TUBE IMAGE COULEUR COMPORTANT UN CANON ELECTRONIQUE EN LIGNE AVEC DES ELEMENTS DE CORRECTION COMA

The present invention provides an improvement in a color picture tube having an inline electron gun for generating and directing three inline electron beams, comprising a center beam and two outer beams, along initially coplanar paths toward a screen of the tube. The beams pass through a deflection zone adapted to have two orthogonal magnetic deflection fields established therein. A first of the fields causes deflection of the beams perpendicular to the inline direction of the beams, and a second of the fields causes deflection parallel to the inline direction of the beams. The improvement comprises the electron gun including four magnetically permeable members located near the exit of the electron gun in a fringe portion of said deflection zone. A first and a second of the members are located between the center beam path and a first and second outer beam path, respectively. A third and a fourth of said members are spaced from the first and second members, respectively, and are located on the outside of the respective outer beam paths. The first and third members and the second and fourth members have means for bypassing a part of the fringe portion of the first of the two orthogonal magnetic deflection fields, at the members, around the respective outer beam paths, while allowing another part of the same fringe portion, at the members, to pass through the respective outer beam paths. The first and second members have means for bypassing a part of the fringe portion of the first of the two orthogonal deflection fields, at the members, around the center beam path, while allowing another part of the same fringe portion, at the members, to pass through the center beam path.