The method 1 wherein {HEAD ~ the first, second and third paths} define {TAIL ~ a central window portion} having a solid radiation conducting path between an upper and lower portion thereof 
The method 1 wherein { HEAD ~ the first , second and third paths } define { TAIL ~ a central window portion } having a solid radiation conducting path between an upper and lower portion thereof
OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD HEAD HEAD HEAD HEAD HEAD REL TAIL TAIL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH