JP2001343756A - Exposure device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To uniformly expose the fluorescent surface of a panel of a color image picture tube. SOLUTION: An exposure device 10 has a support base 12 for positioning a panel 1, a light source L and plural correction lenses 16a, 16b, 16c and 16d which correct the orbit of light. The flanks or non-use regions of the at least one correction lenses are subjected to black coating. The scattering of the unwanted light in exposure reduced, and the illuminance of the exposure range on the inside surface of the panel 1 is readily optimized and the satisfactory fluorescent surface 3 may be formed.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to, for example, an exposure apparatus for forming a fluorescent screen of a color picture tube.

[0002]

2. Description of the Related Art Generally, a color picture tube has a deflecting yoke in which a phosphor screen is formed on an inner surface of a panel constituting an envelope and an electron beam emitted from an electron gun is mounted outside the envelope. Is deflected by the magnetic field generated, and the phosphor screen is horizontally and vertically scanned through a shadow mask, thereby displaying a color image on the phosphor screen.

[0003] As the above-mentioned phosphor screen, blue, green,
A phosphor screen composed of a three-color phosphor layer in the form of dots or stripes emitting red light, or a black light absorbing layer in the gap between the phosphor screen composed of the three-color phosphor layer and the three-color phosphor layer described above. A provided phosphor screen called a black matrix type or a black stripe type is known.

[0004] Further, these phosphor screens are conventionally formed by a photographic printing method. That is, for a phosphor screen composed of a three-color phosphor layer having no light absorption layer, a phosphor slurry of a specific color and a photosensitive agent as a main component is applied to the inner surface of the panel to form a phosphor slurry layer. Then, this phosphor slurry layer is exposed through a shadow mask and developed to form a phosphor layer of a predetermined pattern, and this is repeated for each color to form phosphor layers of three colors. For a black matrix type or black stripe type fluorescent surface having a light absorbing layer, a photosensitive agent is applied to the inner surface of the panel to form a photosensitive film before the above-described three color phosphor layers are formed. The photosensitive film is exposed and developed to form a resist having a dot or stripe pattern at the position where the phosphor layer is to be formed. Next, a black paint is applied to the inner surface of the panel on which the resist is formed to form a light absorption layer which is a black paint layer. Thereafter, a phosphor layer is formed in the gap between the light absorbing layers by the same method as the above-described method of forming the three-color phosphor layer, thereby forming a phosphor screen.

[0005] In such a phosphor screen forming method, an exposure apparatus is used when exposing a phosphor slurry layer or a photosensitive film formed on the inner surface of the panel. As shown in FIG. 10, this exposure apparatus usually has a support 2 for positioning and supporting the panel 1. A phosphor slurry formed by applying the inner surface of the panel 1 to the inside of the lower portion of the support 2. A light source 5 for irradiating the layer 3 or the photosensitive film with light through a shadow mask 4, and a first correction lens for matching the trajectory of the light emitted from the light source 5 with the trajectory of the electron beam emitted from the electron gun 6a, a second correction lens 6b, and a third correction lens for correcting the influence of the vertical component of terrestrial magnetism on the electron beam.
In the exposure table using a long light source, the projection shape of the light source on the inner surface of the panel is corrected by the curved surface shape of the inner surface of the panel 1 on the exposure table using the long light source. Therefore, a configuration in which the fourth correction lens 6d is arranged is also known. In addition, each correction lens 6a, 6b,
Each of the lenses 6c has a thickness of about 1 mm to 10 mm, and a round or square lens is used.

As described above, to form the fluorescent screen of the color picture tube, a phosphor slurry layer coated on the inner surface of the panel or a shadow mask is formed on the photosensitive film on the inner side of the lower portion of the support for positioning and supporting the panel. An exposure apparatus is used in which a light source for irradiating light through the light source and a correction lens for aligning the trajectory of the light emitted from the light source with the trajectory of the electron beam emitted from the electron gun are used.

