Patent ID: 7304718

Claim:
A lithographic apparatus, comprising: an illumination system that supplies a beam of radiation; an array of reflectors that pattern the beam, each reflector having an associated actuator that positions the reflector, and the array of reflectors having a plurality of control areas that each comprise a plurality of rows of the reflectors; a controller that provides control signals to the control areas, such that, on the basis of said control signals, alternate rows of reflectors in each of the plurality of control areas are set to a first common position and the remaining rows of reflectors in the plurality of control areas are set to a second common position, wherein for any given control area, said control signals control said given control area, without controlling any single reflector in said given control area independently of remaining reflectors in said given control area, and said first and second common positions are designated by said control signals from among three or more possible positions that correspond to a sequence of gray states; and a projection system that projects the patterned beam onto a target portion of a substrate.