Cathode-ray tube apparatus having a reduced leak of magnetic fluxes

A cathode-ray tube apparatus wherein unwanted leakage magnetic fluxes are controlled, comprising;

• an envelope having an axis and comprising a panel having a face plate and a skirt attached to the face plate, a funnel connected to the skirt of the panel, and a neck extending from the funnel;
• an electron gun assembly located within said neck, for emitting electron beams;
• a screen formed on said face plate, for producing light rays when irradiated with the electron beams;
• horizontal deflection means mounted on said funnel and having a curved front section and a rear section, the front section located at a screen side of said horizontal deflection means and said rear section located at an electron gun assembly side of said horizontal deflection means, said horizontal deflection means for generating deflection magnetic fields which deflect the electron beams in a horizontal direction, and horizontal deflection means also generating leakage magnetic fluxes outside said envelope;
• and
• closed loop conductor means extending along the skirt of said panel, along said funnel toward said horizontal deflection means, including a section curved along the curved front section of the horizontal deflection means and directly mounted on the curved front section, and crossing the leakage magnetic fluxes generated by the curved front section, said leakage magnetic fluxes inducing a current in said closed loop conductor resulting in compensating magnetic fluxes, said compensating magnetic fluxes controlling said leakage magnetic fluxes, said closed loop conductor located such that said compensating magnetic fluxes do not adversely affect said deflection magnetic fields.

A cathode-ray tube apparatus for suppressing leakage magnetic flexes, comprising:

• electron beam emitting means for emitting at electron beam;
• light ray producing means for producing light rays when irradiated with said electron beam;
• an envelope having an axis and enclosing said electron beam emitting means and said light ray producing means;
• deflecting magnetic field generating means, located on said envelope and having a front and rear edge section, for generating and applying effective magnetic fluxes in said envelope to deflect the electron beam in a horizontal direction, and also generating first and second leakage magnetic fluxes extending in a direction different from that of said effective magnetic fluxes, the first leakage magnetic fluxes being greater in magnitude than said second leakage magnetic fluxes and being substantially distributed between said front edge section and said light ray producing means, and said second leakage magnetic fluxes being substantially distributed between said rear edge section and said electron beam emitting means;
• and
• passive control means, including a pair of closed loops each of which having a portion mounted on said front edge section, for controlling said first and second leakage magnetic fluxes, said pair of closed loops being arranged on said envelope so as to be substantially symmetrical to said axis in order to receive said first leakage magnetic fluxes, whereby a current is electromagnetically induced in each of said closed loops when said first leakage magnetic fluxes are applied to said closed loops, thereby generating compensating magnetic fields from the closed loops.

A cathode-ray tube apparatus for suppressing leakage magnetic fluxes, comprising:

• an envelope having an axis and comprising a panel having a face plate and a skirt attached to said face plate, a funnel connected to said skirt of said panel, and a neck extending from said funnel;
• an electron gun assembly located within said neck, for emitting electron beams;
• a screen formed on said face plate, for producing light rays when irradiated with said electron beams;
• horizontal deflection means mounted on said funnel and having a front and rear edge section, for generating deflection magnetic fluxes to deflect said electron beams in said envelope in a horizontal direction, and also for generating first and second leakage magnetic fluxes in a direction different from that of said deflection magnetic fluxes, said first leakage magnetic fluxes being greater in magnitude than said second leakage magnetic fluxes and being substantially distributed between said front edge section and said screen, and said second leakage magnetic fluxes being substantially distributed between said rear edge section and said electron gun assembly;
• and
• a pair of closed loop conductors arranged so as to be substantially symmetric with respect to said axis;
• each of said conductors extending along said skirt of said panel and also along said funnel toward said horizontal deflection means and having a part located on said front edge section, wherein said conductors cross said first leakage magnetic fluxes, thereby inducing a current to be generated in said conductors and causing compensating magnetic fluxes to be generated.