Patents by Inventor Yuuki OKA

Yuuki OKA 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: 11899107
    Abstract: A detection apparatus includes a light source device, including a plurality of light-emitting elements, configured to irradiate light onto a detection target by dividing an illuminance area into a plurality of illuminance regions; and circuitry configured to switch an illuminance level at each of the plurality of illuminance regions with a plurality of illuminance levels; detect a plurality of detection data of the detection target at the plurality of illuminance regions by switching the illuminance level at each of the plurality of illuminance regions with the plurality of illuminance levels when irradiating the light onto the detection target; and synthesize the plurality of detection data of the detection target.
    Type: Grant
    Filed: October 22, 2020
    Date of Patent: February 13, 2024
    Assignee: RICOH COMPANY, LTD.
    Inventors: Takumi Satoh, Yuuki Oka
  • Patent number: 11563304
    Abstract: A lighting module includes a voltage-current controller to control power externally supplied, a capacitor charged with power supplied from the voltage-current controller, a laser light source to emit laser light driven by a current from the capacitor, first and second FETs electrically connected in series to the laser light source, and circuitry that controls a first voltage value applied to the first FET and a second voltage value applied to the second FET, to control a resistance value of the second FET. The first FET controls a pulse width of the current flowing through the laser light source in accordance with the first voltage value applied to a gate thereof. The second FET changes in resistance value in accordance with the second voltage value applied to a gate thereof and controls, with the resistance value, a peak value of the current flowing through the laser light source.
    Type: Grant
    Filed: July 12, 2021
    Date of Patent: January 24, 2023
    Assignee: Ricoh Company, Ltd.
    Inventors: Yuuki Oka, Takumi Satoh, Tsuyoshi Ueno, Atsufumi Omori
  • Publication number: 20220299607
    Abstract: A light source module, a distance-measuring apparatus, and a mobile object. The light source module includes a first substrate, a light source disposed on the first substrate to emit light, the light source having a first terminal and a second terminal, a field-effect transistor disposed on the first substrate, the field-effect transistor having a third terminal and a fourth terminal, and a charge storage unit disposed on the first substrate, the charge storage unit having a fifth terminal and a sixth terminal. In the light source module, the first terminal and the sixth terminal are coupled to each other, the second terminal and the third terminal are coupled to each other. In the light source module, the fourth terminal and the fifth terminal are at an equivalent electrical potential. The distance-measuring apparatus includes the light source module. The includes the distance-measuring apparatus.
    Type: Application
    Filed: March 7, 2022
    Publication date: September 22, 2022
    Inventors: Yuuki OKA, Kazuma IZUMIYA, Takumi SATOH
  • Patent number: 11363694
    Abstract: A drive circuit 3 includes a power source 11; current control units 12-1 to 12-n configured to control the amount of currents supplied to a light emitting element in accordance with a pulse modulation signal; and a calculation unit 13 configured to change a duty ratio of a pulse modulation signal. The current control units 12-1 to 12-n include a first switching element 21 configured to be switched on/off in accordance with a pulse modulation signal; and a second switching element 22 configured to be switched on/off in accordance with an inversion signal of the pulse modulation signal input to the first switching element 21; and an inductor 23. The first switching element 21 and the inductor 23 are serially connected between the power source and the light emitting element. The second switching element 22 is connected between ground 25 and a contact point 24 of the first switching element 21 and the inductor 23. The two or more current control units 12-1 to 12-n are connected in parallel.
    Type: Grant
    Filed: July 28, 2021
    Date of Patent: June 14, 2022
    Assignees: RICOH COMPANY, LTD., KYUSHU INSTITUTE OF TECHNOLOGY
    Inventors: Tsuyoshi Ueno, Yuuki Oka, Tetsuya Satoh, Seiya Abe
  • Publication number: 20220137188
    Abstract: An optical element includes a first surface; and a second surface facing the first surface; a light-transmissive portion to transmit and diverge a light beam incident on the light-transmissive portion from outside of the first surface to emit a diverging light beam to outside of the second surface; and a light-deflecting portion to deflect a light beam incident on the first surface from the outside of the first surface, in a direction different from a direction of specular reflection on the first surface outside the first surface.
    Type: Application
    Filed: October 28, 2021
    Publication date: May 5, 2022
    Inventors: Takumi SATOH, Yuuki OKA
  • Publication number: 20220037853
    Abstract: A lighting module includes a voltage-current controller to control power externally supplied, a capacitor charged with power supplied from the voltage-current controller, a laser light source to emit laser light driven by a current from the capacitor, first and second FETs electrically connected in series to the laser light source, and circuitry that controls a first voltage value applied to the first FET and a second voltage value applied to the second FET, to control a resistance value of the second FET. The first FET controls a pulse width of the current flowing through the laser light source in accordance with the first voltage value applied to a gate thereof. The second FET changes in resistance value in accordance with the second voltage value applied to a gate thereof and controls, with the resistance value, a peak value of the current flowing through the laser light source.
    Type: Application
    Filed: July 12, 2021
    Publication date: February 3, 2022
    Applicant: Ricoh Company, Ltd.
    Inventors: Yuuki Oka, Takumi Satoh, Tsuyoshi Ueno, Atsufumi Omori
  • Patent number: 11240894
    Abstract: A drive circuit includes a plurality of capacitors; a plurality of first interrupters configured to select paths through which electric charges are supplied to the plurality of capacitors; and a plurality of second interrupters configured to select paths through which the plurality of capacitors supply electric charges to a plurality of light emitting elements. In a case where the first interrupters are controlled and an electric charge is stored in a capacitor corresponding to one light emitting element included in the plurality of light emitting elements to selectively turn on the one light emitting element, at least while an electric charge is supplied to a light emitting element to be turned on, one second interrupter coupled to a path through which an electric charge is supplied to a light emitting element not to be turned on interrupts the path.
    Type: Grant
    Filed: November 19, 2019
    Date of Patent: February 1, 2022
    Assignee: RICOH COMPANY, LTD.
    Inventor: Yuuki Oka
  • Publication number: 20210360758
    Abstract: A drive circuit 3 includes a power source 11; current control units 12-1 to 12-n configured to control the amount of currents supplied to a light emitting element in accordance with a pulse modulation signal; and a calculation unit 13 configured to change a duty ratio of a pulse modulation signal. The current control units 12-1 to 12-n include a first switching element 21 configured to be switched on/off in accordance with a pulse modulation signal; and a second switching element 22 configured to be switched on/off in accordance with an inversion signal of the pulse modulation signal input to the first switching element 21; and an inductor 23. The first switching element 21 and the inductor 23 are serially connected between the power source and the light emitting element. The second switching element 22 is connected between ground 25 and a contact point 24 of the first switching element 21 and the inductor 23. The two or more current control units 12-1 to 12-n are connected in parallel.
    Type: Application
    Filed: July 28, 2021
    Publication date: November 18, 2021
    Applicants: Ricoh Company, Ltd., Kyushu Institute of Technology
    Inventors: Tsuyoshi UENO, Yuuki OKA, Tetsuya SATOH, Seiya ABE
  • Patent number: 11109459
    Abstract: A drive circuit 3 includes a power source 11; current control units 12-1 to 12-n configured to control the amount of currents supplied to a light emitting element in accordance with a pulse modulation signal; and a calculation unit 13 configured to change a duty ratio of a pulse modulation signal. The current control units 12-1 to 12-n include a first switching element 21 configured to be switched on/off in accordance with a pulse modulation signal; and a second switching element 22 configured to be switched on/off in accordance with an inversion signal of the pulse modulation signal input to the first switching element 21; and an inductor 23. The first switching element 21 and the inductor 23 are serially connected between the power source and the light emitting element. The second switching element 22 is connected between ground 25 and a contact point 24 of the first switching element 21 and the inductor 23. The two or more current control units 12-1 to 12-n are connected in parallel.
    Type: Grant
    Filed: May 23, 2018
    Date of Patent: August 31, 2021
    Assignees: RICOH COMPANY, LTD., KYUSHU INSTITUTE OF TECHNOLOGY
    Inventors: Tsuyoshi Ueno, Yuuki Oka, Tetsuya Satoh, Seiya Abe
  • Publication number: 20210124046
    Abstract: A detection apparatus includes a light source device, including a plurality of light-emitting elements, configured to irradiate light onto a detection target by dividing an illuminance area into a plurality of illuminance regions; and circuitry configured to switch an illuminance level at each of the plurality of illuminance regions with a plurality of illuminance levels; detect a plurality of detection data of the detection target at the plurality of illuminance regions by switching the illuminance level at each of the plurality of illuminance regions with the plurality of illuminance levels when irradiating the light onto the detection target; and synthesize the plurality of detection data of the detection target.
