JPH11144616A - Manufacture of, color picture tube and manufacturing device thereof - Google Patents

Abstract

PROBLEM TO BE SOLVED: To correct the mislanding of various inverted trancated chevron shapes patterns and to easily and economically provide a color picture tube with high image quality. SOLUTION: A fluorescent screen is formed by exposing a photosensitive coating film inside a face panel 8 with light emitted from a light source 1 through a slit plate 2 and a correction lens system 6 which are successively installed between the light source 1 and the face panel 8 of a color picture tube. The correction lens system 6 is composed of a first correction lens 3 whose inner and outer surface are spherical to lead an exposure beam emitted from the light source 1 along the path of an electron beam, a second aspheric correction lend 4, and a wedge-shaped correction lens 5 to correct the mislanding of inverted trancated chevron patterns, inclining along the short side direction of the face panel 8.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for manufacturing a color picture tube used as a computer monitor or a high-definition display, and more particularly to a method for exposing and forming a fluorescent screen of the color picture tube. The present invention relates to a manufacturing apparatus, particularly to an exposure apparatus for exposing and forming a phosphor screen.

[0002]

2. Description of the Related Art As a method of manufacturing a color picture tube, when a phosphor screen is formed on the inner surface of a face panel, a photographic exposure method is usually employed. In this method, after a coating film of a photosensitive material is formed on the inner surface of the face panel, light from an exposure light source is used to expose a shadow mask as an exposure mask, and a black film called a black matrix or a fluorescent film is formed by a subsequent development process. It is for forming a body dot pattern or stripe pattern into a desired shape.

At this time, in order to cause the electron beam to accurately strike a predetermined phosphor position in the actual operation state of the color picture tube, the trajectory of the exposure light beam at the time of exposure must be changed to the trajectory of the electron beam after the completion of the color picture tube. Must match
The trajectory of an exposure light beam is corrected by one or two or more optical correction lenses.

However, in practice, during a heating process such as a joining process of a face panel and a funnel during a manufacturing process of a color picture tube or a heating process such as an exhausting process, the position of the shadow mask is inclined or rotated due to thermal deformation. This causes a so-called mislanding in which the electron beam does not accurately strike a desired phosphor.

[0005] One such mislanding is:
There is a "reverse-C" pattern. The mislanding of this "reverse C-shaped" pattern is achieved by attaching a deflection yoke to the color picture tube and setting points a and b on the screen of the color picture tube shown in FIG.
When the landing at points c and c is adjusted, the electron beam mislandes outward at points d and e in the upper half of the screen, as shown by the arrows in FIG. At points f and g, the electron beam mislandes inward. The mislanding of the "reverse C" pattern cannot be completely eliminated only by adjusting the mutual position of the color picture tube and the deflection yoke. In order to correct mislanding, a phosphor film having an asymmetric phosphor pattern is formed in advance.

FIG. 5 shows the concept of a conventional method of manufacturing a color picture tube for correcting mislanding of a "reverse V-shape" pattern.
Is shown schematically in FIG.

In FIG. 5, an exposure light beam (not shown) emitted from an exposure light source 10 is defined by a spherical correction lens 12 and an aspheric correction lens 13 after the shape of the exposure light source is defined by a slit 11. Lens system 14
The electron beam is corrected so as to coincide with the electron beam trajectory, and is applied to the inner surface of the face panel 16 via the shadow mask 15. Here, the spherical correction lens 12 is different from the one in which the commonly used inner curved surface and outer curved surface are concentric,
The outer curved surface 12b is decentered in the short side direction (Y direction) of the face panel during the actual operation of the color picture tube with respect to the inner curved surface 12a.

In this technique, the center of the outer curved surface of the spherical correction lens 12 is decentered in the Y-axis direction from the center of the inner curved surface, so that a region on the Y side with respect to an XZ plane (not shown) formed by the X axis and the Z axis. Exposure light rays passing through the Y-side area are refracted in a direction away from the Y-axis by utilizing the fact that the thickness and the inner surface inclination of the correction lens 12 increase in the upper half of the color picture tube face panel 16. In this method, the phosphor dot pattern of the phosphor film is shifted outward from the center of the panel.

[0009]

However, in the above-mentioned conventional method of manufacturing a color picture tube, in order to correct mislanding of the "reverse-C" pattern, the inner and outer curved surfaces corresponding to each mislanding pattern are corrected. Since a spherical correction lens having a different shape and a different degree of eccentricity is required, there is no versatility as a correction lens having a “reverse C-shaped” pattern.

In addition, various types of spherical correction lenses that are difficult to produce themselves are required, and the center axis (Z axis) of the exposure system is strictly matched and adjusted each time the spherical correction lens is replaced. However, the setting work is difficult, and as a result, the production cost of the color picture tube is increased.

Therefore, the present invention can easily correct mislanding of various "inverted V-shape" patterns, and can easily produce a color picture tube having high image quality without mislanding. It is an object of the present invention to provide a color picture tube manufacturing method and a color picture tube manufacturing apparatus.

[0012]

In order to achieve the above object, the present invention illuminates a phosphor screen with light emitted from a light source through a plurality of correction lenses, and exposes a photosensitive coating film on the phosphor screen. In the method for manufacturing a color picture tube described above, at least one of the correction lenses is formed in a wedge shape inclined along a short side direction of a face panel of the color picture tube.

According to the method of manufacturing a color picture tube of the present invention, mislanding of various "reverse V-shape" patterns can be corrected by simple adjustment, and a color picture tube with high image quality can be obtained. It can be easily manufactured.

The apparatus for manufacturing a color picture tube according to the present invention includes a light source, a table for holding a face panel of the color picture tube, and a plurality of correction lenses between the light source and the table. At least one of the correction lenses is formed in a wedge shape inclined along a short side direction of the face panel.

[0015]

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a perspective view of a color picture tube manufacturing method according to an embodiment of the present invention;

FIG. 1 is a schematic diagram showing the principle of a method for manufacturing a color picture tube according to the present embodiment. As shown in FIG.
In the method of manufacturing a color picture tube according to the embodiment of the present invention, the light emitted from the light source 1 is supplied to the slit plate 2 and the correction lens which are sequentially provided between the light source 1 and the panel 8 of the color picture tube. A fluorescent screen is formed by exposing a photosensitive coating film (not shown) on the inner surface of the panel 8 through the system 6.

The light source 1 is a tubular high-pressure mercury lamp that is long in the long side direction (X-axis direction) of the color picture tube panel 8, and the slit plate 2 is arranged in a direction perpendicular to the light source 1, that is, the color picture tube panel. It has an elongated opening in the short side direction (Y-axis direction), and the light emitting area of the light source 1 is defined as a substantially square shape.

The correction lens system 6 includes a first correction lens 3 having a spherical inner and outer surface for causing the exposure light beam to follow the trajectory of the electron beam from the light source 1 side, and a second correction lens 4 having an aspherical surface. The wedge-shaped correction lens 5 for correcting the mislanding of the “reverse C-shape” pattern. Each of these correction lenses is made of a glass material such as quartz glass or borosilicate crown, or a transparent member such as a resin material.

Here, since the first correction lens 3 is constituted by a spherical surface whose inner surface and outer surface have the same central axis, its manufacture is extremely easy as compared with the above-mentioned prior art correction lens 12. It is.

The wedge-shaped correction lens 5 includes a lower surface 5a substantially parallel to the face panel 8 and an upper surface 5b as an inclined surface inclined in the short side direction (Y-axis direction) of the face panel 8. ing.

The face panel 8 of the color picture tube has a photosensitive coating (not shown) formed on its inner surface by applying a photosensitive liquid, and a shadow mask 7 is fixed inside the panel 8 in a normal state. And functions as an exposure mask for the photosensitive coating film. The face panel 8 is placed on a table 9 having a movable function so as to be able to appropriately change the relative position with respect to the light source 1 at the time of exposure, with its position being regulated accurately.

In each of the steps other than the above-described method of forming the fluorescent screen, a color picture tube is manufactured by the same method as a normal method of manufacturing a color picture tube.

That is, after forming a photosensitive film by applying a coating solution containing a photosensitive material to the inner surface of the face panel, the black film and the red film are formed by the above method of exposing and forming a phosphor dot pattern at a predetermined position.・ Three phosphor films of blue and green are sequentially formed. After that, the color picture tube undergoes a sealing process of sealing the face panel and the funnel with frit glass, a sealing process of enclosing an electron gun in a neck portion of the funnel, an exhaust process of evacuating the inside of the tube, and a predetermined finishing process. Is completed.

