Actuator for a lithographic apparatus

Abstract

An actuator comprising a first magnetic assembly attached to a long stroke module and comprising at least two first permanent magnets, a second magnetic assembly attached to a short stroke module and comprising at least one second permanent magnet. The first and second magnetic assemblies are configured to support the short stroke module with respect to the long stroke module in a first direction. The second magnetic assembly is located between the first permanent magnets. The actuator includes an electrically conductive element connectable to a power supply. The first magnetic assembly is longer than the second magnetic assembly in a second direction to enable relative displacement of the short stroke module and the long stroke module and the first magnetic assembly is geometrically configured such that a substantially homogeneous parallel magnetic field is provided.

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