Patents by Inventor Douglas J. Thomson

Douglas J. Thomson 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: 10281511
    Abstract: A new passive wireless electric field sensor is disclosed. This sensor does not require direct attachment to a source of power which makes it passive. It is composed of a resonator loaded with varactors. The sensor is interrogated by a remotely located device transmitting and receiving the pulses of sine wave in the resonance frequency range of the sensor. Therefore, the sensor can be mounted in the vicinity of high voltage apparatus and interrogated from a safe distance.
    Type: Grant
    Filed: November 13, 2015
    Date of Patent: May 7, 2019
    Assignee: The University of Manitoba
    Inventors: Mana Yazdani, Behzad Kordi, Douglas J. Thomson
  • Publication number: 20170322246
    Abstract: A new passive wireless electric field sensor is disclosed. This sensor does not require direct attachment to a source of power which makes it passive. It is composed of a resonator loaded with varactors. The sensor is interrogated by a remotely located device transmitting and receiving the pulses of sine wave in the resonance frequency range of the sensor. Therefore, the sensor can be mounted in the vicinity of high voltage apparatus and interrogated from a safe distance.
    Type: Application
    Filed: November 13, 2015
    Publication date: November 9, 2017
    Inventors: Mana Yazdani, Behzad Kordi, Douglas J. Thomson
  • Publication number: 20100301321
    Abstract: Tunable diodes and methods of making.
    Type: Application
    Filed: May 28, 2010
    Publication date: December 2, 2010
    Inventors: Michael S. Freund, Jun Hui Zhao, G.M. Aminur Rahman, Douglas J. Thomson
  • Patent number: 6377066
    Abstract: A sub-micron probe apparatus to be added to an existing probe station. In one embodiment, the probe apparatus includes a course positioning unit to be optionally mounted or added to an existing probe station platform. A fine positioning unit is attached to an arm attached to the course positioning unit. A cantilever having a tip is attached to a support structure attached to the fine positioning unit. The course and fine positioning units are used to place the cantilever and tip over a surface of a device under test (DUT). Motion of the cantilever is detected with a motion sensor. An image of the surface of the DUT may be obtained. In addition, an electrical signal carried in an electrical trace on or near the surface of the DUT can be detected. An electrical signal may also be supplied to the electrical trace on or near the surface of the DUT. The field of vision of an optical imager used to image the DUT at the probe area is not obstructed by the probe apparatus.
    Type: Grant
    Filed: July 5, 2000
    Date of Patent: April 23, 2002
    Assignee: MFI Technologies Corporation
    Inventors: Greg E. Bridges, Douglas J. Thomson
  • Patent number: 6298715
    Abstract: A scanning force microscope probe cantilever having a reflective structure. In one embodiment, the described scanning force microscope probe cantilever includes a reflective structure on the cantilever. In one embodiment, light is directed to the reflective structure on the cantilever in a direction having a directional component from a fixed end to a free end of the cantilever. In one embodiment, light is reflected from the reflective structure in a direction having a directional component from the free end to a fixed end of the cantilever.
    Type: Grant
    Filed: December 22, 1999
    Date of Patent: October 9, 2001
    Assignee: MFI Technologies Corporation
    Inventors: Douglas J. Thomson, Christopher O. Lada
  • Patent number: 5959447
    Abstract: A method and an apparatus for providing non-contact measurement of waveforms proximate to a surface of a sample. In one version, the describe apparatus includes a probe waveform generator that generates probe waveforms with the same repetition rate as a sample waveform to the measured from the sample. The apparatus includes a cantilever with a signal path to carry the probe waveform to a position above the sample surface where the sample waveform is to be measured. The apparatus of the present invention also includes a gate to periodically route the probe waveforms to the cantilever tip. The gate is controlled by a periodic gating signal with a period substantially longer than the signal period of the sample waveform. In one version, the gate is switched at a repetition rate substantially equal to a mechanical resonant repetition rate of the cantilever. Capacitive coupling between the cantilever and the signal line of the sample results in a periodic motion of the cantilever at the gating repetition rate.
    Type: Grant
    Filed: February 6, 1998
    Date of Patent: September 28, 1999
    Assignee: Micron Force Instruments, Inc.
    Inventors: Greg E. Bridges, Ra'a A. Said, Douglas J. Thomson
  • Patent number: 5402236
    Abstract: Displacement of an object from a sensor is detected using a fiber optic a discharge end of which is arranged adjacent to the space from the object. Light passing along the fiber optic is reflected at the discharge end and is also reflected by the object at a position spaced from the discharge end. These two reflected parts of the light interfere causing an interference pattern. The light path from the discharge end to the object is cyclically varied using a sinusoidal dither obtained either by physical movement or by electro-optical means. This allows the output from the photo diode detecting the return reflected light to be analyzed as an alternating signal varying over time rather than as a simple comparison of absolute values as is used in the conventional techniques.
    Type: Grant
    Filed: March 18, 1993
    Date of Patent: March 28, 1995
    Assignee: Iders Incorporated
    Inventors: Bradley Brown, Douglas J. Thomson
  • Patent number: 5332973
    Abstract: Built-in current mode quiescent current monitoring circuitry is provided for measuring a circuit's or a subcircuit's quiescent current. Anomalously high quiescent current (Iddq) generally results as a consequence of a manufacturing defect. These defects include those not detected by tests generated using traditional fault models. The technique provided here is based upon generating a proportionally matched current to the circuit under test current by a control loop. The proportionally matched current is then sent to a comparator where it is compared to a reference current, the reference current representing an acceptable quiescent current level. The output of the comparator then indicates whether the quiescent current is above or below the reference current.
    Type: Grant
    Filed: May 1, 1992
    Date of Patent: July 26, 1994
    Assignee: The University of Manitoba
    Inventors: Bradley D. Brown, Robert D. McLeod, Douglas J. Thomson