Display device

Abstract

An embodiment of the present disclosure relates to a display device including: a substrate on which a plurality of sub-pixels are disposed, each of the plurality of sub-pixels including a first light emitting area and a second light emitting area surrounding the first light emitting area; a first planarization layer on the substrate; a second planarization layer disposed on the first planarization layer and open in a region overlapping the first light emitting region, and including a first portion inclined and overlapping the second light emitting region and a second portion surrounding the first portion; a bank layer on the second planarization layer and open in the first light emitting region; and a lens on the bank layer and disposed to at least partially overlap a region including the first portion. According to an embodiment of the present disclosure, it is possible to minimize a decrease in brightness of the display device while providing a function of limiting a viewing angle.

Description

[0001] Cross - reference to related applications

[0002] This application claims priority to Korean Patent Application No. 10 - 2023 - 0197485, filed on December 29, 2023, which is incorporated herein by reference in its entirety for all purposes as if fully set forth herein. Technical field

[0003] The present disclosure relates to a display device, and more particularly, to a display device capable of improving light extraction efficiency. Background art

[0004] An emissive display device is a self - emissive display device, and different from a liquid crystal display device (LCD), an emissive display does not require a separate light source and can be manufactured in a thin and light form. In addition, an emissive display device is advantageous in terms of power consumption due to low - voltage operation, and has excellent color reproduction, response speed, viewing angle, and contrast ratio (CR), and is being studied as a next - generation display device.

[0005] Emissive display devices may be used in various places. Therefore, a user may selectively limit the viewing angle to prevent the display screen from being exposed to people around, and various techniques are being used to limit the viewing angle.

[0006] Since some of the light emitted from the light - emitting layer may be absorbed inside the emissive display device, there may be problems of reduced brightness and reduced light extraction efficiency of the display device. Therefore, the inventors of the present disclosure have proposed a display device capable of preventing a reduction in brightness of the emissive display device and improving light extraction efficiency while limiting the viewing angle. Summary of the invention

[0007] Embodiments of the present disclosure may provide a display device capable of minimizing a reduction in brightness of the display device caused by light emitted from the light - emitting layer being trapped inside the display device.

[0008] Embodiments of the present disclosure may provide a display device capable of improving the light extraction efficiency of the display device.

[0009] The problems to be solved according to embodiments of the present disclosure are not limited to the above problems, and those skilled in the art can clearly understand another problem from the following description.

[0010] According to an embodiment of the present disclosure, a display device can be provided that can prevent brightness reduction. A first planarization layer can be formed on a substrate. A second planarization layer can be formed on the first planarization layer. The second planarization layer can include at least one opening region and can include at least a part having an inclined surface around the opening region. A bank layer can be formed on the second planarization layer. A lens can be formed on the bank layer. The lens can be disposed to at least partially overlap with a region including a part having an inclined surface.

[0011] The display device according to an embodiment of the present disclosure can have an effect of minimizing a reduction in the brightness of the display device.

[0012] In addition, it can have an effect of improving light extraction efficiency.

[0013] In addition, according to an embodiment of the present disclosure, a display device can be provided that can reduce power consumption by improving light extraction efficiency.

[0014] The effects of the present disclosure are not limited to the above effects, and other effects not described will be clearly understood by those skilled in the art from the following description. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] Figure 1 An example of the structure of a display device according to an embodiment of the present disclosure and a circuit structure included in a sub-pixel is shown.

[0016] Figure 2A And Figure 2B is a diagram showing an example of a planar structure of a display device according to an embodiment of the present disclosure.

[0017] Figure 3 Shows Figure 2A an example of a cross-sectional structure of a part I-I' shown in.

[0018] Figure 4 Is Figure 3 an enlarged view of part A of.

[0019] Figure 5A And Figure 5B is a diagram showing another example of a planar structure of a display device according to an embodiment of the present disclosure.

[0020] Figure 6 Shows Figure 5A an example of a cross-sectional structure of a part II-II' shown in.

[0021] Figure 7 Is Figure 6 an enlarged view of part B of.

[0022] Figure 8 This is a diagram for explaining the optical characteristics of a display device according to an embodiment of the present disclosure.

[0023] Fig. 9 An example of the light-emitting device structure of a display device according to an embodiment of the present disclosure is shown. Detailed Embodiments

[0024] With reference to the accompanying drawings and the detailed description of the embodiments, the advantages and features of the present disclosure and the methods for achieving them will become apparent. The present disclosure should not be construed as being limited to the embodiments set forth below and can be implemented in various different forms. On the contrary, these embodiments are provided so that the present disclosure will be thorough and complete and will fully convey the scope of the present disclosure to those of ordinary skill in the art.

[0025] The shapes, sizes, ratios, angles, quantities, etc. depicted in the drawings used to illustrate the embodiments are merely illustrative, and the present disclosure is not limited to the embodiments shown in the drawings. Throughout this document, the same reference numerals and symbols will be used to refer to the same or similar components. In the following description of the present disclosure, a detailed description of known functions and components incorporated into the present disclosure will be omitted when it is determined that the description may make the subject matter in some embodiments of the present disclosure quite unclear. It should be understood that, unless explicitly described to the contrary, the terms "comprising," "including," "having," and any variations thereof used herein are intended to cover non-exclusive inclusion. Unless explicitly described to the contrary, the description of components in the singular form herein is intended to include the description of components in the plural form.

[0026] In the analysis of components, it should be understood that even if not explicitly described, an error range is still included therein.

[0027] When spatial relative terms such as "on," "above," "under," "below," and "on the side" are used herein to describe the relationship between one element or component and another element or component, there may be one or more intermediate elements or components between one element or component and other elements or components, unless terms such as "immediately" or "directly" are used.

[0028] In addition, terms such as "first" and "second" may be used herein to describe various components. However, it should be understood that these components are not limited by these terms. These terms are only used to distinguish one element or component from other elements or components. Therefore, within the spirit of the present disclosure, the first component hereinafter referred to as the first may be the second component.

[0029] The features of the exemplary embodiments of the present disclosure may be partially or completely coupled or combined with each other, and may work together with each other or may be operated in various technical ways. In addition, each exemplary embodiment may be executed independently, or may be associated with other embodiments and executed in cooperation with other embodiments.

[0030] Hereinafter, various embodiments will be described in detail with reference to the accompanying drawings.

[0031] Figure 1 An example of the structure of a display device according to an embodiment of the present disclosure and a circuit structure included in a sub-pixel is shown.

[0032] Referring to Figure 1 , a plurality of sub-pixels SP may be disposed in a display area of a display panel 110 included in the display device 100.

[0033] Each of the plurality of sub-pixels SP may include a light-emitting device ED and a sub-pixel circuit unit configured to drive the light-emitting device ED.

[0034] The sub-pixel circuit unit may include a driving transistor T1 for driving the light-emitting device ED, a scanning transistor T2 for transmitting a data voltage VDATA to a first node N1 of the driving transistor T1, and a storage capacitor Cst for maintaining a constant voltage during one frame.

[0035] The driving transistor T1 may include a first node N1 to which a data voltage is applied, a second node N2 electrically connected to the light-emitting device ED, and a third node N3 to which a driving voltage VDD is applied from a driving voltage line DVL. In the driving transistor T1, the first node N1 may be a gate node, the second node N2 may be a source node or a drain node, and the third node N3 may be a drain node or a source node. Hereinafter, for convenience of explanation, as an example, a case where the first node N1 in the driving transistor T1 is a gate node, the second node N2 is a source node, and the third node N3 is a drain node is shown.

[0036] The light-emitting device ED may include a first electrode 201, a light-emitting layer 202, and a second electrode 203. The first electrode 201 may be a pixel electrode provided in each sub-pixel SP, and may be electrically connected to the second node N2 of the driving transistor T1 of each sub-pixel SP. The second electrode 203 may be a common electrode commonly provided in a plurality of sub-pixels SP, and a base voltage (VSS) may be applied thereto.

[0037] Alternatively, the first electrode 201 may be a common electrode, and the second electrode 203 may be a pixel electrode. Hereinafter, for convenience of explanation, it is assumed that the first electrode 201 is a pixel electrode and the second electrode 203 is a common electrode.

[0038] The light-emitting device ED may have a specific light-emitting region, and the number of light-emitting regions may be one or more, as will be described later.

[0039] The light-emitting device ED may be an organic light-emitting diode (OLED), an inorganic light-emitting diode, or a quantum dot light-emitting device. In the case where the light-emitting device ED is an organic light-emitting diode, the light-emitting layer 202 in the light-emitting device ED may include an organic light-emitting layer containing an organic material. For example, the light-emitting layer 202 may include a tandem structure having two or more stacked units, but the embodiments of the present disclosure are not limited thereto.

[0040] The scan transistor T2 may be controlled to be turned on and off by a scan signal SCAN, which is a gate signal applied through a gate line GL, and the scan transistor T2 may be electrically connected between a first node N1 of the driving transistor T1 and a data line DL.

