Patents by Inventor Chung Shing Fan

Chung Shing Fan 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).

  • Signal distribution for patient-electrode measurements
    Patent number: 9585593
    Abstract: Apparatus for electrically connecting measurement apparatus to a biological subject, the apparatus including a signal delivery circuit including a current buffer having a current buffer input for receiving a signal from a signal source and a current buffer output for supplying a current to an electrode attached to the biological subject, and a voltage buffer having a voltage buffer input coupled to the current buffer output and a voltage buffer output for providing a voltage signal indicative of a voltage at the electrode, to a sensor.
    Type: Grant
    Filed: November 18, 2010
    Date of Patent: March 7, 2017
    Inventors: Chung Shing Fan, Joel Ironstone, Kenneth Carless Smith
  • Active guarding for reduction of resistive and capacitive signal loading with adjustable control of compensation level
    Patent number: 8487686
    Abstract: In various embodiments, applicants' teachings are related to an active guarding circuit and method for reducing parasitic impedance signal loading on a signal-transmission channel that is shunted by a parasitic impedance. The presence of an electrical signal on the signal-transmission channel causes a leakage current to flow through the parasitic impedance. In various embodiments, the circuit comprises an amplifier and an impedance, one terminal of the impedance is coupled to the signal-transmission channel. The input of the amplifier is coupled to the signal-transmission channel and the output is coupled to the other terminal of the impedance so as to cause a compensation current to flow through the impedance. The gain of the amplifier and the value of the impedance are selected so that the compensation current has a magnitude substantially equal to the leakage current magnitude.
    Type: Grant
    Filed: March 31, 2008
    Date of Patent: July 16, 2013
    Assignee: Impedimed Limited
    Inventors: Joel Ironstone, David Wang, Frank Zhang, Chung Shing Fan, Morrie Altmejd, Kenneth Carless Smith
  • SYSTEM AND CIRCUIT FOR DISTRIBUTION OF PRECISE CURRENTS TO NUMEROUS PATIENT ELECTRODES AND FOR NON-INVASIVE PATIENT-ELECTRODE VOLTAGE MEASUREMENTS
    Publication number: 20130102920
    Abstract: Apparatus for electrically connecting measurement apparatus to a biological subject, the apparatus including a signal delivery circuit including a current buffer having a current buffer input for receiving a signal from a signal source and a current buffer output for supplying a current to an electrode attached to the biological subject, and a voltage buffer having a voltage buffer input coupled to the current buffer output and a voltage buffer output for providing a voltage signal indicative of a voltage at the electrode, to a sensor.
    Type: Application
    Filed: November 18, 2010
    Publication date: April 25, 2013
    Applicant: Impedimed Limited
    Inventors: Chung Shing Fan, Joel Ironstone, Kenneth Carless Smith
  • ACTIVE GUARDING FOR REDUCTION OF RESISTIVE AND CAPACITIVE SIGNAL LOADING WITH ADJUSTABLE CONTROL OF COMPENSATION LEVEL
    Publication number: 20100109739
    Abstract: In various embodiments, applicants' teachings are related to an active guarding circuit and method for reducing parasitic impedance signal loading on a signal-transmission channel that is shunted by a parasitic impedance. The presence of an electrical signal on the signal-transmission channel causes a leakage current to flow through the parasitic impedance. In various embodiments, the circuit comprises an amplifier and an impedance, one terminal of the impedance is coupled to the signal-transmission channel. The input of the amplifier is coupled to the signal-transmission channel and the output is coupled to the other terminal of the impedance so as to cause a compensation current to flow through the impedance. The gain of the amplifier and the value of the impedance are selected so that the compensation current has a magnitude substantially equal to the leakage current magnitude.
    Type: Application
    Filed: March 31, 2008
    Publication date: May 6, 2010
    Applicant: Impedimed Limited
    Inventors: Joel Ironstone, David Wang, Frank Zhang, Chung Shing Fan, Morrie Altmejd, Kenneth Carless Smith