JPS5828161A - Color braun tube and its manufacture - Google Patents

Abstract

PURPOSE:To improve the tolerance of phosphor dots around the periphery of a panel by carrying out exposure while rotating a light source installed in water so as to form elliptical phosphor dots. CONSTITUTION:A light source 2 such as a superhigh-pressure mercury-arc lamp which is held in water is installed inside a lamp house 3, and the lamp house 3 is located at a shaft receiving part 4 of a box 1 so that the lamp house 3 can be rotated with a driving motor 5. On the other hand, a panel 6 provided with a shodow mask 10 is positioned at a plate 7 located at the top of the box 1, and a correction lens 6 and a filter 9 are installed between the panel 6 and the light source 2. After that, elliptical phosphor dots, which have a shorter diameter extending in the radial direction of the panel 6 and a longer diameter extending the tangential direction of the panel 6, are formed by rotating the light source 2 by 180 deg.. As a result, the tolerance of the above phosphor dots to an electron beam spot in the peripheral part of the panel 6 can be improved, and the color purity and the manufacturing yield of a Braun tube can be increased.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a color cathode ray tube and a method for manufacturing the same, and more particularly to a color cathode ray tube having a dot-shaped phosphor surface and an exposure method used to form the phosphor surface.

Conventionally, this type of phosphor surface was exposed using a continuous point light source and rotating. Therefore, the light spot formed on the fluorescent surface has the same shape as the hole in the shadow mask, and as a result, the position and shape of the fluorescent surface dots are different from the irradiation position and shape of the electron beam, especially in the periphery of the panel. It is difficult to adjust the f9J angle of the deflection yoke in the subsequent process.

The present invention has been made to overcome these drawbacks of the prior art, and its purpose is to provide a dot-shaped fluorescent light (3) that has a large tolerance in position and shape with respect to the electron beam spot. Another object of the present invention is to provide a color cathode ray tube that can improve color purity and manufacturing yield, and a method for manufacturing the same.

In order to achieve such an object, the present invention provides a negative type dot phosphor surface having phosphor dots with a diameter smaller than the electron beam diameter. This is an elliptical shape with a major axis, and this is symmetrical with respect to the rotation axis (1).
, and has a longitudinal direction perpendicular to the rotation axis, and is formed by exposure while rotating a rotating light source located underwater by 180 degrees or more. Hereinafter, the color cathode ray tube according to the present invention and its lifespan and usage method will be explained in detail using Examples.

FIG. 1 is an explanatory diagram showing a fluorescent surface in an embodiment of a color cathode ray tube according to the present invention. As shown in the figure, the dots of each color phosphor that make up the phosphor surface? Dtff,
The panel has an elliptical shape with a short axis in the radial direction and a long axis in the tangential direction, and while it is almost perfectly circular at the center of the panel, it becomes flatter as it moves away from the center. .

For the fluorescent surface of the color cathode ray tube having the above configuration,
Electron gun #'i is located at the geometric center. Therefore, the landing of the electron beam emitted from the electron gun tends to shift in the axial direction of the panel 2. Therefore, when the phosphor dot has an elliptical shape with a short axis in the radial direction, as shown in FIG. This means that the tolerance can be made larger than when the drum (D) does not have such a flat shape.

Such a fluorescent surface can be formed as follows using an apparatus as shown in FIG.

That is, FIG. 3 shows an example of an exposure apparatus used for manufacturing a color cathode ray tube according to the present invention. In the figure, a light source section consisting of a light source 2 consisting of an ultra-high-pressure water recording lamp and a two-amp house 3 for holding and fixing the light source 2 is arranged in the lower part of the interior of the device housing 1. This light source section is arranged on a rotating table equipped with a bearing section 4 and a drive motor 5 for rotating the light source section. A panel 6 is positioned and mounted on the play 1-7, and a correction lens 8 and a filter 9 are arranged between the wrinkle panel 6 and the light source section. Further, a shadow mask 10 is attached to the panel 6.

Here, the light source 2 has a light emitting section 2 as shown in FIG.
A and an outer tube 2b, and a shield plate 2c is added to the outer tube of the outer tube 2b. Therefore, substantially, the nine portions of the opening facing the panel 6 function as exposure light sources, and this portion is symmetrical with respect to the rotation axis t of the rotary table. and has a long axis perpendicular to the rotation axis t.

Further, the chamber of this light source 2 is filled with water 11 for cooling. In addition, in the same figure, 3a is a glass plate provided on the surface facing the panel 6 of the lamp house 3 of FIG. 2. In addition, in the same figure (, ), (1)), the light sources 2 are connected to each other at 9
0 Shows nine cases viewed from different directions.

In the exposure apparatus having the above configuration, 900. The light emitted from the part l#! ! exposes the inner surface of the panel 6 through a correction lens 8 and a filter 9, and further through a shadow mask 10. In this case, as shown in FIG.
The light 1s emitted has a refractive index of approximately 1.343 and 1
．． The light passes through the water 11 of 469 and the glass plate 3a and exits into the air whose refractive index is approximately 1.0. Therefore, when the light source 2 is viewed from one point on the inner surface of the panel 6 as the exposed surface,
The actual center 2m, 2B of the exposure light source is apparently at the top 2
They will be at positions A' and 2B'.

As described above, since the light source 2 is set underwater, the exposure light source appears to be shifted from its original position with respect to the exposed surface of the panel 6, and the shift is caused by the light source 2t-viewer. The direction differs depending on the direction, and its size also differs depending on the viewing direction since it has a rectangular shape long in one direction defined by the substantial exposure light source or the baffle plate 2C.

Figure 5 shows this type of deviation. In the same figure, as shown in (al), the long axis direction of the ray 2 is y 11+
K It appears at a position shifted by 15 μ in the −X direction toward the center O of the panel 6, as indicated by a vector P. Similarly, at point B in the direction corresponding to FIG.
It appears at the 9th position, shifted by 40μ in the y-force direction. At point C, which is located between the two, the distance is shifted by an amount corresponding to the vector sum of P and Q. Next, when the light source 2 rotates with respect to the y-axis and becomes θ=45 as shown in FIG. 5 (bl), point A and point B are and the exposure spot at the 0 point is 25 μ in the +y force direction and 30 μ in the +x force direction as shown by P p Q and R, respectively.
It is shifted by 40μ in the direction of the sum vector of both μ and . Then the fifth
As shown in Figure (C1), when θ=90, the company, 1
'L'l 171 (c 2) shows ↓ sea urchin, point A,
The exposure spots at point B and point 0 are shifted by 40 μ in the +X direction, 15 μ in the −y direction, and 45 μ in the direction of the sum vector of both, as shown by P%Q, respectively. Next, when σ-135 is obtained as shown in FIG. 5(dl), the exposure spots at point A, point B, and point 0 are P%Q and P%Q, respectively, as shown in FIG. 5(d2). As shown by R, there is a shift of 25μ in the -y force direction, 30μ in the -X direction, and 15μ in the direction of the sum vector of both. Furthermore, when #=180°, the exposure spot shift is in the same state as in FIG. 5 (C2).

In this manner, when the light source 2 rotates 180 degrees, the centers of the 14 light spots rotate 360 degrees on the inner surface of the panel, and the amount of deviation from the original position differs depending on the direction.

FIG. 6 shows the exposure intensity distribution according to the total amount of light irradiated at point A 1 while the light source 2 rotates 180 times.
In the radial direction R, (115 times in this case), the exposure intensity distribution changes as shown in (A) to ←), and as a whole, (
An exposure intensity distribution as shown in c) is obtained. On the other hand, the tangential direction Ta (in this case, the y-axis direction is 10")
In this case, the exposure intensity distribution changes as shown in (i) to (e), and as a whole, the exposure intensity distribution as shown in (f) is obtained. Therefore, if f is the intensity of light a necessary to cause a desired change in the photosensitizer, etc. on the inner surface of the panel, then as shown in the same figure (g), the radius b is 2 in the sial direction, and the radius b is in the tangential direction. An elliptical dot having a major axis a is obtained. Similarly, elliptical dots are obtained for the remaining points on the inner surface of the panel. In this case, the value of the ratio a/b of the major axis to the minor axis of the ellipse becomes larger and flattened at the panel periphery, and a substantially circular dot is obtained at the center. Therefore, it is possible to form a phosphor surface having elliptical phosphor dots as shown in FIG.

