{HEAD ~ A scraper mirror} reflects {TAIL ~ the beams} to a thermal imager which reflects the beams to a pair of NaCl beamsplitters 
reflects
{ HEAD ~ A scraper mirror } reflects { TAIL ~ the beams } to a thermal imager which reflects the beams to a pair of NaCl beamsplitters
HEAD HEAD HEAD HEAD HEAD HEAD HEAD REL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH