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