1. In this case, in order to obtain an elliptical dot as described above, the light source 2 does not need to rotate 360 times, but only needs to rotate 18 times. For this reason, compared to the conventional method of continuous rotation, the supply of high-voltage power and cooling water to the rotating parts becomes a culprit, resulting in 4! ! The structure can be simplified.

The ratio of the minor axis and major axis of the elliptical dot can be controlled by changing the distance from the inner surface of the nozzle of the light source 2 in synchronization with the rotation of the light @2. FIG. 7 shows an example of an exposure apparatus used in such a method.
The same parts as in the figures are given the same symbols, and detailed explanation thereof will be omitted. That is, in Figure 7, the plate cam 1 is located below the rotating shaft.
2 and its drive motor 13 are disposed, and a follower 14 is attached to the tip of the rotating shaft in contact with the plate cam 12. Therefore, the rice cam 12 is rotated at the same time as the rotating shaft rotates 40 times. By moving the light source 2 up and down, the light source 2 can be moved up and down to change its distance from and to the inner surface of the panel 6. In the above-mentioned embodiment, the photosensitive agent applied to the inner surface of the panel for elliptical exposure is a so-called In the slurry method, it is a phosphor slurry, and in the method of forming a phosphor surface by attaching a powdered phosphor using an original adhesive substance that develops tackiness upon exposure to light, it is the photoadhesive substance. There's nothing to say about it.

As explained above, according to the color cathode ray tube and the manufacturing method thereof according to the present invention, by emitting one light while rotating the light source placed in the water, the short axis in the panel radial direction and the long axis f in the tangential direction! :W-shaped elliptical phosphor dots can be formed. Therefore, it is possible to improve the tolerance of the phosphor dots to the electron beam spot, especially in the periphery of the panel, making it possible to improve the color purity and manufacturing yield of cathode ray tubes. have an effect.

[Brief explanation of the drawing]

・＠Figure 1 is an explanatory diagram showing the fluorescent surface in one embodiment of the color cathode ray tube according to the present invention, Figure 2 is an explanatory diagram showing the relationship between the phosphor dots and the electron beam spot, and Figure 3 is an explanatory diagram showing the relationship between the phosphor dots and the electron beam spot.
4 is an explanatory diagram showing the light source section thereof. FIG. 5 is an explanatory diagram showing the relationship between the rotation of the light section and the exposure spot. FIG. 6 is an explanatory diagram showing the relationship between the light profile and the exposed portion, and FIG. 7 is an internal structural diagram showing another target of the exposure apparatus used for carrying out the present invention. D...dot, IB...electron beam spot,
2... Light source, 2a... Luminous tube, 2b...
Outer tube, 2C...Shining plate, 3...Lamp house, 3a...Glass plate, 4...Bearing part, 5...
...Drive motor, 6...Panel, 1G...Shadow mask, 11...Water, 12..., Board cam,
13... Drive v1 motor, t... Rotating shaft. -2, 2', IV Figure 1 Figure 2 Figure 3 Figure 4 (CI) @ Figure 5 Figure 6

Claims (1)

[Claims] 1. In a cathode ray tube equipped with a phosphor surface having phosphor dots with a diameter IJ smaller than the electron beam spot diameter, the phosphor dots have a short diameter in the radial direction of the panel 2; A color cathode ray tube characterized in that it includes elliptical phosphor dots having a major axis in the tangential direction. 2. In a method for manufacturing a color cathode ray tube, in which the phosphor dot formation site on the inner surface of the panel coated with a photosensitizer is exposed by irradiating the panel with light emitted from the light source section through the circular hole of the shadow mask. The light source section is installed on a rotary table having a rotation axis that approximately coincides with a central axis substantially perpendicular to the exposed surface of the panel, and the light source section is provided with a shape that is symmetrical with respect to the rotation axis. A method for manufacturing a color cathode ray tube, characterized in that a light source is provided that is bubbled in the longitudinal direction perpendicular to the rotation axis and is held underwater, and that exposure is performed while rotating the light source part more than 100 degrees around the rotation axis. 3. The method of manufacturing a color cathode ray tube according to claim #I2, wherein the distance of the light source section from the exposed surface is changed by t"% in synchronization with the rotation of the light source section.