JPS6315695B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for forming a black matrix in a black matrix tube and for exposing a phosphor surface of a color picture tube to form a phosphor surface.

Generally, the fluorescent surface and black matrix surface of a shadow mask type color picture tube are formed by photography, but an exposure device commonly called a light house as shown in Figure 1 is used for exposure. There is. This exposure apparatus includes a light house main body 1, a light source section 2, a light beam correction lens 4 supported by a lens frame 3, and a light amount correction filter 5. The lens frame 3 is fixed to a frame 7 by a pin 6. Then, a panel 10 with a shadow mask 9 attached thereto is positioned and mounted on a plate 8 fixed to the upper end of the light house main body 1, and a shutter 11 is opened to perform exposure.

A photosensitive slurry and a photoresist are applied to the inner surface of the panel 10 in the exposure apparatus configured as described above, and the shadow mask 9 is attached.
The slits and dots formed in the photosensitive slurry are exposed to light on a photoresist, developed by an appropriate method, and dried to form a fluorescent surface.

The shadow mask 9 of the striped type color picture tube has slits 12 (12
a, 12b) shaped openings and a light shielding portion of the bridge portion 13 are formed. However, in order to improve the irradiation margin of the electron beam, the phosphor surface is formed by forming a black matrix and phosphor stripes with a uniform width that eliminates the influence of the bridge portion. For this reason, as the light source section 2, a linear light source 14 made of a mercury lamp is attached to an aperture block 15 as shown in FIG. 3.
As shown in FIG. 4, the exposure method is to perform exposure using a linear light source 14 arranged perpendicular to the long side of the panel 10 and parallel to the long axis direction of the slit 12, thereby forming a fluorescent surface. The light spot generated becomes larger in the long axis direction of the slit, and the projection of the bridge part 13 is erased by the overlap with the light spots 16a, 16b formed from the adjacent slit parts 12a, 12b, forming a stripe shape of uniform width. is forming. The length of the linear light source 14 is determined by the aperture block 1 shown in FIG.
This is done through the opening of No.5.

In addition, during exposure, in order to improve the quality of the color picture tube, a stripe width is made smaller than the width of the slit 12 formed in the shadow mask 9, and a large electron beam is irradiated to improve the beam irradiation latitude. . This state is as shown in FIGS. 5 and 6 in the central and peripheral parts of the panel 10. In FIG. 5, A is the phosphor stripe width, B is the electron beam width, C is the shadow mask slit width, and D is the black matrix stripe width. That is, since the beam irradiation latitude decreases toward the periphery of the panel, the stripe width 17 is formed smaller than the width of the slit 12 of the shadow mask 9 (the black matrix width becomes larger). In order to form the above-mentioned black matrix width, in the exposure device,
A light amount correction filter 5 is manufactured so that the amount of light during exposure at the periphery of the panel 10 is smaller than that at the center. In addition, regarding the formation of the phosphor stripe width, we take into account adhesive strength, mixing with other colors, and chipping margin (displacement of the phosphor stripe position relative to the black stripe position), and the slits formed in the shadow mask 9 are A large phosphor stripe 18 is formed at the same ratio in both the central and peripheral parts of the panel 10 with respect to the width of the panel 12. For this reason, the light amount correction filter 5 is manufactured and exposed so that the amount of light is the same at the center and the periphery of the panel.

When a fluorescent surface is formed by the above method, the effective surface 19 of the black matrix on the long side of the panel 10 is wide at the center of the long side and narrow at the periphery, as shown in FIG. A problem resulting in distortion (solid line part) occurs. Furthermore, since the effective surface 20 of the phosphor stripe 18 is equal in both the center and the periphery, the remainder of the phosphor stripe width relative to the effective surface 19 of the black matrix 17 is larger in the periphery than in the center ( (dotted line). When this is irradiated with an electron beam, the light emitting state of the phosphor stripes differs between the central part and the peripheral part on the long side of the panel, resulting in abnormal unevenness (abnormal light emission) on the phosphor surface, which deteriorates the image quality.

The present invention has been made in view of the above-mentioned drawbacks of the prior art, and it is an object of the present invention to provide a method for exposing the phosphor surface of a color picture tube, which can prevent abnormal light emission from the phosphor surface.

In order to achieve the above object, the present invention changes the length of a linear light source of an exposure device when exposing a photoresist and when exposing a phosphor, and further changes the length of the light source between the center and the periphery of the panel for exposure. It is characterized by the following.

Hereinafter, the method of the present invention will be explained with reference to an illustrated embodiment. FIG. 7 shows an aperture block used in the method of the present invention for defining the length of the light source, in which a shows an aperture block for exposing a photoresist, and b shows an aperture block for exposing a phosphor slurry. As shown in the figure, linear light sources 23 made of mercury lamps are attached to aperture blocks 21 and 22 for photoresist exposure and phosphor slurry exposure, respectively. The aperture block 21 for photoresist exposure has a portion of the linear light source 23 with a narrow width.
The opening 21 becomes wider as it goes further away.
a is formed. Conversely, the aperture block 22 for exposing the phosphor slurry has a linear light source 2.
An opening 22a is formed which is wide at a portion 3 and becomes narrower toward a portion farther from the linear light source 23.

Aperture block 2 formed in this way
1 and 22 are set in the exposure main body 24 of the exposure section as shown in FIG. and the upper part thereof is fixed with a fixing plate 27.

In this way, the center and peripheral parts of the panel 10 have aperture blocks 2 that define the length of the light source.
The positions of the openings 21a and 22a of Nos. 1 and 22 are different. Therefore, the aperture block 2 as described above
1 and 22 to form a phosphorescent surface, when forming a black matrix, the length of the light source exposed to light becomes short in the central part on the long side of the panel, and becomes long in the peripheral part. Therefore, the distortion on the effective surface can be corrected. Furthermore, when exposing the phosphor stripes, the light source length is opposite to that of the black matrix, so the light source length is long at the center on the long side of the panel and short at the periphery. As a result, the effective surface of the phosphor becomes equivalent to that of a black matrix, so abnormal light emission due to electron beam irradiation is prevented, and a high-quality phosphor surface can be formed.

In the above embodiment, the length of the light source was changed at the same time when forming the black matrix and when forming the phosphor stripes. also has that effect. Further, although the length of the light source is changed by the aperture blocks 21 and 22, it is also possible to obtain the same effect by disposing a light shielding plate above the light source section.

As is clear from the above description, according to the method of exposing the fluorescent surface of a color picture tube according to the present invention, a high quality fluorescent surface free from abnormal light emission can be obtained.

[Brief explanation of the drawing]

Fig. 1 is a cross-sectional view of a conventional exposure device, Fig. 2 is a schematic diagram of a stripe type shadow mask, Fig. 3 is a perspective view of a conventional aperture block, and Fig. 4 is an erased portion of the shadow mask bridge. An explanatory diagram of the method; FIG. 5 is a diagram of the relationship between black stripe width, phosphor stripe width, and electron beam width; FIG. 6 is an explanatory diagram of problems caused by conventional exposure; and FIGS. FIG. 8 is a perspective view of an aperture block for determining the length of a light source used in the method of FIG. 21, 22...Aperture block, 21
a, 22a...opening, 23...linear light source.

Claims (1)

[Claims] 1 In an exposure method in which a photosensitive slurry forming the fluorescent surface of a black matrix striped type color picture tube is directly exposed to light using a mercury lamp as a linear light source, in the case of exposing a photoresist for a black matrix, and in the case of exposing a slurry for a phosphor. A method for exposing the fluorescent surface of a color picture tube, characterized in that the effective surface of the panel is made uniform by exposing the panel by changing the length of a linear light source at the center and the periphery depending on the case.