Electric discharge tube, for televisions and monitors, has a scandate source cathode

摘要

An electric discharge tube has a scandate source cathode with a cathode coating comprising an alkaline earth metal oxide base layer coated with alternating rhenium and scandium oxide layers. An electric discharge tube has a scandate source cathode consisting of a cathode body and a cathode coating which comprises a base layer of an alkaline earth metal- and oxygen-containing compound coated with an alternating sequence of one or more rhenium-containing layers and one or more scandium oxide-containing layers. An Independent claim is also included for a scandate source cathode as described above. Preferred Features: The rhenium-containing layer also contains tungsten, nickel or scandium oxide. The base layer contains barium oxide, aluminum oxide and scandium oxide. The cathode coating contains 40-70 at. % Re, 0.1-3 at. % Sc and 0.2-6 at. % Ba.