JP2836466B2 - Vacuum-tight container for display panel - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a vacuum airtight container for a display panel having an airtight container structure in which an anode substrate and a cathode substrate are sealed with frit glass.

[0002]

2. Description of the Related Art A fluorescent display panel is known as a display panel formed by sealing upper and lower substrates to form a vacuum-tight container structure. In this fluorescent display panel, two glass plates serving as upper and lower substrates are opposed to each other, and a glass square bar is arranged in a frame shape as a side plate at a peripheral edge portion in a gap portion in the opposed state, and fused by frit glass made of low melting glass. And an airtight container structure.

FIG. 6 schematically shows this structure. Reference numeral 40 denotes an anode substrate, and 41 denotes a cover glass, which are upper and lower substrates. Since the substrate thickness withstands atmospheric pressure, 1.3 to 3.5 mm is used depending on the size of the package. Particularly, in the case of a graphic type fluorescent display panel, a substrate having a thickness of about 5 mm is used because a spacer cannot be formed in a display area. A display pattern 42 is formed of a phosphor on the inner surface of the anode substrate 40. 43 is a grid electrode, and 44 is a filament. Anode substrate 4 on which grid electrode 43 and filament 44 are arranged
The gap between the cover electrode 41 and the cover glass 41 is vacuum-sealed. For this reason, the grid electrode 4 is formed on the anode substrate 40 on which the display pattern 42 is formed by patterning with a phosphor.
3. After the filaments 44 are arranged, the side plate glass 45 is arranged on the edge of the anode substrate 40 as shown in the figure, and sealed by the cover glass 41.

[0004] For this sealing, a frit glass (powdered glass) having a low melting point is interposed between the upper and lower portions of the side glass 45 and heated to about 500 ° C in this state. Then, the frit glass is melted, so that the anode substrate 40 and the cover glass 41 are fixed in a hermetically sealed container.

[0005]

By the way, FED (Field Emissi Display: Field Emissi)
For a display panel of the type known as on display), the gap between the anode and the cathode is, for example, 200 μm.
It is very narrow such as about m.

At this time, as in the case of the above-described fluorescent display panel, as shown in FIG. 7 , the upper and lower substrates 50 and 51 are sealed by fusing the frame-shaped side glass 55 with frit glass 56. Must be formed to a thickness of, for example, about 180 μm. However, this is very difficult in practice and cannot be a practical means. Further, the frit glass layer must be thinned, and when air bubbles are generated in the frit glass layer, a vacuum airtight leak is likely to occur.

As a countermeasure for this, for example, it is conceivable to arrange a side plate glass 55 on the inner peripheral side of the frit glass layer 56 as shown in FIG . However, in such a method, a portion where the side plate glass 55 is arranged cannot be used as a display area, and there is a problem that the display area is narrowed.

Further, in order to make such a vacuum vessel sufficiently resistant to atmospheric pressure, it is necessary to use considerably thick substrates 50 and 51. For example, a substrate having a thickness of about 5 mm is required. If used, there is a problem in that even a small display device becomes considerably heavier in weight than other types of display panels such as a liquid crystal display panel.

[0009]

SUMMARY OF THE INVENTION In view of the foregoing problems, the present invention makes it possible to easily manufacture a hermetic container for a display panel having a vacuum container structure by securing a high-precision gap, and to further display a display device. It is an object to prevent the area from being narrowed.

Therefore, in an airtight container for a display panel in which an anode substrate and a cathode substrate are sealed with frit glass to form an airtight container structure, the frit glass is melted at the frit glass sealing temperature in the sealed area. Alternatively, a spherical body that does not soften practically is arranged, and the spherical body is
The diameter defines the gap between the anode and cathode substrates
To do.

The glass fiber is further sealed at a required position in the gap between the anode substrate and the cathode substrate which does not hinder display within the display range.
Is approximately the same height as the diameter of the spherical body
By now, the spacer is to have been arranged.

[0012]

The spherical shape, such as of the working glass beads, for example, may easily manufactured accuracy of the order of diameter of 180 [mu] m.
Therefore, without occur narrow area of the display area by the incorporation of these spheres shaped body in the frit glass, to function as a spacer to obtain the gap of the upper and lower substrates. Furthermore, in addition to such a configuration, even when a substrate having a thickness of about 1 mm is used by disposing a spacer that serves as a support between the upper and lower substrates at a required position in the display range, it can sufficiently withstand atmospheric pressure. To form a vacuum container that can be countered .

[0013]

DESCRIPTION OF THE PREFERRED EMBODIMENTS An FED panel according to an embodiment of the present invention will be described below with reference to FIGS.

The applied electric field on the metal or semiconductor surface is 10 9
At about [V / m], electrons pass through the barrier and emit electrons in a vacuum even at room temperature due to the tunnel effect. This is called field emission, and a cathode that emits electrons based on such a principle is called a field emission cathode. In recent years, making full use of semiconductor processing technology, micron-sized field emission cathodes (hereinafter
It is possible to produce a surface emission type FEC comprising an array (referred to as FEC).

