JPH10208657A - Color cathode ray tube - Google Patents

Abstract

[PROBLEMS] To provide a color cathode ray tube which can prevent the occurrence of bright and dark fringes caused by interference in a display image, that is, a so-called raster moiré phenomenon, and can provide an inexpensive shadow mask assembly. SOLUTION: The panel comprises a panel portion having a fluorescent film formed on the inner surface of a face plate, a neck portion accommodating an electron gun, and a funnel portion connecting the panel portion and the neck portion. In a color cathode ray tube having a shadow mask having a large number of electron beam passage holes 15 disposed opposite to the optical film, the shadow mask comprises a plurality of electron beam passage holes 15 arranged in a plurality of rows 16
At least a part of the horizontal bridging portion 17 between the adjacent electron beam passage holes 15 in the plurality of rows 16 has a portion extending in a direction other than the horizontal direction, for example, an oblique shape.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a color cathode ray tube and, more particularly, to a method of partially changing the arrangement of a large number of electron beam passage holes provided in a shadow mask to generate a raster moire phenomenon in a displayed image. The present invention relates to a color cathode ray tube in which is suppressed.

[0002]

2. Description of the Related Art Generally, a color cathode ray tube has a panel portion disposed on a front side, a neck portion disposed on a rear side,
A vacuum envelope (glass bulb) comprising a panel portion and a funnel portion connecting the neck portion is provided. The panel portion has a fluorescent film adhered to the inner surface of the face plate, and a shadow mask assembly is fixedly disposed inside the panel portion so as to face the fluorescent film. An in-line type electron gun is housed inside the neck portion, and a magnetic shield is arranged inside a joint portion between the panel portion and the funnel portion. A deflection yoke is mounted on the outside of the joint between the funnel and the neck. Further, the shadow mask assembly includes a shadow mask having a large number of electron beam passage holes and a support frame to which the shadow mask is attached, and the support frame to which the shadow mask is attached is fixedly arranged inside the panel portion.

During operation of such a known color cathode ray tube,
The three electron beams (R, G, B) emitted from the in-line type electron gun are appropriately deflected by the deflection yoke, pass through different electron beam passage holes of the shadow mask, and correspond to the corresponding portions on the fluorescent film. The pixels of the colors (R, G, B) are illuminated to emit light, and a required color image is displayed on the face plate.

In this case, a plurality of electron beam passage holes formed in the shadow mask are arranged in a vertically long rectangular shape (slot type), a circular shape (dot type), and a straight line in the vertical direction. A linear shape (grid type) extending in a shape is known.

FIGS. 6, 7 and 8 are plan views showing examples of the arrangement of a large number of electron beam passage holes formed in a known shadow mask. FIG. 7, FIG. 7 shows a dot type configuration example, and FIG. 8 shows a grid type configuration example, all of which show a part of a shadow mask in an enlarged manner.

FIG. 6 shows a configuration example of the slot type.
As shown in the figure, a configuration in which a plurality of electron beam passage holes 62 in which a plurality of substantially rectangular electron beam passage holes 61 long in the vertical direction are connected in the vertical direction are arranged in parallel at substantially equal intervals over a plurality of rows. Thus, each electron beam passage hole row 62 is
Horizontal bridging portion 6 between adjacent electron beam passing holes 61
3 are provided, and the arrangement positions of the electron beam passage holes 61 and the horizontal bridging portions 63 in the horizontal direction coincide with every other row.

As shown in FIG. 7, an example of the dot type configuration is such that an electron beam passage hole array 72 in which a plurality of circular electron beam passage holes 71 are connected in a vertical direction is arranged at substantially equal intervals in a parallel state. In each of the electron beam passage holes 72, a horizontal bridging portion 73 is provided between adjacent electron beam passing holes 71, and the electron beam passing holes 71 and the horizontal bridging are arranged. The configuration is such that the location of the portion 73 in the horizontal direction matches every other row.

FIG. 8 shows an example of a grid type configuration.
As shown in the figure, the linear electron beam passing holes 81 extending in the vertical direction are arranged in a plurality of rows at substantially equal intervals in a parallel state, and between the electron beam passing holes 81 adjacent in the horizontal direction. The configuration is such that a belt-like bridging portion 82 is provided.

