KR100274827B1 - Shadow mask and its manufacturing method _ - Google Patents

Abstract

The present invention relates to a shadow mask used in a color cathode ray tube for a display and a method of manufacturing the shadow mask, and more particularly, to a method for facilitating the progress of an electron beam and improving a mechanical strength of a shadow mask in manufacturing a color display tube cathode ray tube.

According to the shadow mask of the present invention and the method for manufacturing the shadow mask, it is possible to manufacture the shadow mask with a polygonal shape and the circular hole with a circular shape, mount the shadow mask on the cathode ray tube, rotate the ridge polygon so as to coincide with the advancing direction of the electron beam, The hole and the tube panel can be uniformly formed and the electron beam can be sufficiently passed therethrough according to the position of the through hole in the shadow mask so that the portion not related to the passage of the electron beam is not etched, A taper was formed so that the strength could be improved and the electron beam could pass sufficiently according to each position.

Description

Shadow mask and manufacturing method thereof

The present invention relates to a shadow mask used in a color cathode ray tube for a display and a method of manufacturing the shadow mask. More particularly, the present invention relates to a shadow mask used for a color cathode ray tube A shadow mask and a manufacturing method thereof.

Generally, a shadow mask is a device that functions as a color-selecting electrode that makes an electron beam emitted from an electron gun come in contact with a pixel corresponding to each of R, G, and B on the inner surface of a cathode ray tube panel.

FIG. 1 is an overall view of a shadow mask, which comprises an effective portion 10 formed of a through hole through which an electron beam passes, and an outer peripheral portion 20 capable of being mounted on a cathode ray tube.

FIG. 3 is a cross-sectional view of a through hole formed at the center of the effective portion of the shadow mask according to the prior art, and FIG. 3B is a cross- Sectional view of a through hole formed at the center peripheral portion of the effective portion of the shadow mask according to the embodiment of the present invention.

At the center point A, the small hole 12 is located at the center of the air hole 14 and the small holes 24 are formed in the direction of the electron beam toward the air hole 22 at the points B, C and D around the center.

The electron beam travels from the pores on the side of the electron gun of the shadow mask to the air on the side of the screen and is incident on the inner surface of the cathode ray tube panel. The electron beam passing through the effective portion 10 having a constant arrangement of the through-holes is vertically incident at the central portion of the shadow mask, and incident at a peripheral portion thereof obliquely at an angle by the deflection yoke.

2, 3A, and 3B. In order to facilitate the passage of the electron beam at the peripheral portion, the shadow mask is formed at the positions B, C, and D with respect to the taper 16 of the through- The taper 18 of the formed through hole is formed to be larger so as to facilitate electron beam transmission.

Recently, CDT cathode ray tubes are becoming more and more fixed, such as increasingly flattened, flat-square tube (FST), larger size, and increasing electron beam transmission angle through reduction of tube length. As a result, the shadow mask tends to become finer and larger in all areas, such as the pitch and pore size of the through-hole. Further, due to the dome phenomenon caused by the thermal expansion of the shadow mask, There is also a demand for countermeasures against the occurrence of problems, and also for improving the mechanical strength of the shadow mask in order to alleviate the impact of the cathode ray tube and to enhance the characteristics thereof.

As the cathode ray tube becomes FST and larger, the inclination of the electron beam transmitted to the peripheral portion of the shadow mask is made larger, and the electron beam is required to sufficiently pass through the shadow mask and enter the cathode ray tube panel. For this reason, the taper shown in Fig. 3 should be formed in the peripheral portion of the shadow mask to have a shape larger than that of the prior art.

As a countermeasure for improving the shadowing phenomenon and mechanical strength of the shadow mask, a method of changing the material and thickness of the shadow mask is used, or the pores and the air holes are maintained in the minimum form through which the electron beam can pass and the unnecessary portions are not etched Thereby increasing the volume of the shadow mask and improving the mechanical strength.

However, according to the conventional shadow mask and the method for fabricating the shadow mask constructed as described above, in order to secure the taper 18 of the through hole formed in the peripheral portion of the shadow mask, the small hole 24 and the air hole 22 are moved You have to make a lot of center shift in the direction. In this case, there is a problem that the pore shape on the actual CRT panel is not uniform, the deviation becomes worse, and the quality of the CRT panel is adversely affected.

Accordingly, it is an object of the present invention to provide a shadow mask which facilitates the progress of an electron beam during manufacture of a color display tube (CDT) cathode ray tube and improves the mechanical strength of the shadow mask, And a method of manufacturing the same.

Fig. 1 is an overall configuration diagram of a general shadow mask

2 is a plan view showing a shape of a through hole seen from the screen side of a shadow mask according to the related art

FIG. 3A is a cross-sectional view of a through hole formed at the center of an effective portion of a conventional shadow mask

FIG. 3B is a cross-sectional view of the through hole formed in the peripheral portion of the effective portion of the shadow mask according to the related art

FIG. 4 is a plan view showing the movement of the center of the hole for securing taper of the shadow mask according to the related art.

5 is a plan view showing an effective portion of the shadow mask according to the present invention.

6 is a view showing the shape of the through hole formed in the peripheral portion of the effective portion of the shadow mask according to the present invention

Fig. 7 is a view showing the shape of the airtight and small-diameter circular disc of the shadow mask according to the present invention

8 is a cross-sectional view of the through hole formed in the peripheral portion of the effective portion of the shadow mask according to the present invention

Description of the Related Art [0002]

10: valid part

14, 32: air hole formed in the center portion

12, 24: Pore of the through hole formed at the center portion

16: center taper 18: peripheral taper

20:

22, 42: air hole formed in the peripheral portion

24, 44: Pore of the through hole formed in the peripheral part

52: large plate plate plate 54: small plate plate plate

In order to achieve the above object, a shadow mask manufacturing method of the present invention comprises:

A step of forming a through hole at a central portion where diagonal lines of an approximately square plate intersect with each other to form pores and apertures having different diameters of through holes on the front surface and the back surface,

A step of forming a through hole of a through hole so that the size and shape of the through hole are changed from the central part toward the peripheral part,

A step of forming a circular hole in the air hole,

Applying a photosensitive liquid to a shadow mask on which the large holes and small holes are formed;

A step of exposing and developing both surfaces of the iron plate coated with the photosensitive liquid,

And simultaneously etching the developed steel sheet on both sides.

According to another aspect of the present invention, there is provided a method of manufacturing a shadow mask,

A step of forming a through hole at a central portion where diagonal lines of an approximately square plate intersect with each other to form pores and apertures having different diameters of through holes on the front surface and the back surface,

A step of forming a through hole of a through hole so that the size and shape of the through hole are changed from the central part toward the peripheral part,

A step of forming a circular hole in the air hole,

Applying a photosensitive liquid to a shadow mask on which the large holes and small holes are formed;

A step of exposing and developing both surfaces of the iron plate coated with the photosensitive liquid,

And a step of etching a predetermined amount of the developed steel plate at one time by etching the same at both sides simultaneously.

In order to attain the above object, in the shadow mask of the present invention,

A through hole is formed at a central portion where diagonal lines of an approximately square plate cross each other. A through hole and a through hole having different through hole diameters are formed on the front surface and the rear surface,

A through hole is formed in the central portion so that the size and shape of the through hole are changed from the central portion toward the peripheral portion,

And a circular hole is formed in the center of the air hole.

At this time, the air hole is arranged so as to coincide with the traveling direction of the electron beam in the central portion,

And the central point of the air hole is moved in the direction of travel of the electron beam with respect to the pores at the peripheral portion.

Hereinafter, an embodiment of the present invention will be described in detail with reference to the accompanying drawings.

In all the drawings for explaining the embodiment, those having the same function are denoted by the same reference numerals, and a repetitive description thereof will be omitted.

FIG. 5 is a plan view showing an effective portion of a shadow mask according to the present invention, and FIG. 6 is a view showing the shape of a through hole formed around the effective portion of the shadow mask according to the present invention.

As shown in the figure, the shadow mask according to the present invention is formed by circularly forming the air hole, which is a conventional circular shape, in a central portion and changing its size and shape while moving from the central portion to the peripheral portion.

The pores are formed in a circular shape as in the conventional art, and the long axis (a) of the large aperture is made to coincide with the central portion of the shadow mask, that is, the incident direction of the electron beam, The portion not related to the passage of the electron beam is not etched, thereby improving the mechanical strength of the shadow mask.

The center point of the circular disk plat 52 is moved in the electron beam advancing direction to the small circular plate plat 54 at the peripheral portions B, C, and D formed as described above to secure a sufficient amount of taper so as to facilitate electron beam transmission .

The method of manufacturing a shadow mask of the present invention is a method of manufacturing a shadow mask using a circular disk plate 52 and circular circular disk plat 54 having a circular polygonal shape as shown in Fig. Developing, etching, and the like.

Then, the holes in the air platen 52 are set in the direction of the long axis (a) of the air hole 42 according to the center direction, that is, the traveling direction of the electron beam.

That is, in the shadow mask of the related art, both the air hole and the pore shape have a circular shape as shown in Fig. 2, whereas the shadow mask of the present invention has a circular shape like the conventional one, And is formed into a polygonal shape in which a polygon is formed in a circular shape. Further, the direction of the major axis (a) of the polygon of the air gap is made to coincide with the center direction of the shadow mask, that is, the traveling direction of the electron beam.