    Type: Application
    Filed: October 22, 2020
    Publication date: April 29, 2021
    Inventors: Takumi SATOH, Yuuki OKA
  • Publication number: 20200178361
    Abstract: A drive circuit includes a plurality of capacitors; a plurality of first interrupters configured to select paths through which electric charges are supplied to the plurality of capacitors; and a plurality of second interrupters configured to select paths through which the plurality of capacitors supply electric charges to a plurality of light emitting elements. In a case where the first interrupters are controlled and an electric charge is stored in a capacitor corresponding to one light emitting element included in the plurality of light emitting elements to selectively turn on the one light emitting element, at least while an electric charge is supplied to a light emitting element to be turned on, one second interrupter coupled to a path through which an electric charge is supplied to a light emitting element not to be turned on interrupts the path.
    Type: Application
    Filed: November 19, 2019
    Publication date: June 4, 2020
    Inventor: Yuuki Oka
  • Publication number: 20200160777
    Abstract: A drive circuit 3 includes a power source 11; current control units 12-1 to 12-n configured to control the amount of currents supplied to a light emitting element in accordance with a pulse modulation signal; and a calculation unit 13 configured to change a duty ratio of a pulse modulation signal. The current control units 12-1 to 12-n include a first switching element 21 configured to be switched on/off in accordance with a pulse modulation signal; and a second switching element 22 configured to be switched on/off in accordance with an inversion signal of the pulse modulation signal input to the first switching element 21; and an inductor 23. The first switching element 21 and the inductor 23 are serially connected between the power source and the light emitting element. The second switching element 22 is connected between ground 25 and a contact point 24 of the first switching element 21 and the inductor 23. The two or more current control units 12-1 to 12-n are connected in parallel.
    Type: Application
    Filed: May 23, 2018
    Publication date: May 21, 2020
    Applicants: Ricoh Company, Ltd., Kyushu Institute of Technology
    Inventors: Tsuyoshi UENO, Yuuki OKA, Tetsuya SATOH, Seiya ABE
  • Patent number: 10530123
    Abstract: A drive circuit is configured to supply a current to a light emitting element. The drive circuit includes a plurality of switching elements configured to switch between ON/OFF states with a modulation signal, a capacitor connected in parallel with the light emitting element, and a control module configured to control the switching elements so that a voltage of the capacitor does not become lower than a threshold.
    Type: Grant
    Filed: March 12, 2018
    Date of Patent: January 7, 2020
    Assignee: RICOH COMPANY, LTD.
    Inventors: Yuuki Oka, Tsuyoshi Ueno, Seiya Abe
  • Publication number: 20180269651
    Abstract: A drive circuit is configured to supply a current to a light emitting element. The drive circuit includes a plurality of switching elements configured to switch between ON/OFF states with a modulation signal, a capacitor connected in parallel with the light emitting element, and a control module configured to control the switching elements so that a voltage of the capacitor does not become lower than a threshold.
    Type: Application
    Filed: March 12, 2018
    Publication date: September 20, 2018
    Applicants: Ricoh Company, Ltd., Kyushu Institute of Technology
    Inventors: Yuuki OKA, Tsuyoshi UENO, Seiya ABE
  • Patent number: 9964904
    Abstract: A fixing device includes a fixing member, which includes heat-generating layer, and an induction heater to inductively heat the fixing member. The induction heater includes an excitation coil disposed facing an outer circumferential surface of the fixing member to generate a magnetic flux, a ferromagnetic core assembly containing a ferromagnetic core to form a magnetic path to direct the magnetic flux generated by the excitation coil to the fixing member, and a holder to hold the excitation coil and the ferromagnetic core assembly. The ferromagnetic core is insert-molded in and covered by the holder. The holder has a plurality of spherical marks created by a plurality of stabilizing members each having a spherical tip to stabilize the ferromagnetic core in a mold.
    Type: Grant
    Filed: March 26, 2014
    Date of Patent: May 8, 2018
    Assignee: Ricoh Company, Ltd.
