Chapter/Index: Introduction | A | B | C | D | E | F | G | H | I | J | K | L | M | N | O | P | Q | R | S | T | U | V | W | X | Y | Z | Appendix
| Magnetic lenses with short focal lengths are obtained by concentrating the magnetic field by means of magnetic polepieces. Glaser’s famous bell-shaped model suggested that in order to attain the minimum focal length and the minimum aberrations of a magnetic lens used in a TEM the specimen should be put at the middle of the gap of a pair of symmetrical polepieces [1], e.g. called objective polepiece.
[1] Cosslett, V. E. 1991. Fifty years of instrumental development of the electron microscope, in Advances in Optical and Electron Microscopy, Barer, R. and Cosslett, V. E. Eds., Academic Press, London, 215–267.
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