Color picture tube and method for magnetically adjusting the color

Abstract

A color picture tube comprises the vacuumed tube envelope formed by a face plate having a plurailty of phosphor strips regularly formed on the inner surface, a funnel section having an enlarged end opening on which the face plate is mounted a skirt section on which deflection yoke is mounted and neck integrally formed with the funnel section and having located therein an electron gun assembly for emitting electron beams. A shadow mask having a plurality of slits therein is disposed to face to the inner surface of the face plate. The shadow mask is provided on an integral mask frame by which the shadow mask is secured to the inner surface of the tube envelope. The mask frame has an inner shield secured thereto along the inner circumference of the envelope. The inner shield is coupled to a permanent magnet member faced to the inner surface of the envelope. The member is to be preliminarily strongly magnetized and each section thereof is demagnetized and adjusted to a determined value to present a determined intensity of magnetism. The plate serves to change the path of the electron beams, thereby appropriately directing the electron beams toward the determined phosphor strips.