{HEAD ~ The anodes} of all of the extraction diodes are connected together at {TAIL ~ a common anode contact}, the common anode contact being connected to a voltage source which applies a voltage across all of the extraction diodes for operating the extraction diodes reverse biased, i.e. so as to block current flow 
{ HEAD ~ The anodes } of all of the extraction diodes are connected together at { TAIL ~ a common anode contact } , the common anode contact being connected to a voltage source which applies a voltage across all of the extraction diodes for operating the extraction diodes reverse biased , i.e. so as to block current flow
HEAD HEAD HEAD HEAD HEAD HEAD OTH OTH OTH OTH OTH OTH REL REL REL REL TAIL TAIL TAIL TAIL TAIL TAIL TAIL TAIL 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 OTH OTH OTH