Patent ID: 6841927
Filing Date: 2005-01-11
Classification: H01J

Abstract:
1. A flat color cathode ray tube including a vacuum envelope composed of a panel, a funnel, and a neck, the panel having a generally flat outer surface and a convex inner surface having a curvature with respect to an axis of the cathode ray tube, the inner surface having an effective surface on which a phosphor screen is formed, a grill or stripe-type mask being opposed to the inner surface of the panel and extended in a vertical direction, wherein in an equation F=Rdo/(Sd×1.767), conditions of F>21, Tc/CFT≦1.35, and Rdi>(Ryi or Rxi) are satisfied, where Sd is a length of a diagonal effective picture of the panel, Rdo is a curvature radius of a diagonal outer surface, Ryo is a curvature radius of a vertical outer surface, Rxi, Ryi and Rdi are a horizontal, vertical and diagonal curvature radius, respectively, CFT is a thickness of a center portion, Tc is a thickness of a diagonal end of the effective surface, F is a planarizing rate of the outer curvature.