Patent ID: 7142286

Claim:
A lithographic apparatus, comprising: an illumination system that supplies a beam of radiation; an array of individually controllable elements that pattern the beam; and a projection system that projects the patterned beam onto a target portion of a substrate, the projection system defining a pupil and comprising an array of lenses, wherein the array of lenses is arranged to direct a respective part of the patterned beam towards a respective part of the target portion of the substrate, wherein the individually controllable elements are selectively controllable to progressively direct a respective part of the patterned beam away from the pupil, such that a amount of the patterned beam passing through the pupil is progressively varied, wherein the individually controllable elements are arranged in groups, such that the patterned beam is directed by each element in each group towards a same lens in the lens array, and wherein the individually controllable elements in each group are controlled together to direct the patterned beam in different directions away from the pupil, such that a pattern imparted onto the beam by that group of individually controllable elements is substantially symmetrical with respect to the pupil.