{HEAD ~ This light} is reflected from a reflective layer at the output surface and from {TAIL ~ a reflective layer} at the input surface of the member 
{ HEAD ~ This light } is reflected from a reflective layer at the output surface and from { TAIL ~ a reflective layer } at the input surface of the member
HEAD HEAD HEAD HEAD HEAD HEAD REL REL OTH OTH OTH OTH OTH OTH OTH OTH OTH REL TAIL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH