Organic light emitting display device

Abstract

An organic light emitting display device is provided. The organic light-emitting display device comprises a substrate, wherein a red sub-pixel, a blue sub-pixel, a first green sub-pixel and a second green sub-pixel are arranged on the substrate; an anode; a first hole transport layer; a first red organic light-emitting layer, a first blue organic light-emitting layer, a first green organic light-emitting layer, and a second green organic light-emitting layer; a charge generation layer; an electron transport layer; and a cathode, in which the second green sub-pixel includes an additional auxiliary hole transport layer compared to the first green sub-pixel, such that the second green sub-pixel has a greater light emission characteristic than the first green sub-pixel.

Description

[0001] CROSS-REFERENCE TO RELATED APPLICATIONS

[0002] This application claims the benefit of Korean Patent Application No. 10-2024-0029835 filed on February 29, 2024, in the Korean Intellectual Property Office, the disclosure of which is incorporated herein by reference. Technical Field

[0003] The present disclosure relates to an organic light emitting display device, and particularly, to an organic light emitting display device that ensures improved light emitting efficiency of a green sub-pixel. Background Art

[0004] Unlike liquid crystal display devices, organic light-emitting display devices do not require a separate light source and can be manufactured as lightweight and thin devices. In addition, organic light-emitting display devices ensure excellent color realization, response speed, viewing angle, contrast ratio (CR), and consume less power due to low voltage driving, and have been studied as next-generation display devices.

[0005] An organic light-emitting display device, which is a self-luminous display device, is a display device using an organic light-emitting diode, which emits light when excitons coupled by injected electrons and injected holes therein fall from an excited state to a ground state by injecting electrons and holes from a cathode for injecting electrons and an anode for injecting holes, respectively.

[0006] Organic light-emitting display devices are classified into top-emission and bottom-emission methods, depending on the direction in which light generated by the organic light-emitting layer is emitted. In the case of a top-emission organic light-emitting display device, light emitted from the organic light-emitting layer is emitted upward through a cathode. Furthermore, a top-emission organic light-emitting display device can ensure a larger aperture ratio than a bottom-emission organic light-emitting display device, whose aperture ratio is affected by the thin-film transistors disposed below the organic light-emitting layer. Therefore, in recent years, research on top-emission organic light-emitting display devices has been actively conducted. Summary of the Invention

[0007] One object of the present disclosure is to provide an organic light-emitting display device having a first green sub-pixel and a second green sub-pixel, wherein the first green sub-pixel and the second green sub-pixel have different light-emitting characteristics, so that the generation of afterimages and the degradation of brightness caused by viewing angle changes can be improved when driven at low grayscale.

[0008] Another object of the present disclosure is to provide an organic light emitting display device including a green sub-pixel, which ensures excellent light emitting efficiency and brightness characteristics and reduces driving voltage.

[0009] Yet another object of the present disclosure is to provide an organic light emitting display device capable of simultaneously driving green sub-pixels having different light emitting characteristics without requiring additional manufacturing processes and additional driving methods.

[0010] The objects of the present disclosure are not limited to the above objects, and other objects not mentioned above can be clearly understood by those skilled in the art from the following description.

[0011] An organic light-emitting display device according to one embodiment includes: a substrate on which a red sub-pixel, a blue sub-pixel, a first green sub-pixel, and a second green sub-pixel are arranged; an anode, which is respectively arranged at each of the red sub-pixel, the blue sub-pixel, the first green sub-pixel, and the second green sub-pixel; a first hole transport layer arranged on the anode; a first auxiliary hole transport layer arranged on the first hole transport layer at the blue sub-pixel and the second green sub-pixel; a first red organic light-emitting layer, a first blue organic light-emitting layer, a first green organic light-emitting layer, and a second green organic light-emitting layer, which are respectively arranged at the red sub-pixel, the blue sub-pixel, the first green sub-pixel, and the second green sub-pixel; and a first auxiliary hole transport layer arranged on the red organic light-emitting layer, the blue organic light-emitting layer, the first green organic light-emitting layer, and the second green organic light-emitting layer. a charge generating layer on the red organic light-emitting layer and the second green organic light-emitting layer; a second auxiliary hole transport layer arranged on the charge generating layer; a second red organic light-emitting layer, a second blue organic light-emitting layer, a third green organic light-emitting layer and a fourth green organic light-emitting layer arranged on the second auxiliary hole transport layer at each of the red sub-pixel, the blue sub-pixel, the first green sub-pixel and the second green sub-pixel; an electron transport layer arranged on the second red organic light-emitting layer, the second blue organic light-emitting layer, the third green organic light-emitting layer and the fourth green organic light-emitting layer; and a cathode arranged on the electron transport layer, wherein the second auxiliary hole transport layer includes a second green auxiliary hole transport layer and a second blue auxiliary hole transport layer arranged at the second green sub-pixel.

[0012] Additional details of exemplary embodiments are included in the detailed description and accompanying drawings.

[0013] In an organic light emitting display device according to one embodiment, the overall height of the light emitting diode and the optical distance of the organic light emitting layer may be changed, thereby providing two green sub-pixels having different optical characteristics.

[0014] In an organic light-emitting display device of one embodiment, an auxiliary hole transport layer or an electron blocking layer of a blue sub-pixel may be additionally provided at a green sub-pixel, thereby providing an organic light-emitting display device including a second green sub-pixel, which ensures excellent luminous efficiency and brightness and reduces driving voltage.

[0015] In the organic light emitting display device of one embodiment, at the time of low grayscale driving, problems such as unintended emission of light or afterimages may be solved, and light emitting characteristics of a green sub-pixel may be improved.

[0016] In the organic light emitting display device of one embodiment, luminance degradation depending on a viewing angle of a green sub-pixel may be improved.

[0017] The effects according to the present disclosure are not limited to the contents of the above examples, and more various effects are included in this specification. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] The above and other aspects, features and other advantages of the present disclosure will be more clearly understood from the following detailed description taken in conjunction with the accompanying drawings, in which:

[0019] Figure 1 is a schematic plan view of an organic light emitting display device according to an embodiment;

[0020] Figure 2 yes Figure 1 An enlarged plan view of area A;

[0021] Figure 3 is a schematic cross-sectional view of an organic light-emitting display device according to an embodiment;

[0022] Figure 4 is a graph showing current density characteristics of driving voltage of a green sub-pixel according to Comparative Example 1 and Example 1; and

[0023] Figure 5 This is a graph showing the luminous efficiency characteristics depending on the thickness of the auxiliary hole transport layer of the green sub-pixel in Comparative Example 2 and Example 1. DETAILED DESCRIPTION

[0024] The advantages and features of the present disclosure and methods for achieving the advantages and features will become clear by referring to the exemplary embodiments described in detail below in conjunction with the accompanying drawings. However, the present disclosure is not limited to the exemplary embodiments disclosed herein, but will be implemented in various forms. The exemplary embodiments are provided only by way of example so that those skilled in the art can fully understand the disclosure and scope of the present disclosure.

[0025] The shapes, sizes, ratios, angles, quantities, etc. used to describe the exemplary embodiments of the present disclosure shown in the accompanying drawings are merely examples, and the present disclosure is not limited thereto. Throughout the specification, similar reference numerals generally represent similar elements. In addition, in the following description of the present disclosure, detailed descriptions of known related arts may be omitted to avoid unnecessarily obscuring the subject matter of the present disclosure. Terms such as "including," "having," and "consisting of" used herein are generally intended to allow the addition of other components unless the term is used together with the term "only." Unless otherwise expressly stated, any reference to the singular may include the plural.

[0026] Components are interpreted as including ordinary margins of error even if not expressly stated.

[0027] When terms such as “on,” “above,” “below,” and “beside” are used to describe a positional relationship between two components, one or more components may be located between the two components unless the terms are used with the terms “immediately” or “directly.”

[0028] When an element or layer is referred to as being “on” another element or layer, the other layer or element can be directly on or positioned between the other element.

[0029] Although the terms "first," "second," and the like are used to describe various components, these components are not limited by these terms. These terms are only used to distinguish one component from other components. Therefore, in the technical concept of the present disclosure, the first component mentioned below may be the second component.

[0030] Like reference numerals generally refer to like elements throughout the specification.

[0031] The size and thickness of each component shown in the drawings are shown for convenience of description, and the present disclosure is not limited to the size and thickness of the components shown.

[0032] The features of the various embodiments of the present disclosure may be partially or completely bonded or combined with each other and may be interlocked and operated in various technical ways, and the embodiments may be performed independently or in association with each other.

[0033] Hereinafter, a display device according to an exemplary embodiment of the present disclosure will be described in detail with reference to the accompanying drawings.

[0034] Figure 1-Figure 3 is a diagram illustrating an organic light emitting display device according to one embodiment. Figure 1 is a schematic plan view of an organic light emitting display device according to an embodiment. Figure 2 yes Figure 1 An enlarged plan view of area A. Figure 3 is a schematic cross-sectional view of an organic light-emitting display device according to an embodiment.

[0035] The organic light emitting display device 100 according to one embodiment includes an image processor 11 , a timing controller 12 , a data driver 13 , a scan driver 14 , and a display panel 15 .

[0036] The image processor 11 outputs a data enable signal DE and a data signal DATA provided from the outside. In addition to the data enable signal DE, the image processor 11 may also output one or more of a vertical synchronization signal, a horizontal synchronization signal, and a clock signal. The image processor 11 is formed as an integrated circuit (IC) on a system circuit board.

[0037] The timing controller 12 is supplied with a data signal DATA and a data enable signal DE or drive signals including a vertical synchronization signal, a horizontal synchronization signal, and a clock signal, etc., from the image processor 11. The timing controller 12 outputs a gate timing control signal GDC for controlling the operation timing of the scan driver 14 and a data timing control signal DDC for controlling the operation timing of the data driver 13 based on the drive signals. The timing controller 12 is formed in an IC on a control circuit board.

[0038] The data driver 13 samples and latches the data signal DATA supplied from the timing controller 12 in response to the data timing control signal DDC supplied from the timing controller 12, and converts the sampled and latched data signal DATA into a gamma reference voltage and outputs it. The data driver 13 supplies the data signal DATA converted through the data lines DL1-DLn to the sub-pixels SP included in the display panel 15. The data driver 13 may be formed as an integrated circuit (IC).

[0039] The scan driver 14 continuously generates scan signals in response to the gate timing control signal GDC provided from the timing controller 12. The scan driver 14 provides the scan signals generated by the scan lines GL1-GLm to the sub-pixels SP. The scan driver 14 may be formed in an IC on a gate circuit board or may be formed on the display panel 15 based on a gate in panel (GIP) method.

[0040] The display panel 15 displays an image in response to the data signal DATA and the gate signals supplied from the data driver 13 and the scan driver 14. The display panel 15 includes a plurality of sub-pixels SP that display an image.

[0041] Reference Figure 1, an organic light-emitting display device 100 of one embodiment includes a display area DA and a non-display area NDA. The display area DA is an area where a plurality of sub-pixels SP are provided and which substantially displays an image. In the display area DA, a plurality of sub-pixels SP may be provided, which include an emission area for displaying an image and a driving circuit for driving the sub-pixels SP. The sub-pixel SP, which is an element for displaying one color, includes an emission area that emits light and a non-emission area that does not emit light, but in the present disclosure, the emission area that emits light is defined only as a sub-pixel. The plurality of sub-pixels SP are arranged in a matrix form. The non-display area NDA surrounds the display area DA. In the non-display area NDA, which is an area where no image is substantially displayed, various wirings, driver ICs, printed circuit boards, etc. for driving the pixels and driving circuits provided in the display area DA are provided. For example, in the non-display area NDA, various ICs such as a gate driver IC and a data driver IC, VSS wiring, etc. may be provided.

[0042] Multiple sub-pixels SP are arranged in a matrix. Multiple sub-pixels SP can constitute a pixel unit. For example, referring to Figure 2 , a pixel unit may include a first sub-pixel, a second sub-pixel, a third sub-pixel, and a fourth sub-pixel. The first sub-pixel, the second sub-pixel, the third sub-pixel, and the fourth sub-pixel may display different colors respectively, or if necessary, some sub-pixels may display the same color. In an organic light-emitting display device 100 of one embodiment, the first sub-pixel is a red sub-pixel SPR, the second sub-pixel is a first green sub-pixel SPG1, the third sub-pixel is a blue sub-pixel SPB, and the fourth sub-pixel is a second green sub-pixel SPG2. Figure 2 , the area indicated by shading is the emission area of ​​each sub-pixel, and the remaining area not indicated by shading is the non-emission area.

[0043] At this time, the red, blue, first, and second green sub-pixels (SPR, SPB, SPG1, and SPG2) can be arranged in a pentile structure. When the red, blue, first, and second green sub-pixels (SPR, SPB, SPG1, and SPG2) are arranged in a pentile structure, the number of red and blue sub-pixels (SPR and SPB) in the display area DA can be smaller than when the red, blue, first, and second green sub-pixels (SPR, SPB, SPG1, and SPG2) are arranged in a stripe structure. When the number of sub-pixels (SP) is reduced, the aperture ratio can be improved while maintaining the same level of perceived resolution compared to a stripe structure. Furthermore, the reduction in the number of sub-pixels (SP) can simplify the manufacturing process of the organic light-emitting display panel and improve power consumption. In the pentile structure, the surface area of ​​the first and second green sub-pixels (SPG1 and SP2) can be smaller than that of the red and blue sub-pixels (SPG and SPB), taking into account brightness and color temperature. For example, the red sub-pixels SPR and the blue sub-pixels SPB may be alternately arranged in a first direction (X-axis direction), and the first green sub-pixels SPG1 and the second green sub-pixels SPG2 may be spaced apart from the red sub-pixels SPR and the blue sub-pixels SPB in a second direction (Y-axis direction) and alternately arranged along the first direction (X-axis direction), but are not limited thereto.

[0044] exist Figure 2 In FIG, the red sub-pixel, the blue sub-pixel, the first green sub-pixel and the second green sub-pixel SPR, SPB, SPG1 and SPG2 are formed into, for example but not limited to, a pentile structure. If necessary, the color and arrangement of the sub-pixels may be changed. In addition, in Figure 2 In the embodiment, each of the red sub-pixel, the blue sub-pixel, the first green sub-pixel, and the second green sub-pixel SPR, SPB, SPG1, and SPG2 may be shaped, for example, as an octagon, but is not limited thereto and may have various shapes. For example, each sub-pixel may be shaped as a polygon other than a circle, an ellipse, or an octagon.

[0045] like Figure 3 As shown, each of the red sub-pixel, the blue sub-pixel, the first green sub-pixel and the second green sub-pixel SPR, SPB, SPG1, SPG2 includes a substrate 110, an organic light-emitting diode 130 that emits light, a thin film transistor 120 for transmitting a driving voltage to the organic light-emitting diode 130, and a capping layer 140 for protecting the organic light-emitting diode 130 or enhancing light output efficiency.

[0046] The substrate 110 supports and protects the various components of the organic light-emitting display device 100. The substrate 110 can be made of an insulating material, for example, a flexible material such as glass or polyimide. If the organic light-emitting display device 100 is a flexible organic light-emitting display device 100, the organic light-emitting display device 100 can be made of a flexible material such as plastic. Furthermore, if the flexible organic light-emitting diode 130 is applied to a lighting device or a display device for a vehicle, the lighting device or the display device for a vehicle can be freely designed in various ways according to the structure and exterior shape of the vehicle.

[0047] In addition, the organic light-emitting display device 100 of one embodiment can be applied to TVs, mobile devices, tablet PCs, monitors, laptop computers, display devices (including display devices for vehicles, etc.), etc. Alternatively, the organic light-emitting display device 100 of one embodiment can also be applied to wearable display devices, foldable display devices, rollable display devices, etc.

[0048] The thin film transistor 120 is provided on the substrate 110. For example, each of the red sub-pixel, the blue sub-pixel, the first green sub-pixel, and the second green sub-pixel SPR, SPB, SPG1, and SPG2 may include a driving thin film transistor connected to the anode 131 of the organic light emitting diode 130, a switching thin film transistor for driving the organic light emitting diode 130, a capacitor, and the like.

[0049] A planarization layer is provided on the thin film transistor 120. The planarization layer, which is a layer for planarizing the upper portion of the substrate 110, may be formed of an organic insulating material to cover a step on the upper portion of the substrate 110. The planarization layer includes a contact hole for electrically connecting the anode 131 of each of the red sub-pixel, the blue sub-pixel, the first green sub-pixel, and the second green sub-pixel SPR, SPB, SPG1, and SPG2 to the thin film transistor 120.

[0050] On the planarization layer, an organic light emitting diode 130 is provided in response to each of the red sub-pixel, the blue sub-pixel, the first green sub-pixel, and the second green sub-pixel SPR, SPB, SPG1, and SPG2. Figure 3As shown, one pixel of an organic light-emitting display device 100 according to one embodiment includes a red sub-pixel, a blue sub-pixel, a first green sub-pixel, and a second green sub-pixel SPR, SPB, SPG1, and SPG2. The red sub-pixel SPR includes a red organic light-emitting diode, the blue sub-pixel SPB includes a blue organic light-emitting diode, the first green sub-pixel SPG1 includes a first green organic light-emitting diode, and the second green sub-pixel SPG2 includes a second green organic light-emitting diode. The red, blue, first green, and second green organic light-emitting diodes 130 are disposed on a planarization layer and each include an anode 131, an intermediate layer IL, and a cathode 135.

[0051] For each sub-pixel SPR, SPB, SPG1, and SPG2, an anode 131 is provided on the planarization layer. The anode 131 is an electrode configured to provide holes to the organic light-emitting layer in the intermediate layer IL. The anode 131 can be made of a transparent conductive transparent material with a high work function. Here, the transparent conductive material can include indium tin oxide (ITO), indium zinc oxide (IZO), and indium tin zinc oxide (ITZO). The anode 131 is electrically connected to the thin film transistor 120 through a contact hole formed in the planarization layer.

[0052] The cathode 135 is provided on the anode 131. The cathode 135, which is an electrode for providing electrons, may be made of a metal material having a relatively low work function, such as silver (Ag), titanium (Ti), aluminum (Al), molybdenum (Mo), an alloy of silver (Ag) and magnesium (Mg) (Ag:Mg), or an alloy of magnesium (Mg) and lithium fluoride (Mg:LiF). The cathode 135 may be composed of at least two or more layers. In addition, in the case where the cathode 135 is made of an alloy of silver (Ag) and magnesium (Mg) (Ag:Mg), the content of silver (Ag) may be greater than the content of magnesium (Mg) to reduce the resistance of the cathode 135. Figure 3 , for each sub-pixel SPR, SPB, SPG1, SPG2, the cathode 135 set in each sub-pixel SPR, SPB, SPG1, SPG2 is separated, but the cathode 135 set in each sub-pixel SPR, SPB, SPG1, SPG2 can be connected to each other and formed together.

[0053] The intermediate layer IL is provided between the anode 131 and the cathode 135. The intermediate layer IL is a layer including a plurality of emission portions 132, 134 and made of an organic material. Figure 3In one embodiment, an organic light-emitting display device 100 has a stacked structure, in which multiple light-emitting portions 132 and 134 are stacked in one sub-pixel. Specifically, each sub-pixel SPR, SPB, SPG1, and SPG2 can have a dual-stacked structure, including a first emission portion 132 including a first organic light-emitting layer and a second emission portion 134 including a second organic light-emitting layer.

[0054] The intermediate layer IL constituting the red, blue, first green, and second green organic light emitting diodes 130 includes a first emission portion 132 , a charge generation layer 133 , and a second emission portion 134 , respectively.

[0055] The first emission portion 132 is disposed on the anode 131. The first emission portion 132 may include a hole injection layer HIL, a first hole transport layer HTL1, a first organic light emitting layer EML1, and a first electron transport layer ETL1.

[0056] The hole injection layer (HIL) smoothly injects holes from the anode 131 into the organic light-emitting layer. The hole injection layer (HIL) can be formed collectively at the red, blue, first, and second green subpixels SPR, SPB, SPG1, and SPG2. The HIL can be selected from, but not limited to, arylamine-based NATA, 2T-NATA, and NPNPB, and p-doped systems such as F4-TCNQ and PPDN. Depending on the structure or characteristics of the light-emitting diode, the HIL can be omitted.

[0057] The first hole transport layer HTL1 smoothly injects holes from the anode 131 into the first organic light emitting layer EML1. The first hole transport layer HTL1 may be generally formed at the red, blue, first, and second green sub-pixels SPR, SPB, SPG1, and SPG2. The first hole transport layer HTL1 may be made of any one or more selected from the group consisting of TPD (N,N'-bis-(3-methylphenyl)-N,N'-bis-(phenyl)-benzidine), PPD, TTBND, FFD, p-dmDPS, TAPC based on aromatic amines, TCTA, PTDATA, TDAPB, TDBA, 4-a, TCTA based on star-shaped aromatic amines, spiro-TPD, spiro-MTTB, spiro-2 (which is a spiro and ladder-type material), NPD (N,N-dinaphthyl-N,N'-diphenylbenzidine), s-TAD and MTDATA (4,4',4"-tris(N-3-methylphenyl-N-phenyl-amino)-triphenylamine), but is not limited thereto. The first hole transport layer HTL1 may be formed by applying two or more layers or two or more materials.

[0058] On the first hole transport layer HTL1, the first auxiliary hole transport layer B'HTL1 is formed only at the blue subpixel SPB and the second green subpixel SPG2 among the red, blue, first, and second green subpixels SPR, SPB, SPG1, and SPG2. As an optical auxiliary layer, the first auxiliary hole transport layer B'HTL1 regulates the distance between the anode 131 and the cathode 135, i.e., the optical path of the first organic light-emitting layer EML1. Therefore, when light emitted from the first organic light-emitting layer EML1 causes interference between the anode 131 and the cathode 135, luminous efficiency can be improved due to the microcavity effect. Furthermore, the first auxiliary hole transport layer B'HTL1 can block electrons in the first organic light-emitting layer EML1 from moving to the first hole transport layer HTL1.

[0059] In the case of the first auxiliary hole transport layer B'HTL1, the highest occupied molecular orbital (HOMO) energy level may be -5.4 to -5.3. In addition, in the case of the first auxiliary hole transport layer B'HTL1, the hole mobility may be 5×10 -8 to 5×10 -7 When the HOMO energy level and hole mobility of the first auxiliary hole transport layer B'HTL1 meet the above ranges, the first auxiliary hole transport layer B'HTL1 can be provided together with the second green auxiliary hole transport layer G'HTL2 to improve the luminous efficiency and life of the light emitting diode.

[0060] The first auxiliary hole transport layer B'HTL1 may include spyrofluorene. In this case, the first auxiliary hole transport layer B'HTL1 may include a deuterium-substituted compound. For example, the first auxiliary hole transport layer B'HTL1 may include a compound represented by the following Chemical Formula 1.

[0061] [Chemical Formula 1]

[0062]

[0063] In this context, L1 is a single bond or is selected from phenyl and naphthyl. R1 or R8 is substituted with deuterium. R9 and R 10 Selected from phenyl, biphenyl, heteroaryl, carbazolyl, dibenzofuranyl and dibenzothienyl substituted by deuterium.

[0064] The first auxiliary hole transport layer B'HTL1 blocks charge from moving to the first hole transport layer HTL1 and transfers holes from the anode 131 to the first blue organic light-emitting layer B_EML1 and the second green organic light-emitting layer G_EML1-2. Due to the stability of deuterium in the material comprising the first auxiliary hole transport layer B'HTL1, charges accumulated at the interface between the first auxiliary hole transport layer B'HTL1, the first blue organic light-emitting layer B_EML1, and the second green organic light-emitting layer G_EML1-2 can rebound and move back to the first blue organic light-emitting layer B_EML1 and the second green organic light-emitting layer G_EML1-2. Therefore, a reduction in diode lifetime due to accumulated charge can be prevented, and diode efficiency can be improved.

[0065] For each of the red, blue, first, and second green subpixels SPR, SPB, SPG1, and SPG2, a first organic light-emitting layer (EML1) is formed on the first hole transport layer (HTL1) and the first auxiliary hole transport layer (B'HTL1). Specifically, a first red organic light-emitting layer (R_EML1) is formed at the red subpixel (SPR), a first blue organic light-emitting layer (B_EML1) is formed at the blue subpixel (SPB), a first green organic light-emitting layer (G_EML1-1) is formed at the first green subpixel (SPG1), and a second green organic light-emitting layer (G_EML1-2) is formed at the second green subpixel (SPG2). Each first organic light-emitting layer (EML1) may have a different thickness. Materials known in the art to which the present disclosure pertains may be used as the material for the first organic light-emitting layer (EML1). For example, a material having good fluorescence quantum efficiency or good phosphorescence quantum efficiency may be used as the material for the first organic light-emitting layer (EML1).

[0066] Specifically, the first organic light-emitting layer EML1 may include a phosphorescent dopant material, a hole host material having hole transport capability, and an electron host material having electron transport capability. Typically, hole host materials having hole transport capability include carbazolyl hosts, triazine hosts, and other hosts. For example, hole host materials include α-NPD and TPD as arylamine-based hosts, TDAPB and TCTA as star-shaped aromatic amine hosts, and spiro-TAD and OTP-1 as spiro and ladder-shaped hosts.

[0067] In addition, the electron host material having electron transport capability includes a carbazole-based host, a triazine-based host, and other hosts. For example, the electron host material includes an organic metal compound, a sulfone derivative, an oxazole derivative, a triazole derivative, a bipyridine-containing silole derivative, a phenylbenzimidazole-containing compound, and a pyrene derivative. In addition, the electron mobility of the electron host material having electron transport capability can be 10 -3 to 10 -6 cm 2 / Vs value.

[0068] Specifically, the first red organic light-emitting layer R_EML1 may include a host material containing carbazole biphenyl (CBP) or mCP (1,3-bis(carbazole-9-yl)) as a specific example of a material for the first organic light-emitting layer EML1, and is made of a phosphorescent material containing a dopant containing one or more selected from the group consisting of PIQIr(acac) (bis(1-phenylisoquinoline) iridium acetylacetonate), PQIr(acac) (bis(1-phenylquinoline) iridium acetylacetonate), BtP2Ir(acac), PQIr (tris(1-phenylquinoline)iridium) and PtOEP (octaethylporphyrin platinum), and conversely, is made of PBD:Eu(DBM)3(Phen) or pyrene, but is not limited thereto.

[0069] The first blue organic light-emitting layer B_EML1 may include a host material comprising CBP or mCP and made of a phosphorescent material comprising a dopant material comprising (4,6-F2ppy)2Irpic, (F2ppy)2Ir(tmd) and Ir(dfppz)3, and conversely, the first blue organic light-emitting layer B_EML1 is made of a fluorescent material comprising any one selected from spiro-DPVBi, spiro-6P, distilled benzene (DSB), distyrylarylene (DSA), a PFO-based polymer and a PPV-based polymer, but is not limited thereto.

[0070] The first green organic light-emitting layer G_EML1-1 and the second green organic light-emitting layer G_EML1-2 may include a host material including CBP or mCP, a phosphorescent material including a dopant material including Ir(ppy)3 (fac tris(2-phenylpyridine)iridium), Ir(ppy)2(acac), and Ir(mpyp)3, and conversely, a fluorescent material including Alq3 (tris(8-hydroxyquinoline)aluminum), but are not limited thereto. In the case of the organic light-emitting display device 100 of one embodiment, the first green organic light-emitting layer G_EML1-1 and the second green organic light-emitting layer G_EML1-2 may be formed of the same material.

[0071] The first electron transport layer ETL1 is disposed on the first organic light-emitting layer EML1. The first electron transport layer ETL1 smoothes the transfer of electrons from the charge generation layer 133 to the first organic light-emitting layer EML1. The first electron transport layer ETL1 may be formed together at the red sub-pixel, the blue sub-pixel, the first green sub-pixel, and the second green sub-pixel SPR, SPB, SPG1, and SPG2. Conversely, the first electron transport layers ETL1 of the red sub-pixel, the blue sub-pixel, the first green sub-pixel, and the second green sub-pixel SPR, SPB, SPG1, and SPG2 may be separated from each other. The first electron transport layer ETL1 may be made of any one or more selected from the group consisting of Alq3 (tris(8-hydroxyquinoline)aluminum), PBD, TAZ, spiro-PBD, BAlq, and SAlq, but is not limited thereto.

[0072] A charge generation layer (CGL) 133 is disposed between the first emission portion 132 and the second emission portion 134. The charge generation layer 133 balances the charge between the first organic light-emitting layer EML1 of the first emission portion 132 and the second organic light-emitting layer EML2 of the second emission portion 134. The charge generation layer 133 may include an N-type charge generation layer N-CGL and a P-type charge generation layer P-CGL. The N-type charge generation layer N-CGL injects electrons into the first emission portion 132. The N-type charge generation layer N-CGL may include an N-type dopant and an N-type host material. The P-type charge generation layer P-CGL injects holes into the second emission portion 134. The P-type charge generation layer P-CGL is disposed on the N-type charge generation layer N-CGL and is configured to be coupled to the N-type charge generation layer N-CGL.

[0073] The second emission portion 134 is disposed on the charge generation layer 133. The second emission portion 134 includes a second hole transport layer HTL2, second auxiliary hole transport layers R'HTL2, G'HTL2, B'HTL2, a second organic light emitting layer EML2, a second electron transport layer ETL2 and an electron injection layer EIL.

[0074] The second hole transport layer HTL2 smoothly injects holes from the charge generation layer 133 into the second organic light-emitting layer EML2. The second hole transport layer HTL2 can be formed in common at the red sub-pixel, blue sub-pixel, first green sub-pixel, and second green sub-pixel SPR, SPB, SPG1, and SPG2. The second hole transport layer HTL2 can be made of the same material as the first hole transport layer HTL1 and perform the same functions as the first hole transport layer HTL1. Therefore, their common features are not described.

[0075] Second auxiliary hole transport layers R'HTL2, G'HTL2, and B'HTL2 are disposed on the second hole transport layer HTL2. The second auxiliary hole transport layers R'HTL2, G'HTL2, and B'HTL2, serving as optical auxiliary layers, adjust the distance between the anode 131 and the cathode 135. Therefore, when light emitted from the second organic light-emitting layer EML2 causes interference between the anode 131 and the cathode 135, luminous efficiency can be improved due to the microcavity effect. Furthermore, the second auxiliary hole transport layers R'HTL2, G'HTL2, and B'HTL2 can block electrons in the second organic light-emitting layer EML2 from migrating to the second hole transport layer HTL2.

[0076] The second auxiliary hole transport layers R'HTL2, G'HTL2, and B'HTL2 can be formed at the red sub-pixel, the blue sub-pixel, the first green sub-pixel, and the second green sub-pixel SPR, SPB, SPG1, and SPG2. Specifically, the second auxiliary hole transport layers R'HTL2, G'HTL2, and B'HTL2 include a second red auxiliary hole transport layer R'HTL2 disposed at the red sub-pixel SPR, a second blue auxiliary hole transport layer B'HTL2 disposed at the blue sub-pixel SPB, and a second green auxiliary hole transport layer G'HTL2 disposed at the first green sub-pixel SPG1. In this case, the second blue auxiliary hole transport layer B'HTL2 and the second green auxiliary hole transport layer G'HTL2 are disposed at the second green sub-pixel SPG2.

[0077] Since the second red auxiliary hole transport layer R'HTL2 adjusts the optical distance required for emitting red light at the second emission portion 134, the thickness of the second red auxiliary hole transport layer R'HTL2 can be adjusted according to the wavelength of light emitted from the second red organic light-emitting layer R_EML2. In this case, the thickness of the second red auxiliary hole transport layer R'HTL2 of the red sub-pixel SPR can be greater than the thickness of the second green auxiliary hole transport layer G'HTL2 of the first green sub-pixel SPG1 and the thickness of the second blue auxiliary hole transport layer B'HTL2 of the blue sub-pixel SPB, but is not limited thereto.

[0078] Since the second green auxiliary hole transport layer G'HTL2 adjusts an optical distance required to emit green light at the second emission portion 134 , its thickness is adjusted according to the wavelength of light emitted from the second green organic light emitting layer G_EML1 - 2 .

[0079] The highest occupied molecular orbital (HOMO) energy level of the second green auxiliary hole transport layer G'HTL2 may be -5.1 to -5.3 or -5.1 to -5.2. In addition, the hole mobility of the second green auxiliary hole transport layer G'HTL2 may be 10 -5 to 10- 3 cm 2 When the HOMO energy level and hole mobility of the second green auxiliary hole transport layer G'HTL2 meet the above ranges, the second green auxiliary hole transport layer G'HTL2 can be provided together with the blue auxiliary hole transport layer B'HTL2, so that the luminous efficiency and life of the light emitting diode are improved.

[0080] Since the second blue auxiliary hole transport layer B'HTL2 adjusts the optical distance required to emit blue light at the second emission portion 134, the thickness of the second blue auxiliary hole transport layer B'HTL2 is adjusted according to the wavelength of the light emitted from the second blue organic light-emitting layer B_EML2. In addition, the second blue auxiliary hole transport layer B'HTL2 can block the electrons in the second organic light-emitting layer B_EML2 of the blue sub-pixel SPB from moving to the second hole transport layer HTL2. The second blue auxiliary hole transport layer B'HTL2 can be made of the same material as the first auxiliary hole transport layer B'HTL1 and perform the same function as the first auxiliary hole transport layer B'HTL1. Therefore, their common features are not described. In the case of the second blue auxiliary hole transport layer B'HTL2, the HOMO energy level can be -5.4 to -5.3. In addition, the hole mobility of the second blue auxiliary hole transport layer B'HTL2 can be 5×10 -8 to 5×10 -7 cm 2 / Vs. At this time, the HOMO energy level of the second blue auxiliary hole transport layer B'HTL2 can be greater than the HOMO energy level of the second green auxiliary hole transport layer G'HTL2, and the hole mobility is less than the hole mobility of the second green auxiliary hole transport layer G'HTL2. When the HOMO energy level and hole mobility of the second blue auxiliary hole transport layer B'HTL2 meet the above ranges, the second blue auxiliary hole transport layer B'HTL2 can be provided together with the second green auxiliary hole transport layer G'HTL2, so that the luminous efficiency and life of the light-emitting diode are improved.

[0081] In addition, the second green auxiliary hole transport layer G'HTL2 provided at the first green sub-pixel SPG1 and the second blue auxiliary hole transport layer B'HTL2 provided at the blue sub-pixel SPB are provided at the second green sub-pixel SPG2. That is, the second green auxiliary hole transport layer G'HTL2 and the second blue auxiliary hole transport layer B'HTL2 are continuously stacked between the second hole transport layer HTL2 and the fourth green organic light-emitting layer G_EML2-2. The second green auxiliary hole transport layer G'HTL2 adjusts the optical distance required to emit green light at the second emission portion 134 of the second green sub-pixel SPG2. In addition, the second blue auxiliary hole transport layer B'HTL2 can block electrons in the fourth green organic light-emitting layer G_EML2-2 of the blue sub-pixel SPB from moving to the second hole transport layer HTL2. The thickness of the second green auxiliary hole transport layer G'HTL2 and the thickness of the second blue auxiliary hole transport layer B'HTL2 may be 200 Å and 800 Å, respectively. to and to But it’s not limited to this.

[0082] Because the second green sub-pixel SPG2 further includes a second blue auxiliary hole transport layer B'HTL2 between the second hole transport layer HTL2 and the fourth green organic light-emitting layer G_EML2-2, the optical path of the fourth green organic light-emitting layer G_EML2-2 of the second green sub-pixel SPG2 is different from the optical path of the third green organic light-emitting layer G_EML2-1 of the first green sub-pixel SPG1, compared to the first green sub-pixel SPG1. Therefore, the second green sub-pixel SPG2 has different light-emitting characteristics from the first green sub-pixel SPG1. In other words, the second green sub-pixel SPG2 and the first green sub-pixel SPG1 have different light-emitting efficiencies, different driving voltages, and different brightness characteristics.

[0083] Specifically, since the second green sub-pixel SPG2 includes the second blue auxiliary hole transport layer B'HTL2 with the function of blocking electrons, under the fourth green organic light-emitting layer G_EML2-2 of the second emission portion 134, the electrons in the fourth green organic light-emitting layer G_EML2-2 of the second green sub-pixel SPG2 can be blocked from moving to the second hole transport layer HTL2, thereby preventing the life of the organic light-emitting diode 130 from deteriorating and improving the light-emitting efficiency.

[0084] For each of the red, blue, first, and second green sub-pixels SPR, SPB, SPG1, and SPG2, a second organic light-emitting layer EML2 is formed on the first auxiliary hole transport layer B'HTL1. Specifically, a second red organic light-emitting layer R_EML2 is formed at the red sub-pixel SPR, a second blue organic light-emitting layer B_EML2 is formed at the blue sub-pixel SPB, a third green organic light-emitting layer G_EML2-1 is formed at the first green sub-pixel SPG1, and a fourth green light-emitting layer G_EML2-2 is formed at the second green sub-pixel SPG2. Each second organic light-emitting layer EML2 may have a different thickness. The second organic light-emitting layer EML2 may be made of the same material as the first organic light-emitting layer EML1 and perform the same functions as the first organic light-emitting layer EML1. Therefore, their common features are not described here.

[0085] A second electron transport layer (ETL2) is disposed on the second organic light-emitting layer (EML2). The second electron transport layer (ETL2) smoothes the transmission of electrons from the cathode 135 to the second organic light-emitting layer (EML2). The second electron transport layer (ETL2) can be formed on the red sub-pixel, the blue sub-pixel, the first green sub-pixel, and the second green sub-pixel (SPR, SPB, SPG1, SPG2). The second electron transport layer (ETL2) can be made of the same material as the first electron transport layer (ETL1) and perform the same functions as the first electron transport layer (ETL1). Therefore, their common features are not described.

[0086] The electron injection layer (EIL) is disposed on the second electron transport layer (ETL) 2. The electron injection layer (EIL) smoothes the injection of electrons from the cathode 135 into the plurality of organic layers (OL). The electron injection layer (EIL) may be made of, for example, one or more materials including, but not limited to, LiF, Al, MoO3, Liq (lithium quinolate), Alq3 (tris(8-hydroxyquinoline)aluminum), PBD, TAZ, spiro-PBD, BAlq, or SAlq.

[0087] A capping layer 140 is formed on the cathode 135. The capping layer 140 is used to protect the organic light-emitting diode 130 and increase the light extraction effect. The capping layer 140 can be made of any of the host materials of the first hole transport layer HTL1, the first electron transport layer ETL1, and the organic light-emitting layer. In addition, the capping layer 140 can be omitted. In addition, the thickness of the capping layer 140 can be 60nm to 90nm.

[0088] In an organic light-emitting display device according to one embodiment, two green sub-pixels with different optical characteristics are included in a pixel. The organic light-emitting display device according to one embodiment includes a red sub-pixel, a blue sub-pixel, a first green sub-pixel, and a second green sub-pixel. Compared to the first green sub-pixel, the second green sub-pixel includes an additional auxiliary hole transport layer, thereby changing the overall height of the diode and the optical area of ​​the organic light-emitting layer. Therefore, the second green sub-pixel has different optical characteristics from the first green sub-pixel.

[0089] Specifically, each of the red sub-pixel, the blue sub-pixel, the first green sub-pixel and the second green sub-pixel includes a light-emitting diode of a double-stack structure, and the double-stack structure includes a first emission part and a second emission part. The first auxiliary hole transport layer is arranged at the first emission part of the blue sub-pixel and the second green sub-pixel to smooth the injection of holes into the organic light-emitting layer and prevent electrons from crossing the hole transport layer. At the same time, the second green auxiliary hole transport layer arranged at the second emission part of the first green sub-pixel and the second blue auxiliary hole transport layer arranged at the second emission part of the blue sub-pixel are arranged at the second emission part of the second green sub-pixel to block electrons from overflowing from the organic light-emitting layer and adjust the optical path. Therefore, the second green sub-pixel can ensure that the luminous efficiency and brightness are greater than the luminous efficiency and brightness of the first green sub-pixel, and exhibits a luminous characteristic that causes a reduction in driving voltage.

[0090] Green sub-pixels typically exhibit significant rise and fall delay characteristics when turned on and off, and residual charge in the green sub-pixel when operating may cause unexpected emission of light or afterimages. This is particularly prominent during low-level driving. However, in an organic light-emitting display device in one embodiment, since a second green sub-pixel having a greater luminous property than the first green sub-pixel is provided simultaneously with the first green sub-pixel, the second green sub-pixel having excellent luminescence emits light first during low-grayscale driving, solving the problem during low-grayscale driving.

[0091] In addition, in the case of a light-emitting diode using a microcavity effect, the light path on the front surface and the light path on the side surface may be different, so that the wavelength of the light causing the resonance changes. Therefore, on the side surface with a large viewing angle, rather than on the front surface, the light path is relatively elongated, and the wavelength of the resonant light shifts to a short wavelength, and the brightness deteriorates. In particular, in the case where the green sub-pixel is designed to have a smaller light-emitting surface area than the red sub-pixel and the blue sub-pixel for high emission brightness, the degradation of the brightness can be further emphasized based on the change in the viewing angle of the green sub-pixel. However, in an organic light-emitting display device of one embodiment, since a first green sub-pixel and a second green sub-pixel having different optical characteristics are provided at the same time, the brightness degradation based on the viewing angle can be solved.

[0092] While the number of processes increases when dopants of the light-emitting layer are used differently to form two sub-pixels with different light-emitting characteristics, in an organic light-emitting display device according to one embodiment, a first hole-assisting transport layer provided at a blue sub-pixel and a second hole-assisting transport layer are simultaneously formed at a second green sub-pixel. Therefore, light-emitting diodes having first and second green sub-pixels with different emission characteristics can be formed without adding a separate process.

[0093] In addition, for the same green sub-pixel emitting light with different luminescence characteristics, two identical green sub-pixels need to be driven separately. This requires additional wiring and drivers, complicating the manufacturing process and driving method. However, in an organic light-emitting display device of one embodiment, even when a first and a second green sub-pixel are driven simultaneously using first and second green light-emitting diodes with different luminescence characteristics, the second green sub-pixel emits light earlier than the first green sub-pixel, making it easy to distinguish low-grayscale afterimages.

[0094] Furthermore, in an organic light-emitting display device according to one embodiment, since the emission efficiency of the second green sub-pixel is greater than that of the first green sub-pixel, the emission surface area of ​​the second green sub-pixel can be smaller than that of the first green sub-pixel. As the emission surface area of ​​the second green sub-pixel decreases, the emission surface area of ​​another sub-pixel (e.g., the emission surface area of ​​the blue sub-pixel) can increase, thereby improving the lifespan of the entire display device. For example, unlike conventional pixel arrangements, the emission surface area of ​​the blue sub-pixel can be increased by 5% or 10%.

[0095] Hereinafter, the effects produced by the configuration of the adhesive layer will be specifically described with reference to Examples and Comparative Examples. However, the following Examples are provided as examples and are not intended to limit the scope of the present disclosure.

[0096] Experimental Example 1

[0097] The performance of the diode was evaluated in the absence and presence of the second green auxiliary hole transport layer of the second green sub-pixel.

[0098] In the Figure 3 In the embodiment 1 of the organic light emitting display device shown in FIG, the first light emitting portion of the second green sub-pixel includes a first auxiliary hole transport layer (B'HTL1; HOMO energy level: -5.33; hole mobility: 1.0×10 -7 cm 2 / Vs), thickness is The second emission portion of the second green sub-pixel includes a second green auxiliary hole transport layer (G'HTL2; HOMO energy level: -5.13; hole mobility: 1.3×10 -4 cm2 / Vs), thickness is and the second blue auxiliary hole transport layer (B'HTL2; HOMO energy level: -5.33; hole mobility: 1.0×10 -7 cm 2 / Vs), thickness is

[0099] Comparative Example 1 has the same structure as Embodiment 1, except that the comparative example does not include the first auxiliary hole transport layer and the second blue auxiliary hole transport layer.

[0100] exist Figure 4 In FIG. 1 , the current density characteristics are compared based on the driving voltage of the green sub-pixel in Comparative Example 1 and Example 1. FIG. Figure 4 Graph showing current density characteristics of driving voltage of the green sub-pixel according to Comparative Example 1 and Example 1 of the present disclosure.

[0101] Reference Figure 4 , when the first auxiliary hole transport layer and the second blue auxiliary hole transport layer serving as electron blocking layers are respectively disposed at the first emission portion and the second emission portion of the second green sub-pixel, the current density may increase and the driving voltage may decrease.

[0102] In Table 1 below, the driving voltage V, luminous efficiency cd / A and lifetime of the diodes in Example 1 and Comparative Example 1 were measured, and then changes in the driving voltage, efficiency and lifetime in Example 1 are shown relative to Comparative Example 1.

[0103] [Table 1]

[0104] Driving voltage change Efficiency changes Lifespan changes Comparative Example 1 - - - Example 1 Reduce 0.08V 3% increase 26% increase

[0105] Referring to Table 1, compared with Comparative Example 1, the driving voltage in Example 1 is reduced, whereas compared with Comparative Example 1, the luminous efficiency and lifespan of the diode in Example 1 are increased.

[0106] Experimental Example 2

[0107] The luminous efficiency was evaluated based on the varying position and thickness of the second green auxiliary hole transport layer of the second green sub-pixel.

[0108] Comparative Example 2 has the same structure as Example 1, except that the second green auxiliary hole transport layer (G'HTL2; HOMO energy level: -5.13; hole mobility: 1.3×10 -4 cm 2 / Vs) is disposed on the first hole transport layer HTL1 of the first emission portion 132 instead of the second emission portion 134 .

[0109] In Table 2 below, luminous efficiency is evaluated based on the varying thickness of the second green auxiliary hole transport layer of the second green sub-pixel disposed at the second emission portion or the first emission portion in Example 1 and Comparative Example 2, respectively.

[0110] [Table 2]

[0111]

[0112] Figure 5 : is a graph showing the light efficiency characteristics depending on the thickness of the second green auxiliary hole transport layer of the second green sub-pixel in Example 1 and Comparative Example 2. That is, Figure 5 It is a graph of Table 2. Referring to Table 2, when the thickness of the second green auxiliary hole transport layer of the second green sub-pixel is 20-40 nm, the luminous efficiency is significantly improved. Figure 5 , when the second green auxiliary hole transport layer is provided in the second emission part instead of the first emission part, the luminous efficiency is improved by about 17% based on the results measured at the thickness of the green auxiliary hole transport layer that ensures the maximum efficiency.

[0113] Exemplary embodiments of the present disclosure may also be described as follows:

[0114] According to one aspect of the present disclosure, an organic light-emitting display device is provided. The organic light-emitting display device includes: a substrate on which a red sub-pixel, a blue sub-pixel, a first green sub-pixel, and a second green sub-pixel are arranged; an anode, which is respectively arranged at each of the red sub-pixel, the blue sub-pixel, the first green sub-pixel, and the second green sub-pixel; a first hole transport layer arranged on the anode; a first auxiliary hole transport layer arranged on the first hole transport layer at the blue sub-pixel and the second green sub-pixel; a first red organic light-emitting layer, a first blue organic light-emitting layer, a first green organic light-emitting layer, and a second green organic light-emitting layer, which are respectively arranged at the red sub-pixel, the blue sub-pixel, the first green sub-pixel, and the second green sub-pixel; a charge generation layer disposed on the red organic light-emitting layer, the blue organic light-emitting layer, the first green organic light-emitting layer, and the second green organic light-emitting layer; a second auxiliary hole transport layer disposed on the charge generation layer; a second red organic light-emitting layer, a second blue organic light-emitting layer, a third green organic light-emitting layer, and a fourth green organic light-emitting layer disposed on the second auxiliary hole transport layer at each of the red sub-pixel, the blue sub-pixel, the first green sub-pixel, and the second green sub-pixel; an electron transport layer disposed on the second red organic light-emitting layer, the second blue organic light-emitting layer, the third green organic light-emitting layer, and the fourth green organic light-emitting layer; and a cathode disposed on the electron transport layer. The second auxiliary hole transport layer includes a second green auxiliary hole transport layer and a second blue auxiliary hole transport layer disposed at the second green sub-pixel.

