JP3523440B2 - Color CRT - Google Patents

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention relates to a color CRT (Cath).
ode Ray Tube, CRT) image quality, especially color uniformity.

[0002]

2. Description of the Related Art In a color CRT, R (red), G
Electron guns corresponding to the three colors (green) and B (blue) are arranged with their positions shifted, and when the electron beams emitted from each pass through the mask grill just before the panel face, the incident angle at that time The position where it hits the panel face can be limited. Therefore, if the panel face is separately coated with R, G, and B phosphors according to the respective projection positions, it becomes possible to geometrically perform color selection. FIG. 9 is a perspective view of 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 portion, 12 is a diagonal portion, 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 the CRT is installed in the presence of geomagnetism, the electron beam receives a Lorentz force from the geomagnetism and its orbit is bent. When the track is bent, the angle of incidence on the mask grill changes, so that the projection position of the panel face shifts, causing so-called mislanding of the electron beam. If mislanding occurs, the color uniformity on the reproduction screen deteriorates, and if the degree is large, the adjacent phosphor is hit, which may cause color misregistration.
If the geomagnetism always gives a constant force to the electron beam, it is possible to install a coil or the like to cancel the geomagnetism on the CRT, but in reality CR
Since the relative direction of the geomagnetism changes depending on the installation direction of T, usually (1) shields the geomagnetism, or (2)
An internal magnetic shield capable of shaping the direction of the magnetic field is provided by one of the methods of installing it in the CRT.

FIG. 10 is a perspective view showing a conventional example of the internal magnetic shield. In FIG. 10, 2-1 is a middle portion of the inner magnetic shield, 2-6 is a frame shield portion of the inner magnetic shield on the panel side short side, and 2-7 is V of the inner magnetic shield side on the electron gun side. It is a cutting part. Since the internal magnetic shield has a tubular structure made of a magnetic material, it can exert a shielding effect on the east-west geomagnetic field or the vertical geomagnetic field. 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 penetrating from the electron gun side opening so as not to affect mislanding is necessary. here,
In FIG. 9, 10-1 is a north-south magnetic field, 10-2 is an east-west magnetic field, 1
0-3 has shown the direction of a perpendicular magnetic field, respectively.

FIG. 10 is disclosed in JP-A-53-15061.
There is disclosed an internal magnetic shield having a V-shaped notch like 2-7 on the short side of the electron gun as shown in FIG. According to this configuration, mislanding at the diagonal portion of the screen with respect to the magnetic fields in the north-south direction can be reduced, but the mislanding increases with respect to the magnetic fields in the east-west direction and the vertical direction.

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

[0007]

SUMMARY OF THE INVENTION An object of the present invention is to improve mislanding in the vicinity of the Y edge with respect to the north-south magnetic field, which could not be improved by the prior art.

[0008]

The color CRT is according to the present invention, in order to solve the problems], a color CRT having a mask grill for color selection, and an internal magnetic shield, the Masukugu
One that is perpendicular to the mask grill on the upper and lower sides of the grill
H member skirt with one long side welded in the opposite direction
And the mass on the other long side of the H member skirt.
H with the ends welded in a direction parallel to the cgrill
With the member flange, the upper side and the lower side
V welded near both short sides of the side H member flange
Has a member, the internal magnetic shield panel long side has a structure extending in parallel to the panel direction to the H member skirt and the H members skirt width (Z-axis direction in the vicinity of the Y-axis ) that have a narrow structure a.

The width of the H member flange is equal to that of the V member.
An electron beam that formed by narrow at between the weld 2箇plants deflected diagonally at the upper end and the screen of the screen bars,
This is preferable in that a distance can be secured between the H member skirt, which is the source of the leakage magnetic field that causes mislanding.

When the width of the H member flange is narrowed to 1/3 or more and 2/3 or less of the width of the H member skirt, the electron beam deflected to the upper end of the screen and the diagonal of the screen may be incorrect. This is preferable in that a distance can be secured between the H member skirt, which is the source of the leakage magnetic field that causes landing.

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 long side of the internal magnetic shield on the electron gun side is provided with a folded portion in a direction parallel to the mask grill and toward a tube axis. And the distance between the tip of the folded portion and the electron beam trajectory at the time of deflection of the Y end is 1 mm or more 10
mm or less , the long side of the inner magnetic shield on the electron gun side
The height of the folded-back part of the
It is lowered as you go to the four corners of the opening.
It has a structure consisting of

The height of the folded portion is such that the distance from the electron beam orbit is 1 mm or more and 10 mm or less at both the diagonal portion and the Y end portion, so that the electron beam orbit 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, which is the four corners of an opening consisting of the long side and the short side of the internal magnetic shield on the electron gun side . It has a structure in which the long sides of the corners are cut off.

According to the first aspect of the present invention, the magnetic resistance of the magnetic path from the internal magnetic shield to the mask grill is extended by extending the panel-side long side of the internal magnetic shield parallel to the H member skirt in the panel direction. Is reduced, the leakage magnetic field from the intermediate portion of the inner magnetic shield is reduced. Further, by narrowing the width of the H member flange near the Y end, the distance between the flange tip and the electron beam orbit at the time of deflection of the Y end can be secured, so that the influence of the stray magnetic field from the H member flange tip can be reduced. You can reduce mislanding.

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

According to the third aspect of the present invention, by cutting off the diagonal side of the long side of the inner magnetic shield on the electron gun side, the magnetic field does not enter the diagonal portion, but the magnetic field is applied to the Y end portion accordingly. Collected. Therefore, since the above-described magnetic field wrap-around effect can be promoted, mislanding at the Y edge of the screen can be reduced.

[0017]

BEST MODE FOR CARRYING OUT THE INVENTION A color CRT according to the present invention will be described in detail below with reference to the accompanying drawings.

Reference Example 1 FIG. 1 is a sectional explanatory view showing a structure of a vertical section of a Y-end portion of a structure of a color CRT according to Reference Example 1 of the present invention.
FIG. 1A is a diagram showing a configuration of a conventional example, and FIG.
It is a figure which shows the structure of the reference example 1 . In FIG. 1, 1 is a mask grille, 2-4 is an extension of the long side of the inner magnetic shield on the panel side, 3 is a V member, and 4-1 and 4-11 are H member skirts. 4-2 is an H member flange, and 13 is a glass valve. A color CRT according to the present invention has a mask grill for color selection and an internal magnetic shield, and like other conventional color CRTs, a glass valve and a panel face coated with three-color phosphors separately. And an electron gun which is an electron beam source. Color CRT related to Reference Example 1
1 has a structure in which the long side of the inner magnetic shield on the panel side extends in the panel direction parallel to the H member skirt, and the width of the H member skirt 4-1 (Z axis direction, that is, The width in the left-right direction in FIG. 1 is longer than the length of the H member flange 4-2 (the length in the Y-axis direction, that is, the length in the vertical direction in FIG. 1), and the extension of the long side of the inner magnetic shield on the panel side. It is designed to keep a constant distance between the two members 2-4 and 2-4, which is larger than the width of the conventional H member skirt 4-11. That is,
As shown in FIG. 1A, in the case of the conventional example, the interval between the extended portion 2-4 of the long side of the inner magnetic shield on the panel side and the H member skirt 4-11 and the panel of the inner magnetic shield. It is different from the distance between the extended portion 2-4 of the long side and the upper end of the V member. The width of the H member skirt has a structure in which the H member skirt is extended so as not to be affected by a magnetic field leaking from the tip of the flange and to satisfy the condition that the distance between this portion and the electron beam is sufficient. . Especially at the Y end, ± Y of the mask grill
The width of the H member skirt cannot be made significantly larger than the length of the H member flange in order to suppress deformation due to tension in the direction. Therefore, the lower limit of the preferable numerical range is that the ratio of the H member skirt to the length of the H member flange is 1. Limited to a value of 5 times or more, plus ± Y of the mask grill
Due to the constraint of suppressing the deformation due to the tension in the direction, the upper limit was limited to 3 times or less.

Further, in the structure of the conventional example, 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 Reference Example 1 , the V member is on the panel side surface of the H member flange. It is welded. This is because the mask grill and the internal magnetic shield must all be contained within the glass bulb 13. When the width of the H member skirt is widened, the V member interferes with the glass valve and cannot be accommodated. However, if the V member welded portion is on the panel side surface of the H member flange as in Reference Example 1 , the glass member of the same size can be used. It will fit.

2A and 2B are cross-sectional explanatory views showing the action of the magnetic field in the color CRT according to the reference example 1. FIG. 2A shows the conventional example, and FIG. 2B shows the configuration of the reference example 1 . In FIG. 2, 5 is an electron beam orbit, and 6-
Reference numeral 1 denotes a leakage magnetic field, which shows the leakage magnetic field from the flange when the width of the H member skirt is narrow.
Reference numeral 2 denotes a leakage magnetic field, which shows a state of the leakage magnetic field from the flange when the width of the H member skirt is wide. In addition, the same elements as those shown in FIG. 1 are denoted by the same reference numerals ( (The same applies to Fig. 3 and later). In the configuration of the conventional example, the magnetic flux flowing into the H member via the extended portion 2-4 of the long side of the inner magnetic shield on the panel side leaks into the vacuum from the H member flange 4-2 toward the mask grill 1. This magnetic field is shown by a leakage magnetic field 6-1 indicated by an arrow in the figure, showing a state of the leakage magnetic field from the flange when the width of the H member skirt is narrow. However, as shown in FIG. 1B, if the distance between the flange and the mask grill is long, 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, 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, so that the mask grille is not deformed and the leakage magnetic field is larger than that in the conventional example. Decreased, mislanding is 2 μm
It is reduced more than that.

[0021] Embodiment 1 FIG. 3 embodiment is a perspective view showing the configuration of the first implementation of the present invention. In FIG. 3, 4-3 is an H member flange notch, and 9 is a welded portion of the V member 3 . Shown in Figure 3
So that the upper and lower sides of the mask grill 1 are
One side of the long side melts in the direction orthogonal to the mask grill.
The H member skirt 4-1 that is in contact with the H member skirt
To the other side of the long side of To 4-1 is parallel to the mask grill
H-member flange with the ends welded in different directions
4-2 and. In addition, the upper side and the lower side
The welding is performed near both short sides of the H member flange 4-2.
It has a V member 3 whose top and bottom are connected by a portion 9.
The color CRT according to the present embodiment has a structure in which the long side of the inner 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 narrowed. In this way, if the width of the Y end portion of the H member flange 4-2 is narrowed (the portion indicated by reference numeral 4-3), the distance between the H member flange tip portion and the electron beam trajectory is secured, and the electron beam is flanged. The magnetic field is less affected by the leakage magnetic field, and the leakage magnetic field is reduced as in Reference Example 1.

In the embodiment shown in FIG. 3, V at two locations is used.
Between the member welds, the width of the flange is narrowed only on the Y axis. This is because the V member is welded to the flange of the H member at the position of the reference numeral 9 shown in the figure, so that the welded portion is secured. Further, the width of the H member flange is narrowed to 1/3 or more and 2/3 or less of the width of the H member skirt. In this way, the width of the H member flange is limited to ⅔ or less of the width of the H member skirt in order to secure the distance between the tip of the H member flange and the electron beam trajectory, while it is ⅓. The reason for limiting the above is that the strength of the H member flange becomes problematic if the width is narrowed to more than 1/3. Since the purpose of the present embodiment is to reduce mislanding at the Y end, the flange of the welded portion does not have to have a narrow width.

Reference Example 2 FIG. 4 is a sectional explanatory view for explaining a part of the constitution and operation of the color CRT according to the reference example 2 of the present invention, and FIG. 4 (a) shows a sectional view of a conventional structure. Yes, (b) is a reference
The sectional view near the Y end of the structure concerning Example 2 is shown. In FIG. 4, reference numeral 2-5 is a folded-back portion, which has a structure in which the tip of the extended portion of the long side of the inner magnetic shield on the panel side extends to the panel direction beyond the front surface of the mask grill, and the tip of the protruding structure. Is folded parallel to the mask grill in the direction toward the tube axis. 6-3 is
The north-south magnetic field enters the grill, and 6-4 shows the north-south magnetic field entering the internal magnetic shield turnaround portion and the grill. In FIG. 4A, there is an extension part of the long side of the inner magnetic shield on the panel side, which is indicated by reference numeral 2-4 as an extension part on the long side of the inner magnetic shield on the panel side. Panel side long side extension 2-4
Has almost no exposure in the sense of the surface area covering the panel, so the north-south magnetic field from the panel side is indicated by reference numeral 6 in the figure.
Almost all go into the mask grill 1 like the way the north-south magnetic field goes into the grill, shown at -3. The magnetic field entering the mask grill leaks to the H member flange or to the middle portion of the internal magnetic shield, which worsens mislanding. At this time, the width where the tip of the protruding structure is folded in parallel with the mask grill is 3 mm or more and 20 mm.
The following is preferable. The reason for limiting the length to 3 mm or more is that a part of the north-south magnetic field entering the mask grill can enter the folding part, and the length is 20 mm.
The reason for limiting to the following is that the electron beam deflected to the Y end is not blocked by the folding part before it impinges on the phosphor screen after passing through the mask grill.

On the other hand, as shown in FIG. 4B, a panel for the internal magnetic shield is provided by providing a folded-back portion at the tip of the extended portion 2-4 of the panel side long side of the internal magnetic shield, and designated by reference numeral 2-5. When viewed from the panel side, such a folded-back portion 2-5 is exposed when the folded-back portion of the extension of the long side is exposed. Therefore, a part of the magnetic field contained in the mask in FIG. As indicated by the arrow 6-4 shown therein, in which the north-south magnetic field enters the inner magnetic shield turn-back portion and the grill, it enters the turn-back portion 2-5 at the tip of the extension of the long side of the inner magnetic shield on the panel side. Therefore, the magnetic field leaking from the mask grill to the H member flange or to the intermediate portion of the inner magnetic shield is reduced, and the mislanding is reduced.

Further, in FIG. 4 (b), 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 is increased, and the internal magnetic field from the H member is increased. Magnetic flux does not easily flow to the shield extension 2-4. At this time, 6 mm between the extension of the long side of the inner magnetic shield on the panel side and the H member skirt.
It is preferable that a void of 10 mm or more is provided. In this way, the gap between the extension of the long side of the inner 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 inner magnetic shield extension is folded back. This is because the magnetic resistance is greater than the magnetic resistance reaching the extended portion through the portion, and the reason why the width is limited to 10 mm or less is to secure the largest possible size within the range that can be accommodated in the glass bulb.
Therefore, the north-south magnetic field from the panel side easily enters not the mask but the folded-back portion 2-5 at the end of the extended side of the inner magnetic shield on the panel side.

Second Embodiment FIG. 5 is a perspective explanatory view showing a part of the structure of a color CRT according to the second embodiment of the present invention. In FIG. 5, 2
Reference numeral -2 is an electron gun side long side turnback portion of the internal magnetic shield, and the electron gun side long side turnback portion of the internal magnetic shield 2-
2 is high at the Y end and low at the diagonal as shown in the figure. Electron gun side long side turnback part 2 of this internal magnetic shield
-2 is directed in parallel with the mask grill toward the tube axis, and the distance between the tip and the electron beam orbit at the time of deflection of the Y end is 1 mm or more and 10 mm or less. Here, the reason why the distance is limited to 10 mm or less is that it is necessary to secure a margin of 1 mm or more from the viewpoint of the mounting accuracy of the internal magnetic shield, and the magnetic field that corrects the mislanding at a distance of 10 mm or less is electronic. This is because it works effectively on the beam.

FIG. 6 is a color C according to the second embodiment.
FIG. 6 is a cross-sectional explanatory view showing an action of a magnetic field at RT, showing a vertical cross section of a Y-end portion. In FIG. 6, 4 is an H member, 5 is an electron beam orbit, 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 fields on the orbit when the north-south magnetic field is applied. Outside the inner magnetic shield, the magnetic field is 6-
Although it is not affected by the internal magnetic shield like the magnetic field shown by 5, inside the internal magnetic shield, due to the effect of the magnetic field leaking from the intermediate part 2-1 of the internal magnetic shield, the magnetic field shown by 6-7 is applied to the trajectory. And a magnetic field having a component in the -Y direction. This magnetic field displaces the electron beam in the -X direction, causing mislanding in the -X direction. However, in the vicinity of the folded portion 2-2 at the entrance of the inner magnetic shield, the north-south magnetic field is attracted to the magnetic substance, and a magnetic field having a component in the + Y direction with respect to the electron beam orbit is generated like the magnetic field indicated by reference numeral 6-6. Is displaced in the + X direction,
It has the effect of offsetting mislanding.

