Abstract: A filter for a CRT screen according to the invention is constituted such that a compound sheet consisting of a conductive net and a transparent resin film is molded so as to be closely attached to the CRT screen, and also to avoid the occurrence of moire fringes, the mesh of the net is selected at a suitable value such that the ratio of the pitch of the scanning lines of the CRT and the pitch of the wires of the net does not fall near simple integers or the inverse numbers thereof. The filter can shut off the electromagnetic waves, electrostatic charge, ultraviolet rays, etc. which are generated from the CRT, without spoiling the resolution of the CRT and can substantially prevent adverse influences on the human body by the CRT. No moire fringes are produced on the screen. A hard coating treatment and a glare-proofing treatment are further performed, so that an illumination lamps or the like in the room are not reflected from the filter surface.

Abstract: A viewing screen is described, in particular the screen of a display tube, which has excellent anti-reflective properties and a method of making this screen anti-reflective. In this method the outer surface of the screen is mechanically roughened in conformity with specific requirements and subsequently an anti-reflective coating of constant thickness is applied to the roughened surface.

Abstract: The panel face plate of a cathode ray tube is provided with an irregular film which is formed by spraying a mixed solution of silicon hydroxide, alcohol and alkyl acetate onto the panel face plate.

Abstract: A video reproducing device having a flat screen loosely placed in a mounting frame. The flat screen supports an elastic safety sheet affixed thereto for providing implosion protection if the flat screen shatters. A space is created between the frame and the flat screen for accommodating a sealing compound and a thin glass plate protects the safety sheet from external objects.

Abstract: A coating for reducing specular reflection on optical glass screens comprises a partially hydrolized metal alkoxide polymer. These alkoxides have the general formula M(OR).sub.4 where M is selected from the group consisting of silicon, titanium and zirconium where R is alkyl with 1 to 6 carbon. The equivalent titanium and/or zirconium oxides is about 15% of total solids by weight. A presently preferred coating mixture is prepared by dissolving tetraethyl orthosilicate in alcohol, at an elevated temperature; gradually adding a mixture of nitric acid and water; gradually adding titanium butoxide and/or zirconium n-propoxide; and, adding and mixing additional water and alcohol. The coating is applied by a method comprising the steps of cleaning the surface of the optical glass screen; preheating the glass screen; coating the solution onto the glass screen; and, baking the glass screen and solution, at a temperature high enough to drive off the solvent and bond the coating mixture to the glass surface.

Abstract: A cathode-ray tube with a target face consisting of electron-absorbing and nfrared emitting islands of material on a thermally-conductive substrate. A modulated electron beam scanned over a regular array of such islands induces a mid or far infrared image in the array. The tube envelope has an infrared-transparent window through which the image may be viewed by infrared detectors or imagers.

Abstract: Three-dimensional display apparatus including the combination of a cathode ray tube having a viewing face, and a line screen assembly positioned in a predetermined relationship with the viewing face. The line screen assembly includes a first line screen disposed towards the viewing face and has a number of blocking portions spaced by transparent portions. The line screen assembly also includes a second line screen positioned substantially parallel to and spaced from first line screen. The second line screen also has a number of blocking portions spaced by transparent portions. The blocking portions of the second line screen are in alignment with the transparent portions of the first line screen. Three-dimensional projection display apparatus is also disclosed.

Abstract: For cooling the faceplate of a high-energy cathode ray tube in an in-line television projection system, a cooling cell (5) constructed as a separate entity is interposed between the CRT faceplate (2) and the transmission lens (3) which is arranged in front of and in line with the cathode ray (1). The cooling cell comprises two flexible transparent diaphragms (6 and 7) which are connected at their peripheries to form an enclosure (8) for containing a cooling liquid and which are arranged in contact with the front surface 2a of the CRT faceplate and the rear surface (4) of the lens. The cooling cell has an inlet (11) and an outlet (12) through which circulating liquid enters and leaves the cell.

Abstract: A contrast enhancement structure for a full color cathode ray tube utilizes a combination of a louvered ambient light transmission control element in combination with a multi-notch band-pass filter. The louvered control elements provide limited viewing angles for incoming ambient light reducing light dispersion on the cathode ray phosphor surface. The multi-notch band-pass filter provides efficient spectral transmission in the phosphor emitting wavelengths. The combination of the louvered directional control elements for ambient light and a multi-notch band-pass filter matching the spectral emission characteristics of the color phosphor, substantially increases the contrast ratio. In fact, this arrangement provides contrast ratios which are of an order of magnitude larger than those previously possible.

Abstract: Method comprises positioning a transparent safety panel in close spaced-apart relationship with the viewing window of a CRT and producing a mechanically-strong, hydraulically-tight closure between the panel and window around the margins thereof. The cell formed thereby is filled with curable liquid resin with the window and panel in an essentially vertical orientation. After bubbles have cleared and inspection completed, the liquid resin filling the cell is cured to an optically-clear solid.

Abstract: A display device with a cooling circuit in the screen to limit the rise in temperature of the luminescent material, particularly during strong current densities of the electron beam. The device comprises a window formed of an optical fiber plate of which one or several cladding glasses have been partially removed in order to form channels for the passage of a cooling liquid while maintaining studs comprising light conductors formed by the glass core surrounded by a cladding glass of the optical fiber plate. A transparent display window having a luminescent layer is glued or sealed to the window thus constituting a cooling network connected to an external circulation by pipes embedded in moulding tubes.

Abstract: A projecton device wherein a viscous body of transparent liquid is inserted between a CRT and an enlarging projection lens, which comprises: a ring-shaped spacer for determining the positional relation between the CRT and the lens unit provided therebetween; a ring-shaped packing provided between the CRT and the lens of the lens unit at the internal side of the spacer; a thin film section having elasticity provided as part of the packing; and a space provided between the spacer and the thin film section of the packing.

Abstract: Undesired light radiations emitted by europium activated red luminescent phosphors employed in projection color televisions are greatly reduced, with essentially no reduction in the desired radiation, by employing as a filter a solution containing a soluble holmium salt and a soluble neodymium salt.

Abstract: A color image display device comprises an optical sectioning plate interposed between adjacent light emitting parts of said cathode ray tubes, and a light diffusing plate opposite to the front face of the light emitting part of said each individual cathode ray tube.

Abstract: Halos occurring around bright light spots generated by cathode ray tube devices in which the light emitted by the tubes is filtered by filtering solutions are significantly reduced by the addition of cinnamic alcohol and/or cinnamaldehyde to the solution.

Abstract: A display tube comprising in an evacuated envelope means to generate at least one electron beam which is focused on a display screen and describes a field thereon, which display screen comprises a terbium-activated blue-luminescing phosphor on a carrier, and in which the light emitted by the phosphor falls through a filter. If the energy of the emissions of the phosphor which find their origin in the .sup.5 D.sub.3 -level of terbium is at least 40% of the energy of the emissions of all terbium levels and the filter has a transmission of more than 75% at those wavelengths where the .sup.5 D.sub.3 .fwdarw..sup.7 F.sub.5 and the .sup.5 D.sub.3 .fwdarw..sup.7 F.sub.4 emissions of terbium are located and the filter has a transmission of less than 10% at those wavelengths where the .sup.5 D.sub.4 .fwdarw..sup.7 F.sub.5 and the .sup.5 D.sub.4 .fwdarw..sup.7 F.sub.4 and the .sup.5 D.sub.4 .fwdarw..sup.7 F.sub.3 emissions of terbium are located so that the color point of the filtered light is located in the range x.

Abstract: An image display device having an image transmissive faceplate with an exterior surface spaced from a light filtering layer of uniform thickness on a protective transparent panel by an encircling sealed gasket to form an interposed cavity which is filled with image transmissive bonding material. A method comprising the steps of (1) casting an annular gasket in encircling sealed relationship with an implosion panel, (2) depositing within the annular gasket and on the encircled panel a uniform thickness layer of light-filtering material, (3) sealing the gasket to an outer marginal portion of a display tube faceplate to form a cavity between the faceplate and the layer of light-filtering material on the implosion panel, and (4) filling the cavity with light transmissive bonding material.

Abstract: The invention relates to a cathode ray tube device for generating a bright blue light of the type that is particularly useful for projection color television and information display. To filter out undesired radiation emitted by a silver-activated zinc sulfide phosphor, there is located in the path of blue radiation a concentrated solution of a soluble erbium salt and Methyl Violet 2B.

Abstract: A cathode ray tube apparatus having a glass panel in front of the phosphor screen made of a material which has an X-ray absorption coefficient larger than that of the backing on which the phosphor layer is applied. The two panels are separated by means of a spacer and a liquid coolant is incorporated into the space between the panels to enhance the heat radiation effect of the phosphor surface and to avoid the radiation of X-rays.

Abstract: A cathode-ray tube comprising a glass viewing window having, on its external viewing surface, an antistatic, glare-reducing, image-transmitting coating. The coating has a rough surface and is composed essentially of a silicate material and a metallic compound in proportions to impart the desired antistatic characteristic without substantially degrading the image-transmitting capability of the coating. When the tube is operated, the coating is grounded either directly or through the metal implosion-prevention system on the tube.

Abstract: A CRT device for generating a bright green light spot is shown. The device employs a terbium activated phosphor. Troublesome radiations emitted by the phosphor particularly in the 586 nm region are significantly decreased without significant decrease of the desired 544 nm radiation by use of a concentrated solution of a soluble praseodymium salt.

Abstract: A cathode ray tube apparatus including an envelope having a panel portion with a phosphor screen formed on the inner surface thereof, a neck portion provided with an electron gun therein and a funnel portion therebetween; and a transparent panel facing the external surface of the panel portion with a peripherally located spacer therebetween, wherein a liquid coolant is sealed in the space formed between the panel portion and the transparent panel by light absorbing material, and the spacer is treated to reduce reflection.

Abstract: A filtering device for removing unwanted radiation from a green luminescing CRT comprises a solution of a soluble praseodymium salt, sodium fluorescein and Fast Green FCF.

Abstract: A frontal light extraction type beam-indexing color picture tube arrangement comprises a phosphor screen which is formed on the inner surface of the tube panel and includes an array of color phosphor stripes each of which has an appropriate afterglow time and an array of index phosphor stripes each of which has a short afterglow time and emits a light index signal representative of the scanning position of an electron beam in the forward direction of the tube panel. A photoelectric converter for receiving the light index signal is provided in front of the tube panel.

Abstract: A cathode ray tube has discrete x-ray absorbing means integrally associated with the face region thereof to beneficially attenuate the x-radiation emanating peripherally and forwardly therefrom. Attached to the tube face is a closed frame-like resilient gasket impregnated with x-ray absorbing material. Superposed thereon is a cover plate of x-ray absorbing glass. This is adhered to the tube face by a layer of substantially transparent adhesive confined within the gasket.

Abstract: A process for making an envelope for a projection televised tube, that includes a spherically curved electronic beam target surface spaced away from the neck of the tube, a larger reflective surface spherically curved concentrically with the target surface on an end plate located close to the tube neck, a target support that preferably constitutes a face plate for the envelope, and a hollow cylindrical spacer member for closing the side of the tube envelope and for holding the target support accurately spaced from the reflective surface, includes making the ends of the cylindrical member and the abutting peripheral surfaces of the end plate and target concentric with the target and reflective surfaces, so that slight relative lateral motion of the parts during assembly and bonding will not affect tube projection optics, while the relationship between the target and reflective surfaces is precisely maintained in spaced concentric relationship.

Abstract: A projection television tube includes a spherically curved electronic beam target surface spaced away from the neck of the tube, a larger reflective surface spherically curved concentrically with the target surface on an end plate located close to the tube neck, a target support that preferably constitutes a face plate for the envelope, and a hollow cylindrical spacer member for closing the side of the tube envelope and for holding the target support accurately spaced from the reflective surface. The ends of the cylindrical member and the abutting surfaces of the end plate and target support are all configured to provide joint interfaces between the elements that lie in spherical planes that are concentric with the target and reflective surfaces, so that slight lateral motion of the parts during assembly and handling will not affect tube projection optics, while the spacing between the target and reflective surfaces is precisely maintained in concentric relationship.

Abstract: An envelope for a projection television tube includes a spherically curved electronic beam target surface spaced away from the neck of the tube, a larger reflective surface spherically curved concentrically with the target surface on an end plate located close to the tube neck, a target support that preferably constitutes a face plate for the envelope, and a hollow cylindrical spacer member for closing the side of the tube envelope and for holding the target support accurately spaced from the reflective surface. The ends of the cylindrical member and the abutting surfaces of the end plate and target support are all configured to provide joint interfaces between the elements that lie in spherical planes that are concentric with the target and reflective surfaces, so that slight lateral motion of the parts during assembly and handling will not affect tube projection optics, while the spacing between the target and reflective surfaces is precisely maintained in concentric relationship.

Abstract: A holographic television system is disclosed which is capable of generating, transmitting and reconstructing three-dimensional moving pictures in real time and in color while using no more electromagnetic bandwidth for transmission than required by present-day black and white television signals.

Abstract: A luminous trace of varying length is produced upon a first non-centralized portion of the screen of a cathode ray tube used in a phototypesetter for generating characters, and is precisely imaged upon positions of a photosensitive medium. The concentration of the electron beam to generate the required trace eventually burns out the phosphor. The life of the tube is greatly extended by thereafter rotating it to position a second non-centralized portion of the screen at the optical projection axis, and so on, and thus, the cathode ray tube life is greatly extended.

Abstract: In an image converter tube, the brightness contrast of the output picture is reduced by light which is internally reflected at the surfaces of the window through which the image is viewed. The contrast can be improved by making the window partially light-absorbing, at the expense of a reduction in the overall optical gain. This gain varies considerably from tube to tube. By adding an external filter on the output window, the transmission of the filter can be chosen for each tube to provide the minimum acceptable gain and thus the maximum obtainable contrast.

Abstract: An electron discharge device including a cathode ray tube having an evacuated envelope terminated at one end in a faceplate to which a transparent panel is bonded by an interposed adhesive layer of stabilized light-transmissive material comprising a mixture of epoxy resin and a hygroscopic curing agent having a predetermined quantity of water added thereto prior to mixing with the resin.

Abstract: In a television camera tube flare is reduced without introducing vignetting by using an antihalo plate. A contact surface of the plate with the tube's window is slightly larger than a frame which is described by the tube's electron beam on a photoconductive target inside the window. An entrance face of the plate has a diagonal or diameter which is slightly larger than the contact surface.

Abstract: A cathode ray tube face plate construction for suppressing the halo on the face plate of the cathode ray tube having a face plate formed of glass with an index of refraction in the vicinity of 1.52 and with outer and inner surfaces. A fluorescent phosphor screen is carried by the inner surface. A metallic coating may overlie the phosphor screen on the side of the screen facing away from the face plate. An absorbing filter is disposed between the phosphor screen and the face plate for absorbing light emitted from the phosphor screen. An angle sensitive short wave pass filter is disposed between the phosphor screen and the absorbing filter for reflecting light emitted at a high angle from the phosphor screen.

Abstract: Cathode ray tube face plate construction for suppressing the halo on the cathode ray tube having a face plate formed of glass with an index of refraction in the vicinity of 1.52 and with outside and inside surfaces. A fluorescent phosphor screen is carried by the inside surface. An optional metallic coating overlies the phosphor screen on the side of the screen facing away from the face plate. An anti-reflection coating is carried by the outside surface of the face plate for reducing reflection from the outside surface of the face plate to suppress the central portion of the halo. A thin film interference coating is carried by the inside surface of the face plate for suppressing the outer ring-like portion of the halo. It is disposed between the phosphor screen and the inside surface of the face plate. The thin film interference coating has high transmittance for light emitted by the phosphor at near normal of incidence and high reflectance at high angle of incidence.

Abstract: Contrast enhancement filter having first and second transparent glass substrates with first and second surfaces with the first surface of each facing the medium in which the filter is disposed. A sheet-like circular polarizer is provided formed of stretched plastic members covered by layers of cellulose acetate butyrate. The circular polarizer is disposed between the first and second glass substrates and faces the second surfaces of the glass substrates. A dried plastisol primer layer is disposed on the surface of the layers of cellulose acetate butyrate facing the glass substrates. First and second layers of polyvinyl butyral adhesive secure the layers of cellulose acetate butyrate carried by the circular polarizer with the primer layers thereon to the second surfaces of the glass substrates. An anti-reflection coating is disposed on the first surface of the first substrate.

Abstract: The invention relates to light biassed camera tube arrangements of the kind in which the light bias source within the overall outline of the tube envelope has one terminal connected to a heater pin in order to provide a source of power. The other terminal of the light bias source is connected to a lead extending to a terminal carried by a protecive end base cap for the tube and a removable disc is provided to fit between the base of the tube and a valve base into which the tube is plugged, the removable disc bearing circuitry and terminals provided to contact selected ones of the terminals carried by the protective end base cap so that the nature of the light bias provided may be selected.

Abstract: A vacuum envelope contains a photoconductive target at one end and a tubular anode electrode having light scattering properties. Light is uniformly reflected onto the target by the anode electrode from a light source mounted on the other end of the tube, outside the evacuated envelope. This uniform illumination tends to reduce build-up and decay lags at low level operating conditions. The light source is removably secured to the tube on a ceramic board incorporating an electric circuit connected to the light source for adjusting and controlling the bias light intensity.

Abstract: A cathode ray display tube is provided with a contrast enhancement panel which is optically coupled to the tube faceplate. The contrast enhancement panel has a viewing surface which is spherical and concave with respect to a viewer.

Abstract: A high contrast cathode ray display tube is provided by using a color filter glass faceplate for the tube which has a narrow band of transmissivity which closely matches the display phosphor emission.

Abstract: A projection cathode ray tube has a target that is mechanically adjustable by means external to the evacuated envelope. The target extends into the evacuated space and is mounted upon a bellows that forms part of the envelope. The target is moved relative to other optical elements within the envelope by means extending through the bellows to provide both axial and pivotal adjustment after the tube is sealed. This structure enables other optical components including image reflectors to be constructed integrally with the envelope, and also improves heat transfer between the target and the external space, permitting control of the target temperature.

Abstract: An integral lens cathode ray tube system includes a cathode ray tube having an electron gun for providing a visual display on a substantially spherical-shaped viewing portion and a glass panel affixed to the viewing portion by a resin disposed therebetween and optically matched to the glass panel and viewing portion of the cathode ray tube.

Abstract: Apparatus for providing a visual display screen of the type formed from a plurality of gas cells wherein electrical voltages are capacitively coupled to selected cells to cause gas ignition and subsequent light emission, and wherein a preselected and repeatable pattern of color phosphor is deposited on selected cell surfaces in predetermined amounts to form a means for selecting any color and intensity combination over a wide range.

Abstract: A photo-conductive target pick-up tube has a vacuum sealed envelope housing a tubular anode electrode on the gun cathode side of the target. The anode electrode is roughened on its inner surface to provide light scattering from a lamp which is mounted in a cavity protruding into the envelope but which cavity is sealed from the vacuum inside the envelope. The lamp is mounted on the longitudinal axis of the axis so as to provide an artificial dark current which tends to reduce build-up and decay lag at low light level operating conditions.

Abstract: In one embodiment, a standard dot-type shadow mask color picture tube is modified by (1) increasing the glass transmission of the faceplate, and/or the mask aperture size, to increase the screen brightness; (2) making the color phosphor dots smaller and coating the space between the dots with an opaque and non-reflecting black matrix, to maintain acceptable contrast; and making the color phosphor dots sufficiently larger than the mask apertures that the beam spots on the screen are smaller than the dots (positive tolerance), to facilitate manufacture of the screen; while maintaining good purity tolerance and smaller but acceptable white uniformity tolerance. In another embodiment, a line screen-line grille shadow mask color picture tube is similarly modified.

Abstract: A cathode ray tube is disclosed which is relatively flat in the viewing direction, including a transparent envelope having at least one generally flat section, a screen arranged within the envelope, an electron gun for projecting an electron beam along a path substantially parallel to the plane of the screen, and first and second deflecting means for causing the beam to scan a line and a frame, respectively, characterized by the provision of a single conductive member of a given potential forming a beam directing electrode spaced from the screen and arranged such that the path of the electron beam lies between the electrode and the screen.