JPS646442B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a matrix-type electro-optic display device, and more particularly to a matrix-type electro-optic display panel structure and a matrix-type electro-optic display device using the same.

Conventionally, matrix-type electro-optical display devices have a plurality of strip-shaped electrodes in the X-axis direction and strip-shaped electrodes in the Y-axis direction, which are opposed to each other in an intersecting manner. XY matrix type electro-optical display panels are well-known, in which an electro-optical material such as a field-effect liquid crystal material exhibiting a nematic phase or cholesteric phase or an electrochromic material containing viologen or pyrazoline is interposed.
Band-shaped electrodes in the X-axis direction and strip-shaped electrodes in the Y-axis direction were appropriately selected, and a plurality of selected points were combined to display desired characters, numbers, figures, and images.

In such an XY matrix type electro-optical display panel, a cross effect (also called crosstalk), in which an electro-optic phenomenon occurs even at half-selected points other than selected points, is likely to occur, and driving methods such as voltage averaging method or high-frequency bias method are usually used. has been adopted. However, when displaying television images on an XY matrix type electro-optic display panel, if you try to line-sequentially scan the XY matrix type electro-optic display panel in synchronization with the TV signal, driving methods such as voltage averaging method or high frequency bias method are required. As long as this method is adopted, the practical number of strip-shaped electrodes that can be scanned line-sequentially in synchronization with the television signal is up to several dozen, due to the cumulative response nature of the electro-optic display panel and the limit of the scanning frequency of the television signal. Even if it is possible to scan a number of images, it is impossible to scan a larger number, and the quality of the television image will inevitably be extremely poor.

From this point of view, double or quadruple matrix electro-optical display panels have been proposed in the past (Japanese Patent Publication No. 53-27150), and attempts have been made to double or quadruple the apparent number of scanning lines. However, as the structure of the electro-optic display panel becomes more complex, the specific resistance of the strip electrodes increases, making it difficult to manufacture large-sized electro-optic display panels.

On the other hand, a matrix-type electro-optic display device is well known, which is constructed by arranging a plurality of MOS switching arrays in a matrix on a silicon substrate, and providing an electro-optic display panel on the top surface in a stacked manner.
However, in such a matrix-type electro-optic display device, a driving voltage containing a DC component is applied to the electro-optic material, so the electro-optic material is easily decomposed or destroyed, and the life of the electro-optic display panel is extremely short, making it impractical for practical use. There was an unexpected defect. In the past, in order to prevent such defects, MOS transistors were formed on the substrate.
A dielectric layer is provided between the switching array and the electro-optic material layer, and electrically, a capacitor is interposed in series between the switching element and the electro-optic material to block the DC component (for example, U.S. Pat. No. 3,765,011,
3862360) or an amorphous semiconductor layer having bidirectional nonlinear switching characteristics is provided between the MOS switching array formed on the substrate and the electro-optic material layer, and only an AC voltage of a certain value or higher is selectively applied. (e.g., U.S. Pat. No. 4,028,692,
U.S. Patent No. 4,062,626), etc. were proposed. However, these matrix-type electro-optic display devices have extremely complex structures, the large-area substrates that form the switching arrays are very difficult to obtain and expensive, and it is extremely difficult to manufacture all of the large number of switching elements without defects. Overall, the manufacturing yield of display devices is low, and as a practical matter, it is almost impossible to manufacture large-area display devices. In addition, these matrix-type electro-optic display devices cannot be heat-treated at temperatures exceeding 400 to 500 degrees Celsius after forming the MOS switching array, making it impossible to hermetically seal the electro-optic display panel. Oxidation of the electro-optic material or leakage of the electro-optic material cannot be avoided, and the reliability of the display device is extremely poor.

On the other hand, in the past, a field-effect liquid crystal material was interposed between an electrode substrate and a transparent electrode plate, in which multiple electrodes made of a dark non-corrosive conductive material such as graphite or tungsten carbide and resin were embedded in an insulating substrate. Although an electro-optical display panel has been proposed (Utility Model Publication No. 10912/1983), a reaction between the liquid crystal substance and the conductive material or resin occurs during the application of electricity, promoting decomposition of the liquid crystal. Further, the liquid crystal substance permeates and leaks from the electrode portion. Since heat treatment cannot be performed at high temperatures and hermetic sealing of electro-optical display panels cannot be performed, the reliability in practical use is extremely poor.

The present invention has been developed by the inventors who have consistently promoted the development of this aspect since they first filed Utility Application No. 107628/1983.
The present invention was completed as a result of various trial production and life tests carried out over many years, and the device of the present invention is easier and cheaper to manufacture than any of the conventional devices mentioned above, and can be manufactured over a relatively large area. The present invention provides a highly reliable matrix-type electro-optic display device that can be manufactured very efficiently even in the case of a display device of 100 to 100%, and in which the electro-optic display panel itself is hermetically sealed.

Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.

FIG. 1 shows an overall embodiment of a matrix type electro-optic display device according to the present invention. As shown in the figure, the matrix type electro-optical display device of the present invention has a dot matrix type electro-optic display panel 10, has very high electrical resistance in the horizontal direction, partially low electrical resistance in the vertical direction, and has physical elasticity. The LSI circuit 30 includes a connecting body 20 and a FET switching array having an AC output terminal modulated by a time signal and arranged in a matrix.

Dot matrix type electro-optical display panel 10
The front substrate 11 and the back substrate 1 are opposed to each other.
2. One front substrate 11 is made of glass, for example, which may have low insulation but is at least transparent, and the lower surface of the front substrate 11 is made of In ₂ O _{3 or}
A transparent and highly conductive thin film electrode 13 made of SnO ₂ is deposited.

The other back substrate 12 is made of SiO as shown in the second figure.
For example, borosilicate glass produced using SiO ₂ , B ₂ O ₃ , Na ₂ O, etc. as raw materials is heated to separate the phases of the vitreous plate-like block 14 whose main components are B ₂ O 3 and Na ₂ O.
A plurality of rod-shaped blocks ₁₅ , 15, .
A plate-shaped base material in which 5, 15, . . . are interconnected and integrated through a Si-O skeleton is used. The plate-like base material is treated with a strong acid such as sulfuric acid to dissolve and precipitate the phase portion rich in B ₂ O ₃ and Na ₂ O to make the rod-shaped blocks 15, 15... porous. The rod-shaped blocks 15, 15... are impregnated with a conductive material with good permeability and high conductivity, such as silicon carbide resin, silver phenol resin, aluminum phenol resin, carbon phenol resin, graphite phenol resin, etc. Afterwards, it is washed and dried, and a plurality of electrodes penetrating the back substrate 12 are embedded in a matrix. Further, as shown in FIG. 3, the back substrate 12 is made by heating and phase-separating the above-mentioned borosilicate glass between glass rod-shaped blocks 14', 14', whose main component is SiO ₂ . Rod-shaped blocks 15, 15... are arranged in a two-dimensional matrix shape in the horizontal direction, and then tightened from the periphery and heated and fired while applying an external force to form the rod-shaped blocks 1.
4', 14'... and rod-like blocks 15, 15... may be connected to each other by the Si--O skeleton and integrated, and then a plate-shaped base material sliced in the transverse direction may be used as appropriate. Note that the shape of the electrodes, the surface area of the electrodes, and the mutual spacing between the electrodes are determined by the rod-shaped blocks 14',
14'...or rod-shaped blocks 15, 15...
can be freely selected by appropriately selecting the shape and surface area of the surface. Further, in any of the above-described embodiments, there is no risk that the conductive material will penetrate into any area other than the porous portion, and there is no necessity for the electrodes embedded in a matrix to short-circuit with each other. Next, back base material 1
As shown in FIG. 4, the inward facing surface of 2 is made of an amorphous material that bleeds easily into the back substrate 12, has excellent airtightness, exhibits bidirectional nonlinear characteristics, and has a large dielectric constant. The film 16 is uniformly applied over the entire surface. The amorphous thick film 16 is made of, for example, SiO ₂ and Ga, Ba, Te,
A mixed material containing at least three types of components such as As, Ti, Li, etc. in a predetermined ratio is suitable, and after heating the back substrate 12 appropriately in a vacuum, the mixed material is sputtered or vapor-deposited. Then, an amorphous thick film 16 having a thickness of about 1000 to 10000 Å is deposited (see FIG. 4a). This amorphous thick film 16
and the back substrate 12 are Si-
The O skeletons become more closely bonded to each other, forming an amorphous thick film 16.
penetrates the back base material 12 and protects the plurality of electrodes buried therein. In addition, the amorphous thick film 16 electrically exhibits bidirectional nonlinear characteristics as shown in FIG. 4b and has a large dielectric constant, and in terms of an electrical circuit, it has an equivalent circuit as shown in FIG. 4c. It can be regarded as a parallel circuit of a bidirectional nonlinear element 161 and a capacitor 162, and the amorphous thick film 16 does not conduct direct current. Here, the amorphous semiconductor layer conventionally disclosed in U.S. Pat. It has a high threshold voltage when operating, making it unsuitable for low-voltage operation type electro-optical display panels. In addition, in ordinary electro-optical display panels, the fifth
The illustrated VI characteristic is not required. The amorphous thick film 16 used in this embodiment has an avalanche voltage of approximately 3 volts, and is extremely suitable for a low voltage operation type electro-optical display panel.