FIGS. 4A and 4B show an example of such an FEC called a Spindt type. FIG. 4A is a perspective view of an FEC produced by using a semiconductor processing technique, and FIG. 4B is a view showing a cross section of the FEC taken along a line AA shown in FIG. is there.

In these figures, a cathode electrode made of a metal such as aluminum is provided on a substrate, and a cone-shaped emitter is formed on the cathode electrode. A gate electrode is further provided on the cathode electrode via an SiO2 film so that the emitter is located in an opening formed in the gate electrode. That is, the tip of the cone-shaped emitter faces through a hole formed in the gate electrode.

The pitch between the cone-shaped emitters is 10
Tens of thousands to tens
Ten thousand FECs can be provided over one substrate. Furthermore, since the distance between the gate electrode and the tip of the cone of the emitter can be made submicron, electrons are emitted from the emitter by applying a voltage of only several tens of volts between the gate electrode and the cathode electrode. You can do it.

Since the FEC has a planar shape as shown in the figure, it can be used as a surface emission type field emission cathode. Field emission display (FED)
Can be built.

FIG. 5 is a view showing the structure of such an FED. In this FED, reference numeral 21 denotes a first substrate;
Y1 to y1 formed in stripes on the first substrate 1
yn indicates a cathode electrode as a Y electrode. Cathode terminals C1 to Cn to which drive pulses are supplied are connected to the cathode electrodes y1 to yn.

Further, x1 to xm represent gate electrodes as X electrodes, and are formed in a stripe shape on the cathode electrodes y1 to yn via an insulator so as to be orthogonal to the cathode electrodes y1 to yn. Then, the gate electrodes x1 to xm
Are gate terminals G1 to Gm to which a drive pulse is supplied.
Is connected. Thus, the cathode electrode (Y electrode) y1
To yn and gate electrodes (X electrodes) x1 to xm are arranged in a matrix.

Reference numeral 22 denotes a large number of holes formed in the gate electrodes x1 to xm, and emits electrons which are field-emitted from cone-shaped emitters (see FIG. 4) formed on the cathode electrodes y1 to yn. It is formed for. The gate electrodes x1 to xm and the cathode electrodes y1 to yn
A single FEC block is formed by a group of holes 22 formed at the intersections of the two and the corresponding emitters, that is, one FEC block serving as a matrix intersection corresponds to one pixel of the displayed image. .

Reference numeral 23 denotes a second substrate disposed to face the first substrate 21. .. Formed on the second substrate 23 are anode electrodes, which are arranged in stripes corresponding to the positions of the gate electrodes x1 to xm as shown in the figure. Further, an anode extraction electrode A is connected to each anode electrode 24. Reference numeral 25 denotes a phosphor, which is provided on the surface of the anode electrode 24 on the side facing the gate electrodes x1 to xm.
The electrons are excited by collision. Each of these parts is vacuum-sealed as a sealed container to form a display panel.

When an image is displayed by the FED, a substantially constant anode voltage is supplied to the anode electrodes 24 formed on the second substrate 23 by the anode extraction electrodes A, respectively. On the other hand, the cathode electrode (Y electrode)
As for y1 to yn, a scanning pulse is supplied to each of the cathode terminals C1 to Cn and scanning is performed, so that each striped cathode electrode is sequentially selected and driven.

At this time, a voltage corresponding to the data of the image signal is applied to the gate terminals G1 to Gm according to the scanning timing. As a result, the pixels of the phosphor 25 provided on the anode electrode 24 are scanned to scan the cathode electrodes y1 to y1.
Excited by the electrons emitted from n, the pixels are controlled to emit light in accordance with the voltages applied to the gate terminals G1 to Gm, and thus one screen of an image is displayed.

In order to construct such an FED, the present embodiment employs spacers and sealing means as shown in FIGS. FIG. 1 is a cross-sectional view of a part of the FED, and FIG. 2 schematically shows a state in which a first substrate 21 on which cathode electrodes y1 to yn and gate electrodes x1 to xm are disposed is viewed from a plane direction.

The gap between the anode and the cathode of the FED is set to, for example, 200 μm as shown in FIG. In order to easily manufacture the FED while maintaining this gap with high accuracy, in this embodiment, the first substrate 21 and the second substrate 2 are used.
When sealing the frit glass 3 as shown in FIG.
So that the incorporation of glass beads 30 of, for example, about a diameter 200μm as spheres matter one layer. The glass beads 30 have a melting point higher than that of the frit glass 31, and do not melt or soften practically at the sealing temperature of the frit glass 31.

Reference numeral 32 denotes a spacer made of glass fiber having a height of about 205 to 210 μm.
At a position corresponding to the gap between the phosphors patterned on the substrate 23, the substrate is disposed between the first and second substrates via a layer of frit glass 31.

The arrangement position of the spacer 32 is shown in plan view in FIG.
Are arranged at required intervals as shown in FIG. FIG. 2 is a view schematically showing each part ignoring the actual size and arrangement pitch, and the arrangement positions of the spacers 32 are not necessarily the same. Actually about 2mm in the plane direction
The spacers 32 are arranged at a pitch of the order.
The spacer 32 is softened at the sealing temperature of the frit glass 31.

