| 摘要 |
PURPOSE:To achieve correction with simple composition for misconvergence and negative distortion in a vertical line raster which is generated by a deflecting yoke which generates an approximately uniform magnetic field by making auxiliary coils generating tetrapole magnetic field components be connected in parallel with a diode and in series with a horizontal deflection coil. CONSTITUTION:Auxiliary coils 6 generating tetrapole magnetic field components are connected in parallel with a diode 8 and in series with a horizontal deflection coil 2, and further the horizontal deflection coil 2 is disposed asymmetrically to a vertical axis of a deflecting yoke 1. Thus, a current formed by nearly superposing a triangular wave and a toothed wave is made to flow at a period of horizontal deflection across the auxiliary coils 6. Upon scanning right and left edge parts of a screen, the tetrapole magnetic field components are formed with maximum forces and in the similar directions so that misconvergence and negative distortion in a vertical line raster can be corrected. Further, an ampere turn component, which is generated symmetrically to a vertical axis of the deflecting yoke 1 when the current of the toothed wave component flows across the auxiliary coil 6, functions to cancel an ampere turn component which is generated symmetrically to the vertical axis by a horizontal deflection coil 2 disposed asymmetrically to the vertical axis.
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