Light emitting display device

Abstract

Disclosed is a light emitting display device in which an optical compensation layer for compensating for an optical distance in each sub-pixel emitting light of different colors is provided together with formation of a thin film transistor array, thereby reducing a driving voltage value required to drive an organic stack and improving process performance.

Description

[0001] This application claims the benefit of Korean Patent Application No. 10-2020-0183654, filed on December 24, 2020, which is incorporated herein by reference as if fully set forth herein. Technical Field

[0002] The present invention relates to a display device, and more particularly, to a light-emitting display device in which an optical compensation layer is provided, together with the formation of a thin-film transistor array, for compensating for optical distances in each sub-pixel configured to emit different colors of light, thereby reducing the driving voltage required to drive the organic stack and improving process performance. Background Technology

[0003] As society has recently entered the information age, the field of displays used to visually display electrical information signals has developed rapidly. To meet this development, various display devices with excellent performance, such as being thin, lightweight, and low power consumption, have been developed and have rapidly replaced traditional cathode ray tubes (CRTs).

[0004] Among them, light-emitting display devices that do not require a separate light source, achieve compactness and clear color display, and include light-emitting devices within the display panel are considered competitive applications.

[0005] When an optical compensation layer is provided in the organic stack between the anode and cathode to compensate for the optical distance in each sub-pixel configured to emit different colors of light, the optical compensation layer causes a difference in thickness between the anode and cathode, thereby increasing the driving voltage.

[0006] Furthermore, certain sub-pixels require optical compensation layers, thus necessitating separate masks, which reduces process yield. Summary of the Invention

[0007] Therefore, the present invention relates to a light-emitting display device that substantially overcomes one or more problems caused by the limitations and disadvantages of related technologies.

[0008] One object of the present invention is to provide a light-emitting display device in which an optical compensation layer is provided, together with the formation of a thin-film transistor array, for compensating for the optical distance in each sub-pixel configured to emit light of different colors, thereby reducing the driving voltage required to drive the organic stack and improving process performance.

[0009] Another object of the present invention is to provide a light-emitting display device in which an auxiliary optical compensation layer is formed by using the same mask as the light-emitting layer and a different material than the light-emitting layer to compensate for differences in optical distance between sub-pixels, thereby achieving additional fine optical distance adjustment required due to device differences.

[0010] Other advantages, objects, and features of the invention will be set forth in part in the description which follows, some of which will become apparent to those skilled in the art from the explanation thereof, or may be learned by practice of the invention. These objects and other advantages of the invention can be realized and obtained through the structures particularly pointed out in the specification, claims, and drawings.

[0011] To achieve these and other advantages and according to the purposes of the invention, as specifically and generally described herein, a light-emitting display device includes: a substrate comprising a first sub-pixel and a second sub-pixel; a first reflective electrode and a second reflective electrode respectively at the first sub-pixel and the second sub-pixel; a first optical compensation layer on the first reflective electrode; a first anode in contact with the first optical compensation layer and a second anode in contact with the second reflective electrode; a first unit having at least one first stack, the first stack comprising a first common layer, a first light-emitting layer emitting light having a first wavelength, and a second common layer sequentially stacked on the first anode; a second unit having at least one second stack, the second stack comprising the first common layer, a second light-emitting layer emitting light having a second wavelength shorter than the first wavelength, and the second common layer sequentially stacked on the second anode; and a cathode on the first unit and the second unit.

[0012] In another aspect of the invention, a light-emitting display device includes: a substrate having a first sub-pixel, a second sub-pixel, and a third sub-pixel; a first reflective electrode, a second reflective electrode, and a third reflective electrode at the first sub-pixel, the second sub-pixel, and the third sub-pixel, respectively; a first optical compensation layer on the first reflective electrode and a second optical compensation layer on the third reflective electrode, the second optical compensation layer having a thickness smaller than that of the first optical compensation layer; a first anode in contact with the first optical compensation layer, a second anode in contact with the second reflective electrode, and a third anode in contact with the second optical compensation layer; a dam portion overlapping the edges of the first anode, the second anode, and the third anode and opening up a first light-emitting portion, a second light-emitting portion, and a third light-emitting portion in the first sub-pixel, the second sub-pixel, and the third sub-pixel; a first common layer on the first light-emitting portion, the second light-emitting portion, the third light-emitting portion, and the dam portion; a first light-emitting layer, a second light-emitting layer, and a third light-emitting layer at the first light-emitting portion, the second light-emitting portion, and the third light-emitting portion, respectively; a second common layer on the first light-emitting portion, the second light-emitting portion, and the third light-emitting portion; and a cathode on the second common layer.

[0013] It should be understood that the foregoing general description and the following detailed description of the invention are illustrative and explanatory, and are intended to provide further explanation of the claimed invention. Attached Figure Description

[0014] The accompanying drawings, which are included to provide a further understanding of the invention and are incorporated in and constitute a part of this application, illustrate embodiments of the invention and, together with the description, serve to explain the principles of the invention. In the drawings:

[0015] Figure 1 This is a cross-sectional view illustrating a light-emitting display device according to a first embodiment of the present invention;

[0016] Figure 2 This is a cross-sectional view illustrating a light-emitting display device according to a second embodiment of the present invention;

[0017] Figure 3 It is a diagram Figure 2 A detailed cross-sectional view of an example implementation;

[0018] Figure 4 This is a cross-sectional view illustrating a light-emitting display device according to a third embodiment of the present invention;

[0019] Figure 5 It is a diagram Figure 4 A detailed cross-sectional view of an example implementation;

[0020] Figure 6This is a cross-sectional view illustrating a light-emitting display device according to a fourth embodiment of the present invention;

[0021] Figure 7 This is a cross-sectional view illustrating a light-emitting display device according to a fifth embodiment of the present invention;

[0022] Figure 8 This is a cross-sectional view illustrating a light-emitting display device according to a sixth embodiment of the present invention;

[0023] Figure 9 This is a cross-sectional view illustrating a light-emitting display device according to a seventh embodiment of the present invention;

[0024] Figure 10 This is a cross-sectional view illustrating a light-emitting display device according to an eighth embodiment of the present invention;

[0025] Figure 11 This is a cross-sectional view illustrating a light-emitting display device according to a ninth embodiment of the present invention;

[0026] Figure 12 It is a cross-sectional view of the light-emitting device according to Test Example 1 and Test Example 2;

[0027] Figure 13 The graphs show the driving voltage-current density characteristics and driving voltage-current characteristics of the light-emitting devices according to Test Example 1 and Test Example 2. Detailed Implementation

[0028] Referring now to exemplary embodiments of the invention, some examples of which are illustrated in the accompanying drawings. In the following description of the embodiments and drawings, the same or similar reference numerals denote the same or similar parts throughout the application. In the following description of embodiments of the invention, detailed descriptions of known functions and constructions incorporated herein will be omitted where such detailed descriptions would obscure the gist of the invention. Furthermore, the names of elements used in the following description of embodiments of the invention have been chosen for ease of preparation of this application and may therefore differ from the names of parts in the actual product.

[0029] The shapes, dimensions, proportions, angles, and quantities given in the drawings for the purpose of describing embodiments of the invention are merely examples, and therefore the invention is not limited to the details shown. In the following description of embodiments, the terms "comprising," "including," and "having" should be interpreted as indicating the presence of one or more features, quantities, steps, operations, elements, or portions or combinations thereof described in this application, without excluding the possibility of the presence of other features, quantities, steps, operations, elements, portions, or combinations thereof, or the possibility of increasing them, unless the term "only" is used. It will be understood that singular expressions of elements encompass plural expressions unless otherwise stated.

[0030] When interpreting the elements included in the various embodiments of the present invention, it should be understood that the quantitative description of the characteristics of the elements includes a range of error, unless otherwise stated.

[0031] In the following description of the implementation, it will be understood that when expressing positional relationships, for example, when one element is described as being “above,” “over,” “below,” or “next to” another element, the two elements may be in direct contact with each other, or one or more other elements may be inserted between the two elements, unless the terms “exactly” or “directly” are used.

[0032] In the following description of the implementation, it will be understood that when expressing temporal relationships, for example when using terms that express the order of events, such as “after,” “following,” “next,” and “before,” these terms cover both sequential and discontinuous relationships between events, unless the terms “exactly” or “directly” are used.

[0033] In the following description of the embodiments, it will be understood that when the terms "first," "second," etc., are used to describe various elements, these terms are only used to distinguish the same or similar elements. Therefore, without departing from the technical scope of the present invention, the first element described below may be referred to as the second element.

[0034] The various features of the embodiments of the present invention can be combined or integrated with each other in part or in whole, and can be interoperable or driven in various technical ways. The various embodiments can be implemented independently of each other, or can be implemented together through their connection.

[0035] In the following description of the embodiments, the term "doped" refers to a material added to the material comprising the majority of the weight of the respective layer, having properties different from those of the material comprising the majority of the weight of the respective layer (materials with different properties, such as N-type and P-type materials, or organic and inorganic materials), with an content of less than 30 wt%. In other words, a "doped" layer is a layer in which the matrix material and the dopant material can be distinguished from each other based on their weight percentages. Furthermore, the term "undoped" layer refers to all cases other than those corresponding to the term "doped". For example, if the layer is formed from a single material or from a mixture of materials having the same or similar properties, then the layer can be an "undoped" layer. For example, if at least one of the materials forming the layer is P-type and none of the materials forming the layer are N-type, then the layer is an "undoped" layer. For example, if at least one of the materials forming the layer is organic and none of the materials forming the layer are inorganic, then the layer is an "undoped" layer. For example, if all the materials forming the layer are organic and at least one of the materials forming the layer is N-type and at least another of the materials is P-type, then the layer is a "doped" layer when the content of the N-type material is less than 30 wt% or the content of the P-type material is less than 30 wt%.

[0036] Figure 1 This is a cross-sectional view illustrating a light-emitting display device according to a first embodiment of the present invention.

[0037] like Figure 1 As shown, the light-emitting display device according to the first embodiment of the present invention includes: a substrate having a first sub-pixel SP1 and a second sub-pixel SP2. Figure 3 (100 shown in the figure); a first reflective electrode 110b and a second reflective electrode 110b' respectively disposed in the first sub-pixel SP1 and the second sub-pixel SP2; a first optical compensation layer 122 disposed on the first reflective electrode 110b; a first anode 110c configured to contact the first optical compensation layer 122; and a second anode 110c' configured to contact the second reflective electrode 110b'.

[0038] In addition, a first unit OS1 is disposed on the first anode 110c. The first unit OS1 sequentially includes a first common layer CML, a first light-emitting layer 153 configured to emit light having a first wavelength, and a second common layer CMU 144.

[0039] A second unit OS2 is disposed on the second anode 110c'. The second unit OS2 sequentially includes a first common layer CML, a second light-emitting layer 151 configured to emit light having a second wavelength shorter than the first wavelength, and a second common layer CMU144.

[0040] Each layer of the first unit OS1 and the second unit OS2 can be formed from organic materials, and can be formed by vapor deposition using the respective organic materials.

[0041] The cathode 160 is commonly disposed on the first unit OS1 and the second unit OS2. The cathode 160 can also be formed by vapor deposition in the same manner as the individual layers of the first unit OS1 and the second unit OS2.

[0042] In addition to the first light-emitting layer 153 and the second light-emitting layer 151, the first unit OS1 and the second unit OS2 commonly include a first common layer CML and a second common layer CMU 144. The first light-emitting layer 153 and the second light-emitting layer 151 are selectively disposed in the respective sub-pixels, and thus can be formed using a fine metal mask (FMM).

[0043] The first common layer CML and the second common layer CMU are distributed with sub-pixels above and below the first light-emitting layer 153 and the second light-emitting layer 151, and can be formed using a common mask having openings corresponding to each sub-pixel.

[0044] Furthermore, the first common layer CML relates to hole injection and transport, and may include a hole injection layer 141, a hole transport layer 142, and an electron blocking layer 143.

[0045] The hole injection layer 141 is formed of a material with low energy barrier and low surface resistance to the anodes 110c and 110c', so that holes from the anodes 110c and 110c' can be easily injected into the hole injection layer 141. For this purpose, the material of the hole injection layer 141 may include p-type dopants in the hole transport material.

[0046] Hole transport layer 142 can easily transport holes provided by hole injection layer 141 to light-emitting layers 153 and 151, and hole transport layer 142 is formed of hole transport material.

[0047] The electron blocking layer 143 is used to prevent excitons formed by the light-emitting layers 153 and 151 or electrons transported to the light-emitting layers 153 and 151 from moving to the hole transport layer 142.

[0048] In some cases, the hole injection layer 141 and the electron blocking layer 143 may be omitted, or they may be integrally formed with the hole transport layer 142.

[0049] The second common layer CMU 144 may include: a hole blocking layer HBL configured to prevent holes from escaping from the light-emitting layers 153 and 151; and an electron transport layer ETL configured to transport electrons. The hole blocking layer HBL and the electron transport layer ETL may be formed as different layers. The hole blocking layer HBL and the electron transport layer ETL may be formed separately.

[0050] Depending on the performance requirements of the display device, the first common layer CML and the second common layer CMU may further include additional layers integral with them, and may include matrix and dopant components contained in the light-emitting layers 153 and 151.

[0051] The light-emitting display device according to the present invention is structurally characterized in that a first optical compensation layer 122 is disposed between the first reflective electrode 110b and the first anode 110c, rather than disposed within the organic unit OS1 between the first anode 110c and the cathode 160. That is, the first optical compensation layer 122 is disposed between the first reflective electrode 110b and the first anode 110c before the organic material deposition process, thus allowing the first optical compensation layer 122 to be formed during the thin-film transistor array formation process performed by photolithography before the organic material deposition process. Therefore, compared to a structure in which the optical compensation layer is disposed within an organic stack (a unit formed of organic components; hereinafter, the first unit OS1 and the second unit OS2 may also be referred to as the first organic stack OS1 and the second organic stack OS2, respectively), the light-emitting display device according to the present invention does not require a separate fine metal mask and chamber for forming the first optical compensation layer 122. Therefore, since only the light-emitting layers 153 and 151 in the organic stack OS1 and OS2 require fine metal masks, the use of fine metal masks is reduced, thereby improving the process yield. Furthermore, the organic materials used to form the optical compensation layer are omitted, thus reducing the use of organic materials.

[0052] The function of the first optical compensation layer 122 will be described below.

[0053] In a light-emitting display device in which each sub-pixel emits light of a different color, the light resonates while being repeatedly reflected and re-reflected between the reflective electrode 110b and the cathode 160 in each sub-pixel. It is ultimately emitted through the cathode 160. In this case, the optimal light-emitting position varies depending on the color of the emitted light; therefore, a first optical compensation layer 122 is provided to position the light-emitting layer at a location suitable for the optimal optical distance for emitting light from the reflective electrode 110b. As the wavelength of the emitted light increases, the optical distance increases, thus the light-emitting layer is positioned further away from the reflective electrode 110b.

[0054] Figure 1The diagram illustrates an example where the first sub-pixel SP1 is a red sub-pixel and the second sub-pixel SP2 is a blue sub-pixel. The first sub-pixel SP1 includes a first emissive layer 153 configured to emit light with a longer wavelength, and the second sub-pixel SP2 includes a second emissive layer 151 configured to emit light with a shorter wavelength. No optical compensation layer is provided in the second sub-pixel SP2 configured to emit relatively shorter wavelength light; the optical distance of the second emissive layer 151 is maintained only by the first common layer CML on the second anode 110c'. A first optical compensation layer 122 is provided in the first sub-pixel SP1 configured to emit relatively longer wavelength light, thereby adjusting the longer optical distance between the first emissive layer 153 and the first reflective electrode 110b. The first emissive layer 153 can be a red emissive layer, and the second emissive layer 151 can be a blue emissive layer. The red emissive layer 153 can emit light with a wavelength range of 600 nm to 660 nm, and the blue emissive layer 151 can emit light with a wavelength range of 430 nm to 495 nm.

[0055] In the first sub-pixel SP1, the first optical compensation layer 122 is located between the first reflective electrode 110b and the first anode 110c, and can be formed of a transparent inorganic insulating film such as an oxide film, a nitride film, or a oxynitride film.

[0056] Transparent electrodes 110a and 110a' can be further disposed below the first reflective electrode 110b and the second reflective electrode 110b'. Therefore, the interfacial adhesion between the first reflective electrode 110b and the second reflective electrode 110b' and the thin-film transistor TFT disposed therebelow can be increased, and the contact resistance can be reduced.

[0057] The first reflective electrode 110b and the second reflective electrode 110b' are formed of reflective metal in order to increase the reflection efficiency in each sub-pixel SP1 and SP2. For example, the first reflective electrode 110b and the second reflective electrode 110b' may be formed of metal or metal alloy, such as Ag, Ag alloy, Al, Al alloy, Ag-Pb-Cu (APC), etc.

[0058] The first anode 110c and the second anode 110c' can be transparent electrodes formed of the same material as the transparent electrodes 110a and 110a'. In order to facilitate the transmission of light reflected by the first reflective electrode 110b and the second reflective electrode 110b' and to reduce the resistance at the interface between the first anode 110c and the second anode 110c' and the organic units OS1 and OS2 formed of organic materials, the first anode 110c and the second anode 110c' can be formed of a transparent oxide composition containing at least one of indium, tin and zinc.

[0059] From an electrical perspective, the vertical structure from the transparent electrodes 110a and 110a' to the cathode 160 is referred to as light-emitting devices OLED1 and OLED2. Furthermore, in light-emitting devices OLED1 or OLED2, the three-layer structure comprising the transparent electrode 110a or 110a', the reflective electrode 110b or 110b', and the anode 110c or 110c', which are subjected to the same electrical signal, can be referred to as an anode stack 1100A or 1100B. Figure 1 middle, Figure 3 The substrate 100 shown can be disposed below the light-emitting devices OLED1 and OLED2.

[0060] exist Figure 1 In the example shown, the first sub-pixel SP1 can be configured such that, in order to exhibit optical characteristics, a first optical compensation layer 122 is provided between the first reflective electrode 110b and the first anode 110c in the light-emitting portion, thus forming a vertical gap. However, in order to achieve conductivity, the first anode 110c and the first reflective electrode 110b or the first transparent electrode 110a extend from the first optical compensation layer 122 to one side in the non-light-emitting portion, thereby being directly electrically connected. Alternatively, a contact hole (not shown) can be formed through the first optical compensation layer 122, and the first anode 110c can be directly connected to the first reflective electrode 110b through the contact hole.

[0061] A capping layer 170 may be disposed commonly on the cathode 160 and distributed across all sub-pixels. The capping layer 170 may be configured to increase the luminous efficiency of light emitted by the light-emitting devices OLED1 and OLED2 and to protect the light-emitting devices OLED1 and OLED2. The capping layer 170 may have a two-layer structure, as shown in the figure, comprising an organic capping layer 171 and an inorganic capping layer 172 stacked on the organic capping layer 171, or an inverted structure of the two layers, or may have an organic / inorganic composite film structure. The capping layer 170 may be formed as a single layer. The organic material composition of the capping layer 170 may be the same as the organic material composition of the first unit OS1 and the second unit OS2.

[0062] The following will describe a light-emitting display device according to a second embodiment of the present invention, which, in addition to red and blue sub-pixels, further includes a green sub-pixel configured to emit light having an intermediate wavelength.

[0063] Figure 2 This is a cross-sectional view illustrating a light-emitting display device according to a second embodiment of the present invention. Figure 3 It is a diagram Figure 2 A detailed cross-sectional view of an example implementation of [the implementation name].

[0064] like Figure 2As shown, in addition to the red sub-pixel RS and the blue sub-pixel BS, the light-emitting display device according to the second embodiment of the present invention further includes a green sub-pixel GS as a third sub-pixel.

[0065] The green sub-pixel GS includes a third reflective electrode 110b”, a third anode 110c” disposed on the third reflective electrode 110b”, and a third unit OS3 (hereinafter, the third unit OS3 may also be referred to as the third organic stack OS3) disposed on the third anode 110c”. The third unit OS3 includes a first common layer CML, a third light-emitting layer 152 configured to emit green light or yellow-green light (which is light with a wavelength between red light and blue light), and a second common layer CMU 144. In addition, a cathode 160 may be further disposed on the third unit OS3.

[0066] In addition, a second optical compensation layer 121 with a thickness smaller than that of the first optical compensation layer 122 can be provided between the third reflective electrode 110b” and the third anode 110c”, thereby enabling the third light-emitting layer 152 to be located at the optimal light-emitting position of the third unit OS3.

[0067] Because the optical distance of green light (or yellow-green light) is shorter than that of red light, the vertical distance from the third reflective electrode 110b” to the third light-emitting layer 152 can be shorter than the vertical distance from the first reflective electrode 110b to the first light-emitting layer 153.

[0068] The first optical compensation layer 122 and the second optical compensation layer 121 can be formed to have different thicknesses using a halftone mask in the same process. The first optical compensation layer 122 and the second optical compensation layer 121 can be formed from the same transparent inorganic insulating film.

[0069] In the second embodiment, since the organic stacks OS1, OS2, and OS3 of each sub-pixel RS, BS, and GS, except for the corresponding light-emitting layers 153, 151, and 152, include the same common layers CML and CMU, the thickness difference between the organic stacks OS1, OS2, and OS3 is caused only by the thickness difference between the light-emitting layers 153, 151, and 152. In particular, in the second embodiment of the invention, the first optical compensation layer 122 and the second optical compensation layer 121 are disposed between the first reflective electrode 110b and the first anode 110c and between the third reflective electrode 110b” and the third anode 110c”, which can compensate for the optical distance of light of various colors. Since there is no large thickness difference between the organic stacks OS1, OS2, and OS3, the organic stacks OS1 and OS3 do not need to increase their thickness in the first sub-pixel SP1 and the third sub-pixel SP3 (red sub-pixel RS and green sub-pixel GS) having the first optical compensation layer 122 and the second optical compensation layer 121. Therefore, the driving voltage required to drive the organic stacks OS1 and OS3 between the anodes 110c and 110c” and the cathode 160 can be reduced. Furthermore, because it is formed with approximately to The first optical compensation layer 122 and the second optical compensation layer 121, which are of a certain thickness and disposed between the first reflective electrode 110b and the first anode 110c and between the third reflective electrode 110b” and the third anode 110c”, can be formed of inorganic materials, thus being insensitive to temperature. Therefore, compared with the structure in which the optical compensation layer is disposed in the organic unit, the structure having the first optical compensation layer 122 and the second optical compensation layer 121 can have higher film density and higher film stability.

[0070] Reference Figure 3 The structure of the light-emitting display device according to the present invention will now be described.

[0071] The construction of a thin-film transistor (TFT) will be described, wherein the TFT is connected to each of the first to third transparent electrodes 110a, 110a' and 110a” of the lower electrodes of the anode stacks 1100A, 1100B and 1100C, which are the first to third sub-pixels SP1, SP2 and SP3 (red, blue and green sub-pixels RS, BS and GS).

[0072] The assembly of substrate 100 and the thin-film transistor array formed on substrate 100 may be referred to as thin-film transistor substrate 1000.

[0073] Each of the sub-pixels RS, BS and GS may include at least one thin-film transistor TFT, the thin-film transistor TFT may include a gate electrode 102, an active layer 104 configured to overlap with the gate electrode 102, and a source electrode 106a and a drain electrode 106b connected to both sides of the active layer 104.

[0074] A channel protection layer 105 may be further disposed on the channel of the active layer 104 to protect the channel. A gate insulating film 103 may be further disposed between the gate electrode 102 and the active layer 104.

[0075] The active layer 104 may include at least one of an oxide semiconductor layer, a polycrystalline silicon layer, and an amorphous silicon layer.

[0076] Furthermore, the thin-film transistor substrate 1000 may include a first protective film 107 and a second protective film 108 to protect the thin-film transistor TFT. One of the first protective film 107 and the second protective film 108 may be an inorganic protective film, and the other may be an organic protective film.

[0077] The source electrode 106a can be connected to each of the anode stacks 1100A, 1100B and 1100C of the light-emitting devices OLED1, OLED2 and OLED3 through a contact hole CT formed through the first protective film 107 and the second protective film 108 to expose a portion of the source electrode 106a. Each of the three electrodes in the anode stacks 1100A, 1100B, and 1100C with a three-layer structure—namely, transparent electrodes 110a, 110a', or 110a”, reflective electrodes 110b, 110b', or 110b”, and anodes 110c, 110c', or 110c”—is electrically connected. However, there is a difference between the layer structure of the first sub-pixel SP1 and the third sub-pixel SP3 (red sub-pixel RS and green sub-pixel GS) with optical compensation layers 122 and 121 between the reflective electrodes 110b and 110b” and the anodes 110c and 110c”, and the layer structure of the second sub-pixel SP2 (blue sub-pixel BS) without an optical compensation layer.

[0078] The edge of each of the anode stacks 1100A, 1100B, and 1100C overlaps with the embankment 130, and the portion of each of the anode stacks 1100A, 1100B, and 1100C exposed from the embankment 130 is defined as a light-emitting portion. The portion of each of the sub-pixels RS, GS, and BS that is disposed of with the embankment 130 is defined as a non-light-emitting portion.

[0079] In the second sub-pixel SP2 (blue sub-pixel BS) without an optical compensation layer, the second transparent electrode 110a', the second reflective electrode 110b', and the second anode 110c' are sequentially stacked to form a second anode stack 1100B. These layers, as electrode components, are directly and electrically connected. The second transparent electrode 110a' and / or the second reflective electrode 110b' can be connected to the source electrode 106a of the thin-film transistor TFT disposed below it.

[0080] In the first sub-pixel SP1 (red sub-pixel RS), particularly in the light-emitting portion exposed from the embankment 130, the first transparent electrode 110a, the first reflective electrode 110b, the first optical compensation layer 122, and the first anode 110c are sequentially stacked. Therefore, the first optical compensation layer 122 is used to increase the optical distance from the upper surface of the first reflective electrode 110b. Furthermore, in the portion of the first sub-pixel SP1 (red sub-pixel RS) overlapping the embankment 130, i.e., the non-light-emitting portion, the first anode 110c can be connected along the side of the first optical compensation layer 122 to the exposed portion of the first reflective electrode 110b disposed below it, and the same electrical signal can be applied to the first transparent electrode 110a, the first reflective electrode 110b, and the first anode 110c. Additionally, in the non-light-emitting portion, the first transparent electrode 110a and / or the first reflective electrode 110b can be connected to the source electrode 106a of the thin-film transistor TFT disposed below it.

[0081] Similarly, in the third sub-pixel SP3 (green sub-pixel GS), particularly in the light-emitting portion exposed from the embankment 130, the third transparent electrode 110a”, the third reflective electrode 110b”, the second optical compensation layer 121, and the third anode 110c” are stacked sequentially. Therefore, the second optical compensation layer 121 is used to increase the optical distance from the upper surface of the third reflective electrode 110b”. The third sub-pixel SP3 (green sub-pixel GS) emits light with a wavelength shorter than that emitted by the first sub-pixel SP1 (red sub-pixel RS), and therefore requires a shorter optical distance than the first sub-pixel SP1 (red sub-pixel RS). Thus, the thickness of the second optical compensation layer 121 can be less than the thickness of the first optical compensation layer 122.

[0082] Furthermore, in the portion of the third sub-pixel SP3 (green sub-pixel GS) that overlaps with the embankment 130, i.e., in the non-light-emitting portion, the third anode 110c” can be connected along the side of the second optical compensation layer 121 to the exposed portion of the third reflective electrode 110b” disposed below it, and the same electrical signal can be applied to the third transparent electrode 110a”, the third reflective electrode 110b”, and the third anode 110c”. Additionally, in the non-light-emitting portion, the third transparent electrode 110a” and / or the third reflective electrode 110b” can be connected to the source electrode 106a of the thin-film transistor TFT disposed below it.

[0083] A capping layer 170 can be provided on the cathode 160 to increase the luminous efficiency of the light emitted by the light-emitting devices OLED1, OLED2, and OLED3 and to protect the light-emitting devices OLED1, OLED2, and OLED3. Furthermore, an encapsulation layer 190 can be further provided on the capping layer 170 to prevent moisture from flowing into the light-emitting devices OLED1, OLED2, and OLED3 and to prevent the influence of ambient air. In addition to the encapsulation layer 190, a color filter layer, a polarizing layer, or other optical films can also be additionally provided. Furthermore, the encapsulation layer 190 can be configured as an encapsulation film structure in which organic and inorganic films are alternately stacked, or an encapsulation substrate and an adhesive layer disposed between the array including the light-emitting devices OLED1, OLED2, and OLED3 and the encapsulation substrate can be further provided.

[0084] Hereinafter, a light-emitting display device according to another embodiment of the present invention will be described, which further includes an auxiliary optical compensation layer disposed in an organic stack between an anode and a cathode.

[0085] Figure 4 This is a cross-sectional view illustrating a light-emitting display device according to a third embodiment of the present invention. Figure 5 It is a diagram Figure 4 A detailed cross-sectional view of an example implementation of [the implementation name].

[0086] In light-emitting display devices, because multiple organic films are stacked on the anode instead of a single organic film and each sub-pixel has a different light-emitting layer, the sub-pixels exhibit different distribution characteristics, thus requiring compensation.

[0087] Because the aforementioned optical compensation layer is formed before the anodes 110c, 110c' and 110c” are formed, and the anodes 110c, 110c' and 110c” are located before the organic layer, it is difficult to substantially use the optical compensation layer as a compensation method in the organic deposition process.

[0088] In addition to the optical compensation layer located between the reflective electrode and the anode to adjust the optical distance, the following will describe an auxiliary optical compensation layer configured to finely adjust the differences in process distribution within the chamber.

[0089] like Figure 4 and Figure 5As shown, the light-emitting display device according to the third embodiment of the present invention includes: a substrate 200 having a red sub-pixel RS, a blue sub-pixel BS, and a green sub-pixel GS; a first reflective electrode 210b, a second reflective electrode 210b', and a third reflective electrode 210b" respectively disposed in the red sub-pixel RS, the blue sub-pixel BS, and the green sub-pixel GS; a first optical compensation layer 222 disposed on the first reflective electrode 210b; a second optical compensation layer 221 disposed on the third reflective electrode 210b"; a first anode 210c disposed in contact with the upper surface of the first optical compensation layer 222; a second anode 210c' disposed in contact with the upper surface of the second reflective electrode 210b'; and a third anode 210c" disposed in contact with the upper surface of the second optical compensation layer 221. Furthermore, the light-emitting display device according to the third embodiment of the present invention is characterized in that a first auxiliary optical compensation layer 282 and a second auxiliary optical compensation layer 281 (also described as "AUX R'" and "AUX G'" in the figures) are respectively disposed in the red sub-pixel RS and the green sub-pixel GS.

[0090] When the thickness of the organic stacks OS1, OS2, and OS3 needs to be adjusted according to differences in equipment or process distribution, a first auxiliary optical compensation layer 282 and a second auxiliary optical compensation layer 281 according to the present invention are provided. The required thickness of the organic stacks for compensation is calculated before each process in the chamber, and then the first auxiliary optical compensation layer 282 and the second auxiliary optical compensation layer 281 are formed. Therefore, the first auxiliary optical compensation layer 282 and the second auxiliary optical compensation layer 281 are very thin, thereby achieving fine compensation, and the respective thicknesses of the first auxiliary optical compensation layer 282 and the second auxiliary optical compensation layer 281 are less than the thicknesses of the adjacent corresponding light-emitting layers 253 and 252 and less than or equal to 0.22 times the thickness of the first optical compensation layer 222. Furthermore, because the first auxiliary optical compensation layer 282 and the second auxiliary optical compensation layer 281 are very small in thickness compared to the first auxiliary optical compensation layer 282, the increase in the thickness of the organic stacks OS1, OS2, and OS3 is very small, and therefore the change in driving voltage is not significant compared to the first and second embodiments.

[0091] Each of the first auxiliary optical compensation layer 282 and the second auxiliary optical compensation layer 281 can be formed in the same chamber used to form one of the corresponding light-emitting layers in the first light-emitting layer 253 and the second light-emitting layer 252. The first auxiliary optical compensation layer 282 can be formed with the same substrate as the first light-emitting layer 253, and the second auxiliary optical compensation layer 281 can be formed with the same substrate as the third light-emitting layer 252. In some cases, the first auxiliary optical compensation layer 282 and the second auxiliary optical compensation layer 281 can be formed of hole transport material. A receiving part can be provided to selectively provide hole transport material to the interior of the chamber used to form the light-emitting layer, and the hole transport material in the receiving part can be provided to the red sub-pixel RS and the green sub-pixel GS on the substrate 200 before the formation of the first light-emitting layer 253 and the second light-emitting layer 252.

[0092] The structure of the red subpixel RS will now be described in detail.

[0093] The first reflective electrode 210b can be disposed on the first transparent electrode 210a, thereby reducing the interface resistance when the first transparent electrode 210a is connected to the thin-film transistor TFT disposed below it. Furthermore, a first optical compensation layer 222 can be disposed on the first reflective electrode 210b, thereby adjusting the optical distance of the longer wavelength light in the red sub-pixel RS. Additionally, a first anode 210c can be disposed on the first optical compensation layer 222. In the non-light-emitting portion of the red sub-pixel RS, a first anode stack 2100A can be formed by conductively connecting and sequentially stacking the first transparent electrode 210a, the first reflective electrode 210b, and the first anode 210c.

[0094] Furthermore, a first organic stack OS1 is provided, comprising a first common layer CML, a first auxiliary optical compensation layer 282, a first light-emitting layer 253 configured to emit light having a first wavelength, and a second common layer CMU 244, sequentially stacked on the first anode 210c. Additionally, a cathode 260 and a capping layer 270 may be further stacked on the first organic stack OS1. The capping layer 270 may have a stacked structure including a first capping layer 271 and a second capping layer 272, the first capping layer 271 and the second capping layer 272 having different refractive indices.

[0095] In addition, the first common layer CML may include a hole injection layer 241 and a hole transport layer 242 involving hole injection and transport, as well as an electron blocking layer 243.

[0096] The hole injection layer 241 is formed of a material having a low energy barrier and low surface resistance to the first anode 210c, so that holes from the first anode 210c can be easily injected into the hole injection layer 241. For this purpose, the material of the hole injection layer 241 may include p-type dopants in the hole transport material.

[0097] Hole transport layer 242 can easily transport holes provided by hole injection layer 241 to first light-emitting layer 253, and hole transport layer 242 is formed of hole transport material.

[0098] The electron blocking layer 243 is used to prevent excitons formed by the first light-emitting layer 253 or electrons transported to the first light-emitting layer 253 from moving to the hole transport layer 242.

[0099] In some cases, the hole injection layer 241 and the electron blocking layer 243 may be omitted, or they may be integrally formed with the hole transport layer 242.

[0100] The second common layer CMU 244 may include: a hole blocking layer HBL configured to prevent holes from escaping the first light-emitting layer 253; and an electron transport layer ETL configured to transport electrons. The hole blocking layer HBL and the electron transport layer ETL may be formed as different layers. The hole blocking layer HBL and the electron transport layer ETL may be formed separately.

[0101] Depending on the performance requirements of the display device, the first common layer CML and the second common layer CMU may further include additional layers integral with them, and may include the matrix and dopant components contained in the first light-emitting layer 253.

[0102] In the red, blue, and green sub-pixels RS, BS, and GS, in the structure disposed on the first to third anodes 210c, 210c', and 210c", the aforementioned first common layer CML, second common layer CMU 144, cathode 260, and capping layer 270 are identical in the red, blue, and green sub-pixels RS, BS, and GS. They can be formed using a common mask instead of a fine metal mask and are commonly disposed in all sub-pixels RS, BS, and GS. That is, even in the non-light-emitting portion on the embankment 230, the first common layer CML, second common layer CMU 144, cathode 260, and capping layer 270 are integrally disposed without separation.

[0103] The difference between the blue sub-pixel BS and the red sub-pixel RS is that no optical compensation layer is provided below the second anode 210c' and no auxiliary optical compensation layer is provided in the second organic stack OS2. Because the blue sub-pixel BS does not have an optical compensation layer and an auxiliary optical compensation layer, the distance from the second reflective electrode 210b' to the second light-emitting layer 251 is shorter than the distance in the red sub-pixel RS.

[0104] Furthermore, the green sub-pixel GS differs from the red sub-pixel RS in that a second optical compensation layer 221 with a thickness smaller than that of the first optical compensation layer 222 is provided below the third anode 210c”, and a second auxiliary optical compensation layer 281 is provided in the third organic stack OS3.

[0105] Each of the light-emitting layers 253, 251, and 252 includes a matrix and a dopant. Each of the light-emitting layers 253, 251, and 252 includes a dopant to emit light of a specific color, and each of the light-emitting layers 253, 251, and 252 includes a matrix to assist in the excitation of the dopant. Because the dopants of the light-emitting layers 253, 251, and 252 are different, the matrix configured to assist in the excitation of the dopant is also different depending on the color of the light emitted by the light-emitting layers 253, 251, and 252. Therefore, the first auxiliary optical compensation layer 282 and the second auxiliary optical compensation layer 281, formed from the same matrix as the matrix in the adjacent light-emitting layers 253 and 252, can be formed from different materials in different processes.

[0106] The green sub-pixel GS includes a second optical compensation layer 221 with a thickness smaller than that of the first optical compensation layer 222, and the distance from the third reflective electrode 210b” to the third light-emitting layer 252 is shorter than that in the red sub-pixel RS.

[0107] Reference Figure 5 A thin-film transistor array substrate 2000 according to a third embodiment of the present invention will be briefly described.

[0108] In the thin-film transistor array substrate 2000, each of the sub-pixels RS, BS and GS may include at least one thin-film transistor TFT. The thin-film transistor TFT may include a gate electrode 202, an active layer 204 configured to overlap with the gate electrode 202, and a source electrode 206a and a drain electrode 206b connected to both sides of the active layer 204.

[0109] A channel protection layer 205 can be further disposed on the channel of the active layer 204 to protect the channel. A gate insulating film 203 can be further disposed between the gate electrode 202 and the active layer 204.

[0110] The active layer 204 may include at least one of an oxide semiconductor layer, a polycrystalline silicon layer, and an amorphous silicon layer.

[0111] Furthermore, the thin-film transistor substrate 2000 may include a first protective film 207 and a second protective film 208 to protect the thin-film transistor TFT. The TFT can be connected to each of the first to third anode stacks 2100A, 2100B and 2100C of the respective light-emitting devices through contact holes formed through the first protective film 207 and the second protective film 208 to expose a portion of the source electrode 206a.

[0112] The embankment 230 can be configured to open the light-emitting portions of each sub-pixel RS, BS and GS, and the embankment 230 can overlap with the edges of the first to third anode stacks 2100A, 2100B and 2100C.

[0113] As described above, a first organic stack OS1 including a first auxiliary optical compensation layer 282 and a first light-emitting layer 253, a second organic stack OS2 having a second light-emitting layer 251, and a third organic stack OS3 including a second auxiliary optical compensation layer 281 and a third light-emitting layer 252 are disposed on the first to third anode stacks 2100A, 2100B and 2100C.

[0114] The first to third organic stacks OS1, OS2, and OS3 commonly include a first common layer CML on the first to third anodes 210c, 210c', and 210c" of each anode stack 2100A, 2100B, and 2100C. The first organic stack OS1 and the third organic stack OS3 in the red sub-pixel RS and the green sub-pixel GS include a first light-emitting layer 253 and a third light-emitting layer 252 configured to contact the first auxiliary optical compensation layer 282 and the second auxiliary optical compensation layer 281 on the first common layer CML. In the blue sub-pixel BS, the second light-emitting layer 251 is directly disposed on the first common layer CML. The second common layer CMU is disposed on each of the light-emitting layers 253, 252, and 251.

[0115] The cathode 260 and the capping layer 270 are sequentially disposed on each organic stack OS1, OS2 and OS3.

[0116] In addition, an encapsulation layer 290 can be further provided on the cover layer 170 to prevent moisture from flowing into the light-emitting device and to prevent the influence of ambient air.

[0117] The following section will describe an example of applying a structure consisting of multiple stacked bodies to each subpixel.

[0118] Figures 6 to 11 This is a cross-sectional view illustrating a light-emitting display device according to the fourth to ninth embodiments of the present invention.

[0119] like Figure 6As shown, the light-emitting display device according to the fourth embodiment of the present invention includes a first stack S1 and a second stack S2 on the anodes 310c, 310c', and 310c" in each of the sub-pixels RS, BS, and GS, wherein a charge generation layer 360 is inserted between the first stack S1 and the second stack S2. Furthermore, the light-emitting display device according to the fourth embodiment of the present invention has a structure in which an optical compensation layer 321 is provided between the reflective electrode 310b and the anode 310c in the red sub-pixel RS where the longest optical distance is required. A transparent electrode 310a may be provided below the reflective electrode 310b.

[0120] In the fourth embodiment shown in the figure, the optical compensation layer 321 is only disposed in the red sub-pixel RS, and the blue sub-pixel BS and the green sub-pixel GS have a common three-layer structure including one of the anodes 310c' and 310c" respectively, a transparent electrode 310a and a reflective electrode 310b.

[0121] The charge generation layer 360 may include, for example, an n-type charge generation layer 361 configured to facilitate electron generation and assist in electron transport from the lower stack; and a p-type charge generation layer 362 configured to facilitate hole generation and assist in hole transport to the upper stack. The charge generation layer 360 may be formed as a structure comprising multiple layers, or may be formed as a single layer comprising n-type and p-type dopants in a matrix material.

[0122] The first stack body S1 may include a first common layer CML1, a light-emitting layer 353, 351 or 352, and a second common layer CMU1.

[0123] With Figure 1 In the same manner as the first common layer CML shown, the first common layer CML1 may include a hole injection layer 341 and a first hole transport layer 342.

[0124] As shown in the figure, a first electron blocking layer 343 can be further disposed in the blue sub-pixel BS. In this case, the first electron blocking layer 343 can be formed from a material different from that of the second light-emitting layer 351, using the same fine metal mask (FMM) process as the second light-emitting layer 351 used to form the first stack S1. In the structure shown having multiple stacks S1 and S2, the optical compensation layer 321 below the anode 310c can adjust the optical distance in the red sub-pixel RS that emits light with the longest wavelength, thus adjusting the difference in optical distance between the red sub-pixel RS and the green sub-pixel GS that emits light with an intermediate wavelength. In this structure, the green sub-pixel GS does not have an optical compensation layer. To adjust the difference in optical distance between the green sub-pixel GS and the blue sub-pixel BS that emits light with a shorter wavelength, the optical distance in the blue sub-pixel BS is adjusted by reducing the thickness of the second light-emitting layer 351 to be less than the thickness of the light-emitting layers of the other sub-pixels RS and GS.

[0125] In this case, during the driving of the corresponding light-emitting device, excitons or electrons generated from the second light-emitting layer 351, which has a smaller thickness, tend to escape to the first common layer CML1 disposed below it, compared to the first light-emitting layer 353 or the third light-emitting layer 352, which has a relatively large thickness. To prevent this problem, the light-emitting display device according to the fourth embodiment of the present invention further includes a first electron blocking layer 343 disposed below the second light-emitting layer 351.

[0126] The second common layer CMU1 disposed on each of the light-emitting layers 353, 351 and 352 in each of the first stack bodies S1 may include a first hole blocking layer 344 and a first electron transport layer 345.

[0127] The second stack S2 may include a third common layer CML2, a light-emitting layer 383, 381 or 382, ​​and a fourth common layer CMU2 on the charge generation layer 360 in one of the respective sub-pixels RS, BS and GS.

[0128] The third common layer CML2 may include the second hole transport layer 371.

[0129] Similar to the first stack S1 described above, a second electron blocking layer 372 can be further provided in the second stack S2 of the blue sub-pixel BS. In this case, in order to prevent excitons or electrons generated from the second light-emitting layer 381 of the second stack S2 from easily escaping to the third common layer CML2 disposed below it due to the small thickness of the second light-emitting layer 381, a second electron blocking layer 372 with a small thickness is further provided below the second light-emitting layer 381 of the second stack S2.

[0130] The fourth common layer CMU2 disposed on each of the light-emitting layers 383, 381 and 382 in each of the second stack bodies S2 may include a second hole blocking layer 373 and a second electron transport layer 374.

[0131] The cathode 390 and the capping layer 395 can be sequentially disposed on the second stack S2.

[0132] Although the illustrated example shows a two-layer structure, this disclosure is not limited thereto, and examples are possible in which another charge-generating layer is disposed on the second stack body S2, and an additional stack body having a structure of the second stack body is additionally disposed on the charge-generating layer. That is, a structure comprising three or more stack bodies and charge-generating layers disposed between the respective stack bodies can be realized.

[0133] The structure with multiple stacked volumes improves the luminous efficiency of light emitted from each sub-pixel for each color, thus enabling clear colors and high efficiency.

[0134] like Figure 7 As shown, the light-emitting display device according to the fifth embodiment of the present invention is similar to the light-emitting display device according to the fourth embodiment in that each of the sub-pixels RS, BS and GS has a structure including multiple stacks and an optical compensation layer 421 is provided between the reflective electrode 410b and the anode 410c in the red sub-pixel RS. However, it differs from the light-emitting display device according to the fourth embodiment in that a first auxiliary optical compensation layer 450 and a second auxiliary optical compensation layer 480 (also described as “AUX R'1” and “AUX R'2” in the figure) are additionally provided in the first stack S1 and the second stack S2 in the red sub-pixel RS.

[0135] Since the light-emitting display device according to the fifth embodiment differs from the light-emitting display device according to the fourth embodiment in that the red sub-pixel RS has a stacked structure, the structure of the red sub-pixel RS will be described below.

[0136] In the red sub-pixel RS, an optical compensation layer 421 can be provided between the reflective electrode 410b and the anode 410c. Therefore, the positions of the first red light-emitting layer 453 and the second red light-emitting layer 483 of the first stack S1 and the second stack S2 can be adjusted upwards. A transparent electrode 410a is provided below the reflective electrode 410b, and the blue sub-pixel BS and the green sub-pixel GS can share a structure in which one of the transparent electrode 410a, the reflective electrode 410b, and the anodes 410c' and 410c" are stacked.

[0137] In the red sub-pixel RS, the first stack body S1 may include a first common layer CML1, a first auxiliary optical compensation layer 450, a first red emitting layer 453, and a second common layer CMU1.

[0138] With Figure 1 In the same manner as the first common layer CML shown, the first common layer CML1 may include a hole injection layer 441 and a first hole transport layer 442.

[0139] A first auxiliary optical compensation layer 450 is provided to compensate for minor distribution deviations between the device and sub-pixels during the process of stacking organic layers after the formation of the anode 410c, and the first auxiliary optical compensation layer 450 is formed to have a thickness smaller than that of the optical compensation layer 421 configured to primarily adjust the optical distance. The thickness of the first auxiliary optical compensation layer 450 is less than or equal to 0.22 times the thickness of the optical compensation layer 421. In particular, the thickness of the first auxiliary optical compensation layer 450 can be selected within a range that can compensate for distribution characteristics without increasing the driving voltage. The first auxiliary optical compensation layer 450 can be formed using the same mask in the same chamber as the first red emitting layer 453, and can be formed from the same material as the red matrix used to form the first red emitting layer 453. That is, the first auxiliary optical compensation layer 450 is formed by depositing a smaller thickness of red matrix material before the formation of the first red emitting layer 453.

[0140] The first common layer CML1 of the first stack S1 is commonly disposed in the red sub-pixel RS, the blue sub-pixel BS, and the green sub-pixel GS.

[0141] As shown in the figure, a first electron blocking layer 443 may be further disposed in the blue sub-pixel BS. The first electron blocking layer 443 is the same as the first electron blocking layer 343 described above, and therefore its detailed description will be omitted.

[0142] Furthermore, a second common layer CMU1 is disposed on each of the first red light-emitting layer 453, the first blue light-emitting layer 451, and the first green light-emitting layer 452 of each of the first stacks S1. The second common layer CMU1 may include a first hole-blocking layer 444 and a first electron transport layer 445.

[0143] The charge generation layer 460 may include, for example, an n-type charge generation layer 461 configured to facilitate electron generation and assist in the transfer of electrons from the lower stack; and a p-type charge generation layer 462 configured to facilitate hole generation and assist in the transfer of holes to the upper stack.

[0144] The second stack S2 may include a third common layer CML2, a light-emitting layer 483, 481 or 482, and a fourth common layer CMU2 on the charge generation layer 460 in one of the respective sub-pixels RS, BS and GS.

[0145] The third common layer CML2 may include a second hole transport layer 471, and the fourth common layer CMU2 may include a second hole blocking layer 473 and a second electron transport layer 474.

[0146] Furthermore, as described above, a second auxiliary optical compensation layer 480 may be further disposed between the third common layer CML2 of the second stack S2 in the red sub-pixel RS and the second red emitting layer 483, and a second electron blocking layer 472 may be further disposed between the third common layer CML2 of the second stack S2 in the blue sub-pixel BS and the second blue emitting layer 481.

[0147] Compared with the light-emitting display device according to the fourth embodiment, the light-emitting display device according to the fifth embodiment includes auxiliary optical compensation layers 450 and 480 in the organic stacks S1 and S2 of the sub-pixels having optical compensation layer 421, thereby enabling adjustment of subtle distribution deviations between the device and the sub-pixels.

[0148] The cathode 490 and the capping layer 495 can be sequentially disposed on the second stack S2.

[0149] Figure 8 The light-emitting display device according to the sixth embodiment of the present invention differs from the light-emitting display device according to the fifth embodiment in that an auxiliary optical compensation layer 550 is provided only in the first stacked body S1 of the red sub-pixel RS. The auxiliary optical compensation layer 550 is provided on the first common layer CML1 in the first stacked body S1, and then a first red light-emitting layer 553 is formed on the auxiliary optical compensation layer 550. Furthermore, in the red sub-pixel RS, an optical compensation layer 521 is provided between the reflective electrode 510b and the anode 510c.

[0150] Figure 9 The light-emitting display device shown according to the seventh embodiment of the present invention differs from the light-emitting display device according to the fifth embodiment in that an auxiliary optical compensation layer 580 is provided only in the second stack S2 of the red sub-pixel RS. The auxiliary optical compensation layer 580 is provided on the third common layer CML2 in the second stack S2, and then a second red light-emitting layer 583 is formed on the auxiliary optical compensation layer 580. Furthermore, in the red sub-pixel RS, an optical compensation layer 521 is provided between the reflective electrode 510b and the anode 510c.

[0151] Figure 8 and Figure 9The structure of the light-emitting display device shown is the same as that of the light-emitting display device according to the fifth embodiment described above, except that an auxiliary optical compensation layer 550 or 580 is selectively provided in the first stack S1 or the second stack S2 between the anode 510c and the cathode 590 in the red sub-pixel RS. Therefore, the various layers not described above will be briefly described.

[0152] First, the following description will be given based on the red subpixel RS.

[0153] The first common layer CML1 is disposed below the auxiliary optical compensation layer 550 and the first red light-emitting layer 553 stacked on the auxiliary optical compensation layer 550 of the first stack body S1, and the first common layer CML1 of the first stack body S1 includes a hole injection layer 541 and a first hole transport layer 542.

[0154] A second common layer CMU1, formed by stacking a first hole blocking layer 544 and a first electron transport layer 545, is disposed on the first red emitting layer 553.

[0155] The third common layer CML2 is disposed below the second red emitting layer 583 of the second stack body S2, and the third common layer CML2 includes the second hole transport layer 571.

[0156] A fourth common layer CMU2, formed by stacking a second hole blocking layer 573 and a second electron transport layer 574, is disposed on the second red luminescent layer 583.

[0157] Common layers CML1, CMU1, CML2, and CMU2, charge generation layer 560, cathode 590, and capping layer 595 are commonly disposed in each sub-pixel RS, BS, and GS. Furthermore, in each sub-pixel RS, BS, and GS, a transparent electrode 510a is disposed below the reflective electrode 510b. Although an optical compensation layer 521 is disposed on the reflective electrode 510b in the red sub-pixel RS, anodes 510c' and 510c" are directly disposed on the reflective electrode 510b in the blue sub-pixel BS and the green sub-pixel GS.

[0158] The blue sub-pixel BS may further include electron blocking layers 543 and 572 to prevent electrons or excitons generated from the first blue emitting layer 551 and the second blue emitting layer 581, which have a smaller thickness, from moving toward the first common layer CML1 and the third common layer CML2 disposed below them.

[0159] like Figure 10As shown, the light-emitting display device according to the eighth embodiment of the present invention differs from the light-emitting display device according to the fifth embodiment in that optical compensation layers 622 and 621 and auxiliary optical compensation layers 650a, 680a, 650b and 680b (in the figure, 650b and 680b are also described as “AUX G'1” and “AUX G'2”) are provided in the respective stacks S1 and S2 of the red sub-pixel RS and the green sub-pixel GS.

[0160] Specifically, in the red sub-pixel RS, a first optical compensation layer 622 can be provided between the reflective electrode 610b and the anode 610c, so that the positions of the first red light-emitting layer 653 and the second red light-emitting layer 683 of the first stack S1 and the second stack S2 can be adjusted upward.

[0161] Furthermore, in the green sub-pixel GS, a second optical compensation layer 621 can be provided between the reflective electrode 610b and the anode 610c”, so that the positions of the first green light-emitting layer 652 and the second green light-emitting layer 682 of the first stack S1 and the second stack S2 can be adjusted upward.

[0162] The transparent electrode 610a is commonly disposed below the reflective electrode 610b in each sub-pixel RS, BS and GS.

[0163] In this case, the blue sub-pixel BS has a three-layer stacked structure including a transparent electrode 610a, a reflective electrode 610b, and an anode 610c', and these electrodes 610a, 610b, and 610c' are electrically connected.

[0164] The first stack S1 in the red sub-pixel RS may include a first common layer CML1, a first auxiliary optical compensation layer 650a, a first red emitting layer 653, and a second common layer CMU1. The first stack S1 in the blue sub-pixel BS may include a first common layer CML1, a first blue emitting layer 651, and a second common layer CMU1. The first stack S1 in the green sub-pixel GS may include a first common layer CML1, a second auxiliary optical compensation layer 650b, a first green emitting layer 652, and a second common layer CMU1.

[0165] With Figure 1 In the same manner as the first common layer CML shown, the first common layer CML1 may include a hole injection layer 641 and a first hole transport layer 642.

[0166] A first auxiliary optical compensation layer 650a and a second auxiliary optical compensation layer 650b are provided to compensate for minor distribution deviations between the device and sub-pixels during the process of stacking organic layers after the formation of the anode 610c. The first and second auxiliary optical compensation layers 650a and 650b are formed to have a thickness smaller than that of the first optical compensation layer 622 and the second optical compensation layer 621, which are configured to primarily adjust the optical distance. The thickness of the first and second auxiliary optical compensation layers 650a and 650b is less than or equal to 0.22 times the thickness of the first and second optical compensation layers 622 and 621. In particular, the thicknesses of the first and second auxiliary optical compensation layers 650a and 650b can be selected within a range that allows for compensation of distribution characteristics without increasing the driving voltage. The first and second auxiliary optical compensation layers 650a and 650b can be formed using the same mask in the same chamber as the first red emitting layer 653 and the first green emitting layer 652, respectively. The first auxiliary optical compensation layer 650a may be formed of the same material as the red matrix used to form the first red emitting layer 653, and the second auxiliary optical compensation layer 650b may be formed of the same material as the green matrix used to form the first green emitting layer 652. That is, before forming the first red emitting layer 653 and the first green emitting layer 652, the first auxiliary optical compensation layer 650a is formed by depositing a small thickness of red matrix material, and the second auxiliary optical compensation layer 650b is formed by depositing a small thickness of green matrix material.

[0167] As shown in the figure, a first electron blocking layer 643 may be further disposed in the blue sub-pixel BS. The first electron blocking layer 643 is the same as the first electron blocking layer 343 described above, and therefore its detailed description will be omitted.

[0168] Furthermore, a second common layer CMU1 is disposed on each of the first red emitting layer 653, the first blue emitting layer 651, and the first green emitting layer 652 of the first stack S1 in each of the sub-pixels RS, BS, and GS. The second common layer CMU1 may include a first hole blocking layer 644 and a first electron transport layer 645.

[0169] The charge generation layer 660 may include, for example, an n-type charge generation layer 661 configured to facilitate electron generation and assist in the transfer of electrons from the lower stack; and a p-type charge generation layer 662 configured to facilitate hole generation and assist in the transfer of holes to the upper stack.

[0170] The second stack S2 may include a third common layer CML2, a light-emitting layer 683, 681 or 682, and a fourth common layer CMU2 on the charge generation layer 660 in one of the respective sub-pixels RS, BS and GS.

[0171] The third common layer CML2 may include a second hole transport layer 671, and the fourth common layer CMU2 may include a second hole blocking layer 673 and a second electron transport layer 674.

[0172] Furthermore, a third auxiliary optical compensation layer 680a may be further provided between the third common layer CML2 of the second stack S2 in the red sub-pixel RS and the second red light-emitting layer 683; a second electron blocking layer 672 may be further provided between the third common layer CML2 of the second stack S2 in the blue sub-pixel BS and the second blue light-emitting layer 681; and a fourth auxiliary optical compensation layer 680b may be further provided between the third common layer CML2 of the second stack S2 in the green sub-pixel GS and the second green light-emitting layer 682.

[0173] Compared to the light-emitting display device according to the fourth embodiment, in addition to applying compensation structures such as an optical compensation layer and an auxiliary optical compensation layer to the green sub-pixel GS that emits light with a longer wavelength to the red sub-pixel RS, the light-emitting display device according to the eighth embodiment also applies compensation structures such as an optical compensation layer and an auxiliary optical compensation layer to the green sub-pixel GS that emits light with an intermediate wavelength, thereby enabling adjustment of the optical distance and finer adjustment of the subtle distribution deviation between the device and the sub-pixel.

[0174] The cathode 690 and the capping layer 695 can be sequentially disposed on the second stack S2.

[0175] like Figure 11 As shown, the light-emitting display device according to the ninth embodiment of the present invention has the same structure as the light-emitting display device according to the eighth embodiment, except that an auxiliary optical compensation layer is not provided in the second stack body S2 of the red sub-pixel RS.

[0176] The layers not described above will be briefly described.

[0177] First, the following description will be given based on the red subpixel RS.

[0178] The first optical compensation layer 722 is disposed between the reflective electrode 710b and the anode 710c.

[0179] Furthermore, the first common layer CML1 is disposed below the first auxiliary optical compensation layer 750a and the first red light-emitting layer 753 stacked on the first auxiliary optical compensation layer 750a of the first stack body S1, and the first common layer CML1 of the first stack body S1 includes a hole injection layer 741 and a first hole transport layer 742.

[0180] A second common layer CMU1, formed by stacking a first hole blocking layer 744 and a first electron transport layer 745, is disposed on the first red emitting layer 753.

[0181] The third common layer CML2 is disposed below the second red emitting layer 783 of the second stack body S2, and the third common layer CML2 includes the second hole transport layer 771.

[0182] A fourth common layer CMU2, formed by stacking a second hole blocking layer 773 and a second electron transport layer 774, is disposed on the second red luminescent layer 783.

[0183] Common layers CML1, CMU1, CML2, and CMU2, charge generation layer 760, cathode 790, and capping layer 795 are commonly disposed in each sub-pixel RS, BS, and GS. Furthermore, in each sub-pixel RS, BS, and GS, a transparent electrode 710a is disposed below the reflective electrode 710b. Although a first optical compensation layer 722 is disposed on the reflective electrode 710b in the red sub-pixel RS, the anode 710c' is directly disposed on the reflective electrode 710b in the blue sub-pixel BS. Furthermore, a second optical compensation layer 721 having a thickness smaller than that of the first optical compensation layer 722 is disposed on the reflective electrode 710b in the green sub-pixel GS.

[0184] The blue sub-pixel BS may further include electron blocking layers 743 and 772 to prevent electrons or excitons generated from the first blue emitting layer 751 and the second blue emitting layer 781, which have a smaller thickness, from moving toward the first common layer CML1 and the third common layer CML2 disposed below them.

[0185] In addition, the green sub-pixel GS includes a second auxiliary optical compensation layer 750b and a third auxiliary optical compensation layer 780 in the first stack S1 and the second stack S2.

[0186] In this case, the second auxiliary optical compensation layer 750b and the third auxiliary optical compensation layer 780 can be formed by providing a matrix for forming the green light-emitting layer before forming the first green light-emitting layer 752 and the second green light-emitting layer 782 adjacent to the second auxiliary optical compensation layer 750b and the third auxiliary optical compensation layer 780.

[0187] Although the above embodiments describe a two-layer structure, the light-emitting display device according to the present invention is not limited to a two-layer structure. The construction of the light-emitting display device according to the present invention can be applied to structures comprising three or more stacked bodies, or to structures in which the number of stacked bodies differs among red, green, and blue light-emitting devices. The light-emitting display device according to the present invention is characterized in that an optical compensation layer for adjusting the optical distance of the light-emitting layer of each stacked body is located between the reflective electrode and the anode, and an auxiliary optical compensation layer configured to achieve fine adjustment can be additionally provided in the organic stacked body. In the structure having the above-described optical compensation layer, the auxiliary optical compensation layer can be provided in each of the stacked bodies, or in some of the stacked bodies. Furthermore, the auxiliary optical compensation layer can be provided in all sub-pixels having the optical compensation layer, or selectively in some sub-pixels having the optical compensation layer.

[0188] The following will describe Test Example 1Ex1, which describes an organic stack in which an optical compensation layer is disposed between the anode and the cathode, and Test Example 2Ex1, which describes an organic stack in which an optical compensation layer is disposed between the reflective electrode and the anode (e.g., Figure 9 The driving voltage-current density characteristics and driving voltage-current characteristics of the light-emitting device of Test Example 2Ex2 (same as the red sub-pixel RS) are compared.

[0189] Figure 12 The diagram shows cross-sectional views of the light-emitting devices based on Test Example 1 and Test Example 2. Figure 13 The graphs show the driving voltage-current density characteristics and driving voltage-current characteristics of the light-emitting devices according to Test Example 1 and Test Example 2.

[0190] Figure 12 The various layer structures in the light-emitting devices according to Test Example 1Ex1 and Test Example 2Ex2 are shown. Each layer structure includes an anode, a cathode, and an organic stack disposed between the anode and the cathode.

[0191] In the light-emitting devices according to Test Example 1Ex1 and Test Example 2Ex2, two stacked bodies are provided, and the two stacked bodies are stacked with an n-type charge generation layer nCGL and a p-type charge generation layer pCGL inserted between them.

[0192] The light-emitting devices according to Test Example 1 and Test Example 2 commonly include, in the first stack S1, a hole injection layer HIL, a first hole transport layer HTL1, a first light-emitting layer EML1, a first hole blocking layer HBL1, and a first electron transport layer ETL1, which are sequentially stacked on the anode. Furthermore, the light-emitting device according to Test Example 1 includes, in the second stack S2, a second hole transport layer HTL2, an optical compensation layer R'HTL, a second light-emitting layer EML2, a second hole blocking layer HBL2, and a second electron transport layer ETL2, which are sequentially stacked.

[0193] In the light-emitting device according to Test Example 2, since the optical compensation layer R'HTL is located below the anode, the second stack body S2 according to Test Example 2 does not include the optical compensation layer R'HTL, compared to the second stack body S2 according to Test Example 1 which includes the optical compensation layer R'HTL.

[0194] Reference Figure 13 As a result of checking the current density of the light-emitting device according to Test Example 1Ex1 and Test Example 2Ex2 by the first curve 811 and the second curve 812 while changing the driving voltage from AV to 2.2AV, it can be confirmed that the current density of the light-emitting device according to Test Example 2Ex2 starts to increase from a driving voltage of about 1.3AV.

[0195] Furthermore, it can be confirmed that when the driving voltage is higher than or equal to 1.5A, the current value of the light-emitting device according to Test Example 2Ex2, shown in the fourth curve 822, increases compared to the current value of the light-emitting device according to Test Example 1Ex1 shown in the third curve 821. For example, to obtain a driving current of 1.0E-03A, the light-emitting device according to Test Example 2Ex2 requires a driving voltage of 1.9A, while the light-emitting device according to Test Example 1Ex1 requires a driving voltage of 2.2A. That is, to obtain the same driving current of 1.0E-03A, the light-emitting device according to Test Example 2Ex2 requires 86% of the driving voltage, i.e., 1.9A / 2.2A, compared to the light-emitting device according to Test Example 1Ex1, thus achieving a 14% reduction in driving voltage. Furthermore, it can be confirmed that the reduction in driving voltage further increases with increasing current value. Here, AV is the initial voltage required to turn on the light-emitting device and can vary from 2V to 5V.

[0196] Thus, the light-emitting display device according to the present invention includes an optical compensation layer located between the reflective electrode and the anode, rather than between the anode and the cathode, thereby reducing the thickness of the organic stack that leads to an increase in driving voltage. Furthermore, the optical compensation layer is located between the reflective electrode and the anode, and is thus provided during the thin-film transistor array formation process rather than during the deposition process for forming the organic stack. This eliminates the need for a fine metal mask and a chamber for forming the optical compensation layer, thereby increasing process yield.

[0197] Furthermore, the optical compensation layer located between the reflective electrode and the anode is formed of a transparent inorganic insulating film, which reduces the use of organic materials required for the organic stack and significantly reduces the driving voltage due to the reduced thickness of the organic stack in the light-emitting device.

[0198] Furthermore, an auxiliary optical compensation layer is formed in the organic stack along with the process for forming the light-emitting layer. The auxiliary optical compensation layer is configured to adjust the subtle differences between individual sub-pixels required by each device, thus enabling fine adjustment in each sub-pixel without adding a separate mask.

[0199] Furthermore, in a structure having multiple organic stacks, an auxiliary optical compensation layer is disposed in each of the stacks or in at least some of the stacks adjacent to the light-emitting layer, and the auxiliary optical compensation layer has a thickness less than or equal to 0.22 times the thickness of the optical compensation layer, thereby maintaining the driving voltage reduction effect without significantly increasing the thickness of the organic stacks, and being able to compensate for differences in device structure.

[0200] For this purpose, a light-emitting display device according to one embodiment of the present invention may include: a substrate including a first sub-pixel and a second sub-pixel; a first reflective electrode and a second reflective electrode respectively at the first sub-pixel and the second sub-pixel; a first optical compensation layer on the first reflective electrode; a first anode in contact with the first optical compensation layer and a second anode in contact with the second reflective electrode; a first unit having at least one first stack, the first stack including a first common layer, a first light-emitting layer emitting light having a first wavelength, and a second common layer sequentially stacked on the first anode; a second unit having at least one second stack, the second stack including a first common layer, a second light-emitting layer emitting light having a second wavelength shorter than the first wavelength, and the second common layer sequentially stacked on the second anode; and a cathode on the first unit and the second unit.

[0201] The first optical compensation layer can be a transparent inorganic insulating film.

[0202] The light-emitting display device may further include a first auxiliary optical compensation layer between the first common layer and the first light-emitting layer.

[0203] The first auxiliary optical compensation layer may have the same width as the first light-emitting layer.

[0204] The thickness of the first auxiliary optical compensation layer may be less than or equal to 0.22 times the thickness of the first optical compensation layer.

[0205] By using a charge generation layer commonly disposed in the first sub-pixel and the second sub-pixel, a plurality of first stacked bodies in the first sub-pixel can be separated from each other and a plurality of second stacked bodies in the second sub-pixel can be separated from each other; and a first auxiliary optical compensation layer may be further disposed between the first common layer and the first light-emitting layer in at least one of the plurality of first stacked bodies.

[0206] The first anode and the first reflective electrode may extend from one side of the first optical compensation layer and thus be connected to each other.

[0207] The light-emitting display device may further include: a first thin-film transistor and a second thin-film transistor at the first sub-pixel and the second sub-pixel of the substrate, respectively; a protective film covering the first thin-film transistor and the second thin-film transistor; and a first contact hole and a second contact hole through the protective film to expose a portion of each of the first thin-film transistor and the second thin-film transistor, wherein the first reflective electrode and the second reflective electrode may be connected to the first thin-film transistor and the second thin-film transistor, respectively, through the first contact hole and the second contact hole.

[0208] The first contact hole may overlap with the connection area between the first anode and the first reflective electrode.

[0209] The first auxiliary optical compensation layer may include the same material as the matrix of the first light-emitting layer.

[0210] The substrate may further include a third sub-pixel, and the light-emitting display device may further include: a third reflective electrode at the third sub-pixel and a third anode disposed on the third reflective electrode; and at least one third stack, the third stack including a first common layer, a third light-emitting layer emitting light having a third wavelength between the first wavelength and the second wavelength, and a second common layer sequentially stacked on the three anodes, and the cathode may be disposed on the at least one third stack.

[0211] The light-emitting display device may further include a second optical compensation layer, which is located between the third reflective electrode and the third anode and has a thickness smaller than that of the first optical compensation layer.

[0212] The light-emitting display device may further include a second auxiliary optical compensation layer between the first common layer and the third light-emitting layer.

[0213] The thickness of the first light-emitting layer, the thickness of the third light-emitting layer, and the thickness of the second light-emitting layer can be decreased sequentially, and an electron blocking layer can be further provided between the first common layer and the second light-emitting layer.

[0214] A light-emitting display device according to another embodiment of the present invention may include: a substrate having a first sub-pixel, a second sub-pixel, and a third sub-pixel; a first reflective electrode, a second reflective electrode, and a third reflective electrode at the first sub-pixel, the second sub-pixel, and the third sub-pixel, respectively; a first optical compensation layer on the first reflective electrode and a second optical compensation layer on the third reflective electrode, the second optical compensation layer having a thickness smaller than that of the first optical compensation layer; a first anode in contact with the first optical compensation layer, a second anode in contact with the second reflective electrode, and a third anode in contact with the second optical compensation layer; a dam portion overlapping the edges of the first anode, the second anode, and the third anode and opening the first light-emitting portion, the second light-emitting portion, and the third light-emitting portion at the first sub-pixel, the second sub-pixel, and the third sub-pixel; a first common layer on the first light-emitting portion, the second light-emitting portion, the third light-emitting portion, and the dam portion; a first light-emitting layer, a second light-emitting layer, and a third light-emitting layer at the first light-emitting portion, the second light-emitting portion, and the third light-emitting portion, respectively; a second common layer on the first light-emitting portion, the second light-emitting portion, and the third light-emitting portion; and a cathode on the second common layer.

[0215] The first optical compensation layer and the second optical compensation layer can be transparent inorganic insulating films.

[0216] The light-emitting display device may further include a first auxiliary optical compensation layer between the first common layer and the first light-emitting layer.

[0217] The light-emitting display device may further include a second auxiliary optical compensation layer between the first common layer and the third light-emitting layer.

[0218] The first auxiliary optical compensation layer may have the same width as the first light-emitting layer, and the second auxiliary optical compensation layer may have the same width as the third light-emitting layer.

[0219] The thickness of the first auxiliary optical compensation layer may be less than or equal to 0.22 times the thickness of the first optical compensation layer, and the thickness of the second auxiliary optical compensation layer may be less than or equal to 0.22 times the thickness of the second optical compensation layer.

[0220] The light-emitting display device may further include, in the vertical structure of each of the first sub-pixel, the second sub-pixel, and the third sub-pixel: at least one first stacked light-emitting layer overlapping the first light-emitting layer in the first sub-pixel; at least one second stacked light-emitting layer overlapping the second light-emitting layer in the second sub-pixel; at least one third stacked light-emitting layer overlapping the third light-emitting layer in the third sub-pixel; a first stacked common layer located in the same layer between the at least one first stacked light-emitting layer, the at least one second stacked light-emitting layer, and the at least one third stacked light-emitting layer and the second common layer; and a second stacked common layer between the at least one first stacked light-emitting layer, the at least one second stacked light-emitting layer, and the at least one third stacked light-emitting layer and the cathode.

[0221] The first anode, the second anode, and the third anode may be transparent electrodes, and the cathode may be a semi-transmissive / semi-reflective electrode or a transmissive electrode.

[0222] The first reflective electrode, the second reflective electrode, and the third reflective electrode can be connected to the thin-film transistor on the substrate through the first transparent electrode layer, the second transparent electrode layer, and the third transparent electrode layer, respectively. The first transparent electrode layer, the second transparent electrode layer, and the third transparent electrode layer are respectively inserted between the first reflective electrode, the second reflective electrode, and the third reflective electrode and the thin-film transistor.

[0223] It is evident from the above description that the light-emitting display device according to the present invention has the following effects.

[0224] First, the optical compensation layer is located between the reflective electrode and the anode, rather than between the anode and the cathode, thereby reducing the thickness of the organic stack that leads to increased driving voltage. Furthermore, by placing the optical compensation layer between the reflective electrode and the anode, it is provided during the thin-film transistor array formation process rather than during the deposition process for forming the organic stack. This eliminates the need for a fine metal mask and a chamber for forming the optical compensation layer, thus increasing process yield.

[0225] Second, the optical compensation layer located between the reflective electrode and the anode is formed of a transparent inorganic insulating film, which reduces the amount of organic material required for the organic stack and significantly reduces the driving voltage due to the reduced thickness of the organic stack in the light-emitting device. Furthermore, the current can be increased under the same low driving voltage.

[0226] Third, an auxiliary optical compensation layer is formed in the organic stack along with the process for forming the light-emitting layer. The auxiliary optical compensation layer is configured to adjust the subtle differences between individual sub-pixels required by each device, thus enabling fine adjustment in each sub-pixel without adding a separate mask.

[0227] Fourth, in a structure having multiple organic stacks, an auxiliary optical compensation layer is disposed in each of the stacks or in at least some of the stacks adjacent to the light-emitting layer, and the auxiliary optical compensation layer has a thickness less than or equal to 0.22 times the thickness of the optical compensation layer, thereby maintaining the driving voltage reduction effect without significantly increasing the thickness of the organic stacks, and being able to compensate for differences in device structure.

[0228] It will be apparent to those skilled in the art that various modifications and variations can be made to this invention without departing from the spirit or scope thereof. Therefore, this invention is intended to cover any modifications and variations falling within the scope of the appended claims and their equivalents.

Claims

1. A light-emitting display device, comprising: A substrate including the first sub-pixel and the second sub-pixel; The first reflective electrode and the second reflective electrode are respectively located at the first sub-pixel and the second sub-pixel; A first optical compensation layer on the first reflective electrode; A first anode in contact with the first optical compensation layer and a second anode in contact with the upper surface of the second reflective electrode; A first unit having at least one first stack body, the first stack body comprising a first common layer, a first light-emitting layer emitting light having a first wavelength, and a second common layer sequentially stacked on the first anode; A second unit having at least one second stack body, the second stack body comprising a first common layer sequentially stacked on a second anode, a second light-emitting layer emitting light having a second wavelength shorter than the first wavelength, and the second common layer; as well as The cathodes on the first unit and the second unit, Wherein the first sub-pixel is a red sub-pixel and the second sub-pixel is a blue sub-pixel, and No optical compensation layer is provided in the second sub-pixel.

2. The light-emitting display device according to claim 1, wherein the first optical compensation layer is a transparent inorganic insulating film.

3. The light-emitting display device according to claim 1, further comprising a first auxiliary optical compensation layer between the first common layer and the first light-emitting layer.

4. The light-emitting display device according to claim 3, wherein the first auxiliary optical compensation layer has the same width as the first light-emitting layer.

5. The light-emitting display device according to claim 3, wherein the thickness of the first auxiliary optical compensation layer is less than or equal to 0.22 times the thickness of the first optical compensation layer.

6. The light-emitting display device according to claim 1, wherein: By means of at least one charge generation layer commonly disposed in the first sub-pixel and the second sub-pixel, a plurality of first stacked bodies in the first sub-pixel are separated from each other and a plurality of second stacked bodies in the second sub-pixel are separated from each other; and A first auxiliary optical compensation layer is further disposed between the first common layer and the first light-emitting layer in at least one of the plurality of first stacks.

7. The light-emitting display device according to claim 6, wherein the first auxiliary optical compensation layer comprises the same material as the matrix of the first light-emitting layer.

8. The light-emitting display device according to claim 1, wherein the first anode and the first reflective electrode extend from one side of the first optical compensation layer and are connected to each other.

9. The light-emitting display device according to claim 8, further comprising: A first thin-film transistor and a second thin-film transistor at the first sub-pixel and the second sub-pixel of the substrate, respectively; A protective film covering the first thin-film transistor and the second thin-film transistor; and The first contact hole and the second contact hole are exposed through the protective film to expose a portion of each of the first thin-film transistor and the second thin-film transistor. The first reflective electrode and the second reflective electrode are respectively connected to each of the first thin-film transistor and the second thin-film transistor through the first contact hole and the second contact hole.

10. The light-emitting display device according to claim 9, wherein the first contact hole overlaps with the connection area between the first anode and the first reflective electrode.

11. The light-emitting display device according to claim 1, wherein the substrate further comprises a third sub-pixel. The light-emitting display device further includes: A third reflective electrode at the third sub-pixel and a third anode disposed on the third reflective electrode; and At least one third stack comprising a first common layer sequentially stacked on the third anode, a third light-emitting layer emitting light having a third wavelength between the first wavelength and the second wavelength, and the second common layer. The cathode is disposed on the at least one third stack.

12. The light-emitting display device according to claim 11, further comprising a second optical compensation layer, the second optical compensation layer being between the third reflective electrode and the third anode and having a thickness smaller than that of the first optical compensation layer.

13. The light-emitting display device according to claim 11, further comprising a second auxiliary optical compensation layer between the first common layer and the third light-emitting layer.

14. The light-emitting display device according to claim 11, wherein: The thicknesses of the first light-emitting layer, the third light-emitting layer, and the second light-emitting layer decrease sequentially; and An electron blocking layer is further disposed between the first common layer and the second light-emitting layer.

15. A light-emitting display device, comprising: A substrate having a first sub-pixel, a second sub-pixel, and a third sub-pixel; A first reflective electrode, a second reflective electrode, and a third reflective electrode are respectively located at the first sub-pixel, the second sub-pixel, and the third sub-pixel; A first optical compensation layer on the first reflective electrode and a second optical compensation layer on the third reflective electrode, wherein the second optical compensation layer has a thickness smaller than that of the first optical compensation layer; A first anode in contact with the first optical compensation layer, a second anode in contact with the upper surface of the second reflective electrode, and a third anode in contact with the second optical compensation layer; A dam portion, which overlaps with the edges of the first anode, the second anode, and the third anode and opens the first light-emitting portion, the second light-emitting portion, and the third light-emitting portion in the first sub-pixel, the second sub-pixel, and the third sub-pixel; A first common layer on the first light-emitting part, the second light-emitting part, the third light-emitting part, and the embankment; A first light-emitting layer, a second light-emitting layer, and a third light-emitting layer are respectively located at the first light-emitting part, the second light-emitting part, and the third light-emitting part; A second common layer on the first light-emitting part, the second light-emitting part, and the third light-emitting part; as well as The cathode on the second common layer, The first sub-pixel is a red sub-pixel, the second sub-pixel is a blue sub-pixel, and the third sub-pixel is a green sub-pixel.

16. The light-emitting display device according to claim 15, wherein the first optical compensation layer and the second optical compensation layer are transparent inorganic insulating films.

17. The light-emitting display device according to claim 15, further comprising at least one of a first auxiliary optical compensation layer between the first common layer and the first light-emitting layer and a second auxiliary optical compensation layer between the first common layer and the third light-emitting layer.

18. The light-emitting display device according to claim 17, wherein: The first auxiliary optical compensation layer has the same width as the first light-emitting layer; and The second auxiliary optical compensation layer has the same width as the third light-emitting layer.

19. The light-emitting display device according to claim 15, wherein: The first anode, the second anode, and the third anode are transparent electrodes; and The cathode is a semi-transmissive / semi-reflective electrode or a transmissive electrode.

20. The light-emitting display device according to claim 15, wherein the first reflective electrode, the second reflective electrode and the third reflective electrode are respectively connected to a thin-film transistor on the substrate through a first transparent electrode layer, a second transparent electrode layer and a third transparent electrode layer, and the first transparent electrode layer, the second transparent electrode layer and the third transparent electrode layer are respectively inserted between the first reflective electrode, the second reflective electrode and the third reflective electrode and the thin-film transistor.

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