[0115] At the second green sub-pixel, a second blue auxiliary hole transport layer may be disposed on the second green auxiliary hole transport layer.

[0116] The second auxiliary hole transport layer may further include a second red auxiliary hole transport layer disposed at the red sub-pixel, a second green auxiliary hole transport layer may be disposed at the first green sub-pixel and the second green sub-pixel, and a second blue auxiliary hole transport layer may be disposed at the blue sub-pixel and the second green sub-pixel.

[0117] The first auxiliary hole transport layer and the second blue auxiliary hole transport layer may be made of the same material.

[0118] The first auxiliary hole transport layer and the second blue auxiliary hole transport layer may include a trofluorene compound, at least a portion of which is substituted with deuterium.

[0119] The second blue auxiliary hole transport layer may have a larger HOMO energy level and a smaller hole mobility than those of the second green auxiliary hole transport layer.

[0120] The optical path of the second green organic light-emitting layer of the second green sub-pixel may be greater than the optical path of the first green organic light-emitting layer of the first green sub-pixel, and the optical path of the fourth green organic light-emitting layer of the second green sub-pixel may be greater than the optical path of the third green organic light-emitting layer of the first green sub-pixel.

[0121] A light emitting surface area of ​​the second green sub-pixel may be larger than a light emitting surface area of ​​the first green sub-pixel.

[0122] The light emitting efficiency of the second green sub-pixel may be greater than the light emitting efficiency of the first green sub-pixel.

Claims

1. An organic light-emitting display device, comprising: a substrate on which a red sub-pixel, a blue sub-pixel, a first green sub-pixel and a second green sub-pixel are disposed; an anode, which is respectively provided at each of the red sub-pixel, the blue sub-pixel, the first green sub-pixel, and the second green sub-pixel; a first hole transport layer disposed on the anode; A first red organic light-emitting layer, a first blue organic light-emitting layer, a first green organic light-emitting layer, and a second green organic light-emitting layer are respectively provided at the red sub-pixel, the blue sub-pixel, the first green sub-pixel, and the second green sub-pixel; a charge generation layer disposed on the red organic light-emitting layer, the blue organic light-emitting layer, the first green organic light-emitting layer, and the second green organic light-emitting layer; an electron transport layer disposed on the charge generation layer; as well as A cathode disposed on the electron transport layer, Compared with the first green sub-pixel, the second green sub-pixel includes an additional auxiliary hole transport layer, and the auxiliary hole transport layer includes a first auxiliary hole transport layer arranged between the hole transport layer and the charge generation layer at the second green sub-pixel, and / or a second auxiliary hole transport layer arranged between the charge generation layer and the electron transport layer at the second green sub-pixel, so that the second green sub-pixel has greater luminescence characteristics than the first green sub-pixel. 2 . The organic light emitting display device according to claim 1 , wherein the luminous efficiency and brightness of the second green sub-pixel are greater than the luminous efficiency and brightness of the first green sub-pixel.

3. An organic light-emitting display device, comprising: a substrate on which a red sub-pixel, a blue sub-pixel, a first green sub-pixel and a second green sub-pixel are disposed; an anode, which is respectively provided at each of the red sub-pixel, the blue sub-pixel, the first green sub-pixel, and the second green sub-pixel; a first hole transport layer disposed on the anode; a first auxiliary hole transport layer disposed on the first hole transport layer at the blue sub-pixel and the second green sub-pixel; A first red organic light-emitting layer, a first blue organic light-emitting layer, a first green organic light-emitting layer, and a second green organic light-emitting layer are respectively provided at the red sub-pixel, the blue sub-pixel, the first green sub-pixel, and the second green sub-pixel; a charge generation layer disposed on the red organic light-emitting layer, the blue organic light-emitting layer, the first green organic light-emitting layer, and the second green organic light-emitting layer; a second auxiliary hole transport layer disposed on the charge generation layer; a second red organic light-emitting layer, a second blue organic light-emitting layer, a third green organic light-emitting layer, and a fourth green organic light-emitting layer disposed on the second auxiliary hole transport layer at each of the red sub-pixel, the blue sub-pixel, the first green sub-pixel, and the second green sub-pixel; an electron transport layer disposed on the second red organic light-emitting layer, the second blue organic light-emitting layer, the third green organic light-emitting layer, and the fourth green organic light-emitting layer; as well as A cathode disposed on the electron transport layer, The second auxiliary hole transport layer includes a second green auxiliary hole transport layer and a second blue auxiliary hole transport layer provided at the second green sub-pixel. 4 . The organic light emitting display device according to claim 3 , wherein at the second green sub-pixel, the second blue auxiliary hole transport layer is disposed on the second green auxiliary hole transport layer.

5. The organic light emitting display device according to claim 4, wherein the second auxiliary hole transport layer further comprises a second red auxiliary hole transport layer disposed at the red sub-pixel, The second green auxiliary hole transport layer is disposed at the first green sub-pixel and the second green sub-pixel, and The second blue auxiliary hole transport layer is disposed at the blue sub-pixel and the second green sub-pixel. 6 . The organic light emitting display device according to claim 3 , wherein the first auxiliary hole transport layer and the second blue auxiliary hole transport layer are made of the same material. 7 . The organic light emitting display device according to claim 3 , wherein the first auxiliary hole transport layer and the second blue auxiliary hole transport layer comprise a trofluorene compound, at least a portion of which is substituted with deuterium. 8 . The organic light emitting display device according to claim 3 , wherein the second blue auxiliary hole transport layer has a larger HOMO energy level and a smaller hole mobility than the second green auxiliary hole transport layer.

9. The organic light emitting display device according to claim 3, wherein the optical distance of the second green organic light emitting layer of the second green sub-pixel is greater than the optical distance of the first green organic light emitting layer of the first green sub-pixel, and An optical distance of the fourth green organic light-emitting layer of the second green sub-pixel is greater than an optical distance of the third green organic light-emitting layer of the first green sub-pixel. 10 . The organic light emitting display device according to claim 3 , wherein a light emitting surface area of ​​the second green sub-pixel is larger than a light emitting surface area of ​​the first green sub-pixel. 11 . The organic light emitting display device according to claim 3 , wherein a light emitting efficiency of the second green sub-pixel is greater than a light emitting efficiency of the first green sub-pixel. 12 . The organic light emitting display device according to claim 1 , wherein the red sub-pixel, the blue sub-pixel, and the first green sub-pixel are arranged in a pentile structure. 13 . The organic light-emitting display device according to claim 3 , wherein a thickness of the second red auxiliary hole transport layer is greater than a thickness of the second green auxiliary hole transport layer and a thickness of the second blue auxiliary hole transport layer. 14 . The organic light-emitting display device according to claim 3 , further comprising a second hole transport layer disposed on the charge generation layer, wherein the second auxiliary hole transport layer is disposed on the second hole transport layer. 15 . The organic light emitting display device according to claim 3 , further comprising a capping layer disposed on the cathode.

Images