Patents by Inventor Fumihiro Dasai

Fumihiro Dasai 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: 10309922
    Abstract: Proposed is a device for detecting a chemical/physical phenomenon, in which, via a novel scheme, charges are accumulated in a charge accumulation region. An amount of charges thus accumulated reflects the potential of a sensing region and the potential corresponds to an external environment (chemical phenomenon or physical phenomenon) to be detected. A charge accumulation region 5 includes a first potential well region FD1 that is continuous with a sensing region 3, the boundary potential of the charges held in the first potential well region FD1 being made equal to the potential of the sensing region 3, whereby the potential of the sensing region 3 is made to be reflected in the amount of charges held in the first potential well region FD1.
    Type: Grant
    Filed: February 19, 2016
    Date of Patent: June 4, 2019
    Assignee: NATIONAL UNIVERSITY CORPORATION TOYOHASHI UNIVERSITY OF TECHNOLOGY
    Inventors: Fumihiro Dasai, Kazuaki Sawada
  • Patent number: 9976981
    Abstract: Provided is a charge-transfer-type sensor suitable for high integration while eliminating a potential barrier. A sensor provided with a semiconductor substrate 10 partitioned into a sensing region 5 in which a potential varies in corresponding fashion to a variation in the external environment, a charge input region 2 for supplying charges to the sensing region 5, an input charge control region 3 interposed between the sensing region 5 and the charge input region 2, and a charge accumulation region 7 for accumulating electric charges transported from the sensing region 5, the sensor for detecting the amount of electric charges accumulated in the charge accumulation region 7, wherein a diffusion layer 4 is formed between the input charge control region 3 and the sensing region 5 of the substrate 10, and dopants for producing charges having the same polarity as the charges supplied from the charge input region 2 are diffused in the diffusion layer 4.
    Type: Grant
    Filed: January 6, 2016
    Date of Patent: May 22, 2018
    Assignee: National University Corporation Toyohashi University of Technology
    Inventors: Fumihiro Dasai, Kazuaki Sawada
  • Patent number: 9915629
    Abstract: The purpose of the present invention is to measure pH of a sample with high accuracy in a pH sensor array, without the use of a glass reference electrode. Each time that a sample is measured, the potential Vrm of the sample is identified, and the identified potential Vrm is used to calculate the pH. The outputs Voi1 and Voi2 of a first element and a second element located near one another in a sensor array are represented as follows. Voi1=Si1×pHi1+Gi1×Vrm+Ci1, Voi2=Si2×pHi2+Gi2×Vrm+Ci2. Voi is the output of the element, Si and Gi are sensitivity coefficients, and Ci is a constant, these values having been derived in advance. Here, where the potential Vrm is constant, and the elements located near one another are presumed to be at equal pH (pHi1=pHi2), the potential Vrm is identified by solving a linear equation with two unknowns.
    Type: Grant
    Filed: January 7, 2014
    Date of Patent: March 13, 2018
    Assignee: National University Corporation Toyohashi University of Technology
    Inventors: Fumihiro Dasai, Kazuaki Sawada, Masato Futagawa
  • Publication number: 20180052135
    Abstract: Proposed is a device for detecting a chemical/physical phenomenon, in which, via a novel scheme, charges are accumulated in a charge accumulation region. An amount of charges thus accumulated reflects the potential of a sensing region and the potential corresponds to an external environment (chemical phenomenon or physical phenomenon) to be detected. A charge accumulation region 5 includes a first potential well region FD1 that is continuous with a sensing region 3, the boundary potential of the charges held in the first potential well region FD1 being made equal to the potential of the sensing region 3, whereby the potential of the sensing region 3 is made to be reflected in the amount of charges held in the first potential well region FD1.
    Type: Application
    Filed: February 19, 2016
    Publication date: February 22, 2018
    Inventors: Fumihiro Dasai, Kazuaki Sawada
  • Publication number: 20180003671
    Abstract: Provided is a charge-transfer-type sensor suitable for high integration while eliminating a potential barrier. A sensor provided with a semiconductor substrate 10 partitioned into a sensing region 5 in which a potential varies in corresponding fashion to a variation in the external environment, a charge input region 2 for supplying charges to the sensing region 5, an input charge control region 3 interposed between the sensing region 5 and the charge input region 2, and a charge accumulation region 7 for accumulating electric charges transported from the sensing region 5, the sensor for detecting the amount of electric charges accumulated in the charge accumulation region 7, wherein a diffusion layer 4 is formed between the input charge control region 3 and the sensing region 5 of the substrate 10, and dopants for producing charges having the same polarity as the charges supplied from the charge input region 2 are diffused in the diffusion layer 4.
    Type: Application
    Filed: January 6, 2016
    Publication date: January 4, 2018
    Inventors: Fumihiro Dasai, Kazuaki Sawada
  • Patent number: 9766202
    Abstract: Provided are a device for detecting chemical and physical phenomenon suitable for high integration, and a method therefor. Rather than using a TG section signal to select pixels that require charge measurement, the on-off timing (the timing for moving the charge from a sensing section to an FD section) of the TG section is harmonized for all pixels, and the release or injection of the charge to the sensing section is separately controlled, whereby the charge is held only in sensing sections of pixels that require charge measurement, and the charge is emptied in sensing sections of pixels that do not require charge measurement. In this state, the TG section of all pixels can be opened at the same time, whereby the charge is transferred to the FD section from only the sensing sections holding a charge, and the charge level of the pixel is detected.
