Enhanced integrity projection lens assembly

Projection lens assembly for directing a multitude of charged particle beamlets onto an image plane, said projection lens assembly comprising:

• a beam stop array comprising an array of apertures, for blocking charged particle beamlets provided with a blanking deflection by a beam blanker and letting through charged particle beamlets not provided with a blanking deflection by said beam blanker,
• at least one support element comprising a through-opening for allowing the multitude of charged particle beamlets to pass through,
• a first electrode and a second electrode, said first electrode and second electrode supported by said at least one support element, wherein the first and second electrode are arranged in or near a plane defined by a downstream distal edge of he projection lens assembly, hole-array aligned with the through-opening for allowing charged particle beamlets to pass through,
• said projection lens assembly further comprising:
• a deflector unit arranged upstream from said first and second electrode and downstream from said beam blanker,
• an annular body comprising a conductive circumferential wall,
• wherein the annular body and the support element are electrically connected and set substantially at ground potential.