Potential Distribution and Prevention of a Space‐Charge‐Induced Minimum Between a Plane Secondary Electron Emitter and Parallel Control Grid

摘要

Formulas are developed which define the profile of the electrostatic potential distribution in the semi‐infinite, space‐charge‐filled region between a plane emitter of secondary electrons and a parallel retarding‐field control grid. The calculation assumes a known secondary‐electron energy distribution and a cosine angular distribution. In practical application, the formulas must be evaluated numerically or graphically since the energy distribution cannot be expressed analytically except over limited regions. A method of determining the critical spacing between electrodes which will prevent formation of a space‐charge‐induced minimum in the potential distribution between the emitter and control grid is presented.