JP4170791B2 - Cathode ray tube - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a cathode ray tube such as a color picture tube, and more particularly to a cathode ray tube capable of effectively reducing a deflection power and a leakage magnetic field generated by a deflection yoke.
[0002]
[Prior art]
As an example of a cathode ray tube, a color picture tube is shown in FIG. The color picture tube includes a substantially rectangular glass panel 1, a funnel-shaped glass funnel 2 connected to the panel 1, and a cylindrical glass neck connected to the small-diameter end of the funnel 2. 3 vacuum envelope. The inner surface of the panel 1 is provided with a phosphor screen 4 composed of a three-color phosphor layer in the form of dots or stripes that emit blue, green, and red, and is opposed to the phosphor screen 4 on the inner side. A shadow mask 5 having a large number of electron beam passage holes is disposed. An electron gun 7 that emits a three-electron beam 6 is disposed in the neck 3. Further, a deflection yoke 8 is mounted outside the funnel 2 near the neck 3 side. Then, the three electron beams 6 emitted from the electron gun 7 are deflected horizontally and vertically by the horizontal and vertical deflection magnetic fields generated by the deflection yoke 8, and the phosphor screen 4 is horizontally and vertically scanned through the shadow mask 5. By doing so, a structure for displaying a color image is formed.
[0003]
In such a color picture tube, the electron gun 7 is an in-line type electron gun that emits a single row of three electron beams 6 passing on the same horizontal plane, and the single row of three electron beams 6 emitted from this electron gun is deflected. The horizontal deflection magnetic field generated by the yoke 8 is a pin cushion type and the vertical deflection magnetic field is a barrel type. By deflecting with the horizontal and vertical deflection magnetic fields, three electrons are arranged in a line over the entire screen without requiring special correction means. Self-convergence in-line color picture tubes that concentrate the beam 6 have been widely put into practical use.
[0004]
In such a cathode ray tube, it is an important issue to reduce the power consumption of the deflection yoke 8 which is the largest power consumption source. In other words, in order to increase the screen brightness, the anode voltage for finally accelerating the electron beam must be increased, and in order to support OA equipment such as HD (High Definition) TV and PC (Personal Computer). The deflection frequency must be increased, but all of these increase the deflection power. Particularly for deflection by high frequency, the deflection magnetic field tends to leak out of the cathode ray tube. For this reason, restrictions on leakage magnetic fields are strengthened for PCs in which an operator approaches the cathode ray tube.
[0005]
As a means for reducing the leakage magnetic field, a method of adding a compensation coil has been generally used. However, when a compensation coil is added in this way, the power consumption of the PC increases accordingly.
[0006]
Therefore, to reduce the deflection power and leakage magnetic field, the neck diameter of the cathode ray tube is reduced and the outer diameter near the neck side of the funnel to which the deflection yoke is attached is reduced. It is better to work well.
[0007]
However, in the conventional cathode ray tube, the electron beam passes close to the inner surface near the neck side of the funnel on which the deflection yoke is mounted. Therefore, if the neck diameter and the outer diameter near the neck side of the funnel are further reduced, FIG. As shown to a), the electron beam 6 collides with the inner wall near the neck 3 side of the funnel 2, and the part 10 where the electron beam 6 does not reach is formed on the phosphor screen 4 as shown in FIG. Therefore, it is difficult to reduce the deflection power in the conventional cathode ray tube. If the electron beam 6 continues to collide with the inner wall of the funnel 2 near the neck 3 side, the temperature of the portion increases as the glass melts, and there is a risk of implosion.
[0008]
As a means for solving such a problem, Japanese Patent Publication No. 48-34349 discloses that when a rectangular raster is drawn on a phosphor screen, an electron beam passage region in the vicinity of the neck side of a funnel to which a deflection yoke is attached. 12 (a), the cathode ray tube 12 shown in FIG. 12 (a) has the deflection yoke as shown in FIGS. 12 (b) to (f). The vicinity of the neck 3 side of the funnel 2 to be mounted is shown in a shape that gradually changes from a circular shape to an elliptical shape in the direction of the panel 1 from the neck 3 side to an almost rectangular shape. When the shape near the neck side of the funnel to which the deflection yoke is attached is configured as described above, the diagonal where the electron beam easily collides with the case where the neck side of the funnel 2 is circular as shown in FIG. Increase the inner diameter (near the diagonal axis: near the D axis) to avoid collision of the electron beam, reduce the inner diameter near the long axis (horizontal axis: H axis) and the short axis (vertical axis: H axis), By making the horizontal and vertical deflection coils of the deflection yoke approach the electron beam passage region, the electron beam can be efficiently deflected, thereby reducing the deflection power.
[0009]
However, in such a cathode ray tube, as the vicinity of the neck side of the funnel to which the deflection yoke is attached is made closer to a rectangle, the pressure resistance strength decreases and the safety is impaired. Therefore, practically, the shape must be appropriately rounded, and the deflection power cannot be reduced sufficiently.
[0010]
[Problems to be solved by the invention]
As described above, in recent years, there has been a demand for reduction of the deflection power and leakage magnetic field of the cathode ray tube. However, this is performed while satisfying the high luminance and high frequency required for OA equipment such as HDTV and PC. It is extremely difficult. Conventionally, as a structure to reduce the deflection power, a structure in which the shape near the neck side of the funnel to which the deflection yoke is attached is changed from a circular shape to an elliptical shape from a circular shape to a panel direction from the neck side to a substantially rectangular shape has been proposed. Has been.
[0011]
However, if the vicinity of the neck side of the funnel is made close to a rectangle in this way, the pressure resistance strength is lowered and the safety is impaired. Therefore, practically, the shape must be appropriately rounded, and the deflection power cannot be reduced sufficiently. At that time, the simulation technology for setting the envelope shape of the cathode ray tube was undeveloped, and the current electron beam trajectory analysis and deflection magnetic field analysis could not be performed. It could not be designed to reduce the power and leakage magnetic field.
[0012]
The present invention has been made to solve the above problems, and an object of the present invention is to constitute a cathode ray tube capable of reducing deflection power and leakage magnetic field while satisfying high luminance and high frequency.
[0013]
[Means for Solving the Problems]
A cathode ray tube according to an aspect of the present application is:
Near the neck side of the funnel having a substantially rectangular panel, a funnel-like funnel connected to the panel, and a cylindrical neck connected to a small-diameter end of the funnel. A cathode ray tube that deflects an electron beam from an electron gun disposed in the neck in a major axis direction and a minor axis direction of the panel by a deflection magnetic field generated by a deflection yoke mounted on the outside of the panel;
The outer shape near the neck side of the funnel gradually changes from the neck side to the panel direction to a non-circular shape having a maximum diameter in directions other than the major axis and minor axis directions, and the radius of the maximum diameter is L When the difference between the maximum radius L and the long axis direction radius is ΔH, the difference between the maximum radius L and the short axis direction radius is ΔV, and the amount of addition of ΔH and ΔV is ΔHV, The value of ΔHV / L at the tube axis direction position where the panel side end is located is larger than the value of ΔHV / L at the tube axis direction position where the deflection magnetic field has a peak value, and
When ΔHV / L corresponding to the position in the tube axis direction is indicated by a ΔHV / L curve, the slope of the ΔHV / L curve at the position in the tube axis direction where the deflection magnetic field has a peak value is the position of the end of the deflection yoke on the panel side. It is characterized by being larger than the slope of the ΔHV / L curve at the tube axis direction position .
[0014]
Further, the outer shape near the neck side of the funnel is at the panel side end of the deflection yoke,
0.3 ≦ ΔHV / L ≦ 0.6
Formed in a relationship.
[0015]
Also, at the panel side end of the deflection yoke,
0.35 ≦ ΔHV / L ≦ 0.6
Formed in a relationship.
[0016]
Also, at the panel side end of the deflection yoke,
0.3 ≦ ΔHV / L ≦ 0.4
Formed in a relationship.
[0017]
In addition, the outer shape in the vicinity of the neck side of the funnel is formed so as to gradually change from the neck side in the panel direction to a substantially rectangular shape having a diagonal axis in a direction other than the major axis and minor axis directions.
[0018]
Further, when ΔHV corresponding to the position in the tube axis direction is indicated by a ΔHV curve, ΔHV gradually increases from the neck side to the panel direction, and the slope of the ΔHV curve at the position in the tube axis direction at the panel side end of the deflection yoke is 0. It was formed to be 6 to 1.1.
[0019]
The deflection coil is provided with a saddle type horizontal deflection coil, and the diameter of the crossover portion on the panel side of the horizontal deflection coil is formed in accordance with the outer diameter in the end axial direction in the vicinity of the neck side of the funnel.
[0020]
And a vacuum envelope comprising a substantially rectangular panel, a funnel-shaped funnel connected to the panel, and a cylindrical neck connected to the small-diameter end of the funnel. In the cathode ray tube that deflects the electron beam from the electron gun disposed in the neck in the major axis and minor axis directions of the panel by the magnetic field generated by the deflection yoke mounted on the outside near the side, near the neck side of the funnel From the neck side to the panel direction gradually changes from a circular shape to a non-circular shape having a maximum diameter in directions other than the major axis and minor axis directions, and the radius of the maximum diameter is L, and the maximum radius L and long When the difference from the axial radius is ΔH, the difference between the maximum radius L and the minor axis radius is ΔV, and the amount of addition of ΔH and ΔV is ΔHV, in the vicinity of the panel side end of the deflection yoke,
0.3 ≦ ΔHV / L ≦ 0.6
Formed in a relationship.
[0021]
In addition, the outer shape of the funnel near the neck side was formed into a substantially rectangular shape having a diagonal axis from a circle to a direction other than the major axis and minor axis direction gradually from the neck side to the panel direction.
[0022]
Further, ΔHV is gradually increased from the neck side toward the panel, and the increase rate of ΔHV in the vicinity of the panel side end of the deflection yoke is set to 0.6 to 1.1.
[0023]
DETAILED DESCRIPTION OF THE INVENTION
Embodiments of the present invention will be described below with reference to the drawings.
[0024]
FIG. 1 shows a color picture tube which is one form thereof. The color picture tube includes a substantially rectangular glass panel 20, a funnel-shaped glass funnel 21 described later connected to the panel 20, and a cylindrical glass connected to a small-diameter end of the funnel 21. A vacuum envelope 23 made of a neck 22 is provided. A phosphor screen is provided on the inner surface of the panel 20, and a shadow mask is disposed inside the panel 20 so as to face the phosphor screen. On the other hand, an electron gun is disposed in the neck 22. A deflection yoke (not shown) is mounted outside the vicinity 24 of the funnel 21 on the neck 22 side, and an electron beam emitted from an electron gun disposed in the neck 22 by a magnetic field generated by the deflection yoke is displayed on the panel. By deflecting in the major axis (horizontal axis: H axis) direction and the minor axis (vertical axis: V axis) direction of 20 and scanning the phosphor screen in the major axis and minor axis directions through a shadow mask, color is obtained. An image is displayed.
[0025]
In particular, in this color picture tube, the vicinity 24 on the neck 22 side of the funnel 21 to which the deflection yoke is mounted is gradually changed from a circular shape similar to the neck 22 in the direction from the neck 22 toward the panel 20, and the major axis and the minor axis of the panel 20 gradually. It is formed in a non-circular shape (rectangular shape) having a maximum diameter in a direction other than the direction.
[0026]
That is, as shown in FIG. 2A, the major axis direction outer diameter is indicated by a curve 25, the minor axis direction outer diameter is indicated by a curve 26, and the diagonal axis direction outer diameter is indicated by a curve 27. The outer diameters of the shaft, the minor axis, and the diagonal axis are the same circle, but as shown in FIG. 3, the major axis is larger than the outer diameter in the diagonal axis (D axis) as approaching the panel side. The outer diameter in the minor axis direction is gradually smaller and flattened into a non-circular shape (rectangular shape). The radius of the maximum outer diameter (diagonal axis direction outer diameter) is L, and the maximum radius L and the major axis direction radius The difference is ΔH, the difference between the maximum radius L and the minor axis direction radius is ΔV, and the sum (addition amount) of these ΔH and ΔV is ΔHV,
ΔHV = ΔH + ΔV
ΔHV changes as shown by a curve 28 in FIG. 2B, and ΔHV / L indicating the ratio of non-circularization (flattening) changes as shown by a curve 29 in FIG. It becomes the shape to do. And in the deflection yoke provided with the front end of the deflection yoke near the neck side of the funnel, for example, a saddle type horizontal deflection coil, the non- The circularization ratio ΔHV / L is 0.3 to 0.6, and 0.4 in the illustrated example.
[0027]
The shape near the neck side of the funnel to which the deflection yoke is attached is that the neck is made of cylindrical glass due to the configuration of the vacuum envelope, and the funnel is a shape that greatly expands from the neck side to the panel direction. For this reason, a rectangular shape that approximates the aspect ratio of the screen, for example, from the neck side cannot be achieved.
[0028]
FIG. 5 shows three typical examples of changes in the shape of the portion where the deflection yoke is mounted, that is, changes in ΔHV. A curve 30 is a case where ΔHV gradually increases from the neck side to the panel direction, and the increase rate (curve slope) of ΔHV at the panel side end is about 0.7. A curve 31 shows a case where the change at the intermediate portion is relatively small and becomes large near the panel side end portion, and the increase rate of ΔHV at the panel side end portion is 1.1 or more. On the other hand, the curve 32 shows a case where the change at the intermediate portion is relatively large, becomes small near the panel side end portion, and the increase rate of ΔHV at the panel side end portion is 0.6 or less. is there.
[0029]
Of these three examples, when the change in the middle part is large as shown by the curve 32, the mechanical strength tends to be insufficient, and practically ΔHV gradually increases from the neck side toward the panel. A desired funnel can be configured by setting the increase rate of ΔHV in the vicinity of the panel side end to 0.6 to 1.1.
[0030]
In this way, the vicinity of the neck side of the funnel to which the deflection yoke is mounted has a non-circular shape having a maximum diameter in a direction other than the major axis and minor axis of the panel from the circular side gradually toward the panel from the neck side, and the front end of the deflection yoke The ratio ΔHV / L between the maximum radius L indicating the ratio of non-circularization near the panel side end where the portion is located and the sum ΔHV of ΔH and ΔV,
0.3 ≦ ΔHV / L ≦ 0.6
Then, the deflection power can be reduced, and the leakage magnetic field can be reduced to a standard value or less indicated by the straight line 34 as shown by the curve 33 in FIG. Furthermore, by setting the rate of increase of ΔHV in the vicinity of the end portion on the panel side to be 0.6 to 1.1, it is possible to obtain a funnel having sufficient pressure resistance strength. Therefore, by configuring as described above, it is possible to obtain a color picture tube that can reduce the deflection power and the leakage magnetic field and has sufficient pressure resistance strength.
[0031]
The above results were obtained as a result of detailed magnetic field analysis of the deflection yoke mounted on the cathode ray tube.
[0032]
In other words, in order to reduce the deflection power of the cathode ray tube, it is necessary to make the vicinity of the neck side of the funnel to which the deflection yoke is mounted as compact as possible and to make the deflection coil small. It is necessary not to collide with the inner wall in the vicinity of the neck side. To that end, the outer diameter increases from the neck side to the panel side in accordance with the shape of the inner electron beam passage area, which is considered to have a shape that approximates the aspect ratio of the screen, near the neck side of the funnel. The cross-sectional shape perpendicular to the tube axis is a non-circular shape such as a substantially elliptical shape or a rectangular shape having a maximum diameter in a direction other than the major axis and minor axis directions of the panel, and the deflection coil has a shape suitable for this shape. It is desirable to do.
[0033]
In this case, generally, the intensity distribution of the deflection magnetic field generated by the deflection coil has a peak value near the center of the deflection coil as shown by a curve 36 in FIG. 7, while the vicinity of the neck side of the funnel to which the deflection yoke is attached. Since the outer diameter gradually decreases from the peak value to the neck side, in order to reduce the deflection power, it is effective to gradually decrease the outer diameter of the funnel as much as possible from the peak value to the neck side. However, since the deflection power is an integral value of the entire deflection magnetic field exerted on the electron beam, it is also important to reduce the outer diameter of the funnel from the peak value to the panel side.
[0034]
Also, the leakage magnetic field generated from the deflection yoke is mainly generated from the horizontal deflection coil, and since the front end of the deflection yoke is wide open in the panel direction, a strong magnetic field leaks in the panel direction, and the leakage magnetic field is far away. It extends to. Therefore, in order to reduce the leakage magnetic field from the deflection yoke, it is necessary to make the front end diameter of the deflection yoke as small as possible.
[0035]
That is, as shown in FIG. 8, for example, in a deflection yoke in which both the horizontal deflection coil 38 and the vertical deflection coil 39 are saddle type, in order to reduce the diameter of the crossover portion at the front end of the horizontal deflection coil 38, In order to reduce the outer diameter in the short axis direction of the vicinity 24 of the funnel neck where the crossover portion is located and to reduce the diameter of the crossover portion at the front end of the vertical deflection coil 39, the crossover portion is located. It is necessary to reduce the outer diameter in the major axis direction near the neck side 24 of the funnel.
[0036]
That is, in order to reduce the deflection power and the leakage magnetic field at the same time, it is necessary to make the vicinity of the neck side of the funnel to which the deflection yoke is attached as small as possible. However, according to the present inventors' magnetic field analysis and prototype experiment, for example, in a display tube used for a personal computer or a computer terminal, even if a 110-degree deflection tube is designed using a conventional funnel, the deflection power is sufficiently high. It was impossible to reduce it, and the leakage magnetic field was large, and the Swedish standard value could not be cleared.
[0037]
On the other hand, as described above, the vicinity of the neck side of the funnel to which the deflection yoke is attached is formed into a non-circular shape having a maximum diameter in a direction other than the major axis and minor axis direction of the panel gradually from the neck side to the panel direction. By reducing the radius in the major axis and minor axis direction relative to the maximum radius L, the difference ΔH between the maximum radius L and the major axis radius, the minor axis radius, An interesting result was obtained that the difference ΔV of both contributed equally. By setting the ratio ΔHV / L of the maximum radius L indicating the ratio of the non-circularization and the sum ΔHV of ΔH and ΔV to 0.3 or more, the deflection power and the leakage magnetic field can be practically used. It was found that it can be reduced.
[0038]
However, in this case, as a vacuum envelope component, it is necessary to avoid a decrease in mechanical strength and to have a shape that maintains sufficient pressure resistance strength. If the shape near the neck side of the funnel to which the deflection yoke is mounted is as shown in FIG. 9, for example, if the central portion of each side 41 of the substantially rectangular cross section is recessed inward, the side 41 Due to the atmospheric pressure load applied to the central portion, extremely large tension exceeding 1200 psi is applied to each diagonal portion, making it difficult to put it to practical use. For this reason, there is a limit to non-circularization near the neck side of the funnel to which the deflection yoke is mounted, and ΔHV / L is limited to 0.6 or less when the shape is the same as the aspect ratio of the screen. And the result was obtained.
[0039]
In the above embodiment, a color picture tube has been described. However, the present invention can also be applied to a cathode ray tube other than a color picture tube.
[0040]
【The invention's effect】
Near the neck side of the funnel having a substantially rectangular panel, a funnel-shaped funnel connected to the panel, and a cylindrical neck connected to the small-diameter end of the funnel. In a cathode ray tube apparatus in which a deflection yoke for generating a magnetic field for deflecting an electron beam emitted from an electron gun disposed in the neck in the long axis direction and the short axis direction of the panel is mounted on the outside of the neck side of the funnel In a cathode ray tube that deflects an electron beam from an electron gun disposed in the neck in the major axis and minor axis directions of the panel by a magnetic field generated by a deflection yoke mounted on the outside in the vicinity, The outer shape gradually changes from the neck side to the panel direction from a circular shape to a non-circular shape having a maximum diameter in directions other than the major axis and minor axis directions, and the radius of the maximum diameter is L, When the difference between the large radius L and the major axis radius is ΔH, the difference between the maximum radius L and the minor axis radius is ΔV, and the addition amount of these ΔH and ΔV is ΔHV, the panel side end of the deflection yoke In the vicinity
0.3 ≦ ΔHV / L ≦ 0.6
Furthermore, when the ΔHV is gradually increased from the neck side to the panel direction, and the increase rate of ΔHV in the vicinity of the panel side end of the deflection yoke is 0.6 to 1.1, the deflection yoke is It can be made compact, and the deflection power and the leakage magnetic field from the deflection yoke can be greatly reduced. Further, a wide deflection angle tube can be deflected at a practical deflection frequency, and a cathode ray tube that satisfies the standard with respect to a leakage magnetic field can be configured.
[Brief description of the drawings]
FIG. 1 is a diagram showing a configuration of a color picture tube which is an embodiment of the present invention.
FIG. 2 (a) is a diagram showing the shape of the vicinity of the neck side of the funnel to which the deflection yoke of the color picture tube is mounted, and FIG. 2 (b) is its maximum outer diameter, major axis and minor axis direction outer side. It is a figure which shows the change of the sum of the difference with a diameter.
FIG. 3 is a diagram for explaining a change in the major axis and minor axis direction outer diameters with respect to the maximum outer diameter in the vicinity of the neck side of the funnel to which the deflection yoke is mounted.
FIG. 4 is a diagram showing a non-circularization ratio in the vicinity of a neck side of a funnel to which the deflection yoke is attached.
FIG. 5 is a diagram for explaining a shape change in the vicinity of a neck side of a funnel to which the deflection yoke is attached.
FIG. 6 is a diagram showing the relationship between the ratio of non-circularization near the neck side of the funnel to which the deflection yoke is mounted and the leakage magnetic field.
FIG. 7 is a diagram showing an intensity distribution on a tube axis of a deflection magnetic field generated by a deflection coil.
FIG. 8 is a diagram showing a configuration of a deflection yoke.
FIG. 9 is a view for explaining the limit of non-circularization near the neck side of the funnel to which the deflection yoke is attached.
FIG. 10 is a diagram showing a configuration of a conventional color picture tube.
FIGS. 11 (a) and 11 (b) are diagrams for explaining collisions of electron beams that occur when the neck diameter and the diameter near the neck side of the funnel are reduced in a conventional color picture tube, respectively. is there.
FIGS. 12 (a) to 12 (f) are diagrams showing shapes near the neck side of a funnel to which a deflection yoke of a known color picture tube is mounted, respectively.
FIG. 13 is a diagram for explaining the relationship with the collision of electron beams when the vicinity of the neck side of the funnel to which the deflection yoke is attached is substantially rectangular.
