Electrostatic Strong-Focusing Lens

Abstract

The basic principles of an electrostatic strong-focusing lens are described in order to illustrate a modern application of several classical concepts. The motion of an ion in the electrostatic field is described in terms of optical analogies to thick lenses. The astigmatism of such lenses is discussed, and the two-section lens designed for use with the Naval Research Laboratory 5-Mev Van de Graaff proton beam is described.