JPH10154583A - Organic electroluminescence display device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To realize a high defination image screen, and realize a large image screen by the same technology by dividing the whole display device into a large number of electroluminescent area blocks, and driving them by constituting the inside of respective block areas of a larger number of light emitting elements. SOLUTION: An organic electroluminescence display device is formed by juxtaposing organic electroluminescent elements in a plurality, and ITO electrodes 21 are arranged on a lattice on a substrate, and an organic material is deposited over the whole surface on it, and metallic electrodes 22 are also arranged so as to become perpendicular to the ITO electrodes 21. A plus pole is applied on a single ITO electrode 21 to emit the light, and when the minus side is applied on the metallic electrodes 22, the light is emitted in a crossing part of the ITO electrodes 21 and the metallic electrodes 22. Connection of respective scanning electrodes is switched to emit the light over the whole surface. The scanning line side is normally connected to a minus, and signal currents are simultaneously flowed to the signal conductor side, and the light is emitted at once over the whole conductors.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an organic light-emitting display device using an organic material.

[0002]

2. Description of the Related Art Research on a light emitting device using an organic material has already been announced for more than 20 years. The possibility of practical application became apparent after Kodak's research announcement in 1987, and at this time the basic characteristics are similar to those announced at that time. Its features are high brightness,
Light-emitting devices that are light, thin, have a high response speed, and have high efficiency are not found in conventional light-emitting devices.

[0003] Organic light-emitting devices have many characteristics due to the variety of constituent materials. However, since many colors have been proposed even now, particularly with respect to luminescent colors, full-color realization is not expected to be realized. It is. In the situation where reliability concerns, which have been an issue at last, are finally being removed, if reliability is established, its application will be expanded rapidly.

[0004]

Although it has been found that organic light emitting devices are devices that have a number of advantages, they do not meet all of the issues required of conventional devices. One of them is the problem of high definition or large area, which is an indispensable factor when considering application to displays.

The reason why it is difficult to achieve high definition is that an organic light emitting device is a device that emits light by passing an electric current (the luminance and the electric current are completely proportional to each other in a range of 5 digits). A current must be supplied to each of the light emitting regions. On the other hand, emitting light by passing current has the advantage of not emitting light where current does not flow (a display with a high signal / noise ratio can be obtained because there is no need to worry about induction, etc.). A voltage drop determined by the product of the electric resistance and the current occurs, causing a decrease in efficiency, and
A drawback is that it leads to an increase in drive voltage. As a solution for this, a device such as driving with a constant current circuit is devised. However, the higher the definition is, the thinner the lead wire becomes, and most of the power is consumed in the lead wire portion.

Another problem is that in order to compose a moving picture plane, it is general to divide the whole screen into small parts and operate each part by simple matrix driving. To this end, the screen is driven line-sequentially. In order to obtain a definition screen, the number of scanning lines increases. Since the number of light emission lines is always one, the light emission luminance at the time of light emission must be high by the increase in the number of lines. If you describe the device level of the current technology,
When the average luminance is 100 cd / m ² and the number of scanning lines is 100, the emission luminance is 100 × 100 =
10,000 cd / m ² is required. Although the maximum luminance at the instantaneous value of the organic light emitting element is reported to be 100,000 cd / m ² or more, the maximum luminance of the instantaneous value is tens of thousands cd / m ² when the element deterioration is considered. It is difficult to increase the average brightness and increase it.

[0007] The electrical resistance of the lead portion, which is another problem of high definition, lowers the electrical resistance of the ITO transparent electrode. However, the current sheet resistance of 10 ohm / cm2 can be reduced by orders of magnitude. After all it is difficult.

In the current materials and device configurations, the upper limit is about 200 scanning lines and the screen size is about 10 cm.

[0009]

SUMMARY OF THE INVENTION The present invention relates to a display device which emits light by passing a current through an organic material. The entire display device is divided into a large number of light-emitting region blocks, and each block region has a larger number of light-emitting regions. It is characterized by being constituted by a light emitting element and driven.

[0010]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention aims at high definition and large size of an organic light emitting device. The basic idea is to divide the luminescent screen into divided blocks in a certain area, configure the luminescent screen in the divided blocks, and control the entire screen by controlling each divided block.

In order to control each of the divided blocks independently, an independent circuit is required in each block. The biggest problem at that time is how to perform wiring for transmitting signals to each block. Come on.

An organic light-emitting device has a transparent electrode 1 on a substrate material.
500 Å, the hole transport layer 500 Å, the light emitting layer 500 Å, and the cathode electrode 1500 Å have a total thickness of 0.5 μm or less on the substrate. This feature, thinness,
The ability to freely use the rear surface of the electrode is a feature not found in other devices, and the present invention takes advantage of this feature by
Wiring can be independently performed on each block.

[0013] Organic light-emitting devices are used in semiconductor silicon devices because they have a low heat resistance, so that it is not possible to introduce a process in which a temperature rise occurs after the device is manufactured, and because the materials constituting the device are soluble in an organic solvent. The process and associated materials cannot be used in organic light emitting devices.

By dividing the light emitting region in the organic light emitting device, it is possible to realize a display device having a high definition or a large area.

FIG. 2 shows a structural view of the organic light emitting device. Indium tin oxide, so-called ITO, on a glass substrate 11
An electrode 12 is provided, and a hole transporting material 13 and an electron transporting material 14 made of an organic material are provided thereon by a vapor deposition method, an immersion method, or a spin coating method.
Is provided. The electrode is most easily prepared by vapor deposition or sputtering. In the present invention, the electrode was prepared by vapor deposition.

Here, if the thickness of each layer is described, the glass serving as the substrate is set to 0.7 mm in consideration of ensuring structural strength and workability in manufacturing. An ITO electrode formed on a glass substrate by a sputtering method has a thickness of 0.15 μm. The hole transporting material and the electron transporting material each have a thickness of 500 angstroms. In addition, the cathode electrode is 1500 angstroms thick,
The thickness of the functional portion of the light emitting device of FIG. 2 is 0.5 μm or less as a whole.

FIG. 1 shows a configuration diagram of an organic light emitting display device according to an embodiment of the present invention. In FIG. 1, a plurality of light-emitting portions of FIG. 2 are arranged, and an ITO electrode 21 is arranged on a lattice on a substrate, an organic material is vapor-deposited thereon, and a metal electrode 22 is perpendicular to the ITO electrode. It is arranged so that it becomes. A positive electrode is applied to one ITO electrode to emit light, and light is emitted at the intersection of the ITO electrode and the metal electrode when a negative electrode is applied to the metal electrode. The connection of each scanning electrode is switched to emit light over the entire surface. Normally, the scanning line side is connected to the minus side, and a signal current is simultaneously applied to the signal line side to cause the entire line to emit light at a time. Further, one screen is constituted by switching the scanning lines and making a single round.

FIG. 3 shows an example of a configuration in which a driving circuit including a memory for controlling the light emitting block is mounted on the back of the light emitting block shown in FIG.

In FIG. 3, reference numeral 31 denotes an insulating layer provided on the electrode, and reference numeral 32 denotes a block control circuit and a memory. The electrodes that energize the light-emitting block are a plurality of scanning electrodes and a plurality of signal electrodes. As an example, when the number of pixels in a block is taken as 64 × 64, the number of scanning electrodes is 64 and the number of outlets is 64. When 64 signal lines are taken, the number of outlets is also 64 and the number of take-out portions is 128.

FIG. 4 shows an embodiment in which a hole from which the organic layer is removed is formed on the light emitting element at a portion corresponding to the extraction electrode portion, and a current-carrying electrode is provided in the hole. FIG. 4 shows a structure for taking out the ITO electrode on the light emitting element. The organic material on the ITO electrode 12 is removed to form a hole 41 (the organic material is provided on the entire surface of the light emitting element). A wiring member 43, which is a connecting wire base material, is provided above the hole, and the wiring member 43 is also provided with a hole. Hole 4
1 and the hole 42 are overlapped with each other to form a conductive paint 45 on the hole.
Is filled, the ITO electrode 12 is connected to the extraction electrode 44 which is a continuous conductive line. Since the scanning electrode is exposed on the surface of the light emitting element, it may be connected by a usual method.

Incidentally, a take-out electrode may be provided on the hole by a vapor deposition method. Further, an upper electrode may be connected to the hole using anisotropic conductive rubber.

FIG. 5 shows an example in which a groove is provided in the extraction electrode portion instead of the hole, and a connection line is fixed to the groove to connect the electrode. In FIG. 5, 50 is a groove, 51 is a connecting wire base material, 52
Is a connection line conductive material. The electrical connection between the connection line and the ITO electrode is based on mechanical stress, an adhesive such as a conductive paint, or the like.

FIG. 6 shows a configuration in which connection is made simply by a mechanical method. In this method, connection pins are set up from above and mechanically energized. In FIG. 6, reference numeral 61 denotes a connection pin, and 62 denotes a conductive material pad. If the mechanical connection between the ITO transparent electrode and the connection pin has a problem in reliability, it is also effective to provide a connection pad on the ITO transparent electrode. This pad is also effective as a bonding pad.

FIG. 7 shows an example of a configuration in which the electric wire is taken out from the side surface of the light-emitting block. In FIG. 7, reference numeral 71 denotes a connection line base material, and 72 denotes a connection line conductive material.

FIG. 8 shows a method of extracting a connection line from a side surface or a back surface by bending an extraction electrode portion of a light emitting element substrate using a flexible material.

In the above configuration example of the extraction electrode, the common feature is that the scanning electrode is used as a metal electrode (negative electrode), while the ITO electrode is used as a positive electrode. The reason is that a current corresponding to one light emitting element flows through the signal electrode, but a current corresponding to a plurality of light emitting elements collects and flows through the scanning electrode, so that the voltage drop is reduced and the reactive power is reduced. Therefore, it is more effective to use a metal electrode having a low electric resistance as the scanning electrode.

[0027]

As described above, according to the present invention, it is possible to realize a high-definition screen by blocking the light emitting section, and it is possible to enlarge the screen by the same technique.
The reason why the application range of the organic light emitting device can be expanded is that the thin organic light emitting element has led to the expansion of the application range.

[Brief description of the drawings]

FIG. 1 is a configuration diagram of an organic light emitting display device according to an embodiment of the present invention.

FIG. 2 is a structural view of an organic light-emitting element according to the present embodiment.

FIG. 3 is a configuration diagram of a driving circuit of the organic light emitting device according to the present embodiment.

FIG. 4 is a diagram showing a configuration of an extraction electrode unit in the present embodiment.

FIG. 5 is a diagram showing an example in which a connection line is fixed to a groove and an electrode is connected in the present embodiment.

FIG. 6 is a diagram illustrating a configuration in which connection is performed by a simple mechanical method in the present embodiment;

FIG. 7 is a diagram showing a configuration example of taking out from a side surface of a light-emitting block in the present embodiment.

FIG. 8 is a diagram showing a method for extracting a connection line from a side surface or a back surface in the present embodiment.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 11 Glass substrate 12 ITO transparent electrode 13 Hole transport material 14 Electron transport material 15 Cathode electrode 21 ITO transparent electrode 22 Cathode metal electrode 31 Interlayer insulating material 32 Block part control circuit and memory part 41 Organic material removal hole 42 Connection line hole 43 Wiring Member 44 extraction electrode 45 conductive filler 51 connecting wire base material 52 connecting wire conductive material 61 connecting pin 62 conductive material pad 71 connecting wire base material 72 connecting wire conductive material

Claims (13)

[Claims] 1. A display device which emits light by passing a current through an organic material, wherein the entire display device is divided into a large number of light emitting region blocks, and each block region is constituted by a further large number of light emitting elements. Organic light emitting display device. 2. The display of the entire device is performed by controlling light emission in each block unit, and a light emitting element in each block emits light based on a command from a device body or a driving unit including a memory in each block. The organic light emitting display device according to claim 1, wherein the organic light emitting display device emits light based on the instruction of (1). 3. Each block has two sets of current-carrying parts, one set of which is used as a scanning current-carrying part, and the other set is used as an electrode part for carrying a signal to supply a current. The organic light-emitting display device according to claim 1, having a function of supplying electricity. 4. As a method of energizing each block, the entire light emitting element electrode portion is covered with an insulator, a hole is formed in a portion to be a gap between the light emitting elements, and an electrode is taken out from the hole portion and energized. The organic light emitting display device according to claim 1, wherein: 5. The organic light emitting display device according to claim 1, wherein, as a method of energizing each of the blocks, a stylus is provided at a portion to be a gap between each light emitting region, and energization is performed from the stitch portion. 6. A method for energizing each block, wherein a groove is provided in a joint portion of each light emitting block region, an extraction electrode is provided in the groove, and each light emitting element is connected to the extraction electrode. 2. The organic light-emitting display device according to claim 1, wherein the current is supplied from a time. 7. The organic light-emitting display device according to claim 1, wherein, as a method of energizing each block, an extraction electrode is provided on a side surface of a substrate of each block, and energization is performed from the extraction electrode. 8. A method for energizing each block is to extend an electrode portion (scanning electrode and signal energizing electrode) on a side surface of the substrate of each block, to fold the extension, and to energize from the folded extraction electrode. 2. The method according to claim 1, wherein
The organic light-emitting display device according to the above. 9. A light-emitting element is formed on a transparent and flexible substrate, and a portion serving as an extraction electrode is provided for each block.
2. The organic light-emitting display device according to claim 1, wherein a take-out electrode is provided at the folded portion. 10. The method according to claim 1, wherein connection pads are provided for taking out electrodes on a part of the scanning line electrode and a part of the electrode on the signal line, and a current is supplied from the pad part. Organic light emitting display device. 11. The organic light emitting display device according to claim 4, wherein an extraction electrode is provided on the hole by a vapor deposition method. 12. The organic light emitting display device according to claim 4, wherein an upper electrode is connected to the hole using an anisotropic conductive rubber. 13. A scanning electrode is provided on a metal electrode side, and a signal line is provided on an ITO electrode side.
The organic light-emitting display device according to any one of the above.