Color cathode ray tube

摘要

The present invention provides a color cathode ray tube having a shadow mask for selecting colors, wherein the shadow mask satisfies the relation: $5.5<\frac{\mathrm{Rh}}{\left(\frac{H}{2}\right)}<8.0,$ where Rh is a mean curvature radius in the direction of the long axis of the shadow mask, H is a distance between both ends in a direction of a long axis of an effective surface of the shadow mask, and a mean curvature radius in the direction of the long axis satisfies the condition: $\mathrm{Rh}=\frac{{\left(\frac{H}{2}\right)}^2+{\mathrm{Zh}}^2}{2*\mathrm{Zh}}$ where Zh is a recess amount in a direction of a tube axis at an end of the long axis of the effective surface with respect to a center of the effective surface.