JP3366026B2 - Plasma address electro-optical device - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a plasma addressed electro-optical device having a two-layer structure of an electro-optical cell such as a liquid crystal cell and a plasma cell. More specifically, it relates to a plasma cell seal structure.

[0002]

2. Description of the Related Art Conventionally, a switching element such as a thin film transistor is provided for each pixel as a means for improving the resolution and contrast of a matrix type electro-optical device using a liquid crystal cell, for example, a liquid crystal display device. A method of driving lines in a line sequential manner (so-called active matrix address method) is generally known. However, in this case, it is necessary to provide a large number of semiconductor elements such as thin film transistors on the substrate, and there is a disadvantage that the manufacturing yield is deteriorated especially when the area is increased.

Therefore, as a means for solving this disadvantage,
Buzaku et al., In Japanese Patent Laid-Open No. 1-217396, propose a method of using a plasma switch instead of a switching element composed of a thin film transistor or the like. Less than,
The configuration of a plasma addressed display device that drives a liquid crystal cell using a switch based on plasma discharge will be briefly described. As shown in FIG. 7, this device has a laminated flat panel structure including a liquid crystal cell 101, a plasma cell 102, and a partition plate 103 made of a thin glass plate interposed therebetween. The plasma cell 102 is formed using a glass substrate 104, and a plurality of grooves 105 are provided on the surface thereof. The grooves 105 extend, for example, in the row direction of the matrix. Each groove 105 is sealed by a partition plate 103 and constitutes a plasma chamber 106 which is individually separated. The plasma chamber 106 is filled with an ionizable gas. The ridges 107 that separate the adjacent grooves 105 serve as partition walls that partition the individual plasma chambers 106, and also serve as gap spacers for the plasma chambers 106. At the bottom of each groove 105, a pair of parallel plasma electrodes 108, 10 are provided.
9 is provided. The pair of electrodes function as an anode and a cathode and ionize the gas in the plasma chamber 106 to generate discharge plasma. The discharge area is a row scanning unit.

On the other hand, the liquid crystal cell 101 comprises a glass substrate 110.
It is configured using. The glass substrate 110 is arranged to face the partition plate 103 with a predetermined gap, and a liquid crystal layer 111 is filled in the gap. In addition, the signal electrode 1 made of a transparent conductive material is formed on the inner surface of the glass substrate 110.
12 are formed. The signal electrode 112 is orthogonal to the plasma chamber 106 and serves as a column drive unit. Matrix-like pixels are defined at the intersections of the column driving units and the row scanning units.

In the display device having such a structure,
Display driving is performed by line-sequentially switching and scanning the plasma chamber 106 in which plasma discharge is performed, and applying an analog drive voltage to the signal electrode 112 on the liquid crystal cell side in synchronization with this scanning. When a plasma discharge is generated in the plasma chamber 106, the inside becomes substantially uniformly at the anode potential, and pixel selection is performed for each row. That is, the plasma chamber 106 functions as a sampling switch. When a driving voltage is applied to each pixel while the plasma sampling switch is in a conducting state, sampling and holding is performed, and lighting or extinction of the pixel can be controlled. Even after the plasma sampling switch is turned off, the analog drive voltage is retained in the pixel as it is.

[0006]

By the way, in the image display device using the plasma switch as described above, it is considered that it is easier to increase the area than that using the transistor switch, but in practical use, There are various problems. For example, the groove 105 for forming the plasma chamber 106
Forming the above on the glass substrate 104 involves considerable difficulty in manufacturing. In particular, it is extremely difficult to form the grooves 105 with high density. Further, the plasma electrodes 10 are respectively provided in the grooves 105.
Although it is necessary to form 8 and 109, the etching process for this is complicated, and it is difficult to maintain the distance between the pair of electrodes with high precision.

In view of the above-mentioned problems of the prior art, the applicant has disclosed in the previously filed patent application No. 47784 of 1991 that the plasma-addressed electric power is simple to manufacture and is suitable for a large screen and high definition. An optical device is proposed. In order to clarify the object of the present invention, the device according to this prior application will be briefly described with reference to FIG. This apparatus has one glass substrate 202 having signal electrodes 201 that are substantially parallel to each other on one main surface and a plurality of plasma electrodes 203 that are substantially orthogonal to the signal electrodes and parallel to each other on one main surface. It is composed of a substrate 204. The pair of glass substrates 202 and 204 are arranged substantially parallel to each other via a partition plate made of thin glass 205. Glass substrate 2
A liquid crystal layer 206 is enclosed between 02 and the thin glass plate 205. An ionizable gas is sealed between the thin glass plate 205 and the lower glass substrate 204 to form a plasma chamber 207. A partition wall 208 is formed along each plasma electrode 203 by a printing method.
The plasma chamber 207 is divided by the partition wall 208 along the row direction and constitutes a row scanning unit. This printing method is a simple technique and is capable of forming fine patterns, and the productivity and workability are greatly improved as compared with the groove forming process in the conventional example described above. Further, since the plasma electrode 203 is formed on a flat glass substrate, the etching process is simplified and the distance between the electrodes can be controlled with high accuracy.

Next, a method of manufacturing the device shown in FIG. 8 will be briefly described with reference to FIG. First, in step S1, the electrode 203 is printed on the surface of the glass substrate 204 and baked. Next, in step S2, partition walls 208 or ribs are stacked along the electrodes 203, printed, and fired. Subsequently, in step S3, the glass substrate 204 and the thin glass plate 205 are frit-sealed to each other using low melting point glass or the like. Finally, in step S4, the upper glass substrate 2 is attached to the thin glass plate 205.
02 is adhered and a liquid crystal layer 206 is filled inside to bond the liquid crystal cell.

Returning to FIG. 8 again, the problem to be solved by the present invention will be described. As described above, when frit sealing the thin glass plate 205 to the glass substrate 204, the low melting point glass 209 is usually used. The paste-like low melting point glass 209 is quantitatively supplied along the peripheral portion of the glass substrate 204 by, for example, a dispenser. However, since the amount of paste supplied varies, it is not always possible to obtain a constant thickness. Therefore, there is a problem that unevenness is generated along the frit seal and the flatness of the thin glass plate 205 cannot be secured over the entire display surface due to the influence.

In addition, the ribs 208 are formed by thick film printing, but since they function as gap spacers, a considerable thickness is required. However, there are variations in the height of the ribs, and unevenness also occurs on the top surface of each rib. Therefore, when the rib top surfaces come into contact with the thin glass plate 205, the flatness cannot be obtained.

By the way, the processing of the plasma cell portion requires a high temperature treatment, and the processing of the liquid crystal cell can be performed at a relatively low temperature treatment. Therefore, as shown in FIG. 9, the liquid crystal cell is joined after the plasma cell is processed. At this time, there is a problem that the thickness of the liquid crystal layer 206 varies over the display surface because the thin glass plate 205 does not have flatness. If the thickness of the liquid crystal layer 206 is not uniform, operating characteristics may be adversely affected and display unevenness may occur.

[0012]

In view of the above-mentioned problems of the plasma addressed electro-optical device according to the prior application, it is a common object of the present invention to ensure the flatness of thin glass used as a partition plate. . In order to achieve such an object, in the first invention, a means for providing a flat plate spacer for defining the gap of the plasma cell between the glass substrate on the plasma cell side and the thin glass plate is provided. Low-melting-point glass was supplied along the periphery of the glass substrate along the outside of the flat plate spacer, and the thin glass plate and the glass substrate were bonded via the flat plate spacer. Then, a spacer for bonding the glass substrate of the thin glass and the liquid crystal cell side are arranged along the <br/> on the flat plate spacers.

In the second invention, a dummy electrode is formed on the glass substrate on the plasma cell side, and frit sealing is performed by using a rod-shaped low melting point glass arranged on the dummy electrode to bond the glass substrate and the thin glass plate. Measures have been taken. That
Te, a spacer for bonding the glass substrate of the thin glass and the liquid crystal cell side are arranged along the top of the rod-shaped low melting point glass.

According to the third aspect of the present invention, the dummy partition wall is formed of the same material as the partition wall on the glass substrate on the plasma cell side, and the partition wall and the dummy partition wall are provided along the peripheral portion of the glass substrate.
A continuous space was provided between them , and the space was filled with a low melting point glass to bond the plasma cell glass substrate and the thin glass plate to each other. Preferably, a spacer for bonding the thin glass and the glass substrate on the liquid crystal cell side
The Ru <br/> to distribution along the space low melting point glass is satisfied.

[0015]

In the first aspect of the invention, the flat plate spacer is arranged inside the frit seal, and the thin glass plate, the glass substrate and the flat plate spacer are integrally bonded using the low melting point glass or the solder glass paste. . At the time of thermocompression bonding, the flat glass is mainly supported by the flat plate spacer, so that the flatness can be secured. In addition, by setting the thickness of the flat plate spacer to be slightly larger than the height of the rib,
It is possible to prevent contact between the uneven rib top surface and the thin glass plate, and further improve the flatness. When the liquid crystal cell is bonded to the surface of the thin glass plate whose flatness is ensured as described above, the thickness of the liquid crystal layer is uniformly controlled over the entire display surface and the image display quality is improved.

In the second invention, the glass substrate and the thin glass plate are adhered to each other by using the rod-shaped low melting point glass. The thin glass is supported by a rod-shaped low-melting glass so as to ensure flatness. At this time, the thickness of the rod-shaped low-melting glass is set to 1.2 to 1.4 times the height of the ribs or partition walls so as to provide clearance. This method has come to be adopted by the improvement of the rib forming technique. Further, when the size is increased, it becomes easy to adjust the frit sealing time and the low melting point glass supply amount.

In the third aspect of the invention, both members are directly superposed on each other with a partition wall interposed between the glass substrate on the plasma cell side and the thin glass plate. At this time, the tops of the partition walls are flattened by polishing to make the heights uniform, and the gap between the glass substrate and the thin glass can be regulated to be constant over the entire screen, and the flatness of the thin glass can be secured. next,
The partition walls are partially removed along the periphery of the plasma cell glass substrate to provide a continuous space. In other words,
This space is surrounded by a partition wall from the inside and the outside, and a low-melting glass can be filled in this space to frit-seal the glass substrate and the thin glass plate to each other. A paste-like low-melting glass may be supplied to this space using a dispenser or the like, or a solid low-melting glass molded in a predetermined shape in advance may be arranged. In particular, by providing a notch in the partition wall located outside the space, an extra amount of low-melting glass can escape and the flatness can be further improved. Further, it becomes unnecessary to strictly control the supply amount of the low melting point glass.

[0018]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Preferred embodiments of the present invention will be described in detail below with reference to the drawings. FIG. 1 is a schematic sectional view showing an embodiment of a plasma addressed electro-optical device according to the first invention. This device has a structure in which a liquid crystal cell 1, a plasma cell 2, and a partition plate made of a thin glass plate 3 interposed therebetween are laminated. The thin glass plate 3 needs to be as thin as possible in order to drive the liquid crystal cell, and has a plate thickness of, for example, about 50 μm. The liquid crystal cell 1 has a first substrate, that is, a glass substrate 4
And a plurality of first electrodes made of a transparent conductive film, that is, signal electrodes D are formed in parallel with each other in the column direction on the inner main surface thereof. The substrate 4 is bonded to the thin glass plate 3 with a spacer 5 interposed therebetween with a predetermined gap. A liquid crystal layer 6, which is an electro-optical material layer, is filled in the gap. This gap size is usually about 5 μm and must be kept uniform over the entire display surface. For this reason, although not shown, usually, spacer particles having a predetermined particle diameter are scattered in the gap. As a result, the gap size can be controlled within an error of about ± 0.1 μm. The liquid crystal layer 6 is in contact with the signal electrode D and the thin glass plate 3. In this embodiment, liquid crystal is used as the electro-optical material, but it is not limited to this, and other fluid materials can be used. Further, although the present embodiment relates to a plasma address display device, the present invention is not limited to this, and can be widely applied to plasma address electro-optical devices such as optical modulators.

On the other hand, the plasma cell 2 is constructed by using the second substrate, that is, the lower glass substrate 7. A second electrode, that is, a plasma electrode 8 is formed on the inner main surface of the glass substrate 7. The plasma electrodes 8 alternately function as an anode A and a cathode K to generate plasma discharge. The plasma electrodes 8 are arranged along the row direction so as to intersect the signal electrodes D. A partition wall 9 or a rib is formed along the plasma electrode 8. A flat plate spacer 10 is inserted between the glass substrate 7 and the thin glass plate 3. The flat plate spacer 10 defines the gap of the plasma cell 2 and has a thickness dimension larger than the height of the partition wall 9. For example, it is set to 150 μm. In this case, a clearance of about 10 μm is left in consideration of variations in height of the partition walls 9 or rib top surfaces.
In this way, the top surface of the rib is prevented from coming into contact with the thin glass plate 3. A low melting point glass 11 is arranged outside the flat plate spacer 10 along the peripheral edge of the glass substrate 7, and adheres the thin glass plate 3 to the glass substrate 7. An airtightly sealed plasma chamber 12 is formed between the two. An ionizable gas is enclosed in the plasma chamber 12. The gas species can be selected from, for example, helium, neon, argon or a mixed gas thereof. The plasma chamber 12 is divided by the partition walls 9 or ribs, and each constitutes a row scanning unit.

When a predetermined voltage is applied between a pair of adjacent plasma electrodes 8, that is, the anode A and the cathode K, the enclosed gas is selectively ionized to form a discharge region 13 in which the ion gas is localized. . The discharge region 13 is substantially limited by the barrier ribs 9 and serves as a row scanning unit. Individual pixels are located at the intersections of the discharge regions 13 and the signal electrodes D.

As is clear from the above description, by arranging the flat plate spacer 10 between the thin glass plate 3 and the glass substrate 7, the thin glass plate 3 can be bonded flat. Therefore, when the liquid crystal cell 1 is joined, the thickness of the liquid crystal layer 6 can be uniformly controlled.

FIG. 2 shows the planar shape of the lower glass substrate 7, which is a semi-finished product at the time of frit sealing. The plasma electrode 8 and the partition wall 9 are previously formed on the surface of the glass substrate 7 in the previous step. The flat plate spacers 10 are arranged along the peripheral edge of the substrate 7. In this example, the flat plate spacer 10 is formed by processing a glass plate having a predetermined thickness into a window frame shape. The low melting point glass 11 is supplied along the outer peripheral portion of the flat plate spacer 10. In this example, paste-like low-melting glass is supplied by a dispenser.
The amount of supply is such that the height of the applied paste is the flat plate spacer 10.
Slightly over the height of.

FIG. 3 is a schematic plan view showing another structural example of the glass substrate 7. The same parts as those in FIG. 2 are designated by the same reference numerals to facilitate understanding. In this example, the flat plate spacer 10 processed into a strip shape is used. A plurality of strips are combined to surround the central portion of the substrate 7. The strip-shaped flat plate spacer 10 is easier to process than the window-frame-shaped flat plate spacer, and the yield is improved. The strip arranged so as to cross the plasma electrode 8 can be omitted. In this way, it is possible to eliminate the variation in flatness due to the film thickness of the plasma electrode 8. On the outside of the flat plate spacer 10, a low melting point glass sheet 11 which is also processed into a strip shape is arranged. This sheet is preformed and is easier to handle than paste. The thickness of the low melting point glass sheet 11 is set to be equal to or slightly larger than the thickness of the flat plate spacer 10. It should be noted that there is a slight gap between the strip-shaped sheets, but if the distance is within 0.5 mm, there is no problem because the sheet is closed by heat fusion.

Next, a method of manufacturing the plasma addressed electro-optical device shown in FIG. 1 will be described with reference to FIG. First, the electrode paste is applied to the surface of the glass substrate 7 by the screen printing method and baked to form the plasma electrode 8.

Next, a partition 9 is formed along the plasma electrode 8 by using the screen printing method. In this example, the electrodes and the partition walls are formed by so-called thick film printing. By using the printing method, it is possible to increase the size of the display device, to increase the aperture ratio, and to produce a low resistance electrode, and many other advantages.

Subsequently, the thin glass plate 3 is heat-sealed to the glass substrate 7 by frit sealing. At this time, the flat plate spacer 10 is interposed between the two. The thickness of the spacer is set so that the gap required for plasma discharge can be maintained at a level slightly exceeding the height of the partition wall 9. The thin glass 3, the glass substrate 7, and the flat plate spacer 10 are the low-melting glass 1.
Frit seal is integrally performed by 1. In this case, it is preferable that the thin glass plate, the glass substrate and the flat plate spacer all have the same coefficient of thermal expansion. If there is a significant difference in the coefficient of thermal expansion between the three, high-temperature firing is performed during frit sealing, and the expansion and contraction rate will differ, causing cracks and cracks in the thin glass sheet. In addition, the low melting point glass has the above-mentioned 3
It is preferable that the coefficient of thermal expansion is a little smaller than that of the individual glass members. If the low-melting-point glass has a large coefficient of thermal expansion, the shrinkage rate increases, and the frit seal may be cracked or the thin glass plate may be corrugated. Therefore, by reducing the coefficient of thermal expansion of the low melting point glass, it is possible to eliminate cracks and adverse effects on the thin glass sheet.

Finally, the flat glass 3 having a flatness is ensured.
The upper glass substrate 4 is adhered to the surface of the above through a sealing material such as an organic adhesive or a spacer 5. The liquid crystal layer 6 is sealed in the gap to complete the process. Spacer particles may be dispersed in order to uniformly control the thickness of the liquid crystal layer 6. The spacer 5 made of an adhesive or the like is preferably provided along the flat plate spacer 10. When a liquid crystal cell is joined, a high pressure is applied to control the gap, but the flat plate spacer 10 below the thin glass plate 3 serves as a cradle to effectively prevent damage to the thin glass plate 3.

The operation of the plasma addressed display device will be briefly described with reference to FIG. FIG. 5 shows an example of a drive circuit used in a display device. This drive circuit is composed of a signal circuit 21, a scanning circuit 22, and a control circuit 23. The signal electrodes D1 to Dm are connected to the signal circuit 21 via buffers. On the other hand, cathodes K1 to Kn are also connected to the scanning circuit 22 via buffers. The anodes A1 to An are commonly grounded. The cathode is line-sequentially scanned by the scanning circuit 22, and the signal circuit 21 supplies an analog drive voltage to each signal electrode in synchronization with this. The control circuit 23 controls synchronization between the signal circuit 21 and the scanning circuit 22. A discharge region is formed along each cathode to form a row scanning unit. On the other hand, each signal electrode serves as a column driving unit. A pixel 24 is defined between both units.

FIG. 6 is a schematic view of the two pixels 24 shown in FIG. 5 cut out. Each pixel 24 is composed of a sampling capacitor composed of a liquid crystal layer 6 sandwiched between signal electrodes (D1, D2) and a thin glass plate 3, and a plasma sampling switch S1 connected in series. The plasma sampling switch S1 is equivalent to the function of the discharge region. That is, when the discharge region is activated, the inside thereof is almost entirely connected to the anode potential. On the other hand, when the plasma discharge ends, the discharge region becomes a floating potential. The individual pixel 24 through the sampling switch S1
The so-called sampling hold is performed by writing the analog drive voltage to the sampling capacitor. The gradational lighting or extinguishing of each pixel 24 can be controlled by the level of the analog drive voltage.

FIG. 10 is a schematic sectional view showing an embodiment of the plasma address electro-optical device according to the second invention. This device has a structure in which a liquid crystal cell 1, a plasma cell 2, and a partition plate made of a thin glass plate 3 interposed therebetween are laminated. The thin glass plate 3 needs to be as thin as possible in order to drive the liquid crystal cell, and has a plate thickness of, for example, about 50 μm. The liquid crystal cell 1 has a first substrate, that is, a glass substrate 4
And a plurality of first electrodes made of a transparent conductive film, that is, signal electrodes D are formed in parallel with each other in the column direction on the inner main surface thereof. The substrate 4 is bonded to the thin glass plate 3 with a spacer 5 interposed therebetween with a predetermined gap. A liquid crystal layer 6, which is an electro-optical material layer, is filled in the gap. This gap size is usually about 5 μm and must be kept uniform over the entire display surface. For this reason, although not shown, usually, spacer particles having a predetermined particle diameter are scattered in the gap. As a result, the gap size can be controlled within an error of about ± 0.1 μm. The liquid crystal layer 6 is in contact with the signal electrode D and the thin glass plate 3. In this embodiment, liquid crystal is used as the electro-optical material, but it is not limited to this, and other fluid materials can be used. Further, although the present embodiment relates to the plasma addressed display device, the present invention is not limited to this, and can be widely applied to plasma addressed electro-optical devices such as optical modulators.

On the other hand, the plasma cell 2 is constructed by using the second substrate, that is, the lower glass substrate 7. A second electrode, that is, a plasma electrode 8 is formed on the inner main surface of the glass substrate 7. The plasma electrodes 8 alternately function as an anode A and a cathode K to generate plasma discharge. The plasma electrodes 8 are arranged along the row direction so as to intersect the signal electrodes D. Partition walls 9 or ribs are formed along the plasma electrodes 8.

Further, dummy electrodes 14 having the same shape as the plasma electrodes 8 are formed on the peripheral portions of the substrates on both sides of the plasma electrode group. The dummy electrode 14 serves as a base of the low melting point frit seal, and is arranged in order to obtain more flatness. A rod-shaped low melting point glass 11 is arranged on the dummy electrode 14, and the thin glass plate 3 and the glass substrate 7 are bonded to each other. By making the thickness of the rod-shaped low-melting glass 11 1.2 to 1.4 times the height of the rib, a clearance can be provided and a good sealing condition and flatness can be achieved. An airtightly sealed plasma chamber 12 is formed between the substrate 7 and the thin glass plate 3 which are adhered to each other. An ionizable gas is enclosed in the plasma chamber 12. The gas species can be selected from, for example, helium, neon, argon or a mixed gas thereof. The plasma chamber 12 is divided by the partition walls 9 or ribs, and each constitutes a row scanning unit.

When a predetermined voltage is applied between the pair of adjacent plasma electrodes 8, that is, the anode A and the cathode K, the enclosed gas is selectively ionized to form a discharge region 13 in which the ion gas is localized. It This discharge area 13
Is substantially limited by the partition 9 and serves as a row scanning unit. Individual pixels are located at the intersections of the discharge regions 13 and the signal electrodes D.

As is clear from the above description, the thin glass plate 3 is flatly bonded by disposing the rod-shaped or strip-shaped low-melting glass 11 between the thin glass plate 3 and the glass substrate 7 as a sealing material. You can Therefore, when the liquid crystal cell 1 is joined, the thickness of the liquid crystal layer 6 can be uniformly controlled.

FIG. 11 shows a plane shape of the lower glass substrate 7, and is a schematic plan view at the time of frit sealing.
A plasma electrode 8, a partition wall 9 and a dummy electrode 14 are previously formed on the surface of the glass substrate 7 in a previous step. At this time, the plasma electrode 8 and the dummy electrode 14 need to have the same shape and material. If the shape and material are different, the height changes and a step occurs. Flat or rod-shaped low-melting-point glass 1 formed in a strip shape having a predetermined thickness on the periphery of the substrate 7.
Place 1 The material of the rod-shaped low melting point glass 11 preferably has the same or slightly smaller thermal expansion coefficient than the substrate glass 7, and the thickness thereof is 1.2 to 1.4 times that of the partition wall 9. In this example, a rod-shaped low-melting glass 1 processed into a strip shape
1 is used. A plurality of strips are combined to surround the central portion of the substrate 7. This rod-shaped low-melting glass is easier to handle than paste and has an advantage in increasing the size. By doing so, the thin glass sheets can be bonded flat.

Next, a method of manufacturing the plasma addressed electro-optical device shown in FIG. 10 will be described with reference to FIG. First,
An electrode paste is applied to the surface of the glass substrate 7 by a screen printing method and baked to form the plasma electrode 8 and the dummy electrode 14 at the same time.

Next, a partition wall 9 is formed along the plasma electrode 8 by using the screen printing method. In this example, the electrodes and the partition walls are formed by so-called thick film printing. By using the printing method, it is possible to increase the size of the display device, to increase the aperture ratio, and to produce a low resistance electrode, and many other advantages.

Subsequently, the thin glass plate 3 is heat-sealed to the glass substrate 7 by frit sealing. At this time, the rod-shaped low melting point glass 11 is used as the frit. Rod-shaped low melting glass 1
The thickness of 1 is set to 1.2 to 1.4 times the height of the partition wall 9. It is preferable that the thin glass plate 3 and the glass substrate 7 have the same thermal expansion coefficient. If there is a significant difference in the coefficient of thermal expansion between the two, the expansion and contraction rates will differ due to high temperature firing during frit sealing, and this will cause cracks and cracks in the thin glass sheet 3. Further, the coefficient of thermal expansion of the rod-shaped low melting point glass 11 is preferably a little smaller than that of the above-mentioned two-point glass member. If the coefficient of thermal expansion of the rod-shaped low-melting glass is large, the shrinkage rate may increase, and the frit seal may be cracked or the thin glass plate may be wavy. Therefore, by reducing the coefficient of thermal expansion of the rod-shaped low-melting glass, it is possible to eliminate cracks and adverse effects on thin glass.

Finally, the thin glass plate 3 having a flatness.
The upper glass substrate 4 is adhered to the surface of the above through a sealing material such as an organic adhesive or a spacer 5. The liquid crystal layer 6 is sealed in the gap to complete the process. Spacer particles may be dispersed in order to uniformly control the thickness of the liquid crystal layer 6. The spacer 5 made of an adhesive or the like is preferably provided along the low melting point glass 11. When joining the liquid crystal cells, a high pressure is applied to control the gap, but the low melting point glass 11 under the thin glass plate 3 serves as a cradle, and the thin glass plate 3 can be effectively prevented from being damaged.

Next, an embodiment of the plasma address electro-optical device according to the third invention will be described, which is a further improvement of the plasma address electro-optical device according to the second invention. Therefore, in order to facilitate understanding of the third invention, the points to be improved of the second invention will be briefly described with reference to FIG. As shown in the figure, the thin glass plate 3 and the glass substrate 7 are bonded to each other by a rod-shaped low melting point glass 11. However, the rod-shaped low-melting glass 11 softens and deforms when heated to a high temperature.
Since the frit seal is performed by applying pressure, it is difficult to avoid deformation, and the end portion of the thin glass sheet 3 is inclined outward. Therefore, it may be difficult to secure the flatness because the thin glass sheet 3 partially projects along the inner circumference of the frit seal. Therefore, an object of the third invention is to secure evenness over the entire screen by removing even uneven portions that may be partially left.

FIG. 14 is a schematic sectional view showing an embodiment of the plasma address electro-optical device according to the third invention. This device has a structure in which a liquid crystal cell 1, a plasma cell 2, and a partition plate made of a thin glass plate 3 interposed therebetween are laminated. The thin glass plate 3 needs to be as thin as possible in order to drive the liquid crystal cell, and has a plate thickness of, for example, about 50 μm. The liquid crystal cell 1 is configured using a glass substrate 4, and a plurality of signal electrodes D made of a transparent conductive film are formed in parallel with each other in the column direction on the inner main surface thereof. The substrate 4 is bonded to the thin glass plate 3 with a spacer 5 interposed therebetween with a predetermined gap. A liquid crystal layer 6 is filled in the gap. This gap size is usually about 5 μm and must be kept uniform over the entire display screen. For this reason, although not shown, usually, spacer particles having a predetermined particle diameter are scattered in the gap. As a result, the gap size is ± 0.1μ
It can be controlled within an error of about m. The liquid crystal layer 6 is in contact with the signal electrode D and the thin glass plate 3.

On the other hand, the plasma cell 2 is constructed by using the lower glass substrate 7. A plasma electrode 8 is formed on the inner main surface of the glass substrate 7. Plasma electrode 8
Alternately function as an anode A and a cathode K to generate plasma discharge. The plasma electrodes 8 are arranged along the row direction so as to intersect the signal electrodes D. Partition walls 9 or ribs are formed along the plasma electrodes 8. Further, dummy electrodes 14 having the same shape as the plasma electrodes 8 are formed on the peripheral portions of the substrates on both sides of the plasma electrode group. Dummy partition walls 15 are formed along the dummy electrodes 14. The dummy partition wall 15 is made of the same material as the normal partition wall 9 and has the same size and shape.
However, a part of the dummy partition wall 15 is removed to provide a region where only the dummy electrode 14 is exposed. The area surrounded by the outer dummy partition wall 15 and the inner normal partition wall 9 constitutes a continuous space. This space is filled with the low-melting glass 11, and the thin glass plate 3 and the glass substrate 7 are bonded to each other. As is clear from this structure, the size of the gap between the thin glass plate 3 and the glass substrate 7 depends on the partition wall 9
Regulated by That is, in this embodiment, the top of the partition wall 9 is flattened by polishing or the like, so that the flatness of the thin glass sheet 3 can be secured. An airtightly sealed plasma chamber 12 is formed between the substrate 7 and the thin glass plate 3 which are adhered to each other by the low melting point glass 11. An ionizable gas is enclosed in the plasma chamber 12. The gas species can be selected from, for example, helium, neon, argon, xenon or a mixed gas thereof. Plasma chamber 1
Reference numeral 2 is divided by partition walls 9 or ribs, each of which constitutes a row scanning unit.

When a predetermined voltage is applied between the pair of adjacent plasma electrodes 8, that is, the anode A and the cathode K, the enclosed gas is selectively ionized to form a discharge region 13 in which the ion gas is localized. It This discharge area 13
Is substantially limited by the partition 9 and serves as a row scanning unit. Individual pixels are located at the intersections of the discharge regions 13 and the signal electrodes D.

FIG. 15 is a partial plan view showing the pattern shape of the plasma cell glass substrate 7. (A) shows an electrode pattern shape, (B) shows a partition pattern shape. First (A)
As shown in, a plurality of plasma electrodes 8 are formed in stripes in the inner screen area surrounded by the dotted line. The ends of the plasma electrode 8 are alternately extended to form a lead electrode 16 for external connection. A striped dummy electrode 14 is also formed in the peripheral region located outside the dotted line.

Next, as shown in (B), a normal partition wall 9 is formed along the plasma electrode 8. A dummy partition wall 15 is formed along the dummy electrode 14 and the extraction electrode 16. The dummy partition wall 15 is partially removed along the peripheral portion of the glass substrate 7 to form a continuous space 17. By filling the space 17 with low melting glass, the glass substrate 7 and the thin glass plate are bonded to each other. A paste-like low melting point glass can be supplied to this space 17 using a dispenser or the like. In this case, the dummy partition wall 15 functions as a bank for preventing the paste from flowing out. Further, when supplying a solid low-melting-point glass that has been formed in a strip shape in advance, the dummy partition wall 15 functions as a stopper for positioning guide.
In addition, the dummy partition wall 1 formed along the dummy electrode 14
A cutout 18 is partially provided in 5 and when a surplus portion is generated due to variations in the supply amount of the low melting point glass, the cutout 18 can be released to the outside. Therefore, the flatness can be maintained along the frit seal.

Next, a method of manufacturing the plasma addressed electro-optical device shown in FIG. 14 will be described with reference to FIG. First,
An electrode paste is applied to the surface of the glass substrate 7 by a screen printing method and baked to form the plasma electrode 8 and the dummy electrode 14 at the same time.

Next, a normal partition 9 is formed along the plasma electrode 8 and a dummy partition 15 is formed along the dummy electrode 14 by using the screen printing method. At this time, the dummy partition wall 15 is partially removed to secure the space 17 for the frit seal described above. In this example, the electrodes and the partition walls are formed by so-called thick film printing. By using the printing method, it is possible to increase the size of the display device, increase the aperture ratio, and produce an electrode with low resistance, and many other advantages are obtained. The partition walls 9 or ribs are formed by thick film printing, but since they function as gap spacers, a considerable thickness is required. However, there are variations in the height of the ribs, and unevenness also occurs on the top surface of each rib. For this reason, in this embodiment, after the thick film printing and baking, the rib top surface is flattened by performing a polishing process.

Subsequently, a sufficient amount of the low melting point glass 11 is supplied to the space 17 and the thin glass plate 3
Abut on the top surface of the flattened rib. In this state, pressurization heat treatment is applied, and a thin glass plate 3 is attached by a frit seal.
Is thermally fused to the glass substrate 7. At this time, it is preferable that the thin glass plate 3 and the glass substrate 7 have the same coefficient of thermal expansion. If there is a significant difference in the coefficient of thermal expansion between the two, the expansion and contraction rates will differ due to high temperature firing during frit sealing, and this will cause cracks and cracks in the thin glass sheet 3.

Finally, the flat glass 3 having a flatness is ensured.
The upper glass substrate 4 is adhered to the surface of the above through a sealing material such as an organic adhesive or a spacer 5. The liquid crystal layer 6 is sealed in the gap to complete the process. Spacer particles may be dispersed in order to uniformly control the thickness of the liquid crystal layer 6. The spacer 5 made of an adhesive or the like is preferably provided along the low melting point glass 11. When joining the liquid crystal cells, a high pressure is applied to control the gap, but the low melting point glass 11 under the thin glass plate 3 serves as a cradle, and the thin glass plate 3 can be effectively prevented from being damaged.

[0050]

As described above, according to the first aspect of the invention, the glass substrate is frit-sealed via the flat plate spacer to the thin glass plate for partitioning the liquid crystal cell and the plasma cell. This has the effect of ensuring flatness. Also, thin glass, flat spacers,
Since the glass substrate can be heat-fused at one time by using the low melting point glass, there is an effect that the workability is excellent. Further, when the liquid crystal cells are joined after the frit sealing is performed, the flat plate spacer can be used as a pedestal for high pressure adhesion processing, so that the plasma cell can be effectively prevented from being damaged.

As described above, according to the second invention,
For thin glass that separates liquid crystal cell and plasma cell,
The method of frit-sealing a glass substrate using a rod-shaped low-melting glass has an effect of ensuring the flatness of thin glass. In addition, it is easier to handle than conventional paste-like frit glass and is suitable for larger size.

As described above, according to the third invention,
Since the thin glass plate is supported through the flattened partition wall, there is an effect that excellent flatness can be secured. In addition, a part of the partition wall is removed along the periphery of the glass substrate to provide a continuous space, and low-melting glass is supplied to this space to perform frit sealing.
There is an effect that workability can be remarkably improved as compared with the conventional one.

[Brief description of drawings]

FIG. 1 is a schematic sectional view showing an embodiment of a plasma address electro-optical device according to the first invention.

FIG. 2 is a schematic plan view showing the configuration of a glass substrate used in the device shown in FIG.

FIG. 3 is a schematic plan view showing a modification of the same.

FIG. 4 is a process drawing showing the manufacturing method of the plasma address electro-optical device shown in FIG.

FIG. 5 is a circuit diagram for explaining the operation of the plasma address electro-optical device.

