Color cathode ray tube

A color cathode ray tube comprising:

• an electron gun including an electron beam generating portion arrayed in a horizontal direction for generating three electron beams, and a main lens for focusing said three electron beams from said electron beam generating portion upon a fluorescent face;
• and
• a deflection yoke for scanning said three electron beams upon said fluorescent face;
• said main lens having electrodes with three electron beams passages including a central electron beam passage and side electron beam passages for passing said three electron beams therethrough, said main lens including:
• an accelerating electrode for being supplied with an accelerating voltage;
• a first focusing electrode for being supplied with a first focusing voltage;
• and
• a second focusing electrode for being supplied with a second focusing voltage, said second focusing electrode being near to said accelerating electrode;
• wherein one of the first focusing voltage and the second focusing voltage is a voltage superposed with a dynamic voltage changing according to the deflection of said electron beams;
• and
• wherein an axially asymmetric electron lens is formed between said first focusing electrode and said second focusing electrode, and said axially asymmetric electron lens providing a stronger vertically diverging action at said central electron beam passage of said three electron beam passages than at said side electron beam passages of said three electron beam passages.