Patents by Inventor Ludger Freisen

Ludger Freisen 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: 5396174
    Abstract: The conductor structures of an antenna in a nuclear magnetic resonance tomography apparatus are covered with lamellae that extend in longitudinal direction of the examination space and have large-area connections at the end sides of the antenna to a shielding that surrounds the examination space. In an alternative embodiment, the lamellae extend the azimuthal direction and are connected to a shielding (3) surrounding the examination space at the respective longitudinal edges of the conductor structure of the antenna via broad-web, planar conductors with a free cross section remaining between the conductors.
    Type: Grant
    Filed: December 28, 1993
    Date of Patent: March 7, 1995
    Assignee: Siemens Aktiengesellschaft
    Inventors: Wilhelm Hanke, Michael Morita, Ludger Freisen, deceased
  • Patent number: 4701710
    Abstract: For the representation of images of regions selected from the interior of an examination subject, coils are provided for the application of a primary magnetic field and of magnetic gradient fields to the examination subject. An electrical conductor configuration detects the deflection of the atomic nuclei of the examination subject from their position of equilibrium as a result of high frequency magnetic excitation pulses. The configuration is formed by two interspersed individual conductor configurations adapted for respective different measurement frequencies. Each configuration comprises parallel conductors connected at their ends and arranged in spaced relation to an electrically grounded surface to form a transmission line configuration resonant at a respective one of the measurement frequencies.
    Type: Grant
    Filed: May 22, 1985
    Date of Patent: October 20, 1987
    Assignee: Siemens Aktiengesellschaft
    Inventors: Ludger Freisen, Helmut Kess, Norbert Krause, Ralph Meissner