| 摘要 |
PURPOSE: To provide a dispenser cathode which can discharge thermions stably for a long time even at a low temp. and has a longer lifetime. CONSTITUTION: A dispenser cathode includes an electron emitting substance, porous base 1a containing tungsten, a storage chamber 4a to accommodate the porous base, and a sleeve 5a to support the storage chamber firmly and accommodate a heater inside it. The feature is that the porous base contains TiO2 or ZrO2 selectively. |