[0009]

A known color cathode ray tube in which the arrangement of the electron beam passage holes of the shadow mask is a slot type or a dot type is such that an electron beam emitted from an in-line type electron gun is directed in a horizontal direction. When scanning, the electron beam passage hole 7 of the shadow mask
A horizontal bridge 73 that vertically separates 1, 81;
Since the electron beam is temporarily blocked at the location 83,
The horizontal scanning bright lines of the display image periodically produce a large difference in brightness. On the other hand, the electron beam passing holes 71 and 81 of the shadow mask are also regularly arranged in the horizontal direction. Of the horizontal scanning lines and the arrangement cycle of the electron beam passage holes 71 and 81 themselves, and the bright and dark fringes due to these interferences appear on the display screen. However, there is a problem that a phenomenon that appears, that is, a so-called raster moire phenomenon occurs.

On the other hand, in a known color cathode ray tube in which the arrangement shape of the electron beam passage holes of the shadow mask is a grid type, there is no horizontal bridging portion on each electron beam passage hole 81, so that the horizontal bridge portion is not provided. No bright and dark periods occur in the scanning bright line, and so-called raster moire phenomenon does not occur.

However, in a known color cathode ray tube in which the arrangement shape of the electron beam passage holes of the shadow mask is a grid type, when the shadow mask is mounted on the mask frame, the band-like bridging portion 82 is not bent so as to be bent. Must be installed with strong tension applied,
In addition to requiring a robust mask frame for that purpose, in order to prevent the band-like bridging portion 82 of the shadow mask attached to the mask frame from generating resonance like a string,
A vibration isolating means such as attaching a thin anti-sway wire to the surface of the shadow mask is required, which leads to a problem that the manufacturing cost of assembling the shadow mask is increased as a whole, and furthermore, depending on the content of the display screen, There is also a problem that the steady rest wire attached to the mask becomes noticeable.

The present invention solves these problems, and an object of the present invention is to prevent the occurrence of bright and dark fringes caused by interference in a display image, that is, a so-called moire phenomenon, and to obtain an inexpensive shadow mask assembly. An object of the present invention is to provide a color cathode ray tube.

[0013]

In order to achieve the above object, a color cathode ray tube according to the present invention has a plurality of electron beam passage holes of a shadow mask which are vertically arranged in parallel in a plurality of rows, and adjacent rows in each row. At least a part of the horizontal bridging portion between the electron beam passage holes is provided with a portion having a portion extending in a direction other than the horizontal direction.

According to the above means, when the electron beam is scanned in the horizontal direction, the electron beam is temporarily interrupted at the position where the horizontal bridging portion of the shadow mask is arranged, and the horizontal scanning bright line of the display image is periodically generated. Even if a difference in brightness occurs, at least a part of the horizontal bridging portion has a portion extending in a direction other than the horizontal direction. It is much smaller than the difference in brightness between horizontal scanning lines obtained by the mask, and as a result, the degree of interference caused by the period of the horizontal scanning lines and the inherent arrangement period of the electron beam passage holes is significantly reduced. As a result, it is possible to suppress a raster moiré phenomenon appearing on the display screen.

[0015]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS In a preferred embodiment of the present invention, a color cathode ray tube comprises a panel portion having a fluorescent film formed on the inner surface of a face plate, a neck portion accommodating an electron gun, and a panel portion and a neck portion. A shadow mask having a plurality of electron beam passage holes, the shadow mask having a plurality of electron beam passage holes, and comprising a funnel portion connected to the phosphor film at least inside the panel portion. The holes are formed and arranged in a plurality of rows parallel to the vertical direction, and at least a part of a horizontal bridging portion between adjacent electron beam passing holes in the plurality of rows has a shape having a portion extending in a direction other than the horizontal direction. Things.

According to one embodiment of the present invention, the horizontal bridging portion is of an oblique shape forming an acute angle with respect to the horizontal direction.

According to another embodiment of the invention, the horizontal bridging portion is of the shape of an arrow that intersects at two acute angles to the horizontal.

According to yet another embodiment of the present invention,
The horizontal bridging portion has a stepped shape, part of which extends in the vertical direction.

According to these embodiments of the present invention, when the electron beam is scanned in the horizontal direction, the electron beam is temporarily blocked at the position where the horizontal bridge portion of the shadow mask is arranged, and the displayed image is displayed. Although the horizontal scanning bright line periodically causes a difference in brightness, a shape having a portion where at least a part of the horizontal bridging portion of the shadow mask extends in a direction other than the horizontal direction, that is, an oblique shape, an arrow shape, Because of the stepped shape and the like, the difference in brightness between the horizontal scanning lines is significantly smaller than the difference in brightness between the horizontal scanning lines obtained in a known shadow mask of this type. As a result, the degree of interference caused by the period of light and dark of the horizontal scanning bright line and the inherent arrangement period of the electron beam passage holes is greatly reduced, and light and dark stripes on the display screen caused by such interference, so-called appearing on the display screen Raster moiré phenomenon can be suppressed.

Further, according to the embodiments of the present invention, it is not necessary to arrange the electron beam passage holes of the shadow mask in a grid type, so that the manufacturing cost of the shadow mask assembly can be reduced. it can.

[0021]

Embodiments of the present invention will be described below with reference to the drawings.

FIG. 1 is a sectional view showing a schematic structure of an embodiment of a color cathode ray tube according to the present invention.

In FIG. 1, 1 is a panel portion, 1F is a face plate, 2 is a neck portion, 3 is a funnel portion, 4 is a fluorescent film, 5 is a shadow mask assembly, 6 is a shadow mask, 7 is a support frame, 8 Is the internal magnetic shield, 9
Is a deflection yoke, 10 is an electron gun, 11 is a purity adjustment magnet, 12 is a center beam static convergence adjustment magnet, 13 is a side beam static convergence adjustment magnet, and 14 is an electron beam.

A vacuum envelope (bulb) constituting the color cathode ray tube is disposed on the front side and has a panel section 1 having a substantially rectangular face plate 1F, and is disposed on the rear side.
It comprises an elongated cylindrical neck portion 2 containing an electron gun 9 therein, and a substantially funnel-shaped funnel portion 3 connecting the panel portion 1 and the neck portion 2. In the panel section 1, a fluorescent film 4 is formed on the inner surface of the face plate 1F, and a shadow mask assembly 5 is fixedly disposed inside the panel portion 1 so as to face the fluorescent film 4. The shadow mask assembly 5 includes a shadow mask 6 having many electron beam passage holes (not shown), and a support frame 7 on which the shadow mask 6 is mounted. 1 is fixedly arranged on the inner peripheral portion.
An internal magnetic shield 8 is provided inside the joint between the panel unit 1 and the funnel unit 3, and a deflection yoke 9 is attached outside the joint between the funnel unit 3 and the neck unit 2. The neck part 2 has a purity adjustment magnet 1
1. A center beam static convergence adjusting magnet 12 and a side beam static convergence adjusting magnet 13 are arranged side by side. Electron gun 1
The three electron beams 14 (only one is shown in FIG. 1) emitted from the laser beam 0 are deflected by a deflection yoke 9 in a predetermined direction, and then are passed through different electron beam passage holes of the shadow mask 6 to emit fluorescent light. The light impinges on the optical film 4.

In this case, the operation of the color cathode ray tube of the present embodiment, that is, the image display operation is almost the same as the image display operation of the known color cathode ray tube of this type, and such operation is performed in the technical field of the related art. Is well known, and the description of the image display operation in the color cathode ray tube of the present embodiment will be omitted.

FIG. 2 is an enlarged plan view showing a part of the shadow mask 6 used in the color cathode ray tube shown in FIG. 1 shows a first configuration example.

In FIG. 2, reference numeral 15 denotes an electron beam passage hole;
Reference numeral 16 denotes an electron beam passage hole array, reference numeral 17 denotes a horizontal bridging portion, and other components which are the same as those shown in FIG.

In this first configuration example, a plurality of electron beam passage holes 16 formed by connecting a plurality of vertically long electron beam passage holes 15 in the vertical direction are arranged in parallel at substantially equal intervals. The electron beam passing hole rows 16 are provided with horizontal bridging portions 17 between adjacent electron beam passing holes 15. Each of the horizontal bridging portions 17 has an oblique shape that forms an acute angle in the counterclockwise direction with respect to the horizontal direction. The horizontal arrangement positions of the portions 17 are provided at positions corresponding to every other row.

FIG. 3 is an enlarged plan view showing a part of the shadow mask 6 used in the color cathode ray tube shown in FIG. 2 shows a configuration example.

In FIG. 3, reference numeral 18 denotes an electron beam passage hole;
Reference numeral 19 denotes an electron beam passage hole array, reference numeral 20 denotes a horizontal bridging portion, and other components which are the same as those shown in FIG.

In the second configuration example, a plurality of electron beam passage holes 19 formed by connecting a plurality of vertically long electron beam passage holes 18 in the vertical direction are arranged in parallel at substantially equal intervals. Each electron beam passage hole array 19 has a horizontal bridging portion 20 provided between adjacent electron beam passage holes 18. These horizontal bridging portions 20 have a first oblique shape that forms an acute angle counterclockwise with respect to the horizontal direction, and a second oblique shape that forms an acute angle clockwise with respect to the horizontal direction. In each of the electron beam passage hole rows 19, the horizontal arrangement of the electron beam passage holes 18 is provided at a position corresponding to every other row. The arrangement positions of the first oblique shape and the second oblique shape of the horizontal bridging portion 20 are provided at positions where they are aligned in every other row.

FIG. 4 is an enlarged plan view showing a part of the shadow mask 6 used in the color cathode ray tube shown in FIG. 3 shows a configuration example.

In FIG. 4, reference numeral 21 denotes an electron beam passage hole;
Reference numeral 22 denotes an electron beam passage hole array, 23 denotes a horizontal bridging portion, and other components that are the same as those shown in FIG.

In the third configuration example, a plurality of electron beam passage holes 22 formed by connecting a plurality of vertically long electron beam passage holes 21 in the vertical direction are arranged in parallel at substantially equal intervals. The electron beam passage hole arrays 22 are provided with horizontal bridging portions 23 between adjacent electron beam passage holes 21. Each of the horizontal bridging portions 23 has an arrow shape that intersects at an acute angle in two directions, counterclockwise and clockwise with respect to the horizontal direction. The horizontal arrangement positions of the electron beam passage holes 21 and the horizontal bridging portions 23 are provided at such positions as to coincide with every other row.

FIG. 5 is an enlarged plan view showing a part of the shadow mask 6 used in the color cathode ray tube shown in FIG. 13 shows a fourth configuration example.

In FIG. 5, reference numeral 24 denotes an electron beam passage hole;
Reference numeral 25 denotes an electron beam passage hole array, reference numeral 26 denotes a horizontal bridging portion, and other components which are the same as those shown in FIG. 1 are denoted by the same reference numerals.

In the fourth configuration example, a plurality of electron beam passage holes 25, which are formed by connecting a plurality of vertically long electron beam passage holes 24 in the vertical direction, are arranged in parallel at substantially equal intervals. The electron beam passing hole rows 25 are provided with horizontal bridging portions 26 between adjacent electron beam passing holes 24. Each of the horizontal bridging portions 26 has a stepped shape in which a part of the intermediate region bends from the horizontal direction to the vertical direction and extends. The horizontal arrangement portions of the direction bridging portions 26 are provided at positions that coincide with every other row.

The shadow mask 6 according to any one of the first to fourth examples of the arrangement of the electron beam passage holes.
In the color cathode ray tube provided with the electron beam 14, when the electron beam 14 is scanned in the horizontal direction, the electron beam 14 is temporarily blocked at the arrangement positions of the horizontal bridging portions 17, 20, 23, 26 of the shadow mask 7, The horizontal scanning bright line of the display image periodically causes a difference in brightness, but the horizontal bridging portion 1
7, 20, 23, 26 have at least a portion having a portion extending in a direction other than the horizontal direction, for example, an oblique shape,
Because of the arrow shape and the step shape, the difference between the brightness of this horizontal scanning bright line is obtained in a known shadow mask of this type (having a horizontal bridge extending entirely in the horizontal direction). Since the difference between the brightness of the horizontal scanning lines is significantly smaller than that of the horizontal scanning lines, the degree of interference caused by the period of the light and dark of the horizontal scanning lines and the inherent arrangement period of the electron beam passage holes 15, 18, 21, and 24 is remarkable. Reduced
It is possible to suppress a raster moiré phenomenon appearing on the display screen.

In this embodiment, the case where the shape of the horizontal bridging portions 17, 20, 23, 26 in the shadow mask 6 is an oblique shape, an arrow shape, or a step shape has been described as an example. The shape of the horizontal bridging portions 17, 20, 23, 26 of the shadow mask 6 according to the present invention is not limited to those described above. Of course, any shape may be used as long as it is not obstructed.

[0040]

As described above, according to the present invention, when the electron beam is scanned in the horizontal direction, the electron beam is temporarily blocked at the position where the horizontal bridging portion of the shadow mask is arranged, and the displayed image is displayed. Even if the horizontal scanning luminescent line periodically generates a difference in brightness, the shadow mask has a shape in which at least a part of the horizontal bridging portion has a portion extending in a direction other than the horizontal direction, that is, an oblique shape, an arrow. Due to the shape of the mold, the step shape, etc., the difference in the brightness of this horizontal scanning line is significantly smaller than the difference in the brightness of the horizontal scanning line obtained in a known shadow mask of this type, and as a result, As a result, the degree of interference caused by the light-dark cycle of the horizontal scanning bright line and the inherent arrangement cycle of the electron beam passage holes is greatly reduced, and the light-dark stripes on the display screen caused by such interference and the current There is an effect that it becomes possible to suppress the so-called raster moire phenomenon.

Further, according to the present invention, since it is not necessary to arrange the electron beam passage holes of the shadow mask in a grid type, the production cost of the shadow mask assembly can be reduced. is there.

[Brief description of the drawings]

FIG. 1 is a sectional view showing a schematic configuration of an embodiment of a color cathode ray tube according to the present invention.

FIG. 2 is a plan view showing a first configuration example of an arrangement shape of a large number of electron beam passage holes formed in a shadow mask of the color cathode ray tube shown in FIG.

FIG. 3 is a plan view showing a second configuration example of an arrangement shape of a large number of electron beam passage holes formed in a shadow mask of the color cathode ray tube shown in FIG.

FIG. 4 is a plan view showing a third configuration example of an arrangement shape of a large number of electron beam passage holes formed in a shadow mask of the color cathode ray tube shown in FIG.

FIG. 5 is a plan view showing a fourth configuration example in an arrangement shape of a large number of electron beam passage holes formed in a shadow mask of the color cathode ray tube shown in FIG.

FIG. 6 is a plan view showing a configuration example of a slot type in an arrangement shape of a large number of electron beam passage holes formed in a known shadow mask.

FIG. 7 is a plan view showing a configuration example of a dot type in an arrangement shape of a large number of electron beam passage holes formed in a known shadow mask.

FIG. 8 is a plan view showing a grid-type configuration example of an arrangement shape of a large number of electron beam passage holes formed in a known shadow mask.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 Panel part 1F Face plate 2 Neck part 3 Funnel part 4 Fluorescent film 5 Shadow mask assembly 6 Shadow mask 7 Support frame 8 Internal magnetic shield 9 Deflection yoke 10 Electron gun 11 Purity adjustment magnet 12 Center beam static convergence adjustment magnet 13 Side Beam static convergence adjusting magnet 14 Electron beam 15, 18, 21, 24 Electron beam passage hole 16, 19, 22, 25 Electron beam passage hole array 17, 20, 23, 26 Horizontal bridge

Claims (4)

[Claims] 1. A panel comprising: a panel having a fluorescent film formed on an inner surface of a face plate; a neck accommodating an electron gun; and a funnel connecting the panel and the neck. And a shadow mask having a large number of electron beam passage holes disposed opposite to the phosphor film inside the color cathode ray tube, wherein the shadow mask has a plurality of electron beam passage holes arranged in parallel in a vertical direction. A color cathode ray tube, wherein at least a part of a horizontal bridging portion between adjacent electron beam passage holes in the plurality of rows has a portion extending in a direction other than the horizontal direction. 2. The color cathode ray tube according to claim 1, wherein the horizontal bridging portion has an oblique shape that forms an acute angle with respect to the horizontal direction. 3. The color cathode ray tube according to claim 1, wherein the horizontal bridging portion has an arrow shape that intersects the horizontal direction at two acute angles. 4. The color cathode ray tube according to claim 1, wherein the horizontal bridging portion has a stepped shape with a part extending in the vertical direction.