Patent ID: 9171690
Filing Date: 2015-10-27
Classification: H01J

Abstract:
1. An apparatus comprising: a cathode; an anode, wherein the anode and cathode are receptive to a first power source to produce an anode electric potential higher than a cathode electric potential; a gate positioned between the anode and the cathode, the gate being receptive to a second power source to produce a gate electric potential selected to induce electron emission from the cathode; a suppressor positioned between the gate and the anode, the suppressor being receptive to a third power source to produce a suppressor electric potential selected to provide a force on an electron in a direction pointing towards the suppressor in a region between the suppressor and the anode; a measurement device configured to measure a separation corresponding to a pattern and configured to produce a first signal; and wherein the cathode, anode, gate, and suppressor are arranged in the pattern, and wherein the pattern is variable responsive to the first signal.