{TAIL ~ Another compensation mechanism} is {HEAD ~ a birefringent displacer} that has two sections sandwiching a half wave plate, wherein the two sections are of different widths and the planar front surface of the birefringent displacer can be positioned to be non orthogonal with respect to the incident input light beam 
{ TAIL ~ Another compensation mechanism } is { HEAD ~ a birefringent displacer } that has two sections sandwiching a half wave plate , wherein the two sections are of different widths and the planar front surface of the birefringent displacer can be positioned to be non orthogonal with respect to the incident input light beam
TAIL TAIL TAIL TAIL TAIL TAIL TAIL OTH HEAD HEAD HEAD HEAD HEAD HEAD HEAD OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH