The method 12, further comprising affixing {HEAD ~ the birefringent displacer} on {TAIL ~ a mounting frame} with respect to an optical path of the input beam after the minimum PDL is found 
on
The method 12 , further comprising affixing { HEAD ~ the birefringent displacer } on { TAIL ~ a mounting frame } with respect to an optical path of the input beam after the minimum PDL is found
OTH OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD HEAD REL TAIL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH