JP2001006544A - Exposure device used to manufacture color cathode ray tube - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an exposure device for a phosphor surface capable of outputting a continuous picture having good quality and no dislocation in regard to the boundaries of plural divided areas, to be applied to a split-scan color cathode ray tube. SOLUTION: This exposure device 50 to form a phosphor surface on the inner surface of the panel 12 of a half-split type color cathode ray tube equipped with two electron guns has light sources 52a, 52b to divide a light sensitive material applied to the inner surface of the panel into two divided areas and expose each of them. Landing compensation lenses 54a, 54b to compensate landing against the inner surface of the panel by compensating the orbit of an ultraviolet ray are disposed on the optical axis of each light source. Each compensation lens has an asymmetrical shape having a smaller thickness as it goes toward the center of the panel with respect to each optical axis, and also has asymmetrical characteristics with respect to the optical axis.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an exposure apparatus for forming a fluorescent screen on an inner surface of a panel of a color cathode ray tube, and more particularly, to scanning by dividing the fluorescent screen into a plurality of divided areas.
The present invention relates to an exposure apparatus used for manufacturing a color cathode-ray tube of a division scanning method for combining color images drawn in respective divided regions and displaying the combined image as one color image.

[0002]

2. Description of the Related Art In general, a large drawback of a color cathode ray tube is that it has a large depth. In recent years, color cathode ray tubes have been increasing in size, and in particular, improvement of this drawback has been strongly demanded.

[0003] As a technique capable of shortening the depth, an idea of a division scanning method has been conventionally proposed. This is an idea that a single phosphor screen is divided into a plurality of divided regions by using a plurality of electron guns and deflection yokes and scanned, and images of the respective regions are joined to form a large screen.

[0004] Further, according to this technique, it is possible to increase the resolution as compared with a normal color cathode ray tube.

A color cathode ray tube of this kind is a vacuum comprising a panel, a rear envelope connected to the panel and having, for example, two funnels, and two necks connected to each funnel. It has an envelope. A deflection device is mounted outside each funnel, and an electron gun is provided inside each neck.

In the color cathode ray tube having the above structure, the electron beams emitted from the respective electron guns are deflected by the magnetic field generated by the corresponding deflecting device, and the two fluorescent screens integrally formed on the inner surface of the panel are correspondingly formed. And scans. The images drawn on the phosphor screen by the divided scanning are connected by controlling signals applied to the electron gun and the deflecting device, thereby reproducing one image having no break or overlap on the entire phosphor screen.

In general, when a phosphor screen is formed on the inner surface of a panel of a color cathode ray tube, a phosphor slurry using a sensitized photosensitive resin is applied to the inner surface of the panel, and the coating film is exposed to light through a shadow mask. After developing the resin, it is developed. Further, in order to improve contrast, a black material layer is usually formed between the inner surface of the panel and the phosphor screen in the same manner as the phosphor screen.

An exposure apparatus for forming a fluorescent screen on the inner surface of a panel has a light source for emitting ultraviolet light for exposure, and a landing correction lens for correcting the trajectory of ultraviolet light emitted from the light source. I have. Landing correction lens
The trajectory of the ultraviolet light is designed to correspond to the trajectory of the electron beam when assembled as a cathode ray tube.

By the way, in order to operate the above-mentioned color cathode ray tube, it is necessary to seal the panel on which the fluorescent screen is formed to the rear envelope, and then exhaust the gas in the tube to make a vacuum state. When the inside of the tube is evacuated, the panel is deformed into a concave shape by the atmospheric pressure, and the landing changes.

In the case of a cathode ray tube having a single electron gun, since the center of the panel is on the tube axis of the funnel, there is almost no landing change of the whole panel caused by the concave deformation of the panel. However, in the above-mentioned color cathode ray tube of the split scanning method, since the deflection angle is maximized at the center of the panel where the amount of change of the panel concave deformation is maximum, the landing change of the entire panel caused by the panel concave deformation is extremely large, and It cannot be used as a cathode ray tube.

[0011]

Therefore, when a correction lens of an exposure apparatus such as that used in the manufacture of a conventional cathode ray tube having a single electron gun is used for a color cathode ray tube of a divided scanning system, the boundary of each divided region is not increased. In some parts, the landing deviation becomes remarkably large.

SUMMARY OF THE INVENTION The present invention has been made in view of the above points, and has as its object the application of the present invention to a color scanning cathode-ray tube of a division scanning method to produce a continuous high-quality image without landing deviation on the boundaries of a plurality of division regions. An object of the present invention is to provide a fluorescent screen exposure apparatus capable of outputting.

[0013]

In order to achieve the above object, according to the exposure apparatus of the present invention, a phosphor screen is divided into a plurality of divided areas and scanned, and a plurality of color images drawn in each divided area are scanned. An exposure apparatus used for manufacturing a color cathode ray tube of a split scanning system for combining and displaying as one color image, wherein a photosensitive material applied to an inner surface of a panel of a vacuum envelope of the color cathode ray tube is exposed. In the exposure apparatus for forming the fluorescent screen, a panel holding a shadow mask having a large number of electron beam passage holes facing the inner surface coated with the photosensitive material is held at a predetermined exposure position. A member is provided in correspondence with the plurality of divided areas, and the exposure light is directed toward the inner surface of the panel held at a predetermined exposure position, and a large number of electron beams pass through the shadow mask. Through the holes, a plurality of light sources that divide the photosensitive material applied to the inner surface into the plurality of divided areas and respectively expose the light, between each light source and the shadow mask corresponding to the plurality of light sources. And a plurality of correction means for respectively correcting the trajectories of the exposure light so as to correct the landing, wherein at least two of the plurality of correction means are provided with respect to the optical axis of the corresponding light source. Has a landing correction characteristic that is asymmetric in the direction in which the divided regions are arranged.

According to this exposure apparatus, at least two correction means having asymmetrical landing correction characteristics in the direction in which the plurality of divided areas are arranged with respect to the optical axes of at least two of the plurality of light sources for exposure are provided. ing. For this reason, when the panel is assembled as a vacuum envelope, even if it is deformed by the influence of atmospheric pressure, it forms a phosphor screen that can output a continuous high-quality image without a landing gap near the boundary between a plurality of divided areas. it can. A color cathode ray tube having a phosphor screen formed by using this exposure apparatus can output a continuous high-quality image with no deviation between a plurality of divided areas that are divided and scanned.

According to the above-described exposure apparatus of the present invention, the at least two correction units each include a correction lens having a correction characteristic that is asymmetric with respect to the optical axis of the corresponding light source in the direction in which the plurality of divided regions are arranged. Including
Each correction lens has an asymmetric cross-sectional shape thinned in the central axis direction of the panel.

According to the above-described exposure apparatus of the present invention, the first correcting means of the plurality of correcting means is disposed at a position shifted from the central axis of the panel in the direction in which the plurality of divided areas are arranged. Has a landing correction characteristic that is asymmetric in the arrangement direction with respect to the optical axis of the corresponding light source,
The second correction means disposed at a position facing the central axis of the panel among the plurality of correction means has a landing correction characteristic symmetric in the arrangement direction with respect to the optical axis of the corresponding light source. Features.

According to the above-described exposure apparatus of the present invention, the first correction means has the first correction lens having a cross-sectional shape that is asymmetrical in the arrangement direction with respect to its optical axis, and the second correction means The means has a second correction lens having a cross-sectional shape symmetrical with respect to the optical axis in the arrangement direction.

Further, according to the exposure apparatus of the present invention, the phosphor screen is divided into a plurality of divided regions and scanned, and a plurality of color images drawn in each divided region are combined and displayed as one color image. An exposure apparatus used for manufacturing a scanning type color cathode ray tube, comprising: exposing a photosensitive material applied on an inner surface of a panel of a vacuum envelope of the color cathode ray tube to form the phosphor screen. In the apparatus, a holding member for holding a panel mounted with a shadow mask having a large number of electron beam passage holes facing the inner surface coated with the photosensitive material at a predetermined exposure position, and a plurality of divided regions corresponding to the plurality of divided regions. Provided, and irradiate exposure light toward the inner surface of the panel held at a predetermined exposure position, and applied to the inner surface through a number of electron beam passage holes of the shadow mask. A plurality of light sources that divide the light-sensitive material into the plurality of divided regions and respectively expose the light source, and are provided between each light source and the shadow mask corresponding to the plurality of light sources, respectively, for exposure to correct landing. A plurality of correction means for correcting the trajectories of light, respectively, wherein the plurality of correction means form a fluorescent screen on the inner surface of the panel, and then the panel is assembled as the vacuum envelope and the atmospheric pressure is adjusted. When it is deformed by (1), it has an asymmetrical landing correction characteristic for correcting a change in landing caused by this deformation.

Further, according to the exposure apparatus of the present invention described above, each of the correction means includes a correction lens having a correction characteristic that is asymmetric with respect to an optical axis of each of the plurality of light sources in a direction in which the plurality of divided areas are arranged. Each of the correction lenses has an asymmetric cross-sectional shape that is thinned in the central axis direction of the panel.

[0020]

Embodiments of the present invention will be described below in detail with reference to the drawings.

According to the present invention, there is provided a color scanning cathode ray tube of a division scanning system which divides one fluorescent screen into a plurality of divided regions, scans the divided regions, combines color images drawn in the respective divided regions, and displays the combined image as one color image. The present invention relates to an exposure apparatus used in the manufacture of a device. Before describing the exposure apparatus of the present invention,
With regard to the color cathode ray tube of the division scanning system to which the present invention is applied, in particular, the two cathode ray tubes drawn by separately scanning two divided regions are used.
A two-segment color cathode ray tube that combines two color images and displays the combined image as one color image will be described with reference to FIGS. 1 to 3.

As shown in FIG. 1, a two-part color cathode ray tube 1 has a vacuum envelope 10 in which two cathode ray tubes are arranged side by side. The vacuum envelope 10 includes a substantially rectangular panel 12 made of glass, and two funnels 16 provided opposite to the panel 12.
And a rear enclosure 14 made of glass in which are integrally arranged side by side.

As shown in detail in FIG. 2 and FIG. 3, the panel 12 has a substantially rectangular face plate 18 having a rectangular fluorescent screen 15 formed on the inner surface thereof, and an upright edge on the periphery of the face plate 18. And the provided skirt portion 20. The panel 12 has a major axis (horizontal axis) X and a minor axis (vertical axis) Y extending in the directions orthogonal to each other through the center (panel center).
In the following description, the major axis X direction may be referred to as a horizontal direction, and the minor axis direction may be referred to as a vertical direction.

The phosphor screen 15 formed on the inner surface of the panel 12
Is a stripe-shaped three-color phosphor layer extending in the short-axis Y direction and emitting blue, edge, and red light;
And black stripes provided between the color phosphor layers. The fluorescent screen 15 is integrated in the entire screen area and is formed continuously without any joint.

The rear envelope 14 is joined to the panel 12 by, for example, frit glass in a state where the rear envelope 14 is in contact with the end surface of the skirt portion 20 of the panel 12.

At the small diameter ends of the funnels 16 arranged on the left and right sides of the rear envelope 14, necks 22 made of glass and extending in parallel with each other are joined. Each neck 22
Inside, an electron gun assembly 24 for emitting an electron beam toward the phosphor screen 15 is arranged. Outside each funnel 16, a deflection device 28 for deflecting the electron beam emitted from the electron gun assembly 24 is mounted.

Inside the vacuum envelope 10, there is provided a substantially rectangular shadow mask structure 30 in which a large number of electron beam passage holes are formed. This shadow mask structure 30
Are provided at a position facing the fluorescent screen 15 and are fixed to a mask frame 38, which will be described later, and stud pins 34 protruding from the skirt portion 20 of the panel 12.
, And is suspended from the panel 12.

As can be seen from FIGS. 2 and 3, the phosphor screen 15 has two divided areas A and B arranged in the long axis X direction, that is, on the left and right sides, with the short axis Y of the panel 12 as the boundary C. I have. These divided areas A and B have the same rectangular shape. The two necks 22 and the electron gun assembly 24 are arranged such that their center axes D coincide with a normal passing substantially through the centers of the corresponding divided areas A and B.

The shadow mask structure 30 includes a substantially rectangular shadow mask 36 having a skirt at the periphery and a substantially rectangular mask frame 38 attached to the periphery of the shadow mask 36. The shadow mask 36 has rectangular effective areas a and b respectively corresponding to the divided areas A and B of the phosphor screen 15 and a non-porous portion 40 located around each effective area. A large number of electron beam passage holes 42 are formed in the effective areas a and b, respectively. In the non-porous portion 40, a boundary region 41 located between the effective regions a and b extends so as to face the boundary C of the fluorescent screen 15.

According to the color cathode ray tube of the two-division type having the above structure, the electron beams emitted from the two electron gun assemblies 24 are deflected by the magnetic fields generated by the corresponding deflecting devices 28, and the shadow mask assembly 30 is effectively used. The two divided areas A and B of the phosphor screen 15 are horizontally and vertically scanned through the areas a and b, respectively. This divisional scanning allows the fluorescent screen 15
The color images drawn on each of the divided areas A and B are separate from each other, but are connected at the boundary C by controlling signals applied to the electron gun assembly 24 and the deflecting device 28, and the entire surface of the fluorescent screen 15 is Play one large, continuous color image.

The above-described two-part color cathode ray tube is
Manufacturing and assembly are performed by the following steps.

First, the phosphor screen 15 is formed on the inner surface of the face plate 18 of the panel 12 before the rear envelope 14 is joined.

