Patents by Inventor Takeshi Nagahisa

Takeshi Nagahisa 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: 9923546
    Abstract: Two types of high-pass filter circuit and a band-pass filter circuit are provided. Both types of high-pass filter circuit include a capacitor configured to input an input signal, a resistor connected between an output terminal of the capacitor and a prescribed bias voltage, and a signal output circuit connected to the output terminal of the capacitor and configured to buffer-amplify the input signal for output. In one of the two types of high-pass filter circuits, the resistor is formed on an SOI semiconductor substrate and includes two PN junction diodes that are inversely connected to each other in parallel. In the other one of the high-pass filter circuits, the resistor is formed on an SOI semiconductor substrate and includes two MOS transistors that are inversely connected to each other in parallel.
    Type: Grant
    Filed: January 26, 2015
    Date of Patent: March 20, 2018
    Assignee: RICOH COMPANY, LTD.
    Inventors: Takeshi Nagahisa, Yasukazu Nakatani
  • Patent number: 9880058
    Abstract: A semiconductor integrated circuit includes an acquisition unit configured to acquire a value outputted from an infrared sensor in response to an infrared ray received from an object, and a value outputted from a temperature sensor as a function of measured temperature of the infrared sensor; a second-temperature identification circuit configured to identify a second temperature which is a temperature of the object when the temperature of the infrared sensor corresponding to a measured value which is the output value of the infrared sensor, is the first temperature, by referring to the correspondence; a third-temperature identification circuit configured to identify a third temperature which is the temperature of the infrared sensor in outputting the measured value; and a calculation circuit configured to calculate a fourth temperature which is a temperature of the object on the basis of the first temperature, the second temperature, and the third temperature.
    Type: Grant
    Filed: December 2, 2014
    Date of Patent: January 30, 2018
    Assignee: RICOH COMPANY, LTD.
    Inventor: Takeshi Nagahisa
  • Publication number: 20160338154
    Abstract: A high frequency dielectric heater includes a high frequency power supply configured to supply a power having a high frequency to heat a subject, electrodes including a positive electrode and a negative electrode, each electrode being disposed in such a manner that the longitudinal direction of each electrode crosses with the transfer direction of the subject and having a surface at least part of which is parallel to the subject, and a transfer device to transfer the subject.
    Type: Application
    Filed: April 29, 2016
    Publication date: November 17, 2016
    Inventor: Takeshi NAGAHISA
  • Patent number: 9246446
    Abstract: A chopper amplifier includes a chopper modulator to modulate a certain detection signal and a bias voltage by a certain control signal and output a chopper modulation signal, a first differential amplifier to differentially amplify the chopper modulation signal from the chopper modulator and output a differential modulation signal, a chopper demodulator to demodulate the differential modulation signal from the first differential amplifier by the control signal and output a demodulation signal, a second differential amplifier to extract a detection signal component from the demodulation signal, and a plurality of filters connected at an input terminal of the second differential amplifier and having different cutoff frequencies from each other relative to the demodulation signal.
    Type: Grant
    Filed: April 9, 2014
    Date of Patent: January 26, 2016
    Assignee: RICOH COMPANY, LTD.
    Inventor: Takeshi Nagahisa
  • Publication number: 20150229293
    Abstract: Two types of high-pass filter circuit and a band-pass filter circuit are provided. Both types of high-pass filter circuit include a capacitor configured to input an input signal, a resistor connected between an output terminal of the capacitor and a prescribed bias voltage, and a signal output circuit connected to the output terminal of the capacitor and configured to buffer-amplify the input signal for output. In one of the two types of high-pass filter circuits, the resistor is formed on an SOI semiconductor substrate and includes two PN junction diodes that are inversely connected to each other in parallel. In the other one of the high-pass filter circuits, the resistor is formed on an SOI semiconductor substrate and includes two MOS transistors that are inversely connected to each other in parallel.
    Type: Application
    Filed: January 26, 2015
    Publication date: August 13, 2015
    Applicant: RICOH COMPANY, LTD.
    Inventors: Takeshi NAGAHISA, Yasukazu NAKATANI
  • Patent number: 9071208
    Abstract: A signal amplification circuit includes an input terminal; a first chopper modulation circuit; a first amplifier having an amplification circuit and a chopper demodulation circuit, a capacitance feedback circuit having a second chopper modulation circuit, a first switch constituting a voltage follower circuit with the amplification circuit; a second switch; a second amplifier to convert the differential output signal from the second output terminal into a single-end signal; and a filter to pass at least a predetermined frequency component of the chopping frequency from the single-end signal from the second amplifier to output an output signal of the signal amplification circuit.
    Type: Grant
    Filed: September 4, 2013
    Date of Patent: June 30, 2015
    Assignee: RICOH COMPANY, LTD.
    Inventor: Takeshi Nagahisa
  • Publication number: 20150168220
    Abstract: A semiconductor integrated circuit includes an acquisition unit configured to acquire a value outputted from an infrared sensor in response to an infrared ray received from an object, and a value outputted from a temperature sensor as a function of measured temperature of the infrared sensor; a second-temperature identification circuit configured to identify a second temperature which is a temperature of the object when the temperature of the infrared sensor corresponding to a measured value which is the output value of the infrared sensor, is the first temperature, by referring to the correspondence; a third-temperature identification circuit configured to identify a third temperature which is the temperature of the infrared sensor in outputting the measured value; and a calculation circuit configured to calculate a fourth temperature which is a temperature of the object on the basis of the first temperature, the second temperature, and the third temperature.
