Color cathode ray tube with a dynamic convergence device and color display system employing same

A color display system comprising a color cathode ray tube and a dynamic beam convergence power supply means, said color cathode ray tube comprising:

• an evacuated envelope including a panel portion, a neck portion, and a funnel portion connecting said panel portion to said neck portion;
• a phosphor screen formed on an inner surface of said panel portion;
• a color selection electrode disposed spaced from said phosphor screen in said panel portion;
• an in-line electron gun contained in said neck portion, for generating one center electron beam and two side electron beams and directing said three electron beams toward said phosphor screen;
• a deflection device mounted in the vicinity of a junction between said neck portion and said funnel portion, for deflecting said three electron beams in horizontal and vertical directions and self-converging said three electron beams;
• a static beam convergence means comprising permanent magnets, mounted on said neck portion, for generating an adjustable magnetic field to converge said three electron beams at a central portion of said phosphor screen;
• and
• a dynamic beam convergence means comprising coreless electromagnetic coils, mounted on said neck portion, for generating a magnetic field adjustable to converge said three electron beams at peripheral portions of said phosphor screen;
• wherein said dynamic beam convergence power supply means supplies correction currents in synchronization with deflection of said three electron beams to said dynamic beam convergence means;
• and
• wherein said dynamic beam convergence means comprises at least a third electromagnetic coil means for generating an adjustable magnetic field to move said three electron beams in a same direction.

A color cathode ray tube provided with a convergence correction device provided in a neck portion of said color cathode ray tube, said convergence correction device comprising:

• two cylindrical holder members having large and small diameters, made of an insulating material, held in such a manner as to be coaxial and overlapped on each other;
• and
• a coil member including a plurality of printed coils for generating magnetic fields having an even number of poles contained in a flexible film, said coil member being disposed between said two cylindrical holder members having large and small diameters, respectively;
• wherein a plurality of said printed coils are stacked in said flexible film in such a manner as to be insulated from each other;
• and
• printed coils adjacent to each other and having a same diameter are electrically connected to each other in said flexible film.

A color display system comprising a color cathode ray tube and a dynamic beam convergence power supply means, said color cathode ray tube comprising:

• an evacuated envelope including a panel portion, a neck portion, and a funnel portion connecting said panel portion to said neck portion;
• a phosphor screen formed on an inner surface of said panel portion;
• a color selection electrode disposed spaced from said phosphor screen in said panel portion;
• an in-line electron gun contained in said neck portion, for generating one center electron beam and two side electron beams and directing said three electron beams toward said phosphor screen;
• a deflection device mounted in the vicinity of a junction between said neck portion and said funnel portion, for deflecting said three electron beams in horizontal and vertical directions and self-converging said three electron beams;
• a first magnetic field generating means comprising permanent magnets, mounted on said neck portion, for generating an adjustable magnetic field to move said two side electron beams in opposite directions;
• a second magnetic field generating means comprising permanent magnets, mounted on said neck portion, for generating an adjustable magnetic field to move said two side electron beams in a same direction;
• a third magnetic field generating means comprising permanent magnets, mounted on said neck portion, for generating an adjustable magnetic field to move said three electron beams in a same direction;
• a first electromagnetic coil means comprising coreless electromagnetic coils, mounted on said neck portion, for generating an adjustable magnetic field to move said two side electron beams in opposite directions;
• a second electromagnetic coil means comprising coreless electromagnetic coils, mounted on said neck portion, for generating an adjustable magnetic field to move said two side electron beams in a same direction;
• and
• a third electromagnetic coil means comprising coreless electromagnetic coils, mounted on said neck portion, for generating an adjustable magnetic field to move said three electron beams in a same direction;
• wherein said dynamic beam convergence power supply means supplies correction currents in synchronization with deflection of said three electron beams to said first electromagnetic coil means and said second electromagnetic coil means.

A color cathode ray tube comprising:

• an evacuated envelope including a panel portion, a neck portion, and a funnel portion connecting said panel portion to said neck portion;
• a phosphor screen formed on an inner surface of said panel portion;
• a color selection electrode disposed spaced from said phosphor screen in said panel portion;
• an in-line electron gun contained in said neck portion, for generating one center electron beam and two side electron beams and directing said three electron beams toward said phosphor screen;
• a deflection device mounted in the vicinity of a junction between said neck portion and said funnel portion, for deflecting said three electron beams in horizontal and vertical directions and self-converging said three electron beams;
• a first magnetic field generating means comprising permanent magnets, mounted on said neck portion, for generating an adjustable magnetic field to move said two side electron beams in opposite directions;
• a second magnetic field generating means comprising permanent magnets, mounted on said neck portion, for generating an adjustable magnetic field to move said two side electron beams in a same direction;
• a third magnetic field generating means comprising permanent magnets, mounted on said neck portion, for generating an adjustable magnetic field to move said three electron beams in a same direction;
• a first electromagnetic coil means comprising coreless electromagnetic coils, mounted on said neck portion, for generating an adjustable magnetic field to move said two side electron beams in opposite directions;
• a second electromagnetic coil means comprising coreless electromagnetic coils, mounted on said neck portion, for generating an adjustable magnetic field to move said two side electron beams in a same direction;
• and
• a third electromagnetic coil means comprising coreless electromagnetic coils, mounted on said neck portion, for generating an adjustable magnetic field to move said three electron beams in a same direction.

A color cathode ray tube having a beam deflection yoke and provided with a convergence correction device in a neck portion of the color cathode ray tube, the convergence correction device comprising:

• a cylindrical holder member formed separately from the deflection yoke;
• a coil member including a plurality of printed coils formed of spiral coil conductors for generating magnetic fields having an even number of poles and contained between nonmagnetic insulating films, the coil member being disposed on an inner surface of the cylindrical holder member;
• and
• a plurality of magnetic rings for generating magnetic fields having an even number of poles, the plurality of magnet rings being rotatably mounted around an outer surface of the cylindrical holder member.