JPH10247459A - Color crt - Google Patents

Abstract

PROBLEM TO BE SOLVED: To improve mislanding near the Y-end against the south-north magnetic field by providing a structure extended in the panel direction in parallel with an H-member skirt on the panel side long side of an inner magnetic shield, setting the width of the H-member skirt larger than the length of a H-member flange, and keeping a fixed spacing with the extended structure. SOLUTION: The panel side long side of the inner magnetic shield of this color CRT is provided with a structure extended in the panel direction in parallel with an H-member skirt 4-1, and the width of the H-member skirt 4-1 is set longer than the length of an H-member flange 4-2, and a fixed spacing is kept with the extension section 2-4 of the panel side long side of the inner magnetic shield. The distance between the H-member flange 4-2 and a mask grille 1 is increased, the magnetic resistance between the H-member flange 4-2 and mask grille 1 is increased, the leakage magnetic field 6-2 is decreased, and mislanding can be reduced.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a color CRT (Cath
ode Ray Tube), especially with regard to color uniformity.

[0002]

2. Description of the Related Art In a color CRT, R (red), G
The electron guns corresponding to the three colors (green) and B (blue) are arranged so as to be shifted from each other. When the electron beams emitted from the electron guns pass through the mask grill just before the panel face, the incident angles at that time Thus, the position where the light strikes the panel face can be restricted. Therefore, if the panel face is separately coated with the R, G, and B phosphors according to the respective projecting positions, it is possible to perform geometrical color selection. FIG. 9 is a perspective view illustrating a mask grill according to the related art. In FIG. 9, 1 is a mask grill (hereinafter, also simply referred to as a grill), 11 is a Y end, 12 is a diagonal, 10-1 is a north-south magnetic field direction (Z-axis direction), 10-2 is the direction of the east-west magnetic field (X-axis direction),
10-3 is the direction of the vertical magnetic field (Y-axis direction).

When a CRT is installed in the presence of terrestrial magnetism, the electron beam receives Lorentz force from terrestrial magnetism and its orbit is bent. When the orbit is bent, the angle of incidence on the mask grill changes, so that the projection position of the panel face shifts, and so-called electron beam mislanding occurs. When the mislanding occurs, the color uniformity on the reproduction screen is reduced, and if the degree is large, the adjacent phosphor is hit and the color shift may be caused.
If the geomagnetism always gives a constant force to the electron beam, it is possible to install a coil or the like for canceling the geomagnetism on the CRT.
Since the relative direction of the terrestrial magnetism changes depending on the installation direction of T, usually, any of the methods of shielding the terrestrial magnetism or installing an internal magnetic shield capable of shaping the direction of the magnetic field in the CRT is adopted. We are dealing.

FIG. 10 is a perspective view showing a conventional example of an internal magnetic shield. 10, 2-1 is an intermediate portion of the internal magnetic shield, 2-6 is a frame shield portion on the panel-side short side of the internal magnetic shield, and 2-7 is V on the electron gun-side short side of the internal magnetic shield. It is a cut part. Since the internal magnetic shield has a cylindrical structure formed of a magnetic material, it can exhibit a shielding effect against east-west direction geomagnetism or vertical direction geomagnetism. However, the magnetic shielding effect is not sufficient for the magnetic field in the north-south direction, and a structure for shaping the magnetic field entering from the electron gun side opening so as not to affect the mislanding is required. here,
In FIG. 9, 10-1 is a north-south magnetic field, 10-2 is an east-west magnetic field, 1
0-3 indicate the directions of the vertical magnetic field.

Japanese Patent Application Laid-Open No. 53-15061 discloses FIG.
(2) discloses an internal magnetic shield in which a V-shaped cut such as 2-7 is cut in the short side on the electron gun side. According to this configuration, the mislanding at the screen diagonal portion with respect to the north-south magnetic field can be reduced, but the mislanding increases with respect to the east-west and vertical magnetic fields.

In the example of installation of the frame shield on the short side exit side indicated by reference numeral 2-6 in FIG. 10, a magnetic path is formed from the internal magnetic shield to the mask grill. The leakage magnetic field from the shield to the inside is reduced, and the mislanding is improved, but this is effective only at the screen diagonal. Here, 11 in FIG.
The portion indicated by is the Y end, and the portion indicated by 12 is the diagonal.

[0007]

SUMMARY OF THE INVENTION An object of the present invention is to improve the mislanding near the Y end with respect to the north-south magnetic field, which cannot be improved by the prior art.

[0008]

A color CRT according to the present invention is a color CRT having a mask grill for color selection and an internal magnetic shield, wherein the long side of the internal magnetic shield on the panel side is an H member. The H-member skirt has a structure extending in the panel direction parallel to the skirt, and the width (Z-axis direction) of the H-member skirt is greater than the length (Y-axis direction) of the H-member flange. To keep a certain interval.

The width of the H member skirt is 1.5 times or more and 3 times or less the length of the H member flange.
This is preferable because a distance can be secured between the electron beam deflected at the upper end of the screen and the diagonal of the screen and the H member skirt that is the source of the leakage magnetic field that causes mislanding.

The fact that the V member is welded to the panel-side surface of the H member flange satisfies the restriction that the V member must be accommodated in a limited space within the glass bulb, while satisfying the restriction. This is preferable because the length can be increased.

Another color CRT according to the present invention is a color CRT having a mask grill for color selection and an internal magnetic shield, wherein the long side of the internal magnetic shield on the panel side is parallel to the H member skirt in the panel direction. And a structure in which the width of the H member flange near the Y-axis is reduced.

When the width of the H member flange is two
The distance between the electron beam deflected to the top of the screen and the diagonal of the screen, which is narrowed between the member welds, and the H member skirt, which is the source of the leakage magnetic field that causes mislanding, It is preferable in that it can be secured.

The fact that the width of the H member flange is reduced to not less than 1/3 and not more than 2/3 of the width of the H member skirt is due to the fact that the electron beam deflected to the upper end of the screen and the diagonal of the screen causes mistakes. This is preferable because a distance can be secured between the H-member skirt, which is a source of the leakage magnetic field that causes landing, and the H-member skirt.

Still another color CRT according to the present invention
Is a color CRT having a mask grill for color selection and an internal magnetic shield, having a structure in which a long side of the internal magnetic shield on the panel side extends toward the panel from the front of the mask grill. And the tip of the protruding structure is folded in the direction toward the tube axis parallel to the mask grill.

The tip of the protruding structure is folded parallel to the mask grill in the direction toward the tube axis, and the folded width is 3 mm or more and 20 mm or less, which indicates that the magnetic field leaks from the internal magnetic shield to the mask grill. In addition, the magnetic field leaking from the internal magnetic shield to the mask grill through the H member skirt portion is reduced, and the magnetic field can escape from the folded portion to the front of the panel.

6 mm or more and 10 m between the extended portion of the long side of the internal magnetic shield on the panel side and the H member skirt.
The provision of the air gap of not more than m can reduce the magnetic field flowing into the H member skirt from the internal magnetic shield, and therefore, the leakage magnetic field from the H member skirt which is the source of the leakage magnetic field causing mislanding Is preferable in that it can be reduced.

Still another color CRT according to the present invention
Is a color CRT having a mask grill for color selection and an internal magnetic shield, wherein a folded portion in a direction toward a tube axis parallel to the mask grill is provided on a long side of the internal magnetic shield on the electron gun side. The distance between the tip of the folded portion and the electron beam trajectory at the time of deflection at the Y end is 1 mm or more and 10
mm or less.

The fact that the height of the folded portion on the long side of the electron gun side of the internal magnetic shield is made lower as it goes to the diagonal portion is due to the fact that the electron beam trajectory at the time of upper end deflection corrects the mislanding. This is preferable in that it can pass through the inside and can secure an interval between the electron beam orbit and the folded portion during diagonal deflection.

[0019] The height of the folded portion is such that the distance from the electron beam trajectory is 1 mm or more and 10 mm or less at both the diagonal portion and the Y end, and the electron beam trajectory corrects mislanding. It is preferable because it can pass through a magnetic field.

Still another color CRT according to the present invention
Is a color CRT having a mask grill for color selection and an internal magnetic shield, wherein the internal magnetic shield has a structure in which a diagonal portion of a long side of the electron gun is cut off.

According to the first configuration of the present invention, the panel-side long side of the internal magnetic shield is extended in the panel direction in parallel with the H member skirt, so that the magnetic resistance of the magnetic path from the internal magnetic shield to the mask grill is extended. , The leakage magnetic field from the intermediate portion of the internal magnetic shield is reduced. Also, by increasing the width of the H member skirt, the position of the flange can be kept away from the grill, so that the amount of magnetic flux flowing from the extension of the long side of the internal magnetic shield to the panel side to the H member can be reduced from the flange. Can be. From the above, mislanding can be reduced.

