PURPOSE: To obtain a cathode heater with a high heating efficiency that is hard to be destroyed by a shock by impact heating a cathode by means of the ion produced by the cool cathode crossed field discharge performed in a rare atmosphere.
CONSTITUTION: Since the low pressure mode cool cathode crossed field discharge that is a kind of low pressure atmospheric discharge is generated and persists in the internal space of an anode 2 in which gas density is controlled at 3× 1021m-3 or less between the said anode 2 and cathode 3 and said cathode 3, is provided with the central electrode 3a that penetrates the hollow section of the said anode 2, the crossed field discharge has a property that is similar to magnetron discharge. Since the low pressure mode cool cathode field discharge has the small number of molecules density and a very few collisions occur between generated ions and molecules, the greater part of power consumed to maintain the discharge is converted into energy by which the ions impact on the cathode. Besides, the cathode heater by this invention is hard to be destroyed by the shock exerted on a filament or the like.
SUZUKI SETSUO
MORIMIYA OSAMU
