a clearance between the chip substrate portions adjacent to each other in the array direction. Each chip substrate portion includes: a conductive layer provided inside the chip substrate portion and including interconnect portions; and a dummy conductor provided in a part of the conductive layer where the interconnect portions are not provided.
    Type: Application
    Filed: July 19, 2018
    Publication date: January 31, 2019
    Applicant: Oki Data Corporation
    Inventors: Akira NAGUMO, Shinya JUMONJI, Minoru FUJITA
  • Patent number: 9826588
    Abstract: Provided is a light-emission drive circuit that includes a power supply and a pull-up circuit. The power supply is configured to generate a voltage that is higher than a voltage in a controller. The controller is configured to supply a control signal that drives a light-emitting section. The pull-up circuit is provided between the power supply and an input terminal of the light-emission drive circuit, and includes a switching section configured to be turned on when a voltage of the input terminal is lower than a predetermined voltage. The predetermined voltage is lower than the voltage of the power supply.
    Type: Grant
    Filed: February 22, 2016
    Date of Patent: November 21, 2017
    Assignee: Oki Data Corporation
    Inventor: Akira Nagumo
  • Publication number: 20160295651
    Abstract: Provided is a light-emission drive circuit that includes a power supply and a pull-up circuit. The power supply is configured to generate a voltage that is higher than a voltage in a controller. The controller is configured to supply a control signal that drives a light-emitting section. The pull-up circuit is provided between the power supply and an input terminal of the light-emission drive circuit, and includes a switching section configured to be turned on when a voltage of the input terminal is lower than a predetermined voltage. The predetermined voltage is lower than the voltage of the power supply.
    Type: Application
    Filed: February 22, 2016
    Publication date: October 6, 2016
    Applicant: Oki Data Corporation
    Inventor: Akira NAGUMO
  • Patent number: 9090094
    Abstract: A driving circuit includes a reference voltage generating circuit and a driver circuit. The driver circuit drives a driven element at a level determined by the reference voltage output by the reference voltage generating circuit. The reference voltage generating circuit includes a regulating section that generates a regulated voltage, a temperature compensation section that applies a temperature compensation to the regulated voltage to compensate for the temperature characteristics of the driven element, and a voltage amplifying section that amplifies the resulting temperature compensated voltage to generate the reference voltage, thereby supplying a reference voltage high enough to avoid noise effects.
    Type: Grant
    Filed: February 7, 2011
    Date of Patent: July 28, 2015
    Assignee: Oki Data Corporation
    Inventor: Akira Nagumo
  • Patent number: 9048841
    Abstract: A driver circuit drives a plurality of groups of light emitting elements. Each element includes an anode, a cathode connected to the ground, and a gate that controls electrical conduction between the anode and cathode. A first driver section simultaneously drives the anodes of the elements of the plurality of groups of elements. A second driver section simultaneously drives the gates of the elements in a corresponding group of the plurality of groups. The second driver section includes a series connection of a first switch element and a voltage level shifter. The series connection is connected between a power supply and the group of gates. The second driver section further includes a second switch element connected between the group of gates and the ground.
    Type: Grant
    Filed: December 3, 2010
    Date of Patent: June 2, 2015
    Assignee: Oki Data Corporation
    Inventor: Akira Nagumo
  • Patent number: 8884555
    Abstract: A light-emitting element array has a plurality of three-terminal light-emitting elements such as light-emitting thyristors with anode, cathode, and gate terminals. The anode terminal of each light-emitting element is connected to a driving circuit. The cathode terminal is grounded. The gate terminals of at least some of the three-terminal light-emitting elements are driven from a common buffer, and within this group of three-terminal light-emitting elements, the anode terminals are driven individually. This enables the array of three-terminal light-emitting elements to be driven in essentially the same way as an array of two-terminal light-emitting elements, but without the need for large power transistors between the cathode terminals and ground.
    Type: Grant
    Filed: August 9, 2012
    Date of Patent: November 11, 2014
    Assignee: Oki Data Corporation
    Inventor: Akira Nagumo
  • Patent number: 8866866
    Abstract: A drive circuit is provided for supplying a drive current to drive a plurality of driven elements. The drive circuit includes a switch circuit having an input terminal for receiving a drive signal alternately changing between an on state and an off state, and an output terminal connected to the driven elements; and a constant current circuit connected to the switch circuit for adjusting the drive current at a constant level. The constant current circuit is formed of a depletion type MOS transistor.
