KR950014601B1 - Crt device - Google Patents

Abstract

No content.

Description

Cathode ray tube device

1 is a view for explaining the configuration of a cathode ray tube apparatus according to a first embodiment of the present invention.

2 is a view for explaining the configuration of a cathode ray tube apparatus according to a first embodiment of the present invention.

3 is a block diagram of a cathode ray tube apparatus according to a first embodiment of the present invention.

4 is a view for explaining the configuration of a conventional cathode ray tube device.

5 is a configuration diagram of a conventional cathode ray tube device.

6 is a configuration diagram of a deflection yoke used in a conventional cathode ray tube apparatus.

7 is a configuration diagram of a cathode ray tube apparatus according to a second embodiment of the present invention.

8 is a view for explaining a cathode ray tube apparatus according to a third embodiment of the present invention.

9 is a view for explaining a cathode ray tube apparatus according to a third embodiment of the present invention.

10 is a configuration diagram of a cathode ray tube device according to a third embodiment of the present invention.

11 is a configuration diagram of a deflection yoke of a cathode ray tube apparatus according to a fourth embodiment of the present invention.

12 is a configuration diagram of a deflection yoke of a cathode ray tube device according to a fifth embodiment of the present invention.

13 is a view for explaining a cathode ray tube apparatus according to a fifth embodiment of the present invention.

14 is a view for explaining a cathode ray tube apparatus according to a sixth embodiment of the present invention.

15 is a view for explaining the cathode ray tube apparatus according to a sixth embodiment of the present invention.

16 is a block diagram of a cathode ray tube apparatus according to a sixth embodiment of the present invention.

17 is a block diagram of a cathode ray tube apparatus according to a seventh embodiment of the present invention.

18 is a block diagram of a cathode ray tube apparatus according to an eighth embodiment of the present invention.

* Explanation of symbols for main parts of the drawings

1: Funnel 1a: Neck

1b: cone part 1c: funnel body part

1d: Positive button 1e: Net seal line

2: panel 3: electron gun

4: explosion-proof band 5: silicone resin film

6: conductive film 7: deflection yoke

7a: horizontal deflection coil 7b: vertical deflection coil

7c: main part of the deflection yoke 7d: maximum diameter of the horizontal coil of the deflection yoke

8: conductive film for electric shield 12: conductive film

13: conductive tape 10: conductive button

11: funnel-shaped insulator 11a: graphite film

12: insulation film 13: an electrically conductive film

14: conductive tape 15: funnel-shaped insulator

16: conductive film 17: electric shield for electric field shield

18: conduction tape 19: funnel-shaped insulator

20: glass valve 21: transparent conductive film

22: insulating sheet having heat shrinkability 28: tube shaft

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a cathode ray tube device, and more particularly, to a reduction in an alternating electric field radiated by the deflection yoke.

4 is a conventional cathode ray tube configuration diagram. In the figure, the funnel part 1 is comprised from the funnel main body part 1c which has the neck part 1a, the cone part 1b, and the high voltage | pressure positive electrode button 1d, and is fret-sealed by the panel part 2. As shown in FIG. (1e) is a connection line between the neck portion 1a and the cone portion 1b, which is called a neck seal line, and has a slightly thinner glass thickness and a weaker portion than other portions having different strengths. The glass valve 20 is comprised as mentioned above. Further, the electron gun 3 is sealed in the neck portion 1a. An explosion-proof band 4 is wound around the side of the panel 2 to ensure explosion-proof characteristics, and four corners are integrally fitted with a stopper portion 4a for laying the glass valve 20 over a box (not shown). As an enemy. In addition, a silicon resin film 5 for insulation is formed around the high voltage positive electrode button 1d provided with the funnel main body portion 1c. In addition, a conductive film 6 for adding a capacitance to the cathode ray tube is formed on the outer surface of the funnel body portion 1c. This conductive film 6 is usually formed by applying graphite. Reference numeral 28 denotes a straight line parallel to the neck 1a, and represents the tube axis of the cathode ray tube.

In the cathode ray tube constructed as described above, as shown in FIG. 5, a deflection yoke 7 for deflecting the electron beam is attached at a position between the cone portion 1b and the neck portion 1a. And this deflection yoke 7 is comprised by the member of the horizontal deflection coil 7a, the vertical deflection coil 7b, and the deflection yoke main body part 7c, as shown in FIG.

Next, the operation will be described. When the electron beam is emitted from the electron gun 3 encapsulated in the neck portion 1a, the emitted electron beam is small in the horizontal and vertical directions by the horizontal deflection coil 7a and the vertical deflection coil 7b of the deflection yoke 7. Quantitative deflection is performed to scan the fluorescent film image formed on the inner surface of the panel 2 to illuminate the desired image. The vibration width of deflection at this time is inversely proportional to the square root of the voltage applied to the positive electrode button 1d.

The conventional cathode ray tube is constructed as described above, and when the deflection yoke deflects the electron beam, no action is taken to shield the alternating electric field that occurs radially around the deflection yoke, and the alternating current field that is harmful to the human body is a cathode ray. There was a problem in that it passes through the funnel portion and the panel portion of the tube and radiates toward the front of the cathode ray tube.

In addition, the electron beam caused by the leakage magnetic field in the flyback transformer or the like reduces the influence of Quero, and, as described in Japanese Patent Laid-Open No. 61-138433, for example, the concentrated electrode system constituting the electron gun is used. Although some of the nonmagnetic conductive magnetic shields were covered in a ring shape, the publication described in this publication has no consideration for the alternating electric field, and the alternating electric field could not be subsequently reduced.

SUMMARY OF THE INVENTION An object of the present invention is to provide a cathode ray tube apparatus capable of reducing an alternating electric field generated in a deflection yoke and radiated to a front side of a cathode ray tube.

The cathode ray tube device according to the present invention provides an AC electric field reducing means for reducing an AC electric field of a deflection yoke radiated to the front face of the face panel by passing through the funnel in a predetermined convoluted region from the cone portion into which the deflection yoke of the funnel portion is fitted.

In addition, a transparent conductive film grounded on the outer surface of the face panel is provided to form an electric field shield surface on the panel surface.

In addition, the grounded conductive film of the AC field reducing means is placed on the outer surface of the cone portion that extends from the cone portion to the region where the cone diameter is larger than the open hole diameter of the horizontal deflection coil constituting the deflection yoke. It is formed.

In the present invention, an AC electric field reduction means for reducing an AC electric field of a deflection yoke that passes through the funnel and radiates to the front face of the face panel is provided in a predetermined region from the cone portion into which the deflection yoke of the funnel portion is fitted. Since the same potential surface as that of OV, i.e., the electric field shielding surface, is formed on the inner surface of the open hole in, the permeation field radiated to the front face of the face panel through the funnel and face panel can be reduced.

Moreover, since the transparent conductive film was provided in the outer surface of a face panel, the electric field shield surface was formed in the panel surface, and the alternating electric field which permeate | transmits a face panel can be reduced.

The conductive film of the AC field reducing means is provided on the outer surface of the cone portion excluding the connecting portion of the neck portion and the cone portion on the outer surface of the cone portion having a diameter larger than the open hole diameter of the horizontal coil constituting the deflection yoke. In other words, the neck seal line portion having a weak strength has a function of preventing a phenomenon in which the electric field is concentrated in a place where the resistance value is locally maintained with a large electric resistance.

EXAMPLE

EMBODIMENT OF THE INVENTION Hereinafter, one Embodiment of this invention is described according to drawing. 1 is a block diagram of a cathode ray tube apparatus according to a first embodiment of the present invention, the same reference numerals as in FIGS. 4 to 6 show the same or corresponding parts, and (8) to form an electric field shield surface. In order to electrically contact the conductive film 6, the conductive film is formed by covering the neck portion 1a from the cone portion 1b with an abyss. The conductive film for electric field shield is formed so as to cover the front face of the open hole of the deflection yoke. In addition, (9) is an insulating sheet provided in order to electrically insulate the coil part of the said conductive film 8 and the deflection yoke 7. As shown in FIG. It is a funnel shape as shown in FIG. 2, and is adhere | attached on the cone part 1b and the neck 1a of a funnel. And as shown in FIG. 3, the deflection yoke 7 is affixed on the insulating sheet 9 of the glass valve 20 comprised as mentioned above.

Next, the operation will be described. In the cathode ray tube configured in this manner, the conductive film 8 becomes the same potential surface as the OV by grounding the conductive film 8, and the conductive film 6 is conductive with the conductive film 8. The surface having the electric field shielding effect is formed in the front region of the yoke 7 to reduce the alternating electric field transmitted through the funnel portion 1 in the deflection yoke 7 and radiated to the front face of the face panel. In addition, since the insulating sheet 9 is interposed between the coil portion of the deflection yoke 7 and the conductive film 8, the coil portion and the conductive film 8 of the deflection yoke 7 are electrically insulated. There is no problem such as discharge.

As described above, according to the present embodiment, the conductive film for the electric field shield electrically connected to the conductive film 6 from the neck portion 1a of the funnel portion 1 of the glass valve 20 to the cone portion 1b ( 8), the deflection yoke 7 is disposed on the conductive film 8 via the insulating sheet 9, and the conductive film 8 is grounded so that the front surface of the deflection yoke 7 has the same potential as OV. Since the surface is formed, the alternating electric field passing through the funnel of the deflection yoke 7 can be reduced by about 40% by this same potential surface.

Next, a second embodiment of the present invention will be described. 7 is a cross-sectional view of the cathode ray tube showing the second embodiment of the present invention, in which the conductive material is formed inside the funnel portion. In detail, (8a) is a conductive material embedded in the funnel portion 1 to cover the front face of the opening of the deflection yoke to form the electric field shield surface, for example, such as aluminum foil or (10). ) Is a metal conduction button provided in a place which is embedded in the outer surface of the funnel portion 1 to contact the conductive material 8a and does not contact the coil of the deflection yoke.

Next, the operation will be described. In the cathode ray tube device configured as described above, the conductive material 8a becomes the same potential surface as that of OV by grounding the conduction button 10, and the shield having the electric field shielding effect in the front region of the open hole portion of the deflection yoke 7. The surface is formed and the alternating electric field passing through the funnel portion of the deflection yoke 7 can be reduced by about 40% as compared with the prior art. Moreover, since the electrically conductive material 8a is embedded in the glass which comprises the funnel part 1 as a sandwich, since it is electrically insulated from the exterior, problems, such as a deflection yoke and discharge, do not arise. By doing this, there is no need to provide an insulator for insulating the deflection yoke 7 and the conductive material 8a separately.

Next, a third embodiment of the present invention will be described. In this embodiment, as shown in FIG. 8, a funnel-shaped insulation 11 having a conductive film on its inner surface is provided with an outer side of the funnel into which the deflection yoke is fitted. In detail using FIGS. 9-10, 11 is a funnel insulator which has the electrically-conductive substance 11a in the inner surface, and graphite is apply | coated as a conductive material. This insulator 11 is attached from the cone portion 1b of the funnel portion 1 to the neck portion 1a so as to cover the inner surface of the open hole portion of the deflection yoke 7 as shown in FIG. A deflection yoke 7 is attached thereto.

Next, the operation will be described. In the cathode ray tube device configured as described above, the doser film 11a becomes the same potential surface as that of the OV by grounding the conductive film 11a formed on the inner surface of the funnel-shaped insulator 11 to open the deflection yoke 7. A surface having an electric field sheet effect is formed in the front region of the hole so that the alternating electric field passing through the funnel of the deflection yoke 7 can be reduced by about 40%. Moreover, since it is in an electrically insulated state between the coil part of the uneven yoke 7, and the electrically conductive film 11a, the problem, such as discharge with the deflection yoke 7, does not arise. In addition, although graphite was applied to the inner surface of the funnel-shaped insulator 11 in this Example, the same effect is acquired also when depositing an electroconductive metal, for example, aluminum. By doing in this way, an alternating electric field can be reduced as a device attached behind, without giving special process to the glass valve 20 and the deflection yoke 7. As shown in FIG.

