| 摘要 |
PURPOSE:To obtain a cathode-ray tube having a glass panel excellent in mechanical strength by providing the specific relations in the thickness of glass among the vertical axis direction, horizontal axis direction and diagonal axis direction near the substantially rectangular frame of the glass panel face part. CONSTITUTION:The thickness tv, tH and tD near the rectangular frame in the respective directions of the face part are constituted so as to have the relations tv>=tH and tD>=tH. In order to constitute the thickness near the rectangular frame in the respective axial directions of the face part in this way, it is effective to make the outer surface radiuses of curvature Rv, RH and RD as well as the inner surface radiuses of curvature R'v, R'H and R'D in the respective axial directions of the face part, X in such relations as Rv<=RH<=RD, and R'v<=R' and also R'D<= R'H. Or, it is also effective to make Rv>=RH further RD>=RH and R'v>=R'H>= R'D. Thereby, since the thickness of the upper end in the screen vertical axils direction, in which mechanical expansion stress due to the atmospheric pressure becomes maximum, is formed sufficiently large, sharply improved mechanical strength can be obtained. |
