FIG 4 illustrates optical path lengths of beam component 233 and {HEAD ~ beam component} 234 in {TAIL ~ LC based switching system} 120 
FIG 4 illustrates optical path lengths of beam component 233 and { HEAD ~ beam component } 234 in { TAIL ~ LC based switching system } 120
OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD OTH REL TAIL TAIL TAIL TAIL TAIL TAIL TAIL TAIL OTH