successively adding β α1 and β α2, for controlling {HEAD ~ operation} of {TAIL ~ said zoom operation processing circuit} 
of
successively adding β α1 and β α2 , for controlling { HEAD ~ operation } of { TAIL ~ said zoom operation processing circuit }
OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD REL TAIL TAIL TAIL TAIL TAIL TAIL TAIL TAIL TAIL