Charged particle apparatus and method

A method of operating a charged particle beam apparatus comprising:

• a source array comprising charged particle emitters configured to emit a charged particle beam a plurality in an array of charged particle beams;
• and an array of charged particle-optical columns comprising a plurality of charged particle-optical columns arranged in an charged particle-optical column array, the plurality of charged particle-optical columns configured to project respective charged particle beams from the source array towards a sample and comprising an objective lens configured to direct the charged particle beam towards the sample, the objective lens being an electrostatic objective lens, the objective lenses being comprised in an objective lens array, wherein the method comprises:
• selecting a subset of charged particle emitters from the source array to emit the charged particle beams;
• and
• projecting the charged particle beams emitted by the subset of charged particle emitters towards the sample.

A charged particle beam apparatus configured to project charged particle beams towards a sample, wherein the charged particle beam apparatus comprises:

• a plurality of charged particle-optical columns configured to project respective charged particle beams towards the sample, wherein each charged particle-optical column comprises:
• a charged particle emitter configured to emit the charged particle beam towards the sample, the charged particle emitters being comprised in a source array;
• an objective lens comprising an electrostatic electrode configured to direct the charged particle beam towards the sample, the objective lenses being comprised in an objective lens array, the electrostatic electrode being common to a plurality of the charged particle-optical columns;
• and
• a detector associated with the objective lens array, configured to detect signal charged particles emitted from the sample,
• wherein the objective lens is the most down-beam element of the charged particle-optical column configured to affect the charged particle beam directed towards the sample.