CN100395893C - Organic electroluminescent display - Google Patents

Abstract

An integrated organic electroluminescent display comprises a transparent display panel, a reflector plate and an adjustable light transmission brightness membrane, wherein the adjustable light transmission brightness membrane is arranged between the transparent display panel and the reflector plate.

Description

Organic Electroluminescent Displays

technical field

The present invention relates to an organic electroluminescent display technology, in particular to an integrated organic electroluminescent display, which combines a transparent display panel with a diaphragm that can adjust the brightness of light penetration, and when operating in different brightness environments Can still meet the needs of high contrast.

Background technique

In the flat display technology of the new century, organic electro-luminescent display (organic electro-luminescent display, hereinafter referred to as OLED) is a thin-film laminated display that uses organic compounds as light-emitting materials. Advantages such as low driving voltage. Generally speaking, the film laminated structure on the surface of the glass substrate of the OLED component includes an anode conductive layer, a hole injection layer, a hole transport layer, an organic electroluminescent film, an electron transport layer, an electron injection layer layer and a cathode metal layer. When an external electric field is applied to the OLED component, the electrons generated by the cathode metal layer and the holes generated by the anode conductive layer will relatively move into the organic electroluminescent film, and then the recombination of electrons and holes can be converted into luminescence. .

However, when the OLED component is operated in a high-brightness external environment, its internal reflective electrode layer will reflect the external ambient light, which reduces the contrast of the OLED component. There are two known ways to improve the contrast of OLED components, one of which is to use black light-absorbing material to make electrodes to avoid reflection; the other is to use a polarizer, which uses the principle of interference to adjust the incident light and Reflects light to exhibit destructive interference, thereby eliminating internal reflections. US Patent No. 6,211,613 proposes an OLED structure that can improve contrast and reduce power consumption. Please refer to FIG. 1 , which shows a schematic cross-sectional view of a conventional OLED. An OLED assembly 10 includes a transparent substrate 12, an anode layer 14, a light emitting layer 16, a cathode layer 18, an insulating layer 20 and a reflective layer 22, and one side of the transparent substrate 12 is provided with a circular polarizer )twenty four. The anode layer 14 is a transparent conductive material (for example: ITO), the cathode layer 18 is an aluminum metal layer, the insulating layer 20 is an aluminum oxide layer, and the reflection layer 22 is an aluminum metal layer. The arrow L _t indicates that an external light is incident on the inside of the OLED assembly 10, the arrow L _r indicates that the external light is reflected from the OLED assembly 10, but will be blocked by the circular polarizer 24, and the arrow L _e indicates the light emitted by the OLED assembly 10 , which can penetrate the circular polarizer 24 . Although the above method can reduce the internal reflection phenomenon caused by the external ambient light, it will reduce the luminous intensity of the OLED assembly 10 by 50%.

Contents of the invention

In view of this, the object of the present invention is to provide an integrated organic electroluminescent display, which is to match a transparent display panel with a diaphragm that can adjust the light penetration brightness, so that it can still meet the requirements when operating in different brightness environments. High contrast needs.

In order to achieve the above object, the present invention provides an integrated organic electroluminescence display, which includes a transparent display panel, a reflector, and an adjustable light transmission brightness diaphragm, and the adjustable light transmission brightness diaphragm is arranged on the Between the transparent display panel and the reflector, and a light sensor is used to detect the intensity of the external ambient light, wherein the intensity of the external ambient light detected by the optical sensor can be controlled by controlling the amount of electricity to adjust the light transmission mode of the adjustable light transmission brightness film, and wherein both the reflective sheet and the adjustable light transmission brightness film are located on the non-displaying side of the transparent display panel.

In order to make the above and other objects, features, and advantages of the present invention more comprehensible, a preferred embodiment will be described in detail below with reference to the accompanying drawings.

Description of drawings

FIG. 1 shows a schematic cross-sectional view of a known OLED.

FIG. 2 shows a schematic cross-sectional view of the organic electroluminescence display of the present invention.

Figure 3 shows how the grating film controls the amount of light transmitted when the external ambient light is bright.

Figure 4 shows how the grating film controls the amount of light transmitted when the external ambient light is dark.

Explanation of reference numbers

Known technology:

OLED component-10; transparent substrate-12; anode layer-14; light-emitting layer-16; cathode layer-18; insulating layer-20; reflective layer-22; circular polarizer-24.

The technology of the present invention:

Transparent display panel-30; transparent substrate-32; first transparent electrode layer-34; light-emitting layer-36; second transparent electrode layer-38; Apparatus - 44; Rays - 46, 48, 50, 52, 54.

Detailed ways

Please refer to FIG. 2 , which shows a schematic cross-sectional view of the organic electroluminescence display of the present invention. An integrated organic electroluminescence display, which includes a transparent display panel 30, an adjustable light transmission brightness film 40, a reflector 42 and a photo sensor (photo sensor) 44, and the adjustable light must be The transluminance film 40 is disposed between the transparent display panel 30 and the reflection sheet 42 . The transparent display panel 30 includes a transparent substrate 32 , a first transparent electrode layer 34 , a light emitting layer 36 and a second transparent electrode layer 38 . Preferably, the transparent substrate 32 is a glass substrate, the first transparent electrode layer 34 is an ITO layer, the light emitting layer 36 is an organic electroluminescent film, and the second transparent electrode layer 38 is an ITO layer. In addition, a hole injection layer, a hole transport layer, an electron transport layer, and an electron injection layer can also be formed between the first transparent electrode layer 34 and the second transparent electrode layer 38, which will not be described in detail here. stated.

The adjustable light penetration brightness film 40 is similar to a grating film (photo slit), which can detect the intensity of external ambient light through the light sensor 44, and then can control the external ambient light to enter the transparent display panel 30 and pass through. The amount of light transmitted through the grating diaphragm. Preferably, the adjustable light transmission brightness film 40 is an electrochromic (electrochromic) material or a liquid crystal material, which can control the amount of light transmission through the amount of electricity flowing through it. For example, an electrochromic material is an originally transparent material that can be turned into an opaque or colored substance by passing a weak current.

The feature of the present invention is that in order to make the contrast and brightness of the organic electroluminescent display reach the best condition when used in different brightness environments, the transparent display panel 30 is used as the main display panel, and the transparent display panel 30 and the reflection sheet 42 is provided with adjustable light penetrating brightness diaphragm 40 .

Please refer to Fig. 3, when the light sensor 44 detects that the external ambient light is bright, the light penetration of the grating film 40 can be controlled by the amount of electricity flowing through, and the grating film 40 can absorb part of the external light. ray 46, and part of the ray 48 is reflected, which can improve the contrast problem. Even, when the external ambient light is very bright, the grating film 40 can be adjusted to a light-tight mode, and the incident external light 46 will be completely blocked by the grating film 40, that is, only light is absorbed and not reflected, so that the The transparent display panel 30 produces a high contrast effect.

Please refer to FIG. 4 , when the light sensor 44 detects that the external ambient light is dark, the grating film 40 can be adjusted to the light transmission mode by passing the amount of electricity, and the grating film 40 only absorbs a small part of the external light. Light 50, and reflect most of light 52, which can improve the contrast problem. Even, as the ambient light gradually becomes darker, the grating film 40 can be gradually adjusted to a full light transmission mode, and a part of the self-luminous light 54 of the transparent display panel 30 itself can also be reflected by the reflection sheet 42 to enhance brightness. Therefore, even if the supply current of the OLED is lowered, the transparent display panel 30 can achieve the same brightness display effect.

It can be seen that the present invention utilizes the grating film 40 to control the internal reflection mode of the organic light-emitting display, so that the transparent display panel 30 can maintain the best contrast effect under different ambient light without additional use of polarizers or fabrication. Light-absorbing electrodes, so it can avoid the doubt of insufficient brightness of the panel. Moreover, as the light transmittance of the grating film 40 increases, the supply current of the organic light emitting display can also be reduced to obtain the advantages of power saving and high brightness.

Although the present invention has disclosed the preferred embodiment as above, it is not intended to limit the present invention, and those skilled in the art can make some changes and modifications without departing from the spirit and scope of the present invention, so the protection scope of the present invention should be The scope defined by the claims shall prevail.

Claims (6)

1. organic electro-luminescent display comprises:

One transparent display panel;

One reflector plate;

One adjustable lay the grain penetrates the brightness diaphragm, is arranged between this transparent display panel and this reflector plate; And

One optical inductor is the power that is used for detecting external environment condition light,

Wherein the power of the external environment condition light of detecting according to this optical inductor can be adjusted the light transmission mode that this adjustable lay the grain penetrates the brightness diaphragm by control electric weight size,

Wherein this reflector plate and this adjustable lay the grain penetrate the side that does not show that the brightness diaphragm all is positioned at this transparent display panel.

2. organic electro-luminescent display as claimed in claim 1, wherein this transparent display panel comprises:

One transparent substrates;

One first transparent electrode layer is formed on this transparent substrates;

One luminescent layer is formed on this first transparent electrode layer; And

One second transparent electrode layer is formed on this luminescent layer.

3. organic electro-luminescent display as claimed in claim 2, wherein this luminescent layer is an organic electric-excitation luminescent film.

4. organic electro-luminescent display as claimed in claim 1, wherein to penetrate the brightness diaphragm be a grating diaphragm to this adjustable lay the grain, the light amount of penetrating of may command external environment condition light.

5. organic electro-luminescent display as claimed in claim 4, wherein to penetrate the brightness diaphragm be an electrochromic material or a liquid crystal material to this adjustable lay the grain, it can control the light amount of penetrating by flowing through the electric weight size.

6. organic electro-luminescent display as claimed in claim 1, wherein this adjustable lay the grain penetrates the power that the brightness diaphragm is the external environment condition light that detects according to this optical inductor, is used for adjusting the light amount of penetrating of external environment condition light.

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