JPS57199151A - Color cathode-ray tube - Google Patents

Abstract

PURPOSE:To enable the orbits of electron beams to be corrected at the central and the peripheral parts of a picture surface by regulating magnetic fields at the neck of a cathode-ray tube, while a deflection york remaining fixed, by providing electrostatic- magnetic-field generators, which are used for regulating the incidence angles of the electron beams upon the deflection york, at the neck of the tube. CONSTITUTION:The orbits of electron beams discharged from an electron gun 6 are at a certain angle relative to the axis of a cathode-ray tube 1 due to a manufacturing error. Therefore, as to the shifts of the electron beams seen from above, the traveling direction of the electron beams is adjusted to be parallel to the axis of the tube 1 by regulating the intensity and the direction of magnetic fields by use of a magnet 9a, and after that, the traveling direction of the electron beams is adjusted to correspond to the axis of the tube 1 in the same manner as above by use of the magnet 9a. Following that, as to the shifts of the electron beams seen from the side, the orbits of the electron beams are adjusted to correspond to the axis of the tube 1 in the same manner as above by means of magnets 9c and 9d. By the means mentioned above, the orbits of the electron beams are enabled to pass through the designed position of a deflection york 7 in a given direction, and the mutual distance between the electron beams at the periphery of a picture surface can be regulated.