Abstract: The present invention relates to a color CRT 10 having an evacuated envelope 11 includes a funnel 15 sealed at one end to a faceplate panel 12. A luminescent screen 22 is provided on an interior surface of the panel. A color selection electrode assembly 27 is disposed within the envelope in proximity to the screen. An internal magnetic shield 30, having an exterior surface 32, is secured to the color selection electrode assembly and is spaced from and extends along at least a portion of the funnel. A getter spring assembly 33 is disposed within the envelope to deposit a film of getter spring material onto the exterior surface 32 of the magnetic shield 30. The getter assembly 33 is improved by being detachably attached to the color selection electrode assembly 27 and prevented from rotating by an orientation plate 60 having a projection 70 with a flat contact surface that bears against the color selection electrode assembly.

Abstract: The present invention relates to a CRT 10 having an evacuated envelope comprising a funnel 11 sealed at one end to a faceplate panel 12 with a luminescent screen 14 on an interior surface thereof. A color selection electrode 16, mounted on a frame 19, is disposed within the envelope in proximity to the screen. An internal magnetic shield 22, is secured to the frame of the color selection electrode, and is spaced from and extends along at least a portion of the funnel. The magnetic shield has a plurality of openings 32 therethrough. An evaporable getter 28 is disposed within the envelope adjacent to the exterior surface 26 of the magnetic shield 22. The magnetic shield is improved by having tabs or louvers 36, 38, 136, 138, associated with the openings, for restricting the deposition of a film of getter material 30 to the exterior surface 26 of the shield 22.

Abstract: An apparatus (38) for rapidly and uniformly electrostatically charging a photoconductive layer (34) disposed on a conductive layer (32) provided on an interior concave surface of a viewing faceplate (18) of a CRT faceplate panel (12) is disclosed. The apparatus includes a housing (40) having a faceplate panel support surface (42), an electrical contact (52) for grounding the conductive layer, a corona charger (48), and power supplies (200, 204) for corona charging. The corona charger (48) includes a charging head (46) that substantially conforms to the contour of the interior concave surface of the viewing faceplate (18). The charging head comprises a base plate (54) having a mounting surface (56) to which a plurality of discrete charging modules (82) are attached. Each of the charging modules includes a focusing blade (86) and a charging blade (88, 188) insulated from the focusing blade. An ultimate focusing blade (186) is attached to the ultimate discrete charging module.

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 present invention relates to an apparatus 50 for pre-stressing a material of a CRT tension mask 24 to induce creep. The apparatus 50 includes a support frame 52 having a first major surface 54 and an oppositely disposed second major surface 56. A boss 58 is provided on the first major surface 54. A primary clamp 60 having a first jaw 62 is spaced from the boss 58 and attached to the first major surface 54. The primary clamp 60 further includes an adjustable second jaw 64 communicating with the first jaw 62 to clamp the material of the mask 24 therebetween. A movable secondary clamp 70 is located in proximity to the boss 58. The secondary clamp 70 has a third jaw 72 attached to an axle 74 that is disposed within an elongated aperture 82 formed in a support post 84 attached to the support frame 52. An adjustable fourth jaw 86 communicates with the third jaw 72 to clamp the mask material therebetween. A cam 78 having a boss engaging surface 90 is secured to the axle 74.

Abstract: A method of manufacturing a luminescent screen assembly on an interior surface of a faceplate panel 12 for a color CRT 10 includes the steps of uniformly applying a solution of a material to form an organic conductive (OC) layer and overcoating the OC layer with a solution to form an organic photoconductive (OPC) layer, on the interior surface of the faceplate panel. The OPC layer 34 is conditioned by directing a stream of dry gas thereon to warm the OPC layer to a preheat temperature, while maintaining the panel at a panel temperature less than the preheat temperature. The OPC layer is exposed to IR radiation to rapidly increase the temperature of the OPC layer to a curing temperature, greater than the preheat temperature, to remove some of the volatilizable constituents from the OPC layer, without substantially increasing the temperature of the panel.

Abstract: In accordance with the present invention, an apparatus for developing a latent image formed on a photoreceptor, which is deposited on an interior surface of an output window of a display device, is disclosed. The developing apparatus includes a developing chamber, having a support surface for supporting the output window, a screen structure material reservoir for storing, deagglomerating and feeding the screen structure material, and a triboelectric gun assembly communicating with the reservoir. The gun assembly triboelectric charges and imparts a desired charge polarity to the screen structure material. The gun assembly further includes at least one material dispersing nozzle spaced from the support surface for distributing the charged material for deposition onto the latent image.

Abstract: In accordance with the present invention, a method of electro-photographically manufacturing a luminescent screen assembly for a color CRT 10 on an interior surface of a faceplate panel 12 is described. A volatilizable, organic conductive (OC) layer 32 is provided on the interior surface of the panel and a volatilizable, organic photoconductive (OPC) layer 34 overlies the OC layer. The method includes the steps of: establishing a substantially uniform electrostatic charge on the OPC layer; exposing selected areas of the OPC layer to visible light to affect the charge thereon; developing the selected areas of the OPC layer with a triboelectrically charged dry-powdered, screen structure materials; fixing the screen structure materials to the underlying OPC layer with a suitable fixative; filming the screen structure materials; aluminizing the screen; and baking the aluminized screen.

