Lithographic apparatus

摘要

A kit of parts for assembling an optical element for use in a lithographic apparatus comprises a large number of different small pieces which direct light into respective regions of the pupil plane of the radiation system and/or change the polarization state of incident radiation. The previously manufactured pieces are selected and assembled into an optical element to rapidly create a desired intensity distribution. The optical element may also be disassembled and the pieces reused. <IMAGE>