The Investigation of True and a Focal Zoom-Lens Properties of Five-Element Cylindrical Electrostatic Lens

In the present work , a computational investigation has been considered on the true and a focal zoom-lens (i.e. lenses whose magnification may be changed without losing focus)for the five-cylindrical electrostatic lens system, by the aid of the simulation program LENSYS, using the finite difference method .Results are obtained as a function of the ratio of the controlling voltages. It was found that the five-cylindrical lens can be operated with the whole focus properties in a useful mode for controlling and focusing the charged particles in experimental studies.