Furthermore, when controlling the arrangement of molecules of an electro-optic material, which will be described later, the inward facing surface of the thin film electrode 13 deposited on the front substrate 11 and the amorphous thick film 16 deposited on the back substrate 12 are used. Thin film alignment layers 17, 17 made of polyimide or an organosilane compound are provided on the inward facing surfaces of the substrate. In addition, the back base material 12
The front substrate 1 facing the inward surface of the amorphous thick film 16 and/or the periphery of the back substrate 12 at the periphery thereof.
On the inward surface of the corresponding portion of the thin film electrode 13 of No. 1, a paste containing a binder mixed in frit is screen printed in a frame shape to form a frame-shaped thick film spacer 18.
form.

Next, the front substrate 11 and the back substrate 12 are fired moderately to scatter the binder contained in the spacers 18, and then the front substrate 11 and the back substrate 12 are fired.
2 are laminated and heated again to sinter and hermetically seal them, and later, the gap 19 of the spacer 18 sandwiched between the front substrate 11 and the rear substrate 12 is filled with an electro-optic material to form a matrix type. The configuration of the electro-optic display panel 10 is completed.

Here, the electro-optical substance is a certain type of organic liquid crystal belonging to azoxy compounds, Schiff compounds, ester derivatives, cyanobiphenyl derivatives, cyanotriphenyl derivatives, etc., a mixture of multiple types of organic liquid crystals, or an organic liquid crystal and a liquid crystal state. A mixture of an organic liquid crystal and a dye, etc. can be used. In addition, colloidal suspensions, such as anisotropic acicular crystals such as tungsten oxide, vanadium oxide, and quartz, or layered crystals such as blue lead carbonate and glass pieces, and inorganic fine particles such as herabatite and polyvinylidene fluoride, can also be used. Alternatively, organic particles dispersed in a solvent such as diptylphthalate, diphenyl alcohol, or water, such as those commercially available under the trade name Ballard, can be used. In addition, colloidal liquid in which electrophoretic pigment particles are dispersed in a solvent,
Namely, rutile type titanium dioxide, anatase type titanium dioxide, carbon black, Hansa Yellow G, benzine yellow, Lake Red 4R, phthalocyanine blue, graphite, navy blue, yellow lead, zinc sulfide,
A colloid in which electrophoretic pigment particles such as zinc oxide are dispersed in a solvent such as tetrafluorodibromoethane, trifluorotrichloroethane, trifluoromethane, toluene, benzene, cyclohexane, ethylene chloride, or methane chloride. Electrophoretic display can be performed using a liquid. In such electrophoretic display, a medium dye or the like is often added to the above-mentioned dispersion solvent. In addition, electrochromic substances that reversibly change color due to an electric field, such as n-diheptyl-
4,4′-Biviridium. Dipromite and bis. 4
-diethylamino-2-methylphenyl. 4-
Benzylthiophenylmethane, bis. Organic substances such as diethylamino-2-methylphenylmethane and inorganic substances such as tungsten oxide can also be used in combination.

Such a matrix type electro-optical display panel 10
When an electric field is applied to the thin film electrode 13 and a plurality of arbitrarily selected electrodes, only an alternating current voltage containing no direct current component is applied to the electro-optic material, and characters or figures are generated through the front substrate 11. Images etc. are displayed as a dot matrix. As mentioned above, the electro-optic display panel 10 is completely hermetically sealed, and the thick amorphous film 16 prevents the electro-optic material from leaking out or decomposing, allowing for highly reliable dot matrix display. Become. Further, in such an electro-optical display panel 10, no crosstalk occurs no matter how an electric field is applied.

Next, on the lower surface of the matrix type electro-optical display panel 10, a connecting body 20 having physical elasticity and having very high electrical resistance in the horizontal direction and partially low electrical resistance in the vertical direction is provided. Deploy. The connecting body 2
0, carbon or relatively highly conductive powder such as gold, silver, copper, aluminum, graphite, etc. is spaced between an insulating plate 21 that has a slight physical elasticity and has an appropriate thickness, such as a slightly hard silicone rubber. The conductive parts 22, 22... are arranged in a matrix, and the surface shape and mutual spacing of the conductive parts 22, 22... 15
That is, the shape of the surface of the electrodes and the mutual spacing are approximately matched.

An LSI circuit 30 is arranged on the bottom surface of the connection body 20. The LSI circuit 30 includes, for example, FET switching arrays 32, 32, . . . on the upper surface of an n-type silicon substrate.
are arranged in a matrix. The switching arrays 32, 32, . . . correspond to the electrodes 15, 15, .
It includes transmission gates 321 and 322 consisting of an FET and an N-channel FET, and a terminal 323.
The address pulse input to the terminal 324 outputs an alternating current voltage modulated by the clock pulse input to the terminal 325 to the terminal 325. This AC voltage is
It leads to terminals 33, 33... at the upper end of the FET switching arrays 32, 32.... In addition, terminal 3
It is preferable that the shape of the surfaces and the mutual spacing of the electrodes 3, 33, .

Thus, when the dot matrix type electro-optic display panel 10 and the LSI circuit 30 are superposed on each other via the above-mentioned connector 20, a display corresponding to the address pulse can be displayed on the electro-optic display panel 10. Generally, the larger the area of the LSI circuit 30, the more likely it is that electrical defects will occur locally, and the manufacturing yield will decrease in proportion to the surface area, and the cost will increase significantly. However, if the laminated structure shown in this embodiment is adopted, even if the display area of the electro-optical display panel 10 is considerably large, as shown in FIG. 7, LSI circuits 30, 30, . It is also possible to drive a common electro-optical display panel 10 by arranging a plurality of them in parallel vertically and horizontally. Further, in this embodiment, the dot matrix type electro-optical display panel 10 or the LSI circuits 30, 30
If a defect occurs in either one or a portion of the parts, it is only necessary to replace the part, which makes maintenance extremely easy, and has many advantages.

In this embodiment, a matrix-type electro-optical display panel and its device have been described, but it goes without saying that the present invention can also be applied to devices other than the matrix-type, such as an electro-optic display panel that displays characters in segments and its device.