Next, the standard of the color picture tube is 36 cm (1
The shape and dimensions of each member suitable for use in the method of manufacturing a color picture tube according to the present invention will be described by taking a case of (5 inches) -90 ° as a specific example.

The light source 1 has a diameter of 6 mm and a length of about 20
Using an ultra-high pressure mercury lamp with a substantially tubular light emitting part of mm,
The tube axis is aligned with the X axis (XX ′) along the long side of the face panel 8.
Direction).

The slit plate 2 is a flat plate, and is a Z-axis (Z-axis) which is a central axis of an exposure system in the color picture tube manufacturing method of the present invention.
Z ') is in a plane perpendicular to the opening, the opening is a strip type, and the longitudinal direction is a direction substantially orthogonal to the light source of the mercury lamp.

The first correction lens 3 is a lens whose outer surface is a perfect spherical surface, and whose inner surface has a curved surface whose cross sections in the X-axis direction and the Y-axis direction are arcs having independent radii, respectively, and the central axes of the inner surface and the outer surface. Corresponds exactly to the Z axis.

The second correction lens 4 is an aspheric lens having a flat bottom surface and an aspheric upper surface. For example, such an aspheric surface can be formed by combining fine flat surfaces.

The correction lens 5 is a wedge-shaped lens having an upper surface 5a and a lower surface 5b, each of which is flat. The lower surface 5b is perpendicular to the Z-axis, and the upper surface 5a and the lower surface 5b are 26
The slope from Y ′ to Y,
That is, when the color picture tube is actually operated, the upper side of the face panel is in a direction in which the lens becomes thicker.

The principle by which this wedge-shaped correction lens 5 can correct the mislanding of the "reverse V-shape" pattern will be described with reference to FIGS.

FIG. 2A is a top view of the wedge correction lens 5. This wedge-shaped correction lens 5 has a diameter of about 1
It has a substantially disk shape of 40 mm, and its lower end is cut linearly in order to correctly regulate the direction of rotation of the correction lens. The thickness of the wedge-shaped correction lens 5 is 1.97 mm at the thinnest lower end, 2.50 mm at the center, and 3.03 mm at the thickest upper end, and has a uniform thickness in the horizontal direction (X-axis direction). Have.

FIG. 2B is a sectional view in the Y-axis direction (YY ') at the center of the wedge-shaped correction lens 5 in the X-axis direction.
The trajectory of the light beam when the correction by the wedge correction lens 5 shown by the solid line B is performed is closer to the Y direction than the trajectory of the light beam without this lens shown by the dotted line A. It can be seen that the light is corrected to be emitted. For this reason, the phosphor pattern on the phosphor screen formed on the face panel 8 shifts in the Y direction on the entire face panel 8.

FIGS. 3 (a) and 3 (b) show the wedge correction lens 5 in FIG.
3 shows a cross section in the X-axis direction at X1 ′ and X2-X2 ′.
Also in this case, the dotted lines a represent the wedge-shaped correction lens 5 respectively.
The solid line B indicates the light beam direction after the correction by the wedge-shaped correction lens 5.

In FIGS. 3A and 3B, the position of the virtual emission point “O” of the exposure light beam emitted from the wedge-shaped correction lens 5 is determined by the thickness of the lens. It can be seen that it moves to the side closer to the face panel (upper side in the figure) and becomes “O ′” and “O ″” as compared with the case where there is no face panel. Here, the thickness of the wedge-shaped correction lens 5 is thicker on the X1-X1 ′ plane than on the X2-X2 ′ plane, so that the shift amount of the virtual emission point of the exposure light beam is X2-X2 ′. X1 than the shift amount “O” −O ”
The shift amount “O′-O” at −X1 ′ is larger.
As a result, the exposure light beam that has passed through the same beam passage opening of the shadow mask 7 mounted on the face panel 8 is more outward in the X-axis direction on the side where the thickness of the wedge correction lens 5 is thick, that is, above the phosphor screen, that is, Irradiation is performed in a direction away from the Y axis.

Therefore, the positions of the phosphor dots formed in the X-axis direction on the face panel 8 are corrected such that the upper side of the face panel in the actual operation of the color picture tube shown in FIG. Therefore, even if the electron beam is shifted in the direction in which the mislanding of the “reverse C” pattern occurs, the electron beam will eventually hit the correct phosphor, and a maximum of 10 μm when the wedge correction lens is not used. The generated mislanding amount can be completely corrected.

