| 摘要 |
A composite optical apparatus (40) includes a series of electrostatic units (41) arranged along an optical column axis (z), each unit being an arrangement of electrically insulated electrodes (E1-En) arranged on a common plane around an optical column axis (z), each electrode (E1-En) having an electrical connection for receiving a voltage that combines with other electrode voltages (V1-Vn) in the series of electrostatic units (41) to produce a continuous and controllable three-dimensional potential distribution (U3) within any one of the optical structures (40) that is variable along the optical column axis (z) and that reduces aberrations. The composite optical apparatus (40) may be placed in an optical column as an electrostatic deflector (L1), as a focusing electrostatic lens (L2, L3) or any combination of them. The composite optical structure (40) enables scientific determination of an optimized potential distribution within the optical structure for minimizing focusing or deflection aberrations of electron or ion beams in an optical column. The method concerns a synthesis approach for minimizing aberrations in optical columns using the composite optical apparatus (40) in various industrial applications requiring the use of optical columns provided with electron or ion beams. |
