Reconstructed Polepieces to the Objective Magnetic Lens Depending on Some Geometrical and Physical Parameters

Abstract

A function for the electron beam trajectory has been used in the present work with respect of a certain operation mode for path of the beams path, to synthesis the symmetrical objective magnetic lens. This function has six optimization parameters, which are respectively the action region (i.e. the air-gap), the height of electron beam trajectory, its gradient (the first derivatives) at the beginning and ending of the action region, and the length of lens. The influence of each of them is investigated concerning the objective focal properties. Indeed, the result obviously shows the effect of some of these parameters on the geometrical and physical properties to the synthesis magnetic lens, to specify the optimum symmetrical objective lens which desire, (i.e. the lens has the lowest aberration) to reconstruct its polepiece.

Keywords: Electron Optics, Synthesis, Objective Magnetic Lenses, Aberrations.