    Inventors: Yuuki Oka, Yukari Isoe, Motokazu Hasegawa
  • Patent number: 9745403
    Abstract: To provide a polymer material having properties that allow the polymer material to replace a polyimide and a polyamide synthesized from a petroleum raw material, said polymer material being synthesized from a raw material derived from natural molecules. [Solution] This polymer material is obtained by polymerizing a polymer raw material comprising a dimer of 4-amino cinnamic acid or a dimer of a 4-amino cinnamic acid derivative, which are natural molecules, wherein the carboxyl group is protected by an alkyl chain. The TGA curve of a polyamide acid (PAA-1) and a polyimide (PI-1) according to the present invention is shown in FIG. 5.
    Type: Grant
    Filed: November 13, 2012
    Date of Patent: August 29, 2017
    Assignee: JAPAN SCIENCE AND TECHNOLOGY AGENCY
    Inventors: Tatsuo Kaneko, Akio Miyazato, Seiji Tateyama, Phruetchika Suvannasara, Yuuki Oka
  • Patent number: 9128449
    Abstract: A fixing device includes a heating body; first and second coils for induction heating that heat the heating body by an induction heating method; a first switching element connected to the first coil for induction heating; a second switching element connected to the second coil for induction heating; a driving signal transmission unit that sends a first drive signal to the first switching element and a second drive signal to the second switching element so that the first switching element and the second switching element operate at the same timing to apply a first input voltage to the first coil for induction heating and a second input voltage to the second coil for induction heating; and a voltage drop unit that steps down the first input voltage applied to the first coil for induction heating so that the first input voltage is lower than the second input voltage.
    Type: Grant
    Filed: June 25, 2014
    Date of Patent: September 8, 2015
    Assignee: Ricoh Company, Ltd.
    Inventors: Masataka Akaishi, Tsuyoshi Ueno, Motokazu Hasegawa, Yuuki Oka
  • Publication number: 20150010319
    Abstract: A fixing device includes a heating body; first and second coils for induction heating that heat the heating body by an induction heating method; a first switching element connected to the first coil for induction heating; a second switching element connected to the second coil for induction heating; a driving signal transmission unit that sends a first drive signal to the first switching element and a second drive signal to the second switching element so that the first switching element and the second switching element operate at the same timing to apply a first input voltage to the first coil for induction heating and a second input voltage to the second coil for induction heating; and a voltage drop unit that steps down the first input voltage applied to the first coil for induction heating so that the first input voltage is lower than the second input voltage.
    Type: Application
    Filed: June 25, 2014
    Publication date: January 8, 2015
    Applicant: RICOH COMPANY, LTD.
    Inventors: Masataka AKAISHI, Tsuyoshi UENO, Motokazu HASEGAWA, Yuuki OKA
  • Publication number: 20140323679
    Abstract: To provide a polymer material having properties that allow the polymer material to replace a polyimide and a polyamide synthesized from a petroleum raw material, said polymer material being synthesized from a raw material derived from natural molecules. [Solution] This polymer material is obtained by polymerizing a polymer raw material comprising a dimer of 4-amino cinnamic acid or a dimer of a 4-amino cinnamic acid derivative, which are natural molecules, wherein the carboxyl group is protected by an alkyl chain. The TGA curve of a polyamide acid (PAA-1) and a polyimide (PI-1) according to the present invention is shown in FIG. 5.
    Type: Application
    Filed: November 13, 2012
    Publication date: October 30, 2014
    Applicant: JAPAN ADVANCED INSTITUTE OF SCIENCE AND TECHNOLOGY
    Inventors: Tatsuo Kaneko, Akio Miyazato, Seiji Tateyama, Phruetchika Suvannasara, Yuuki Oka
  • Publication number: 20140305925
    Abstract: A fixing device includes a fixing member, which includes heat-generating layer, and an induction heater to inductively heat the fixing member. The induction heater includes an excitation coil disposed facing an outer circumferential surface of the fixing member to generate a magnetic flux, a ferromagnetic core assembly containing a ferromagnetic core to form a magnetic path to direct the magnetic flux generated by the excitation coil to the fixing member, and a holder to hold the excitation coil and the ferromagnetic core assembly. The ferromagnetic core is insert-molded in and covered by the holder. The holder has a plurality of spherical marks created by a plurality of stabilizing members each having a spherical tip to stabilize the ferromagnetic core in a mold.
    Type: Application
    Filed: March 26, 2014
    Publication date: October 16, 2014
    Applicant: RICOH COMPANY, LTD.
    Inventors: Yuuki OKA, Yukari ISOE, Motokazu HASEGAWA