JPS5816290B2 - Heimenhouden Hiyoujisouchi - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a flat discharge display device with high luminance.

This flat discharge display device was previously proposed by the present applicant, and for example, a flat bulb is formed by two insulating panels made of transparent glass substrates, and it extends in one direction on the inner surface of the front panel. A plurality of striped anodes are deposited on the inner surface of the back panel, and a plurality of striped cathodes are deposited on the inner surface of the back panel, facing the anodes and extending perpendicularly thereto. A DC discharge type XY that is coated with a phosphor that emits a desired color of light between the anodes.
M) There is an IJ flux discharge display device.

In this operation, a predetermined DC voltage is selectively applied to each anode and cathode, and the ultraviolet light generated by the discharge at the intersection between the selected anode and cathode excites and colors the phosphor near the intersection. Each desired color display is viewed from the outside of the front panel as one display segment.

For example, when displaying a television image, cathodes are arranged along the horizontal direction, and a constant voltage is sequentially applied to the cathodes every horizontal scanning period, and each anode extending vertically is applied one horizontal scanning line. The desired television image is displayed by simultaneously applying a required voltage corresponding to the luminance of each sampled point of the video signal.

However, in such a flat discharge display device capable of color display, the brightness tends to saturate to a constant value when the current value exceeds the current value as seen from the current-brightness characteristic curve a in FIG. Further improvement in brightness cannot be expected.

Judging from the amount of ultraviolet light generated, saturation of the phosphor itself cannot be considered as the cause of this, and therefore it is thought to be caused by the gas discharge system.

The present invention incorporates an AC discharge electrode with a DC discharge display electrode through an insulating layer between the display electrodes, thereby substantially increasing the amount of ultraviolet light emission and the discharge time, thereby improving the luminance as a whole. In addition, the present invention provides a flat discharge display device that is capable of independently displaying two systems of signals.

Hereinafter, the flat discharge display device according to the present invention will be explained in detail with reference to FIG. 2 and subsequent figures.

FIGS. 2 and 3 show an embodiment of the present invention, which is applied to an XY matrix type flat discharge display device coated with a phosphor to enable color display.

In the figure, 1 and 2 are insulating panels made of, for example, transparent glass substrates, which maintain a required space from each other and seal the periphery with glass frit to form a planar bulb 3. do.

Inside this bulb 3, there are a pair of XY discharge electrodes 4 facing each other for DC discharge, and a pair of XY discharge electrodes 6 for AC discharge located between these electrodes 4 and facing each other with insulating layers 5, 5' interposed therebetween. Arrange.

That is, a plurality of striped anodes 7 extending in one direction (for example, the Y direction) are formed on the inner surface of the front panel 1, and anodes 7 are formed on the inner surface of the back panel 2 in a direction perpendicular to the anodes 7, facing the anodes 7. For example, a plurality of striped cathodes 8 extending in the X direction are deposited, and the anode 7 and cathode 8 form an XY discharge electrode 4 for DC discharge.

Further, on the front panel 1, a plurality of striped stripes extending in the same direction as the anodes 7 are buried inwardly from the inner surface of the panel through an insulating layer 5 of a predetermined thickness at positions corresponding to between the anodes 7. Similarly, on the back panel 2, the cathodes 8 are buried inwardly from the inner surface of the panel at positions corresponding to the spaces between the cathodes 8, with an insulating layer 5' having a predetermined thickness interposed therebetween. A plurality of striped electrodes 10 extending in the same direction are formed, and these electrodes 9 and 10 form an XY discharge electrode 6 for AC discharge.

Note that the specific method for forming the electrodes 4 and 6 is as follows:
For example, on the inner surface of each of the front panel 1 and the back panel 2, a striped electrode 9 for AC discharge is placed in a portion corresponding to the space where the anode 7 and cathode 8 for DC discharge are to be formed.
and 10 are deposited and formed.

Next, an insulating layer 55' made of glass is placed on the entire inner surface of each panel, including the electrodes 9 and 10, with a thickness of, for example, 20 to 4
An anode 7 and a cathode 8 for direct current discharge are formed on the insulating layers 5 and 5' at portions corresponding to between the electrodes 9 and between the electrodes 10, respectively.

In this case, among the electrodes 6 for AC discharge, the electrode 9 on the front panel 1 side is made of a transparent conductive film such as an Sn02 film or an In303 film, or a conductive film with good light transmittance such as an Au film or a Pt film. It is possible to form.