    Type: Grant
    Filed: August 1, 2013
    Date of Patent: October 21, 2014
    Assignee: Oki Data Corporation
    Inventor: Akira Nagumo
  • Patent number: 8848012
    Abstract: A drive device to drive a plurality of three-terminal light emitting elements, comprising: a drive circuit including a first MOS transistor and configured to drive conducting three-terminal light emitting elements among a plurality of three-terminal light emitting elements based on a received drive signal. The first MOS transistor includes: a third terminal connected to a second power supply having a potential different from a potential of the first power supply; a fourth terminal connected to the second terminals connected in common, a second control terminal configured to control a conduction state between the third terminal and the fourth terminal based on the drive signal; and a substrate terminal set to have a potential different from the potential of the second power supply in a direction of increasing threshold voltage of the first MOS transistor.
    Type: Grant
    Filed: March 23, 2011
    Date of Patent: September 30, 2014
    Assignee: Oki Data Corporation
    Inventor: Akira Nagumo
  • Patent number: 8835974
    Abstract: A driving device that drives a light emitting thyristor array includes: a first driving circuit operated by a second power source; a scanning circuit including plural stages of scanning thyristors and sequentially scanning the plural stages of light emitting thyristors, a second driving circuit operated by a second power source, generating first and second clock signals for driving the scanning circuit, and outputting the first and second clock signals from first and second clock terminals, respectively, a terminal of an odd numbered stage scanning thyristor is commonly connected to the first clock terminal, another terminal of an even numbered stage scanning thyristor is commonly connected to the second clock terminal, and a control terminal of a first stage scanning thyristor is connected to the second clock terminal via a first resistor.
    Type: Grant
    Filed: June 22, 2011
    Date of Patent: September 16, 2014
    Assignee: Oki Data Corporation
    Inventor: Akira Nagumo
  • Patent number: 8836743
    Abstract: A drive device to drive a plurality of three-terminal light emitting elements includes a drive circuit. The drive circuit includes a first and second conductive type MOS transistor complementarily connected to each other and configured to drive three-terminal light emitting elements that are in conduction state based on a received drive signal. The first conductive type MOS transistor is formed in a substrate region and includes a channel formation region, which is a region wherein a channel is to be formed. An impurity with the same polarity as that of the substrate region is injected in the channel formation region.
    Type: Grant
    Filed: March 23, 2011
    Date of Patent: September 16, 2014
    Assignee: Oki Data Corporation
    Inventor: Akira Nagumo
  • Patent number: 8742824
    Abstract: A driver circuit is used for driving a plurality of switch elements connected between a power supply terminal and a common terminal. Each switch element includes an anode connected to the power supply terminal, a cathode, and a gate. The cathode is connected to a common terminal. The gate controls electrical conduction between the anode and the cathode. The driver circuit includes a switch circuit connected between the power supply terminal and the common terminal, and a driver into which a drive current flows. The switch circuit is in parallel with the switch elements, and electrically connects or disconnects the power supply terminal and the common terminal in response to a control signal supplied thereto. A transmission line, having a specific characteristic impedance, is connected between the common terminal and the driver circuit.
    Type: Grant
    Filed: January 20, 2011
    Date of Patent: June 3, 2014
    Assignee: Oki Data Corporation
    Inventor: Akira Nagumo
  • Patent number: 8723903
    Abstract: A drive device for outputting a drive signal for driving a plurality of light emitting elements time-divisionally, the drive device includes a plurality of input terminals receiving input of a drive control signal for the light emitting elements, and a plurality of output terminals connected to the light emitting elements, for outputting the drive signal based on the drive control signal input into the input terminals, in which the input terminals and the output terminals are arranged substantially in a line.
    Type: Grant
    Filed: March 6, 2012
    Date of Patent: May 13, 2014
    Assignee: Oki Data Corporation
    Inventor: Akira Nagumo
  • Patent number: 8704862
    Abstract: A method of manufacturing a semiconductor composite device, including steps of: preparing a substrate comprising circuit elements, which are part of a driving circuit; attaching an array of driven elements onto the substrate via a passivation layer, the array being formed of a semiconductor thin film having a crystal structure wherein the driven elements are arrayed to be driven by the driving circuit; and forming a metal wire by a photo-lithography method such that the circuit elements are electrically connected with the metal wire to form the driving circuit and the driving circuit is electrically connected to the driven elements with the metal wire.
    Type: Grant
    Filed: September 1, 2010
    Date of Patent: April 22, 2014
    Assignee: Oki Data Corporation
    Inventor: Akira Nagumo
  • Patent number: 8698864
    Abstract: A driver apparatus drives aligned light emitting thyristors. Each thyristor includes an anode, a cathode, and a gate. The driver apparatus includes a common terminal, a first resistor, a second resistor, and a switch. Each thyristor is disposed at a first position where the anode is connected to the first potential and the cathode is connected to the common terminal, or a second position where the anode is connected to the common terminal and the cathode is connected to the second potential. The first resistor is connected between the first potential and the common terminal. The second resistor is connected between the common terminal and the second potential. The switch is connected at a third position where the switch is connected between the between the first potential and the common terminal, or a fourth position where the switch is connected between the common terminal and the second potential.
