Additionally negative phase difference can be provided to convert {HEAD ~ linear polarized light} into {TAIL ~ left handed circling polarized light} or elliptic polarized light 
into
Additionally negative phase difference can be provided to convert { HEAD ~ linear polarized light } into { TAIL ~ left handed circling polarized light } or elliptic polarized light
OTH OTH OTH OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD HEAD REL TAIL TAIL TAIL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH