(19)
(11)EP 3 091 578 B1

(12)EUROPEAN PATENT SPECIFICATION

(45)Mention of the grant of the patent:
14.08.2019 Bulletin 2019/33

(21)Application number: 14877417.7

(22)Date of filing:  29.12.2014
(51)Int. Cl.: 
H01L 27/32  (2006.01)
G09G 3/32  (2016.01)
H01L 51/52  (2006.01)
(86)International application number:
PCT/CN2014/095335
(87)International publication number:
WO 2015/101258 (09.07.2015 Gazette  2015/27)

(54)

TRANSPARENT OLED DEVICE AND DISPLAY DEVICE EMPLOYING SAME

TRANSPARENTE OLED-VORRICHTUNG UND ANZEIGEVORRICHTUNG DAMIT

DISPOSITIF À DIODES ÉLECTROLUMINESCENTES ORGANIQUES TRANSPARENTES ET DISPOSITIF D'AFFICHAGE LE METTANT EN OEUVRE


(84)Designated Contracting States:
AL AT BE BG CH CY CZ DE DK EE ES FI FR GB GR HR HU IE IS IT LI LT LU LV MC MK MT NL NO PL PT RO RS SE SI SK SM TR

(30)Priority: 31.12.2013 CN 201310749017

(43)Date of publication of application:
09.11.2016 Bulletin 2016/45

(73)Proprietors:
  • Beijing Visionox Technology Co., Ltd.
    Beijing 100085 (CN)
  • Tsinghua University
    Beijing 100084 (CN)

(72)Inventors:
  • ZHANG, Guohui
    Beijing 100085 (CN)
  • LI, Mengzhen
    Beijing 100085 (CN)
  • LI, Man
    Beijing 100085 (CN)
  • DUAN, Lian
    Beijing 100085 (CN)

(74)Representative: Hanna Moore + Curley 
Garryard House 25/26 Earlsfort Terrace
Dublin 2, D02 PX51
Dublin 2, D02 PX51 (IE)


(56)References cited: : 
WO-A1-2013/190781
CN-A- 1 816 228
CN-A- 103 715 230
US-A1- 2003 201 716
US-A1- 2012 074 435
CN-A- 1 816 228
CN-A- 103 474 448
CN-A- 103 715 369
US-A1- 2006 097 251
  
      
    Note: Within nine months from the publication of the mention of the grant of the European patent, any person may give notice to the European Patent Office of opposition to the European patent granted. Notice of opposition shall be filed in a written reasoned statement. It shall not be deemed to have been filed until the opposition fee has been paid. (Art. 99(1) European Patent Convention).


    Description

    TECHNICAL FIELD



    [0001] The present invention relates to an organic light-emitting diode (OLED) device and in particular to a transparent OLED device and a display device using the transparent OLED device.

    BACKGROUND



    [0002] OLED devices are active light-emitting devices. Compared with thin-film transistor LCDs (TFT-LCDs) in the existing mainstream flat panel display technology, OLEDs, due to their advantages such as high contrast, wide angle of view, low power consumption, thinner size and the like, are expected to become the flat panel display technology of the next generation, and are one of technologies that are highly concerned among the existing flat panel display technologies.

    [0003] Due to the active light-emitting property of OLEDs, backlight is not required such that transparent display can be achieved. A transparent OLED display, with advantages of self-illumination and penetration of ambient light through the display screen, becomes a novel display technology in the future. However, in an existing transparent OLED device, both the anode and the cathode of the OLED device are prepared by using a transparent conductive layer. This results in the following defects:
    1. 1) inconsistent luminance of two light-emitting surfaces; and
    2. 2) incapable of individually adjusting the luminance of the two light-emitting surfaces.


    [0004] The state of the art is represented by the following publications:

    Chinese Patent publication No. CN 1 816 228 A (YOUDA PHOTOELECTRIC CO LTD [CN]);

    Chinese Patent publication No. CN 103 474 448 A (BOE TECHNOLOGY GROUP CO LTD);

    United States Patent publication No. US 2012/074435 A1 (HA JAE-HEUNG [KR] ET AL); and

    International Patent publication No. WO 2013/190781 A1 (TOSHIBA LIGHTING & TECHNOLOGY [JP]).


    Technical problems



    [0005] Technical problems to be solved by the present invention are to provide a transparent OLED device that can individually adjust light-emitting of two light-emitting surfaces and make the luminance of the two light-emitting surfaces consistent, and a display device that employs the transparent OLED device.

    Solution to the problems



    [0006] To solve the aforementioned problems, the present invention provides a transparent OLED device according to the claims including a plurality of pixels, each pixel including an organic functional layer, a first transparent electrode and a second transparent electrode being disposed on both sides of the organic functional layer respectively, a reflective electrode being disposed on one side of the organic functional layer, the area of the reflective electrode being less than that of the organic functional layer.

    [0007] Further, the reflective electrode is located between the first transparent electrode and the organic functional layer, and an insulating layer is disposed between the reflective electrode and the first transparent electrode.

    [0008] Further, the area of the reflective electrode is 10% to 50% of the area of the organic functional layer.

    [0009] Further, reflective electrodes between adjacent pixels in one direction are electrically connected, and the reflective electrodes are led out from pixels located at both ends and connected to a power supply.

    [0010] Further, the reflective electrode is located on the same side as the first transparent electrode, and is disposed in parallel to the first transparent electrode; and a slit is formed between the reflective electrode and the first transparent electrode. Further, insulating material is filled in the slit.

    [0011] Further, the second transparent electrode is divided into two portions, with one portion being disposed opposite to the reflective electrode and the other portion being disposed opposite to the first transparent electrode.

    [0012] Further, the first transparent electrode is an anode, and the second transparent electrode is a cathode; or the first transparent electrode is a cathode, and second transparent electrode is an anode.

    [0013] Further, the average light transmittance the first transparent electrode at a visible wavelength is 50% to 95%; and the average light transmittance of the second transparent electrode at a visible wavelength is 5% to 95%.

    [0014] The present invention also provides an organic light-emitting display device including the aforementioned transparent OLED device.

    [0015] The present invention achieves the following beneficial effects:

    [0016] With regard to the transparent OLED device, by providing a reflective electrode, a light-emitting device over a microdomain is combined with a transparent light-emitting device, such that the luminance on both sides of a transparent OLED device can be respectively adjusted to be the same or different as required. The present invention can be applied to the field of transparent illumination or display.

    SUMMARY



    [0017] The present teaching provides a transparent OLED device as detailed in claim 1. Also provided is an organic light emitting display device according to claim 7. Advantageous features are provided in dependent claims.

    BRIEF DESCRIPTION OF THE DRAWINGS



    [0018] 

    FIG. 1 is a schematic structural view of a transparent OLED device according to an embodiment not forming part of the present invention;

    FIG. 2 is a schematic planar structural view illustrating connection of a plurality of pixels according to the present invention; and

    FIG. 3 is a schematic structural view of a transparent OLED device according to the embodiment of the present invention.


    DETAILED DESCRIPTION



    [0019] In order to make those skilled in the art better understand and practice the present invention, the present invention will be further described hereinafter in detail with reference to the accompanying drawings and specific embodiments, but the embodiments exemplified hereinafter are not intended to limit the present invention.

    [0020] As shown in FIG. 1, in the embodiment not forming part of the present invention, a transparent OLED device includes a plurality of pixels. The size of each pixel is not limited. However, generally, the size of a pixel should be less than the minimum resolution of human eyes having a corresponding distance from the screen. Each pixel includes an organic functional layer 5. The organic functional layer 5, which is the same as an organic functional layer in the existing technique, includes a hole injection layer, an organic light-emitting layer, an electron injection layer and the like, and will not be described repeatedly here. A first transparent electrode 4 and a second transparent electrode 6 are disposed on both sides of the organic functional layer 5 respectively, wherein a substrate 1 is on the outer side of the first transparent electrode 4. A reflective electrode 2 is disposed on one side of the organic functional layer 5, and the area of the reflective electrode 2 is less than that of the organic functional layer 5. In this embodiment, the reflective electrode 2 is located between the first transparent electrode 4 and the organic functional layer 5, and an insulating layer 3 is disposed between the reflective electrode 2 and the first transparent electrode 4 in order to prevent a short circuit between the two.

    [0021] When the transparent OLED device of the present invention is in use, by powering on the reflective electrode 2 and the second transparent electrode 6, the transparent OLED device may be controlled to emit light towards the second transparent electrode 6; and by powering on the first transparent electrode 4 and the second transparent electrode 6, the double-sided light-emitting or display of the transparent OLED device may be achieved. In addition, if the reflective electrode 2, the first transparent electrode 4 and the second transparent electrode 6 are powered on simultaneously, but are subjected to a different current or voltage, it is possible to adjust the double-sided light-emitting luminance. In addition, by setting the color of an organic functional layer corresponding to the reflective electrode 2 in a different color from that of an organic functional layer corresponding to the first transparent electrode 4, the display color may be adjusted by the reflective electrode 2.

    [0022] In the present invention, the area of the reflective electrode is preferably 10% to 50% of the area of the organic functional layer. The effect of adjustment will not be significant when the area of the reflective electrode is too small, while the transparency of the OLED device will be influenced when the area of the reflective electrode is too large.

    [0023] Manufacture of the transparent OLED device of this embodiment includes the following steps:

    preparing a first transparent electrode 4 on a transparent substrate 1;

    preparing a reflective electrode layer on the first transparent electrode 4;

    etching a portion of the reflective electrode layer by processes such as coating, exposing, developing and etching, with the remaining portion forming a reflective electrode 2;

    etching an edge of the reflective electrode 2, such that a potion of the reflective electrode 2 connected to the first transparent electrode 4 is disconnected; filling the part where the reflective electrode 2 is disconnected from the first transparent electrode 4 with an insulating material to form an insulating layer 3;

    evaporating an organic functional layer 5 over the first transparent electrode 4 and the reflective electrode 2; and

    preparing a second transparent electrode 6 over the organic functional layer 5 to obtain a transparent OLED device of this embodiment.



    [0024] Nevertheless, what is described above is only a preferred scheme for manufacturing a transparent OLED device of this embodiment, and the actual manufacturing process is not limited thereto.

    [0025] In this embodiment, since the reflective electrode 2 is disposed between the first transparent electrode 4 and the second transparent electrode 6, to connect the reflective electrode 2 of each pixel to the power supply, the reflective electrodes 2 between adjacent pixels in one direction may be electrically connected, and the serially-connected reflective electrodes 2 are led out from pixels at both ends and connected to the power supply. As in the embodiment shown in Fig.2, in this embodiment, the reflective electrodes 2 between pixels of each row in the longitudinal direction, i.e., in a same row, are connected in series, and are led out from pixels at both extreme ends to form a reflective lead-out electrode 7, and the reflective lead-out electrode 7 is connected to an external power supply to supply power to the reflective electrode 2. Since the area of the first transparent electrode 4 in this embodiment completely covers the organic functional layer 5 of a pixel, the first transparent electrodes 4 between pixels in a same row may be connected in series and then led out from both ends to form a first transparent lead-out electrode 8 in the same manner as the reflective electrode; or, the first transparent electrodes 4 of all pixels may be electrically connected and then led out from the surrounding.

    [0026] As in the embodiment of the transparent OLED device of the present invention shown in Fig.3, in this embodiment, the reflective electrode 2 is located on a same side as the first transparent electrode 4, and is disposed in parallel to the first transparent electrode 4. To prevent a short circuit between the reflective electrode 2 and the first transparent electrode 4, a slit 9 may be formed between the reflective electrode 2 and the first transparent electrode 4. Further preferably, an insulating material may be filled in the slit 9 to enhance the insulating property. However, the second transparent electrode 6 in this embodiment is divided into two portions, with one portion being disposed opposite to the reflective electrode 2 and the other portion being disposed opposite to the first transparent electrode 4. To achieve the insulating effect, a slit is also formed between the two portions of the second transparent electrode 6. Furthermore, insulating material may be also filled in the slit.

    [0027] In the above-mentioned embodiments, the first transparent electrode 4 and the second transparent electrode 6 are a cathode and an anode of an OLED device respectively, and may be exchangeable in position. That is, the first transparent electrode 4 may be an anode and the second transparent electrode 6 may be a cathode; or, the first transparent electrode 4 may be a cathode and the second transparent electrode 6 may be an anode, without imposing any influence on the implementation of the present invention. The average light transmittance of the first transparent electrode 4 at a visible wavelength is 5% to 95%; and the average light transmittance of the second transparent electrode at a visible wavelength is 5% to 95%. When the average light transmittance of the second transparent electrode 6 at a visible wavelength is 5% to 50%, a large portion of light emitted by the OLED device is output from the side of the first transparent electrode 4, and a small portion thereof is output from the side of the second transparent electrode 6, thereby forming a double-sided display. Light emitted by the OLED device may be output from both sides, thereby forming a transparent OLED device.

    [0028] The protection scope of the present invention is defined by the appended claims.


    Claims

    1. A transparent organic light-emitting diode, OLED device, comprising a plurality of pixels, each pixel comprising an organic functional layer (5), a first transparent electrode (4) and a second transparent electrode (6) being disposed on both sides of the organic functional layer (5) respectively, a reflective electrode (2) is disposed on one side of the organic functional layer (5), and the area of the reflective electrode (2) is less than that of the organic functional layer (5), and the reflective electrode (2) is located on a same side as the first transparent electrode (4), and is disposed in parallel to the first transparent electrode (4); characterized in that: a first slit (9) is formed between the reflective electrode (2) and the first transparent electrode (4), the second transparent electrode (6) is divided into two portions, with one portion being opposite to the reflective electrode (2) and the other portion being opposite to the first transparent electrode (4), a second slit is formed between the two portions of the second transparent electrode (6), and both the first and second slits are filled with an insulating material (3).
     
    2. The transparent OLED device according to claim 1 characterized in that the area of the reflective electrode is 10% to 50% of the area of the organic functional layer.
     
    3. The transparent OLED device according to claim 1 or claim 2, characterized in that reflective electrodes between adjacent pixels in one direction are electrically connected, and the reflective electrodes are led out from pixels located at both ends and connected to a power supply.
     
    4. The transparent OLED device according to claim 1, characterized in that the first transparent electrode is an anode, and the second transparent electrode is a cathode; or the first transparent electrode is a cathode, and the second transparent electrode is an anode.
     
    5. The transparent OLED device according to claim 1, characterized in that an average light transmittance of the first transparent electrode at a visible wavelength is 50% to 95%; and the average light transmittance of the second transparent electrode at a visible wavelength is 5% to 95%.
     
    6. The transparent OLED device according to claim 1, characterized in that the area of the first transparent electrode completely covers the organic functional layer of a pixel.
     
    7. An organic light emitting display device comprising a transparent OLED device according to any one of claim 1 to claim 6.
     


    Ansprüche

    1. Transparente organische Leuchtdiodenvorrichtung, OLED-Vorrichtung, umfassend eine Vielzahl von Fotodioden, wobei jede Fotodiode eine organische funktionelle Schicht (5), eine erste transparente Elektrode (4) und eine zweite transparente Elektrode (6), die jeweils auf beiden Seiten der organischen funktionellen Schicht (5) angeordnet sind, umfasst, eine reflektierende Elektrode (2) auf einer Seite der organischen funktionellen Schicht (5) angeordnet ist und die Fläche der reflektierenden Elektrode (2) kleiner als die der organischen funktionellen Schicht (5) ist und die reflektierende Elektrode (2) sich auf derselben Seite wie die erste transparente Elektrode (4) befindet und parallel zu der ersten transparenten Elektrode (4) angeordnet ist; dadurch gekennzeichnet, dass: ein erster Schlitz (9) zwischen der reflektierenden Elektrode (2) und der ersten transparenten Elektrode (4) ausgebildet ist, die zweite transparente Elektrode (6) in zwei Abschnitte unterteilt ist, wobei ein Abschnitt entgegengesetzt zu der reflektierenden Elektrode (2) ist und der andere Abschnitt entgegengesetzt zu der ersten transparenten Elektrode (4) ist, ein zweiter Schlitz zwischen den zwei Abschnitten der zweiten transparenten Elektrode (6) ausgebildet ist und sowohl der erste als auch der zweite Schlitz mit einem Isoliermaterial (3) gefüllt sind.
     
    2. Transparente OLED-Vorrichtung nach Anspruch 1, dadurch gekennzeichnet, dass die Fläche der reflektierenden Elektrode 10 % bis 50 % der Fläche der organischen funktionellen Schicht beträgt.
     
    3. Transparente OLED-Vorrichtung nach Anspruch 1 oder 2, dadurch gekennzeichnet, dass reflektierende Elektroden zwischen benachbarten Fotodioden in einer Richtung elektrisch verbunden sind und die reflektierenden Elektroden aus Fotodioden heraus geleitet werden, die sich an beiden Enden einer Stromversorgung befinden und mit dieser verbunden sind.
     
    4. Transparente OLED-Vorrichtung nach Anspruch 1, dadurch gekennzeichnet, dass die erste transparente Elektrode eine Anode ist und die zweite transparente Elektrode eine Kathode ist; oder die erste transparente Elektrode eine Kathode ist und die zweite transparente Elektrode eine Anode ist.
     
    5. Transparente OLED-Vorrichtung nach Anspruch 1, dadurch gekennzeichnet, dass eine durchschnittliche Lichtdurchlässigkeit der ersten transparenten Elektrode bei einer sichtbaren Wellenlänge 50 % bis 95 % beträgt und die durchschnittliche Lichtdurchlässigkeit der zweiten transparenten Elektrode bei einer sichtbaren Wellenlänge 5 % bis 95 % beträgt.
     
    6. Transparente OLED-Vorrichtung nach Anspruch 1, dadurch gekennzeichnet, dass die Fläche der ersten transparenten Elektrode die organische funktionelle Schicht einer Fotodiode vollständig abdeckt.
     
    7. Organische Leuchtanzeigenvorrichtung, die eine transparente OLED-Vorrichtung nach einem der Ansprüche 1 bis 6 umfasst.
     


    Revendications

    1. Dispositif à diode électroluminescente organique, OLED, transparent, comprenant une pluralité de pixels, chaque pixel comprenant une couche fonctionnelle organique (5), une première électrode transparente (4) et une seconde électrode transparente (6) qui sont disposées respectivement sur les deux côtés de la couche fonctionnelle organique (5), une électrode réfléchissante (2) étant disposée sur un côté de la couche fonctionnelle organique (5), et la surface de l'électrode réfléchissante (2) étant inférieure à celle de la couche fonctionnelle organique (5), et l'électrode réfléchissante (2) étant située sur un même côté que la première électrode transparente (4), et étant disposée de manière parallèle à la première électrode transparente (4) ; caractérisé par le fait que :
    une première fente (9) est formée entre l'électrode réfléchissante (2) et la première électrode transparente (4), la seconde électrode transparente (6) est divisée en deux parties, avec une partie qui est opposée à l'électrode réfléchissante (2) et l'autre partie qui est opposée à la première électrode transparente (4), une seconde fente est formée entre les deux parties de la seconde électrode transparente (6), et à la fois la première et la seconde fente sont remplies avec un matériau isolant (3).
     
    2. Dispositif OLED transparent selon la revendication 1, caractérisé par le fait que la surface de l'électrode réfléchissante est 10 % à 50 % de la surface de la couche fonctionnelle organique.
     
    3. Dispositif OLED transparent selon la revendication 1 ou la revendication 2, caractérisé par le fait que des électrodes réfléchissantes entre des pixels adjacents dans une direction sont reliées électriquement, et les électrodes réfléchissantes sont sorties à partir de pixels situés aux deux extrémités et reliées à une alimentation électrique.
     
    4. Dispositif OLED transparent selon la revendication 1, caractérisé par le fait que la première électrode transparente est une anode, et la seconde électrode transparente est une cathode ; ou la première électrode transparente est une cathode, et la seconde électrode transparente est une anode.
     
    5. Dispositif OLED transparent selon la revendication 1, caractérisé par le fait qu'une transmittance de lumière moyenne de la première électrode transparente à une longueur d'onde visible est de 50 % à 95 % ; et la transmittance de lumière moyenne de la seconde électrode transparente à une longueur d'onde visible est de 5 % à 95 %.
     
    6. Dispositif OLED transparent selon la revendication 1, caractérisé par le fait que la surface de la première électrode transparente recouvre complètement la couche fonctionnelle organique d'un pixel.
     
    7. Dispositif d'affichage à émission de lumière organique comprenant un dispositif OLED transparent selon l'une quelconque de la revendication 1 à la revendication 6.
     




    Drawing









    REFERENCES CITED IN THE DESCRIPTION



    This list of references cited by the applicant is for the reader's convenience only. It does not form part of the European patent document. Even though great care has been taken in compiling the references, errors or omissions cannot be excluded and the EPO disclaims all liability in this regard.

    Patent documents cited in the description