    Type: Grant
    Filed: March 29, 2012
    Date of Patent: April 15, 2014
    Assignee: Oki Data Corporation
    Inventor: Akira Nagumo
  • Patent number: 8614728
    Abstract: A driver device scans and drives light emission elements arranged in a branch connection to a common terminal using scan-circuit and data drive portions and clock driver and waveform shaper circuits. The scan circuit portion has scan circuits connected cascadely to one another with output terminals connected to the light emission elements. The driver device outputs first and second clock signals to odd- and even-numbered scan circuits respectively. The light emission elements are sequentially driven from a first to a last scan circuit when the second-clock signal is applied to the first scan circuit. The data-drive portion drives the common terminal. The clock-driver circuit outputs first and second clock pulses with different phases, and a third-clock pulse synchronized with the first and second clock pulses. The waveform-shaper circuit re-shapes the waveforms of the clock signals.
    Type: Grant
    Filed: March 29, 2012
    Date of Patent: December 24, 2013
    Assignee: Oki Data Corporation
    Inventor: Akira Nagumo
  • Publication number: 20130315613
    Abstract: A drive circuit is provided for supplying a drive current to drive a plurality of driven elements. The drive circuit includes a switch circuit having an input terminal for receiving a drive signal alternately changing between an on state and an off state, and an output terminal connected to the driven elements; and a constant current circuit connected to the switch circuit for adjusting the drive current at a constant level. The constant current circuit is formed of a depletion type MOS transistor.
    Type: Application
    Filed: August 1, 2013
    Publication date: November 28, 2013
    Applicant: OKI DATA CORPORATION
    Inventor: Akira NAGUMO
  • Patent number: 8587628
    Abstract: A driver apparatus drives light emitting elements connected to a common terminal. A clock driver outputs first and second pulses to first and second output terminals, respectively, alternately. A differentiating circuit includes an inductor and a resistor, and differentiates the first and second pulses to produce first and second clocks, respectively. A data driver circuit outputs a data signal to the common terminal in response to an ON/OFF command signal. A scanning circuit starts to operate in response to a starting signal such that the cascaded sub scanning stages turn on in sequence one at a time. A sub scanning stage turns on in response to the second clock, outputting a drive signal to a corresponding one of the light emitting elements. The light emitting elements emit light only when the drive signal and the ON/OFF command signal are fed to the light emitting elements.
    Type: Grant
    Filed: August 26, 2011
    Date of Patent: November 19, 2013
    Assignee: Oki Data Corporation
    Inventor: Akira Nagumo
  • Patent number: 8581946
    Abstract: When the cathode of a light emitting thyristor is at the low (L) level, voltage is applied between the anode and cathode of the light emitting thyristor. In addition, because the gate of each thyristor and the gate of each light emitting thyristor are connected to each other in a self scanning circuit 100, voltage is also applied between the gate and cathode of the thyristor. At this time, by selectively turning only the gate of the light emitting thyristor, which is instructed by the self scanning circuit to emit light, to the high (H) level, the light emitting thyristor that is instructed is turned on. In particular, because an output signal of a clock driving circuit is differentiated by an RL differential circuit to generate an undershoot or overshoot waveform, the number of output terminals of the clock driving circuit can be reduced.
    Type: Grant
    Filed: March 24, 2011
    Date of Patent: November 12, 2013
    Assignee: Oki Data Corporation
    Inventor: Akira Nagumo
  • Patent number: 8542262
    Abstract: A light emitting element array includes a plurality of light emitting elements each having a first terminal, a second terminal, and a third terminal. The light emitting elements are arranged next to each other to form a group. The first terminal receives a drive signal, the second terminal is connected to ground, and the third terminal has a threshold voltage or a threshold current controllable from outside so that the light emitting elements are driven in a time division way.
    Type: Grant
    Filed: November 10, 2009
    Date of Patent: September 24, 2013
    Assignee: Oki Data Corporation
    Inventor: Akira Nagumo
  • Patent number: 8525861
    Abstract: A drive circuit is provided for supplying a drive current to drive a plurality of driven elements each having two main electrodes. The drive circuit includes a switch circuit for receiving a drive signal; and a constant current circuit connected to the switch circuit for adjusting the drive current at a constant level. The constant current circuit is formed of a depletion type MOS transistor.
    Type: Grant
    Filed: June 9, 2011
    Date of Patent: September 3, 2013
    Assignee: Oki Data Corporation
    Inventor: Akira Nagumo