Patent Publication Number: US-2023165040-A1

Title: Display apparatus

Description:
CROSS-REFERENCE TO RELATED APPLICATION 
     This application claims priority to and the benefit of Korean Patent Application No. 10-2021-0160708, filed on Nov. 19, 2021, in the Korean Intellectual Property Office, the entire disclosure of which is incorporated by reference herein. 
     BACKGROUND 
     1. Field 
     Aspects of one or more embodiments of the present disclosure relate to a display apparatus, and more particularly, to a display apparatus capable of reducing the possibility of an occurrence of contamination between layers thereof. 
     2. Description of the Related Art 
     Electrodes and other metal wires of a display element included in a display apparatus may reflect light introduced from the outside. Accordingly, in such a display apparatus visibility may be decreased due to reflection of external light in a bright environment. 
     The above information disclosed in this Background section is for enhancement of understanding of the background of the present disclosure, and therefore, it may contain information that does not constitute prior art. 
     SUMMARY 
     In order to reduce reflection of external light, a display apparatus may include a color filter. 
     However, in such a display apparatus, a layer located on an upper portion of the display apparatus may be contaminated by a lower layer disposed below the layer. 
     One or more embodiments of the present disclosure are directed to a display apparatus capable of reducing the possibility of contamination between layers thereof. 
     However, the present disclosure is not limited to the aspects and features set forth above. Additional aspects and features will be set forth, in part, in the description that follows, and in part, will be apparent from the description, or may be learned by practicing one or more of the presented embodiments of the present disclosure. 
     According to one or more embodiments of the present disclosure, a display apparatus includes: a substrate; a display element on the substrate; an encapsulation layer on the display element, and including a dye and a first organic material; a first refractive layer on the encapsulation layer, and having an opening corresponding to the display element; and a second refractive layer covering the first refractive layer, the second refractive layer including a pigment and a second organic material, and having a refractive index different from a refractive index of the first refractive layer. 
     In an embodiment, the dye may be soluble in the second organic material, and the second refractive layer may not include the dye. 
     In an embodiment, an absorbance of the dye with respect to light in a wavelength band of greater than 575 nm and less than 605 nm may be greater than an absorbance of the dye with respect to light in a wavelength band of 605 nm to 650 nm. 
     In an embodiment, the pigment may be insoluble in the second organic material. 
     In an embodiment, an absorbance of the pigment with respect to light in a wavelength band of 380 nm to 480 nm may be greater than an absorbance of the pigment with respect to light in a wavelength band of 605 nm to 650 nm. 
     In an embodiment, the refractive index of the second refractive layer may be greater than the refractive index of the first refractive layer. 
     In an embodiment, the second refractive layer may include highly refractive particles including a metal oxide. 
     In an embodiment, the second refractive layer may fill the opening of the first refractive layer. 
     In an embodiment, the encapsulation layer may include a first inorganic encapsulation layer, an organic encapsulation layer on the first inorganic encapsulation layer, and a second inorganic encapsulation layer covering the organic encapsulation layer, and the organic encapsulation layer may include the dye and the first organic material. 
     In an embodiment, the display apparatus may further include a low-reflection layer between the display element and the encapsulation layer, and including an inorganic material. 
     In an embodiment, the display apparatus may further include an input sensing layer between the encapsulation layer and the first refractive layer, and including a sensing electrode. 
     In an embodiment, the display apparatus may further include a protective layer on the second refractive layer, and including a protective film and an adhesive material. 
     In an embodiment, the encapsulation layer may further include the pigment. 
     According to one or more embodiments of the present disclosure, a display apparatus includes: a substrate; a display element on the substrate; an encapsulation layer on the display element, and including a dye, a pigment, and a first organic material; a first refractive layer on the encapsulation layer, and having an opening corresponding to the display element; and a second refractive layer covering the first refractive layer, the second refractive layer including a second organic material, and having a refractive index different from a refractive index of the first refractive layer. 
     In an embodiment, the dye may be soluble in the second organic material, and the second refractive layer may not include the dye. 
     In an embodiment, an absorbance of the dye with respect to light in a wavelength band of greater than 575 nm and less than 605 nm may be greater than an absorbance of the dye with respect to light in a wavelength band of 605 nm to 650 nm. 
     In an embodiment, the pigment may be insoluble in the second organic material. 
     In an embodiment, an absorbance of the pigment with respect to light in a wavelength band of 380 nm to 480 nm may be greater than an absorbance of the pigment with respect to light in a wavelength band of 605 nm to 650 nm. 
     In an embodiment, the refractive index of the second refractive layer may be greater than the refractive index of the first refractive layer. 
     In an embodiment, the second refractive layer may include highly refractive particles including a metal oxide. 
     In an embodiment, the second refractive layer may fill the opening of the first refractive layer. 
     In an embodiment, the encapsulation layer may include a first inorganic encapsulation layer, an organic encapsulation layer on the first inorganic encapsulation layer, and a second inorganic encapsulation layer covering the organic encapsulation layer, and the organic encapsulation layer may include the dye, the pigment, and the first organic material. 
     In an embodiment, the display apparatus may further include a low-reflection layer between the display element and the encapsulation layer, and including an inorganic material. 
     In an embodiment, the display apparatus may further include an input sensing layer between the encapsulation layer and the first refractive layer, and including a sensing electrode. 
     In an embodiment, the display apparatus may further include a protective layer on the second refractive layer, and including a protective film and an adhesive material. 
     The above and/or other aspects and features will become more apparent and readily appreciated from the following detailed description of the embodiments, with reference to the accompanying drawings. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       The above and other aspects and features of the present disclosure will be more clearly understood from the following detailed description of the illustrative, non-limiting embodiments with reference to the accompanying drawings, in which: 
         FIG.  1    is a perspective view of a display apparatus according to an embodiment; 
         FIG.  2    is a schematic cross-sectional view of the display apparatus taken along the line I-I′ of  FIG.  1   ; 
         FIG.  3    is a cross-sectional view schematically illustrating light extraction efficiency of a display apparatus according to an embodiment; 
         FIG.  4    is a cross-sectional view schematically illustrating a portion of a display apparatus according to an embodiment; 
         FIG.  5    is a cross-sectional view schematically illustrating a portion of a display apparatus according to an embodiment; 
         FIGS.  6 - 7    are graphs illustrating transmittances according to wavelengths of a second refractive layer including a pigment, and an encapsulation layer including a dye of a display apparatus according to an embodiment; and 
         FIG.  8    is a graph illustrating a transmittance according to a wavelength of a second refractive layer including a pigment and a dye of a comparative example. 
     
    
    
     DETAILED DESCRIPTION 
     Hereinafter, embodiments will be described in more detail with reference to the accompanying drawings, in which like reference numbers refer to like elements throughout. The present disclosure, however, may be embodied in various different forms, and should not be construed as being limited to only the illustrated embodiments herein. Rather, these embodiments are provided as examples so that this disclosure will be thorough and complete, and will fully convey the aspects and features of the present disclosure to those skilled in the art. Accordingly, processes, elements, and techniques that are not necessary to those having ordinary skill in the art for a complete understanding of the aspects and features of the present disclosure may not be described. Unless otherwise noted, like reference numerals denote like elements throughout the attached drawings and the written description, and thus, redundant description thereof may not be repeated. 
     When a certain embodiment may be implemented differently, a specific process order may be different from the described order. For example, two consecutively described processes may be performed at the same or substantially at the same time, or may be performed in an order opposite to the described order. 
     In the drawings, the relative sizes of elements, layers, and regions may be exaggerated and/or simplified for clarity. Spatially relative terms, such as “beneath,” “below,” “lower,” “under,” “above,” “upper,” and the like, may be used herein for ease of explanation to describe one element or feature&#39;s relationship to another element(s) or feature(s) as illustrated in the figures. It will be understood that the spatially relative terms are intended to encompass different orientations of the device in use or in operation, in addition to the orientation depicted in the figures. For example, if the device in the figures is turned over, elements described as “below” or “beneath” or “under” other elements or features would then be oriented “above” the other elements or features. Thus, the example terms “below” and “under” can encompass both an orientation of above and below. The device may be otherwise oriented (e.g., rotated 90 degrees or at other orientations) and the spatially relative descriptors used herein should be interpreted accordingly. 
     In the figures, the x-axis, the y-axis, and the z-axis are not limited to three axes of the rectangular coordinate system, and may be interpreted in a broader sense. For example, the x-axis, the y-axis, and the z-axis may be perpendicular to or substantially perpendicular to one another, or may represent different directions from each other that are not perpendicular to one another. 
     It will be understood that, although the terms “first,” “second,” “third,” etc., may be used herein to describe various elements, components, regions, layers and/or sections, these elements, components, regions, layers and/or sections should not be limited by these terms. These terms are used to distinguish one element, component, region, layer or section from another element, component, region, layer or section. Thus, a first element, component, region, layer or section described below could be termed a second element, component, region, layer or section, without departing from the spirit and scope of the present disclosure. 
     It will be understood that when an element or layer is referred to as being “on,” “connected to,” or “coupled to” another element or layer, it can be directly on, connected to, or coupled to the other element or layer, or one or more intervening elements or layers may be present. Similarly, when a layer, an area, or an element is referred to as being “electrically connected” to another layer, area, or element, it may be directly electrically connected to the other layer, area, or element, and/or may be indirectly electrically connected with one or more intervening layers, areas, or elements therebetween. In addition, it will also be understood that when an element or layer is referred to as being “between” two elements or layers, it can be the only element or layer between the two elements or layers, or one or more intervening elements or layers may also be present. 
     The terminology used herein is for the purpose of describing particular embodiments and is not intended to be limiting of the present disclosure. As used herein, the singular forms “a” and “an” are intended to include the plural forms as well, unless the context clearly indicates otherwise. It will be further understood that the terms “comprises,” “comprising,” “includes,” “including,” “has,” “have,” and “having,” when used in this specification, specify the presence of the stated features, integers, steps, operations, elements, and/or components, but do not preclude the presence or addition of one or more other features, integers, steps, operations, elements, components, and/or groups thereof. As used herein, the term “and/or” includes any and all combinations of one or more of the associated listed items. For example, the expression “A and/or B” denotes A, B, or A and B. Expressions such as “at least one of,” when preceding a list of elements, modify the entire list of elements and do not modify the individual elements of the list. For example, the expression “at least one of a, b, or c,” “at least one of a, b, and c,” and “at least one selected from the group consisting of a, b, and c” indicates only a, only b, only c, both a and b, both a and c, both b and c, all of a, b, and c, or variations thereof. 
     As used herein, the term “substantially,” “about,” and similar terms are used as terms of approximation and not as terms of degree, and are intended to account for the inherent variations in measured or calculated values that would be recognized by those of ordinary skill in the art. Further, the use of “may” when describing embodiments of the present disclosure refers to “one or more embodiments of the present disclosure.” As used herein, the terms “use,” “using,” and “used” may be considered synonymous with the terms “utilize,” “utilizing,” and “utilized,” respectively. 
     Unless otherwise defined, all terms (including technical and scientific terms) used herein have the same meaning as commonly understood by one of ordinary skill in the art to which the present disclosure belongs. It will be further understood that terms, such as those defined in commonly used dictionaries, should be interpreted as having a meaning that is consistent with their meaning in the context of the relevant art and/or the present specification, and should not be interpreted in an idealized or overly formal sense, unless expressly so defined herein. 
       FIG.  1    is a perspective view of a portion of a display apparatus  1  according to an embodiment. 
     Referring to  FIG.  1   , the display apparatus  1  may include a display area DA, and a peripheral area PA surrounding (e.g., around a periphery of) the display area DA. The display apparatus  1  may provide an image through an array of a plurality of pixels that are two-dimensionally arranged at (e.g., in or on) the display area DA. 
     Each pixel of the display apparatus  1  is an area capable of emitting light of a desired color (e.g., a certain or predetermined color), and the display apparatus  1  may provide an image using light emitted from the pixels. For example, each pixel may emit red, green, or blue light. 
     The display area DA may have a suitable polygonal shape including a quadrangle as shown in  FIG.  1   . For example, the display area DA may have a rectangular shape having a horizontal length greater than a vertical length thereof, a rectangular shape having a horizontal length less than a vertical length thereof, or a square shape. However, the display area DA may have various suitable shapes, for example, such as an ellipse or a circle. 
     The peripheral area PA is a non-display area that does not provide an image, and may surround (e.g., around a periphery of) the display area DA. A driver or a main power line for providing an electrical signal or power to pixel circuits may be arranged at (e.g., in or on) the peripheral area PA. The peripheral area PA may include a pad, which is an area to which an electronic device or a printed circuit board may be electrically connected. 
     Hereinafter, according to an embodiment, an organic light-emitting display apparatus is described as an example of the display apparatus  1 , but the present disclosure is not limited thereto. In another embodiment, the display apparatus  1  may be an inorganic light-emitting display apparatus (or an inorganic EL display apparatus) or a quantum dot light-emitting display apparatus. For example, an emission layer of a display element included in the display apparatus  1  may include an organic material or an inorganic material. As another example, the display apparatus  1  may include an emission layer, and a quantum dot layer on a path of light emitted from the emission layer. 
       FIG.  2    is a schematic cross-sectional view of a portion of the display apparatus  1  according to an embodiment. In more detail,  FIG.  2    is a cross-sectional view of the display apparatus  1  taken along the line I-I′ of  FIG.  1   . 
     Referring to  FIG.  2   , the display apparatus  1  may include a substrate  100 , a display element layer  200 , a low reflection layer  300 , an encapsulation layer  400 , an input sensing layer  500 , a refractive layer  700 , and a protective layer  800 . 
     The substrate  100  may include glass, metal, or a polymer resin. The substrate  100  may have flexible and/or bendable characteristics. In this case, the substrate  100  may include, for example, a polymer resin such as polyethersulphone, polyacrylate, polyetherimide, polyethylene naphthalate, polyethylene terephthalate, polyphenylene sulfide, polyarylate, polyimide, polycarbonate, or cellulose acetate propionate. In addition, the substrate  100  may have a multilayered structure including two layers including the polymer resin, and a barrier layer including an inorganic material (e.g., such as silicon oxide, silicon nitride, silicon oxynitride, and/or the like) between the two layers, but various modifications may be made thereto. 
     A buffer layer  110  including silicon oxide, silicon nitride, or silicon oxynitride may be disposed on the substrate  100 . The buffer layer  110  may serve to increase a smoothness of an upper surface of the substrate  100 , and may prevent or substantially prevent diffusion of metal atoms and/or impurities from the substrate  100  to a semiconductor layer  210  disposed thereon. The buffer layer  110  may include (e.g., may be) a single layer or multiple layers including silicon oxide, silicon nitride, or silicon oxynitride. 
     The display element layer  200  may be on the buffer layer  110 . The display element layer  200  may include a display element  290 , and a thin-film transistor TFT electrically connected to the display element  290 . In  FIG.  2   , an organic light-emitting device is shown as an example of the display element  290  on the buffer layer  110 . The organic light-emitting device is electrically connected to the thin-film transistor TFT. For example, a pixel electrode  291  of the organic light-emitting device is electrically connected to the thin-film transistor TFT. 
     As shown in  FIG.  2   , the thin-film transistor TFT includes the semiconductor layer  210 , a gate electrode  230 , a source electrode  251 , and a drain electrode  252 . The semiconductor layer  210  may include amorphous silicon, polycrystalline silicon, an oxide semiconductor material, or an organic semiconductor material. A gate-insulating layer  220  may be between the semiconductor layer  210  and the gate electrode  230 , to insulate the semiconductor layer  210  from the gate electrode  230 . The gate-insulating layer  220  may include an inorganic material, such as silicon oxide, silicon nitride, and/or silicon oxynitride. A first interlayer insulating layer  240  may be on the gate electrode  230 . The first interlayer-insulating layer  240  may include an inorganic material, such as silicon oxide, silicon nitride, and/or silicon oxynitride. The source electrode  251  and the drain electrode  252  may be on the first interlayer-insulating layer  240 , and may penetrate the first interlayer-insulating layer  240  to be connected to the semiconductor layer  210 . A second interlayer insulating layer  260  may be disposed to cover the source electrode  251  and the drain electrode  252 . 
     A planarization layer  270  may be on the thin-film transistor TFT. For example, as shown in  FIG.  2   , when the organic light-emitting device is on the thin-film transistor TFT, the planarization layer  270  may generally flatten (e.g., may flatten or substantially flatten) an upper portion (e.g., an upper surface) of the thin-film transistor TFT. The planarization layer  270  may include an organic material, such as acryl, benzocyclobutene (BCB), or hexamethyldisiloxane (HMDSO). Although the planarization layer  270  is shown as a monolayer in  FIG.  2   , the planarization layer  140  may be multilayered, and various suitable modifications thereto may be made. 
     The display element  290  may be on the planarization layer  270  at (e.g., in or on) the display area DA of the display element layer  200 . The display element  290  may be, for example, an organic light-emitting device including the pixel electrode  291 , an opposite electrode  293 , and an intermediate layer  292  including an emission layer interposed between the pixel electrode  291  and the opposite electrode  293 . 
     As shown in  FIG.  2   , the pixel electrode  291  is electrically connected to the thin-film transistor TFT by contacting any one of the source electrode  251  and the drain electrode  252  through an opening formed in (e.g., penetrating) the planarization layer  270  and/or the like. The pixel electrode  291  includes a light-transmitting conductive layer formed of a light-transmitting conductive oxide, for example, such as ITO, In 2 O 3 , or IZO, and a reflective layer formed of a metal, for example, such as Al or Ag. For example, the pixel electrode  291  may have a three-layered structure of ITO/Ag/ITO. 
     A pixel-defining layer  280  may be on the planarization layer  270 . The pixel defining layer  280  defines a pixel (e.g., a pixel area) by having a first opening  280 OP corresponding to each pixel, or in other words, a corresponding first opening  280 OP exposing at least a center of the pixel electrode  291  of each pixel. Furthermore, as shown in  FIG.  2   , the pixel-defining layer  280  prevents or substantially prevents the generation of an arc and/or the like at an edge of the pixel electrode  291  by increasing a distance between the edge of the pixel electrode  291  and the opposite electrode  293  disposed over the pixel electrode  291 . The pixel-defining layer  280  may include an organic material, such as polyimide or HMDSO. 
     The intermediate layer  292  of the organic light-emitting device may include a low-molecular weight material, or a high molecular weight material such as a polymer material. When the intermediate layer  292  includes a low-molecular weight material, the intermediate layer  292  may have a single or composite structure by stacking a hole injection layer (HIL), a hole transport layer (HTL), an emission layer (EML), an electron transport layer (ETL), and an electron injection layer (EIL), and may be formed by a vacuum deposition method. When the intermediate layer  292  includes a high molecular weight material, for example, such as a polymer material, the intermediate layer  292  may have a structure including an HTL and an EML. The HTL may include PEDOT, and the EML may include a polymer material, for example, such as poly-phenylenevinylene (PPV) and/or polyfluorene. The intermediate layer  292  may be formed by using a screen printing method, an ink jet printing method, or a laser induced thermal imaging (LITI) method. However, the intermediate layer  292  is not limited thereto, and may have various suitable structures. In addition, the intermediate layer  292  may include an integral layer over a plurality of pixel electrodes  291 , or may have a layer that is patterned to correspond to each of the pixel electrodes  291 . 
     The opposite electrode  293  may be on the display area DA to cover the display area DA. In other words, the opposite electrode  293  may be integrally formed for a plurality of organic light-emitting devices to correspond to a plurality of pixel electrodes  291 . The opposite electrode  293  may include a light-transmitting conductive layer formed of ITO, In 2 O 3 , or IZO, and/or a semi-transparent film including a metal, such as Al or Ag. For example, the opposite electrode  293  may be a semi-transparent film including Mg or Ag. 
     The low reflection layer  300  may be on the display element layer  200 . In more detail, the low reflection layer  300  may be between the display element layer  200  and the encapsulation layer  400 . The low reflection layer  300  may include an inorganic material having a low reflectance. The low reflection layer  300  may include, for example, ytterbium (Yb), bismuth (Bi), cobalt (Co), molybdenum (Mo), titanium (Ti), zirconium (Zr), aluminum (Al), chromium (Cr), niobium (Nb), platinum (Pt), tungsten 
     (W), indium (In), tin (Sn), iron (Fe), nickel (Ni), tantalum (Ta), manganese (Mn), zinc (Zn), germanium (Ge), or a suitable combination thereof. The inorganic material included in the low reflection layer  300  may have an absorption coefficient of 0.5 or more. 
     The low reflection layer  300  may induce a destructive interference between light incident into the display apparatus  1  and light reflected by a metal below the low reflection layer  300 , to reduce external light reflection. Accordingly, by reducing external light reflectance of the display apparatus  1  through the low reflection layer  300 , display quality and visibility of the display apparatus  1  may be improved. 
     The encapsulation layer  400  may be on the low reflection layer  300 . The encapsulation layer  400  may cover the display area DA, and may extend to the outside of the display area DA. The encapsulation layer  400  may include a first inorganic encapsulation layer  410 , an organic encapsulation layer  420 , and a second inorganic encapsulation layer  430  as shown in  FIG.  2   . 
     The first inorganic encapsulation layer  410  covers the low reflection layer  300 , and may include silicon oxide, silicon nitride, and/or silicon oxynitride. A shape of the first inorganic encapsulation layer  410  is formed in accordance with a shape of a structure disposed therebelow, and thus, as shown in  FIG.  2   , an upper surface of the first inorganic encapsulation layer  410  is not flat. 
     The organic encapsulation layer  420  covers the first inorganic encapsulation layer  410 . However, unlike the first inorganic encapsulation layer  410 , an upper surface of the organic encapsulation layer  420  may be formed to be generally flat (e.g., to be flat or substantially flat). In more detail, the upper surface of the organic encapsulation layer  420  corresponding to the display area DA may be approximately flat (e.g., may be flat or substantially flat). The organic encapsulation layer  420  may include a first organic material. The first organic material may include, for example, at least one of polyethylene terephthalate, polyethylene naphthalate, polycarbonate, polyimide, polyethylene sulfonate, polyoxymethylene, polyarylate, hexamethyldisiloxane, an epoxy resin, and an acrylic resin (e.g., polymethyl methacrylate, polyacrylic acid, and/or the like). 
     The second inorganic encapsulation layer  430  covers the organic encapsulation layer  420 , and may include silicon oxide, silicon nitride, and/or silicon oxynitride. The second inorganic encapsulation layer  430  may prevent or substantially prevent the organic encapsulation layer  420  from being exposed to the outside, because the second inorganic encapsulation layer  430  contacts an edge of the first inorganic encapsulation layer  410  located outside the display area DA. 
     Because the encapsulation layer  400  has a multilayered structure including the first inorganic encapsulation layer  410 , the organic encapsulation layer  420 , and the second inorganic encapsulation layer  430 , even if a crack occurs in the encapsulation layer  400 , the crack may not be connected between the first inorganic encapsulation layer  410  and the organic encapsulation layer  420 , or between the organic encapsulation layer  420  and the second inorganic encapsulation layer  430  through the multilayered structure. As such, the formation of a penetration path of external moisture and/or oxygen into the display area DA may be prevented or reduced. Because the organic light-emitting device may be easily damaged by moisture and/or oxygen from the outside, the encapsulation layer  400  may cover and protect the organic light-emitting device and/or the low reflection layer  300 . 
     The organic encapsulation layer  420  may include a dye. Accordingly, the organic encapsulation layer  420  may absorb some of the incident light incident from the outside, or may absorb some of reflected light that proceeds to the outside after the incident light from the outside is reflected by structures below the organic encapsulation layer  420 . Therefore, even if the display apparatus  1  does not include a retarder and/or a polarizer, external light reflection may be reduced. The dye may include, for example, a metal porphyrin compound, a methine compound, a triazine compound, a pyrromethene compound, a tetra-azaporphyrin compound, a phthalocyanine compound, and/or a suitable combination thereof. 
     The dye included in the organic encapsulation layer  420  is soluble in the first organic material, and may be dissolved in the first organic material. As used herein, the phrase “A is soluble in B” means that an attractive force between A particles is equal to or less than an attractive force between A and B particles or an attractive force between B particles. In addition, the phrase “A dissolves in B” means that A particles diffuse and are uniformly or substantially uniformly distributed in a material containing B. In other words, dye particles may be diffused in the first organic material and may be uniformly or substantially uniformly distributed in the first organic material. 
     On the other hand, when a layer in contact with the organic encapsulation layer  420  contains a material capable of dissolving the dye, the dye included in the organic encapsulation layer  420  may move to and contaminate the layer in contact with the organic encapsulation layer  420 . However, according to the present embodiment, because the organic encapsulation layer  420  including the dye is surrounded (e.g., is enclosed) by the first inorganic encapsulation layer  410  and the second inorganic encapsulation layer  430 , the dye included in the organic encapsulation layer  420  may be prevented or substantially prevented from passing through the first inorganic encapsulation layer  410  and/or the second inorganic encapsulation layer  430  and moving to another layer. In other words, because contamination between layers of the display apparatus  1  may be prevented or substantially prevented, chemical resistance of the display apparatus  1  may be improved. 
     The input sensing layer  500  may be on the encapsulation layer  400 . In more detail, the input sensing layer  500  may be between the encapsulation layer  400  and a light blocking layer  600 . A first refractive layer  710  may be on the light blocking layer  600 . The input sensing layer  500  may obtain coordinate information according to an external input, for example, such as a touch event of an object such as a finger or a stylus pen. The input sensing layer  500  may include sensing electrodes and/or trace lines. The input sensing layer  500  may sense the external input using a mutual capacitance method or a self-capacitance method. 
     The input sensing layer  500  may include a first touch-insulating layer  510 , a first conductive layer  521 , a second touch-insulating layer  530 , and a second conductive layer  522 . The first conductive layer  521  and the second conductive layer  522  may include sensing electrodes and/or trace lines. The first touch-insulating layer  510  may be between the encapsulation layer  400  and the first conductive layer  521 , and the second touch-insulating layer  530  may be between the first conductive layer  521  and the second conductive layer  522 . 
     The first conductive layer  521  and the second conductive layer  522  may each be a single layer or multiple layers including a conductive material. The conductive material may include Mo, Al, copper (Cu), or Ti. For example, the first conductive layer  521  and the second conductive layer  522  may each have a three-layer structure of Ti/Al/Ti. 
     The first touch-insulating layer  510  and the second touch-insulating layer  530  may include an inorganic insulating material and/or an organic insulating material. The inorganic insulating material may include silicon oxide, silicon nitride, and/or silicon oxynitride. The organic insulating material may include an acryl-based or imide-based organic material. 
     The light blocking layer  600  may be on the input sensing layer  500 . In more detail, the light blocking layer  600  may be disposed to cover the second conductive layer  522 . The light blocking layer  600  may include a second opening  600 OP corresponding to an emission area EA of the display element  290 . The light blocking layer  600  may have a plurality of second openings  600 OP to have a grid shape or a mesh shape. A width (e.g., in the x direction or the y direction) of the second opening  600 OP of the light blocking layer  600  may be greater than a width (e.g., in the x direction or the y direction) of the first opening  280 OP of the pixel-defining layer  280 . A shape of the second opening  600 OP of the light blocking layer  600  may be the same or substantially the same as a shape of the first opening  280 OP of the pixel-defining layer  280 . 
     The light blocking layer  600  may include a light blocking material, for example, such as a black material. The light blocking material may include carbon black, carbon nanotubes, a resin or paste containing a black dye, or metal particles. The metal particles may be, for example, nickel, aluminum, molybdenum, and/or suitable alloys thereof. In addition, the light blocking material may include metal oxide particles such as chromium oxide, or metal nitride particles such as chromium nitride. Because the light blocking layer  600  includes the light blocking material, reflection of external light by metal structures below the light blocking layer  600  may be reduced. If necessary or desired, the light blocking layer  600  may include the same or substantially the same material as that of the pixel defining layer  280  disposed therebelow. However, the present disclosure is not limited thereto, and the light blocking layer  600  may include a material different from that of the pixel-defining layer  280 . 
     The refractive layer  700  may be on the display element  290 , for example, such as on the input sensing layer  500 . The refractive layer  700  may control a path of light emitted from the emission layer of the display element  290 , and may serve as a condensing lens. The refractive layer  700  may change a path of light that travels in a lateral direction (e.g., a direction other than the +z direction) from among the light emitted from the emission layer of the display element  290 , to advance in a direction (e.g., the +z direction) that is perpendicular to or substantially perpendicular to a surface (e.g., the top surface) of the substrate  100 . The refractive layer  700  may include a first refractive layer  710  and a second refractive layer  720 . 
     The first refractive layer  710  may be on the light blocking layer  600 . The first refractive layer  710  may have a third opening  710 OP corresponding to the second opening  600 OP of the light blocking layer  600 . Accordingly, the third opening  710 OP of the first refractive layer  710  may correspond to the emission area EA of the display element  290 . In other words, the first refractive layer  710  may have a grid shape or a mesh shape by including a plurality of third openings  710 OP. A width (e.g., in the x direction or the y direction) of the third opening  710 OP of the first refractive layer  710  may be greater than the width (e.g., in the x direction or the y direction) of the first opening  280 OP of the pixel-defining layer  280 , and less than the width (e.g., in the x direction or the y direction) of the second opening  600 OP of the light blocking layer  600 . A shape of the third opening  710 OP of the first refractive layer  710  may be the same or substantially the same as the shapes of the first opening  280 OP of the pixel-defining layer  280  and the second opening  600 OP of the light blocking layer  600 . 
     The first refractive layer  710  may include a light-transmitting inorganic material or an organic material having a low refractive index. For example, the inorganic material may include silicon oxide, magnesium fluoride, and/or the like. The organic material may include at least one of acrylic, polyimide, polyamide, and Alq3 (Tris(8-hydroxyquinolinato)aluminum). A first refractive index of the first refractive layer  710  may be less than 1.6. For example, the first refractive index may be greater than 1.3 and less than 1.6. However, the present disclosure is not limited thereto. 
     The second refractive layer  720  may be on the first refractive layer  710 , and may fill the third opening  710 OP of the first refractive layer  710 . For example, the second refractive layer  720  may cover the first refractive layer  710 . The second refractive layer  720  may cover an entirety of an upper surface of the substrate  100 , and the upper surface of the second refractive layer  720  may be flat or substantially flat. 
     The second refractive layer  720  may include a second organic material. The second organic material may include at least one of polyethylene terephthalate, polyethylene naphthalate, polycarbonate, polyimide, polyethylene sulfonate, polyoxymethylene, polyarylate, hexamethyldisiloxane, an epoxy resin, and an acrylic resin (e.g., polymethyl methacrylate, polyacrylic acid, and/or the like). The dye included in the organic encapsulation layer  420  may be soluble in the second organic material. In other words, dye particles may be diffused in the second organic material, and may be uniformly or substantially uniformly distributed in the second organic material. However, in the case of the display apparatus  1  according to the present embodiment, the second refractive layer  720  may not include a dye. Accordingly, even if a layer in contact with the second refractive layer  720  contains a material in which the dye may be dissolved, the dye does not move to and contaminate the layer in contact with the second refractive layer  720 . Accordingly, because contamination between the layers of the display apparatus  1  may be prevented or substantially prevented, chemical resistance of the display apparatus  1  may be improved. 
     The second refractive layer  720  may include a plurality of highly refractive particles  730  dispersed in the second organic material. The highly refractive particles  730  may include a metal oxide, such as zirconium oxide, zinc oxide, titanium oxide, niobium oxide, tantalum oxide, tin oxide, nickel oxide, silicon nitride, indium nitride, gallium nitride, and/or the like. The highly refractive particles  730  may be dispersed in the second refractive layer  720  in a spherical or amorphous shape. When the highly refractive particles  730  are spherically dispersed in the second refractive layer  720 , an average diameter of the highly refractive particles  730  may be 5 nm to 30 nm. 
     Because the second refractive layer  720  includes the highly refractive particles  730 , the second refractive layer  720  may have a second refractive index greater than the first refractive index of the first refractive layer  710 . The second refractive index of the second refractive layer  720  may be greater than 1.6. The second refractive index may be, for example, greater than 1.6 and less than 2.0, but the present disclosure is not limited thereto. 
     In addition, the second refractive layer  720  may include a pigment  900 . The pigment  900  may include, for example, pigment red 177 (C.I Pigment red 177), pigment green 7 (C.I Pigment Green 7), pigment green 59 (C.I Pigment Green 59), pigment yellow 185 (C.I Pigment Yellow 185), and/or pigment blue 15:6 (C.I Pigment Blue 15:6). The pigment  900  is insoluble in the second organic material, and may be evenly or substantially evenly dispersed in the second organic material. As used herein, the phrase “A is insoluble in B” means that an attractive force between A particles is greater than an attractive force between the A particles and B particles or an attractive force between B particles. In addition, the phrase “A is evenly dispersed in B” means that A fine particles having a size in a suitable range (e.g., a specific or predetermined range) are mixed in a dispersion medium B without agglomeration. In other words, the pigment  900  may not be dissolved in the second organic material, but may be evenly or substantially evenly dispersed in the second organic material in the form of fine particles. 
     Accordingly, the pigment  900  having the form of fine particles is dispersed in the second refractive layer  720  to generate a similar effect as that of the highly refractive particles  730 . In other words, the pigment  900  may increase the second refractive index of the second refractive layer  720 . In addition, because the pigment  900  is not dissolved in the second organic material, the pigment  900  is not easily diffused or moved in the second refractive layer  720 . Furthermore, even if the pigment  900  included in the second refractive layer  720  moves to a layer in contact with the second refractive layer  720 , the pigment  900  may not contaminate the layer. Accordingly, because contamination between the layers of the display apparatus  1  may be prevented or substantially prevented, chemical resistance of the display apparatus  1  may be improved. 
     The protective layer  800  may be on the second refractive layer  720 . The protective layer  800  may include a protective film and an adhesive material. The protective film may include a plastic film, for example, such as polyethylene terephthalate. The adhesive material may include, for example, a silicone-based adhesive material or a urethane-based adhesive material. However, the present disclosure is not limited thereto. 
     The dye may be soluble in the protective film and/or the adhesive material included in the protective layer  800 . In other words, when a layer including dye particles is in contact with the protective layer  800 , the dye particles may migrate into the protective film and/or the adhesive material included in the protective layer  800  to contaminate the protective film and/or the adhesive material. For example, when the second refractive layer  720  that is in contact with the protective layer  800  includes a dye, the dye may move to and contaminate the passivation layer  800 , and may chemically react with the passivation layer  800 . 
     However, in the case of the display apparatus  1  according to the present embodiment, the dye is located in the organic encapsulation layer  420 , and the second refractive layer  720  does not include a dye. Therefore, even if the passivation layer  800  that is in contact with the second refractive layer  720  contains a material capable of dissolving a dye, the dye does not move to and contaminate the passivation layer  800 . Accordingly, because contamination between the layers of the display apparatus  1  may be prevented or substantially prevented, chemical resistance of the display apparatus  1  may be improved. 
       FIG.  3    is a cross-sectional view schematically illustrating a portion of a display apparatus according to an embodiment. In more detail,  FIG.  3    is a cross-sectional view schematically illustrating light extraction efficiency of the display apparatus  1  according to an embodiment. As shown in  FIG.  3   , a width (e.g., in the x direction or they direction) of the bottom of the third opening  710 OP may be greater than a width (e.g., in the x direction or the y direction) of the bottom of the first opening  280 OP, and less than a width (e.g., in the x direction or the y direction) of the bottom of the second opening  600 OP. The width may refer to the maximum width of the bottom of the corresponding opening. However, the present disclosure is not limited thereto. 
     Light emitted from the display element  290  may include light L 1  that is obliquely incident toward a side surface of the first refractive layer  710 , and light L 3  that passes through the second refractive layer  720  and is extracted in a direction (e.g., the +z direction) that is perpendicular to or substantially perpendicular to the substrate  100  (e.g., to the top surface of the substrate  100 ) without changing the direction. From among the light emitted from the display element  290 , the light L 1  incident toward the inclined side surface of the first refractive layer  710  may be totally reflected at an interface between the first refractive layer  710  and the second refractive layer  720  to change an optical path thereof. From the total reflection of the light L 1 , totally reflected light L 2  may be extracted in the direction (e.g., the +z direction) that is perpendicular to or substantially perpendicular to the substrate  100 . In other words, by the total reflection of the light L 1  at the interface between the first refractive layer  710  having a first refractive index and the second refractive layer  720  having a second refractive index greater than the first refractive index, front light extraction efficiency may be improved, and thus, front visibility may be improved. 
       FIG.  4    is a cross-sectional view schematically illustrating a portion of a display apparatus according to an embodiment. 
     According to one or more embodiments described above, the organic encapsulation layer  420  includes the dye, and the second refractive layer  720  includes the pigment  900 . However, the present disclosure is not limited thereto. For example, referring to  FIG.  4   , in some embodiments, the organic encapsulation layer  420  may include some pigments  900 , in addition to the dye, and the second refractive layer  720  may include some of the pigments  900 . 
     Even in the embodiment shown in  FIG.  4   , because the organic encapsulation layer  420  including the dye is surrounded (e.g., is enclosed) by the first inorganic encapsulation layer  410  and the second inorganic encapsulation layer  430 , the dye included in the organic encapsulation layer  420  may be prevented or substantially prevented from passing through the first inorganic encapsulation layer  410  and/or the second inorganic encapsulation layer  430  and moving to another layer. Accordingly, because contamination between the layers of the display apparatus  1  may be prevented or substantially prevented, chemical resistance of the display apparatus  1  may be improved. Furthermore, some of the pigments  900  included in the second refractive layer  720  increases a refractive index of the second refractive layer  720 . However, compared to the case where the second refractive layer  720  includes all of the pigments  900  as shown in  FIG.  2   , the refractive index of the second refractive layer  720  may be relatively low. 
     On the other hand, compared to the case where the second refractive layer  720  includes all of the pigments  900  as shown in  FIG.  2   , because some of the pigments  900  is included in the organic encapsulation layer  420 , the display apparatus  1  also has the same or similar external light reflectance. In other words, by adjusting the amount of the pigments  900  included in each of the organic encapsulation layer  420  and the second refractive layer  720 , the display apparatus  1  may have the same or similar external light reflectance as the case where the second refractive layer  720  includes all of the pigments  900 , and the refractive index of the second refractive layer  720  may be appropriately adjusted. 
       FIG.  5    is a cross-sectional view schematically illustrating a portion of a display apparatus according to an embodiment. 
     For example, as shown in  FIG.  5   , in some embodiments, the organic encapsulation layer  420  may include both the pigments  900  and the dye, and the second refractive layer  720  may include neither the pigments  900  nor the dye. 
     Even in the embodiment shown in  FIG.  5   , because the organic encapsulation layer  420  including the dye is surrounded (e.g., is enclosed) by the first inorganic encapsulation layer  410  and the second inorganic encapsulation layer  430 , the dye included in the organic encapsulation layer  420  may be prevented or substantially prevented from passing through the first inorganic encapsulation layer  410  and/or the second inorganic encapsulation layer  430  and moving to another layer. In addition, the dye is located in the organic encapsulation layer  420 , and the second refractive layer  720  does not include the dye. Therefore, even if the passivation layer  800  that is in contact with the second refractive layer  720  contains a material capable of dissolving the dye, the dye does not move to and contaminate the passivation layer  800 . Accordingly, because contamination between the layers of the display apparatus  1  may be prevented or substantially prevented, chemical resistance of the display apparatus  1  may be improved. 
       FIG.  6    is a graph illustrating a transmittance according to a wavelength of the organic encapsulation layer  420  including a dye of the display apparatus  1  according to an embodiment. In more detail,  FIG.  6    is a graph showing transmittance in the case of the organic encapsulation layer  420  including FDB-002™ (Yamada Kagaku Kogyo Co., Ltd.) or NEC594™ (Ukseung Chemicals) as the dye. 
     The organic encapsulation layer  420  including the above-described dye may absorb light of at least some wavelength bands that do not belong to a main wavelength range of the light emitted from the display element  290 . The display element  290  may emit red, green, blue, or white light. In this case, a wavelength band of the blue light emitted by the display element  290  may be about 430 nm to about 480 nm, a wavelength band of the green light emitted from the display element  290  may be about 510 nm to about 575 nm, and a wavelength band of the red light emitted by the display element  290  may be about 605 nm to about 650 nm. Accordingly, the organic encapsulation layer  420  may absorb light in at least one of a first wavelength band that is less than about 430 nm, a second wavelength band that is greater than about 480 nm and less than 510 nm, a third wavelength band that is greater than about 575 nm and less than 605 nm, and a fourth wavelength band that is greater than 650 nm. For example, absorbance of the dye included in the organic encapsulation layer  420  with respect to the light in the third wavelength band of greater than 575 nm and less than 605 nm may be greater than the absorbance of the dye included in the organic encapsulation layer  420  with respect to the light in the wavelength band of 605 nm to 650 nm. However, the present disclosure is not limited thereto. 
     For example, the organic encapsulation layer  620  may include at least one of a first dye for absorbing the light in the first wavelength band, a second dye for absorbing the light in the second wavelength band, a third dye for absorbing the light in the third wavelength band, and a fourth dye for absorbing the light in the fourth wavelength band. The first dye may include (e.g., may be) a metal porphyrin compound, a methine compound, a triazine compound, and/or suitable combinations thereof. The second dye may include (e.g., may be) a pyrromethene compound. The third dye may include (e.g., may be) a tetra-azaporphyrin compound. The fourth dye may include (e.g., may be) a phthalocyanine compound. However, the present disclosure is not limited thereto. FDB-002™ (Yamada Kagaku Kogyo Co., Ltd.) included in the organic encapsulation layer  420  of the display apparatus  1  according to the present embodiment is the first dye, and NEC594™ (Ukseung Chemicals) included in the organic encapsulation layer  420  of the display apparatus  1  according to the present embodiment is the third dye. Accordingly, as shown in  FIG.  6   , the organic encapsulation layer  420  absorbs the light in the first wavelength band of less than about 430 nm, and the light in the third wavelength band of greater than about 575 nm and less than about 605 nm. 
     When the organic encapsulation layer  420  includes at least two of the first dye, the second dye, the third dye, and the fourth dye, the quality of an image implemented in the display apparatus may be improved. When the dye included in the organic encapsulation layer  420  absorbs only external light belonging to the first wavelength band of less than about 430 nm, in the reflected light incident from the display apparatus, the amount of light belonging to the third wavelength band of greater than about 575 nm and less than about 605 nm is relatively greater than the amount of light belonging to the first wavelength band of less than about 430 nm. Accordingly, a user may recognize that the external light is relatively red, which may result in recognizing that the image implemented in the display apparatus is red as a whole. Therefore, by allowing the organic encapsulation layer  420  to include at least two of the first dye, the second dye, the third dye, and the fourth dye, the quality of the image implemented in the display apparatus may be significantly improved. 
       FIG.  7    is a graph illustrating a transmittance according to a wavelength of the second refractive layer  720  including a pigment of the display apparatus  1  according to an embodiment. In more detail, the graph of  FIG.  7    illustrates a transmittance when the second refractive layer  720  includes pigment yellow 185 (C.I Pigment Yellow 185) as the pigment  900 . 
     The second refractive layer  720  of the display apparatus  1  according to the present embodiment absorbs light in a wavelength range of 380 nm to 480 nm. For example, absorbance of the pigment  900  included in the second refractive layer  720  with respect to light in a wavelength band of 380 nm to 480 nm may be greater than absorbance of the pigment  900  included in the second refractive layer  720  with respect to light in a wavelength band of 605 nm to 650 nm. However, the present disclosure is not limited thereto. By including the second refractive layer  720  containing the pigment  900 , the display apparatus  1  including the organic encapsulation layer  420  containing the dye has the same or similar external light reflectance as that of the display apparatus  1  including the second refractive layer  720  containing a dye and the pigment  900 . 
       FIG.  8    is a graph illustrating a transmittance according to a wavelength of the second refractive layer  720  in a display apparatus according to a comparative example, in which the second refractive layer  720  includes both a dye and a pigment. In more detail, the graph of  FIG.  8    is a graph illustrating the transmittance when the second refractive layer  720  including both a dye and a pigment includes FDB-002™ (Yamada Kagaku Kogyo Co., Ltd.) and NEC594™ (Ukseung Chemicals) as the dye, and pigment yellow 185 (C.I Pigment Yellow 185) as the pigment  900 . 
     As shown in  FIG.  8   , the second refractive layer  720  of the comparative example absorbs light in a first wavelength range of 350 nm to 430 nm and a third wavelength range of 575 nm to 605 nm. Comparing the graphs of  FIGS.  6  and  8   , the organic encapsulation layer  420  of the display apparatus  1  according to an embodiment of the present disclosure and the second refractive layer  720  of the display apparatus according to the comparative example have a difference in light absorbance in a wavelength area of 380 nm to 480 nm. However, as shown in  FIG.  7   , because the second refractive layer  720  of the display apparatus  1  according to an embodiment absorbs light in the wavelength area of 380 nm to 480 nm, the light absorbance in the 380 nm to 480 nm wavelength area of the display apparatus  1  according to an embodiment having an organic encapsulation layer including a dye and a second refractive layer including a pigment is the same as or similar to the light absorbance in the 380 nm to 480 nm wavelength area of the display apparatus according to the comparative example. Therefore, the display apparatus  1  according to an embodiment having the organic encapsulation layer including a dye and the second refractive layer including a pigment has the same or similar external light reflectance to that of the display apparatus according to the comparative example in which the second refractive layer  720  includes both the dye and the pigment. 
     According to one or more embodiments of the present disclosure as described above, a display apparatus capable of reducing contamination between the layers thereof may be implemented. However, the spirit and scope of the present disclosure is not limited thereto. 
     Although some embodiments have been described, those skilled in the art will readily appreciate that various modifications are possible in the embodiments without departing from the spirit and scope of the present disclosure. It will be understood that descriptions of features or aspects within each embodiment should typically be considered as available for other similar features or aspects in other embodiments, unless otherwise described. Thus, as would be apparent to one of ordinary skill in the art, features, characteristics, and/or elements described in connection with a particular embodiment may be used singly or in combination with features, characteristics, and/or elements described in connection with other embodiments unless otherwise specifically indicated. Therefore, it is to be understood that the foregoing is illustrative of various example embodiments and is not to be construed as limited to the specific embodiments disclosed herein, and that various modifications to the disclosed embodiments, as well as other example embodiments, are intended to be included within the spirit and scope of the present disclosure as defined in the appended claims, and their equivalents.