An LC based optical device compensates for differences in optical path lengths of {HEAD ~ polarization components} of {TAIL ~ input beam} 
of
An LC based optical device compensates for differences in optical path lengths of { HEAD ~ polarization components } of { TAIL ~ input beam }
OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD REL TAIL TAIL TAIL TAIL TAIL TAIL