| 摘要 |
PURPOSE: Cathode-ray tube apparatus is provided to reduce a difference between a focusing power of a lens function acting on a center beam and a focusing power of a lens function acting on side beams, thus obtaining a uniform and high resolution over the entire area of a screen. CONSTITUTION: A cathode-ray tube apparatus includes an electron gun assembly(7) having an electron beam generating section and a pair of side beams, and a main lens section, and a deflection yoke. The main lens section comprises a focus electrode, to which a focus voltage of a first level is applied, an anode, to which an anode voltage of a second level higher than the first level is applied, and at least one intermediate electrode which is disposed between the focus electrode and the anode and to which a voltage of a substantially intermediate level between the first level and the second level is applied. The focus electrode has, in a first end face thereof opposed to the intermediate electrode, three electron beam passage holes for passing the three electron beams. The asymmetric lens section is created at a position away by a distance or less, which corresponds to a diameter of the electron beam passage hole formed in the first end face, from the first end face of the focus electrode toward the electron beam generating section, the asymmetric lens section having an asymmetry of a lens function acting on the center beam, which differs from an asymmetry of a lens function acting on the side beams.
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