JPH0218836A - Fluorescent screen forming device for color cathode-ray tube - Google Patents

Abstract

PURPOSE:To form a fluorescent film with excellent landing characteristic by inserting a correcting lens with a single continuous curved surface and a composite correcting lens with a composite curved surface between a face panel and an exposing device. CONSTITUTION:The light emitted from the light source 4 of an exposing device 3 is first refracted by the preset quantity by a correcting lens 11 with a single continuous curved surface. It is further refracted by the preset quantity by a composite correcting lens 12 with a composite curved surface located above, it is then exposed on the photosensitive film 9 of a face panel 8 through the mask hole of a shadow mask 10 to form a preset fluorescent screen pattern. The composite correcting lens with little step difference between multiple areas can be used due to the existence of another correcting lens. The adverse effect of the step difference on the photosensitive film is reduced, also the step difference is reduced, thereby the reduction of landing characteristic due to the composite correcting lens can be suppressed.

Description

[Detailed Description of the Invention] [Field of Industrial Application] The present invention relates to a phosphor screen forming device that creates a three-color phosphor screen pattern on the inner surface of the face panel of a color cathode ray tube. The present invention relates to a phosphor screen manufacturing device that improves the landing characteristics of a shaped phosphor screen.

[Prior Art] Fig. 6(A) is an 11-dimensional diagram of a conventional color cathode ray tube phosphor screen forming apparatus disclosed in Japanese Patent Publication No. 18572/1982, without showing the main parts in cross section. .

In the same figure, (11 is a support frame, and a plurality of support stands (2a), (2b
) and (2c) are provided. (3) is the light source (4
) and a condensing lens (5), this exposure device (3) uses the most advanced light beam (6) to create trajectories of light rays (6) corresponding to the respective colors of the three-color phosphor. It is adjustably attached to the support stand (2a).

(7) is a compound correction lens for wide deflection angles attached to the support base (2b) of the support frame (1), as shown in Figure 6(7).
As shown previously, multiple regions (7a) parallel to each other,
It is divided into (7b) and (7c). Each area (7a), (7b) of this compound correction lens (7)
) and (7c) are each formed by a single continuous curved surface, and these are connected as a whole to form a composite curved surface, and the boundaries TA) and (Bl of each area have a sixth
As shown in Figure (A), a step is formed. Further, this compound correction lens (7) is controlled by a vibration generator (not shown) attached to the support base (2b).

The amplitude l~ in the direction orthogonal to the above boundary (Δl, (11))
It is configured so that vibrations of about 5 mm are applied at a rate of about 10 times/minute.

(8) is a face panel of a color cathode ray tube, and this face panel (8) is attached to the substantially central portion of the support base (2c) with its inner surface facing downward. (9) is a photosensitive film formed on the inner surface of the face panel, which is made by applying a slurry of a photosensitive resin with a phosphor dispersed therein and drying it. (lO) is a shadow mask, which is detachably attached to the face panel (8) at a predetermined distance from the photosensitive film (9).

Next, an example of the use of the exposure apparatus having the above configuration is shown in FIG. 6(A).
I will explain based on this.

When creating a three-color mosaic phosphor screen on the inner surface of the face panel (8), first apply a photoresist film (9) of only one of the three color phosphors to the inner surface of the face panel (8). Apply the shadow mask (
10) Install.

Next, the light beam (6) emitted from the light source (4) of the exposure device (3), which has been moved to a position matching the trajectory of the light beam (6) corresponding to that color, is transmitted to a vibration generator (not shown). The face panel (8) passes through the compound correction lens (7), which is vibrated by the
) The entire surface of the photoresist film (9) is exposed to light in a dotted manner and developed to form a first color phosphor screen pattern. In addition, the other 2
When exposing a color, the shadow mask (lO) is removed, the exposure device (3) is adjusted to a position that matches the trajectory of the light beam corresponding to that color, and then the process described in 1. is repeated.

[Problems to be Solved by the Invention] As described above, the wide deflection angle compound correction lens (7) in the conventional color cathode ray tube phosphor screen forming device has a plurality of regions [7a] divided parallel to each other. , (7b) and (7c) are each formed by a single continuous curved surface, and these are connected as a whole to form a compound curved surface, and during the manufacturing of the phosphor screen, this compound correction lens (7) is used for each area. Relatively large vibrations are applied in the direction orthogonal to the boundaries (^) and (B), and the steps formed at the boundaries of the above areas have an adverse effect on the photoresist film (9) (the photoresist film is opaque so that no light hits it). This is to prevent the film image from being projected, resulting in areas where there is no phosphor.

However, even if the compound correction lens (7) formed with a compound surface as described above improves the landing characteristics of the important surface, it is difficult to vibrate the compound correction lens (7) during the manufacture of the phosphor screen. is the above compound correction lens (7)
However, there is a problem in that the landing characteristics that have been achieved with great effort are significantly degraded.

This invention was made in order to improve the above-mentioned problems, and includes a compound correction lens in which a plurality of regions divided parallel to each other are each formed by a single continuous curved surface, and these are connected to form a compound curved surface. , to provide a phosphor screen forming device in which a correction lens having a single asymmetrical continuous curved surface is interposed between a face panel and an exposure device to form a phosphor film having excellent landing characteristics. target

[Means for Solving the Problems] A phosphor screen forming apparatus for a color cathode ray tube according to the present invention includes a correction lens having a single continuous curved surface and a correction lens having a single continuous curved surface between a face panel on which a photosensitive film is formed and an exposure device containing a built-in light source. A plurality of regions divided parallel to each other are each formed by a single continuous curved surface, and a compound correction lens having a compound curved surface connecting these regions is interposed.

[Function] According to the present invention, the complementary IE lens having a single continuous curved surface and the compound correction lens having a compound curved surface are interposed between the face panel and the exposure device. It becomes possible to use a compound correction lens with a small difference in level between a plurality of regions. Therefore, not only the adverse effect of the step on the photoresist film is reduced, but also the amplitude of the compound correction lens can be reduced due to the reduction in the step, and it is possible to suppress the deterioration of the landing characteristic due to the compound correction lens.

[Embodiment] FIG. 1 is a plan view showing a phosphor screen forming apparatus for a color cathode ray tube according to an embodiment of the present invention, with main parts taken in cross section. The same reference numerals are given to the same or equivalent parts as in the above, and detailed explanation thereof will be omitted.

In the same figure, (1) is a correction lens for light deflection having a single continuous curved surface with a complex curved surface, which aligns the trajectory of the light ray (6) emitted from the light source (5) with the optical path during exposure. In order to correct the deviation of the deflection center due to the deflection angle, the support base (2d) is adjustable.

(12) is a compound correction lens for wide deflection angle attached to the support base (2b) on the upper part of the correction lens (11), and as shown in the front view of FIG. A plurality of parallel regions 112a), (12b),
(12c) and (12dl) Each area (12a) of this compound correction lens (I2)
, (12b), (12c) and +12dl are each formed as a single continuous curved surface, and these are connected as a whole to form a composite curved surface, and the boundary surface of each region (Al, (111 and (C)) is As shown in Fig. 1, a step is formed.In addition, this compound correction lens (12) is connected to a drive device (
(not shown) to reciprocate on the support base (2b) at a predetermined stroke and speed.

Next, the operation of the configuration described in item 1 will be explained.

Now, the light beam (6) emitted from the light source (4) of the exposure device (3) first passes through the correction lens (1) that
1), and is further refracted by a predetermined amount by a compound correction lens (12) having a compound curved surface located above this, and then passes through the mask hole of the shadow mask (10) to the exposed light of the face panel (8). The film (9) is exposed to light to form a predetermined phosphor screen pattern.

Next, the procedure for selecting the correction lens (fl) having a single continuous curved surface and the compound correction lens (12) having a compound curved surface used in the phosphor screen producing apparatus according to the present invention will be explained.

First, a deflection yoke is attached to a prototype color cathode ray tube made using only a single trial correction lens with a single continuous curved surface, which is either selected at random or created at random, and the landing characteristics are uniformly applied to the entire screen. Measure as many times as necessary.

Based on the data on the landing characteristics obtained in this way, we begin designing a correction lens that will be actually used so as to have the best landing characteristics. Moreover, the compound correction lens described in −1-7 has a predetermined thickness! Only the 111 continuous curved lens in the 1t-region will be designed. According to experiments, it is possible to proceed with the design work using only this single continuous curved lens until the landing deviation is 15 μm or less.

Next, the division of the compound correction lens (I2) described in I is, for example! 11. If the landing deviation (S) that cannot be corrected by the continuous bending lens alone is as shown in the screen of the face panel (8) shown in Fig. 3 (A), The area is divided into two regions (12a) and (12b) and these are given as initial values.

Next, the landing deviation due to each single continuous curved surface of each of the plurality of regions divided into f rows (remaining supplementary 11 mm) is the pattern deviation ( S). In FIG. 4, the X-axis coincides with the direction in which the electron beam is deflected by the deflection coil of the deflection coil, and the Y-axis, which is orthogonal to the X-axis, corresponds to the joint plane deflection coil of the deflection coil. This corresponds to the direction in which the electron beam is deflected. ” - In the case of pattern deviation as shown in Fig. 4, Fig. 5 (Al, (1
As shown in 1), the boundary surface (
The initial value of the number of divisions is given by assuming a curved surface that has Al, (B) and (C) and is continuous in the direction perpendicular thereto.

Next, in this compound correction lens (I2), in order to determine the surface shape of each boundary surface (A), (B), and (C), each divided region (12a), (12bl, (1
2c) and +12dl are individually designed to correct the landing deviations corresponding to +12dl. The combination of the composite correction lens designed in this manner and a single continuous curved surface can ensure that the remaining amount of correction for deviations in landing characteristics is zero. This is because when the landing deviation to be corrected is divided into individual lenses, the deviation does not form a closed curve. In other words, this is because the dividing means of the composite correction lens is designed to prevent the deviation of the landing characteristics from becoming a closed curve.

Next, the problem with the composite correction lens made as described above is the step formed at each region boundary surface (^), (B), and (C). The remaining correction by the +11 continuous curved lens is about 15 μm at most, so this series of design work! By the second attempt, in most cases 0.1m
The height difference can be approximately m. Therefore, in many cases, the design of a compound correction lens will yield almost satisfactory results on the first trial, but if you want to further reduce the step difference, you can do so by increasing the number of divided regions. In the case of a lens having a boundary surface only in the X-axis direction, the compound correction lens may be redesigned without changing the dividing method.

However, if you are not satisfied with this result, please make slight adjustments to the coefficients of the formula that expresses the curved surface of the compound correction lens obtained as a result of the step 2 to further reduce the step difference. So, next is this minor correction i [compound correction lens 1
j'', 11 designs of a single continuous curved lens may be performed.

As described above, the compound correction lens having a compound curved surface and the
11 The design of a correction lens having a continuous curved surface is completed by repeating a cross-over process in which one lens is a fine correction lens and the other is designed.

In the above embodiment, a case was described in which one correction lens (11) having a single continuous curved surface was placed on the exposure device (3) side, but the compound correction lens (12) having a compound curved surface was placed on the exposure device side. It goes without saying that even if it is placed on the (3) side, similar effects can be achieved.

[Effects of the Invention] According to the present invention, since the correction lens having a single continuous curved surface and the compound correction lens having a compound curved surface are interposed between the face panel and the exposure device, the presence of one correction lens is unnecessary. This makes it possible to use a compound correction lens with small differences in level between multiple regions. Therefore, not only is the negative effect of the level difference on the photoresist film reduced, but also the amplitude of the compound correction lens can be reduced by reducing the level difference, and it is possible to suppress the deterioration of the landing characteristics due to the compound correction lens and also make it possible to reduce the amplitude of the compound correction lens. Since the amplitude of the correction lens is reduced, costs can be reduced by downsizing the drive source.

[Brief explanation of drawings]

FIG. 1 is a front view showing a phosphor screen forming apparatus for a color cathode ray tube according to an embodiment of the present invention with main parts cut away, FIG. 2 is a front view of a compound correction lens for forming a compound curved surface, and FIG. A
) is a front view of the face panel showing landing deviation,
Fig. 3 (81 is a perspective view of the compound correction lens used for the correction, Fig. 4 (A) and Fig. 4 (B) are front views of the face panel showing other landing deviations, Fig. 5 (A) and FIG. 5(B) is a perspective view of a compound correction lens used for the correction, FIG. 6(A) is a front view showing the main part of a conventional color cathode ray tube phosphor screen forming device in cross section, and FIG. Bl
is a front view of a compound correction lens having a compound curved surface. (3)...Exposure device, (4)...Light source, (8)...
・Face panel, (9)...Photoresist film, (1ri...
Complementary IE lens, (+2) - Composite correction lens, (12
al , (12b) , (+2c) and (12d
) −...area. In addition, in FIG. 1, the same reference numerals indicate the same or corresponding parts.

Claims (1)

[Claims] (1) Between the face panel on which the photoresist film is formed and the exposure device with a built-in light source, there is a riding misalignment correction lens with a single continuous curved surface, and a plurality of areas divided parallel to each other, each with a single continuous curved surface. A phosphor screen production device for a color cathode ray tube, which is formed by interposing a riding deviation compound correction lens having a compound curved surface formed by connecting these surfaces.