Display divice

Abstract

To provide a display divice that improves a life of a blue color light emission element to improve a color change failure.SOLUTION: A display device 100 contains: a substrate 110 that contains a non-display region having a display region AA in which a plurality of pixels is arranged, a bending region BA that is extended and bent from one side of the display region AA, and a first non-display region NA1 extended from them; a plurality of transistors and a light emission element that are arranged so as to be corresponded to the plurality of pixels on the substrate 110; a sealing part that is arranged onto the plurality of light emission elements, and includes a first inorganic sealing layer 141, an organic sealing layer, and a second inorganic sealing layer; and a data driving part DD that is arranged to the first non-display region NA1, and transmits a signal to the display region. The substrate 110 is bent in the bending region BA, and the first non-display region NA1 is arranged to a lower side of the display region AA. The first inorganic sealing layer 141 can contain a first region 141R1 that is overlapped with the data driving part DD, and a second region 141R2 having a refractive index that is lower than the first region 141R1.SELECTED DRAWING: Figure 2b

Description

[Technical field]

[0001] The present invention relates to a display device, and more particularly, to a display device capable of realizing optimal luminous efficiency while improving the life span of a blue light emitting device. [Background technology]

[0002] As we enter a full-fledged information age, the field of display devices that visually display electrical information signals is rapidly developing, and research is ongoing to develop various display devices with improved performance, such as thinner, lighter, and less power consumption.

[0003] Representative display devices include liquid crystal display devices (LCDs), field emission display devices (FEDs), electro-wetting display devices (EWDs), and organic light emitting display devices (OLEDs).

[0004] Among these, electroluminescence displays, which are displays including organic light emitting displays, are self-emitting displays that do not require a separate light source, unlike liquid crystal displays, and can be manufactured in a lightweight and thin form. In addition, electroluminescence displays are advantageous in terms of power consumption due to low voltage operation, and are also excellent in color realization, response speed, viewing angle, and contrast ratio (CR), and are expected to be used in various fields. Summary of the Invention [Problem to be solved by the invention]

[0005] An object of the present invention is to provide a display device capable of improving color change defects such as pinkish or yellowish by improving the life span of a blue light emitting element.

[0006] Another object of the present invention is to provide a display device capable of minimizing an area where luminous efficiency is reduced, thereby improving the life span of a blue light emitting device and simultaneously realizing optimal luminous efficiency.

[0007] The object of the present invention is not limited to the above-mentioned objects, and other objects not mentioned herein will be clearly understood by those skilled in the art from the following description. [Means for solving the problem]

[0008] A display device according to an embodiment of the present invention includes a display area in which a plurality of pixels are arranged, a substrate including a non-display area having a bending area extending and bending from one side of the display area and a first non-display area extending from the bending area, a plurality of transistors and a plurality of light-emitting elements arranged on the substrate corresponding to each of the plurality of pixels, an encapsulation part arranged on the plurality of light-emitting elements and including a first inorganic encapsulation layer, an organic encapsulation layer and a second inorganic encapsulation layer, and a data driver arranged in the first non-display area and transmitting a signal to the display area, wherein the substrate is bent at the bending area and the first non-display area is arranged below the display area, and the first inorganic encapsulation layer includes a first area overlapping with the data driver and a second area excluding the first area and having a refractive index lower than that of the first area.

[0009] A display device according to another embodiment of the present invention includes a display panel including a display area in which an image is displayed, a non-display area surrounding the display area and a bending area extending from the non-display area, a plurality of light-emitting elements arranged in the display area, a first inorganic encapsulating layer arranged on the plurality of light-emitting elements, an organic encapsulating layer arranged on the first inorganic encapsulating layer, a second inorganic encapsulating layer arranged on the organic encapsulating layer, and a data driver connected to the bending area and arranged on the rear surface of the display panel to transmit a signal to the display panel, wherein the first inorganic encapsulating layer includes a first region arranged corresponding to the data driver and a second region having a lower refractive index than the first region.

[0010] Further details of the embodiments are included in the detailed description and the drawings. Effect of the Invention

[0011] The present invention can increase the refractive index of the first inorganic sealing layer, thereby improving the life span of a blue light emitting element that is vulnerable to high temperature environments.

[0012] The present invention can improve color change defects such as pinkish or yellowish by compensating for the difference in life span between light emitting elements of other hues and blue light emitting elements.

[0013] The present invention can minimize the reduction in luminous efficiency of the light emitting device by limiting the region where the refractive index of the first inorganic sealing layer is increased to the region overlapping with the data driver.

[0014] The effects of the present invention are not limited to the above-mentioned examples, and various other effects are included within the scope of the present invention. [Brief description of the drawings]

[0015] [Figure 1a] 1 is a schematic plan view of a display device according to an embodiment of the present invention; [Figure 1b] FIG. 2 is a plan view of a first inorganic sealing layer of a display device according to an embodiment of the present invention. [Figure 2a] FIG. 1B is a cross-sectional view taken along line II-II' of FIG. [Figure 2b] 4 is a cross-sectional view of a display device according to an embodiment of the present invention when being bent; [Diagram 3] FIG. 2 is a cross-sectional view taken along line III-III' in FIG. [Figure 4] 11 is a graph showing a simulation result of efficiency lifetime of blue light emitting elements of a display device according to an embodiment of the present invention and a display device of a comparative example. [Figure 5a] FIG. 11 is an enlarged plan view of one pixel of a display device according to another embodiment of the present invention. [Figure 5b] FIG. 5b is a cross-sectional view taken along line Vb-Vb' of FIG. 5a. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0016] The advantages and features of the present invention, and the methods for achieving them, will become clear from the detailed description of the embodiments of the present invention, taken in conjunction with the accompanying drawings. However, the present invention is not limited to the embodiments disclosed below, and may be embodied in various different forms. The embodiments are provided solely to ensure that the disclosure of the present invention is complete, and to fully convey the scope of the invention to those skilled in the art to which the present invention pertains. The present invention is defined only by the scope of the claims.

[0017] The shapes, areas, ratios, angles, numbers, etc. disclosed in the drawings for explaining the embodiments of the present invention are illustrative, and the present invention is not limited to the illustrated matters. The same reference symbols refer to the same components throughout the specification. In addition, when describing the present invention, if it is determined that a detailed description of related known technology may unnecessarily obscure the gist of the present invention, the detailed description will be omitted. When "includes," "has," "is made," etc. are used in the present invention, other parts may be added since "only" is not used. When a component is expressed in the singular, it includes the plural unless otherwise explicitly stated.

[0018] When interpreting elements, they are interpreted as including a margin of error even if there is no other explicit description. When describing a positional relationship, for example when describing the positional relationship of two parts using "on top of," "at the top of," "at the bottom of," "next to," etc., since "immediately" or "directly" is not used, one or more other parts may be located between the two parts.

[0019] When an element or layer is referred to as "on" another element or layer, this includes the case where the element or layer is directly on top of the other element, or has other layers or elements interposed therebetween.

[0020] In addition, 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 used merely 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] Like reference numbers refer to like elements throughout the specification.

[0022] The area 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 area and thickness of the components shown.

[0023] The respective features of the various embodiments of the present invention may be partially or fully combined or combined with each other, and may be technically interlocked and driven in various ways, and each embodiment may be implemented independently of each other or may be implemented together in a related relationship.

[0024] In the following, the invention will be described with reference to the drawings.

[0025] 1 is a schematic plan view of a display device according to an embodiment of the present invention, in which only a substrate 110, a pad unit PAD, a data driver DD, and a first inorganic encapsulation layer 141 are shown among various components of a display device 100 for ease of explanation.

[0026] Referring to FIG. 1, a substrate 110 includes a display area AA and a non-display area NA.

[0027] The substrate 110 is a base member for supporting various components of the display device 100, and may be made of an insulating material. For example, the substrate 110 may be made of glass or a plastic material such as polyimide.

[0028] The display area AA is an area for displaying an image, and has a plurality of pixels P arranged therein. A light emitting element for displaying an image and a driver for driving the light emitting element may be arranged in the plurality of pixels P in the display area AA. For example, when the display device 100 is an organic light emitting display device, the light emitting element may be an organic light emitting element including an anode, an organic layer, and a cathode. The driver may include various components such as a power supply line, a gate line, a data line, a transistor, a storage capacitor, etc. for driving the organic light emitting element. In the following, for convenience of explanation, it is assumed that the display device 100 is an organic light emitting display device, but the display device 100 is not limited to an organic light emitting display device.

[0029] Meanwhile, each of the pixels P in the display area AA may include three or more sub-pixels emitting different colors. For example, each of the pixels P may include a red sub-pixel, a green sub-pixel, and a blue sub-pixel. The light emitting elements and transistors arranged in each of the pixels P may be arranged corresponding to the red sub-pixel, the green sub-pixel, and the blue sub-pixel, respectively. However, each of the pixels P may further include a white sub-pixel, and is not limited thereto. Meanwhile, a detailed description of the red sub-pixel, the green sub-pixel, and the blue sub-pixel arranged in the pixels P will be described later with reference to FIGS. 5a and 5b.

[0030] The non-display area NA is an area where no image is displayed, and various wirings and circuits for driving the display elements of the display area AA are arranged in the non-display area NA. For example, the non-display area NA may be arranged with a data driver DD, a gate driver, a link wiring, a pad unit PAD, etc.

[0031] The non-display area NA may be an area extending from the display area AA, but is not limited to this and may be an area surrounding the display area AA.

[0032] The non-display area NA includes a first non-display area NA1, a bending area BA, and a second non-display area NA2. The second non-display area NA2 is an area extending from the display area AA. The bending area BA is an area extending from the second non-display area NA2 and can be bent. The first non-display area NA1 is an area extending from the bending area BA.

[0033] The first non-display area NA1 may include a data driver DD, a pad part PAD, etc. The pad part PAD may include pads connected to various signal lines and a PCB, and may include a power supply pad, a data pad, a gate pad, etc.

[0034] The data driver DD may be mounted or connected to a separate PCB board and connected to the display panel through the pad unit PAD, or may be mounted or connected in a COP (Chip On Panel) form between the pad unit PAD and the display area AA. The data driver DD includes at least one source driver IC (Integrated Circuit). The at least one source driver IC receives digital video data and a source timing control signal from a timing controller. The at least one source driver IC converts the digital video data into a gamma voltage in response to the source timing control signal to generate a data voltage, and supplies the data voltage through the data wiring of the display area AA.

[0035] A plurality of bending patterns are arranged in the bending area BA. The bending area BA is an area that is bent in a final product, and cracks may occur due to stress concentrated on the bending patterns arranged in the bending area BA when the bending area BA is bent. Therefore, the bending pattern may be a pattern of a specific shape in order to minimize cracks. For example, the bending pattern may be a pattern in which conductive patterns having at least one shape of a diamond shape, a rhombus shape, a zigzag shape, and a circle shape are repeatedly arranged. The bending pattern may be any shape other than the above shapes in order to minimize stress concentrated on the bending pattern and cracks, and is not limited thereto.

[0036] The second non-display area NA2 is an area between the bending area BA and the display area AA, where link wiring such as a power link wiring and a data link wiring may be arranged. That is, the second non-display area NA2 serves to transmit signals output from the driving unit to the display area AA. When the substrate 110 includes a release corner area, the second non-display area NA2 may have a shape corresponding to the shapes of the substrate 110 and the display area AA.

[0037] Meanwhile, in FIG. 1a, a first inorganic sealing layer 141 is disposed on a substrate 110, and the first inorganic sealing layer 141 is shown to include a first region 141R1 and a second region 141R2. The first region 141R1 and the second region 141R2 of the first inorganic sealing layer 141 will be described in more detail below with reference to FIGS. 1b to 3.

[0038] Reference is first made to FIGS. 1b to 3 for a more detailed description of the pixels P of the display device 100. FIG.

[0039] FIG 1b is a plan view of a first inorganic encapsulation layer of a display device according to an embodiment of the present invention. FIG 2a is a cross-sectional view taken along IIa-IIa' in FIG 1. FIG 2b is a cross-sectional view of a display device according to an embodiment of the present invention during bending. FIG 3 is a cross-sectional view taken along III-III' in FIG 1. For ease of explanation, FIG 1b shows only a first inorganic encapsulation layer 141 among various components of the display device.

[0040] 2a and 2b, in the display device 100 according to an embodiment of the present invention, the bending region BA is bent so that the data driver DD can be disposed under the display region AA. Specifically, the first non-display region NA1, in which the data driver DD for transmitting a signal to the display region AA is disposed, is bent in the bending region BA so that the first non-display region NA1 and the data driver DD can be disposed under the display region AA.

[0041] At this time, the first region 141R1 of the first inorganic sealing layer 141 is disposed to overlap the data driver DD, which will be described in detail later.

[0042] 3, the display device 100 according to an embodiment of the present invention is a top emission type display device and may include a substrate 110, a buffer layer 111, a transistor 120, a gate insulating layer 112, an interlayer insulating layer 113, a passivation layer 114, a first planarization layer 115, a connecting electrode 190, a second planarization layer 116, a bank 117, a light emitting element 130, and an encapsulation part 140. In this case, the transistor 120 and the light emitting element 130 may be referred to as a display unit DP. That is, the display unit DP may include the transistor 120 and the light emitting element 130.

[0043] The substrate 110 can support various components of the display device 100. The substrate 110 can be made of glass or a plastic material having flexibility. When the substrate 110 is made of a plastic material, it may be made of, for example, polyimide (PI).

[0044] The buffer layer 111 may be disposed on the substrate 110. The buffer layer 111 may be a single layer of silicon nitride (SiNx) or silicon oxide (SiOx) or a multi-layer thereof. The buffer layer 111 may improve adhesion between the substrate 110 and a layer formed on the buffer layer 111, and may serve to block alkaline components that flow out from the substrate 110.

[0045] The transistor 120 may be disposed on the buffer layer 111. The transistor 120 may include an active layer 121, a gate electrode 124, a source electrode 122, and a drain electrode 123. Here, the source electrode 122 may be a drain electrode, and the drain electrode 123 may be a source electrode, depending on the design of the pixel circuit. The active layer 121 of the transistor 120 may be disposed on the buffer layer 111.

[0046] The active layer 121 may be made of various materials such as polysilicon, amorphous silicon, oxide semiconductor, etc. The active layer 121 may include a channel region where a channel is formed when the transistor 120 is operated, and a source region and a drain region on both sides of the channel region. The source region refers to a portion of the active layer 121 connected to the source electrode 122, and the drain region refers to a portion of the active layer 121 connected to the drain electrode 123.

[0047] A gate insulating layer 112 may be disposed on the active layer 121 of the transistor 120. The gate insulating layer 112 may be configured as a single layer of silicon nitride (SiNx) or silicon oxide (SiOx) or a multi-layer thereof. Contact holes may be formed in the gate insulating layer 112 to connect a source electrode 122 and a drain electrode 123 of the transistor 120 to a source region and a drain region of the active layer 121 of the transistor 120, respectively.

[0048] A gate electrode 124 of the transistor 120 may be disposed on the gate insulating layer 112. The gate electrode 124 may be formed of a single layer or multiple layers made of any one of molybdenum (Mo), copper (Cu), titanium (Ti), aluminum (Al), chromium (Cr), gold (Au), nickel (Ni), and neodymium (Nd), or an alloy thereof. The gate electrode 124 may be formed on the gate insulating layer 112 to overlap a channel region of the active layer 121 of the transistor 120.

[0049] An interlayer insulating layer 113 may be disposed on the gate insulating layer 112 and the gate electrode 124. The interlayer insulating layer 113 may be composed of a single layer of silicon nitride (SiNx) or silicon oxide (SiOx) or multiple layers thereof. Contact holes may be formed in the interlayer insulating layer 113 to expose source and drain regions of the active layer 121 of the transistor 120.

[0050] A source electrode 122 and a drain electrode 123 of a transistor 120 may be disposed on the interlayer insulating layer 113 .

[0051] The source electrode 122 and the drain electrode 123 of the transistor 120 may be connected to the active layer 121 of the transistor 120 through contact holes formed in the gate insulating layer 112 and the interlayer insulating layer 113. Thus, the source electrode 122 of the transistor 120 may be connected to the source region of the active layer 121 through contact holes formed in the gate insulating layer 112 and the interlayer insulating layer 113. And, the drain electrode 123 of the transistor 120 may be connected to the drain region of the active layer 121 through contact holes formed in the gate insulating layer 112 and the interlayer insulating layer 113.

[0052] The source electrode 122 and the drain electrode 123 of the transistor 120 may be formed by the same process and may be formed of the same material. The source electrode 122 and the drain electrode 123 of the transistor 120 may be formed as a single layer or multiple layers made of any one of molybdenum (Mo), copper (Cu), titanium (Ti), aluminum (Al), chromium (Cr), gold (Au), nickel (Ni), neodymium (Nd), or an alloy thereof.

[0053] A passivation layer 114 for protecting the source electrode 122 and the drain electrode 123 may be disposed on the source electrode 122 and the drain electrode 123. The passivation layer 114 is an insulating layer for protecting the structure below the passivation layer 114. For example, the passivation layer 114 may be configured as a single layer or multiple layers of silicon oxide (SiOx) or silicon nitride (SiNx), but is not limited thereto. Also, the passivation layer 114 may be omitted depending on the embodiment.

[0054] The first planarization layer 115 may be disposed on the transistor 120 and the passivation layer 114. As shown in FIG. 3, a contact hole for exposing the drain electrode 123 may be formed in the first planarization layer 115. The first planarization layer 115 may be an organic material layer for planarizing the upper part of the transistor 120. For example, the first planarization layer 115 may be formed of an organic material such as an acryl resin, an epoxy resin, a phenolic resin, a polyamide resin, or a polyimide resin. However, without being limited thereto, the first planarization layer 115 may be an inorganic material layer for protecting the transistor 120. For example, the first planarization layer 115 may be formed of an inorganic material such as silicon nitride (SiNx) or silicon oxide (SiOx). The first planarization layer 115 may be configured as a single layer of silicon nitride (SiNx) or silicon oxide (SiOx) or a multilayer thereof.

[0055] The connecting electrode 190 may be disposed on the first planarization layer 115. The connecting electrode 190 may be connected to the drain electrode 123 of the transistor 120 through a contact hole of the first planarization layer 115. The connecting electrode 190 may serve to electrically connect the transistor 120 and the light emitting element 130. For example, the connecting electrode 190 may serve to electrically connect the drain electrode 123 of the transistor 120 and the first electrode 131 of the light emitting element 130. The connecting electrode 190 may be formed as a single layer or multiple layers made of any one of molybdenum (Mo), copper (Cu), titanium (Ti), aluminum (Al), chromium (Cr), gold (Au), nickel (Ni), and neodymium (Nd), or an alloy thereof. The connecting electrode 190 may be formed of the same material as the source electrode 122 and the drain electrode 123 of the transistor 120.

[0056] The second planarization layer 116 may be disposed on the connecting electrode 190 and the first planarization layer 115. As shown in FIG 3, a contact hole for exposing the connecting electrode 190 may be formed in the second planarization layer 116. The second planarization layer 116 may be an organic material layer for planarizing the upper part of the transistor 120. For example, the second planarization layer 116 may be formed of an organic material such as an acryl resin, an epoxy resin, a phenolic resin, a polyamide resin, or a polyimide resin.

[0057] In each of the plurality of pixels P, the light emitting element 130 may be disposed on the second planarization layer 116. The light emitting element 130 may include a first electrode 131 serving as an anode, a light emitting layer 132, and a second electrode 133 serving as a cathode. The first electrode 131 of the light emitting element 130 may be disposed on the second planarization layer 116. The first electrode 131 may be electrically connected to the connecting electrode 190 through a contact hole formed in the second planarization layer 116. Thus, the first electrode 131 of the light emitting element 130 may be electrically connected to the transistor 120 by being connected to the connecting electrode 190 through the contact hole formed in the second planarization layer 116.

[0058] The first electrode 131, which is an anode, may be formed in a multi-layer structure including a transparent conductive film and an opaque conductive film with high reflectivity. The transparent conductive film may be made of a material with a relatively large work function value, such as indium tin oxide (ITO) or indium zinc oxide (IZO). The opaque conductive film may be formed in a single layer or multi-layer structure including aluminum (Al), silver (Ag), copper (Cu), lead (Pb), molybdenum (Mo), titanium (Ti), or an alloy thereof. For example, the first electrode 131 may be formed in a structure in which a transparent conductive film, an opaque conductive film, and a transparent conductive film are sequentially stacked. However, the present invention is not limited thereto, and the first electrode 131 may also be formed in a structure in which a transparent conductive film and an opaque conductive film are sequentially stacked.

[0059] A bank 117 may be disposed on the first electrode 131 and the second planarization layer 116. An opening may be formed in the bank 117 to expose the first electrode 131. The bank 117 may define a light-emitting region of the display device 100, and may therefore be referred to as a pixel defining film.

[0060] The light-emitting layer 132 is disposed on the first electrode 131. The light-emitting layer 132 may be configured to be disposed in an organic layer formed by laminating a plurality of organic material layers.

[0061] Specifically, the organic layer of the light emitting device 130 may be formed by stacking a hole injection layer (HIL), a hole transport layer (HTL), an electron blocking layer (EBL), an emitting layer (EML, 132), an electron transport layer (ETL), and an electron injection layer (EIL) on the first electrode 131 in this order or in the reverse order. Alternatively, the organic layer may include first and second organic layers facing each other with a charge generation layer interposed therebetween. In this case, one of the first and second organic layers may generate blue light, and the other of the first and second organic layers may generate yellow-green light, so that white light may be generated through the first and second organic layers. The white light generated in the organic layer may be incident on a color filter located on the organic layer to realize a color image. Alternatively, a color image may be realized by generating color light corresponding to each sub-pixel in each organic layer without a separate color filter. For example, the organic layers of the red sub-pixels may produce red light, the organic layers of the green sub-pixels may produce green light, and the organic layers of the blue sub-pixels may produce blue light.

