Triggering a radial multichannel pseudospark switch using electrons emitted from material with high dielectric constant

The electron emission from a field emission trigger unit was matched to the requirements for the simultaneous ignition of all channels in a radial multichannel pseudospark switch for a large parameter range of the pseudospark discharge. In such trigger unit the electrons are extracted from the surface of a high-e material by field emission after applying a pulsed voltage. Electron emission occurs in a pressure range from 1-50 Pa, where the pseudospark discharge is operated. The access to low working gas pressures (<l0 Pa) using such trigger unit allows for achieving high hold-off voltages. The ignition of the pseudospark discharge was investigated by means of high speed photography and by a parallel observation of the electron beam of a single discharge channel, which occurs in hollow-cathode phase.