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:
May. 03, 2011
Filed:
Jul. 07, 2008
Kerry Cheung, Cambridge, MA (US);
Luis F. Velásquez-garcía, Boston, MA (US);
Akintunde I. Akinwande, Newton, MA (US);
Kerry Cheung, Cambridge, MA (US);
Luis F. Velásquez-García, Boston, MA (US);
Akintunde I. Akinwande, Newton, MA (US);
Massachusetts Institute of Technology, Cambridge, MA (US);
Abstract
A quadrupole mass filter (QMF) is provided. The QMF includes a plurality of rectangular shaped electrodes aligned in a symmetric manner to generate a quadrupole field. An aperture region is positioned in a center region parallel to and adjacent to each of the rectangular shaped electrodes. An incoming ion stream enters the aperture region so as to be controlled by the quadrupole field. A plurality of voltage sources provide a r.f. and d.c. signal to the electrodes for generating the quadrupole field. An auxiliary voltage source applies an auxiliary drive signal to the r.f. and d.c. signal to create new stability boundaries within the standard Mathieu stability regions with high-resolution around operating conditions where there are approximately no higher-order resonances.