Comparison between Two Types of Electrodes for Electrostatic Quadrupole Lens

Abstract

This work aims to find the optimum design of electrostatic quadrupole lens and make the comparison between two different electrodes shapes which are computed with the aid of transfer matrices. Two types of electrostatic quadrupole lens, cylindrical convex electrodes, and cylindrical concave electrodes were used to find optimum field model, which was close to the field distribution for each design of the proposed lens. The path of charge-particles beam is traverse the field model has been determined by solving the trajectory equation of motion in Cartesian coordinates. Then, take the comparison of the optimum values of spherical aberration coefficients and resolution limits in both convergence and divergence plans for each proposed type.