The shift of the irradiation position of the exposure light beam upward in the face panel by using the wedge-shaped correction lens can be corrected by appropriately adjusting the position and inclination of the face panel.

As described above, according to the method of manufacturing the color picture tube according to the embodiment of the present invention, the mislanding of the "reverse C-shaped" pattern can be achieved by adding the wedge-shaped correction lens to the exposure optical system. Can be corrected.

In addition, the amount of mislanding generated for each type of color picture tube is measured, and the magnitude of the amount of mislanding between the upper surface and the lower surface of the screen, that is, the "reverse C-shape"
It can be easily handled by appropriately adjusting the inclination angle of the wedge-shaped correction lens, which is easy to produce, according to the strength of the degree of the pattern. Further, since the wedge-shaped correction lens can be adjusted independently of a normal correction lens group for adjusting the irradiation direction of the exposure light beam, it is not necessary to perform strict axial adjustment of the correction lens as in the related art, and The mislanding correction amount can also be adjusted by relatively changing the position on the Z-axis which is the center axis of the wedge-shaped correction lens and the exposure system.

Further, the position of a spring for fixing the shadow mask of the color picture tube to the inner surface of the face panel,
Depending on the strength, the mislanding in the so-called "U-shaped" pattern in which the mis-landing direction is reversed, or the "L-shaped" pattern including a rotation component that causes the amount of mislanding to be asymmetrical on the left and right sides of the screen Can be easily coped with simply by adjusting the inclination direction of the wedge-shaped correction lens.

In the above embodiment of the present invention, the correction lens system 6 includes the first correction lens 3 which is a spherical lens, the second correction lens 4 which is an aspheric lens, and the wedge correction lens 5. Although the configuration is shown, the present invention is not limited to this. In short, the present invention can be similarly achieved by adding a wedge-shaped correction lens in an exposure system without normal correction.

Further, in the above-described embodiment of the present invention, an example is described in which the wedge-shaped correction lens is provided at a position closest to the face panel in the correction lens system, but the present invention is not limited to this. Absent.

Further, the wedge-shaped correction lens is not limited to the one using only one lens, but two or more correction lenses can be combined. According to this method, the inclination of the face panel in the short side direction is reduced. By adjusting the degree, the mislanding of a complicated “C” pattern having a different spread depending on the vertical position of the face panel can be corrected.

[0043]

As described above, according to the method for manufacturing a color picture tube and the apparatus for manufacturing the same of the present invention, a simple structure in which an inexpensive and easily formed wedge correcting lens is added to an exposure optical system has a simple structure. It is possible to correct the mislanding of the "reverse V-shaped" pattern.

Further, it is possible to easily cope with the case where the size, direction, etc. of the "reverse C-shaped" pattern are different.
Since mislanding of any “reverse C” pattern can be corrected, a color picture tube with high image quality can be obtained.

[Brief description of the drawings]

FIG. 1 is a schematic view showing a concept of an exposure system used in a method of manufacturing a color picture tube according to an embodiment of the present invention.

FIG. 2 is a diagram showing a top view and a Y-axis direction cross-sectional view of a wedge-shaped correction lens.

FIG. 3 is a diagram showing a cross-sectional view in the X-axis direction of a wedge-shaped correction lens.

FIG. 4 is a diagram showing a mislanding of a “reverse C-shaped” pattern;

FIG. 5 is a schematic view showing the concept of an exposure system used in a conventional color picture tube manufacturing method.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Light source 5 Wedge correction lens 6 Correction lens system 8 Face panel

Claims (2)

[Claims] 1. A method for manufacturing a color picture tube for irradiating a phosphor screen with light emitted from a light source via a plurality of correction lenses and exposing a photosensitive coating film on the phosphor screen, wherein A method for manufacturing a color picture tube, characterized in that at least one sheet is formed in a wedge shape inclined along a short side direction of a face panel of the color picture tube. 2. A light source, a table for holding a face panel of a color picture tube, and a plurality of correction lenses between the light source and the table, wherein at least one of the correction lenses is: An apparatus for manufacturing a color picture tube, wherein the face panel is formed in a wedge shape inclined along a short side direction of the face panel.