Abstract: This invention relates to an electron gun for cathode tube having red, green and blue cathode structure body composed of a combination with a sleeve having open and close type and other length, thickness, shape and the quality of material and connecting heater therein, a base metal having other shape, thickness and attached on upper edge of the sleeve and a hot electron emitting material deposited on the base metal.

Abstract: An electron tube includes a cathode structure which has a hollow cylindrical sleeve having a heater mounted within the sleeve. There is a cathode cap disposed at the top of the sleeve to contain an electron emission material. A hollow cylindrical cathode holder is used for supporting the sleeve. A unitary support interconnects the sleeve and the holder and has formed in its outer peripheral wall a plurality of circumferentially spaced through holes for preventing deformation of the support.

Abstract: A cathode structure for a cathode-ray tube includes a cathode cap coated with an electron-emissive substance for emitting electrons when heated, a cylindrical cathode sleeve attached to the bottom of the cathode cap, a heater inserted in the cathode sleeve for heating the cathode cap, a cathode sleeve holder for holding the cathode sleeve , cylindrical member for fixing the lower end of the cathode sleeve preventing electric field concentration, and a plurality of connecting arms extending from the means for connecting with the cathode sleeve holder.

Abstract: A cathode structure for supporting a cathode sleeve of a cathode ray tube includes a plurality of metal ribbons for supporting the cathode sleeve, where one end of a ribbon is fixed to an upper end of the cathode sleeve and the other end of the same ribbon is fixed to an upper end of a cathode holder, that allows thermal expansion of the cathode sleeve to occur towards the cathode holder, and maintain a constant distance between a cathode cup on the cathode sleeve and a first electrode of an electron gun.