The anodes of all of the extraction diodes are connected together at {TAIL ~ a common anode contact}, and a voltage is applied across {HEAD ~ the extraction diodes} by connecting a voltage source to the common anode contact so that the extraction diodes are reversed biased and thus block current flow 
The anodes of all of the extraction diodes are connected together at { TAIL ~ a common anode contact } , and a voltage is applied across { HEAD ~ the extraction diodes } by connecting a voltage source to the common anode contact so that the extraction diodes are reversed biased and thus block current flow
OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH TAIL TAIL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD HEAD OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH