CN106935621B - Substrate for organic light emitting display device and organic light emitting display device - Google Patents

Abstract

Provided are a substrate for an organic light emitting display device and an organic light emitting display device including: a protective layer having a non-planar shape; a first electrode on the protective layer, the first electrode having the non-planar shape; and a bank layer on the protective layer and the first electrode, the bank layer including an inclined opening for exposing the first electrode, the protective layer being formed at the opening of the bank layer and a portion of an area having the bank layer.

Description

Substrate for organic light emitting display device and organic light emitting display device

Cross Reference to Related Applications

The present application claims priority from korean patent application No.10-2015-0137259, 2015-9-30, korean patent application No.10-2015-0137750, 2016-4-2016-0053635, 2016 and 10-2016-0123377, 2016-9-26, which were filed by the korean intellectual property office, the disclosures of which are incorporated herein by reference.

Technical Field

The present disclosure relates to a substrate for an organic light emitting display device having improved light extraction efficiency and an organic light emitting display device.

Background

In recent years, an organic light emitting display device attracting attention as a display device has advantages of a fast response speed and large contrast ratio, light emitting efficiency, luminance, and viewing angle by using an Organic Light Emitting Diode (OLED) having a self-light emitting characteristic.

Light emitted from an organic light emitting layer of the organic light emitting display device is discharged to the outside of the organic light emitting display device through various components of the organic light emitting display device. However, among the light emitted from the organic light emitting layer, there is light that is not discharged to the outside of the organic light emitting display device but is blocked in the organic light emitting display device, and thus there is a problem in light extraction efficiency of the organic light emitting display device with respect to the front and the side of the organic light emitting display device.

Further, since the optical path length of light emitted from an organic light emitting element having a flat surface differs depending on the viewing angle, a color change occurs with respect to the viewing angle, and color shifts of red (R), green (G), and blue (B) increase, with the result that chromaticity characteristics are inferior in the lateral direction.

Therefore, a solution capable of solving this problem is required.

Disclosure of Invention

The substrate for forming the organic light emitting layer may include: a protective layer for planarizing a step due to formation of a transistor, an anode electrode formed on the protective layer, and a bank layer formed in a region other than a region for emitting light. Further, the organic light emitting layer is laminated on the flat anode electrode, and as a result, the organic light emitting layer is also formed in a flat form. Since the flat light emitting surface significantly depends on the optical path length for the viewing angle, a color change based on the viewing angle of the organic light emitting display device occurs, and as a result, it is characterized in that the flat light emitting surface has an influence on color shift on the side. Further, when a tilt angle is specified for the opening of the bank layer in the related art, some amount of light of the light emitting unit hits the tilted surface of the bank layer and is reflected on the tilted surface of the bank layer, and the amount of light collected in the front is also small.

Further, color shift occurring on the side of the organic light emitting display device refers to red color shift, green color shift, and blue color shift as well as white color shift with respect to the viewing angle, and since color shift occurring on the side increases on a flat light emitting surface, the color shift characteristic is inferior on the side. In this case, the color shift may represent a difference in color coordinates for a viewing angle.

An object achieved by the present disclosure is to provide a substrate for an organic light emitting display device and an organic light emitting display device, which can increase light extraction efficiency in front and side of the organic light emitting display device, reduce color shift for viewing angle, and improve intensity of lateral luminance of the organic light emitting display device.

Another object achieved by the present disclosure is to provide a substrate for an organic light emitting display device and an organic light emitting display device, which can reduce color shift for a viewing angle in a sub-pixel region.

Still another object achieved by the present disclosure is to provide an organic light emitting display device having an improved lifetime due to improved light extraction efficiency on the front and sides.

The object of the present disclosure is not limited to the foregoing object, and other objects not mentioned above will be apparent to those of ordinary skill in the art from the following description.

According to an aspect of the present disclosure, there is provided a substrate for an organic light emitting display device, including: a protective layer, a first electrode, and a bank layer. The protective layer has a non-planar shape. The first electrodes having the same non-planar shape are located on the protective layer. The bank layer is on the protective layer and the first electrode and includes an opening for exposing the first electrode. The protective layer is formed in the opening of the bank layer and under a portion of the bank layer.

According to another aspect of the present disclosure, there is provided an organic light emitting display device including: a bank layer, a protective layer, and an organic light emitting layer. The protective layer has a viewing angle improving structure. The organic light emitting display device includes a plurality of pixels and sub-pixels constituting the pixels. The bank layer exposes a light emitting region of the sub-pixel and includes a slanted opening. The organic light emitting layer is disposed on the protective layer including the viewing angle improvement structure, and the organic light emitting layer follows a form of the viewing angle improvement structure.

According to the present disclosure, there is provided a substrate for an organic light emitting display device, the substrate including a protective layer having a non-flat shape. Therefore, light extraction efficiency can be improved and color shift for viewing angle can be reduced.

Further, according to the present disclosure, there is provided a substrate for an organic light emitting display device, the substrate including a protective layer having a non-flat shape. Accordingly, since the optical path length can be maintained approximately equally for the viewing angle, the color shift for the viewing angle can be reduced and the intensity of the lateral luminance of the organic light emitting display device can be improved.

Further, according to the present disclosure, there is provided a substrate for an organic light emitting display device, the substrate including a bank layer having an inclined opening formed at a predetermined angle or more or an opening having a curved shape to improve light extraction efficiency on the front.

Further, according to the present disclosure, there is provided a substrate for an organic light emitting display device, the substrate having a non-flat shape on a protective layer formed in an opening of a bank layer and a region of the bank layer to suppress occurrence of deviation of the non-flat shape provided in a light emitting region and reduce color shift with respect to a viewing angle.

According to the present disclosure, there is provided a substrate for an organic light emitting display device, the substrate having a vertical length or a horizontal length of a plurality of light emitting regions different from each other to improve a lifetime of an organic light emitting element.

According to the present disclosure, there is provided an organic light emitting display device including a protective layer having a viewing angle improving structure to improve light extraction efficiency and reduce color shift for a viewing angle.

According to the present disclosure, there is provided an organic light emitting display device having a bank layer including an inclined opening for exposing a light emitting region of a sub-pixel or an opening having a curved shape to improve light efficiency on the front of the organic light emitting display device.

According to the present disclosure, there is provided an organic light emitting display device formed not to include a viewing angle improvement structure on a protective layer provided in at least one sub-pixel among a plurality of sub-pixels, in a pixel including the plurality of sub-pixels, to improve light efficiency on the front of the organic light emitting display device.

According to the present disclosure, there is provided an organic light emitting display device, in a pixel including a plurality of sub-pixels, wherein a protective layer of one sub-pixel among two or more sub-pixels includes a concave portion and a protective layer of another sub-pixel includes a convex portion, to reduce color shift with respect to a viewing angle.

According to the present disclosure, two or more openings of a bank layer are formed in one sub-pixel, and as a result, light emitted through a recess is reflected on a partition wall to improve light efficiency on the front of an organic light emitting display device.

The effects of the present disclosure are not limited to the foregoing effects, and various other effects are included in the present application.

Drawings

The above and other aspects, features and other advantages of the present disclosure will be more clearly understood from the following detailed description taken in conjunction with the accompanying drawings, in which:

fig. 1 is a cross-sectional view of an organic light emitting display device applied to an exemplary embodiment of the present disclosure;

fig. 2 is a plan view illustrating a light emitting region of an organic light emitting display device according to a first exemplary embodiment of the present disclosure;

FIG. 3 is a cross-sectional view of an organic light emitting display device taken along line A-B according to a first exemplary embodiment of the present disclosure;

fig. 4 is a view illustrating another form of a cross-sectional view of an organic light emitting display device taken along line a-B according to a first exemplary embodiment of the present disclosure;

fig. 5 is a plan view illustrating a light emitting region of an organic light emitting display device according to a second exemplary embodiment of the present disclosure;

FIG. 6 is a cross-sectional view of an organic light emitting display device taken along line C-D according to a second exemplary embodiment of the present disclosure;

fig. 7 is a plan view illustrating a light emitting region of an organic light emitting display device according to a third exemplary embodiment of the present disclosure;

fig. 8 is a plan view illustrating a light emitting region of an organic light emitting display device according to a fourth exemplary embodiment of the present disclosure;

fig. 9 is a plan view illustrating an arrangement structure of a plurality of recesses in a light emitting region of an organic light emitting display device according to the present disclosure;

fig. 10 is a plan view illustrating another shape in a light emitting region of an organic light emitting display device according to the present disclosure;

fig. 11 is a cross-sectional view of a portion of a light emitting region of an organic light emitting display device according to a fourth exemplary embodiment of the present disclosure, taken along line E-F;

fig. 12 is a plan view illustrating a light emitting region of an organic light emitting display device according to a fifth exemplary embodiment of the present disclosure;

fig. 13 is a plan view illustrating an organic light emitting display device including a plurality of recesses having different diameters for each light emitting region;

fig. 14 is a cross-sectional view of a light emitting region of the organic light emitting display device of fig. 13 taken along line G-H;

fig. 15 is a plan view illustrating a light emitting region of an organic light emitting display device according to a sixth exemplary embodiment of the present disclosure;

fig. 16 is a cross-sectional view of a light emitting region of an organic light emitting display device according to a sixth exemplary embodiment of the present disclosure;

fig. 17 is a plan view illustrating a light emitting region of an organic light emitting display device according to a seventh exemplary embodiment of the present disclosure;

fig. 18 is a cross-sectional view of a light emitting region of an organic light emitting display device taken along line K-L according to a seventh exemplary embodiment of the present disclosure;

fig. 19 is a plan view illustrating a light emitting region of an organic light emitting display device according to an exemplary embodiment extended based on a seventh exemplary embodiment of the present disclosure;

FIG. 20 is a cross-sectional view taken along line M-N of the plan view of FIG. 19;

fig. 21 is a plan view illustrating a light emitting region of an organic light emitting display device according to an eighth exemplary embodiment of the present disclosure;

fig. 22 and 23 are cross-sectional views of a light emitting region of an organic light emitting display device taken along line O-P according to an eighth exemplary embodiment of the present disclosure;

fig. 24 and 25 are cross-sectional views of a light emitting region of an organic light emitting display device taken along line O-P, as extended based on an eighth exemplary embodiment of the present disclosure;

fig. 26 is a plan view illustrating a light emitting region of an organic light emitting display device according to a ninth exemplary embodiment of the present disclosure;

fig. 27 and 28 are cross-sectional views of a light emitting region of an organic light emitting display device taken along the line Q-R according to a ninth exemplary embodiment of the present disclosure;

fig. 29 is a plan view illustrating a light emitting region of an organic light emitting display device according to a tenth exemplary embodiment of the present disclosure;

fig. 30 and 31 are cross-sectional views of a light emitting region of an organic light emitting display device taken along the line S-W according to a tenth exemplary embodiment of the present disclosure;

fig. 32 is a plan view illustrating one pixel of an organic light emitting display device according to an eleventh exemplary embodiment of the present disclosure;

fig. 33 is a plan view illustrating one pixel of an organic light emitting display device according to an exemplary embodiment extended based on an eleventh exemplary embodiment of the present disclosure;

fig. 34 is a sectional view taken along line T-U of the plan view of fig. 33.

Fig. 35A to 35D are diagrams illustrating color coordinates of white light according to viewing angles in a right direction, an upper direction, a left direction, and a lower direction from the center of an organic light emitting display device as a comparative example;

fig. 36A to 36D are diagrams illustrating color coordinates of white light according to viewing angles in a right direction, an upper direction, a left direction, and a lower direction from the center of an organic light emitting display device as an embodiment.

Detailed Description

Hereinafter, exemplary embodiments of the present disclosure will be described with reference to the accompanying drawings. The exemplary embodiments described below are provided as examples so that this disclosure will fully convey the spirit of the disclosure to those skilled in the art. As those skilled in the art will realize, the described embodiments may be modified in various different ways, all without departing from the spirit or scope of the present disclosure. Further, in the drawings, the size and thickness of the apparatus are exaggerated for ease of description. Like reference numerals refer to like elements throughout.

Shapes, sizes, proportions, angles, numbers, and the like shown in the drawings for describing the embodiments of the present disclosure are merely examples, and the present disclosure is not limited thereto. Like reference numerals generally refer to like elements throughout. Furthermore, in the following description, a detailed explanation of known related art may be omitted to avoid unnecessarily obscuring the subject matter of the present disclosure. Terms such as "comprising," "having," and "consisting of … …" as used herein are generally intended to allow for the addition of other components unless the term "only" is used. Any reference to singular may include plural unless explicitly stated otherwise.

Components are to be construed as including common error ranges even if not explicitly stated.

When terms such as "on … …," "above … …," "below … …," "after … …," and the like are used to describe a positional relationship between two parts, one or more parts may be disposed between the two parts unless these terms use the terms "immediately" or "directly".

Although the terms "first," "second," etc. are used to describe various components, these components are not limited by these terms. These terms are only used to distinguish one component from another component. Therefore, within the technical idea of the present disclosure, the first component mentioned below may be the second component.

As is well understood by those of ordinary skill in the art, the features of the various embodiments of the present disclosure can be combined or combined with each other, in part or in whole, and can be interconnected and operated in various technical ways, and the embodiments can be implemented independently or in relation to each other.

Fig. 1 is a sectional view of an organic light emitting display device applied to an exemplary embodiment of the present disclosure. Referring to fig. 1, an organic light emitting display device applied to an exemplary embodiment of the present disclosure includes a thin film transistor Tr and an organic light emitting element EL electrically connected to the thin film transistor Tr.

The thin film transistor Tr includes a gate electrode 121a, an active layer 122a, a source electrode 124a, and a drain electrode 123 a. Also, the organic light emitting element EL includes a first electrode 140a, an organic light emitting layer 150a, and a second electrode 160 a.

Specifically, the gate electrode 121a and the first insulating layer 110a of the thin film transistor Tr are disposed on the first substrate 100 a. An active layer 122a overlapping the gate electrode 121a is disposed on the first insulating layer 110a, and an etch stopper 132a for protecting a channel region of the active layer 122a is disposed on the active layer 122 a. The etch stop layer may also be omitted.

Also, a source electrode 124a and a drain electrode 123a contacting the active layer 122a are disposed on the active layer 122a, and a second insulating layer 120a is disposed on the source electrode 124a and the drain electrode 123 a. The drain electrode 123a is illustrated as being connected to the first electrode 140a through the contact hole of the second insulating layer 120a, but the organic light emitting display device applicable to the exemplary embodiment of the present disclosure is not limited to fig. 1. The source electrode 124a and the first electrode 140a may be connected to each other, and may further include a buffer layer disposed between the first substrate 100a and the active layer 122 a. Further, the type of the thin film transistor Tr applicable to the organic light emitting display device may also apply a coplanar structure, etc., in addition to the staggered structure of fig. 1.

In addition, a protective layer 130a is disposed on the second insulating layer 120 a. Meanwhile, an organic layer is interposed between two reflective layers, and an optical waveguide mode composed of a surface plasmon component generated at an interface between a metal and an organic layer occupies about 60% to 70% of emitted light. Therefore, a phenomenon in which 60% to 70% of light is not emitted but blocked in the organic light emitting layer 150a occurs, and it is necessary to extract light generated from the organic light emitting layer 150a to the outside of the display device.

To solve this problem, the protective layer 130a of the organic light emitting display device according to the exemplary embodiment of the present disclosure may have a non-flat shape implemented to reduce color shift for a viewing angle. That is, the protective layer 130a may include a viewing angle improving structure, and the protective layer 130a may be implemented, for example, by forming a plurality of concave portions 131a disposed at regular intervals. The plurality of concave portions 131a may have a hemispherical shape, a semi-ellipsoidal shape, or a semi-polyhedral shape, but is not limited thereto, and may be any shape for forming a non-flat upper surface.

A plurality of concave portions 131a may be disposed at positions corresponding to the light emitting region of each sub-pixel. Here, the light emitting region refers to a region in which the organic light emitting layer 150a emits light through the first electrode 140a and the second electrode 160 a. In addition, the light emitting region may refer to a region in which the first electrode 140a is exposed by the opening 136b of the bank layer 136a disposed on the first electrode 140a, but in a region where the first electrode 140a is formed, the light emitting region may include a region in which the organic light emitting layer 150a is formed on the bank layer 136a to emit light.

The plurality of recesses 131a are provided at positions corresponding to the light emitting region of each sub-pixel to increase the effect of extracting light emitted from the organic light emitting element EL to the outside of the display device. That is, the protective layer 130a having a non-flat shape is included to improve light extraction efficiency and reduce color shift for viewing angles. Further, since the optical path lengths for viewing angles can be kept substantially equal, color shift for viewing angles can be reduced and the intensity of lateral luminance can be improved.

On the protective layer 130a, a first electrode 140a of the organic light emitting element EL connected to the drain electrode 123a of the thin film transistor Tr is provided. In addition, in order to improve the light extraction capability of the organic light emitting layer 150a, a reflective layer may be further disposed under the first electrode 140 a.

A bank layer 136a is disposed on the protective layer 130a to expose a portion of an upper surface of the first electrode 140a, and an organic emission layer 150a may be disposed on the upper surface of the first electrode 140a exposed by the bank layer 136a and on the bank layer 136 a.

That is, the bank layer 136a is disposed on the protective layer 130a and the first electrode 140a and includes an opening 136b exposing the first electrode 140 a. The bank layer 136a serves to divide adjacent pixel (or sub-pixel) regions and may be disposed between the adjacent pixel (or sub-pixel) regions. The recess 131a of the protective layer 130a may be disposed to overlap the opening 136b of the bank layer 136 a. As described above, since the recess 131a of the overcoat layer 130a is disposed to overlap the color filter layer, the recess 131a of the overcoat layer 130a may overlap the opening 136b of the bank layer 136a and the color filter layer in the case of a top emission type organic light emitting display device. In the case of a bottom emission type organic light emitting display device, the recess 131a of the overcoat layer 130a overlaps the opening 136b of the bank layer 136a and may overlap a color filter layer disposed on the second insulating layer 120 a.

Among them, the organic emission layer 150a may be disposed only on the upper surface of the first electrode 140a exposed by the bank layer 136a, or on the first electrode 140a up to a portion of the top surface of the bank layer 136 a. Further, the second electrode 160a of the organic light emitting element EL is disposed to overlap the organic light emitting layer 150a and the bank layer 136 a.

Further, an encapsulation layer 170a for protecting the organic light emitting element EL from moisture and oxygen is disposed on the second electrode 160 a. In fig. 1, the encapsulation layer 170a is illustrated as a single-layer configuration, but exemplary embodiments of the present disclosure are not limited thereto, and the encapsulation layer 170a may also be formed of multiple layers. The second substrate 200a may be disposed on the encapsulation layer 170 a.

In addition, a polarizing plate may be disposed on the bottom surface of the first substrate 100 a. The polarizing plate may be a polarizing plate having a polarizing axis in a predetermined direction, and configured to transmit only light having the same optical axis as the polarizing axis direction among light incident from the bottom of the first substrate 100 a. In addition, the polarizing plate has a feature of having a polarizing axis in a predetermined direction, but the exemplary embodiments of the present disclosure are not limited thereto, and the polarizing plate may include a configuration further including a phase retardation film. In addition, the polarizing plate may be composed of a single layer or multiple layers.

In addition, fig. 1 illustrates a top emission type organic light emitting display device, but the exemplary embodiment of the present disclosure may be applied to a bottom emission type organic light emitting display device or a bidirectional emission type organic light emitting display device.

Meanwhile, when the exemplary embodiment of the present disclosure is applied to a bottom emission type organic light emitting display device, a color filter layer may be disposed on the second insulating layer 120 a. In this case, the color filter layer may be disposed in each of the plurality of sub-pixels or only some of the plurality of sub-pixels.

Meanwhile, the color filter layer may be disposed at a position corresponding to the light emitting region of each sub-pixel. Here, the light emitting region refers to a region in which the organic light emitting layer 150a emits light through the first electrode 140a and the second electrode 160a, and the formation of the color filter layer at a position corresponding to the light emitting region means that the color filter layer is disposed to prevent light emitted in adjacent light emitting regions from being mixed with each other.

In the above-described organic light emitting display device, in order to reduce color shift with respect to a viewing angle, the protective layer 130a having the concave portions 131a provided at regular intervals may be configured.

In this case, among the light incident to the interface between the recess 131a and the first electrode 140a of the organic light emitting element, the light incident at an incident angle of a total reflection critical angle or less is reflected on the reflective layer to be extracted as it is to the outside of the second substrate 200 a. Further, light incident at an incident angle of the critical angle of total reflection or more is not blocked in the organic light emitting element EL but collides with the concave portion 131a, and thus the optical path length varies. Finally, the propagation angle of the light is smaller than the total reflection critical angle, and thus the light is extracted to the outside of the second substrate 200 a. That is, light incident at an incident angle of a total reflection critical angle or more when the protective layer 130a is flat so as not to be extracted to the outside may be extracted to the outside through the concave portion 131a in the protective layer 130a, thereby improving light extraction efficiency of the organic light emitting display device. In addition, a reflective layer is formed under the first electrode 140a to more improve the light extraction efficiency of the organic light emitting display device.

Further, the pixel P includes one or more sub-pixels SP. The sub-pixel refers to a cell in which a specific kind of color filter layer is formed, or a cell in which a color filter layer is not formed but an organic light emitting element can emit light having a specific color. The colors defined in the sub-pixels may include red R, green G, and blue B, and may selectively include white W, but the present disclosure is not limited thereto.

However, for convenience of description, exemplary embodiments to be described below will be described in a configuration in which one pixel includes three sub-pixels. However, the present disclosure is not limited thereto, and one pixel may also include four sub-pixels including white.

In addition, an electrode connected to a thin film transistor for controlling light emission in each sub-pixel region of the display panel is referred to as a first electrode, and an electrode disposed on the front of the organic light emitting display device or disposed to include two or more pixel regions is referred to as a second electrode. When the first electrode is an anode electrode, the second electrode is a cathode electrode, and the reverse is also possible. Hereinafter, an example in which an anode electrode is used as the first electrode and an example in which a cathode electrode is used as the second electrode will be mainly described, but the present disclosure is not limited thereto.

Further, in the foregoing sub-pixel region, a color filter layer having a single color is provided or not provided. In addition, a light scattering layer may be disposed in each sub-pixel region in order to improve light extraction efficiency of the organic light emitting layer. The light scattering layer may be referred to as a viewing angle improving structure or a protective layer having a non-flat shape, and may be referred to as a microlens array, a nano pattern, a diffusion pattern, and silicon beads.

Hereinafter, as an example of the light scattering layer, a protective layer having a concave or convex portion or a plurality of concave and convex portions as a kind of microlens array will be mainly described, but exemplary embodiments according to the present disclosure are not limited thereto, and various structures for scattering light may be combined.

An exemplary embodiment of an organic light emitting display device applicable to the foregoing organic light emitting display device will be described below.

Fig. 2 is a plan view illustrating a light emitting region of an organic light emitting display device according to a first exemplary embodiment of the present disclosure.

Referring to fig. 2, the organic light emitting display device according to the first exemplary embodiment of the present disclosure includes a first sub-pixel SP11, a second sub-pixel SP12, and a third sub-pixel SP 13.

In this case, the second sub-pixel SP12 and the third sub-pixel SP13 may be disposed side by side with the first sub-pixel SP11 in the horizontal direction. The second sub-pixel SP12 and the third sub-pixel SP13 may be disposed side by side in the vertical direction.

The first, second, and third sub-pixels SP11, SP12, and SP13 may include light emitting regions emitting different colors, respectively. For example, the first light emitting region EA11 of the first sub-pixel SP11 may emit light of blue color B, the second light emitting region EA12 of the second sub-pixel SP12 may emit light of green color G, and the third light emitting region EA13 of the third sub-pixel SP13 may emit light of red color R.

The spectra of light emitted from these light emitting regions (spectra corresponding to red, green, and blue colors) are merely examples, and the spectra of light generated by the light emitting regions EA11, EA12, and EA13 of the first to third sub-pixels SP11, SP12, and SP13 may be various.

Also, a vertical length L11 of the first light emitting area EA11 may be greater than a vertical length L12 of the second light emitting area EA12 and a vertical length L13 of the third light emitting area EA 13. In addition, a vertical length L13 of the third light emitting area EA13 may be equal to or greater than a vertical length L12 of the second light emitting area EA 12.

Further, the horizontal length W11 of the first light emitting region EA11 may be less than the horizontal length W12 of the second light emitting region EA12 and the horizontal length W13 of the third light emitting region EA 13. A horizontal length W12 of the second light emitting area EA12 may be equal to or greater than a horizontal length W13 of the third light emitting area EA 13.

As such, the area of the light emitting region of each sub-pixel can be adjusted by adjusting the horizontal length and the vertical length of the light emitting region of each sub-pixel. For example, as shown in fig. 2, the area of the first light emitting area EA11 of the first sub-pixel SP11 may be larger than the area of the second light emitting area EA12 of the second sub-pixel SP12 and the area of the third light emitting area EA13 of the third sub-pixel SP 13.

In addition, areas of the second and third light emitting areas EA12 and EA13 may be equal to each other. However, when the vertical length L13 or the horizontal length W13 of the third light emitting area EA13 is greater than the vertical length L12 or the horizontal length W12 of the second light emitting area EA12, the area of the third light emitting area EA13 may be greater than that of the second light emitting area EA 12.

As a result, when the efficiency or lifetime of the organic light emitting element provided in each sub-pixel is low or short, the efficiency or lifetime of the organic light emitting element can be compensated by adjusting the area of the light emitting region. That is, as described above, the area of the light emitting region decreases in the order of the first sub-pixel SP11, the third sub-pixel SP13, and the second sub-pixel SP 12. In this case, the first sub-pixel SP11, the third sub-pixel SP13, and the second sub-pixel SP12 may be disposed to emit blue light, green light, and red light, respectively, according to the efficiency of the organic light emitting element, but the present disclosure is not limited thereto.

Accordingly, the vertical length or the horizontal length of the plurality of light emitting regions is differently formed, thereby improving the life of the organic light emitting element.

Also, the first, second, and third light emitting regions EA11, EA12, and EA13 may include a plurality of recesses 131. The recesses 131 are spaced apart from the other recesses 131 at regular intervals. Further, the plurality of recesses 131 may have a circular shape on a plane, but exemplary embodiments of the present disclosure are not limited thereto, and may have a polygonal shape such as an ellipse or a hexagon.

The diameters D of the plurality of concave portions 131 provided in the first light-emitting region EA11, the second light-emitting region EA12, and the third light-emitting region EA13 may be substantially the same as each other. As a result, light emitted from each of the light emitting regions EA11, EA12, and EA13 may be extracted to the outside of the organic light emitting display device with substantially the same efficiency. Also, the diameters D of the plurality of recesses 131 provided in each of the first, second, and third sub-pixels SP11, SP12, and SP13 of the organic light emitting display device according to the present disclosure are not limited thereto, and may be different from one another.

This structure will be described in detail below with reference to fig. 3.

Fig. 3 is a cross-sectional view of an organic light emitting display device according to a first exemplary embodiment of the present disclosure, taken along line a-B.

Referring to fig. 3, in a light emitting region of an organic light emitting display device according to a first exemplary embodiment of the present disclosure, a plurality of insulating layers 110 and 120 and a protective layer 130 having a plurality of recesses 131 are disposed on a substrate 100, and an organic light emitting element EL is disposed on the protective layer 130. Such a configuration may be applied to all of the first light emitting area EA11, the second light emitting area EA12, and the third light emitting area EA 13.

On the protective layer 130 having the plurality of concave portions 131, a reflective layer 141 may be disposed, and on the reflective layer 141, a first electrode 140, an organic light emitting layer 150, and a second electrode 160 of the organic light emitting element EL may be sequentially disposed. In this case, the shapes of the reflective layer 141, the first electrode 140, the organic emission layer 150, and the second electrode 160 may correspond to the shape of the recess 131 formed on the protective layer 130.

The organic light emitting layer 150 may have a small thickness in a region corresponding to the inclined surface of the recess 131. Specifically, the organic light emitting layer 150 is formed by a deposition method having linearity, and thus the thickness of the organic light emitting layer 150 in a direction perpendicular to the inclined surface of the recess 131 may be less than the thickness of the organic light emitting layer 150 formed in the remaining region except the inclined surface of the recess 131. The thickness of the organic light emitting layer 150 on the inclined surface of the recess 131 is small, and thus the current density on the inclined surface of the recess 131 is higher than other regions, thereby improving the light emitting efficiency of the organic light emitting element EL. Therefore, the organic light emitting element EL emits light mainly in the region corresponding to the inclined surface of the concave portion 131.

Further, in the region corresponding to the inclined surface of the concave portion 131, the incident angle of the light incident to the inclined surface of the concave portion 131 is mainly concentrated on the total reflection critical angle to enable multiple reflection and improve the light extraction efficiency.

In detail, a portion of light emitted from the organic light emitting layer 150 of the organic light emitting element EL is emitted in the direction of the second electrode 160 of the organic light emitting element EL to be emitted to the outside of the organic light emitting display apparatus. A part of the remaining light is emitted in the direction of the first electrode 140 of the organic light emitting element EL.

The refractive index of the organic light emitting layer 150 is substantially the same as the refractive index of the first electrode 140. Therefore, light emitted from the organic light emitting layer 150 passes through the first electrode 140, without changing an optical path at an interface between the organic light emitting layer 150 and the first electrode 140.

Among the light passing through the first electrode 140, the light reaching the reflective layer 141 at an incident angle less than a critical angle for total reflection hits the reflective layer 141, and the light path is changed into the direction of the second electrode 160, so that the light is emitted to the outside of the organic light emitting display device.

And, light reaching the reflective layer 141 at an incident angle greater than a critical angle for total reflection is totally reflected at an interface between the first electrode 140 and the reflective layer 141. The totally reflected light collides at least twice with the reflective layer 141 having the same form as the concave portion 131 formed on the protective layer 130, and may finally become light oriented at an incident angle smaller than the critical angle for total reflection.

Therefore, due to the recesses 131 formed in the first, second, and third light emitting regions EA11, EA12, and EA13, light directed at an incident angle greater than the critical angle for total reflection is not blocked in the organic light emitting element EL but extracted to the outside of the organic light emitting display device, thereby improving light efficiency.

Specifically, on a flat light emitting surface, there are the following problems: the optical path length varies greatly with respect to the viewing angle, and thus color shift with respect to the viewing angle is generated. However, in the organic light emitting display device according to the first exemplary embodiment of the present disclosure, each of the light emitting regions EA11, EA12, and EA13 has a plurality of concave portions 131, thereby improving color shift for a viewing angle on a side of the organic light emitting display device. The optical path length for the viewing angle can be kept substantially equal, thereby improving the color shift for the viewing angle and increasing the intensity of the lateral luminance of the organic light emitting display device.

In other words, among the light passing through the first electrode 140, most of the light reaching the reflective layer 141 at an incident angle smaller than a critical angle for total reflection may be emitted in a front direction. Also, among the light passing through the first electrode 140, most of the light reaching the reflective layer 141 at an incident angle greater than a critical angle of total reflection may be emitted in a lateral direction.

That is, due to the viewing angle improving structure composed of the plurality of concave portions 131, light may also be spread in the side direction of each of the light emitting regions EA11, EA12, and EA13, thereby improving the side light extraction efficiency.

Also, gaps G1 between the recesses 131 formed on the protective layer 130 and other adjacent recesses 131 may be identical to each other, the gap G1 having a predetermined length. However, the gap G1 between the recess 131 and the other adjacent recesses 131 is not limited to the first exemplary embodiment of the present disclosure, and may be formed as shown in fig. 4.

Fig. 4 is a diagram illustrating another form of the gap G1 between a recess and other adjacent recesses of the present disclosure.

Referring to fig. 4, the plurality of recesses 131 formed on the protective layer 130 are not spaced apart from each other but are provided to be connected to each other.

That is, the gap between the recess 131 and another adjacent recess 131 may be 0 (zero), and the reflective layer 141 and the organic light emitting element EL may be formed according to the shape of the plurality of recesses 131 formed on the protective layer 130.

The shape of the concave portion 131 shown in fig. 2 is not limited to the foregoing exemplary embodiment, and it may be formed as shown in fig. 5 and 6.

Fig. 5 is a plan view illustrating a light emitting region of an organic light emitting display device according to a second exemplary embodiment of the present disclosure, and fig. 6 is a cross-sectional view of the organic light emitting display device according to the second exemplary embodiment of the present disclosure, taken along line C-D. The organic light emitting display device according to the second exemplary embodiment of the present disclosure may include the same components as those of the above-described exemplary embodiments. Descriptions overlapping with the above exemplary embodiment may be omitted or simplified below. In addition, like components have like reference numerals.

In fig. 5, the difference is that a plurality of concave portions in the plan view of fig. 2 are formed by a plurality of convex portions 231. That is, in each of the first, second, and third light emitting regions EA21, EA22, and EA23 of the organic light emitting display device according to the second exemplary embodiment, the plurality of convex parts 231 may be adjacent to each other at regular intervals.

Referring to fig. 6, an exemplary embodiment having a plurality of protrusions 231 will be described in detail. In fig. 6, a plurality of convex portions 231 formed on the protective layer 130 are disposed at regular intervals.

As a result, the reflective layer 241 and the first electrode 240, the organic light emitting layer 250, and the second electrode 260 of the organic light emitting element EL disposed on the protective layer 130 may also be formed to have a plurality of convex portions according to the shape of the protective layer 130. In this way, the organic light emitting display device includes the protective layer 130 having the plurality of convex portions 231 and the organic light emitting element EL in the first light emitting region EA21, the second light emitting region EA22, and the third light emitting region EA23, thereby minimizing color shift with respect to a viewing angle.

Further, the shape of the convex portion is not limited to the foregoing exemplary embodiment, and it may be formed as shown in fig. 7.

Fig. 7 is a plan view illustrating a light emitting region of an organic light emitting display device according to a third exemplary embodiment of the present disclosure. The organic light emitting display device according to the third exemplary embodiment of the present disclosure may include the same constituent elements as those of the foregoing exemplary embodiments. Descriptions overlapping with the foregoing exemplary embodiment may be omitted or simplified below. In addition, like components have like reference numerals.

Referring to fig. 7, the organic light emitting display device according to the third exemplary embodiment of the present disclosure includes a first sub-pixel SP11, a second sub-pixel SP32, and a third sub-pixel SP 33. The first sub-pixel SP11 includes a first light emitting area EA11, the second sub-pixel SP32 includes a second light emitting area EA32, and the third sub-pixel SP33 includes a third light emitting area EA 33.

Also, a vertical length L11 of the first light emitting area EA11 may be equal to a vertical length L22 of the second light emitting area EA32 and a vertical length L23 of the third light emitting area EA 33. Further, a horizontal length W21 of the first light emitting region EA11 is greater than a horizontal length W23 of the third light emitting region EA33, and a horizontal length W23 of the third light emitting region EA33 may be greater than a horizontal length W22 of the second light emitting region EA 32.

Therefore, the light emitting area of the first light emitting area EA11 may be larger than that of the third light emitting area EA33 and the light emitting area of the third light emitting area EA33 may be larger than that of the second light emitting area EA 32. As a result, organic light emitting elements that emit light of different colors may be disposed in the first light emitting region EA11, the second light emitting region EA32, and the third light emitting region EA33 in consideration of efficiency and life of the organic light emitting elements. That is, as described above, the area of the light emitting region may decrease in the order of the first light emitting region EA11, the third light emitting region EA33, and the second light emitting region EA 32. In this case, the first light emitting region EA11, the third light emitting region EA33, and the second light emitting region EA32 may be disposed to emit blue light, green light, and red light, respectively, according to the efficiency or lifetime of the organic light emitting element, but the present disclosure is not limited thereto.

Accordingly, the horizontal lengths of the plurality of light emitting regions are differently formed, thereby improving the efficiency or lifetime of the organic light emitting element.

Next, an organic light emitting display device according to a fourth exemplary embodiment of the present disclosure will be described below.

Fig. 8 is a plan view illustrating a light emitting region of an organic light emitting display device according to a fourth exemplary embodiment of the present disclosure. An organic light emitting display device according to a fourth exemplary embodiment of the present disclosure may include the same components as those of the above-described exemplary embodiments. Descriptions overlapping with the foregoing exemplary embodiment may be omitted or simplified below. In addition, like components have like reference numerals.

Referring to fig. 8, an organic light emitting display device according to a fourth exemplary embodiment of the present disclosure includes a plurality of sub-pixels SP41 and SP42, and each sub-pixel includes a light emitting region. In fig. 8, only two subpixels applicable to the organic light emitting display device are illustrated, but the two subpixels illustrated in fig. 8 are applicable to all organic light emitting display devices having a pixel composed of two or more subpixels.

Therefore, the organic light emitting display device according to the fourth exemplary embodiment of the present disclosure includes a first sub-pixel SP41 and a second pixel SP42, the first sub-pixel SP41 including a first light emitting area EA41, and the second pixel SP42 including a second light emitting area EA 42. In this case, the first and second light emitting regions EA41 and EA42 may emit different colors of light.

The first light-emitting region EA41 includes a plurality of first concave portions 131. In this case, the plurality of first recesses 131 may be continuously disposed at regular intervals in the vertical direction and the horizontal direction on a plane. In this case, the distance between the adjacent recesses 131 corresponds to S1 in the drawing.

Further, the second light emitting area EA42 includes a plurality of second recesses 331, and the plurality of second recesses 331 may also be arranged in a row at regular intervals in the vertical and horizontal directions.

The plurality of first concave portions 131 and the plurality of second concave portions 331 are disposed at regular intervals in the vertical direction and the horizontal direction, thereby reducing color shift for a viewing angle on a side of the organic light emitting display device by the plurality of first concave portions 131 and the plurality of second concave portions 331.

Also, the arrangement of the first and second recesses 131 and 331 of the organic light emitting display device according to the fourth exemplary embodiment is not limited thereto, and the first and second recesses 131 and 331 may be provided as shown in fig. 9.

Fig. 9 is a plan view illustrating an arrangement structure of a plurality of recesses in a light emitting region of an organic light emitting display device.

Referring to fig. 9, the plurality of recesses 131 provided in the first light emitting region EA51 and the plurality of recesses 331 provided in the second light emitting region EA52 may be provided in a zigzag shape on a plane. In this case, the first and second light emitting regions EA51 and EA52 may be substantially the same as the first and second light emitting regions EA41 and EA42 of fig. 8, respectively.

For example, in the first light-emitting region EA51, the plurality of concave portions 131 arranged side by side in the first horizontal direction HL1 may be arranged in a zigzag shape with the plurality of concave portions 131 arranged side by side in the second horizontal direction HL 2. Alternatively, the inner angle of a triangle generated when the centers of three adjacent recesses 131 are connected to each other may be set to an acute angle. In this case, the adjacent recesses 131 may be disposed at regular intervals and the intervals correspond to S2 in the drawing.

Accordingly, in comparison with fig. 8, the distance S2 between adjacent recesses 131 of fig. 9 may be smaller than the distance S1 between adjacent recesses 131 of fig. 8.

In this manner, the plurality of first concave portions 131 are arranged in a zigzag shape or arranged such that the inner angle of a triangle generated when the centers of three adjacent concave portions 131 are connected to each other is an acute angle. As a result, the recesses 131 in the second horizontal direction HL2 may be disposed between the recesses 131 in the first horizontal direction HL1, and thus the number of the recesses 131 disposed per unit area may be greater than that of the exemplary embodiment of fig. 8. The number of the recesses 131 provided per unit area increases, thereby more improving light extraction efficiency on the front of the organic light emitting display device through the recesses 131.

Also, in fig. 8 and 9, a vertical length L11 of the first light emitting area EA41 may be greater than a vertical length L12 of the second light emitting area EA 42. Further, a horizontal length W31 of the first light emitting area EA41 may be substantially equal to a horizontal length W32 of the second light emitting area EA 42. That is, the light emitting area of the first light emitting area EA41 may be larger than the light emitting area of the second light emitting area EA 42. Therefore, an organic light emitting element having low efficiency is disposed in a sub-pixel having a large light emitting area, thereby improving the life of the organic light emitting element.

Further, a diameter D1 of the first concave portion 131 of the first light emitting area EA41 may be larger than a diameter D2 of the second concave portion 331 of the second light emitting area EA 42.

The shapes of the first and second light emitting areas EA41 and EA42 according to the present disclosure are not limited thereto, and may be formed as shown in fig. 10.

Fig. 10 is a plan view illustrating another shape in a light emitting region of an organic light emitting display device according to the present disclosure.

Referring to fig. 10, a vertical length L11 of a first light emitting area EA61 of the organic light emitting display device may be substantially equal to a vertical length L22 of a second light emitting area EA62, and a horizontal length W41 of the first light emitting area EA61 may be less than a horizontal length W42 of the second light emitting area EA 62. That is, the light emitting area of the light emitting region may be adjusted by adjusting the horizontal lengths of the light emitting regions EA61 and EA 62. Therefore, an organic light emitting element having low efficiency is disposed in a sub-pixel having a large light emitting area, thereby improving the life of the organic light emitting element.

This configuration will be described in detail below with reference to fig. 11.

Fig. 11 is a cross-sectional view of a portion of a light emitting region of an organic light emitting display device according to a fourth exemplary embodiment of the present disclosure of fig. 8, taken along line E-F.

Referring to fig. 11, the organic light emitting display device according to the fourth exemplary embodiment of the present disclosure includes a first light emitting area EA41 and a second light emitting area EA 42. In the first and second light emitting regions EA41 and EA42, protective layers 130 and 330 are disposed on the plurality of insulating layers 110 and 120, respectively.

In this case, a plurality of concave portions 131 and 331 are formed in the protective layers 130 and 330, respectively. The diameter D1 of the first recess 131 provided in the first light emitting area EA41 may be larger than the diameter D2 of the second recess 331 provided in the second light emitting area EA 42. Also, a horizontal length W31 of the first light emitting area EA41 may be equal to a horizontal length W32 of the second light emitting area EA 42.

As such, the diameter D2 of the second recess 331 is smaller than the diameter D1 of the first recess 131, and the horizontal length W31 of the first light emitting area EA41 is substantially equal to the horizontal length W32 of the second light emitting area EA42, so the second recess 331 may be disposed more densely in the horizontal direction than the first recess 131.

As a result, in the second light emitting area EA42, the number of times light generated from the organic light emitting layer 350 disposed on the protective layer 330 having the plurality of second recesses 331 may hit the plurality of second recesses 331 may be increased. Therefore, in the second light emitting area EA42, color shift with respect to a viewing angle can be reduced.

Also, the variation in the optical path length based on the shape of the concave portions 131 and 331 of the protective layers 130 and 330 is a main factor capable of reducing color shift for viewing angles. As parameters for determining the shape of the protective layer, the diameter D, the height H, and the gap G between the concave portions 131 and 331 and the adjacent concave portions 131 and 331, which are formed on the protective layers 130 and 330, are included.

Here, the diameters D1 and D2 of the concave portions 131 and 331 formed in the first light emitting region EA41 and the second light emitting region EA42 may be formed in the range of 2 μm to 6 μm. When the diameters D1 and D2 of the recesses 131 and 331 are less than 2 μm, it is difficult to form the recesses due to the process. Further, when the diameters D1 and D2 of the recesses 131 and 331 exceed 6 μm, color shift for viewing angle may be largely generated by the recesses in the light emitting region.

Accordingly, the diameters D1 and D2 of the concave portions 131 and 331 are 2 μm to 6 μm, thereby reducing color shift for viewing angles.

Further, the heights H1 and H2 of the concave portions 131 and 331 formed in the first light emitting region EA41 and the second light emitting region EA42 may be formed in the range of 0.05 μm to 2 μm. When the heights H1 and H2 of the concave portions 131 and 331 are less than 0.05 μm, the heights H1 and H2 of the concave portions are too low, and thus the reflective layers 141 and 341 provided on the concave portions 131 and 331 may be formed to be substantially flat. Therefore, when light emitted from the organic light emitting element 350 hits the reflective layers 141 and 341, the light hits a substantially flat surface, and thus the effect is the same as the case where the concave portions 131 and 331 are not formed on the protective layers 130 and 330. Further, when the heights H1 and H2 of the concave portions 131 and 331 exceed 2 μm, color shift with respect to a viewing angle may be largely generated.

Accordingly, the heights H1 and H2 of the concave portions 131 and 331 are 0.05 μm to 2 μm, thereby reducing color shift for viewing angles.

Further, the gaps G1 and G2 between the concave portions 131 and 331 and the other adjacent concave portions 131 and 331 formed in the first light emitting region EA41 and the second light emitting region EA42 may be, for example, 1 μm to 2 μm. When the gaps G1 and G2 are less than 1 μm, there is difficulty in the process of forming the concave portions 131 and 331, and when the gaps G1 and G2 exceed 2 μm, color shift with respect to viewing angles may be largely generated.

