Patent ID: 8247782

Claim:
An apparatus, comprising: a. a charged particle source configured to emit charged particles; b. at least one particle optical element configured to form a charged particle beam of charged particles emitted by the charged particle source; c. an objective lens configured to generate a charged particle probe from the charged particle beam, the objective lens defining a particle optical axis; d. a first electrostatic deflection element arranged—in a direction of propagation of charged particles emitted by the charged particle source—downstream of the objective lens, the first electrostatic deflection element configured to deflect the charged particle beam in a direction perpendicular to the charged particle optical axis; and e. an electrically conductive shielding element with an opening configured so that the charged particle beam can pass through the opening, the electrically conductive shielding element being arranged—in the direction of propagation of charged particles emitted by the charged particle source—downstream of the first electrostatic deflection element.