Apparatus and method for shaping and detecting a particle beam

US5270542A · kind A · utility

Assignee

• Regents of the University of Minnesota · US

Inventors

• Peter H. McMurry · Minneapolis, US
• David B. Kittelson · Minneapolis, US
• Paul Ziemann · Radolfzell, DE
• Peng Liu · Beijing, CN
• Nagaraja Rao · Boca Raton, US

Key dates

• Filing date: Dec 31, 1992
• Grant date: Dec 14, 1993
• Expiry date: Dec 31, 2012

Classification

• Technology area (CPC G): Physics
• CPC primary: G01N30/7293
• WIPO field: Measurement
• WIPO sector: Instruments

Abstract

A particle beam shaping apparatus preferably includes a prefocusing element and a primary focusing element disposed within a tube. An aerosol beam source having relatively heavy particles and relatively light gas is operably connected to the prefocusing element. The prefocusing element preferentially expands the aerosol beam such that the gas diverges laterally relatively rapidly while the particles diverge laterally relatively slowly. The tube laterally confines the rapidly expanding gas such that the primary focusing element converges the gas upon the particle beam to more narrow the particle beam. A detector may be located downstream of the primary focusing means to sense the particles impinging thereon. A skimmer is preferably interposed between the primary focusing element and the detection means to remove the gas while allowing the particles to pass therethrough. The particles may be electrically charged and deflected prior to their detection such that the particles' relative masses may be determined by the detection means.