Cathode-ray tube for displaying coloured pictures

Claim 1

A cathode-ray tube for displaying color pictures comprising in an evacuated envelope: three electron guns the axes of which are parallel to the main axis of the tube for producing three electron beams, a color selection electrode comprising a multitude of apertures, a display screen having three patterns of regions luminescing in different colors, means for converging the three electron beams so that they intersect each other near the color selection electrode, each of said electron beams being assigned to one of the said patterns by means of the color selection electrode, each of said electron guns comprising a set of successively arranged electrodes including at least a cathode, a control grid, an anode and an additional last electrode which has the form of a substantially cylindrical sleeve, at least two electron guns having respectively, a center axis which is eccentric relative to the main axis of the tube, the last electrode of each of said two eccentric electron guns having a center axis which is eccentric relative to the center axis of the assigned electron gun in a plane through the main axis of the tube and the center axis of the assigned electron gun and at a larger disTance from the main axis of the tube than is the axis of the assigned electron gun, and said last electrode having an inner diameter which is larger than the largest inner diameter of any other electrode of the assigned electron gun.