JP2002044567A - Cathode ray tube system - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a cathode ray tube system that can effectively shield a leakage AC electric field emitted from a flyback transformer and lead wires of an anode. SOLUTION: The cathode ray tube system consisting of at least a deflection yoke having horizontal and vertical deflection coils, a cathode ray tube with the deflection yoke 6 mounted thereon, and a flyback transformer 9 that supplies a high voltage to an anode terminal 7 of the cathode ray tube via anode leads 10, is provided with a leakage AC electric field shielding means consisting of an insulator 26 and of a conductor 27 that shields a leakage AC electric field at least emitted from the flyback transformer 9.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a cathode ray tube device.

[0002]

2. Description of the Related Art In recent years, OA (Office Automation) devices such as computer devices have been remarkably developed, and have become so familiar that they are used not only in offices but also at home. With the spread of OA equipment, the importance of techniques for shielding a leaked magnetic field or a leaked electric field from electronic equipment has been increasing in terms of prevention of noise in electronic equipment and prevention of effects of electromagnetic waves on the human body.

[0003] In North Europe in particular, there are concerns about the effects of AC magnetic fields and AC electric fields on the human body, and standards (TCO) that define their permissible values are spreading throughout the world.

In the OA apparatus described above, a color cathode ray for displaying a color image on the phosphor screen by scanning the phosphor screen while deflecting the electron beam emitted from the electron gun by the magnetic field generated by the deflection yoke. A cathode ray tube device using a tube is widely used.

In general, a cathode ray tube has a vacuum envelope composed of a panel 1 and a funnel 2 having a funnel shape as shown in FIG. 4, and is provided with an electron gun 4 disposed in a neck 3 of the funnel 2. The emitted electron beam is deflected by a horizontal / vertical deflection magnetic field generated from a horizontal / vertical deflection coil of a deflection yoke 6 attached outside near a boundary between the large diameter portion 5 of the funnel 2 and the neck 3. The phosphor screen provided on the inner surface of the panel 1 is horizontally and vertically scanned to display an image.

The large diameter portion 5 of the funnel 2 is provided with an anode terminal 7 to which a high voltage is supplied, and a conductive film 8 is formed on the outer surface of the large diameter portion 5 except for the anode terminal 7. .

A flyback transformer 9 for generating a high voltage to be supplied to the cathode ray tube is provided outside the cathode ray tube.
Further, an anode lead wire 10 having one end connected to the anode terminal 7 is provided to supply a high voltage generated by the flyback transformer 9 to the cathode ray tube.

Since an AC electric field leaks from a cathode ray tube device in which such a cathode ray tube is incorporated, it is required to shield the leaked AC electric field in consideration of the influence on the human body.

According to the TCO standard, the leakage AC electric field has a band of 5 Hz to 2 kHz depending on the frequency of the electric field.
-1 and Band-2 of 2 kHz to 400 kHz. Of these leakage AC electric fields, Band-2
Is mainly generated from a horizontal deflection coil in a deflection yoke of a cathode ray tube.

[0010] As a relatively simple shielding means, a leakage AC electric field from the horizontal deflection coil can be intercepted by arranging a metal plate such as a stainless steel plate or a wire mesh above, below, left, right and behind the cathode ray tube device. Can be.

The leakage AC electric field radiated from the front surface of the cathode ray tube, that is, from the image display unit, is described in ITO (In).
Dim Tin Oxide or oxide film (SnO ₂ )
A transparent electromagnetic shielding plate is formed by applying a transparent conductive oxide film made of a material such as a vacuum deposition method or a spin coating method, or the transparent conductive oxide film is directly formed on the outer surface of the front panel of a cathode ray tube. Film of the product is formed by the same
This can be shielded by grounding.

Japanese Patent Application Laid-Open No. Hei 5-207404 discloses FIG.
As shown in FIG. 1, a reverse voltage supply unit 13 for generating a voltage 12 having a waveform opposite in polarity to the flyback pulse voltage 11 applied to the horizontal or vertical deflection coil of the deflection yoke 6;
A means for shielding a leakage AC electric field by means of a leakage AC electric field shielding means comprising a compensation electrode 14 connected to the reverse voltage supply unit 13 and disposed near the side wall of the reverse voltage supply unit 13 is shown.

On the circuit side for driving the cathode ray tube, a leakage AC electric field is generated by superimposing a ripple (AC voltage) on a high voltage supplied from the flyback transformer to the cathode ray tube.

In general, a high voltage (2
As shown in FIG. 6, the primary side winding 16 in the flyback transformer 9 is connected to a horizontal output transistor 15 for operating a deflection yoke, and a sawtooth wave flowing through a horizontal deflection coil 17 of the deflection yoke is provided, as shown in FIG. The flyback pulse voltage 11 (about 1 kV) generated during the current retrace period is boosted by the secondary winding 18 in the flyback transformer 9 and rectified.

However, when no load is applied to the high voltage generated from the secondary winding 18, the pulse waveform 19 shown in FIG.
When a load is applied, a ripple voltage like a sawtooth waveform 20 shown in FIG. 6 is superimposed, so that a leakage AC electric field is generated, and the anode lead wire 10 of the flyback transformer 9 and the flyback transformer 9 It is emitted from the main body to the outside of the cathode ray tube.

[0016]

As described above, the means for shielding the leaked AC electric field (Band-2) from the cathode ray tube device side includes (1) a metal plate or a metal plate on the upper, lower, left, right and rear sides of the cathode ray tube. (2) a transparent electromagnetic shielding plate having a transparent conductive oxide film formed on the front surface of the cathode ray tube, or a transparent conductive oxide film directly on the outer surface of the cathode ray tube panel (3) means for providing a conductive member between the cathode ray tube and the deflection yoke, and means for shielding the conductive member by grounding; (4) deflection yoke And a shielding means including a reverse voltage supply unit for generating a voltage having a waveform of a polarity opposite to the voltage applied to the horizontal or vertical deflection coil, and a compensation electrode connected to the reverse voltage supply unit.

However, since the countermeasures against the leakage electric field on the driving circuit side constituting the cathode ray tube apparatus have been insufficient, a countermeasure against the leakage AC electric field from the driving circuit side is required. .

The present invention has been made to solve the above problems, and provides a cathode ray tube device capable of effectively shielding a leakage AC electric field radiated from a flyback transformer or an anode lead wire portion. It is intended to do so.

[0019]

According to the first aspect of the present invention,
A cathode ray tube apparatus comprising: a deflection yoke having at least horizontal and vertical deflection coils; a cathode ray tube on which the deflection yoke is mounted; and a flyback transformer for supplying a high voltage to an anode portion of the cathode ray tube via an anode lead wire. At
At least a leakage AC electric field shielding means for shielding a leakage AC electric field radiated from the flyback transformer is provided.

According to a second aspect of the present invention, in the cathode ray tube device according to the first aspect, the leakage AC electric field shielding means is provided so as to cover at least a main body of the flyback transformer; And a grounded conductor arranged so as to cover the conductor.

According to the first and second aspects of the present invention, the cathode ray tube device is provided by the leakage AC electric field shielding means, that is, the leakage AC electric field shielding effect comprising the insulator and the conductor. In particular, it is possible to effectively shield a leakage AC electric field radiated from a flyback transformer to the outside, and to provide a cathode ray tube device capable of reducing the adverse effect of the leakage AC electric field on a human body.

The invention according to claim 3 is at least horizontal,
A cathode ray tube device comprising: a deflection yoke having a vertical deflection coil; a cathode ray tube on which the deflection yoke is mounted; and a flyback transformer for supplying a high voltage to an anode portion of the cathode ray tube via an anode lead wire. A leakage AC electric field shielding means for shielding a leakage AC electric field radiated from both the flyback transformer and the anode lead wire is provided.

According to a fourth aspect of the present invention, in the cathode ray tube device according to the third aspect, the leakage AC electric field shielding means includes an insulator provided so as to cover a main body of the flyback transformer and an anode lead wire portion. And a conductor that is provided so as to cover the insulator and is grounded.

According to the third and fourth aspects of the present invention, the cathode ray tube device is provided by the leakage AC electric field shielding means, that is, the leakage AC electric field shielding effect comprising the insulator and the conductor. Can effectively shield a leaked AC electric field radiated from both the flyback transformer and the anode lead wire to the outside, and can provide a cathode ray tube device that can reduce the adverse effect of the leaked AC electric field on the human body. .

According to a fifth aspect of the present invention, at least a horizontal,
A deflection yoke having a vertical deflection coil, a deflection yoke mounted on the deflection yoke, and a reverse voltage supply unit for generating a voltage having a waveform of a polarity opposite to that of the voltage applied to the horizontal and vertical deflection coils, and connected to the reverse voltage supply unit; In a cathode ray tube device comprising a cathode ray tube provided with a compensating electrode, and a flyback transformer for supplying a high voltage to the anode portion of the cathode green tube via an anode lead wire, at least radiation is emitted from the flyback transformer. A leakage AC electric field shielding means for shielding a leakage AC electric field is provided.

According to a sixth aspect of the present invention, the leakage AC electric field shielding means is provided so as to cover at least the main body of the flyback transformer, and is provided so as to cover the insulator and is grounded. And a conductor.

According to the fifth and sixth aspects of the present invention, the reverse voltage is supplied by the leakage AC electric field shielding means, that is, the leakage AC electric field shielding means made of the insulator and the conductor. Of the cathode ray tube device, particularly the cathode ray tube device having the compensating electrode and the compensating electrode, which can effectively shield the leaked AC electric field radiated from the flyback transformer to the outside, and reduce the adverse effect of the leaked AC electric field on the human body. A tube device can be provided.

[0028] The invention according to claim 7 is at least horizontal,
A deflection yoke having a vertical deflection coil, a deflection yoke mounted on the deflection yoke, and a reverse voltage supply unit for generating a voltage having a waveform of a polarity opposite to that of the voltage applied to the horizontal and vertical deflection coils, and connected to the reverse voltage supply unit; Wherein the flyback transformer and the anode lead wire comprise a cathode ray tube provided with a compensating electrode, and a flyback transformer for supplying a high voltage to the anode portion of the cathode green tube via an anode lead wire. And a leakage AC electric field shielding means for shielding a leakage AC electric field radiated from both of them.

According to an eighth aspect of the present invention, in the cathode ray tube device of the seventh aspect, the leakage AC electric field shielding means is provided so as to cover a main body of the flyback transformer and an anode lead wire portion. And a conductor provided to cover the insulator and grounded.

According to the seventh and eighth aspects of the present invention, the reverse voltage is supplied by the leakage AC electric field shielding means, that is, the leakage AC electric field shielding effect comprising the insulator and the conductor. To effectively shield the leaked AC electric field radiated from the flyback transformer and the anode lead wire of the cathode ray tube device provided with the section and the compensation electrode, and to reduce the adverse effect of the leaked AC electric field on the human body. Can be provided.

According to the ninth aspect of the present invention, there are provided the first and third aspects.
8. The cathode ray tube device according to any one of claims 5 and 7, wherein the cathode ray tube is selected from a color cathode ray tube and a black and white color cathode ray tube.

According to the ninth aspect of the present invention, in a cathode ray tube device including a color cathode ray tube or a black and white color cathode ray tube, it is possible to effectively shield a leaked AC electric field radiated to the outside, respectively. The adverse effect of the electric field on the human body can be reduced.

[0033]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A cathode ray tube device according to an embodiment of the present invention will be described below with reference to FIGS.
In the cathode ray tube device of the present embodiment, components having the same functions as those of the conventional example shown in FIGS. 4 to 6 are denoted by the same reference numerals.

FIG. 1 shows a cathode ray tube device according to the present embodiment. This cathode ray tube device has a vacuum envelope composed of a panel 1 provided with side walls on the periphery and a funnel 2 in a funnel shape. A phosphor screen composed of a three-color phosphor layer that emits red, blue, and green light is provided on the inner surface of the panel 1, and a shadow mask is arranged inside the panel so as to face the phosphor screen. .

On the other hand, an electron gun 4 for emitting three electron beams is arranged in the neck 3 of the funnel 2.

A deflection yoke 6 is mounted outside the vicinity of the boundary between the large diameter portion 5 of the funnel 2 and the neck 3. The large diameter portion 5 of the funnel 2 is provided with an anode terminal 7 to which a high voltage is supplied.
The conductive film 8 is provided except for the portion of the anode terminal 7.

Further, an anode lead wire 10 for supplying a high voltage generated by the flyback transformer 9 to the cathode ray tube is connected to the anode terminal 7.

The above configuration is the same as that of the conventional cathode ray tube device shown in FIG.

As shown in FIGS. 1 to 3, a cathode ray tube device according to the present embodiment has a shielding AC electric field shielding means for shielding a leaked AC electric field in addition to the configuration of a conventional cathode ray tube device. Equipment.

As shown in FIG. 1, the shielding device includes a main body shielding device 24 for shielding an AC electric field generated from the main body of the flyback transformer 9 and a main body shielding device 24 for shielding an AC electric field generated from the anode lead wire 10. Lead wire shielding device 25
It is composed of

As shown in FIG. 2, the main body shielding device 24 and the lead wire shielding device 25 each have a double structure including an insulator 26 on the inside and a conductor 27 grounded on the outside. And the outer circumference of the anode lead wire 10. The insulator 26 sufficiently insulates the high voltage generated from the flyback transformer 9 and the anode lead wire 10, and further connects the conductor 27 to a ground wire. By forming an electric field shield surface on the outer periphery of the insulator 26 by grounding through the insulator 28, the leakage AC electric field radiated from the main body of the flyback transformer 9 and the anode lead wire 10 can be reliably shielded. I have.

As shown in FIG. 2, the flyback transformer 9 includes a booster section 21 for generating a high voltage, an anode lead wire 10 for supplying the generated high voltage to the cathode ray tube, and a cathode wire It comprises an anode cap 22 for connecting to the cathode terminal 7 of the tube, and variable resistors 23 for adjusting the focus voltage and the screen voltage generated from the flyback transformer 9.

The flyback transformer 9 radiates an AC electric field due to the superposition of the ripple voltage as described above, and the leakage AC electric field radiated from the anode lead wire 10 is particularly remarkable.

In this embodiment, the high voltage generated from the anode lead wire 10 is sufficiently insulated by the insulator 26 of the lead wire shielding device 25 and the conductor 27
Is grounded via a ground wire 28 and an electric field shield surface is formed on the outer periphery of the insulator 26 so that the anode lead wire 10
This shields the leaked AC electric field radiated from the.

FIG. 3 is a partially cutaway perspective view showing a state in which the flyback transformer 9 and the anode lead wire 10 are covered with the main body shielding device 24 and the lead wire shielding device 25, respectively.

In the above-described embodiment, the structure in which the leakage electric field shielding device for shielding the main body of the flyback transformer 9 and the anode lead wire portion is attached to both of them has been described. Even if either one of the lead wire shielding devices 25 is provided independently, the leakage AC electric field radiated from the flyback transformer 9 or the anode lead wire 10 can be reliably shielded. In this case, it is necessary to individually ground each conductor 27 of the main body shielding device 24 or the lead wire shielding device 25.

In the above-described embodiment, the structure of each shielding device is the insulator 26 on the inner side and the conductor 27 on the outer side. However, in order to insulate from the components of the driving circuit in the cathode ray tube device, the shielding device is shielded. A structure may be employed in which the outside of the conductor 27 outside the device is further covered with an insulator (not shown).

Further, in the above-described embodiment, the case where the leakage AC electric field shielding means is added to the conventional cathode ray tube device having the configuration shown in FIG. 4 has been described. However, the reverse voltage supply unit 13 and the compensation electrode shown in FIG. Even if the leakage AC electric field shielding means is added to the conventional cathode ray tube device with 14, the leakage AC electric field radiated to the outside can be effectively shielded.

Further, in the above-described embodiment, a cathode ray tube device including a color cathode ray tube has been described. However, the present invention is also applied to a cathode ray tube device including a cathode ray tube for displaying a black and white image. Of course, it is also possible to shield the leakage electric field radiated from.

[0050]

According to the present invention, it is possible to effectively shield the leakage AC electric field radiated from the flyback transformer and the anode lead wire portion, and to reduce the adverse effect on the human body. A tube device can be provided.

Further, according to the present invention, even in the case of the configuration having the reverse voltage supply section and the compensation electrode, the flyback transformer,
Further, it is possible to provide a cathode ray tube device capable of effectively shielding a leaked AC electric field radiated from an anode lead wire portion and reducing an adverse effect on a human body.

According to the present invention, a color cathode ray tube,
Regardless of the configuration of the cathode ray tube, regardless of whether it is a black and white cathode ray tube, it is possible to effectively shield the leaked AC electric field radiated from the flyback transformer and even the anode lead wire portion, A cathode ray tube device capable of reducing adverse effects can be provided.

[Brief description of the drawings]

FIG. 1 is a schematic configuration diagram showing a cathode ray tube device according to an embodiment of the present invention.

FIG. 2 is a schematic configuration diagram illustrating a structure of a shielding device according to the present embodiment.

FIG. 3 is a partially cutaway perspective view showing the structure of the shielding device of the present embodiment.

FIG. 4 is a schematic configuration diagram showing a conventional cathode ray tube device.

FIG. 5 is a schematic configuration diagram showing a conventional cathode ray tube device with a compensation electrode.

FIG. 6 is a circuit diagram showing a horizontal output circuit for driving a conventional cathode ray tube device and a simplified circuit of a flyback transformer.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Panel 2 Funnel 3 Neck 4 Electron gun 5 Large diameter part 6 Deflection yoke 7 Anode terminal 9 Flyback transformer 10 Anode lead wire 24 Main body shielding device 25 Lead wire shielding device 26 Insulator 27 Conductor 28 Ground wire

Continuation of the front page (72) Inventor Toshihiro Okazaki 7-1, Nisshincho, Kawasaki-ku, Kawasaki-shi, Kanagawa Prefecture F-term in Toshiba Electronic Engineering Corporation (reference) 5C068 AA11 BA02 BA11 CB01 KA01 KA02

Claims (9)

[Claims] 1. A deflection yoke having at least horizontal and vertical deflection coils, a cathode ray tube on which the deflection yoke is mounted, and a flyback transformer for supplying a high voltage to an anode portion of the cathode ray tube via an anode lead wire. A cathode ray tube device comprising: a leakage AC electric field shielding means for shielding at least a leakage AC electric field radiated from the flyback transformer. 2. The leakage AC electric field shielding means comprises an insulator provided so as to cover at least a main body of the flyback transformer, and a conductor provided so as to cover the insulator and grounded. The cathode ray tube device according to claim 1, wherein: 3. A deflection yoke having at least horizontal and vertical deflection coils, a cathode ray tube on which the deflection yoke is mounted, and a flyback transformer for supplying a high voltage to an anode part of the cathode ray tube via an anode lead wire. A cathode ray tube device comprising: a leakage AC electric field shielding unit that shields a leakage AC electric field emitted from both the flyback transformer and the anode lead wire. 4. The leakage AC electric field shielding means includes: an insulator disposed to cover a body of the flyback transformer and an anode lead; and a conductor grounded to cover the insulator. 4. The cathode ray tube device according to claim 3, comprising: 5. A deflection yoke having at least horizontal and vertical deflection coils, and said deflection yoke is mounted on said deflection yoke.
A cathode voltage tube provided with a reverse voltage supply unit for generating a voltage having a waveform of a polarity opposite to the voltage applied to the vertical deflection coil and a compensation electrode connected to the reverse voltage supply unit; and an anode unit of the cathode green tube. A cathode ray tube device comprising a flyback transformer for supplying a high voltage via an anode lead wire, wherein the cathode ray tube device comprises a leakage AC electric field shielding means for shielding at least a leakage AC electric field radiated from the flyback transformer. Cathode ray tube device. 6. The leakage AC electric field shielding means includes an insulator disposed so as to cover at least the main body of the flyback transformer, and a conductor disposed so as to cover the insulator and grounded. The cathode ray tube device according to claim 5, wherein: 7. A deflection yoke having at least horizontal and vertical deflection coils, and said deflection yoke is mounted on said deflection yoke.
A cathode voltage tube provided with a reverse voltage supply unit for generating a voltage having a waveform of a polarity opposite to the voltage applied to the vertical deflection coil and a compensation electrode connected to the reverse voltage supply unit; and an anode unit of the cathode green tube. A cathode ray tube device comprising a flyback transformer for supplying a high voltage via an anode lead wire, comprising a leakage AC electric field shielding means for shielding a leakage AC electric field radiated from both the flyback transformer and the anode lead wire. A cathode ray tube device. 8. The leakage AC electric field shielding means includes: an insulator disposed to cover a body of the flyback transformer and an anode lead; and a conductor grounded to cover the insulator. The cathode ray tube device according to claim 7, comprising: 9. The cathode ray tube device according to claim 1, wherein the cathode ray tube is selected from a color cathode ray tube and a black and white color cathode ray tube.