Braun color cathode ray tube having shadow mask horizontal pitch novelty
AssigneeHitachi, Ltd.
InventorsYuichi Inoue, Katsuyoshi Tamura
Life of this patent
Estimating the term…
Abstract
A Braun tube for use in a TV receiver or the like, in which its screen does not need high resolution, but the brightness of the screen is important. The Braun tube has a panel with a flat outer surface, an electron gun arranged in an in-line manner and a phosphor screen whose phosphors are arranged in a delta pattern, and the horizontal pitch of a shadow mask can be varied in the direction of the Y-axis. The mechanical strength of the shadow mask is improved by making the curvature of the shadow mask larger than the curvature of the inner surface of the panel in the direction of the vertical axis of the screen.
Claims21
A color picture tube comprising:
- a panel having an outer panel surface whose equivalent radius of curvature taken in the direction of its Y-axis is 10,000 mm or more, and an inner panel surface whose equivalent radius of curvature is smaller than the equivalent radius of curvature of the outer panel surface in the directions of its X-axis, the Y-axis and its diagonal axes;
- delta type phosphors formed on the inner panel surface;
- a press forming type of shadow mask being opposed to the inner panel surface and having multiple apertures arranged at a horizontal pitch Pmh and a vertical pitch Pmv, the horizontal pitch being larger by 5% or more at an end of a shorter axis of an effective surface of the shadow mask than in the center of the shadow mask, the horizontal pitch being 0.6 mm or more, and Pmh<{square root over ( )}3Pmv;
- and
- an electron gun arranged in an in-line manner.
A color picture tube comprising:
- a panel having an outer panel surface whose equivalent radius of curvature taken in the direction of its Y-axis is 10,000 mm or more, and an inner panel surface whose equivalent radius of curvature is smaller than the equivalent radius of curvature of the outer panel surface in the directions of its X-axis, the Y-axis and its diagonal axes;
- delta type holes of a black matrix formed on the inner panel surface, phosphors being formed in the respective holes and the distance between adjacent ones of the holes being the smallest in the horizontal direction;
- a press forming type of shadow mask being opposed to the inner panel surface and having multiple apertures, the horizontal pitch of the apertures being larger in a periphery of the shadow mask than in the center of the shadow mask, the horizontal pitch in the center of the shadow mask being 0.6 mm or more;
- and
- an electron gun arranged in an in-line manner.
A color picture tube comprising:
- a panel having an outer panel surface whose equivalent radius of curvature taken in the direction of its Y-axis is 10,000 mm or more, and an inner panel surface whose equivalent radius of curvature is smaller than the equivalent radius of curvature of the outer panel surface in the directions of its X-axis, the Y-axis and its diagonal axes;
- delta type phosphors formed on the inner panel surface;
- and
- a press forming type of shadow mask being opposed to the inner panel surface and having multiple apertures having a horizontal pitch and a vertical pitch, the horizontal pitch in the center of the shadow mask being 0.6 mm or more,
- letting Pmhc and Pmhd be, respectively, the horizontal pitch in the center of the shadow mask and the horizontal pitch in each diagonal-axis end portion of an effective surface of the shadow mask, Pmhd≧1.5Pmhc;
- and
- an electron gun arranged in an in-line manner.
Dependencies are inferred from the claim text.