JPH1050214A - Exposure method for color cathode-ray tube and its device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To adjust the radiative amount of a phosphor in only a specified region of the tube face. SOLUTION: Ultraviolet radiations emitted from a light source 6 composed of three light sources are incident on the light amount correction filter 10, and are respectively adjusted to proper light amounts. The respective ultraviolet radiations pass through a light source position correction lens 12 and an electron beam locus correction lens 14, and are incident on a photosensitive coating film 18 via an aperture grille 20. The photosensitive coating film 18 is exposed strip-like, and when the unexposed portion of the photosensitive coating film 18 is removed, the photosensitive coating film 18 is left strip-like on the inner face of a face plate 16. A carbon film is uniformly formed thereon, and the photosensitive coating film 18 is decomposing removed so as to form carbon stripes. The intervals of the carbon stripes are locally adjusted by locally adjusting the ultraviolet radiation transmittance of the light amount correction filter 10 so that the radiative light amount of the respective phosphors so as to release chromaticity difference in the specified region of a tube face.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method and an apparatus for exposing a color cathode ray tube, and more particularly, to a method of forming a carbon stripe on the inner surface of a face plate of a color cathode ray tube, as a pre-process. The present invention relates to a method and an apparatus for exposing a photosensitive coating film through a slit of an aperture grill.

[0002]

2. Description of the Related Art FIG. 7 is a flowchart showing a process of manufacturing a conventional color cathode ray tube. As shown in this flowchart, in manufacturing a color cathode ray tube, first, a phosphor screen is formed on the inner surface of the face plate (step S1), and then the face plate and the main body of the color cathode ray tube are joined in a frit seal furnace (step S1). S2) After the electron gun is further sealed (Step S3), exhaust is performed to a required degree of vacuum (Step S4). Subsequently, after performing aging and explosion-proof processing sequentially (steps S5 and S6), inspection is performed (step S7), and the manufacture of the color cathode ray tube is completed.

On the inner surface of the face plate of a color cathode ray tube, carbon stripes (also called black stripes) are formed at intervals of about 0.25 mm to improve the contrast of a displayed image. . The formation of the carbon stripe is performed in the above step S1 (preparation of phosphor screen).

FIG. 8 is a flowchart showing the steps in manufacturing a phosphor screen, and FIG. 9 is a sectional view showing a face plate of a color cathode ray tube for each step in FIG. As shown in FIG. 8, in the production of the phosphor screen, first, a carbon stripe is produced (step S11). Specifically, as a pre-process, a photosensitive coating film is formed by applying a PVA photosensitive solution or a PVP photosensitive solution to the inner surface of the face plate after cleaning, and a patcher grill, which is a lattice-shaped shadow mask, is placed inside the face plate. After that, the photosensitive coating film is irradiated with ultraviolet rays passing through the correction lens system from the mercury lamp through the aperture grill to expose the photosensitive coating film.

Next, after removing the aperture grill,
The unexposed portion of the photosensitive coating is removed, and a carbon film is uniformly formed on the whole. Subsequently, the photosensitive coating remaining in the stripe shape is decomposed by a predetermined chemical, and the carbon applied thereon is peeled off and removed. As a result, a carbon stripe 102 as shown in FIG. 9A is formed on the inner surface of the face plate.

Thereafter, as shown in FIG. 9B, red, green, and blue phosphors are applied to the gaps between the carbon stripes 102 to form red phosphor stripes 104R, green phosphor stripes 104G, and so on. Blue phosphor stripe 104B
Are formed (Step S12), and a primal liquid is applied thereon (Step S13), thereby forming a primal intermediate film 106 as shown in FIG. 9C. continue,
As shown in FIG. 9D, an aluminum vapor-deposited film 108 is formed on the primal intermediate film 106 as a metal back layer for increasing the luminous efficiency of the phosphor (step S1).
4) After that, the primal interlayer 1 with a predetermined agent
06 is decomposed and removed, and the aluminum vapor-deposited film 108 is
In close contact.

In the color cathode ray tube manufactured as described above, ideally, the entire surface of the tube should emit white light when an electron beam is uniformly incident on each phosphor from each electron gun. However, in actuality, a color is slightly colored in a specific region of the display screen due to various errors, and for example, a difference in chromaticity may occur between the center and the peripheral portion of the display screen. Such a difference in chromaticity is caused by a difference in the amount of light emission of each phosphor in the region, and therefore, by reducing the difference in the amount of light emission, this problem can be alleviated. .

The amount of light emission can be adjusted by changing the width of each of the phosphor stripes 104R, 104G, 104B. For example, when red is too strong, the width of the red phosphor may be reduced, and when green is weak, the width of the green phosphor may be increased. The width of the phosphor can be adjusted by changing the width of the carbon stripe 102, and the interval between the carbon stripes 102 can be changed by changing the amount of ultraviolet light applied to the photosensitive coating film.

Therefore, conventionally, in order to adjust the light emission amount,
The transmittance of the light amount correction filter provided for each color is individually changed for each filter to adjust the amount of ultraviolet light incident on the photosensitive coating film.

[0010]

However, in such an adjusting method, when the ultraviolet light transmittance of the light amount correction filter corresponding to the phosphor of a certain color is changed in order to adjust the light emission amount of the phosphor of a certain color, the light sensitivity is reduced. The amount of ultraviolet light incident on the entirety of the coating film will change. For this reason, even if the difference in chromaticity as described above can be eliminated to some extent, there is a side effect that the balance of the light emission amount is lost in a region where the adjustment of the light emission amount is not necessary. Therefore, a more reliable solution that can be applied to a color cathode ray tube requiring high performance has been desired.

The present invention has been made in view of such a point, and an object of the present invention is to provide a color cathode ray tube exposure method and apparatus capable of performing a balance adjustment of a light emission amount in a specific region on a tube surface. To provide.

[0012]

According to the present invention, in order to achieve the above object, when forming a carbon stripe on the inner surface of a face plate of a color cathode ray tube, a photosensitive layer formed on the inner surface of the face plate is used as a pre-process. In a method of exposing a coating film through a slit of an aperture grill, the photosensitive film is irradiated with the ultraviolet rays through a light amount correction filter having locally different transmittance of ultraviolet rays.

The present invention also provides an apparatus for exposing a photosensitive coating film formed on the inner surface of a face plate of a color cathode ray tube through a slit of an aperture grill as a pre-process before forming a carbon stripe on the inner surface of the face plate of the color cathode ray tube. , A light amount correction filter through which ultraviolet rays incident on the photosensitive coating film pass and locally having different transmittance of the ultraviolet rays is provided.

Therefore, according to the present invention, it is possible to adjust the light emission amount of each phosphor only in a specific region of the tube surface where the chromaticity needs to be adjusted. There is no side effect such as a loss of light emission balance in the non-existent region.

[0015]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Next, embodiments of the present invention will be described with reference to the drawings. FIG. 1 is a block diagram showing an example of a color cathode ray tube exposure apparatus according to the present invention, and FIG. 2 is a block diagram showing in detail a light source, a light amount correction filter, and a light source position correction lens which constitute the color cathode ray tube exposure apparatus of FIG. It is. In the following, the color cathode ray tube exposure apparatus of FIG. 1 will be described first, and then the color cathode ray tube exposure method of the present invention performed using the color cathode ray tube exposure apparatus will be described.

As shown in FIG. 1, an exposure apparatus 2 for a color cathode ray tube according to the present embodiment comprises an exposure table main body 4, an ultraviolet light source 6,
It is configured to include a shutter 8, a light amount correction filter 10, a light source position correction lens 12, an electron beam trajectory correction lens 14, and the like. The light source 6 composed of a mercury lamp is disposed at a lower portion in the exposure table main body 4 with an ultraviolet ray emission part facing upward. As shown in FIG. 2, the light source 6 includes three ultraviolet light sources 6R, 6G, and 6B corresponding to phosphors of three colors, red, green, and blue. Each light source 6R,
6G and 6B are arranged in the color cathode ray tube at the positions of the deflection centers of the electron beams incident on the phosphors of the three colors red, green and blue, respectively.

Above the light source 6, a shutter 8 is interposed.
In particular, a light amount correction filter 10 according to the present invention is provided. As shown in FIG. 2, the light amount correction filter 10
Light amount correction filter 10R, light amount correction filter 10G, light amount correction filter 1 corresponding to phosphors of three colors of red, green, and blue
OB are provided side by side.

The light source position correcting lens 12 is disposed above such a light amount correcting filter 10, and as shown in FIG. 2, a light source position correcting lens corresponding to three color phosphors of red, green and blue. 12R, a light source position correcting lens 12G, and a light source position correcting lens 12B.

The electron beam trajectory correction lens 14 is disposed above the light source position correction lens 12 at a distance from the light source position correction lens 12. The face plate 16 forming the surface of the color cathode ray tube is
, With its inner surface facing downward. After cleaning, the inner surface of the face plate 16 is coated with a PVA photosensitive solution or a PVP photosensitive solution to form a photosensitive coating 1.
An aperture grille 20 is set at an interval (downward in the figure).

When the color cathode ray tube exposure apparatus 2 of this embodiment is used, the manufacturing process of the color cathode ray tube is basically the same as the conventional manufacturing process, and therefore, is performed according to the flowchart shown in FIG. Will be. The first step, that is, the preparation of the phosphor screen, is also performed according to the flowchart shown in FIG. Then, the exposure apparatus 2 for a color cathode ray tube according to the present embodiment is used for producing a carbon stripe in step S11 in FIG.