When forming a panel, the spacers 32 are arranged at predetermined positions, and the first and second substrates 2 are formed.
A layer of frit glass 31 mixed with glass beads 30 is formed around 1, 23, and the state shown in FIG. 1 is obtained.

Then, heating is performed at about 500 ° C. in this state. Then, the frit glass 31 in the peripheral portion is melted and the substrates 21 and 23 are sealed, and as shown in FIG.
A panel will be formed. At this time, since the glass beads 30 do not melt, the gap between the substrates 21 and 23 is accurately determined by the glass beads 30. Further, in this embodiment, since it is not necessary to dispose the side plate glass, there is an advantage that the number of steps is reduced.

The layer of frit glass 31 is formed in a frame shape in the plane direction as shown in FIG. 2, and its width W is about 2.5 to 3 mm.
Airtightness is not impaired by mixing 0.

Further, spacers 32 are arranged at a predetermined pitch in a region serving as a display range. The spacers 32 are also fixed between the substrates 21 and 23 by melting the frit glass 31 during heating. However, at this time, since the spacer 32 itself is also softened, if the height of the spacer 32 is set to be larger than the diameter of the glass beads 30 by 5 to 10 μm, the spacer 32 is compressed as it is softened. Does not affect the gap accuracy set by. In addition, it is possible to uniformly support the atmospheric pressure. That is, there is no problem even if the heights of the spacers 32 slightly vary. For example, a variation of about ± 3% is acceptable.

After being sealed in this way, an exhaust process is performed to form an FED panel of a vacuum container. In a vacuum state, each spacer 32 can uniformly support the atmospheric pressure. As a result, the substrates 21 and 23 can be made as thin as about 1 mm, and the size and weight of the display panel can be reduced. Further, since the spacer 32 is disposed in the display area, it does not naturally cause a reduction in the display area.

The present invention is not limited to the above embodiment,
Various changes can be made within the scope of the invention. Also FE
The present invention is not limited to the C panel, and can be applied to various display panels having a vacuum-tight container structure in which the upper and lower substrates are sealed with frit glass.

[0035]

Display panel airtight container of the present invention as described above, according to the present invention is a ball-shaped body, such as glass beads mixed in the frit glass, by function as a spacer to obtain the gap of the upper and lower substrates There is an effect that a display panel having a small gap size can be manufactured accurately and easily. In the case of mixing the spherical shaped body,
There is an effect that the step of arranging the spacer means is not required.

Further, in addition to such a structure, since a spacer is provided as a support between the upper and lower substrates at a required position within the display range, the thickness of the substrate is reduced to about 1 mm, and a thin and lightweight vacuum vessel is provided. Furthermore, since the spacer serving as a support is made of a material that softens at the sealing temperature, even if there is some variation in the size of the spacer serving as the support, , while retaining the gap accuracy obtained by the ball-like body, and the relative distance between the cathode substrate and the anode substrate constant with respect to the atmospheric pressure, there is an advantage that it is possible to construct a display device without display unevenness.

[Brief description of the drawings]

FIG. 1 is an explanatory diagram of a sectional structure of a first embodiment of a display panel of the present invention.

FIG. 2 is an explanatory diagram of a planar structure of a first embodiment in which a part of a display of the display panel of the present invention is a cross section.

FIG. 3 is a perspective view of a first embodiment of the display panel of the present invention.

FIG. 4 is an explanatory diagram of an FEC block.

FIG. 5 is an explanatory diagram of an FED panel.

FIG. 6 It is explanatory drawing of the cross-section of a fluorescent display panel.

FIG. 7 FIG. 3 is an explanatory view of a conventional manufacturing method of an FED panel.
You.

FIG. 8 FIG. 3 is an explanatory view of a conventional manufacturing method of an FED panel.
You.

[Explanation of symbols]

 21, 23 substrate 22 hole 24 anode electrode 25 phosphor 30 glass bead 31 frit glass 32 spacer 33 glass fiber x1 to xm gate electrode y1 to yn cathode electrode C1 to Cn cathode terminal

────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Yuichi Kogure 629 Oshiba, Mobara-shi, Chiba Futaba Electronics Industry Co., Ltd. (56) References JP-A-2-148646 (JP, A) JP-A-2-106856 (JP, A) (58) Field surveyed (Int. Cl. ⁶ , DB name) H01J 29/86 H01J 31/12 H01J 31/15

Claims (2)

(57) [Claims] A spherical body that does not melt or soften at the sealing temperature of the frit glass is disposed in a sealing portion for sealing the anode substrate and the cathode substrate with the frit glass, and the diameter of the spherical body is According to the anode substrate and cathode substrate
In a vacuum airtight container for a display panel the gap is defined, a gap portion which faces the cathode substrate and the anode substrate, in a predetermined position that does not interfere with the display within the display range, moths
Since the lath fiber is softened at the sealing temperature,
A vacuum hermetic container for a display panel, wherein a spacer having a height substantially equal to the diameter of the shape is provided . 2. The vacuum-tight container for a display panel according to claim 1, wherein a field emission type electron source is formed on the cathode substrate.