When the fluorescent screen 15 is to be formed, a photosensitive material is applied to the inner surface of the face plate 18 of the panel 12 with the shadow mask structure 30 removed from the panel 12, and then the photosensitive material is applied via the holder 32 and the stud pins 34. Then, the shadow mask structure 30 is mounted on the panel 12.

Then, the panel 12 on which the shadow mask structure 30 is mounted in this manner is set in an exposure apparatus of the present invention described later, and two light sources of the exposure apparatus described later are connected to the face plate 18 via the shadow mask structure 30. Is irradiated with ultraviolet light for exposure to expose the photosensitive material applied to the inner surface of the panel. At this time, each divided area A, B
Ultraviolet light is emitted from each corresponding light source, and the photosensitive material applied to the inner surface of the panel is exposed for each of the divided areas A and B.

After the exposure, the shadow mask structure 30 is removed again, and the exposed photosensitive material is etched.
Remove unnecessary parts.

The above steps are performed for each of the red, blue and green fluorescent materials.

Usually, a black material layer called a black stripe is formed between the phosphors. In this case, prior to the above steps, using a photosensitive resist,
A black stripe is formed using a similar exposure apparatus. After the formation of the phosphor, a filter layer may be formed in order to improve contrast and brightness. In this case, a similar exposure apparatus is used.

Subsequently, the shadow mask structure 30 is mounted on the panel 12 on which the fluorescent screen 15 is formed as described above,
The rear envelope 14 is joined and sealed to the skirt portion 20 of the panel 12, and the electron gun assembly 24 is sealed in each neck 22. Further, after the gas in the tube is evacuated and evacuated, a deflector 28 is attached to the outer periphery of each funnel 16 to assemble a two-part color cathode ray tube.

By the way, in the manufacturing process of the above-described two-segment type color cathode ray tube, after the panel 12 on which the fluorescent screen 15 is formed is sealed to the rear envelope 14, the inside of the tube is evacuated and assembled as a vacuum envelope. It is known that the face plate 18 of the panel 12 is deformed into a concave shape under the influence of atmospheric pressure.

Further, as described above, when the fluorescent screen 15 is formed on the inner surface of the panel 12, there is no influence by the atmospheric pressure caused by the negative pressure inside the vacuum envelope. The phosphor screen 15 is formed on the substrate.

That is, landing deviation occurs because the arrival point of the ultraviolet light for exposure at the time of exposing the phosphor screen is different from the arrival point of the electron beam at the time of outputting a color image.

Usually, in order to correct the landing, the exposure apparatus is provided with a correction lens for correcting the trajectory of the ultraviolet light emitted from the light source. In an exposure apparatus used for manufacturing a conventional cathode ray tube having a single electron gun,
Since the panel center and the optical axis of the correction lens match,
The correction lens has a symmetrical cross-sectional shape having a correction characteristic symmetrical with respect to the optical axis of the ultraviolet light.

However, in the color cathode ray tube of the two-division system as described above, since the face plate 18 of the panel 12 is recessed around the center of the panel, the optical axis of each of the electron beams emitted from the two electron gun assemblies 24. In contrast, the panel 12 is deformed left and right asymmetrically.
For this reason, the fluorescent screen 15 of the above-described two-segment type color cathode ray tube is formed by using two correction lenses whose correction characteristics are symmetric with respect to the optical axis as in the conventional exposure apparatus described above. When the exposure is performed, when a color image is output through the phosphor screen 15, a large landing shift occurs in an image near the boundary C along the short axis of the panel 12.

FIG. 4 shows a panel 1 having a screen diagonal diameter of 86 cm.
2 illustrates the amount of deformation in the Z direction (tube axis direction) attributable to the atmospheric pressure in each part of the face plate 18 of the panel 12 when assembling 2 as the vacuum envelope 10. According to this, it can be seen that the amount of deformation of the face plate 18 in the Z direction increases as approaching the panel center, with the maximum (panel center) deformation amounting to 260 μm.

FIG. 5 shows the amount of change in landing of the electron beam in each part of the face plate 18 due to the deformation of the face plate 18 described with reference to FIG. According to this, at substantially the center of the divided region A through which the optical axis of one of the electron beams (the left side in the figure) passes, the amount of change in landing of the electron beam is zero before and after the deformation, and The amount of change increases from the center to the periphery.
It can be seen that it is also m. In addition, in such a two-part color cathode ray tube, it can be seen that the amount of change in landing of the electron beam due to deformation of the panel 12 due to atmospheric pressure is not symmetrical with respect to the optical axis of each electron beam.

Accordingly, in the present embodiment, the trajectory of the ultraviolet light at the time of exposure is corrected in order to correct a left-right asymmetric change with respect to the optical axis of the landing of the electron beam due to the deformation of the face plate 18 due to the influence of the atmospheric pressure. Is corrected to be left-right asymmetric with respect to the optical axis.

FIG. 6 is a sectional view showing a schematic configuration of an exposure apparatus 50 according to an embodiment of the present invention. FIG. 7 is a diagram for explaining correction characteristics of a later-described landing correction lens incorporated in the exposure apparatus 50.

The exposure apparatus 50 houses an optical system for transmitting ultraviolet light for exposure, and has a frame 51 for mounting the panel 12 on which a photosensitive material is applied and on which the shadow mask structure 30 is mounted. are doing. Frame 51
An upper end surface 51a for supporting the panel 12 in a state in which the end of the skirt portion 20 of the panel 12 is in contact with the upper end of the panel 12 is formed.

Inside the frame 51, light sources 52a, 52b for irradiating ultraviolet light toward the panel 12 positioned and mounted on the upper end surface 51a of the frame 51 are provided.
Σ lenses 53a and 53b for correcting the side beam landing, landing correction lenses 54a and 54b for correcting the trajectory of each ultraviolet light to correct the landing of the ultraviolet light on the inner surface of the panel, and a terrestrial magnetism correction lens 5.
5a, 55b and light quantity distribution correction filters 56a, 5b
6b are sequentially arranged at predetermined intervals. These optical systems are positioned and arranged at predetermined positions in the frame 51 by positioning means (not shown).

Light sources 52a and 52b, σ lenses 53a and 5
3b, the terrestrial magnetism correction lenses 55a and 55b, and the light amount distribution correction filters 56a and 56b are arranged such that their optical axes coincide with a normal passing substantially through the center of the corresponding divided area A or B of the fluorescent screen 15. ing.

Landing correction lenses 54a, 54b
Correspond to the corresponding light source 52a, as shown in the schematic diagram of FIG.
Each has a shape that is asymmetrical with respect to the optical axis of (52b). That is, the landing correction lens 54a provided corresponding to the light source 52a on the left side in the figure is formed in a shape that becomes thinner toward the panel center, that is, toward the + X side, and corresponds to the light source 52b on the right side in the figure. The provided landing correction lens 54b is formed in a shape that becomes thinner toward the panel center, that is, toward the −X side. In other words, each landing correction lens 54a, 54b is
The correction characteristics are asymmetrical with respect to the optical axes a and 52b. Further, the two landing correction lenses 54a and 54b have correction characteristics that are symmetrical with respect to the panel center of the face panel 12 as a whole.

By using the landing correction lenses 54a and 54b having the asymmetric correction characteristics as described above, the trajectory of the ultraviolet light with respect to the inner surface of the panel 12 which is not deformed by the atmospheric pressure is corrected to the normal state shown by the solid line in FIG. it can. In FIG. 7, the trajectory of the electron beam in consideration of the deformation of the panel 12 is shown by a broken line for comparison.

As described above, the landing correction lenses 54a and 54b for correcting the landing of the ultraviolet light in the optical system of the exposure apparatus 50 have a shape that is asymmetrical with respect to the optical axis thereof, so that the correction characteristics of the ultraviolet light can be improved. Can be made asymmetrical, and a landing deviation that is asymmetrical with respect to the optical axis of the electron beam due to the deformation of the face panel 12 can be corrected. That is, the exposure apparatus 5 of the present invention
When 0 is used, a two-part color cathode ray tube capable of displaying a continuous high-quality color image without a landing deviation near the panel center can be manufactured.

Next, an exposure apparatus 60 according to another embodiment of the present invention will be described with reference to FIG. The exposure device 60 scans a single phosphor screen by dividing it into three divided areas A, B, and C in the left-right direction, and combines the color images drawn in each divided area to display one color image. It is used for producing a three-part color cathode ray tube.

The exposure apparatus 60 accommodates a plurality of optical systems for transmitting ultraviolet light for exposure, and a panel 1 on which a photosensitive material is applied and a shadow mask structure 30 is mounted.
It has a frame 61 on which 2 ′ is placed. At the upper end of the frame 61, an upper end surface 6 supporting the panel 12 'in a state where the end of the skirt portion 20 of the panel 12' is in contact with the upper end surface.
1a is formed.

Inside the frame 61, the panel 12 'positioned and mounted on the upper end surface 61a of the frame 61 is mounted.
Light sources 62a and 62 for irradiating ultraviolet light toward
b, 62c, σ lenses 63a, 63b, 63c for correcting the side beam landing, and landing correction lenses 64a, 64 for correcting the trajectory of each ultraviolet light and correcting the landing of the ultraviolet light on the inner surface of the panel.
b, 64c, geomagnetic correction lenses 65a, 65b, 65
c, and light amount distribution correction filters 66a, 66b, 66
c are sequentially arranged at predetermined intervals.
These three optical systems are arranged at predetermined positions in the frame 61 by positioning means (not shown).

Light sources 62a, 62b, 62c, σ lens 6
3a, 63b, 63c, geomagnetic correction lenses 65a, 65
b, 65c and light amount distribution correction filters 66a, 66
The reference numerals b and 66c are arranged such that their optical axes coincide with a normal passing substantially through the center of the corresponding divided areas A, B and C (not shown) of the fluorescent screen 15.

Two of the three light sources 62a, 62b and 62c are provided corresponding to the light sources 62a and 62c on both sides which are arranged at positions symmetrical with respect to the panel center C.
The two landing correction lenses 64a, 64c have shapes that are asymmetrical with respect to the optical axis of each of the corresponding light sources 62a, 62c. That is, the light source 62 on the left side in FIG.
Landing correction lens 64a provided corresponding to a
Is closer to the panel center C, that is, + X
The light source 6 on the right side in FIG.
Landing correction lens 64 provided corresponding to 2c
c approaches the panel center, that is, −X
It is formed in a shape that becomes thinner toward the side. In other words, the two landing correction lenses 64a and 64c
The light sources 62a and 62c have correction characteristics that are asymmetrical with respect to the optical axis of each of the light sources 62a and 62c.

On the other hand, the center landing correction lens 64b provided corresponding to the center light source 62b provided corresponding to the panel center C has a symmetrical shape with respect to the optical axis, that is, a symmetrical correction characteristic. have. That is, since the face panel 12 'is depressed around the panel center due to the influence of the atmospheric pressure, the central landing correction lens 64b disposed at the panel center has symmetrical correction characteristics.

As described above, in the exposure apparatus 60 having three exposure optical systems, the landing correction lens 64b of the central optical system is formed to be symmetrical with respect to the optical axis, and the landing correction lenses 64a and 64c on both the left and right sides. The panel 1 has a shape that is asymmetrical with respect to the optical axis.
The landing deviation of the electron beam accompanying the deformation of 2 ′ can be corrected. That is, by using the exposure apparatus 60 of the present invention, it is possible to manufacture a color cathode ray tube capable of displaying a continuous high-quality color image without any landing deviation near the boundary between the divided areas A, B, and C on the phosphor screen.

As described above, a two-division system having a screen composed of a large number of stripe-shaped three-color phosphor layers extending in the short-axis Y direction and black stripes provided between these three-color phosphor layers ( Hereinafter, the color cathode ray tube of the two-division scanning vertical stripe system has been described. Next, the two-division system (hereinafter, the two-division scanning horizontal stripe system) having a screen constituted by stripes extending in the major axis X direction has been described. The color cathode ray tube will be described.

The color cathode ray tube of the two-division scanning horizontal stripe type has a configuration as shown in FIGS. 1 to 3 like the color cathode-ray tube of the two-division scanning vertical stripe type. The screen formed on the inner surface of the panel extends in the long axis X direction and is composed of a large number of striped three-color phosphor layers and black stripes provided between these three-color phosphor layers. The screen is integrated in the entire screen area and is formed continuously without any seams.

Even in the case of the two-division scanning horizontal stripe system, when forming a screen on the inner surface of the panel,
Since there is no influence by the atmospheric pressure, a screen is formed on the inner surface of the panel before the deformation. That is, at the time of exposure of the screen, the ultraviolet light for exposure reaches the inner surface of the panel, and the electron beam reaches the inner surface of the panel,
Are different.

When a panel having a screen diagonal diameter of 86 cm is assembled as the vacuum envelope 10, the deformation distribution in the Z direction (tube axis direction) due to the atmospheric pressure at each part of the face surface 18 is divided into two scans. As in the case of the vertical stripe method, FIG.
become that way. The landing changes depending on the amount of deformation of the face surface 18 in the Z direction, and this change direction is a direction orthogonal to the stripe direction. For this reason, the landing change direction is the X direction in the two-division scanning vertical stripe method, but is different from the Y direction in the two-division scanning horizontal stripe method. The change in landing is shown in FIG. 10 corresponding to FIG. The maximum landing change amount is 80 μm, which is smaller than that of the vertical stripe method, but is very large in forming a screen. The landing change amount distribution is different from the two-division scanning vertical stripe method in that the landing movement amount is zero on the X axis and is not asymmetric, but the distribution is still asymmetric as a whole. Therefore, similarly to the case of the two-division scanning vertical stripe method, it is necessary to correct the trajectory of the ultraviolet light at the time of exposure so as to be left-right asymmetric with respect to the optical axis.

The shape of the correction lens is also left-right asymmetric with respect to the center of the divided area. With such an exposure apparatus, a continuous high-quality color image without landing deviation near the boundary of the divided area of the screen can be obtained. A displayable color cathode ray tube can be manufactured.

In an exposure apparatus having three exposure optical systems in a color cathode ray tube of a scanning horizontal stripe type having three or more divisions, it is possible to correct the landing deviation due to the panel deformation based on the same idea. Needless to say.

The present invention is not limited to the above-described embodiment, but can be variously modified within the scope of the present invention. For example, without being limited to the above-described embodiment, the number of divided areas of the phosphor screen can be arbitrarily set, and a pair of landing correction lenses having a symmetrical positional relationship with respect to the panel center with respect to the optical axis. It suffices that the cross-sectional shape be asymmetrical left and right, and that the central landing correction lens disposed opposite the panel center have a cross-sectional shape symmetrical with respect to the optical axis.

In the above-described embodiment, the fluorescent screen is divided into a plurality of divided areas arranged in the longitudinal direction of the panel and scanning is performed. However, the present invention is not limited to this. They may be set side by side in the axial direction. In this case, the boundaries between the divided regions extend along the long axis.

Further, in the above-described embodiment, a landing correction characteristic due to panel concave deformation caused by atmospheric pressure is added to the landing correction lens among a plurality of optical members of the exposure apparatus. 5
It may be added to 5a and 65a. The cross-sectional shape is asymmetrical with respect to each optical axis, and the lens thickness on the panel center side is small. For example, a lens as shown in FIG. Alternatively, the elements of the landing characteristics described above may be added to the σ lenses 53 and 63 of each optical system. Alternatively, a correction member other than the above-described lens may be used.

Further, in the above-described embodiment, a plurality of light sources are provided for each optical system. However, the light branched from one light source may be guided to each optical system using an optical fiber branched into a plurality of light sources. . Furthermore, instead of using a plurality of correction lenses having correction characteristics that are asymmetrical with respect to the optical axis, a single correction lens is used as correction means for correcting the trajectory of each ultraviolet light emitted from a plurality of light sources. Is also good. In this case, a single correction lens has correction characteristics that are symmetric with respect to the panel center.

Finally, although the term "symmetric" has been used, the term includes a slight asymmetry (less than 20 μm landing deviation) due to various manufacturing factors.

[0072]

As described above, the exposure apparatus of the present invention applied to the color cathode ray tube of the divisional scanning system has the above-described configuration and operation, so that the boundary between a plurality of divisional regions can be obtained. A fluorescent screen capable of outputting a continuous high-quality image without deviation can be formed. This provides a color cathode ray tube of a division scanning method in which a single phosphor screen is divided into a plurality of divided regions and scans, and can display a continuous color image without deviation between the divided regions. it can.

[Brief description of the drawings]

FIG. 1 is a perspective view showing a color cathode ray tube of a two-division system in which two electron guns are arranged side by side.

FIG. 2 is a front view showing a panel of the color cathode ray tube of FIG. 1;

FIG. 3 is a cross-sectional view of the color cathode ray tube of FIG. 1 cut along a long axis.

FIG. 4 is a diagram for explaining the amount of deformation of the panel in the Z direction due to the influence of atmospheric pressure.

FIG. 5 is a diagram for explaining an amount of change in landing of an electron beam caused by deformation of the panel of FIG. 4;

FIG. 6 is a sectional view showing an exposure apparatus according to the embodiment of the present invention.

FIG. 7 is a view for explaining correction characteristics of a landing correction lens incorporated in the exposure apparatus of FIG. 6;

FIG. 8 is a sectional view showing an exposure apparatus according to another embodiment of the present invention.

FIG. 9 is a sectional view showing a geomagnetic correction lens having a riding correction characteristic.

FIG. 10 is a diagram showing a variation distribution of landing in a two-part scanning horizontal stripe type color cathode ray tube.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 10 ... Vacuum envelope, 12 ... Panel, 14 ... Rear envelope, 15 ... Phosphor screen, 16 ... Funnel, 18 ... Face plate, 20 ... Skirt part, 22 ... Neck, 24 ... Electron gun assembly, 28 ... Deflection Apparatus, 30: shadow mask structure, 32: holder, 34: stud pin, 36: shadow mask, 38: mask frame, 40: non-porous part, 41: boundary area, 42: electron beam passage hole, 50, 60: exposure Device, 51, 61: Frame, 52, 62: Light source, 53, 63: σ lens, 54, 64: Landing correction lens, 55, 65: Geomagnetic correction lens, 56, 66: Light amount distribution correction filter, A, B: Division area, C: boundary, X: major axis, Y: minor axis.

 ────────────────────────────────────────────────── ─── Continuing on the front page (72) Inventor Takashi Nishimura 1-9-2 Hara-cho, Fukaya-shi, Saitama F-term in Fukaya factory, Toshiba Corporation (reference) 5C028 GG01 GG04 GG08

Claims (6)

[Claims] 1. A method of manufacturing a color cathode-ray tube of a divisional scanning system in which a phosphor screen is divided into a plurality of divided areas and scanned, and a plurality of color images drawn in each divided area are combined and displayed as one color image. An exposure apparatus for exposing a photosensitive material applied to an inner surface of a panel of a vacuum envelope of the color cathode ray tube to form the fluorescent screen, wherein the photosensitive material is A holding member for holding, at a predetermined exposure position, a panel mounted with a shadow mask having a large number of electron beam passage holes opposed to the coated inner surface; and a predetermined exposure position provided corresponding to the plurality of divided areas. Exposure light is irradiated toward the inner surface of the panel held in each, through a number of electron beam passage holes of the shadow mask, the photosensitive material applied to the inner surface to the plurality of divided areas A plurality of light sources for dividing and exposing each of the plurality of light sources; and a plurality of corrections respectively provided between the respective light sources and the shadow mask corresponding to the plurality of light sources, and respectively correcting the trajectories of the exposure light to correct the landing. Means,
An exposure apparatus, wherein at least two of the plurality of correction units have landing correction characteristics that are asymmetric in the direction in which the plurality of divided regions are arranged with respect to the optical axis of the corresponding light source. 2. The at least two correction means each include a correction lens having a correction characteristic that is asymmetric in a direction in which the plurality of divided regions are arranged with respect to an optical axis of a corresponding light source. 2. The exposure apparatus according to claim 1, wherein the exposure apparatus has an asymmetric cross-sectional shape thinned in a central axis direction. 3. A first correction means of the plurality of correction means, which is disposed at a position shifted in a direction in which the plurality of divided regions are arranged with respect to a center axis of the panel, is arranged with respect to an optical axis of a corresponding light source. The second correction means, which is disposed at a position facing the center axis of the panel, of the plurality of correction means, with respect to the optical axis of the corresponding light source. 2. An exposure apparatus according to claim 1, wherein the exposure apparatus has landing correction characteristics symmetrical in the arrangement direction. 4. The first correction means has a first correction lens having a cross-sectional shape that is asymmetric in the arrangement direction with respect to the optical axis, and the second correction means has the arrangement direction with respect to the optical axis. The exposure apparatus according to claim 3, further comprising a second correction lens having a symmetrical cross section. 5. A method of manufacturing a color cathode ray tube of a divisional scanning system in which a phosphor screen is divided into a plurality of divided areas and scanned, and a plurality of color images drawn in each divided area are combined and displayed as one color image. An exposure apparatus for exposing a photosensitive material applied to an inner surface of a panel of a vacuum envelope of the color cathode ray tube to form the fluorescent screen, wherein the photosensitive material is A holding member for holding, at a predetermined exposure position, a panel mounted with a shadow mask having a large number of electron beam passage holes opposed to the coated inner surface; and a predetermined exposure position provided corresponding to the plurality of divided areas. Exposure light is irradiated toward the inner surface of the panel held in each, through a number of electron beam passage holes of the shadow mask, the photosensitive material applied to the inner surface to the plurality of divided areas A plurality of light sources for dividing and exposing each of the plurality of light sources; and a plurality of corrections respectively provided between the respective light sources and the shadow mask corresponding to the plurality of light sources, and respectively correcting the trajectories of the exposure light to correct the landing. Means,
Having a plurality of correction means, after forming a phosphor screen on the inner surface of the panel, when the panel is assembled as the vacuum envelope and deformed by atmospheric pressure, due to this deformation,
An exposure apparatus having an asymmetric landing correction characteristic for correcting a change in landing. 6. Each of the correction means includes a correction lens having a correction characteristic that is asymmetric with respect to an optical axis of each of the plurality of light sources in a direction in which the plurality of divided areas are arranged. 6. The exposure apparatus according to claim 5, wherein the exposure apparatus has an asymmetric cross-sectional shape thinned in an axial direction.