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:
Apr. 01, 1997
Filed:
Oct. 04, 1995
Erich Plies, Tuebingen, DE;
Siemens Aktiengesellschaft, Munich, DE;
Abstract
Purely electrical or magnetic deflection systems are usually utilized in the probe-shaping part of modern electron beam tomographs in order to remove the gas ions generated in the evacuated drift tube by electron impact from the beam. The known deflection systems, however, cause an offset of the electron beam, so that this enters extra-axially into the lens element following the deflection system. In the apparatus for removing ions from an electron beam disclosed herein, a deflection unit (Wien filter) generates an E.times.B field oriented perpendicular to the beam axis that exerts strong shearing forces only on the positively charged gas ions, but does not influence the electrons. The deflection unit is essentially composed of two tube electrodes lying at a constant potential, of an electrostatic octopole deflector, and two saddle coil pairs annularly surrounding the octopole deflector. The apparatus is useful for fast electron beam tomographs, including x-ray scanners.