CATHODE-RAY TUBE

PURPOSE:To eliminate a factor of misconvergence or image distortion so as to reduce deterioration of a shape of a beam spot by disposing an orbit correcting means for an electron beam from the center of a main electron lens of an electron gun toward a panel side. CONSTITUTION:Upper projections 10a, 11a of bipolar magnets 10, 11 function as knobs for rotating the magnets 10, 11 along the circumference of a neck tube 3. When N1, S1 axes cross N2, S2 axes at the same angle with respect to the axis of a perpendicular, a magnetic field generated by the magnets 10, 11 is oriented right upward. The upper projections 10a, 11a are symmetric with respect to the axis of the perpendicular so that a change of a crossing angle of the magnets 10, 11 produces a suitable corrected magnetic field, thus correcting deviation of an electron beam. The magnets 10, 11 are disposed in such a manner that an intersection M crossing a circle orbit before correction is located at the center of the magnets, where the intersection M is positioned between the center of a fourth grid electrode G4 and a main electron lens on a panel 1 side. This position cannot influence the main electron lens.