As detailed above, in the present invention, _{SiO 2 and} B ₂ O ₃ ,
Borosilicate glass made from materials such as Na ₂ O is heated once to separate its phases, and then treated with strong acid to dissolve and separate phases other than the Si-O skeleton. Porous glass blocks are embedded in a matrix. Since the conductive material is impregnated into the plate-shaped base material that is then heated and fired, there is no risk of the conductive material penetrating into areas other than porous areas, resulting in an extremely reliable hermetically sealed matrix-type electro-optical display panel. It has excellent features such as being easy to configure and easily providing a matrix display with a considerably large display area by combining with a plurality of LSI circuits with a relatively small area.

[Brief explanation of drawings]

FIG. 1 is a perspective view of a matrix-type electro-optical display device according to the present invention, FIG. A perspective view showing the manufacturing method, FIG.
is a graph showing the electrical characteristics of the thick film, c is its equivalent circuit diagram, Fig. 5 is a graph showing the electrical characteristics of the amorphous semiconductor layer, and Fig. 6 is an equivalent circuit diagram of a switching array in an LSI circuit. , FIG. 7 is a sectional view showing the relationship between a matrix-type electro-optical display device with a large surface area and an LSI circuit. 11...Front substrate, 12...Back base material, 10...
...Display panel, 13...Thin film electrode, 14...Block, 15...Porous glass block or electrode, 16...Thick film, 18...Spacer, 32...
FET switching array, 30...LSI circuit, 3
3...Terminal.

Claims (1)

[Scope of Claims] 1. A display panel comprising a pair of front substrate and rear substrate facing each other, wherein the front substrate has a transparent thin film electrode coated on at least the inner surface of a transparent glass plate. , the above-mentioned back substrate is a glassy block mainly composed of SiO and SiO ₂ , B ₂ O ₃ ,
A porous glass block made by heating borosilicate glass made from Na ₂ O etc. to separate the phases and then treating it with strong acid to dissolve and separate phases other than the Si-O skeleton was buried in a matrix. Afterwards, they were heated and fired to form a plate-like structure, and a plurality of electrodes were buried in the porous glass block.The inner surface of the plate-like base material was made of _SiO2 as a main component, which has a high dielectric constant and is electrically conductive. An amorphous thick film having bidirectional nonlinear characteristics is deposited, and a frame-shaped thick film spacer is provided on the lower surface of the thin film electrode of the front substrate and/or the upper surface of the amorphous thick film of the rear substrate. an electro-optic display panel in which the front substrate and the back substrate are properly fired, then laminated and sealed together, and the gap formed by the front substrate and the back substrate facing each other is filled with an electro-optic material. . 2. In a display panel comprising a pair of front substrate and back substrate facing each other, the front substrate has a transparent thin film electrode coated on at least the inward surface of a transparent glass plate, and the back substrate is a glassy block mainly composed of SiO, SiO ₂ , B ₂ O ₃ , Na ₂ O
A porous glass block made by heating borosilicate glass made of materials such as borosilicate glass to separate its phases, and then treating it with strong acid to dissolve and precipitate phases other than the Si-O skeleton is buried in a matrix, and then heated and fired. After that, a plurality of electrodes were buried in the porous glass block portion, and the inward surface of the plate-shaped base material was made of SiO ₂ as a main component and had a high dielectric constant and was electrically bidirectionally non-conductive. an amorphous thick film having linear characteristics is deposited, a frame-shaped thick film spacer is provided on the lower surface of the thin film electrode of the front substrate and/or the upper surface of the amorphous thick film of the rear substrate; The front substrate and the back substrate are suitably fired, then laminated and sealed together, and the gap formed by the front substrate and the back substrate facing each other is filled with an electro-optic material to form a single matrix type. An electro-optical display panel and one or more LSI circuits in which a switching array is arranged in a matrix or the like are stacked together via a connector, and the terminals of the switching array stacked with the matrix-type electro-optic display panel are An electro-optic display device in which the surface shape and the mutual gap substantially match the surface shape and the mutual gap of the electrodes of the matrix-type electro-optic display panel, and the switching array and the electrode correspond one-to-one. .