Thus, in an attempt to overcome {HEAD ~ limitations} of known prior art devices, it is an object of {TAIL ~ this invention} to provide a new N×N optical switch 
Thus , in an attempt to overcome { HEAD ~ limitations } of known prior art devices , it is an object of { TAIL ~ this invention } to provide a new N×N optical switch
OTH OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH