Design and Fabrication of the Single Polepiece Magnetic Electron Lens of Truncated Cone Polepiece Shape

Abstract

AbstractThe magnetic electron objective lens is of a great importance which limit the resolving power of the electron microscope.The present work investigates the objective focal properties of a single polepiece magnetic electron lens of truncated cone polepiece shape of the selected geometrical dimensions for practical applications. The lens has been fabricated consist of cast shield made of mild steel combined with exciting isolated cooper coil of 500 turns.The theoretical and experimental results presented the magnetic flux density distribution and the objective focal properties of the lens, in mode of operation when the direction of incident electrons beam facing the lens back plate of the lens.Moreover, the theoretical and experimental results are in a good agreements.Keywords: electron optics, magnetic lens fabrication, design of magnetic lens, objective properties, low voltage scanning electron microscope.