Chromatic aberration electron monochromator

The performance of an electron monochromator based on the chromatic aberration of electrostatic lenses was investigated. A first approximation analysis of the monochromator’s operation is given. A prototype monochromator was built and tested to produce an electron beam of less than 25 MeV FWHM at 10−9A, with high stability and reproducibility. Design and operating details are given.