Next, a fourth embodiment of the present invention will be described. In this embodiment, a conductive film is provided on the inner circumferential surface of the deflection yoke via an insulating film. To describe in detail using FIG. 11, reference numeral 12 denotes an insulating coating formed to cover the horizontal coil 7a, and a conductive film 13 such as graphite is coated on the surface of the insulating coating 12. As shown in FIG. In addition, a conductive tape 14 is adhered to the conductive film 13 and extends outside the deflection yoke 7. In FIG. 11, a part of the horizontal coil 7a is exposed to make the structure easier to understand, but the insulating film 12 actually covers the entire surface of the horizontal coil 7a, and the conductive film 13 Is applied to the entire surface of the insulating film 12.

Next, the operation will be described. In the cathode ray tube device configured as described above, the conductive film 13 becomes the same potential surface as that of the OV by grounding the conductive film 13 with the conductive tape 14, and the electric field shield is applied to the front region of the deflection yoke 7. The surface having an effect is formed, and the alternating electric field passing through the funnel portion 1 of the deflection yoke 7 can be reduced by about 40%. In addition, since the insulating film 12 is interposed between the horizontal deflection coil 7a and the conductive film 13, both of them are electrically insulated so that there is no problem such as discharge with the deflection yoke.

Next, a fifth embodiment of the present invention will be described. In this embodiment, a funnel-shaped insulator in which a conductive film is formed of graphite or the like on the inner side surface is attached to the inner side of the open hole of the deflection yoke. Referring to FIGS. 12 and 13, the reference numeral 15 denotes a funnel-shaped insulator, which has a conductive film 16 coated with graphite or the like on the inner surface of the open hole, and the open hole of the deflection yoke 7. It is attached to the opening part of the deflection yoke 7 so that the horizontal deflection coil 7a located in the part may be covered. In addition, a conductive tape 14 is attached to the surface of the conductive film 16 and extends to the outside of the deflection yoke 7.

Next, the operation will be described. In the cathode ray tube device configured as described above, the conductive film 16 becomes the same potential surface as that of the OV by grounding the conductive film 16 with the conductive tape 14, and the electric field shield is applied to the front region of the deflection yoke 7. The surface having an effect is formed, and the alternating electric field passing through the funnel portion 1 of the deflection yoke 7 can be reduced by about 40%. Moreover, since a deflection yoke and a funnel-shaped insulator can be manufactured separately, mounting is easy. In addition, since the insulator 15 is interposed between the horizontal deflection coil 7a and the conductive film 16, both of them are electrically insulated so that there is no problem such as discharge with the deflection yoke. Next, a sixth embodiment of the present invention will be described. In this embodiment, a conductive film is formed only at a predetermined place of the cone portion 1b, avoiding a portion of the neck seal line 1e, which is a connecting line between the neck portion 1a of the funnel portion 1 and the cone portion 1b. That is, referring to Figs. 14 to 16, in detail, reference numeral 17 denotes a conductive film provided to form an electric field shield surface, and the conductive film 17 is coated with abyss, and the deflection yoke is horizontal. Surrounded by a circumference on the outer surface of the funnel having a diameter at least greater than the maximum diameter (7d) of the coil and a circumference on the outer surface of the funnel oriented at least 10 mm in the panel portion (2) in the direction of the tube axis (28) from the neck seal line (1e). It is formed in the area. In addition, the conductive film 17 is grounded to the conductive film 6 by the conductive tape 18. A funnel-shaped insulator 19 as shown in FIG. 15 is attached to the conductive film 17, and the insulator 19 completely covers the electric field shield conductive film 17. As shown in FIG. It is designed in size. As shown in FIG. 16, the deflection yoke 7 is attached so that the insulator 19 is interposed between the coil portion of the deflection yoke 7 and the conductive film 17. As shown in FIG. In addition, the largest diameter 7d of the horizontal coil of the deflection yoke 7 in FIG. 14 is the coil maximum diameter in the cross section at the time of cutting the horizontal coil 7a shown in FIG. 6 to SY plane. It represents. Therefore, if the X-Y cross section of a coil is an ellipse, it will show the long diameter of the ellipse.

In the cathode ray tube device configured as described above, the conductive film 17 is electrically connected to the conductive film 9 by the conductive tape 18 to be grounded, so that the conductive film l7 becomes the same potential surface as the OV, and thus the electric field shielding effect. The shield surface having the surface of the deflection yoke 7 can reduce the alternating electric field passing through the funnel 1 of the deflection yoke 7 by about 40%. The end of the conductive film 17, that is, the panel surface side, is at least deflected. Since it is a circumference larger than the maximum diameter 7d of the horizontal deflection coil of the yoke 7, the shield surface which fully shields the alternating electric field radiated | emitted from the front side of the deflection yoke 7 is formed. In addition, since the conductive film 17 is formed up to at least 10 mm away from the neck seal line 1e to the panel portion 2, the neck seal line 1e has a function of maintaining a high state of electrical resistance. Moreover, since the insulator 10 is interposed between the coil part of the deflection yoke 7 and the conductive film 17, there is an effect of electrically insulating between the above.

Next, a seventh embodiment of the present invention will be described. In this embodiment, in the sixth embodiment, a transparent conductive film is provided on the outer surface of the panel portion 2 so as to effectively reduce the alternating electric field passing through the panel 2 surface. Referring to Fig. 17 in detail, in the cathode ray tube constructed in the same manner as in the sixth embodiment, reference numeral 21 denotes a transparent conductive film formed on the surface of the panel portion 2, and the conductive tape 19 The conductive film 6 is grounded by the conductive film 6.

Next, the operation will be described. In the cathode ray tube device configured as described above, the transparent conductive film 21 is grounded by the conductive tape 19 of the transparent conductive film 21 on the surface of the panel 2 in addition to the operation of the sixth embodiment. It becomes a potential surface aligned with, and the surface which has an electric field shielding effect is formed in the panel surface, and the reduction effect of an alternating electric field can be heightened more, and an alternating electric field can be reduced about 70 to 80% with respect to a normal cathode ray tube.

Next, an eighth embodiment of the present invention will be described. In this embodiment, the heat-shrinkable one is used for the insulating sheet in the first embodiment. Referring to FIG. 18, reference numeral 22 denotes an insulating sheet having heat shrinkability, and after being fixed to span the cone portion 1b and the neck portion 1a of the funnel 1, for example, a dryer or the like is used. In this way, the heat treatment can be performed more reliably and more reliably in close contact with the funnel, whereby the reliability of the insulation can be improved in a timely manner.

In addition, although the case where the transparent conductive film 21 was provided in the outer surface of the funnel part 2 in the 6th Example was shown in this Example, the outside of the panel part 2 also in the 1st-5th Example. It is apparent that the same effect as in the present embodiment can be expected by forming the transparent conductive film 21 on the surface and grounding it.

As described above, according to the cathode ray tube apparatus according to the present invention, in a predetermined region extending from the cone portion into which the deflection yoke of the funnel portion is fitted, the alternating electric field of the planar yoke transmitted through the funnel portion and radiated to the face panel front surface is reduced. AC field reduction means was provided, and the electric field shielding surface equal to OV was formed on the inner circumferential surface of the opening of the deflection yoke, so that the electric field radiated to the front face panel through the funnel and face panel was reduced. This makes it possible to provide a cathode ray tube device with high safety.

In addition, since a transparent conductive film grounded on the outer surface of the face panel is provided, an electric field shield surface is formed on the surface of the panel, thereby reducing the alternating electric field passing through the face panel.

Also, since the AC field reducing means is separated from the neck line by at least a predetermined distance to the panel surface side, the thin line and the weak strength of the neck line part are kept in a state where the electric resistance is large and the resistance value is locally reduced. The effect of concentration can be prevented and the reliability of the cathode ray tube can be maintained.

Claims (17)

A neck portion encapsulating the electron gun disposed at the rear end of the cathode ray tube, a funnel body portion including a first conductive film grounded to add capacitance to a part of the outer surface, and a cone portion connecting the neck portion and the funnel body portion A funnel portion, a face panel having a fluorescent surface on an inner surface thereof, connected to a front end of the funnel body portion, a deflection yoke mounted on the neck portion from the cone portion of the funnel portion and deflecting an electron beam emitted from the electron gun; and the funnel portion AC field reducing means for transmitting and reducing the AC field radiated from the deflection yoke to the front surface of the face panel, wherein the AC field reducing means includes a second conductive film embedded in a predetermined area of the funnel and grounded. Cathode ray tube device. The third transparent conductive film of claim 1, further comprising a third transparent conductive film mounted on the outer surface of the face panel and grounded to reduce the alternating electric field transmitted through the funnel by the deflection yoke and radiated to the front surface of the face panel. Cathode ray tube device comprising. The method of claim 2, further comprising a conductive tape which directly connects the grounded first conductive film and the grounded third transparent conductive film and grounds each other, wherein the grounded first conductive film and the grounded first material Cathode ray tube device in which only one of the three transparent conductive films is directly connected to the ground. A neck portion encapsulating the electron gun disposed at the rear end of the cathode ray tube, a funnel body portion including a first conductive film grounded to add capacitance to a part of the outer surface, and a cone portion connecting the neck portion and the funnel body portion A funnel portion having a fluorescent surface on an inner surface thereof, a face panel connected to a front end of the funnel body portion, a deflection yoke mounted on the neck portion in the cone portion of the funnel portion and deflecting an electron beam emitted from the electron gun and the funnel portion; And an alternating electric field reducing means for transmitting and reducing the alternating electric field radiated from the deflection yoke to the front surface of the face panel, wherein the alternating electric field reducing means is disposed to cover a predetermined area of the funnel portion and is formed on an inner surface thereof. A cathode ray tube device comprising a conical insulator having a grounded second conductive film. The third transparent conductive film of claim 4, wherein the third transparent conductive film is cut off and grounded on an outer surface of the face panel to emboss the alternating electric field radiated to the front surface of the face panel by the deflection yoke. Cathode ray tube device comprising. 6. The method of claim 5, further comprising a conductive tape which directly connects the grounded first conductive film and the grounded third transparent conductive film and grounds each other, wherein the grounded first conductive film and the grounded first material are further included. Cathode ray tube device in which only one of the three transparent conductive films is directly connected to the ground. A neck portion encapsulating the electron gun disposed at the rear end of the cathode ray tube, a funnel body portion including a first conductive film grounded to add capacitance to a part of the outer surface, and a cone portion connecting the neck portion and the funnel body portion Funnel department. A face panel having a fluorescent surface on an inner surface thereof, connected to a front end of the funnel body portion, a deflection yoke mounted on the neck portion of the cone portion of the funnel portion and deflecting an electron beam emitted from the electron gun; An alternating electric field reducing means provided in a funnel portion of a predetermined region extending from the cone portion to the neck portion and reducing the alternating electric field transmitted through the funnel portion to the front surface of the face panel in the deflection yoke; And the means comprises an insulating layer formed on the inner surface of the opening of the deflection yoke and a second conductive film formed on the inner surface of the insulating layer and grounded. 8. A third transparent conductive film according to claim 7, further comprising a third transparent conductive film mounted on the outer surface of the face panel and grounded to reduce the alternating electric field transmitted through the funnel by the deflection yoke and radiated to the front surface of the face panel. Cathode ray tube device comprising. A neck portion encapsulating the electron gun disposed at the rear end of the cathode ray tube, a funnel body portion including a first conductive film grounded to add capacitance to a part of the outer surface, and a cone portion connecting the neck portion and the funnel body portion And a deflection yoke having a fluorescent surface on an inner surface thereof, a face panel connected to the front end of the funnel body portion, and a deflection yoke mounted on the inner portion of the funnel portion and deflecting an electron beam emitted from the electron gun, The deflection yoke has an alternating current field means for reducing an alternating electric field radiated from the deflection yoke, wherein the alternating current field means is provided on an inner surface of the insulation layer and an insulation layer formed on an inner surface of an open hole of the deflection yoke. Cathode ray tube device comprising a second conductive film formed and grounded. A neck portion encapsulating the electron gun disposed at the rear end of the cathode ray tube, a funnel body portion including a first conductive film grounded to add capacitance to a part of the outer surface, and a cone portion connecting the neck portion and the funnel body portion A funnel portion having a fluorescent surface on an inner surface thereof, a face panel connected to a front end of the funnel body portion, a deflection yoke mounted on the inner portion of the cone portion of the funnel portion and deflecting an electron beam emitted from the electron gun, and the funnel portion; An alternating current field means for reducing the alternating electric field transmitted through and radiated from the deflection yoke to the front face of the face panel, wherein the alternating current field reduction means is formed on a predetermined area of the surface of the funnel and grounded And an insulator formed on the surface of the second conductive film grounded to electrically insulate the deflection yoke from the conductive film. And the insulator has heat shrinkability and is heated in close contact with the surface of the grounded second conductive film after mounting the insulator on the surface of the grounded second conductive film. 10. The method of claim 8, further comprising a conductive tape which directly connects the grounded first conductive film and the grounded third transparent conductive film and grounds each other, wherein the grounded first conductive film and the grounded first material are further included. Cathode ray tube device in which only one of the three transparent conductive films is directly connected to the ground. A neck portion encapsulating the electron gun disposed at the rear end of the cathode ray tube, a funnel body portion including a first conductive film grounded to add capacitance to a part of the outer surface, and a cone portion connecting the neck portion and the funnel body portion A funnel portion having a fluorescent surface on an inner surface thereof, a face panel connected to a front end of the funnel body portion, a deflection yoke mounted on the neck portion in the cone portion of the funnel portion and deflecting an electron beam emitted from the electron gun; and the funnel portion An alternating current field means for reducing the alternating electric field transmitted through and radiated from the deflection yoke to the front surface of the face panel, wherein the alternating current field reducing means is formed on a predetermined area of the surface of the funnel and is grounded. An insulator formed on the surface of the second conductive film grounded to electrically insulate the deflection yoke from the film and the conductive film And wherein the grounded second conductive film comprises the cone portion over a second region in front of the connecting portion of the neck portion and the cone portion in a first region having a diameter larger than the open hole diameter of the horizontal deflection coil of the deflection yoke. Cathode ray tube device formed on the outer surface. 13. A third transparent conductive film as set forth in claim 12, further comprising a third transparent conductive film mounted on the outer surface of the face panel and grounded to reduce the alternating electric field transmitted through the funnel by the deflection yoke and radiated to the front surface of the face panel. Cathode ray tube device comprising. 15. The method of claim 13, further comprising a conductive tape which directly connects the grounded first conductive film and the grounded third transparent conductive film and grounds each other, wherein the grounded first conductive film and the grounded first conductive film are further included. Cathode ray tube device in which only one of the three transparent conductive films is directly connected to the ground. A neck portion encapsulating the electron gun disposed at the rear end of the cathode ray tube, a funnel body portion including a first conductive film grounded to add capacitance to a part of the outer surface, and a cone portion connecting the neck portion and the funnel body portion A funnel portion having a fluorescent surface on an inner surface thereof, a face panel connected to a front end of the funnel body portion, a deflection yoke mounted on the neck portion in the cone portion of the funnel portion and deflecting an electron beam emitted from the electron gun; and the funnel portion An alternating current field reducing means for transmitting to reduce an alternating electric field radiated from the deflection yoke to the front face of the face panel, the alternating current field reducing means including a conical insulator having a second conductive film grounded on an inner surface thereof, Cathode ray tube apparatus mounted on the inner surface of the opening part of the said deflection yoke. A third transparent conductive film mounted on the outer surface of the face panel and grounded to reduce the alternating electric field transmitted through the funnel by the deflection yoke and radiated to the front surface of the face panel. Cathode ray tube device comprising. 17. The cathode ray tube device of claim 16, further comprising a conductive tape which directly connects the grounded first conductive film and the grounded conductive film and grounds each other, wherein the grounded third transparent conductive film is directly connected and grounded. .