Accordingly, gaps G1 and G2 between the concave portions 131 and 331 and other adjacent concave portions 131 and 331 are 1 μm to 2 μm, thereby reducing color shift depending on the viewing angle.

The organic light emitting display device according to the fourth exemplary embodiment adjusts the diameters and heights of the plurality of recesses 131 and 331 formed in the respective light emitting regions and the gaps between the recesses 131 and 331 and other adjacent recesses 131 and 331. Accordingly, color shift for a viewing angle of each light emitting region of the organic light emitting display device can be reduced.

Also, an example in which the foregoing light emitting region is applied in an organic light emitting display device in which three sub-pixels constitute one pixel will be described below.

Fig. 12 is a plan view illustrating a light emitting region of an organic light emitting display device according to a fifth exemplary embodiment of the present disclosure. An organic light emitting display device according to a fifth exemplary embodiment of the present disclosure may include the same components as the foregoing exemplary embodiments. Descriptions overlapping with the foregoing exemplary embodiment may be omitted or simplified below. In addition, like components have like reference numerals.

Referring to fig. 12, in an organic light emitting display device according to a fifth exemplary embodiment of the present disclosure, one pixel P includes a first sub-pixel SP11, a second sub-pixel SP52, and a third sub-pixel SP 53. The first, second, and third sub-pixels SP11, SP52, and SP53 include a first light emitting area EA11, a second light emitting area EA72, and a third light emitting area EA73, respectively.

The first light-emitting region EA11, the second light-emitting region EA72, and the third light-emitting region EA73 include a plurality of concave portions 131 and 331, respectively. In this case, the diameter D1 of the concave portion 131 of the first light emitting area EA11 may be larger than the diameter D2 of the concave portions 331 of the second and third light emitting areas EA72 and EA 73.

As a result, the diameter of the recess composed of the plurality of recesses 131 and 331 is adjusted, thereby reducing color shift for viewing angle of each light emitting region of the organic light emitting display device. In fig. 12, a configuration in which the diameter D1 of the recess 131 provided in the first light emitting area EA11 is larger than the diameter D2 of the recess 331 provided in the second light emitting area EA72 and the third light emitting area EA73 is described, but the organic light emitting display device according to the fifth exemplary embodiment of the present disclosure is not limited thereto. The diameter D1 of the concave portion 131 of the first light emitting area EA11 may be smaller than the diameter D2 of the concave portions 331 of the second light emitting area EA72 and the third light emitting area EA 73.

Further, the diameters D2 of the concave portions 331 of the second and third light emitting areas EA72 and EA73 may be substantially equally formed, but the present disclosure is not limited thereto, and may be formed as shown in fig. 13.

Fig. 13 is a plan view illustrating an organic light emitting display device including a plurality of recesses having different diameters for each light emitting region.

Referring to fig. 13, a diameter D1 of the plurality of recesses 131 disposed in the first light emitting area EA11 may be larger than a diameter D2 of the plurality of recesses 331 disposed in the second light emitting area EA 72. A diameter D2 of the plurality of recesses 331 provided in the second light emitting area EA72 may be larger than a diameter D3 of the plurality of recesses 431 provided in the third light emitting area EA 83.

That is, the diameters D1, D2, and D3 of the plurality of recesses 131, 331, and 431 provided in the first, second, and third light emitting regions EA11, EA72, and EA83 may be different from each other.

Also, fig. 13 illustrates a configuration in which the diameter D1 of the plurality of recesses 131 provided in the first light-emitting area EA11 is larger than the diameter D2 of the plurality of recesses 331 provided in the second light-emitting area EA72 and the diameter D2 of the plurality of recesses 331 provided in the second light-emitting area EA72 is larger than the diameter D3 of the plurality of recesses 431 provided in the third light-emitting area EA 83. However, exemplary embodiments of the present disclosure are not limited thereto, and diameters of the plurality of concave portions 131, 331, and 431 provided in the first, second, and third light emitting areas EA11, EA72, and EA83 may be different from each other.

Therefore, in the respective light emitting regions where the organic light emitting elements emit light having different colors, the diameters and arrangement structures of the plurality of concave portions are adjusted in consideration of color shift for a viewing angle and light efficiency on the front of each organic light emitting element. Thus, color shift for viewing angle and light extraction efficiency on the front can be improved.

This structure will be described in detail below with reference to fig. 14.

Fig. 14 is a cross-sectional view of a light emitting region of the organic light emitting display device of fig. 13 taken along line G-H.

Referring to fig. 14, protective layers 130, 330, and 430 including a plurality of recesses 131, 331, and 431 are included in the first light emitting region EA11, the second light emitting region EA72, and the third light emitting region EA83, respectively.

In this case, the concave portion 131 in the first light emission region EA11 is disposed adjacent to other concave portions 131 with a predetermined gap G1. The recess 331 in the second light emitting area EA72 is disposed adjacent to the other recesses 331 with a predetermined gap G2. Further, the recesses 431 in the third light emitting area EA83 are disposed adjacent to other recesses 431 with a predetermined gap G3.

In this case, the diameter D1 of the recess 131 in the first light emitting area EA11 may be larger than the diameter D2 of the recess 331 provided in the second light emitting area EA 72. A diameter D2 of the recess 331 in the second light emitting area EA72 may be larger than a diameter D3 of the recess 431 in the third light emitting area EA 83.

Further, the shape of the organic light emitting element EL disposed in each light emitting region EA11, EA72, and EA83 may be formed according to the shape of the recesses 131, 331, and 431 disposed in each light emitting region EA11, EA72, and EA 83.

As such, the plurality of concave portions 131, 331, and 431 are formed in the first, second, and third light emitting regions EA11, EA72, and EA83, thereby improving color shift with respect to a viewing angle. Further, a plurality of recesses 131, 331, and 431 having different diameters are included in the respective light emitting regions EA11, EA72, and EA83, thereby changing the light extraction efficiency characteristics on the front side of each light emitting region EA11, EA72, and EA 83.

Next, a light emitting region of an organic light emitting display device according to a sixth exemplary embodiment of the present disclosure will be described below.

Fig. 15 is a plan view illustrating a light emitting region of an organic light emitting display device according to a sixth exemplary embodiment of the present disclosure. An organic light emitting display device according to a sixth exemplary embodiment of the present disclosure may include the same components as those of the foregoing exemplary embodiments. Descriptions overlapping with the foregoing exemplary embodiment may be omitted or simplified below. In addition, like components have like reference numerals.

Referring to fig. 15, a light emitting region of an organic light emitting display device according to a sixth exemplary embodiment of the present disclosure may be divided into a first light emitting region EA11, a second light emitting region EA82, and a third light emitting region EA 13. In this case, the first light emitting region EA11, the second light emitting region EA82, and the third light emitting region EA13 may emit different colors of light.

In addition, the first and third light emitting regions EA11 and EA13 may include a plurality of recesses 131, and the second light emitting region EA82 may not include recesses.

This configuration will be described in detail below with reference to fig. 16.

Fig. 16 is a cross-sectional view of a light emitting region of an organic light emitting display device according to a sixth exemplary embodiment of the present disclosure, taken along line I-J.

Referring to fig. 16, in the first and third light emitting areas EA11 and EA13 of the organic light emitting display device according to the sixth exemplary embodiment of the present disclosure, a plurality of recesses 131 are formed on the protective layer 130, and in the second light emitting area EA82, the protective layer 530 may be formed flat. Accordingly, the reflective layer 541 and the organic light emitting elements 540, 550, and 560 disposed on the protective layer 530 may also be formed flatly.

As such, the first and third light emitting regions EA11 and EA13 include a plurality of recesses 131, and the second light emitting region EA82 is formed flat, thereby improving light efficiency on the front of the organic light emitting display device.

In detail, in a light emitting region having low light efficiency on the front of the organic light emitting display device, a protective layer is formed flat, thereby improving light efficiency on the front. In a light-emitting region where improvement of color shift for viewing angle is required, a plurality of recesses are formed in the protective layer, thereby improving color shift for viewing angle.

As such, in the organic light emitting display device according to the sixth exemplary embodiment, in the pixel including the plurality of sub-pixels, the viewing angle improvement structure is not formed on the protective layer provided in at least one sub-pixel among the plurality of sub-pixels, thereby improving light efficiency on the front of the organic light emitting display device. In this case, in the sixth exemplary embodiment, the concave portion is described as an example of the viewing angle improvement structure, but is not limited thereto.

Next, an organic light emitting display device according to a seventh exemplary embodiment of the present disclosure will be described below.

Fig. 17 is a plan view illustrating a light emitting region of an organic light emitting display device according to a seventh exemplary embodiment of the present disclosure. An organic light emitting display device according to a seventh exemplary embodiment of the present disclosure may include the same components as the foregoing exemplary embodiments. Descriptions overlapping with the foregoing exemplary embodiment may be omitted or simplified below. In addition, like components have like reference numerals.

Referring to fig. 17, the organic light emitting display device according to the seventh exemplary embodiment of the present disclosure includes a first light emitting area EA11, a second light emitting area EA82, and a third light emitting area EA 23. In this case, the first light emitting area EA11 may include a plurality of recesses 131, but the second light emitting area EA82 may not include the recesses 131. In addition, the third light emitting area EA23 may include a plurality of protrusions 231. This configuration will be described in detail below with reference to fig. 18.

Fig. 18 is a cross-sectional view of an organic light emitting display device taken along the line K-L according to a seventh exemplary embodiment of the present disclosure.

Referring to fig. 18, the first light emitting area EA11 of the organic light emitting display device according to the seventh exemplary embodiment of the present disclosure includes a plurality of recesses 131 formed on a protective layer 130, and the second light emitting area EA82 includes a protective layer 530 that is formed flat. Also, the third light emitting area EA23 may include a plurality of convex parts 231.

As such, the first light emitting region EA11 includes a plurality of concave portions 131, the third light emitting region EA23 includes a plurality of convex portions 231, and the second light emitting region EA82 is formed flat, thereby improving light efficiency on the front of the organic light emitting display device.

In detail, in a light emitting region having low light efficiency on the front of the organic light emitting display device, a protective layer is formed flat, thereby improving light efficiency on the front. In a light-emitting region where improvement of color shift for viewing angle is required, a plurality of concave portions or a plurality of convex portions are formed in the protective layer, thereby improving color shift for viewing angle.

As such, in the organic light emitting display device according to the seventh exemplary embodiment, in the pixel including the plurality of sub-pixels, the viewing angle improvement structure is not included on the protective layer provided in at least one sub-pixel among the plurality of sub-pixels, thereby improving light efficiency on the front of the organic light emitting display device. Further, in the seventh exemplary embodiment, the plurality of concave portions 131 and the plurality of convex portions 231 are described above as examples of the viewing angle improving structure, but not limited thereto.

In the exemplary embodiment of the present disclosure, in each light emitting region, a plurality of concave portions or a plurality of convex portions are formed on the protective layer, or the protective layer is formed flat. That is, a configuration in which a plurality of concave portions or a plurality of convex portions are provided on the protective layer may be applied in combination. For example, the present disclosure may be implemented as shown in fig. 19 and 20.

Fig. 19 is a plan view illustrating a light emitting region of an organic light emitting display device according to an exemplary embodiment extended based on a seventh exemplary embodiment of the present disclosure. Fig. 20 is a sectional view taken along line M-N of the plan view of fig. 19.

