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:
Sep. 30, 1997
Filed:
Dec. 18, 1995
Curt A Flory, Los Altos, CA (US);
Stuart C Hansen, Palo Alto, CA (US);
Carl Myerholtz, Cupertino, CA (US);
Hewlett Packard Company, Palo Alto, CA (US);
Abstract
A notch filter for selectively removing a target ion with a specific mass-to-charge ratio from an ion beam is provided. The notch filter uses a quadrupole and a power supply for generating an rf electrical potential in the quadrupole. The quadrupole has two pairs of parallel electrodes of opposite polarities. Each pair is comprised of two parallel electrodes having equal electrical potential. The rf electrical potential generated by the power supply is a superposition of an rf quadrupole frequency component and an excision frequency component. The quadrupole has an inlet end and an outlet end and the ion beam traverses from the inlet end to the outlet end. As a result of the rf quadrupole frequency component, ions of above a selected mass-to-charge ratio are guided down the quadrupole. The excision frequency component, which is at the second harmonic of the dominant resonant frequency of the target ion, causes the target ion to resonate and be removed from the ion beam before exiting the quadrupole.