Optical improvement layer and display device with optical improvement layer

Abstract

This disclosure provides a display device including a display panel with pixels and an optical improvement layer on the display panel. The optical improvement layer includes a first pattern layer and a second pattern layer that overlap each other. The first pattern layer has a first refractive index, and the second pattern layer has a second refractive index different from the first refractive index. The first pattern layer has an average pattern size larger than that of the second pattern layer, and the average pattern ratio of the patterns included in the first pattern layer is less than the average pattern ratio of the patterns included in the second pattern layer. Furthermore, another embodiment of this disclosure provides an optical improvement layer.

Description

[0001] Cross-reference to related applications

[0002] This application claims priority to Korean Patent Application No. 10-2024-0200134, filed on December 30, 2024, the entire contents of which are incorporated herein by reference. Technical Field

[0003] This disclosure relates to a display device including an optical improvement layer, which can prevent or suppress sandy phenomena caused by external light and sparkling phenomena caused by internal light sources. Background Technology

[0004] Organic light-emitting diode (OLED) displays have attracted attention as the next generation of flat panel displays because, as self-emissive devices that do not require a separate light source, OLED displays feature fast response times, low power consumption, and excellent viewing angles. Furthermore, OLED displays offer the advantage of being easily adaptable to flexible displays.

[0005] Display devices include display panels that display images. In addition, a light-transmitting cover substrate is typically disposed on the display surface of the display panel. The cover substrate can be surface-treated to prevent glare.

[0006] To prevent glare perceived from the cover substrate, irregular micropatterns can be formed on it. When such irregular patterns are arranged, the irregularity or non-uniformity caused by the irregular arrangement of multiple patterns may cause sparkling when the light-emitting element emits light. Sparkling refers to the irregular appearance of bright and dark areas on the display surface, manifesting as spots corresponding to the intervals between patterns.

[0007] Meanwhile, when light is incident from outside the display device (external light incident), reflection and refraction occur in the layers that make up the cover substrate and the display panel. Due to fluctuations in the reflected or refracted light, a blurry area that looks like sand sprinkled on the surface may appear near the location where the reflected external light is detected. This phenomenon is called the sandy effect.

[0008] If flickering or a grainy or sand-like phenomenon occurs, the display quality of the display device may deteriorate. Therefore, it is necessary to prevent flickering or a grainy or sand-like phenomenon in display devices. Summary of the Invention

[0009] One embodiment of this disclosure provides a display device that can effectively overcome flickering or sand-like phenomena.

[0010] One embodiment of this disclosure provides a display device that can effectively suppress flickering when the internal light-emitting element emits light (in an on state) and graininess when external light is reflected on the display surface.

[0011] One embodiment of this disclosure provides a technique for effectively overcoming flickering or graininess in a display device by providing an optical improvement layer on a display panel, the optical improvement layer including a first pattern layer and a second pattern layer with different pattern shapes.

[0012] One embodiment of this disclosure provides a display device that can prevent flickering or sand-like phenomena due to having an optical improvement layer that can effectively suppress flickering or sand-like phenomena.

[0013] One embodiment of this disclosure provides an optical sheet that can effectively suppress flickering or graininess in a display device.

[0014] One embodiment of this disclosure for addressing the aforementioned technical problem provides a display device comprising a display panel having pixels and an optical improvement layer on the display panel, wherein the optical improvement layer comprises a first pattern layer and a second pattern layer overlapping each other, the first pattern layer having a first refractive index, the second pattern layer having a second refractive index different from the first refractive index, the first pattern layer having an average pattern size greater than that of the second pattern layer, and the average pattern ratio of the patterns contained in the first pattern layer being less than the average pattern ratio of the patterns contained in the second pattern layer.

[0015] The average pattern size is the average of the maximum diameters of the corresponding patterns in the planar images of the first and second pattern layers, respectively. The pattern ratio is calculated as b / a, where a represents the maximum diameter of each pattern and b represents the height of the pattern. The average pattern ratio is calculated as the average of the pattern ratios of multiple patterns.

[0016] The first pattern layer can have multiple lens patterns.

[0017] The second pattern layer may include multiple patterns having horn-shaped shapes.

[0018] The optical enhancement layer may also be included in an intermediate layer on the first patterning layer.

[0019] The intermediate layer may contact the first patterned layer, and the first patterned layer and the intermediate layer may have a refractive index difference of 0.05 to 0.1.

[0020] The intermediate layer can contact the first patterned layer and the second patterned layer, and the refractive index difference between the intermediate layer and the second patterned layer can be 0.01 or less.

[0021] The intermediate layer can be made of the same material as the second patterned layer.

[0022] The intermediate layer can be formed integrally with the second pattern layer.

[0023] The first patterned layer and the second patterned layer can have a refractive index difference of 0.05 to 0.1.

[0024] The optical enhancement layer may also include a fill layer on the second patterning layer.

[0025] The filler layer contacts the second patterned layer, and the second patterned layer and the filler layer may have a refractive index difference of 0.05 to 0.1.

[0026] Intermediate layers and fill layers can be placed between the first pattern layer and the second pattern layer.

[0027] The intermediate layer and the filler layer can be made of the same material.

[0028] The optical enhancement layer may also include spacers disposed between the intermediate layer and the filler layer.

[0029] A fill layer can be placed between the first pattern layer and the second pattern layer.

[0030] The filler layer can be formed integrally with the first pattern layer.

[0031] The first pattern layer can contact the second pattern layer, and the protrusions of the first pattern layer and the protrusions of the second pattern layer can protrude in opposite directions.

[0032] The first pattern layer and the second pattern layer can be formed integrally.

[0033] The refractive index difference between the first patterned layer and the intermediate layer can be the same as the refractive index difference between the second patterned layer and the filler layer.

[0034] The display device also includes a cover substrate on the fill layer, and the fill layer may have the same refractive index as the cover substrate.

[0035] The display panel includes an outer coating layer, a first pattern layer disposed on the outer coating layer, and the outer coating layer may have the same refractive index as the first pattern layer.

[0036] The display panel includes a color filter layer, and an optical enhancement layer can be disposed on the color filter layer.

[0037] Another embodiment of this disclosure provides an optical improvement layer comprising a first pattern layer and a second pattern layer that overlap each other, wherein the first pattern layer has a first refractive index, the second pattern layer has a second refractive index different from the first refractive index, the first pattern layer has an average pattern size larger than that of the second pattern layer, and the average pattern ratio of the patterns contained in the first pattern layer is less than the average pattern ratio of the patterns contained in the second pattern layer. Attached Figure Description

[0038] Other objects, features, and advantages of this disclosure will become clearer from the following detailed description taken in conjunction with the accompanying drawings:

[0039] Figure 1 This is a schematic diagram of a display device according to one embodiment of the present disclosure.

[0040] Figure 2 This is a schematic diagram of one implementation of a display panel.

[0041] Figure 3 yes Figure 2 The diagram shows a planar representation of the pixel structure.

[0042] Figure 4 yes Figure 3 A cross-sectional view of the structure of a sub-pixel.

[0043] Figure 5 yes Figure 4 A partial cross-sectional view of the optical improvement layer.

[0044] Figure 6A This is a plan view of the first pattern layer. Figure 6B It is a plan view of the second pattern layer.

[0045] Figure 7A and Figure 7B This is a schematic diagram explaining the mechanism for eliminating flickering.

[0046] Figure 8A and Figure 8B This is a schematic diagram explaining the mechanism for eliminating sand particles.

[0047] Figure 9 This is a partial cross-sectional view of a display device according to another embodiment of the present disclosure.

[0048] Figures 10 to 16 These are partial cross-sectional views of an optical improvement layer applied to a display device according to another embodiment of this disclosure.

[0049] Figure 17A This is a partial cross-sectional view of the display device based on Comparative Example 1. Figure 17B This is a partial cross-sectional view of the display device based on Comparative Example 2.

[0050] Figure 18 The image shows the elimination of flickering and sand-like phenomena.

[0051] Figures 19A to 19H This is a schematic cross-sectional view illustrating a method for manufacturing an optical enhancement layer according to one embodiment of the present disclosure.

[0052] Figures 20A to 20C This is a schematic perspective view showing a method for manufacturing a first roller, which is used to form a first pattern layer.

[0053] Figures 21A to 21C This is a schematic perspective view showing a method for manufacturing a second roller, which is used to form a second pattern layer. Detailed Implementation

[0054] The advantages and features of this disclosure, as well as the methods for implementing them, will become clearer with reference to the detailed description of the embodiments described below and the accompanying drawings. However, this disclosure is not limited to the embodiments disclosed below, but can be implemented in various different forms. These embodiments are provided only to ensure that the disclosure is complete and to inform those skilled in the art of the scope of the invention.

[0055] The shapes, dimensions, ratios, angles, numbers, etc., disclosed in the accompanying drawings for explaining the embodiments of this disclosure are merely illustrative, and this disclosure is not limited to the details depicted in the drawings. Throughout the specification, the same components may be represented by the same reference numerals. Furthermore, in describing this disclosure, detailed descriptions of related known technologies will be omitted if they are deemed unnecessarily obscuring the spirit of this disclosure.

[0056] In this specification, when the words “comprising,” “having,” and “consisting of” are used, additional parts may be added unless the expression “only” is used. When a part is represented in the singular, the plural is included unless otherwise expressly stated.

[0057] When interpreting a composition, it is interpreted as including a range of errors, even without a separate explicit description.

[0058] For example, when the positional relationship between two parts is described as "on top of," "above," "below," "next to," etc., one or more other parts may be located between the two parts unless the expressions "immediately following" or "directly" are used.

[0059] Spatial relative terms such as “below,” “under,” “lower,” “above,” and “upper” can be used to readily describe the relationship between one element or component and other elements or components as depicted in the accompanying drawings. In addition to the orientations depicted in the drawings, spatial relative terms should be understood to include different orientations of the elements during use or operation. For example, if an element depicted in the drawings is flipped, an element described as “below” or “under” another element may end up “above” another element. Thus, the exemplary term “below” can include both below and above directions. Similarly, the exemplary term “above” can include both above and below directions.

[0060] When describing temporal relationships, for example, when temporal continuity is described as “after,” “after,” “next to,” or “before,” discontinuous cases can also be included, as long as the expressions “immediately” or “directly” are not used.

[0061] Although terms such as "first" and "second" are used to describe various components, these components are not limited by these terms. These terms are only used to distinguish one component from another. Therefore, within the scope of this disclosure, the "first" component mentioned below can also be the "second" component.

[0062] The term "at least one" should be understood to include all possible combinations of one or more related items. For example, "at least one of the first, second, and third items" can mean not only the first, second, or third item, but also any combination of items that can be represented by two or more of the first, second, and third items.

[0063] Features of each of the various embodiments of this disclosure may be combined in part or in whole or in combination with each other, and various technical connections and operations are possible, and the various embodiments may be implemented independently of each other or together in a related relationship.

[0064] When adding reference numerals to components in each figure describing embodiments of the present disclosure, the same components may have the same reference numerals whenever possible, even if they are shown in different figures.

[0065] In the following description, examples of this disclosure will be illustrated with reference to the accompanying drawings and examples. For ease of explanation, the components shown in the drawings are at different scales than actual scales, and therefore the scope is not limited to the scales shown in the drawings.

[0066] Figure 1 This is a schematic diagram of a display device 100 according to one embodiment of the present disclosure. All components of the various display devices according to all embodiments of the present disclosure are operatively coupled and constructed.

[0067] A display device 100 according to one embodiment of the present disclosure may include a display panel 310, a gate driver 320, a data driver 330, and a control unit 340, such as Figure 1 As shown.

[0068] Gate lines GL and data lines DL are disposed on the display panel 310, and pixel P is arranged at the intersection of gate lines GL and data lines DL. Images are displayed by driving pixel P.

[0069] The control unit 340 controls the gate driver 320 and the data driver 330.

[0070] The control unit 340 uses signals provided from an external system (not shown) to output a gate control signal GCS for controlling the gate driver 320 and a data control signal DCS for controlling the data driver 330. Furthermore, the control unit 340 samples input image data from the external system, rearranges the image data, and provides the rearranged digital image data (RGB) to the data driver 330.

[0071] The gate control signal GCS includes the gate start pulse (GSP), gate shift clock (GSC), gate output enable signal (GOE), start signal (Vst), and gate clock (GCLK). Furthermore, the gate control signal GCS may include control signals for controlling the shift register 350.

[0072] The data control signal DCS includes the source start pulse (SSP), the source shift clock signal (SSC), the source output enable signal (SOE), and the polarity control signal (POL).

[0073] The data driver 330 supplies data voltage to the data line DL of the display panel 310. Specifically, the data driver 330 converts the image data RGB input from the control unit 340 into analog data voltage and supplies the data voltage to the data line DL.

[0074] Gate driver 320 may include shift register 350.

[0075] The shift register 350 sequentially provides gate pulses to the gate line GL within a frame using a start signal and gate clock sent from the control unit 340. Here, a frame refers to a period of time during which an image is output through the display panel 310. The gate pulses have an on-state voltage capable of turning on the switching elements (thin-film transistors) disposed in the pixel P.

[0076] Additionally, during the remaining period of a frame when no gate pulse is supplied, shift register 350 supplies a gate turn-off signal to gate line GL, which can turn off the switching element. In the following text, the gate pulse and the gate turn-off signal are collectively referred to as the scan signal (SS or Scan).

[0077] According to one embodiment of this disclosure, the gate driver 320 can be mounted on the display panel 310. In this way, the structure in which the gate driver 320 is directly mounted on the display panel 310 is called a gate in panel (GIP) structure.

[0078] The gate driver 320 may include multiple thin-film transistors. These multiple thin-film transistors may be disposed in the shift register 350.

[0079] Figure 2 This is a schematic diagram of one embodiment of the display panel 310. As an example of the display panel 310 applied to the display device 100, Figure 2 An organic light-emitting panel is shown. The product includes an organic light-emitting panel. Figure 1 The display device 100 can be referred to as an organic light-emitting display device.

[0080] Reference Figure 2 The display panel 310 includes a substrate 110 and pixels P on the substrate 110.

[0081] A glass substrate or a plastic substrate can be used as substrate 110. Substrate 110 may include a display area AA and a non-display area IA.

[0082] The display area AA is the area where an image is displayed, and may also be referred to as the pixel array area, effective area, pixel array unit, display unit, or screen. The display area AA includes multiple pixels P.

[0083] Multiple pixels P can be arranged along a first direction X and a second direction Y intersecting the first direction X. For example, the first direction X may be referred to as the first length direction, the long side length direction, the horizontal direction, or the first horizontal direction of the substrate 110. In addition, the second direction Y may be referred to as the second length direction, the short side length direction, the vertical direction, or the second horizontal direction of the substrate 110.

[0084] Each of the plurality of pixels P can be a unit region that actually emits light. For example, the plurality of pixels P can be configured to have a pixel pitch (PP) along a first direction X; see Figure 3 For example, the pixel pitch PP can be defined as the size of each of the multiple pixels P in the first direction X, the distance between one side of two adjacent pixels P along the first direction X, or the distance between the centers of two adjacent pixels P along the first direction X.

[0085] Each of a plurality of pixels P may include a plurality of adjacent subpixels SP. For example, a plurality of subpixels SP may constitute a pixel P.

[0086] A non-display area IA is an area where no image is displayed. A non-display area IA can include at least one of a peripheral circuit area, a signal supply area, an invalid area, and a border area. A non-display area IA may also be referred to as, for example, a peripheral circuit area, a signal supply area, an invalid area, or a border area.

[0087] The non-display area IA can be configured to surround the display area AA. The display panel 310 may include a gate driver 320 disposed on the non-display area IA of the substrate 110. The gate driver 320 may also be referred to as peripheral circuitry. The gate driver 320 may be disposed on both sides of the substrate 110.

[0088] Figure 3 yes Figure 2 The diagram shows a planar representation of the structure of pixel P. Figure 2 and Figure 3 In the diagram, the X-axis represents the horizontal direction, the Y-axis represents the vertical direction, and the Z-axis represents the thickness direction.

[0089] Reference Figure 2 and Figure 3 In the display panel 310 of the display device 100 according to one embodiment of the present disclosure, each of the plurality of pixels P may include, for example, four sub-pixels SP1, SP2, SP3, SP4. However, the embodiments of the present disclosure are not limited thereto, and different numbers of sub-pixels may also be used.

[0090] In one embodiment of this disclosure, a pixel P may include a first sub-pixel SP1, a second sub-pixel SP2, a third sub-pixel SP3, and a fourth sub-pixel SP4 that are adjacent to each other along a first direction X. For example, each of the plurality of pixels P may include a first red sub-pixel SP1, a second white sub-pixel SP2, a third green sub-pixel SP3, and a fourth blue sub-pixel SP4, but the embodiments of this disclosure are not limited thereto. According to one embodiment of this disclosure, each of the first sub-pixel SP1 to the fourth sub-pixel SP4 may be configured to have different sizes or areas.

[0091] Each of the first sub-pixel SP1, the second sub-pixel SP2, the third sub-pixel SP3, and the fourth sub-pixel SP4 may include a light-emitting area EA and a circuit area CA.

[0092] The light-emitting region EA can be located on one side of the sub-pixel region, such as the upper side. The light-emitting regions EA of the first sub-pixel SP1, the second sub-pixel SP2, the third sub-pixel SP3, and the fourth sub-pixel SP4 can each have different sizes or areas. According to one embodiment of this disclosure, the light-emitting region EA can also be referred to as the aperture region or the light-emitting region.

[0093] According to one embodiment of this disclosure, among the light-emitting regions EA of the first sub-pixel SP1, the second sub-pixel SP2, the third sub-pixel SP3, and the fourth sub-pixel SP4, the light-emitting region EA of the second sub-pixel SP2 can have the largest size, and the light-emitting region EA of the fourth sub-pixel SP4 can have the smallest size. The light-emitting region EA of the first sub-pixel SP1 can be smaller than the light-emitting region EA of the second sub-pixel SP2, and can have a larger size than the light-emitting regions EA of the third sub-pixel SP3 and the fourth sub-pixel SP4. Furthermore, the size of the light-emitting region EA of the third sub-pixel SP3 can be larger than the size of the light-emitting region EA of the fourth sub-pixel SP4. However, the embodiments of this disclosure are not limited thereto.

[0094] According to one embodiment of this disclosure, in each of the first sub-pixel SP1, the second sub-pixel SP2, the third sub-pixel SP3, and the fourth sub-pixel SP4, the circuit region CA can be spatially separated from the light-emitting region EA. For example, the circuit region CA can be located on the opposite side or below the sub-pixel region. For example, the circuit region CA can be a non-light-emitting region or a non-aperture region. However, embodiments of this disclosure are not limited thereto.

[0095] At least a portion of the circuit region CA may overlap with the light-emitting region EA. For example, in each sub-pixel SP1, SP2, SP3, SP4, the circuit region CA may overlap with the entire light-emitting region EA or be disposed below the light-emitting region EA. According to one embodiment of this disclosure, the light-emitting region EA may extend above the circuit region CA, and the entire circuit region CA may overlap with the light-emitting region EA.

[0096] Although not shown in the figure, each of the plurality of pixels P may further include a light-transmitting area surrounding at least one of the light-emitting area EA and circuit area CA of each of the first sub-pixel SP1, the second sub-pixel SP2, the third sub-pixel SP3, and the fourth sub-pixel SP4. For example, each of the plurality of pixels P may include a pixel-specific light-emitting area EA corresponding to each of the plurality of sub-pixels SP1 to SP4, and a light-transmitting area surrounding each of the plurality of sub-pixels SP1 to SP4. In this case, due to light transmission through the light-transmitting area, the display device 100 can realize a transparent display device. A transparent display device including an organic light-emitting panel may be referred to as a transparent organic light-emitting display device.

[0097] Reference Figure 3 Two data lines DL extending along the second direction Y can be arranged parallel to each other between the first sub-pixel SP1 and the second sub-pixel SP2, and between the third sub-pixel SP3 and the fourth sub-pixel SP4. A gate line GL extending along the first direction X can be arranged between the light-emitting region EA and the circuit region CA of each of the first sub-pixels SP1 to SP4. A pixel power line PL extending along the second direction Y can be arranged on one side of the first sub-pixel SP1 or the fourth sub-pixel SP4. A reference line RL extending along the second direction Y can be arranged between the second sub-pixel SP2 and the third sub-pixel SP3. The reference line RL can be used as a sensing line to externally sense changes in the characteristics of the driving thin-film transistors and / or the characteristics of the light-emitting element layer arranged in the circuit region CA when pixel P is in sensing drive mode.

[0098] Figure 4 yes Figure 3 A cross-sectional view of the structure of a sub-pixel SP.

[0099] Reference Figure 3 and Figure 4 According to one embodiment of the present disclosure, a display device 100 includes a display panel 310 and an optical enhancement layer 210 on the display panel 310. The display panel 310 includes pixels P. The display panel 310 may include a substrate 110, a pixel circuit layer PCL, an organic light-emitting element 160, and an encapsulation layer 180.

[0100] The substrate 110 may also be referred to as a first substrate, a base substrate, a lower substrate, a glass substrate, a plastic substrate, or a substrate member. According to one embodiment of this disclosure, glass or plastic can be used as the substrate 110. Flexible, transparent plastics, such as polyimide, can be used as the plastic. When polyimide is used as the substrate 110, considering the high-temperature deposition process performed on the substrate 110, a heat-resistant polyimide capable of withstanding high temperatures can be used.

[0101] The pixel circuit layer PCL can be disposed on the substrate 110. The pixel circuit layer PCL may include a buffer layer 112, pixel circuits, and a protective layer 118.

[0102] The buffer layer 112 may be disposed on the first surface or the entire upper surface of the substrate 110. The buffer layer 112 may be used to prevent materials contained in the substrate 110 from diffusing into the transistor layer during the high-temperature processing of the thin-film transistor manufacturing process, or to prevent external moisture or water vapor from penetrating toward the organic light-emitting element 160. Optionally, the buffer layer 112 may be omitted.

[0103] The pixel circuit may include a driving thin-film transistor Tdr disposed in the circuit region CA of each sub-pixel SP. The driving thin-film transistor Tdr may include an active layer 113, a gate insulating layer 114, a gate electrode 115, an interlayer insulating layer 116, a drain electrode 117a, and a source electrode 117b.

[0104] The active layer 113 may include a semiconductor material based on any one of amorphous silicon, polycrystalline silicon, oxide, and organic materials. The active layer 113 may include a channel 113c, a drain region 113d, and a source region 113s.

[0105] The gate insulating layer 114 may be disposed on the active layer 113. The gate insulating layer 114 may be disposed in an island shape only on the channel portion 113c of the active layer 113, or it may be disposed on the entire upper surface of the substrate 110 or the buffer layer 112 including the active layer 113.

[0106] The gate electrode 115 can be disposed on the gate insulating layer 114 so as to overlap with the channel portion 113c of the active layer 113.

[0107] Interlayer insulating layer 116 may be formed on gate electrode 115 and drain region 113d and source region 113s of active layer 113. Interlayer insulating layer 116 may be formed on the entire upper surface of substrate 110 or buffer layer 112. For example, interlayer insulating layer 116 may be made of inorganic or organic materials.

[0108] Drain electrode 117a can be disposed on interlayer insulating layer 116 so as to be electrically connected to drain region 113d of active layer 113. Source electrode 117b can be disposed on interlayer insulating layer 116 so as to be electrically connected to source region 113s of active layer 113.

[0109] In addition to the driving thin-film transistor Tdr and at least one switching thin-film transistor, the pixel circuit may also include at least one capacitor disposed in the circuit region CA.

[0110] A display device 100 according to one embodiment of the present disclosure may further include a light-shielding layer 111. The light-shielding layer 111 may be disposed on the substrate 110 to overlap with the active layer 113, for minimizing or preventing changes in the threshold voltage of the thin-film transistor due to external light. According to the present disclosure, the light-shielding layer 111 may be disposed below the active layer 113 that drives the thin-film transistor Tdr or switches the thin-film transistor.

[0111] A protective layer 118 may be disposed above the pixel circuitry. For example, the protective layer 118 may be configured to surround the drain electrode 117a and source electrode 117b of the driving thin-film transistor Tdr, as well as the interlayer insulating layer 116. For example, the protective layer 118 may be formed of an inorganic insulating material. The protective layer 118 may also be referred to as a passivation layer or an interlayer insulating layer.

[0112] The planarization layer 130 can be disposed on the pixel circuit layer PCL. The planarization layer 130 can be formed in the remaining areas of the entire display area AA and non-display area IA, excluding the pad areas. For example, the planarization layer 130 may include an extension extending from the display area AA toward the remaining non-display area IA excluding the pad areas. Therefore, the planarization layer 130 can have a size larger than the display area AA.

[0113] According to one embodiment of this disclosure, the planarization layer 130 may be formed to have a relatively thick thickness to provide a flat surface 130a on the pixel circuit layer PCL. For example, the planarization layer 130 may be made of an organic material.

[0114] The organic light-emitting element 160 can be disposed in the light-emitting region EA of each sub-pixel SP. According to one embodiment of the present disclosure, the organic light-emitting element 160 may include a first electrode E1, a light-emitting layer EL, and a second electrode E2.

[0115] According to one embodiment of the present disclosure, the first electrode E1, the light-emitting layer EL, and the second electrode E2 can be configured to emit light toward the opposite side of the substrate 110 according to the top emission method, or can be configured to emit light toward the substrate 110 according to the bottom emission method.

[0116] In the following description, embodiments of the present disclosure will be described, with a focus on a display device 100 including an organic light-emitting element 160 configured according to a top-emitting method to emit light toward the opposite side of a substrate 110.

[0117] The first electrode E1 can be formed on the planarization layer 130 of the sub-pixel region SPA and can be electrically connected to the source electrode 117b of the driving thin-film transistor Tdr. One end of the first electrode E1 adjacent to the circuit region CA can be electrically connected to the source electrode 117b of the driving thin-film transistor Tdr through the electrode contact hole CH provided in the planarization layer 130 and the protective layer 118.

[0118] The light-emitting layer EL can be formed on the first electrode E1 and can directly contact the first electrode E1.

[0119] According to one embodiment of this disclosure, the light-emitting layer EL may include two or more organic light-emitting layers to emit white light. For example, the light-emitting layer EL may include a first organic light-emitting layer and a second organic light-emitting layer to emit white light by mixing a first light and a second light.

[0120] The second electrode E2 is disposed on the light-emitting layer EL and can directly contact the light-emitting layer EL. Compared with the light-emitting layer EL, the second electrode E2 can have a relatively thin thickness.

[0121] According to one embodiment of this disclosure, for top emission, the first electrode E1 may have a structure capable of reflecting light emitted from the light-emitting layer EL and incident on the first electrode E1 toward the opposite side of the substrate 110. To reflect the light emitted from and incident on the light-emitting layer EL toward the opposite side of the substrate 110, the first electrode E1 may include a metallic material with high reflectivity. For example, the first electrode E1 may have a single-layer or multi-layer structure made of one or an alloy of two or more materials selected from aluminum (Al), silver (Ag), molybdenum (Mo), gold (Au), magnesium (Mg), calcium (Ca), or barium (Ba), but embodiments of this disclosure are not limited thereto. The first electrode E1 may be an anode.

[0122] The second electrode E2 can have optical transparency or optical transmission properties. In embodiments of this disclosure, optical transparency may be referred to as optical transmission property. According to one embodiment of this disclosure, the second electrode E2 can have both optical transmission and optical reflection properties. The second electrode E2 can have a multilayer structure, including, for example, a layer made of transparent conductive oxide (TCO) and a layer made of a metal having a low work function, but embodiments of this disclosure are not limited thereto. The second electrode E2 can be a cathode.

[0123] The display device 100 according to one embodiment of the present disclosure may further include a dam layer 170. The dam layer 170 may be disposed at the edge of the first electrode E1 and the planarization layer 130. The dam layer 170 may be made of a transparent or opaque material. For example, the dam layer 170 may be a transparent dam layer or a black dam layer. For example, the dam layer 170 may include black pigment, in which case the dam layer 170 may also serve as a light-blocking member between adjacent sub-pixels SP.

[0124] An encapsulation layer 180 may be formed on the substrate 110 to surround the organic light-emitting element 160. The encapsulation layer 180 may be disposed on the second electrode E2. For example, the encapsulation layer 180 may surround the display area AA. The encapsulation layer 180 may protect the thin-film transistor and the light-emitting layer EL from external impacts and may be used to prevent oxygen, moisture or foreign particles from penetrating into the light-emitting layer EL.

[0125] According to one embodiment of this disclosure, the encapsulation layer 180 may include a plurality of inorganic encapsulation layers. The encapsulation layer 180 may also include at least one organic encapsulation layer interposed between the plurality of inorganic encapsulation layers.

[0126] According to one embodiment of the present disclosure, the display device 100 may further include a color filter layer 150. The color filter layer 150 may be disposed in the direction in which light is emitted from the organic light-emitting element 160. According to one embodiment of the present disclosure, with the organic light-emitting element 160 as the center, the color filter layer 150 may be disposed on the opposite side of the substrate 110.

[0127] The color filter layer 150 may be disposed on the organic light-emitting element 160 so as to overlap with at least one light-emitting region EA. According to one embodiment of the present disclosure, the color filter layer 150 may be disposed on the encapsulation layer 180.

[0128] The color filter layer 150 may have a size wider than the light-emitting region EA. For example, the edge portion of the color filter layer 150 may overlap with the dam layer 170. According to one embodiment of the present disclosure, the color filter layer 150 may have a size corresponding to the entire sub-pixel region SPA of each sub-pixel SP, thereby reducing light leakage between adjacent sub-pixels SP.

[0129] According to one embodiment of this disclosure, the color filter layer 150 can be configured to transmit the wavelength of a color set in the sub-pixel SP. For example, as Figure 3 As shown, when a pixel P includes a first sub-pixel SP1, a second sub-pixel SP2, a third sub-pixel SP3, and a fourth sub-pixel SP4, the color filter layer 150 may include a red color filter disposed in the first sub-pixel SP1, a green color filter disposed in the third sub-pixel SP3, and a blue color filter disposed in the fourth sub-pixel SP4. The second sub-pixel SP2 may not include a color filter layer, or it may include a transparent material for step compensation, thereby emitting white light.

[0130] According to this disclosure, the color filter layer 150 may be formed on the upper surface of the encapsulation layer 180 to overlap with the light-emitting region EA. For example, the color filter layer 150 may contact the upper surface of the encapsulation layer 180. However, embodiments of this disclosure are not limited thereto, and a transparent adhesive member may be disposed between the encapsulation layer 180 and the color filter layer 150.

[0131] According to one embodiment of the present disclosure, the display device 100 may further include a black matrix 155 disposed between color filters in the color filter layer 150.

[0132] The black matrix 155 can be configured to overlap with the remaining area of ​​each sub-pixel SP, excluding the emitting region EA. However, embodiments of this disclosure are not limited thereto; the remaining area of ​​each sub-pixel SP, excluding the emitting region EA, may include a stacked structure of at least two or more color filters instead of the black matrix 155. For example, the remaining area of ​​each sub-pixel SP, excluding the emitting region EA, may include a stacked structure of at least two or more of the red, green, and blue color filters. Instead of the black matrix 155, the stacked structure of at least two or more color filters can prevent color mixing between adjacent sub-pixels SP.

[0133] refer to Figure 4An outer coating 185 may be applied to the color filter layer 150. The outer coating 185 protects the color filter layer 150 and flattens the upper part of the color filter layer 150. The outer coating 185 may also be referred to as a protective layer. The outer coating 185 may also be omitted.

[0134] According to one embodiment of this disclosure, the stack from substrate 110 to color filter layer 150 is referred to as display panel 310. (See also...) Figure 4 The stack from substrate 110 to outer coating 185 can also be referred to as display panel 310.

[0135] A display device 100 according to one embodiment of the present disclosure includes an optical enhancement layer 210 disposed on a display panel 310. A first adhesive member 190 may be disposed between the display panel 310 and the optical enhancement layer 210. The optical enhancement layer 210 may be attached and fixed to the display panel 310 by means of the first adhesive member 190.

[0136] refer to Figure 4 The display device 100 may include a cover substrate 250. An optical enhancement layer 210 may be disposed between the display panel 310 and the cover substrate 250. Additionally, a second adhesive member 290 may be disposed between the optical enhancement layer 210 and the cover substrate 250. The optical enhancement layer 210 can be attached and fixed to the cover substrate 250 via the second adhesive member 290.

[0137] The cover substrate 250 can be a glass substrate or a transparent plastic substrate. Light generated from the organic light-emitting element 160 of the display panel 310 can be emitted to the outside through the cover substrate 250. In addition, external light can be incident through the cover substrate 250, and external light can be reflected by the cover substrate 250.

[0138] When external light is reflected from the cover substrate 250, glare occurs on the cover substrate 250, and the reflected image can be seen by the user. To prevent this glare phenomenon and the seeing of the reflected image, the cover substrate 250 can be subjected to an anti-glare treatment or a matte treatment. The anti-glare treatment or matte treatment for the cover substrate 250 may include, for example, forming a fine pattern or performing a roughening treatment on the cover substrate 250.

[0139] The fine or rough pattern formed on the cover substrate 250 is a random pattern. However, due to the irregularity or non-uniformity of the multiple randomly arranged patterns, flickering or sand-like phenomena may occur.

[0140] Flickering refers to the phenomenon where bright and dark areas are irregularly perceived as spots on the display surface at locations corresponding to intervals between patterns. This flickering phenomenon is particularly noticeable in the display device 100, which includes self-emissive light-emitting elements. For example, in the display panel 310, which includes an organic light-emitting element 160 as a self-emissive display element, when light generated from the organic light-emitting element 160 is emitted to the outside through the display panel 310 and the cover substrate 250, bright and dark areas can be irregularly perceived as tiny bubbles on the display surface at locations corresponding to intervals between multiple randomly arranged patterns. This phenomenon, where tiny bubble-like shapes are irregularly perceived, is called flickering.

[0141] Meanwhile, the display device 100 has a multi-layered structure with various functions. When light is incident from the outside of the display device 100 (external light incident), reflection and refraction occur in the layers constituting the cover substrate 250 and the display panel 310. Due to fluctuations in the reflected or refracted light under various conditions, a blurry area, as if sand has been sprinkled on that area, may be perceived in the region near the point where the reflected external light is detected. In this way, the phenomenon of perceiving a blurry area near the point where the reflected external light is detected is called the sand phenomenon.

[0142] In order to prevent or suppress flickering or graininess in the display device 100, according to one embodiment of the present disclosure, an optical improvement layer 210 is disposed on the display panel 310.

[0143] Figure 5 yes Figure 4 A partial cross-sectional view of the optical improvement layer 210.

[0144] The optical enhancement layer 210 includes a first patterned layer 211 and a second patterned layer 212. The first patterned layer 211 and the second patterned layer 212 overlap each other. The first patterned layer 211 has a first refractive index, and the second patterned layer 212 has a second refractive index different from the first refractive index.

[0145] The first pattern layer 211 and the second pattern layer 212 can each be made of light-transmitting resin. Light-transmitting resin can also be called transparent resin.

[0146] According to one embodiment of this disclosure, a translucent resin can be formed by polymerizing monomers. For monomer polymerization, light can be applied (photopolymerization) or heat can be applied (thermal polymerization). For example, UV light can be used for photopolymerization.

[0147] Furthermore, to form a translucent resin, curing can be performed after monomer polymerization. Curing methods include photocuring and thermal curing. According to one embodiment of this disclosure, a translucent resin can be formed by UV photocuring using UV light.

[0148] The light-transmitting resin may include at least one of polymethyl methacrylate (PMMA) based, polycarbonate (PC) based, polyethylene terephthalate (PET) based, polyurethane (PU) based, and polystyrene (PS) based polymer resins.

[0149] The first pattern layer 211 and the second pattern layer 212 can be made of materials from the same or different series. Even if the first pattern layer 211 and the second pattern layer 212 are made of materials from the same series, they can have different refractive indices when the curing conditions are different.

[0150] The first patterned layer 211 and the second patterned layer 212 can each independently have a refractive index in, for example, the range of 1.4 to 2.0. The refractive indices of the first patterned layer 211 and the second patterned layer 212 can be adjusted independently depending on the type of material forming the light-transmitting resin and the curing conditions.

[0151] Reference Figure 4 An intermediate layer 214 may be disposed on the first pattern layer 211. The intermediate layer 214 may have a different refractive index than the first pattern layer 211. Due to the refractive index difference between the first pattern layer 211 and the intermediate layer 214, light can be refracted at the interface between the first pattern layer 211 and the intermediate layer 214.

[0152] Reference Figure 4 A fill layer 213 can be disposed on the second pattern layer 212. The upper part of the second pattern layer 212 can be planarized by the fill layer 213. The fill layer 213 can be placed between the patterns HP contained in the second pattern layer 212.

[0153] The filler layer 213 and the intermediate layer 214 may each be made of a light-transmitting resin. The light-transmitting resin may include at least one of polymethyl methacrylate (PMMA) based, polycarbonate (PC) based, polyethylene terephthalate (PET) based, polyurethane (PU) based, and polystyrene (PS) based polymer resins.

[0154] The filler layer 213 and the intermediate layer 214 can each independently have a refractive index in the range of, for example, 1.4 to 2.0. The refractive indexes of the filler layer 213 and the intermediate layer 214 can be adjusted independently depending on the type of material forming the light-transmitting resin and the curing conditions.

[0155] According to one embodiment of this disclosure, such as Figure 4 and Figure 5As shown, the first pattern layer 211 may have multiple lens patterns LS. More specifically, the first pattern layer 211 may include multiple patterns having a lens shape. Hereinafter, the pattern having a lens shape is referred to as the lens pattern LS. In embodiments of this disclosure, the multiple lens patterns LS may have one or more vertices. The one or more vertices may be arc-shaped or curved. In this respect, when viewed in a cross-sectional view, the multiple lens patterns LS may have curved or convex profiles.

[0156] The multiple lens patterns LS contained in the first pattern layer 211 can each have different sizes. The first pattern layer 211 can be formed by arranging multiple lens patterns LS with non-uniform sizes on a single plane.

[0157] The first pattern layer 211 may have an average pattern size of 20 μm to 50 μm. The average pattern size may be referred to as the average size of the multiple lens patterns LS contained in the first pattern layer 211.

[0158] According to one embodiment of this disclosure, in a planar image of the first pattern layer 211, the maximum diameter of each of a plurality of patterns is measured, and the average value of these maximum diameters is calculated. This average value can be referred to as the average pattern size. Therefore, the average pattern size can be referred to as the average of the maximum diameters of the plurality of patterns in the planar image of the first pattern layer 211.

[0159] Figure 6A This is a plan view of the first pattern layer 211. Figure 6A In this context, each lens pattern LS can be defined by the boundaries of the pattern. Furthermore, as... Figure 6A As shown, the maximum diameter 'a' of each of the multiple patterns can be referred to as the maximum length of each lens pattern LS displayed in the plane.

[0160] The average pattern size of the first pattern layer 211 can be the average size of the multiple lens patterns LS contained in the first pattern layer 211. When the first pattern layer 211 has an average pattern size of 20 μm to 50 μm, the Mura visibility phenomenon caused by external light can be effectively prevented or suppressed.

[0161] When external light is incident on the display device 10 and reflected, coherence may occur due to diffraction by the elements constituting the display device 100, and rainbow patterns or ring patterns may appear due to coherence. Such patterns are called Mura. Mura can also be referred to as reflection diffraction Mura, rainbow Mura, etc. According to one embodiment of this disclosure, Mura can be prevented or suppressed by a first pattern layer 211 comprising a plurality of lens patterns LS with an average pattern size of 20 μm to 50 μm.

[0162] In detail, the first pattern layer 211 can have an average pattern size of 30 μm to 40 μm, or an average pattern size of about 35 μm.

[0163] According to one embodiment of this disclosure, the first patterned layer 211 may have an arithmetic mean roughness (Ra) of 1.7 μm to 3.7 μm. The arithmetic mean roughness (Ra) can be measured using a surface roughness measuring device according to JIS (Japanese Industrial Standard) B0601.

[0164] In detail, the first pattern layer 211 may have an arithmetic mean roughness (Ra) in the range of 2.0 μm to 3.5 μm, an arithmetic mean roughness (Ra) in the range of 2.5 μm to 3.0 μm, and an arithmetic mean roughness (Ra) of about 2.7 μm.

[0165] Additionally, the first pattern layer 211 can have an average width (Rsm) of 130 μm to 170 μm. The average width (Rsm) can be defined as the average distance of the profile elements within the sampling length. The average width (Rsm) can be measured using a surface roughness measuring device according to the JIS B0601 standard. Since the average width (Rsm) is the average width within the sampling length, it may differ from the size of a single pattern.

[0166] In detail, the first pattern layer 211 may have an average width (Rsm) of 140 μm to 160 μm, an average width (Rsm) of 145 μm to 155 μm, or an average width (Rsm) in the range of 150 μm to 153 μm.

[0167] According to one embodiment of the present disclosure, a first pattern layer 211 having an average pattern size of 20 μm to 50 μm, an arithmetic mean roughness (Ra) of 1.7 μm to 3.7 μm, and an average width (Rsm) of 130 μm to 170 μm is used in a manner that overlaps with the second pattern layer 212, thereby preventing flickering and graininess in the display device 100.

[0168] According to one embodiment of the present disclosure, the second pattern layer 212 may be disposed on the first pattern layer 211.

[0169] The second pattern layer 212 may include a plurality of patterns HP having horn-shaped shapes. The patterns HP included in the second pattern layer 212 may have sharp, protruding shapes. In embodiments of this disclosure, the plurality of patterns HP may have one or more vertices. The one or more vertices may be sharp or pointed. In this respect, when viewed in a cross-sectional view, the plurality of patterns HP may have jagged and / or irregular contours.

[0170] The multiple patterns HP contained in the second pattern layer 212 can each have different sizes. The second pattern layer 212 can be formed by arranging multiple angular patterns HP with non-uniform sizes on a single plane.

[0171] According to one embodiment of the present disclosure, the average pattern size of the second pattern layer 212 is smaller than the average pattern size of the first pattern layer 211.

[0172] The second pattern layer 212 may have an average pattern size of, for example, 2 μm to 5 μm. The average pattern size of the second pattern layer 212 may be defined as the average of the maximum diameters of the multiple patterns HP in the planar image of the second pattern layer 212.

[0173] Figure 6B This is a plan view of the second pattern layer 212. Figure 6B In this context, each angular pattern HP can be defined by the boundary of the pattern. Furthermore, as... Figure 6B As shown, the maximum diameter 'a' of each of the multiple patterns can be said to be the maximum length of each pattern HP displayed in the plane.

[0174] In detail, the second pattern layer 212 can have an average pattern size of 3 μm to 4 μm, or an average pattern size of about 3.5 μm.

[0175] According to one embodiment of this disclosure, the second patterned layer 212 may have an arithmetic mean roughness (Ra) of 0.4 μm to 0.7 μm. The arithmetic mean roughness (Ra) can be measured using a surface roughness measuring device according to JIS (Japanese Industrial Standard) B0601.

[0176] In detail, the second pattern layer 212 may have an arithmetic mean roughness (Ra) in the range of 0.5 μm to 0.6 μm, or an arithmetic mean roughness (Ra) of about 0.53 μm.

[0177] According to one embodiment of this disclosure, the second patterned layer 212 may have an average width (Rsm) of 60 μm to 100 μm. The average width (Rsm) can be measured using a surface roughness measuring device according to the JIS B0601 standard.

[0178] In detail, the second pattern layer 212 may have an average width (Rsm) of 70 μm to 90 μm, an average width (Rsm) of 75 μm to 85 μm, or an average width (Rsm) of about 80 μm.

[0179] Furthermore, the average pattern ratio of the patterns contained in the first pattern layer 211 is less than the average pattern ratio of the patterns contained in the second pattern layer 212.

[0180] Here, as described above, the average pattern size is the average of the maximum diameters of the plurality of patterns in the respective planar images of the first pattern layer 211 and the second pattern layer 212. Furthermore, when the maximum diameter of each pattern is *a* and the height is *b*, the pattern ratio is calculated as *b / a*. The average pattern ratio is calculated as the average of the pattern ratios of the plurality of patterns. In various embodiments of this disclosure, the pattern ratio *b / a* of the first pattern layer 211 may be less than or equal to 1.0, where *b* is less than or equal to *a*; however, embodiments of this disclosure are not limited to this, and the pattern ratio *b / a* of the first pattern layer may also be greater than 1.0, where *b* is greater than *a*. Furthermore, in various embodiments of this disclosure, the pattern ratio *b / a* of the second pattern layer 212 may be greater than or equal to 1.0, where *b* is greater than or equal to *a*; however, embodiments of this disclosure are not limited to this, and the pattern ratio *b / a* of the second pattern layer may also be less than 1.0, where *b* is less than *a*.

[0181] According to one embodiment of the present disclosure, when the first pattern layer 211 and the second pattern layer 212 are stacked in an overlapping manner, the first pattern layer 211 has a larger average pattern size than the second pattern layer 212, and the average pattern ratio of the patterns contained in the first pattern layer 211 is less than the average pattern ratio of the patterns contained in the second pattern layer 212, which can prevent or suppress flickering and graininess in the display device 100.

[0182] For example, refer to Figure 5 , Figure 6A and Figure 6B The heights of the plurality of patterns HP included in the second pattern layer 212 can typically vary or be irregular. Thus, when variations exist, the height of some patterns HP is approximately 0.5 times to approximately 5 times greater than the height of other patterns HP. Furthermore, the diameters of the plurality of patterns HP included in the second pattern layer 212 can typically vary in size or dimensions. Thus, when variations exist, the diameter of some patterns HP is approximately 0.5 times to approximately 5 times greater than the diameter of other patterns HP. However, embodiments of this disclosure are not limited to this.

[0183] Furthermore, the heights of the plurality of lens patterns LS included in the first pattern layer 211 can generally be similar to or regular to each other, so that the height of some lens patterns in the plurality of lens patterns LS is the same as or similar to the height of other lens patterns in the plurality of lens patterns LS, or when there is a variation, the variation is about 0.4 times or less. Furthermore, the diameters of the plurality of lens patterns LS included in the first pattern layer 211 can be similar or the same, so that when there is a variation, the diameter of some lens patterns in the plurality of lens patterns LS is about 0.4 times or less larger than the diameter of other lens patterns in the plurality of lens patterns LS, but the embodiments of this disclosure are not limited thereto.

[0184] Further reference Figure 6A In the first pattern layer 211, the plurality of lens patterns LS can be in contact with each other at their bottoms in a planar view and form a polygon. In various embodiments of this disclosure, the bottoms of the plurality of lens patterns LS can be formed into a hexagonal pattern. Furthermore, referring to… Figure 6B The multiple patterns HP included in the second pattern layer 212 can contact each other in the planar view and form a gap-filling pattern, wherein the multiple patterns HP with relatively small diameters are gap-filled between the multiple patterns HP with relatively large diameters.

[0185] In addition, refer to Figure 5 , Figure 6A and Figure 6B Each of the multiple lens patterns LS has a vertex corresponding to height b, and each of the multiple patterns HP has a vertex corresponding to height b. When the multiple lens patterns LS are arranged to overlap with the multiple patterns HP, each lens pattern LS overlaps with the multiple patterns HP. For example, multiple vertices of the multiple patterns HP correspond to vertices of the lens pattern LS.

