تأثير زاوية القطب على الخواص البصرية للعدسة الكهروستاتيكية المغمورة

Abstract EN

Two models of an electrostatic immersion lenses of double electrodes have been designed of equal diameter and pole thickness, at different distances between their electrodes for the upper and lower parts.

Each model includes two lenses according to its electrode angle that varied.

The effect of the variation of the single electrode angle was studied for each lens on the optical properties at a constant voltage ratio.

An optimum electrode angle has been chosen for the lenses one with a lowest spherical and chromatic aberration coefficients in order to compared its optical properties at different voltages ratio at zero magnification condition.

It was found that the lenses E1and E3 are better than E2 and E4 in the two models.

Moreover, it was found that E3 has an optimum optical performance within the two models.

The results of the optical properties of the electrostatic lenses in the present work have been compared with those of the published results.

A great improvement in the optical performance of the considered lenses has been found.