[0062] A second electrode 133, which is a cathode, may be further disposed on the light emitting layer 132. Since the display device 100 is a top emission type display device, the second electrode 133 may be made of a very thin metal material or a transparent conductive material. The second electrode 133 of the light emitting element 130 may be disposed on the light emitting layer 132 to face the first electrode 131 with the light emitting layer 132 interposed therebetween. In the display device 100 according to an embodiment of the present invention, the second electrode 133 may be a cathode electrode. A sealing part 140 for suppressing moisture penetration may be further disposed on the second electrode 133.

[0063] The sealing unit 140 may include a first inorganic sealing layer 141, an organic sealing layer 142, and a second inorganic sealing layer 143. The first inorganic sealing layer 141 of the sealing unit 140 may be disposed on the second electrode 133. The organic sealing layer 142 may be disposed on the first inorganic sealing layer 141. The second inorganic sealing layer 143 may be disposed on the organic sealing layer 142. The first inorganic sealing layer 141 and the second inorganic sealing layer 143 of the sealing unit 140 may be formed of an inorganic material such as silicon nitride (SiNx) or silicon oxide (SiOx). The organic sealing layer 142 of the sealing unit 140 may be formed of an organic material such as an acrylic resin, an epoxy resin, a phenolic resin, a polyamide resin, and a polyimide resin.

[0064] Also, referring to FIGS. 1a to 2b, the first inorganic sealing layer 141 may include a first region 141R1 and a second region 141R2.

[0065] The first region 141R1 may overlap with the data driver DD and may be a region in which the refractive index of the first inorganic sealing layer 141 is increased.

[0066] 1b, the area of ​​the first region 141R1 may be smaller than the area of ​​the second region 141R2. The area of ​​the first region 141R1 may be 25% or less of the area of ​​the display area AA.

[0067] The second region 141R2 is a region of the first inorganic sealing layer 141 excluding the first region 141R1, and may have a lower refractive index than the first region 141R1. That is, the second region 141R2 may have the refractive index of a typical first inorganic sealing layer 141.

[0068] For example, when the refractive index of the second region 141R2, which is a typical first inorganic sealing layer 141, is 1.84, the refractive index of the first region 141R1 may be 1.85 to 2.00. Preferably, the refractive index of the first region 141R1 may be 1.89.

[0069] The method of forming the first region 141R1 and the second region 141R2 may be, for example, such that the first region 141R1 and the second region 141R2 are formed in separate layers and then patterned, and an interface may exist between the first region 141R1 and the second region 141R2, but is not limited thereto.

[0070] 4 is a graph showing a simulation of the efficiency lifetime of the blue light-emitting element of a display device according to an embodiment of the present invention and a display device of a comparative example. In FIG. 4, the X-axis is the time (h) for which the blue light-emitting layer of the blue sub-pixel emits light, and the Y-axis is the efficiency lifetime (%) of the blue light-emitting layer. At this time, the display device of the comparative example is a conventional display device in which only a second region having a lower refractive index than the first region is disposed in the first inorganic sealing layer.

[0071] Referring to FIG. 4, in the display device 100 according to one embodiment of the present invention, the first region 141R1 having an improved refractive index is disposed in the first inorganic sealing layer 141, thereby improving the efficiency life of the blue light-emitting layer.

[0072] 4, it can be seen that the efficiency life of the blue light emitting element, i.e., the blue light emitting layer, in the display device 100 according to an embodiment of the present invention is measured to be higher than that of the display device of the comparative example. Therefore, in the display device 100 according to an embodiment, the efficiency life of the blue light emitting layer can be improved by disposing the first region 141R1 having an improved refractive index in the first inorganic sealing layer 141.

[0073] On the other hand, this result may be because the light path changes due to the change in the refractive index of the first inorganic sealing layer 141, and the optimal position of the recombination zone of electrons and holes in the blue light-emitting layer, which is the most vulnerable when the light-emitting device 130 is driven, moves, thereby increasing the efficient life of the blue light-emitting layer.

[0074] In the display device 100 according to an embodiment of the present invention, the life span of the blue light emitting element is improved, thereby improving color change defects such as pinkish or yellowish.

[0075] In conventional display devices, blue light-emitting elements have a relatively short life span compared to light-emitting elements of other colors, which can cause color change defects such as pinkish or yellowish in the display device due to the blue light-emitting elements reaching the end of their life span the shortest.

[0076] Therefore, in the display device 100 according to an embodiment of the present invention, the first region 141R1 having a high refractive index is disposed in the first inorganic sealing layer 141 to change the light path, thereby increasing the efficient life of the blue light emitting layer. This can improve the life of the blue light emitting element, which is vulnerable to high temperature environments. Therefore, in the display device 100 according to an embodiment of the present invention, color change defects such as pinkish or yellowish can be improved by improving the life of the blue light emitting element.

[0077] In addition, in the display device 100 according to an embodiment of the present invention, the region where the refractive index of the first inorganic sealing layer 141 is increased is limited to a minimum, thereby improving the life span of the blue light emitting device and simultaneously realizing optimal light emitting efficiency. As described above, when the refractive index of the first inorganic sealing layer 141 is increased, the lifetime of the blue light-emitting element may be improved and color change defects may be improved; however, the increased refractive index of the first inorganic sealing layer 141 may reduce the luminous efficiency of the light-emitting elements 130 arranged throughout the display device 100.

