Abstract: The present invention provides an ion-optics system for a source of ions for discharge into gases, the system comprising a screen grid (1) and an accelerator grid (2) constituted by respective frames (3, 4) and respective systems of parallel wires (5, 6) fixed to the frames by means of springs (21), the frames of the grids being assembled to each other via insulators (7) to which they are fixed, the system being provided with a displacement device (9) for adjusting the wires in each of the grids, which device comprising rolls (11) disposed transversely relative to the wires in each grid and offering guide elements (12) in which the wires are placed, the rolls being installed on the frames of the grids with the facility of rotating about their own axes and of changing position in three dimensions together with the wires.

Abstract: Apparatus comprises a vacuum chamber (1) accommodating a source (2) of ion flow directed toward the surface being machined, and a system (3) for decelerating ion flow. The system (3) includes a shielding electrode (5) positioned before the workpieces (4) and having a hole (7) for the passage of ion flow, and at least one decelerating electrode (6) electrically insulated from the walls of the vacuum chamber (1) and shielding electrode (5). The decelerating electrode (6) has the form of a magnetic element whose magnetization vector (M) is substantially congruent with the workpiece surface being machined. In addition, line (13) of electron drift current is closed in a direction transverse of the direction of the ion flow.