JPH0696683A - Color screening electrode for color cathode-ray tube - Google Patents

Abstract

PURPOSE:To prevent a fluorescent stripe to be broken due to narrowed opening breadth by forming a metal filament body at the outermost side of the electrode plate of an extension type color screening electrode in such a way that the breadth of the body at both lengthwise ends becomes larger than that at a center section. CONSTITUTION:An electrode base 9 is extended with many metal filaments 2 and a outermost metal filament body 3 arranged in a frame 1 having an window frame form. The metal filament body 3 is sized so that breadth d1 at both lengthwise ends and breadth d2 at a center section satisfy a relationship of d1>d2. A change in breadth from d1 to d2 should preferably be made as gradual as possible. As a result, a component other than a lengthwise component is reduced, regarding stress occurring within the plane of the metal filament body 3. According to this construction, a trouble can be eliminated, such the break of a phosphorus stripe due to narrowed opening breadth, because of the metal filament body 3 nearing the inner filaments 2.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a color selection electrode for a color cathode ray tube, and more particularly to a stretchable color selection electrode for applying tension to an electrode plate.

[0002]

2. Description of the Related Art A conventional stretchable color selection electrode is a window composed of a pair of frame sides 4 and 5 and a pair of arm portions 6 and 7 connecting the frame sides 4 and 5 as shown in FIG. Frame-shaped frame 1
The electrode plate 9 having a plurality of metal strips 2 arranged at a predetermined pitch on the
It has a configuration in which The color selection electrode 8 is also used as a photomask when the fluorescent film surface of the color cathode ray tube is formed by the photolithography method, but it blocks unnecessary light rays during exposure to clearly define an effective screen and unnecessary portions. For the sake of distinction, the outermost side of the electrode plate 9 is formed as a metal strip 3 wider than the other metal strips 2 (see, for example, Japanese Patent Publication No.
4-13417). When the electrode plate 9 is stretched, first, a compressive force is applied to the outside of the frame sides 4 and 5 of the frame 1 to compress it, and the electrode plate 9 is fixed to the frame sides 4 and 5 while maintaining this state. After that, when the compressive force is removed, the restoring force of the frame 1 applies tension to the metal strips 2 and the metal strips 3 of the electrode plate 9.

[0003]

By the way, in the conventional color selection electrode, since the width of the outermost metal strip is not negligible as compared with other metal strips, the in-plane stress as shown by the arrow in FIG. 5 is generated. Occur. As a result, the metal strip approaches the metal strip and the outermost opening is narrowed, so that when the fluorescent film surface is formed, the amount of exposure light passing through this opening is insufficient and the phosphor stripe is interrupted. To eliminate this drawback,
There is also a proposal to widen the distance between the outermost metal strip and the metallic strip in advance (for example, Japanese Examined Patent Publication No. 50-4430), but this causes other drawbacks such as the outermost stripe trios overlapping each other.

[0004]

DISCLOSURE OF THE INVENTION The present invention provides a color cathode line in which a large number of metal strips are arranged on a window frame-shaped frame at a predetermined pitch and an electrode plate having metal strips arranged on the outermost side is stretched. In the stretchable color selection electrode for a tube, the width of both end portions of the metal strip in the longitudinal direction is made larger than the width of the central portion.

[0005]

The present invention will be described below with reference to the drawings. FIG. 1 is a perspective view of the first embodiment of the present invention. An electrode plate 9 having a large number of metal strips 2 and an outermost metal strip 3 arranged on a window-frame-shaped frame 1 is stretched. In this embodiment, the outermost metal strip 3 has a width d at both ends in the longitudinal direction.
1, d1> d2, where d2 is the width at the center. The change from the width d1 to d2 should be made as smooth as possible. That is, when the coordinate axes are taken as shown in FIG. 2, it is desirable to use a quadratic function of y or a hyperbolic function. Array pitch of metal strips is 0.4m
When m, the width is 0.3 mm, and the length is 400 mm, d1 =
7 mm, d2 = 6.5 mm, x = 1.25 × 10 ⁻⁵ y ²
When, the deformation of the outermost opening was minimized.

FIG. 3 is a perspective view of a second embodiment of the present invention. In this embodiment, the width d1 at both ends to the width d in the central portion are shown.
It changes linearly to 2. This embodiment has a simple structure suitable for a small size of the color selection electrode.

[0007]

As described above, according to the present invention, the shape of the outermost metal strip of the electrode plate of the stretchable color selection electrode is such that the width at both ends in the longitudinal direction is wider than that at the center. As a result, of the stress generated in the plane of the metal strip, components other than those in the longitudinal direction are reduced. Therefore, it is possible to solve the problem that the metal strip is close to the inner metal strip, the opening width is narrowed, and the fluorescent stripe is interrupted. Further, since it is not necessary to widen the space between the metal strip and the metal strip in advance, problems such as phosphor stripe trio overlapping will not occur.

[Brief description of drawings]

FIG. 1 is a perspective view of a stretchable color selection electrode according to a first embodiment of the present invention.

FIG. 2 is a top view of the right side portion of FIG.

FIG. 3 is a perspective view showing a second embodiment of the present invention.

FIG. 4 is a perspective view of a conventional stretchable color selection electrode.

FIG. 5 is a diagram for explaining that the metal strip of the conventional stretchable color selection electrode is close to the metal strip.

[Explanation of symbols]

 1 frame 2 metal strip 3 metal strip 4 frame side 5 frame side 6 arm 7 arm 8 color selection electrode 9 electrode plate

Claims (1)

[Claims] 1. A stretchable color selection electrode for a color cathode ray tube in which a large number of metal strips are arranged at a predetermined pitch on a window frame and an electrode plate on which metal strips are arranged on the outermost side is stretched. 2. The color selection electrode for a color cathode ray tube according to claim 1, wherein the width of both ends of the metal strip in the longitudinal direction is larger than the width of the central portion.