[0041] The storage capacitor Cst may be electrically connected between a first node N1 and a second node N2 of the driving transistor T1.

[0042] The sub-pixel circuit unit may have a 2T1C structure including two transistors DT and ST and one capacitor Cst, and in some cases, may further include one or more transistors. Alternatively, the sub-pixel circuit unit may further include one or more capacitors.

[0043] The storage capacitor Cst may be an external capacitor intentionally designed outside the driving transistor T1, rather than a parasitic capacitor (e.g., Cgs, Cgd) of an internal capacitor existing between the first node N1 of the driving transistor T1 and the second node (N2). Each of the driving transistor T1 and the scan transistor T2 may be an n-type transistor or a p-type transistor.

[0044] Circuit elements within each sub-pixel, particularly the light-emitting device ED implemented using an organic light-emitting diode OLED containing an organic material, may be vulnerable to external moisture or oxygen. Therefore, a encapsulation layer 210 may be provided on the display panel 110 to prevent oxygen from permeating into the circuit elements (particularly the light-emitting device ED). The encapsulation layer 210 may be provided to cover the light-emitting device ED.

[0045] A layer providing a touch function and a separate layer providing a viewing angle adjustment function may be additionally provided on the encapsulation layer 210.

[0046] The layer providing the touch function may include layers such as a touch buffer layer, a touch interlayer insulating layer, and touch electrodes. The layer providing the viewing angle adjustment function may include a lens, a viewing angle blocking layer, etc. The layers for the touch function and the layers for the viewing angle adjustment function will be described in detail below.

[0047] Figure 2A and Figure 2B is a diagram showing an example of a planar structure of a display device according to an embodiment of the present disclosure.

[0048] Referring to Figure 2A and Figure 2B In the active area (A / A) of the display device 100, a plurality of sub-pixels SP may be provided.

[0049] Each of the plurality of sub-pixels SP may include at least one light-emitting area EA.

[0050] The light-emitting area EA may be defined as an area where a first electrode 201, a light-emitting layer 202, and a second electrode 203 are sequentially stacked. For example, the first electrode 201 may be an anode electrode. For example, the second electrode 203 may be a cathode electrode.

[0051] Each light-emitting area EA of the sub-pixel SP may be surrounded by a non-light-emitting area NEA. That is, the area other than the light-emitting area EA may be the non-light-emitting area NEA. In addition, the non-light-emitting area NEA of one sub-pixel SP may be connected to the non-light-emitting area NEA of another sub-pixel SP.

[0052] A blocking layer 221 or a metal layer 223 may be provided on the non-light-emitting area NEA, as will be described later. The metal layer 223 may include touch electrodes.

[0053] A lens 300 may be provided on the area overlapping with the light-emitting area EA.

[0054] The lens 300 may be arranged in a plan view to cover the light-emitting area EA of each sub-pixel SP. The horizontal width of the lens 300 may be greater than the width of the light-emitting area EA. However, the present disclosure is not limited thereto, and at least a part of the horizontal width of the lens 300 may be equal to the width of the light-emitting area EA.

[0055] As Figure 2A and Figure 2B shown, the lens 300 may be arranged to correspond to one sub-pixel SP and cover the light-emitting area EA included in one sub-pixel SP. However, it is not necessarily limited thereto, and the lens 300 may be arranged to correspond to a plurality of sub-pixels SP and cover all the light-emitting areas EA included in the corresponding light-emitting areas EA of the plurality of sub-pixels SP.

[0056] The lens 300 can be used to change the path of light from the light-emitting region EA.

[0057] Depending on its three-dimensional shape, the lens 300 can be used to change the path of light in all directions in the light from the light-emitting region EA, or the lens 300 can be used to change only the path of light in a specific direction.

[0058] In the case where the lens 300 is used to change the path of light in all directions in the light from the light-emitting region EA, the lens 300 can have Figure 2A the shape shown.

[0059] Referring to Figure 2A the lens 300 can have a circular cross-sectional area on a plane, or can have a hemispherical shape with a raised upper surface in a direction perpendicular to the Figure 2A plane shown.

[0060] If the lens 300 has an upwardly convex hemispherical shape or a half-sphere shape in the region overlapping with the light-emitting region EA, that is, if the vertical height of the lens 300 increases towards the center of the light-emitting region EA, the light emitted from the light-emitting region EA can be refracted on the upper surface of the lens 300 and bent towards the center of the light-emitting region EA.

[0061] That is, Figure 2A the lens 300 shown can be used to collect light from the light-emitting region EA in all directions in a narrow range within the viewing angle.

[0062] If the lens 300 is used to change the path of light in a specific direction in the light from the light-emitting region EA, the lens 300 can have Figure 2B the shape shown.

[0063] Referring to Figure 2B the lens 300 can have a rectangular cross-sectional area in a plan view, and can have a half-cylinder shape or a semi-cylindrical shape with a partially raised upper surface in a direction perpendicular to the Figure 2B plane shown. That is, when the lens 300 is cut in a direction perpendicular to the Figure 2B plane shown, the cross-section can be a semi-circle with a constant area.

[0064] If the lens 300 has a semi-cylindrical shape in the region overlapping with the light-emitting region EA, light from the light-emitting region EA in a specific direction can be refracted on the upper surface of the lens 300 and guided to the center of the light-emitting region EA. For example, among the light from the light-emitting region EA, the light traveling in a direction parallel to the top surface or the bottom surface of the semi-cylinder can be refracted at the upper surface of the lens 300 and guided to the center of the light-emitting region EA.

[0065] That is, Figure 2B The lens 300 shown can be used to collect light from the light-emitting region EA in a specific direction within a narrow range in the viewing angle. However, among the light from the light-emitting region EA, the light in a direction other than the specific direction for collecting light may not be collected within the narrow range in the viewing angle.

[0066] As described above, the direction or degree of viewing angle limitation can be changed according to the shape of the lens 300. Therefore, a switchable privacy mode can be achieved by changing the shape of the lens 300 for each region where the sub-pixels SP are placed.

[0067] For example, in a region where little privacy protection is required, a semi-cylindrical lens as shown in Figure 2B can be used in each sub-pixel SP to limit the viewing angle only in the up and down directions and not in the left and right directions, thereby ensuring a wide viewing angle.

[0068] On the other hand, in a region where high privacy protection is required, a hemispherical lens or a half-spherical lens as shown in Figure 2A can be placed in each sub-pixel SP to limit the viewing angle in all directions of up, down, left, and right, thereby selectively ensuring a narrow viewing angle.

[0069] That is, although not shown in detail in Figure 2A or Figure 2B , the display device 100 can selectively achieve a wide viewing angle or a narrow viewing angle by differentiating between the region with the semi-cylindrical lens and the region with the hemispherical lens and driving each sub-pixel SP at different times.

[0070] Meanwhile, among the light emitted from the light-emitting device ED, the light that does not reach the lens 300 can be absorbed by the blocking layer 221 described later, or reflected by the metal layer 223 described later. That is, by enabling the light that cannot be guided to the lens 300 to be absorbed inside the display device 100, the above-described viewing angle limitation technique can be effectively achieved.

[0071] Hereinafter, a cross-sectional structure of a display device 100 including a lens 300, a blocking layer 221, and a metal layer 223 will be described.

[0072] Figure 3 An example of a cross-sectional structure of a portion I-I' shown is Figure 2A shown.

[0073] Referring to Figure 3 , the display device 100 may include a substrate 120.

[0074] The substrate 120 may include a first substrate 121 and a second substrate 122, and may include an intermediate film 123 between the first substrate 121 and the second substrate 122. Here, for example, the intermediate film 123 may be an inorganic film and may be used to block moisture penetration.

[0075] A first buffer layer 130 may be provided on the substrate 120.

[0076] The first buffer layer 130 may be a single layer or multiple layers. If the first buffer layer 130 is multiple layers, the first buffer layer 130 may include a multi-buffer layer 131 and an active buffer layer 132.

[0077] A first light-blocking layer 140 may be provided between the first buffer layer 130 and the substrate 120. The first light-blocking layer 140 may overlap all or part of the first active layer 150.

[0078] The first light-blocking layer 140 may be used as a light-shielding portion for blocking light from the bottom.

[0079] Various transistors T1 and T2, a storage capacitor 180, and various electrodes or signal lines may be formed on the first buffer layer 130.

[0080] A first transistor T1 may be provided on the first buffer layer 130. The first transistor T1 may include a first active layer 150, a first source electrode 151, a first drain electrode 152, and a first gate electrode 153.

[0081] A first gate insulating layer 154 may be provided on the first active layer 150 of the first transistor T1.

[0082] Here, the first active layer 150 of the first transistor T1 may include a first channel region overlapping the first gate electrode 153, a first source connection region on one side of the first channel region, and a first drain connection region on the other side of the first channel region.

[0083] A first interlayer insulating layer 155 may be provided on the first gate insulating layer 154.

[0084] A second buffer layer 160 and a second gate insulating layer 170 may be provided on the first interlayer insulating layer 155. A second light blocking layer 156 may be provided between the first interlayer insulating layer 155 and the second buffer layer 160. The second light blocking layer 156 may have the same function as the first light blocking layer 140.

[0085] A second transistor T2 may be provided on the second buffer layer 160. The second transistor T2 may be a transistor for transmitting various signals or voltages to various electrodes inside the display panel.

[0086] A second interlayer insulating layer 171 may be provided on the second transistor T2.

[0087] A first source electrode 151 and a first drain electrode 152 of the first transistor T1 may be provided on the second interlayer insulating layer 171.

[0088] The first source electrode 151 and the first drain electrode 152 of the first transistor T1 may be connected to the first source connection region and the first drain connection region of the first active layer 150 through vias in the second interlayer insulating layer 171, the second gate insulating layer 170, the second buffer layer 160, the first interlayer insulating layer 155, and the first gate insulating layer 154, respectively.

[0089] The storage capacitor 180 may include a first capacitor electrode 181 and a second capacitor electrode 182. The first interlayer insulating layer 155 may be provided between the first capacitor electrode 181 and the second capacitor electrode 182.

[0090] A third interlayer insulating layer 190 may be provided on the first transistor T1. That is, the third interlayer insulating layer 190 may be provided on the first source electrode 151 and the first drain electrode 152 of the first transistor T1.

[0091] A connection electrode 191 may be provided on the third interlayer insulating layer 190.

[0092] The connection electrode 191 may be an electrode capable of transferring the electrical connection between the first source electrode 151 of the first transistor T1 and the first electrode 201 of the light emitting device ED.

[0093] The connection electrode 191 may be electrically connected to the first source electrode 151 of the first transistor T1 through a hole in the third interlayer insulating layer 190.

[0094] A first planarization layer 192 may be provided on the connection electrode 191 and the third interlayer insulating layer 190.

[0095] Although Figure 3The structure in which the first planarization layer 192 is disposed on the third interlayer insulating layer 190 is shown, but embodiments of the present disclosure are not limited thereto. For example, the first planarization layer 192 may be disposed on the third interlayer insulating layer 190, and another planarization layer may be additionally disposed on the first planarization layer 192.

[0096] The first electrode 201 of the light-emitting device ED may be disposed on the first planarization layer 192.

[0097] The first electrode 201 may be made of an opaque conductive material for reflecting light. For example, the opaque conductive material may include at least one of metals such as aluminum (Al), gold (Au), silver (Ag), copper (Cu), tungsten (W), molybdenum (Mo), chromium (Cr), tantalum (Ta), and titanium (Ti), or an alloy thereof, but is not limited thereto.

[0098] Figure 3 The first electrode 201 having a single-layer structure is shown, but is not necessarily limited thereto.

[0099] The bank layer 204 may be disposed on the first electrode 201 and the first planarization layer 192.

[0100] The bank layer 204 may include bank holes exposing a part of the upper surface of the first electrode 201. That is, the bank holes formed in the bank layer 204 may overlap a part of the first electrode 201.

[0101] The light-emitting layer 202 may be disposed on the bank holes exposing a part of the upper surface of the first electrode 201. That is, the light-emitting layer 202 may be disposed on the first electrode 201 that does not overlap with the bank layer 204.

[0102] The second electrode 203 may be disposed on the light-emitting layer 202 and the bank layer 204.

[0103] The second electrode 203 may be made of a transparent conductive material.

[0104] At least one spacer 205 may exist between the second electrode 203 and the bank layer 204. At least one spacer 205 may be arranged to overlap the contact hole region. The contact hole region formed in the first planarization layer 192 may be filled with the bank layer 204, and the spacer 205 may be formed on the upper part of the contact hole region, so that the height of the bank layer 204 in the contact hole region including the spacer 205 may be greater than the height of the bank layer 204 overlapping the opening region part.

[0105] The spacer 205 may be formed of the same material as the bank layer 204, but is not limited thereto. The bank layer 204 and the spacer 205 may be formed of a transparent insulating material.

[0106] A encapsulation layer 210 can be provided on the second electrode 203.

[0107] The encapsulation layer 210 can include a first encapsulation layer 211, a second encapsulation layer 212 on the first encapsulation layer 211, and a third encapsulation layer 213 on the second encapsulation layer 212.

[0108] The first encapsulation layer 211 and the third encapsulation layer 213 can be made of at least one inorganic material selected from silicon nitride (SiNx), silicon oxide (SiOx), or aluminum oxide (AlyOz), but are not limited thereto. The first encapsulation layer 211 and the third encapsulation layer 213 can be formed using a vacuum deposition method such as chemical vapor deposition (CVD) or atomic layer deposition (ALD), but are not limited thereto.

[0109] The second encapsulation layer 212 can cover foreign substances or particles that may appear during the manufacturing process. In addition, the second encapsulation layer 212 can planarize the surface of the first encapsulation layer 211.

[0110] A layer for providing a touch function can be provided on the encapsulation layer 210.

[0111] The layer for providing a touch function can include a touch buffer layer 220, a touch interlayer insulating layer 222, a metal layer 223, and a touch planarization layer 224. As described above, the metal layer 223 can include touch electrodes.

[0112] Specifically, the touch buffer layer 220 can be provided on the third encapsulation layer 213. The touch buffer layer 220 can block external moisture from penetrating into the light-emitting device ED containing organic materials.

[0113] A barrier layer 221 and a touch interlayer insulating layer 222 can be provided on the touch buffer layer 220.

[0114] The barrier layer 221 can be made of at least one of a black pigment, a black resin, graphite, black ink, gravure ink, black spray, and black enamel. If the barrier layer 221 is made of the above materials, the barrier layer can absorb at least 80% of visible light.

[0115] The barrier layer 221 can be arranged to be spaced apart. The area where the barrier layer 221 is spaced apart can correspond to the light-emitting area EA. That is, the separation distance between the barrier layers 221 can be equal to the width of the light-emitting area EA, but is not limited thereto, and can be greater than the width of the light-emitting area EA.

[0116] The barrier layer 221 can not overlap with the light-emitting area EA. That is, the barrier layer 221 can be provided on the non-light-emitting area NEA. The barrier layer 221 can be arranged in a plan view to cover the entire non-light-emitting area NEA, or can be arranged to cover a part of the non-light-emitting area NEA.

[0117] Alternatively, the barrier layer 221 may have an area overlapping with a part of the light-emitting region EA. In this case, the barrier layer 221 may be arranged to cover the entire non-light-emitting region NEA and may cover a part of the light-emitting region EA. In addition, the width of the area where the barrier layer 221 is open may be smaller than the width of the light-emitting region EA.

[0118] A metal layer 223 may be provided on the touch interlayer insulating layer 222. The metal layers 223 may be arranged to be spaced apart. For example, the metal layer 223 may be on the same layer as the touch electrode and made of the same material as the touch electrode.

[0119] The separation distance between the metal layers 223 may be the same as the separation distance between the barrier layers 221. That is, the separation distance between the metal layers 223 may be equal to or smaller than the width of the light-emitting region EA.

[0120] The metal layer 223 may not overlap with the light-emitting region EA. That is, like the barrier layer 221, the metal layer 223 may be provided on the non-light-emitting region NEA. The metal layer 223 may be provided in a region including the entire non-light-emitting region NEA in a plan view, or may be provided only on a part of the non-light-emitting region NEA.

[0121] Alternatively, the metal layer 223 may have an area overlapping with a part of the light-emitting region EA. In this case, the metal layer 223 may be provided in a region including the entire non-light-emitting region NEA. In addition, the separation distance between the metal layers 223 may be smaller than the width of the light-emitting region EA.

[0122] The metal layer 223 may send a touch detection signal to a touch driving circuit (not shown) or receive a touch driving signal from the touch driving circuit.

[0123] A lens 300 and a touch planarization layer 224 may be provided on the metal layer 223.

[0124] As described above, the lens 300 may have a convex upper surface in a direction perpendicular to the substrate 120.

[0125] The lens 300 may be provided in a region overlapping with the light-emitting region EA. The maximum horizontal width of the lens 300 may be greater than the light-emitting region EA. However, it is not limited thereto, and the maximum horizontal width of the lens 300 may be equal to the width of the light-emitting region EA.

[0126] However, preferably, the maximum horizontal width of the lens 300 is not less than the width of the light-emitting region EA. In the case where the maximum horizontal width of the lens 300 is less than the width of the light-emitting region EA, the lens 300 and the metal layer 223 may be spaced apart. A touch planarization layer 224 may be provided in the region where the lens 300 and the metal layer 223 are spaced apart.

[0127] In this case, a part of the light emitted from the light-emitting layer 202 may travel to the separation space between the lens 300 and the metal layer 223, that is, the region where the touch planarization layer 224 is provided. The light traveling to the region where the touch planarization layer 224 is provided may not pass through the interface between the touch interlayer insulating layer 222 and the touch planarization layer 224, and may be totally reflected at the interface.

[0128] For example, if the maximum width of the lens 300 in the horizontal direction is less than the width of the light-emitting region EA, some of the emitted light does not enter the inside of the lens 300, and this light may be totally reflected inside the display device 100 and may not be emitted to the outside of the display device 100. Therefore, the maximum horizontal width of the lens 300 may be greater than or equal to the width of the light-emitting region EA.

[0129] The touch planarization layer 224 may be provided to cover the metal layer 223 and the lens 300, and may be formed of the same material as the second encapsulation layer 212, but is not limited thereto.

[0130] Hereinafter, the cross-sectional structure of the display device 100 including the lens 300, the barrier layer 221, and the metal layer 223 will be described in detail.

[0131] Figure 4 is Figure 3 an enlarged view of part A of.

[0132] Referring to Figure 4 In the case of the top-emission type display device 100, the light emitted from the light-emitting region EA of the sub-pixel SP may travel toward the top of the display device 100.

[0133] A part of the light traveling toward the top of the display device 100 may be absorbed or reflected inside the display device 100 and may be trapped inside the display device 100 instead of traveling to the outside. Alternatively, a part of the light may be refracted and guided in a specific direction. Therefore, the user of the display device 100 may recognize only a part of the light emitted from the display device 100.

[0134] Specifically, if the angle θ between the light emitted from the light-emitting layer 202 and the vertical direction perpendicular to the substrate 120 is greater than θ1, the light emitted from the light-emitting layer can travel toward the blocking layer 221, such that most of the light can be absorbed into the blocking layer 221. That is, among the light emitted from the light-emitting layer, the light with an angle θ formed with the vertical direction of the substrate 120 being θ1 or greater may not be emitted to the outside of the display device 100.

[0135] If the angle θ between the light emitted from the light-emitting layer 202 and the vertical direction of the substrate 120 is greater than θ2 and less than θ1, the light emitted from the light-emitting layer can be reflected on the metal layer 223. The light reflected by the metal layer 223 can travel toward the blocking layer 221 again and can be absorbed by the blocking layer 221. That is, among the light emitted from the light-emitting layer, the light with an angle θ with respect to the vertical direction of the substrate 120 being greater than or equal to θ2 and less than θ1 may not be emitted to the outside of the display device 100.

[0136] If the angle θ between the light emitted from the light-emitting layer and the vertical direction of the substrate 120 is less than θ2, the light emitted from the light-emitting layer can travel toward the inside of the lens 300 without being absorbed by the blocking layer 221 or without being absorbed again in the blocking layer 221 after being reflected from the metal layer 223. The light traveling inside the lens 300 can be refracted at the upper surface of the lens 300 and emitted to the outside of the display device 100.

[0137] In this case, due to the refractive index difference between the lens 300 and the touch planarization layer 224 surrounding the lens, the path of the light passing through the upper surface of the lens 300 can be changed to point to the axis of symmetry of the lens 300. Here, the axis of symmetry of the lens 300 may be a vertical axis formed at the portion of the lens having the maximum vertical width.

[0138] That is, as described above, the light emitted from the light-emitting layer 202 can be absorbed by the internal components of the display device 100, can be reflected back inside, or can be refracted at the interface of specific components, thereby changing the path of the light. Therefore, among the light emitted from the light-emitting layer 202, only the light with an angle θ with respect to the vertical direction of the substrate 120 being less than θ2 can be emitted to the outside of the display device 100.

[0139] Therefore, only when the user views the display device 100 from a position offset by an angle less than θ2 from the forward direction with respect to the display device 100, the light emitted from the light-emitting layer 202 can be visible.

[0140] In addition, even when the angle θ between the light emitted from the light-emitting layer 202 and the vertical direction of the substrate 120 is less than θ2, as described above, due to the refraction on the upper surface of the lens 300, the path of the emitted light may also be changed to point to the axis of symmetry of the lens 300. Therefore, the user of the display device 100 can recognize the light emitted from the light-emitting layer 202 only when the viewing angle of the display device 100 is small.

[0141] Therefore, the viewing angle of the display device 100 can be restricted. That is, if the display device 100 includes the blocking layer 221, the metal layer 223, and the lens 300, the light emitted from the light-emitting layer 202 can be emitted to the outside of the display device 100 only through a limited area within the viewing angle range of the display device 100. Therefore, the area where the user of the display device 100 can recognize the image provided through the display screen can be restricted.

[0142] Therefore, the display device 100 can effectively provide a privacy protection function by including not only the lens 300 but also the blocking layer 221 and the metal layer 223.

[0143] In addition, the viewing angle range where the light emitted from the light-emitting layer 202 can be emitted to the outside can be changed by adjusting the arrangement structure and the spacing of the internal components (i.e., the blocking layer 221, the metal layer 223, and the lens 300) included in the display device 100. Therefore, the degree of viewing angle restriction can be adjusted by adjusting the structure or the spacing of the internal components according to the usage situation. That is, the degree of privacy protection can be adjusted according to the situation.

[0144] Meanwhile, in the case where the display device 100 includes the blocking layer 221 and the metal layer 223, as Figure 4 shown, some of the light emitted from the light-emitting layer 202 can be absorbed by the blocking layer 221 inside the display device 100, or can be reflected from the metal layer 223 and absorbed by the blocking layer 221 again. Therefore, the brightness of the display device 100 may be reduced within the viewing angle range. In addition, the light extraction efficiency of the display device 100 may be correspondingly reduced.

[0145] For example, in the case of providing the blocking layer 221 and the metal layer 223, an improved viewing angle restriction function can be provided, but at the same time, the brightness of the display device 100 may be reduced, and the light extraction efficiency may be reduced.

[0146] Hereinafter, a solution to this problem will be described with reference to the drawings.

[0147] Figure 5A and Figure 5B are diagrams showing another example of the planar structure of a display device according to an embodiment of the present disclosure. Figure 6 Shows Figure 5A An example of the cross-sectional structure of part II-II'. Figure 7 is Figure 6 an enlarged view of part B of

[0148] Figure 5A 、 Figure 5B and Figure 6 The planar structure and cross-sectional structure of the display device 100 shown can be the same as those of the display device 100 described with reference to Figure 2A 、 Figure 2B and Figure 3 , except that the display device 100 further includes a second planarization layer 193 and the structure of the first electrode 201 is changed. Therefore, redundant descriptions can be omitted.

[0149] Referring to Figure 5A 、 Figure 5B and Figure 6 , each of the plurality of sub-pixels SP provided in the active area A / A of the display device 100 may include a first light-emitting area EA1 and a second light-emitting area EA2.

[0150] The first light-emitting area EA1 may be defined as an area where the first electrode 201, the light-emitting layer 202, and the second electrode 203 are sequentially stacked.

[0151] The second light-emitting area EA2 may be an area formed by light emitted from the light-emitting layer 202 and reflected by the first electrode 201.

[0152] The first light-emitting area EA1 may be surrounded by a first non-light-emitting area NEA1. The first non-light-emitting area NEA1 may be an area that is black when the display panel is in the on state. Alternatively, due to light incident from at least one of the first light-emitting area EA1 and the second light-emitting area EA2, the first non-light-emitting area NEA1 may be an area with a lower brightness than the first light-emitting area EA1 and the second light-emitting area EA2.

[0153] The first non-light-emitting area NEA1 may be surrounded by the second light-emitting area EA2.

[0154] The second light-emitting area EA2 may be surrounded by a second non-light-emitting area NEA2.

[0155] The second non-light-emitting area NEA2 of one sub-pixel SP may be connected to the second non-light-emitting area NEA2 of another sub-pixel SP. That is, the second non-light-emitting area NEA2 may refer to the area between the second light-emitting area EA2 of one sub-pixel SP and the second light-emitting area EA2 of another sub-pixel SP.

[0156] A lens 300 may be provided in a region overlapping with the first light-emitting region EA1 and the second light-emitting region EA2.

[0157] In a plan view, the lens 300 may be arranged to cover the first light-emitting region EA1 and the second light-emitting region EA2 of each sub-pixel SP.

[0158] As Figure 5A or Figure 5B shown, in a plan view, the lens 300 may be arranged to cover all of the first light-emitting region EA1, the first non-light-emitting region NEA1, and the second light-emitting region EA2 of each sub-pixel SP.

[0159] For example, the lens 300 may at least partially overlap with the first light-emitting region EA1, the first non-light-emitting region NEA1, and the second light-emitting region EA2 of each sub-pixel SP.

[0160] That is, the horizontal width of the lens 300 may be greater than the sum of the widths of the first light-emitting region EA1, the first non-light-emitting region NEA1, and the second light-emitting region EA2. However, it is not limited thereto, and at least a part of the horizontal width of the lens 300 may be equal to the sum of the widths of the first light-emitting region EA1, the first non-light-emitting region NEA1, and the second light-emitting region EA2.

[0161] As Figure 5A and Figure 5B shown, the lens 300 may be arranged to correspond to one sub-pixel SP and cover the first light-emitting region EA1 and the second light-emitting region EA2 included in one sub-pixel SP. However, it is not necessarily limited thereto, and the lens 300 may be arranged to correspond to a plurality of sub-pixels SP and cover each of the first light-emitting region EA1 and the second light-emitting region EA2 included in the plurality of sub-pixels SP.

[0162] As described above, in the case where the lens 300 is used to change the paths of light in all directions in the light from the first light-emitting region EA1 and the second light-emitting region EA2, the lens 300 may have Figure 5A the shape shown.

[0163] Referring to Figure 5A , in a plan view, the lens 300 may have a hemispherical shape or a hemispherical surface with a circular cross-sectional area, and have a convex upper surface in a direction perpendicular to Figure 5A the plane shown.

[0164] If the lens 300 has an upwardly convex hemispherical shape in the region overlapping with the light-emitting region EA, that is, if the vertical height of the lens 300 increases toward the center of the first light-emitting region EA1, the light emitted from the first light-emitting region EA1 and the second light-emitting region EA2 can be refracted on the upper surface of the lens 300 and guided to the center of the first light-emitting region EA1.

[0165] That is to say, Figure 5A the illustrated lens 300 can be used to collect the light from the first light-emitting region EA1 and the second light-emitting region EA2 in all directions within a narrow range in the viewing angle.

[0166] Alternatively, if the lens 300 is used to change the path of the light in a specific direction among the light from the first light-emitting region EA1 and the second light-emitting region EA2, the lens 300 can have a shape as Figure 5B illustrated.

[0167] Referring to Figure 5B , the lens 300 can have a semi-cylindrical shape with a rectangular cross-sectional area in a plane and have a partially convex upper surface in a direction perpendicular to Figure 5B the illustrated plane. Here, when the lens 300 is cut in a direction perpendicular to Figure 5B the illustrated plane, the cross-section can be a semi-circle with a constant area.

[0168] If the lens 300 has a semi-cylindrical shape in the region overlapping with the first light-emitting region EA1 and the second light-emitting region EA2, the light emitted from the first light-emitting region EA1 and the second light-emitting region EA2 in a specific direction can be refracted on the upper surface of the lens 300 and guided to the center of the first light-emitting region EA1. For example, among the light from the first light-emitting region EA1, the light traveling in a direction parallel to the upper surface or the lower surface of the semi-cylinder can be refracted at the upper surface of the lens 300 and bent toward the center of the first light-emitting region EA.

[0169] That is to say, Figure 5B the illustrated lens 300 can be used to collect the light in a specific direction among the light emitted from the first light-emitting region EA1 and the second light-emitting region EA2 within a narrow range in the viewing angle. However, among the light emitted from the first light-emitting region EA1 and the second light-emitting region EA2, the light in a direction other than the specific direction of collecting light may not be collected within a narrow range in the viewing angle.

[0170] Meanwhile, since the lens 300 is arranged to cover not only the first light-emitting region EA1 but also the second light-emitting region EA2, the maximum width of the lens 300 in the horizontal direction can be equal to or greater than the sum of the widths of the first light-emitting region EA1, the first non-light-emitting region NEA1, and the second light-emitting region EA2. Accordingly, the display device 100 can prevent a reduction in brightness while providing a viewing angle limiting function.

[0171] Hereinafter, a cross-sectional structure of the display device 100 including the lens 300, the blocking layer 221, and the metal layer 223 will be described.

[0172] Referring to Figure 6 and Figure 7 , a second planarization layer 193 may be provided on the first planarization layer 192.

[0173] The second planarization layer 193 may include at least one opening region.

[0174] The opening region of the second planarization layer 193 may partially overlap with the first light-emitting region EA1.

[0175] The second planarization layer 193 may be made of the same material as the first planarization layer 192, but is not limited thereto.

[0176] The horizontal width of the region where the second planarization layer 193 is open (i.e., the opening region) may be greater than the horizontal width of the first light-emitting region EA1.

[0177] The second planarization layer 193 may include a first portion 193a and a second portion 193b surrounding the first portion 193a.

[0178] The first portion 193a may mean a portion where the second planarization layer 193 has an inclined side surface. That is, the first portion 193a may refer to a portion where the vertical height of the second planarization layer 193 is not constant.

[0179] The second portion 193b is a portion that does not include the first portion 193a and may mean a portion surrounding the first portion 193a and having a constant vertical height.

[0180] The region where the second planarization layer 193 is open (i.e., the opening region) may mean a space between the first portions 193a of the second planarization layer 193.

[0181] Referring to Figure 6 and Figure 7 , the lens 300 may overlap with the first portion 193a of the second planarization layer 193. However, the present disclosure is not limited thereto, and the lens 300 may overlap with the first portion 193a of the second planarization layer 193 and may also overlap with a part of the second portion 193b.

[0182] The first electrode 201 may be provided in at least some regions on the first planarization layer 192 and the second planarization layer 193.

[0183] The first electrode 201 may be provided within the opening region of the second planarization layer 193. Specifically, the first electrode 201 may be provided on the bottom surface and the side surface of the opening region provided in the second planarization layer 193, and may be provided to extend to a part of the upper surface of the second planarization layer 193. The first electrode 201 may be in contact with the upper surface of the first planarization layer 192 in a region corresponding to the opening region of the second planarization layer 193.

[0184] In addition, the first electrode 201 may be in contact with the connection electrode 191 provided below the first planarization layer 192 through contact holes provided in the second planarization layer 193 and the first planarization layer 192.

[0185] The first electrode 201 may include an inclined portion 201a.

[0186] The inclined portion 201a may be a part of the first electrode 201, which is provided on the inclined side surface of the second planarization layer 193, that is, on the inclined surface of the first portion 193a of the second planarization layer 193. The inclined portion 201a may be provided on each inclined surface of the first portion 193a on both sides of the opening region of the second planarization layer 193.

[0187] The inclined portion 201a may have the same inclination angle as the first portion 193a of the second planarization layer 193.

[0188] As described above, some of the light emitted from the light-emitting layer 202 may be reflected from the inclined portion 201a to form a second light-emitting region EA2. Therefore, the region where the inclined portion 201a is provided may mean the second light-emitting region EA2.

[0189] As described above, the horizontal width of the lens 300 may be equal to or greater than the sum of the widths of the first light-emitting region EA1, the first non-light-emitting region NEA1, and the second light-emitting region EA2. Here, since the region where the inclined portion 201a is provided may mean the second light-emitting region EA2, the maximum horizontal distance d between the inclined portions 201a provided on each inclined surface of the first portion 193a on both sides of the opening region of the second planarization layer 193 max may be equal to the sum of the widths of the first light-emitting region EA1, the first non-light-emitting region NEA1, and the second light-emitting region EA2.

[0190] Here, the maximum horizontal distance d between the inclined portions 201a maxIt may mean the maximum value among the horizontal distances from an arbitrary point on the inclined portion 201a on one side to an arbitrary point on the inclined portion 201a provided on the other side.

[0191] Meanwhile, since the display device 100 further includes the inclined portion 201a, the display device 100 can have the function of preventing brightness reduction and increasing light extraction efficiency while providing a limited viewing angle. Hereinafter, this will be described with reference to the accompanying drawings.

[0192] Referring to Figure 7 , the barrier layer 221 and the metal layer 223 may be located outside the outer boundary of the second light-emitting region EA2.

[0193] The separation distance between the barrier layers 221 may be equal to or greater than the sum of the widths of the first light-emitting region EA1, the first non-light-emitting region NEA1, and the second light-emitting region EA2.

[0194] The separation distance between the metal layers 223 may be equal to or greater than the sum of the widths of the first light-emitting region EA1, the first non-light-emitting region NEA1, and the second light-emitting region EA2.

[0195] As described above, among the light emitted from the light-emitting layer 202, the light traveling outside the outer boundary of the second light-emitting region EA2 - that is, the light with an angle θ with respect to the vertical direction of the substrate 120 greater than a specific value - can be absorbed by the barrier layer 221 as described above, or can be reflected from the metal layer 223 and then absorbed again into the barrier layer 221. Therefore, this light cannot be emitted to the outside of the display device 100.

[0196] However, if the display device 100 includes the inclined portion 201a, a part of the light emitted from the light-emitting layer 202 and traveling toward the barrier layer 221 can change its path.

[0197] For example, if the display device 100 does not include the inclined portion 201a, among the light emitted from the light-emitting layer 202, some of the light with an angle θ with respect to the vertical direction of the substrate 120 being θ1 or greater can travel toward the barrier layer 221. The light guided to the barrier layer 221 can be absorbed by the barrier layer 221 and thus cannot be emitted to the outside.

[0198] Referring to Figure 7 , according to an embodiment of the present disclosure, if the display device 100 includes the inclined portion 201a, some of the light with an angle θ with respect to the vertical direction of the substrate 120 being θ1 or greater can be reflected from the inclined portion 201a when traveling toward the barrier layer 221, so that it is no longer absorbed by the barrier layer 221 and can be emitted to the outside of the display device 100.

[0199] That is, if the display device 100 includes the inclined portion 201a, a larger amount of light can be emitted to the outside of the display device 100 compared to the case where there is no inclined portion 201a.

[0200] In addition, referring to Figure 6 and Figure 7 , the lens 300 can overlap with the inclined portion 201a or the first portion 193a of the second planarization layer 193.

[0201] If the lens 300 is disposed to overlap with the inclined portion 201a or the first portion 193a of the second planarization layer 193, then as Figure 7 shown, some of the light emitted from the second light-emitting region EA2 can travel inside the lens 300, and can be refracted at the upper surface of the lens 300 and bent toward the center of the lens 300.

[0202] That is, not only the light emitted from the first light-emitting region EA1 but also the light emitted from the second light-emitting region EA2 can travel toward the inside of the lens 300.

[0203] In summary, the display device 100 including the inclined portion 201a, the lens 300, the blocking layer 221, and the metal layer 223 can absorb or refract a part of the light emitted from the light-emitting layer 202, thereby providing a viewing angle limiting function. In addition, in the case where the display device 100 includes the inclined portion 201a, more light can be emitted to the outside, thereby preventing a decrease in brightness within the viewing angle while providing the viewing angle limiting function.

[0204] In addition, if the display device 100 includes the inclined portion 201a, then in addition to the light emitted from the first light-emitting region EA1, the light emitted through the second light-emitting region EA2 can also be emitted to the outside of the display device 100. Therefore, the light extraction efficiency of the display device 100 can be improved.

[0205] Figure 8 is a diagram for explaining the optical characteristics of a display device according to an embodiment of the present disclosure.

[0206] Figure 8 Shows that the display device 100 (embodiment) having the second light-emitting region EA2 generated by the second planarization layer 193 and the display device 100 (comparative example) not having the second light-emitting region EA2 generated by the second planarization layer 193 have different light extraction efficiencies and brightnesses within the viewing angle.

[0207] Regarding the light extraction efficiency, the display device 100 having the second light-emitting region EA2 has a value of 135% or more (≥135%), which is higher than 130% of the display device 100 not having the second light-emitting region EA2.

[0208] Regarding the luminance ratio, Figure 8 the angle value θ in the table of Figure 8 may mean the angle θ formed by the light from the light-emitting layer 202 and the vertical direction of the substrate 120.

[0209] The angle θ formed by the light emitted from the light-emitting layer 202 and the vertical direction of the substrate 120 may refer to the angle formed based on the front direction of the display device. That is, the angle may mean the degree to which the user's viewing direction of the display screen deviates from the front of the display screen. For example, when the user views the display screen from the front, the angle θ between the light from the light-emitting layer and the vertical direction of the substrate 120 may be 0 degrees. Alternatively, if the user views the display screen from the side of the display screen, the angle θ formed by the light from the light-emitting layer and the vertical direction of the substrate 120 may be 90 degrees.

[0210] The luminance ratio may refer to the ratio of the luminance at an angle offset by a specific angle (i.e., a specific angle θ formed by the light from the light-emitting layer 202 and the vertical direction of the substrate 120) with respect to the front of the display screen to the luminance at the front of the display screen.

[0211] In the region where the angle θ between the light from the light-emitting layer 202 and the vertical direction of the substrate 120 is ±40, the luminance ratio of the display device in the embodiment is 42.5%, which indicates an increase in luminance compared to 37% in the comparative example.

[0212] In the region where the angle θ between the light from the light-emitting layer 202 and the vertical direction of the substrate 120 is ±50, the luminance ratio of the display device in the embodiment is 29%, which indicates an increase in luminance compared to 26% in the comparative example.

[0213] That is, if the display device 100 includes the second light-emitting region EA2, the light extraction efficiency of the display device 100 can be increased, and the luminance in a specific region within the viewing angle of the display device 100 can be increased.

[0214] Fig. 9 An example of the light-emitting device structure of a display device according to an embodiment of the present disclosure is shown.

[0215] Referring to Fig. 9 , the display device may include a light-emitting device ED.

[0216] The light-emitting device ED may include: a first electrode 201 formed on a substrate defining a red sub-pixel region Rp, a green sub-pixel region Gp, and a blue sub-pixel region Bp; a first organic light-emitting layer composed of a hole injection layer (820; HIL), a first hole transport layer (830; first HTL), a first hole control layer (835; first HCL), a first red light-emitting layer (840; first red EML), a first green light-emitting layer (841; first green EML), and a first blue light-emitting layer (842; first blue EML); a second organic light-emitting layer composed of a first electron transport layer (850; first ETL), a first charge generation layer (860; N-CGL), a second charge generation layer (865; P-CGL), a second hole transport layer (870; second HTL), a second hole control layer (875; second HCL), a second red light-emitting layer (880; second red EML), a second green light-emitting layer (881; second green EML), and a second blue light-emitting layer (882; second blue EML); a second electron transport layer (890; second ETL); a second electrode 203; and a cover layer (910, CPL).

[0217] In addition, the light-emitting device ED according to an embodiment of the present disclosure may be an organic light-emitting device having a double-stack structure, in which a first light-emitting unit (1100) including the first organic light-emitting layer and a second light-emitting unit (1200) including the second organic light-emitting layer are stacked between the first electrode 201 and the second electrode 203.

[0218] For example, in the light-emitting device ED according to an embodiment of the present disclosure, the first light-emitting unit or the first light-emitting part 1100 may include a first organic light-emitting layer composed of a hole injection layer 820, a first hole transport layer 830, a first hole control layer 835, a first red light-emitting layer 840, a first green light-emitting layer 841, a first blue light-emitting layer 842, and a first electron transport layer 850.

[0219] In the light-emitting device ED according to an embodiment of the present disclosure, the second light-emitting unit or the second light-emitting part 1200 may include a second organic light-emitting layer composed of a second hole transport layer 870, a second hole control layer 875, a second red light-emitting layer 880, a second green light-emitting layer 881, a second blue light-emitting layer 882, and a second electron transport layer 890.

[0220] The light-emitting device according to an embodiment of the present disclosure may include a first charge generation layer 860 as an n-type charge generation layer and a second charge generation layer 865 as a p-type charge generation layer between the first light-emitting unit 1100 and the second light-emitting unit 1200.

[0221] In a display device including an organic light emitting device according to an embodiment of the present disclosure, gate lines and data lines that cross each other to define each pixel region may be disposed on a substrate, and power lines extending parallel to any one of the gate lines and the data lines may be disposed in each pixel region. In addition, in each pixel region, a switching thin film transistor connected to the gate line and the data line and a driving thin film transistor connected to the switching thin film transistor may be provided. The driving thin film transistor may be connected to the first electrode 201.

[0222] The first electrode 201 may be located on the substrate to correspond to each of a red sub-pixel region (Rp), a green sub-pixel region (Gp), and a blue sub-pixel region (Bp), and may be made of a reflective electrode.

[0223] The hole injection layer 820 may be positioned on the first electrode 201 to correspond to all sub-pixel regions among the red sub-pixel region (Rp), the green sub-pixel region (Gp), and the blue sub-pixel region (Bp).

[0224] The hole injection layer 820 may facilitate hole injection and may include at least one of the following: HATCN (1,4,5,8,9,11-hexaazatriphenylene-hexacarbonitrile), CuPc (copper phthalocyanine), PEDOT (poly(3,4)-ethylenedioxythiophene), PANI (polyaniline), and NDP (N,N-dinaphthyl-N,N'-diphenylbenzidine), but is not limited thereto.

[0225] The first hole transport layer 830 and the second hole transport layer 870 may be formed to correspond to all pixel regions among the red sub-pixel region (Rp), the green sub-pixel region (Gp), and the blue sub-pixel region (Bp). The first hole transport layer 830 may be located on the hole injection layer 820, and the second hole transport layer 870 may be located on the second charge generation layer 865.

[0226] The first hole transport layer 830 and the second hole transport layer 870 may facilitate hole transport and may include at least one of the following: NPD (N,N-dinaphthyl-N,N'-diphenylbenzidine), TPD (N,N'-bis-(3-methylphenyl)-N,N'-bis-(phenyl)-benzidine), s-TAD, and MTDATA (4,4',4”-tris(N-3-methylphenyl-N-phenyl-amino)-triphenylamine), but is not limited thereto.

[0227] In a light emitting device ED according to an embodiment of the present disclosure, the first hole control layer 835 may be positioned on the first hole transport layer 830 to correspond to all sub-pixel regions among the red sub-pixel region (Rp), the green sub-pixel region (Gp), and the blue sub-pixel region (Bp).

[0228] The second hole control layer 875 may be located on the second hole transport layer 870 to correspond to all sub-pixel regions in the red sub-pixel region (Rp), the green sub-pixel region (Gp), and the blue sub-pixel region (Bp).

[0229] Since holes have a higher mobility characteristic than electrons at high temperatures, the first hole control layer 835 and the second hole control layer 875 can prevent the following phenomenon: holes pass through the first organic light-emitting layer including the first red light-emitting layer 840, the first green light-emitting layer 841, and the first blue light-emitting layer 842, which is the region where electrons and holes recombine to emit light, and the second organic light-emitting layer including the second red light-emitting layer 880, the second green light-emitting layer 881, and the second blue light-emitting layer 882, and move to the first electron transport layer 850 and the second electron transport layer 890, thus leaving the light-emitting region. The first hole control layer 835 and the second hole control layer 875 can be made of materials such as carbazole derivatives, triarylamine derivatives, or triamine derivatives. For example, the first hole control layer 835 and the second hole control layer 875 can be made of TPD (N,N'-bis-(3-methylphenyl)-N,N'-bis(phenyl)-benzidine), α-NPB (bis[N-(1-naphthyl)-N-phenyl]benzidine), TDAPB (1,3,5-tris[4-(diphenylaminophenyl)benzene), TCTA (tris(4-carbony-9-yl)triphenylamine), spiro-TAD (2,2',7,7'-tetra(N,N-diphenylamino)-9,9'-spirobifluorene), CBP (4,4'-bis(carbazol-9-yl)biphenyl), BFA-1T (4-[bis(9,9-dimethylfluoren-2-yl)amino]phenyl), spiroTCBz (triclabendazole), and TBA, but are not limited thereto.

[0230] The first hole control layer 835 and the second hole control layer 875 can be made of the same material among the above materials. Alternatively, considering the hole mobility characteristics in the first light-emitting unit 1100 and the second light-emitting unit 1200, the first hole control layer 835 and the second hole control layer 875 can be made of different materials among the above materials.

[0231] The first red light-emitting layer 840 may be located in the red sub-pixel region (Rp) on the first hole transport layer 830, and the second red light-emitting layer 880 may be located in the red sub-pixel region (Rp) on the second hole transport layer 870. The first red light-emitting layer 840 and the second red light-emitting layer 880 may each include a light-emitting material that emits red light, and the light-emitting material may be formed using a phosphorescent material or a fluorescent material.

[0232] For example, the first red light-emitting layer 840 and the second red light-emitting layer 880 may include a host material including CBP (4,4'-bis(carbazol-9-yl)biphenyl) or mCP (1,3-bis(N-carbazolyl)benzene), or the first red light-emitting layer 840 and the second red light-emitting layer 880 may be made of a phosphorescent material including a dopant, and the dopant includes one or more of the following: PQIr(acac) (bis(1-phenylquinoline)acetylacetonatoiridium), PQIr(tris(1-phenylquinoline)iridium), and PtOEP (octaethylporphyrin platinum). Alternatively, the first red light-emitting layer 840 and the second red light-emitting layer 880 may be made of a fluorescent material including PBD:Eu(DBM)3(phenanthroline) or perylene, but is not limited thereto.

[0233] The first green light-emitting layer 841 may be located in the green sub-pixel region (Gp) on the first hole transport layer 830, and the second green light-emitting layer 881 may be located in the green sub-pixel region (Gp) on the second hole transport layer 870. The first green light-emitting layer 841 and the second green light-emitting layer 881 may each include a light-emitting material that emits green light, and the light-emitting material may be formed using a phosphorescent material or a fluorescent material.

[0234] For example, the first green light-emitting layer 841 and the second green light-emitting layer 881 may include a host material including CBP or mCP, or may be made of a phosphorescent material including a dopant material, such as an iridium complex including Ir(ppy)3 (fac-tris(2-phenylpyridine)iridium). Alternatively, the first green light-emitting layer 841 and the second green light-emitting layer 881 may be made of a fluorescent material including Alq3 (tris(8-hydroxyquinoline)aluminum), but is not limited thereto.

[0235] The first blue light-emitting layer 842 may be located in the blue sub-pixel region (Bp) on the first hole transport layer 830, and the second blue light-emitting layer 882 may be located in the blue sub-pixel region (Bp) on the second hole transport layer 870. The first blue light-emitting layer 842 and the second blue light-emitting layer 882 may each include a light-emitting material that emits blue light, and the light-emitting material may be formed using a phosphorescent material or a fluorescent material.

[0236] For example, the first blue light-emitting layer 842 and the second blue light-emitting layer 882 may include a host material including CBP or mCP, or the first blue light-emitting layer 842 and the second blue light-emitting layer 882 may be made of a phosphorescent material including a dopant material containing (4,6-F2ppy)2Irpic, but are not limited thereto. In addition, the first blue light-emitting layer 842 and the second blue light-emitting layer 882 may be made of a fluorescent substance including any one of the following: spiro-DPVBi, spiro-6P, dialkylbenzene (DSB), stilbene (DSA), PFO-based polymer, and PPV-based polymer, but are not limited thereto.

[0237] The first electron transport layer 850 may be located on the first red light-emitting layer 840, the first green light-emitting layer 841, and the first blue light-emitting layer 842 to correspond to all sub-pixel regions in the red sub-pixel region (Rp), the green sub-pixel region (Gp), and the blue sub-pixel region (Bp). In addition, the second electron transport layer 890 may be located on the second red light-emitting layer 880, the second green light-emitting layer 881, and the second blue light-emitting layer 882 to correspond to all sub-pixel regions in the red sub-pixel region (Rp), the green sub-pixel region (Gp), and the blue sub-pixel region (Bp).

[0238] The first electron transport layer 850 and the second electron transport layer 890 may transport and inject electrons, and the thicknesses of the first electron transport layer 850 and the second electron transport layer 890 may be adjusted in consideration of electron transport characteristics.

[0239] The first electron transport layer 850 and the second electron transport layer 890 may facilitate the transport of electrons, and may be made of at least one of the following: Alq3 (aluminum tris(8-hydroxyquinoline)), PBD (2-(4-biphenylyl)-5-(4-tert-butylphenyl)-1,3,4-oxadiazole), TAZ, spiro-PBD, BAlq, and SAlq, but are not limited thereto.

[0240] An electron injection layer (EIL) may be separately and additionally disposed on the second electron transport layer 890.

[0241] The electron injection layer (EIL) may use Alq3 (aluminum tris(8-hydroxyquinoline)), PBD (2-(4-biphenylyl)-5-(4-tert-butylphenyl)-1,3,4-oxadiazole), TAZ, spiro-PBD, BAlq, or SAlq, but are not limited thereto.

[0242] Here, according to an embodiment of the present disclosure, the structure is not limited, and at least one of the hole injection layer 820, the first hole transport layer 830, the second hole transport layer 870, the first electron transport layer 850, the second electron transport layer 890, and the electron injection layer (EIL) may be omitted. In addition, at least one of the first hole transport layer 830, the second hole transport layer 870, the first electron transport layer 850, the second electron transport layer 890, and the electron injection layer (EIL) may be formed of two or more layers.

[0243] The first charge generation layer 860 may be located on the first electron transport layer 850 corresponding to all sub-pixel regions among the red sub-pixel region (Rp), the green sub-pixel region (Gp), and the blue sub-pixel region (Bp), and the second charge generation layer 865 may be located on the first charge generation layer 860 corresponding to all sub-pixel regions among the red sub-pixel region (Rp), the green sub-pixel region (Gp), and the blue sub-pixel region (Bp). The first charge generation layer 860 and the second charge generation layer 865 may have an NP junction structure.

[0244] Referring to Fig. 9 , the first charge generation layer 860 and the second charge generation layer 865 may be located between the first light-emitting unit 1100 and the second light-emitting unit 1200. In addition, the first charge generation layer 860 and the second charge generation layer 865 may adjust the charge balance between the two light-emitting units of the first light-emitting unit 1100 and the second light-emitting unit 1200.

[0245] The first charge generation layer 860 may serve as an n-type charge generation layer (n-CGL) that helps the injection of electrons into the first light-emitting unit 1100 located below the first charge generation layer 860. The second charge generation layer 865 may serve as a p-type charge generation layer (p-CGL) that helps the injection of holes into the second light-emitting unit 1200 located on top of the second charge generation layer 865.

[0246] For example, the first charge generation layer 860, as an n-type charge generation layer (n-CGL) for injecting electrons, may be made of an alkali metal, an alkali metal compound, or an organic material or a composite thereof that acts as an electron injector. In addition, the host material of the first charge generation layer 860 may be made of the same material as the host materials of the first electron transport layer 850 and the second electron transport layer 890. For example, it may be composed of a mixed layer in which an organic material such as an anthracene derivative is doped with a dopant such as lithium (Li), but is not limited thereto.

[0247] The second charge generation layer 865 may be located on the first charge generation layer 860. The second charge generation layer 865 may serve as a p-type charge generation layer (p-CGL) acting as a hole injector, and the host material of the second charge generation layer 865 may be made of the same material as the host materials of the first hole injection layer 820, the first hole transport layer 830, and the second hole transport layer 870. For example, the second charge generation layer 865 may be composed of a mixed layer in which organic materials such as HATCN (1,4,5,8,9,11-hexaazatriphenylene-hexacarbonitrile), CuPc (copper phthalocyanine), and TBAHA (aluminum tris(4-bromophenyl) hexachlorophthalate) are doped with a p-type dopant, but is not limited thereto. In addition, the p-type dopant may be made of F4-TCNQ or NDP-9, but is not limited thereto.

[0248] The second electrode 203 may be located on the second electron transport layer 890 to correspond to all sub-pixel regions in the red sub-pixel region (Rp), the green sub-pixel region (Gp), and the blue sub-pixel region (Bp). For example, the second electrode 203 may be made of an alloy of magnesium and silver (Mg:Ag) and may have transmissive-reflective characteristics. For example, the light emitted from the organic light-emitting layer may be displayed to the outside through the second electrode 203. Since the second electrode 203 has transmissive-reflective characteristics, a part of the light may be guided back to the first electrode 201 again.

[0249] In this way, due to the microcavity effect of repeated reflection occurring between the first electrode 201 acting as a reflective layer and the second electrode 203, light may be repeatedly reflected within the cavity between the first electrode 201 and the second electrode 203, thereby improving the light efficiency.

[0250] In addition, the first electrode 201 serving as a transmissive electrode and the second electrode 203 serving as a reflective electrode may be formed such that the light from the organic light-emitting layer is displayed to the outside through the first electrode 201.

[0251] The cover layer 910 may be located on the second electrode 203. The cover layer 910 may increase the light extraction effect in the organic light-emitting device. The cover layer 910 may be made of one of the following materials: the materials of the first hole transport layer 830, the second hole transport layer 870, the first electron transport layer 850, the second electron transport layer 890, and the host materials of the first red light-emitting layer 840, the second red light-emitting layer 880, the first green light-emitting layer 841, the second green light-emitting layer 881, the first blue light-emitting layer 842, and the second blue light-emitting layer 882, but is not limited thereto. In addition, the cover layer 910 may be omitted.

[0252] Hereinafter, various configurations of a display device capable of preventing brightness reduction while restricting the viewing angle according to embodiments of the present disclosure will be described.

[0253] According to an embodiment of the present disclosure, the display device may further include a first electrode disposed on at least a portion of the first planarization layer and the second planarization layer, and the first electrode may include an inclined portion disposed on a first portion of the second planarization layer.

[0254] According to an embodiment of the present disclosure, the inclined portion may overlap with the second light-emitting region.

[0255] According to an embodiment of the present disclosure, the maximum horizontal distance between the inclined portions may be less than or equal to the maximum width of the lens in the horizontal direction.

[0256] According to an embodiment of the present disclosure, the display device may include a first non-light-emitting region located between the first light-emitting region and the second light-emitting region.

[0257] According to an embodiment of the present disclosure, the first non-light-emitting region may overlap with the lens.

[0258] According to an embodiment of the present disclosure, the display device may further include a barrier layer disposed to be spaced apart under the lens, and the barrier layer is disposed in a region other than the second light-emitting region.

[0259] According to an embodiment of the present disclosure, the separation distance between the barrier layers may be less than or equal to the maximum width of the lens in the horizontal direction.

[0260] According to an embodiment of the present disclosure, the display device may further include a metal layer disposed to be spaced apart between the lens and the barrier layer, and the metal layer is disposed in a region other than the second light-emitting region.

[0261] According to an embodiment of the present disclosure, the separation distance between the metal layers may be less than or equal to the maximum width of the lens in the horizontal direction.

[0262] According to an embodiment of the present disclosure, the display device may further include a first electrode disposed on at least a portion of the first planarization layer and the second planarization layer, and the first electrode may include an inclined portion disposed on an inclined first portion of the second planarization layer.

[0263] According to an embodiment of the present disclosure, the maximum horizontal distance between the inclined portions may be less than or equal to the maximum width of the lens in the horizontal direction.

[0264] According to an embodiment of the present disclosure, the display device may further include a barrier layer disposed to be spaced apart under the lens, and the barrier layer is disposed in a region other than the second light-emitting region.

[0265] According to an embodiment of the present disclosure, the separation distance between the barrier layers may be less than or equal to the maximum width of the lens in the horizontal direction.

[0266] According to an embodiment of the present disclosure, the display device may further include a metal layer disposed to be spaced apart between the lens and the barrier layer, and the metal layer is disposed in an area other than the second light-emitting area.

[0267] According to an embodiment of the present disclosure, the separation distance between the metal layers may be less than or equal to the maximum width of the lens in the horizontal direction.

[0268] According to an embodiment of the present disclosure, the metal layer may be formed of the same material as the touch electrode.

[0269] The above description is presented to enable any person skilled in the art to make and use the inventive concepts of the present disclosure, and the above description is provided in the context of a particular application and its requirements. Various modifications, additions, and substitutions to the described embodiments will be readily apparent to those skilled in the art, and the general principles defined herein can be applied to other embodiments and applications without departing from the spirit and scope of the present disclosure. The above description and the accompanying drawings provide examples of the inventive concepts of the present disclosure for illustrative purposes only. That is, the disclosed embodiments are intended to illustrate the scope of the inventive concepts of the present disclosure. Therefore, the scope of the present disclosure is not limited to the embodiments shown, but should be accorded the broadest scope consistent with the claims.

Claims

1. A display device, comprising: A substrate, on which a plurality of sub-pixels are arranged, each of the plurality of sub-pixels comprising a first light-emitting region and a second light-emitting region surrounding the first light-emitting region; a first planarization layer on the substrate; as well as a second planarization layer, the second planarization layer being disposed on the first planarization layer and opening in a region overlapping the first light emitting region, and the second planarization layer comprising a first portion which is inclined and overlaps the second light emitting region and a second portion surrounding the first portion; a bank layer, the bank layer being located on the second planarization layer and opening in the first light emitting region; as well as A lens is located on the bank layer and is disposed to at least partially overlap with a region including the first portion.

2. The display device according to claim 1, further comprising a first electrode provided on at least a portion of the first planarization layer and the second planarization layer, in, The first electrode includes an inclined portion disposed on the first portion of the second planarization layer.

3. The display device according to claim 2, wherein: The inclined portion overlaps the second light emitting area.

4. The display device according to claim 3, wherein: The maximum horizontal distance between the inclined portions is less than or equal to the maximum width of the lens in the horizontal direction. 5 . The display device according to claim 1 , further comprising a first non-light-emitting area between the first light-emitting area and the second light-emitting area.

6. The display device according to claim 5, wherein: The first non-light emitting area overlaps with the lens. 7 . The display device according to claim 1 , further comprising a barrier layer disposed at intervals below the lens, and the barrier layer is disposed in a region other than the second light emitting region.

8. The display device according to claim 7, wherein: The separation distance between the barrier layers is less than or equal to the maximum width of the lens in the horizontal direction. 9 . The display device according to claim 7 , further comprising a metal layer disposed to be spaced apart between the lens and the barrier layer, and the metal layer is disposed in a region other than the second light emitting region.

10. The display device according to claim 9, wherein: The separation distance between the metal layers is less than or equal to the maximum width of the lens in the horizontal direction.

11. A display device, comprising: a first planarization layer on the substrate; a second planarization layer, the second planarization layer being disposed on the first planarization layer and comprising at least one opening region, and the second planarization layer comprising at least a portion having an inclined surface around the opening region; a bank layer, the bank layer being located on the second planarization layer; as well as A lens is located on the bank layer and is disposed to at least partially overlap a region including the portion having the inclined surface.

12. The display device according to claim 11, further comprising a first electrode disposed on at least a portion of the first planarization layer and the second planarization layer, in, The first electrode includes an inclined portion provided on a portion of the second planarizing layer having the inclined surface.

13. The display device according to claim 12, wherein: The maximum horizontal distance between the inclined portions is less than or equal to the maximum width of the lens in the horizontal direction.

14. The display device according to claim 12, further comprising a barrier layer, the barrier layer being disposed to be spaced apart below the lens and the barrier layer being disposed in a region other than the second light emitting region, in, The second light emitting region is a region formed by light emitted from the light emitting layer located in the opening region and reflected by the first electrode.

15. The display device according to claim 14, further comprising a first light-emitting region, wherein the first light-emitting region is a region where the first electrode and the light-emitting layer are stacked, and a first non-light-emitting region is located between the first light-emitting region and the second light-emitting region, wherein: A separation distance between the barrier layers is equal to or greater than a sum of widths of the first light emitting region, the first non-light emitting region, and the second light emitting region.

16. The display device according to claim 14, wherein: The separation distance between the barrier layers is less than or equal to the maximum width of the lens in the horizontal direction. 17 . The display device according to claim 14 , further comprising a metal layer disposed between the lens and the barrier layer to be spaced apart, and the metal layer is disposed in a region other than the second light emitting region.

18. The display device according to claim 17, wherein: The separation distance between the metal layers is less than or equal to the maximum width of the lens in the horizontal direction.

19. The display device according to claim 17, wherein: The metal layer is formed of the same material as the touch electrode.

20. The display device according to claim 11, wherein: The lens has a hemispherical shape or a hemispherical surface shape having a circular cross-sectional area on a plane, or a semi-cylindrical shape having a rectangular cross-sectional area on a plane.

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