Paschen, in 1889, studied the breakdown physics of gases in planar gap regions [13]. The result of Paschen showed that breakdown process is a function of the product of the gas pressure and the distance between the electrodes. Paschen showed that
Paschen's Law is an equation that gives the breakdown voltage, that is the voltage necessary to start a discharge or electric arc, between two electrodes in a gas as a function of pressure and gap length. It is named after Friedrich Paschen who discovered it empirically in 1889.