Patents by Inventor John Douglas Fraser

John Douglas Fraser 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: 8203912
    Abstract: A capacitive ultrasound transducer includes a first electrode, a second electrode, and a third electrode, the third electrode including a central region disposed in collapsibly spaced relation with the first electrode, and a peripheral region disposed outward of the central region and disposed in collapsibly spaced relation with the second electrode. The transducer further includes a layer of a high dielectric constant material disposed between the third electrode and the first electrode, and between the third electrode and the second electrode. The transducer may be operable in a collapsed mode wherein the peripheral region of the third electrode oscillates relative to the second electrode, and the central region of the third electrode is fully collapsed with respect to the first electrode such that the dielectric layer is sandwiched therebetween. Piezoelectric actuation, such as d31 and d33 mode piezoelectric actuation, may further be included.
    Type: Grant
    Filed: July 31, 2008
    Date of Patent: June 19, 2012
    Assignee: Koninklijke Philips Electronics N.V.
    Inventors: Aarnoud Laurens Roest, Klaus Reimann, Mareike Klee, Jozef Thomas Martinus van Beek, John Douglas Fraser
  • Publication number: 20120143062
    Abstract: A magnetic connection system suitable for use with a wireless ultrasound probe which utilizes a plurality of magnets to facilitate coupling between said probe and a diagnostic or clinical device in a manner which minimizes the effects of stray magnetic fields on the device.
    Type: Application
    Filed: August 3, 2010
    Publication date: June 7, 2012
    Applicant: KONINKLIJKE PHILIPS ELECTRONICS N.V.
    Inventors: Timothy F. Nordgren, Tracy C. Brechbiel, John Douglas Fraser
  • Publication number: 20110256503
    Abstract: The appliance includes an appliance body (12) as well as a system for producing microbubbles (20) and a system for producing an ultrasound signal beam (22) in a frequency range which activates at least some of the microbubbles. The appliance includes at least one of the following: (a) an array of ultrasound transducer elements (40) which produce a plurality of ultrasound signal beams; (b) an amplitude modulation assembly (51) for modulating the amplitude of the ultrasound signal; and (c) a frequency modulation system (61) for changing the frequency of the ultrasound signals over a selected range, to impact a range of microbubble sizes.
    Type: Application
    Filed: December 9, 2009
    Publication date: October 20, 2011
    Applicant: KONINKLIJKE PHILIPS ELECTRONICS N.V.
    Inventor: John Douglas Fraser
  • Publication number: 20110076638
    Abstract: The apparatus includes a source of gas (air) bubbles (14) in a liquid medium, the gas bubbles having a size range which is associated with the size of bacteria alone or in colonies, on teeth or other surfaces. A source of ultrasound signals (16, 18) has a range of frequencies between 200 kHz and 2 MHz, the ultrasound frequency range including the resonance frequencies of a majority of the bubbles. The application of the ultrasound to the bubble/liquid stream directed toward the biofilm on the teeth results in a dislodging/removal of the biofilm.
    Type: Application
    Filed: October 1, 2008
    Publication date: March 31, 2011
    Applicant: KONINKLIJKE PHILIPS ELECTRONICS N.V.
    Inventors: Bart Gottenbos, John Douglas Fraser, Jozef Johannes Maria Janssen, Benjamin Marty
  • Publication number: 20110040189
    Abstract: A capacitive ultrasound transducer capable of operation in collapsed mode either with a reduced bias voltage, or with no bias voltage, is provided. The transducer includes a substrate that is contoured so that a middle region of the flexible membrane is collapsed against the substrate in the absence of a bias voltage. A non-collapsible gap may exists between the substrate and peripheral regions of the flexible membrane. The contour of the substrate may be such as to strain the flexible membrane past the point of collapse, or to mechanically interfere with the flexible membrane. The substrate may include a further membrane disposed beneath the flexible membrane, the further membrane being contoured so that the flexible membrane is collapsed against it. The substrate may a support disposed beneath the further membrane to deflect a corresponding portion of the further membrane upward toward the flexible membrane. The support may be a post.
    Type: Application
    Filed: December 12, 2008
    Publication date: February 17, 2011
    Applicant: KONINKLIJKE PHILIPS ELECTRONICS N.V.
    Inventors: John Petruzzello, John Douglas Fraser, Shiwei Zhou, Benoit Dufort, Theodore James Letavic
  • Publication number: 20100202254
    Abstract: A capacitive ultrasound transducer includes a first electrode, a second electrode, and a third electrode, the third electrode including a central region disposed in collapsibly spaced relation with the first electrode, and a peripheral region disposed outward of the central region and disposed in collapsibly spaced relation with the second electrode. The transducer further includes a layer of a high dielectric constant material disposed between the third electrode and the first electrode, and between the third electrode and the second electrode. The transducer may be operable in a collapsed mode wherein the peripheral region of the third electrode oscillates relative to the second electrode, and the central region of the third electrode is fully collapsed with respect to the first electrode such that the dielectric layer is sandwiched therebetween. Piezoelectric actuation, such as d31 and d33 mode piezoelectric actuation, may further be included.
    Type: Application
    Filed: July 31, 2008
    Publication date: August 12, 2010
    Applicant: KONINKLIJKE PHILIPS ELECTRONICS N.V.
    Inventors: Aarnoud Laurens Roest, Klaus Reimann, Mareike Klee, Jozef Thomas Martinus Van Beek, John Douglas Fraser
  • Patent number: 6632178
    Abstract: An ultrasonic transducer is formed by a plurality of cMUT cells, each comprising a charged diaphragm plate capacitively opposing an oppositely charged base plate. The cMUT cells can be fabricated by conventional semiconductor processes and hence integrated with ancillary transducer circuitry such as a bias charge regulator. The cMUT cells can also be fabricated by micro-stereolithography whereby the cells can be formed using a variety of polymers and other materials.
    Type: Grant
    Filed: October 27, 2000
    Date of Patent: October 14, 2003
    Assignee: Koninklijke Philips Electronics N.V.
    Inventor: John Douglas Fraser
  • Patent number: 6469422
    Abstract: A two dimensional ultrasonic transducer array suitable for three dimensional phased array scanning is formed of hexagonally close packed transducer elements. In a preferred embodiment the transducer elements have a rectilinear shape, allowing the array to be fabricated with conventional dicing saw processes.
    Type: Grant
    Filed: January 30, 2002
    Date of Patent: October 22, 2002
    Assignee: Koninklijke Philips Ultrasound N.V.
    Inventor: John Douglas Fraser
  • Publication number: 20020130591
    Abstract: A two dimensional ultrasonic transducer array suitable for three dimensional phased array scanning is formed of hexagonally close packed transducer elements. In a preferred embodiment the transducer elements have a rectilinear shape, allowing the array to be fabricated with conventional dicing saw processes.
    Type: Application
    Filed: January 30, 2002
    Publication date: September 19, 2002
    Inventor: John Douglas Fraser
  • Patent number: 6443901
    Abstract: An ultrasonic transducer is formed by a plurality of cMUT cells, each comprising a charged diaphragm plate capacitively opposing an oppositely charged base plate. The diaphragm plate is distended toward the base plate by a bias charge. The base plate includes a central portion elevated toward the center of the diaphragm plate to cause the charge of the cell to be of maximum density at the moving center of the diaphragm plate. For harmonic operation the drive pulses applied to the cells are predistorted in consideration of the nonlinear operation of the device to reduce contamination of the transmit signal at the harmonic band. The cMUT cells can be fabricated by conventional semiconductor processes and hence integrated with ancillary transducer circuitry such as a bias charge regulator. The cMUT cells can also be fabricated by micro-stereolithography whereby the cells can be formed using a variety of polymers and other materials.
    Type: Grant
    Filed: June 15, 2000
    Date of Patent: September 3, 2002
    Assignee: Koninklijke Philips Electronics N.V.
    Inventor: John Douglas Fraser
  • Patent number: 6384516
    Abstract: A two dimensional ultrasonic transducer array suitable for three dimensional phased array scanning is formed of hexagonally close packed transducer elements. In a preferred embodiment the transducer elements have a rectilinear shape, allowing the array to be fabricated with conventional dicing saw processes.
    Type: Grant
    Filed: January 21, 2000
    Date of Patent: May 7, 2002
    Assignee: ATL Ultrasound, Inc.
    Inventor: John Douglas Fraser
  • Patent number: 6328696
    Abstract: An ultrasonic transducer is formed by a plurality of cMUT cells, each comprising a charged diaphragm plate capacitively opposing an oppositely charged base plate. A feedback controlled bias charge regulator controls the bias charge of the capacitive plates. The cMUT cells can be fabricated by conventional semiconductor processes and hence integrated with ancillary transducer circuitry such as the bias charge regulator.
    Type: Grant
    Filed: October 27, 2000
    Date of Patent: December 11, 2001
    Assignee: ATL Ultrasound, Inc.
    Inventor: John Douglas Fraser
  • Patent number: 6328697
    Abstract: An ultrasonic transducer is formed by a plurality of cMUT cells, each has a charged diaphragm plate capacitively opposing an oppositely charged base plate. The diaphragm plate is distended toward the base plate by a bias charge. The base plate includes a central portion elevated toward the center of the diaphragm plate to cause the charge of the cell to be of maximum density at the moving center of the diaphragm plate.
    Type: Grant
    Filed: October 27, 2000
    Date of Patent: December 11, 2001
    Assignee: ATL Ultrasound, Inc.
    Inventor: John Douglas Fraser