JPS6376232A - Discharge panel - Google Patents

Abstract

PURPOSE:To reduce the noise made from a discharge panel to the outside without losing the visibility of the discharge panel, by installing a transparent and low resistance conductive membrane on almost all the surface of a substrate at the outer side of an electrode device of the discharge panel, and grounding the conductive membrane. CONSTITUTION:To a substrate 11 of the first electrode device 10, a transparent conductive membrane 40 is spread and furnished. As the transparent conductive membrane 40, an indium tin oxide InSnOx, that is so-called ITO, is used. The ITO membrane 40 is grounded. Thereby, the noise to the upper side U is grounded and not released or little released to the outside Zx. On the other hand, since the ITO membrane 40 is transparent, it gives no influence to the visibility of the generation of the gas discharge. The substrate 21 side of the second electrode device 20 may also be coated with the ITO membrane. When it is coated, the noise to the down side D is grounded in the same manner and not released to the outside. However, it is generally allowable that the discharge panel can be visible only from one direction. Therefore, the second electrode device 20 side may be covered with a metallic shield plate usually.

Description

[Detailed Description of the Invention] [Summary] Radiation noise accompanying gas separation discharge generated in response to a high-frequency drive signal applied to an electrode in a discharge panel such as a plasma display (FDP) is removed from one side of the discharge panel. This discharge panel has a transparent conductive film for shielding formed on its surface to reduce external radiation of the radiation noise.

[Industrial application field]

The present invention relates to a discharge panel, and more particularly to a discharge panel that takes measures to reduce noise.

[Prior art]

In general, electronic devices tend to malfunction due to noise as the voltage used decreases and speed increases. Therefore, countermeasures against external noise are taken on the electronic device side, and measures are taken to isolate the noise source or reduce the noise emitted from the noise source.

The above two types of noise countermeasures are also required in a discharge display device using a gas discharge panel such as a plasma display (FDP). That is, since the discharge display control circuit system is electronic, it is necessary to take measures against external noise, and since the discharge panel itself becomes a noise source, it is necessary to reduce emission noise. The former is not a subject of the present invention because general noise countermeasures are applied.Therefore, the subject of the present invention is to reduce the latter noise emitted from the discharge panel.

An example of a conventional gas discharge panel is shown in FIG. 2. In the gas discharge panel, first and second electrode means 10.degree. 20 face each other at a predetermined distance d, and a discharge gas 30 is sealed within the distance. ing. The second electrode means 20 has a plurality of electrodes 22° to 22□ on the surface of the glass substrate 21. are formed in parallel and covered with an insulating film 23. The first electrode means 10 also includes:
In the cross section Z-Z', it has the same configuration as the second electrode means 20, and in the figure one of the electrodes 12. Only shown. Each electrode 1 of the first electrode means and the second electrode means
2.22 is orthogonal to each other, and the space between the intersection points defines a space (picture element) corresponding to one dot display. For example, electrode 12. and electrode 22. When a voltage sufficient for discharge is applied between the two, the dischargeable gas 30 at the intersection emits discharge light.

A voltage of about 90V is applied to the first electrode 12 and the second electrode 22 via a driver circuit (not shown). This drive voltage is applied as a pulse voltage of several tens of KHz based on the original oscillation of several + MH2 in the driver circuit. Therefore, electromagnetic noise may occur due to the application of such relatively high frequency and high voltage signals. It is known that this electromagnetic noise can be reduced by electrostatic shielding, electromagnetic shielding, etc.

(Problems to be Solved by the Invention) In addition to the electromagnetic noise mentioned above, radiation noise accompanying gas discharge is known from the discharge panel.
．． 21 and is radiated to the outside. Part of said electromagnetic noise may also be radiated through the substrate 11.21.

In order to prevent such radiated noise from being emitted to the outside, for example, it is not possible to simply confine the discharge panel in a grounded enclosure as in the past; in other words, at least one of the discharge panels must be visible. This is because they are not.

Therefore, it is desired to prevent the above noise from being emitted to the outside of the discharge panel without impairing the visibility of the discharge panel.

[Means and actions for solving the problem] A transparent, low-resistance conductive film is attached to almost the entire surface of the substrate facing the outside of the electrode means of the discharge panel.

By grounding the conductive membrane, the above noise is significantly reduced. On the other hand, the transparent film does not impair visibility.

The substrate side facing the outside of the other electrode means may be provided with the above-mentioned transparent conductive film or an ordinary metal shield member.

〔Example〕

An embodiment of the present invention will be described with reference to FIG.

The discharge panel shown in FIG. 1 is different from the discharge panel shown in FIG. 2 in that a transparent conductive film 40 is formed on the substrate 11 of the first electrode means 10.

The transparent conductive film 40 is made of indium-tin oxide 1H.
5nOxs so-called ITO (Indium4in・
Oxide) is used. The ITO film 40 is grounded. As a result, noise directed upward U in the figure is grounded and is not emitted to the outside Zx, or is only slightly emitted. On the other hand, IT
Since the O film 40 is transparent, it does not affect the visibility of gas discharge light emission.

The above-described ITO film can also be deposited on the substrate 21 side of the second electrode means 200. As a result, the noise directed downward in the figure is grounded as above and is not emitted to the outside. However,
Generally, the discharge panel only needs to be visible from one direction;
The electrode means 20 side may be surrounded by a normal metal shield plate.

From the standpoint of shielding, it is desirable that the ITO film 40 has low resistance. For this purpose, it is desirable to increase the film thickness. However, increasing the film thickness tends to increase the cost and reduce visibility, so it is desirable to set the film thickness appropriately depending on the generated noise.

In the embodiment shown in FIG. 1, a case is shown in which the ITO film 40 is applied to the substrate 11 to form an integral structure with the discharge panel, but a separately manufactured ITO film 40 may be attached to the substrate 10, or After the discharge panel is attached, it may be attached so as to cover the entire surface of the board 10. In principle, the ITO film 40 is grounded.

〔Effect of the invention〕

As described above, according to the present invention, noise emitted to the outside from the discharge panel can be reduced without impairing the visibility of the discharge panel.

[Brief explanation of the drawing]

FIG. 1 is a sectional view of a discharge panel according to an embodiment of the present invention, and FIG. 2 is a sectional view of a conventional discharge panel. (Explanation of symbols) 10... First electrode means, 11... Substrate, 12...
・First electrode, 13... Insulating protective film, 20...
Second electrode means, 21... Substrate, 22... Second electrode, 23... Insulating protective film, 30... Dischargeable gas, 40... Transparent conductive film.

Claims (1)

[Claims] 1. First and second electrode means (10, 20) arranged oppositely with a predetermined interval, each comprising a plurality of electrodes (12, 20) arranged in parallel. , 22) is the substrate (11,
21) formed on the first electrode means and disposed so that the electrodes of one electrode means intersect with the electrodes of the other electrode means;
and a discharge gas (3
0) is formed to emit discharge light at a corresponding intersection point in response to a high frequency signal applied to each electrode of the first and second electrode means, wherein at least one of the electrode means ( 10) A discharge panel characterized in that a transparent conductive film (40) for shielding noise accompanying the application of the high frequency signal is attached to the outer surface of the discharge panel.