Multiple electron lens

摘要

A multiple electron lens having two axially spaced polepieces defining a space therebetween. The polepieces each have a plurality of axial through openings aligned coaxially defining electron beam paths. A sole anode plate is disposed axially spaced from the polepieces and has openings aligned with the openings defining the beam paths and equal in number thereto. Each beam path has an auxiliary exciting coil and a corresponding stigmator coaxially arranged with the related beam path within the space defined between the polepieces.