Getter arrangement in color picture tube

Claim 1

In a color picture cathode-ray tube having a plurality of electron guns comprising an envelope for evacuation, a sequential array of electrodes in each gun including an electron emitting electrode and a set of beam forming and processing electrodes and including a convergence electrode common to all said guns with structure for mounting and spacing said electrodes within said envelope, the improvement comprising, convergence electrode structure in the form of a cuplike cylindrical body having a generally closed and a generally open end with an outwardly flanged rim at its open end extending outwardly beyond the cylindrical body of the electrode, said envelope being provided with a neck portion for containing the guns being in the form of a cylindrical enclosure with a predetermined inside diameter and said convergence electrode structure having a diameter such that said rim is positioned closely adjacent the inner surface of said neck portion to thereby serve as an obstruction substantially blocking the passageway through the neck portion, beam conveyance apertures formed in the closed end of said convergence electrode body to have an inwardly extending rim portion circumferentially ridging the apertures, and a getter device mounted in the neck portion on the open end side of said convergence body and on the side opposite that at which said electron emitting electrode is located so that any particles leaving the getter when it is flashed are substantially confined by said convergence body structure to prevent their migration to the vicinity of said electron emitting electrode.