However, when the light emitted from the light source passes through the correction lens and the light reflected in the lens leaks out of the lens from the side wall of the lens, the uniformity of the exposure illuminance within a desired exposure range is reduced. I do. Then, when the uniformity of the exposure illuminance within the exposure range is reduced, in the light absorbing layer forming step, the photosensitive film for forming the black matrix type or black stripe type light absorbing layer becomes non-uniform, and The area and width of the light absorbing layer become non-uniform, which causes deterioration of color purity. Similarly, in the step of forming the phosphor layer, if the uniformity of the exposure illuminance within the exposure range is reduced, the sensitivity of the phosphor slurry layer becomes nonuniform, and the thickness of the phosphor slurry layer becomes nonuniform. Color deterioration. Furthermore, when the light leaked from each correction lens exposes the photosensitive film or the phosphor slurry layer outside the desired exposure range, there is a problem that a phosphor screen is formed in an inappropriate area. . Such a phenomenon is remarkable in a large-sized tube in which it is necessary to increase the illuminance of the light source or a wide-angle deflection tube exposure apparatus in which the angle of incidence of light from the light source on the lens is large.

In a color picture tube provided with an in-line type electron gun in which a side gun is arranged in a longitudinal direction of a screen with respect to a center gun, a light source corresponding to an electron gun arrangement of the color picture tube is used when exposing a fluorescent screen. The photosensitive film and the phosphor slurry layer corresponding to the side gun are exposed while being displaced in the direction of the long axis of the screen, that is, the y direction shown in FIG. Therefore, the half surface of the screen on which the light source is displaced has a longer distance from the light source than the other half surface, and the illuminance at the time of exposure relatively decreases. The illuminance difference at the time of exposure increases as the distance from the long axis of the screen increases, and becomes remarkable in a large tube having a large screen size or a wide-angle deflection tube having a large deflection angle.

As described above, in the color picture tube provided with the in-line type electron gun, when exposing the phosphor screen, the light source is displaced in the longitudinal direction of the screen which is the direction corresponding to the arrangement of the electron guns of the color picture tube. The photosensitive film and the phosphor slurry layer corresponding to the gun are exposed. Therefore, the half surface of the screen on which the light source is displaced has a longer distance from the light source than the other half surface, and the illuminance at the time of exposure relatively decreases. And
The illuminance difference at the time of exposure of the side gun causes an imbalance in the exposure of the photosensitive film of a color corresponding to the side gun from the middle part of the screen long axis to the end of the long axis. This causes a problem that the effective light emitting area of the phosphor is small and causes deterioration of color purity. The illuminance difference at the time of exposure increases as the distance from the long axis of the screen increases, and becomes remarkable in a large tube having a large screen size or a wide-angle deflection tube having a large deflection angle.

[0010]

As described above, the exposure apparatus used for forming the fluorescent screen of the color picture tube is provided with a fluorescent coating formed on the inner surface of the panel inside the lower part of the support base for positioning and supporting the panel. A light source that irradiates the body slurry layer or the photosensitive film with light through a shadow mask, and a correction lens for aligning the trajectory of the light emitted from the light source with the trajectory of the electron beam emitted from the electron gun are arranged. But
When light emitted from the light source passes through the correction lens, if light reflected in the lens leaks out of the lens from the side wall of the lens, the uniformity of exposure illuminance within a desired exposure range decreases, and the photosensitive film or There is a problem that the photosensitivity of the phosphor slurry layer becomes non-uniform and the color purity is reduced. In a color picture tube provided with an in-line type electron gun in which a side gun is arranged in a screen long axis direction with respect to a center gun, a light source is displaced in a screen long axis direction which is a direction corresponding to an electron gun arrangement of the color picture tube. Then, to expose the photosensitive film and the phosphor slurry layer corresponding to the side gun, the half surface of the screen on which the light source is displaced is farther from the light source than the other half surface, and the illuminance during exposure is relatively high. Decline. The illuminance difference at the time of exposure of the side gun causes an imbalance in the exposure of the photosensitive film of a color corresponding to the side gun from the middle portion of the screen to the end portion of the long axis from the middle portion of the long axis of the screen, thereby causing deterioration of color purity. have.

SUMMARY OF THE INVENTION The present invention has been made in view of the above circumstances, and an object of the present invention is to provide an exposure apparatus with high accuracy for correcting light from a light source with a correction lens.

[0012]

An exposure apparatus according to the present invention comprises a light source, a correction lens provided with an effective use area for correcting the trajectory of light emitted from the light source, and a correction lens provided outside the effective use area of the correction lens. And a leakage suppressing means for suppressing light leakage. In this configuration, the trajectory of the light emitted from the light source is corrected by the correction lens, and the exposure target is exposed. Unnecessary leakage light from the correction lens is reduced by the leakage suppression means provided outside the effective use area of the correction lens, so that high-precision exposure is possible, and a high-quality product is provided.

[0013] The leakage suppressing means is easily formed by using a black paint film.

Further, the leakage suppressing means is provided by providing a black coating film on the surface of the uneven portion formed on the correction lens,
A black paint film is firmly attached to the correction lens.

A panel of a color picture tube as an object to be exposed is supported by a supporting means, and an inner surface of the panel is exposed to form a phosphor screen having uniform and high color purity.

Further, the exposure apparatus of the present invention comprises a supporting means for supporting an object to be exposed, a light source, a correction lens for correcting the trajectory of light emitted from the light source and irradiating the object with the light, And a light absorbing means provided in the correction lens and having different light transmission distributions set according to the positions of the light source and the object to be exposed. In this configuration, the trajectory of the light emitted from the light source is corrected by the correction lens, and the exposure target is exposed. By the light absorbing means provided in the correction lens, the light transmission amount is adjusted according to the positions of the light source and the object to be exposed, so that high-precision exposure is possible, and a high-quality product is provided.

The exposure apparatus of the present invention is an exposure apparatus for exposing a fluorescent screen of a panel of a color picture tube provided with an in-line type electron gun in which a side gun is arranged in a longitudinal direction of a screen with respect to a center gun, A light source for exposing each color phosphor, a correction lens for correcting the trajectory of light emitted from the light source, and light absorbing means provided on the correction lens and having different light transmission distributions set along the long axis direction. It is provided. In this configuration, the trajectories of the light of the light source radiated from a plurality of positions corresponding to the center gun and the side gun are corrected by the correction lens, and the fluorescent screen of the panel of the color picture tube is exposed. By the light absorbing means provided in the correction lens, the light transmission amount is adjusted according to the positions of the light source and the object to be exposed, so that high-precision exposure is possible, and a high-quality product is provided.

The light absorbing means sets a different light transmission distribution for each half surface sandwiching the short axis, and sets a transmittance distribution that decreases in accordance with the distance from the short axis on one half surface in the long axis direction. be able to.

[0019]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, an embodiment of the exposure apparatus of the present invention will be described with reference to the drawings.

The panel 1 of a color picture tube, which is a cathode ray tube as an object to be exposed, is the same as that shown in FIG. 10 and has red (R), red (R), A phosphor screen 3 is formed in which phosphor layers of three colors of green (G) and blue (B) and a light absorbing layer are formed in a predetermined pattern. After the panel 1 is combined with the shadow mask 4 on the inside, it is combined with a funnel to form an envelope, and the electron gun is sealed to form a color picture tube. In addition, this electron gun has an in-line type electron gun in which red (R) and blue (B) side guns are arranged in a horizontal plane, that is, in the longitudinal direction of the screen, with respect to a green (G) center gun. Has become.

In FIG. 1, reference numeral 10 denotes an exposure apparatus. The exposure apparatus 10 has a support table 12 as a support means for positioning and supporting the panel 1. The support table 12 faces the inner surface of the panel 1. An opening 12a is formed. On the inner side of the lower portion of the support table 12, a phosphor slurry layer or a photosensitive film coated on the inner surface of the panel 1
A first correction lens 16a, a second correction lens 16b for matching the trajectory of light emitted from the light source L with the trajectory of the electron beam emitted from the electron gun, A third correction lens 16c for correcting the influence of the vertical component of the terrestrial magnetism on the beam, a correction lens 17 including a fourth correction lens 16d for correcting the shape of the light source L projected on the inner surface of the panel, and a filter 18 are provided. . The fourth
The correction lens 16d corrects the projected shape of the light source L on the panel inner surface due to the curved shape of the inner surface of the panel 1 on an exposure table using a long light source for forming a phosphor screen having a light absorption layer in the form of a black stripe. Therefore, it is corrected as needed. As the light source L, for example, an ultra-high pressure mercury lamp that emits light necessary for exposure is used. Further, a multilayer film is formed on a part or all of the correction lenses 16a, 16b, 16c, and 16d as necessary.

Then, the first to third correction lenses 16a, 1
As shown in FIGS. 2 and 3, reference numerals 6b and 16c denote a substantially plate-like shape such as a disk, and a rectangular effective use area used at the time of exposure.
21 is set, the periphery of this effective use area 21 is outside the effective use area 22 not used at the time of exposure, and further, the outer peripheral part is a side wall part 23 which is a side wall part along the optical axis, that is, the z axis. Has become. In this embodiment, the side surface portion 23 is coated with black paint, that is, black paint is applied to form a black paint film.
Are formed.

As shown in FIGS. 4 and 5, the fourth correction lens 16d has, for example, a substantially hemispherical curved surface portion 27, and a horizontal annular bottom surface portion 28 located at an end of the curved surface portion 27. And a side surface portion 29 that is a vertical annular side wall portion.
A black paint is applied to 28 and the side surface 29, that is, a black paint is applied to form a black paint film,
30 are formed.

As described above, according to the phosphor screen forming exposure apparatus of the color picture tube according to the present embodiment, the side surface of at least one of the plurality of lenses used for the exposure stand for the color picture tube is used. Alternatively, by applying black paint to the non-use area, that is, outside the effective use area, it is possible to reduce unnecessary light leakage from the lens side wall part and the outside of the lens effective use area at the time of exposure, and reduce unnecessary scattered light at the time of panel exposure. It is easy to optimize the illuminance on the exposure surface, which is the exposure range of the inner surface of the panel, to reduce the uneven exposure of the photosensitive film and the slurry layer, and to expose the photosensitive film or the slurry layer outside the desired exposure range. Thus, an exposure apparatus for a color picture tube capable of forming a fluorescent screen having good color purity and the like can be constructed without using the same.

That is, the first to third correction lenses 16
Since the leakage suppression means 25 and 30 are provided on the side surface 23 of the a, 16b and 16c, and on the bottom surface 28 and the side surface 29 of the fourth correction lens 16d, light emitted from the light source L is transmitted to each of the correction lenses 16a and 16b. ,
When passing through 16c and 16d, the light reflected inside the lens is leak-suppressing means 25, 30 provided on the side surface 23, 29 or the bottom surface 28.
The black paint is sufficiently shielded and absorbed, and can be prevented from leaking out of the lens. Therefore, unnecessary light reaching the desired exposure range can be blocked, and a good phosphor screen 3 can be formed.

The effect of blocking unnecessary light and forming a good phosphor screen 3 as described above is due to the fact that the incident angle of the light from the light source L to the lens or the large tube which needs to increase the illuminance of the light source L is required. This is more effective for an exposure apparatus having a wide-angle deflection tube that becomes larger.

Further, in the above embodiment, the black paint is applied to the side and bottom surfaces of the four correction lenses 16a, 16b, 16c, 16d. The same effect can be realized even if it is provided on the bottom surface. In addition, the same effect can be achieved by applying a black paint to the outside of the effective use area 22 of each correction lens together with or instead of the leakage suppressing means provided on the side surface and the bottom surface, and providing the same effect. it can.

Further, the leakage suppressing means can be easily realized by applying a black paint which blocks and absorbs light.

Further, by applying a process of forming a concave and convex portion for facilitating the application of the paint, such as a ground glass process, in the area of the lens where the black paint is applied, the effect of attaching the black paint to the lens can be improved. The leak suppressing means can be easily and firmly formed. In addition, the uneven portion and the black coating film may be identical in the entire region, or may be configured to partially overlap.

Further, the configuration of the correction lens is not limited to the above-described one, and can be applied to, for example, a configuration having only one correction lens.

Next, another embodiment of the present invention will be described with reference to FIGS. The same parts as those in the configuration shown in FIG. Also,
In this embodiment, the leakage suppressing means, the fourth correction lens 16d, and the like are not shown, but may be provided as necessary.

In this configuration, the red (R) and blue (B) side guns are arranged in a horizontal plane, that is, along the screen long axis direction, that is, along the x direction, with respect to the green (G) center gun. As shown in FIG. 6, when forming a fluorescent film of a color corresponding to one of the side guns, for example, a red (R) fluorescent film, When forming a fluorescent film of a color corresponding to the other side gun, for example, blue (B), it is displaced or moved in the plus direction, that is, the left direction along the x direction.
It is displaced or moved in the negative or right direction along the x direction.

The first to third correction lenses 16a, 16b,
The correction lens 17 having 16c is provided corresponding to the phosphor layers of three colors of red (R), green (G), and blue (B), that is, an in-line type electron gun. Here, the correction lenses do not necessarily have to be all different, for example, “A” for the first correction lens, “B” for the second correction lens, and “E” for the third correction lens during red (R) exposure. , "A" for the first correction lens at the time of green (G) exposure, "C" for the second correction lens, and "E" for the third correction lens, and the first correction at the time of blue (B) exposure. A combination such as “A” for the lens, “D” for the second correction lens, and “E” for the third correction lens can be used. In the above case, the first correction lens
The same lens 16a and the third correction lens 16c are used in correspondence to each color with a lateral displacement, and the second correction lens 16c is used.
Since b is dedicated to each color, the total number of lenses is five.

As shown in FIG. 6, the light source L is displaced to a position corresponding to the position of the red (R) side gun, that is, the illuminance of the inner surface of the panel 1 when the red phosphor is exposed. Since the area on the negative side of the x-axis is smaller than the area on the positive side of the x-axis, the first correction lens 16a corresponding to the position of the side gun for red (R) has x as shown in FIG. A light absorbing means 41, which is a light absorbing layer having a transmittance distribution characteristic in which the transmittance in the region on the negative side of the x axis is larger than that in the region on the positive side of the axis, is provided to make the illuminance on the inner surface of the panel 1 uniform.

Similarly, as shown in FIG. 7, the light source L is displaced to a position corresponding to the position of the side gun for blue (B), that is, the illuminance of the inner surface of the panel 1 when the blue phosphor is exposed. Since the area on the x-axis minus side is larger than the area on the x-axis plus side, the first correction lens 16a corresponding to the position of the side gun for blue (B) has The light absorbing means 42, which is a light absorbing layer having a transmittance distribution characteristic in which the transmittance in the region on the negative side of the x axis is smaller than that in the region on the positive side of the x axis, is provided to make the illuminance of the inner surface of the panel 1 uniform. .

As described above, according to the present embodiment, the light absorbing means having the transmittance distribution characteristic corresponding to the displacement of the light source L
By providing the first and second correction lenses 16 and 41 in the first correction lens 16a, it is difficult to correct such a configuration without the light absorbing means 41 and 42. The width of the effective light emitting region of the blue phosphor is larger than the width of the effective light emitting region of the blue phosphor, and the width of the effective light emitting region of the blue phosphor is larger than the width of the effective light emitting region of the red phosphor in the region on the x-axis minus side. The phenomenon can be eliminated, and a fluorescent screen with good color purity can be formed even in the peripheral portion of the screen without any imbalance in the effective light emitting area of the phosphor corresponding to the side gun.

The light absorbing layer constituting the light absorbing means is
It can be formed on one or both of the bottom surface of the lens, that is, the light source L side or the top surface, that is, the panel 1 side. Further, the same effect can be realized even if the light absorbing layer constituting the light absorbing means is formed only on the half surface sandwiching the short axis of the correction lens, that is, the y axis.

That is, a light source and a dedicated correction lens for correcting the trajectory of light for exposing the red, green, and blue phosphors emitted from the light source are provided.
The transmittance distribution in the direction of the long axis of the screen of the correction lens for forming the phosphor screen corresponding to the side gun is different, or different for each half surface sandwiching the short axis, or the distance from the short axis to one half surface. By forming a light absorbing layer having a transmittance distribution characteristic that becomes lower as a result, the illuminance at the time of exposing the color corresponding to the side gun, that is, the imbalance of exposure, can be eliminated even in the peripheral portion of the screen, and it corresponds to each side gun. It is possible to form a phosphor screen with good color purity by reducing the imbalance of the effective light emitting region of the color of the phosphor.

[0039]

According to the exposure apparatus of the present invention, it is possible to provide an exposure apparatus capable of correcting light from a light source with a correction lens, optimizing illuminance, and performing exposure with high accuracy.

[Brief description of the drawings]

FIG. 1 is a configuration diagram showing one embodiment of an exposure apparatus of the present invention.

FIG. 2 is a perspective view showing a correction lens of the exposure apparatus.

FIG. 3 is a partial cross-sectional view showing the same correction lens.

FIG. 4 is a perspective view showing a correction lens of the exposure apparatus.

FIG. 5 is a partial cross-sectional view showing the same correction lens.

FIG. 6 is a configuration diagram showing another embodiment of the present invention, in which a light source is moved to a position for exposing a phosphor corresponding to one side gun.

FIG. 7 is a configuration diagram showing a state in which the light source is moved to a position for exposing a phosphor corresponding to the other side gun of the above.

FIG. 8 is a graph showing a transmittance distribution characteristic of a light absorbing means provided in a correction lens for exposing a phosphor corresponding to one side gun of the above.

FIG. 9 is a graph showing transmittance distribution characteristics of light absorbing means provided in a correction lens for exposing a phosphor corresponding to the other side gun of the above.

FIG. 10 is a configuration diagram showing a conventional exposure apparatus.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Panel as an exposure object 10 Exposure apparatus 12 Support means 16a First correction lens which constitutes a correction lens 21 Effective use area 22 Outside effective use area 25 Leakage suppression means 41, 42 Light absorption means L Light source

 ────────────────────────────────────────────────── ─── Continuing on the front page (72) Inventor Masayo Inoue 1-9-9, Hara-cho, Fukaya-shi, Saitama F-term in Toshiba Fukaya Plant (reference) 2H097 AA16 BB10 LA11 5C028 GG04 GG08 GG12

Claims (8)

[Claims] 1. A light source, a correction lens provided with an effective use area for correcting the trajectory of light emitted from the light source, and a leakage suppressing means for suppressing light leakage outside the effective use area of the correction lens. An exposure apparatus, comprising: 2. An exposure apparatus according to claim 1, wherein said leakage suppressing means includes a black paint film. 3. The exposure apparatus according to claim 2, wherein the leakage suppressing means has a black coating film provided on the surface of the uneven portion formed on the correction lens. 4. A supporting means for supporting an object to be exposed,
4. The exposure apparatus according to claim 1, wherein the object to be exposed is a panel of a color picture tube. 5. A supporting means for supporting an object to be exposed, a light source, a correction lens for correcting the trajectory of light emitted from the light source and irradiating the object with the light, and a light source provided on the correction lens. An exposure apparatus comprising: a light absorbing unit in which a different light transmission distribution is set according to a position with respect to an object to be exposed. 6. An exposure apparatus for exposing a phosphor screen of a panel of a color picture tube provided with an in-line type electron gun in which a side gun is arranged in a longitudinal direction of a screen with respect to a center gun, wherein a light source for exposing each color phosphor is provided. And a correction lens for correcting the trajectory of light emitted from the light source, and light absorbing means provided on the correction lens and having different light transmission distributions set along the long axis direction. Exposure equipment. 7. The light absorbing means according to claim 6, wherein a different light transmission distribution is set for each half surface sandwiching the short axis.
Exposure apparatus according to the above. 8. The exposure apparatus according to claim 6, wherein the light absorption means has a transmittance distribution that is reduced in accordance with the distance from the minor axis on one half surface in the major axis direction.