Television display system employing permeable correctors for a deflection yoke

A color television display system comprising:

• a kinescope incorporating a display screen and a neck and having an electron gun assembly within said neck for producing three horizontal in-line electron beams;
• a deflection yoke mounted on said kinescope neck and comprising a magnetically permeable core and horizontal and vertical deflection coils disposed adjacent said core, each of said coils producing a main deflection field and an external field, said yoke providing deflection of said electron beams for producing rasters on said display screen;
• first and second field forming means disposed at the rear of the yoke on opposite sides of the vertical axis through said kinescope neck, said first and second field forming means each comprising an upper magnetically permeable member disposed above the horizontal axis through said kinescope neck and a lower magnetically permeable member disposed below the horizontal axis through said kinescope neck, each of said members consisting of an elongated first portion disposed substantially perpendicular to the longitudinal axis of said kinescope neck and extending from the vicinity of said neck horizontally outwardly therefrom and a second portion, coupled to said first portion and disposed substantially parallel to the longitudinal axis of said neck, the vertical dimension of each of said portions being a small fraction of the diameter of said kinescope neck, said members disposed within said external fields of said horizontal and vertical coils, said first portions channelling the flux from said vertical coil external field to said second portions to form respective correcting magnetic fields between the upper members of said first and second field forming means and between the lower members of said first and second field forming means.