According to the second configuration of the present invention, the panel-side long side of the internal magnetic shield is extended in the panel direction parallel to the H member skirt, so that the magnetic resistance of the magnetic path from the internal magnetic shield to the mask grille is increased. , The leakage magnetic field from the intermediate portion of the internal magnetic shield is reduced. Also, by reducing the width of the H member flange near the Y end, the distance between the tip of the flange and the electron beam trajectory at the time of deflection of the Y end can be secured, so that the effect of the leakage magnetic field from the H member flange tip can be reduced. Mislanding can be reduced.

According to the third structure of the present invention, the north-south magnetic field near the Y end of the mask grill enters the bent portion by bending the end of the extended portion of the long side of the internal magnetic shield on the panel side. So, from the mask grill H
The magnetic field directed to the member is reduced, and mislanding can be reduced. Further, since a gap is provided between the internal magnetic shield extension and the H member skirt, the magnetic flux flowing from the extension to the H member is reduced, and the magnetic field leaking from the H member flange to the mask grill is reduced, thereby causing mislanding. Can be reduced.

According to the fourth configuration of the present invention, the north-south magnetic field wraps around the long side folded structure on the electron gun side of the internal magnetic shield, and the direction for correcting the mislanding due to the leakage magnetic field from the intermediate portion of the internal magnetic shield. Is generated. By increasing the height of the folded portion in the vicinity of the Y end, the wraparound effect of the magnetic field is promoted, and mislanding can be reduced.

According to the fifth aspect of the present invention, by cutting off the diagonal of the long side of the internal magnetic shield on the electron gun side, the magnetic field does not enter the diagonal portion, and accordingly, the magnetic field is applied to the Y end portion. Collected. Therefore, the above-described effect of wraparound of the magnetic field can be promoted, and mislanding at the end of the screen Y can be reduced.

[0026]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, a color CRT according to the present invention will be described in detail with reference to the accompanying drawings.

Embodiment 1 FIG. 1 is an explanatory cross-sectional view showing a vertical cross-sectional structure of a Y-end portion of a color CRT according to Embodiment 1 of the present invention. FIG. 1A shows a configuration of a conventional example.
(B) is a diagram showing a configuration of the present embodiment. In FIG. 1, reference numeral 1 denotes a mask grill, 2-4 denotes an extended portion of the long side of the internal magnetic shield on the panel side, 3 denotes a V member, 4-1 and 4-11 denote H member skirts,
4-2 is an H member flange, and 13 is a glass valve. The color CRT according to the present invention has a mask grill for color selection and an internal magnetic shield.
In addition, like the conventional color CRT, it includes a glass bulb, a panel face painted with three color phosphors, and an electron gun as an electron beam source. As shown in FIG. 1, the color CRT according to the first embodiment has a structure in which the long side of the internal magnetic shield on the panel side extends in the panel direction in parallel with the H member skirt. -1 (the width in the Z-axis direction, ie, the horizontal direction in FIG. 1) is the length of the H member flange 4-2 (the Y-axis direction, ie, FIG. 1).
The vertical length of the internal magnetic shield is maintained at a certain interval between the internal magnetic shield and the extension 2-4 of the long side on the panel side. The width is larger than that of the configuration of -11. That is, as shown in FIG. 1A, in the case of the conventional example, the extension 2-2 of the long side on the panel side of the internal magnetic shield is used.
4 and the distance between the H member skirt 4-11 and
The distance between the extension 2-4 on the long side of the panel of the internal magnetic shield and the upper end of the V member is different. The width of the H-member skirt is such that the H-member skirt is extended so as not to be affected by the magnetic field leaking from the front end of the flange and to satisfy a condition that a sufficient distance is provided between this portion and the electron beam. . In particular, at the Y end, an H
The width of the member skirt cannot be significantly increased with respect to the length of the H member flange. Therefore, the lower limit of the preferable numerical range in the sense that the ratio is larger than that of the conventional product and the influence of the magnetic field leaking from the front end of the flange is set as follows. The upper limit is limited to a value of 3 times or less due to the restriction that the deformation due to the tension in the ± Y direction of the mask grill is suppressed in addition to the value of 5 times or more.

Further, in the structure of the prior art, the V member 3 is welded to the surface of the H member flange 4-2 on the electron gun side, but in the structure of the present embodiment, the V member is formed on the surface of the H member flange on the panel side. Welded to. This is because the mask grill and the internal magnetic shield must all be housed in the glass bulb 13. When the width of the H member skirt is increased, the V member interferes with the glass valve and cannot be accommodated.
If it is set on the panel side surface of the member flange, it can be accommodated in a glass valve of the same size.

FIG. 2 shows a color CR according to the present embodiment.
FIG. 2 is an explanatory sectional view showing the action of a magnetic field at T, and FIG.
(A) is based on the conventional example, and (b) is based on the configuration of the present embodiment. In FIG. 2, reference numeral 5 denotes an electron beam trajectory, 6-1 denotes a leakage magnetic field, and shows a state of the leakage magnetic field from the flange when the width of the H member skirt is small. 6-2 denotes a leakage magnetic field. , Shows the state of the leakage magnetic field from the flange when the width of the H member skirt is wide, and the same elements as those shown in FIG. 1 are denoted by the same reference numerals (the same applies to FIG. 3 and subsequent figures). . In the configuration of the conventional example, the magnetic flux flowing into the H member via the extension 2-4 on the long side of the panel of the internal magnetic shield flows into the H member flange 4-2.
Leaks into vacuum toward the mask grill 1. The state of the leakage magnetic field from the flange when the width of the H member skirt is small is shown by the leakage magnetic field 6-1 indicated by an arrow in the drawing. However, if the distance between the flange and the mask grill is large as shown in FIG. 1B, the magnetic resistance between the flange and the mask grill increases, and the leakage magnetic field 6-2 decreases. Therefore, mislanding can be reduced. At this time, as described above, since the width of the H member skirt is set to be 1.5 times or more and 3 times or less the length of the H member flange, the leakage magnetic field is less than that of the conventional example without deformation of the mask grill. And mislanding is reduced by more than 2 μm.

Embodiment 2 FIG. 3 is a perspective explanatory view showing a configuration of a second embodiment of the present invention. In FIG. 3, reference numeral 4-3 denotes an H member flange cutout, and reference numeral 9 denotes a V member weld. The color CRT according to the present embodiment has a structure in which the long side of the internal magnetic shield on the panel side extends in the panel direction parallel to the H member skirt, as shown in FIG. The width of the H member flange is reduced. As described above, when the width of the Y end portion of the H member flange 4-2 is reduced (the portion indicated by reference numeral 4-3), the distance between the tip of the H member flange and the electron beam trajectory is secured, and the electron beam is supplied to the flange. The effect of reducing the leakage magnetic field is reduced, as in the first embodiment.

In the embodiment shown in FIG. 3, two V
Between the member welds, the width of the flange is reduced only on the Y axis. This is because the V member is welded to the flange of the H member at the position of reference numeral 9 shown in the figure, and thus the welded portion is secured. Further, the width of the H member flange is reduced to not less than 1/3 and not more than 2/3 of the width of the H member skirt. The reason why the width of the H member flange is limited to 2/3 or less of the width of the H member skirt is to secure the distance between the tip of the H member flange and the electron beam trajectory. The reason for the above limitation is that if the width is reduced to more than 1/3, a problem occurs in the strength of the H member flange. In the present embodiment, since the purpose is to reduce mislanding at the Y end, the flange of the welded portion does not have to be narrow.

Third Embodiment FIG. 4 is a sectional explanatory view for explaining a part of the structure and operation of a color CRT according to a third embodiment of the present invention. FIG. 4A is a sectional view of a conventional structure. (B) is a cross-sectional view near the Y end of the structure according to the present embodiment. In FIG. 4, reference numeral 2-5 denotes a folded portion, which has a structure in which the extended end of the long side of the internal magnetic shield on the panel side protrudes from the front surface of the mask grill in the panel direction, and has a protruded distal end. Are folded in the direction toward the tube axis in parallel with the mask grill.
6-3 shows the north-south magnetic field entering the grill.
Fig. 7 shows the north-south magnetic field entering the internal magnetic shield turn-up and grill. In FIG. 4 (a), there is an extension of the long side of the internal magnetic shield indicated by reference numeral 2-4 as an extension on the long side of the internal magnetic shield on the panel side. Since the extended portion 2-4 of the long side on the panel side has almost no exposure in terms of the surface area covering the panel, the north-south magnetic field coming from the panel side is indicated by reference numeral 6-3 in the drawing. Almost all enter mask grill 1 as if entering. The magnetic field that has entered the mask grill leaks to the H-member flange or to the middle of the internal magnetic shield, which worsens mislanding. At this time, it is preferable that the width of the protruding end of the protruding structure folded parallel to the mask grill is 3 mm or more and 20 mm or less. The reason why the width is limited to 3 mm or more is that a part of the north-south magnetic field entering the mask grill can enter this folded portion,
The reason for limiting the width to 20 mm or less is that the electron beam deflected to the Y end is not blocked by the folded portion before passing through the mask grill and hitting the phosphor screen.

On the other hand, as shown in FIG. 4 (b), a folded portion is provided at the end of the extended portion 2-4 of the long side of the panel of the internal magnetic shield, and the panel of the internal magnetic shield is indicated by reference numeral 2-5. Assuming that the folded portion is an extended portion of the longer side, the folded portion 2-5 is exposed when viewed from the panel side. Therefore, in FIG. As shown by the arrow 6-4 shown in the figure, the north-south magnetic field enters the folded portion of the internal magnetic shield and the grill, and enters the folded portion 2-5 at the tip of the extension of the long side of the internal magnetic shield on the panel side. Therefore, the magnetic field leaking from the mask grill to the H member flange or toward the intermediate portion of the internal magnetic shield is reduced, and mislanding is reduced.

In FIG. 4B, since there is a gap between the H member skirt 4-11 and the internal magnetic shield extension 2-4, the magnetic resistance between them increases, and the H member causes internal magnetic Magnetic flux does not easily flow to the shield extension 2-4. At this time, a distance of 6 mm was set between the extended portion of the long side of the panel of the internal magnetic shield and the H member skirt.
It is preferable that a gap of not less than 10 mm is provided. As described above, the gap between the extension of the long side of the internal magnetic shield on the panel side and the H member skirt is limited to 6 mm or more because the magnetic resistance between the H member skirt and the extension of the internal magnetic shield is folded. This is because the range is larger than the magnetic resistance reaching the extended portion through the portion. The reason why the size is limited to 10 mm or less is to secure a size as large as possible within a range that can be accommodated in the glass bulb.
Therefore, the north-south magnetic field from the panel side is more likely to enter not the mask but the front end folded portion 2-5 of the extension of the long side of the internal magnetic shield on the panel side.

Embodiment 4 FIG. 5 is a perspective explanatory view showing a part of the structure of a color CRT according to Embodiment 4 of the present invention. In FIG. 5, 2
Reference numeral -2 denotes an electron gun-side long side folded portion of the internal magnetic shield.
2 is high at the Y end and low at the diagonal as shown in the figure. Folded part 2 on the long side of electron gun side of this internal magnetic shield
No. -2 is parallel to the mask grill toward the tube axis, and the distance between the tip and the electron beam trajectory at the time of Y-end deflection is 1 mm or more and 10 mm or less. Here, the reason for limiting the distance to 10 mm or less is that it is necessary to secure a tolerance of 1 mm or more from the viewpoint of the mounting accuracy of the internal magnetic shield, and the magnetic field for correcting mislanding at a distance of 10 mm or less is This is to work effectively on the beam.

FIG. 6 shows a color C according to the fourth embodiment.
It is sectional explanatory drawing which shows the effect | action of the magnetic field in RT, and has shown the longitudinal cross section of Y end part. In FIG. 6, 4 is an H member, 5 is an electron beam trajectory, and shows how the electron beam deflected at the Y end passes through the CRT.
Indicates the direction of the magnetic field, and 6-5, 6-6, and 6-7 indicate the directions of the magnetic field in orbit when the north-south magnetic field is applied, respectively. Outside the internal magnetic shield, the magnetic field
5 is not affected by the internal magnetic shield as in the magnetic field shown in FIG. 5, but in the internal magnetic shield, due to the magnetic field leaking from the intermediate portion 2-1 of the internal magnetic shield, the orbit is not affected by the magnetic field shown by reference numeral 6-7. Thus, the magnetic field has a component in the −Y direction. This magnetic field causes the electron beam to be displaced in the −X direction, thereby causing mislanding in the −X direction. However, in the vicinity of the inner magnetic shield entrance turning portion 2-2, the north-south magnetic field is attracted to the magnetic material, and becomes a magnetic field having a component in the + Y direction with respect to the trajectory of the electron beam like the magnetic field indicated by reference numeral 6-6. To displace in the + X direction,
It has the effect of canceling mislanding.

When the Y end of the electron gun-side folded portion 2-2 of the internal magnetic shield is raised and the tip approaches the orbit of the electron beam as in the configuration of the present embodiment, the magnetic field 6-6 wraps around. The angle increases, and the + Y component increases. Therefore, the canceling effect of the magnetic field 6-6 is enhanced, and mislanding can be reduced at the end of the screen Y.

In FIG. 5 showing the configuration of the present embodiment, only the Y end portion of the long side folded portion 2-2 (hereinafter simply referred to as the folded portion 2-2) of the internal magnetic shield on the electron gun side is raised.
The reason why the diagonal portion is set low is to ensure the allowance of the gap between the tip of the folded portion 2-2 and the beam orbit. It is preferable that the height of the folded portion 2-2 be 1 mm or more and 10 mm or less, both at the diagonal portion and at the Y end. Limiting the height of the folded portion 2-2 in this manner is one of the reasons from the viewpoint of the mounting accuracy of the internal magnetic shield.
It is necessary to secure a tolerance of at least 10 mm
This is because a magnetic field for correcting mislanding works effectively on the electron beam by setting the distance as follows. FIG. 7 shows a color CRT in which the panel has a cylindrical shape in the vertical direction.
This shows the state of the trajectory when the electron beam is deflected to each point on the screen. In FIG. 7, 5-1 is an electron beam trajectory when deflected to the screen diagonal, 5-2 and 5
-3 is the electron beam trajectory when deflected to the screen Y end, 7
Denotes a cylindrical panel face, and 8 denotes a raster shape in a plane parallel to the XY plane near the entrance of the internal magnetic shield.

When the panel face is flat, the screen Y
The electron beam trajectory of the end deflection is as shown in 5-2, and the raster shape 8 is rectangular. However, when the Y end of the screen is curved in the + Z direction as compared with the diagonal portion, the electron beam trajectory becomes like 5-3, and the raster shape 8 has the Y end of −Y.
The shape becomes convex in the direction. Therefore, at the time of diagonal deflection, the allowance between the electron beam trajectory and the bent portion becomes strict, so that only the Y end can be increased as in the configuration of the present embodiment.
However, even with such a configuration, the mislanding at the Y end can be reduced.

Fifth Embodiment FIG. 8 is a diagram showing a configuration of a fifth embodiment of the present invention. In FIG. 8, reference numeral 2-3 denotes a cut-off portion at a diagonal portion of the long side of the internal magnetic shield on the electron gun side. When the diagonal portion is cut off in this way, when the north-south magnetic field coming from the electron gun side enters the internal magnetic shield, the magnetic flux concentrates on the Y end portion.
The magnetic field 6-6 shown therein also concentrates near the Y end. Therefore, the canceling effect described in the fourth embodiment is prominent at the Y end, and a reduction in mislanding can be promoted at the Y end of the screen.

Among the embodiments according to the present invention, the best embodiment in practical use is based on the first embodiment, in which the folded side of the long side of the electron gun side of the internal magnetic shield is high at the Y end and is diagonal. In this embodiment, the distance between the tip of the folded portion and the electron beam trajectory is set to 1 mm or more and 10 mm or less at both the diagonal and Y ends. In this best mode, the leakage magnetic field from the flange is reduced, and the electron beam can pass through the magnetic field that corrects the mislanding on the electron gun side of the internal magnetic shield, so that the mislanding with respect to the north-south magnetic field is reduced. The effect is obtained.

[0042]

The color CRT according to the present invention is a color CRT having a mask grill for color selection and an internal magnetic shield, wherein the long side of the internal magnetic shield on the panel side is parallel to the H member skirt. It has a structure extending in the panel direction, and the width of the H-member skirt is made larger than the length of the H-member flange so as to keep a constant distance from the extended structure.
Since the member flange can be kept away from the mask grill, the leakage magnetic field from the H member flange is reduced,
Since it is possible to reduce the mislanding near the edge, the effect of improving the color uniformity on the screen is obtained.

Since the width of the H member skirt is 1.5 times or more and 3 times or less the length of the H member flange, the leakage magnetic field which causes the mislanding is reduced, and the effect that the mislanding can be reduced can be achieved. .

Since the V-member is welded to the panel-side surface of the H-member flange, it has the effect that it can be housed in the same glass bulb as in the prior art.

Another color CRT according to the present invention is a color CRT having a mask grill for color selection and an internal magnetic shield, wherein the long side of the internal magnetic shield on the panel side is parallel to the H member skirt in the panel direction. And the structure in which the width of the H member flange near the Y axis is narrowed, so that the distance between the tip of the H member flange and the electron beam trajectory at the time of Y end deflection can be secured. The leakage magnetic field from the member flange can be reduced, and Y
Since the mislanding near the edge can be reduced, the effect of improving the color uniformity on the screen is achieved.

When the width of the H member flange is two
Since the gap is narrowed between the member welds, the leakage magnetic field from the tip of the H member flange near the Y end is reduced, and the effect that mislanding can be reduced can be achieved.

Since the width of the H member flange is narrowed to not less than 1/3 and not more than 2/3 of the width of the H member skirt, the leakage magnetic field from the tip of the H member flange is reduced near the Y end, resulting in mislanding. The effect that it can reduce is produced.

Still another color CRT according to the present invention
Is a color CRT having a mask grill for color selection and an internal magnetic shield, having a structure in which a long side of the internal magnetic shield on the panel side extends toward the panel from the front of the mask grill. And the tip of the protruding structure is folded in the direction toward the tube axis in parallel with the mask grill, so that the leakage magnetic field between the grill and the H member flange can be reduced, and near the Y end. Can reduce the mislanding of the image, and thus has the effect of improving the color uniformity on the screen.

The tip of the protruding structure is folded parallel to the mask grill in the direction toward the tube axis, and the folded width is 3 mm or more and 20 mm or less, so that the magnetic field leaking from the internal magnetic shield to the mask grill and The magnetic field leaking from the internal magnetic shield to the mask grill through the H member skirt portion is reduced, and the magnetic field can be released from the folded portion to the front of the panel.

A distance of 6 mm or more and 10 m between the extended portion of the inner magnetic shield on the long side of the panel and the H member skirt.
m or less, the magnetic field flowing from the internal magnetic shield to the H member skirt can be reduced, and therefore, the leakage magnetic field from the H member skirt, which is the source of the leakage magnetic field that causes mislanding, can be reduced. It has the effect that it can be reduced.

Still another color CRT according to the present invention
Is a color CRT having a mask grill for color selection and an internal magnetic shield, wherein a folded portion in a direction toward a tube axis parallel to the mask grill is provided on a long side of the internal magnetic shield on the electron gun side. The distance between the tip of the folded portion and the electron beam trajectory at the time of deflection at the Y end is 1 mm or more and 10
mm or less, it is possible to promote the canceling effect of the internal magnetic shield at the folded portion on the long side of the electron gun, and to reduce the mislanding near the Y end. This has the effect of improving color uniformity.

Since the height of the folded portion of the long side of the inner magnetic shield on the electron gun side is reduced as it goes to the diagonal portion, the trajectory of the electron beam at the time of deflection of the upper end of the screen is a magnetic field for correcting mislanding. And the gap between the electron beam trajectory and the folded portion can be secured during diagonal deflection.

The height of the folded portion is such that the distance from the electron beam trajectory is 1 mm or more and 10 mm or less at both the diagonal portion and the Y end. This has the effect of being able to pass through.

Still another color CRT according to the present invention
Is a color CRT having a mask grill for color selection and an internal magnetic shield, which has a structure in which a diagonal portion of the long side of the internal magnetic shield on the electron gun side is cut off. The canceling effect at the folded portion of the long side of the electron gun side of the magnetic shield can be concentrated at the Y end, and mislanding at the Y end can be reduced, so that the effect of improving color uniformity on the screen can be obtained. .

[Brief description of the drawings]

FIG. 1 shows a color CR according to an embodiment of the present invention.
FIG. 3 is an explanatory sectional view showing a configuration of T.

FIG. 2 shows a color CR according to an embodiment of the present invention.
It is sectional explanatory drawing which shows the effect | action of T.

FIG. 3 shows a color C according to another embodiment of the present invention.
FIG. 3 is a perspective explanatory view showing a configuration of an RT.

FIG. 4 shows a color C according to another embodiment of the present invention.
FIG. 3 is an explanatory cross-sectional view showing the configuration and operation of an RT.

FIG. 5 shows a color C according to another embodiment of the present invention.
FIG. 3 is a perspective explanatory view showing a configuration of an RT.

FIG. 6 shows a color C according to another embodiment of the present invention.
It is sectional explanatory drawing which shows the effect | action of RT.

FIG. 7 shows a color C according to another embodiment of the present invention.
It is a perspective explanatory view for explaining RT.

FIG. 8 shows a color C according to another embodiment of the present invention.
FIG. 3 is a perspective explanatory view showing a configuration of an RT.

FIG. 9 is an explanatory perspective view for explaining a conventional technique.

FIG. 10 is a perspective explanatory view showing a conventional example of an internal magnetic shield.

[Explanation of symbols]

Reference Signs List 1 mask grill, 2 internal magnetic shield, 2-1 intermediate portion of internal magnetic shield, 2-2 folded portion of internal magnetic shield on long side of electron gun side, 2-3 cut-off portion of internal magnetic shield on long side of electron gun side 2-4 Extension of long side on panel side of internal magnetic shield, 2-5 Folded part, 2
-6 Frame shield on the short side of panel on the internal magnetic shield, 2-7 V on short side on the gun side of internal magnetic shield
Cut part, 3 V member, 4 H member, 4-1 H member skirt, 4-2 H member flange, 4-3 H
Member flange notch, 5 electron beam track, 9 V member weld, 10 magnetic field direction, 11 Y end, 12
Diagonal, 13 glass bulb.

Claims (13)

[Claims] 1. A color CRT having a mask grill for color selection and an internal magnetic shield, wherein the long side of the internal magnetic shield on the panel side extends in the panel direction parallel to the H member skirt. A collar CRT wherein the width of the H-member skirt is greater than the length of the H-member flange so as to maintain a constant spacing with the extended structure. 2. The color CRT according to claim 1, wherein the width of the H member skirt is 1.5 times or more and 3 times or less the length of the H member flange. 3. The color CR according to claim 2, wherein a V member is welded to a panel-side surface of the H member flange.
T. 4. A color CRT having a mask grill for color selection and an internal magnetic shield, wherein a long side of the internal magnetic shield on the panel side extends in the panel direction parallel to the H member skirt. H near the Y axis
Color CR having a structure in which the width of the member flange is reduced
T. 5. The color CRT according to claim 4, wherein the width of the H member flange is narrowed between two V member welds. 6. The color CRT according to claim 5, wherein the width of the H member flange is reduced to not less than 1/3 and not more than 2/3 of the width of the H member skirt. 7. A color CRT having a mask grill for color selection and an internal magnetic shield, wherein a long side of the internal magnetic shield on the panel side extends from a front side of the mask grill in a panel direction. Having a structure,
And a collar C having a structure in which the tip of the protruding structure is folded in the direction toward the tube axis in parallel with the mask grill.
RT. 8. The color CRT according to claim 7, wherein the tip of the protruding structure is folded in a direction toward the tube axis in parallel with the mask grill, and the folded width is 3 mm or more and 20 mm or less. 9. A space between the extended portion of the long side of the panel of the internal magnetic shield and the H member skirt of 6 mm or more.
The color CRT according to claim 8, wherein a gap of not more than mm is provided. 10. A color CRT having a mask grill for color selection and an internal magnetic shield, wherein a long side of the internal magnetic shield on an electron gun side is parallel to the mask grill in a direction toward a tube axis. And a distance between the tip of the folded portion and the electron beam trajectory at the time of Y-end deflection is 1
Color CR having a structure of not less than 10 mm and not more than 10 mm
T. 11. The color CRT according to claim 10, wherein the height of the folded portion of the long side of the internal magnetic shield on the side of the electron gun is reduced toward the diagonal portion. 12. A height of the folded portion is 1 mm at a distance from the electron beam orbit at both the diagonal portion and the Y end.
The color CRT according to claim 11, wherein the height is not less than 10 mm and not more than 10 mm. 13. A color CRT having a mask grill for color selection and an internal magnetic shield, wherein the internal magnetic shield has a structure in which a diagonal portion of a long side of an electron gun is cut off. CRT.