As in the structure of the present embodiment, when the Y-end portion of the electron gun side folded-back portion 2-2 of the internal magnetic shield is raised and the tip is brought close to the electron beam orbit, it goes around the magnetic field 6-6. The angle increases and the + Y component increases. Therefore, the effect of canceling the magnetic field 6-6 is enhanced, and mislanding can be reduced at the Y end of the screen.

In FIG. 5 showing the configuration of the present embodiment, only the Y-end portion of the electron gun side long side turnback portion 2-2 (hereinafter simply called turnback portion 2-2) of the internal magnetic shield is raised,
The diagonal portion is made low in order to secure the margin of the gap between the tip of the folded portion 2-2 and the beam trajectory. The height of the folded-back portion 2-2 is preferably such that the distance from the electron beam orbit is 1 mm or more and 10 mm or less at both the diagonal portion and the Y end. In this way, the height of the folded portion 2-2 is limited from the viewpoint of the mounting accuracy of the internal magnetic shield.
It is necessary to secure a margin of 10 mm or more and 10 mm
This is because the magnetic field that corrects mislanding is effectively applied to the electron beam by setting the distance below. FIG. 7 shows a color CRT whose panel has a cylindrical shape in the vertical direction.
It shows the state of the orbit when the electron beam is deflected to each point on the screen. In FIG. 7, 5-1 is the electron beam orbit when deflected diagonally to the screen, 5-2 and 5
-3 is the electron beam orbit when deflected to the Y edge of the screen, 7
Indicates a cylindrical panel face, and 8 indicates a raster shape on a plane parallel to the XY plane near the entrance of the internal magnetic shield.

If the panel face is flat, the screen Y
The edge-deflected electron beam trajectory 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 compared to the diagonal part, the electron beam orbit becomes like 5-3, and the shape 8 of the raster has the Y end of -Y.
The shape becomes convex in the direction. Therefore, during diagonal deflection, the tolerance between the electron beam orbit and the bent portion becomes strict, so that only the Y end can be made higher as in the configuration of the present embodiment.
However, even with such a configuration, mislanding at the Y end can be reduced.

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

Of the embodiments of the present invention, the best mode for practical use is based on the reference example 1, and the electron gun side long side turnback portion of the internal magnetic shield is high at the Y end portion and low at the diagonal portion. However, the distance between the tip of the folded portion and the electron beam trajectory is 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 the mislanding for the north-south magnetic field is reduced. Get the effect of doing.

[0033]

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

[0034] The width of the H member flange is leakage magnetic field from H member flange tip near the Y edge since been made narrow in between the welds 2箇 plants V member is reduced,
This has the effect of reducing mislanding.

Since the width of the H member flange is narrowed to ⅓ or more and ⅔ or less of the width of the H member skirt, the leakage magnetic field from the tip of the H member flange near the Y end is reduced, resulting in mislanding. The effect that can reduce.

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 long side of the internal magnetic shield on the electron gun side is provided with a folded portion in a direction parallel to the mask grill and toward a tube axis. And the distance between the tip of the folded portion and the electron beam trajectory at the time of deflection of the Y end is 1 mm or more 10
Since it has a structure of less than mm, it is possible to promote the offsetting effect at the folded portion of the long side of the inner magnetic shield on the electron gun side, and it is possible to reduce the mislanding near the Y end. It has the effect of improving color uniformity.

The length of the inner magnetic shield on the electron gun side
The height of the folded part of the side becomes lower as it goes to the diagonal part.
Therefore, the electron beam trajectory when deflecting the upper edge of the screen is
Can pass through a magnetic field that corrects for mislanding, and
Securing the space between the electron beam orbit and the turn-back part during diagonal deflection
It has the effect of being able to.

Since the height of the folded portion is such that the distance from the electron beam orbit is 1 mm or more and 10 mm or less at both the diagonal portion and the Y end, the electron beam orbit is in a magnetic field for correcting mislanding. The effect of being able to pass through is produced.

Still another color CRT according to the present invention
Includes a mask grill for color selection, a color CRT having an internal magnetic shield, with a long side portion of the diagonal portion of the electron gun side long side of the internal magnetic shield is cut off structure Therefore, the canceling effect at the folded part of the long side of the electron gun side of the internal magnetic shield can be concentrated at the Y end, and mislanding at the Y end can be reduced, improving color uniformity on the screen. Has the effect of

[Brief description of drawings]

FIG. 1 is a cross-sectional explanatory view showing a configuration of a color CRT according to Reference Example 1 of the present invention.

FIG. 2 is a cross-sectional explanatory view showing the operation of the color CRT according to Reference Example 1 of the present invention.

[3] Color CR according to Embodiment 1 of implementation of the present invention
It is isometric view explanatory drawing which shows the structure of T.

FIG. 4 is a cross-sectional explanatory view showing the configuration and action of a color CRT according to Reference Example 2 of the present invention.

[5] according to Embodiment 2 of implementation of the present invention the color CR
It is isometric view explanatory drawing which shows the structure of T.

[6] according to a second implementation of the present invention the color CR
It is a section explanatory view showing an operation of T.

[7] The color CR according to Embodiment 2 of implementation of the present invention
It is a perspective explanatory view for description of T.

Color CR involved in the implementation of the third [8] The present invention
It is isometric view explanatory drawing which shows the structure of T.

FIG. 9 is a perspective explanatory 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]

1 mask grill, 2 inner magnetic shield, 2-1 middle part of inner magnetic shield, 2-2 folded part of long side of inner magnetic shield on electron gun side, diagonally cut off part of long side of inner magnetic shield on electron gun side 2-4 Extension part of the long side of the inner magnetic shield on the panel side, 2-5 Folded part, 2
-6 Frame shield on the short side of the inner magnetic shield on the panel side, 2-7 V on the short side of the inner magnetic shield on the electron gun side
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 the electron beam orbit, 9 welds V member 10 the direction of the magnetic field, 11 Y end, 12
Diagonal part, 13 glass bulb.

─────────────────────────────────────────────────── --- Continuation of the front page (56) References JP-A-2-139829 (JP, A) JP-A-5-54816 (JP, A) JP-A-7-192647 (JP, A) JP-A-4- 357651 (JP, A) JP-A-5-159714 (JP, A) JP-A-53-15061 (JP, A) Actual Kaihei 5-62948 (JP, U) JP-A-50-5718 (JP, Y1) (58) Fields investigated (Int.Cl. ⁷ , DB name) H01J 29/02

Claims (6)

(57) [Claims] 1. A color CRT having a mask grill for color selection and an internal magnetic shield, wherein the mask grill is provided on an upper side and a lower side of the mask grill.
H men whose one side on the long side is welded in the direction orthogonal to
Bus cart and the other long side of the H member skirt
Melt the end so that it is parallel to the mask grill.
With the H member flange in contact with the above,
Melt near both short sides of the H-side flange on the side and the lower side.
Has a V member are contact, has a structure in which the panel long-side of the internal magnetic shield extending parallel to the panel direction to the H member skirt and the H member flange width in the vicinity of the Y-axis Color CRT with a narrow structure. 2. The width of the H member flange is equal to that of the V member.
Claim made to be narrower in between the welds 2箇 plants Nba
1. Color CRT described in 1 . 3. The color CRT according to claim 2, wherein the width of the H member flange is narrowed to 1/3 or more and 2/3 or less of the width of the H member skirt. 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 electron gun side extends in a direction parallel to the mask grill and toward a tube axis. It has a turnback portion, and the distance between the tip of the turnback portion and the electron beam trajectory at the time of deflection of the Y end is 1 m.
m or more and 10 mm or less , and the electric potential of the internal magnetic shield is
The height of the folded portion of the long side of the child gun is shorter than that of the long side of the electron gun.
I went to the diagonal corners of the four corners of the opening consisting of
A color CRT with a lowered structure. 5. The color CRT according to claim 4 , wherein the height of the folded portion is such that the distance from the electron beam orbit is 1 mm or more and 10 mm or less at both the diagonal portion and the Y end portion. 6. A color CRT having a mask grill for color selection and an internal magnetic shield, the opening of the internal magnetic shield having a long side and a short side on an electron gun side .
A color CRT having a structure in which the long sides of the four corners, the diagonal parts , are cut off.