KR100700722B1 - Organic light multi-face emitting diode with multi-layer - Google Patents

Abstract

An organic electroluminescent light emitting device having a multilayer film structure is disclosed. The organic EL device having a multilayer structure according to the present invention can obtain red, green, blue, and white light sources by using a double-sided organic EL device and a one-side organic EL device that are self-emission and can be used as surface light sources. The present invention relates to a field-sequential color type liquid crystal display and a separate stacked organic electroluminescent device for a backlight light source. The organic electroluminescent device emits light at the same time. It is formed of a light emitting one-side organic electroluminescent device, and sequentially stacking a double-sided organic electroluminescent device having a red and blue light emitting layer and a single-sided organic electroluminescent device having only a green light emitting layer, between the green light emitting layer and the red, blue light emitting layer and red Ultra-thin film to be a negative electrode or a positive electrode on top of the blue light emitting layer A transparent electrode including a metal electrode layer is configured, and the one-side light emitting device includes a reflective layer of a metal material having a large reflectance between the substrate and the transparent electrode before the green light emitting layer is formed. Therefore, according to the present invention, it is possible to obtain an output light source having excellent color reproducibility and high resolution and high brightness, and to be miniaturized and thinned, and to realize various types of light sources and display elements, and to realize inexpensive manufacturing cost. There is an effect such as.

ITO, FIELD SEQUENTIAL COLOR, Liquid Crystal Display (LCD), Backlight Unit

Description

ORGANIC LIGHT MULTI-FACE EMITTING DIODE WITH MULTI-LAYER}

1 is a cross-sectional view of a conventional liquid crystal display device.

2 and 3 are cross-sectional view of each type of backlight unit of FIG.

4 is a cross-sectional view of a conventional field sequential color liquid crystal display device.

5 is an exemplary view showing a comparison between a general light emitting pixel and a field sequential color light emitting pixel in a display device.

6 is a schematic configuration diagram for implementing an organic electroluminescent multi-surface light emitting device having a multilayer film configuration according to the present invention as a backlight unit.

6A is a cross-sectional view illustrating the configuration of the one-side organic electroluminescent device of FIG. 6.

6B is a cross-sectional view of the double-sided organic electroluminescent device of FIG. 6.

7A and 7B are exemplary perspective views showing before and after the sealing fastening process of the double-sided and one-sided organic electroluminescent devices according to the present invention, respectively.

8 is a graph showing red, green and blue emission spectra of a conventional organic electroluminescent device.

9 is a graph illustrating emission spectra of a state in which a red light emitting layer and a blue light emitting layer are respectively applied to the second and third light emitting units of FIG. 6B.

FIG. 10 is a graph illustrating emission spectra of a state in which a green light emitting layer, a red light emitting layer, and a blue light emitting layer are applied to the first, second, and third light emitting units of FIG. 6, respectively.

FIG. 11 is a graph illustrating emission spectra of the double-sided organic electroluminescent device and the one-sided organic electroluminescent device of FIG. 6 having a distance of 0.5 μm and 2.5 μm from each other. FIG.

FIG. 12 is a graph illustrating an emission spectrum when the distance between the double-sided organic electroluminescent device and the one-sided organic electroluminescent device of FIG. 10 is 20 μm. FIG.

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<Explanation of symbols for the main parts of the drawings>

600-backlight unit

      800-double-sided organic electroluminescent device 700-single-sided organic electroluminescent device

611-First light emitting unit 612-Second light emitting unit

            613-third light emitting unit

620-Board

 630-Light Diffusion 640-Sealant

650-Hygroscopic

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an organic electroluminescent light emitting device having a multilayer film structure for use as a field sequential color type liquid crystal display and a backlight light source.

In general, flat displays can be roughly divided into a light emitting type and a light receiving type.

The above-described light emitting display includes a flat cathode ray tube, a plasma display panel, an electroluminescent device, a light display panel, and the like. As a display, a liquid crystal display is a typical example.

Herein, the liquid crystal display 10 (LCD: Liquid Crystal Display) is formed by encapsulating the liquid crystal 12 between two glass substrates, and controlling the amount of light passing through the substrate by controlling the voltage intensity thereto. A display device using the electro-optical properties of liquid crystals (see FIG. 1).

Referring to FIG. 1, the liquid crystal display device 10 will be described in more detail. The liquid crystal display device 10 includes a backlight unit 11, a liquid crystal 12, and a color filter 13. 12) does not emit light by itself and has only a function of merely adjusting the amount of light, so there is a problem in that the output image cannot be easily observed in a dark place.

Accordingly, the backlight unit 11 is used to observe the output image even in a dark place. The backlight unit 11 has a direct light type and an edge light type according to the arrangement of the light source. It is divided into (Edge Light Type). (See FIGS. 2 and 3)

Looking at the direct emission type and the edge emission type with reference to FIGS. 2 and 3, in the direct emission type backlight unit 20, a plurality of light sources 21 are arranged at regular intervals, and are below the light source 21. As such, the reflecting plate 22 and the protective plate 23 are sequentially positioned, and the light diffusing plate 24 and the prism plate 25 are sequentially disposed above the light source 21. The edge emitting type backlight unit 30 includes a light diffusion plate 34 and a prism plate 35 above the light guide plate 32, and a reflection plate 33 below the light guide plate 32. The light guide plate 32 includes a light source 31 provided with a light source cover 36 for condensing light on a portion of the light guide plate 32 adjacent to the side surface.

In this case, the light sources 21 and 31 generally use a cold cathode fluorescent lamp (CCFL) and the like, and they are all linear light sources instead of surface light sources, so that the reflector plate 22 described above may be used to achieve uniformity of light. 33, the light guide plate 32, the diffusion plates 24 and 34, and the prism plates 25 and 35, and have a complicated structure composed of various optical sheets.

As a result, as shown in FIG. 1, in the liquid crystal display 10, a liquid crystal 12 for adjusting gray scale is positioned on the top of the backlight unit 11 to express color. Color filter 13 had to be provided.

In the conventional liquid crystal display, the power consumption of the backlight unit occupies 50 to 70% of the total power consumption, and the light emitted from the light source disappears about 90% while passing through the optical sheet, the liquid crystal, and the color filter. As a result, a lot of closures occurred as only 10% of them were exposed to the outside.

Meanwhile, FIG. 4 is a cross-sectional view of a liquid crystal display device according to a conventional field sequential color method, and an improved light emission method to compensate for a problem of a conventional liquid crystal display device, that is, low color reproducibility and limited viewing angle. It is shown.

Here, the biggest feature of the above-mentioned field sequential color method is that the backlight portion and the color filter are integrally combined.

Referring to FIG. 4, the LEDs of red (41), green (42), and blue (43) layers are sequentially stacked as light emitting sources, and the LEDs are controlled to emit light at high speed. It is implemented to control the color by adjusting the scale. That is, the present invention refers to a method of implementing color using a temporal blending method rather than a spatial blending method of a conventional liquid crystal display.

The light emitting device adopted in the field sequential color method serves as a display by itself, and color can be realized through red, green, and blue light emitting devices without passing through a color filter, and thus color reproduction rate of about 87% is achieved. Achievement can be achieved and the resolution per same area is improved by 9 times over the light emitting method of the conventional liquid crystal display.

FIG. 5 is a contrast diagram illustrating an example in which a light emitting pixel 500 and 510 of a conventional liquid crystal display and a field sequential color method are compared and implemented on the same unit area.

In the conventional liquid crystal display, a total of three pixels of red 501, green 502, and blue 503, which are three primary colors of light, form one pixel 500, but the field sequential color method ( 510 has an advantage that a high resolution can be realized by one pixel 511 forming one pixel 511.

However, since the above-described red, green, and blue light emitting sources are implemented with LEDs, the advantages of excellent color reproduction and durability are recognized, but still require a lot of power consumption, and there is a problem in that medium and large size are difficult.

In addition, as described above, the LED is used as a light emitting source, and the color breaking phenomenon (rainbow phenomenon: a phenomenon of visual afterimage) is intensified, which increases eye fatigue, which makes it difficult to watch for a long time. Another closure of the back occurred.

The present invention has been made in view of the above-mentioned problems, and the liquid crystal is formed by sealing the two-sided organic electroluminescent device which emits light at the same time and the one-side organic electroluminescent device at which one-way light emission is maintained at a constant distance from each other. An object of the present invention is to provide an organic electroluminescent multi-surface light emitting device having a multilayer film configuration that can be variously applied, such as a display device, a backlight unit, a display device of a field sequential color method, and the like.

Another object of the present invention is to reduce the size, medium and large size, thin film, etc. according to the manufacturing purpose of the manufacturer, it is possible to prevent the damage of organic matter and to extend the life of the multi-layer film configuration that is implemented to significantly reduce the manufacturing cost An organic electroluminescent device having a multi-sided light emitting device is provided.

An organic electroluminescent multi-surface light emitting device having a multilayer film configuration according to the present invention for achieving the above object,

A double-sided organic electroluminescent device having a second light emitting unit and a third light emitting unit emitting high luminance mono color in both directions; A first organic light emitting device having a first light emitting unit for emitting a high luminance mono color to emit light in one direction and stacked on the double-sided organic electroluminescent device; An ultra-thin metal electrode layer interposed between an upper portion of the first light emitting portion, the second light emitting portion, and the third light emitting portion; A reflective layer interposed between the substrate of the one surface organic EL device and the first light emitting part; A moisture absorbent inserted into a substrate on which the double-sided organic EL device and the one-sided organic EL device are opposed to each other; A sealant of a transparent material which is coated on an outer surface of the substrate to which the moisture absorbent is inserted and seals and fastens the light emitting devices; And a light diffusing layer formed on a light emitting part surface of the substrates of the light emitting devices or implemented as a separate sheet layer.

Here, the light emitting portions of each of the double-sided organic electroluminescent device and the one-sided organic electroluminescent device may be formed by stacking a plurality of light emitting layers having the same color.

The light emitting layers may include one or more organic light emitting materials, and the organic light emitting material may include a host light emitting material selected from Alq 3, NPB, CBP, and DPVBi; A dopant luminescent material selected from green dopant C545T, red dopant DCM2, and DCJTB, blue dopant perylene; This is preferably doped.

At this time, each of the substrates of the light emitting device, it is preferable to comprise a thin film silicon wafer and a glass or flexible synthetic resin material,

The light emitting parts may be formed of an organic light emitting layer structure in which a transparent positive electrode layer, a hole injection layer, a hole transport layer, a light emitting layer, a hole limiting layer, an electron transport layer, and an electron injection layer are sequentially stacked on the substrate.

And, on the light emitting layer, LiF (0.3 ~ 2 nm) / Al (0.5 ~ 5 nm) / Ag (1 ~ 20 nm), Ca / Ag, or Ag / Ca is formed by laminating one or more, thickness It is preferable that the ultra-thin metal electrode layer of about 0.1 to 30 nm is additionally provided.

At this time, the ultra-thin metal electrode layer, the transparent electrode ITO is further formed on the upper surface, it is ideal that the plasma treatment for a predetermined time using oxygen, argon and nitrogen ions at atmospheric pressure or vacuum.

In addition, the reflective layer is preferably implemented in Al, Cr, Ag, Ni APC (Ag, Pd, Cu alloy).

Preferably, the double-sided organic electroluminescent device and the one-sided organic electroluminescent device are more preferably fastened sealingly so as to maintain an interval of about 0.5 μm to 20 μm.

On the other hand, the light diffusion layer is implemented as a diffusion sheet in the form of a film having a high refractive index, or the epoxy resin of a transparent material having a high refractive index is preferably implemented to a thickness of about 1 ㎛ ~ 1 mm on the substrate,

The light diffusion layer may be made by adding a powder of SiO 2 component to the epoxy resin of the transparent material at an appropriate ratio.

Preferably, the transparent electrode layer is preferably made by photo-patterning in a uniform shape.

As a manufacturing method of an organic electroluminescent multi-light emitting device having a multilayer film configuration according to the present invention having the above-mentioned structural features,

a) cleaning the transparent substrate, and then forming an anode electrode on the substrate;

b) sequentially forming a hole injection layer, a hole transporting layer, a light emitting layer, a hole limiting layer, an electron transporting layer, an electron injection layer on the anode electrode to form a light emitting part;

c) forming a transparent negative electrode or a transparent positive electrode or a transparent negative electrode and a positive electrode using ITO on the organic light emitting film;

d) depositing a metal selected from LiF / Al, Ag, Ca, Mg to a thickness of 0.1 to 30 nm between the light emitting part and the transparent electrode to form an ultra thin metal electrode layer;

e) sealingly fastening the double-sided organic electroluminescent device and the one-sided organic electroluminescent device formed by the steps a) to d) to maintain a distance of 0.5 to 20 μm;

f) forming a light diffusion layer on a light emitting surface of the substrate;

It is preferably made to include.

In any one of the steps a) to e), the double-sided and one-sided organic electroluminescent elements sealingly fastened to each other are designed to have different light emitting regions, and the electrode pads connected to the electrode layers do not overlap each other. It is good to be formed at another position.

Here, in any one of the steps a) to e), further comprising the step of forming a groove on the substrate in the step e) the hygroscopic (BaO, CaO, MgO) in the groove It is preferred that the step of injecting into is carried out.

In addition, the step b) is selected from vacuum thermal vapor deposition, laser beam deposition, ink jet deposition, color patterning deposition method is implemented,

In step c), RF sputter, RF grid sputter, DC sputter, DC pulse sputter, DC pulse sputter, ALD (atomic layer deposition), PEALD (plasma enhanced atomic) layer deposition).

Preferably, the step e) is ideally carried out in a high purity nitrogen atmosphere or vacuum.

On the other hand, step e),

i) inserting and aligning two organic electroluminescent elements in a fixing frame (Zig),

ii) applying and combining the absorbent insert and sealant,

iii) preferably cutting the upper substrate and the lower substrate at the same time.

As another manufacturing method of the organic electroluminescent light emitting device having the multilayer film structure according to the present invention,

a) disposing two organic light emitting elements so as to face each other, and then forming a pattern using PR, SiO ₂ , and SiN _x on mutually opposing substrates of the organic light emitting elements;

b) forming an organic material and a top negative electrode;

c) forming a SiO layer as a barrier layer on the uppermost negative electrode;

d) forming a thin film protective layer using Ca, CaO, Ba, BaO, Mg, MgO;

e) applying and inserting a sealant and a moisture absorbent along the edge surface of the substrate with a constant distance between the two organic electroluminescent elements, and sealing sealing the organic electroluminescent element;

It may be implemented to include.

As another manufacturing method of the organic electroluminescent light emitting device having the multilayer film structure according to the present invention,

a) disposing two organic light emitting devices so as to face each other, and then patterning PR, SiOx, and SiNx in a mesh shape or a tile shape on opposite substrates of the organic light emitting devices;

b) laminating a light emitting layer, a barrier layer and a protective layer on the pattern formed by step a);

c) inserting an absorbent and a sealant along the pattern edge formed by the step a) to mutually fasten the two organic EL devices;

It may be implemented to include.

Hereinafter, an organic EL device having a multilayer structure according to the present invention and a method of manufacturing the same will be described in detail with reference to the accompanying drawings.

FIG. 6 is a schematic block diagram of an organic electroluminescent light emitting device having a multilayer structure according to the present invention implemented as a field sequential color liquid crystal display and a backlight unit used therein, and FIGS. 6A and 6B are FIGS. Fig. 1 is a cross-sectional view of each of the organic EL device on one side and the organic EL device on both sides.

6 to 6B, the organic electroluminescent device 600 having a multi-layered film structure according to the present invention, as shown in FIG. 6A, is a surface organic electroluminescent device 700 which emits light in only one direction and as shown in FIG. 6B. An absorbent on both sides of the organic EL device 800 which emits light in both up and down directions, and a portion of the substrate 620 and 621 facing each other in a state where the light emitting devices 700 and 800 are spaced apart by a predetermined distance in the vertical direction. 650 is inserted, and sealant 640 such as epoxy of a transparent material is applied along its outer surface to integrally seal and fasten the above-described light emitting devices 700 and 800 (see FIG. 6).

Referring to FIG. 6A, the one surface organic EL device 700 will be described in more detail. The first electrode 661, which is a positive electrode formed on the substrate 620, and the first light emitting units 601 and 602, which are organic material films, are described. 604, 605, 606, 651, and a transparent second electrode 663, which is a negative electrode.

Here, the substrate 620 is a transparent or opaque material, and the positive electrode 661 that is the first electrode is patterned with a black matrix PR on the upper surface of the substrate 620. The first electrode 661 is formed of a transparent conductive film such as indium tin oxide (ITO) and the like, and has a reflective layer 664 having excellent reflection efficiency between the substrate 620 and the first electrode 661 (eg, For example, metals such as Cr, Al, Ag, Ni, and the like) are interposed.

In this case, the reflective layer 664 is formed in a thin film form having a predetermined thickness by general vacuum thermal vapor deposition or sputtering, and the first electrode 661 is also formed in a thin film form having a predetermined thickness by a general sputtering method. The forming process is formed by a photoresist (PR) or the like in a predetermined pattern, and then plasma treatment for a predetermined time with oxygen and nitrogen ions under atmospheric pressure or vacuum to obtain a high work function. do.

Subsequently, the following organic material film is stacked in a multilayer structure on the substrate 620 on which the first electrode 661 is formed.

More specifically, on the substrate on which the first electrode 661 is formed, a hole injection layer 601 made of CuPC, MTDATA, etc., a hole transport layer 602 made of NPB, TPD, etc., and Alq3 or Alq3: C545T. The first light emitting layer 651, which is a green light emitting layer made of (0.5%), the hole limiting layer 604 made of BCP or BAlq, the electron transport layer 605 made of Alq3, and LiF, BCP: Cs. The electron injection layer 606 to be implemented is continuously deposited by vacuum thermal evaporation to form the first light emitting part 611.

Subsequently, in the forming of the transparent electrode 663, which is a negative electrode formed on the first light emitting part 611, an ultra-thin metal composed of LiF / Al / Ag or Ca / Ag to minimize the damage of the organic thin film. The electrode layer 662 is formed by the aforementioned vacuum thermal vapor deposition method.

A transparent second electrode 663 made of transparent ITO is formed on the ultra-thin metal electrode layer 662 in a sputtering manner in a sputter chamber in which an ITO target is installed.

Looking at the configuration and manufacturing method of the double-sided organic electroluminescent device 800 with reference to Figure 6b, it is characterized by consisting of two light emitting parts, that is, the second light emitting portion 612 and the third light emitting portion (613).

The double-sided organic electroluminescent device 800 includes a positive electrode 665 formed on the substrate 621, an organic material layer 601, 602, 604, 605, 606, 652, a negative electrode, and a positive electrode. An electrode 666 is included.

In this case, the organic material layers 601, 602, 604, 605, 606, and 653, which are the third light emitting units 613, are formed on the transparent electrode 666, and then, as the negative electrode on the organic material layer, 667).

In more detail, the substrate 621 of the organic EL device 800 is made of a transparent material, and the positive electrode 665, which is a third electrode formed on the substrate 621, is also transparent as ITO. Is formed.

The ITO is preferably formed in a predetermined thin film form by a general sputtering method, and the third electrode 665 is a photoresist (Photo Resist: PR) which is the same method as the one-side organic electroluminescent device 700 described above. After forming in a predetermined pattern by using a plasma treatment for a predetermined time with oxygen and nitrogen ions at atmospheric pressure or vacuum to obtain a high work function.

Thereafter, the method described above is performed on the substrate on which the third electrode 665 is formed, that is, in the same manner as the first light emitting part 611, but as the second light emitting layer 652 of the second light emitting part 612. Is implemented to emit red light using two organic light emitting materials such as Alq3: DCJTB (1%).

In addition, a fourth electrode 666 is formed on the second light emitting part 612, and the fourth electrode 666 is also formed on the one surface organic electroluminescent device 700 of FIG. 6A. The ultra-thin metal electrode layer 662 is formed between the fourth electrode 666 and the second light emitting part 612 by the same method as described above.

Preferably, the fourth electrode 666 is plasma-treated for a predetermined time in the same manner as described above to obtain a high work function.

Subsequently, the third light emitting unit 613 is formed on the fourth electrode 666 in the same manner as the first and second light emitting units 611 and 612, and the blue light is implemented in implementing the third light emitting layer 653. There is a characteristic that an organic material such as DPVBi is configured to emit light.

The fifth electrode 667 is formed on the third light emitting part 613 by the method as described above, and the aforementioned method is provided between the fifth electrode 667 and the third light emitting part 613. The ultra thin metal electrode layer 662 is formed.

According to such a process, the double-sided organic electroluminescent device 800 in which the emitted light is simultaneously emitted to the front and rear surfaces of the substrate 621 can be manufactured.

8 and 9 show organic electroluminescence spectra of an organic electroluminescent multi-surface light emitting device having a multilayer film structure produced by the above-described process.

FIG. 8 illustrates emission spectra measured by manufacturing red, green, and blue light emitting units, each of which has one light emitting layer, by using the one-side organic electroluminescent device 700. The first electrode on the substrate 620 is 120 nm thick. NPB 60 nm as the hole transport layer, Alq3: DCJTB (1%) for red emission, Alq3 for green emission, and DPVBi for blue emission, respectively. 30 nm thick, Alq3 30 nm was formed as an electron transport layer, and ITO 60 nm was formed as an anode on the electron transport layer. An ultra-thin metal LiF 1 nm, Al 2 nm and Ag 10 nm were respectively laminated to form a translucent metal.

9 illustrates a double-sided organic electroluminescent device 800, wherein Alq3: DCJTB (1%, 30 nm), which is a red organic light emitting material, is used as the second light emitting layer 652 of the second light emitting unit 612. The emission spectrum obtained by applying DPVBi (30 nm) is illustrated as the third emission layer 653 of the third emission unit 613. The hole transport layer, the electron injection layer, the ultra-thin metal electrode layer, and the transparent electrode were manufactured with the same organic materials and thickness as above, and the ITO 666, which is a transparent electrode interposed between the light emitting layers, was used for a predetermined time using oxygen and nitrogen ions in a vacuum state. It is manufactured to have a high work function by plasma treatment.

Hereinafter, a process of sealingly coupling the double-sided organic electroluminescent device 800 and the one-side organic electroluminescent device 700 by the above-described process will be described in more detail.

Through the above-described process, a single-sided organic electroluminescent device 700 having a light emitting layer composed of a single layer and a double-sided organic electroluminescent device having a light emitting layer having two multilayered structures are manufactured, respectively.

Between the substrates of the two one-sided and double-sided organic electroluminescent devices 700 and 800, a sealant 640 such as epoxy of a transparent material is used to prevent the inflow of moisture and oxygen in the device. And a step of inserting an absorbent 650 on the substrate between the sealant 640 and the organic light emitting film to remove residual moisture and oxygen. One or two light emitting devices 700 and 800 are sealed to each other.

Here, when the moisture absorbent is inserted, processing is performed on the substrate of each of the light emitting elements 700 and 800 or any one of the substrates by forming a scratch pattern such as a scratch pattern. Afterwards, the moisture absorbent is injected into the groove to prevent leakage and flow of the moisture absorbent. In addition, when the two light emitting devices 700 and 800 are combined, the spacers are inserted between the light emitting devices 700 and 800 so that the interval may be about 1 μm.

However, the sealant 640 such as a transparent epoxy may be applied not only to the edges of the substrates 620 and 621 but also to the organic light emitting film without using the above-described method, so that water and oxygen may be completely removed from the beginning. In such a method, when the firing process is performed for a long time at a relatively low temperature during firing, the organic light emitting film may be prevented from being damaged.

7A and 7B are exemplary views illustrating a cutting process in a state in which the light emitting devices 700 and 800 are coupled after completing the above process.

Referring to FIG. 7A, one side of the organic electroluminescent element 711 is manufactured as the upper plate 701, and the two-sided organic electroluminescent element 721 is separately manufactured as the lower plate 702. (zig) (731).

Subsequently, the upper plate 701 and the lower plate 702 are accurately aligned to insert and apply a moisture absorbent and a sealant as shown in FIG. 6, and seal and fasten them as shown in FIG. 7B.

After sealing and fastening as described above, as shown in FIG. 7B, the upper and lower plates may be scribed along the cutting lines 741 to facilitate mass production.

When combining the double-sided organic electroluminescent element and the one-side organic electroluminescent element as described above is preferably carried out in a high-purity nitrogen atmosphere or vacuum.

10 is a light emission obtained by applying a green light emitting source to the first light emitting unit, a red light emitting source to the second light emitting unit, and a blue light emitting source to the third light emitting unit. The graph of the spectrum is shown.

In contrast to FIGS. 10 and 8 (graph showing emission spectra of single-layer organic electroluminescent devices), the emission spectrum of an organic electroluminescent multi-layer light emitting device having a multilayered film structure according to the present invention has a color purity higher than that of a single-layer organic electroluminescent device. Excellent implementation can be observed. In addition, it can be seen that the emitted light is emitted relatively more than that of the single layer, and as the amount of light is also large, it can be observed that all of red, green, and blue are emitted at high luminance.

11 and 12 illustrate emission spectra according to the spacing between the two-sided and one-sided organic electroluminescent devices in combining two double-sided and one-sided organic electroluminescent devices.

Here, when the interval is 0.5 ㎛, 2.5 ㎛ it can be seen that the shape of the spectrum does not change significantly. However, since the green light source is reduced when the interval is 20 μm, the range of the interval is preferably set to about 0.5 μm to 20 μm.

Meanwhile, another embodiment of the present invention is a light emitting device formed by the above-described process, and a process of forming a field sequential color liquid crystal display and a backlight light source used therein will be described below.

As shown in FIG. 6, when a liquid crystal panel (not shown) is installed at a portion where light is output by combining the double-sided organic electroluminescent device 800 and the one-side organic electroluminescent device 700, the LCD is used for a liquid crystal display using a field sequential color method. Can be.

In more detail, the first, second and third light emitting units 611, 612, and 613 may be emitted to emit green, red, and blue light, respectively, in the double-sided organic electroluminescent device and the single-sided organic electroluminescent device. .

When the red, green, and blue light emission are sequentially operated for a short time, red, green, and blue light are respectively output. When the red, green, and blue light are sequentially operated, white light is output. Thus, the emitted light is gray through the attached liquid crystal panel. By adjusting the gray scale, the gray scale can be applied to a display such as a liquid crystal display of a field sequential color method.

In the method of forming a backlight light source used in the liquid crystal display device, as shown in FIG. Coating or inserting the light diffusing layer 630 improves the uniformity of the light and at the same time it is possible to design and manufacture a backlight unit for obtaining a high brightness output light source.

As mentioned above, if it is based on this invention, the following effects can be acquired.

As a display such as a liquid crystal display device, by using an organic electroluminescent element, high viewing angle, fast response speed, and low power driving are possible;

By using the field sequential color system, the process of forming a color filter on the upper surface of the liquid crystal can be omitted, while the color reproduction is excellent;

By using the field sequential color method, as the transition from the conventional spatial division method to the time division method is achieved, a liquid crystal display device having a small size and a high resolution can be manufactured by increasing the resolution;

As a backlight used in a liquid crystal display device, components such as a reflecting plate, a prism sheet, and a light guide plate can be omitted, thereby minimizing light loss and significantly reducing the cost and process required for this;

The light emitting layer of the organic electroluminescent device can be composed of one layer or two layers instead of a multilayer, thereby increasing the low yield of the product produced when the multilayer is formed;

Compared with a liquid crystal display device and a backlight used therein, the organic electroluminescent device is a very useful invention having the effect of being thinner as the thickness becomes thinner.

Claims (22)

A double-sided organic electroluminescent device having a second light emitting unit and a third light emitting unit emitting high luminance mono color in both directions; A first organic light emitting device having a first light emitting unit for emitting a high luminance mono color to emit light in one direction and stacked on the double-sided organic electroluminescent device; An ultra-thin metal electrode layer interposed between an upper portion of the first light emitting portion, the second light emitting portion, and the third light emitting portion; A reflective layer interposed between the substrate of the one surface organic EL device and the first light emitting part; A moisture absorbent inserted into a substrate on which the double-sided organic EL device and the one-sided organic EL device are opposed to each other; A sealant of a transparent material which is coated on an outer surface of the substrate to which the moisture absorbent is inserted and seals and fastens the light emitting devices; A light diffusion layer formed on a light emitting portion of the substrate of the light emitting devices or implemented as a separate sheet layer; An organic electroluminescent multi-surface light emitting device having a multilayer film configuration comprising a. The method of claim 1, And the first light emitting unit is formed by sequentially stacking a hole injection layer, a hole transporting layer, a first light emitting layer, a hole limiting layer, an electron transporting layer, and an electron injection layer. The method of claim 2, And the first light emitting layer emits green light. The method of claim 1, The second light emitting unit is formed by sequentially stacking a hole injection layer, a hole transporting layer, a second light emitting layer, a hole limiting layer, an electron transporting layer, an electron injection layer, the third light emitting unit is a hole injection layer, a hole transporting layer, a third light emitting layer, An organic electroluminescent light emitting device having a multilayer film structure, characterized in that the hole confinement layer, the electron transport layer, and the electron injection layer are sequentially stacked. The method of claim 4, wherein And said second light emitting layer emits red light. The method of claim 4, wherein And the third light emitting layer emits blue light. According to claim 1, wherein the ultra-thin metal electrode layer has a multilayer film configuration, characterized in that LiF (0.3 ~ 2 nm) / Al (0.5 ~ 5 nm) / Ag (1 ~ 20 nm) or Ca / Ag is laminated Organic field multi-light emitting device. delete The method of claim 1, wherein the reflective layer, An organic electroluminescent multi-surface light emitting device having a multilayer film structure, which is formed of a material selected from Al, Cr, Ag, and Ni APC (Ag, Pd, Cu alloy). The method of claim 1, The double-sided organic light emitting device and the one-sided organic electroluminescent device, the organic electroluminescent device having a multi-layered film, characterized in that the sealing is fastened so that the interval of about 0.5 ㎛ to 20 ㎛. The method of claim 1, wherein the light diffusion layer, An organic electroluminescent device having a multi-layer film structure, characterized in that the film is a diffusion sheet in the form of a film having a high refractive index, or an epoxy resin of a transparent material having a high refractive index applied to a thickness of about 1 ㎛ ~ 1 mm on the substrate. delete delete delete delete delete delete delete delete delete delete delete

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