Patents by Inventor Douglas Karl Johnson

Douglas Karl Johnson 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: 8442619
    Abstract: A system and method for identifying errors while tracking instrument navigations is enclosed. The method may include assigning a plurality of virtual points to a plurality of sensors. At least one of the virtual points may be a non-fixed virtual point. The assignment of virtual points to sensors may be determined based on the medical instrument, or the medical instrument attachment, being used. Virtual point locations may be determined for the non-fixed virtual point. The locations of the non-fixed virtual point may be determined based on the medical instrument, or the medical instrument attachment, being used. The vector values for vectors terminating at the non-fixed virtual point may be adjusted. The field integrity values for the virtual points may be computed. If a field integrity value is greater than a threshold value, an error signal may be communicated.
    Type: Grant
    Filed: August 30, 2006
    Date of Patent: May 14, 2013
    Assignee: General Electric Company
    Inventors: Dun Alex Li, Joseph Casey Crager, Douglas Karl Johnson
  • Publication number: 20080121703
    Abstract: A system and method for identifying errors while tracking instrument navigations is enclosed. The method may include assigning a plurality of virtual points to a plurality of sensors. At least one of the virtual points may be a non-fixed virtual point. The assignment of virtual points to sensors may be determined based on the medical instrument, or the medical instrument attachment, being used. Virtual point locations may be determined for the non-fixed virtual point. The locations of the non-fixed virtual point may be determined based on the medical instrument, or the medical instrument attachment, being used. The vector values for vectors terminating at the non-fixed virtual point may be adjusted. The field integrity values for the virtual points may be computed. If a field integrity value is greater than a threshold value, an error signal may be communicated.
    Type: Application
    Filed: August 30, 2006
    Publication date: May 29, 2008
    Inventors: Dun Alex Li, Joseph Casey Crager, Douglas Karl Johnson
  • Patent number: 7097357
    Abstract: Certain embodiments of the present invention provide a method and system for improved registration of image and navigation references used in image-guided operations. Certain embodiments of the system include an image acquisition device for obtaining at least one image of an object, a first calibration fixture positioned in relation to the image acquisition device, and a second calibration fixture positioned in relation to the object. The position data from first calibration fixture is used to form a characterization of the image acquisition device, which is corrected by position data from the second calibration fixture. In an embodiment, a first calibration fixture is affixed to a C-arm camera and a smaller second calibration fixture is affixed to a patient. Data from the first and second calibration fixtures is used with tracking data to calibrate the image acquisition data and register reference points in image and navigation reference frames.
    Type: Grant
    Filed: June 2, 2004
    Date of Patent: August 29, 2006
    Assignee: General Electric Company
    Inventors: Douglas Karl Johnson, Lewis J. Levine