Organic Light Emitting Display Device

Abstract

To provide an organic light-emitting display device with improved perceived image quality.SOLUTION: An organic light-emitting display device includes a display panel containing a plurality of sub-pixels, an organic light emitting element provided in each of the plurality of sub-pixels, and a color shift suppression structure on the top of the organic light emitting element.SELECTED DRAWING: Figure 5

Description

[Technical field]

[0001] The present specification relates to an organic light emitting display device. [Background technology]

[0002] Image display devices that display various information on a screen are a core technology in the information and communication era, and are evolving toward thinner, lighter, more portable, and more powerful devices. As a result, organic light-emitting display devices that display images by controlling the amount of light emitted by organic light-emitting elements are gaining attention.

[0003] An organic light emitting device is a self-emitting device using a thin light emitting layer between electrodes, and has the advantage of being thin-filmable. A typical organic light emitting display device has a structure in which a pixel driving circuit and an organic light emitting device are formed on a substrate, and light emitted from the organic light emitting device passes through the substrate or a barrier layer to display an image.

[0004] Since an organic light emitting display device can be implemented without a separate light source device, it is easy to implement it as a flexible display device. Flexible materials such as plastic and metal foil can be used as a substrate of the organic light emitting display device. Summary of the Invention [Problem to be solved by the invention]

[0005] Organic light emitting display devices are being developed to provide optimal user experience depending on the environment. In particular, there is a tendency for them to be designed so that users can feel the best image quality under various environments and usage conditions. Therefore, an object of the present specification is to improve the perceived image quality of an organic light emitting display device. The object of the present specification is not limited to the object described above, and other object not mentioned will be clearly understood by those skilled in the art from the following description. [Means for solving the problem]

[0006] According to an embodiment of the present disclosure, an organic light emitting display device is provided, the organic light emitting display device may include an organic light emitting device provided in each of a plurality of sub-pixels, and a color shift suppression structure provided on an upper portion of the organic light emitting device.

[0007] The color shift suppression structure may include a first cover layer on the organic light emitting device and a second cover layer on the first cover layer, and the second cover layer may be provided differently for each of the sub-pixels.

[0008] The first cover layer may be an organic film and the second cover layer may be an inorganic film.

[0009] The first cover layer may be in contact with an upper portion of the cathode of the organic light emitting device.

[0010] The second cover layer may have the same shape as the anode of the organic light emitting device, and the area of ​​the second cover layer may be 50% to 90% of the area of ​​the anode. Also, the area of ​​the second cover layer may be wider as the wavelength of light emitted from the corresponding sub-pixel is shorter.

[0011] The area of ​​the second cover layer corresponding to the subpixels emitting blue light may be larger than the area of ​​the second cover layer corresponding to the subpixels emitting green light, and the area of ​​the second cover layer corresponding to the subpixels emitting green light may be larger than the area of ​​the second cover layer corresponding to the subpixels emitting red light.

[0012] The second cover layer may be hemispherical, and the interface where the first cover layer and the second cover layer contact each other may have a roughness equal to or greater than a predetermined value.

[0013] The organic light emitting display device may have a first region including a first ratio of sub-pixels not having the second cover layer thereon and a second region including a second ratio of sub-pixels not having the second cover layer thereon, the second ratio being greater than the first ratio, wherein a second viewing angle at which a user views the second region may be greater than a first viewing angle at which a user views the first region.

[0014] Further details of the embodiments are included in the detailed description and the drawings. Effect of the Invention

[0015] The embodiments of the present specification may provide an organic light emitting display device in which the problem of degradation of perceived image quality is improved. More specifically, the embodiments of the present specification may reduce the influence of the viewing angle of the organic light emitting display device on the perceived image quality. As a result, the organic light emitting display device according to the embodiments of the present specification may be improved in usability in various environments. The effects of the embodiments of the present specification are not limited to the above examples, and various other effects are included in the present specification. [Brief description of the drawings]

[0016] [Figure 1] 1 is a plan view illustrating an organic light emitting display device according to an embodiment of the present disclosure; [Diagram 2] 1 is a cross-sectional view showing a portion of a display area of ​​an organic light emitting display device according to an embodiment of the present disclosure; [Diagram 3] 1 is a diagram illustrating a portion of a non-display area of ​​an organic light emitting display device according to an embodiment of the present disclosure; [Figure 4] 1 is a diagram illustrating a sub-pixel of an organic light emitting display device according to an embodiment of the present disclosure; [Diagram 5] 1 is a diagram illustrating a sub-pixel of an organic light emitting display device according to another embodiment of the present disclosure. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0017] The advantages and features of the present specification, and the methods for achieving them, will become clear with reference to the following detailed description of the embodiments together with the accompanying drawings. However, the present specification is not limited to the embodiments disclosed below, and may be realized in various different forms. The embodiments are merely provided to complete the disclosure of the specification and to fully inform those skilled in the art of the invention to which the specification pertains, and the specification is defined only by the scope of the claims.

[0018] In order to explain the embodiments of the present specification, the shapes, sizes, ratios, angles, numbers, etc. shown in the drawings are illustrative and the present specification is not limited to the matters shown in the drawings. The same reference symbols refer to the same components throughout the specification. In addition, in explaining this specification, if a specific description of related known technology is judged to unnecessarily obscure the gist of the present invention, the detailed description will be omitted. When "including," "having," "consisting of," etc. are used in this specification, other parts can be added unless "only" is used. When a component is expressed in the singular, it is interpreted as including a plural number unless otherwise expressly stated.

[0019] In the case of describing a positional relationship, for example, when the positional relationship of two parts is described using "on", "on top of", "on bottom of", "next to", etc., one or more other parts may be located between the two parts, unless "immediately" or "directly" is used. The term "on" an element or layer includes all cases where an element or layer is directly on or in between another device with other layers or elements interposed therebetween. When a component is described as being "coupled", "bonded" or "connected" to another component, it should be understood that the component may be directly coupled or connected to the other component, and that there may be other components "intervening" between each component, or each component may be "coupled", "bonded" or "connected" via another component.

[0020] 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 merely used to distinguish one component from another. Therefore, the first component referred to below may be the second component within the technical concept of the present invention.

[0021] The size and thickness of each component shown in the drawings are shown for convenience of explanation, and the present invention is not necessarily limited to the size and thickness of the components shown. Various embodiments of the present invention will be described in detail below with reference to the attached drawings.

[0022] FIG. 1 is a plan view showing an organic light-emitting display device according to an embodiment of the present specification.

[0023] Referring to FIG. 1, the OLED display 100 includes at least one active area (A / A), and an array of pixels is arranged in the active area. One pixel may include a plurality of sub-pixels. Here, a sub-pixel is the smallest unit for expressing one color. One sub-pixel circuit may include a plurality of transistors, a capacitor, and a plurality of wirings. The sub-pixel circuit may be composed of two transistors and a capacitor (2T1C), but is not limited thereto, and may be implemented as a sub-pixel circuit using 4T1C, 7T1C, 6T2C, etc. Also, the sub-pixel may be implemented to be compatible with the OLED display 100 of a top-emission type.

[0024] One or more inactive areas (I / A) may be arranged around the display area. That is, the inactive areas may be adjacent to one or more sides of the display area. In FIG. 1, the inactive area surrounds a rectangular display area. However, the shape of the display area and the shape / arrangement of the inactive areas adjacent to the display area are not limited to the example shown in FIG. 1. The display area and the inactive area may have a shape suitable for the design of an electronic device equipped with the display device 100. Exemplary shapes of the display area include a pentagon, a hexagon, a circle, an ellipse, etc.

