Deflection control structure has holes through which the beams may pass with a set of x y deflection electrodes associated with each of the holes for x y control of the trajectory of {HEAD ~ each} of {TAIL ~ the beams} 
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Deflection control structure has holes through which the beams may pass with a set of x y deflection electrodes associated with each of the holes for x y control of the trajectory of { HEAD ~ each } of { TAIL ~ the beams }
OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD REL TAIL TAIL TAIL TAIL TAIL TAIL