Improved self converging deflection yoke for in-Line gun colour CRT.

摘要

An apparatus for applying convergence corrections to correct positional and misconvergence errors in a CRT employing a self-converging deflection yoke for magnetic deflection of an in-line colour gun assembly. Convergence correction coil windings are coupled to the deflection windings with the inductances and resistances of the convergence windings selected to match the time constants of the associated deflection windings. The applied deflection current signals are thereby apportioned between the deflection and convergence coils to modify the beam deflection and provide a beam deflecting flux proportional to the commanded deflection signals and a beam deflection centre that is independent of the pattern written on the screen. The resulting currents in the deflection coils and convergence coils are a substantial replica of the commanded deflection current signal waveforms.