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AssigneeSony Corporation
InventorsShoichi Muramoto, Yoshihiro Tsukamura, Masayuki Tozawa, Fusao Ishii
Estimating the term…
An electron gun used in a cathode ray tube, for example, color television picture tube, is disclosed. The electron gun has a plurality of electrodes aligned in one direction along an axis of a neck portion of the cathode ray tube. Each of the electrodes is supplied with a suitable potential for focusing and accelerating an electron beam derived by a cathode. A resistance element which comprises a ceramic substrate coated with a layer of resistive material is provided along and adjacent to the electrodes in the cathode ray tube. One end of the resistance element is electrically connected to the anode potential, and another end is connected to a stem lead pin which is at a substantially low enough potential to avoid mutual electric discharge between stem lead pins. Suitable potential for the selective electrodes is derived from intermediate taps of the resistor and electrode material are composed of a mixture of RuO.sub.2 and glass frit. The resistor is overcoated with a glass layer on the surface of the layer of resistive material and the coefficient of thermal expansion of the substrate and glass layer chosen to be similar.
An electron gun which is used for television picture tube having an evacuated bulb including a funnel portion, a neck portion and screen portion including a plurality of electrodes for focusing and accelerating an electron beam generated by a cathode, aligned along the axis of said neck portion, comprising a resistor formed of an insulating substrate on which a resistive path is formed, said substrate being mounted along said plurality of electrodes and sealed in said neck portion, said resistive path having one end tap, another end tap and at least one intermediate tap between said end taps, said one end tap being supplied with the same voltage as the voltage supplied to said screen portion, said another end tap being connected to a terminal pin provided at one end tap of said neck portion for connection to a voltage low enough to avoid an electric discharge between electrodes and said terminal pin, an operating voltage for the electrodes being obtained from said intermediate tap by dividing the voltage between both of said end taps, said resistive path comprising a mixture of ruthenium oxide and glass, and said substrate and said resistive path being overcoated with at least one layer of glass, said layer of glass contained alumina powder.
Dependencies are inferred from the claim text.