| 摘要 |
PROBLEM TO BE SOLVED: To reduce deterioration in brightness and unevenness, in the periphery of a screen and increase the purity margin, regardless of the direction of the face panel of a color cathode-ray tube. SOLUTION: The passage hole diameter of the electron beam in a periphery 6A of a perforated area AR is made smaller than the passage hole diameter of the electron beam at the end portions of a main part 6B located adjacent in the central direction, and the passage hole diameter of the electron beam in the main part 6B is made larger in the periphery than at the center.
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