DEVICE FOR SEALING A PROJECTION ILLUMINATION SYSTEM

摘要

The invention relates to a projection illumination system (1) consisting of an illumination arrangement (3), a reticle (5), a projection lens (7) and an imaging plane. Open spaces are provided in the surrounding area between the individual elements. A gas distributor (8,8'), which is cross-flown by an inert gas or nitrogen, is disposed in at least one of said open spaces. The shape and size of the gas distributor (8,8') are selected in such a way that one or several open spaces are sealed in an at least substantial manner in relation to area surrounding the projection illumination system (1).