A controller is used for monitoring intensity of the beam of {HEAD ~ light} emerging from {TAIL ~ the optical switch} and for providing a feedback signal to the phase shifters 
emerging from
A controller is used for monitoring intensity of the beam of { HEAD ~ light } emerging from { TAIL ~ the optical switch } and for providing a feedback signal to the phase shifters
OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD REL REL TAIL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH