KR100494162B1 - Panel Structure of Plane CRT - Google Patents

Abstract

The present invention relates to a cathode ray tube, in particular to a structure that increases the thickness in the vertical axis direction of the panel most susceptible to vacuum stress structure to solve the degradation of the panel, increase in panel weight, panel breakage due to heat treatment process in the cathode ray tube manufacturing process The present invention relates to a panel structure for flat cathode ray tubes, which enables slimming and high definition of cathode ray tubes.

The panel structure for a planar cathode ray tube according to the present invention has an outer surface of a panel bonded to the front of the funnel to form a vacuum container, and the inner surface is curvature in a convex direction with respect to the tube axis. In the panel is provided with a grill or an open bridge mask facing the phosphor screen, the mask is a flat cathode ray tube having a curvature radius of infinity in the vertical direction is infinite,

The radius of curvature of the horizontal axis of the effective surface of the panel is referred to as Rh, the radius of curvature of the vertical axis is referred to as Rv, the radius of curvature of the diagonal axis is referred to as Rd, the thickness of the central portion of the panel is referred to as Tc, and the thickness of the horizontal end of the effective plane is Is Th, the thickness of the vertical end is Tv, and the thickness of the diagonal end is Td, the thickness structure of the panel satisfies the relationship of Tv / Tc <Td / Tc <Th / Tc, The structure is characterized by satisfying the relation of Rh < Rv < Rd.

Description

Panel Structure for Planar Cathode Ray Tubes

The present invention relates to a cathode ray tube, in particular, to a structure that increases the thickness in the vertical axis direction of the panel most susceptible to vacuum stress structure to reduce the brightness due to light transmittance of the panel, increase the panel weight, heat treatment in the manufacturing process of the cathode ray tube The present invention relates to a panel structure for a flat cathode ray tube, which can solve panel damage caused by a process and enable slimming and high definition of a cathode ray tube.

1 is a cross-sectional view showing a structure of a general planar cathode ray tube, in which a general planar cathode ray tube as shown in the drawing includes a rectangular panel 3 positioned at the front and a funnel 2 positioned at the rear of the panel 3. ) And a vacuum container 1 including a neck 4 extending at the rear end of the funnel 2.

The inside of the vacuum vessel 1 is maintained at a high vacuum of about {10} ^ {-7} Torr for smooth flight of electrons.

Also inside the neck 4 is an electron gun 6 which emits R, G, B electron beams 5.

In addition, phosphors of three colors (R, G, and B) are coated on the inner surface of the panel 3 to form a screen 7, and a tension mask for color screening facing the screen 7. (8) is formed, and the tension mask (8) is stretched and fixed in the vertical axis direction of the cathode ray tube by a frame (9).

In addition, the electron beam 5 emitted from the electron gun 6 is deflected by the deflecting device 13 formed outside the funnel 2 to properly irradiate the phosphor screen 7 to realize an image.

2 is a perspective view illustrating an assembly structure of a conventional tension mask and a frame.

In the assembly of the tension mask 8 and the frame 9 as shown in the drawing, both ends of the long side of the tension mask 8 having the grille or stripe-shaped electron beam transmission holes 10 are formed on the frame 9. Welding is fixed. At this time, the tension mask 8 is subjected to a tensile force in the vertical direction by the compression reaction force of the frame (9).

The curvature in the vertical direction of the tension mask 8 is straight, and in the horizontal direction, a predetermined radius of curvature Rm is formed in the convex direction with respect to the tube axis, similar to the inner curvature of the panel 3.

In addition, the electron beam transmitting holes 10 formed on the tension mask 8 are arranged at extremely minute intervals in the vertical direction to form a straight group. The group is formed repeatedly in accordance with a constant pitch Ph again in the horizontal direction.

Meanwhile, the inside of the cathode ray tube is maintained in a vacuum for smooth flight of the electron beam 5, and the panel 3 forming the front surface of the vacuum vessel 1 will be described in detail with reference to the accompanying drawings below.

3 is a plan view and a cross-sectional view showing a conventional panel structure. As shown in the drawing, the conventional panel 3 includes an effective surface portion 14 on which a phosphor screen is formed, and a long side portion formed in a horizontal direction at both ends of a vertical axis. 15, a short side portion 16 formed in the vertical direction at both ends of the horizontal axis, and a corner portion 17 forming both ends of the diagonal axis.

The three portions (long side portion, short side portion, and corner portion) are each formed with a skirt portion 18 having a shape bent rearward of the tube axis at the edge of the effective surface portion 14.

4 is a cross-sectional view showing a vertical, horizontal, diagonal cross section of a conventional flat panel in one place.

As shown in the figure, first, the curvature radii of the horizontal axis, the vertical axis and the diagonal axis of the inner surface of the panel are called Rh, Rv, and Rd, respectively, and the thickness of the center portion of the panel is called Tc, When the thicknesses of the diagonal ends are Th, Tv, and Td, respectively, the radius of curvature of the inner surface of the formed mask type cathode ray tube satisfies the relation of Rh > Rd > The panel thickness structure of the type cathode ray tube satisfies the relation of Tv / Tc <Th / Tc <Td / Tc, and the inner radius of curvature is Rv> Rd> Rh or Rv ≒ Rd> Rh or Rd> Rv or Rh Configured to satisfy.

On the other hand, the amount of wedges (ratio of the thickness Td of the diagonal end portion, that is, Td / Tc) on the basis of the center thickness Tc is usually about 1.3.

The crystal background of the inner surface curvature R of the panel 3 of the conventional mask stretching type planar cathode ray tube having the above configuration will be described in more detail with reference to the accompanying drawings below.

5 (a) and 5 (b) are schematic diagrams showing the geometrical relationship between a panel, a mask, and an electron beam for a foamed mask type planar cathode ray tube and a mask stretched planar cathode ray tube, respectively.

First, the foamed mask type cathode ray tube of (a) will be described. After the electron beam 5 reaches the inner surface of the panel 3 through the electron beam transmission hole of the foamed mask 19, the adjacent electron beam 5 and In order to be able to maintain the value of 1 which is the optimal state, the beam array GR indicating the degree of uniformly spaced intervals of the panel surface curvature R, the form mask curvature Rm, and the electron beam 5 The following geometrical relationship must be established.

here,

GR: beam arrangement between adjacent electron beams,

S: distance between the center electron beam and the surrounding electron beam located on the deflection center (DC),

Q: the distance between the mask and the inner surface of the panel on the electron beam path,

Ph: distance between the transmission hole and the adjacent transmission hole at the position where the electron beam reached,

L: The linear distance between the center of deflection at the position where the electron beam reached and the inner surface of the panel.

In the above relation, when the electron beam 5 is irradiated to the center of the panel 3, Lo (distance from the center of the panel) <L (panel) due to the increase in L value as the electron beam 5 is irradiated in the peripheral direction. Distance from the periphery).

In order to maintain the value of GR = 1 according to the above change, the Q value should be increased toward the periphery. In other words, a relationship of Qo (distance at the center of the panel) < Q '(distance at the panel periphery) is required.

On the other hand, in the conventional form-type flat cathode ray tube, the required Q value increase in the periphery is modified by changing the shape of the mask to take a corresponding structure.

Therefore, when determining the inner curvature of the panel, it is designed considering only the image floating effect according to the panel thickness and mechanical strength in vacuum, and the vertical, horizontal, and diagonal curvature radii of the inner surface of the panel are generally applied to the vacuum and stress structure of the panel. It was produced in the form of advantageous Rd> Rh> Rv.

As shown in (b) of FIG. 5, in the mask-stretched planar cathode ray tube, the color selection mask is a tension mask 8 in which the color is stretched in the vertical direction. The Q value of the viewing direction is in the form of Qo (center)> Q '(around 6, 12 o'clock) as opposed to a formed mask type planar cathode ray tube. The value will be less than 1.

In the tension mask 8, the curvature in the vertical direction is close to infinity (straight line), so that the vertical curvature radius Rv of the inner surface of the panel shown in FIG. 4 is maintained to be the horizontal curvature radius Rh and the diagonal curvature radius Rd. It should be made larger.

That is, the radius of curvature of the inner surface of the conventional mask-stretched planar cathode ray tube as described above is increased by increasing the vertical radius of curvature Rv in a more flat direction, where Rv> Rd> Rh or Rv ≒ Rd> Rh or Rd > Rv or Rh is satisfied, and the panel thickness structure satisfies Tv / Tc < Th / Tc < Td / Tc.

However, in order to achieve the slimming (cathode ray tube having a length of 15% or more compared to the reference cathode ray tube) or the high definition (mask pitch of 0.5 mm or less), the form-type mask or tension mask-type cathode ray tube described above has various problems. .

First, in the case of a form mask type cathode ray tube, when the mask pitch is set to 0.5 mm or less, a problem occurs in strength, which causes a problem of being very vulnerable to external vibration.

In the case of the stretching type cathode ray tube, the diagonal deflection angle is increased by 120 degrees due to slimming, and the value of Lo / L becomes smaller.

Therefore, in order to maintain the condition of GR = 1, the Q value should be increased toward the diagonal of the effective surface, so that the panel thickness structure is Tv / Tc < Th / Tc < Td / Tc, or the curvature radius structure on each axis is If Rv> Rd> Rh or Rv ≒ Rd> Rh or Rd> Rv or Rh, the GR value required for optimally maintaining the screen quality, i.e., GR = 1 ± 0.03, cannot be satisfied. .

When the conventional inner surface curvature structure is applied to the slim type cathode ray tube, the GR value is about 0.80 or less, and the image deteriorates to such an extent that basic image display of the cathode ray tube cannot be performed.

 In addition, another important factor to be considered in determining the inner surface curvature of the cathode ray tube is the vacuum stress received by the panel portion during vacuum evacuation of the cathode ray tube.

The vacuum stress generated in the panel unit will be described in more detail with reference to the accompanying drawings as follows.

6 is a cross-sectional view showing a stress structure of a CRT tube after a conventional vacuum exhaust.

As shown in the figure, a vacuum vessel 1 formed of a panel and a funnel is formed, and in the case of evacuating the interior thereof, a particularly strong tensile stress is generated in the panel portion 3 to deform the vacuum vessel 1. Will be raised.

In the vacuum evacuation as described above, the panel effective surface portion 14 is deformed inwardly with the center of the panel 3 as the apex, and the panel scud portion 18 is deformed outwardly.

In particular, a strong tensile stress is generated in the effective surface portion 14 of the panel, the maximum tensile stress generating portion is the maximum stress is generated at the vertical end (Ev) of the panel effective surface.

However, in order to satisfy the condition of GR = 1 for slimming the cathode ray tube, in designing the panel inner curvature, the effective surface horizontal axis end Q value is further increased, and accordingly, the vacuum stress is also increased.

At this time, if the inner surface thickness structure of the panel is made to satisfy the conditions of Tv / Tc <Th / Tc <Td / Tc, it can not effectively cope with the vacuum stress as described above, causing serious safety problems due to deterioration of explosion-proof characteristics Let's do it.

For example, in the case of a 30V type mask stretch type planar cathode ray tube, tensile stress is generated at about 12 Mpa or more, exceeding the allowable limit tensile stress of 10 MPa.

In order to solve this problem, conventionally, as shown in (b) of FIG. 5, the panel outer surface is increased by a predetermined thickness (a) to suppress the generation of stress in the effective surface portion.

However, such an increase in the thickness of the panel 3 has a problem that the light transmittance is lowered and the brightness characteristics are deteriorated, and the breakage rate is increased during the heat treatment process in the manufacturing process of the cathode ray tube.

In addition, due to this, not only the thermal process index is lowered, but also the material cost and production cost increase due to the increase in panel weight.

The present invention has been proposed to solve the above problems, an object of the present invention is to solve the problem of breakage of the panel during the heat treatment process in the manufacturing process of the cathode ray tube and thereby lowered production speed, increase in weight and explosion-proof It is an object of the present invention to provide a panel structure for flat cathode ray tubes that can solve the problem.

In addition, while improving the strength of the vertical periphery, the most vulnerable part of the panel in the vertical direction, it is possible to improve the brightness of the cathode ray tube by reducing the weight of the panel and the thickness of the panel, and to further refine and slim the CRT. Another object is to provide a panel structure for a flat cathode ray tube.

The panel structure for a flat cathode ray tube according to the present invention for achieving the above object, the outer surface of the panel which is bonded to the front of the funnel to form a vacuum container is composed of a substantially flat surface, the inner surface of the effective surface portion is formed a phosphor screen In a flat cathode ray tube having a curvature in the convex direction with respect to the tube axis, the inside of the panel is provided with a grill or open bridge mask facing the phosphor screen, the mask has an infinite radius of curvature stretched outward in the vertical direction,

The radius of curvature of the horizontal axis of the effective surface of the panel is referred to as Rh, the radius of curvature of the vertical axis is referred to as Rv, the radius of curvature of the diagonal axis is referred to as Rd, the thickness of the central portion of the panel is referred to as Tc, and the thickness of the horizontal end of the effective plane is Is Th, the thickness of the vertical end is Tv, and the thickness of the diagonal end is Td, the thickness structure of the panel satisfies the relationship of Tv / Tc <Td / Tc <Th / Tc, The structure is characterized by satisfying the relation of Rh < Rv < Rd.

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

Prior to the description of the drawings, the configuration of the mask stretching type flat cathode ray tube to which the present invention is applied is the same as that of a general color cathode ray tube except for the structure of the panel, and thus only the structure of the panel is omitted in FIGS. 7 and 8. Shown.

7 is a perspective view showing an effective surface portion of a flat panel according to the present invention, Figure 8 is a cross-sectional view showing a vertical, horizontal, diagonal cross-section of the flat panel of the present invention in one place.

As shown in the figure, the planar panel according to the present invention is formed such that the outer surface radius of curvature Ro of the effective surface portion 114 of the panel 103 is substantially planar.

The outer radius of curvature Ro may be expressed as three representative curvatures on horizontal, vertical, and diagonal axes.

In other words, the radius of curvature of the outer surface on the horizontal axis (H), the radius of curvature of the outer surface on the vertical axis (V), and the radius of curvature of the surface on the diagonal axis (D), each having the same shape of curvature. Or, each has a different radius of curvature, in the case of a single curvature form, the outer radius of curvature (Ro) value is about 30000 ~ 100000mm.

The inner surface curvature Ri of the panel 103 on which the phosphor screen is formed is represented by three representative curvatures on the horizontal, vertical, and diagonal axes in the same manner as the outer curvature radius Ro described above.

That is, the inner radius of curvature Rh on the horizontal axis H, the inner radius of curvature Rv on the vertical axis V, and the inner radius of curvature Rd on the diagonal axis D.

The outer curvature Ro and the inner curvature Ri of the panel 103 are separated by a distance Tc at the center of the panel 103, and the effective end surface 114 of the panel 103 has a diagonal end thickness. Denotes Td, the effective surface 114 vertical end thickness is Tv, the effective surface 114 horizontal end thickness is Th, and the thickness at the central portion is Tc. Since the curvature has a convex shape in Z), the Tv, Th, and Td are configured to have a value larger than the center thickness Tc of the panel 103.

In addition, the relationship between Tv, Tc, Td, and Th in the present invention satisfies the condition of Tv / Tc <Td / Tc <Th / Tc, and the inner radius of curvature satisfies the relationship of Rh <Rv <Rd. It is configured to.

The relationship between the representative inner surface curvature radii Rv, Rh, and Rd of each axis is as follows.

First, between Rv and Rh, it is configured to satisfy the condition of 0.5 < 3Rv / 2Rh < 2.7.

And, between Rd and Rv, it is configured to satisfy the condition of 1.06 <3Rd / 2Rv <1.2.

Further, between Rd and Rh, it is configured to satisfy the condition of 1.0 <3Rd / 2Rh <2.0.

 In addition, the thickness configuration of the vertical, horizontal, and diagonal ends of the effective surface 114 of the panel 103 will be described below.

First, the relationship between the center thickness Tc of the panel 103 and the diagonal end thickness Td of the effective surface 114 is configured to satisfy the condition of 1.0 <Td / Tc <1.5.

The relationship between the center thickness Tc of the panel 103 and the horizontal end thickness Th of the effective surface 114 is configured to satisfy the condition 1.27 <Th / Tc <1.35.

In addition, the relationship between the diagonal thickness Td of the effective surface 114 of the panel 103 and the vertical thickness Tv of the effective surface 114 is configured to satisfy the condition of 0.8 <Tv / Td <0.86.

Finally, the relationship between the horizontal end thickness Th of the effective surface 114 of the panel 103 and the vertical end thickness Tv is configured to satisfy the condition of 0.98 <Th / Td <1.04.

Hereinafter, the geometric meaning and the background of the radius of curvature of the panel structure for the mask-stretched planar cathode ray tube of the present invention configured as described above will be described.

First, structurally, the mask stretch type planar cathode ray tube exhibits the largest difference in comparison with the form masked cathode ray tube because the radius of curvature of the mask in the vertical direction is infinite, and as a result, the panel ( The thickness ratio between the center thickness Tc and the panel effective surface peripheral thickness Td or Tv of 103) is about 1.3, which is much smaller than around 2.0 of the form mask type.

This difference in thickness ratio is used for the conventional foam mask to reduce the vertical inner curvature of the panel 103 in order to reduce the electron beam arrangement difference between the center portion of the panel 103 and the vertical periphery of the panel 103 (points 6 and 12 o'clock). The result is an increase (planarization) than the panel.

However, there is a problem that the vertical periphery is very weakly dynamic in designing the panel of the mask stretch type planar cathode ray tube as described above.

In addition, as a countermeasure for high-definition and slimmer flat cathode ray tubes, simply increasing the glass thickness (Tc) as in the past increases the total weight of the cathode ray tubes, and breaks the glass during thermal processing. Will cause problems.

Accordingly, the present invention sets the vertical, horizontal and diagonal radius of curvature of the inner surface of the panel so as to secure the dynamic stress characteristics of the panel 103 within a range corresponding to the required beam arrangement, Set the horizontal and diagonal thickness.

9 is a schematic view showing the geometric relationship between the mask, the planar cathode ray tube and the mask, the electron beam according to the present invention, the tube axis (Z) in the upper direction of the deflection in the vertical direction with respect to the tube axis (Z), The lower part shows deflection in the horizontal direction.

 As shown in the figure, first, when the electron beam 105 is irradiated toward the center portion of the panel 103, the distance between the center electron beam (or the vertical peripheral electron beam) at the deflection center DC of the deflecting device and the surrounding electron beam is determined by So ( Or Sy), and the distance from the deflection center DC to the center of the inner surface of the panel 103 (or around the panel vertical direction) is Lo (or Ly), and the tension mask at the center of the panel 103 (or around the panel vertical direction). When the distance between the holes 108 is Qo (or Qy), and the pitch between the penetrating holes of the tension mask 108 and the adjacent penetrating holes is Ph, the center portion of the panel (or panel vertical) is passed through the tension mask 108. The beam array GR (or GRy) of the electron beam that has reached the periphery of the direction is satisfied to satisfy the following relationship.

,

According to the above relation, the distance L from the deflection center DC to the panel 103 is such that the distance Lo of the center reference and the distance Ly of the vertical reference around the center satisfy the condition of Lo <Ly.

Therefore, in order for the beam arrays GR and GRy to be 1, the distance between the panel 103 and the tension mask 108 is preferably in the form of Qo < Qy, but the vertical axis radius of curvature Rv of the inner surface of the panel 103 of the present invention is conventional. Because of its large proportion to the radius of curvature of the form-masked panels of the panel, the Qy value at the periphery of the vertical axis is smaller than that of Qo.

In this case, the beam array GRy is less than 1, and as a compensation method, the Sy value at the deflection center DC is larger than So when the deflecting device deflects the vertical periphery.

Such a deflecting device is capable of making the magnetic field inside the deflecting device into a barrel type magnetic field as compared with the conventional one, and the Sy value can be expanded to about 10% compared to the conventional one due to the development of the current deflecting device technology.

In this case, the S-value increased by about 10% by the deflector compensates for the Q-value increase Qy-Qo of the molecular term with respect to the increase Ly-Lo around the center of the L-value of the denominator in the relation. As a whole, the GRy value at the periphery of the panel vertical direction is kept equal to the GR value at the center portion.

Theoretically, the S value increase of 10% has a Q value reduction effect of 10%. Accordingly, it is possible to make the inner surface of the panel 103 curvature to the tension mask 108 by a 10% Q value decrease. .

Therefore, when determining the vertical radius of curvature Ry of the inner surface of the panel 103, the light source floating effect according to the mechanical stress and the refractive index of the glass, as well as the increase of the S value at the periphery of the vertical direction of the panel by the deflector should be determined. There is a need.

In addition, when the CRT becomes thinner, the Lo value decreases, so that the horizontal inner curvature of the panel 103 must be smaller than a specific ratio compared to the vertical inner curvature in order to maintain the GRx value equal to the center GR value. .

Therefore, in the present invention, the inner curvature value on each axis satisfies the condition of Rh <Rv <Rd, and the relationship between each Rh, Rv, Rd is 0.5 <3Rv / 2Rh <2.7 or 1.06 <3Rd / 2Rv < 1.2 and 1.0 <3Rd / 2Rh <2.0.

In addition, the CRT employing the stretching mask according to the present invention has a smaller vacuum in the vertical and horizontal ends of the effective surface portion 114 of the panel 103 than the conventional CRT employing the foamed mask. At the end of time, the stress is concentrated at the ends of the vertical and horizontal axes (especially the CRT on 16: 9).

In order to disperse the stress concentration, the panel thickness at the end of the horizontal axis must be increased.

Accordingly, in the present invention, when the thickness of the center portion of the panel 103 is referred to as Tc, and the thicknesses of the horizontal, vertical, and diagonal ends of the effective surface 114 are referred to as Th, Tv, and Td, respectively, Tv / Tc <Td / Tc <Th Configure to satisfy the condition of / Tc.

In addition, the ratio of the effective thickness of each axial direction with respect to the center thickness of the panel 103 is 1.0 <Td / Tc <1.5 or 1.27 <Th / Tc <1.35, 0.8 <Tv / Td <0.86, 0.98 <Th / Td <1.04 It is configured to satisfy the conditions of.

Looking at the contrast between the present invention and the prior art as described above through Table 1 and Table 2.

division Rv, Rd, Rh Relationship Rv Rh Rd The present invention Rh <Rv <Rd 11506 9149 12040 Prior art Rh <Rd <Rv 21425 10950 14858

Table 1 is a comparison table comparing the curvature of the inner surface of the panel with the prior art. In the present invention, the diagonal curvature radius Rd is larger than the vertical curvature radius Rv.

division Tv / Td Th / Td Tv / Tc Th / Tc Td / Tc The present invention 0.9 0.95 1.06 1.31 1.25 Prior art 0.83 1.01 1.04 1.25 1.24

Table 2 is a comparison table comparing the thickness of each axis of the conventional panel effective surface of the present invention.

The present invention has the effect that the mask stretch type cathode ray tube can provide the inner surface curvature advantageous for high definition.

In the case of the 32-inch CRT tube, when the overall length is reduced by 105 mm, the GR value can be satisfied in the range of 1 ± 0.03, so that the CRT tube can be made large and slim.

In addition, the thickness of the panel, that is, the center thickness Tc of the panel and the effective surface vertical, horizontal, and diagonal end thicknesses Tv, Th, and Td can be reduced.

In addition, due to the reduced panel thickness, it is possible to reduce the weight, which is the weakest point of the cathode ray tube, especially the planar cathode ray tube.

In addition, by reducing the thickness of the panel, the temperature difference between the center portion and the surface portion of the panel or the outer surface and the inner surface of the cathode ray tube container is reduced, so that the cathode ray tube including the panel during the heat treatment process up to about 450 ° C in the cathode ray tube manufacturing process. It is possible to lower the breakage rate of the container, and to increase the light transmittance according to the reduction of the panel thickness, thereby increasing the luminance.

1 is a cross-sectional view showing the structure of a general planar cathode ray tube.

Figure 2 is a perspective view showing an assembly structure of a conventional tension mask and the frame.

3 is a plan view and a cross-sectional view showing a conventional panel structure.

Figure 4 is a cross-sectional view showing a vertical, horizontal, diagonal cross section of a conventional flat panel in one place.

Figure 5 (a) and (b) is a schematic diagram showing the geometrical relationship between the panel, mask and electron beam of the conventional form-masked and mask-stretched planar cathode ray tube, respectively.

6 is a cross-sectional view showing a stress structure of a CRT tube after a conventional vacuum exhaust.

7 is a perspective view showing an effective surface portion of a flat panel according to the present invention.

Figure 8 is a cross-sectional view showing the vertical, horizontal, diagonal cross-section of the flat panel of the present invention in one place.

Figure 9 is a schematic diagram showing the geometrical relationship between the mask, the electron beam and the mask of the mask stretch type planar cathode ray tube according to the present invention.

* Description of the symbols for the main parts of the drawings *

1: vacuum vessel 2: funnel

3: panel 4: neck

5: electron beam 6: electron gun

7: Screen 8: Tension Mask

9: frame 10: electron beam transmission hole

13: deflection device 14: effective surface part

15: Long side 16: Short side

17: corner 18: skirt

103 panel 114: effective surface portion

105: electron beam

Claims (10)

The outer surface of the panel, which is bonded to the front of the funnel to form a vacuum container, is formed in a flat surface, and the inner surface of the panel has a curvature in the convex direction with respect to the tube axis, and the effective surface portion on which the phosphor screen is formed is opposed to the phosphor screen. In the flat cathode ray tube having a grill or open bridge type tension mask, the mask has an infinite radius of curvature stretched outward in the vertical direction,  Horizontal axis radius of curvature Rh of the inner surface of the effective surface of the panel, vertical radius of curvature Rv, radius of curvature Rd of the diagonal axis, thickness Tc of the central portion of the panel, thickness Th of the vertical edge of the effective surface, thickness Tv of the vertical edge, thickness of the diagonal end The following conditions for Td; Tv / Tc <Td / Tc <Th / Tc and Rh <Rv <Rd Flat cathode ray tube panel structure characterized in that to satisfy at the same time. The panel structure according to claim 1, wherein Tv / Tc < Td / Tc < Th / Tc and Rh < Rv < Rd, and Rv, Rh is 0.5 < 3 Rv / 2 Rh < 2.7. . 2. The panel structure according to claim 1, wherein Tv / Tc < Td / Tc < Th / Tc and Rh < Rv < Rd, and Rd and Rv are 1.06 < 3 Rd / 2 Rv < 1.2. . The panel structure according to claim 1, wherein Tv / Tc < Td / Tc < Th / Tc and Rh < Rv < Rd, and Rd and Rh are 1.0 < 3 Rd / 2 Rh < 2.0. . The panel structure according to claim 1, wherein the Td / Tc satisfying the Tv / Tc < Td / Tc < Th / Tc and Rh < Rv < Rd, and the Td, Tc is 1.0 < Td / Tc < 1.5. . The panel structure according to claim 1, wherein the Tv / Tc < Td / Tc < Th / Tc and Rh < Rv < Rd and the Th, Tc are 1.27 < Th / Tc < 1.35 . The panel structure according to claim 1, wherein Tv / Tc < Td / Tc < Th / Tc and Rh < Rv < Rd, and Tv, Td is 0.8 < Tv / Td < 0.86. . The panel structure according to claim 1, wherein the Tv / Tc < Td / Tc < Th / Tc and Rh < Rv < Rd and the Th, Td are 0.98 < Th / Td < 1.04 . The effective surface diagonal axis distance Sd and Tc of the panel, while satisfying Tv / Tc < Td / Tc < Th / Tc and Rh < Rv < Rd, wherein Sd / Tc < 45 Panel structure for flat cathode ray tube. The effective surface of claim 1, wherein the point having the smallest thickness of the panel on the vertical axis that satisfies the Tv / Tc < Td / Tc < Th / Tc and Rh < Rv < A panel structure for a flat cathode ray tube, characterized in that it exists between a diagonal end and a horizontal axis end.