Abstract: An electron gun for color-picture tube device comprises a final accelerating electrode and a focusing electrode divided into plural electrode units in the axial direction of the tube. A first focusing electrode unit adjacent to the final accelerating electrode is connected to a second focusing electrode unit adjacent to the first focusing electrode unit through a resistor. A focusing voltage being change in synchronous with the deflection of an electron beam is applied to the first focusing electrode unit. The resistor is used for removing the a.c. components from the focusing voltage. Then, the removed focusing voltage is applied to the second focusing electrode. For the electron beam deflected on the peripheral part of the screen, a quadrupole lens is formed. On the first focusing electrode unit side opposite to the second focusing electrode unit are formed first electron beam path holes whose major axes extend horizontally.

Abstract: A color picture tube apparatus comprises an envelope including a funnel, a face plate and a neck, a phosphor screen on an inner surface of the face plate, an electron gun structure in the neck of the envelope for generating at least one electron beam, resistor means for supplying predetermined voltage to the electron gun structure, and deflection means for generating non-uniform deflection magnetic field to deflect the electron beam.

Abstract: A cathode ray tube apparatus comprises three cathodes arranged in line with each other in a first direction for emission of respective electron beams therefrom, a focusing electrode having first to third apertures defined therein for the passage of the respective electron beams therethrough, a quadrupole electrode structure including first to third quadrupole electrodes one for each electron beam, each of the quadrupole electrode being comprised of a pair of horizontal electrode pieces spaced a predetermined distance from each other in a second direction perpendicular to the first direction and positioned upwardly and downwardly, respectively, with respect to the associated electron beam, and a pair of vertical electrode pieces spaced a predetermined distance from each other in a direction aligned with the first direction and positioned leftwards and rightwards with respect to such associated electron beam, and a power source circuit for applying a predetermined voltage to the quadrupole electrode structure.

Abstract: An improved color display system includes a cathode-ray tube and a magnetic deflection yoke positioned on the tube. The tube includes an envelope having an inline electron gun for generating and directing three inline beams along initially coplanar paths toward a screen on an interior surface portion of the envelope. The gun includes a plurality of spaced electrodes which comprise three lenses. The first lens includes a beam-forming region for providing substantially symmetrical beams to a second lens. The second lens includes a first modulation electrode for providing asymmetrically-shaped beams to a third, or main, lens. At least one and preferably two dynamic voltage signals are applied to the modulation electrode of the second lens. Another dynamic voltage signal is applied to a second modulation electrode of the third lens. The voltage signals are related to the deflection of the beams and improve the electron beam spot size at the periphery of the tube screen.

Abstract: In an electron gun apparatus for color cathode-ray tube, first and second focusing electrodes respectively for focusing electron beams emitted from three electron guns are disposed. Between the first and second focusing electrodes, a pair of third focusing electrodes for forming an axial-nonsymmetrical electron lens are also disposed. Mutually different dynamic voltages are supplied to the third focusing electrodes in accordance with the change in deflection angle of the electron beam. Owing to the above described structure, uniform resolution is obtained at both the central part and the peripheral part of the screen.

Abstract: The present invention relates to a cathode ray tube apparatus which can reduce an astigmatism caused from the deflection distortion by providing its focusing grid in two parts and producing a dynamic focusing lens of a quadrupole between the opposing faces of the two focusing grid parts. One focusing grid preferably has vertically disposed oblong through holes, while the other focusing grid preferably has one or more horizontally disposed oblong through holes.

Abstract: A cathode ray tube comprises a series of quadrupolar lenses for focusing a beam of electrons, emitted from a cathode at one end of an evacuated envelope under the control of a control electrode, at a target screen at the other end of the envelope. After having been focused at the target by adjustment of electric potentials on the quadrupolar lenses, the electron beam will defocus upon change in a potential on the control electrode because then the crossover or initial focusing point of the electron beam will be displaced along the central axis of the envelope. With a view to ready refocusing of the beam at the target, a refocusing lens is provided between the crossover point and the quadrupolar lenses for providing a convering lens action of radial symmetry about the envelope axis. The beam can be refocused through adjustment of a single potential on the refocusing lens rather than through adjustment of several different potentials on the quadrupolar lenses.

Abstract: An improved electron deflection system for a light valve of the type used in Schlieren dark field projectors is disclosed. The deflection system eliminates one set (D box 25) of three sets of deflection electrodes used in such projectors. This is accomplished by modifying the d.c. voltages and a.c. voltages applied to the deflection electrodes. A quadrupole d.c. voltage is added to the first control box set of electrodes (61, 62) and a second quadrupole voltage of opposite sense is added to the focus deflection box set of electrodes (63, 65). This modifies the vertical and horizontal beam angles differentially and the vertical and horizontal beam trajectories differentially in a manner to compensate for the composite effects of spherical aberrations, deflection focusing aberrations, and the static starfish lens generated by the interaction of the square box electrode structure against the round drift ring assembly (21) of the deflection system.

Abstract: A color cathode ray tube system is disclosed that has a color tube with a phosphor screend. The system includes yoke means for deflecting the beams while introducing a beam-astigmatizing quadrupole field. A three-beam, in-line electron gun includes cathode means for developing the beams, and three focus lens means for receiving the electron beams and forming three focused electron beam spots at the screen of the tube. The focus lens means each has a plurality of electrode means spaced along a lens axis parallel to the other lens axes and parallel to a gun central axis, at least two of which lens axes are off-axis with respect to the gun central axis. Electrostatic quadrupole-developing means are so configured and arranged as to develop a quadrupole field in the path of each of the beams when appropriately excited, and convergence means are effective to converge the off-axis beams when appropriately excited.

Abstract: An electron gun employed in a color cathode ray tube, or the like, adapted, when electron beams are deflected in a convergence free deflecting magnetic field, to achieve optimal focused conditions for both the electron beam landing at the center and that landing at the corners of a screen by making, within a principal converging region for converging the electron beams, the converging angle in the vertical direction smaller than that in the horizontal direction and by forming, within an object point forming region, the object point in the vertical direction at a further position than where the object point in the horizontal direction is formed.

Abstract: Color display tube comprising an electron gun 5 of the in-line type. The electron gun 5 comprises a main lens which is constituted by a first focussing electrode 25 and a second focussing electrode 26. The first focussing electrode comprises sub-electrodes 27, 28 placed at a distance from each other between which an auxiliary electrode constituting an astigmatic element G.sub.AST is positioned. The auxiliary electrode G.sub.AST is connected during operation to means for applying a constant voltage, whilst at least the sub-electrode 28 forming part of the main lens is connected during operation to means for applying a control voltage. The control voltage may be a static voltage or a dynamically varying voltage, for example, a parabolic voltage which is in synchronism with the line deflection.

Abstract: A color cathode ray tube apparatus having an electron gun assembly including a device for modulating a scanning velocity of electron beams at an auxiliary lens section for clarifying an image projected to a screen is disclosed. The color cathode ray tube apparatus comprises an enclosure having a panel section, a funnel section and a neck section, an electron gun assembly, including rear electrodes disposed in front of three cathodes for emitting electron beams, each having three through-holes for passing the beams for forming an auxiliary lens for preliminarily focusing the beams, and a front electrode located in front of the rear electrodes for forming a main lens in cooperation with one electrode thereof for further focusing the beams and converging the beams.

Abstract: In an in-line electron gun for a color picture tube, 10c aligned with three cathodes 10a, 10b and 10c, through-holes of a control grid 11 and an accelerating electrode 12 are spaced by a distance S.sub.1 ; distance S.sub.2 between inlet through-holes 13a, 13b and 13c of a first focusing electrode 13 are spaced by a distance S.sub.3 ; outlet through-holes 13d, 13e and 13f of the first focusing electrode 13 and inlet through-holes 14a, 14b and 14c of a second focusing electrode 14 are spaced by a distance S.sub.3 ; outlet through-holes 14d, 14e and 14f of the second focusing electrode 14 and of an anode, 15 are spaced by a distance S.sub.4. The distances are selected to have a relation of S.sub.4 <S.sub.3 <S.sub.1 <S.sub.2, enabling misconvergence to be minimized.

Abstract: A laminar flow electron gun (16) for use in a light valve of the Schlieren dark field type is disclosed. The gun uses three accelerating electrodes (111, 112 and 113) with critical axial spacing to beam diameter ratios to allow independent adjustment and/or modulation of beam current density at the imaged aperture while reducing criticality of electrode voltages on the second and third accelerating electrodes. The design permits, but does not require, the use of a separate control grid electrode (110). The first accelerating electrode (111) is closely spaced to the cathode (119) to provide a virtual cathode at, or about, the voltage level of that electrode that reduces the thermal beam spread normally encountered in conventional electron guns. Primary control of the narrow angle beam current is by adjustment of the beam current density impinging on the final aperture (121) in the gun.

Abstract: A light valve of the Schlieren dark field type is provided with a vacuum envelope containing an electron gun, a focus and deflection assembly and a rotating disk coated with a light modulating fluid on which an electron beam from the electron gun is scanned in a raster pattern. The rotating disk has a transparent electrode which serves as as electron beam landing electrode. Between the focus and deflection assembly and the rotating disk is a drift ring assembly comprising at least two axially separated segments. The drift ring segment closest to the focus and deflection assembly is operated at a voltage to generate, in combination with the focus and deflection assembly, an electrostatic lens which corrects distortions that originate from deflection fields applied to the focus and deflection assembly.

Abstract: An electron gun for producing and directing at least one electron beam along a beam path comprises a beam forming section and a main lens section for focusing the electron beam. The main lens section includes first and second electrodes arranged along the beam path and having an aperture through which the electron beam is passed, and at least one auxiliary electrode which is located between the first and second electrodes, the auxiliary electrode having an aperture through which the electron beam is passed. The aperture of the auxiliary electrode is greater than each of the apertures of the first and second electrodes. Different voltages are applied to the first and second electrodes, and the auxiliary electrode is supplied with a middle voltage intermediate between the two voltages applied to the first and second electrodes.

Abstract: In a cathode ray tube apparatus having an in-line type electron gun, the focusing grid of the quadrupole electric field (8) which comprises the horizontal-electric-field boosting grids (11) and (11') and the vertical-electric-field boosting grids (12) and (12') is disposed between the first focusing grid (7) and the second focusing grid (9).

Abstract: An electron gun for producing and directing at least one electron beam along a beam path comprises a beam forming section and a main lens section for focusing the electron beam. The main lens section includes first and second electrodes arranged along the beam path and each having an aperture through which the electron beam is passed, and an auxiliary electrode located between the first and second electrodes and having an aperture through which the electron beam is passed. The aperture of the auxiliary electrode is wider than those of the first and second electrodes. Different voltages are applied to the first and second electrodes, and the auxiliary voltage between the voltages is applied to the auxiliary electrode. An electrostatic field formed between the first and second electrodes is corrected by placing a correcting electrode within the bathtub-shaped auxiliary electrode which is responsive to the auxiliary voltage such that the electron beams are more effectively converged.

Abstract: The spot quality of an electron beam produced by an electron gun in a cathode ray tube is improved by optimizing the dimensions of a beam-forming, apertured electrode arrangement in the gun. This arrangement includes electrodes for forming a cross-over followed by, in the direction of propagation of the electron beam, first and second lens electrodes centered around an axis, for defining an accelerating and prefocusing lens and at least two lens electrodes for defining a main focusing lens. The diameter of the aperture in the second lens electrode is smaller than twice the diameter of the aperture in the first lens electrode, and the effective spacing S-eff between the first and the second lens electrodes is smaller than 1 mm. S-eff is defined as the minimum of the function ##EQU1## where .DELTA.

Abstract: Compact deflection yoke in self-converging display system encircles adjoining segments of neck and funnel sectons of color picture tube having close beam spacing (200 mils) in electron gun to achieve low S-spacing dimension between converging beams in deflection center plane. Neck diameter is sufficiently large (1145 mils) to accommodate main focusing lens having major transverse dimension more than three and half times the beam spacing in the electron gun. Main focusing lens is formed between final focus electrodes having recessed apertures at juxtaposed ends. Walls of successive recesses have "racetrack"-like and "dogbone"-like contours. Asymmetric beam forming lenses provide each beam traversing the main focusing lens with asymmetric cross-section having relatively reduced vertical dimension.

Abstract: A generally box shaped, electronic lens system is incorporated in a cathode ray tube for amplification of both horizontal and vertical deflections of the electron beam. The lens system comprises two electrodes, one partly nested in the other with an insulating gap therebetween and both so disposed as to encompass the trajectories of the beam from the deflection system to the target of the CRT. A postaccelerating or other postdeflection electrode is provided to exert its field upon at least the target side end of the lens system. Upon application of prescribed potentials to the two lens electrodes and to the postdeflection electrode, the lens system provides a quadrupolar lens therein for deflection amplification in both directions. The lens system further coacts with the postdeflection electrode to create another electron lens adjacent its beam exit end for converging the beam in one of the orthogonal directions of beam deflection.

Abstract: Distance between the second grid (G2) and the third grid (G3) is selected very short and electron beam passing apertures of the second grid (G2) and the third grid (G3) are selected small; the cathode ray tube has small beam spot both at small current and large current operations.

Abstract: A high-performance electron gun is disclosed capable of forming an ultra-small beam spot. The gun has a series of apertured electrodes of various dimension for receiving a range of electrical potentials for forming the beam spot on a cathodoluminescent screen located a predetermined throw distance from the end of the gun. Because of its capability in forming relatively small spot sizes of the order of ten mils or less, the gun finds application in high-resolution monitors, projection television tubes and in cathode ray tubes operating on the beam index principle.

Abstract: An ultra-short high-performance LoBi electron gun is disclosed for use in very short cathode ray tubes. The gun comprises lower end means having a cathode for developing an electron beam, at least one apertured plate grid electrode for forming the beam in conjunction with the cathode, and at least one apertured plate prefocusing electrode for developing a crossover in the beam in conjunction with the grid electrode. The gun also comprises a main focus lens means for receiving, focusing and accelerating the beam. The lens means includes cylindrical focusing electrode means for focusing a beam spot of minimum size on the screen. The spacing between the focusing electrode and the prefocusing electrode, and the relative difference in potential therebetween, is effective to develop a weak electrostatic field for forming a steeply expanding beam, while cylindrical accelerating electrode means provides for accelerating the beam.

Abstract: A high-performance, unipotential-type electron gun is disclosed. The gun according to the invention comprises a series of apertured electrodes having electrical potentials thereon for establishing electrostatic fields therebetween. The electrodes, which are aligned in spaced relation on an axis, are in the order named, lower end means including a cathode for generating a source of electrons from which an electron beam is formed, apertured plate control and grid electrodes for forming, in conjunction with a cathode and the control electrode, a first cross-over constriction in the beam. The beam exhibits upon divergence from the cross-over constriction a relatively steep cross-over emergence angle. The gun includes a three-element focus lens means for producing a finely focused electron beam.

Abstract: The disclosed electron gun comprises a main focussing electron lens formed of three aligned grids and an acceleration electron lens preceding the main electron lens and formed of first two of those grids or of a first one of those grids and another grid preceding it. The acceleration lens is disposed at such a position that the principal plane for an object space of the lens is located adjacent to a virtual object point of the outermost electron ray of an electron beam incident upon the lens. Lengths of the grids forming both lens are described.

Abstract: An electron gun comprises cathodes for emitting three electron beams, and grid electrodes forming at least two asymmetric electrostatic lenses along three electron gun axes. The lenses focus and deflect the electron beams to converge on a color cathode ray tube screen. The first asymmetric lens, in response to the focus voltage being varied, deflects the beam at a first angle and the second asymmetric lens deflects the beam at a second angle to compensate for the first angle deflection caused by the first asymmetric lens.

Abstract: The electron gun, which is especially adapted for use in color picture tubes, comprises in the order named: a cathode, an apertured-plate control grid (G1), an apertured-plate screen grid (G2), and at least two tubular focusing electrodes. The quality of the gun's beam spot is improved by: 1. Establishing an operating electric field between the G2 and G3 which is between about 100 and 400 volts/mil, thereby reducing aberration effects in the beam-forming region of the gun; 2. Making the G2 thick so as to prevent the high G3 voltage from penetrating the region between the G1 and G2, thereby allowing the G1-G2 field to provide a divergent effect on the electron beam prior to beam crossover and thus give a reduced crossover angle; 3. Spacing the main focusing lens at a distance from the G2 so as to provide an optimum filling of the main focus lens with the beam to maximize the object distance of the focusing system; and 4.

Abstract: The proposed electron beam device with variable beam energy comprises a focusing system intended to ensure constant focusing of an electron beam on a screen. The focusing system includes two electrodes successively arranged across the path of the electron beam. The first of these electrodes is electrically coupled to an accelerating electrode intended for electron beam shaping; the second electrode is connected to the screen. Interposed between the accelerating electrode and the first electrode is a variable focal power lens intended to maintain constant focusing of the electron beam regardless of changes in the energy of its electrons. The proposed device features a high resolution and a simple control circuit.

Abstract: In a unipotential type electron gun including a main lens constituted by three coaxial and spaced apart electrodes for focusing an electron beams, the length of the intermediate electrode is made to be larger than 1.1D, where D represents the inner diameter of the electrodes on both sides, and the sum of the length of one electrode located on the side of a cathode electrode, the length of the intermediate electrode, the gap length therebetween, and the gap length between the intermediate electrode and the electrode on the opposite side is set to be in a range of from 4.0D to 5.4D.

Abstract: An electron gun comprising in succession in a vacuum envelope an electron source electrode or cathode, a control grid electrode, a first accelerating electrode or anode and a first and second focussing electrode. It further comprises connections for subjecting in operation each electrode to a polarizing voltage. The first focussing electrode is raised in operation to a polarizing voltage several tens of times higher than the polarizing voltage of the anode which precedes it and the second focussing electrode is raised in operation to a polarizing voltage several times higher than the polarizing voltage of the first focussing electrode which precedes it. The first focussing electrode and the anode form thus a prefocussing lens while the second focussing electrode and the first focussing electrode form a main lens.

Abstract: A cathode ray tube is provided with a rectangular box-shaped lens intermediate the tube's screen and beam deflection plates for amplifying beam deflections in both the horizontal and vertical axes. In one form, useful in either monoaccelerator or PDA tubes, the lens includes four tubular elements disposed end-to-end and spaced apart a sufficient distance to isolate them electrically. The adjacent ends of each pair of the elements are oppositely curved to provide electron lenses having vertical cylindrical mid-surfaces. The radii of the cylindrical surfaces and the voltages applied to each element are adjusted to provide a lens system that produces minimum distortion and optimum linearity in the resultant display.

Abstract: A color cathode ray tube includes an electron gun having a distributed lens system which yields smaller spot sizes on a phosphor screen at intermediate and higher cathode currents when compared with prior art electrostatic lenses having similar diameters. The lens establishes an essentially exponentially increasing potential distribution along the electron beam path.

Abstract: A laminar flow electron gun employing a narrow, elongated cathode for forming a rectangular beam and a plurality of electrodes having narrow, elongated apertures cooperating with said cathode to draw electrons from said cathode and operate on the electrons to focus the rectangular beam onto a target by providing a parallel flow region adjacent said cathode, followed by a divergent flow region, in turn, followed by a convergent flow or focusing region.

Abstract: A cylindrical electrode for use in focusing and deflecting an electron beam is provided about its central section with eight mutually separated electrode segments arranged in a diametrical fashion for deflecting the beam, and with first and second cylindrical electrode sections at opposite ends of the electrode for focusing the electron beam.

Abstract: Multistage charged-particle accelerator for operating with accelerating voltages higher than 150 kV, consists essentially of a high-voltage insulator, a source for producing charged particles, a Wehnelt cylinder, an anode and a post-accelerating tube containing stack-wise positioned post-accelerating electrodes. A high vacuum is used for insulating the parts carrying the high voltages, at least one cylindrical screen, surrounding these parts, being interposed between them and the vacuum vessel, which can itself also function as a cylindrical screen.