Patent ID: 7852460

Claim:
A reflector assembly for use in a lithographic projection apparatus, the reflector assembly comprising: a first and a second reflector extending in a direction of an optical axis, the first and second reflector each having a reflective surface, a backing surface and an entry section at respectively a first and a second distance from the optical axis, the first distance being larger than the second distance, rays deriving from a radiation source being cut off by the entry sections of the first and second reflectors and being reflected on the reflective surface of the first reflector and defining a high radiation intensity zone and a low radiation intensity zone between the reflectors; a radial support member configured to support the reflectors and extending through the first and second reflectors and the low radiation intensity zone, wherein the radial support member creates a shade in a downstream direction of the optical axis and a virtual shade in an upstream direction of the optical axis; and a structure placed in the virtual shade.