[Explanation of symbols]
20 ... Panel 21 ... Funnel 22 ... Neck 23 ... Vacuum envelope 24 ... Near the neck side of the funnel 38 ... Horizontal deflection coil 39 ... Vertical deflection coil

Claims (8)

Near the neck side of the funnel having a substantially rectangular panel, a funnel-like funnel connected to the panel, and a cylindrical neck connected to a small-diameter end of the funnel. A cathode ray tube that deflects an electron beam from an electron gun disposed in the neck in a major axis direction and a minor axis direction of the panel by a deflection magnetic field generated by a deflection yoke mounted on the outside of the panel;
The outer shape near the neck side of the funnel gradually changes from the neck side to the panel direction to a non-circular shape having a maximum diameter in directions other than the major axis and minor axis directions, and the radius of the maximum diameter is L When the difference between the maximum radius L and the long axis direction radius is ΔH, the difference between the maximum radius L and the short axis direction radius is ΔV, and the amount of addition of ΔH and ΔV is ΔHV, The value of ΔHV / L at the tube axis direction position where the panel side end is located is larger than the value of ΔHV / L at the tube axis direction position where the deflection magnetic field has a peak value, and
When ΔHV / L corresponding to the position in the tube axis direction is indicated by a ΔHV / L curve, the slope of the ΔHV / L curve at the tube axis direction position where the deflection magnetic field has a peak value is the position of the end of the deflection yoke on the panel side. A cathode ray tube characterized by being larger than the slope of the ΔHV / L curve at the tube axis direction position . At the panel side end of the deflection yoke, the outer shape near the neck side of the funnel is
0.3 ≦ ΔHV / L ≦ 0.6
The cathode ray tube according to claim 1, wherein the cathode ray tube is formed in the relationship of At the panel side end of the deflection yoke,
0.35 ≦ ΔHV / L ≦ 0.6
The cathode ray tube according to claim 1, wherein the cathode ray tube is formed in the relationship of At the panel side end of the deflection yoke,
0.3 ≦ ΔHV / L ≦ 0.4
The cathode ray tube according to claim 1, wherein the cathode ray tube is formed in the relationship of   The outer shape of the funnel in the vicinity of the neck side gradually changes from the neck side to the panel direction in a substantially rectangular shape having a diagonal axis in a direction other than the major axis and minor axis directions. Cathode ray tube.   When ΔHV corresponding to the position in the tube axis direction is indicated by a ΔHV curve, ΔHV gradually increases from the neck side to the panel direction, and the slope of the ΔHV curve at the tube axis direction position at the panel side end of the deflection yoke is 0.6 to 5. The cathode ray tube according to claim 1, wherein the cathode ray tube is 1.1.   2. The deflection coil according to claim 1, wherein the deflection coil includes a saddle-type horizontal deflection coil, and the diameter of the crossover portion on the panel side of the horizontal deflection coil is matched with the outer diameter in the end axial direction near the neck side of the funnel. The cathode ray tube according to 1. Near the neck side of the funnel having a substantially rectangular panel, a funnel-like funnel connected to the panel, and a cylindrical neck connected to a small-diameter end of the funnel. A cathode ray tube that deflects an electron beam from an electron gun disposed in the neck in a major axis direction and a minor axis direction of the panel by a deflection magnetic field generated by a deflection yoke mounted on the outside of the panel;
The outer shape near the neck side of the funnel gradually changes from the neck side to the panel direction to a non-circular shape having a maximum diameter in directions other than the major axis and minor axis directions, and the radius of the maximum diameter is L When the difference between the maximum radius L and the long axis direction radius is ΔH, the difference between the maximum radius L and the short axis direction radius is ΔV, and the amount of addition of ΔH and ΔV is ΔHV, At the panel end,
In the above funnel, when ΔHV / L corresponding to the position in the tube axis direction is indicated by a ΔHV / L curve, ΔHV / L monotonously increases from the position in the tube axis direction where the deflection magnetic field has a peak value toward the panel side end. A cathode ray tube having a shape that changes so that the slope of the ΔHV / L curve gradually decreases.

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