{HEAD ~ The pattern} is then measured by {TAIL ~ a parallel optical processing system} 8, such as is employed in a vidicon system 
is measured by
{ HEAD ~ The pattern } is then measured by { TAIL ~ a parallel optical processing system } 8 , such as is employed in a vidicon system
HEAD HEAD HEAD HEAD HEAD HEAD REL OTH REL REL TAIL TAIL TAIL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH