TWI660500B - Organic light-emitting diode display device - Google Patents

Abstract

An organic light emitting diode display device includes a substrate, a lower electrode, a first organic layer, a light emitting layer, a second organic layer, an upper electrode, and an optical barrier layer. The lower electrode is disposed on the substrate. The first organic layer is disposed on the lower electrode. The light emitting layer is disposed on the first organic layer. The second organic layer is disposed on the light emitting layer. The upper electrode is disposed on the second organic layer, and the material of the upper electrode is a transparent conductive material or a translucent conductive material. The optical barrier layer is disposed on one side of the light emitting layer opposite to the second organic layer.

Description

Organic light emitting diode display device

The invention relates to an organic light emitting diode display device.

Organic Light Emitting Diode (OLED) is a light-emitting element using a light-emitting organic compound. It has self-luminous properties, and its thickness, display quality, and power-saving characteristics are better than those of a liquid crystal display (Liquid Crystal Display, LCD). Due to the wide viewing angle, high response speed, and ultra-thin characteristics of organic light emitting diodes, the application range of organic light emitting diode panels is becoming wider and wider.

Because the organic light emitting diode display device is self-luminous, it will have display characteristics with high contrast and high color saturation under the conditions of indoor or low ambient light. However, if the user is under a high-illumination ambient light source, the organic light-emitting diode itself will have lower brightness than the external ambient light, and the upper and lower electrodes are made of metal and have high reflectance. The external light reflected by the display device will seriously affect the picture quality of the display device.

As shown in FIG. 1, the prior art organic light emitting diode display includes an upper substrate 30, a lower substrate 40, and a thin film transistor layer 50. And an organic light emitting diode light emitting structure 10. The thin film transistor layer 50 is disposed on the lower substrate 40, the organic light emitting diode light emitting structure 10 is disposed on the thin film transistor layer 50, and the upper substrate 30 is provided on the organic light emitting diode light emitting structure 10. In order to cope with the foregoing problems, an organic light emitting diode display usually includes an additional optical anti-reflection structure 20 above the organic light emitting diode light emitting structure 10, more specifically, it is provided on the upper surface of the upper substrate 30. There is an optical anti-reflection structure 20, wherein the optical anti-reflection structure 20 includes a linear polarizer 21 and a circular polarizer 23 (which will cause a phase difference of a quarter wavelength). Therefore, the external light LO first passes through the linear polarizer 21 and the circular polarizer 23, and is then reflected by the upper electrode 11 and the lower electrode 13 of the organic light emitting diode light emitting structure 10, and then passes through the circular polarizer 23, and finally the external light LO It will be completely absorbed by the linear polarizer 21, so that the external light LO will not affect the picture quality of the display device. However, at the same time, after the internal light LI generated by the light-emitting layer 12 of the organic light-emitting diode light-emitting structure 10 is emitted, it will also pass through the optical anti-reflection structure 20 because the transmittance of the optical anti-reflection structure 20 is about 40%. Therefore, the luminous efficiency of the display device is greatly reduced. In addition, the additional provision of the optical anti-reflection structure 20 will also increase the thickness and weight of the overall device.

One technical aspect of the present invention is to provide an organic light emitting diode display device for improving its light-dark contrast.

According to an embodiment of the present invention, an organic light emitting diode display device includes a substrate, a lower electrode, a first organic layer, a light emitting layer, a second organic layer, an upper electrode, and an optical barrier layer. The lower electrode is disposed on the substrate. The first organic layer is disposed on the lower electrode. The light emitting layer is disposed on the first organic layer. The second organic layer is disposed on the light emitting layer. The upper electrode is disposed on the second organic layer, and the material of the upper electrode is a transparent conductive material or a translucent conductive material. The optical barrier layer is disposed on one side of the light emitting layer opposite to the second organic layer.

In one or more embodiments of the present invention, the material of the optical barrier layer is an organic conductive material.

In one or more embodiments of the present invention, the material of the optical barrier layer is graphite or graphene.

In one or more embodiments of the present invention, the material of the upper electrode is indium tin oxide (ITO), indium zinc oxide (IZO), zinc aluminum oxide (AZO), indium aluminum oxide (AIO), or indium oxide (InO). , Gallium Oxide (GaO), Nano carbon tubes, Nano silver wires, Nano silver particles or composite transparent conductive materials.

In one or more embodiments of the present invention, the optical barrier layer is disposed between the lower electrode and the first organic layer.

In one or more embodiments of the present invention, the optical barrier layer is disposed between the first organic layer and the light emitting layer.

In one or more embodiments of the present invention, the optical barrier layer has a function of transmitting electrons / holes or controlling electron / hole injection.

In one or more embodiments of the present invention, the first organic layer and the second organic layer have a composite layer structure, respectively.

In one or more embodiments of the present invention, the material of the first organic layer and the material of the second organic layer are respectively an organic conductive material or an organic and inorganic mixed conductive material.

In one or more embodiments of the present invention, the lower electrode is a transparent conductive material or an opaque conductive material.

According to another embodiment of the present invention, an organic light emitting diode display device includes a substrate, a lower electrode, a first organic layer, a light emitting layer, a second organic layer, and an upper electrode. The lower electrode is disposed on the substrate, and the material of the lower electrode is an opaque conductive material. The first organic layer is disposed on the lower electrode. The light emitting layer is disposed on the first organic layer. The second organic layer is disposed on the light emitting layer. The upper electrode is disposed on the second organic layer, and the material of the upper electrode is a transparent conductive material or a translucent conductive material.

In one or more embodiments of the present invention, a material of the lower electrode is graphite, graphene, a carbon nanotube, or an organic metal co-evaporated material.

In one or more embodiments of the present invention, the material of the lower electrode is indium tin oxide (ITO), indium zinc oxide (IZO), zinc aluminum oxide (AZO), indium aluminum oxide (AIO), or indium oxide (InO). A composite material of Gallium Oxide (GaO), nano carbon tubes or nano silver particles with light absorbing materials such as graphite, graphene or black dye.

In one or more embodiments of the present invention, the material of the lower electrode is a composite material of a metal and a light absorbing material such as graphite, graphene, or a black dye.

In one or more embodiments of the present invention, the first organic layer and the second organic layer have a composite layer structure, respectively.

In one or more embodiments of the present invention, the material of the first organic layer and the material of the second organic layer are respectively an organic conductive material or an organic and inorganic mixed conductive material.

In the present invention, the upper electrode is made transparent or translucent, and a functional layer with light absorption is designed inside the structure of the organic light emitting diode display device to absorb external light generated from the external environment. Avoid the reflection of external light to affect the picture quality, and improve the light and dark contrast of the organic light emitting diode display device. In addition, since the present invention does not require any optical anti-reflection film layer or film externally mounted on the outside of the organic light emitting diode display device, it does not affect the self-luminous efficiency of the organic light emitting diode display device, and can further simplify product thickness and Reduce product weight and reduce design and production costs.

10‧‧‧Organic light emitting diode light emitting structure

11‧‧‧up electrode

12‧‧‧ luminescent layer

13‧‧‧ lower electrode

20‧‧‧Optical anti-reflection structure

21‧‧‧ linear polarizer

23‧‧‧ circular polarizer

30‧‧‧ Upper substrate

40‧‧‧ lower substrate

50‧‧‧ Active electrode array

100‧‧‧organic light emitting diode display device

110‧‧‧ lower substrate

111‧‧‧ thin film transistor layer

120‧‧‧ lower electrode

130‧‧‧first organic layer

140‧‧‧Light-emitting layer

150‧‧‧ second organic layer

160‧‧‧up electrode

170‧‧‧Optical barrier

180‧‧‧ Upper substrate

L1, LO‧‧‧External light

L2, L3‧‧‧‧ Light

LI‧‧‧Internal light

R, G, B ‧‧‧ sub pixels

FIG. 1 is a schematic cross-sectional view of an organic light emitting diode display device according to the prior art.

FIG. 2 is a schematic cross-sectional view of an organic light emitting diode display device according to an embodiment of the present invention.

FIG. 3 is a schematic top view of a single pixel according to an embodiment of the present invention.

Fig. 4 is a schematic cross-sectional view taken along the line AA 'in Fig. 3;

FIG. 5 is a schematic cross-sectional view of an organic light emitting diode display device according to another embodiment of the present invention.

FIG. 6 is a schematic cross-sectional view of an organic light emitting diode display device according to another embodiment of the present invention.

In the following, a plurality of embodiments of the present invention will be disclosed graphically. For the sake of clarity, many practical details will be described in the following description. It should be understood, however, that these practical details should not be used to limit the invention. That is, in some embodiments of the present invention, these practical details are unnecessary. In addition, in order to simplify the drawings, some conventional structures and components will be shown in the drawings in a simple and schematic manner.

FIG. 2 is a schematic cross-sectional view of an organic light emitting diode display device 100 according to an embodiment of the present invention. Various embodiments of the present invention provide an organic light emitting diode display device 100. Specifically, the organic light emitting diode display device 100 is a top-emitting organic light emitting diode display device.

As shown in FIG. 2, an organic light emitting diode display device 100 includes a lower substrate 110, a thin film transistor layer 111, a lower electrode 120, a first organic layer 130, a light emitting layer 140, a second organic layer 150, and an upper electrode. 160. The optical blocking layer 170 and the upper substrate 180. The thin film transistor layer 111 is disposed on the lower substrate 110, and the lower electrode 120 is provided on the thin film transistor layer 111. The first organic layer 130 is disposed on the lower electrode 120. The light emitting layer 140 is disposed on the first organic layer 130. The second organic layer 150 is disposed on the light emitting layer 140. The upper electrode 160 is disposed on the second organic layer 150 and is opposite to the lower electrode 120. The material of the upper electrode 160 is a transparent conductive material or a translucent conductive material. The optical blocking layer 170 is disposed on a side of the light emitting layer 140 opposite to the second organic layer 150. Specifically, the optical barrier layer 170 of this embodiment is disposed between the lower electrode 120 and the first organic layer 130.

Since the upper electrode 160 is transparent or translucent, the external light L1 generated from the external environment will pass through the upper substrate 180, the upper electrode 160, the second organic layer 150, the light emitting layer 140, and the first organic layer 130, and then be processed by The optical barrier layer 170 absorbs. In addition, part of the light generated from the light-emitting layer 140 will go downward and be absorbed by the optical blocking layer 170 (ie, the light L2), and another part of the light will travel upward and pass through the upper electrode 160, and then emit organic light from the upper substrate 180 Light-emitting diode display device 100 (ie, light L3). Therefore, the organic light emitting diode display device 100 can avoid the reflection of external light L1 and affect the picture quality, thereby improving the light-dark contrast of the organic light emitting diode display device 100.

In this regard, compared with other organic light emitting diode display devices, the organic light emitting diode display device 100 of this embodiment does not need to be provided with other additional devices (for example, FIG. 1 includes an upper substrate 30). The optical anti-reflection structure 20 of the linear polarizer 21 and the circular polarizer 23 above is used to avoid reflection of external light L1 and affect the picture quality. Therefore, the thickness of the organic light emitting diode display device 100 can be thinner and lighter.

In addition, since the optical barrier layer 170 is disposed on one side of the light-emitting layer 140 opposite to the second organic layer 150, the optical barrier layer 170 can also serve as a thin film disposed on the lower substrate 110 and between the lower substrate 110 and the lower electrode 120. The light-shielding layer of the transistor layer 111 prevents the thin-film transistor from generating defects related to photocurrent after the thin-film transistor layer 111 is illuminated. For a clearer explanation, please refer to FIG. 3 and FIG. 4 together, which are a schematic top view of a single pixel according to an embodiment of the present invention and a cross-sectional view along the AA ′ section line in the top view, in which the dot area Is the optical barrier layer 170, the dotted line The enclosed range is the sub-pixel range. As can be understood from FIG. 3 and FIG. 4, since the optical barrier layer 170 of this embodiment is an opaque layer designed as a complete plane, the thin film transistor layer 111 located below the optical barrier layer 170 is viewed from the above perspective. It can be completely blocked but not visible, while the light emitting layer 140 (for example, containing three sub-pixels R, G, B) located above the optical blocking layer 170 is visible and operates to present colors. The embodiment of the single pixel is to explain the function of the optical barrier layer 170 as a light-shielding layer of the thin film transistor layer 111. Therefore, only the stack between the light emitting layer 140, the optical barrier layer 170, and the thin film transistor layer 111 is illustrated. For the structural relationship, other functional layers of the organic light emitting diode display device (such as the electrode 120, the first organic layer 130, and the like) are omitted and not shown.

Further, the first organic layer 130, the second organic layer 150, and the optical barrier layer 170 have the ability to transmit or inject electrons or holes, and are used to transfer the electrons and holes in the lower electrode 120 and the upper electrode 160 to make the electrons and Electric holes are combined in the light emitting layer 140. In other words, in some embodiments, the first organic layer 130 and the second organic layer 150 may adopt a design of a composite layer structure, not limited to a structure having only one physical layer. For example, the first organic layer 130 may be designed, for example, as an organic layer including a multi-layer structure such as a hole injection layer and a hole transport layer; and the second organic layer 150 may be, for example, designed as a multilayer including an electron injection layer, an electron transport layer, or the like. Structure of the organic layer. In addition, the first organic layer 130 and the second organic layer 150 may be designed by selecting an organic conductive material or an organic and inorganic mixed conductive material for design, which is not limited herein.

Because the optical barrier layer 170 has the function of absorbing light and transmitting electrons / holes or controlling electron / hole injection, the light The scientific barrier layer 170 may replace an organic functional layer having a similar function in the first organic layer 130, such as an electron transport layer, an electron injection layer, a hole transport layer, or a hole injection layer, according to the light emitting diode display device 100. The design aspect is not limited here. Therefore, the process can be simplified.

Specifically, the material of the optical barrier layer 170 is a non-metallic material. More specifically, the material of the optical barrier layer 170 may be an organic conductive material or an inorganic conductive material. If the material of the optical barrier layer 170 is an organic conductive material, the material of the optical barrier layer 170 may be an organic small molecule material or an organic polymer material. If the material of the optical barrier layer 170 is an inorganic conductive material, the material of the optical barrier layer 170 may be graphite or graphene. It should be understood that the materials of the optical barrier layer 170 mentioned above are merely examples and are not intended to limit the present invention. Those with ordinary knowledge in the technical field to which the present invention pertains should elastically select the materials of the optical barrier layer 170 according to actual needs.

Specifically, the material of the lower substrate 110 may be glass or plastic. Plastics can include polyimide (PI), polypropylene (PP), polystyrene (PS), acrylonitrile-butadiene-styrene (ABS), polyethylene terephthalate (PET), polymer Vinyl chloride (PVC), polycarbonate (PC), polyethylene (PE), polymethyl methacrylate (PMMA), polytetrafluoroethylene (PTFE), etc. It should be understood that the materials of the lower substrate 110 mentioned above are merely examples and are not intended to limit the present invention. Those with ordinary knowledge in the technical field to which the present invention pertains should flexibly select the materials of the lower substrate 110 according to actual needs.

Specifically, the material of the upper electrode 160 and the lower electrode 120 may be indium tin oxide (ITO). However, it is not limited to this. In other embodiments, the material of the upper electrode 160 and the lower electrode 120 may be indium zinc oxide (IZO), oxide Aluminum zinc (AZO), aluminum indium (AIO), indium oxide (InO), gallium oxide (GaO), nano carbon tubes, nano silver wires, nano silver particles, or composite transparent conductive materials, such as Transparent conductive material mixed with conductive polymer and nano silver wire. In addition, the material of the lower electrode 120 may be metal, such as copper, and the lower electrode 120 of this embodiment may be designed with a transparent conductive material or an opaque conductive material.

FIG. 5 is a schematic cross-sectional view of an organic light emitting diode display device 100 according to another embodiment of the present invention. As shown in FIG. 5, the organic light emitting diode display device 100 according to the present embodiment is substantially the same as the organic light emitting diode display device 100 according to the foregoing second embodiment, and the main difference is that the organic light emitting diode 2 The optical barrier layer 170 of the polar display device 100 is disposed between the first organic layer 130 and the light emitting layer 140.

FIG. 6 is a schematic cross-sectional view of an organic light emitting diode display device 100 according to another embodiment of the present invention. As shown in FIG. 6, the organic light emitting diode display device 100 of this embodiment is substantially the same as the organic light emitting diode display device 100 of the foregoing embodiments of FIGS. 2 and 5. The main difference is that this embodiment The material of the lower electrode 120 of the organic light emitting diode display device 100 is, for example, designed using an opaque conductive material that can absorb light. In this way, the lower electrode 120 of this embodiment has the effect of absorbing light and can also serve as Optical barrier.

Specifically, the material of the lower electrode 120 may be graphite, graphene, carbon nanotubes, or an organic metal co-evaporated material (for example, 25% CuPC: 25% DCJTB: 50% Al). Alternatively, the material of the lower electrode 120 may be black conductive material such as graphite, graphene, and nano carbon tube, and magnesium silver alloy. Mixed structure of gold thin film. Alternatively, the material of the lower electrode 120 may be a transparent conductive material such as indium tin oxide, indium zinc oxide, zinc aluminum oxide, indium aluminum oxide, indium oxide, gallium oxide, nano carbon tube, or nano silver particles with graphite, graphene, Composite material of black dyed material or carbon light absorbing material. Alternatively, the material of the lower electrode 120 may be a metal combined with graphite, graphene, a black dyeing material, or a light absorbing material made of carbon.

As mentioned above, since the upper electrode 160 of this embodiment is transparent or translucent, the external light L1 generated from the external environment will pass through the upper substrate 180, the upper electrode 160, the second organic layer 150, the light emitting layer 140, and The first organic layer 130 is then absorbed by the lower electrode 120 that also has an optical barrier effect. In addition, part of the light generated from the light-emitting layer 140 will go downward and be absorbed by the lower electrode 120 (ie, light L2), which also has an optical blocking effect, and another part of the light will travel upward and pass through the upper electrode 160, and then The upper substrate 180 emits the organic light emitting diode display device 100 (ie, the light L3). Therefore, when the organic light emitting diode display device 100 of this embodiment is designed to have an optical blocking effect, the organic light emitting diode display device 100 can avoid the reflection of external light L1 and affect the picture quality, thereby improving the organic light emitting diode display. Light and dark contrast of the device 100.

In summary, the present invention designs a layer with a function of absorbing light inside the structure of the organic light emitting diode display device, so as to avoid the reflection of external light and affect the picture quality, thereby improving the light-dark contrast of the organic light emitting diode display device. In addition, since there is no need to design any optical anti-reflection film layer or film externally mounted on the organic light emitting diode display device, it will not affect the self-luminous efficiency of the organic light emitting diode display device, and is more important. What is needed is to simplify product thickness, reduce product weight, and reduce design and production costs.

Although the present invention has been disclosed in the above embodiments, it is not intended to limit the present invention. Any person skilled in the art can make various modifications and retouches without departing from the spirit and scope of the present invention. Therefore, the protection of the present invention The scope shall be determined by the scope of the attached patent application.

Claims (10)

An organic light emitting diode display device includes: a substrate; a lower electrode disposed on the substrate; a thin film transistor layer disposed on the substrate and located between the substrate and the lower electrode; a first organic Layer is disposed on the lower electrode; a light-emitting layer is disposed on the first organic layer; a second organic layer is disposed on the light-emitting layer; an upper electrode is disposed on the second organic layer, wherein the The material of the upper electrode is a transparent conductive material or a translucent conductive material; and an optical barrier layer is a complete flat opaque layer, which is disposed on one side of the light-emitting layer opposite to the second organic layer and correspondingly serves as the film. The light-shielding layer of the transistor layer completely shields the thin-film transistor layer. The organic light emitting diode display device according to claim 1, wherein the material of the optical barrier layer is an organic conductive material. The organic light emitting diode display device according to claim 1, wherein the material of the optical barrier layer is graphite or graphene. The organic light emitting diode display device according to claim 1, wherein the material of the upper electrode is indium tin oxide (ITO), indium zinc oxide (IZO), zinc aluminum oxide (AZO), indium aluminum oxide (AIO), Indium oxide (InO), gallium oxide (GaO), nano carbon tubes, nano silver wires, nano silver particles or composite transparent conductive materials. The organic light emitting diode display device according to claim 1, wherein the optical barrier layer is disposed between the lower electrode and the first organic layer. The organic light emitting diode display device according to claim 1, wherein the optical barrier layer is disposed between the first organic layer and the light emitting layer. The organic light emitting diode display device according to claim 1, wherein the optical barrier layer has a function of transmitting electrons / holes or controlling electron / hole injection. The organic light emitting diode display device according to claim 1, wherein the first organic layer and the second organic layer have a composite layer structure, respectively. The organic light emitting diode display device according to claim 1, wherein the material of the first organic layer and the material of the second organic layer are respectively an organic conductive material or an organic and inorganic mixed conductive material. The organic light emitting diode display device according to claim 1, wherein the lower electrode is a transparent conductive material or an opaque conductive material.