Patents by Inventor D.J. Douglas

D.J. Douglas 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).

  • Method and apparatus for providing two-dimensional substantially quadrupole fields having selected hexapole components
    Publication number: 20050067564
    Abstract: A method and apparatus for manipulating ions using a two-dimensional substantially quadrupole field, and a method of manufacturing and operating an apparatus for manipulating ions using a two-dimensional substantially quadrupole field are described. The field has a quadrupole harmonic with amplitude A2 and a hexapole harmonic with amplitude A3. The amplitude A3 of the hexapole component of the field is selected to improve the performance of the field with respect to ion selection and ion fragmentation.
    Type: Application
    Filed: September 17, 2004
    Publication date: March 31, 2005
    Applicant: The University of British Columbia
    Inventors: D.J. Douglas, Chuan-Fan Ding, Frank Londry