Abstract: In accordance with the present invention, a method of electrophotographically manufacturing a luminescent screen assembly for a color CRT 10 on an interior surface of a faceplate panel 12 is described. A volatilizable organic conductive (OC) layer 32 is provided on the interior surface of the panel and a volatilizable organic photoconductive (OPC) layer 34 overlies the OC layer 32.

Abstract: In accordance with the present invention, a method of electrophotographically manufacturing a luminescent screen assembly on a photoreceptor disposed on an interior surface of a faceplate panel for a color CRT includes the steps of: charging the photoreceptor to establish a substantially uniform electrostatic voltage thereon; positioning the panel on an exposure device having a light source therein; exposing selected areas of the photoreceptor to visible light from the light source to affect the voltage thereon, without affecting the voltage on the unexposed area of the photoreceptor; and depositing a triboelectrically charged, first color-emitting phosphor onto the selected areas of the photoreceptor. The charging, positioning, exposing and depositing steps are repeated for a second and a third triboelectrically charged, color-emitting phosphor.

Abstract: In accordance with the present invention, a method of electrophotographically manufacturing a luminescent screen assembly on an interior surface of a faceplate panel 12 of a color CRT 10 comprises the steps of coating the interior surface of the panel with a volatilizable, organic conductive material to form an organic conductive (OC) layer 32, and overcoating the OC layer 32 with a volatilizable, photoconductive material to form an organic photoconductive (OPC) layer 34. Then, a substantially uniform voltage is established on the OPC layer 34, and selected areas of the OPC layer 34 are exposed to visible light to affect the voltage thereon, without affecting the voltage on the unexposed area of the OPC layer 34. Next, triboelectrically charged, light-absorbing screen structure material is deposited onto the unexposed area of the OPC layer 34 to form a substantially continuous matrix 23 of light-absorbing material having open areas therein.

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 step of forming a photoreceptor by sequentially coating the surface of the panel with a conductive solution to form a volatilizable conductive layer and then overcoating the conductive layer with an organic photoconductive solution comprising a suitable resin, an electron donor material, an electron acceptor material, a surfactant and an organic solvent to form a volatilizable photoconductive layer.

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: A cathode-ray tube comprises an evacuated envelope having a faceplate panel with a sidewall joined to a funnel. A shrinkfit implosion protection band surrounds at least a portion of the sidewall and is in contact therewith. A plurality of openings are formed in the implosion protection band to support a degaussing coil. The implosion protection band is improved over prior bands by providing a cavity in the band around at least three sides of each of the openings. The cavity is directed toward the sidewall of the panel so that the openings in the band are spaced therefrom.

Abstract: A luminescent screen assembly for a CRT is made by first coating the interior surface of a faceplate panel with a photoconductive layer which overlies a conductive layer. A multiplicity of red-, green- and blue-emitting phosphor screen elements are then deposited in color groups, in a cyclic order, onto the interior surface of the panel. A negative charge is then established on the photoconductive layer. The charge is weakened in the areas where the photoconductive layer underlies the phosphor screen elements, but unaffected in the open areas separating the phosphor screen elements. The charged, open areas of the photoconductive layer are discharged by flood illumination and reversal developed by depositing thereon particles of light-absorptive matrix material having a triboelectric charge of the same polarity as the charge established on the photoconductive layer. The novel process provides a high opacity matrix.

Abstract: A color cathode-ray tube (CRT) has a rectangular faceplate panel with a major axis and a minor axis. A viewing screen is disposed on an internal surface of the panel. The panel is sealed to a funnel along an edge of a sidewall of the panel. A color selection electrode assembly is spaced from the screen and attached to the sidewall of the panel. An internal magnetic shield has a substantially rectangular base with four corners which is secured to the color selection electrode assembly, and a flange circumscribing an aperture. A substantially continuous shield sidewall extends between the base and the flange. The shield sidewall extends backward along an inner surface of the funnel. The internal magnetic shield is improved by at least two pairs of strengthening ribs which are formed in opposite sides of the shield. The ribs are substantially parallel to the minor axis of the panel and in proximity to the flange of the shield.

Abstract: The invention relates to a manufacturing process for an impregnated cathode for an electron tube and the impregnated cathode obtained in this manner. The method consists in mixing (b) a powder (Y) containing the emissive elements (generally barium and calcium aluminates) with powder (W) of at least one refractory metal (generally tungsten, if necessary mixed with a platinum ore metal), then pressing (c) this mixture into a pellet (1) which is then sintered (d) at a high temperature in hydrogen (approx. 2000.degree. C.). In the prior art of this method, a powder of at least one refractory metal was pressed and sintered and then impregnated, machined, cleaned, etc. The process according to the invention therefore saves many steps in the manufacture of an impregnated cathode with respect to the prior art.

Abstract: A cathode-ray tube has a faceplate panel joined to a funnel. An internal magnetic shield is disposed within the tube and is connected to a bottom surface of a flange of a shadow mask frame. The flange of the shadow mask frame has a plurality of integral shield-retaining clips formed therein. Each of the clips overlaps at least a portion of the shield, to retain it in contact with the flange of the frame.

Abstract: A process for forming a color selection mask for a CRT, in a press containing a punch and a counter-punch, after a temperature build-up stage in a shaping chamber, through the circulation of pressurized hot gas injected by inlets placed on the walls of the counter-punch, includes the step of distributing the hot gas through a distribution device to uniformly heat the mask's surface.