JPH06139948A - Color screening electrode for cathode-ray tube - Google Patents

Abstract

PURPOSE:To provide a color screening electrode for a cathode-ray tube, capable of reducing damper shadow without using any special facility, or deteriorating productivity. CONSTITUTION:An aperture grill 21 is so constituted that narrow strip type grid elements 27 are extended between the opposite support members 22 and 23 of a metal frame 26 comprising the members 22 and 23 as a pair and U-shaped elastic members 24 and 25 to support both ends of the members 22 and 23, in such a way as forming many slits (beam penetration holes) at the prescribed pitch. Also, a vibration-proof damper line 29 is extended on the surface of the grid elements 27. In this case, the damper line 29 is laid at an inclined angle between 20 and 30 degrees with the horizontal direction (X-axis direction) of a screen for image display.

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.

[0002]

2. Description of the Related Art FIG. 3 shows a color selection electrode of a color cathode ray tube.
As shown in FIG. 2, a color selection electrode called a so-called aperture grill 1 in which a large number of grid elements are stretched at a predetermined pitch is used. This aperture grill 1
A large number of thin strip-shaped grid elements are provided between the supporting members 2 and 3 of the metal frame 6 composed of a pair of supporting members 2 and 3 facing each other and U-shaped elastic members 4 and 5 supporting both ends thereof. 7 is stretched at a predetermined pitch so as to form a large number of slits (beam transmission holes) 8.

On the surface of the grid element body 7 of the aperture grille 1, the grid element body 7 resonates due to the vibration from the outside to cause the color blurring and suppress the deterioration of the image quality. The damper wire 9 is stretched.

The damper wire 9 is a thin wire made of, for example, a tungsten wire, and is seam-welded to a damper spring (elastic support piece) 10 via a thin ribbon (metal ribbon) 11 made of stainless steel. The damper spring 10 is an aperture. It is fixed to the elastic members 4 and 5 of the grill 1. In this case, the damper line 9 is arranged parallel to the x-axis direction, that is, the horizontal direction of the screen to be displayed.

[0005]

By the way, when the above-mentioned color selection electrode is mounted on the panel of the cathode ray tube, as shown in FIG. 4, the shadow of the damper wire 9, that is, the damper shadow 14 is slightly formed on the panel 15. There is a problem that it appears on the effective screen 16. The reason for this is that the damper line 9 blocks the ultraviolet light exposure when the phosphor screen is manufactured, and the phosphor layer is thinly formed. Further, the damper line 9 blocks the electron beam during operation.
This is because the brightness in the vicinity of is reduced. Therefore, in order to reduce the damper shadow 14, the following method has been conventionally used. 1) A method of reducing the diameter of the damper wire 9. 2) A method in which the position of the damper wire 9 is moved before and after the production of the phosphor screen (see, for example, JP-A-61-240531). 3) A method of increasing the rigidity of the grid element body 8 itself to eliminate the need for the damper wire 9.

However, the above methods 1) to 3) have the following problems. That is, in the method 1), the breaking strength of the damper wire 9 becomes low, so that the damper wire 9 may be cut in the manufacturing process of the cathode ray tube and in the market. Although the method 2) is used in some pipe types, it requires special parts and equipment for moving the damper wire 9, resulting in increased cost and reduced productivity. Furthermore, in the method of 3), about 500 to 100
Since it is necessary to reinforce all zero grid element bodies 8, the productivity is deteriorated.

The present invention has been made in view of the above points of the conventional example, and an object thereof is to reduce damper shadow without using special equipment and without deteriorating productivity. It is to provide a color selection electrode for a cathode ray tube.

[0008]

According to the present invention, for example, as shown in FIG. 1 or 2, a large number of strip-shaped grid elements 27 are stretched on a metal frame 26, and the grid elements 27 vibrate. In the color selection electrode 21 of the cathode ray tube in which the damper line 29 for prevention is stretched, the damper line 29 is arranged obliquely with respect to the horizontal direction (x-axis direction) of the screen 34 to be displayed. It is what In this case, the damper line 29 should be doubled in the horizontal direction of the screen 34 to be displayed.
It can also be arranged at an angle of 0 ° to 30 °.

[0009]

The resolving power of the human eye has an angle dependence, and lines extending obliquely are harder to recognize than lines extending horizontally and vertically. The present invention has been made paying attention to such a phenomenon, and the damper line 29 is slanted, for example, 20 ° with respect to the horizontal direction (x-axis direction) of the screen 34 to be displayed.
Damper shadow 3
5 is difficult to be recognized by the naked eye.

[0010]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT An embodiment of a color selection electrode for a cathode ray tube according to the present invention will be described below with reference to the drawings.

FIG. 1 shows the entire aperture grill 21 which is a color selection electrode of this embodiment. In the present embodiment, the pair of supporting members 22 and 23 facing each other and the supporting member 22 of the metal frame 26 composed of the U-shaped elastic members 24 and 25, which are hollow pipes having a circular cross section, for supporting both ends thereof. A large number of thin strip-shaped grid elements 27 are stretched over the gaps 23 and 23 with a predetermined pitch so as to form a large number of slits (beam transmission holes).

Then, a damper wire 29 for preventing vibration, which will be described later, is stretched on the surface of the grid element body 27, and damper springs 30 preliminarily attached to both ends of the damper wire 29.
The ends of are fixed to the elastic members 24 and 25 by spot welding, respectively.

On the other hand, the support members 22 and 23 and the elastic member 2
Holders 32 are welded to 4 and 25, respectively, and a support spring 33 for supporting the aperture grill 21 on the panel P is welded on each holder 32.

As shown in FIG. 1, in the present embodiment,
The damper springs 30 are arranged so as to be offset from the centers of the elastic members 24 and 25 in opposite directions, so that the damper lines 29 are arranged obliquely with respect to the x-axis direction, that is, the horizontal direction of the screen to be displayed. That is, as shown in FIG. 2, the damper shadow 3 appearing on the effective screen 34 of the panel P.
5 is oblique to the horizontal line 36. In this case, it is preferable that the inclination angle θ between the damper shadow 35 and the horizontal line 36 is 20 ° to 30 °.
The inclination angle θ may be either clockwise or counterclockwise.

According to this embodiment having such a configuration, the damper shadow 35 can be made inconspicuous for the following reasons. That is, the resolving power of the human eye has angle dependence, and a line extending obliquely with respect to the horizontal direction is harder to recognize than a line extending horizontally or vertically. In particular, the direction that forms an angle of 45 ° with the horizontal direction is the most difficult to recognize. Therefore, set the damper wire 29 to the horizontal line 3
The damper shadow 35 becomes the most inconspicuous if it is attached at an angle of 45 ° with respect to 6. However, in the normal case,
Since the effective screen 34 of the panel P has a horizontally long shape, and the color selection electrodes are also configured corresponding to this, the damper wire 2
The smaller the inclination angle θ of 9 with respect to the horizontal line 36, the easier the design. On the other hand, as described below, if the inclination angle θ is 20 ° or more, the damper shadow 35 can be sufficiently reduced.

Next, the visibility of the damper shadow 35 or 14 was tested using the color selection electrode of this embodiment and the conventional color selection electrode. That is, the screen of the cathode ray tube incorporating this embodiment and the screen of the cathode ray tube incorporating the conventional example are shown to the subject at the same time, and the damper shadow 35 or 1 is displayed.
I checked the percentage of people who found 4. In this case, the inclination angle θ of the damper wire 29 in this embodiment was 20 °, and a 20-inch size normal tube was used in both this embodiment and the conventional example. All subjects were damper shadow 35 or 1.
Targeted at non-technical persons who do not know the existence of 4. The test results are shown in Table 1.

[0017]

[Table 1]

As can be seen from Table 1, it was found that the damper shadow 35 is less noticeable when the color selection electrode of this embodiment is used for any signal.

The present invention is not limited to the above-described embodiments, but various modifications can be made within the scope of the present invention. For example, the mounting position of the damper spring can be changed according to the pipe type. Further, it is possible to provide a plurality of damper wires, and in that case, the damper wires can be crossed. Further, the present embodiment can be combined with a conventional method such as thinning the damper wire.

[0020]

As described above, in the present invention, the damper line is slanted with respect to the horizontal direction of the screen to be displayed,
For example, since they are arranged at an angle of 20 ° to 30 °, the damper shadow can be reduced without using special equipment and without deteriorating the productivity.

[Brief description of drawings]

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

FIG. 2 is an explanatory diagram showing a damper shadow of the same embodiment.

FIG. 3 is a perspective view of a conventional color selection electrode.

FIG. 4 is an explanatory diagram of a conventional damper shadow.

[Explanation of symbols]

 21 Aperture grill 22,23 Support member 24,25 Elastic member 26 Metal frame 27 Grid element body 29 Damper line 34 Effective screen 35 Damper shadow 36 Horizontal line

Claims (2)

[Claims] 1. A color selection electrode for a cathode ray tube, comprising a plurality of strip-shaped grid elements stretched over a metal frame, and vibration-damping damper wires stretched over the grid elements. Is arranged obliquely with respect to the horizontal direction of the screen to be displayed. 2. The color selection electrode for a cathode ray tube according to claim 1, wherein the damper wire is arranged at an angle of 20 ° to 30 ° with respect to the horizontal direction of the screen to be displayed.