FIG. 6 is a schematic diagram in which a pixel portion of a plasma addressed electro-optical device is cut out and shown.

FIG. 7 is a perspective view showing an example of a conventional plasma address electro-optical device.

FIG. 8 is a schematic cross-sectional view showing a plasma addressed electro-optical device disclosed in the previous application.

9 is a flowchart showing a method for manufacturing the device shown in FIG.

FIG. 10 is a schematic cross-sectional view showing an embodiment of the plasma address electro-optical device according to the second invention.

11 is a schematic plan view showing a configuration of a glass substrate used in the device shown in FIG.

FIG. 12 is a process drawing showing the manufacturing method of the plasma address electro-optical device shown in FIG.

FIG. 13 is a schematic diagram for explaining points to be improved in the plasma addressed electro-optical device according to the second invention.

FIG. 14 is a schematic sectional view showing an embodiment of a plasma address electro-optical device according to the third invention.

15 is a schematic partial plan view showing the configuration of a glass substrate used in the device shown in FIG.

16 is a process diagram showing a manufacturing method of the plasma address electro-optical device shown in FIG.

[Explanation of symbols]

1 Liquid crystal cell 2 Plasma cell 3 thin glass 4 glass substrates 5 spacers 6 Liquid crystal layer 7 glass substrate 8 plasma electrodes 9 partitions 10 Flat plate spacer 11 Low melting glass 12 Plasma chamber 13 discharge area 14 Dummy electrode 15 dummy partition 17 spaces 18 notches A anode D signal electrode K cathode

   ─────────────────────────────────────────────────── ─── Continued front page       (56) References Japanese Patent Laid-Open No. 1-217396 (JP, A)                 JP-A-57-85023 (JP, A)                 JP-A-1-177018 (JP, A)                 JP 62-246226 (JP, A)                 JP-A-4-26036 (JP, A)                 JP-A-57-35831 (JP, A)                 Actual development Sho 54-93364 (JP, U)                 51-73053 (JP, U)

Claims (4)

(57) [Claims] 1. A first substrate having a plurality of first electrodes arranged parallel to each other along a principal surface, and a plurality of first substrates orthogonal to the first electrode and parallel to each other along the principal surface. A second substrate having a second electrode and a partition formed on the second electrode and arranged to face the first substrate, and a liquid crystal provided in contact with the first electrode. Layers and
Thin glass provided on the opposite side of the plurality of first electrodes so as to be in contact with the liquid crystal layer, and plasma provided for sealing an ionizable gas between the thin glass and the second substrate A plasma address electro-optical device including a chamber, wherein a flat plate spacer that defines a gap of the plasma chamber is provided between the second substrate and the thin glass plate, and the flat plate is a peripheral portion of the second substrate. A low melting point glass is arranged along the outer side of the spacer to bond the second substrate and the thin glass plate to flatten the thin glass plate, and the spacer for bonding the thin glass plate and the first substrate is formed. A plasma address electro-optical device characterized by being arranged along a flat plate spacer to make the thickness of the liquid crystal layer uniform. Wherein a first substrate having a plurality of first electrodes arranged parallel to each other along the main surface, a plurality of orthogonal to the first electrode and are arranged parallel to each other in the second electrode Toko
A second substrate having a partition wall formed on a second electrode and arranged so that the second electrode faces the first electrode; and a second substrate interposed between the first and second substrates. A liquid crystal layer, a thin glass plate provided so as to contact the liquid crystal layer on the side opposite to the first electrode, and an ionizable gas formed between the thin glass plate and the second substrate. In the plasma addressed electro-optical device including the plasma chamber, a dummy electrode having the same shape as the second electrode is formed on the second substrate, and a rod-shaped low melting point glass is disposed on the dummy electrode. The second substrate and the thin glass plate are bonded to each other with the rod-shaped low-melting glass to flatten the thin glass plate, and a spacer for bonding the thin glass plate and the first substrate is provided on the rod-shaped low-melting glass plate. Along with the thickness of the liquid crystal layer Plasma addressing electro-optical device characterized in that it Ichika. 3. A first substrate having a plurality of first electrodes arranged parallel to each other along a main surface, and a plurality of first substrates orthogonal to the first electrode and arranged parallel to each other along the main surface. A second substrate having a second electrode and a partition wall formed on the second electrode and arranged to face the first substrate, and an electrical device provided in contact with the first electrode. An optical material layer, a thin glass plate provided so as to be in contact with the electro-optical material layer on the side opposite to the plurality of first electrodes, and an ionizable gas is sealed between the thin glass plate and the second substrate. In the plasma address electro-optical device including a plasma chamber provided for the purpose, a dummy partition wall is formed of the same material as the partition wall on the second substrate, and the dummy partition wall is formed along the peripheral portion of the second substrate. There is a continuous gap between the partition and the dummy partition. The over scan provided a plasma addressing electro-optical device, characterized in that the said sheet glass and the second substrate and filling the low melting point glass in said space and bonded to each other. 4. The plasma addressed electricity according to claim 3, wherein spacers for adhering the thin glass plate and the first substrate are arranged along the space filled with the low melting point glass. Optical device.