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:
Nov. 01, 2011
Filed:
Jan. 12, 2010
Angus Bewick, Abindon, GB;
Angus Bewick, Abindon, GB;
Oxford Instruments Nanotechnology Tools Limited, London, GB;
Abstract
A charged particle filter comprises a magnetic deflector and an outer shield. The magnetic deflector has a bore along an axis thereof passing through the deflector from a specimen end to a detector end of the deflector and through which charged particles pass when in use. The deflector is formed from one or more magnets positioned around the bore in a Halbach configuration thereby generating a relatively high magnetic field strength within the bore and a relatively low magnetic field strength outside of the deflector. The deflector has a geometry defining an outer surface and an inner surface, wherein each of the outer and inner surfaces of the deflector taper towards the axis as a respective function of distance in the specimen direction along the axis. The outer shield is formed from a soft magnetic material surrounding the magnet deflector on an outer surface side of the deflector and having a projecting portion which extends in the specimen direction with respect to the magnetic deflector from the specimen end of the deflector.