Patent ID: 6924589

Claim:
A color picture tube device that deflects a plurality of electron beams and produces a color image on a phosphor screen, comprising: an electron gun which has a plurality of in-line cathodes and emits the plurality of electron beams; a deflection yoke which includes a horizontal deflection coil generating a horizontal deflection magnetic field, a vertical deflection coil generating a vertical deflection magnetic field, and a core; a quadrupole magnetic field generation unit which generates, between the phosphor screen and an end of a deflection region facing the electron gun, a quadrupole magnetic field having a vertical component and a horizontal component, the vertical component causing the plurality of electron beams to move toward or away from each other in a horizontal direction, the deflection region being where the horizontal and vertical deflection magnetic fields have deflection effects, the quadrupole magnetic field generation unit includes a core piece and a first wire wound around the core piece; and an auxiliary magnetic field generation unit which generates an auxiliary magnetic field for canceling out at least a part of the horizontal component of the quadrupole magnetic field, according to vertical deflection of the plurality of electron beams by the vertical deflection magnetic field, the auxiliary magnetic field generation unit includes a second wire wound around the core piece, the core piece, the first wire, and the second wire from a magnetic coil, and a magnetic flux generated by supplying a current to the second wire has an opposite direction to a direction of a magnetic flux generated by supplying a current to the first wire, wherein the quadruple magnetic field generation unit generates a magnetic flux that forms the quadrupole magnetic field, and when the plurality of electron beams are vertically deflected, the auxiliary magnetic field generation unit generates a magnetic flux which cancels out a part of the magnetic flux that is generated by the quadrupole magnetic field generation unit on one of upper and lower sides of a horizontal center line of the quadrupole magnetic field to which the plurality of electron beams are vertically deflected.