projecting {HEAD ~ a patterned beam} of {TAIL ~ radiation} onto a substrate held on the substrate table 
of
projecting { HEAD ~ a patterned beam } of { TAIL ~ radiation } onto a substrate held on the substrate table
OTH HEAD HEAD HEAD HEAD HEAD HEAD HEAD REL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH OTH