A contamination prevention system is constructed and arranged to prevent
material from propagating with radiation into a lithographic apparatus.
The contamination prevention system includes a rotatable carrier provided
with a plurality of generally radially outwardly extending blades. The
blades are constructed and arranged to absorb or deflect the material.
The system also includes a stationary shaft, and a bearing constructed
and arranged to rotate the rotatable carrier and the blades around the
shaft. The rotatable carrier is provided with a space for at least
partially receiving a portion of the shaft.