In a color picture tube of the single-gun, plural-beam type in which a central beam and two side beams originate in a common horizontal plane and are all made to pass through the center of an electron lens for focussing the beams on the color screen with the central beam emerging from the lens along the optical axis of the latter and the side beams emerging from the lens along paths that are oppositely divergent from the axis, the divergent side beams are acted upon by an electrostatic convergence deflecting device constituted by pairs of horizontally spaced plates arranged along the divergent paths and having voltages applied thereacross to produce electric fields by which the divergent side beams passing therethrough are deflected to converge at a common spot with the central beam on the apertured grill or mask associated with the screen, and a main deflection yoke produces magnetic fields by which the beams are deflected horizontally and vertically, respectively, for causing the beams to scan the screen; the horizontal distances between the plates of each pair are varied in the vertical direction from a maximum at the common horizontal plane to minimums at the opposed edges of the plates remote from such common plane so as to correspondingly vary the strengths of the electric fields and thus correct distortions in the rasters of the side beams.
This application is a division of our copending application Ser. No. 813,827, filed Apr. 7, 1969, now U.S. Pat. No. 3,619,687 and having a common assignee herewith.
This improved wall receptacle has a housing with slots in the front wall for receiving the prongs of electrical cord fittings and has terminals in the housing held in depressions of the housing and in position to contact with the prongs that are inserted through the slots. These terminals are constructed with barrels that grip conductors of a power cable and that can be secured to the cable before being inserted into the housing. In the preferred construction, the terminals are held in the housing by a back portion of the housing that is detachably connected to the portion into which the terminals fit. The construction can be made so that the power conductors require no bending for either entrance or termination. A ground connection can also be provided with the barrel clamping feature for the ground wire.
A color display system includes a cathode-ray tube and yoke. The yoke is a non-converging type. The cathode-ray tube has en electron gun assembly for generating and directing three electron beams, located at the corners of an equilateral triangle, along paths toward a screen of the tube. The electron gun assembly comprises three electron guns each including electrodes that comprise a beam-forming region and electrodes that form a main focusing lens in the path of each electron beam. The main focusing lens is formed by at least two focusing electrodes. The focusing electrode closest to the beam-forming region includes a separated part adjacent to the paths of each of the electron beams. Each separated part forms a portion of the dipole lens structure in the path of an electron beam. Means are provided for applying dynamic signals to the separated parts which are related to the deflection of the electron beams. The dipole lens structures establish electrostatic dipole fields in the path of the three electron beams that cause the beams to converge at the screen for all angles of deflection.
A cathode-ray tube with variable energy of electrons its beam formed by an electron accelerating means and an electron focusing means which are arranged in tandem along the beam axis. The electron focusing means comprises a magnetic lens with a constant magnetic-field intensity and an electrostatic lens so arranged with respect to the magnetic lens that defocusing of the electron beam by the magnetic lens, due to variations in the energy of the beam electrons, is compensated for. The electrostatic lens comprises two axisymmetric electrodes, the first electrode being electrically associated with the electron accelerating means, along the beam axis, and the second electrode being electrically associated with the screen of the cathode-ray tube.
A cathode-ray tube with variable energy of electrons of a beam formed by an electron accelerating means and an electron focusing means which are arranged in tandem along the beam axis. The electron focusing means comprises a magnetic lens with a constant magnetic-field intensity and an electrostatic lens so arranged with respect to the magnetic lens that defocusing of the electron beam by the magnetic lens, due to variations in the energy of the beam electrons, is compensated for. The electrostatic lens comprises two axisymmetric electrodes, the first electrode being electrically associated with the electron accelerating means, along the beam axis, and the second electrode being electrically associated with the screen of the cathode-ray tube.
A color display system includes a cathode-ray tube and yoke. The yoke is a non-converging type. The cathode-ray tube has an electron gun for generating and directing three electron beams, a center beam and two outer beams, along paths toward a screen of the tube. The electron gun includes electrodes that comprise a beam-forming region and electrodes that form a main focusing lens. The main focusing lens is formed by at least two focusing electrodes. The focusing electrode closest to the beam-forming region includes at least two spaced parts. Each spaced part forms a portion of a dipole lens structure in the path of an outer electron beam. Means are provided for applying to at least one of the spaced parts a dynamic signal which is related to the deflection of the electron beams.