[0186] Figure 7A and Figure 7B This is a schematic diagram explaining the mechanism for eliminating flickering. In Figure 7A and Figure 7B In the waveform diagram shown on the right, the horizontal direction represents the X direction of the display device 100, and the vertical direction represents the light intensity.

[0187] like Figure 7A As shown, when the display device 100 is in the ON state, the organic light-emitting element 160 included in the display panel 310 is driven and the organic light-emitting element 160 emits light.

[0188] During the emission of light generated from the organic light-emitting element 160 to the outside, the light passes through various layers included in the display panel 310. The light passing through the display panel 310 passes through the optical enhancement layer 210. Since the optical enhancement layer 210 includes irregular patterns disposed in the first pattern layer 211 and the second pattern layer 212, the light passing through the optical enhancement layer 210 can have characteristics such as… Figure 7A The waveform of Wave1.

[0189] Meanwhile, the cover substrate 250 is a flat substrate, and when parallel light passes through the cover substrate 250, the light can have a waveform such as Wave2. Therefore, when light passing through the optical improvement layer 210 passes through the cover substrate 250, the light after passing through the cover substrate 250 can have a waveform as... Figure 7A The waveform of the combination of Wave1 and Wave2.

[0190] like Figure 7B As shown, when Wave1 and Wave2 are combined, destructive interference occurs, and the emission exhibits the following characteristics: Figure 7B The lower part shows the waveform of the light. (Example:) Figure 7B As shown, the emitted light, after passing through the optical enhancement layer 210 and the cover substrate 250, exhibits a small deviation in light intensity depending on the location. Therefore, the pattern may be invisible to the user. In this way, flickering can be eliminated or reduced when using the optical enhancement layer 210 according to an embodiment of this disclosure.

[0191] Figure 8A and Figure 8B This is a schematic diagram explaining the mechanism for eliminating sand particles.

[0192] like Figure 8A As shown, when the display device 100 is in the OFF state, the reflected light caused by external light is clearly visible to the user.

[0193] Light incident on the display device 100 can be reflected by the optical improvement layer 210. Since the light passes through the irregular patterns provided in the first pattern layer 211 and the second pattern layer 212, the light reflected by the optical improvement layer 210 can have properties such as… Figure 8A The waveform of Wave3.

[0194] Additionally, external light can be reflected from the cover substrate 250. The light reflected from the cover substrate 250 can have characteristics such as... Figure 8A The waveform of Wave4.

[0195] The user sees light reflected from the optical improvement layer 210 and light reflected from the cover substrate 250. Therefore, the light seen by the user can have the following characteristics: Figure 8A The waveform of the combination of Wave3 and Wave4.

[0196] like Figure 8B As shown, when Wave3 and Wave4 are combined, destructive interference occurs, and the user observes an effect similar to... Figure 8B The lower part shows the waveform of the light. (Example:) Figure 8B As shown, the light seen by the user has a small deviation in light intensity depending on the location. Therefore, the pattern may be invisible to the user. In this way, when using the optical improvement layer 210 according to an embodiment of this disclosure, the sand-like phenomenon can be eliminated or reduced.

[0197] Refraction occurs in the optical improvement layer 210 to eliminate or reduce flickering and grittiness. Specifically, light refraction occurs at the interface between the first pattern layer 211 and the intermediate layer 214, and at the interface between the second pattern layer 212 and the fill layer 213.

[0198] According to one embodiment of this disclosure, such as Figure 4 and Figure 5 As shown, the intermediate layer 214 can contact the first patterned layer 211. Furthermore, the first patterned layer 211 and the intermediate layer 214 can have a refractive index difference of 0.05 to 0.1. Due to this refractive index difference, light refraction can occur between the first patterned layer 211 and the intermediate layer 214.

[0199] When the refractive index difference between the first patterned layer 211 and the intermediate layer 214 is less than 0.05, significant refraction may not occur at the boundary between the first patterned layer 211 and the intermediate layer 214. Furthermore, when the refractive index difference between the first patterned layer 211 and the intermediate layer 214 exceeds 0.1, light generated from the organic light-emitting element 160 may be difficult to emit to the outside due to excessive refraction, and light loss due to total internal reflection may occur. Therefore, according to one embodiment of this disclosure, the refractive index difference between the first patterned layer 211 and the intermediate layer 214 can be adjusted to a range of 0.05 to 0.1.

[0200] According to one embodiment of this disclosure, such as Figure 4 and Figure 5 As shown, the filler layer 213 can contact the second pattern layer 212. Furthermore, the second pattern layer 212 and the filler layer 213 can have a refractive index difference of 0.05 to 0.1. Due to this refractive index difference, light refraction can occur between the second pattern layer 212 and the filler layer 213.

[0201] When the refractive index difference between the second patterned layer 212 and the filling layer 213 is less than 0.05, significant refraction may not occur at the interface between the second patterned layer 212 and the filling layer 213. Furthermore, when the refractive index difference between the second patterned layer 212 and the filling layer 213 exceeds 0.1, light generated from the organic light-emitting element 160 may be difficult to emit to the outside due to excessive refraction, and light loss due to total internal reflection may occur. Therefore, according to one embodiment of this disclosure, the refractive index difference between the second patterned layer 212 and the filling layer 213 can be adjusted to a range of 0.05 to 0.1.

[0202] According to one embodiment of the present disclosure, the intermediate layer 214 may contact the first pattern layer 211 and the second pattern layer 212.

[0203] According to one embodiment of this disclosure, the light extraction efficiency of the display device 100 can be improved by allowing light to pass directly through the intermediate layer 214 and the second pattern layer 212 without refraction. For this purpose, the refractive index difference between the intermediate layer 214 and the second pattern layer 212 can be adjusted to 0.01 or less. When the refractive index difference between the intermediate layer 214 and the second pattern layer 212 is 0.01 or less, light passing through the intermediate layer 214 can be incident on the second pattern layer 212 without refraction.

[0204] In detail, the intermediate layer 214 may have the same refractive index as the second patterned layer 212. Furthermore, the intermediate layer 214 may be made of the same material as the second patterned layer 212.

[0205] The refractive indices of the first pattern layer 211, the second pattern layer 212, the filler layer 213, and the intermediate layer 214 can vary depending on the materials used, curing conditions, etc., and the refractive index of each layer can be adjusted independently.

[0206] According to one embodiment of this disclosure, the refractive index difference between the first patterned layer 211 and the intermediate layer 214 can be equal to the refractive index difference between the second patterned layer 212 and the filler layer 213. In this case, the number of variables related to refractive index can be reduced, thereby facilitating the design of the display device 100.

[0207] The filler layer 213 may have the same refractive index as the cover substrate 250. Furthermore, the second adhesive member 290 between the filler layer 213 and the cover substrate 250 may also have the same refractive index as both the filler layer 213 and the cover substrate 250. In this case, when light generated from the organic light-emitting element 160 passes through the filler layer 213, the second adhesive member 290, and the cover substrate 250 and is emitted to the outside, unnecessary light loss due to interface reflection can be prevented or reduced.

[0208] refer to Figure 4The display panel 310 includes an outer coating layer 185, and a first pattern layer 211 may be disposed on the outer coating layer 185. The outer coating layer 185 may have the same refractive index as the first pattern layer 211. Furthermore, the first adhesive member 190 between the outer coating layer 185 and the first pattern layer 211 may also have the same refractive index as the outer coating layer 185 and the first pattern layer 211. In this case, unwanted light loss due to interface reflection can be prevented or suppressed when light generated from the organic light-emitting element 160 passes through the color filter layer 150, the outer coating layer 185, the first adhesive member 190, and the first pattern layer 211.

[0209] Figure 9 This is a partial cross-sectional view of a display device 200 according to another embodiment of the present disclosure. In the following text, descriptions of already described components are omitted to avoid repetition.

[0210] Reference Figure 9 The intermediate layer 214 and the second patterned layer 212 can be integrally formed. For example, the intermediate layer 214 can be formed on the first patterned layer 211, and the upper surface of the intermediate layer 214 can be patterned so that the upper part of the intermediate layer 214 becomes the second patterned layer 212, thereby integrally forming the intermediate layer 214 and the second patterned layer 212.

[0211] Since the intermediate layer 214 and the second pattern layer 212 are formed as one unit, light loss between the intermediate layer 214 and the second pattern layer 212 can be minimized or prevented.

[0212] Furthermore, the first patterned layer 211 and the second patterned layer 212 may have a refractive index difference of 0.05 to 0.1. Because the first patterned layer 211 and the second patterned layer 212 have a refractive index difference, light refraction can occur at the interface between the first patterned layer 211 and the second patterned layer 212.

[0213] Furthermore, the second patterned layer 212 and the filling layer 213 may have a refractive index difference of 0.05 to 0.1. Because the second patterned layer 212 and the filling layer 213 have a refractive index difference, light refraction can occur at the interface between the second patterned layer 212 and the filling layer 213.

[0214] According to one embodiment of this disclosure, the first patterned layer 211 and the filler layer 213 can be made of the same material. Furthermore, the first patterned layer 211 and the filler layer 213 can have the same refractive index. Because... Figure 9In the display device 200, the intermediate layer 214 and the second patterned layer 212 are integrally formed. If the first patterned layer 211 and the filler layer 213 have the same refractive index, the refractive index difference between the first patterned layer 211 and the intermediate layer 214 can be the same as the refractive index difference between the second patterned layer 212 and the filler layer 213. When the refractive index difference between the first patterned layer 211 and the intermediate layer 214 is the same as the refractive index difference between the second patterned layer 212 and the filler layer 213, the number of variables related to refractive index can be reduced, and the selection of materials can be simplified, thereby facilitating the manufacturing and design of the display device 200.

