Color cathode ray tube having an improved first grid electrode

Abstract

A color cathode ray tube includes a panel portion having a phosphor screen on its inside surface and suspending a shadow mask hanged closely spaced from the phosphor screen, a neck portion for housing an electron gun, and a funnel portion for connecting the panel portion to the neck portion. The electron gun is composed of a first plurality of grid electrodes spaced specified distances apart and arranged axially in a specified order, respectively, and fixed by insulating rods embedding the first plurality of grid electrodes therein, including a cup-shaped first grid electrode having a second plurality of in-line electron beam apertures in a bottom thereof and having the second plurality of cathodes incorporated therein. The cup-shaped first grid electrode is embedded in the insulating rods through metal tabs fixed thereto, and a thermal expansion coefficient T1 of the metal tabs and a thermal expansion coefficient T2 of the cup-shaped first grid electrode satisfy the following inequality, T1>T2.

Dependencies are inferred from the claim text.