Deflection unit for self-converging cathode-ray tubes which includes deflection coils in the shape of a saddle

摘要

Electromagnetic deflection unit for colour cathode-ray tubes, comprising a pair of frame deflection coils and a pair of line deflection coils, at least one of these two pairs of coils having the shape of a saddle; each deflection coil in the shape of a saddle (3) having a rear end turn (19) lying flat on the electron-gun side and a front end turn (29) on the screen side, two side conductor harnesses connecting the front end turn to the rear end turn, each side conductor harness comprising a number of groups of conductors (120, 120') and having a first window (21'') in the central part of the intermediate region (24) lying between these said end turns, this window being arranged so as to minimize the trapezium differential error between the red and blue beams, and a second window (26) to the rear of the intermediate region, the resulting arrangement of the conductors making it possible to achieve convergence of the three in-line electron beams and to overcome the coma parabola error without using additional field shapers.