Abstract: A monochrome cathode ray tube incorporates an electron gun featuring a focusing electrode having an upper cup-shaped portion comprising a top cylindrical sidewall portion and a lower inwardly tapering sidewall portion connecting to a flat bottom portion, the cup-shaped portion supported by an elongated cylindrical base portion having a diameter of from about 44 to 48 percent of the diameter of the upper cylindrical portion of the cup. The electron gun is particularly suitable for use in monochrome cathode ray tubes for projection color television.

Abstract: The effective aperture sizes of the final focusing and accelerating electrodes of an in-line electron gun structure for color cathode ray tubes are increased by elongating the apertures, expanding the outer edges of the side apertures, and surrounding the apertures with a peripheral raised rim which balances the asymmetry introduced into the apertures by enlargement. Partitions between the aperture may be radiused so their center height is lower than the height at the edges. The raised rim of the final accelerating electrode is generally higher than the raised rim of the focusing electrode.

Abstract: In a color cathode ray tube having an in-line electron gun with overlapping CFF lenses, the small openings of the focusing electrode apertures are critically enlarged to balance the asymmetry of the lensing field caused by the overlap, and beam spot distortion due to field asymmetries in the focus region is eliminated. Enlargement is achieved by elongating the openings in a direction normal to the in-line plane, and widening the outer openings.

Abstract: A CRT electron gun electrode is provided with an improved beam shaping region having an elongated recess coined in the upper electrode surface and an opposed coined depression in the lower surface. The double coining fabrication method assures a sharp perimetrical edge about at least the central portion of the recess, such being an important influence in achieving improved beam shaping lensing.

Abstract: In a color cathode ray tube having an in-line electron gun with overlapping CFF lenses, the accelerating electrode apertures are critically enlarged to deepen the saddles between adjacent apertures in order to balance the asymmetry of the lensing field caused by the forcusing electrode, and eliminate beam spot distortion at the screen due to field asymmetries in the focus region.

Abstract: A CRT electron gun electrode is provided with an improved beam shaping region having an elongated recess coined in the upper electrode surface and an opposed coined depression in the lower surface. The double coining fabrication method assures a sharp perimetrical edge about at least the central portion of the recess, such being an important influence in achieving improved beam shaping lensing.

Abstract: The invention pertains to the achievement of improved lensing means employed in compact plural beam in-line CRT electron gun assemblies resulting in small round spot sizes on the screen. Such is effected by forming cooperating tapered apertures in a low potential lensing electrode and similar facing apertures in an adjacent high potential lensing electrode. The larger openings of the two sets of facing tapered apertures provide lenses of larger than normal dimensions. Additionally, partial overlapping of the apertures permits even larger lenses in the available electrode areas, thereby effecting further improved lensing of the beams.

Abstract: In-line electron gun structure for color cathode ray tubes in which the final focusing and accelerating electrodes each employ three in-line tapered, partially overlapping apertures in facing relationship, and at least one aperture opening, preferably the central aperture of the focusing electrode, is elongated to provide electron beam spot-shaping.

Abstract: In-line electron gun structure for color cathode ray tubes in which the final focussing and accelerating electrodes each employ three in-line tapered, partially overlapping apertures in facing relationship, and at least one pair of electron beam spot-shaping inserts associated with the central aperture of the focussing electrode.

Abstract: The invention relates to disc-like metallic means for supporting the cathode assembly in a miniaturized cathode ray tube single electron gun structure. Its substantially planar construction with radially extending supporting leg elements incorporates shapings which achieve both compactness and ruggedness. The beneficial strengthening effects are provided by the integration of a rim on the disc portion with U-shaped cross-sectional shapings of the leg elements.

Abstract: An improved beam focusing structure, in the form of overlapping lenses, is incorporated into the forward portion of the unitized main focusing electrode of a compactly-dimensioned CRT three-beam in-line electron gun assembly. Such is accomplished by forming a common, elongated and configurated focusing electrode aperture to accommodate passage of the three beams therethrough. A pair of planar wall elements, spatially positioned in the aperture, to define the three lenses, have concave arcuately shaped forward edges formed in acccordance with the spacing between the focusing electrode and an adjacent plural apertured accelerating electrode.

Abstract: A structural beam focusing improvement is introduced into the main focusing electrode of at least one of the gun structures in a CRT plural beam bi-potential in-line electron gun assembly. This improvement, being in the form of a pair of sideboard elements, one of which is positioned on either side of a forward aperture in the unitized main focusing electrode, imparts correctional influences to asymmetries in the respective lensing field, thereby resulting in the achievement of a desired circular beam spot landing at the center of the screen.

Abstract: Means for achieving improved focusing of shaped electron beams are introduced into the low focusing electrode member of the multi-electrode distributed focusing lens of at least one of the gun structures in a CRT plural beam tri-potential in-line electron gun assembly. This improvement is in the form of a pair of substantially planar insert elements, one of which is horizontally positioned on either side of a forward aperture of the unitized low focusing electrode. These impart correctional influences to asymmetrics in the respective lensing field, and aid in alleviating subsequent spherical aberration of the shaped beam, thereby achieving a desired circular beam spot landing at the center of the screen.

Abstract: A one-piece astigmatic lens is formed in a grid by lancing a section thereof, coining the lanced section to a dimension wider than the trough formed by the lanced section and providing a beam aperture in the lanced and coined section.

Abstract: A one-piece astigmatic lens is formed in a grid by lancing a section threeof, coining the lanced section to a dimension wider than the trough formed by the lanced section and providing a beam aperture in the lanced and coined section.

Abstract: Improvement is provided in a color cathode ray tube of the post-deflection acceleration type, in the form of an operational system including related tube geometry. An electron barrier, consisting of a metallic film having a defined voltage penetration threshold, is adheringly disposed on the surface of the screen. The potential on the screen is in the order of substantially 20 to 40 kilovolts while the potential of the related color-selection electrode is more than substantially 72 percent and less than 85 percent of the screen potential thereby effecting a definitive voltage differential (.DELTA.V) therebetween that is substantially equal to or less than the voltage penetration threshold of the metallic film. The improvement in the system provides enhanced contrast and color purity in the screen display and minimizes background luminescence of the screen resultant from spurious impingement of secondary electrons generated in the tube.

Abstract: An improvement is provided in a cathode ray tube plural beam in-line electron gun assembly having applied beam currents of differing levels. At least one of the gun structures in the assembly incorporates discrete electrode modifications or differentiations whereby the respective focusing lens is dimensionally changed to effect a focused beam landing at the screen that is of a size similar to those of the beams emanating from the related guns in the assembly.

Abstract: An improvement is provided in a cathode ray tube plural-beam in-line electron gun assembly having applied beam currents of differing levels. At least one of the gun constructions in the assembly incorporates discrete electrode structural modifications whereby the respective focusing lens is dimensionally changed to effect a focused beam landing at the screen that is of a size similar to those of the beams emanating from the related guns in the assembly.

Abstract: An internal improvement is provided in a cathode ray tube wherein the electron gun assembly is positioned in close proximity to the sidewall of the encompassing neck portion of the tube envelope. The improvement is in the form of discrete shielding means incorporated in conjunction with one or more electrodes in the forward portion of a multi-beam electron gun assembly to minimize the effect of positive neck charge on the trajectories of the electron beams traversing the portions of the assembly closely related to the neck wall. Each shielding means is comprised of an element formed of substantially round wire material configurated as a U-shaped member, whereof the bottom bridge-portion of the member is substantially contiguous with the rolled rim of the associated electrode, extending outward therefrom toward but not touching the adjacent glass wall of the neck.