| 摘要 |
PURPOSE:To eliminate the difference between deflection sensitivities for both side beams and center beam, in a color picture tube having an in-line electron gun, by providing a magnetic field control element in the vicinity of an electron beam emission hole of the electron gun further providing protruding parts mutually interposed with side beam emission holes. CONSTITUTION:Magnetic flux of a horizontal deflection magnetic field, absorbed to parts 27, 28, 29 and 30 of magnetic field control elements, is focused in the vicinity of parts 31, 32, 33 and 34 of the magnetic field control elements, and intensity of the horizontal deflection magnetic field in the vicinity of side beam emission holes 12 and 14 is considerably increased as compared with horizontal deflection magnetic field intensity of a side beam of a conventional deflection magnetic field control element. Accordingly, the magnetic field control elements 23, 24 function to further increase horizontal deflection sensitivities of both side beams 3 and 5 for the conventional magnetic field control element, and coma aberration can be corrected. In this way, the necessity for a convergence correction circuit can be eliminated to decrease a correction amount of pincushion distortion. |
