Measurement of surface charge distributions on insulating films under AC electric field in vacuum by Pockels effect

Abstract

It is thought that charging on the insulator influences vacuum surface flashover. However, the mechanism of the vacuum surface flashover and the progress from surface charging to the flashover has not been clarified sufficiently. In order to investigate the mechanism, the real-time measurement of 2-dimensional surface charge distribution has been carried out in vacuum using Pockels device. This paper describes the changes of the surface charge distributions' on an insulating film under nonuniform AC voltage application in vacuum and atmospheric condition with this technique.