Patent ID: 7312852

Claim:
A lithographic apparatus, comprising: an illumination system configured to condition a radiation beam; a support configured to support a patterning device, the patterning device being configured to impart the radiation beam with a pattern in its cross-section to form a patterned radiation beam; a substrate table configured to hold a substrate; and a projection system configured to project the patterned radiation beam onto a target portion of the substrate, wherein the lithographic apparatus comprises an optical element, the optical element comprising a half-wavelength plate having a first side and a second side, each of the first and second sides at an angle other than 90 degrees from a common third side and the optical element is configured to provide a first portion of the radiation beam with a linear polarization in a first direction, or to provide a first portion of the radiation beam with a linear polarization in the first direction and a second portion of the radiation beam with a linear polarization in a second direction, the second direction being perpendicular to the first direction.