CATHODE STRUCTURE FOR CATHODE RAYS PIPE

摘要

PURPOSE: A cathode structure for a cathode rays pipe is provided to prevent a deterioration by forming metal and oxide in an intermediate interface of a thermal electron emission layer and a gaseous metal. CONSTITUTION: A cathode sleeve(10) is inserted into a heater(9). A base metal(11) is formed on the cathode sleeve(10), the chief ingredient of which is Ni. The base metal(11) includes a reducing agent of extremely small quantities such as magnesium and silicon. A thermal electron emission layer(10) is formed on the base metal(11). The chief ingredient of thermal electron emission layer(10) is barium carbonate(BaCo3), strontium carbonate(SrCo3) and calcium carbonate(CaCo3). An intermediate layer(13) constitutes iridium(Ir) or iridium oxide(IrO2). The intermediate layer(13) is formed at the mediate of the base metal(11) and the thermal electron emission layer(10). Iridium deposits under an atmosphere of argon(Ar) or under an atmosphere mixtures of argon(Ar) and oxygen(O2).