{TAIL ~ The walls} of {HEAD ~ the light trap structure} 42 have reflective and non reflective interior surfaces which are indicated at 92, 94, respectively 
{ TAIL ~ The walls } of { HEAD ~ the light trap structure } 42 have reflective and non reflective interior surfaces which are indicated at 92 , 94 , respectively
TAIL TAIL TAIL TAIL TAIL TAIL OTH HEAD HEAD HEAD HEAD HEAD HEAD HEAD HEAD OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH