JPH03149730A - Phosphor pattern forming method for color cathode-ray tube and exposing device - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a method for forming a phosphor pattern for a color cathode ray tube and an exposure apparatus.

[Conventional technology]

The phosphor screen of a color cathode ray tube has striped or dot-shaped phosphors that emit light in each of the three primary colors of light, red, green, and blue, arranged on the inner surface of the glass panel, and the gaps between the phosphors are It has a structure filled with a Blafuku matrix made of light-absorbing horse body material.

Conventionally, this type of phosphor screen has been formed using the exposure apparatus disclosed in Japanese Patent Application Laid-Open No. 60-9030, as shown in FIG. 7, through the steps shown in FIGS. It had been. In FIG. 7, l is a glass panel, 6 is a shadow mask, 6a is an opening, 7 is a housing, 8 is a plate, and 9
is a light source, lO is a correction lens, 11 is a filter, 21 is a center line of the correction lens lO, and 22 is a center line of the light source 9.

Next, a method of forming a phosphor pattern for a color cathode ray tube will be explained using FIG. First, as shown in FIG. 8(a), a black matrix 2 is formed on the inner surface of the glass panel 1 by a known method, and then, as shown in FIG. A slurry 5a made of photosensitive resin 4 containing one phosphor 3 is applied and dried. Thereafter, as shown in FIG. 8 (6), a shadow mask 6 is attached to the glass panel L, and as shown in FIG. A light source 9, which is a high-pressure mercury lamp, is installed at a position corresponding to the center to perform exposure.

At this time, a correction lens lO is installed in front of the light source 9 in order to make the optical path of the light emitted from the light source 9 match or approximate the trajectory of the electron beam for producing an image after being assembled as a color cathode ray tube. is set up. Further, the light emitted from the light source 9 passes through a filter 11 that adjusts the amount of light, and is irradiated onto the shadow mask 6, thereby exposing the slurry 5a located in the opening 6a. Next, the shadow mask 6 is removed, the glass panel l is moved to a developing device, and the non-exposed areas are removed by hot water spray, so that only the exposed areas are covered with a phosphor pattern, as shown in FIG. 8 (6). is formed as.

After forming the 111W4 phosphor pattern in the above manner, as shown in FIG. 8(e), a slurry 5b containing another type of phosphor is applied, and as shown in FIG.
Another type of phosphor pattern is formed through the exposure step shown in f) and the development step shown in FIG. 8(6). Furthermore, the eighth
As shown in Figure (c), a slurry 50 containing the remaining lli type phosphor is applied, and the final step is carried out through the exposure process shown in Figure 8 (f) and the development process shown in Figure 8 (i) in the same manner as above. 11
The phosphor screen forming process is completed by forming a type 1 phosphor pattern.

The cross-sectional structure of the glass panel provided with a phosphor screen produced by the conventional method described above is shown in FIG. 9, and the surface structure of the phosphor screen is shown in FIG. G indicates green, that is, the second phosphor pattern, and B indicates blue, that is, the third phosphor pattern.

[Problem to be solved by the invention]

The phosphor patterns of conventional color cathode ray tubes are formed by the above method, but there are the following problems.

It is necessary to attach and detach the shadow mask to the glass panel each time a phosphor of 111111 is formed, and this complexity not only obstructs production rationalization, but also causes errors in the placement position of the shadow mask and errors in the shadow mask opening. The diffraction phenomenon of light causes fogging of adjacent phosphor patterns, and the projection of dust on the shadow mask causes defective patterns, which adversely affects the sharpness of color cathode ray tubes. In addition, since the relative relationship between the shadow mask and the electron beam trajectory differs depending on the type of cathode ray tube, a correction lens corresponding to the type of cathode ray tube is required, which not only increases the cost of the cathode ray tube, but also adheres to the correction lens. The dust was projected and formed a defective pattern, which had a negative effect on the sharpness of the color cathode ray tube. Furthermore, each time the pipe type is changed, it is necessary to replace and adjust the correction lens.
This severely hindered the ability to respond to the trend in production methods, which is the shift to high-mix, low-volume production.

This invention was made to solve the above-mentioned problems.
However, it is also an object of the present invention to provide a method and exposure apparatus for forming a phosphor pattern for a color cathode ray tube, which has clear fluorescence characteristics and enables mixed production of various cathode ray tubes, even without using a correction lens.

[Means to solve the problem]

The method for forming a phosphor pattern in a color cathode ray tube according to the invention measures the position of the black matrix by detecting the amount of fluorescence generated from the phosphor excited by the electron beam during electron beam irradiation, This is to correct the electron beam irradiation position.

Further, the phosphor pattern exposure apparatus for a color cathode ray tube according to the present invention includes means for irradiating a weak-intensity electron beam to a predetermined position based on design data of the phosphor pattern;
means for measuring the amount of light generated from the phosphor by irradiation with the electron beam; and a means for measuring the amount of light generated from the phosphor by irradiation with the electron beam; and means for irradiating the phosphor with a beam to expose the phosphor.

[Effect]

In this invention, the irradiation position of the electron beam is controlled by detecting the position of the black matrix by utilizing the fact that the amount of fluorescence generated from the phosphor excited by the electron beam is extremely different depending on the presence or absence of the black matrix. However, the phosphor pattern can be directly exposed without using a shadow mask or correction lens.

Furthermore, in this invention, prior to exposing the phosphor pattern, the electron beam irradiation position is corrected using a low-intensity electron beam, so there is no risk of exposing unnecessary parts of the phosphor during the correction operation. It disappears.

〔Example〕

Hereinafter, embodiments of the present invention will be described with reference to the drawings.

FIG. 1 shows an apparatus for performing exposure using a method for forming a phosphor pattern of a color cathode ray tube according to an embodiment of the present invention. 17 is a deflection power source for the electron beam, 18 is a photomultiplier, photodiode, television camera, etc., and measures the fluorescence generated from the phosphor. detector for,
19 is a measurement circuit, and 20 is a correction circuit for correcting an irradiation position error.

Further, FIG. 2 is an explanatory diagram illustrating a method of determining the irradiation position l error from the detection signal of the detector 18.

Next, a specific method for forming a phosphor pattern will be explained with reference to the drawings. First, a glass panel I coated with a slurry 5 to be exposed is positioned with high precision, and an electron beam 15 is generated. The positioning of the electron beam 15 is controlled by a control device 16 based on design data given in advance according to the color of the phosphor 3 contained in the slurry 5 to be exposed. The irradiation position of the electron beam 15 is controlled by the electron beam deflection power source 1.
This is done using the current value generated from 7 and applied to the deflection coil.
The electron beam 15 scans as shown in FIG. 2(a), for example, depending on the position where the slurry 5 is applied. As shown by the arrow in FIG. 2(a), the scanning signal of the electron beam 15 is
It is created from design data so as to scan the center of the black matrix 2, that is, the middle of the black matrix 2, and is given as the current value of the electron beam deflection coil. When the slurry 5 is irradiated with the electron beam 15, fluorescence corresponding to the amount blocked by the black matrix 2 is generated from the area of the phosphor 3 in the slurry 5 that is hit by the electron beam 15, and is absorbed by the electron beam. The light is received by a fluorescent device 18 installed on the opposite side of the light source 15. This fluorescence changes as shown in FIG. 2(b) depending on the position of the electron beam 15. Figure 2 (c) shows the changes in the transmitted fluorescence when the electron beam 15M is located at the center of the black matrix 2, as shown by the solid line in Figure 2 (a), and when the electron beam 15M is located at the center of the black matrix 2, as shown by the broken line in Figure 2 (a). The amount of transmitted fluorescence when the electron beam 15L is shifted to the left is indicated by BM and BL, respectively. This change in fluorescence is detected by a fluorescence detector 18,
The position of the electron beam 15 is controlled in a direction in which the fluorescence increases as it decreases.

FIG. 3 shows an embodiment of the measurement circuit 19 that processes changes in the amount of light from the fluorescence detector 18. In the figure, 21 is an amplifier, 22A and 22B are sample and hold circuits, 23 is a subtracter, and 24 is a timing generator. A timing generating circuit 24 generates a pulse with timing for sampling and holding. This pulse is timed to control the position of the electron beam 15.

Next, the operation of the measurement circuit in FIG. 3 will be explained with reference to FIG. 4. (a) is the output from the fluorescence detector, (b) is the timing pulse of sample hold circuit A, and (b) is sample hold circuit B. The timing pulse is the output of the sample-and-hold circuit A, (→ is the output of the sample-and-hold circuit B, and (f) is the output of the subtracter.

As shown in FIGS. 4(C) and 4(C), the sample hold circuit A 22A and the sample hold circuit 822B hold the outputs of the fluorescence detector 18 at different timings.

By finding the difference between these two outputs using the subtracter 23,
The direction and amount of deviation of the electron beam 15 are measured. In this case, the direction of deviation can only be determined as being toward the center or toward the periphery, as shown in Figure 2 (
Although it is not possible to know which side of the output curve (c) is on the other side, the control device! By intentionally shifting the position of the electron beam at f16, the direction of the shift can be measured. In this way, a correction signal for the position of the electron beam 150 can be obtained from the output from the fluorescence detector 18, and highly accurate exposure can be performed along the black matrix 2 via the correction circuit 20.

In the above embodiment, as shown in FIG. 2(a), the case where the electron beam 15 with a large spot diameter is linearly scanned along the black matrix 2 was explained.
As shown in Fig. 5, the electron beam 1 with a small spot diameter
It goes without saying that the same effect as in the above embodiment can be obtained even if the present invention is applied to the case of scanning waveform.

Next, an embodiment of the second invention will be explained using FIG. 1, which is the same as that used to explain the first invention, and FIG. 6
This will be explained based on the diagram. In FIG. 6, 5 is a slurry containing a phosphor, 25 is an exposed area of a phosphor-exposed body, and 26 is a slurry containing a phosphor.
is the designed irradiation area of the electron beam 15, and 27 is the corrected irradiation area of the electron beam 15.

Next, the operation will be explained. After accurately positioning the glass panel 1 coated with the slurry 5, an electron beam 15 is irradiated onto a designed irradiation area 26 that is determined in advance from design data according to the color of the phosphor contained in the slurry 5. The light is received by a fluorescence detector 18 installed on the opposite side of the electron beam 15. At this time, since the exposure area 25 of the phosphor corresponds to the dot-shaped hole of the black matrix, only the light emitted from the phosphor existing in the overlapping part of the irradiation area 26 and the exposure area 25 of the phosphor is detected by the fluorescence detector. Detected on 18th. Next, the apparatus shown in FIG. 1 is operated to scan the electron beam 15 back and forth and left and right. Here, the intensity of the electron beam 15 that irradiates the slurry 5 is weak enough to not expose the slurry 5 in a short time, so there is no need to worry about exposing unnecessary parts of the slurry 5 during the above operation.Fluorescence detection The position of the electron beam 15 is controlled in a direction in which the amount of fluorescence detected by the device 1B increases as it decreases, the corrected irradiation area 27 is found, and the intensity of the electron beam 15 is increased to complete the exposure of the phosphor in a short time. .

This operation is repeated to draw all the phosphors of one color, and the drawing of the phosphors of this color is completed. Next, on the glass panel l on which drawing has been completed, the slurry 5 in the portions not irradiated with the electron beam 15 is removed by development, and the exposure of the phosphor of that color is completed. From the above application of slurry 5,
A series of steps up to drawing and development using the electron beam 15 are performed on the remaining two color phosphors to complete the three color phosphor Φ exposure.

