| 摘要 |
PURPOSE:To correct the fan-shaped distortion without requiring an expensive auxiliary circuit means, by forming a radial horizontal deflection field and arched vertical deflection field such that the number of turn of the coils in a pair of horizontal deflection oil and a pair of vertical deflection coil are different. CONSTITUTION:A pair of saddle type horizontal deflection coils 7a, 7b and vertical deflection coils 9a, 8b are wound over a troidal core 8 to produce a deflector 5. The number of turn N1 and N2 of the coils 7a and 7b are set such as N2>N1 to form a radial horizontal deflection field 11h where the flux density will increase toward the coil 7b. While the number of turn N1' and N2, of the coils 9a and 9b are set such as N2'>N1' to strengthen the field due to the coil 9b thus to form an arched vertical field 11v. When deflecting the electron beam by the deflection field 11 formed with such horizontal and vertical deflection fields, correctly corrected raster 6 can be formed on the fluorescent face without requiring an expensive auxiliary circuit means resulting in the reduction of the size of a flat picture tube, the lowering of cost and the saving of power. |
