{HEAD ~ This laser beam d} causes the optical resonance action to greatly change the emission level of {TAIL ~ the laser beam source} 1 
{ HEAD ~ This laser beam d } causes the optical resonance action to greatly change the emission level of { TAIL ~ the laser beam source } 1
HEAD HEAD HEAD HEAD HEAD HEAD HEAD HEAD OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH TAIL TAIL TAIL TAIL TAIL TAIL TAIL TAIL OTH