Cathode-ray tube apparatus

A cathode-ray tube apparatus comprising:

• an electron gun assembly including,
• an electron beam generating section which generates electron beams, and
• a main lens which focuses the electron beams generated by the electron beam generating section on a phosphor screen;
• and
• a deflection yoke which generates deflection magnetic fields that horizontally and vertically deflect the electron beams emitted from the electron gun assembly,
• wherein the electron gun assembly includes at least one multi-polar lens that is created in accordance with deflection of the electron beams,
• said at least one multi-polar lens is created by two mutually opposing grids,
• said two mutually opposing grids including non-circular electron beam passage holes in their mutually facing surfaces, and wherein
• each of the electron beam passage holes in one of the grids that create the multi-polar lens has a waist portion that minimizes a horizontal dimension of a region for passing the associated electron beam, and each of the electron beam passage holes in the other of the grids that create the multi-polar lens has a waist portion that minimizes a vertical dimension of the region for passing the associated electron beam.

A cathode-ray tube apparatus comprising:

• an electron gun assembly including,
• an electron beam generating section which generates electron beams, and
• a main lens which focuses the electron beams generated by the electron beam generating section on a phosphor screen;
• and
• a deflection yoke which generates deflection magnetic fields that horizontally and vertically deflect the electron beams emitted from the electron gun assembly,
• wherein the electron gun assembly includes at least one multi-polar lens that is created in accordance with deflection of the electron beams,
• said at least one multi-polar lens is created by two mutually opposing grids,
• said two mutually opposing grids including non-circular electron beam passage holes in their mutually facing surfaces,
• each of the electron beam passage holes including a waist portion which minimizes a horizontal or vertical dimension of a region for passing the associated electron beam, and wherein
• said multi-polar lens comprises a quadrupole lens having a horizontal focusing function and a vertical diverging function, and these lens functions vary in accordance with deflection of the electron beams.

A cathode-ray tube apparatus comprising:

• an electron gun assembly including,
• an electron beam generating section which generates electron beams, and
• a main lens which focuses the electron beams generated by the electron beam generating section on a phosphor screen;
• and
• a deflection yoke which generates deflection magnetic fields that horizontally and vertically deflect the electron beams emitted from the electron gun assembly,
• wherein the electron gun assembly includes at least one multi-polar lens that is created in accordance with deflection of the electron beams,
• said at least one multi-polar lens is created by two mutually opposing grids,
• said two mutually opposing grids including non-circular electron beam passage holes in their mutually facing surfaces,
• each of the electron beam passage holes including a waist portion which minimizes a horizontal or vertical dimension of a region for passing the associated electron beam, and wherein
• said multi-polar lens comprises a quadrupole lens having a horizontal diverging function and a vertical focusing function, and these lens functions vary in accordance with deflection of the electron beams.