Color cathode ray tube having a convergence correction apparatus

摘要

A color cathode ray tube using a self-convergence method is provided with magnets for correcting top/bottom pincushion distortion, and includes a vertical deflection coil and a four-pole coil. The vertical deflection coil generates a first correction field distorted in a barrel shape. The four-pole coil is arranged on the side of a deflection yoke nearer to an electron gun, and corrects YH barrel pattern misconvergence by generating a second correction field. The strength of the second correction field varies according to the amount of vertical deflection applied to electron beams emitted by the electron gun.