Patents by Inventor Chun F. Chan

Chun F. Chan 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).

  • Negative ion beam injection apparatus with magnetic shield and electron removal means
    Patent number: 5365070
    Abstract: A negative ion source is constructed to produce H.sup.- ions without using Cesium. A high percentage of secondary electrons that typically accompany the extracted H.sup.- are trapped and eliminated from the beam by permanent magnets in the initial stage of acceleration. Penetration of the magnetic field from the permanent magnets into the ion source is minimized. This reduces the destructive effect the magnetic field could have on negative ion production and extraction from the source. A beam expansion section in the extractor results in a strongly converged final beam.
    Type: Grant
    Filed: April 29, 1992
    Date of Patent: November 15, 1994
    Assignee: The Regents of the University of California
    Inventors: Oscar A. Anderson, Chun F. Chan, Ka-Ngo Leung