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Elements of a Transmission Electron Microscope

  • Ludwig Reimer
Chapter
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Part of the Springer Series in Optical Sciences book series (SSOS, volume 36)

Abstract

The gun of an electron microscope does not only emit electrons into the vacuum and accelerate them between cathode and anode, but is also required to produce an electron beam of high brightness and high temporal and spatial coherence. The conventional thermionic emission from a tungsten wire is limited in temporal coherence by an energy broadening of the emitted electrons of the order of a few electronvolts and in spatial coherence by the gun brightness. Lanthanum hexaboride and field-emission cathodes are alternatives, for which the energy broadening is less and the gun brightness higher.

Keywords

Objective Lens Scan Transmission Electron Microscopy Objective Aperture Condenser Lens Cathode Temperature 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.

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Copyright information

© Springer-Verlag Berlin Heidelberg 1984

Authors and Affiliations

  • Ludwig Reimer
    • 1
  1. 1.Physikalisches InstitutWestfälische Wilhelms-Universität MünsterMünsterFed. Rep. of Germany

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