Study of multi-function electron gun based on CNTs cathode

A multi-function electron gun is demonstrated in this work. Through the grid type focusing electrode of the electron gun, the electron gun integrates the function of vacuum measurement. The simulation results reveal that the electron gun has ability to focus the electron beam. And its vacuum measurement range is from 10$^{-6}$ to 10$^{-3}$ Pa. The multi-function electron gun has practical application value in small scale vacuum electronic devices.