{HEAD ~ an input reflective layer} located on {TAIL ~ the input surface} to substantially totally reflect light toward the output surface 
located on
{ HEAD ~ an input reflective layer } located on { TAIL ~ the input surface } to substantially totally reflect light toward the output surface
HEAD HEAD HEAD HEAD HEAD HEAD HEAD HEAD REL REL TAIL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH OTH OTH