JPS58123635A - Color picture tube exposure device - Google Patents

Abstract

PURPOSE:To enable distribution of a light intensity and correction thereof to be easily achieved through a simple device in a short period of time, by using a simple light distribution filter whose transmission factor changes centre-symmetically, together with a rectangular auxiliary light distribution filter which moves only toward a horizontal direction. CONSTITUTION:A glass panel 1 which is the face-plate of a picture tube is placed on the base of an exposure device. A light source 3, correcting lens 4, light distribution filter 5 and auxiliary light distribution device 6 are disposed in regular order facing the internal surface of the panel 1. This auxiliary light distribution device 6 is composed of a rectangular shading plate having its lengthwise side along the horizontal direction of the face-plate and a driving device for driving this shading plate toward the direction vertical to the face- plate, namely the direction parallel to the shorter side of the rectangular shading plate. The light distribution filter 5 is formed so that the transmission factor of light may change centre-symmetrically, namely simply in a circular form, mainly using the required light intensity distribution on the vertical axis of the pannel.

Description

DETAILED DESCRIPTION OF THE INVENTION Technical Field of the Invention The present invention relates to an exposure device for a color picture tube, and more particularly to an exposure light amount adjustment device.

TECHNICAL BACKGROUND OF THE INVENTION A conventional exposure apparatus will be described with reference to FIG. Glass panel (1
) is locked with the tuna fixed position (2 shadow mask (2) inside it. This shadow mask (2) is located at the hill, G,
Select the landing point on the inner surface of panel (1) of the 3r@ child beam emitted from the 3 electron gun corresponding to B3 color. Therefore, the purpose of the color picture tube exposure apparatus is to form a phosphor dot of a predetermined size accurately at the above-mentioned electron beam landing point. This exposure. Light #(3) is usually a high-pressure mercury lamp or the like and emits ultraviolet light of a predetermined wavelength. The correction lens (4) corrects the trajectory of the light beam emitted from the light source (3), and is a type of optical lens. That is, after the electron beam is deflected by the deflection yoke, it passes through the above-mentioned shadow mass (2) and the landing point of the light beam emitted from the light source (3) is aligned with the point where it lands inward on the panel (11). %A, 11.It is an aspherical lens represented by complex, opposite, and y.The light distribution filter (5) is formed by forming a film such as N1, Or, etc. on a glass substrate. This is to adjust the senior reaching the inner surface of the panel (1).Generally, the center of the panel (1) is closest to the light source (3), and the periphery of the panel (1) is further away, so according to the inverse square law, the senior is the closest to the light source (3). decreases.

Such an amount of light is undesirable because the surrounding phosphor dots become smaller than a predetermined buise. Therefore, in order to obtain a predetermined dot size, the light distribution filter (5) generally has a central part transmittance of 50 to 70% and a peripheral part transmittance of 80 to 100%.

Next, the process of forming phosphor dots will be explained.

The formation of phosphor dots can be divided into three steps depending on the person. The first step is to apply a slurry, which is a mixture of phosphor particles and a photosensitizer, to form a film of uniform thickness on the inner surface of the panel, and then dry it. The second step is to expose the panel for a predetermined period of time using an exposure device 62 to solidify it, and the third step is to develop the panel with the exposed layer using hot water or the like to achieve the final goal of fluorescence. This is the process of forming body dots. On the other hand, in a color picture tube having a black light absorption layer for improving contrast, it is necessary to form the black light absorption layer before the step of forming the phosphor dots. The process of forming this black light absorbing layer is carried out based on almost the same principle as the above-mentioned phosphor dot forming process, and the first process is photoresist film formation, the second process is exposure process, and the third process is development process. The fourth step is the application of a black light-absorbing material and the inversion step.

Problems with the Background Art As mentioned above, the process of forming phosphor dots and black light absorbing layer is very complicated, and the exposure light amount distribution that forms phosphor dots or black light absorbing layer of desired size is not always possible. It's not that simple either. That is, the required light amount of 1.1 cloth is determined by the above-mentioned film forming conditions, film thickness distribution development conditions, reversal conditions, etc. There is also the size of the phosphor dot or the black light absorbing layer required by the landing margin of the electron beam, and when these are taken into consideration, the transmittance distribution of the light distribution filter (5) becomes extremely complicated.

Figure 2 shows an example of the transmittance distribution of a light distribution filter.This filter has different transmittance distributions on the vertical and horizontal axes, and relatively reduces the transmitted light cover on the horizontal axis to achieve the desired phosphor dot. Or it forms a black light absorption layer. A metal vapor filter having such a transmittance distribution is not only difficult to manufacture, but also cannot be said to have good accuracy. In addition, there may be a local shortage of light from the horizontal end of the panel to the diagonal end≦2, causing phenomena such as dots to fade. Such things cause incomplete color reproduction and are a major cause of deterioration of tube yield. Such local light intensity adjustment is practically impossible with the above-mentioned gold-striped vaporization filter.

From this point of view, the same applicant as the present application previously filed a patent application filed in 1983-
9302:3, the light distribution filters with the above-mentioned complex transmittance distribution were abolished and moved in mutually perpendicular directions-1.
We have proposed a mechanical filter for exposure consisting of a pair of light-shielding plates. However, in order to adjust the light 1tX by moving the pair of light shielding plates in a binary manner, it is necessary to move the light in two directions at a non-uniform speed, which makes the design of the device extremely complicated. have.

OBJECTS OF THE INVENTION The present invention has been made in view of the above points, and provides a color picture tube exposure device that can easily obtain a light intensity distribution that is difficult or extremely complicated with ordinary light distribution filters. The purpose is to

Summary of the Invention The present invention uses a simple light distribution filter whose transmittance changes centrally symmetrically, as well as a rectangular auxiliary light distribution filter that moves only in the horizontal direction. This is a color picture tube exposure device that exposes a black light absorbing layer at a predetermined position and in a predetermined size.Examples of the Invention The present invention will be described in detail below with reference to ten examples.

FIG. 3 is a schematic diagram showing an embodiment of the present invention.

On the table of the exposure device is a color receiver gj! pipe face spray
A glass panel (1), which is a sheet of paper, is placed thereon. A shadow mask (2) having a large number of beam apertures (not shown) is fixed at a predetermined position within this panel (1). This shadow mask (2) has R, G,
3 emitted from an electron gun (not shown) corresponding to B3 color
Panel (1) of the electron beam selects the inward landing point.

A light source (3), a correction lens (4), a light distribution filter (5), and an auxiliary light distribution device (6) are arranged in this order facing the inner surface of this panel (1). And auxiliary light distribution device (6
) consists of a large-needle rectangular light-shielding plate whose longitudinal direction is horizontal to the face plate, and a drive device for driving this light-shielding plate in a direction perpendicular to the 7-ace plate, that is, in a direction parallel to the short direction of the rectangular shape. has been done. Light distribution filter (
5) is formed so that the transmittance of C light changes centrally symmetrically ff1J, ie, in a simple perfect circle shape, using the required light amount distribution mainly on the vertical axis of the panel C2. This light quantity distribution is almost the same for color picture tubes having the same deflection angle and similar screen sizes. When the light distribution filter (5) is used, the phosphor dots or the black light absorption layer may or may not have a predetermined size. In the former case, that is, when the light distribution is optimal with the above-mentioned light distribution filter (5), the auxiliary light distribution device is not necessary. Alternatively, the length of the light shielding plate (6 m) in the short direction (hereinafter referred to as width) may be made into a uniform strip shape as shown in FIG.

However, the cases in which a predetermined phosphor dot or black light absorption layer is usually formed by the above-mentioned light distribution filter (5)C2 are very rare, and as mentioned above, there are cases in which it is necessary to reduce the amount of light toward the horizontal end. The reality is that it is necessary to locally increase the amount of light from the horizontal end to the diagonal end.

Figure 5 shows the shape of the light-shielding plate (6b) suitable for reducing the amount of light toward the horizontal edge of the panel.The width of the light-shielding plate is different between the central part and the outside of the central part.In this case, the width of the central part is different. It is formed to be the smallest. Figure 6 shows the shape of the light shielding plate (6c) suitable for locally increasing the amount of light from the horizontal end of the panel to the diagonal end. is said to have a bulging shape in the center.

The light-shielding plate shown in Figures 4 to 6 can be moved at least -1 times in the direction of the panel vertical axis within the exposure time, but the width of the light-shielding plate can be changed in advance according to the panel ζ2 to be exposed. For example, movement can be done at a constant speed.

Furthermore, by using a pulse motor to drive the light shielding plate, the travel time of the light shielding plate can be accurately controlled.

The exposure time on the panel is relatively short in areas where the width of the light shielding plate is large, and conversely, the exposure time is relatively long in areas where the width is small. As this integrated light amount distribution, a desired distribution different from the light amount distribution by the light distribution filter is obtained.

As described above, by using the auxiliary light distribution device according to the present invention, it is possible to easily achieve the desired light amount distribution with a simple device without using a conventional complicated light distribution filter. The distribution can be modified very quickly (C): it can be carried out in a short time, and the optimum light amount distribution can be obtained in accordance with the film formation, development requirements, etc. In addition, the light distribution filter can be limited to those having basic light distribution, and by reducing the number of types of filters, it is possible to reduce the cost of the filter. Furthermore, if the light-shielding plate according to the present invention is manufactured using Kinmeteitahiro, it can be used almost semi-permanently, and its industrial value is extremely high (
Two big.

Similarly, the light distribution filter may be one having a perfectly circular transmittance distribution (although it is not limited to two), and even if it is used as a light distribution filter having a perfectly circular transmittance distribution, the present invention is applicable to the same implementation. Needless to say, it's rice.

[Brief explanation of the drawing]

FIG. 1 is a schematic diagram showing a conventional exposure apparatus, FIG. 2 is a schematic diagram showing a transmittance distribution of a light distribution filter, FIG. 3 is a schematic diagram showing an embodiment of the exposure apparatus of the present invention, and FIG. 6 through 6 are schematic plan views showing the light shielding plate of the auxiliary light distribution device. (1)...Panel (2+...Shadow mask (3)...Light source (4)...Correction lens (5)...Light distribution filter (6)...Auxiliary light distribution device ( 6a), (6b), (6(ri・! Light board No. 4
Figure 5 Figure 6

Claims (2)

[Claims] (1) In a color picture tube exposure device that exposes and forms a phosphor or a black light absorption wIi through the shadow mask at a predetermined position of a face plate to which a shadow mask is fixed, the exposure device includes at least a light source. , a light beam trajectory correction lens, a light distribution filter for adjusting the amount of light, and an auxiliary light distribution device that is engraved on the light distribution filter and auxiliary adjusts the amount of light, and this auxiliary light distribution device is arranged in the horizontal direction of the face plate. A color picture tube exposure device 0 characterized in that it comprises a generally rectangular light-shielding plate having a longitudinal direction and a driving device for driving the light-shielding plate in a direction perpendicular to the face plate. (2) The color picture tube exposure apparatus according to claim 1, wherein the width of the rectangular light shielding plate in the transverse direction is different between a central portion and a portion outside the central portion.