Chromatic aberration corrector for charged particles and charged-particle optical apparatus using the corrector

摘要

The present invention provides an aberration corrector functioning under a condition outside the setting optical condition of an incorporated charged particle beam apparatus. An intermediate potential region different from the ground potential of an aberration corrector is provided in the space between the stages of multipole lenses constructing the aberration corrector to adjust a potential. Using this, when selecting an incident (outgoing) condition, an outgoing (incident) condition can be adjusted.