Abstract: In an electron gun assembly for a cathode ray tube, the center and side electron beams emitted from cathodes are incident on a main electric lens. The center and side electron beams are focused, respectively. The side beams are over-converged and directed to an over-converged point by the main electric lens. The side beams emerged from the main electric lens are deflected and corrected by a divergent lens so that the center and side beams are converged on a proper converged point between the screen and the over-converged point.

Abstract: A cathode-ray tube which has an electron gun and a correcting unit with a magnetic device electrically coupled to a final electrode of the electron gun so as to selectively apply a uniform magnetic field to required ones of a plurality of electron beams, so as to thereby correct the path of a selected electron beam without causing distortion in the shape of the beam spot.

Abstract: A magnetic deflector of the saddle-saddle type, for a trichromatic tube protected by a shield, with in-line guns and round-luminophor type screen, is designed to function with a saddle-torus type of magnetic deflector. The invention uses a saddle-saddle type of deflector in which the front leading-out wires have been reduced and the rear leading-out wires are laid flat. Furthermore, the ferrite piece is extended by a ring which surrounds the rear leading-out wires and is magneticlaly closed by a ferrite ring bearing a quadrupole coil powered by a parabolic current. The intention can be applied to round-luminiphor trichromatic tubes fitted with an external shield.

Abstract: A picture display device adapted for use in a projection color television receiver and comprising a monochrome display tube provided with a line deflection coil and a field deflection coil arranged contiguously in the direction of the tube axis, the line deflection coil being closer to the display screen of the picture tube. A convergence correction coil system is provided including a first convergence correction coil arranged coaxially with respect to the line deflection coil, one of such coils extending within the other, the first convergence correction coil generating a magnetic field at right angles to that produced by the line deflection coil. A second convergence correction coil is arranged coaxially with respect to the field deflection coil, one of such coils extending within the other, the second convergence correction coil generating a magnetic field at right angles to that produced by the field deflection coil.

Abstract: An electron gun for a color picture tube has beam generators for generating three electron beams and directing them toward the fluorescent screen along three paths which are parallel with each other on the same plane, and at least one pair of electrode surfaces each having three apertures centered with the three paths for forming independent main lenses so as to focus the electron beams on the fluorescent screen, the electrode surfaces being spaced apart from each other. Provided for the electrode surface are cylindrical shield members centered with the apertures and extending from the apertures in opposition to the opposing electrode surface. Outer ones of the cylindrical shield members have each an end surface inclined with respect to the center axis of the aperture so as to form inclined electric fields effective to converge the outer beams to one point to which the central beam converges.

Abstract: A color picture tube comprising three electron-gun systems, in which on the shadow mask or a part connected thereto, phosphorescent marks are attached to the rear side thereof. These marks can be used for checking the exact position of the electron beams during adjustment. By suitably delaying the chrominance signals it is possible to improve the E-W convergence.

Abstract: A multi-beam electron gun is disclosed in which a pair of outer electrodes of a convergence means (C) for converging a plurality of electron beams are divided into front and rear electrodes in the advancing direction of the electron beams and the dynamic convergence compensation of electron beams is carried out by electrodes (C.sub.3B), (C.sub.1) and (C.sub.4B), (C.sub.2), respectively.

Abstract: In a cathode ray tube apparatus having an in-line type electron gun, magnetic pole pieces comprising four pole pieces of substantially arc-shaped cross section are disposed in a cylindrical shape with circumferential gaps between neighboring pole pieces 0.degree., 90.degree., 180.degree., and 270.degree. locations on the cylinder. An additional pair of narrow width stripe-shaped pole pieces are disposed inside said cylinder at a predetermined distance from the cylinder in a manner to cover the 90.degree. and 180.degree. gaps. The apparatus acting to modify the horizontal and vertical deflection magnetic fields so that the electron beam spots on the phosphor CRT screen are substantially circular in shape without losing the self convergence effect of the magnetic fields.

Abstract: A device for displaying television pictures comprising a display tube in the neck of which an electron gun system is present for emitting at least one electron beam towards a display screen and having a deflection unit which is connected coaxially around the display tube and comprising a line deflection coil system and a frame deflection coil system both having coils of the saddle type. Each frame deflection coil comprises a number of conductors which are wound so as to produce first and second side packets, a first front end section and a second front end section which together define a first window, as well as to produce third and fourth side packets, a second rear end section and a second front end section which together define a second window which is situated within the first window.

Abstract: A cathode-ray tube including feedback means capable of producing a feedback signal indicative of the position, in at least two dimensions, of a scanning electron beam. The feedback means comprises a plurality of feedback elements disposed at selected locations within the tube enclosure. With a shadow-mask type CRT, the elements are formed on the gun-side surface of the shadow mask itself. With other kinds of CRT's, the elements are formed either on an interior supporting member or on the interior surface of the display medium. In one embodiment, the elements are formed of a phosphorescent material. In other embodiments, the elements are formed of materials capable of producing, upon excitation by a scanning electron beam, signals of visual or electrical character. The signals thus produced may be employed in a closed-loop correction system to accomplish automatic convergence and/or geometric adjustment of a displayed image.

Abstract: A device for displaying television pictures comprising a display tube in the neck of which a gun system is present for emitting at least one electron beam towards a display screen, and comprising an electromagnetic deflection unit which is provided around the envelope of the display tube and which comprises a first deflection coil and a second deflection situated coaxially with respect to the first deflection coil, each having two diametrically oppositely located coil units.

Abstract: A cathode ray tube is improved by disposing a dynamic convergence component at a location so as to minimize the electric power required for convergence correction, with respect to the positions of the deflection yoke and the static convergence component. A coma control component, if provided, is located without the axial width of the dynamic component.

Abstract: A preconverged color display station is disclosed which is compatible with a computer controlled control unit that provides electrical convergence control signals. Compatibility is obtained by causing the control unit to transmit the electrical convergence signals to the screen storage memory RAM (random access memory) which normally stores information defining the character and character attributes to be visually provided by the display station CRT screen. The stored convergence signals are read back to the control unit from the screen RAM. After all of the convergence signals have been received by the display station and prior to the transmission of character and character attribute information signals to the screen RAM, the contents of the screen RAM is erased. Subsequently, the contents of the screen RAM, which now contains character display information signals, is read out and utilized to define a visual display on a CRT.

Abstract: An in-line color-television picture tube wherein purity adjustment, vertical pincushion correction, and static convergence correction are performed by magnetic fields produced by permanent magnets acting on the beams.

Abstract: A color cathode ray tube preferably of the single gun, plural beam type wherein the beams originate on a horizontal or vertical straight line and are directed into a field produced by a horizontal-vertical electromagnetic deflection yoke at predetermined incident angles to each other so as to converge at a color screen, is provided with a magnetic yoke, for example, secured to the electron beam convergence plates at the end of the electron gun so as to be disposed in the path of the leakage flux produced by the horizontal-vertical electromagnetic deflection yoke, and thereby impart a further vertical or horizontal deflection field to at least one of the plural beams for correcting a deviation between the positions of rasters on the color screen produced by the plural beams.