Electron gun assembly for a color cathode ray tube

A cathode ray tube apparatus having an electron gun assembly including:

• generating means for generating three in-line electron beams on a horizontal plane and controlling and accelerating the electron beams;
• a single main electron lens system for focusing and converting the three electron beams from the generating means, said main electron lens system comprising:
• a single and common large-diameter asymmetric electron lens having different electron lens power in horizontal and vertical directions, the three electron beams being incident on said asymmetric electron lens, each incident beam being more diverged in the vertical plane than in the horizontal plane, and each incident beam being parallel to other beams in the horizontal plane, and
• additional electron lens means for aligning the three beams in a substantially single direction in the horizontal plane and for diverging each electron beams in the vertical plane.

A cathode ray tube apparatus having an electron gun assembly including:

• generating means for generating three in-line electron beams in a horizontal direction and for controlling and accelerating the electron beams;
• and
• a main electron lens system for focusing and converging the three electron beams from said generating means, said electron lens system comprising:
• a first hollow cylindrical electrode structure having, on one open end, an end electrode with apertures, and on the other open end, a first plate electrode with a noncircular hole with a major axis along a horizontal plane perpendicular to said center electron beam, the first plane electrode being distinct and separate from the end electrode;
• a second hollow cylindrical electrode structure, in which a part of the first hollow cylindrical electrode structure is inserted and in which a second plate electrode, with a noncircular hole with a major axis along vertical direction, is placed, the first cylindrical electrode structure being at a lower potential than the second cylindrical electrode structure.

A cathode ray tube apparatus having an electron gun assembly including:

• generating means for generating three in-line electron beams on a horizontal plane and controlling and accelerating the electron beams;
• a single main electron lens system for focusing and converging the three electron beams from the generating means, said main electron lens system comprising:
• a single and common large-diameter asymmetric electron lens having different electron lens power in horizontal and vertical directions, the three electron beams being incident on said asymmetric electron lens, each incident beam being more diverged in the vertical plane than in the horizontal plane, and each incident beam being parallel to other beams in the horizontal plane, and
• additional electron lens means for aligning the three beams in a substantially single direction in the horizontal plane and for diverging each electron beams in the vertical plane, said additional electron lens means having a variable lens power;
• and
• means for deflecting the three electron beams generated from the electron gun assembly in the horizontal and vertical planes, the deflection means generating a convergence free magnetic field,
• wherein said variable lens power of said additional electron lens means controls the degree of divergence of the three electron beams according to degree of deflection by said deflection means.