The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Mar. 31, 1998
Filed:
Apr. 30, 1996
Applicant:
Inventor:
Jerry T Dowell, Portola Valley, CA (US);
Assignee:
Hewlett Packard Company, Palo Alto, CA (US);
Attorney:
Primary Examiner:
Int. Cl.
CPC ...
H01J / ;
U.S. Cl.
CPC ...
250292 ; 250282 ;
Abstract
Selective trapping of ions from an external source into a quadrupole trap is accomplished by applying a parametric pump voltage to the quadrupole trap electrodes in such a phase as to extract energy from the ions, causing the ions to accumulate in the center of the trap. Pump voltage phase is controlled by the timing of the injection of ions into the trap relative to the absolute phase of the pump voltage. Optimum phasing results when the ion packet allowed into the trap through gating of the ion beam optics is sufficiently opposed by the field produced by the parametric pump voltage. The ions are also subjected to a normal RF trapping field.