Abstract: An improved inline electron gun includes a plurality of electrodes spaced from three cathodes in the direction of a longitudinal axis of the gun. The electrodes form at least a beam forming region and a main focus lens in the paths of three electron beams, a center beam and two side beams. Each of the electrodes includes three inline apertures therein for passage of the three electron beams. The beam forming region includes the cathodes and three consecutive electrodes, a G1 electrode, a G2 electrode and a G3 electrode. The improvement comprises the G2 electrode having two linear projections on either side of the inline apertures therein. The projections parallel the inline direction of the apertures protrude in a direction parallel to the longitudinal axis, past the apertured portion of the G3 electrode in overlapping relationship therewith. On the side of the G3 electrode facing the G2 electrode, the G3 electrode has two linear channels therein on either side of the inline apertures therein.

Abstract: The present invention provides an improvement in a method of making a plurality of color picture tubes of approximately the same size and including a mix of at least two different types of electron guns therein. The electron guns include each a plurality of electrodes, with each electrode having openings for the passage of three electron beams. The improvement comprises selecting materials for each electrode of the at least two different types of electron guns that will produce a minimum difference in the focus voltage sensitivities between the two different types of electron guns.

Abstract: An electron beam deflection device for cathode ray tubes comprises a pair of vertical deflection coils, a pair of horizontal deflection coils. At least one of the vertical deflection coils and the horizontal deflection coils has a saddle shape. A rigid separator supports the deflection coil pairs and insulating one from the other. An attachment element is coupled to the separator for securing the separator to a neck portion of the tube. The attachment element has a position on the neck and extends into a region under the vertical deflection coil pair.

Abstract: An improved inline electron gun of the invention includes a plurality of electrodes spaced from three cathodes. The electrodes form at least a beam forming region and a main focus lens in the paths of three electron beams, a center beam and two side beams. The main focus lens is formed by the facing portions of two electrodes. The improvement comprises the facing portions of the main focus electrodes including a first part, and a second part positioned within the first part. The first part includes a single aperture therein. The second part includes three inline apertures therein. The first part includes four spaced ledges, and the second part is attached to the four ledges.

Abstract: A deflection yoke for a cathode-ray tube, includes a pair of vertical deflection coils, a pair of horizontal deflection coils and a rigid separator insulating the pairs of deflection coils from each other. The separator has on its surface an arrangement for positioning and holding in place front and rear parts of saddle-shaped deflection coils. The arrangement forms an integral part of a body of the separator and is produced when molding the body.

Abstract: An improved cathode structure for a cathode ray tube includes a first metal tube which can receive an emission part and a heating element, a second metal tube constituting the cathode shielding, and means for retaining the first tube in position inside the second, wherein the retaining means are constituted by a single metal piece. In a preferential mode of implementation, the metal retention piece is constituted by a crown having branches extending in the direction of the axis of the crown.

Abstract: A focusing device for a cathode ray tube comprises a plurality of substantially cylindrical permanent magnets, each having a longitudinal axis. A holder positions the magnets in an annular array at substantially equally spaced intervals in which the axes are substantially parallel to one another. Annular flanges of high magnetic permeability are disposed over longitudinally opposite ends of the magnets. First and second annular windings are symmetrically disposed substantially adjacent to and inwardly from the array of magnets. The magnetic mass of the focusing device can be varied by changing the number of magnets and/or the length of the magnets in the array. The magnets are magnetized in situ in the array by energizing a winding common to each of the magnets, after which the common winding is removed.

Abstract: An improved color picture tube includes a screen and an inline gun for generating and directing three inline electron beams along separate paths toward the screen. The electron gun includes electrodes that provide a beam-forming region, a prefocus region and a main focus region. The beam-forming region of the gun includes a cathode, a G1 electrode, a G2 electrode and a first portion of a G3 electrode. The prefocus region includes a second portion of the G3 electrode, a G4 electrode and a first portion of a G5 electrode. The main focus region includes a second portion of the G5 electrode and a G6 electrode. The improvement resides in the beam-forming region, the prefocus region and the main focus region each being astigmatic.

Abstract: A pair of E-shaped shunts are disposed near the top and bottom, respectively, of a deflection yoke for reducing inner and outer horizontal trap errors. A central portion of the E-shaped shunt reduces a ratio between magnitudes of inner and outer E-W pincushion raster distortions.

Abstract: A magnetic focusing device is disposed around the neck of a cathode ray tube. The device comprises a magnetic frame formed by constituent pieces having different magnetic permeabilities and having a gap in a portion thereof radially closest to the neck. A static focusing coil is enclosed in the frame and energized by a direct current. A dynamic focusing coil is energized by a periodically variable current and disposed between the static coil and the neck of the tube. The dynamic focusing coil is disposed near the gap and uses as a magnetic circuit the portion of the frame consisting of the material whose imaginary component of magnetic permeability is the lowest.

Abstract: A focus coil for a television is disposed between scanning electron beam generator and a planar screen and has a winding coupled between a power supply and a current sink for providing a magnetic focusing field due to current in the coil. A focusing circuit comprises a resonant circuit coupled to the focus coil for generating a parabolic current in the focus coil to account for variations in the distance between the focusing device and the screen during scanning. The resonant circuit stores a portion of the energy developed during trace intervals and returns this energy to the power supply during retrace intervals. The resonant circuit includes a capacitor and an additional coil, in series with one another, and together in parallel with the focus coil. The additional coil is magnetically coupled to the focus coil and induces a reverse current in the focus coil during the retrace interval for returning energy to the power supply.