| 摘要 |
PROBLEM TO BE SOLVED: To provide a high quality flat face color cathode ray tube with a tint panel combined with a press mask. SOLUTION: The outer face of a panel of the color cathode ray tube is formed approximately flat and the inner face is curved into recessed face. The longitudinal pitch of slots formed in a perforated region 2 of the press mask 1 arranged in proximity to the inner face and the connection width of bridges connecting the slots are differentiated at a central portion (A) of the perforated region 2 of the press mask 1 from those at a peripheral portion (B). The percentage of the bridges occupied per unit area is larger at the central portion (A) than at the peripheral portion (B), or the percentage of the slots opened per unit area is larger at the peripheral portion (B) than at the central portion (A). Thus, the mechanical strength of the press mask is greater at the central portion (A), inhibiting the undersired deformation of the press mask 1 due to a so-called doming phenomenon resulting from the application of external impulse or temperature rise with the increase of the radius of curvature of the central portion (A) and permitting the uniform brightness all over the screen.
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