Abstract: The present invention relates to a color cathode-ray tube 10 having an evacuated envelope 11 with an electron gun 26 therein for generating at least one electron beam 28. The envelope 11 further includes a faceplate panel 12 having a luminescent screen 22 with phosphor lines on an interior surface thereof. A uniaxial tension focus mask 25, having a plurality of spaced-apart first metal strands 40, is located adjacent to an effective picture area of the screen. The spacing between the first metal strands 40 defines a plurality of slots 42 substantially parallel to the phosphor lines of the screen. Each of the first metal strands 40, across an effective picture area of the screen, has a substantially continuous first insulator layer 64 on a screen-facing side thereof. A second insulator layer 66 overlies the first insulator layer 64. A plurality of second metal strands 60 are oriented substantially perpendicular to the first metal strands 40 and are bonded thereto by the second insulator layer 66.

Abstract: The present invention relates to a method for pre-stressing the CRT tension mask 24 to induce creep. The method includes the steps of applying a suitable force to the mask material to induce stress therein, heating the mask material to an ultimate temperature, for a sufficient time, while under stress, to induce creep, and cooling the material.

Abstract: The invention relates to a method of electrophotographically manufacturing a luminescent screen assembly for a color CRT by utilizing materials whose volatilizable constituents are substantially completely baked-out in the same step in which the faceplate panel is frit sealed to the funnel of the tube envelope. This method eliminates a dedicated panel bake before frit sealing of the panel to the funnel.

Abstract: The method of electrophotographically manufacturing a screen assembly on an interior surface of a faceplate panel for a color CRT, according to the present invention, includes the steps of sequentially coating the surface of the panel with a conductive solution to form a volatilizable organic conductive layer and then overcoating the conductive layer with a photoconductive solution to form a volatilizable organic photoconductive layer. The conductive layer, comprising a quaternary ammonium polyelectrolyte and a surfactant, provides an electrode for the photoconductive layer and has improved electrical and physical properties compared to prior conductive layers.

Abstract: An optical element such as a rear projection screen for an image display device comprises at least two substantially rigid sheet members each having a first major surface and a second major surface providing a plane of incidence and a plane of emergence, respectively, through which light is transmitted sequentially. A first sheet member comprises a Fresnel lens, and a second sheet member comprises a lenticular lens array on each of the major surfaces thereof. The plane of emergence on the second major surface of the first sheet member includes the Fresnel lens formed of a radiation curable material. A method of making the Fresnel lens is described.

Abstract: An apparatus for fusing a polymer powder deposited on a surface of a faceplate panel of a cathode-ray tube comprises a housing having a faceplate support surface and enclosing a chamber. A shutter adjacent to the panel support surface separates the faceplate panel from the chamber. A reservoir for holding a solvent is within the chamber and at least one piezoelectric transducer communicates with the reservoir for atomizing the solvent to create a fog. A fan within the chamber distributes the fog onto the polymer powder. A method for fusing the polymer powder onto the faceplate panel also is described.

Abstract: In an electrophotographic process for manufacturing a luminescent screen assembly on an interior surface of a faceplate panel of a CRT, the panel is first coated with a conductive layer and then overcoated with a photoconductive layer. A substantially uniform charge is established on the photoconductive layer. Selected areas of the photoconductive layer are exposed to actinic radiation, through a shadow mask, to affect the charge on the layer. The unexposed areas of the photoconductive layer are developed with triboelectrically-charged, dry-powdered, light-absorptive screen structure material. The photoconductive layer is reexposed to further discharge those open areas free of the light absorptive material while retaining the charge on those areas having light absorptive matrix material thereon. The reexposure increases the voltage contrast between the exposed and the unexposed areas of the photoconductive layer.

Abstract: The method of electrophotographically manufacturing a luminescent screen on a substrate of a color CRT, according to the present invention, includes the steps of forming a photoreceptor by sequentially coating the substrate to form a conductive layer and an overcoating of a photoconductive layer, establishing an electrostatic charge on the photoconductive layer, and exposing selected areas of the photoconductive layer to visible light to affect the charge thereon. Then the photoconductive layer is developed by the application of suitable triboelectrically charged, dry-powdered screen structure materials. The improved process provides at least one wear-resistant, conductive contact patch on a peripheral portion of a surface of the substrate. The contact patch has a first portion which underlies at least one of the layers of the photoreceptor and is in electrical contact with the conductive layer, and a second portion which extends from the photoreceptor.

Abstract: The method of electrophotographically manufacturing a luminescent screen assembly on a substrate for use within a CRT, according to the present invention, includes the steps of: forming a conductive layer on the substrate; overcoating the conductive layer with a photoconductive solution comprising an organic polymeric material, a suitable photoconductive dye, a plasticizer and a solvent to form a photoconductive layer; and, then, establishing an electrostatic charge on the photoconductive layer. Selected areas of the photoconductive layer are exposed to visible light to affect the charge thereon, and the photoconductive layer is developed with charged screen structure material. The improved method utilizes a dialkyl phthalate plasticizer which is selected from the group consisting of dibutylphthalate (DBP), dioctylphthalate (DOP), and diundecylphthalate (DUP).

Abstract: A method of electrophotographically manufacturing a luminescent screen on an interior concave surface of a CRT faceplate panel having a major axis with a first center of curvature and a minor axis with a second center of curvature, the method including the steps of utilizing a charging apparatus for uniformly charging a photoconductive layer disposed on the concave surface of the faceplate panel by providing a corona voltage from a corona generator to at least one corona charger which has an arcuately-shaped charging electrode, the corona charger has a center of curvature substantially concentric with a center of curvature of the concave surface of the panel, a support arm attached to the corona charger is pivotably located at the other center of curvature, the corona charger substantially conforms to, and is spaced from the photoconductive layer on the concave surface, and moving the corona charger across the concave surface.

Abstract: An apparatus for uniformly charging a photoconductive layer disposed on an interior, non-planar surface of a faceplate panel of a CRT during electrophotographic screen processing of the panel includes a corona generator having at least one corona charger and a mechanism for moving the corona charger across the non-planar surface of the faceplate panel. The corona charger substantially conforms to, and is spaced from the photoconductive layer on the non-planar, interior surface of the faceplate panel.

Abstract: A method for making a dark, adherent coating on exposed metal surfaces of a color-selection electrode assembly of a CRT includes the steps of applying a first solution of aqueous phosphoric acid to the metal surfaces of the assembly; contacting the metal surfaces with a second solution of selenium dioxide and methanol; rinsing the assembly; and then, applying a sealing solution to the surfaces of the assembly.

Abstract: A color picture tube includes an inline electron gun for generating and directing three inline electron beams along coplanar beam paths toward a screen. The gun includes a plurality of electrodes which form a beam-forming region, a prefocusing lens, and a main focusing lens for the electron beams. The prefocusing lens includes four active surfaces. At least one of the active surfaces has asymmetric prefocusing recesses formed therein.