Abstract: Convergence correction device for a color display tube comprising a rolled-up flexible support provided with two convergence correction coil systems at its inner surface as well as its outer surface. The coils of each system are of the spiral-shaped type and are interconnected via metallized apertures by means of an electrically conducting strip at the opposite circumferential surface. Dependent on the specific configuration, the flexible support is wound once or twice around the neck of the display tube.

Abstract: A monochrome cathode ray tube including a magnetic focusing device provided with means for generating a static magnetic focusing field. These means surround the neck of the cathode ray tube without contacting this neck, and a system of correction coils for generating an additional focusing field and 2-, 4- and/or 6-pole fields is provided coaxially between these means and the neck of the tube.

Abstract: A cathode-ray tube (54) includes a bipotential electrode structure (50) that converges the electrons in an electron beam. The bipotential electrode structure includes a cylindrical metallic electrode (56) positioned within a neck portion (66) of an evacuated glass envelope (52) and an electrically resistive coating (58) on an interior surface (60) of the neck portion. The resistive coating has a terminal end (64) positioned adjacent the metallic electrode. An electrically and thermally conductive coating (62) on the interior surface of the neck portion covers the terminal end of the resistive coating and partly overlaps the metallic electrode. The conductive coating functions to prevent electric "punch-through" between the interior and exterior surfaces of the tubular envelope. The conductive coating also allows relatively efficient operation of a beam deflection apparatus.

Abstract: An electron beam deflection structure (10) of the traveling wave type effectively cancels the longitudinal voltage gradients and the associated electron beam defocusing that are characteristic of such deflection structures. The deflection structure comprises a first helical coil member (48) and a second helical coil member (50) that are coaxial with the longitudinal axis (26) of the tube. Each of the coil members has wide and narrow segments which alternate along the length of the coil in sequence with the turns of the coil. The first coil member has its wide segments (92a) positioned on the bottom and its narrow segment (92b) on top of the coil member. The second coil member has its wide segments (94a) positioned on top and its narrow segments (94b) positioned on the bottom of the coil member. The narrow segments from one of the coil members are interleaved with the wide segments from the other coil member.

Abstract: An imaging system for focusing and deflecting an electron beam comprises, as in prior systems, an evacuated envelope structure having a longitudinal axis and a solenoid for generating a substantially uniform magnetic field within the envelope and along the longitudinal axis thereof. As in prior systems of this type, the envelope includes an electrostatic yoke therein for generating a variable substantially uniform electric field within the envelope to deflect the electron beam along two coordinates of the system. The electric field is orthogonal to the magnetic field. An electron gun within the envelope generates and directs the electron beam through the magnetic and electric field to a target located opposite the electron gun and in a plane perpendicular to the axis of the tube. Unlike prior systems, the electrostatic yoke of the present system comprises a first conductive layer bonded to the interior surface of the envelope, and a second conductive layer overlying the first conductive layer.

Abstract: An apparatus capable of simultaneous focusing, positioning, and scanning of an ion beam is described. The apparatus uses metallic elements to form the sides of an open-ended substantially box-shaped structure. Application of AC and DC currents to the four corners of the structure create AC and DC fields within the structure that deflect an ion beam so as to perform the functions of positioning, focusing, and scanning. The center of focusing of the ion beam is placed closer to the center of scanning of the ion beam than in conventional ion beam deflection systems. As a result, the tendency of space charge beam blow-up during scanning is greatly diminished. By combining the functions of positioning, focusing, and scanning in one deflection element, the length of an ion beam deflection system is reduced, and the current capability is greatly increased.