Apparatus and methods for adjusting beam condition of charged particles are disclosed. According to certain embodiments, the apparatus includes one or more first multipole lenses displaced above an aperture, the one or more first multipole lenses being configured to adjust a beam current of a charged-particle beam passing through the aperture. The apparatus also includes one or more second multipole lenses displaced below the aperture, the one or more second multipole lenses being configured to adjust at least one of a spot size and a spot shape of the beam.