On the Chromatic Field Aberration of the Magnetic Electron Lens in the Electron Microscope

摘要

The chromatic field aberration of the magnetic lens in the electron microscope is theoretically studied. Good results are obtained for the coefficient of the chromatic difference in magnification of the objective, taking into account the inclination of the principal illuminating rays. The same coefficient of the intermediate lens increases rapidly as the magnification is reduced by the intermediate lens. The calculated results agree well with experimental results. Calculated results are given for the coefficients of chromatic difference in rotation of all lenses as well as for the coefficient of chromatic difference in magnification of the projection lens.