| 摘要 |
<p>PURPOSE:To provide a cathode structure of a small electrostatic input capacity and suitable for a high speed scanning by bending a sheet metal for a multiple number of times into a specified shape and securing one end thereof to a multiple number of cylindrical metallic column projected on the side of and secured to a cathode base of an insulation base disposed in the direction perpendicular to the axis of a cathode sleeve. CONSTITUTION:Three tabs 4 of a cathode comprising a cathode base 2 made of nickel, an electron emitting substance 3 formed on the base 2, a cathode sleeve 1 made of nichrome an with its inner and outer surfaces treated by oxidation are secured by welding to three wires 10 embedded in crystallized glass 9 melt-coated on an outer frame metal 8. Therefore, components for constituting a cathode potential are only the cathode sleeve 1, the cap shaped cathode base 2, tabs 4, and wires 10 so that an electrostatic input capacity constituted between a first grid, outer frame metal, and a heater may be made considerably small. This provides a cathode structure of a small electrostatic input capacity and capable of being driven at a high scanning speed.</p> |