    Type: Grant
    Filed: July 13, 2012
    Date of Patent: September 19, 2017
    Assignee: National University Corporation Toyohashi University of Technology
    Inventors: Fumihiro Dasai, Kazuaki Sawada
  • Patent number: 9482641
    Abstract: Provided is a device adapted for detecting chemical and physical phenomena and suitable for high integration, and a method for controlling the detection device. When a plurality of pH-detecting devices are used, a variation in sensitivity occurs in each of the sensing units. The variation in sensitivity can be calibrated using a simple method. The amount of charge (output signal) delivered by each of the sensing units to a standard solution is determined, and the difference between the delivered charge amount and a standard charge amount (standard output signal) delivered by a standard sensing unit is determined. The capacity of the potential well of the sensing unit is changed, or the potential of a TG unit when a charge is delivered is changed, so as to cancel out the difference.
    Type: Grant
    Filed: August 9, 2012
    Date of Patent: November 1, 2016
    Assignee: National University Corporation Toyohashi University of Technology
    Inventors: Fumihiro Dasai, Kazuaki Sawada, Hirokazu Nakazawa
  • Publication number: 20150355127
    Abstract: The purpose of the present invention is to measure pH of a sample with high accuracy in a pH sensor array, without the use of a glass reference electrode. Each time that a sample is measured, the potential Vrm of the sample is identified, and the identified potential Vrm is used to calculate the pH. The outputs Voi1 and Voi2 of a first element and a second element located near one another in a sensor array are represented as follows. Voi1=Si1×pHi1+Gi1×Vrm+Ci1, Voi2=Si2×pHi2+Gi2×Vrm+Ci2. Voi is the output of the element, Si and Gi are sensitivity coefficients, and Ci is a constant, these values having been derived in advance. Here, where the potential Vrm is constant, and the elements located near one another are presumed to be at equal pH (pHi1=pHi2), the potential Vrm is identified by solving a linear equation with two unknowns.
    Type: Application
    Filed: January 7, 2014
    Publication date: December 10, 2015
    Applicant: National University Corporation Toyohashi University of Technology
    Inventors: Fumihiro Dasai, Kazuaki Sawada, Masato Futagawa
  • Publication number: 20140200842
    Abstract: Provided is a device adapted for detecting chemical and physical phenomena and suitable for high integration, and a method for controlling the detection device. When a plurality of pH-detecting devices are used, a variation in sensitivity occurs in each of the sensing units. The variation in sensitivity can be calibrated using a simple method. The amount of charge (output signal) delivered by each of the sensing units to a standard solution is determined, and the difference between the delivered charge amount and a standard charge amount (standard output signal) delivered by a standard sensing unit is determined. The capacity of the potential well of the sensing unit is changed, or the potential of a TG unit when a charge is delivered is changed, so as to cancel out the difference.
    Type: Application
    Filed: August 9, 2012
    Publication date: July 17, 2014
    Applicant: National University Corporation Toyohashi University of Technology
    Inventors: Fumihiro Dasai, Kazuaki Sawada, Hirokazu Nakazawa
  • Publication number: 20140139231
    Abstract: Provided are a device for detecting chemical and physical phenomenon suitable for high integration, and a method therefor. Rather than using a TG section signal to select pixels that require charge measurement, the on-off timing (the timing for moving the charge from a sensing section to an FD section) of the TG section is harmonized for all pixels, and the release or injection of the charge to the sensing section is separately controlled, whereby the charge is held only in sensing sections of pixels that require charge measurement, and the charge is emptied in sensing sections of pixels that do not require charge measurement. In this state, the TG section of all pixels can be opened at the same time, whereby the charge is transferred to the FD section from only the sensing sections holding a charge, and the charge level of the pixel is detected.
    Type: Application
    Filed: July 13, 2012
    Publication date: May 22, 2014
    Applicant: National University Corporation Toyohashi University of Technology
    Inventors: Fumihiro Dasai, Kazuaki Sawada
  • Patent number: 5886558
    Abstract: A semiconductor unit is composed of an analog unit, a digital unit, a signal line through which a signal is transmitted from the analog unit to the digital unit, an electric source line Vdd1 through which a high voltage is applied to the analog unit, an electric source line Vdd2 through which the high voltage is applied to the digital unit, an electric source line Vss1 through which a low voltage is applied to the analog unit, an electric source line Vss2 through which the low voltage is applied to the digital unit, and a protective circuit arranged between the electric source lines Vss1 and Vss2. The protective circuit functions to electrically connect the electric source line Vss1 and the electric source line Vss2 in cases where an electric potential difference between the electric source lines Vss1 and Vss2 exceeds a prescribed value. Similar protection can be provided between the high voltage source lines Vdd1 and Vdd2 or between the signal line and the second source lines Vdd2 and Vss2.
    Type: Grant
    Filed: August 27, 1996
    Date of Patent: March 23, 1999
    Assignee: Sanyo Electric Co., Ltd.
    Inventors: Hiroaki Iijima, Fumihiro Dasai, Tsutomu Fujino