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