    Type: Application
    Filed: December 2, 2014
    Publication date: June 18, 2015
    Applicant: RICOH COMPANY, LTD.
    Inventor: Takeshi Nagahisa
  • Publication number: 20150069245
    Abstract: A human body detector is disclosed. The human body detector comprises an infrared sensor which detects a light amount change of infrared rays which enter from a detection target area, and a controller which determines the presence or absence of a human body in the detection target area according to the light amount change of the infrared rays. The infrared sensor is configured to detect the light amount change of the infrared rays which enter from a plurality of cell sections which are formed by dividing the detection target area, and the controller is configured to identify an outer peripheral area and an inside area, and determine the presence and absence of the human body in the detection target area.
    Type: Application
    Filed: August 18, 2014
    Publication date: March 12, 2015
    Applicant: RICOH COMPANY, LTD.
    Inventor: Takeshi Nagahisa
  • Patent number: 8969810
    Abstract: An infrared sensor device includes a plurality of infrared sensors that is provided in a plurality of divided areas in which an infrared-receiving area is radially divided in one plane; a detector that detects presence or absence of movement of an object in the infrared-receiving area for each of the divided areas based on an output of the infrared sensor; and a determiner that determines whether the object is in a detection area in a predetermined distance range from the infrared sensor, based on an arrangement pattern of the divided areas in which the movement of the object is detected, in an alignment of the divided areas in the infrared-receiving areas.
    Type: Grant
    Filed: March 12, 2013
    Date of Patent: March 3, 2015
    Assignee: Ricoh Company, Ltd.
    Inventors: Takeshi Nagahisa, Katsuhiko Aisu, Hirofumi Watanabe
  • Publication number: 20140312967
    Abstract: A chopper amplifier includes a chopper modulator to modulate a certain detection signal and a bias voltage by a certain control signal and output a chopper modulation signal, a first differential amplifier to differentially amplify the chopper modulation signal from the chopper modulator and output a differential modulation signal, a chopper demodulator to demodulate the differential modulation signal from the first differential amplifier by the control signal and output a demodulation signal, a second differential amplifier to extract a detection signal component from the demodulation signal, and a plurality of filters connected at an input terminal of the second differential amplifier and having different cutoff frequencies from each other relative to the demodulation signal.
    Type: Application
    Filed: April 9, 2014
    Publication date: October 23, 2014
    Applicant: RICOH COMPANY, LTD.
    Inventor: Takeshi Nagahisa
  • Publication number: 20140077872
    Abstract: A signal amplification circuit includes an input terminal; a first chopper modulation circuit; a first amplifier having an amplification circuit and a chopper demodulation circuit, a capacitance feedback circuit having a second chopper modulation circuit, a first switch constituting a voltage follower circuit with the amplification circuit; a second switch; a second amplifier to convert the differential output signal from the second output terminal into a single-end signal; and a filter to pass at least a predetermined frequency component of the chopping frequency from the single-end signal from the second amplifier to output an output signal of the signal amplification circuit.
    Type: Application
    Filed: September 4, 2013
    Publication date: March 20, 2014
    Applicant: RICOH COMPANY, LTD.
    Inventor: Takeshi Nagahisa
  • Publication number: 20130284931
    Abstract: An infrared sensor device includes a plurality of infrared sensors that is provided in a plurality of divided areas in which an infrared-receiving area is radially divided in one plane; a detector that detects presence or absence of movement of an object in the infrared-receiving area for each of the divided areas based on an output of the infrared sensor; and a determiner that determines whether the object is in a detection area in a predetermined distance range from the infrared sensor, based on an arrangement pattern of the divided areas in which the movement of the object is detected, in an alignment of the divided areas in the infrared-receiving areas.
    Type: Application
    Filed: March 12, 2013
    Publication date: October 31, 2013
    Applicant: RICOH COMPANY, LTD.
    Inventors: Takeshi Nagahisa, Katsuhiko Aisu, Hirofumi Watanabe
  • Patent number: 8152363
    Abstract: A temperature detection circuit includes a first voltage source circuit to generate a first voltage having a temperature dependence by utilizing a work function difference of gate electrodes of a plurality of field effect transistors, a second voltage source circuit to generate a reference voltage having no temperature dependence by utilizing a work function difference of gate electrodes of a plurality of field effect transistors, a correction circuit configured to correct the reference voltage and output a corrected voltage, and a subtraction amplifier configured to subtract the corrected voltage from the first voltage, amplify a resulting subtracted voltage, and output a resulting amplified voltage as a correction voltage signal to adjust a temperature coefficient of the correction voltage signal.
    Type: Grant
    Filed: July 1, 2008
    Date of Patent: April 10, 2012
    Assignee: Ricoh Company, Ltd.
    Inventor: Takeshi Nagahisa
  • Publication number: 20090010301
    Abstract: A temperature detection circuit includes a first voltage source circuit to generate a first voltage having a temperature dependence by utilizing a work function difference of gate electrodes of a plurality of field effect transistors, a second voltage source circuit to generate a reference voltage having no temperature dependence by utilizing a work function difference of gate electrodes of a plurality of field effect transistors, a correction circuit configured to correct the reference voltage and output a corrected voltage, and a subtraction amplifier configured to subtract the corrected voltage from the first voltage, amplify a resulting subtracted voltage, and output a resulting amplified voltage as a correction voltage signal to adjust a temperature coefficient of the correction voltage signal.
    Type: Application
    Filed: July 1, 2008
    Publication date: January 8, 2009
    Inventor: Takeshi Nagahisa