Abstract:
An electron gun according to this invention includes a cathode having a hemispherical electron-emitting surface, an anode which is arranged to face the cathode, and has a first aperture on the optical axis, and a bias electrode which is arranged between the anode and the cathode, receives a potential lower than one applied to the cathode, and has a second aperture larger than the electron-emitting surface of the cathode on the optical axis. The distal end of the electron-emitting surface of the cathode is arranged in contact with or outside a sphere whose diameter is equal to the diameter of the second aperture of the bias electrode.
Abstract:
A cathode ray tube includes an electron gun directing electrons towards a faceplate having an electrode biased at screen potential. The electron beam (three beams in a color tube) is magnetically deflected to scan across the faceplate to impinge upon phosphors thereon to produce light depicting an image or information. A first pair of electromagnetic coils forward of the tube neck and deflection yoke is biased by a substantially constant current level to further deflect the electron beam. As a result, the electrons are deflected over a greater total angle than is obtained from the magnetic deflection yoke alone. A further pair of electromagnetic coils proximate the faceplate is biased by an oppositely poled substantially constant current level to direct electrons towards the faceplate, thereby to increase the landing angle of the electrons thereon.
Abstract:
An electron gun for a cathode ray tube includes a cathode assembly, a control electrode, and a screen electrode adjacent to the cathode assembly, combined, and spaced apart from each other by a gap maintainer, focusing electrodes sequentially arranged adjacent to the screen electrode, forming an auxiliary lens and a main lens, and bead glass in which portions of the cathode assembly and respective electrodes are embedded and supported.
Abstract:
The stray emission in an electron gun comprising a main lens system with one or more intermediate electrodes (42, 43, 44) between the focus electrode (41) and the anode electrode (45) is reduced if at least one of the apertures of the main lens system following the focus electrode has apertures which are smaller than those of the focus electrode. The optimal stray emission situation can be found by designing all the apertures of the main lens system. In order to manufacture an electron gun according to the invention, it is advantageous to have an outside reference system for gun mounting, because it will no longer be possible to center the electrodes on pins through the apertures.
Abstract:
A color cathode ray tube having an electron gun including a beam forming region for generating a plurality of electron beams from cathodes and directing the plurality of electron beams toward a phosphor screen along initial paths in a horizontal plane, and a main lens for focusing the plurality of electron beams on the phosphor screen. The main lens including a final lens configured so that the plurality of electron beams are focused in both horizontal direction and a vertical direction with outer electron beams among the plurality of electron beams being deflected toward a trajectory of a center electron beam among the plurality of electron beams, and a lens strength thereof being weakened with an increase in an amount of deflection of the plurality of electron beams. The color cathode ray tube further includes at least one correction lens for curvature of an image field is located between the final lens and the beam forming region, and for focusing the plurality of electron beams in both the horizontal and vertical directions and weakening focusing action on the plurality of electron beams according to the increase in an amount of deflection of the plurality of electron beams. The at least one correction lens has an electrode configuration in which trajectories of outer electron beams among the plurality of election beams are deflected one of toward and away from a trajectory of a center electron beam among the plurality of electron beams according to the increase in an amount of deflection of the plurality of electron beams.
Abstract:
A Wehnelt electrode and a cold cathode are pressed against and fixed to each other under spring force with a ceramic plate interposed therebetween. Metallized layers connected to a gate electrode and a focusing electrode are disposed on surfaces of the ceramic plate. The gate electrode and the focusing electrode are connected to external power supplies via the metallized layers as feeder path structures. With this arrangement, an electron gun for an electron tube with a cold cathode can be designed with increased degree of freedom, reduced in size, can easily be assembled at the time of manufacture, has high dimensional accuracy, provides high dielectric strength between gate and Wehnelt electrodes, and is highly resistant to vibrations.
Abstract:
An electrode of an electron gun for a cathode ray tube with an improved structure so as to enhance the flatness of the electrode. The electrode includes an electron beam passing plane on which one or more electron beam passing holes are formed, an upper sloping portion of a truncated cone shape, slantingly extending downward and outward from the peripheral edges of the electron beam passing plane, and a vertically extending portion of a cylindrical shape, extending downward from the lower portion of the upper sloping portion and extending substantially perpendicular to the electron beam passing plane.
Abstract:
A cathode system includes an impregnated pellet and a conductive cup, which has substantially cylindrical sides. The conductive cup has an open end sized to receive the impregnated pellet and a closed end. The closed end has an internal surface and an external surface. The cathode system also includes a second conductive cup. The second conductive cup also has substantially cylindrical sides, an open end and a closed end. The cathode system further includes a similar third conductive cup. The three conductive cups are electrically coupled together. For construction of the cathode, the first conductive cup receives the impregnated pellet following coupling of the three conductive cups.
Abstract:
An electron-emitting device includes a pair of electrodes and an electroconductive film arranged between the electrodes and including an electron-emitting region carrying a graphite film. The graphite film shows, in a Raman spectroscopic analysis using a laser light source with a wavelength of 514.5 nm and a spot diameter of 1 &mgr;m, peaks of scattered light, of which 1) a peak (P2) located in the vicinity of 1,580 cm−1 is greater than a peak (P1) located in the vicinity of 1,335 cm−1 or 2) the half-width of a peak (P1) located in the vicinity of 1,335 cm−1 is not greater than 150 cm−1.
Abstract:
An electron gun for cathode ray tubes (CRTs) with a helical multi-lens electrode assembly which is formed by coupling auxiliary electrodes to both ends of a helical resistive coil. The auxiliary electrodes have claws to be embedded in bead glasses, so that the helical resistive coil is mechanically supported in the electron gun. As a voltage is applied to the helical resistive coil through the auxiliary electrodes, multiple electron lenses are created due to voltage drops in each pitch of the helical resistive coil.