Patent Publication Number: US-2023165100-A1

Title: Display apparatus

Description:
CROSS-REFERENCE TO RELATED APPLICATION 
     This application claims priority to, and the benefit of, Korean Patent Application No. 10-2021-0160706, filed on Nov. 19, 2021, in the Korean Intellectual Property Office, the disclosure of which is incorporated by reference herein in its entirety. 
     BACKGROUND 
       1 . Field 
     One or more embodiments relate to display apparatuses having an extended display area to display an image even in an area where components that are electronic elements are arranged. 
       2 . Description of the Related Art 
     Recently, uses of display apparatuses have been diversified. Furthermore, as the thickness and the weight of a display apparatus decrease, the scope of a use thereof has expanded. 
     As display apparatuses are variously used, there may be various methods to design the shape of a display apparatus. Also, the number of functions to be grafted or linked to display apparatuses have increased. 
     SUMMARY 
     One or more embodiments include display apparatuses having an extended display area to display an image even in an area where components including electronic elements are arranged. However, such an aspect is merely an example, and the scope of the present disclosure is not limited thereby. 
     Additional aspects 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 practice of the presented embodiments of the disclosure. 
     According to an aspect of the disclosure, a display apparatus includes a substrate including a first area and a second area, auxiliary pixels in the first area, and including first auxiliary pixels, respective ones of which being along a first line, and second auxiliary pixels, respective ones of which being arranged along a second line that is parallel to the first line, and third auxiliary pixels, respective ones of which being arranged along a third line that is parallel to the first line, and having a same pixel arrangement as the second auxiliary pixels, main pixels in the second area, and a transmissive portion between the auxiliary pixels, wherein a first distance between the first line and the second line at one side of the first line is less than a second distance between the first line and the third line at an other side of the first line. 
     Per unit area, a luminance of the first auxiliary pixels may be greater than a luminance of the second auxiliary pixels or the third auxiliary pixels. 
     The first auxiliary pixels may include second sub-pixels for emitting green light. 
     The second auxiliary pixels and the third auxiliary pixels may include first sub-pixels for emitting red light and third sub-pixels for emitting blue light. 
     The first area may be in contact with the second area, and may include a first boundary portion and a second boundary portion that are substantially symmetrical and substantially parallel to each other, wherein a first interval between corresponding ones of the main pixels and corresponding ones of the second auxiliary pixels that are closest to the first boundary portion is different from a second interval between corresponding ones of the main pixels and corresponding ones of the first auxiliary pixels that are closest to the second boundary portion. 
     The first interval may be greater than the second interval. 
     The display apparatus may further include a component corresponding to the first area. 
     The transmissive portion may be between sub-pixels that are configured to emit light of a same wavelength among the auxiliary pixels. 
     Intervals in a first direction between sub-pixels that are configured to emit light of a same wavelength among the auxiliary pixels may be substantially equal. 
     According to another aspect of the disclosure, a display apparatus includes a substrate including a first area and a second area, auxiliary pixels in the first area, main pixels in the second area, a transmissive portion between the auxiliary pixels, and a first boundary portion and a second boundary portion, which are substantially symmetrical and substantially parallel to each other, as respective boundary portions contacting the first area and the second area, wherein a first interval between respective ones of the main pixels and respective ones of auxiliary pixels that are closest to the first boundary portion is different from a second interval between others of the main pixels and others of the auxiliary pixels that are closest to the second boundary portion. 
     The auxiliary pixels may be in n rows and m columns, and are entirely shifted in the second area in a first direction from a first row toward an n-th row, and/or in a second direction from a first column toward an m-th column. 
     A distance in which the auxiliary pixels are shifted in the first direction may be different from a distance in which the auxiliary pixels are shifted in the second direction. 
     The auxiliary pixels may include first auxiliary pixels in the first row and second auxiliary pixels in the n-th row, wherein the first auxiliary pixels and the second auxiliary pixels are configured to emit light of different wavelengths. 
     The first auxiliary pixels may be configured to emit green light, and the second auxiliary pixels may be configured to emit blue or red light. 
     The first interval may be greater than the second interval. 
     The display apparatus may further include a component corresponding to the first area. 
     According to another aspect of the disclosure, a display apparatus includes a substrate including a first area and a second area, auxiliary pixels in the first area and including first sub-pixels, second sub-pixels, and third sub-pixels, the first sub-pixels, the second sub-pixels, and the third sub-pixels configured to respectively emit light of different wavelengths, main pixels in the second area, a transmissive portion between the auxiliary pixels, and a first boundary portion and a second boundary portion that are substantially symmetrical and substantially parallel to each other, and contacting the first area and the second area, wherein, per unit area, a luminance of the second sub-pixels is greater than a luminance of the first sub-pixels and the third sub-pixels, and wherein, in the first area, the first sub-pixels are shifted in a first direction from the second boundary portion to the first boundary portion. 
     The first sub-pixels and the second sub-pixels may be alternately arranged in the second boundary portion, wherein the second sub-pixels and the third sub-pixels are alternately arranged in the first boundary portion. 
     The second sub-pixels may be configured to emit green light. 
     The first sub-pixels may be configured to emit red light, and the third sub-pixels may be configured emit blue light. 
     The display apparatus may further include a component corresponding to the first area. 
     An arrangement of respective ones of the main pixels closest to the first boundary portion may be the same as an arrangement of respective ones of the auxiliary pixels closest to the second boundary portion. 
     The respective ones of the main pixels closest to the first boundary portion and the respective ones of the auxiliary pixels closest to the second boundary portion may be configured to emit light of a same color. 
     The first area may include a third boundary portion and a fourth boundary portion in contact with the second area, and substantially symmetrical and substantially parallel to each other in a second direction crossing the first direction, wherein an arrangement of corresponding ones of the main pixels closest to the third boundary portion is the same as an arrangement of corresponding ones of the auxiliary pixels closest to the fourth boundary portion. 
     The corresponding ones of the main pixels closest to the third boundary portion and the corresponding ones of the auxiliary pixels closest to the fourth boundary portion may be configured to emit light of a same color. 
     Aspects other than those described above will become apparent from the following drawings, claims, and detailed description of the disclosure 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       The above and other aspects of certain embodiments of the disclosure will be more apparent from the following description taken in conjunction with the accompanying drawings, in which: 
         FIG.  1    is a schematic perspective view of a display apparatus according to one or more embodiments; 
         FIG.  2    is a plan view of part of a display area, according to one or more embodiments; 
         FIG.  3    is an enlarged plan view of a component area and a main display area therearound of the display area of  FIG.  2   ; 
         FIG.  4    is a schematic cross-sectional view showing part of a display apparatus according to one or more embodiments; 
         FIG.  5    is a schematic plan view of a display panel that may be included in the display apparatus of  FIG.  4   ; 
         FIG.  6    is a schematic cross-sectional view showing part of a display apparatus according to one or more other embodiments; 
         FIG.  7    is a schematic plan view of a display panel that may be included in the display apparatus of  FIG.  6   ; 
         FIGS.  8 A and  8 B  are schematic plan views showing partial areas of a display panel, according to one or more embodiments; 
         FIGS.  9 A and  9 B  are schematic cross-sectional views showing partial areas of a display panel, according to one or more embodiments; 
         FIGS.  10  and  11    are schematic plan views showing parts of a display area, according to one or more embodiments; and 
         FIGS.  12  to  15    are schematic plan views showing various pixel arrangements in a display area of a display apparatus, according to embodiments. 
     
    
    
     DETAILED DESCRIPTION 
     Reference will now be made in detail to embodiments, examples of which are illustrated in the accompanying drawings, wherein like reference numerals refer to like elements throughout. In this regard, the present embodiments may have different forms and should not be construed as being limited to the descriptions set forth herein. Accordingly, the embodiments are merely described below, by referring to the figures, to explain aspects of the present description. As used herein, the term “and/or” includes any and all combinations of one or more of the associated listed items. Throughout the disclosure, the expression “at least one of a, b or 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. 
     Various modifications may be applied to the present embodiments, and particular embodiments will be illustrated in the drawings and described in the detailed description section. The effect and features of the present embodiments, and a method to achieve the same, will be clearer referring to the detailed descriptions below with the drawings. However, the present embodiments may be implemented in various forms, not by being limited to the embodiments presented below. 
     Hereinafter, embodiments will be described in detail with reference to the accompanying drawings, and in the description with reference to the drawings, the same or corresponding constituents are indicated by the same reference numerals and redundant descriptions thereof are omitted. 
     It will be understood that although the terms “first,” “second,” etc. may be used herein to describe various components, these components should not be limited by these terms. These components are only used to distinguish one component from another. 
     As used herein, the singular forms “a,” “an” and “the” are intended to include the plural forms as well, unless the context clearly indicates otherwise. 
     It will be further understood that the terms “comprises” and/or “comprising” used herein specify the presence of stated features or components, but do not preclude the presence or addition of one or more other features or components. 
     In the specification, it will be understood that when a layer, region, or component is referred to as being “formed on” another layer, region, or component, it can be directly or indirectly formed on the other layer, region, or component. That is, for example, intervening layers, regions, or components may be present. 
     In the specification, it will be understood that when a layer, region, or component is referred to as being “connected to” another layer, region, or component, it can be directly connected to the other layer, region, or component or indirectly connected to the other layer, region, or component via intervening layers, regions, or components. For example, in the specification, when a layer, region, or component is referred to as being electrically connected to another layer, region, or component, it can be directly electrically connected to the other layer, region, or component or indirectly electrically connected to the other layer, region, or component via intervening layers, regions, or components. 
     In the specification, the expression such as “A and/or B” may include A, B, or A and B. Furthermore, the expression such as “at least one of A and B” may include A, B, or A and B. 
     In the specification, 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 one another, or may represent different directions that are not perpendicular to one another. 
     In the specification, when a certain embodiment may be implemented differently, a specific process order may be performed differently from the described order. For example, two consecutively described processes may be performed substantially at the same time or performed in an order opposite to the described order. 
     Sizes of components in the drawings may be exaggerated for convenience of explanation. For example, since sizes and thicknesses of components in the drawings are arbitrarily illustrated for convenience of explanation, the following embodiments are not limited thereto. 
       FIG.  1    is a schematic perspective view of a display apparatus  1  according to one or more embodiments. 
     Referring to  FIG.  1   , the display apparatus  1  may include a display area DA, and a peripheral area NDA outside the display area DA. The display area DA may include a first area DA 1  that is a component area, and a second area DA 2  that is a main display area at least partially surrounding the first area DA 1 . The first area DA 1  displays an auxiliary image, and the second area DA 2  displays a main image. The first area DA 1  and the second area DA 2  may individually display different images, or may display an image together. The peripheral area NDA may be a kind of a non-display area where no display element is arranged. The display area DA may be entirely surrounded by the peripheral area NDA. 
     The second area DA 2  may be located to surround at least part of a singular first area DA 1 . As an example,  FIG.  1    illustrates that the second area DA 2  entirely surrounds the singular first area DA 1 . In one or more other embodiments, the display apparatus  1  may have two or more first areas DA 1 , and the shape and size of a plurality of first areas DA 1  may be different from each other. When viewed from a direction approximately perpendicular to an upper surface of the display apparatus  1 , the first area DA 1  may have various shapes, such as a circle, an oval, a polygon, such as a rectangle and the like, a star, a diamond, etc. 
       FIG.  1    illustrates that, when viewed from a direction approximately perpendicular to the upper surface of the display apparatus  1 , the first area DA 1  is located at the upper center of, or generally above the center of, the second area DA 2  having an approximately rectangular shape. However, in some embodiments, the first area DA 1  may be located at one side, for example, at the upper right side or the upper left side, of the second area DA 2  having a rectangular shape. For example, the first area DA 1  having a circular shape may be located in the second area DA 2 , or the first area DA 1  having a rectangular bar shape may be located at one side of the second area DA 2 . 
     The display apparatus  1  may provide an image by using a plurality of main sub-pixels Pm arranged in the second area DA 2 , and a plurality of auxiliary sub-pixels Pa arranged in the first area DA 1 . 
     In the first area DA 1 , a component  20  that is an electronic element may be arranged under a display panel corresponding to the first area DA 1 , as described below with reference to  FIGS.  4  or  6   . 
     Referring to  FIGS.  4  or  6   , the component  20  may be an electronic element that uses light or sound. For example, the electronic element may include a sensor for measuring a distance, for example, a proximity sensor, a sensor for recognizing part of the body of a user, for example, a fingerprint, an iris, a face, and the like, a compact lamp for outputting light, an image sensor for capturing an image, for example, a camera, and the like. An electronic element using light may use light in various wavelength ranges, for example, visible light, infrared light, ultraviolet light, and the like. An electronic element using sound may uses ultrasound or sound of a different frequency range. In some embodiments, the component  20  may include subcomponents, such as a light-emitting portion and a light-receiving portion together. The light-emitting portion and the light-receiving portion may have an integrated structure or a physically separated structure, and a pair of the light-emitting portion and the light-receiving portion may constitute a singular component  20 . To reduce a limitation on the function of the component  20 , the first area DA 1  may include a transmissive area TA through which light or/and sound and the like that is output from the component  20  to the outside or proceeds from the outside to the component  20  may transmit. 
     In a display panel according to one or more embodiments and a display apparatus including the display panel, when light transmits through the first area DA 1 , light transmittance maybe about 10% or more, for example, about 40% or more, about 25% or more, about 50% or more, about 85% or more, or about 90% or more. 
     A plurality of auxiliary sub-pixels Pa may be arranged in the first area DA 1 . The auxiliary sub-pixels Pa may emit light to provide a certain image. An image displayed in the first area DA 1  is an auxiliary image, and may have a resolution that is less than that of an image displayed in the second area DA 2 . In other words, the first area DA 1  includes the transmissive area TA through which light and sound may transmit, and when no sub-pixel is arranged in the transmissive area TA, the number of the auxiliary sub-pixels Pa to be arranged per unit area in the first area DA 1  may be less than the number of the main sub-pixels Pm to be arranged per unit area in the second area DA 2 . 
     In the following description, an organic light-emitting display apparatus is described as an example of the display apparatus  1  according to one or more embodiments, but the disclosure is not limited thereto. In one or more other embodiments, the display apparatus  1  may include display an apparatus such as an inorganic light-emitting display apparatus, an inorganic EL display apparatus, or a quantum dot light-emitting display apparatus. For example, an emission layer of a display element provided in the display apparatus  1  may include an organic material, an inorganic material, a quantum dot, an organic material and a quantum dot, or an inorganic material and a quantum dot. 
