LINEAR CATHODE AND ELECTRON GUN USING THE CATHODE

摘要

PURPOSE:To efficiently transmit the heat generated in a heating filament to a cathode. CONSTITUTION:A cylindrical insulator 20 is arranged in parallel close to a lengthy cathode body 2. The insulator 20 has an opening part 20a on the side opposed to the cathode body 2, so that the heat of a heating filament 1 provided in the insulator 20 can be transmitted to the cathode body 2 as a radiation heat. The cathode body 2 is formed of a material having a barium compound impregnated in the hole of a polar tungsten base, which can generate electrons at a comparatively low temperature.