| 摘要 |
PURPOSE:To increase color purity performance by additionally installing a generator of four-pole magnetic field between a deflection yoke and a CP, and decreasing the difference between central positions for horizontal-vertical deflection. CONSTITUTION:A magnet 11 which produces a four-pole magnetic field is installed between a deflection yoke 7 and a CP 9. C4B indicates a magnetic field distribution of a permanent magnet 11 which produces a four-pole magnetic field. By combination of a four-pole magnetic field distribution CP4A in a CP9 with the C4B, a SB and angle theta of an electron beam which comes into a deflection center can be selected appropriately. It means that an inclination of a straight line of H-V difference shown in the figure can be varied with two kinds of four- pole magnetic fields of the CP4A and C4B mentioned above. Therefore, by varying the location and incident angle of both side beams which come into a deflecting magnetic field, the difference between the central positions of horizontal deflection and vertical deflection can be set as small as possible and improvement of color purity can be obtained. |