       FIG.  2    is a plan view showing part of the display area DA, according to one or more embodiments.  FIG.  3    is an enlarged plan view of the component area and the main display area therearound of the display area DA of  FIG.  2   . 
     Referring to  FIG.  2   , the first area DA 1  is provided as an approximate rectangle, and four sides thereof may be in contact with the second area DA 2 . In  FIG.  2   , the first area DA 1  and the second area DA 2  may be in contact with each other in a first boundary portion BP 1 , a second boundary portion BP 2 , a third boundary portion BP 3 , and a fourth boundary portion BP 4 . In this state, the first boundary portion BP 1  and the second boundary portion BP 2 , and the third boundary portion BP 3  and the fourth boundary portion BP 4 , may be respectively provided symmetrically to each other. The first boundary portion BP 1  and the second boundary portion BP 2  may be provided parallel to each other in an x-axis direction, and the third boundary portion BP 3  and the fourth boundary portion BP 4  may be provided parallel to each other in a y-axis direction. 
     In the display apparatus  1  according to one or more embodiments, in the first to fourth boundary portions BP 1 , BP 2 , BP 3 , and BP 4  that the first area DA 1  and the second area DA 2  contact, an interval between respective main sub-pixels Pm and auxiliary sub-pixels Pa arranged on at least one boundary portion may be greater than an interval between respective main sub-pixels Pm and auxiliary sub-pixels Pa arranged on another boundary portion that is symmetrical to the at least one boundary portion. The auxiliary sub-pixels Pa arranged corresponding to the first to fourth boundary portions BP 1 , BP 2 , BP 3 , and BP 4  have a luminance difference. To reduce the luminance difference, the interval between the main sub-pixels Pm and the auxiliary sub-pixels Pa arranged on at least one boundary portion, and the interval between the main sub-pixels Pm and the auxiliary sub-pixels Pa arranged on another boundary portion that is symmetrical to the at least one boundary portion, are different from each other so that the luminance difference in an edge portion of the first area DA 1  may be reduced. 
     In the present specification, the interval between respective main sub-pixels Pm and auxiliary sub-pixels Pa arranged on a boundary portion is based on the main sub-pixels Pm and the auxiliary sub-pixels Pa that are arranged closest to each other with respect to the boundary portion, and may substantially mean intervals d1, d2, d3, and d4 (see  FIG.  3   ) between respective main sub-pixels Pm and auxiliary sub-pixels Pa, or intervals d1′, d2′, d3′, and d4′ (see  FIG.  3   ) between the centers of respective main sub-pixels Pm and auxiliary sub-pixels Pa. Furthermore, in the case when the size or the respective shape of main sub-pixels Pm and auxiliary sub-pixels Pa arranged on a boundary portion are different from each other, the interval may mean an average interval therebetween. 
     In one or more embodiments, in the display apparatus  1  of  FIG.  3   , a first interval d1 between the main sub-pixels Pm and the auxiliary sub-pixels Pa arranged on the first boundary portion BP 1  may be different from a second interval d2 between the main sub-pixels Pm and the auxiliary sub-pixels Pa arranged on the second boundary portion BP 2  that is symmetrical to the first boundary portion BP 1 . For example, the first interval d1 may be greater than the second interval d2. In other words, the auxiliary sub-pixels Pa arranged in the first area DA 1  may be entirely moved in a +y direction or a -y direction. In  FIG.  3   , a third interval d3 and a fourth interval d4 between the main sub-pixels Pm and the auxiliary sub-pixels Pa arranged on each of the third boundary portion BP 3  and the fourth boundary portion BP 4  provided symmetrically to each other are illustrated to be the same, but the disclosure is not limited thereto. 
     In one or more other embodiments, the third interval d3 between the main sub-pixels Pm and the auxiliary sub-pixels Pa arranged on the third boundary portion BP 3  may be different from the fourth interval d4 between the main sub-pixels Pm and the auxiliary sub-pixels Pa arranged on the fourth boundary portion BP 4  that is symmetrical to the third boundary portion BP 3 . In other words, the auxiliary sub-pixels Pa arranged in the first area DA 1  may be entirely moved in a +x direction or a -x direction. In this case, the first interval d1 and the second interval d2 may be the same or different from each other. 
       FIG.  4    is a schematic cross-sectional view showing part of the display apparatus  1  according to one or more embodiments.  FIG.  5    is a schematic plan view of a display panel that may be included in the display apparatus  1  of  FIG.  4   . 
     Referring to  FIG.  4   , the display apparatus  1  may include a display panel  10  and the component  20  that overlaps the display panel  10 . In some embodiments, a cover window for protecting the display panel  10  may be further provided above the display panel  10 . 
     The display panel  10  may include a substrate  100 , a display layer DISL on the substrate  100 , a touchscreen layer TSL, an optical functional layer OFL, and a panel protection member PP below the substrate  100 . 
     The display layer DISL may include a circuit layer PCL including thin film transistors TFTm and TFTa, a display element layer EDL including emission elements (EDm and EDa) that are display elements, and a sealing member ENM, such as a thin film encapsulation layer TFE or a sealing substrate. Insulating layers IL and IL’ may be arranged between the substrate  100  and the display element layer EDL in the display layer DISL. 
