Anastigmatic deflection coil system for CRT - has two coils with deflection directions perpendicular to each other and has correction coils

摘要

The coils are so designed, that anastigmatism is present in the picture diagonals, and astigmatism in the two deflection directions. Correction coils are mounted on the core of the deflection coils, symmetrically to the deflection directions. They correct the deflection field, so that corrections in the diagonals are inoperative when the electron beam is deflected in the diagonal direction. A separate correction is provided for each deflection direction, and when toroidal coils (10) are used, at least one coil pair for one deflection direction is at the same time used as the correction coil pair.