Display tube including a helical focusing lens with a non-rotationally symmetrical lens element.

摘要

A display tube comprising an electron gun having a beam-shaping part and a focusing structure. The focusing structure comprises an elongate hollow structure with a high-ohmic resistive layer provided on the inner and/or outer surface and comprises means for forming a non-rotationally symmetrical lens element in the area of the focusing structure. This may be a structure generating an electric multipole (for example, dipole or quadrupole) which may be incorporated particulary in the high-ohmic resistive layer.