     The substrate  100  may include an insulating material, such as glass, quartz, polymer resin, and the like. The substrate  100  may include a rigid substrate or a flexible substrate capable of bending, folding, rolling, and the like. 
     A main emission element EDm, and a main pixel circuit PCm connected to the main emission element EDm, may be arranged in the second area DA 2  of the display panel  10 . The main pixel circuit PCm may include at least one thin film transistor TFTm, and may control an operation of the main emission element EDm. The main sub-pixels Pm may be implemented through the light-emission of the main emission element EDm. 
     As an auxiliary emission element EDa is arranged in the first area DA 1  of the display panel  10 , the auxiliary sub-pixels Pa may be implemented. In one or more embodiments, an auxiliary pixel circuit PCa for driving the auxiliary emission element EDa may be arranged not in the first area DA 1 , but instead in the peripheral area NDA that is a non-display area. In one or more other embodiments, the auxiliary pixel circuit PCa may be arranged in various ways, for example, in part of the second area DA 2 , between the second area DA 2  and the first area DA 1 , or the like. In other words, the auxiliary pixel circuit PCa may be arranged not to overlap the auxiliary emission element EDa. 
     The auxiliary pixel circuit PCa may include at least one thin film transistor TFTa, and may be electrically connected to the auxiliary emission element EDa via a connection wiring TWL. The connection wiring TWL may include a transparent conductive material. The auxiliary pixel circuit PCa may control an operation of the auxiliary emission element EDa. The auxiliary sub-pixels Pa may be implemented through the light-emission of the auxiliary emission element EDa. 
     An area of the first area DA 1  where the auxiliary emission element EDa is not arranged may be defined as the transmissive area TA. 
     The transmissive area TA may be an area through which either light/signal emitted from the component  20  arranged corresponding to the first area DA 1 , or light/signal incident on the component  20 , is transmitted. The transmissive area TA may be alternately arranged with the auxiliary emission element EDa (or, an area where a plurality of auxiliary emission elements EDa are arranged) in the first area DA 1 . The connection wiring TWL connecting the auxiliary pixel circuit PCa and the auxiliary emission element EDa may be arranged in the transmissive area TA. The connection wiring TWL may include a transparent conductive material having relatively high transmittance, and even when the connection wiring TWL is arranged in the transmissive area TA, the transmittance of the transmissive area TA may be secured. In one or more embodiments, as the auxiliary pixel circuit PCa is not arranged in the first area DA 1 , the area of the transmissive area TA may be easily expanded, and light transmittance may be improved. 
     The display element layer EDL may be covered by the thin film encapsulation layer TFE, or by the sealing substrate, as illustrated in  FIG.  4   . In one or more embodiments, the thin film encapsulation layer TFE may include at least one inorganic encapsulation layer and at least one organic encapsulation layer, as illustrated in  FIG.  4   . For example, the thin film encapsulation layer TFE may include first and second inorganic encapsulation layers  131  and  133 , and an organic encapsulation layer  132  therebetween. 
     The first inorganic encapsulation layer  131 , the organic encapsulation layer  132 , and the second inorganic encapsulation layer  133  may be integrally formed to cover the second area DA 2  and the first area DA 1 . 
     When the display element layer EDL is sealed by a sealing substrate, in some embodiments, the sealing substrate may face the substrate  100  with the display element layer EDL interposed therebetween. A gap may be present between the sealing substrate and the display element layer EDL. The sealing substrate may include glass. A sealant formed of frit and the like is arranged between the substrate  100  and the sealing substrate, and the sealant may be arranged in the above-described peripheral area NDA. The sealant arranged in the peripheral area NDA may surround the display area DA to reduce or prevent infiltration of moisture through a side surface. 
     The touchscreen layer TSL may acquire coordinates information according to an external input, for example, a touch event. The touchscreen layer TSL may include a touch electrode and touch wirings connected to the touch electrode. The touchscreen layer TSL may detect an external input by a self-capacitance method or a mutual capacitance method. 
     The touchscreen layer TSL may be formed on the thin film encapsulation layer TFE. Alternatively, the touchscreen layer TSL may be formed separately on a touch substrate and then may be coupled to the thin film encapsulation layer TFE through an adhesive layer, such as an optically clear adhesive (OCA). In one or more embodiments, the touchscreen layer TSL may be formed directly on the thin film encapsulation layer TFE, and in this case, the adhesive layer may not be arranged between the touchscreen layer TSL and the thin film encapsulation layer TFE. 
     The optical functional layer OFL may include an antireflective layer. The antireflective layer may reduce reflectivity of light (external light) input to the display apparatus  1  from the outside. 
     In one or more embodiments, the optical functional layer OFL may include a polarization film. The optical functional layer OFL may include an opening OFL_OP corresponding to the transmissive area TA. Accordingly, light transmittance of the transmissive area TA may be remarkably improved. The opening OFL_OP may be filled with a transparent material, such as light transparent resin (OCR, optically clear resin). In one or more other embodiments, the optical functional layer OFL may be provided as a filter plate including a black matrix and color filters. 
     The panel protection member PP may be attached on a lower surface of the substrate  100 , and may support and protect the substrate  100 . The panel protection member PP may include, or define, an opening PP_OP corresponding to the first area DA 1 . As the panel protection member PP includes/defines the opening PP_OP, the light transmittance of the first area DA 1  may be improved. A panel protection member PP may include polyethylene terephthalate or polyimide. 
     The area of the first area DA 1  may be greater than an area where the component  20  is arranged. Accordingly, the area of the opening PP_OP in the panel protection member PP may not match the area of the first area DA 1 .  FIG.  4    illustrates that the component  20  is arranged at one side of the display panel  10  apart from the display panel  10 , but at least part of the component  20  may be inserted in the opening PP_OP of the panel protection member PP. 
     Furthermore, a plurality of components  20  may be arranged in the first area DA 1 . The components  20  may have different functions. For example, the components  20  may include at least two of a camera (imaging device), a solar cell, a flash, a proximity sensor, an illuminance sensor, and an iris sensor. 
       FIG.  4    illustrates a case of one first area DA 1 , but a plurality of first areas DA 1  may be provided as the first area DA 1 . In this case, the first areas DA 1  may be arranged apart from each other. For example, while a first camera may be arranged corresponding to one of the first areas DA 1 , a second camera may be arranged corresponding to another of the first areas DA 1 . Alternatively, while a camera may be arranged corresponding to one of the first areas DA 1 , an infrared sensor may be arranged corresponding to another of the first areas DA 1 . The shapes and the sizes of the first areas DA 1  may be different from each other. 
     Referring to  FIG.  5   , various constituent elements constituting the display panel  10  are arranged above the substrate  100 . 
     The main sub-pixels Pm may be arranged in the second area DA 2 . Each of the main sub-pixels Pm may be implemented, as a light-emitting device, by a display element such as an organic light-emitting diode OLED. The main pixel circuit PCm for driving the main sub-pixels Pm may be arranged in the second area DA 2 , and the main pixel circuit PCm may be arranged to overlap the main sub-pixels Pm. Each of the main sub-pixels Pm may emit, for example, red, green, blue, or white light. The second area DA 2  may be covered by the sealing member ENM to be protected from external air, moisture, or the like. 
     The first area DA 1  may be located at one side of the second area DA 2 , or arranged inside the display area DA to be surrounded by the second area DA 2 , as described above. The auxiliary sub-pixels Pa are arranged in the first area DA 1 . Each of the auxiliary sub-pixels Pa may be implemented as a light-emitting device using a display element, such as the organic light-emitting diode OLED. Each of the auxiliary sub-pixels Pa may emit, for example, red, green, blue, or white light. The first area DA 1  is covered by the sealing member ENM to be protected from external air, moisture, or the like. 
     The auxiliary pixel circuit PCa for driving the auxiliary sub-pixels Pa may be arranged in the peripheral area NDA adjacent to the first area DA 1 . For example, when the first area DA 1  is arranged at an upper area of the display area DA, as illustrated in  FIG.  5   , the auxiliary pixel circuit PCa may be arranged in an upper side of the peripheral area NDA. The auxiliary pixel circuit PCa and the display element implementing the auxiliary sub-pixels Pa may be connected to each other by the connection wiring TWL extending in one direction, for example, the y direction. 
     The first area DA 1  may have the transmissive area TA. The transmissive area TA may be arranged to surround the auxiliary sub-pixels Pa. Alternatively, the transmissive area TA may be arranged in the form of a lattice with the auxiliary sub-pixels Pa. 
     As the first area DA 1  has the transmissive area TA, the resolution of the first area DA 1  may be less than the resolution of the second area DA 2 . For example, the resolution of the first area DA 1  may be about ½, about ⅜, about ⅓, about ¼, about 2/9, about ⅛, about ⅑, about 1/16, etc. times the resolution of the second area DA 2 . For example, the resolution of the second area DA 2  may be about 400 ppi or more, and the resolution of the first area DA 1  may be about 200 ppi or about 100 ppi. 
     Each of the pixel circuits PCm and PCa for driving the sub-pixels Pm and Pa may be electrically connected to outer circuits arranged in the peripheral area NDA. A first scan driving circuit SDR1, a second scan driving circuit SDR2, a terminal portion PAD, a driving voltage supply line  11 , and a common voltage supply line  13  may be arranged in the peripheral area NDA. 
     The first scan driving circuit SDR1 may apply, through a scan line SL, a scan signal to the main pixel circuit PCm for driving the main sub-pixels Pm. Furthermore, the first scan driving circuit SDR1 may apply a light-emitting control signal to each pixel circuit through a light-emitting control line EL. The second scan driving circuit SDR2 may be arranged symmetrical to the first scan driving circuit SDR1 with respect to the second area DA 2 . Some of the main pixel circuit PCm of the main sub-pixels Pm in the second area DA 2  may be electrically connected to the first scan driving circuit SDR1, and the other may be electrically connected to the second scan driving circuit SDR2. 
