| 摘要 |
PROBLEM TO BE SOLVED: To provide a color cathode-ray tube comprising an electron gun having a third grid electrode capable of inexpensively enlarging the scope of optimal design of the electron gun. SOLUTION: In regard to a third grid electrode 23 of this color cathode-ray tube having a plurality of negative electrodes arranged in a transverse row emitting a plurality of electron beams, at least one transverse row of plural electron beam through holes formed facing these negative electrodes, and an electron gun comprising a first grid electrode, a second grid electrode, the third grid electrode 23, and a fourth grid electrode each composed of plate electrodes, and a plurality of electrodes each having cup shaped focusing electrodes and positive electrodes, fixed in this order to an insulation supporting body in a tube axial direction at constant intervals, cylindrical protruding parts 238 of a bore Dt protruding toward the second grid electrode side are formed in correspondence to the plurality of electron beams by press molding a single plate body, electron beam through holes 233 of a bore Db are formed on zenith faces of the cylindrical protruding parts 238, and a relation between this bore Db of the electron beam through holes 233 and the bore Dt of the cylindrical protruding part 238 is Dt >= Db.
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