On the other hand, the electrode 10 on the back panel 2 side does not need to be a transparent or light-transmitting conductive film; rather, the reflective layer is formed of a non-transparent conductive film in order to prevent light from escaping to the back panel side when emitted. It is preferable to do so.

Then, a striped phosphor 11 is formed on the insulating layer 5 on the front panel 1 side along both sides of each anode 7, that is, along one electrode 9 for AC discharge.

This phosphor 11 includes, for example, a red phosphor 11R and a green phosphor 1.
1G and blue phosphor 11B are sequentially and alternately deposited.

In this case, although the fluorescent material 11 is formed in a striped form, the fluorescent material 11 is not deposited on the portion corresponding to the intersection of the pair of electrodes 9 and 10 for AC discharge.

Incidentally, an insulating protrusion 12 made of glass, for example, is provided on the inner surface of the front panel 1 and extends in a direction perpendicular to the cathode 8 at a position corresponding to between each anode 7, and an insulating protrusion 12 made of glass, for example, is provided on the inner surface of the front panel 1 at a position corresponding to between each anode 7. A barrier electrode 13 extending parallel to the anode 7 and to which a certain required voltage is applied is applied so as to be in contact with the insulating protrusion 12 , and the barrier electrode 13 and the insulating protrusion 12
to prevent crosstalk between adjacent segments.

Next, the operation of such a configuration will be described.

Here, one independent drive circuit is provided for each of the XY electrode 4 for DC discharge and the XY electrode 6 for AC discharge.

First, a predetermined DC voltage is selectively applied to the XY electrodes for DC discharge, that is, the anode 7 and the cathode 8 through a DC drive circuit, and a discharge is caused at the intersection of the selected anode 7 and cathode 8. The ultraviolet light generated by the discharge illuminates the fluorescent material 1 near the intersection.
1 is excited and develops a color, and a desired display is performed.

At the same time, in synchronization with this DC discharge, a predetermined AC voltage is applied through the AC drive circuit to the electrodes 9 and 10 for AC discharge, which correspond closely to the selected anode 7 and cathode 8 for DC discharge, for example. The phosphor 11 in the vicinity is illuminated by ultraviolet rays based on plasma discharge at the intersection between
is excited to emit light.

In this way, the light emitted by the direct current discharge and the light emitted by the alternating current discharge are superimposed, and the overall luminance level is improved, allowing the desired color display to be viewed from the front panel 1 side.

For example, when displaying a television image, the display device is arranged so that the cathode 8 for direct current discharge runs along the horizontal direction,
A DC drive circuit is used to sequentially apply a constant voltage to each cathode 8 every horizontal scanning period, and to each anode 7 in the vertical direction, a voltage corresponding to the brightness of each sampled point of the video signal on one horizontal scanning line is applied to each cathode 8. A discharge is caused at each intersection in one horizontal line of the anode 7 and cathode 8 by applying the required voltage to each at the same time,
The fluorescent material 11 in the vicinity is excited to emit light in accordance with the brightness of the video signal.

On the other hand, the X direction (horizontal direction) adjacent to the horizontal line that discharges DC in synchronization with DC discharge through the AC drive circuit.
An alternating current voltage of a certain level is simultaneously applied between the electrode 10 and each electrode 9 in the Y direction orthogonal thereto, causing a discharge at the intersection between the electrodes 9 and 10, and exciting the phosphor 11 in the vicinity to emit light. .

Regarding the electrodes 9 in the Y direction, electrodes 9a and 9b correspond to both sides of each anode 7 partitioned by the barrier electrode 13.
may be commonly connected to each other, or may be applied with a voltage independently.

Thus, as shown in the brightness characteristics of FIG. 4, when looking at one horizontal scanning line, the brightness L2 of a constant level 15 due to AC discharge is superimposed on the brightness L1 of the video signal 14 due to DC discharge, and the overall brightness of the video signal 14 is increased. It appears that the brightness has improved.

Incidentally, although halftones cannot normally be obtained with images produced by alternating current discharge, for example, by slightly modulating alternating current discharge with a video signal as shown in the luminance characteristics of FIG.
It is also possible to improve the overall brightness by superimposing the brightness L2 of the video signal 14 on the brightness L1 of the video signal 14 generated by DC discharge.

In addition, in the upper part, the brightness due to DC discharge and AC discharge is simultaneously superimposed for one horizontal scanning line, but in addition, for example, the brightness can be changed by slightly shifting the light emission time due to DC discharge and the light emission time due to AC discharge to extend the light emission duration. Alternatively, it is also possible to perform so-called field interlacing of direct current discharge and alternating current discharge.

Furthermore, display 1 driving is not limited to line sequential driving, but point sequential driving is also possible.

Furthermore, in the above-described configuration, since the light emitting sources by direct current discharge and alternating current discharge are independent, writing operations are also possible.

For example, an image can be displayed using DC discharge, and codes, symbols, characters, etc. can be written in the image using AC discharge, and it can also be used as a two-phenomenal demonstration.

It is also possible to expand the display methods by utilizing the memory function of AC discharge.

FIG. 6 shows another embodiment of the invention.

In this method, a groove 16 of a predetermined depth is formed at each position on the front panel 1 where the fluorescent substance 11 is to be applied, one electrode 9 for AC discharge is formed in the groove 16, and an insulated electrode 9 is formed on the electrode 9. This is a case where the phosphors 11 (11R, 11G, and 11B) are formed through the glass layer 5.

The rear panel 2 side has the same configuration as in FIGS. 2 and 3.

In this configuration, as described above, it is possible to improve the brightness, display two phenomena, write other signals, etc. by using DC discharge and AC discharge, and furthermore, the coating thickness of the phosphor 11 can be adjusted by the depth of the groove 16. is controlled and a uniformly thin phosphor layer can be obtained in each part, thereby preventing a reduction in brightness due to uneven coating of the phosphor layer when light emission is observed through the phosphor layer.

Furthermore, by controlling the line width of the phosphor 11 by the width of the groove 16, a phosphor layer with a delicate pattern can be obtained.

Further, by interposing the insulating glass layer 5, the phosphor 11
The adhesion strength of the phosphor 11 can be improved by fusing it to the insulating glass layer 5.

Note that even when the insulating layer 5' at the position corresponding to the intersection of the electrodes 9 and 10 for AC discharge is selectively removed on the back panel 2 side to expose a part of the electrode 10,
Similar effects can be obtained.

FIG. 1 shows yet another embodiment of the invention.

In particular, one of the XY electrodes 6 for AC discharge, for example, the electrode 10 in the X direction, is omitted, and the cathode 8 for DC discharge is shared with the electrode 10 in the X direction for AC discharge. This is the case.

That is, the cathode 8 is set to the ground potential, a required DC voltage is applied to the anode 7 on the front panel side, and an AC voltage is applied to the electrode 9 in the Y direction for AC discharge.

In this case as well, the same effects as described above are achieved.

Further, in this case, the cathode 8 is also used as an electrode for AC discharge, but the electrode 10 for AC discharge can also be formed on the same plane as the cathode 8 by dividing the cathode 8.

As described above, according to the present invention, the light emission brightness of the display can be improved because the light emission by direct current discharge and the light emission by alternating current discharge are used together.

However, in this case, since the XY electrodes 6 for AC discharge are disposed at positions corresponding to the XY electrodes 4 for DC discharge, an AC discharge display mechanism can be configured without changing the DC discharge display mechanism in any way. Emission brightness can be improved without impairing resolution or other characteristics of the conventional XY matrix type DC discharge display mechanism.

Furthermore, the amount of direct current discharge (current) can be reduced by improving the luminance of light emission, and the life of the display device can be extended.

In addition, since the entire manufacturing process can be performed using conventional printing technology, manufacturing becomes easy.

Furthermore, by incorporating AC discharge, it is possible to write other signals, and multi-phenomenal display is also possible.

Although the above embodiment is applied to a discharge display device in which a phosphor is used to generate color, it is of course also applicable to a discharge display device in which the phosphor 11 is not coated and display is performed by discharge between the X and Y electrodes.

[Brief explanation of drawings]

Figure 1 is a current-luminance characteristic diagram used to explain the present invention;
3 and 3 are perspective views and sectional views of essential parts showing an embodiment of the present invention, FIGS. 4 and 5 are luminance characteristic diagrams for explaining the present invention, and FIGS. 6 and 7, respectively. are other embodiments of the present invention. 1 is the front panel, 2 is the back panel, 4 is the X for DC discharge
Y electrodes, 5 and 5' are insulating layers, 6 is an XY electrode for AC discharge, and 11 is a fluorescent material.

Claims (1)

[Claims] 1 Direct current discharge electrodes are arranged so as to cross each other on the inner surfaces of opposing panels, an alternating current discharge electrode is formed between each adjacent direct current discharge electrode on at least one side, and an insulating layer is formed on the alternating current discharge electrode. A flat discharge display device comprising: