| 摘要 |
PURPOSE: A color cathode ray tube having a flat outer face is provided to achieve improved mechanical strength of a shadow mask by changing radius of curvature to a linear shape. CONSTITUTION: A panel(1) has a flat outer surface with an equivalent radius of curvature of 10,000mm or higher in a diagonal axis direction, and a curved inner surface which is formed convex toward the outer surface of the panel. A shadow mask(5) is opposed to the inner surface of the panel, and has an approximately rectangular shape. The radius of curvature of the shadow mask is approximately linearly decreased toward the periphery of the shadow mask rather than the center of the shadow mask. To make the change of radius of curvature caused due to the distance measured from the center of the shadow mask on the diagonal axis, to be approximate to a line by the least square method, the difference between the radius of curvature and the line in each position is kept 100mm or lower.
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