Accurate determination of magnification in the electron microscope

Abstract

The magnification of the Siemens Elmiskop I at about 57,000 times can be determined with an accuracy of better than 1% for any object plane position and any region in the final image. This is achieved by taking into account magnification variations due to hysteresis effects in the lenses, changes in the accelerating voltage, changes in object plane position, and distortion produced by the projector lens.