{TAIL ~ a laser} optically coupled to {HEAD ~ said first light input} via a first optical fiber and optically coupled to said second light input via a second optical fiber 
{ TAIL ~ a laser } optically coupled to { HEAD ~ said first light input } via a first optical fiber and optically coupled to said second light input via a second optical fiber
TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH 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 OTH