As shown in FIG. 5, in the central portion, the air hole 32 is formed into a circular shape and gradually formed into a polygonal shape while going to the peripheral portion. As a result, the size of the through hole in the effective portion 10 of the shadow mask and the direction of the long axis (a) of the through hole are determined according to the corresponding positions. In this manner, the shadow mask peripheral taper 18 can be formed to have a larger size than the conventional one, and the portion of the shadow mask not related to the passage of the electron beam is not etched, thereby increasing the volume or weight of the shadow mask, .

Next, a method of manufacturing the shadow mask will be described with reference to the accompanying drawings.

7, the circular disk plate 52 is formed by forming a polygon in a circular shape, and the size and the major axis (a) direction are formed differently depending on the position of the through hole of the shadow mask. In this case, the pores make a circular plate plat 54 formed into a circular shape like a conventional shape.

The central point of the circular disk plat 52 is moved to the small circular plate plat 54 at the peripheral portions B, C, and D to secure a sufficient amount of taper so as to facilitate electron beam transmission. The large-aperture disk plat 52 and the small-diameter disk plat 54 manufactured as described above are mounted on an exposing machine to expose the both surfaces of the iron plate coated with the photosensitive liquid, respectively, and perform development processing. After the development processing, the iron plate is simultaneously etched on both sides, or a certain amount of etching is performed on both sides simultaneously, and only one side is etched.

Actually, as shown in FIG. 8, the thickness of the shadow mask is varied according to the size of the shadow mask. On the Invar substrate made of 0.13 mm thick, μm , Long axis = 82 μm And a pellet of a polygonal plate of 80 μm Development, and etching in each direction using a circular disk plate of a circular disk plate as shown in Fig. 8, μm , Shortening = 200 μm And the pores are formed at 115 μm And the shadow mask shown in FIG. Then, with respect to the pores, μm By moving the center point, the taper amount is 65 μm Respectively.

As described above, according to the shadow mask of the present invention and its manufacturing method, it is possible to manufacture a large-diameter polygon with a polygonal shape and a circular pore with a circular shape, mount the shadow mask on a cathode-ray tube, rotate In addition, the pores of the through holes and the tube panel are uniformly formed, and at the same time, the electron beam can be sufficiently passed through the through hole in the shadow mask according to the position of the through hole, The taper is formed so that the mechanical strength of the shadow mask can be improved and the electron beam can pass sufficiently according to each position.

Also, in the manufacturing method, too, the airplane platelet is formed into a polygonal shape, so that the shape of the large-diameter circular platelet is different from that of the long axis direction according to the position of the through hole, and the polygonal shape has an effect that the peripheral portion taper can be secured more easily in exposure and etching have.

It will be apparent to those skilled in the art that various modifications, additions and substitutions are possible, within the spirit and scope of the invention, and that such modifications are intended to fall within the scope of the following claims something to do.

Claims (4)

In the shadow mask manufacturing method, A step of forming a through hole at a central portion where diagonal lines of an approximately square plate intersect with each other to form pores and apertures having different diameters of through holes on the front surface and the back surface, A step of forming a through hole of a through hole so that the size and shape of the through hole are changed from the central part toward the peripheral part, A step of forming a circular hole in the air hole, Applying a photosensitive liquid to a shadow mask on which the large holes and small holes are formed; A step of exposing and developing both surfaces of the iron plate coated with the photosensitive liquid, And simultaneously etching the developed steel plate on both sides. In the shadow mask manufacturing method, A step of forming a through hole at a central portion where diagonal lines of an approximately square plate intersect with each other to form pores and apertures having different diameters of through holes on the front surface and the back surface, A step of forming a through hole of a through hole so that the size and shape of the through hole are changed from the central part toward the peripheral part, A step of forming a circular hole in the air hole, Applying a photosensitive liquid to a shadow mask on which the large holes and small holes are formed; A step of exposing and developing both surfaces of the iron plate coated with the photosensitive liquid, Wherein the step of etching the surface of the developed steel sheet comprises etching the surface of only one surface of the steel sheet after etching the predetermined amount of the steel sheet on both surfaces at the same time. In the shadow mask, A through hole is formed at a central portion where diagonal lines of an approximately square plate cross each other. A through hole and a through hole having different through hole diameters are formed on the front surface and the rear surface, A through hole is formed in the central portion so that the size and shape of the through hole are changed from the central portion toward the peripheral portion, Wherein a circular hole is formed in the center of the air hole. The method of claim 3, The air- The center portion is arranged so as to coincide with the traveling direction of the electron beam, And the central point of the air hole is moved in the direction of travel of the electron beam with respect to the pores at the peripheral portion.