阅读说明：本技术 有机发光显示器 (Organic light emitting display ) 是由 金嗂瀚 金容铎 赵尹衡 朴钟珍 尹德灿 李伦圭 崔东昱 于 2020-02-04 设计创作，主要内容包括：提供了一种有机发光显示器。所述有机发光显示器包括：第一基体基底；多个有机发光二极管,设置在第一基体基底上；封装层,设置在有机发光二极管上；以及多个第一颜色转换过滤器,设置在封装层上。封装层包括：第一子无机层,设置在有机发光二极管上；第二子无机层,设置在第一子无机层上,并且具有与第一子无机层的折射率不同的折射率；有机层,设置在第二子无机层上；以及第三子无机层,设置在有机层上。(An organic light emitting display is provided. The organic light emitting display includes: a first base substrate; a plurality of organic light emitting diodes disposed on the first base substrate; an encapsulation layer disposed on the organic light emitting diode; and a plurality of first color conversion filters disposed on the encapsulation layer. The encapsulation layer includes: a first sub-inorganic layer disposed on the organic light emitting diode; a second sub inorganic layer disposed on the first sub inorganic layer and having a refractive index different from that of the first sub inorganic layer; an organic layer disposed on the second sub-inorganic layer; and a third sub-inorganic layer disposed on the organic layer.)

1. An organic light emitting display, comprising:

a first base substrate;

a plurality of organic light emitting diodes on the first base substrate;

an encapsulation layer on the plurality of organic light emitting diodes; and

a plurality of first color conversion filters on the encapsulation layer,

wherein the encapsulation layer comprises:

a first sub-inorganic layer on the plurality of organic light emitting diodes;

a second sub inorganic layer on the first sub inorganic layer and having a refractive index different from that of the first sub inorganic layer;

an organic layer on the second sub-inorganic layer; and

a third sub-inorganic layer on the organic layer.

2. The organic light emitting display of claim 1, wherein the refractive index of the second sub inorganic layer is greater than the refractive index of the first sub inorganic layer.

3. The organic light emitting display of claim 2, wherein the refractive index of the second sub inorganic layer is 1.5 to 1.57.

4. The organic light emitting display of claim 1, wherein a difference between the refractive index of the first sub inorganic layer and the refractive index of the second sub inorganic layer is 0.09 or less.

5. The organic light emitting display of claim 1, wherein the first sub-inorganic layer has a thickness ofOr greater, and the second sub-inorganic layer has a thickness ofOr smaller.

6. The organic light emitting display of claim 1, further comprising an interlayer insulating layer between the plurality of organic light emitting diodes and the encapsulation layer, wherein the interlayer insulating layer comprises an inorganic material.

7. The organic light emitting display of claim 6, wherein the interlayer insulating layer has 1.4 to2.5 refractive index andor a smaller thickness.

8. The organic light emitting display of claim 1, wherein the first color conversion filter comprises quantum dots.

9. The organic light emitting display of claim 1, further comprising a first cover layer and a second cover layer between the encapsulation layer and the plurality of first color conversion filters, wherein each of the first cover layer and the second cover layer has a thickness ofOr smaller.

10. The organic light emitting display of claim 9, wherein the first cap layer has a refractive index of 1.55 to 1.65, the second cap layer has a refractive index of 1.4 to 2.0, and the second cap layer directly contacts the plurality of first color conversion filters.

11. The organic light emitting display of claim 1,

wherein the encapsulation layer further comprises a fourth sub-inorganic layer on the third sub-inorganic layer, and

wherein a refractive index of the fourth sub inorganic layer is greater than a refractive index of the third sub inorganic layer.

12. The organic light emitting display of claim 11, wherein the refractive index of the fourth sub inorganic layer is 1.55 to 1.65, and the thickness of the fourth sub inorganic layer isOr smaller.

13. The organic light emitting display of claim 1, wherein the encapsulation layer further comprises:

a fifth sub inorganic layer between the plurality of organic light emitting diodes and the first sub inorganic layer; and

a sixth sub-inorganic layer located between the organic layer and the third sub-inorganic layer.

14. The organic light emitting display of claim 13, wherein each of the fifth and sixth sub inorganic layers has a thickness ofOr smaller.

15. The organic light emitting display of claim 1, wherein each of the plurality of organic light emitting diodes comprises:

a first electrode on the first base substrate;

a second electrode on the first electrode; and

a plurality of light emitting layers between the first electrode and the second electrode.

16. The organic light emitting display of claim 1, further comprising:

a third cover layer on the plurality of first color conversion filters; and

a plurality of second color conversion filters on the third cap layer.

17. The organic light emitting display of claim 16, wherein each of the plurality of first color conversion filters is a wavelength conversion pattern and each of the plurality of second color conversion filters is a color filter.

18. An organic light emitting display having a non-light emitting region and a plurality of color regions defined therein, the organic light emitting display comprising:

a plurality of organic light emitting diodes positioned in the plurality of color areas;

an encapsulation layer on the plurality of organic light emitting diodes; and

a wavelength conversion pattern on the encapsulation layer and in at least one of the plurality of color regions,

wherein the encapsulation layer comprises:

a first inorganic layer on the plurality of organic light emitting diodes;

an organic layer on the first inorganic layer; and

a second inorganic layer on the organic layer,

wherein the first inorganic layer includes a first sub-inorganic layer and a second sub-inorganic layer having a refractive index greater than that of the first sub-inorganic layer, and the second inorganic layer includes a third sub-inorganic layer and a fourth sub-inorganic layer having a refractive index greater than that of the third sub-inorganic layer.

19. The organic light emitting display of claim 18, wherein the plurality of color regions include a first color region, a second color region, and a third color region for emitting different colors of light, and the plurality of organic light emitting diodes are respectively located in the first color region, the second color region, and the third color region.

20. The organic light emitting display of claim 19, wherein the plurality of organic light emitting diodes are configured to emit the same color light.

21. The organic light emitting display of claim 20, wherein the first color region is for outputting red light, the second color region is for outputting green light, the third color region is for outputting blue light, and each of the plurality of organic light emitting diodes is for emitting blue light.

22. The organic light emitting display of claim 18, further comprising a fill layer between the encapsulation layer and the wavelength conversion pattern.

23. The organic light emitting display of claim 22, wherein the fill layer comprises an inert gas.

24. The organic light emitting display of claim 22, further comprising first and second cap layers between the wavelength conversion pattern and the fill layer, each of the first and second cap layers having a refractive index greater than a refractive index of the fill layer.

25. The organic light emitting display of claim 18, wherein the encapsulation layer comprises the first sub inorganic layer, the second sub inorganic layer, the organic layer, the third sub inorganic layer, and the fourth sub inorganic layer sequentially arranged.

Technical Field

The present disclosure relates to an Organic Light Emitting Display (OLED), and more particularly, to an OLED including a quantum dot color conversion filter.

Background

With the development of multimedia, display devices are becoming increasingly important. Accordingly, various types (e.g., various kinds) of display devices, such as Organic Light Emitting Displays (OLEDs) and Liquid Crystal Displays (LCDs), are being used.

In the display device, the OLED includes an organic light emitting diode as a self-light emitting element. The organic light emitting diode may include two electrodes facing each other and an organic light emitting layer interposed between the two electrodes. Electrons and holes supplied from the two electrodes may be recombined in the organic light emitting layer to generate excitons. When the generated excitons change from an excited state to a ground state, light may be emitted.

Since the OLED does not require a light source, the OLED consumes low power, can be made lightweight and thin, and has a wide viewing angle, high brightness and high contrast, and a fast response speed. Due to these desirable (e.g., high-quality) characteristics, OLEDs are attracting attention as next-generation display devices.

In addition, quantum dots are semiconductor particles of nanometer order having a size of several nanometers and having a quantum confinement effect. In the bulk state, quantum dots exhibit suitable (e.g., excellent) optical and electrical properties not possessed by typical semiconductor materials. Quantum dots can emit light when excited by energy (such as light), and the color of the emitted light varies according to the size of the particles.

With the quantum dots, a large-area and high-resolution display device having good color purity, suitable (e.g., excellent) color reproducibility, and good moving image characteristics can be achieved. Therefore, a great deal of research is being conducted.

Disclosure of Invention

Aspects of the present disclosure relate to an Organic Light Emitting Display (OLED) that improves luminance by matching refractive indexes of elements disposed on an organic light emitting layer.

However, aspects of the present disclosure are not limited to the aspects set forth herein. The foregoing and other aspects of the present disclosure will become more apparent to those of ordinary skill in the art to which the present disclosure pertains by reference to the detailed description of the present disclosure given below.

According to an embodiment, an organic light emitting display includes: a first base substrate; a plurality of organic light emitting diodes on the first base substrate; an encapsulation layer on the plurality of organic light emitting diodes; and a plurality of first color conversion filters on the encapsulation layer, wherein the encapsulation layer includes: a first sub-inorganic layer on the plurality of organic light emitting diodes; a second sub inorganic layer located on the first sub inorganic layer and having a refractive index different from that of the first sub inorganic layer (e.g., the refractive index of the second sub inorganic layer is different from that of the first sub inorganic layer); an organic layer on the second sub-inorganic layer; and a third sub-inorganic layer on the organic layer.

According to an embodiment, an organic light emitting display includes a non-light emitting region and a plurality of color regions. The organic light emitting display includes: a plurality of organic light emitting diodes respectively located in the plurality of color areas; the packaging layer is positioned on the organic light emitting diode; and a wavelength conversion pattern on the encapsulation layer and in at least one of the plurality of color regions, wherein the encapsulation layer includes: a first inorganic layer on the plurality of organic light emitting diodes; an organic layer on the first inorganic layer; and a second inorganic layer on the organic layer, wherein the first inorganic layer includes a first sub inorganic layer and a second sub inorganic layer having a refractive index greater than that of the first sub inorganic layer, and the second inorganic layer includes a third sub inorganic layer and a fourth sub inorganic layer having a refractive index greater than that of the third sub inorganic layer.

Drawings

The above aspects and other aspects of the present disclosure will become apparent from and more readily appreciated by reference to the following description of the embodiments, taken in conjunction with the accompanying drawings of which:

fig. 1 is a perspective view of an Organic Light Emitting Display (OLED) according to an embodiment;

FIG. 2 is a schematic cross-sectional view of the OLED taken along line I1-I1' of FIG. 1;

fig. 3 is a schematic plan view of an OLED according to an embodiment;

FIG. 4 is a cross-sectional view of the OLED taken along line I2-I2' of FIG. 3;

fig. 5 is an enlarged cross-sectional view of the organic light emitting diode shown in fig. 4;

fig. 6 is a sectional view of a modified example of the organic light emitting diode shown in fig. 5;

fig. 7 is a sectional view of a modified example of the organic light emitting diode shown in fig. 5;

fig. 8 is a schematic cross-sectional view illustrating an optical path between the second interlayer insulating layer and the second cap layer in the embodiment of fig. 4;

fig. 9 is a schematic cross-sectional view showing an optical path in another OLED as a comparative example of fig. 8;

fig. 10 is a schematic cross-sectional view of a portion of an OLED according to a first experimental example;

fig. 11 is a schematic cross-sectional view of a portion of an OLED according to a second experimental example;

fig. 12 is a schematic cross-sectional view of a portion of an OLED according to a third experimental example;

fig. 13 is a schematic cross-sectional view of a portion of an OLED according to a fourth experimental example;

fig. 14 is a schematic cross-sectional view of a portion of an OLED according to a fifth experimental example;

fig. 15 is a schematic cross-sectional view of a portion of an OLED according to a sixth experimental example;

fig. 16 is a cross-sectional view of an OLED according to an embodiment;

fig. 17 is a cross-sectional view of an OLED according to an embodiment; and

fig. 18 is a cross-sectional view of an OLED according to an embodiment.

Detailed Description

The features of the present disclosure and methods of accomplishing the same may be understood more readily by reference to the following detailed description of embodiments and the accompanying drawings. The presently disclosed subject matter may, however, be embodied in many different forms and should not be construed as limited to the embodiments set forth herein. Rather, these embodiments are provided so that this disclosure will be thorough and complete and will fully convey the concept of the presently disclosed subject matter to those skilled in the art, and the presently disclosed subject matter will be defined only by the appended claims and their equivalents. Like reference numerals refer to like elements throughout the specification.

It will be understood that when an element or layer is referred to as being "on," "connected to" or "coupled to" another element or layer, it can be directly on, connected or coupled to the other element or layer or intervening elements or layers may be present. In contrast, when an element is referred to as being "directly on," "directly connected to" or "directly coupled to" another element or layer, there are no intervening elements or layers present. As used herein, the term "and/or" includes any and all combinations of one or more of the associated listed items.

It will be understood that, although the terms first, second, etc. may be used herein to describe various elements, components, regions, layers and/or sections, these elements, components, regions, layers and/or sections should not be limited by these terms. These terms are only used to distinguish one element, component, region, layer or section from another element, component, region, layer or section. Thus, a first element, component, region, layer or section discussed below could be termed a second element, component, region, layer or section without departing from the teachings of the present disclosure.

The terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the presently disclosed subject matter. As used herein, the singular forms "a", "an" and "the" are intended to include the plural forms as well, unless the context clearly indicates otherwise. It will be further understood that the terms "comprises" and/or "comprising," when used in this specification, specify the presence of stated features, integers, steps, operations, elements, components, and/or groups thereof, but do not preclude the presence or addition of one or more other features, integers, steps, operations, elements, components, and/or groups thereof.

An Organic Light Emitting Display (OLED) according to various embodiments of the present disclosure is a device for displaying moving and/or still images and/or a device for displaying stereoscopic images. The OLED may be used as a display screen of a portable electronic device, such as a mobile communication terminal, a smart phone, a tablet computer, a smart watch, and/or a navigation system, and a display screen of various products, such as a television, a notebook, a monitor, a billboard, and/or the internet of things. However, embodiments of the present disclosure are not limited thereto, and the OLED may also be used as a display screen of other electronic devices without departing from the spirit of the present disclosure.

Hereinafter, embodiments of the present disclosure will be described in more detail with reference to the accompanying drawings. The same reference numbers or similar reference numbers will be used for the same elements in the drawings.

Fig. 1 is a perspective view of an OLED1 according to an embodiment. Fig. 2 is a schematic cross-sectional view of the OLED1 taken along line I1-I1' of fig. 1. Fig. 3 is a schematic plan view of an OLED1 according to an embodiment.

Referring to fig. 1 to 3, the OLED1 includes a display area DA and a non-display area NDA.

The display area DA is defined as an area where an image is displayed. Elements for displaying an image may be disposed in the display area DA.

In an embodiment, the display area DA may have a flat shape. The display area DA may be disposed in a central portion of the OLED 1. However, the position and shape of the display area DA are not limited to those shown in the drawings. In embodiments, the display area DA may be disposed at an edge of the OLED1, and/or at least a portion of the display area DA may be curved.

The display region DA includes a light-emitting region and a non-light-emitting region NLA.

The light emitting region is defined as a portion of the display region DA through which light is transmitted and viewed by a user. The light emitting region may include a plurality of color regions LA11 through LAmn. The color areas LA11 to LAmn may be arranged in a matrix (e.g., in the shape of a matrix). For example, the color areas LA11 to LAmn may be arranged in an n × m matrix. As exemplary color regions, a first color region LA11 in the first row and the first column, a second color region LA12 in the first row and the second column, and a third color region LA13 in the first row and the third column will be described below.

The color areas LA11 to LAmn may include a red light-emitting area, a green light-emitting area, and a blue light-emitting area. In some embodiments, a white light emitting region may also be provided. In an embodiment, the color areas LA11 through LAmn may include a cyan light-emitting area, a magenta light-emitting area, and a yellow light-emitting area instead of the red light-emitting area, the green light-emitting area, and the blue light-emitting area. A case where the light emitting region of the OLED1 includes a first color region LA11, a second color region LA12, and a third color region LA13 that emit red light, green light, and blue light, respectively, will be described below as an example. However, the colors (e.g., color types) and the arrangement order of the first color region LA11, the second color region LA12, and the third color region LA13 are not limited to this example.

In the present specification, blue light refers to light having a wavelength range of about 450nm to about 495nm, green light refers to light having a wavelength range of about 495nm to about 570nm, and red light refers to light having a wavelength range of about 620nm to about 750 nm.

The first, second, and third color areas LA11, LA12, and LA13 may be alternately arranged in the column direction and/or the row direction. Each of the first, second, and third color areas LA11, LA12, and LA13 may have a quadrangular shape.

The row direction as used herein denotes the first direction dr1, and the first direction dr1 is a horizontal direction in the drawing. The column direction as used herein denotes the second direction dr2, and the second direction dr2 is a vertical direction in the drawing. The row direction and the column direction are directions that intersect (e.g., cross) each other. That is, the first direction dr1 is a direction that intersects (e.g., crosses) the second direction dr 2. Further, the third direction dr3 represents a direction perpendicular to or intersecting the second direction dr2 and the first direction dr 1. That is, the third direction dr3 is a thickness direction of the OLED1 (e.g., a thickness direction of the first substrate 10). However, embodiments are not limited to the above-mentioned directions, and it should be understood that one of the first, second, and third directions dr1, dr2, dr3 is a direction perpendicular or intersecting (e.g., opposite) all other directions.

In one embodiment, the color areas LA11 through LAmn may have different sizes. In this case, the size of third color region LA13 may be larger than the size of first color region LA11, and the size of first color region LA11 may be larger than the size of second color region LA 12. However, the order of the sizes of the first color area LA11 through the third color area LA13 is not limited to this example.

The non-light emitting region NLA is defined as a region for separating the color regions LA11 to LAmn in the display region DA. That is, the non-light emitting region NLA may be a region through which light is not transmitted. The non-light emitting area NLA may surround each of the color areas LA11 to LAmn. For example, the non-light emitting area NLA may be in a mesh shape.

The non-display area NDA is defined as an area where no image is displayed. The non-display area NDA is disposed on at least one side of the display area DA. For example, the non-display area NDA may surround the display area DA. In an embodiment, the speaker module and the sensor module may be disposed in the non-display area NDA. In an embodiment, the sensor module may include at least one of a remote control sensor, an illuminance sensor, a proximity sensor, an infrared sensor, and an ultrasonic sensor.

The OLED1 may have a stacked structure including, for example, a first substrate 10, a second substrate 30 facing the first substrate 10, a filling layer 70 interposed between the first and second substrates 10 and 30, and a sealing part 50 bonding the first and second substrates 10 and 30 together at an edge of the filling layer 70.

The first substrate 10 may include elements and circuits for displaying an image, for example, pixel circuits (such as switching elements) and organic light emitting diodes. The first substrate 10 may be a display substrate.

The second substrate 30 may be positioned above the first substrate 10 and facing the first substrate 10. The second substrate 30 may be, but is not limited to, a color conversion substrate including a color conversion filter converting a color of light emitted from the first substrate 10.

The sealing part 50 may be located between the first substrate 10 and the second substrate 30. The sealing part 50 may be disposed in the non-display area NDA along edges of the first and second substrates 10 and 30. The first substrate 10 and the second substrate 30 may be bonded together by a sealing portion 50. The sealing part 50 may include, but is not limited to, an organic material such as epoxy resin.

The filling layer 70 may be located in a space between the first and second substrates 10 and 30, and surrounded by the sealing part 50. The filling layer 70 may fill a space between the first substrate 10 and the second substrate 30. The filling layer 70 may be made of a material that can transmit light. For example, the fill layer 70 may include a silicon-based organic material, an epoxy-acrylic-based organic material, and/or another suitable organic material (e.g., organic). In some embodiments, the filler layer 70 may be silicone rubber or an air layer. Here, the air layer may contain an inert gas (e.g., nitrogen or argon), or may contain various gas mixtures.

The stacked structure of the OLED1 will now be described in more detail with reference to fig. 4 and 5. The following description will be given based on the first color region LA11, the second color region LA12, and the third color region LA13 as exemplary color regions included in the light emitting region.

Fig. 4 is a cross-sectional view of the OLED1 taken along line I2-I2' of fig. 3. Fig. 5 is an enlarged cross-sectional view of the organic light emitting diode 310 shown in fig. 4.

The first substrate 10 will now be described in more detail.

The first substrate 10 includes a first base substrate 101, a plurality of switching elements TR1, TR2, and TR3 disposed on the first base substrate 101, a plurality of organic light emitting diodes 310 disposed on the switching elements TR1, TR2, and TR3, and an encapsulation layer 400 disposed on the organic light emitting diodes 310.

The display area DA and the non-display area NDA described above may be defined in the first substrate 10.

The first base substrate 101 may be a rigid substrate. Here, the first base substrate 101 may be one selected from a glass substrate, a quartz substrate, a glass ceramic substrate, a crystallized glass substrate, and a reinforced plastic.

The buffer layer 201 is disposed on the first base substrate 101. The buffer layer 201 serves to smooth the surface of the first base substrate 101 and to prevent or reduce the introduction of moisture and/or external air. The buffer layer 201 may be an inorganic layer. The buffer layer 201 may be a single layer or a plurality of layers.

The switching elements TR1, TR2, and TR3 are disposed on the buffer layer 201. Each of the switching elements TR1, TR2, and TR3 may be a thin film transistor. Each of the switching elements TR1, TR2, and TR3 shown in the drawings may be a driving thin film transistor.

The switching elements TR1, TR2, and TR3 may include a first switching element TR1, a second switching element TR2, and a third switching element TR 3. One or more switching elements TR1, TR2, or TR3 may be provided in each of the color regions LA11, LA12, and LA 13. For example, the first switching element TR1 may be disposed in the first color region LA11, the second switching element TR2 may be disposed in the second color region LA12, and the third switching element TR3 may be disposed in the third color region LA 13.

The switching elements TR1, TR2, and TR3 may include semiconductor layers a1, a2, and A3, gate electrodes G1, G2, and G3, source electrodes S1, S2, and S3, and drain electrodes D1, D2, and D3, respectively. For example, semiconductor layers a1, a2, and A3 are disposed on the buffer layer 201. The semiconductor layers a1, a2, and A3 may include amorphous silicon, polycrystalline silicon, low-temperature polycrystalline silicon, and/or an organic semiconductor. In an embodiment, the semiconductor layers a1, a2, and A3 may be an oxide semiconductor. In one embodiment, each of the semiconductor layers a1, a2, and A3 may include a channel region and source and drain regions disposed on both sides of the channel region and doped with impurities.

The gate insulating layer 211 is disposed on the semiconductor layers a1, a2, and A3. The gate insulating layer 211 may be an inorganic layer. The gate insulating layer 211 may be a single layer or a multi-layer.

Gate electrodes G1, G2, and G3 are disposed on the gate insulating layer 211. The gate electrodes G1, G2, and G3 may be made of a metal material having conductivity. For example, the gate electrodes G1, G2, and G3 may include molybdenum (Mo), aluminum (Al), copper (Cu), and/or titanium (Ti). Each of the gate electrodes G1, G2, and G3 may be a single layer or a multilayer.

The first interlayer insulating layer 212 is disposed on the gate electrodes G1, G2, and G3. The first interlayer insulating layer 212 may be an inorganic layer. The first interlayer insulating layer 212 may be a single layer or a plurality of layers.

Source electrodes S1, S2, and S3 and drain electrodes D1, D2, and D3 are disposed on the first interlayer insulating layer 212. The source electrodes S1, S2, and S3 and the drain electrodes D1, D2, and D3 are made of a metal material having conductivity. For example, the source electrodes S1, S2, and S3 and the drain electrodes D1, D2, and D3 may include aluminum (Al), copper (Cu), titanium (Ti), and/or molybdenum (Mo).

The source electrodes S1, S2, and S3 and the drain electrodes D1, D2, and D3 may be electrically connected to source and drain regions of the semiconductor layers a1, a2, and A3, respectively, through contact holes passing through the first interlayer insulating layer 212 and the gate insulating layer 211.

In one embodiment, the OLED1 may also include a storage capacitor and a switching transistor on the first base substrate 101.

The protective layer 220 is disposed on the source electrodes S1, S2, and S3, the drain electrodes D1, D2, and D3, and the first interlayer insulating layer 212. Here, the protection layer 220 covers the circuit unit including the switching elements TR1, TR2, and TR 3. The protective layer 220 may be a passivation layer or a planarization layer. The passivation layer may include SiO₂And/or SiN_xEtc., the planarization layer may comprise a material such as acrylic and/or polyimide. The protective layer 220 may also include both a passivation layer and a planarization layer. In this case, a passivation layer may be disposed on the source electrodes S1, S2, and S3, the leakage currentThe poles D1, D2, and D3, and the first interlayer insulating layer 212, and a planarization layer may be disposed on the passivation layer. The upper surface of the protective layer 220 may be flat.

The organic light emitting diode 310 may be disposed on the protective layer 220. The organic light emitting diodes 310 may be disposed in the color areas LA11, LA12, and LA13, respectively. The elements of each organic light emitting diode 310 will now be described in more detail.

A plurality of first pixel electrodes 311 may be disposed on the protective layer 220. The first pixel electrode 311 may be pixel electrodes disposed in color areas LA11, LA12, and LA13, respectively. In addition, the first pixel electrode 311 may be an anode of the organic light emitting diode 310.

The first pixel electrode 311 may be electrically connected to the drain electrodes D1, D2, and D3 (or the source electrodes S1, S2, and S3) disposed on the first base substrate 101, respectively, through vias passing through the protective layer 220.

The first pixel electrode 311 may include a material having a high work function. The first pixel electrode 311 may include Indium Tin Oxide (ITO), Indium Zinc Oxide (IZO), zinc oxide (ZnO), and/or indium oxide (In)₂O₃)。

In an embodiment, areas occupied by the first pixel electrode 311 in the color regions LA11, LA12, and LA13, respectively, may be the same in a plan view. That is, the first pixel electrode 311 in the color regions LA11, LA12, and LA13 may have the same surface area in plan view.

The pixel defining layer 330 is disposed on the first pixel electrode 311. The pixel defining layer 330 includes openings that at least partially expose the respective first pixel electrodes 311. In an embodiment, the openings may have different widths in color areas LA11, LA12, and LA 13. For example, the openings may have a smaller (e.g., reduced) width in the order of the openings of second color region LA12, the openings of first color region LA11, and the openings of third color region LA 13. That is, the area of the first pixel electrode 311 exposed by the pixel defining layer 330 may increase in the order of the third color region LA13, the first color region LA11, and the second color region LA 12.

The pixel defining layer 330 may include an organic material and/or an inorganic material. In an embodiment, the pixel defining layer 330 may include a material such as photoresist, polyimide resin, acrylic resin, silicon compound, and/or polyacrylic resin.

The organic light emitting layer 320 may be disposed on each of the first pixel electrodes 311 exposed by the pixel defining layer 330. For example, the organic light emitting layer 320 may have a structure in which a first hole transport layer HTL1, a first light emitting layer EL11, and a first electron transport layer ETL1 are sequentially stacked. In the embodiment, the organic light emitting layers 320 respectively disposed in the color areas LA11, LA12, and LA13 may all be blue organic light emitting layers.

The second pixel electrode 312 is disposed on the first electron transport layer ETL 1. The second pixel electrode 312 may be a common electrode disposed over the entire first base substrate 101 without distinguishing between the color areas LA11, LA12, and LA 13. In addition, the second pixel electrode 312 may be a cathode of each of the organic light emitting diodes 310.

The second pixel electrode 312 may include a material having a low work function. The second pixel electrode 312 may include Li, Ca, LiF/Al, Mg, Ag, Pt, Pd, Ni, Au, Nd, Ir, Cr, BaF₂Ba, or a compound or mixture thereof (e.g., a mixture of Ag and Mg). The second pixel electrode 312 may further include an auxiliary electrode. The auxiliary electrode may include a layer formed by depositing one of the above materials and a transparent metal oxide (such as ITO, IZO, ZnO, and/or ITZO) formed on the layer.

When the OLED1 is a top-emitting OLED, a thin conductive layer having a low work function may be formed as the second pixel electrode 312, and a transparent conductive layer (such as an ITO layer, an IZO layer, a ZnO layer, and/or In)₂O₃Layers) may be stacked on the thin conductive layer.

In each of the color regions LA11, LA12, and LA13, the first pixel electrode 311, the first hole transport layer HTL1, the first light emitting layer EL11, the first electron transport layer ETL1, and the second pixel electrode 312 may constitute (e.g., form) one organic light emitting diode 310.

The type (e.g., kind) and stacking order of elements of each organic light emitting diode 310 are not limited to those shown in the drawings. Various modified embodiments of the organic light emitting diode 310 may be applied to the OLED1, which will be described in more detail later with reference to fig. 6 and 7.

The second interlayer insulating layer 350 is disposed on the second pixel electrode 312. The second interlayer insulating layer 350 may be a single layer or a plurality of layers. When the second interlayer insulating layer 350 is formed as a single layer, the second interlayer insulating layer 350 may include an inorganic material (e.g., an inorganic substance), and when the second interlayer insulating layer 350 is formed as a plurality of layers, the second interlayer insulating layer 350 may be an organic-inorganic composite material. For example, the second interlayer insulating layer 350 may include a metal fluoride, a metal oxide, a metal nitride, and/or a metal oxynitride. The second interlayer insulating layer 350 may be formed by sputtering, Atomic Layer Deposition (ALD), and/or Chemical Vapor Deposition (CVD).

The thickness of the second interlayer insulating layer 350 may be aboutOr smaller. The second interlayer insulating layer 350 may have a first refractive index. For example, when the second interlayer insulating layer 350 is a single layer, the first refractive index may have a range of about 1.9 to about 2.5 for light of about 560nm (e.g., having a wavelength of about 560 nm). Throughout the specification, the expression "light" preceded by a number having a unit nm refers to light having a wavelength of the specified number. For example, the expression light of about 560nm refers to light having a wavelength of about 560 nm. When the second interlayer insulating layer 350 is a multilayer, the first refractive index may have a range of about 1.4 to about 2.5 for light of about 560 nm.

The second interlayer insulating layer 350 may improve light extraction of the organic light emitting diode 310. In an embodiment, the second interlayer insulating layer 350 may be omitted (e.g., not included). Hereinafter, the term "omitted" means that a feature is not included in a structure or description of the feature is not repeated.

The encapsulation layer 400 is disposed on the second interlayer insulating layer 350. In an embodiment in which the second interlayer insulating layer 350 is omitted, the encapsulation layer 400 may be directly disposed on the second pixel electrode 312.

The encapsulation layer 400 includes an inorganic layer. The encapsulation layer 400 may include a plurality of stacked layers. In the drawing, the encapsulation layer 400 is illustrated as a multilayer including a first inorganic layer 410, an organic layer 420, and a second inorganic layer 430 sequentially stacked on the second interlayer insulating layer 350.

The first inorganic layer 410 may be a multi-layer. In the current embodiment, the first inorganic layer 410 may have a structure in which a first sub inorganic layer 411, a second sub inorganic layer 412, and a third sub inorganic layer 413 are sequentially stacked. The first, second, and third sub inorganic layers 411, 412, and 413 may have the same refractive index or different refractive indices. In an embodiment, the thickness of the first inorganic layer 410 may be about 2 μm or less. That is, the sum of the thicknesses of the first, second, and third sub inorganic layers 411, 412, and 413 may be about 2 μm or less.

The first sub inorganic layer 411 is disposed on the second interlayer insulating layer 350. The first sub-inorganic layer 411 may include a metal oxide, a metal nitride, and/or a metal oxynitride.

The first sub-inorganic layer 411 may include a material having a second refractive index. For example, the second refractive index may have a range of about 1.4 to about 1.6 for light of about 560 nm. The second refractive index may be lower than the first refractive index, but is not limited thereto. That is, the first sub-inorganic layer 411 may be a substantially thinner material than the second interlayer insulating layer 350.

In this specification, sparse materials refer to materials having a relatively low refractive index and materials through which waves (e.g., light waves) propagate at a relatively fast speed. That is, a dense material is a material that is relatively denser (e.g., optically dense) than a sparse material. Dense and sparse materials are clearly understood as a relative concept between two materials.

The thickness of the first sub-inorganic layer 411 may be aboutOr smaller. The first sub-inorganic layer 411 may be, but is not limited to, a single layer. First sub-inorganic layer411 may be formed by sputtering, ALD, and/or CVD. In an embodiment, the first sub inorganic layer 411 may be omitted.

The second sub inorganic layer 412 is disposed on the first sub inorganic layer 411. The second sub inorganic layer 412 may be made of the same material as that of the first sub inorganic layer 411, or may include one of the materials exemplified in connection with the first sub inorganic layer 411.

The second sub-inorganic layer 412 may include a material having a third refractive index. For example, the third refractive index may have a range of about 1.4 to about 1.6 for light of about 560 nm. In an embodiment, the third refractive index may be substantially equal to the second refractive index.

The thickness of the second sub-inorganic layer 412 may be aboutOr larger. In an embodiment, the second sub inorganic layer 412 may be a single layer. The second sub inorganic layer 412 may be formed through the same process (e.g., the same kind of process, e.g., the same method) as that of the first sub inorganic layer 411, or may be formed through one of the processes illustrated in connection with the first sub inorganic layer 411.

When the first sub inorganic layer 411 and the second sub inorganic layer 412 include the same material and are formed through the same process (e.g., the same kind of process), the first sub inorganic layer 411 may be an element for increasing the thickness of the second sub inorganic layer 412.

The third sub inorganic layer 413 is disposed on the second sub inorganic layer 412. The third sub inorganic layer 413 may be made of the same material as that of the first sub inorganic layer 411, or may include one of the materials exemplified in connection with the first sub inorganic layer 411.

The third sub inorganic layer 413 may include a material having a fourth refractive index. For example, the fourth refractive index may have a range of about 1.5 to about 1.57 for light of about 560 nm. In an embodiment, the fourth refractive index may be higher than the third refractive index. In this case, the third sub inorganic layer 413 may be made of a substantially denser material than the second sub inorganic layer 412. However, the relationship between the magnitudes of the third refractive index and the fourth refractive index is not limited to this case.

The thickness of the third sub-inorganic layer 413 may be aboutOr smaller. In an embodiment, the third sub inorganic layer 413 may be a single layer. The third sub inorganic layer 413 may be formed through the same process (e.g., the same kind of process) as that of the first sub inorganic layer 411, or may be formed through one of the processes illustrated in conjunction with the first sub inorganic layer 411.

The organic layer 420 is disposed on the third sub-inorganic layer 413. The organic layer 420 may be made of a polymer such as photocurable acrylic, silicone, and/or epoxy. The organic layer 420 may be made of a material having an average transmittance of about 88% or more for light of about 400nm to about 780nm and an average transmittance of less than 10% for light of about 380nm to about 410 nm.

The organic layer 420 may have a fifth refractive index. The fifth refractive index may have a range of about 1.5 to about 1.6 for light of about 560 nm. In an embodiment, the fifth refractive index may be lower than the fourth refractive index. In this case, the organic layer 420 may be made of a substantially sparser material than the third sub-inorganic layer 413.

The thickness of the organic layer 420 may be about 2 μm to about 10 μm. In an embodiment, the organic layer 420 may be a single layer or a plurality of layers. The organic layer 420 may be formed by inkjet printing, slot coating, screen printing, and/or one-drop filling (ODF).

The second inorganic layer 430 is disposed on the organic layer 420. The second inorganic layer 430 may be a plurality of layers. In the current embodiment, the second inorganic layer 430 has a structure in which a fourth sub inorganic layer 431, a fifth sub inorganic layer 432, and a sixth sub inorganic layer 433 are sequentially stacked. The fourth, fifth, and sixth sub inorganic layers 431, 432, and 433 may have the same refractive index or different refractive indices. In an embodiment, the thickness of the second inorganic layer 430 may be about 2.6 μm or less. For example, the sum of the thicknesses of the fourth sub inorganic layer 431, the fifth sub inorganic layer 432, and the sixth sub inorganic layer 433 may be about 2.6 μm or less.

The fourth sub inorganic layer 431 is disposed on the organic layer 420. The fourth sub inorganic layer 431 may be made of the same material as that of the first sub inorganic layer 411, or may include one of the materials exemplified in connection with the first sub inorganic layer 411.

The fourth sub inorganic layer 431 may include a material having a seventh refractive index. For example, the seventh refractive index may have a range of about 1.5 to about 1.57 for light of about 560 nm.

The thickness of the fourth sub-inorganic layer 431 may be aboutOr smaller. In an embodiment, the fourth sub inorganic layer 431 may be a single layer. The fourth sub inorganic layer 431 may be formed through the same process (e.g., the same kind of process) as that of the first sub inorganic layer 411, or may be formed through one of the processes illustrated in conjunction with the first sub inorganic layer 411. In an embodiment, the fourth sub inorganic layer 431 may be omitted.

The fifth sub inorganic layer 432 is disposed on the fourth sub inorganic layer 431. The fifth sub inorganic layer 432 may be made of the same material as that of the first sub inorganic layer 411, or may include one of the materials exemplified in connection with the first sub inorganic layer 411.

The fifth sub-inorganic layer 432 may include a material having an eighth refractive index. For example, the eighth refractive index may have a range of about 1.6 to about 1.9 for light of about 560 nm. In an embodiment, the eighth refractive index may be equal to or higher than the seventh refractive index. In this case, the fifth sub inorganic layer 432 may be made of the same material as that of the fourth sub inorganic layer 431, or may be made of a substantially denser material than that of the fourth sub inorganic layer 431.

The thickness of the fifth sub-inorganic layer 432 may be about 2 μm to about 10 μm. In an embodiment, the fifth sub inorganic layer 432 may be a single layer. The fifth sub inorganic layer 432 may be formed through the same process (e.g., the same kind of process) as that of the first sub inorganic layer 411, or may be formed through one of the processes illustrated in conjunction with the first sub inorganic layer 411.

When the fourth sub inorganic layer 431 and the fifth sub inorganic layer 432 include the same material and are formed through the same process (e.g., the same kind of process), the fourth sub inorganic layer 431 may be an element for increasing the thickness of the fifth sub inorganic layer 432.

The sixth sub inorganic layer 433 is disposed on the fifth sub inorganic layer 432. The sixth sub inorganic layer 433 may be made of the same material as that of the first sub inorganic layer 411, or may include one of the materials exemplified in connection with the first sub inorganic layer 411.

The sixth sub-inorganic layer 433 may include a material having a ninth refractive index. For example, the ninth refractive index may have a range of about 1.55 to about 1.65 for light of about 560 nm. In an embodiment, the ninth refractive index may be higher than the eighth refractive index. In this case, the sixth sub inorganic layer 433 may be made of a substantially denser material than the fifth sub inorganic layer 432.

The thickness of the sixth sub-inorganic layer 433 may be aboutOr smaller. In an embodiment, the sixth sub inorganic layer 433 may be a single layer. The sixth sub inorganic layer 433 may be formed through the same process (e.g., the same kind of process) as that of the first sub inorganic layer 411, or may be formed through one of the processes illustrated in conjunction with the first sub inorganic layer 411.

The path of light emitted from each organic light emitting diode 310 may be adjusted by adjusting the refractive index of each layer in the encapsulation layer 400. This will be described in more detail later with reference to fig. 8.

The second substrate 30 will now be described in more detail. In the drawing, the OLED1 includes a third cover layer 513, a second cover layer 512, a second color conversion filter, a first cover layer 511, and a first color conversion filter sequentially disposed on the first substrate 10 and the filling layer 70 along a third direction dr 3. Since the second substrate 30 faces the first substrate 10, the direction of the stacking order of the second substrates 30 may be opposite to the direction of the stacking order of the first substrates 10. That is, the direction of the stacking order of the first substrates 10 may be the third direction dr3, and the direction of the stacking order of the second substrates 30 may be the opposite direction to the third direction dr 3. Therefore, for ease of description, only in the description of the second substrate 30, when a first element included in the second substrate 30 is stated to be disposed on a second element, it means that the first element is disposed in a direction opposite to the third direction dr3 from the second element.

The second substrate 30 includes a second base substrate 601, a first black matrix 521, a first color conversion filter, a first capping layer 511, a second color conversion filter, a second capping layer 512, a second black matrix 522, and a third capping layer 513 sequentially stacked. In addition, the second substrate 30 may further include a light-transmitting pattern 533 formed on the same layer as the second color conversion filter.

A light-emitting region including color regions LA11, LA12, and LA13, and a non-light-emitting region NLA may be defined in the second substrate 30.

The second base substrate 601 may be made of a light-transmitting material. The second base substrate 601 may be a glass substrate and/or a plastic substrate. In an embodiment, the second base substrate 601 may be a window member. The window member may protect the first and second substrates 10 and 30 from external scratches and the like.

The first black matrix 521 is disposed on the second base substrate 601. The first black matrix 521 may be disposed along a boundary of each of the color areas LA11, LA12, and LA13, and may block transmission of light. The first black matrix 521 may overlap the pixel defining layer 330. Throughout this disclosure, when two elements are described as being "stacked" on each other, unless otherwise defined, it means that the two elements are stacked on each other in the thickness direction of the OLED1 (i.e., the third direction dr 3). The first black matrix 521 may include openings that define color areas LA11, LA12, and LA13, respectively.

The first black matrix 521 may be made of any suitable material that can block light. In an embodiment, the first black matrix 521 may be made of a photosensitive composition, an organic material (e.g., organic substance), and/or a metallic material. In an embodiment, the photosensitive composition may include a binder resin, a polymerizable monomer, a polymerizable oligomer, a pigment, a dispersant, and the like. The metallic material may include chromium and the like.

The first color conversion filter is disposed on the second base substrate 601 and the first black matrix 521. The first color conversion filter may overlap the opening of the first black matrix 521.

In an embodiment, the first color conversion filter may be a color filter 540. Each of the color filters 540 may transmit only light of a specific color and block transmission of light of other colors by absorbing the light of the other colors. The light passing through each of the color filters 540 may display one of primary colors (e.g., three primary colors such as red, green, and blue). However, the display color of the light passing through each of the color filters 540 is not limited to the primary color, and may also be any one of cyan, magenta, yellow, and white.

In the current embodiment, the first color conversion filter may be a first color filter (e.g., a red first color filter) 541, a second color filter (e.g., a green second color filter) 542, and a third color filter (e.g., a blue third color filter) 543.

The first color filter 541 may be disposed in the first color area LA 11. The first color filter 541 may transmit light of the first color, but block light of the second color and light of the third color by absorbing the light of the second color and the light of the third color. Here, the first color may be red, the second color may be green, and the third color may be blue. For example, the first color filter 541 may be a red color filter and may include a red colorant. The red color filter may transmit red light but block green and blue light by absorbing the green and blue light.

The second color filter 542 may be disposed in the second color area LA 12. The second color filter 542 may transmit the light of the second color, but block the light of the first color and the light of the third color by absorbing the light of the first color and the light of the third color. For example, the second color filter 542 may be a green color filter and may include a green colorant. The green color filter may transmit green light but block red and blue light by absorbing the red and blue light.

The third color filter 543 may be disposed in the third color area LA 13. The third color filter 543 may transmit the light of the third color, but block the light of the first color and the light of the second color by absorbing the light of the first color and the light of the second color. For example, the third color filter 543 may be a blue color filter and may include a blue colorant. The blue color filter may transmit blue light but block red and green light by absorbing the red and green light.

Since the color filter 540 absorbs a considerable amount of external light, reflection of the external light can be reduced even without adding a polarizer or the like.

In an embodiment, a boundary portion between the color filters 540 may be located in the non-light emitting area NLA. That is, the boundary portion between the color filters 540 may overlap the first black matrix 521.

The first cap layer 511 is disposed on the first color conversion filter. The first capping layer 511 may prevent or substantially prevent impurities, such as moisture and/or air, from being introduced from the outside and damaging and/or contaminating the color filters, etc. In addition, the first capping layer 511 may prevent or substantially prevent the colorant contained in each color filter from diffusing to other elements.

In some embodiments, first cap layer 511 may be made of an inorganic material. For example, first cap layer 511 may comprise silicon nitride, aluminum nitride, zirconium nitride, titanium nitride, hafnium nitride, tantalum nitride, silicon oxide, aluminum oxide, titanium oxide, tin oxide, cerium oxide, and/or silicon oxynitride.

First cap layer 511 may be formed by sputtering, ALD, and/or CVD.

The second color conversion filter and the light transmission pattern 533 are disposed on the first cover layer 511. The second color conversion filter may be a wavelength conversion pattern 530. Each of the wavelength conversion patterns 530 may convert a peak wavelength of incident light into another (e.g., specific) peak wavelength and output light having the another (e.g., specific) peak wavelength. The light passing through each of the wavelength conversion patterns 530 may display one of primary colors (e.g., three primary colors such as red, green, and blue). However, the display color of the light passing through each of the wavelength conversion patterns 530 is not limited to the primary color, and may also be any one of cyan, magenta, yellow, and white.

In the current embodiment, the wavelength conversion pattern 530 includes a first wavelength conversion pattern 531 and a second wavelength conversion pattern 532 that are different from each other.

The first wavelength conversion pattern 531 may be disposed in the first color area LA 11. In an exemplary embodiment, the first wavelength conversion pattern 531 may convert blue light into red light in a range of about 610nm to about 650nm and output the red light. The first wavelength conversion pattern 531 may not be disposed in the second and third color areas LA12 and LA 13.

The first wavelength conversion pattern 531 may include a first matrix resin 5311 and a first wavelength conversion material 5313 dispersed in the first matrix resin 5311, and may further include a first scatterer 5315 dispersed in the first matrix resin 5311.

The first matrix resin 5311 may be any suitable material having high light transmittance and suitable (e.g., excellent) dispersion characteristics for the first wavelength converting material 5313 and the first scatterer 5315. For example, the first matrix resin 5311 may include an organic material such as an epoxy resin, an acrylic resin, a cardo resin, and/or an imide resin.

The first wavelength converting material 5313 may convert a peak wavelength of incident light to another (e.g., a specific) peak wavelength. Examples of the first wavelength converting material 5313 may include quantum dots, quantum rods, and phosphors. For example, a quantum dot may be a particulate material that emits light of a particular color when an electron transitions (e.g., moves) from a conduction band to a valence band.

The quantum dots may be semiconductor nanocrystal materials. Quantum dots can have a particular band gap depending on their composition and size. Accordingly, the quantum dots may absorb light and then emit light having a unique wavelength. Examples of semiconductor nanocrystals of quantum dots include group IV nanocrystals, group II-VI compound nanocrystals, group III-V compound nanocrystals, group IV-VI compound nanocrystals, and combinations thereof.

The group IV nanocrystals may be, but are not limited to, silicon (Si), germanium (Ge), and/or binary compounds such as silicon carbide (SiC) and/or silicon germanium (SiGe).

Further, the group II-VI compound nanocrystals can be, but are not limited to, binary compounds (such as CdSe, CdTe, ZnS, ZnSe, ZnTe, ZnO, HgS, HgSe, HgTe, MgSe, MgS, or combinations thereof), ternary compounds (such as CdSeS, CdSeTe, CdSTe, ZnSeS, ZnSeTe, ZnSTe, HgSeS, HgSeTe, HgSTe, CdZnSe, CdZnTe, CdHgS, CdHgSe, CdHgTe, HgZnSe, HgZnTe, MgZnSe, MgZnS, or combinations thereof), and/or quaternary compounds (such as HgZnTeS, CdZnSeS, CdZnSeTe, CdZnSTe, cdggses, CdHgSeTe, CdHgSTe, HgZnSeS, ZnSeTe, hghte, or combinations thereof).

Further, the III-V compound nanocrystals can be, but are not limited to, binary compounds (such as GaN, GaP, GaAs, GaSb, AlN, AlP, AlAs, AlSb, InN, InP, InAs, InSb, or combinations thereof), ternary compounds (such as GaNP, GaNAs, GaNSb, AlNP, alinsb, AlPAs, AlPSb, InP, InNP, InNAs, InP ps, InP sb, or combinations thereof), and/or quaternary compounds (such as GaAlNP, GaAlNAs, GaAlNSb, GaAlPAs, GaAlPSb, gainp, GaInNAs, gainsb, ingapas, GaInPSb, inalnnp, InAlNSb, inalnspa, InAlPAs, inalpab, or combinations thereof).

Group IV-VI compound nanocrystals can be, but are not limited to, binary compounds (such as SnS, SnSe, SnTe, PbS, PbSe, PbTe, or combinations thereof), ternary compounds (such as SnSeS, SnSeTe, SnSTe, PbSeS, PbSeTe, SnPbS, SnPbSe, SnPbTe, or combinations thereof), and/or quaternary compounds (such as SnPbSSe, SnPbSeTe, SnPbSTe, or combinations thereof).

The quantum dots may have a core-shell structure including a core including the nanocrystals described above and a shell surrounding the core. The shell of the quantum dot may be used as a protective layer for maintaining semiconductor characteristics by preventing or reducing chemical denaturation of the core, and/or as a charging layer for imparting electrophoretic characteristics to the quantum dot. The shell may be a single layer or multiple layers. Examples of the shell of the quantum dot include a metal oxide or a non-metal oxide, a semiconductor compound, and a combination thereof.

For example, the metal oxide or metalloid oxide can be, but is not limited to, a binary compound (such as SiO)₂、Al₂O₃、TiO₂、ZnO、MnO、Mn₂O₃、Mn₃O₄、CuO、FeO、Fe₂O₃、Fe₃O₄、CoO、Co₃O₄And/or NiO) and/or ternary compounds (such as MgAl)₂O₄、CoFe₂O₄、NiFe₂O₄And/or CoMn₂O₄)。

Further, the semiconductor compound may be, but is not limited to, CdS, CdSe, CdTe, ZnS, ZnSe, ZnTe, GaAs, GaP, GaSb, HgS, HgSe, HgTe, InAs, InP, InSb, AlAs, AlP, and/or AlSb.

The light emitted from the first wavelength converting material 5313 may have a Full Width Half Maximum (FWHM) of about 45nm or less, about 40nm or less, or about 30nm or less. Therefore, the color purity and color reproducibility of the display device can be improved. Further, light emitted from the first wavelength converting material 5313 can be radiated in various directions regardless of the incident direction of the incident light. Accordingly, lateral visibility of the display device can be improved.

A portion of the light L emitted from the organic light emitting diode 310 may be transmitted through the first wavelength conversion pattern 531 without being converted into red light by the first wavelength conversion material 5313. A component (e.g., a portion of the light L) incident on the first color filter 541 without being converted by the first wavelength conversion pattern 531 may be blocked by the first color filter 541. On the other hand, the red light output from the first wavelength conversion pattern 531 may be transmitted to the outside through the first color filter 541. Accordingly, the first light L1 output from the first color region LA11 may be red light.

The first diffuser 5315 may have a refractive index different from that of the first matrix resin 5311, and may form an optical interface with the first matrix resin 5311. For example, the first scatterer 5315 may be a light scattering particle. The first scatterer 5315 mayIs any suitable material that can scatter at least a portion of the transmitted light. For example, the first scatterer 5315 may be a metal oxide particle and/or an organic particle. Examples of the metal oxide include titanium oxide (TiO)₂) Zirconium oxide (ZrO)₂) Alumina (Al)₂O₃) Indium oxide (In)₂O₃) Zinc oxide (ZnO) and tin oxide (SnO)₂). Examples of the organic particulate material include acrylic resins and urethane resins. The first diffuser 5315 may scatter incident light in a random direction without substantially changing the wavelength of light transmitted through the first wavelength conversion pattern 531, regardless of the incident direction of the light. Accordingly, the first diffuser 5315 may increase the length of the path of light transmitted through the first wavelength conversion pattern 531 and increase the color conversion efficiency of the first wavelength conversion material 5313.

In some embodiments, the thickness of the first wavelength conversion pattern 531 may be 3 μm to 15 μm. The content (e.g., weight percentage) of the first wavelength converting material 5313 in the first wavelength converting pattern 531 may be 10% to 60%. Further, a content (e.g., weight percentage) of the first scatterer 5315 in the first wavelength conversion pattern 531 may be 2% to 15%.

The second wavelength conversion pattern 532 may be disposed in the second color area LA 12. In an exemplary embodiment, the second wavelength conversion pattern 532 may convert blue light into green light in a range of about 510nm to about 550nm and output the green light. The second wavelength conversion pattern 532 may not be disposed in the first and third color areas LA11 and LA 13.

The second wavelength conversion pattern 532 may include a second matrix resin 5321 and a second wavelength conversion material 5323 dispersed in the second matrix resin 5321, and may further include a second scatterer 5325 dispersed in the second matrix resin 5321.

The second matrix resin 5321 may be any suitable material having high light transmittance and suitable (e.g., excellent) dispersion characteristics for the second wavelength converting material 5323 and the second scatterer 5325. For example, the second matrix resin 5321 may include an organic material such as an epoxy resin, an acrylic resin, a cardo resin, and/or an imide resin.

Examples of the second wavelength converting material 5323 may include quantum dots, quantum rods, and phosphors. Other details of the second wavelength converting material 5323 are substantially the same as or similar to those of the first wavelength converting material 5313 described above, and thus a detailed description thereof is omitted.

The first wavelength converting material 5313 and the second wavelength converting material 5323 may both be composed of quantum dots. In this case, the diameter of the quantum dots constituting the first wavelength converting material 5313 may be larger than the diameter of the quantum dots constituting the second wavelength converting material 5323. For example, the quantum dot size of the first wavelength converting material 5313 may be aboutTo aboutFurther, the quantum dot size of the second wavelength converting material 5323 may be aboutTo about

The light passing through the first and second wavelength conversion patterns 531 and 532 may be in a non-polarized state by depolarization. As used herein, the term "unpolarized light" refers to light that is not composed of a polarization component only in a particular direction, i.e., light that is not polarized only in a particular direction. In other words, the term "unpolarized light" refers to light composed of randomly polarized components. An example of unpolarized light is natural light.

The second diffuser 5325 may have a refractive index different from that of the second matrix resin 5321, and may form an optical interface with the second matrix resin 5321. For example, the second scatterer 5325 may be a light scattering particle. Other details of the second diffuser 5325 are substantially the same as or similar to those of the first diffuser 5315 described above, and thus a detailed description thereof is omitted.

In some embodiments, the thickness of the second wavelength conversion pattern 532 may be 3 μm to 15 μm. The content (e.g., weight percentage) of the second wavelength converting material 5323 in the second wavelength converting pattern 532 may be 10% to 60%. Further, a content (e.g., weight percentage) of the second scatterer 5325 in the second wavelength conversion pattern 532 may be 2% to 15%.

The light L emitted from the organic light emitting diode 310 may be provided to the second wavelength conversion pattern 532, and the second wavelength conversion material 5323 may convert the light L emitted from the organic light emitting diode 310 into green light and output the green light.

A portion of the light L emitted from the organic light emitting diode 310 may be transmitted through the second wavelength conversion pattern 532 without being converted into green light by the second wavelength conversion material 5323, and may be blocked by the second color filter 542. On the other hand, among the emitted light L, green light output from the second wavelength conversion pattern 532 may be transmitted to the outside through the second color filter 542. Accordingly, the second light L2 output from the second color area LA12 may be green light.

The light-transmitting pattern 533 may be located in the third color region LA13, and may not be located in the first and second color regions LA11 and LA 12. The light-transmitting pattern 533 may transmit incident light substantially as it is.

The light-transmitting pattern 533 may include a third base resin 5331 and third scatterers 5335 dispersed in the third base resin 5331.

The third base resin 5331 may be made of an organic material having high light transmittance. The third base resin 5331 may be made of the same material as the first base resin 5311, or may include at least one of the materials mentioned as examples of the material of the first base resin 5311.

The third diffuser 5335 may have a refractive index different from that of the third matrix resin 5331, and may form an optical interface with the third matrix resin 5331. For example, the third scatterer 5335 may be a light scattering particle. The third scatterer 5335 can be any suitable scatterer capable of scattering at least a portion of the transmitted lightA material. For example, the third scatterer 5335 may be metal oxide particles and/or organic particles. Examples of the metal oxide include titanium oxide (TiO)₂) Zirconium oxide (ZrO)₂) Alumina (Al)₂O₃) Indium oxide (In)₂O₃) Zinc oxide (ZnO) and tin oxide (SnO)₂). Examples of the organic particulate material include acrylic resins and urethane resins. The third diffuser 5335 may scatter incident light in a random direction without substantially changing the wavelength of light transmitted through the light-transmitting pattern 533, regardless of the incident direction of the light. Accordingly, the third diffuser 5335 may improve lateral visibility of light transmitted through the light-transmitting pattern 533.

The light L emitted from the organic light emitting diode 310 is transmitted to the outside through the light transmission pattern 533 and the third color filter 543. That is, the third light L3 output from the third color region LA13 may have the same wavelength as that of the light L (e.g., blue light emitted from the organic light emitting diode 310).

The first wavelength conversion pattern 531, the second wavelength conversion pattern 532, and the light transmission pattern 533 may be spaced apart from each other in a plan view. Accordingly, the respective materials in the first wavelength conversion pattern 531, the second wavelength conversion pattern 532, and the light transmission pattern 533 are not mixed with each other. A space may be formed between the first wavelength conversion pattern 531, the second wavelength conversion pattern 532, and the light transmission pattern 533, which are spaced apart from each other.

The second cap layer 512 may be disposed on the first wavelength conversion pattern 531, the second wavelength conversion pattern 532, and the light transmission pattern 533. The second capping layer 512 may cover the first wavelength conversion pattern 531, the second wavelength conversion pattern 532, and the light transmission pattern 533. The second cover layer 512 may include (e.g., cover) spaces between the first wavelength conversion pattern 531, the second wavelength conversion pattern 532, and the light-transmitting pattern 533. In these spaces, second cap layer 512 may directly contact first cap layer 511.

The second cap layer 512 together with the first cap layer 511 may seal the first wavelength conversion pattern 531, the second wavelength conversion pattern 532, and the light transmission pattern 533, thereby preventing or substantially preventing foreign substances, such as moisture and/or air, from being introduced from the outside and damaging and/or contaminating the first wavelength conversion pattern 531, the second wavelength conversion pattern 532, and the light transmission pattern 533.

The second cap layer 512 may be made of an inorganic material (e.g., an inorganic substance). The second cap layer 512 may be made of the same material as that of the first cap layer 511, or may include at least one of the materials mentioned in the description of the first cap layer 511.

The thickness of the second cap layer 512 may be aboutOr smaller. The second cap layer 512 may be, but is not limited to, a single layer. Second cap layer 512 may be formed by the same method as that of first cap layer 511, or may be formed by one of the methods illustrated in connection with first cap layer 511.

The second capping layer 512 may include a material having a tenth refractive index. For example, the tenth refractive index may have a range of about 1.4 to about 2.0 for light of about 560 nm.

The second black matrix 522 is disposed on the second capping layer 512. The second black matrix 522 may be disposed along a boundary of each of the color areas LA11, LA12, and LA13, and may block transmission of light. The second black matrix 522 may overlap the pixel defining layer 330. The second black matrix 522 may overlap a space between the first wavelength conversion pattern 531, the second wavelength conversion pattern 532, and the light transmission pattern 533.

The second black matrix 522 may be made of any suitable material that can block light. The second black matrix 522 may be made of the same material as that of the first black matrix 521, or may include at least one of the materials mentioned in the description of the first black matrix 521.

The third capping layer 513 is disposed on the second capping layer 512 and the second black matrix 522. The third capping layer 513 may overlap the second capping layer 512 in the light emitting region, and may overlap the second black matrix 522 in the non-light emitting region NLA.

The third capping layer 513 may be made of an inorganic material (e.g., an inorganic substance). The third cap layer 513 may be made of the same material as that of the first cap layer 511, or may include at least one of the materials mentioned in the description of the first cap layer 511.

The thickness of the third cap layer 513 may be aboutOr smaller. The third capping layer 513 may be, but is not limited to, a single layer. The third cap layer 513 may be formed by the same method as that of the first cap layer 511, or may be formed by one of the methods exemplified in connection with the first cap layer 511.

The third capping layer 513 may include a material having an eleventh refractive index. For example, the eleventh refractive index may have a range of about 1.55 to about 1.65 for light of about 560 nm. In an embodiment, the third capping layer 513 may be omitted.

The filling layer 70 is located between the third cap layer 513 and the sixth sub-inorganic layer 433. The filling layer 70 may include a material having a twelfth refractive index. The twelfth refractive index may have a range of about 1.4 to about 1.6 for light of about 560 nm. In an embodiment, the twelfth refractive index may be lower than the eleventh refractive index and the ninth refractive index. In this case, the filling layer 70 may be made of a substantially sparser material than the third cap layer 513 and the sixth sub inorganic layer 433.

Fig. 6 is a sectional view of a modified example of the organic light emitting diode 310 shown in fig. 5. Fig. 7 is a sectional view of a modified example of the organic light emitting diode 310 shown in fig. 5.

Referring to fig. 6, the organic light emitting layer 320_1 included in the organic light emitting diode 310_1 may further include a first charge generation layer CGL11 on the first light emitting layer EL11 and a second light emitting layer EL12 on the first charge generation layer CGL11, and the first electron transport layer ETL1 may be on the second light emitting layer EL 12.

The first charge generation layer CGL11 may inject charges into each adjacent light emitting layer. The first charge generation layer CGL11 may adjust charge balance between the first light emitting layer EL11 and the second light emitting layer EL 12. In some embodiments, the first charge generation layer CGL11 may include an n-type charge generation layer and a p-type charge generation layer. The p-type charge generation layer may be disposed on the n-type charge generation layer.

Similar to the first light-emitting layer EL11, the second light-emitting layer EL12 may, but need not, emit blue light. The second light-emitting layer EL12 may emit blue light having a peak wavelength that is the same as or different from the peak wavelength of the blue light emitted from the first light-emitting layer EL 11. In an embodiment, the first and second light-emitting layers EL11 and EL12 may emit different colors of light. That is, when the first light-emitting layer EL11 emits blue light, the second light-emitting layer EL12 may emit green light.

Since the organic light emitting layer 320_1 configured as described above includes two light emitting layers, it may have better light emitting efficiency and a longer lifetime (e.g., service life) than the structure of fig. 5.

Fig. 7 shows that the organic light emitting layer 320_2 included in the organic light emitting diode 310_2 may include three light emitting layers EL11, EL12, and EL13 and two charge generation layers CGL11 and CGL12 interposed between the three light emitting layers EL11, EL12, and EL 13. Referring to fig. 7, the organic light emitting layer 320_2 may further include a first charge generation layer CGL11 on the first light emitting layer EL11, a second light emitting layer EL12 on the first charge generation layer CGL11, a second charge generation layer CGL12 on the second light emitting layer EL12, and a third light emitting layer EL13 on the second charge generation layer CGL 12. The first electron transport layer ETL1 may be positioned on the third light emitting layer EL 13.

The third light-emitting layer EL13 may emit blue light, similar to the first light-emitting layer EL11 and the second light-emitting layer EL 12. In an embodiment, each of the first, second, and third light-emitting layers EL11, EL12, and EL13 may emit blue light. Here, the peak wavelengths of blue light emitted from the first to third light-emitting layers EL11 to EL13 may be identical, or some of the peak wavelengths may be different. In an embodiment, the first, second, and third light-emitting layers EL11, EL12, and EL13 may emit different colors of light. For example, each light emitting layer may emit blue or green light. Alternatively, the light emitting layers may emit red light, green light, and blue light, respectively, to provide white light as a whole.

The path of light emitted from the organic light emitting diode 310 will now be described in more detail with reference to fig. 8 and 9.

Fig. 8 is a schematic cross-sectional view illustrating an optical path between the second interlayer insulating layer 350 and the second cap layer 512 in the embodiment of fig. 4. Fig. 9 is a schematic cross-sectional view showing an optical path in another OLED as a comparative example of fig. 8. Fig. 8 and 9 show cross sections of any one of the color regions (e.g., any one of the color regions). In fig. 8 and 9, the thickness of each element is exaggerated for ease of description.

Unlike the embodiment of fig. 8, the OLED of fig. 9 does not include the first sub inorganic layer 411, the third sub inorganic layer 413, the fourth sub inorganic layer 431, the sixth sub inorganic layer 433, and the third cap layer 513.

As described above, light emitted from the organic light emitting diode 310 of the first substrate 10 may travel toward the second substrate 30. In fig. 8 and 9, between the organic light emitting diode 310 and the second interlayer insulating layer 350, the emitting light L includes first emitting light La having an incident angle of 0 degree (θ a) and a refraction angle of 0 degree (θ a '), second emitting light Lb having an incident angle of a first angle θ b and a refraction angle of a second angle θ b ', and third emitting light Lc having an incident angle of a third angle θ c and a refraction angle of a fourth angle θ c '. Here, the first angle θ b, the second angle θ b ', the third angle θ c, and the fourth angle θ c' are acute angles. The third angle thetac is greater than the first angle thetab.

Referring to fig. 8, light La, Lb, and Lc emitted from the organic light emitting diode 310 of the OLED1 according to the current embodiment may sequentially pass through the second interlayer insulating layer 350, the first sub inorganic layer 411, the second sub inorganic layer 412, the third sub inorganic layer 413, the organic layer 420, the fourth sub inorganic layer 431, the fifth sub inorganic layer 432, the sixth sub inorganic layer 433, the filling layer 70, the third cap layer 513, and the second cap layer 512 to reach the second color conversion filter or light transmission pattern 533.

Referring to fig. 9, light La ', Lb ', and Lc ' emitted from the organic light emitting diode 310 of the OLED according to the comparative embodiment may sequentially pass through the second interlayer insulating layer 350, the second sub inorganic layer 412, the organic layer 420, the fifth sub inorganic layer 432, the filling layer 70, and the second cap layer 512 to reach the second color conversion filter or light transmission pattern 533.

First, the emitted lights La, Lb, and Lc of fig. 8 will be described in more detail.

The first light La may sequentially pass through a plurality of layers from the second interlayer insulating layer 350 to the second cap layer 512 without being refracted, and then reach the wavelength conversion pattern 530 or the light transmission pattern 533.

At the boundary surface between the second interlayer insulating layer 350 and the first and second sub inorganic layers 411 and 412, the angle of refraction of each of the second emitted light Lb and the third emitted light Lc may become larger than the angle of incidence, and the first and second sub inorganic layers 411 and 412 are sparse materials than the second interlayer insulating layer 350. At boundary surfaces between the first and second sub inorganic layers 411 and 412 and the third sub inorganic layer 413, a refraction angle of each of the second and third emitted lights Lb and Lc may become smaller than an incident angle, and the third sub inorganic layer 413 is a material denser than materials of the first and second sub inorganic layers 411 and 412. At the boundary surface between the third sub inorganic layer 413 and the organic layer 420, the angle of refraction of each of the second emitted light Lb and the third emitted light Lc may become larger than the angle of incidence, and the organic layer 420 is a material that is sparse than the material of the third sub inorganic layer 413. At the boundary surface between the organic layer 420 and the fourth and fifth sub inorganic layers 431 and 432, the refraction angle of each of the second and third emitted lights Lb and Lc may become smaller than the incident angle, and the fourth and fifth sub inorganic layers 431 and 432 are materials denser than the material of the organic layer 420. At the boundary surface between the fourth and fifth sub inorganic layers 431 and 432 and the sixth sub inorganic layer 433, the angle of refraction of each of the second emitted light Lb and the third emitted light Lc may become smaller than the angle of incidence, and the sixth sub inorganic layer 433 is a material denser than the material of the fourth and fifth sub inorganic layers 431 and 432. At the boundary surface between the sixth sub inorganic layer 433 and the filling layer 70, the angle of refraction of each of the second emitted light Lb and the third emitted light Lc may become larger than the angle of incidence, and the filling layer 70 is a material that is sparse than the material of the sixth sub inorganic layer 433. At the boundary surface between the filling layer 70 and the third and second cover layers 513 and 512, the angle of refraction of each of the second and third emitted lights Lb and Lc may become smaller than the angle of incidence, the third and second cover layers 513 and 512 being a material denser than the material of the filling layer 70. In this way, the second emitted light Lb and the third emitted light Lc may all reach the wavelength conversion pattern 530 or the light-transmitting pattern 533.

Next, the emitted lights La ', Lb ', and Lc ' of fig. 9 will be described.

As in the OLED1 of fig. 8, the second emitted light Lb' from the organic light emitting diode 310 of fig. 9 may reach the wavelength conversion pattern 530 or the light transmission pattern 533.

On the other hand, the third emitted light Lc' does not reach the wavelength conversion pattern 530 or the light-transmitting pattern 533. Since the third sub-inorganic layer 413 and the sixth sub-inorganic layer 433, which are relatively denser materials than the materials of the elements disposed under the third sub-inorganic layer 413 and the sixth sub-inorganic layer 433, are omitted from the OLED of fig. 9, a portion in which the refraction angle becomes smaller than the incident angle may be reduced as compared with the OLED1 of fig. 8. Accordingly, in emitting light, more (e.g., a larger portion) of the light L in the OLED of fig. 9 does not reach the wavelength conversion pattern 530 or the light transmission pattern 533 than the light L in the OLED1 of fig. 8.

The OLED1 can reduce light loss by providing a relatively dense material in the direction along which the emitted light L travels.

According to an embodiment of the present disclosure, a relationship between an interface refractive index difference (e.g., a refractive index difference between layers forming an interface) and an optical loss will now be described in more detail using the experimental examples of fig. 10 to 15.

Fig. 10 is a schematic cross-sectional view of a portion of an OLED according to a first experimental example. Fig. 11 is a schematic cross-sectional view of a portion of an OLED according to a second experimental example. Fig. 12 is a schematic cross-sectional view of a portion of an OLED according to a third experimental example. Fig. 13 is a schematic cross-sectional view of a portion of an OLED according to a fourth experimental example. Fig. 14 is a schematic cross-sectional view of a portion of an OLED according to a fifth experimental example. Fig. 15 is a schematic cross-sectional view of a portion of an OLED according to a sixth experimental example.

Referring to fig. 10 to 15, the OLED according to the experimental example is different from the OLED1 of fig. 4 in the configuration of encapsulation layers 400_1, 400_2, 400_3, 400_4, 400_5, and 400_ 6. Here, each of the encapsulation layers 400_1, 400_2, 400_3, 400_4, 400_5, and 400_6 is interposed between the second interlayer insulating layer 350 (or the organic light emitting diode 310) and the filling layer 70.

The encapsulation layer 400_1 of the first experimental example may have a structure in which the second sub inorganic layer 412 (e.g., 412_1), the third sub inorganic layer 413 (e.g., 413_1), the organic layer 420 (e.g., 420_1), and the fifth sub inorganic layer 432 (e.g., 432_1) are sequentially stacked.

The encapsulation layer 400_2 of the second experimental example may have a structure in which the second sub inorganic layer 412 (e.g., 412_2), the third sub inorganic layer 413 (e.g., 413_1), the organic layer 420 (e.g., 420_1), and the fifth sub inorganic layer 432 (e.g., 432_2) are sequentially stacked.

The encapsulation layer 400_3 of the third experimental example may have a structure in which the second sub inorganic layer 412 (e.g., 412_2), the third sub inorganic layer 413 (e.g., 413_1), the organic layer 420 (e.g., 420_1), the fifth sub inorganic layer 432 (e.g., 432_2), and the sixth sub inorganic layer 433 (e.g., 433_1) are sequentially stacked.

The encapsulation layer 400_4 of the fourth experimental example may have a structure in which the second sub inorganic layer 412 (e.g., 412_2), the third sub inorganic layer 413 (e.g., 413_2), the organic layer 420 (e.g., 420_1), the fifth sub inorganic layer 432 (e.g., 432_2), and the sixth sub inorganic layer 433 (e.g., 433_2) are sequentially stacked.

The encapsulation layer 400_5 of the fifth experimental example may have a structure in which the second sub inorganic layer 412 (e.g., 412_2), the third sub inorganic layer 413 (e.g., 413_3), the organic layer 420 (e.g., 420_1), the fifth sub inorganic layer 432 (e.g., 432_2), and the sixth sub inorganic layer 433 (e.g., 433_3) are sequentially stacked.

The encapsulation layer 400_6 of the sixth experimental example may have a structure in which the second sub inorganic layer 412 (e.g., 412_2), the third sub inorganic layer 413 (e.g., 413_1), the organic layer 420 (e.g., 420_1), and the fifth sub inorganic layer 432 (e.g., 432_3) are sequentially stacked. The thickness and refractive index of each element in each of the encapsulation layers 400_1, 400_2, 400_3, 400_4, 400_5, and 400_6 according to the first, second, third, fourth, fifth, and sixth experimental examples are as shown in table 1 below.

TABLE 1

The front light efficiency of the OLED of the first experimental example was reduced by about 6% compared to that of the OLED of the second experimental example. The front light efficiency of the OLED of the third experimental example was increased by about 4% as compared to that of the OLED of the second experimental example. The front light efficiency of the OLED of the fourth experimental example was increased by about 1% as compared to that of the OLED of the second experimental example. The front light efficiency of the OLED of the fifth experimental example was reduced by about 1% as compared to that of the OLED of the second experimental example. The front light efficiency of the OLED of the sixth experimental example was reduced by about 2% as compared to that of the OLED of the second experimental example.

By comparing the first and second experimental examples, it can be seen that the front light efficiency increases as the refractive index difference between the second and third sub inorganic layers 412 and 413 and the refractive index difference between the organic layer 420 and the fifth sub inorganic layer 432 decrease. In some embodiments, the refractive index difference between the second sub inorganic layer 412 and the third sub inorganic layer 413 may be 0.09 or less. Further, in some embodiments, the refractive index difference between the organic layer 420 and the fifth sub-inorganic layer 432 may be 0.14 or less.

By comparing the second and third experimental examples, it can be seen that as the difference in interfacial refractive index between the filling layer 70 and the encapsulation layer 400 decreases, the front light efficiency increases. Here, since the filling layer 70 is formed of a material that is sparse than that of the encapsulation layer 400, the third experimental example has a smaller interface refractive index difference between the filling layer 70 and the sixth sub inorganic layer 433_1, and the second experimental example has a larger interface refractive index difference between the filling layer 70 and the fifth sub inorganic layer 432_2, as compared to the second experimental example.

By comparing the third experimental example, the fourth experimental example, and the fifth experimental example, it can be seen that when the interface refractive indices are the same, a desired thickness (e.g., an optimal thickness) of each of the third sub inorganic layer 413 and the sixth sub inorganic layer 433 is about 0.1 μm. In some embodiments, the thickness of the third sub inorganic layer 413 and/or the sixth sub inorganic layer 433 may be about 0.1 μm.

Next, OLEDs according to additional embodiments will be described. The same elements as those described in conjunction with fig. 1 to 15 are denoted by the same reference numerals, and detailed description thereof will not be repeated.

Fig. 16 is a cross-sectional view of an OLED2 according to an embodiment.

Referring to fig. 16, the OLED2 according to the current embodiment is different from the OLED1 of fig. 4 in that the second black matrix 522 is omitted.

The second substrate 30 may include a second color conversion filter and a light-transmitting pattern 533 disposed on the first cover layer 511. The second and third cover layers 512 and 513 may be disposed on the second color conversion filter and light transmission pattern 533. The second and third cap layers 512 and 513 may be in direct contact with each other without an element interposed between the second and third cap layers 512 and 513.

Fig. 17 is a cross-sectional view of an OLED3 according to an embodiment.

Referring to fig. 17, the OLED3 according to the current embodiment is different from the OLED1 of fig. 4 in that the first and fourth sub inorganic layers 411 and 431 and the third cap layer 513 of the encapsulation layer 400 are omitted.

The encapsulation layer 400_7 may include a second sub inorganic layer 412 disposed on the second interlayer insulating layer 350, a third sub inorganic layer 413 disposed on the second sub inorganic layer 412, an organic layer 420 disposed on the third sub inorganic layer 413, a fifth sub inorganic layer 432 disposed on the organic layer 420, and a sixth sub inorganic layer 433 disposed on the fifth sub inorganic layer 432. The encapsulation layer 400_7 may be relatively thinner than the encapsulation layer 400 of the embodiment of fig. 4. Thus, the overall thickness of the OLED3 may be reduced.

The second black matrix 522 may be disposed on the second capping layer 512. The second substrate 30 and the filling layer 70 may contact each other, and a portion of the second capping layer 512 of the second substrate 30 and the second black matrix 522 may contact the filling layer 70. Unlike in the embodiment of fig. 4, the third cover layer 513 may be omitted, so that the total thickness of the OLED3 is relatively small.

Fig. 18 is a cross-sectional view of an OLED4 according to an embodiment.

Referring to fig. 18, the OLED4 according to the current embodiment is different from the OLED3 of fig. 17 in that it further includes a third cap layer 513.

In the second substrate 30, the second black matrix 522 may be disposed on the second cap layer 512, and the third cap layer 513 may be disposed on the second cap layer 512 and the second black matrix 522. The third capping layer 513 of the second substrate 30 may contact the filling layer 70.

According to an embodiment, the amount of light extracted at the front can be increased by adjusting the interfacial refractive index difference between the elements of the OLED. Accordingly, the luminance of the OLED may be improved.

In addition, the color conversion efficiency may be increased using the color conversion layer of the OLED according to the embodiment of the present disclosure.

However, the effects of the embodiments are not limited to those of the embodiments set forth herein. The above and other effects of the embodiments will become more apparent to those of ordinary skill in the art to which the embodiments belong by referring to the claims and their equivalents.

Expressions such as "at least one of … …" or "at least one selected from … …" modify an entire column of elements when it is behind the surface of the column, without modifying individual elements in the column. Furthermore, the use of "may" refer to "one or more embodiments of the invention" in describing embodiments of the invention. Additionally, the term "exemplary" is intended to mean an example or illustration.

As used herein, the terms "substantially," "about," and similar terms are used as terms of approximation rather than degrees, and are intended to account for inherent deviations in measured or calculated values that would be recognized by one of ordinary skill in the art. Moreover, any numerical range recited herein is intended to include all sub-ranges of equal numerical precision encompassed within the recited range. For example, a range of "1.0 to 10.0" is intended to include all sub-ranges between the recited minimum value of 1.0 and the recited maximum value of 10.0 (and including 1.0 and 10.0), i.e., having a minimum value equal to or greater than 1.0 and a maximum value equal to or less than 10.0 (such as, for example, 2.4 to 7.6). Any maximum numerical limitation recited herein is intended to include all lower numerical limitations subsumed therein, and any minimum numerical limitation recited herein is intended to include all higher numerical limitations subsumed therein. Accordingly, applicants reserve the right to modify this specification (including the claims) to specifically recite any sub-ranges subsumed within the ranges explicitly recited herein. All such ranges are intended to be inherently described in this specification as modified to specifically recite any such subrange.

Although the exemplary embodiments of the present disclosure have been described with reference to the accompanying drawings, it will be understood by those skilled in the art to which the present disclosure pertains that the subject matter of the present disclosure may be embodied in other (e.g., detailed) forms without changing the technical spirit and essential features of the present disclosure. The above-described exemplary embodiments of the present disclosure are, therefore, to be considered in all respects as illustrative and not restrictive.