ABSTRACT
Electrostatic lenses are widely used as transport lens systems in the spectrometry of electron or ion beams as well as in ion beam optical systems. Evaluation of the properties of electrostatic lenses can usually be separated into two parts, the derivation of the potential distribution followed by the calculation of the electron optical properties, mostly by using only the potential along the optic axis. The main obstacle in the design of high performance electrostatic lenses is caused by problems connected with electrical insulation and voltage breakdown. The simplest equivalents of cylindrical lenses in optics are electrostatic lenses of planar symmetry where the potential is independent of one of the coordinates perpendicular to the beam axis. Most of the optimizations of electrostatic lenses and systems have been achieved by systematic investigation by establishing the dependence of the optical properties on geometric or electrical variables.