[0078] Therefore, in the display device 100 according to an embodiment of the present invention, the first region 141R1 in which the refractive index is increased in the first inorganic encapsulating layer 141 is arranged to overlap with the data driver DD, which is a position where the most heat is generated when the display device 100 is driven, thereby improving the lifespan reduction of the blue light emitting device, which is particularly vulnerable in a high temperature environment, while preventing the light emission efficiency of other regions from being reduced. In this case, the area of ​​the first region 141R1 may be larger than the area of ​​the data driver DD so as to sufficiently cover the area where the high temperature environment is created by the data driver DD. Specifically, the first region 141R1 in which the refractive index is increased in the first inorganic encapsulating layer 141 is limited to an area of ​​25% or less of the display area AA overlapping with the data driver DD, thereby minimizing the reduction in the light emission efficiency of the light emitting device 130 in the area where the first region 141R1 is not arranged. Therefore, in the display device 100 according to an embodiment of the present invention, the area in which the refractive index of the first inorganic encapsulating layer 141 is increased is limited to a minimum, thereby improving the lifespan of the blue light emitting device and simultaneously realizing optimal light emission efficiency.

[0079] In the following, a display device 500 according to another embodiment of the present invention will be described with reference to Figs. 5a and 5b.

[0080] FIG 5a is an enlarged plan view of one pixel of a display device according to another embodiment of the present invention. FIG 5b is a cross-sectional view taken along Vb-Vb' of FIG 5a. The display device 500 of FIG 5a and FIG 5b is substantially the same as the display device 100 of FIG 1a to FIG 4 except for the position where the first region 541R1 of the first inorganic encapsulation layer 541 is disposed, and other configurations are substantially the same, so duplicated description will be omitted. In FIG 5a, for convenience of description, only the first inorganic encapsulation layer 541 is shown among various components disposed in one pixel P of the display device 500.

[0081] 5a and 5b, the pixels P in the display area AA each include three or more sub-pixels that emit different colors. Specifically, the pixels P each include a red sub-pixel SPR, a green sub-pixel SPG, and a blue sub-pixel SPB. The light emitting element 130 and the transistor 120 may be arranged corresponding to each of the red sub-pixel SPR, the green sub-pixel SPG, and the blue sub-pixel SPB.

[0082] 5a, one pixel P of the display device 500 includes only the red subpixel SPR, the green subpixel SPG, and the blue subpixel SPB, but the pixel P may further include a white subpixel, and is not limited thereto. Also, in FIG. 5a, the red subpixel SPR, the green subpixel SPG, and the blue subpixel SPB are all shown as having rectangular shapes and being arranged side by side, but the shapes and arrangements of the red subpixel SPR, the green subpixel SPG, and the blue subpixel SPB are not limited thereto.

[0083] 5b, the red subpixel SPR includes a red light emitting element 130R including a red light emitting layer 132R, the green subpixel SPG includes a green light emitting element 130G including a green light emitting layer 132G, and the blue subpixel SPB includes a blue light emitting element 130B including a blue light emitting layer 132B. Thus, the red subpixel SPR may be configured to emit red light, the green subpixel SPG may be configured to emit green light, and the blue subpixel SPB may be configured to emit blue light.

[0084] 5b, an encapsulant 540 is disposed on the plurality of light emitting elements 130. The encapsulant 540 may include a first inorganic encapsulant layer 541, an organic encapsulant layer 142, and a second inorganic encapsulant layer 143.

[0085] The first inorganic sealing layer 541 of the sealing unit 540 may be disposed on the second electrodes 133 of the plurality of light emitting elements 130. The organic sealing layer 142 may be disposed on the first inorganic sealing layer 541. The second inorganic sealing layer 143 may be disposed on the organic sealing layer 142. The first inorganic sealing layer 541 and the second inorganic sealing layer 143 of the sealing unit 540 may be formed of an inorganic material such as silicon nitride (SiNx) or silicon oxide (SiOx). The organic sealing layer 142 of the sealing unit 540 may be formed of an organic material such as an acrylic resin, an epoxy resin, a phenolic resin, a polyamide resin, and a polyimide resin.

[0086] The first inorganic sealing layer 541 may include a first region 541R1 and a second region 541R2. The refractive index of the first region 541R1 and the refractive index of the second region 541R2 may be different from each other. The first region may be disposed to overlap one of a plurality of sub-pixels disposed in one pixel P.

[0087] Specifically, the first region 541R1 may be a region overlapping with the blue subpixel SPB and having an increased refractive index in the first inorganic sealing layer 541. The second region 541R2 may be a region of the first inorganic sealing layer 541 excluding the first region 541R1 and may have a lower refractive index than the first region 541R1. That is, the second region 541R2 may have a refractive index of a general first inorganic sealing layer 541. For example, when the refractive index of the second region 541R2, which is a general first inorganic sealing layer 541, is 1.84, the refractive index of the first region 541R1 may be 1.85 to 2.00. More preferably, the refractive index of the first region 541R1 may be 1.89.

[0088] 5a and 5b, the first region 541R1 is disposed to overlap with the blue subpixel SPB. The red and green subpixels SPR and SPG, which emit a color different from the blue subpixel, are disposed to overlap with the second region 541R2, which is the region excluding the first region 541R1. That is, the first region 541R1 may be disposed only in the region overlapping with the blue subpixel SPB among the subpixels SPR, SPG, and SPB.

[0089] The first region 541R1 and the second region 541R2 may be formed, for example, by a method in which the first region 541R1 and the second region 541R2 are formed in separate layers and then patterned. Thus, an interface may exist between the first region 541R1 and the second region 541R2, but the method of forming the first region 541R1 and the second region 541R2 is not limited thereto.

[0090] 5a and 5b, in a display device 500 according to another embodiment of the present invention, a first region 541R1 having an increased refractive index is disposed in an area of ​​the first inorganic sealing layer 541 overlapping with the blue sub-pixel SPB, thereby improving the efficiency life of the blue light-emitting layer 132B.

[0091] Specifically, in the display device 500 according to another embodiment of the present invention, the first region 541R1 having an increased refractive index is disposed in the first inorganic encapsulation layer 541 in a region overlapping with the blue subpixel SPB, so that the path of light may also change as the refractive index of the first inorganic encapsulation layer 541 changes. As a result, when the light emitting element 130 is driven, the optimal position of the recombination region of electrons and holes in the most vulnerable blue light emitting layer 132B moves, so that the efficient life of the blue light emitting layer 132B may also be improved. Therefore, in the display device 500 according to another embodiment of the present invention, the first region 541R1 having an increased refractive index is disposed in a region overlapping with the blue subpixel SPB of the first inorganic encapsulation layer 541, so that the efficient life of the blue light emitting layer 132B may also be improved.

[0092] In the display device 500 according to another embodiment of the present invention, the refractive index is increased only in the region of the first inorganic sealing layer 541 overlapping with the blue sub-pixel SPB, thereby improving color change defects such as pinkish or yellowish.

[0093] In conventional display devices, blue light-emitting elements have a relatively short lifespan compared to light-emitting elements of other colors and are vulnerable to high temperature environments, which causes the lifespan of the blue light-emitting elements to expire the fastest, resulting in color change defects such as pinkish or yellowish in the display device.

[0094] Therefore, in the display device 500 according to another embodiment of the present invention, the first region 541R1 having a high refractive index is disposed only in the region of the first inorganic encapsulation layer 541 overlapping with the blue sub-pixel SPB, thereby changing the path of light and increasing the effective life of the blue light emitting layer 132B. As a result, the life of the blue light emitting element 130B, which has a relatively low life and is vulnerable to high temperature environments compared to the light emitting elements 130R and 130G of other colors, can be improved, and the difference in life between the light emitting elements 130R and 130G of other colors and the blue light emitting element 130B can be compensated for. Therefore, in the display device 500 according to another embodiment of the present invention, the refractive index is increased only in the region of the first inorganic encapsulation layer 541 overlapping with the blue sub-pixel SPB, thereby improving color change defects such as pinkish or yellowish.

[0095] In addition, in the display device 500 according to another embodiment of the present invention, the area where the refractive index of the first inorganic sealing layer 541 is increased is limited to a minimum, thereby improving the life span of the blue light emitting device 130B and simultaneously realizing optimal light emitting efficiency.

[0096] As described above, when the refractive index of the first inorganic sealing layer 541 is increased, the life span of the blue light-emitting element 130B may be improved and color change defects may be improved; however, the increased refractive index of the first inorganic sealing layer 541 may reduce the luminous efficiency of the light-emitting elements 130 arranged throughout the display device 500.

[0097] Therefore, in the display device 500 according to another embodiment of the present invention, the first region 541R1 having an increased refractive index in the first inorganic sealing layer 541 is disposed only in a region overlapping with the blue light emitting element 130B having a relatively short life span compared to the light emitting elements 130 of other colors when the display device 500 is driven, thereby improving the reduction in life span of the blue light emitting element 130B which is particularly vulnerable in a high temperature environment and has a relatively short life span, while preventing the reduction in the luminous efficiency of other regions. Therefore, in the display device 500 according to another embodiment of the present invention, the region having an increased refractive index in the first inorganic sealing layer 541 is limited to a minimum, thereby improving the life span of the blue light emitting element 130B and simultaneously realizing optimal luminous efficiency.

[0098] Display devices according to various embodiments of the present invention can be described as follows.

[0099] A display device according to an embodiment of the present invention includes a display area in which a plurality of pixels are arranged, a substrate including a non-display area having a bending area extending and bending from one side of the display area and a first non-display area extending from the bending area, a plurality of transistors and a plurality of light-emitting elements arranged on the substrate corresponding to each of the plurality of pixels, an encapsulation part arranged on the plurality of light-emitting elements and including a first inorganic encapsulation layer, an organic encapsulation layer and a second inorganic encapsulation layer, and a data driver arranged in the first non-display area and transmitting a signal to the display area, wherein the substrate is bent at the bending area and the first non-display area is arranged below the display area, and the first inorganic encapsulation layer includes a first area overlapping with the data driver and a second area excluding the first area and having a refractive index lower than that of the first area.

[0100] According to another feature of the invention, the area of ​​the first region may be smaller than the area of ​​the second region.

[0101] According to another aspect of the present invention, the area of ​​the first region may be 25% or less of the area of ​​the display region.

[0102] According to another feature of the present invention, the refractive index of the first region may be 1.85 to 2.00.

[0103] According to another aspect of the present invention, an area of ​​the first region may be larger than an area of ​​the data driver.

[0104] According to another aspect of the invention, the first and second regions may be formed in separate layers, with an interface between the first and second regions.

[0105] According to another aspect of the present invention, a display panel includes a display area where an image is displayed, a non-display area surrounding the display area and a bending area extending from the non-display area, a plurality of light-emitting elements arranged in the display area, a first inorganic encapsulating layer arranged on the plurality of light-emitting elements, an organic encapsulating layer arranged on the first inorganic encapsulating layer, a second inorganic encapsulating layer arranged on the organic encapsulating layer, and a data driver connected to the bending area and arranged on a rear surface of the display panel to transmit a signal to the display panel, wherein the first inorganic encapsulating layer includes a first region arranged corresponding to the data driver and a second region having a lower refractive index than the first region.

[0106] According to another aspect of the present invention, the first region may be disposed with an area of ​​25% or less of the area of ​​the display region.

[0107] According to yet another feature of the present invention, the first region may have a refractive index of 1.85 to 2.00.

[0108] According to another aspect of the present invention, the first region and the second region may be disposed separately, and an interface may exist between the first region and the second region.

[0109] According to another aspect of the present invention, the first region may be disposed in an area larger than the size of the data driver.

[0110] According to another feature of the present invention, there is provided a substrate including a display region in which a plurality of pixels are arranged, each of which includes three or more sub-pixels emitting different colors from each other, and a non-display region surrounding the display region; a plurality of transistors and a plurality of light-emitting elements arranged corresponding to each of the sub-pixels; and a sealing portion arranged on the plurality of light-emitting elements, the sealing portion including a first inorganic sealing layer, an organic sealing layer, and a second inorganic sealing layer, the first inorganic sealing layer including a first region overlapping with any one of the three or more sub-pixels emitting different colors from each other, and a second region excluding the first region and having a refractive index different from that of the first region.

[0111] According to another aspect of the present invention, the sub-pixel overlapping with the first region is a blue sub-pixel that emits blue light.

[0112] According to another feature of the present invention, the sub-pixel that emits light of a color different from the blue sub-pixel overlaps with a second region of the first inorganic sealing layer.

[0113] According to yet another feature of the invention, the refractive index of the second region may be less than the refractive index of the first region.

[0114] According to yet another feature of the present invention, the first region may have a refractive index of 1.85 to 2.00.

[0115] According to another aspect of the present invention, the first region and the second region are disposed separately from each other, and an interface may exist between the first region and the second region.

[0116] Although the embodiments of the present invention have been described in detail above with reference to the accompanying drawings, the present invention is not necessarily limited to these embodiments, and various modifications can be made within the scope of the technical idea of ​​the present invention. Therefore, the embodiments disclosed in the present invention are for illustration purposes, not for limiting the technical idea of ​​the present invention, and the scope of the technical idea of ​​the present invention is not limited by these embodiments. Therefore, it should be understood that the embodiments described above are illustrative and not restrictive in all respects. 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 substrate including a display area in which a plurality of pixels are arranged, a bending area extending from one side of the display area and curved, and a first non-display area extending from the bending area; a plurality of transistors and a plurality of light-emitting elements arranged on the substrate corresponding to the plurality of pixels, a sealing portion disposed on the plurality of light-emitting elements, the sealing portion including a first inorganic sealing layer, an organic sealing layer, and a second inorganic sealing layer; a data driver disposed in the first non-display region and configured to transmit a signal to the display region; the substrate is bent at the bending region such that the first non-display region is disposed below the display region; The first inorganic sealing layer includes a first region overlapping the data driver, and a second region other than the first region, the second region having a lower refractive index than the first region.

2. The display device according to claim 1 , wherein an area of ​​the first region is smaller than an area of ​​the second region.

3. The display device according to claim 2 , wherein an area of ​​the first region is 25% or less of an area of ​​the display region.

4. 2. The display device according to claim 1, wherein the refractive index of the first region is 1.85 to 2.

00.

5. The display device of claim 1 , wherein an area of ​​the first region is greater than an area of ​​the data driver.

6. The display device according to claim 1 , wherein the first region and the second region are formed in separate layers, and an interface exists between the first region and the second region.

7. a display panel including a display area in which an image is displayed, a non-display area surrounding the display area, and a bending area extending from the non-display area; A plurality of light-emitting elements arranged in the display area; A first inorganic sealing layer disposed on the plurality of light emitting elements; an organic sealing layer disposed on the first inorganic sealing layer; a second inorganic sealing layer disposed on the organic sealing layer; and a data driver connected to the bending region and disposed on a rear surface of the display panel to transmit a signal to the display panel; The first inorganic encapsulation layer includes a first region disposed corresponding to the data driver and a second region having a refractive index lower than that of the first region.

8. The display device according to claim 7 , wherein the first region is disposed with an area that is 25% or less of an area of ​​the display region.

9. 8. The display device according to claim 7, wherein the first region has a refractive index of 1.85 to 2.

00.

10. The first region and the second region are disposed separately from each other, The display device according to claim 7 , wherein an interface exists between the first region and the second region.

11. The display device of claim 7 , wherein the first region is disposed in an area larger than a size of the data driver.

12. a substrate including a display area in which a plurality of pixels are arranged, each of the pixels including three or more sub-pixels that emit light of different colors; and a non-display area surrounding the display area; A plurality of transistors and a plurality of light-emitting elements arranged corresponding to each of the sub-pixels; and a sealing portion disposed on the plurality of light emitting elements, the sealing portion including a first inorganic sealing layer, an organic sealing layer, and a second inorganic sealing layer; The first inorganic sealing layer is a first region overlapping any one of the three or more sub-pixels that emit light of different colors; and A display device comprising a second region, the second region being a region other than the first region and having a refractive index different from that of the first region.

13. The display device according to claim 12 , wherein the sub-pixel overlapping the first region is a blue sub-pixel that emits blue light.

14. The display device of claim 13 , wherein a subpixel that emits light of a color different from that of the blue subpixel overlaps with the second region of the first inorganic sealing layer.

15. The display device of claim 12 , wherein the refractive index of the second region is lower than the refractive index of the first region.

16. The display device according to claim 12, wherein the first region has a refractive index of 1.85 to 2.

00.

17. The first region and the second region are disposed separately from each other, The display device according to claim 12 , wherein an interface exists between the first region and the second region.

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