Patents by Inventor Takaaki Negoro

Takaaki Negoro 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: 20150264280
    Abstract: An imaging device includes a photoelectric conversion element which photoelectrically converts incident light and generates a charge, accumulates and amplifies the charge, and outputs a photocurrent, wherein a level of an output signal when a charge which is accumulated in the photoelectric conversion element is outputted over a saturated amount of accumulable charge includes a level of an output signal of a charge of a photocurrent of DC component which is generated in the photoelectric conversion element and outputted during a readout time when the charge which is accumulated in the photoelectric conversion element is outputted.
    Type: Application
    Filed: March 9, 2015
    Publication date: September 17, 2015
    Applicant: RICOH COMPANY, LTD.
    Inventors: Kazuhiro YONEDA, Hirofumi WATANABE, Takaaki NEGORO, Katsuhiko AISU, Yasukazu NAKATANI, Katsuyuki SAKURANO
  • Publication number: 20150214413
    Abstract: A phototransistor includes a first emitter region, a first base region having at least a portion exposed to a light-receiving side, and a first collector region in this order from the light-receiving side in a depth direction. The first collector region includes a second collector region and a third collector region that is in contact with a downstream side of the second collector region in the depth direction and has a resistance lower than that of the second collector region. The phototransistor further includes a first region that is spaced away from the first base region at an outer side of the first base region on a light-receiving side surface thereof, the first region having a conductivity type opposite to that of the first collector region.
    Type: Application
    Filed: January 26, 2015
    Publication date: July 30, 2015
    Applicant: RICOH COMPANY, LTD.
    Inventors: Takaaki NEGORO, Yoshihiko MIKI, Katsuyuki SAKURANO, Keiji TSUDA, Hirofumi WATANABE
  • Publication number: 20150171129
    Abstract: A semiconductor device and a method of manufacturing a semiconductor device are disclosed. The method includes forming a trench, in a vertical direction of a semiconductor substrate having a plurality of photoelectric converting elements arranged on the semiconductor device, at positions between the photoelectric converting elements that are next to each other, forming a first conductive-material layer in and above the trench by implanting a first conductive material into the trench after an oxide film is formed on an inner wall of the trench, forming a first conductor by removing the first conductive-material layer excluding a first conductive portion of the first conductive-material layer implanted into the trench, and forming an upper gate electrode above the first conductor, the upper gate electrode configured to be conductive with the first conductor. The semiconductor device includes a semiconductor substrate, an image sensor, a trench, a first conductor, and an upper gate electrode.
    Type: Application
    Filed: December 4, 2014
    Publication date: June 18, 2015
    Applicant: RICOH COMPANY, LTD.
    Inventors: Katsuyuki Sakurano, Takaaki Negoro, Katsuhiko Aisu, Kazuhiro Yoneda, Yasukazu Nakatani, Hirofumi Watanabe
  • Patent number: 9059065
    Abstract: Provided is a method of varying the gain of an amplifying photoelectric conversion device and a variable gain photoelectric conversion device which are capable of achieving both signal processing under low illuminance and high-current processing under high light intensity, and thereby capable of securing a wide dynamic range. An amplifying photoelectric conversion part includes a photoelectric conversion element and amplification transistors forming a Darlington circuit. The sources and the drains of field-effect transistors are connected to the bases and the emitters of the amplification transistors, respectively. The gates of the field-effect transistors each function as a gain control part.
    Type: Grant
    Filed: March 18, 2013
    Date of Patent: June 16, 2015
    Assignees: National Institute of Advanced Industrial Science and Technology, RICOH COMPANY, LTD.
    Inventors: Yutaka Hayashi, Kazuhiro Yoneda, Hirofumi Watanabe, Katsuhiko Aisu, Takaaki Negoro, Toshitaka Ota, Yasushi Nagamune
  • Publication number: 20150076572
    Abstract: A semiconductor device includes a semiconductor substrate, a plurality of photoelectric conversion elements arranged on the semiconductor substrate to collectively form an image sensor, a plurality of trenches each formed between the photoelectric conversion elements adjacent to each other, and a plurality of impurity diffusion layers each provided at a bottom of the trench at a position deeper than a p-n junction of the photoelectric conversion element.
    Type: Application
    Filed: September 10, 2014
    Publication date: March 19, 2015
    Applicant: RICOH COMPANY, LTD.
    Inventors: Katsuyuki Sakurano, Hirobumi Watanabe, Takaaki Negoro, Katsuhiko Aisu, Kazuhiro Yoneda
  • Publication number: 20150070546
    Abstract: An imaging device includes at least one pixel having a phototransistor which converts light energy into signal charge and varies an amplification factor relative to the intensity of the received light energy, wherein the signal charge of the phototransistor is read out while receiving the light energy with the phototransistor for each pixel.
    Type: Application
    Filed: August 20, 2014
    Publication date: March 12, 2015
    Applicant: RICOH COMPANY, LTD.
    Inventors: Takaaki Negoro, Hirofumi Watanabe, Katsuhiko Aisu, Kazuhiro Yoneda, Katsuyuki Sakurano
  • Patent number: 8975939
    Abstract: A voltage clamp circuit includes a power supply, a first element connected with the power supply to output a constant current, a third element configured to allow a current to pass through when a voltage of a predetermined value or more is applied; and a second element configured to output a voltage according to a voltage generated by the first and third elements.
    Type: Grant
    Filed: June 28, 2011
    Date of Patent: March 10, 2015
    Assignee: Ricoh Company, Ltd.
    Inventors: Takaaki Negoro, Shinichi Kubota, Koichi Morino
  • Publication number: 20140367550
    Abstract: A photoelectric conversion device includes a first output line, a second output line; and a photoelectric conversion cell. The photoelectric conversion cell further includes, a photoelectric conversion element configured to generate an output current corresponding to an intensity of incident light, a first switch element configured to transmit the first output current to the first output line according to a first control signal, and a second switch element configured to transmit the second output current to second output line according to a second control signal. As a result, the photoelectric conversion device can be provided to generate rapidly the image data with wide dynamic range without the need for complex control outside of the photoelectric conversion device.
    Type: Application
    Filed: June 16, 2014
    Publication date: December 18, 2014
    Inventors: Katsuhiko AISU, Takaaki Negoro, Kazuhiro Yoneda, Katsuyuki Sakurano, Hirobumi Watanabe
  • Patent number: 8878599
    Abstract: A semiconductor integrated circuit device includes a power-supply terminal to which a power-supply voltage is input; and multiple MOS transistors including an Nch deplete mode MOS transistor functioning as a current source and at least one Pch enhancement mode MOS transistor formed on a silicon-on-insulator substrate including a silicon substrate, a buried-oxide film, and a silicon activate layer, each of the multiple MOS transistors dimensioned so that a bottom of a source diffusion layer and a bottom of a drain diffusion layer reach the buried-oxide film, the at least one Pch enhancement mode MOS transistor being connected to the supply terminal through the Nch depletion mode MOS transistor. The Nch depletion mode MOS transistor has electrical characteristics such that a source voltage thereof is higher than a silicon substrate voltage thereof and a saturation current of the Nch depletion mode MOS transistor is decreased.
    Type: Grant
    Filed: August 3, 2011
    Date of Patent: November 4, 2014
    Assignee: Ricoh Company, Ltd.
    Inventor: Takaaki Negoro
  • Publication number: 20140239158
    Abstract: A photoelectric converter includes a first pn junction comprised of at least two semiconductor regions of different conductivity types, and a first field-effect transistor including a first source connected with one of the semiconductor regions, a first drain, a first insulated gate and a same conductivity type channel as that of the one of the semiconductor regions. The first drain is supplied with a second potential at which the first pn junction becomes zero-biased or reverse-biased relative to a potential of the other of the semiconductor regions. When the first source turns to a first potential and the one of the semiconductor regions becomes zero-biased or reverse-biased relative to the other semiconductor regions, the first pn junction is controlled not to be biased by a deep forward voltage by supplying a first gate potential to the first insulated gate, even when either of the semiconductor regions is exposed to light.
    Type: Application
    Filed: October 5, 2012
    Publication date: August 28, 2014
    Applicants: NATIONAL INSTITUTE OF ADVANCED INDUSTRIAL SCIENCE, RICOH COMPANY, LTD.
