Cathode ray tube equipment

Abstract

An electron gun assembly in a cathode-ray tube apparatus includes a quadrupole lens that is created in accordance with deflection of electron beams. The quadrupole lens is created by two mutually opposing grids. The two grids have non-circular electron beam passage holes in their mutually facing surfaces. Each electron beam passage hole has a waist portion which minimizes a horizontal or vertical dimension of a region for passing the associated electron beam.

Description

technical field [0001] The present invention relates to a cathode ray tube device, in particular to a color cathode ray tube device which reduces beam spot ellipse distortion at the periphery of a fluorescent screen and displays high-quality images. Background technique [0002] A general color cathode ray tube device has an in-line electron gun unit that emits three electron beams arranged in-line in the horizontal direction, and a deflection yoke that generates a non-uniform deflection magnetic field that deflects the three electron beams in the horizontal and vertical directions. . QPF (Quadru-Potential Focus, four-position focus) type double-focus electron gun component as an electron gun component emitting three electron beams, such as Figure 8 As shown, there are three cathodes K arranged in line and six grids G1 to G6 arranged in sequence toward the fluorescent screen. Each of the grids G1 to G6 has three electron beam passing holes corresponding to the three cathod...

AI Technical Summary

Problems solved by technology

[0021] However, when forming the partition-like protruding part, in consideration of productivity, it is necessary to use shearing and bending by pressing.

These processes have poorer dimensional accuracy than hole drilling.

Therefore, it is difficult to improve the dimensional accuracy when forming the spacer-shaped protruding part, resulting in a difference in the strength of the quadrupole lens or an undesired electron beam deflection effect, etc., which cause a difference in focusing performance and deterioration

In addition, due to the structure protruding in the electron beam advancing direction, there is also a disadvantage that the length of the grid in the electron beam advancing direction cannot be shortened, and the degree of freedom in the design of the electron gun components is limited.

An additional disadvantage is the increased cost due to the increased part count

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