Abstract: An in-line type electron gun using a field superimposing type main lens system is provided that can attain good focusing properties by decreasing the size of the electron beam spot on the entire surface of the phosphor screen without being formed to be mechanically large. A field superimposing type main lens is formed by disposing two tubular electrodes opposite to each other and disposing a plate-like field correction electrode on each of the tubular electrodes on the sides not opposite to each other. On each of the opposite sides of the two tubular electrodes, an opening is formed by an edge portion and a folded portion. The shape of the opening may be an elongated flat-sided oval shaped aperture (laterally elongated aperture) that is formed by straight lines and semicircles and has a major diameter in the horizontal direction and a minor diameter in the vertical direction.

Abstract: A main lens is formed by a focus electrode, an intermediate electrode, and an anode electrode successively arranged in a traveling direction of an electron beam. The focus electrode and the anode electrode respectively have an electron beam passage aperture common to three electron beams, having a major axis in a horizontal direction in a portion opposed to the intermediate electrode, and three electron beam passage apertures through which the three electron beams pass are formed respectively in the focus electrode and the anode electrode. Aperture dimensions in a vertical direction of the electron beam passage apertures common to the three electron beams formed respectively in the focus electrode and the anode electrode are smaller than those in the vertical direction of the electron beam passage apertures formed in portions of the intermediate electrode respectively opposed to the focus electrode and the anode electrode.

Abstract: A prefocus lens section is formed by a screen electrode and an additional electrode. A main lens section is formed by a focus electrode, an anode electrode and an intermediate electrode that is disposed between the focus electrode and the anode electrode. Each of the focus electrode and the intermediate electrode has a cylindrical electrode on at least one of opposed faces thereof. The intermediate electrode and the anode electrode have cylindrical electrodes on opposed faces thereof. A voltage with a level higher than a focus voltage and lower than an anode voltage is applied to the additional electrode and the intermediate electrode.

Abstract: A prefocus lens section is formed by a second grid and a third grid in a substantially rotation-symmetric fashion. A sub-lens section is formed by the third grid and a first segment. A main lens section is formed by a fourth grid and a fifth grid. The third grid is supplied with a voltage that is higher than a focus voltage and lower than an anode voltage. An electron beam, which is prior to entering the main lens section, is shaped to have a greater horizontal dimension than a vertical dimension.

Abstract: A color cathode ray tube apparatus includes: a valve; a phosphor screen; an electron gun including an electron beam generating portion for generating three electron beams, a focusing electrode, an anode electrode, a first field correction electrode and a second field correction electrode; and a deflector for deflecting the electron beams emitted from the electron gun, wherein the focusing electrode, the first field correction electrode, the anode electrode and the second field correction electrode form an electron lens having a focusing force in a vertical direction, which is perpendicular to the horizontal direction, stronger than its focusing force in the horizontal direction inside the focusing electrode, and having a diverging force in the vertical direction greater than its diverging force in the horizontal direction inside the anode electrode, by applying a focus voltage to the focusing electrode and the first field correction electrode and applying an anode voltage higher than the focus voltage to the

Abstract: A main lens is formed by a focus electrode, an intermediate electrode, and an anode electrode successively arranged in a traveling direction of an electron beam. The focus electrode and the anode electrode respectively have an electron beam passage aperture co mmon to three electron beams, having a major axis in a horizontal direction in a portion opposed to the intermediate electrode, and three electron beam passage apertures through which the three electron beams pass are formed respectively in the focus electrode and the anode electrode. Aperture dimensions in a vertical direction of the electron beam passage apertures common to the three electron beams formed respectively in the focus electrode and the anode electrode are smaller than those in the vertical direction of the electron beam passage apertures formed in portions of the intermediate electrode respectively opposed to the focus electrode and the anode electrode.

Abstract: An in-line type electron gun using a field superimposing type main lens system is provided that can attain good focusing properties by decreasing the size of the electron beam spot on the entire surface of the phosphor screen without being formed to be mechanically large. A field superimposing type main lens is formed by disposing two tubular electrodes opposite to each other and disposing a plate-like field correction electrode on each of the tubular electrodes on the sides not opposite to each other. On each of the opposite sides of the two tubular electrodes, an opening is formed by an edge portion and a folded portion. The shape of the opening may be an elongated flat-sided oval shaped aperture (laterally elongated aperture) that is formed by straight lines and semicircles and has a major diameter in the horizontal direction and a minor diameter in the vertical direction.

Abstract: A prefocus lens section is formed by a second grid and a third grid in a substantially rotation-symmetric fashion. A sub-lens section is formed by the third grid and a first segment. A main lens section is formed by a fourth grid and a fifth grid. The third grid is supplied with a voltage that is higher than a focus voltage and lower than an anode voltage. An electron beam, which is prior to entering the main lens section, is shaped to have a greater horizontal dimension than a vertical dimension.

Abstract: At least one of the electrodes of an electron gun assembly is constructed by coupling at least first and second electrode members arranged in a direction of passing of electron beams. The first electrode member has a projecting portion on an end face thereof, which is to be coupled to the second electrode member disposed adjacent to the first electrode member. The first electrode member is coupled to the second electrode member via the projecting portion.

Abstract: A prefocus lens section is formed by a screen electrode and an additional electrode. A main lens section is formed by a focus electrode, an anode electrode and an intermediate electrode that is disposed between the focus electrode and the anode electrode. Each of the focus electrode and the intermediate electrode has a cylindrical electrode on at least one of opposed faces thereof. The intermediate electrode and the anode electrode have cylindrical electrodes on opposed faces thereof. A voltage with a level higher than a focus voltage and lower than an anode voltage is applied to the additional electrode and the intermediate electrode.