As shown in FIG. 1, the face plate 16
When the shutter 8 is opened in a state where the
The ultraviolet rays that have exited R, 6G, and 6B enter the light quantity correction filters 10R, 10G, and 10B, respectively, and are adjusted to appropriate light quantities by passing through these filters. Thereafter, each ultraviolet ray is applied to the light source position correcting lens 12R,
12G and 12B, the displacement of each of the light sources 6R, 6G and 6B due to the positional shift and the like is corrected in these lenses, and the ultraviolet rays are incident on the face plate 16 at an appropriate position and direction.

Light source position correcting lenses 12R, 12G, 12
The ultraviolet light passing through B is corrected by the electron beam trajectory correction lens 14 so as to be incident on the inner surface of the face plate 16 in the same optical path as the actual electron beam.
The light enters the photosensitive coating film 18 through the aperture grill 20.

As a result of the exposure of the photosensitive coating film 18 through the aperture grill 20, the photosensitive coating film 18 is exposed in a stripe shape. After the aperture grill 20 is removed, an unexposed portion of the photosensitive coating film 18 is exposed. Is removed, the photosensitive coating film 18 remains on the inner surface of the face plate 16 in a stripe shape. Therefore, when a carbon film is uniformly formed on the entire surface, the photosensitive coating film 18 remaining in a stripe shape is decomposed by a predetermined chemical, and the carbon applied on the photosensitive coating film 18 is removed and removed. The carbon stripe 102 as shown in FIG. 9A is formed on the inner surface of the plate. After that, FIG.
Steps S12 and subsequent steps are sequentially performed to complete the phosphor screen manufacturing step, and further, the remaining steps in FIG. 7 are sequentially performed to complete the manufacture of the color cathode ray tube.

In the color cathode ray tube manufactured as described above, when an electron beam is uniformly incident on each phosphor from each electron gun, ideally the entire tube surface should emit white light. However, in practice, as described above, there is a case where a difference occurs in the light emission amount of each phosphor due to various errors, and a specific area of the tube surface is slightly colored. FIG. 3 is an explanatory diagram showing a case where a specific region of the tube surface 22 is colored due to such a local difference in light emission amount of the phosphor. For example, if the red and blue phosphors emit more light than green, the area M becomes magenta.

In this embodiment, in order to eliminate such a colored portion, the transmittance of the light amount correction filter 10 is locally adjusted according to the present invention. Hereinafter, this will be described. FIG. 4 is a plan view showing a state where the face plate 16 is viewed from the inside, and FIG. 5 is a sectional view of the face plate 16.

The light emission amount of each phosphor can be adjusted by changing the width of each phosphor stripe. Therefore, when the area M is magenta, the width W corresponding to the width of one dot on the screen is kept constant in FIGS.
Width W _R of 04B, a W _B may be narrower than the width W _G of the phosphor stripes 104G. To do so, the transmittance of the light amount correction filters 10R, 10G, and 10B for each color may be changed for each filter, and the amount of ultraviolet light applied to the photosensitive coating film 18 may be changed.

By the way, there is a one-to-one correspondence between an ultraviolet ray passing point in the light amount correction filter 10 and a point on the face plate 16 where the ultraviolet ray passing through that point is incident. FIG. 6 is an explanatory diagram showing the relationship between the ultraviolet ray passing point in the light amount correction filter 10 and the ultraviolet ray incident point in the face plate 16. As is apparent from FIG. 6, for example, each light beam L of the ultraviolet light emitted from the light source 6R passes through the light amount correction filter 10R and is applied to the face plate 16R.
Of the light amount correction filter 10R
When the light beam L passes through a specific portion of the face plate 16, the light beam L enters a corresponding specific portion of the face plate 16.

Therefore, as shown in FIG. 6, when the same two-dimensional orthogonal coordinates are set on the light amount correction filter 10R and the face plate 16, the light source 6R is emitted and the light amount correction filter One quadrant A1
All the light beams L passing through the first
The light enters the quadrant A1. The same applies to the ultraviolet rays that exit the light sources 6G and 6B and pass through the light amount correction filters 10G and 10B.

Therefore, in order to eliminate the magenta in the area M shown in FIG. 3, it is sufficient to adjust the amount of transmitted ultraviolet light in the areas on the light quantity correction filters 10R and 10B corresponding to this area of the face plate 16. In particular,
In this area M, the chromaticity may be adjusted to slightly increase. Therefore, in order to actually increase the chromaticity Y by +1, the light amount correction filter 10R in which the transmittance of ultraviolet rays in this area is reduced by 1.3%, and the transmittance of ultraviolet rays in this area is reduced by 0.7.
The light amount correction filters 10B with a% reduction were manufactured, and ultraviolet light exposure was performed using these light amount correction filters 10. As a result, as shown in the following table, the difference between the chromaticity at the center of the tube surface 22 and the chromaticity in the region M can be increased by about 1.5, and the chromaticity difference can be reduced. .

[0030]

[Table 1] In the present embodiment, since the transmittance is changed only in a portion corresponding to the region M, the chromaticity does not change in a portion other than the region M. Therefore, unlike the related art, there is no side effect that the light emission amount is lost in a region where the light emission amount does not need to be adjusted.

[0031]

As described above, according to the present invention, when a carbon stripe is formed on the inner surface of a face plate of a color cathode ray tube, a photosensitive coating formed on the inner surface of the face plate is used as a pre-process before the aperture grill. In the method of exposing through the slit, the ultraviolet rays are applied to the photosensitive coating film through a light amount correction filter having locally different transmittance of the ultraviolet rays.

According to the present invention, there is provided an apparatus for exposing a photosensitive coating film formed on an inner surface of the face plate through a slit of an aperture grill, as a pre-process before forming a carbon stripe on the inner surface of the face plate of the color cathode ray tube. In the above, a configuration is provided in which an ultraviolet ray incident on the photosensitive coating film passes, and a light amount correction filter having locally different transmittance of the ultraviolet ray.

Therefore, according to the present invention, it is possible to adjust the light emission amount of each phosphor only in a specific area of the tube surface where the chromaticity needs to be adjusted. There is no side effect such as a loss of light emission balance in the non-existent region.

[Brief description of the drawings]

FIG. 1 is a configuration diagram showing an example of an exposure apparatus for a color cathode ray tube according to the present invention.

FIG. 2 is a configuration diagram showing in detail a light source, a light amount correction filter, and a light source position correction lens included in the color cathode ray tube exposure apparatus of FIG.

FIG. 3 is an explanatory diagram showing a case where a specific region of a tube surface is colored by a difference in a local light emission amount of a phosphor.

FIG. 4 is a plan view showing a state where the face plate is viewed from the inside.

FIG. 5 is a sectional view of a face plate.

FIG. 6 shows an ultraviolet ray passage portion in the light amount correction filter,
It is explanatory drawing which shows the relationship with the incident part of ultraviolet rays in a face plate.

FIG. 7 is a flowchart showing a process of manufacturing a color cathode ray tube.

FIG. 8 is a flowchart showing each step in manufacturing a phosphor screen.

9 is a sectional view showing a face plate of the color cathode ray tube in each step of FIG.

[Explanation of symbols]

2 ... Exposure device for color cathode ray tube, 4 ... Exposure table body,
6, 6B, 6G, 6R: light source, 8: shutter, 1
0, 10B, 10G, 10R ... light amount correction filter, 1
2,12B, 12G, 12R ... light source position correcting lens,
14: electron beam locus correction lens, 16: face plate, 18: photosensitive coating, 20: aperture grille, 22: tube surface, 102: carbon stripe,
104B, 104G, 104R ... phosphor stripes,
106: Primal intermediate film, 108: Aluminum vapor-deposited film.

Claims (8)

[Claims] 1. A method of exposing a photosensitive coating film formed on an inner surface of a face plate through a slit of an aperture grill, as a pre-process, before forming a carbon stripe on an inner surface of a face plate of a color cathode ray tube. Irradiating the photosensitive coating film with the ultraviolet light through a light amount correction filter having a different transmittance of the ultraviolet light. 2. The color cathode ray tube exposure method according to claim 1, wherein different light amount correction filters are used for each of the phosphors that emit red, green, and blue light. 3. The exposure method for a color cathode ray tube according to claim 1, wherein the ultraviolet light source, which differs for each of phosphors emitting red, green and blue light, is used. 4. The ultraviolet light emitted from the light source passes through a shutter, the light amount correction filter, the light source position correction lens, and the electron beam trajectory correction lens in this order, and is incident on the photosensitive coating film. An exposure method for a color cathode ray tube according to claim 1. 5. An apparatus for exposing a photosensitive coating film formed on an inner surface of a face plate through a slit of an aperture grill as a pre-process before forming a carbon stripe on an inner surface of a face plate of a color cathode ray tube, An exposure apparatus for a color cathode ray tube, comprising: a light amount correction filter through which ultraviolet light incident on a photosensitive coating film passes and having a locally different transmittance of the ultraviolet light. 6. An exposure apparatus for a color cathode ray tube according to claim 5, further comprising a different light amount correction filter for each of the phosphors emitting red, green, and blue light. 7. The exposure apparatus for a color cathode ray tube according to claim 5, further comprising a light source for the ultraviolet light, which is different for each of phosphors emitting red, green, and blue light. 8. The ultraviolet light emitted from the light source passes through the shutter, the light amount correction filter, the light source position correction lens, and the electron beam trajectory correction lens in this order, and enters the photosensitive coating film. An exposure apparatus for a color cathode ray tube according to claim 5.