Referring to fig. 19 and 20, the first light-emitting region EA21 includes a plurality of convex portions 231, and the third light-emitting region EA13 includes a plurality of concave portions 131. In addition, the protective layer 530 and the organic light emitting elements 540, 550, and 560 disposed in the second light emitting area EA82 may be formed flat. As a result, light efficiency on the front of the organic light emitting display device and color shift for viewing angle can be adjusted for each light emitting region.

As described above, in the organic light emitting display device according to the present disclosure, the light emitting region includes a plurality of concave or convex portions, or includes a plurality of concave or convex portions only in a portion of the light emitting region, thereby improving both the light efficiency on the front of the organic light emitting display device and the color shift with respect to the viewing angle.

In the above, the size and shape of the light emitting region included in each sub-pixel, and the size, height, gap, and the like of the concave or convex portion included in the light emitting region are described. Hereinafter, a bank layer for defining a light emitting region of each sub-pixel and a concave or convex portion included in the light emitting region will be described in detail.

Fig. 21 is a plan view illustrating a light emitting region of an organic light emitting display device according to an eighth exemplary embodiment of the present disclosure.

Referring to fig. 21, each sub-pixel SP included in the organic light emitting display device according to the eighth exemplary embodiment of the present disclosure is formed with a bank layer 736 and a plurality of recesses 731 spaced apart from each other at regular intervals in a light emitting region, the bank layer 736 including an opening 736b for defining the light emitting region. The opening 736b may have a predetermined shape, such as a quadrangle, on a plane, but is not limited thereto. A plurality of recesses 731 may be provided in the light emitting region defined by the opening 736 b.

Each sub-pixel SP including the recess 731 may be identical or substantially identical to the sub-pixel described with reference to fig. 2 to 20.

Hereinafter, an example in which the viewing angle improving structure is constituted by the concave portion and other examples in which the viewing angle improving structure is constituted by the convex portion will be described.

Fig. 22 and 23 are cross-sectional views of a light emitting region of an organic light emitting display device according to an eighth exemplary embodiment of the present disclosure, taken along line O-P.

Referring to fig. 22, in each sub-pixel included in the organic light emitting display device according to the eighth exemplary embodiment of the present disclosure, an insulating layer 710 and a protective layer 730 having a plurality of recesses 731 are disposed on a substrate 700, and an organic light emitting element EL is disposed on the protective layer 730.

In detail, the protective layer 730 includes a viewing angle improvement structure composed of a plurality of recesses 731 spaced apart from each other at regular intervals.

A first electrode 740, an organic light emitting layer 750, and a second electrode 760 of the organic light emitting element EL may be sequentially disposed on the protective layer 730. In this case, the shapes of the first electrode 740, the organic light emitting layer 750, and the second electrode 760 may correspond to the shape of the recess 731 formed on the protective layer 730.

As described above, in the organic light emitting display device according to the eighth exemplary embodiment of the present disclosure, the plurality of recesses 731 are provided in the light emitting region of each sub-pixel SP, thereby compensating for color shift on the side of the organic light emitting display device.

Each of the subpixels SP included in the organic light emitting display device according to the eighth exemplary embodiment of the present disclosure is disposed on the protective layer 730 and the first electrode 740 and may further include a bank layer 736, and the bank layer 736 includes a slanted opening 736b exposing the first electrode 740. The second electrode 760 disposed on the bank layer 736 has the same shape as the bank layer 736. In this case, light emitted from the organic light emitting layer 750 is reflected on the inclined opening 736b of the bank layer 736, and more particularly, on the second electrode 760 disposed on the opening 736b of the bank layer 736 to be extracted to the front of the organic light emitting display device.

In other words, each of the sub-pixels SP compensates for color shift on the side due to the plurality of recesses 730 spaced apart from each other at regular intervals, and light emitted from the organic light emitting layer 750 is reflected on the second electrode 760 disposed on the inclined opening 736b of the bank layer 736 to be collected in the light emitting region, thereby improving light efficiency on the front of the organic light emitting display device.

Referring to fig. 22, each sub-pixel SP included in the organic light emitting display device according to the eighth exemplary embodiment of the present disclosure compensates for color shift on the side due to the plurality of recesses 731 spaced apart from each other at regular intervals, and light emitted from the organic light emitting layer 750 is reflected on the inclined opening 736b of the bank layer 736 to be collected in the light emitting region, thereby improving light efficiency on the front of the organic light emitting display device. In this case, instead of the recess 731 shown in fig. 22, as shown in fig. 23, each sub-pixel SP includes a plurality of projections 831, a bank layer 736, and an opening of the bank layer 736 spaced apart from each other at regular intervals, thereby compensating color shift on the side and improving light efficiency on the front of the organic light emitting display device.

As shown in fig. 22 and 23, the slope of the inclined opening 736b of the bank layer 736 is constant, in which case the slope of the opening 736b may be 40 ° or more. In other words, the inclination angle of the opening 736b of the bank layer 736 may be 40 ° or more. When the inclination angle of the opening 736b is less than 40 °, light emitted from the organic light emitting layer 750 is reflected on the second electrode 760 disposed on the inclined opening 736b of the bank layer 736 without being collected in the light emitting region and may be emitted to the non-light emitting region, thereby deteriorating light efficiency on the front.

Fig. 24 and 25 are cross-sectional views of a light emitting region of an organic light emitting display device taken along the line O-P, which are extended based on an eighth exemplary embodiment of the present disclosure.

As shown in fig. 24 and 25, the inclined opening 736b of the bank layer 736 may have a concave shape. In other words, when the slope of the opening 736b of the bank layer 736 is less than 40 °, the opening 736b is concavely formed, thereby increasing light efficiency collected to the light emitting region.

Referring to fig. 21, in each sub-pixel SP included in an organic light emitting display device according to an eighth exemplary embodiment of the present disclosure, an opening 736b may have a predetermined shape, for example, a quadrangle, on a plane, and a plurality of recesses 731 are disposed in a light emitting region defined by the opening 736 b. However, an exemplary embodiment in which the opening is divided into two or more openings will be described below.

Fig. 26 is a plan view illustrating a light emitting region of an organic light emitting display device according to a ninth exemplary embodiment of the present disclosure.

Referring to fig. 26, each sub-pixel SP included in the organic light emitting display device according to the ninth exemplary embodiment of the present disclosure is formed with a bank layer 936, the bank layer 936 including an opening 936b for defining a light emitting region, and a plurality of recesses 931 spaced apart from each other at regular intervals in the light emitting region.

The opening 936b is divided into two or more openings, a partition wall 937 may be provided between the two or more openings 936b, and two or more recesses 931 may be provided in one opening 936ba or 936 bb.

For example, as shown in fig. 26, the opening 936b may be divided into a first opening 936ba and a second opening 936 bb. The first and second openings 936ba and 936bb may have a predetermined shape, such as a circle, an ellipse, or a polygon, on a plane, and a partition wall 937 may be provided between the first and second openings 936ba and 936 bb. In the first opening 936ba and the second opening 936bb, two or more recesses, for example, four recesses 931, may be provided, respectively.

The first opening 936ba and the second opening 936bb may have the same shape and area, and the number of recesses provided therein is the same as each other. However, the first opening 936ba and the second opening 936bb may have different shapes and areas, and the number of recesses provided therein may be different from each other.

Each of the sub-pixels SP including the plurality of recesses 931 spaced apart from each other at regular intervals may be identical or substantially identical to the sub-pixel described with reference to fig. 2 to 20.

Fig. 27 and 28 are cross-sectional views of a light emitting region of an organic light emitting display device according to a ninth exemplary embodiment of the present disclosure taken along line Q-R.

Referring to fig. 27, in each sub-pixel SP included in the organic light emitting display device according to the ninth exemplary embodiment of the present disclosure, an insulating layer 910 and a protective layer 930 having a plurality of recesses 931 are disposed on a substrate 900, and an organic light emitting element EL is disposed on the protective layer 930. In this case, the plurality of recesses 931 may be spaced apart from each other at regular intervals.

A first electrode 940, an organic light emitting layer 950, and a second electrode 960 of the organic light emitting element EL may be sequentially disposed on the protective layer 930. In this case, the shapes of the first electrode 940, the organic light emitting layer 950, and the second electrode 960 may correspond to the shape of the recess 931 formed on the protective layer 930.

Each of the subpixels SP included in the organic light emitting display device according to the ninth exemplary embodiment of the present disclosure is disposed on the protective layer 930 and the first electrode 940 and may further include a bank layer 936, the bank layer 936 including a slanted opening 936b exposing the first electrode 940.

As shown in fig. 27, the opening 936b may be divided into a first opening 936ba and a second opening 936 bb. The first and second openings 936ba and 936bb may have a predetermined shape, such as a circle, an ellipse, or a polygon, on a plane, and a partition wall 937 may be provided between the first and second openings 936ba and 936 bb.

The partition walls 937 include the same material as the bank layer 936 and may be formed simultaneously with the bank layer 936 by the same process as the bank layer 936.

The second electrode 960 disposed on the bank layer 936 has the same shape as the bank layer 936 and the partition walls 937. In this case, light emitted from the organic light emitting layer 950 is reflected on the inclined opening 936b of the bank layer 936 and the partition wall 937, and more particularly, on the second electrode 960 disposed on the opening 936b of the bank layer 936 and the partition wall 937 to be collected in the light emitting region.

Referring to fig. 28, each sub-pixel SP may include a plurality of protrusions 1031, an opening 936b of a bank layer 936, and a partition wall 937 instead of the recess 931 shown in fig. 27.

As described above, the two or more openings 936b of the bank layer 936 are formed and light emitted through the recess 931 or the protrusion 1031 is reflected on the partition wall, thereby improving light efficiency on the front of the organic light emitting display device.

As shown in fig. 27 and 28, the slope of the inclined openings 936b of the bank layer 936 is constant, and the slope of the openings 936b may be 40 ° or more. Further, the opening 936b and the partition wall 937 may have a concave shape as shown in fig. 24 and 25. The concave shapes of the opening 936b and the partition wall 937 may improve light efficiency on the front of the organic light emitting display device.

Fig. 29 is a plan view illustrating a light emitting region of an organic light emitting display device according to a tenth exemplary embodiment of the present disclosure.

Referring to fig. 29, each sub-pixel SP included in the organic light emitting display device according to the tenth exemplary embodiment of the present disclosure is formed with a bank layer 1136, and a microlens composed of a plurality of recesses 1131 disposed in a light emitting region, the bank layer 1136 including an opening 1136b for defining the light emitting region.

The opening 1136b is divided into two or more openings, a partition wall 1137 may be provided between the two or more openings 1136b, and one recess 1131 may be provided in one opening 1136 b. Each opening 1136b may have a predetermined shape, such as a circle, an ellipse, or a polygon, in plan, and a partition wall 1137 may be provided between the openings 1136 b.

The openings 1136b may have the same shape and area and the size or number of the recesses provided therein may be the same as each other, but the openings 1136b may have different shapes and areas and the size or number of the recesses provided therein may be different from each other.

Each sub-pixel SP including the recess 1131 may be identical or substantially identical to the sub-pixel described with reference to fig. 2 to 20.

Fig. 30 and 31 are cross-sectional views of a light emitting region of an organic light emitting display device according to a tenth exemplary embodiment of the present disclosure, taken along line S-W.

Referring to fig. 30, in each subpixel SP included in the organic light emitting display device according to the tenth exemplary embodiment of the present disclosure, an insulating layer 1110 and a protective layer 1130 having a plurality of recesses 1131 are disposed on a substrate 1100, and an organic light emitting element EL is disposed on the protective layer 1130.

In particular, a first electrode 1140, an organic light emitting layer 1150, and a second electrode 1160 of the organic light emitting element EL may be sequentially disposed on the protective layer 1130. In this case, the shapes of the first electrode 1140, the organic light emitting layer 1150, and the second electrode 1160 may correspond to the shape of the recess 1131 formed on the protective layer 1130.

Each of the subpixels SP included in the organic light emitting display device according to the tenth exemplary embodiment of the present disclosure is disposed on the protective layer 1130 and the first electrode 1140 and may further include a bank layer 1136, and the bank layer 1136 includes a slanted opening 1136b exposing the first electrode 1140. Each of the openings 1136b may have a predetermined shape, for example, a circle, an ellipse, or a polygon, and partition walls 1137 may be disposed between the openings 1136 b.

The partition walls 1137 include the same material as the bank layer 1136 and may be formed simultaneously with the bank layer 1136 by the same process as the bank layer 1136.

The second electrode 1160 disposed on the bank layer 1136 has the same shape as the bank layer 1136 and the partition wall 1137. In this case, light emitted from the organic light emitting layer 1150 is reflected on the inclined openings 1136b of the bank layer 1136 and the partition 1137, and particularly, on the second electrode 1160 disposed on the openings 1136b of the bank layer 1136 and the partition 1137, to be collected in the light emitting region.

Instead of the recess 1131 shown in fig. 30, as shown in fig. 31, each sub-pixel SP includes a convex 1231, an opening 1136b of a bank layer 1136, and a partition 1137, thereby improving color shift on the side and light efficiency on the front of the organic light emitting display device.

As shown in fig. 30 and 31, the inclined opening 1136b of the bank layer 1136 may have a concave shape. Alternatively, in the inclined openings 1136b of the bank layer 1136, as shown in fig. 27 and 28, the slope of the openings 1136b of the bank layer 1136 is constant, and the slope of the openings 1136b may be 40 ° or more.

As described above, in the organic light emitting display device according to the present disclosure, the light emitting region includes a plurality of concave or convex portions, and the emitted light is reflected on the inclined openings of the bank layer to be collected in the light emitting region, thereby improving both the light efficiency in the front and the color shift in the side.

Fig. 32 is a plan view illustrating one pixel of an organic light emitting display device according to an eleventh exemplary embodiment of the present disclosure.

Referring to fig. 32, in an organic light emitting display device according to an eleventh exemplary embodiment of the present disclosure, one pixel P includes a first sub-pixel SP91, a second sub-pixel SP92, and a third sub-pixel SP 93. The first, second, and third sub-pixels SP91, SP92, and SP93 include a first light emitting area EA91, a second light emitting area EA92, and a third light emitting area EA93, respectively.

The first light-emitting region EA91, the second light-emitting region EA92, and the third light-emitting region EA93 each include a plurality of concave portions 131, and the plurality of concave portions 131 are formed even around the light-emitting region.

In the protective layer, in order to form the concave portion 131, a mask having a hole corresponding to the position of the concave portion 131 may be prepared. In the process of exposing the protective layer using the mask having the holes, the concave portion 131 to be formed around the light-emitting region is greatly affected by exposure due to diffraction of light, as compared with the concave portion 131 to be formed inside the light-emitting region. A dimensional deviation between the recesses 131 formed in the light emitting region may occur. As a result, a deviation of color shift with respect to a viewing angle may occur in one sub-pixel.

To solve this problem, as shown in fig. 32, the concave portion 131 is formed up to the periphery of the light emitting regions EA91, EA92, and EA93, thereby reducing the difference in size between the concave portions 131 formed in the light emitting region and reducing the deviation of color shift for the viewing angle in one sub-pixel. In this case, the concave portion 131 is formed on the protective layer, and the aforementioned effect can be obtained by forming the protective layer having a non-flat shape including the convex portion in addition to the concave portion.

That is, the uneven shape formed on the protective layer is formed in the opening of the bank layer and the region having the bank layer, thereby suppressing the deviation of the uneven shape provided in the light emitting region and reducing the color shift with respect to the viewing angle.

Fig. 33 is a plan view illustrating one pixel of an organic light emitting display device according to an exemplary embodiment extended based on an eleventh exemplary embodiment of the present disclosure.

Referring to fig. 33, the recess 131 formed in fig. 32 may be formed to extend to the entire surface of one pixel. In this case, a mask having holes over the entire surface or a mask having holes in a region corresponding to at least one pixel may be used.

As in fig. 32, the recesses 131 are formed up to the periphery of the light emitting regions EA91, EA92, and EA93, thereby reducing the dimensional deviation between the recesses 131 formed in the light emitting region and reducing the deviation of color shift with respect to the viewing angle in one sub-pixel. In this case, the concave portion 131 is formed on the protective layer, and the aforementioned effect can be obtained by forming the protective layer having a non-flat shape including the convex portion in addition to the concave portion.

That is, the uneven shape formed on the protective layer is formed in the opening of the bank layer and the region having the bank layer, thereby suppressing the deviation of the uneven shape provided in the light emitting region and reducing the color shift with respect to the viewing angle.

Fig. 34 is a sectional view taken along line T-U of the plan view of fig. 33.

Referring to fig. 34, in each of the subpixels SP included in the organic light emitting display device according to the eleventh exemplary embodiment of the present disclosure, an insulating layer 1210 and a protective layer 1230 having a plurality of concave portions 131 are disposed on a substrate 1200, and an organic light emitting element EL is disposed on the protective layer 1230.

In particular, on the protective layer 1230, a first electrode 1240, an organic light emitting layer 1250, and a second electrode 1260 of the organic light emitting element EL may be sequentially disposed. In this case, the shapes of the first electrode 1240, the organic light emitting layer 1250, and the second electrode 1260 may correspond to the shape of the recess 131 formed on the protective layer 1230.

Further, a bank layer 1236 having an opening 1236b corresponding to the light emitting region is formed on the first electrode 1240, and the recess 131 is formed even under the bank layer 1236. Therefore, it is possible to reduce the dimensional deviation between the concave portions 131 formed in the light emitting region and reduce the deviation of color shift with respect to the viewing angle in one sub-pixel.

Fig. 35A to 35D are diagrams illustrating color coordinates of white light according to viewing angles in a right direction, an upper direction, a left direction, and a lower direction from the center of an organic light emitting display device as a comparative example. Fig. 36A to 36D are diagrams illustrating color coordinates of white light according to viewing angles of right, upper, left, and lower directions from the center of an organic light emitting display device as an embodiment, and fig. 36A to 36D are measurement results of the organic light emitting display device according to fig. 2. In this case, the right direction, the upper direction, the left direction, and the lower direction of the organic light emitting display device may be represented by azimuth angles of 0 °,90 °,180 °, and 270 °, respectively. The color coordinate change Δ u 'v' represents a difference between a color coordinate at 0 ° and a color coordinate at 60 ° when the organic light emitting display device is viewed from the front, and the color coordinate u 'v' represents a 1976 uniform chromaticity table (UCS) coordinate defined by the international commission on illumination (CIE) 15.2. Further, when the color coordinate variation is 0.030 or less, color shift depending on a viewing angle perceived by a user may be minimized and an organic light emitting display device having a clearer image may be provided.

The viewing angles measured in fig. 35A to 35D are 0 ° to 60 °, and the viewing angles are divided and expressed as groups of 0 ° to 25 °, 30 ° to 40 °, and 45 ° to 60 °, with 5 ° intervals between the groups. The viewing angle of the starting point X is 0 °.

Boundary lines of the region 8, the region 12, the region 15, and the region 18 based on the oval representations shown in fig. 35A to 35D and fig. 36A to 36D represent color coordinates of the organic light emitting display device according to the comparative example and the example. Here, the region refers to a minimum difference threshold between two colors that can be recognized by a user by considering a perceptual feature of the user, and the region may be represented by a Just Noticeable Difference (JND). As the area decreases, the color shift depending on the viewing angle also decreases.

In addition, the white light emitted from the organic light emitting display device may be emitted as light of a slight blue color, for example, light of a pale blue color so that the glasses of the user feel clear and clean white. The color coordinates of the bluish white light may be a region located around the start point in the diagram and shifted in the lower left side of the start point, which is a special region (spec), and exhibits color coordinates based on the front and viewing angles in the special region. When the special area is located within the area 12, sharper image quality can be provided. In addition, the specific regions shown in fig. 35A to 36D do not limit the gist of the present disclosure and may be varied according to consumer needs.

The graphs of fig. 35A to 35D are results obtained by measuring color coordinates of an organic light emitting display device to which a protective layer without concave or convex portions is applied.

Referring to fig. 35A, fig. 35A is a diagram obtained by measuring color coordinates of white light in a right direction (0 ° azimuth angle) when viewed from the center front of the organic light emitting display device. As the viewing angle goes from 0 ° toward 60 °, the color coordinates are far from the starting point and the color coordinates in front and at the viewing angle are distributed in the area 16. In this case, the color coordinate change Δ u 'v' 0R is about 0.033.

Referring to fig. 35B, when viewed from the front of the center of the organic light emitting display device, fig. 35B is a diagram obtained by measuring color coordinates of white light in an upper direction (90 ° azimuth angle). The color coordinates in front and in view are distributed in a special area within the area 12. In this case, the color coordinate change Δ u 'v' 90R is about 0.021.

Referring to fig. 35C, when viewed from the front of the center of the organic light emitting display device, fig. 35C is a diagram obtained by measuring color coordinates of white light in the left direction (180 ° azimuth angle). The color coordinates in front and in view are distributed in a special border line within the area 15. In this case, the color coordinate change Δ u 'v' 180R is about 0.031.

Referring to fig. 35D, when viewed from the center front of the organic light emitting display device, fig. 35D is a diagram obtained by measuring color coordinates of white light in a lower direction (270 ° azimuth angle). The color coordinates in front and in view are distributed in a special area within the area 14. In this case, the color coordinate change Δ u 'v' 270R is about 0.019.

Fig. 36A to 36D are diagrams obtained by measuring color coordinates of an organic light emitting display device to which the structure of the first exemplary embodiment in fig. 2 is applied.

Referring to fig. 36A, fig. 36A is a diagram obtained by measuring color coordinates of white light in a right direction (0 ° azimuth angle) when viewed from the center front of the organic light emitting display device. The color coordinates in front and in viewing angle are distributed in the area 9. In this case, the color coordinate change Δ u 'v' 0E is about 0.015. Further, compared to the comparative example of fig. 35A, the example is located in the region 9, and thus it is possible to reduce color coordinate variation and to reduce color shift depending on the viewing angle.

Referring to fig. 36B, when viewed from the front of the center of the organic light emitting display device, fig. 36B is a diagram obtained by measuring the color coordinates of white light in the upper direction (90 ° azimuth angle). The color coordinates in front and in view are distributed in the area 11. In this case, the color coordinate change Δ u 'v' 90E is about 0.009. Further, compared to the comparative example of fig. 35B, the embodiment is located in the region 11, and thus it is possible to reduce color coordinate variation and to reduce color shift depending on the viewing angle.

Referring to fig. 36C, fig. 36C is a diagram obtained by measuring color coordinates of white light in a left direction (180 ° azimuth angle) when viewed from the front of the center of the organic light emitting display device. The color coordinates in front and in viewing angle are distributed in the area 10. In this case, the color coordinate change Δ u 'v' 180E is about 0.015. Further, compared to the comparative example of fig. 35C, the example is located in the region 10, and thus it is possible to reduce color coordinate variation and to reduce color shift depending on the viewing angle.

Referring to fig. 36D, fig. 36D is a diagram obtained by measuring color coordinates of white light in a lower direction (270 ° azimuth angle) when viewed from the center front of the organic light emitting display device. The color coordinates in front and in view are distributed in the area 8. In this case, the color coordinate change Δ u 'v' 270E is about 0.004. Further, compared to the comparative example of fig. 35D, the embodiment is located in the region 8, and thus it is possible to reduce color coordinate variation and to reduce color shift depending on the viewing angle.

When comparing the color coordinate distributions of the comparative example and the example according to the viewing angle and the color coordinate variation, in the example, it can be confirmed that the distribution of the color coordinates is located in an area close to the starting point and the color coordinate variation is reduced, compared to the comparative example. That is, the color coordinate variation of the white light emitted from the organic light emitting display device in the embodiment including the protective layer having the concave or convex portions is smaller than the maximum value of the color coordinate variation of the white light emitted from the organic light emitting display device in the comparative example including the flat protective layer. In addition, in the organic light emitting display device of the comparative example, the color coordinates based on the viewing angle may be located within the region 12. Therefore, when the embodiment is applied, color shift depending on a viewing angle can be reduced and efficiency of the organic light emitting element can be improved.

Similar to fig. 32 and 33, even when a plurality of concave or convex portions are formed even around the light emitting region, almost the same effect can be obtained. As described above, the formation of a plurality of concave or convex portions around the light-emitting region is to reduce the deviation of color shift depending on the viewing angle in one sub-pixel by minimizing the difference in size of the plurality of concave or convex portions to be formed inside and around the light-emitting region. Therefore, an organic light-emitting display device in which a plurality of concave or convex portions are formed in a part or the entire pixel region around a light-emitting region can have almost the same effect as an organic light-emitting display device in which a plurality of concave or convex portions are formed only in a light-emitting region.

Exemplary embodiments of the present disclosure can also be described as follows:

according to an aspect of the present disclosure, there is provided a substrate for an organic light emitting display device, including: a protective layer, a first electrode, and a bank layer. The protective layer has a non-planar shape. The first electrode is on the protective layer and has the non-planar shape. The bank layer is on the protective layer and the first electrode and includes an opening for exposing the first electrode. The protective layer is located in the opening of the bank layer and a portion of a region having the bank layer. The non-flat shape formed on the protective layer reduces deviation of an optical path length for a viewing angle to minimize color shift for the viewing angle. Accordingly, the life of the organic light emitting display device may be improved.

The protective layer may include a plurality of concave portions or a plurality of convex portions, and the concave portions or the convex portions may be disposed to be spaced apart from adjacent concave portions or convex portions at regular intervals.

The plurality of concave portions or the plurality of convex portions may include a first concave portion and a second concave portion or a first convex portion and a second convex portion, and a third concave portion or a third convex portion adjacent to the second concave portion or the second convex portion may be further provided between the first concave portion and the second concave portion or between the first convex portion and the second convex portion to form a zigzag array.

The plurality of concave portions or the plurality of convex portions may be disposed in a region wider than the opening of the bank layer.

The plurality of concave portions or the plurality of convex portions may be provided on the entire surface of the protective layer.

The slope of the opening of the bank layer may be 40 ° or more, or the opening may have a curved shape.

The substrate may further include: a light emitting area including the opening of the bank layer, wherein the light emitting area may include a first light emitting area, a second light emitting area, and a third light emitting area, and a vertical length of the first light emitting area may be greater than a vertical length of the second light emitting area and a vertical length of the third light emitting area.

Vertical lengths of the second light emitting area and the third light emitting area may be different from each other.

The substrate may further include: a light emitting area including the opening of the bank layer, wherein the light emitting area includes a first light emitting area, a second light emitting area, and a third light emitting area, and a horizontal length of the first light emitting area may be smaller than a horizontal length of the second light emitting area and a horizontal length of the third light emitting area.

The horizontal lengths of the second light emitting region and the third light emitting region may be different from each other.

According to another aspect of the present disclosure, there is provided an organic light emitting display device including: a bank layer, a protective layer, and an organic light emitting layer. The protective layer has a viewing angle improving structure. The organic light emitting display device includes a plurality of pixels and sub-pixels constituting the pixels. The bank layer exposes a light emitting region of the sub-pixel and includes a slanted opening. The organic light emitting layer is disposed on the protective layer, and the organic light emitting layer follows a form of the viewing angle improvement structure. The viewing angle improving structure formed on the protective layer reduces deviation of an optical path length for a viewing angle to minimize color shift for the viewing angle. Accordingly, the life of the organic light emitting display device may be improved.

The organic light emitting display device may include two or more sub-pixels. The protective layer and the organic light emitting layer in at least one sub-pixel among the two or more sub-pixels do not include the viewing angle improvement structure.

The viewing angle improving structure may include a concave portion or a convex portion.

The diameter of the concave portion or the convex portion may be 2 μm to 6 μm.

The height of the concave portion or the convex portion may be 0.05 μm to 2 μm.

The concave portions or the convex portions include a plurality of concave portions or a plurality of convex portions, and each of the gaps between the concave portions and the gaps between the convex portions may be 1 μm to 2 μm.

The concave part or the convex part may include a plurality of concave parts or a plurality of convex parts, and the concave parts or the convex parts may be disposed such that all inner angles of a triangle formed when centers of three adjacent concave or convex parts are connected to each other become acute angles.

The sub-pixel comprises two or more sub-pixels. The protective layer of one of the two or more sub-pixels includes the concave portion, and the protective layers of the other sub-pixels include the convex portion.

The slope of the opening of the bank layer may be 40 ° or more, or the opening may have a curved shape.

The bank layer may include two or more openings exposing the light emitting region.

The components and effects of the components of the foregoing exemplary embodiments may be applied to a substrate of an organic light emitting display device and the organic light emitting display device.

The features, structures, effects, and the like described in the foregoing exemplary embodiments are included in at least one exemplary embodiment of the present disclosure, and are not particularly limited to only one exemplary embodiment. Furthermore, those skilled in the art to which exemplary embodiments pertain may combine or modify the features, structures, effects, etc., illustrated in each exemplary embodiment to achieve even further exemplary embodiments. Therefore, it should be construed that the matters related to the combination and modification are included in the scope of the present disclosure.

In the above description, the present disclosure has been described based on exemplary embodiments, but these exemplary embodiments are illustrative and not restrictive of the present disclosure, and those skilled in the art will understand that various modifications and applications not illustrated in the above description may be made without departing from the scope of essential characteristics of the exemplary embodiments. For example, each component described in detail in the exemplary embodiments can be modified and implemented.

Although the exemplary embodiments of the present disclosure have been described in detail with reference to the accompanying drawings, the present disclosure is not limited thereto, and may be embodied in many different forms without departing from the technical idea of the present disclosure. Accordingly, the exemplary embodiments of the present disclosure are provided only for illustrative purposes, and are not intended to limit the technical concept of the present disclosure. The scope of the technical idea of the present disclosure is not limited thereto. Therefore, it should be understood that the above-described exemplary embodiments are illustrative in all respects and not restrictive of the disclosure. The scope of the present disclosure should be construed based on the claims that follow, and all technical ideas within the equivalent scope thereof should be construed to fall within the scope of the present disclosure.

Claims (18)

1. A substrate for an organic light emitting display device, comprising:

a protective layer having a non-planar shape;

a first electrode on the protective layer, the first electrode having the non-planar shape; and

a bank layer on the protective layer and the first electrode, the bank layer including an opening for exposing the first electrode,

wherein the protective layer is located in the opening of the bank layer and a portion of the region having the bank layer,

wherein the sub-pixels of the organic light emitting display device include at least two or more sub-pixels, the protective layer includes a plurality of concave portions and does not include convex portions within the opening of the bank layer in a light emitting region of one sub-pixel, and the protective layer includes a plurality of convex portions and does not include concave portions within the opening of the bank layer in light emitting regions of other sub-pixels.

2. The substrate of claim 1, wherein the protective layer is configured to reduce color shift for viewing angles.

3. The substrate according to claim 1, wherein the concave portions or the convex portions are provided to be spaced apart from adjacent concave portions or convex portions at regular intervals.

4. The substrate of claim 3, wherein the plurality of recesses or the plurality of protrusions comprise a first recess and a second recess or a first protrusion and a second protrusion, and

wherein a third concave portion or a third convex portion adjacent to the second concave portion or the second convex portion is further provided between the first concave portion and the second concave portion or between the first convex portion and the second convex portion to form a zigzag array.

5. The substrate according to claim 3, wherein the plurality of concave portions or the plurality of convex portions are provided in a region wider than the opening of the bank layer.

6. The substrate according to claim 3, wherein the plurality of concave portions or the plurality of convex portions are provided on an entire surface of the protective layer.

7. The substrate according to claim 1, wherein a slope of the opening of the bank layer is 40 ° or more, or the opening has a curved shape.

8. The substrate of claim 1, further comprising:

a light emitting area including the opening of the bank layer,

wherein the light emitting region includes a first light emitting region, a second light emitting region, and a third light emitting region, and

the vertical length of the first light emitting region is greater than the vertical length of the second light emitting region and the vertical length of the third light emitting region.

9. The substrate according to claim 8, wherein vertical lengths of the second light emitting area and the third light emitting area are different from each other.

10. The substrate of claim 1, further comprising:

a light emitting area including the opening of the bank layer,

wherein the light emitting region includes a first light emitting region, a second light emitting region, and a third light emitting region, and

the horizontal length of the first light-emitting region is smaller than the horizontal length of the second light-emitting region and the horizontal length of the third light-emitting region.

11. The substrate of claim 10, wherein horizontal lengths of the second and third light emitting areas are different from each other.

12. An organic light emitting display device including a plurality of pixels and sub-pixels constituting the pixels, the organic light emitting display device comprising:

a bank layer exposing the light emitting region of the sub-pixel and including a slanted opening;

a protective layer including a viewing angle-improving structure; and

an organic light emitting layer on the protective layer, the organic light emitting layer following a form of the viewing angle improving structure,

wherein the sub-pixels include at least two or more sub-pixels, the protective layer includes a plurality of concave portions and does not include convex portions within the opening of the bank layer in a light emitting region of one sub-pixel, and the protective layer includes a plurality of convex portions and does not include concave portions within the opening of the bank layer in light emitting regions of other sub-pixels.

13. The organic light-emitting display device according to claim 12, wherein the diameter of the concave portion or the convex portion is 2 μm to 6 μm.

14. The organic light-emitting display device according to claim 12, wherein the height of the concave portion or the convex portion is 0.05 μm to 2 μm.

15. The organic light-emitting display device according to claim 12, wherein each of a gap between the concave portions and a gap between the convex portions is 1 μm to 2 μm.

16. The organic light-emitting display device according to claim 12, wherein the concave or convex portions are arranged such that all internal angles of a triangle formed when centers of three adjacent concave or convex portions are connected to each other become acute angles.

17. The organic light-emitting display device according to claim 12, wherein a slope of the opening of the bank layer is 40 ° or more, or the opening has a curved shape.

18. The organic light-emitting display device according to claim 12, wherein the bank layer comprises two or more openings exposing the light-emitting region.

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