| 摘要 |
PURPOSE:To make it possible to obtain a stable electron emitting property under a high current intensity condition for a long time by making an electron emitting substance layer include a specific rare earth group element, and moreover, adding a specific element such as beryllium and magnesium. CONSTITUTION:A specific rare earth group element is included in an electron emitting substance layer 2a, so as to suppress the formation of an intermediate layer near the interface of the basic body. And moreover, a specific element is added to improve the conductivity of the electron emitting substance layer 2a, to secure the service life under a high current intensity operation. In this case, the specific element is at least one sort of element selected from beryllium, magnesium, titanium, vanadium, chromium, manganese, iron, cobalt, nickel, copper, zinc, boron, aluminum, gallium, indium, thallium, carbon, silicon, germanium, tin, lead, yttrium, zirconium, niobium, molybdenum, ruthenium, rhodium, palladium, silver, cadmium, hafnium, tantalum, tungsten, rhenium, and the like. |
