PURPOSE:To correct the assembly tolerance of an electron gun by simple adjustment, and to eliminate color divergence, by forming a neck magnet which is fastened to an outer surface of a neck portion of a Braun tube, in a magnetic substance magnetized to a fixed magnetizing condition. CONSTITUTION:A neck magnet 4 is mounted to an outer surface of a neck portion 11 of a Braun tube body 1, to which an electron gun is housed. The neck magnet 4 is under a magnetizing condition that corrects the convergence and purity of a Braun tube, and it is preferable that the magnet is magnetized after a magnetic substance is fastened to the outer surface of the neck portion 11. The magnetic substance is formed by applying the mixture of powdered magnetic materials and a binder on the outer surface of the neck portion and by heating the outer surface or by winding and sticking a tape-like magnet. The neck magnet 4 made up in this manner ensures simple adjustment, can modify color divergence to a high degree and can increase the stability of the performance of the Braun tube.
展开▼
