Method of Measuring Field Emission Current Under High-Voltage Pulse

A method of measuring field emission current under high-voltage (HV) pulse is proposed. The method makes it more convenient to study electron emission under HV pulse. Based on the Kirchhoff law, this method can fundamentally solve the problem, which the emission current is usually covered up by the displacement current. In addition, the method can ensure the safety of oscilloscope and the accuracy of the measurement when the gap gets breakdown. The resolution analysis of this method is carried out. The resolution is positively correlated with the output resistance and negatively correlated with the summation of output capacitance and electrodes capacitance. The resolution, under microsecond and millisecond HV pulse, can achieve $\mu $ A to A class. The measurement platform based on this method contains an energy-storage capacitor, a load resistor, an HV pulse power supply, an electrode cavity, and three resistor-capacitor (R–C) voltage dividers.