METHOD AND APPARATUS FOR ADJUSTING STATIC CONVERGENCE AND PURITY IN COLOUR CATHODE RAY TUBES

摘要

An apparatus for adjusting the static convergence and/or the purity of a color television tube particularly of the kind having a perforated mask. A magnetizable ring encircles the neck of the tube. Poles are formed in this ring by means of coils displaceable in such manner that these coils and/or their cores are applied against the periphery of the magnetizable ring. The application of the coils or of their cores against the ring renders constant the relationship between the current supplied to these coils and the intensity of magnetization obtained.