Color television display device including a cathode-ray tube

摘要

A color televison display device including a cathode-ray tube whose neck supports a system of deflection coils which causes isotropic astigmatic errors upon deflection. This is eliminated with the aid of a quadripolar field to which end four windings are wound preferably as four toroid windings on the core of the deflection coil system at the area of the deflection plane. The windings are arranged pairwise opposite to each other and this in such a manner that two windings are exactly located in the gaps of the field deflection coils and the two other windings are shifted 90 DEG in the tangential direction. Parabola currents which may have the line frequency and/or the field frequency must flow through the four windings. However, it is alternatively possible to replace the four windings by two each (thus a total of 8) in which a parabola current proportional to the line frequency flows through one pair of four windings and a parabola current proportional to the field frequency flows through the other pair of four windings.