JPS6348051Y2 - - Google Patents

Description

[Detailed Description of the Invention] [Technical Field] The present invention relates to a plasma discharge type display panel that can obtain good luminescence through ultraviolet excitation.

[Prior art]

FIG. 1 is a cross-sectional view of a conventional plasma discharge type display panel, in which a light-emitting layer 2 made of a fluorescent material that emits light when excited by ultraviolet light is formed on a front plate 1 made of transparent glass. Anode 3
There are multiple display holes 4 made of a thin glass plate between the
Spacers 5 are provided at equal pitches to maintain a certain distance.

The anode 3 is a linear electrode arranged in a direction perpendicular to the drawing, and has an ultraviolet extraction hole 6 overlapping the display hole 4.

7 is a back plate, on which a plurality of cathodes 8 made of linear electrodes are disposed, and the cathodes 8 intersect the anode 3 at right angles;
The front plate 1 and the back plate 7 are placed opposite each other so that a gap 10 is formed by the spacer 9, and the surroundings are sealed, and the display hole 4, the ultraviolet extraction hole 6, and the gap 10 are filled with He, Ne, Ar, Xe, etc. Inert gas or a mixture of these gases is injected. Gas pressure is omitted.
10 ^-3 to 100 Torr.

When a display signal is input, a voltage is applied between the selected anode 3 and cathode 8, causing discharge between the anode 3 and cathode 8 and generating ultraviolet rays. The ultraviolet rays pass through the ultraviolet extraction hole 6 provided in the anode 3 and the display hole 4 of the spacer 5, collide with the light emitting layer 2, and stimulate the phosphors in the light emitting layer 2 to emit light.

In this way, light is emitted by passing the ultraviolet rays generated by the discharge between the anode 3 and cathode 8 through the display hole 4 and colliding with the light emitting layer 2, so that the generated ultraviolet rays can be efficiently used. In order to make the light collide with the light emitting layer 2, it is better to reduce the distance between the light emitting layer 2 and the anode 3. However, it is difficult to make the spacer 5 made of a glass plate 100 μm or less, and it is difficult to provide the display holes 4 at a small pitch, so it is difficult to reduce the display dot density.

Further, the gap between the anode 3 and the cathode 8 is maintained by a spacer 9 made of a thin glass plate, but it is difficult to make the spacer 9 less than 100 μm, which has the disadvantage that the voltage applied between the anode 3 and the cathode 8 becomes high. It was hot.

Furthermore, if the thickness of the spacers 5 and 9 must be made uniform over the entire surface of the display panel, there will be an inconvenience that uneven brightness will occur. The drawback was that it caused unevenness.

[Purpose of invention]

The present invention solves the above-mentioned drawbacks of the conventional technology, and includes a light-emitting layer between the anode and the cathode.
It is an object of the present invention to generate ultraviolet rays on the light-emitting layer to obtain a good display without uneven brightness over the entire display surface and to obtain a color display.

[Structure of the idea]

In order to achieve the above-mentioned object, the present invention has an insulating transparent front plate and a back plate facing each other, and a predetermined space between the front plate and the back plate, from the front plate side to the back plate side. a first anode consisting of a plurality of transparent electrodes arranged in the direction; a light emitting layer made of a fluorescent material that emits light upon excitation of ultraviolet rays; a plurality of first anodes arranged so as to intersect at right angles to the first anode; It has a second anode formed by drilling an indicator hole at each intersection, and a plurality of hole-like parts formed so as to overlap with the above-mentioned indicator holes, and has communication between each hole-like part. at least a mesh-like spacer and a plurality of cathodes arranged so as to overlap with the second anode through the spacer,
In addition, an inert gas is injected into each of the hole-shaped portions, and a periphery between the front plate and the back plate is hermetically sealed.

〔Example〕

Examples will be described below with reference to the drawings.

FIG. 2 is a partially cutaway perspective view showing an embodiment of the display panel according to the present invention, in which linear transparent electrodes made of, for example, In ₂ o ₃ are mounted on a front plate 11 made of transparent glass. forming a patterned first anode 12;
A light-emitting layer 13 made of a fluorescent material that emits light when excited by ultraviolet rays is formed on the top by an electron beam evaporation method or a sputtering method to a thickness of about 0.2 to about 1 μm. The second anode 14 is patterned as intersecting linear electrodes. This second anode 1
4 has a plurality of display holes 15 equal to the size of the display dots arranged at equal pitches, for example.
Made of metal material such as Ni. Regarding patterning of the second anode 14, since the phosphor material is easily corroded by an acid etching solution, it is preferable to pattern the second anode 14 by a lift-off method. When using the etching method, approximately 500 ml of Sio ₂ , for example, is deposited on the light emitting layer 13.
It is preferable to deposit Ni after forming the film to a thickness of Å and then etching it.

Next, mesh-shaped spacers 1 are formed on the second anode 14 by screen printing using, for example, low-melting glass powder mixed with a binder or synthetic adhesive.
6 is formed so that its hole-shaped portion 17 overlaps with the display hole 15. A groove 18 is provided in the spacer 16, and adjacent mesh hole portions 17 communicate with each other. Further, the thickness of the spacer 16 is approximately 10 to approximately 100 μm.

Next, a cathode 20 made of a metal material such as Ni and patterned as a linear electrode is formed on another flexible back plate 19 such as a thin glass plate or a synthetic resin sheet. The first anode 12 is brought into close contact with the first anode 12 at right angles, and the surrounding area is sealed.
He, Ne, Ar,
An inert gas such as Xe or a mixture thereof is injected, and the gas pressure is kept at about 10 ^-3 to about 100 Torr.

The front plate 11 and the back plate 19 are fixed together with a spacer 16 made of adhesive. In order to maintain uniform spacing over the entire surface of the display panel, for example, a thin tungsten wire is inserted into the groove 18, and the front plate 11 and the back plate 19 are fixed together. When the back plate 19 is pressed and a low melting point glass powder is used for the spacer 16, for example, it may be fixed by heating, and the tungsten wire is removed after the fixation.

Furthermore, when using Sio ₂ or the like as the spacer 16 by vapor deposition or sputtering, the gas pressure is approximately 10 ^-3
Since the pressure is about 100 Torr, the flexible back plate 19 is bent inward and brought into close contact with the spacer 16, so no adhesive is needed.

Next, the display operation will be explained.

When no display signal is input, the second anode 14
A voltage is applied between the electrode and the cathode 20 for a very short time while scanning the plurality of second anodes 14 and the cathode 20 in a line to cause a weak discharge. This discharge is an auxiliary discharge to ensure that a strong discharge is obtained by applying one pulse when a display signal is input. I'll take a look and decide. The gap amount of this invention is approximately 10 to approximately
Since it is 100 μm, it only requires a few volts to several tens of volts.

This auxiliary discharge also generates weak ultraviolet rays,
Although the ultraviolet light passes through the display hole 15 and stimulates the light emitting layer 13, it does not emit visible light because the ultraviolet rays are weak. Therefore, the repetition rate of the line scan of the auxiliary discharge is increased to always excite the light-emitting layer 13 to a luminescent state that cannot be visually observed.

When the display signal is input, synchronization is established with the line scanning of the auxiliary discharge, and the second anode 1 is connected to the first anode 12.
When a voltage several volts higher than 4 is applied, at the intersection of the first anode 12 and the second anode 14,
Discharge occurs between the first anode 12 and the cathode 14, generating ultraviolet rays, which excites the light emitting layer 13 formed on the upper surface of the first anode 12 to emit light. At this time, light emission occurs because the gap between the first anode 12 and the cathode 20 increases by the amount of the light emitting layer 13, but the applied voltage increases by several volts, and strong ultraviolet rays are generated, resulting in visible light emission. The voltage applied between the first anode 12 and the cathode 20 is determined experimentally because it depends on how much the auxiliary discharge can contribute to display light emission and the amount of the gap.

In this type of display panel, uneven brightness occurs unless the gap between the first anode 12 and the cathode 20 is made uniform over the entire display surface, but according to the present invention, the mesh spacer 16 is formed by screen printing. It can be formed to have a uniform thickness over the entire display surface, and by using a flexible substrate for the back plate 19, the amount of gap between the first anode 12 and the cathode 20 can be made uniform. Furthermore, since the spacer 16 is provided with a groove 18 and the adjacent holes 17 are in communication, the gas pressure is uniform over the entire display panel, and discharge occurs under the same conditions over the entire display surface, resulting in uneven brightness. does not occur.

Next, if you want to obtain a color display, the light emitting layer 1
As shown in FIG.
D, G, J emit red light; B, E, H emit green light;
When C, F, and I are used to form a blue-emitting phosphor, color display can be achieved by combining the three colors.

[Effect of idea]

According to the embodiment described above, the second anode is provided, auxiliary discharge is always performed during non-display, and when a display signal is input, the discharge is reliably caused by applying one pulse between the first anode and the cathode. Furthermore, since the light-emitting layer is formed on the first anode, it has the advantage that the ultraviolet rays generated by the discharge efficiently excite the phosphor.

Further, since the display holes can be formed in the second anode made of a metal material by an etching method, there is an advantage that the arrangement pitch of the display holes can be made small. Furthermore, since the spacers are formed by screen printing, they are extremely thin and can have a uniform thickness over the entire display panel, so there is an advantage that a low voltage can be applied and a display without uneven brightness can be obtained.

In addition, the spacer also serves as an adhesive between the front plate and the back plate, and since the back plate is made of a flexible substrate, even if the front plate is warped, the second anode and cathode can be connected over the entire surface of the display panel. There is an advantage that an inexpensive glass plate can be used as the front plate because the gap can be made uniform. The first above
In this embodiment, the light-emitting layer 13 on the first anode 12 and the cathode 20 are opposed to each other, but since there is a risk that the light-emitting layer 13 may be damaged due to discharge, for example, Sio ₂ is placed on the light-emitting layer 13 as shown in FIG. By forming the protective layer 21 made of an insulating material such as , Si ₃ N ₄ to a thickness of 1 μm or less, the life of the display panel can be extended.

Furthermore, if insulating layers 22 and 23 made of a material with a high dielectric constant are formed on the second anode 14 and cathode 20 as shown in FIG. 5, a discharge will occur in the gas space when a voltage is applied for auxiliary discharge. As a result, charges of opposite polarity to the applied voltage accumulate on the surfaces of the insulating layers 22 and 23, resulting in a so-called wall voltage. Therefore, if the next voltage applied to the second anode 14 and cathode 20 is made to have the opposite polarity to the previous applied voltage, the voltage will be superimposed on the wall voltage. Therefore, if the polarity of the applied voltage is alternately applied, The applied voltage can be lowered by the wall voltage.

According to the present invention described above, it is a flat display panel that provides a good display without uneven brightness over the entire display surface, and can also display in color, so it can be used as a display for an office computer, etc. This will lead to a reduction in size.

[Brief explanation of the drawing]

FIG. 1 is a sectional view of a conventional display panel, FIG. 2 is a partially cutaway perspective view showing an embodiment of the present invention, FIG. 3 is an explanatory diagram showing an embodiment of a light emitting layer for color display, and FIG. 4 is a cross-sectional view showing another embodiment of the present invention, and FIG. 5 is also a cross-sectional view showing another embodiment of the present invention. 11... Front plate, 12... First anode, 13
...Light emitting layer, 14...Second anode, 15...Display hole, 16...Spacer, 17...Hole-shaped portion, 18
... Groove, 19 ... Rear plate, 20 ... Cathode, 2
1... Protective layer, 22, 23... Insulating layer.

Claims (1)

[Claims for Utility Model Registration] 1. An insulating transparent front plate 11 and a back plate 19 are placed opposite to each other, and between the front plate 11 and the back plate 19, there is provided a structure from the front plate 11 side to the back plate 19 side. A first anode 12 made of a plurality of transparent electrodes arranged in a predetermined direction, a light-emitting layer 13 made of a fluorescent material that emits light when excited by ultraviolet rays, and a first anode 12 arranged perpendicularly to the first anode 12. A plurality of second anodes 14 are arranged, and each of the second anodes 14 is provided with an indicator hole 15 at each intersection.
and a mesh-like spacer 16 having a plurality of hole-shaped portions 17 formed to overlap with the display hole 15 and providing communication between the hole-shaped portions 17.
and the second anode 14 via the spacer 16
A plurality of cathodes 20 are arranged so as to overlap with each other.
What is claimed is: 1. A display panel comprising at least the following: an inert gas is injected into each of the hole-shaped portions 17, and a periphery between the front plate 11 and the rear plate 19 is hermetically sealed. 2 Utility Model Registration Claim Paragraph 1 is characterized in that the light-emitting layer 13 is formed by alternately arranging fluorescent materials that emit red, blue, and green colors when excited by ultraviolet rays as dots that are equal to or larger than the display holes 15. display panel. 3. The display panel according to claim 1 of the utility model registration, characterized in that the light-emitting layer 13 has a protective layer 21 on its surface. 4. The display panel according to claim 1, wherein the second anode 14 and the cathode 20 have insulating layers 22 and 23 on their surfaces, respectively. 5. The display panel according to claim 1 of the utility model registration claim, characterized in that the back plate 19 is a flexible plate.