JPH0272538A - Exposure device for forming fluorescent screen of color picture tube - Google Patents

Abstract

PURPOSE:To make dust simply removable by covering a correcting lens and a light distribution filter with a transparent film and demountably installing a dust collector which is made up of a dielectric charged with static electricity near a correcting lens and a light distribution lens. CONSTITUTION:Transparent conductive films 23a-23c are formed on the upper surfaces of correcting lenses 20 and 21 and a light distribution filter 22, respectively. This dust collector 24 is installed near the correcting lenses 20 and 21 and the light distribution filter 22. This dust collector 24 is made up of a dielectric, and this dielectric is connected to a capacitor 25 so that the former is charged with static electricity, and it can be mounted to and demounted from a frame 13. Thereby, even if dust in the air sticks to the correcting lens 20 and 21 and the light distribution filter 22, it can be simply removed.

Description

DETAILED DESCRIPTION OF THE INVENTION [Object of the Invention 1 (Industrial Application Field) This invention relates to an exposure apparatus for forming a phosphor screen of a color picture tube.

(Prior Art) Generally, as shown in FIG. 3, a color picture tube has an envelope consisting of a panel (1) and a funnel (2) integrally joined to the panel (1). Panel (1)
A phosphor screen (4) from a 63-color phosphor layer that does not emit light in blue, green, and red is placed on the inner surface of the panel (1), facing a shadow mask (3) that is mounted inside and has a large number of electron beam passage holes. )
is formed. Also, the neck of the funnel (2) (
An electron gun (6) that emits three electron beams is disposed inside the funnel (2), and the three electron beams emitted from the electron gun (6) are sent to the cone (7) and neck (5) of the funnel (2). A color image is displayed on the phosphor screen (4) by scanning the phosphor screen (4) horizontally and vertically by deflecting it with a deflection device (8) attached to the outside of the boundary. It has become.

The back of such a color picture tube, especially the electron tube (6), is an in-line electron gun that emits three electron beams consisting of a center beam and a pair of side beams that pass on the same plane, and the phosphor screen (4) is an As shown in Figure 4 (A) and (B), a dot-shaped three-color phosphor layer (10B),
(IOC), (10R) or striped three-color phosphor layers (11B), (11G), (11R), as roughly shown in Figures 5 (^) and (8), Those phosphor layers (10B), (IOG),
(IOR) or (IIB), (IIG), (11
There is one in which a black light absorbing layer (12) is provided in the gap of R).

Conventionally, the phosphor screen of this color picture tube has been formed by a photographic printing method. As shown in Figure 6, for a phosphor screen with a light absorption layer, first, a photosensitive liquid containing polyvinyl alcohol (hereinafter abbreviated as PV8) as a main component is applied to the inner surface of the panel, and then the photosensitive liquid is applied to the inner surface of the panel. The film is exposed to light through a shadow mask, and a dot-like or stripe-like pattern corresponding to the electron beam passage hole of the shadow mask is printed at the position where the three-color phosphor layer is to be formed. This is then developed. Next, a light-absorbing paint is applied to the inner surface of the panel having the developed photoresist film. After that, the photoresist film attached to the inner surface of the panel and the light-absorbing paint layer applied thereon are peeled off to create openings (dot-shaped or striped) where the three-color phosphor layer will be formed. Form a light absorption layer.

Next, a phosphor slurry containing phosphor and PVA photosensitive liquid as main components is applied to the inner surface of the panel on which the light absorption layer is formed. Next, the phosphor slurry layer is exposed to light through a shadow mask, and a pattern corresponding to the electron beam passage hole of the shadow mask is printed at the phosphor layer forming position. This is then developed.

By repeating the steps from coating the phosphor slurry to development for the three color phosphors, a phosphor screen having a light absorption layer in the gaps between the three color phosphor layers is formed.

Note that a phosphor screen without a light absorption layer is formed by repeating the steps from coating the phosphor slurry to development for three color phosphors.

FIG. 7 shows an exposure apparatus used for forming the light absorption layer and the phosphor layer. This exposure device is an exposure device for forming a phosphor screen of a color picture tube, which has an in-line electron gun.
It has a frame (13) in which a support part for positioning and supporting the panel (1) is formed in the upper part, and in the lower part of this frame (13),
A light source section (14) using an ultra-high pressure mercury lamp, a halogen lamp, or the like as a light source is provided. And this light source part (
14) to the exposed portion vi1 of the PVA photosensitive liquid or phosphor slurry formed on the inner surface of the panel (1) on the support portion.
(15), a side beam compatible γ-ΔS correction lens (16) for aligning the light from the light source section (14) with the trajectory of the electron beam, and a deflection center A T-ΔP correction lens (17) that performs correction due to the movement of the panel (1), a light distribution filter (18) that corrects the distribution of irradiation light to the exposed member layer (15) formed on the inner surface of the panel (1), and the like.

Therefore, the light emitted from the light source section (14) is transmitted through the correction lenses (16), (17) and the light distribution filter (18).
through the exposed member layer (1) on the inner surface of the panel (1) through a shadow mask (3) attached to the panel (1).
5) to print a pattern corresponding to the electron beam passing holes of the shadow mask (3) on this exposed member layer (15).

(Problems to be Solved by the Invention) As mentioned above, the exposure device for forming the phosphor screen of a color picture tube is
A correction lens, a light distribution filter, and the like are disposed at the bottom of a frame on which a support portion for positioning and supporting the panel is formed. Therefore, during exposure, dust that falls from the inside of the panel or the shadow mask adheres to the light distribution filter and correction lens, and even when not exposed, dust floating in the air adheres to the light source. The light is refracted to change its trajectory, or the light is absorbed or reflected to change the light distribution on the layer of the exposed member. As a result, the shapes of the light absorption layer and the phosphor layer deteriorate, and the quality of the phosphor screen deteriorates.

Conventionally, dust adhering to the correction lens and light distribution filter has been removed by installing an air nozzle in the exposure device and operating it as needed, or by blowing it away by an operator using an air gun. However, since the exposure apparatus uses electricity, and the correction lens and light distribution filter are made of a dielectric material, the surface thereof is charged and tends to attract dust electrostatically. In addition, there is a problem in that once the dust has adhered, it is difficult to remove it due to electrostatic adsorption.

Especially recently, there is a high demand for high resolution color picture tubes.
If the diameter of the electron beam passing hole of the shadow mask and the arrangement pitch thereof are small, even the smallest amount of dirt will adversely affect the quality of the phosphor screen.

This invention was made in view of the above problems, and
The purpose is to make the correction lens and light distribution filter less likely to attract dust, and to make it easy to remove dust if it does.

[Structure of the Invention] (Means for Solving the Problems) In an exposure apparatus for forming a color picture tube phosphor screen, which includes a correction lens and a light distribution filter disposed in a region through which light from a light source passes, the above-mentioned correction lens is provided. A transparent conductive coating was provided on the light distribution filter, and a dust collector made of a dielectric material that charges static electricity was detachably provided near the correction lens and the light distribution filter.

(Function) When a transparent conductive film is formed on a correction lens or a light distribution filter as described above, it prevents charging and eliminates the electrostatic attraction of dust, and even if dust adheres to them, it can be easily removed. can do. In addition, if a dust collector that charges static electricity is installed near the correction lens and light distribution filter, it will electrostatically attract dust floating in the air near the correction lens and light distribution filter, causing it to stick to the correction lens and light distribution filter. can be reduced.

(Example) Hereinafter, the present invention will be described based on an example with reference to the drawings.

FIG. 1 shows an exposure apparatus for forming a color picture tube phosphor screen, which is an embodiment of the present invention. This exposure apparatus has a frame (1) on which a support part for positioning and supporting the panel (1) is formed.
3), and a light source section (14) with an ultra-high pressure mercury lamp, halogen lamp, etc. as a light source at the bottom of this frame (13).
Pv is formed on the inner surface of the panel (1) positioned and supported from the light source section (14) to the support section.
^ Passage area of light emitted toward the exposed member layer (15) such as photosensitive liquid or phosphor slurry, that is, the light source part (1
4) and the shadow mask (
3), a γ-ΔS correction lens (20), a T-ΔP correction lens (21), and a light distribution filter (22) are arranged in this order from the light source section (14) side.

In particular, the correction lenses (20), (21) and the light distribution filter (22) in this example each have a transparent conductive coating (23) made of tin oxide, indium fermentation, etc. on their upper surfaces.
a), (23b), and (23c) are formed.

Further, the exposure apparatus of this example includes the above-mentioned correction lens (20).
, (21) and a dust absorber (24) is installed near the light distribution filter (22).

This dust absorber (24) is made of a dielectric material that electrostatically attracts dust, etc., and the dielectric material is connected to a capacitor (25) to charge static electricity, and is removable from the frame (13). ing.

By the way, when the exposure apparatus is configured as described above, as shown in FIG. ) Airborne debris (27a
) is electrostatically adsorbed and floating in the air (27a)
correction lens (2OL (21) and light distribution filter (2
2) Reduce adhesion to. On the other hand, the correction lens (20) (
21) and the top surface of the light distribution filter (22) are coated with transparent conductive coatings (23a), (23b), and (23c), respectively.
) are formed, so panels (1) are formed on their surfaces.
Even if dirt (27b) falls from the shadow mask (3), it will not be electrostatically attracted, and the attached dirt can be easily removed using an air gun, air nozzle, or the like. In addition, dust in the air (27) that adheres to these correction lenses (20), (21) and the light distribution filter (22)
a) can also be easily removed at the same time.

The dielectric material of the dust absorber (24) that attracts dust is
It can be recycled by removing and cleaning it at any time.

[Effect of the invention] In an exposure device for forming a phosphor screen of a color picture tube in which a correction lens and a light distribution filter are disposed in a region through which light from a light source passes, a transparent conductive film is formed on the correction lens and the light distribution filter. Then, the transparent conductive coating prevents dust from being electrostatically attracted, and even if dust falls from the inner surface of the panel or the shadow mask, it can be easily removed. In addition, if a dust collector made of a dielectric material that charges static electricity is installed near the correction lens or light distribution filter, it will attract dust floating in the air near the correction lens or light distribution filter. reduce adhesion to Furthermore, even if dust in the air were to adhere to these correction lenses or light distribution filters, it could be easily removed from the inner surface of the panel or the shadow mask in the same way as dust. Therefore, it is possible to provide an exposure apparatus that eliminates light refraction and changes in light distribution valve illumination due to adhesion of dust, and does not degrade the quality of the phosphor screen.

[Brief explanation of the drawing]

FIG. 1 is a block diagram of an exposure device for forming a phosphor screen of a color picture tube, which is an embodiment of the present invention, FIG. 2 is an enlarged view of the main parts to explain its operation, and FIG. Figures 4(A) and (8), which show the structure, are respectively a diagram of a phosphor screen made of dot-like phosphor layers and a phosphor screen made of striped phosphor layers, and FIGS. 5(A) and (8). B) The figure is a diagram of a phosphor screen consisting of a dot-shaped phosphor layer having a light absorption layer and a diagram of a phosphor screen consisting of a stripe-shaped phosphor layer having a light absorption layer, respectively. Figure 6 explains the method of forming the phosphor screen. FIG. 7 is a block diagram of a conventional exposure apparatus for forming a phosphor screen of a color picture tube. 1... Panel 3... Shadow mask 13
...Frame stand 14...Light source part 15...Exposed member 20...γ-ΔS correction lens 21...
- T-Δp correction lens 22... Light distribution filters 23a, 23b, 23c -... Transparent conductive film 24...
Dust vacuum agent agent Patent attorney Dian Hu O Hu No. 1 Figure 3 CI! Figure 4 No. 551J @ Ward 2

Claims (1)

[Claims] A light source, and a correction lens and a light distribution filter disposed in a passage area of the light emitted from the light source toward the exposed member layer formed on the inner surface of the panel; In an exposure apparatus for forming a phosphor screen of a color picture tube, which prints a pattern corresponding to a hole in a shadow mask disposed opposite to the exposed member layer on the exposed member layer using light from a light source, the correction lens and the light distribution are provided. An exposure device for forming a phosphor screen of a color picture tube, characterized in that a transparent conductive film is provided on the filter, and a dust absorber made of a dielectric material that charges static electricity is detachably installed near the correction lens and the light distribution filter.