UN TUBO DE PRESENTACION EN COLOR,PERFECCIONADO

摘要

A colour display tube comprising in an evacuated envelope an electron gun system (60) to generate three electron beams directed on a display window. For each electron beam the electron gun system (60) is provided with a cathode which is secured in a cup-shaped control grid (61) having an aperture by means of an electrically insulating material. The control grids (61) are secured in a cup-shaped anode (63) by means of a plate of electrically insulating material (62). The electron gun system (60) may be constructed with a focusing electrode (64) which is common for the three electron beams and a common accelerating electrode (67). A sleeve-shaped electrode (71) may be secured to the anode (63) in which the focusing electrode (64) is secured by means of a ring of electrically insulating material (74).