Original title:
Computations of Wien Filter Properties and Aberrations
Authors:
Lencová, Bohumila ; Vlček, Ivan Document type: Papers Conference/Event: EUREM /12./ - European Congress on Electron Microscopy, Brno (CZ), 2000-07-09 / 2000-07-14
Year:
2000
Language:
eng Abstract:
Wien filter is studied in electron optics as a separator in a LEEM or as a separator of primary and secondary beams in a low voltage SEM. The advantage of the Wien filter is that one beam is only slightly influenced by the filter and the second beam can easily be handled, the required separation angle for this is about 10-20 degrees. The computation of aberrations of the Wien filter needs to take into account field shapes of both strong dipole fields and the additional quadrupole, the action of the filter is then that of a weak lens and the aberation structure is more complicated than that of a rotationally symmetric lens. The determination of aberation coefficients from direct ray tracing for this optical element is often preferred to aberration theory. Project no.: CEZ:AV0Z2065902 (CEP), IAA1065804 (CEP) Funding provider: GA AV ČR Host item entry: Proceedings of the 12th European Congress on Electron Microscopy, ISBN 80-238-5503-4 Note: Související webová stránka: mailto:bohunka@isibrno.cz
Institution: Institute of Scientific Instruments AS ČR
(web)
Document availability information: Fulltext is available at the institute of the Academy of Sciences. Original record: http://hdl.handle.net/11104/0100858