[0215] Figures 10 to 16 These are partial cross-sectional views of an optical improvement layer 210 applied to a display device according to another embodiment of the present disclosure.

[0216] Reference Figure 10 In the optical improvement layer 210 of the display device 300 according to another embodiment of the present disclosure, a filling layer 213 and an intermediate layer 214 may be disposed between a first pattern layer 211 and a second pattern layer 212. The filling layer 213 and the intermediate layer 214 may be in contact with each other.

[0217] In detail, the intermediate layer 214 can contact the first pattern layer 211 and the fill layer 213, and the fill layer 213 can contact the second pattern layer 212 and the intermediate layer 214.

[0218] Figure 10 The optical enhancement layer 210 shown has protrusions corresponding to the first pattern layer 211 and the second pattern layer 212 arranged to face each other. In this case, the first pattern layer 211 and the second pattern layer 212 can be spaced as far apart as possible from each other.

[0219] refer to Figure 10 The filler layer 213 and the intermediate layer 214 can have the same refractive index. In this case, unnecessary light refraction at the interface between the filler layer 213 and the intermediate layer 214 can be prevented, thereby improving the light extraction efficiency of the display device 300. According to another embodiment of this disclosure, the filler layer 213 and the intermediate layer 214 can be formed of the same material.

[0220] Furthermore, the first patterned layer 211 and the second patterned layer 212 can have the same refractive index. Specifically, the first patterned layer 211 and the second patterned layer 212 can be made of the same material.

[0221] Figure 11 An optical improvement layer 210 of a display device 400 according to another embodiment of the present disclosure is shown. Reference Figure 11 The filler layer 213 and the intermediate layer 214 can be formed integrally. Figure 11The structure can also be described as a structure in which the first pattern layer 211 and the second pattern layer 212 are formed from the same material.

[0222] according to Figure 11 The structure, since there is no interface between the filling layer 213 and the intermediate layer 214, prevents unnecessary light refraction, thereby improving the light extraction efficiency of the display device 400.

[0223] exist Figure 11 In the optical improvement layer 210 shown, the refractive index difference between the first pattern layer 211 and the intermediate layer 214 can be the same as the refractive index difference between the second pattern layer 212 and the filling layer 213.

[0224] Figure 12 An optical improvement layer 210 of a display device 500 according to another embodiment of the present disclosure is shown. (See also...) Figure 12 The fill layer 213 can be disposed between the first pattern layer 211 and the second pattern layer 212. Figure 12 The optical enhancement layer 210 shown can be said to have a structure in which a first pattern layer 211 is disposed on a second pattern layer 212.

[0225] refer to Figure 12 A first sheet is formed, comprising a first pattern layer 211 and an intermediate layer 214; a second sheet is formed, comprising a second pattern layer 212 and a filler layer 213; and then the first sheet is attached to the second sheet, thereby forming a... Figure 12 The optical improvement layer 210 is shown.

[0226] when Figure 12 When the optical improvement layer 210 is disposed on the display panel 310, the intermediate layer 214 can contact the display panel 310. At this time, without the first adhesive member 190, the intermediate layer 214 of the optical improvement layer 210 is directly bonded to the display panel 310, thereby reducing the distance between the display panel 310 and the first pattern layer 211 and the second pattern layer 212.

[0227] At this point, in order to bond the optical improvement layer 210, the intermediate layer 214 can be made of an adhesive material.

[0228] Figure 13 An optical enhancement layer 210 of a display device 600 according to another embodiment of the present disclosure is shown. Figure 13 The structure shown corresponds to Figure 12 The structure of the optical enhancement layer 210 shown is such that the filling layer 213 and the first patterning layer 211 are integrally formed. (Refer to...) Figure 13 The filler layer 213 and the first pattern layer 211 can be made of the same material.

[0229] In this configuration, the first patterned layer 211 and the second patterned layer 212 can have a refractive index difference of 0.05 to 0.1. Significant light refraction can occur at the interface between the first patterned layer 211 and the second patterned layer 212 under these conditions.

[0230] Figure 14 An optical improvement layer 210 of a display device 700 according to another embodiment of the present disclosure is shown. (See also...) Figure 14 The first pattern layer 211 and the second pattern layer 212 can be in contact with each other. At this time, the protrusions of the first pattern layer 211 and the protrusions of the second pattern layer 212 can protrude in opposite directions.

[0231] Reference Figure 14 A first sheet comprising a first pattern layer 211 and an intermediate layer 214 is formed, and a second sheet comprising a second pattern layer 212 and a filler layer 213 is formed. The first and second sheets are then attached to form a structure as shown in the diagram. Figure 14 The optical enhancement layer 210 is shown. At this time, the first sheet and the second sheet can be attached such that the first pattern layer 211 and the second pattern layer 212 adhere to each other.

[0232] when Figure 14 When the optical enhancement layer 210 is disposed on the display panel 310, the intermediate layer 214 can contact the display panel 310. At this time, without the first adhesive member 190, the intermediate layer 214 of the optical enhancement layer 210 can be directly bonded to the display panel 310. For this purpose, the intermediate layer 214 can be made of an adhesive material.

[0233] Figure 15 An optical improvement layer 210 of a display device 800 according to another embodiment of the present disclosure is shown. Figure 15 The structure shown corresponds to Figure 14 The optical enhancement layer 210 shown has a structure in which the first pattern layer 211 and the second pattern layer 212 are integrally formed. In this case, the first pattern layer 211 and the second pattern layer 212 can be made of the same material.

[0234] Figure 16 An optical enhancement layer 210 is shown in a display device 900 according to another embodiment of the present disclosure. Figure 16 The optical enhancement layer 210 shown may also include a spacer 219. The spacer 219 may be disposed between the intermediate layer 214 and the filler layer 213.

[0235] Figure 16 The optical improvement layer 210 shown is as follows: Figure 10The first pattern layer 211, intermediate layer 214, filling layer 213 and second pattern layer 212 shown have the same structure arranged in sequence, and the spacer 219 is disposed between the intermediate layer 214 and the filling layer 213.

[0236] The thickness of the optical improvement layer 210 can be controlled by the spacer 219, and the distance between the first pattern layer 211 and the second pattern layer 212 can be controlled.

[0237] refer to Figures 9 to 16 The vertices of the plurality of lens patterns LS included in the first pattern layer 211 and the vertices of the plurality of patterns HP included in the second pattern layer 212 can point in various directions relative to the display panel 310. For example, as Figure 9 , Figure 12 and Figure 13 As shown, the vertices of multiple lens patterns LS and multiple patterns HP can point in the same direction. When the vertices of multiple lens patterns LS and multiple patterns HP point in the same direction, the vertices can be as follows: Figure 9 The direction shown points away from the display panel 310, or it can be as follows: Figure 12 and Figure 13 The image points to the front of the display panel.

[0238] In addition, such as Figure 10 , Figure 11 , Figure 14 , Figure 15 and Figure 16 As shown, the vertices of multiple lens patterns LS and multiple patterns HP can point in different directions. When the vertices of multiple lens patterns LS and multiple patterns HP point in different directions, the vertices can be as follows: Figure 10 , Figure 11 and Figure 16 As shown, they face each other, or they can be like... Figure 14 and Figure 15 As shown, they are facing away from each other. When the vertices of the multiple lens patterns LS and the multiple patterns HP point in different directions, one of the vertices of the multiple lens patterns LS and the multiple patterns HP can face the display panel 310, while the other faces away from the display panel.

[0239] Below, with reference to comparative examples, we will explain the elimination and reduction of flickering and sand-like phenomena.

[0240] Figure 17A This is a partial cross-sectional view of the display device based on Comparative Example 1. Figure 17B This is a partial cross-sectional view of the display device based on Comparative Example 2.

[0241] Figure 17A The display device shown (Comparative Example 1) does not include the optical improvement layer 210 according to the embodiments of the present disclosure. Figure 17A The display device shown (Comparative Example 1) includes a display panel 310, a second adhesive member 290 on the display panel 310, and a cover substrate 250 on the second adhesive member 290.

[0242] Figure 17B The display device shown (Comparative Example 2) does not include the optical improvement layer 210 according to an embodiment of the present disclosure, but includes a lens layer 280. The lens layer 280 includes a first pattern layer 211 and an intermediate layer 214. In detail, Figure 17B The display device shown (Comparative Example 2) includes a display panel 310, a first adhesive member 190 on the display panel 310, a lens layer 280 on the first adhesive member 190, a second adhesive member 290 on the lens layer 280, and a cover substrate 250 on the second adhesive member 290.

[0243] Figure 18 The image shows the elimination of flickering and sand-like phenomena.

[0244] exist Figure 18 The image shown as "internal light" is a photograph of the display surface of the display device taken when the display device is turned on and light is emitted from inside the display device.

[0245] exist Figure 18 The image shown as "external light" is a photograph of the light reflected when the display device is off and a point light source is illuminating the display device.

[0246] When internal light is emitted from the display devices of Comparative Example 1 and Comparative Example 2, it can be confirmed that flickering, such as tiny bubbles, is produced.

[0247] Furthermore, when the display device is in the off state and external light (illumination) is shone on the display devices of Comparative Example 1 and Comparative Example 2, it can be confirmed that a blurry sand-like phenomenon occurs, as if sand has been scattered around the location where the external light is reflected.

[0248] On the other hand, it can be confirmed that in the display device according to Embodiment 1, no flickering occurs and no sand-like phenomenon occurs.

[0249] Another embodiment of this disclosure provides an optical enhancement layer 210. The optical enhancement layer 210 can be formed as a film or sheet. The optical enhancement layer 210 can be attached to and used in a display panel 310. Since it has already been... Figure 5 as well as Figures 9 to 16 The detailed construction of the optical improvement layer 210 is described in the previous section, so a detailed description of the construction of the optical improvement layer 210 is omitted to avoid repetition.

[0250] In the following, with reference to manufacturing process diagrams, a method for manufacturing an optical enhancement layer 210 according to one embodiment of the present disclosure will be described.

[0251] Figures 19A to 19H This is a schematic cross-sectional view illustrating a method for manufacturing an optical enhancement layer according to one embodiment of the present disclosure.

[0252] Reference Figure 19A A first light-transmitting resin layer 211m is formed on the carrier substrate 450. A glass substrate or a plastic substrate in the form of a film can be used as the carrier substrate 450.

[0253] Reference Figure 19B The first light-transmitting resin layer 211m is patterned using the first roller 410. Patterning can be achieved by forming a negative pattern on the first light-transmitting resin layer 211m using the first roller 410.

[0254] Reference Figure 19C The first pattern layer 211 is formed by patterning using the first roller 410.

[0255] Reference Figure 19D An intermediate layer 214 is formed on the first pattern layer 211. The intermediate layer 214 may be made of a light-transmitting resin.

[0256] Reference Figure 19E A second light-transmitting resin layer 212m is formed on the intermediate layer 214.

[0257] Reference Figure 19F The second translucent resin layer 212m is patterned using the second roller 420. Patterning can be achieved by forming an engraved pattern on the second translucent resin layer 212m using the second roller 420.

[0258] Reference Figure 19G The second pattern layer 212 is formed by patterning using the second roller 420.

[0259] Reference Figure 19H A filler layer 213 is formed on the second pattern layer 212. The filler layer 213 may be made of a light-transmitting resin.

[0260] As a result, the following can be produced: Figure 19H The optical enhancement layer 210 is shown. After the optical enhancement layer 210 is formed, the carrier substrate 450 is removed.

[0261] Figures 20A to 20C This is a schematic perspective view showing a method for manufacturing a first roller 410, which is used to form a first pattern layer 211.

[0262] refer to Figure 20A The first core 411 is manufactured to manufacture the first roll 410.

[0263] Reference Figure 20B A plating layer 412 is formed on the rotating portion of the first core 411. The plating layer 421 may include a copper (Cu) plating layer and a nickel (Ni) plating layer.

[0264] refer to Figure 20C The coating 412 is subjected to laser treatment. The laser generating device 415 is used for laser treatment.

[0265] A hemispherical recess corresponding to the lens pattern is formed in the coating 412 by laser processing. As a result, the first roll 410 can be produced.

[0266] According to one embodiment of this disclosure, the size of the hemispherical recess formed in the coating 412 of the first roller 410 is not constant, but random.

[0267] Figures 21A to 21C This is a schematic perspective view showing a method for manufacturing a second roller 420, which is used to form a second pattern layer 212.

[0268] refer to Figure 21A The second core 421 is manufactured to manufacture the second roll 420.

[0269] Reference Figure 21B A plating layer 422 is formed on the rotating portion of the second core 421. The plating layer 422 may include a copper (Cu) plating layer and a nickel (Ni) plating layer.

[0270] refer to Figure 21C The coating 422 is then sandblasted. A sandblasting machine 425 can be used for sandblasting. High-strength fine particles 426 (e.g., corundum) are atomized onto the coating 422 using the sandblasting machine 425.

[0271] A recess corresponding to the angular shape is formed in the coating 422 by sandblasting. Therefore, a second roll 420 can be produced.

[0272] According to one embodiment of this disclosure, the size of the angular recesses formed in the coating 422 of the second roller 420 is not constant, but random.

[0273] As described above, this disclosure is not limited to the above embodiments and drawings, and it will be apparent to those skilled in the art that various substitutions, modifications and alterations are possible without departing from the technical details of this disclosure.

[0274] According to one embodiment of the present disclosure, an optical improvement layer including a first pattern layer and a second pattern layer with different pattern shapes and sizes is disposed on a display panel, thereby effectively preventing or suppressing flickering or graininess in the display device.

[0275] An optical sheet according to one embodiment of the present disclosure includes a first pattern layer and a second pattern layer with different pattern shapes and pattern sizes, and can be applied to a display panel to effectively prevent or suppress flickering or gritting phenomena in the display device.

[0276] According to this disclosure, flickering in the display device when the internal light-emitting element emits light (in the on state) can be effectively suppressed or prevented, and sand-like phenomena in the display device when external light is reflected from the display surface can be effectively suppressed or prevented.

[0277] According to one embodiment of this disclosure, flickering or graininess in a display device can be effectively prevented or suppressed, and the display device can have excellent display quality.

[0278] In addition to the effects described above, other features and advantages of this disclosure are described below, or may be clearly understood by those skilled in the art to which this disclosure pertains from such description and explanation.

Claims

1. A display device, comprising: A display panel with pixels; and The optical enhancement layer on the display panel; The optical improvement layer includes a first pattern layer and a second pattern layer that overlap each other. The first patterned layer has a first refractive index. The second patterned layer has a second refractive index that is different from the first refractive index. The average pattern size of the first pattern layer is greater than the average pattern size of the second pattern layer. Wherein, the average pattern ratio of the patterns contained in the first pattern layer is less than the average pattern ratio of the patterns contained in the second pattern layer. Wherein, the average pattern size is the average of the maximum diameters of the corresponding patterns in the planar images of the first pattern layer and the second pattern layer, respectively. In this context, for the patterns contained in the first pattern layer and the patterns contained in the second pattern layer, the ratio of each pattern is calculated as b / a, where a represents the maximum diameter of each pattern and b represents the height of each pattern. The average pattern ratio is calculated as the average pattern ratio of the corresponding pattern.

2. The display device of claim 1, wherein, The first pattern layer has multiple lens patterns. The second pattern layer includes multiple angular patterns.

3. The display device according to claim 1, wherein, The optical improvement layer also includes an intermediate layer located on the first patterning layer.

4. The display device according to claim 3, wherein, The intermediate layer contacts the first patterned layer. The refractive index difference between the first patterned layer and the intermediate layer is approximately 0.05 to approximately 0.

1.

5. The display device according to claim 3, wherein, The intermediate layer contacts the first pattern layer and the second pattern layer. The refractive index difference between the intermediate layer and the second patterned layer is approximately 0.01 or less.

6. The display device according to claim 3, wherein, The intermediate layer comprises the same material as the second patterned layer.

7. The display device according to claim 3, wherein, The intermediate layer is integrally formed with the second pattern layer.

8. The display device according to claim 7, wherein, The refractive index difference between the first patterned layer and the second patterned layer is about 0.05 to about 0.

1.

9. The display device according to claim 3, wherein, The optical improvement layer also includes a fill layer located on the second patterning layer.

10. The display device according to claim 9, wherein, The filler layer contacts the second pattern layer. The refractive index difference between the second patterned layer and the filling layer is approximately 0.05 to approximately 0.

1.

11. The display device according to claim 9, wherein, The intermediate layer and the fill layer are disposed between the first pattern layer and the second pattern layer.

12. The display device according to claim 11, wherein, The intermediate layer and the filler layer comprise the same material.

13. The display device according to claim 11, wherein, The optical improvement layer also includes a spacer disposed between the intermediate layer and the filler layer.

14. The display device according to claim 9, wherein, The filling layer is disposed between the first pattern layer and the second pattern layer.

15. The display device according to claim 14, wherein, The filler layer is integrally formed with the first pattern layer.

16. The display device according to claim 9, wherein, The first pattern layer contacts the second pattern layer. The protrusions of the first patterned layer and the protrusions of the second patterned layer protrude in opposite directions.

17. The display device according to claim 16, wherein, The first pattern layer and the second pattern layer are integrally formed.

18. The display device according to claim 9, wherein, The refractive index difference between the first patterned layer and the intermediate layer is equal to the refractive index difference between the second patterned layer and the filler layer.

19. The display device according to claim 9, further comprising: The cover substrate on the filler layer The filling layer has the same refractive index as the covering substrate.

20. The display device according to claim 1, wherein, The display panel includes an outer coating. The first pattern layer is disposed on the outer coating layer. The outer coating layer has the same refractive index as the first patterned layer.

21. The display device according to claim 1, wherein, The display panel includes a color filter layer. The optical enhancement layer is disposed on the color filter layer.

22. An optical improvement layer for a display device, comprising: The first and second pattern layers overlap each other. The first patterned layer has a first refractive index. The second patterned layer has a second refractive index that is different from the first refractive index. The average pattern size of the first pattern layer is greater than the average pattern size of the second pattern layer. Wherein, the average pattern ratio of the patterns contained in the first pattern layer is less than the average pattern ratio of the patterns contained in the second pattern layer. Wherein, the average pattern size is the average of the maximum diameters of the corresponding patterns in the planar images of the first pattern layer and the second pattern layer, respectively. In this context, for the patterns contained in the first pattern layer and the patterns contained in the second pattern layer, the ratio of each pattern is calculated as b / a, where a represents the maximum diameter of each pattern and b represents the height of each pattern. The average pattern ratio is calculated as the average pattern ratio of the corresponding pattern.

23. A display device, comprising: A display panel with pixels; and The optical enhancement layer on the display panel; The optical improvement layer includes a first patterning layer and a second patterning layer. The first patterning layer has a first refractive index and a first pattern, and the first pattern has a first average pattern ratio. The second patterning layer has a second refractive index and a second pattern, and the second pattern has a second average pattern ratio. Wherein, the first average pattern ratio is less than the second average pattern ratio. In this case, multiple second patterns overlap with one of the first patterns. Wherein, the average pattern ratio of each of the first pattern and the second pattern is the average of b / a, where a is the maximum diameter and b is the height of each of the first pattern and the second pattern.

Images