WO1999065010A1

WO1999065010A1 - Display device

Info

Publication number: WO1999065010A1
Application number: PCT/JP1999/003090
Authority: WO
Inventors: Ritsuo Inaba
Original assignee: Matsushita Electric Industrial Co., Ltd.
Priority date: 1998-06-10
Filing date: 1999-06-09
Publication date: 1999-12-16

Abstract

A display device (1) comprises a first substrate (10), a second substrate (15) opposed to the first substrate (10), and a functional material layer (12) between the first substrate (10) and the second substrate (15). A plurality of signal electrodes (11) connected with a common signal line are formed on the first substrate (10). Scanning electrodes (13) are formed on the second substrate (15) in such a manner that they are opposed to the signal electrodes (11).

Description

Description Display device Technical field

The present invention relates to a display device, and more particularly to a display device suitable for realizing a large-area or high-definition screen. Background art

Point scanning and line scanning are known as methods for scanning a flat display.

Point scanning is a method of scanning a plane with points. For example, by scanning a light emitting point like a CRT, the afterglow can be used to emit light over the entire plane. Line scanning is a method of scanning a plane line by line. For example, by sequentially repeating an operation of causing a plurality of light emitting elements arranged in a certain row to emit light and then causing a plurality of light emitting elements arranged in the next row to emit light, the entire plane can be made to emit light.

In order to realize a large-area or high-definition screen, it was necessary to increase the light-emitting area and increase the density of light-emitting lines. For that purpose, it was necessary to increase the energy of the light emitting part in either the point scan or the line scan. However, increasing the energy of the light emitting section causes various problems such as heat generation, signal leakage, voltage increase, and light emission saturation.

In addition, in order to realize a large-area or high-definition screen, it was necessary to increase the number of scanning lines in either point scanning or line scanning. However, increasing the number of scanning lines causes a problem in that the response speed of the display becomes slow. Conventionally, a display device having a simple matrix structure and an active Display devices having a tricks structure are known. With the current technology, it is said that there is a limit in realizing a large-area or high-definition screen using a display device with a simple matrix structure for the following reasons.

1. Limit of light emitting area of display device

2. Limits of emission size and device density

3. Luminance

4. Luminous efficiency

5. Cross between pixels! K

For this reason, active matrix display devices have become the mainstream display devices for realizing large-area or high-definition screens. However, an active matrix display device requires elements such as a switching element and a sample-and-hold element for each pixel, so the structure is more complicated than a simple matrix display device, and costs increase. There is a problem that.

An object of the present invention is to provide a display device that realizes a large-area or high-definition screen. In particular, an object of the present invention is to provide a display device that realizes a large-area or high-definition screen at low cost by using a simple matrix structure. Disclosure of the invention

The display device of the present invention includes a first substrate, a second substrate facing the first substrate, and a functional material layer provided between the first substrate and the second substrate, and a common signal. A plurality of signal electrodes driven by a voltage are formed on the first substrate, and a scan electrode is formed on the second substrate so as to face the plurality of signal electrodes. The above object is achieved.

The first substrate may be a transparent substrate, and the signal electrode may be a transparent electrode. The second substrate may be a transparent substrate, and the scanning electrode may be a transparent electrode. Another display device according to the present invention includes a first substrate, a second substrate facing the first substrate, and a functional material layer provided between the first substrate and the second substrate. A plurality of signal electrode groups are formed on the first substrate, each of the plurality of signal electrode groups includes a plurality of signal electrodes arranged in a predetermined first direction, and a plurality of scan electrode groups are provided. The plurality of scan electrode groups are formed on the second substrate so as to face the plurality of signal electrode groups, each of the plurality of scan electrode groups includes a plurality of scan electrodes extending in a predetermined second direction, and the plurality of scan electrodes A scan voltage is applied to the plurality of scan electrodes selected from the group, and a signal voltage is applied to the plurality of signal electrodes included in one of the plurality of signal electrode groups. Thereby, the above object is achieved.

The first substrate may be a transparent substrate, and the signal electrode may be a transparent electrode. The second substrate may be a transparent substrate, and the scanning electrode may be a transparent electrode. The display device further includes a plurality of signal lines formed on the first substrate, and one of the plurality of signal lines is included in one of the plurality of signal electrode groups. It may be connected to the plurality of signal electrodes.

The plurality of signal lines may be provided between adjacent signal electrodes.

A pad is formed at a position on the first substrate corresponding to a gap between adjacent scan electrodes of the plurality of scan electrodes, and one of the plurality of signal lines is taken out through the pad. Is also good.

The sheet resistance of the signal electrode may be in the range of 100 km 2 to 10 km 2 Z cm 2.

The signal electrode may be made of a single material of tin oxide or zinc oxide or a mixed material thereof.

The signal line may be made of a binary alloy material containing aluminum or copper.

Another display device of the present invention includes: a substrate having a multilayer structure; A plurality of first electrodes formed thereon, a functional material layer formed on the plurality of first electrodes, and a plurality of transparent second electrodes formed on the functional material layer Each of the first electrode and the second electrode is electrically connected to a wiring provided in the substrate having the multilayer structure. Thereby, the above object is achieved. Another display device of the present invention includes: a substrate having a first surface and a second surface facing the first surface; a plurality of first electrodes formed on the first surface of the substrate; A functional material layer formed on the plurality of first electrodes, and a plurality of transparent second electrodes formed on the functional material layer; and a voltage applied to the plurality of first electrodes. All of the voltages applied to the plurality of second electrodes are supplied from the second surface of the substrate. Thereby, the above object is achieved.

Means for driving the plurality of first electrodes and the plurality of second electrodes may be provided on the second surface of the substrate.

The functional material layer may be a liquid crystal layer.

The functional material layer may be an organic electroluminescence light emitting layer. The functional material layer may be an inorganic electorescence luminescent layer. The substrate may be made of a flexible material.

The thickness of the display device from the second surface of the substrate to the second electrode may be between 50 microns and 150 microns. BRIEF DESCRIPTION OF THE FIGURES

FIG. 1 is a diagram illustrating a structure of a display device 1 according to a first embodiment of the present invention. FIG. 2 is a plan view of the first substrate 10 shown in FIG.

FIG. 3 is a plan view of the second substrate 15 shown in FIG.

FIG. 4 shows an improved arrangement of the signal lines provided on the first substrate 10.

FIG. 5 is a plan view showing the arrangement of a plurality of signal electrodes 11 formed on the first substrate 10. FIG. 6 is a diagram showing a structure of the display device 1a according to the first embodiment of the present invention.

FIG. 7 is a diagram illustrating a structure of the display device 2 according to the second embodiment of the present invention. FIG. 8 is a diagram showing a cross section of the display device 2 along the line AB shown in FIG.

FIG. 9 is a diagram showing the structure of the back surface of the substrate 211 shown in FIG.

FIG. 10 is a diagram showing an example of the multilayer structure of the substrate 211.

FIG. 11 is a diagram showing an example in which an active matrix element is formed on the back surface of the substrate 211. FIG.

FIG. 12 is a diagram showing a circuit configuration of the circuit element shown in FIG. BEST MODE FOR CARRYING OUT THE INVENTION

(Embodiment 1)

FIG. 1 shows the structure of the display device 1 according to the first embodiment of the present invention.

The display device 1 includes a first substrate 10, a second substrate 15 facing the first substrate 10, and a functional material layer 1 provided between the first substrate 10 and the second substrate 15. Including 2. The display device 1 has a simple matrix structure.

A plurality of signal electrodes 11 are formed on the first substrate 10. The plurality of scanning electrodes 13 are formed on the second substrate 15 so as to face the plurality of signal electrodes 11. A signal voltage is applied to the signal electrode 11. A scanning voltage is applied to the scanning electrode 13. The pixel region of the functional material layer 12 at a position corresponding to the signal electrode 11 to which the signal voltage is applied and the scan electrode 13 to which the scanning voltage is applied is driven.

The first substrate 10 may be a transparent substrate, and each of the plurality of signal electrodes 11 may be a transparent electrode. In this case, the output light from the display device 1 is output from the transparent first substrate 10 via the transparent signal electrode 11. Alternatively, the second substrate 15 is a transparent substrate, and each of the plurality of scanning electrodes 13 is a transparent electrode. You can use it. In this case, the output light from the display device 1 is output from the transparent second substrate 15 via the transparent scanning electrode 13.

The transparent substrate is, for example, a glass substrate or a plastic substrate. The opposite substrate facing the transparent substrate is made of an electrode holding material.

The plurality of signal electrodes 11 are electrically connected to the signal lines 16-1 formed on the first substrate 10. Similarly, a plurality of signal electrodes 11 are electrically connected to signal lines 16-2, 16-3, 16-4,. Each of the signal lines 16-1, 16-2, 16-3, 16-4,... Is used to apply a signal voltage to the plurality of signal electrodes 11.

The functional material layer 12 can be made of various materials. The present invention can be applied to any type of display device by changing the material of the functional material layer 12. For example, when the present invention is applied to a liquid crystal display device, a liquid crystal layer may be used as the functional material layer 12. When the present invention is applied to an organic light emitting device, an organic electroluminescent light emitting layer may be used as the functional material layer 12. When the present invention is applied to an inorganic light emitting device, an inorganic electorescence luminescent layer may be used as the functional material layer 12.

Note that, when the display device 1 is a liquid crystal display device, further configurations such as a deflection filter and a color filter are necessary, but these configurations are omitted in FIG.

FIG. 2 is a plan view of the first substrate 10. A plurality of signal electrodes 1.

1 is arranged. Each of the plurality of signal electrodes 11 has a size corresponding to a pixel. For example, the size of the signal electrode 11 may match the size of the pixel, or may be larger than the size of the pixel. The size of the pixel is, for example, 100 micron angles. Each of the plurality of signal electrodes 11 is arranged at a position corresponding to a pixel.

The plurality of signal electrodes 11 formed on the first substrate 10 form a plurality of signal electrode groups. It is classified. In the example shown in FIG. 2, the plurality of signal electrodes 11 are divided into three signal electrode groups lla, 11b, and 11c. However, the number of signal electrode groups is not limited to three. The plurality of signal electrodes 11 can be divided into an arbitrary number of signal electrode groups. The signal electrode group 11a includes a plurality of signal electrodes 11 arranged in the X direction (for example, 64 signal electrodes 11-1-11) and a plurality of signal electrodes 1 arranged in the X direction. 1— 1

2 (for example, 64 signal electrodes 1 1 1 1 2) and a plurality of signal electrodes 1 1 1 13 arranged in the X direction (for example, 64 signal electrodes 1 1 13), and an array in the X direction A plurality of signal electrodes 111-114 (for example, 64 signal electrodes 111-114). The plurality of signal electrodes 11-11 to 11-14 are arranged adjacent to each other in the Y direction.

Note that the X direction is the direction of the arrow X shown in FIG. The Y direction is the direction of the arrow Y shown in FIG. The X direction and the Y direction are typically orthogonal, but need not be.

The configuration of the signal electrode group 11b and the signal electrode group 11c is the same as the configuration of the signal electrode group 11a.

In FIG. 2, for simplicity, only signal electrodes for four columns are shown in each signal electrode group, and signal electrodes for the fifth and subsequent columns are omitted. In each signal electrode group, the number of signal electrodes arranged in the Y direction can be any number.

The signal line 16-1 includes three signal lines 16-11 to 16-31. The signal lines 16 11-16-31 are provided adjacent to the plurality of signal electrodes 11-11-11-31. The signal line 16-11 is electrically connected to a plurality of signal electrodes 11-1-11 included in the signal electrode group 11a. The signal lines 16-21 are electrically connected to the plurality of signal electrodes 11-21 included in the signal electrode group 11b. The signal lines 16-31 are electrically connected to a plurality of signal electrodes 11-31 included in the signal electrode group 11c.

The signal lines 16-12 to 16-32 are provided between the plurality of signal electrodes 11-11 and L 1-31 and the plurality of signal electrodes 11-12 to 11-32. Similarly, The signal lines 16-13 to 16-33 and the signal lines 16-14 to 16-34 are also provided between the signal electrodes adjacent in the Y direction.

FIG. 3 is a plan view of the second substrate 15. A plurality of scan electrodes 13 are arranged on the second substrate 15. Since the scanning electrode 13 is formed on the back side of the paper surface of FIG. 3, the scanning electrode 13 is shown by a broken line in FIG.

The plurality of scan electrodes 13 formed on the second substrate 15 are divided into a plurality of scan electrode groups. In the example shown in FIG. 3, the plurality of scan electrodes 13 are divided into three scan electrode groups 13a, 13b, and 13c so as to correspond to three signal electrode groups lla, llb, and 11c, respectively. ing. However, the number of scan electrode groups is not limited to three. The plurality of scan electrodes 13 can be divided into an arbitrary number of scan electrode groups corresponding to the number of signal electrode groups.

Scan electrode group 13a includes a plurality of scan electrodes 13 (for example, 64 scan electrodes 13) arranged in the X direction. Each of the plurality of scanning electrodes 13 extends in the Y direction.

The configuration of scan electrode group 13b and scan electrode group 13c is the same as the configuration of scan electrode group 13a.

In FIG. 3, for simplicity, only three of the plurality of scan electrodes 13-11 to 13-13 of the plurality of scan electrodes 13 included in the scan electrode group 13a are shown, and are included in the scan electrode group 13b. Only three scan electrodes 13-21 to 13-23 of the plurality of scan electrodes 13 shown are shown, and three scan electrodes 13-31 to three of the plurality of scan electrodes 13 included in the scan electrode group 13c are shown. : Only 13-33 is shown.

Hereinafter, the operation of the display device 1 will be described with reference to FIGS. In the first scanning period, scan electrodes 13-11 included in scan electrode group 13a, scan electrodes 13-21 included in scan electrode group 13b, and scan electrodes included in scan electrode group 13c Scan voltages are applied to 13-31.

Next, in the second scanning period, the scanning electrodes 13- A scan voltage is applied to 12, scan electrodes 13 to 22 included in scan electrode group 13b, and scan electrodes 13 to 32 included in scan electrode group 13c.

Next, in the third scanning period, scan electrodes 13-13 included in scan electrode group 13a, scan electrodes 13-23 included in scan electrode group 13b, and scan electrode group 13c The scanning voltage is applied to the scanning electrodes 13 to 33 included in the scanning.

As described above, in each scanning period, the scanning electrodes are driven such that the scanning voltage is simultaneously applied to the plurality of scanning electrodes selected one by one from the plurality of scanning electrode groups. Such driving is controlled by a scan electrode driving circuit (not shown). A plurality of signal electrodes 11-1-11, 11-1-12, 11-11, 11-14 included in the signal electrode group 11a have signal lines 16-11, 16-12, respectively. , 16—13, 16-14, the signal voltage is applied. A plurality of signal electrodes included in the signal electrode group 1 1 b 1 1 1 2 1, 1 1 -22, 1 1 -23, 1 1 -24 are respectively connected to signal lines 16 -21, 16 -22, 1 Signal voltage is applied via 6−23, 16−24. A plurality of signal electrodes included in the signal electrode group 1 1 c 1 1 1 3 1, 1 1 1 32, 1 1-33, 1 1-34 have signal lines 16-31, 16-32, 16 respectively. — Signal voltage is applied via 33, 16-34.

The signal voltage value is updated in synchronization with the change in the running period. The application of the signal voltage to the signal electrodes is controlled by a signal electrode drive circuit (not shown).

The pixel region of the functional material layer 12 sandwiched between the scanning electrode to which the scanning voltage is applied and the signal electrode to which the signal voltage is applied is driven. Therefore, in each scanning period, three pixel regions are simultaneously driven. For example, when the functional material layer 12 is an organic electroluminescent light emitting layer, three pixel regions emit light simultaneously in each scanning period.

For example, in the first scanning period, the functional material sandwiched between the scanning electrode 13-11 and the signal electrode 11-1 1 1 1-12.1 1-1 3, 1 1-14, Pixel area of layer 1 2, scan electrode 13-21, signal electrode 11-21, 1 11-22, 1 1- The pixel area of the functional material layer 12 sandwiched between 23, 1 1—24,..., The scanning electrode 13—31, and the signal electrode 11—31, 1 1—32 The pixel region of the functional material layer 12 sandwiched between 1 — 3 3, 1 1 — 3 4, and · · · emits light.

As described above, by simultaneously driving a plurality of pixel regions, a large-area or high-definition screen can be realized using a display device having a simple matrix structure.

Note that a signal line for supplying a signal voltage to the signal electrode 11 does not necessarily need to be arranged between adjacent signal electrodes 11.

FIG. 4 shows an improved arrangement of the signal lines provided on the first substrate 10. An extraction pad 31 is provided at a position on the first substrate 10 corresponding to a gap between the adjacent scanning electrodes 13. One signal line is drawn from each of the extraction pads 31 along the gap between the adjacent scanning electrodes 13. The signal line drawn from the extraction pad 31 is connected to the extraction electrode 32. The extraction electrode 32 is provided on the second substrate 15 at a position corresponding to the scanning electrode 13. The extraction electrodes 32 can be connected to each other by, for example, a mechanical stress method.

According to the arrangement shown in FIG. 4, only one signal line needs to be provided between adjacent signal electrodes. Thus, it is possible to avoid the complexity of passing a plurality of signal lines between signal electrodes (or light emitting pixels).

Note that, depending on the display device, the scanning electrode 13 can be provided on the first substrate 10. In this case, an extraction pad for the scanning electrode 13 may be provided on the first substrate 10 and a scanning voltage may be supplied to the scanning electrode 13 via the extraction pad.

Note that the plurality of signal electrodes 11 formed on the first substrate 10 does not necessarily need to be divided into a plurality of signal electrode groups.

FIG. 5 is a plan view showing the arrangement of a plurality of signal electrodes 11 formed on the first substrate 10. Each of the plurality of signal electrodes 11 has a size corresponding to a pixel. For example, the size of the signal electrode 11 may match the size of the pixel, or may be larger than the size of the pixel. The size of the pixel is, for example, 100 microns square. Further, each of the plurality of signal electrodes 11 is arranged at a position corresponding to a pixel. In the example shown in FIG. 5, a plurality of signal electrodes 111 are arranged in the X direction, and each of the plurality of signal electrodes 111 is connected to a common signal line 161-1. Similarly, a plurality of signal electrodes 1 1 2, 1 1-3, 1 1 4 are respectively arranged in the X direction. Each of the plurality of signal electrodes 11-2 is connected to a common signal line 16-2. Each of the plurality of signal electrodes 11-3 is connected to a common signal line 16-3. Each of the plurality of signal electrodes 111 is connected to a common signal line 16-4.

In FIG. 5, for simplicity, only the signal electrodes for four columns are shown, and the signal electrodes for the fifth and subsequent columns are omitted. The number of signal electrodes arranged in the Y direction on the first substrate 10 can be any number.

The first substrate 10 on which the plurality of signal electrodes 11 are arranged as shown in FIG. 5 can be used as the first substrate 10 in the display device 1 shown in FIG. That is, the second substrate 15 is provided so as to face the first substrate 10, and the functional material layer 12 is provided between the first substrate 10 and the second substrate 15.

A plurality of scan electrodes 13 are formed on the second substrate 15. Each of the plurality of scanning electrodes 13 extends in the Y direction. A scanning voltage is selectively applied to one of the plurality of scanning electrodes 13. A signal voltage is applied to each of the signal lines 16-1, 16-2, 16-3, 16-4,. As a result, a common signal voltage is applied to a plurality of signal electrodes 11 commonly connected to one signal line. The pixel region of the functional material layer 12 at a position corresponding to the signal electrode 11 to which the signal voltage is applied and the scan electrode 13 to which the scanning voltage is applied is driven.

As described above with reference to FIG. 1, the first substrate 10 may be a transparent substrate, and each of the plurality of signal electrodes 11 may be a transparent electrode. In this case, Output light from the ray device 1 is output from the transparent first substrate 10 via the transparent signal electrode 11. Alternatively, the second substrate 15 may be a transparent substrate, and each of the plurality of scanning electrodes 13 may be a transparent electrode. In this case, the output light from the display device 1 is output from the transparent second substrate 15 via the transparent scanning electrode 13.

Note that the scanning electrode 13 may have a size corresponding to a pixel, like the signal electrode 11. In this case, the plurality of scan electrodes 13 are connected to one common scan line, and a common scan voltage is applied to the plurality of scan electrodes 13 connected to the common scan line.

FIG. 6 shows the structure of the display device 1a according to the first embodiment of the present invention. The display device 1a has a structure suitable for an organic light emitting device.

The display device 1a includes a metal substrate 51 and an insulating layer 52 formed on the metal substrate 51. By removing a portion corresponding to each pixel from the insulating layer 52, the metal substrate 51 can be used as a force source electrode. An organic functional material layer is formed on the force source electrode, and a transparent electrode is formed on the organic functional material layer. Output light is extracted from the transparent electrode.

As the metal material of the metal substrate 51, aluminum (including an aluminum-lithium alloy or the like), stainless steel, or the like can be used. On the metal substrate 51, an electron transport layer and a hole transport layer are formed as organic functional material layers. A transparent electrode is formed on the hole transport layer. The transparent electrode is produced by a method such as vapor deposition sputtering.

Since organic light emitting devices cannot avoid the generation of heat that does not depend on light emission at each part of light emission, the problem of heat must always be considered when increasing the area. By introducing a metal substrate, advantages such as better heat radiation conditions, a thinner and more flexible light emitting element, and a lower moisture permeability are obtained. Note that a metal substrate may be used as the force source electrode, or a cathode electrode may be formed on the metal substrate. An insulating film may be provided on a metal substrate, and wiring may be formed on the insulating film.

A glass substrate that can be used as a transparent substrate can be, for example, 0.7 mm thick soda glass. A diffusion prevention film is formed on the soda glass to prevent diffusion of ions such as soda, and a transparent electrode is formed on the diffusion prevention film. The transparent electrode is, for example, an oxide of indium tin having a thickness of 0.05 micron.

The signal line is made of, for example, aluminum. The signal lines can be formed to have a line width of 2 microns and a thickness of 1 micron.

The line width of one signal line can be 2 microns, and the gap between signal lines can be 2 microns. In this case, the width required to provide three signal lines in parallel is

(2 + 2) micron X 3 lines + 2 micron = 14 micron

Becomes Thus, even if three signal lines are provided in parallel, the width of the three signal lines is sufficiently small, and there is no possibility that the light emitting area is limited by those signal lines.

The width of the scanning electrode is wider than the width of the signal line. Therefore, the scanning electrode can be easily manufactured as compared with the signal line. A relatively large current corresponding to one line needs to flow through the scanning electrode. The scanning electrode is made of a metal such as aluminum. The width of the scanning electrode is determined according to the size of the pixel. For example, if the pixel size is 0.1 mm square, the width of the scan electrode may be 0.1 mm.

When the display device 1, 1a is an organic light emitting device, the selection of the material of the scanning electrode is important. In this case, an alloy of aluminum and lithium or an alloy of magnesium and silver is generally used as a material of the scanning electrode. In the present embodiment, the scanning electrode is manufactured using a metal mask by a resistance heating method using aluminum-lithium alloy as a material.

In a conventional display device, it was necessary to keep the resistance of the transparent electrode as low as possible in order to reduce the voltage loss in the lead wire as much as possible. this Therefore, a resistance value that is orders of magnitude smaller than the resistance value required for the function of the original pixel portion has been required. As a result, it was necessary to determine the structure and material of the transparent electrode at the expense of other negative factors in order to reduce the resistance of the transparent electrode.

Specifically, it was necessary to limit the material of the transparent electrode to an indium tin oxide compound or to limit the thickness thereof. Such limitations have caused problems such as increased power loss, crosstalk, and signal delay. On the other hand, in the display device of the present invention, since the size of the transparent electrode can be made to correspond to the size of the pixel, it is not necessary to suppress the resistance value of the transparent electrode. This is because, according to the display device of the present invention, the length of the current path flowing through the transparent electrode can be significantly shortened as compared with the related art. For example, when the size of the transparent electrode is 0.1 mm square, the length of the current path flowing through the transparent electrode is only 0.1 mm. This makes it possible to freely select the material of the transparent electrode and to reduce the thickness of the transparent electrode by two orders of magnitude.

By reducing the thickness of the transparent electrode, the material cost of the transparent electrode can be reduced. In particular, when an indium electrode is used as the transparent electrode, the cost of the transparent electrode can be reduced to less than one tenth of the total cost. This leads to reduced material processing costs, reduced processing time for sputtering and other processes, and improved reliability.

The material of the transparent electrode and the material of the signal line affect the life of the display device. In general, when electricity is passed through a material, the ionization of the material and the movement of a substance (so-called migration) hinder the maintenance of the characteristics of the display device. As described above, in the present invention, the material of the transparent electrode can be freely selected. Therefore, by appropriately selecting the material of the transparent electrode and the material of the signal line, it is possible to eliminate the influence of characteristic deterioration due to migration. This makes it possible to extend the life of the display device.

If the resistance value of the transparent electrode is set to a relatively high value, the surface resistance of the transparent electrode The resistance (electrical resistance per 1 cm width and 1 cm distance) is preferably from 100 ohm Z square centimeter to 10 kiloohm square centimeter.

The transparent electrode may be made of a single material such as tin oxide or zinc oxide or a mixed material thereof.

The signal line may be made of a binary alloy material containing aluminum or copper. For example, the material of the signal line can be a binary alloy material of aluminum mixed with other metals (eg, copper, tin, silver, nickel, zinc, etc.). Alternatively, the material of the signal line may be a binary alloy material in which copper is mixed with a small amount of another metal (eg, aluminum, tin, nickel, silver, zinc, or the like).

(Embodiment 2)

FIG. 7 shows a structure of the display device 2 according to the second embodiment of the present invention.

The display device 2 includes a substrate 2 1 1, a plurality of force source electrodes 2 1 2 formed on the substrate 2 1 1, and a functional material layer formed on a plurality of cut electrodes 2 1 2 2 13 and a plurality of transparent anode electrodes 2 15 formed on the functional material layer 2 13. The display device 2 has a simple matrix structure. Both the voltage applied to the plurality of force source electrodes 2 12 and the voltage applied to the plurality of anode electrodes 2 15 form the force source electrode 2 12 on the surface of the substrate 211. It is supplied from the surface opposite to the surface on which it is placed (hereinafter referred to as the back surface of the substrate 211). Thus, the voltage (negative power supply voltage) applied to the force electrode 2 121 and the voltage (positive power supply voltage) applied to the anode electrode 2 15 are supplied from the back surface of the substrate 2 1 1 By doing so, it is not necessary to dispose an extraction electrode for extracting those voltages on the side surface of the display device 2. This makes it possible to tile the display device 2 in two dimensions.

For example, a display device having 3 NX 3 M pixels can be configured by arranging a total of 9 display devices 2 each having 3 NXM pixels each in 3 rows and 3 columns. This enables a simple matrix structure display Using a device, a large screen or a high-resolution screen can be realized. In addition, a voltage (negative power supply voltage) applied to the force source electrode 211 and a voltage (positive power supply voltage) applied to the anode electrode 215 are supplied from the back surface of the substrate 211. This can prevent a decrease in the aperture ratio.

Furthermore, since a substrate for holding the anode electrode (transparent electrode) 215 is not required, the thickness of the laminated structure of the display device 2 from the back surface of the substrate 211 to the anode electrode 215 should be reduced. Can be. For example, the thickness can be between 50 microns and 150 microns.

Although FIG. 7 shows that the plurality of force source electrodes 2 12 and the functional material layer 2 13 are spatially separated, this is for convenience of explanation. Actually, the plurality of force source electrode layers 21 and the functional material layers 21 are formed so as to be in contact with each other. Similarly, FIG. 7 shows that the functional material layer 2 13 and the plurality of anode electrodes 2 15 are spatially separated from each other, but this is for convenience of explanation. Actually, the functional material layer 2 13 and the plurality of anode electrodes 2 15 are formed so as to be in contact with each other.

FIG. 8 shows a cross section of the display device 2 along the line A—B shown in FIG. FIG. 9 shows the structure of the back surface of the substrate 211 shown in FIG.

The force source electrode 2 12 is electrically connected to the wiring 2 19 a provided on the back surface of the substrate 2 1 1 via the lead-in line 2 18 a. The lead-in line 218 a is formed to penetrate the substrate 211. The wiring 219 a is electrically connected to a force sword electrode drive circuit 220 a for driving the force sword electrode 2 12. The force source electrode drive circuit 220 a is provided on the back surface of the substrate 211. As a result, the voltage output from the power source electrode drive circuit 220a is supplied to the power source electrode 212 from the back surface of the substrate 211 via the lead-in line 218a.

The anode electrode 215 is electrically connected to the wiring 219 b provided on the back surface of the substrate 211 via the lead-in wire 218 b. The lead-in line 2 18 b is the organic material layer 2 1 3 and the substrate 211 are formed to penetrate. In particular, the lead-in wire 2 18 b is formed so as to pass between adjacent force source electrodes 2 12 formed on the substrate 2 1 1. The wiring 219 b is electrically connected to an anode electrode driving circuit 220 b for driving the anode electrode 215. The anode electrode drive circuit 220 b is provided on the back surface of the substrate 211. As a result, the voltage output from the anode electrode driving circuit 220b is supplied from the back surface of the substrate 211 to the anode electrode 215 via the introduction line 218b.

In addition, instead of the force electrode drive circuit 220 a and the anode electrode drive circuit 220, a single drive circuit for driving the force electrode electrode 212 and the anode electrode 215 is provided on the back of the substrate 211. May be provided. The wiring 219 a and the wiring 219 b are connected to the single driving circuit.

Note that the anode electrode 2 15 may be taken out from the front surface of the light emitting element instead of the back surface of the substrate 211.

When a voltage is applied between the force source electrode 2 12 and the anode electrode 2 15, the functional material at the position where the force electrode 2 12 intersects with the anode electrode 2 15 The pixel area of the layer 2 13 is driven. For example, when the functional material layer 2 13 is an organic electroluminescent light emitting layer, a pixel region at a position where the force electrode 2 12 intersects with the anode 2 15 emits light.

The substrate 211 is made of a resin, ceramic, or metal material, or a composite material of these materials. Ceramics and metals are superior in terms of heat conduction. Ceramics are insulative, and metals are conductive, so it is necessary to design the board by taking advantage of their characteristics. On the other hand, when an organic material is used as the substrate material, the heat conduction is poor, but the advantages of easy device configuration and easy input / output of electrodes are advantages.

When a metal substrate is used as the substrate 2 11, an insulating layer is provided on the metal surface so that the substrate 2 1 1 Can be handled. For example, when the substrate 211 is an aluminum substrate, an insulating layer such as aluminum oxalate may be provided on the surface of the aluminum. It is preferable that the substrate 211 has flexibility. For example, by bonding a polyimide and a copper foil, a flexible substrate 211 can be manufactured. Alternatively, a flexible substrate 211 may be manufactured by bonding a glass epoxy resin and a copper foil. It is preferable that the material of the substrate 211 is a material that can accurately perform a hole forming process at a pixel pitch. From such a viewpoint, polyester, aramide, and various other general-purpose films can be widely used as the material of the substrate 211.

The force source electrode 2 1 2 is made of, for example, A 1 Li alloy or Mg Ag alloy,

It is formed to have a thickness of 150 Å. The anode electrode (transparent electrode) 215 is made of, for example, ITO, {η}, or Au. A passivation film 216 is formed on the anode electrode 215, and an outer cover 217 is formed on the passivation film 216.

The substrate 211 may have a single-layer structure, but preferably has a multilayer structure. This is because signal lines and scanning lines can be formed separately in different layers of a multilayer structure. Each layer in the multilayer structure is made of resin, ceramic or metal.

FIG. 10 shows an example of the multilayer structure of the substrate 211. In the example shown in FIG. 10, the intermediate wiring layers 2 23 a and 22 3 b are formed inside the substrate 2 11, and the rear wiring layers 2 19 a, 2 19 b is formed.

One or two of signal lines, scanning lines, ground lines, power lines, and the like are formed on the intermediate wiring layers 222 a and 222 b. For example, by forming signal lines on the intermediate wiring layer 223a and forming scanning lines on the intermediate wiring layer 223b, the signal lines and the scanning lines are separated inside the substrate 211. Can be. On the back wiring layers 2 19 a and 2 19 b, other lines not formed on the intermediate wiring layers 2 2 3 a and 2 23 b may be formed. You.

In particular, when an active matrix element is formed on the substrate 211, it is preferable that the substrate 211 has a multilayer structure. Active matrix elements require power supply lines.

Needless to say, the substrate 211 can have a multilayer structure of three or more layers. In particular, two or more intermediate wiring layers may be provided inside the substrate 211.

When the substrate 211 has a multilayer structure, one or both of the force source electrode driving circuit 220 a and the anode electrode driving circuit 220 b shown in FIG. It may be formed inside. For example, the power source electrode drive circuit 220 a can be electrically connected to the power source electrode 212 via an intermediate wiring layer 222 a provided inside the substrate 211. The anode electrode driving circuit 222 can be electrically connected to the anode electrode 215 via an intermediate wiring layer 223b provided inside the substrate 211. When all the circuits required to drive the force source electrode 2 12 and the anode electrode 2 15 are formed in the multilayer structure of the substrate 211, the backside wiring layer is formed on the backside of the substrate 211. Need not be formed.

In the multilayer structure of the substrate 211, in addition to the power source electrode drive circuit 220a and the anode electrode drive circuit 220b, a memory element for operating the display device 2, a control element, and a memory display Arbitrary elements such as a controller and a driver can be provided.

The functional material layer 2 13 can be made of various materials. The present invention can be applied to any type of display device by changing the material of the functional material layer 2 13. For example, when the present invention is applied to a liquid crystal display device, a liquid crystal layer may be used as the functional material layer 21. When the present invention is applied to an organic light emitting device, an organic electroluminescent light emitting layer may be used as the functional material layer 21. In this case, the functional material layer 213 includes an electron transport layer 213a and a hole transport layer 213b. The present invention is suitable for inorganic light emitting devices. When used, an inorganic electorescence luminescent layer may be used as the functional material layer 21.

When the display device 2 is a liquid crystal display device, further configurations such as a deflection filter and a color filter are required, but these configurations are omitted in FIGS. 7 and 8.

FIG. 11 shows an example in which an active matrix element is formed on the back surface of a substrate 211. An active matrix element (for example, a MOS transistor) is formed by forming a thin film gate layer of amorphous silicon or polysilicon on a substrate 211 using a method such as CVD or sputtering. It is formed.

High-temperature processes are required when forming active matrix devices. Therefore, the material of the substrate 211 is preferably a ceramic or a metal having a heat resistance of 300 degrees or more.

In order to perform active matrix driving, it is necessary to store signals to be supplied to a pixel during a period corresponding to one cycle of a scanning line, and to continuously send a current corresponding to the time signal corresponding to the one cycle to the pixel. . To do so, a memory element having a memory function (that is, a function of storing a signal and supplying a current corresponding to the amount of memory to the pixel) and a backflow prevention function (that is, power is supplied only to a specific pixel) And a control element having a switching function for preventing power from being supplied to other pixels.

The memory element and the control element having such a function can be formed directly on the substrate 211 using a known process.

In FIG. 11, reference numeral 231 denotes a current gate circuit element, and reference numeral 232 denotes a current control circuit element. 2 3 3 indicates a capacitor for determining the time constant. Further, a power line 234 for supplying power and a ground line 235 (earth) are provided. Note that reference numeral 236 denotes a drain, 237 denotes a gate, 238 denotes a source, 239 denotes a signal line, and 240 denotes a scanning line. FIG. 12 shows a circuit configuration of the circuit element shown in FIG.

As described above, by providing a memory element, a control element, a memory display controller, a driver, and the like for operating the display device 2 on the surface opposite to the light emitting surface of the display device 2 (that is, the back surface of the substrate), wiring can be achieved. By reducing the length of the wiring, it is possible to reduce the resistance of the wiring, and further, as described above, on the back surface of the substrate. Providing wiring and elements is very effective in realizing a large-area or high-definition screen.

According to the present invention, a plurality of pixel regions are driven simultaneously. As a result, a large-area or high-definition screen can be realized using a display device having a simple matrix structure.

In the present invention, since a simple matrix structure is used, there is an advantage that a process required for manufacturing a display device is shorter than an active matrix structure, and a high-temperature process is not required in the manufacturing process. As a result, costs can be reduced.

Further, according to the present invention, it is not necessary to suppress the resistance value of the transparent electrode. Thereby, the material of the transparent electrode can be freely selected. Further, the thickness of the transparent electrode can be reduced. This reduces costs and increases reliability. Thus, the present invention makes it possible to provide a display device that realizes a large-area or high-definition screen at low cost. Further, the present invention is a common basic technology applicable to various displays. Therefore, the combined effect of the present invention is large.

Further, in the present invention, since a plurality of pixel regions are driven at the same time, the area of the screen to be scanned can be reduced. As a result, the response speed of the display device is improved. Up. Further, since the area of the screen to be scanned is reduced, the voltage applied to the scanning electrodes and the signal electrodes can be reduced. This makes it possible to suppress the occurrence of crosstalk. As a result, the quality of the display device is improved. In addition, a reduction in the voltage applied to the scanning electrode and the signal electrode can reduce power consumption, improve reliability, and reduce the cost of the driving circuit.

Further, according to the present invention, a drive circuit for driving the force source electrode and a drive circuit for driving the anode electrode are provided in the multilayer structure of the substrate. Alternatively, a voltage applied to the force source electrode and a voltage applied to the anode electrode are supplied from the back surface of the substrate. As a result, it is not necessary to arrange an extraction electrode for extracting those voltages on the side surface of the display device. This makes it possible to tiling display devices in two dimensions. As a result, a large-screen or high-definition screen can be realized using a display device having a simple matrix structure.

In addition, by supplying those voltages from the back surface of the substrate, the aperture ratio can be increased, the work of wiring and the work of manufacturing the light emitting element can be separated, and the active matrix element can be directly placed on the substrate. The advantage is that multilayer wiring can be realized by making the substrate a multilayer structure.

Further, by using a ceramic or metal other than glass as the substrate material, the heat radiation characteristics can be improved.

Claims

The scope of the claims

1. A first substrate, including a second substrate facing the first substrate, and a functional material layer provided between the first substrate and the second substrate,

A plurality of signal electrodes driven by a common signal voltage are formed on the first substrate;

A display device, wherein a scanning electrode is formed on the second substrate so as to face the plurality of signal electrodes.

2. The display device according to claim 1, wherein the first substrate is a transparent substrate, and the signal electrode is a transparent electrode.

3. The display device according to claim 1, wherein the second substrate is a transparent substrate, and the scanning electrode is a transparent electrode.

4. A first substrate, including a second substrate facing the first substrate, and a functional material layer provided between the first substrate and the second substrate,

A plurality of signal electrode groups are formed on the first substrate, each of the plurality of signal electrode groups includes a plurality of signal electrodes arranged in a predetermined first direction,

A plurality of scan electrode groups are formed on the second substrate so as to face the plurality of signal electrode groups, each of the plurality of scan electrode groups includes a plurality of scan electrodes extending in a predetermined second direction;

A scan voltage is applied to a plurality of scan electrodes selected from the plurality of scan electrode groups, and a signal voltage is applied to the plurality of signal electrodes included in one of the plurality of signal electrode groups. Display device.

5. The display device according to claim 4, wherein the first substrate is a transparent substrate, and the signal electrode is a transparent electrode.

6. The display device according to claim 4, wherein the second substrate is a transparent substrate, and the scanning electrode is a transparent electrode.

7. The display device further includes a plurality of signal lines formed on the first substrate, and one of the plurality of signal lines is included in one of the plurality of signal electrode groups. The method according to claim 4, wherein the signal electrodes are connected to the plurality of signal electrodes.

8. The display device according to claim 7, wherein the plurality of signal lines are provided between adjacent signal electrodes.

9. A pad is formed at a position on the first substrate corresponding to a gap between adjacent scan electrodes of the plurality of scan electrodes, and one of the plurality of signal lines is taken out through the pad. The display device according to claim 7, wherein:

10. The display device according to claim 1, wherein a sheet resistance of the signal electrode is from 100 ohm Z square centimeter to 10 ohm Z square centimeter.

11. The display device according to any one of claims 1 to 10, wherein the signal electrode is made of a simple material of tin oxide or zinc oxide or a mixed material thereof.

12. The display device according to any one of claims 7 to 11, wherein the signal line is made of a binary alloy material containing aluminum or copper.

13. A substrate having a multilayer structure;

A plurality of first electrodes formed on the substrate,

A functional material layer formed on the plurality of first electrodes,

A plurality of transparent second electrodes formed on the functional material layer;

With

Each of the first electrode and the second electrode is electrically connected to a wiring provided in the substrate having the multilayer structure.

1 4. a substrate having a first surface and a second surface facing the first surface;

A plurality of first electrodes formed on the first surface of the substrate,

A functional material layer formed on the plurality of first electrodes,

With

The display device, wherein both the voltage applied to the plurality of first electrodes and the voltage applied to the plurality of second electrodes are supplied from the second surface of the substrate.

15. The display device according to claim 14, wherein means for driving the plurality of first electrodes and the plurality of second electrodes is provided on the second surface of the substrate.

16. The display device according to claim 14, wherein the functional material layer is a liquid crystal layer.

17. The display device according to claim 14, wherein the functional material layer is an organic electroluminescent luminescent layer.

18. The display device according to claim 14, wherein the functional material layer is an inorganic electroluminescent layer.

19. The display device according to claim 14, wherein the substrate is made of a flexible material.

20. Before reaching the second electrode from the second surface of the substrate K

15. The display device of claim 14, wherein the thickness of the display device is between 50 microns and 150 microns.