KR20050051816A - Organic electro luminescence display device - Google Patents

Abstract

A plurality of data lines, a plurality of scan lines intersecting the data lines, an organic electroluminescent element disposed in an arbitrary shape in a pixel region formed by crossing the plurality of day lines and the scan lines, and the organic electroluminescent element are driven. The organic electroluminescent element includes an organic light emitting layer, an anode electrode and a cathode electrode disposed with the organic light emitting layer interposed therebetween, and is formed by bending a corner portion exposed into the pixel region.

Description

Organic electroluminescent display device {ORGANIC ELECTRO LUMINESCENCE DISPLAY DEVICE}

The present invention relates to an organic electroluminescent display, and more particularly, to a structure of an organic electroluminescent device.

An organic electroluminescent display is commonly referred to as EL for convenience. A display device is a self-luminous display that electrically excites fluorescent and / or phosphorescent organic compounds to emit light, and can be driven at a low voltage. It is a display that can easily solve the drawbacks pointed out as a problem in the liquid crystal display device, such as a wide viewing angle, fast response speed, has attracted attention as a next-generation display, in particular, a display for mobile.

In the organic EL display device, an organic light emitting layer having a predetermined pattern is formed on glass or other transparent insulating substrate, and anode and cathode electrode layers are formed on and under the organic light emitting layer to apply a driving voltage to the organic light emitting layer. The organic light emitting layer is formed of an organic compound.

In the organic EL display device having such a basic configuration, as the anode and cathode voltages are applied to the electrodes, holes injected from the electrode to which the anode voltage is applied are moved to the organic light emitting layer via the hole transport layer, and the electrons are The cathode is injected into the organic light emitting layer through the electron transport layer from the electrode. As a result, electrons and holes are recombined in the organic light emitting layer to generate excitons, and the organic material of the organic light emitting layer emits light as the excitons change from the excited state to the ground state, thereby realizing a desired image. Will be.

FIG. 7 illustrates a cross-sectional structure of a conventional active matrix type organic EL display device, and is a cross-sectional view, particularly with respect to a portion where a driving transistor is disposed.

Referring to the drawings, in the organic EL display device, a buffer layer 105 is formed on an insulating substrate 100, and a driving transistor and a capacitor are formed on the buffer layer 105. The driving transistor may be formed on the semiconductor layer 110 including the source / drain regions 111 and 115, the gate electrode 125 formed on the gate insulating layer 120, and the interlayer insulating layer 130. And the source / drain electrodes 141 and 145 connected through the / drain regions 111 and 115 and the contact holes 131 and 135.

In addition, the capacitor is formed of the same material as the gate electrode 125, and formed on the gate insulating layer 120, and the source / drain electrode 141 formed on the interlayer insulating layer 130. , 145, for example, a second electrode 147 connected to the source electrode 141.

An insulating layer 150 is formed on the substrate 100 over the driving transistor and the capacitor, and an anode electrode 160 electrically connected to the drain electrode 145 is formed on the insulating layer 150 on the pixel area. The anode electrode 160 may be made of indium tin oxide (ITO) and a transparent material, and the connection with the drain electrode 145 may expose the portion of the drain electrode 145 to expose the insulating layer 150. The anode electrode 160 is connected to the drain electrode 145 through a via hole 155 formed thereon.

An organic emission layer 180 is formed on the anode electrode 160, and a cathode electrode 190 made of a metal material such as aluminum (Al) is electrically connected to the organic emission layer 180, such an anode electrode 160. ), The organic light emitting layer 180 and the cathode electrode 190 constitute an organic EL element of the organic EL display device. In this case, a planarization film 170 is formed between the cathode electrode 190, the anode electrode 160, and the insulating layer 150.

On the other hand, in the conventional organic EL element, the organic light emitting layer 180 substantially constituting the organic EL display element has an angular shape as shown in FIG.

Accordingly, the rectangular corner portion of the cathode electrode 190 formed on the organic emission layer 180 also has an angled shape corresponding to the shape of the organic emission layer 180. Of course, the shape of the angled square corner portion of the organic light emitting layer 180 is due to the shape of the flattening film 170 which the organic light emitting layer 18 is in contact with.

The organic EL display element having such a shape has an advantage that the aperture ratio can be improved since the pixel area can be made as wide as possible to the area of the square corner portion of the component.

However, as described above, when the corner portion of each component is formed in an angular form, there is a high possibility that the corner portion may not be formed smoothly in an angular form during the manufacturing process, resulting in a decrease in yield due to poor manufacturing, Substantially, for example, when the organic EL display device operates while the corner portion of the organic light emitting layer 180 is poorly formed, an abnormality occurs in the organic light emitting layer 180, resulting in a shortening of the device life due to its deterioration. Caused.

Accordingly, the present invention has been made in view of the above problems, and an object of the present invention is to provide an organic EL display device which can prevent the life of the device from being shortened due to the shape of the organic EL element.

In the organic EL display device according to the present invention,

A plurality of data lines, a plurality of scan lines intersecting the data lines, an organic electroluminescent element disposed in an arbitrary shape in a pixel region formed by crossing the plurality of day lines and the scan lines, and the organic electroluminescent element are driven. The organic electroluminescent element includes an organic light emitting layer, an anode electrode and a cathode electrode disposed with the organic light emitting layer interposed therebetween, and is formed by bending a corner portion exposed into the pixel region.

The corner portion may be formed by one arc connecting two sides of the shape of the organic electroluminescent element, wherein the radius of curvature R forming the arc satisfies 3 to 15 μm.

The corner portion may be formed by at least two circular arcs connecting two sides having the shape of the organic electroluminescent element and one straight line disposed between and connected to the circular arcs.

In addition, the corner portion may be formed by a plurality of straight lines connecting two sides of the shape of the organic EL device.

In addition, the corner portion may be formed by one straight line connecting two sides of the shape of the organic EL device.

Hereinafter, an embodiment for clarifying the present invention will be described in detail with reference to the accompanying drawings.

1 is a diagram schematically showing an organic EL display device according to the present invention, and FIG. 2 is a diagram illustrating a configuration corresponding to one pixel in the organic EL display device according to the present embodiment. 3 is an enlarged partial cutaway perspective view of the marked portion A of FIG. 2.

As illustrated, the organic EL display device of the present invention includes an organic EL display panel 100, a data driver 200, and a scan driver 300.

The organic EL display panel 100 includes a plurality of data lines D1 ?? Dm extending in the column direction and a plurality of scan lines S1 intersecting the data lines D1 ?? Dm and extending in the row direction. The organic EL display element 40 and the organic EL display element 40 disposed in a pixel region formed by crossing the Sn and the data line D1 ?? Dm and the scan line S1 ?? Sn And a pixel driving element 50 for driving.

The organic EL display device 40 includes the organic light emitting layer 40a and an anode electrode 40b and a cathode electrode 40c disposed between the organic light emitting layer 40a and the pixel driving device. 50 includes at least two transistors 52 and 54, and a capacitor 56 electrically connected to the transistors. In the present embodiment, the transistors 52 and 54 are arranged according to the voltage applied to the gate. Two driving transistors 54 for controlling the current flowing to the organic EL display element 40, and two switching transistors 52 for transmitting the image signal applied to the data line to the driving transistor 52 in response to a selection signal. It is divided.

The switching transistor 52 is disposed close to the data line D1 ?? Dm and the scan line S1 ?? Sn, and the source electrode 52a is electrically connected to the data line D1 through the contact hole 60. The drain electrode 52b is electrically connected to the drain electrode 52b through the contact hole 62 and the gate electrode of the driving transistor 54 arranged at a position difference from the switching transistor 52.

In contrast, the driving transistor 54 electrically connects its drain region to the power supply line Vdd arranged in parallel with the data line D1 through the contact hole 64. The region is electrically connected to the anode electrode 40b of the organic EL display element 40 through the via hole 66.

In addition, the capacitor 56 may be formed by the power supply line Vdd and the gate electrode of the driving transistor 54.

On the other hand, in the present invention, as shown in Fig. 2, the organic EL display element 40 is formed to have an arbitrary shape. At this time, the organic EL display element (exposed in the pixel region) The corner portion 40d of 40 has a curved shape as shown.

In the present invention, forming the corner portion 40d of the organic EL display element 40 by bending the corner of the organic EL display element 40 during the manufacturing process of the organic EL display element 40 is thus performed. This is to allow the portion 40d to be formed in a good state without manufacturing defects.

In the present embodiment, the corner portion 40d is formed by one arc Rc connecting two sides E1 and E2 of the shape of the organic EL display element 40, as shown in FIG. Can be.

Substantially, the curved state of the corner portion 40d is such that, during the manufacturing process of the organic EL display device, the planarization film 70 formed around the organic EL display element 40 is first applied to the corner portion 40d. In the state where the corresponding portion is formed in the curved state, the organic light emitting layer 40a and the cathode electrode 40c of the organic EL display element 40 are formed by matching the corner portion with the corner portion of the flattening film 70. You lose. The arc Rc which forms the corner part 40d in the above has the curvature radius R of 3-15 micrometers.

Thus, when the organic EL display element 40 is formed by bending the corner portion as described above, the shape of the corner portion portion is smoothed during the manufacturing process, and when it is acting, malfunction can be prevented due to poor shape.

On the other hand, in the present invention, the corner portion 40d is not necessarily formed by one arc as described above.

That is, as shown in Figs. 4 to 6, the corner portion 40d may be formed by a combination of at least two or more arcs R1 and R2 and one straight line L1 disposed between the arcs. (See Fig. 4), a plurality of straight lines (L2, L3, L4) may be formed at any angle therebetween (see Fig. 5), can also be formed by one straight line (L5) (Fig. 6).

Although the preferred embodiments of the present invention have been described above, the present invention is not limited thereto, and various modifications and changes can be made within the scope of the claims and the detailed description of the invention and the accompanying drawings. Naturally, it belongs to the scope of the invention.

As described above, the organic EL display device according to the present invention improves the shape of the organic EL display element, in particular, the shape of the corner portion thereof, so that the manufacturing state thereof can be satisfactorily achieved, so that the life can be extended with smooth operation. do.

1 is a schematic diagram illustrating an organic light emitting display device according to an exemplary embodiment of the present invention.

FIG. 2 is a partial plan view illustrating a configuration corresponding to one pixel in the organic light emitting display according to the exemplary embodiment of the present invention.

3 is an enlarged partial cutaway perspective view of portion A of FIG. 2.

4 to 6 are partial plan views schematically illustrating corner portions of an organic light emitting diode display according to another exemplary embodiment of the present invention.

FIG. 7 is a partial cross-sectional view illustrating a configuration corresponding to one pixel in a general organic light emitting display device.

FIG. 8 is a plan view illustrating a configuration corresponding to one pixel in a typical organic electroluminescent display.

Claims (6)

A plurality of data lines, a plurality of scan lines intersecting the data lines, an organic electroluminescent element disposed in an arbitrary shape in a pixel region formed by crossing the plurality of day lines and the scan lines, and the organic electroluminescent element are driven. An organic electroluminescent display comprising a pixel driving element for The organic electroluminescent device includes an organic light emitting layer, an anode electrode and a cathode electrode disposed between the organic light emitting layer, And a corner portion exposed to the pixel area. The method of claim 1, And the corner portion is formed by one arc connecting two sides of the shape of the organic light emitting element. The method of claim 2, An organic electroluminescence display device, wherein the radius of curvature R forming the arc is 3 to 15 µm. The method of claim 1, And the corner portion is formed by at least two circular arcs connecting two sides having the shape of the organic electroluminescent element and one straight line disposed between and connected to the circular arcs. The method of claim 1, And the corner portion is formed by a plurality of straight lines connecting two sides of the shape of the organic electroluminescent element. The method of claim 1, And the corner portion is formed by one straight line connecting two sides of the shape of the organic electroluminescent element.