Abstract: In an electron gun for a color cathode ray tube apparatus of this invention, one intermediate electrode is arranged between a final acceleration electrode and a focus electrode that make up a main lens, and a voltage divided by a voltage dividing resistor for dividing a voltage to be applied to the final acceleration electrode is applied to the intermediate electrode. A dynamic voltage which increases along with an increase in deflection amount of an electron beam is applied to the focus electrode, and a dielectric portion is formed between the final acceleration electrode and the focus electrode. This dielectric portion is formed on the intermediate electrode. Hence, elliptical distortion of electron beam spots is decreased on the entire surface of a phosphor screen, thereby providing a color cathode ray tube apparatus with a good performance on the entire surface of the phosphor screen.

Abstract: An electron gun assembly in a cathode-ray tube apparatus includes a quadrupole lens that is created in accordance with deflection of electron beams. The quadrupole lens is created by two mutually opposing grids. The two grids have non-circular electron beam passage holes in their mutually facing surfaces. Each electron beam passage hole has a waist portion which minimizes a horizontal or vertical dimension of a region for passing the associated electron beam.

Abstract: At least one of electrodes of an electron gun assembly is constructed by coupling at least first and second electrode members arranged in a direction of passing of electron beams. The first electrode member has a projecting portion on an end face thereof, which is to be coupled to the second electrode member disposed adjacent to the first electrode member. The first electrode member is coupled to the second electrode member via the projecting portion.

Abstract: An electron gun structure applied to a color cathode-ray tube comprises a focus electrode, an ultimate acceleration electrode and at least one intermediate electrode disposed between the focus electrode and the ultimate acceleration electrode, the focus electrode, the ultimate acceleration electrode and the at least one intermediate electrode forming a main lens. The electron gun structure also comprises a voltage application unit for applying to the focus electrode a dynamic voltage increasing in accordance with an increase in a degree of deflection of the electron beams, and applying to the intermediate electrode a voltage obtained by dividing a voltage applied to the ultimate acceleration electrode by means of a voltage dividing resistor.

Abstract: A color cathode-ray tube apparatus comprises an electron gun structure having a plurality of electrodes for constituting a plurality of electron lenses including a main lens for focusing an electron beam on a phosphor screen, and a deflection yoke for producing deflection magnetic fields for deflecting the electron beam emitted from the electron gun structure in a horizontal direction and a vertical direction. An electron beam passage hole formed in at least one of the electrodes constituting the main lens has a waist portion substantially acting on formation of the electron lenses. The waist portion minimizes a horizontal dimension of a region where the electron beam passes.

Abstract: An electron gun assembly has at least one additional electrode located along the equipotential plane of a potential distribution formed between a focusing electrode and anode electrode forming a main lens. In a no-deflection state, the additional electrode receives a voltage of a predetermined level corresponding to the potential of the equipotential plane on which the additional electrode is located. In a deflection state, letting Vf be the application voltage of the focusing electrode, Eb be the application voltage of the anode electrode, and Vs be the application voltage of the addition electrode, a value (Vs−Vf)/(Eb−Vf) changes with an increase in electron beam deflection amount, while the additional electrode forms an electron lens having different focusing powers in the horizontal direction and vertical direction.

Abstract: An electron gun assembly in a cathode-ray tube apparatus includes a quadrupole lens that is created in accordance with deflection of electron beams. The quadrupole lens is created by two mutually opposing grids. The two grids have non-circular electron beam passage holes in their mutually facing surfaces. Each electron beam passage hole has a waist portion which minimizes a horizontal or vertical dimension of a region for passing the associated electron beam.

Abstract: An electron gun assembly forms an electron beam generator, pre-focusing lens, sub-lens, and main lens. The sub-lens has a weaker horizontal focusing power than the vertical one, and the main lens has a stronger horizontal focusing power than the vertical one. When the electron beam is not deflected, a first quadrupole lens is formed between the pre-focusing lens and sub-lens, and a second quadrupole lens is formed between the sub-lens and-main lens. At least one grid forming each of the first and second quadrupole lenses receives a dynamic focusing voltage which parabolically changes in synchronism with the deflection magnetic field and becomes higher when the electron beam is deflected than when it is not deflected.

Abstract: A cathode structure comprises a cathode, a cathode sleeve, a cathode holder and a cathode strap. The cathode sleeve contains a heater. A hold structure includes a cylindrical cathode support cylinder for holding the cathode structure, and a cathode support strap having an elongated plate shape and having a cylindrically curved portion engaging the cathode support cylinder. An opening portion is formed in the cylindrically curved portion of the cathode support strap. The cathode support cylinder of the hold structure and the cathode holder of the cathode structure are welded through the opening portion, and the cathode structure is held by the hold structure.

Abstract: A color cathode ray tube apparatus of this invention includes an electron gun. In the electron gun, an intermediate electrode is arranged at the mechanical center between a focus electrode and anode electrode that form a rotationally symmetric bi-potential lens. A disk-like intermediate electrode is arranged at the mechanical center between the focus electrode and intermediate electrode. The disk-like intermediate electrode has an electron beam hole with a diameter larger in the vertical direction than in the horizontal direction. The intermediate electrode has a circular electron beam hole. Voltages are applied to the disk-like intermediate electrode and intermediate electrode such that they form an electron lens similar to that formed when the disk-like intermediate electrode does not exist. Therefore, an electron beam spot is focused in an optimal manner on the entire surface of a phosphor screen, and elliptic distortion is decreased. A good image is displayed on the entire surface of the phosphor screen.