     The terminal portion PAD may be arranged at one side of the substrate  100 . The terminal portion PAD is not covered by insulating layers IL and IL’ to be exposed and is connected to a display circuit board  30 . A display driver  32  may be arranged above the display circuit board  30 . 
     The display driver  32  may generate a control signal that is transmitted to the first scan driving circuit SDR1 and the second scan driving circuit SDR2. The display driver  32  may generate a data signal, and the generated data signal may be transmitted to the main pixel circuit PCm through a fan-out wiring FW, and a main data line DL/DLm connected to the fan-out wiring FW. 
     The display driver  32  may supply a driving voltage ELVDD through the driving voltage supply line  11 , and a common voltage ELVSS through the common voltage supply line  13 . The driving voltage ELVDD is applied to the pixel circuits PCm and PCa of the sub-pixels Pm and Pa through a driving voltage line PL connected to the driving voltage supply line  11 , and the common voltage ELVSS may be applied a counter electrode of the display element through the common voltage supply line  13 . 
     The driving voltage supply line  11  may extend in the x direction under the second area DA 2 . The common voltage supply line  13  has a loop shape with one open side to partially surround the second area DA 2 . 
       FIG.  6    is a schematic cross-sectional view showing part of a display apparatus according to one or more other embodiments.  FIG.  7    is a schematic plan view of a display panel that may be included in the display apparatus of  FIG.  6   . 
     The display apparatus of  FIGS.  6  and  7   , there is a difference in that the auxiliary pixel circuit PCa for driving the auxiliary sub-pixels Pa in the first area DA 1  is located not in the peripheral area NDA, but instead is located in a middle area MA between the second area DA 2  and the first area DA 1 . The auxiliary pixel circuit PCa may be arranged in middle area MA adjacent to the first area DA 1 . In the following description, a difference from the above-described embodiments corresponding to  FIGS.  4  and  5    is mainly described. 
     Referring to  FIGS.  6  and  7   , the display area DA may include the first area DA 1  that is a component area, the second area DA 2  that is a main display area, and the middle area MA located in at least a partial area between the first area DA 1  and the second area DA 2 . 
     The first area DA 1  and the middle area MA are arranged in the display area DA, and at least partially surrounded by the second area DA 2 . A plurality of first and second auxiliary sub-pixels P a   1  and P a   2  may be arranged in the first area DA 1  and the middle area MA. Each of the auxiliary sub-pixels P a   1  and P a   2  may be implemented, as a light-emitting device, by a display element such as the organic light-emitting diode OLED. Each auxiliary sub-pixel Pa may emit, for example, red, green, blue, or white light. 
     The first auxiliary sub-pixel P a   1  may be implemented in the first area DA 1 , and the second auxiliary sub-pixel P a   2  may be implemented in the middle area MA. This means that the first auxiliary sub-pixel P a   1  substantially emits light in the first area DA 1 , and the second auxiliary sub-pixel P a   2  substantially emits light in the middle area MA. 
     A first auxiliary pixel circuit PC a   1  for driving the first auxiliary sub-pixel P a   1 , and a second auxiliary pixel circuit PC a   2  for driving the second auxiliary sub-pixel P a   2 , may both be arranged in the middle area MA. In this case, as a first auxiliary display element ED a   1  for implementing the first auxiliary sub-pixel P a   1  is arranged in the first area DA 1 , and the first auxiliary pixel circuit PC a   1  is arranged in the middle area MA, the first auxiliary display element ED a   1  and first the auxiliary pixel circuit PCa may be connected to each other by the connection wiring TWL. 
     As illustrated in  FIG.  6   , a display layer DPL may include the circuit layer PCL including thin film transistors TFTm, TFTa1, and TFTa2, the display element layer EDL including display elements EDm, ED a   1 , and ED a   2  that are light-emitting devices, and the thin film encapsulation layer TFE or the sealing member ENM, such as a sealing substrate. The insulating layers IL and IL’ may be arranged between the substrate  100  and the display element layer EDL and in the display layer DPL. For example, the display elements EDm, ED a   1 , and ED a   2  may be organic light-emitting diodes. 
     The first auxiliary display element ED a   1  is arranged in the first area DA 1  of the display panel  10  to implement the first auxiliary sub-pixel P a   1 . In one or more embodiments, the first auxiliary pixel circuit PC a   1  may be arranged not to overlap the first auxiliary display element ED a   1 . In other words, the first auxiliary pixel circuit PC a   1  for driving the first auxiliary display element ED a   1  may be arranged in the middle area MA between the second area DA 2  and the first area DA 1 . Alternatively, in one or more other embodiments, the first auxiliary pixel circuit PC a   1  for driving the first auxiliary display element ED a   1  may be arranged in the middle area MA and the peripheral area NDA. 
