Patent ID: 7667822

Claim:
A lithographic apparatus comprising: a radiation system configured to condition a beam of radiation; a support constructed to support a patterning device, the patterning device being capable of imparting the radiation beam with a pattern in its cross-section to form a patterned radiation beam, the support comprising a force actuator device to exert a force onto the patterning device in a direction of movement of the support, the force actuator device comprising: (i) a movable part that is pivotable about a pivot axis connected to the support, the movable part being substantially balanced with respect to the pivot axis in the direction of movement of the support, and (ii) an actuator to exert the force onto the patterning device via the movable part; a controller to drive the actuator based on an acceleration of the support in the direction of movement; a projection system configured to project the patterned beam of radiation onto a substrate; and a substrate table configured to support the substrate, wherein the actuator is configured to remain in a substantially rest state when the support accelerates, from a position where the support is at rest, in a direction that is opposite to said direction of movement.