Multi-needle electrodes surface discharge behavior observed by Pockels effect technique

The Pockels effect technique is improved so that it is capable of observing the dynamic behavior of the surface charge distribution. Electrons are the main carriers responsible for the surface discharge. Positive streamer channels can also be deflected in an electric field. Surface charges distort the surface field, and the resulting field in turn deflects streamer channels into much more irregular tree patterns. However complicated the trajectory of streamer channels becomes, the channels never cross each other.