    Inventors: Yutaka Hayashi, Toshitaka Ota, Yasushi Nagamune, Hirofumi Watanabe, Takaaki Negoro, Kazunari Kimino
  • Publication number: 20130240716
    Abstract: Provided is a method of varying the gain of an amplifying photoelectric conversion device and a variable gain photoelectric conversion device which are capable of achieving both signal processing under low illuminance and high-current processing under high light intensity, and thereby capable of securing a wide dynamic range. An amplifying photoelectric conversion part includes a photoelectric conversion element and amplification transistors forming a Darlington circuit. The sources and the drains of field-effect transistors are connected to the bases and the emitters of the amplification transistors, respectively. The gates of the field-effect transistors each function as a gain control part.
    Type: Application
    Filed: March 18, 2013
    Publication date: September 19, 2013
    Applicants: RICOH COMPANY, LTD., National Institute of Advanced Industrial Science and Technology
    Inventors: Yutaka Hayashi, Kazuhiro YONEDA, Hirofumi WATANABE, Katsuhiko AISU, Takaaki NEGORO, Toshitaka OTA, Yasushi NAGAMUNE
  • Publication number: 20130234277
    Abstract: The invention relates to a semiconductor device having a vertical transistor bipolar structure of emitter, base, and collector formed in this order from a semiconductor substrate surface in a depth direction. The semiconductor device includes an electrode embedded from the semiconductor substrate surface into the inside and insulated by an oxide film. In the surface of the substrate, a first-conductivity-type first semiconductor region, a second-conductivity-type second semiconductor region, and a first-conductivity-type third semiconductor region are arranged, from the surface side, inside a semiconductor device region surrounded by the electrode and along the electrode with the oxide film interposed therebetween, the second semiconductor region located below the first semiconductor region, the third semiconductor region located below the second semiconductor region.
    Type: Application
    Filed: March 11, 2013
    Publication date: September 12, 2013
    Applicants: Ricoh Company, LTD., National Institute of Advanced Industrial Science and Technology
    Inventors: Takaaki Negoro, Hirofumi Watanabe, Yutaka Hayashi, Toshitaka Ota, Yasushi Nagamune
  • Publication number: 20130187030
    Abstract: A sense circuit includes a differential amplifier circuit including an inverting input section, a non-inverting input section and an output section, an electrical capacitor connected between the inverting input section and the output section, and a field effect transistor including a source, a drain, and a gate. One of the source and the drain is connected to the inverting input section, and the other of the source and the drain is connected to the output section. A reference potential is supplied to the non-inverting input section, and an output section of a photoelectric conversion cell having an added switching function is connected to the inverting input section.
    Type: Application
    Filed: January 18, 2013
    Publication date: July 25, 2013
    Applicants: RICOH COMPANY, LTD., National Institute of Advanced Industrial Science and Technology
    Inventors: Yutaka Hayashi, Toshitaka Ota, Yasushi Nagamune, Hirofumi Watanabe, Kazuhiro Yoneda, Katsuhiko Aisu, Takaaki Negoro
  • Patent number: 8169039
    Abstract: A disclosed semiconductor device includes an MOS transistor having an N-type low-concentration drain region, a source region, an ohmic drain region, a P-type channel region, an ohmic channel region, a gate isolation film, and a gate electrode. The N-type low-concentration drain region includes two low-concentration drain layers in which the N-type impurity concentration of the upper layer is higher than that of the lower layer; the P-type channel region includes two channel layers in which the P-type impurity concentration of the upper layer is lower than that of the lower layer; and the gate electrode is formed on the P-type channel region and the N-type low-concentration drain region and disposed to be separated from the ohmic drain region when viewed from the top.
    Type: Grant
    Filed: August 2, 2010
    Date of Patent: May 1, 2012
    Assignee: Ricoh Company, Ltd.
    Inventor: Takaaki Negoro
  • Publication number: 20120032733
    Abstract: A semiconductor integrated circuit device includes a power-supply terminal to which a power-supply voltage is input; and multiple MOS transistors including an Nch deplete mode MOS transistor functioning as a current source and at least one Pch enhancement mode MOS transistor formed on a silicon-on-insulator substrate including a silicon substrate, a buried-oxide film, and a silicon activate layer, each of the multiple MOS transistors dimensioned so that a bottom of a source diffusion layer and a bottom of a drain diffusion layer reach the buried-oxide film, the at least one Pch enhancement mode MOS transistor being connected to the supply terminal through the Nch depletion mode MOS transistor. The Nch depletion mode MOS transistor has electrical characteristics such that a source voltage thereof is higher than a silicon substrate voltage thereof and a saturation current of the Nch depletion mode MOS transistor is decreased.
    Type: Application
    Filed: August 3, 2011
    Publication date: February 9, 2012
    Applicant: RICOH COMPANY, LTD.
    Inventor: Takaaki NEGORO
  • Publication number: 20120013383
    Abstract: A voltage clamp circuit includes a power supply, a first element connected with the power supply to output a constant current, a third element configured to allow a current to pass through when a voltage of a predetermined value or more is applied; and a second element configured to output a voltage according to a voltage generated by the first and third elements.
    Type: Application
    Filed: June 28, 2011
    Publication date: January 19, 2012
    Applicant: RICOH COMPANY, LTD.
    Inventors: Takaaki Negoro, Shinichi Kubota, Koichi Morino
  • Publication number: 20110042745
    Abstract: A disclosed semiconductor device includes an MOS transistor having an N-type low-concentration drain region, a source region, an ohmic drain region, a P-type channel region, an ohmic channel region, a gate isolation film, and a gate electrode. The N-type low-concentration drain region includes two low-concentration drain layers in which the N-type impurity concentration of the upper layer is higher than that of the lower layer; the P-type channel region includes two channel layers in which the P-type impurity concentration of the upper layer is lower than that of the lower layer; and the gate electrode is formed on the P-type channel region and the N-type low-concentration drain region and disposed to be separated from the ohmic drain region when viewed from the top.
    Type: Application
    Filed: August 2, 2010
    Publication date: February 24, 2011
    Applicant: RICOH COMPANY, LTD.
    Inventor: Takaaki NEGORO
  • Patent number: 7755337
    Abstract: A current sensing circuit for sensing an output current generated by a voltage regulator includes a first double-diffused metal-oxide semiconductor transistor and a current-voltage converter. The first double-diffused metal-oxide semiconductor transistor has a first gate terminal to receive an output control signal from a control circuit of the voltage regulator. The first double-diffused metal-oxide semiconductor transistor is configured to output a current proportional to the output current according to the output control signal. The current-voltage converter is connected to the first double-diffused metal-oxide semiconductor transistor. The current-voltage converter is configured to convert the proportional current to a corresponding voltage.
    Type: Grant
    Filed: October 30, 2007
    Date of Patent: July 13, 2010
    Assignee: Ricoh Company, Ltd.
    Inventor: Takaaki Negoro
  • Patent number: 7728566
    Abstract: A voltage regulator having a MOS transistor driver includes a p-channel MOS transistor at a voltage input terminal Vin and a p-channel MOS transistor at a voltage output terminal Vout. A drain of the input side p-channel MOS transistor is connected to the voltage input terminal Vin. A threshold voltage or a voltage lower than the threshold voltage is applied to a gate of the input side p-channel MOS transistor. A drain of the output side p-channel MOS transistor is connected to the voltage output terminal Vout. A current flowing through the input side p-channel MOS transistor drives a voltage regulator circuit and the output side p-channel MOS transistor.
    Type: Grant
    Filed: May 27, 2008
    Date of Patent: June 1, 2010
    Assignee: Ricoh Company, Ltd.
    Inventors: Takaaki Negoro, Koichi Morino
  • Patent number: 7719242
    Abstract: A voltage regulator is disclosed that includes an output transistor outputting a current according to an input control signal to an output terminal; a control circuit part controlling the operation of the output transistor; a switching circuit part connecting the substrate gate and the gate of the output transistor to one of the input terminal and the output terminal and one of the output of the control circuit part and the output terminal, respectively, in accordance with the relationship in magnitude between a voltage at an input terminal and a voltage at the output terminal; a first rectifier element connected between the input terminal and a power supply end; and a second rectifier element connected between the output terminal and the power supply end.
    Type: Grant
    Filed: July 2, 2007
    Date of Patent: May 18, 2010
    Assignee: Ricoh Company, Ltd.
    Inventor: Takaaki Negoro