【Effect of the invention〕

As described above, according to these inventions, the position of the black matrix is measured by detecting the amount of fluorescence generated from the phosphor that absorbs the electron beam during electron beam irradiation, and the position of the black matrix is determined according to this position. Since the irradiation position is corrected, direct exposure can be performed with high precision without using a shadow mask or correction lens when forming a phosphor pattern.
Not only can it eliminate quality problems such as the occurrence of defective patterns, but it can also suppress the increase in production costs caused by the use of correction lenses.Furthermore, as a result of reducing replacement work and adjustment work, it is possible to produce a wide variety of products in small quantities. This has the great effect of making the transition easier.

Furthermore, since an electron beam of low intensity is used to correct the electron beam irradiation position, there is an effect that the risk of exposing unnecessary portions of the phosphor during the above correction operation can be eliminated.

[Brief explanation of the drawing]

FIG. 1 is a block diagram of an exposure apparatus for explaining a method of forming a phosphor pattern for a color cathode ray tube according to an embodiment of the first and second aspects of the present invention, and FIGS. 2(a) and (b) are respectively Explanatory diagram showing the electron beam irradiation position and the output of the fluorescence detector at each irradiation position in the first invention, the third invention
The figure is a circuit diagram showing one embodiment of the measuring circuit of Fig. 1, Figs. 4(a) to 4(f) are timing chart diagrams each explaining the operation of the measuring circuit, and Fig. 5 is a circuit diagram showing an embodiment of the measuring circuit of Fig. 1. FIG. 6 is an explanatory diagram showing the electron beam scanning method according to the second embodiment of the present invention, FIG. 6 is an explanatory diagram showing the irradiation position of the electron beam in the second invention of the present invention, and FIG. 7 is a diagram showing a conventional color cathode ray tube exposure device. The cross-sectional view, Fig. 8 (a) to U) shows the conventional collar.
- A cross-sectional view showing the method for forming a phosphor pattern on a cathode ray tube in the order of steps; Figure 9 is a cross-sectional view showing the structure of a glass panel with a phosphor screen made by a conventional method; Figure 1θ is a front view showing the surface structure of the phosphor screen. It is. In the figure, 1 is a glass panel, 2 is a black matrix, 3 is a phosphor, 4 is a photosensitive resin, 15 is an electron beam, and 18 is a fluorescence detector. Note that the same reference numerals in each figure indicate the same or corresponding parts.

Claims (2)

[Claims] (1) In a method of forming a pattern on a phosphor by irradiating and exposing a phosphor to a predetermined position on a phosphor coated with a photosensitive resin on a color cathode ray tube panel in which a plurality of black matrices are arranged, the above-mentioned electron beam is applied. A color characterized in that the position of the black matrix is measured by detecting the amount of fluorescence generated from the phosphor excited by the electron beam during irradiation, and the electron beam irradiation position is corrected according to this position. Method for forming phosphor patterns on cathode ray tubes. (2) In a device that forms a pattern on the phosphor by irradiating and exposing the phosphor to a predetermined position on the phosphor coated with a photosensitive resin on a color cathode ray tube panel in which a plurality of black matrices are arranged, by irradiating and exposing the phosphor to a predetermined pattern. means for irradiating a weakly intense electron beam to a predetermined position based on design data of the pattern of phosphor coated on the inside of a panel of a color cathode ray tube having a black matrix; a means for measuring the amount of light emitted from the body; and a means for measuring the amount of light emitted from the body, and irradiating the electron beam with a stronger intensity than the electron beam to the position where the amount of light determined from the measured value of the amount of light is the maximum, thereby irradiating the phosphor with an electron beam having a stronger intensity than the electron beam. 1. A phosphor pattern exposure device for a color cathode ray tube, comprising: means for exposing.