[0025] Each pixel in the display area (A / A) can be associated with a pixel circuit. The pixel circuit can include one or more switching transistors and one or more driving transistors. Each pixel circuit can be electrically connected to a signal line (e.g., gate line, data line, etc.) for communication with a gate driver, a data driver, etc. located in the non-display area.

[0026] The gate driver and the data driver may be implemented as thin film transistors (TFTs) in the non-display area (I / A). Such a driver may be called a gate-in-panel (GIP). Also, some components such as a data driver IC may be mounted on a separate printed circuit board and coupled to a connection interface (pad, bump, pin, etc.) arranged in the non-display area through a circuit film such as a flexible printed circuit board (FPCB), chip-on-film (COF), tape-carrier-package (TCP), etc. The printed circuit (COF, PCB, etc.) may be formed on the display device 100. It can be located behind the

[0027] The OLED display 100 may include various additional elements for generating various signals and driving pixels in a display area. The additional elements for driving pixels may include an inverter circuit, a multiplexer, an electrostatic discharge (ESD) circuit, etc. The OLED display 100 may also include additional elements associated with functions other than pixel driving. For example, the OLED display 100 may include additional elements providing a touch detection function, a user authentication function (e.g., fingerprint), a multi-level pen pressure function, a tactile feedback function, etc. The additional elements may be located in the non-display area and / or an external circuit connected to the connection interface.

[0028] FIG. 2 is a cross-sectional view showing a part of a display area of ​​an organic light emitting display device according to an embodiment of the present disclosure.

[0029] The organic light emitting display device 100 may include a substrate 101, a thin film transistor, an organic light emitting device, and various functional layers.

[0030] The substrate 101 serves to support and protect components of the OLED display 100 disposed thereon. The substrate 101 may be a flexible substrate made of a soft material having a flexible property. The substrate 101 may be a glass or plastic substrate. In the case of a plastic substrate, it may have flexibility by using a polyimide-based or polycarbonate-based material. In particular, polyimide is widely used for plastic substrates since it can be applied to high temperature processes and is a material that can be coated.

[0031] The buffer layer 103 is a functional layer for protecting the electrodes / wirings from impurities such as alkali ions flowing out from the substrate 101 or a lower layer. The buffer layer may be made of silicon oxide (SiOx), silicon nitride (SiNx), or a multi-layer thereof. The buffer layer 103 may include a multi-buffer and / or an active buffer. The multi-buffer may be formed by alternately stacking silicon nitride (SiNx) and silicon oxide (SiOx) and may delay the diffusion of moisture and / or oxygen that has penetrated into the substrate 101. The active buffer protects the semiconductor layer 102 of the transistor and blocks various types of defects flowing in from the substrate 101. The active buffer may be formed of amorphous silicon (a-Si), etc.

[0032] The thin film transistor includes a gate electrode 104, a source and drain electrodes 108, and a semiconductor layer 102. The semiconductor layer 102 can be made of amorphous silicon or polycrystalline silicon. Polycrystalline silicon has better mobility than amorphous silicon, has lower energy consumption, and is highly reliable. Recently, oxide semiconductors have been in the limelight due to their excellent mobility and uniformity. The semiconductor layer 102 can include a source region containing p-type or n-type impurities, a drain region, and a channel between the source region and the drain region, and can include a low-concentration doping region between the channel and the adjacent source region and drain region.

[0033] The gate insulating layer 105 is an insulating film made up of a single layer or multiple layers of silicon oxide (SiOx) or silicon nitride (SiNx), and is provided so that a current flowing through the semiconductor layer 102 does not flow through the gate electrode 104.

[0034] The gate electrode 104 acts as a switch that turns on or off the thin film transistor based on an electrical signal transmitted from the outside through the gate line, and may be formed of a single layer or multiple layers of conductive metals such as copper (Cu), aluminum (Al), molybdenum (Mo), chromium (Cr), gold (Au), titanium (Ti), nickel (Ni), and neodymium (Nd), or alloys thereof. The source and drain electrodes 108 are connected to the data line, and transmit electrical signals transmitted from the outside from the thin film transistor to the organic light emitting element. The source and drain electrodes 108 may be formed of a single layer or multiple layers of conductive metals such as copper (Cu), aluminum (Al), molybdenum (Mo), chromium (Cr), gold (Au), titanium (Ti), nickel (Ni), and neodymium (Nd), or alloys thereof.

[0035] In order to insulate the gate electrode 104 and the source and drain electrodes 108 from each other, an interlayer insulating layer 106 composed of a single layer or multiple layers of silicon oxide (SiOx) or silicon nitride (SiNx) can be disposed between the gate electrode 104 and the source and drain electrodes 108.

[0036] A protective layer made of an inorganic insulating film such as silicon oxide (SiOx) or silicon nitride (SiNx) may be positioned on the thin film transistor. The protective layer may prevent unnecessary electrical connection between components of the thin film transistor and prevent contamination or damage from the outside. The protective layer may be omitted depending on the configuration and characteristics of the thin film transistor and the organic light emitting device.

[0037] For convenience of explanation, only the driving thin film transistor is shown in the figure among various thin film transistors, but the switching thin film transistor, capacitor, etc. may also be included in the display area. When a signal is applied from the gate line, the switching thin film transistor transmits a signal from the data line to the gate electrode of the driving thin film transistor. The driving thin film transistor transmits a current distributed through the power supply wiring to the anode according to the signal transmitted from the switching thin film transistor, and light emission is controlled by the current transmitted to the anode.

[0038] A planarization layer 109 is disposed on the thin film transistor. The planarization layer 109 protects the thin film transistor, reduces steps caused by the thin film transistor, and reduces parasitic capacitance generated between the thin film transistor and the gate line, data line, and organic light emitting element. The planarization layer 109 may be formed of one or more materials selected from the group consisting of acrylic resin, epoxy resin, phenolic resin, polyamide resin, polyimide resin, unsaturated polyester resin, polyphenylene resin, polyphenylenesulfides resin, and benzocyclobutene.

[0039] The organic light emitting element is disposed on the planarization layer 109. The organic light emitting element includes an anode 112, a light emitting portion 114, and a cathode 116. The organic light emitting element may be configured as a single light emitting portion structure that emits one light, or may be configured as a structure in which a plurality of light emitting portions are stacked to emit white light. When the organic light emitting element emits white light, a color filter may be provided. The anode 112 may be disposed immediately on the planarization layer 109. The anode 112 is an electrode that serves to supply holes to the light emitting portion 114, and may be electrically connected to a thin film transistor through a contact hole in the planarization layer 109. The anode 112 may be configured of a transparent conductive material such as indium tin oxide (ITO) or indium zinc oxide (IZO). In the case where the OLED display 100 is a top emission type, the anode may further include a reflective layer so that the emitted light can be more smoothly emitted toward the top where the cathode 116 is disposed. The anode 112 may have a two-layer structure in which a transparent conductive layer and a reflective layer made of a transparent conductive material are stacked in order, or a three-layer structure in which a transparent conductive layer, a reflective layer, and a transparent conductive layer are stacked in order, and the reflective layer may be made of silver (Ag) or an alloy containing silver.

[0040] The bank 110 is disposed on the anode 112 and the planarization layer 109, and can define an area that actually emits light. The bank 110 is formed by forming a photoresist on the anode 112 and then performing a photolithography process. The photoresist is a photosensitive resin whose solubility in a developer changes depending on the action of light, and a specific pattern can be obtained by exposing and developing the photoresist.

[0041] A deposition mask, FMM (Fine Metal Mask), may be used to form the light emitting portion 114 of the organic light emitting device. Here, in order to prevent damage that may occur due to contact with the deposition mask disposed on the bank 110 and to maintain a certain distance between the bank 110 and the deposition mask, a spacer 111 made of one of transparent organic materials, polyimide, photoacrylic, and benzocyclobutylene (BCB), may be disposed on the upper portion of the bank 110.

[0042] The light emitting unit 114 is disposed between the anode 112 and the cathode 116. The light emitting unit 114 serves to emit light and may include at least one layer selected from the group consisting of a hole injection layer (HIL), a hole transport layer (HTL), an emission layer (EML), an electron transport layer (ETL), and an electron injection layer (EIL). Depending on the structure or characteristics of the OLED display 100, some elements constituting the light emitting unit 114 may be omitted.

[0043] The cathode 116 is disposed on the light emitting portion 114 and serves to supply electrons to the light emitting portion 114. The cathode 116, which must supply electrons, may be made of a metal material having a low work function, such as magnesium (Mg) or silver magnesium (Ag:Mg). When the organic light emitting display device 100 is a top emission type, the cathode 116 may be a transparent conductive oxide such as indium tin oxide (ITO), indium zinc oxide (IZO), indium tin zinc oxide (ITZO), zinc oxide (ZnO), or tin oxide (TiO).

[0044] An encapsulation layer 120 may be disposed on the organic light emitting device to prevent oxidation or damage caused by moisture, oxygen, or impurities from the outside. The encapsulation layer 120 may be formed by stacking a plurality of inorganic layers, a foreign matter compensation layer, and a plurality of barrier films. The inorganic layer may be disposed on the entire upper surface of the organic light emitting device and may be made of one of inorganic materials such as silicon nitride (SiNx) or aluminum oxide (AlyOz). An inorganic layer may be further stacked on the foreign matter compensation layer. The foreign matter compensation layer may be disposed on the inorganic layer and may be made of organic materials such as silicon oxycarbonate (SiOCz), acrylic, or epoxy resin. The foreign matter compensation layer compensates for defects caused by cracks generated by foreign matter or particles that may occur during processing by covering such bends and foreign matter.

[0045] A touch electrode (panel), a polarizing film, a cover glass, etc. may be disposed on the encapsulation layer 120 .

[0046] FIG. 3 is a diagram illustrating a portion of a non-display area of ​​an organic light emitting display device according to an embodiment of the present disclosure.

[0047] As shown in FIG. 1, the non-display area (I / A) may be located on the outer periphery of the display area (A / A), and a driving circuit (e.g., GIP), power wiring, etc. may be disposed thereon. In the non-display area (I / A), pixel circuits and light-emitting elements are not disposed, but the substrate 101 and organic / inorganic functional layers 103, 105, 109, etc. may be present. In addition, the non-display area (I / A) may be disposed with a material used in the configuration of the display area (A / A) for other purposes. For example, the gate metal 104', which is the same as the gate electrode of the display area TFT, or the same metal as the source / drain electrodes, may be disposed in the non-display area (I / A) for wiring or electrodes. In addition, the same metal 112' as one electrode (e.g., anode) of the organic light-emitting diode may be disposed in the non-display area (I / A) for wiring or electrodes.

[0048] The organic light emitting element is covered with an encapsulation layer 120. The encapsulation layer may be made of an inorganic film made of glass, metal, aluminum oxide (AlOx) or silicon (Si)-based material, or may have a structure in which organic and inorganic films are alternately laminated. The inorganic films 121 and 123 function to block the penetration of moisture and oxygen, and the organic film 122 functions to flatten the surface of the inorganic film 121.

[0049] The organic film 122 has a certain degree of fluidity and may flow to the outer periphery of the non-display area during application. Therefore, the dam 190 is arranged to control the spread of the organic film 122 to the non-display area (I / A). Although an example in which two dams are arranged is shown in FIG. 3, the dams may be arranged in other numbers. In addition, the dam 190 may be arranged to surround the display area (A / A) or may be arranged within the display area (A / A). The dam 190 may be formed in multiple layers using at least one or more materials. For example, the dam 190 may be formed using the materials used to form the planarization layer 109, the bank 110, and the spacer 111.

[0050] Various circuits and electrodes / wirings arranged in the non-display area (I / A) can be formed of a gate metal 104' and / or a source / drain metal 108'. Here, the gate metal 104' is formed in the same process and with the same material as the gate electrode of the TFT, and the source / drain metal 108' is formed in the same process and with the same material as the source / drain electrodes of the TFT.

[0051] For example, the source / drain metal 108' can be used for power supply (e.g., low level power supply (VSS), high level power supply (VDD), etc.) wiring. Here, the power supply wiring is connected to the metal layer 112', and the cathode 116 of the organic light emitting diode can receive power through the connection between the source / drain metal 108' and the metal layer 112'. The metal layer 112' can be in contact with the power supply wiring and can extend along the outermost sidewall of the planarization layer 109 to contact the cathode 116 on the top of the planarization layer 109. The metal layer 112' can be a metal layer formed of the same material and in the same process as the anode 112 of the organic light emitting diode.

[0052] FIG. 4 is a diagram illustrating a sub-pixel of an organic light emitting display device according to an embodiment of the present disclosure.

[0053] In an organic light emitting display device, the cathode may be oxidized due to oxygen and / or moisture entering from the outside, and the light efficiency may be reduced due to diffuse reflection caused by external light.

[0054] To prepare for this phenomenon, the OLED display according to the embodiment of the present specification further includes a capping layer on the cathode 116. The capping layers 117 and 118 may be formed of an organic film and / or an inorganic film. FIG. 4 shows an example in which the capping layer is embodied as an organic film 117 on the cathode 116 and an inorganic film 118 on the organic thin film. The organic film 117 may be formed of an organic material having a large refractive index. Also, the inorganic film 118 may have a different refractive index from the organic film 117.

[0055] However, the inventors have found weaknesses that appear even in the light-emitting layer structure shown in Fig. 4. One of them is that even if a cover layer with the structure shown in Fig. 4 is provided, as the size of the display device increases, a color shift occurs depending on the viewing angle. As a result, the difference in color feeling depending on the viewing angle may become significant in the display device. In particular, in the case of a display device that is long from side to side, such as a display device for a vehicle, it has been confirmed that the difference in image quality recognized by the driver is also large because the difference in viewing angle between the side close to the driver's seat and the side far from the driver's seat is large.

[0056] The inventors of the present invention have recognized the above-mentioned weaknesses and have devised a structure that can effectively reduce the change in image quality due to the viewing angle.

[0057] FIG. 5 is a diagram illustrating a sub-pixel of an organic light emitting display device according to another embodiment of the present disclosure.

[0058] Among the components in FIG. 5, the same components as those in FIGS. 1 to 4 will not be described again. The organic light emitting display device according to this embodiment may include a structure for suppressing color shift due to viewing angle. The color shift suppression structure may be provided by optimizing the shape and arrangement of a capping layer that covers the upper part of the organic light emitting element. The capping layer is provided to adjust optical characteristics, and may include a first cover layer 517 on the upper part of the organic light emitting element, and second cover layers 518_R, 518_G, and 518_B on the first cover layer 517.

[0059] The organic light emitting display device according to this embodiment may include an organic light emitting device provided in each of a plurality of sub-pixels (R, G, B), and a color shift suppression structure on the organic light emitting device. Each of the sub-pixels (R, G, B) further includes a driving circuit, wiring, electrodes, etc. in addition to the anode 112, light emitting part 114, and cathode 116 of the organic light emitting device.

[0060] The color shift prevention structure can protect the organic light emitting device and improve light extraction efficiency. In addition, the color shift prevention structure can reduce a decrease in color depending on a viewing angle. The color shift prevention structure includes a first cover layer 517 on the organic light emitting device and second cover layers 518_R, 518_G, and 518_B on the first cover layer, and the second cover layers 518_R, 518_G, and 518_B can be provided differently for each of the sub-pixels (R, G, and B).

[0061] The first cover layer 517 may be an organic film made of an organic oxide (e.g., SiO2). The first cover layer 517 may be in contact with and directly cover the upper portion of the cathode 116 of the organic light emitting element. The first cover layer 517 may have a uniform thickness overall, or may have different thicknesses for each of the sub-pixels (R, G, B).

[0062] The second cover layer 518 may be an inorganic film made of lithium fluoride (LiF) or the like. The second cover layer 518 may have a circular, elliptical, or polygonal shape, and may have the same shape as the anode 112 of the organic light emitting device. When the second cover layer 518 is disposed on the first cover layer 517, light emitting efficiency and color purity may be increased due to a microcavity effect.

[0063] The degree of refraction of light emitted from a corresponding sub-pixel can be adjusted depending on the area of ​​the second cover layer 518. That is, the larger the area of ​​the second cover layer 518, the more light is refracted, and relatively more light is perceived in the direction of a larger viewing angle (viewing angle of 0 degrees when viewed from the front of the display device). In addition, the degree of refraction by the second cover layer varies depending on the wavelength of light, and light with a relatively longer wavelength is refracted more. As a result, light with a relatively shorter wavelength shows a large decrease in brightness and / or color at points where the viewing angle is large.

[0064] Considering the principle as described above, the second cover layers 518_R, 518_G, and 518_B are configured to harmonize the cognitive changes by hue at points with a large viewing angle (the left and right sides of the display device). Therefore, the second cover layers 518_R, 518_G, and 518_B can have a wider area as the wavelength of the light emitted from the corresponding sub-pixels (R, G, B) is shorter. For example, the area of the second cover layer 518_B corresponding to the sub-pixel (B) that emits blue light is wider than the area of the second cover layer 518_G corresponding to the sub-pixel (G) that emits green light, and the area of the second cover layer 518_G corresponding to the sub-pixel (G) that emits green light can be wider than the area of the second cover layer 518_R corresponding to the sub-pixel (R) that emits red light. That is, the area of the second cover layer can become wider in the order of R < G < B sub-pixels. Through such a configuration, at the viewing angle of the side where more refracted light (RF_R, RF_G, RF_B) is recognized, the luminance reduction rate is similar for each sub-pixel, and as a result, the difference in color perception at the pixel can be alleviated.

[0065] The form of the second cover layer can be provided in more variety. When the second cover layer 518 has the same shape as the anode 112 of the organic light-emitting element, the second cover layer 518 can be provided to have an area smaller than that of the anode 112 (for example, 50% to 90%). The anode 112 can have different shapes and sizes for each sub-pixel, and the same applies to the second cover layer. Furthermore, the area of the second cover layer 518_B corresponding to the sub-pixel (B) that emits blue light can be 90% of the anode 112_B, the area of the second cover layer 518_G corresponding to the sub-pixel (G) that emits green light can be 70% of the anode 112_G, and the area of the second cover layer 518_R corresponding to the sub-pixel (R) that emits red light can be embodied in a way such as 50% of the anode 112_R.

[0066] Meanwhile, the second cover layers 518_R, 518_G, and 518_B may be formed in a hemispherical shape to function like a lens. Also, the interface where the first cover layer 517 and the second cover layers 518_R, 518_G, and 518_B come into contact may be formed unevenly instead of flat to increase the amount of light refracted. Here, the interface may have a roughness of a predetermined value or more.

[0067] The second cover layers 518_R, 518_G, 518_B may be applied differently to different regions of the display device. For example, the display device may have a first region including a first ratio of sub-pixels with the second cover layer on top, and a second region including a second ratio of sub-pixels with the second cover layer on top, where the second ratio may be greater than the first ratio. For example, the first region may have the second cover layer on only ½ of the sub-pixels, and the second region may have the second cover layer on all of the sub-pixels.

[0068] The first region may be closer to a user, and the second region may be farther from the user. That is, a second viewing angle (θ2) at which the user views the second region may be larger than a first viewing angle (θ1) at which the user views the first region (θ1<θ2). Through this structure, the display device according to the embodiment of the present specification may provide more uniform perceived image quality depending on the viewing angle.

[0069] The above-mentioned structure can suppress the degradation of the perceived image quality due to the usage environment, especially the viewing angle. This can improve the usability of the organic light-emitting display device. Such an advantage is very useful for a display device for a vehicle, which has a long left-right length.

[0070] Although the embodiments of the present specification have been described in detail above with reference to the accompanying drawings, the present specification is not necessarily limited to these embodiments, and various modifications can be made within the scope of the technical idea of ​​the present specification. Therefore, the embodiments disclosed in the present specification are for the purpose of explanation, not for the purpose of limiting the technical idea of ​​the present invention, and the scope of the technical idea of ​​the present invention is not limited by such embodiments. The respective features of some embodiments of the present invention can be partially or fully combined or combined with each other, and can be technically linked and driven in various ways by those skilled in the art, and each embodiment can be implemented independently of each other or together in a related relationship.

[0071] The scope of protection of the present invention should be interpreted according to the following claims, and all technical ideas within the scope equivalent thereto should be interpreted as being included in the scope of the present invention.

Claims

1. A display panel including a plurality of sub-pixels; An organic light-emitting element provided in each of the plurality of sub-pixels; and A color shift suppressing structure for suppressing a color shift depending on a viewing angle is provided on the upper portion of the organic light emitting device, the color shift suppression structure includes a first cover layer on the organic light emitting device and a plurality of second cover layers on the first cover layer, the second cover layers are provided differently for each of the sub-pixels, one of the plurality of second cover layers has a larger area as the wavelength of light emitted from the corresponding sub-pixel becomes shorter; the first cover layer is an organic film; the second cover layers are inorganic films; An organic light-emitting display device, wherein the refraction of light emitted from the corresponding sub-pixel is adjusted depending on the area of ​​the second cover layer.

2. The organic light emitting display device of claim 1 , wherein the first cover layer is in contact with an upper portion of the cathode of the organic light emitting element.

3. The organic light emitting display device of claim 2 , wherein the first cover layer directly covers an upper portion of the cathode of the organic light emitting device.

4. The organic light emitting display device according to claim 1 , wherein the plurality of second cover layers have the same shape as the anodes of the organic light emitting devices.

5. The organic light emitting display device of claim 4 , wherein the area of ​​the second cover layer is 50% to 90% of the area of ​​the anode of the organic light emitting element.

6. an area of ​​the second cover layer corresponding to the sub-pixel emitting blue light is larger than an area of ​​the second cover layer corresponding to the sub-pixel emitting green light; The organic light-emitting display device according to claim 4 , wherein an area of ​​the second cover layer corresponding to the sub-pixel emitting green light is larger than an area of ​​the second cover layer corresponding to the sub-pixel emitting red light.

7. The organic light emitting display device of claim 1 , wherein the second cover layers are hemispherical in shape.

8. The organic light-emitting display device according to claim 1 , wherein an interface between the first cover layer and the second cover layers has a roughness equal to or greater than a predetermined value.

9. a first region including at least one subpixel having the plurality of second cover layers thereon in a first ratio, and a second region including at least one subpixel having the plurality of second cover layers thereon in a second ratio; The organic light emitting display device of claim 1 , wherein the second ratio is different from the first ratio.

10. The organic light emitting display device of claim 9 , wherein the second ratio is greater than the first ratio.

11. The organic light emitting display device of claim 9 , wherein a second viewing angle at which a user views the second region is greater than a first viewing angle at which a user views the first region.

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