Patent ID: 6342758
Filing Date: 2002-01-29
Classification: H01J

Abstract:
A color picture tube comprising:a panel having a fluorescent screen; a neck which accommodates an electron gun; a funnel which connects said panel and said neck; and a vacuum envelope constituted by said panel, said neck and said funnel; said electron gun having a cathode for generating three electron beams arrayed in an inline direction, a control electrode, an accelerating electrode and a main lens for focusing the electron beams on the fluorescent screen; said main lens being formed by a focus electrode to which a focus voltage is to be applied, an intermediate electrode to which an intermediate voltage between the focus voltage and an anode voltage is to be applied, and an anode electrode to which the anode voltage is to be applied; said focus electrode being cylindrical and having a fluorescent-screen side aperture which is a single aperture which surrounds the three electron beams in common, an inner plate electrode being secured to an inner wall of said focus electrodes, thickness direction of said inner plate electrode being coincident with an axial direction of said electron gun, passages of the respective three electron beams being formed by said inner plate electrode; said intermediate electrode being made of a focus-electrode side cylindrical electrode, a middle plate electrode and an anode-electrode side cylindrical electrode, said middle plate electrode having a stacked structure sandwiched between said focus-electrode side cylindrical electrode, the passages of the respective three electron beams being formed by said middle plate electrode, each of said focus-electrode side cylindrical electrode having a single aperture common to the three electron beams; said anode electrode being cylindrical and having a fluorescent-screen side aperture which is a single aperture which surrounds the three electron beams in common, an inner plate electrode being secured to an inner wall of said anode electrode, a thickness direction of said inner plate electrode being coincident with an axial direction of said electron gun, the passages of the respective three electron beams being formed by said inner plate electrode.