     The first auxiliary pixel circuit PC a   1  may include at least one first auxiliary thin film transistor TFTa1, and may be electrically connected to first the auxiliary emission element EDa through the connection wiring TWL. The connection wiring TWL may include a transparent conductive material. The first auxiliary pixel circuit PC a   1  may control an operation of the first auxiliary display element ED a   1 . The first auxiliary sub-pixel P a   1  may be implemented through the light-emission of the first auxiliary display element ED a   1 . 
     An area of the first area DA 1  where the first auxiliary display element ED a   1  is not arranged may be defined as the transmissive area TA. The transmissive area TA may be an area through which light/signal emitted from a component  40  arranged corresponding to the first area DA 1  or light/signal incident on the component  40  is transmitted. 
     The connection wiring TWL connecting the first auxiliary pixel circuit PC a   1  and the first auxiliary display element ED a   1  may be arranged in the transmissive area TA. The connection wiring TWL may include a transparent conductive material having relatively high transmittance, and even when the connection wiring TWL is arranged in the transmissive area TA, the transmittance of the transmissive area TA may be secured. In one or more embodiments, as the auxiliary pixel circuit PCa is not arranged in the first area DA 1 , the area of the transmissive area TA may be easily expanded, and light transmittance may be improved. 
     As a second auxiliary display element ED a   2  and the second auxiliary pixel circuit PC a   2  connected thereto are arranged in the middle area MA of the display panel  10 , the second auxiliary sub-pixel P a   2  may be implemented. The first auxiliary pixel circuit PC a   1  and the second auxiliary pixel circuit PC a   2  arranged in the middle area MA may be arranged alternately adjacent to each other. 
     As illustrated in  FIG.  6   , a bottom metal layer BML may be arranged below the first and second auxiliary pixel circuits PC a   1  and PC a   2  of the middle area MA. The bottom metal layer BML may be arranged overlapping the first and second auxiliary pixel circuits PC a   1  and PC a   2  to protect the same. In one or more embodiments, the bottom metal layer BML may be arranged between the substrate  100  corresponding to the middle area MA and the first and second auxiliary pixel circuits PC a   1  and PC a   2 , to overlap the first and second auxiliary pixel circuits PC a   1  and PC a   2 . The bottom metal layer BML may block or reduce the external light from reaching the first and second auxiliary pixel circuits PC a   1  and PC a   2 . In one or more other embodiments, the bottom metal layer BML is formed to correspond to the entire display area DA, and may be provided to include a lower hole corresponding to the first area DA 1 . The bottom metal layer BML may be applied to the above-described embodiments corresponding to  FIG.  4   . In one or more other embodiments, the bottom metal layer BML may be omitted. 
     As illustrated in  FIG.  7   , the pixel circuits PCm, PC a   1 , and PC a   2  for respectively driving the sub-pixels Pm, P a   1 , and P a   2  in the display area DA may be respectively electrically connected to external circuits arranged in the peripheral area NDA. The first scan driving circuit SDR1, the second scan driving circuit SDR2, the terminal portion PAD, the driving voltage supply line  11 , and the common voltage supply line  13  may be arranged in the peripheral area NDA. 
       FIG.  8 A  is a schematic plan view showing a partial area of the display panel  10 , according to one or more embodiments. 
     In detail,  FIG.  8 A  illustrates the first area DA 1 , the second area DA 2  therearound, and a pixel circuit portion PCP in the peripheral area NDA.  FIG.  8 A  may correspond to part of  FIG.  5    that is described above. 
     Referring to  FIG.  8 A , the main sub-pixels Pm may be arranged in the second area DA 2 . In the present specification, a main sub-pixels Pm may be a minimum unit for implementing an image as a sub-pixel, and may mean a light-emitting area that emits light by a display element. When the organic light-emitting diode OLED is employed as a display element, the light-emitting area may be defined by an opening of a pixel defining layer, which is described below. Each of the main sub-pixels Pm may emit light of light of any one of red, green, blue and white. 
     In some embodiments, the main sub-pixels Pm arranged in the second area DA 2  may include a first sub-pixel Pmr, a second sub-pixel Pmg, and a third sub-pixel Pmb. The first sub-pixel Pmr, the second sub-pixel Pmg, and the third sub-pixel Pmb may implement red, green, and blue light, respectively. The main sub-pixels Pm may be arranged in a PENTILE™ structure (e.g., PENTILE™ matrix structure, PENTILE™ being a registered trademark of Samsung Display Co., Ltd., Republic of Korea). Through the above pixel arrangement structure, by employing rendering driving of sharing adjacent pixels to express a color, a high resolution may be implemented with a small number of pixels. 
       FIG.  8 A  illustrates that the main sub-pixels Pm are arranged in the PENTILE™ matrix structure, but the disclosure is not limited thereto. For example, the main sub-pixels Pm may be arranged in various shapes such as a stripe structure, a mosaic arrangement structure, a delta arrangement structure, and the like. 
     In the second area DA 2 , the main pixel circuits PCm may be arranged overlapping the main sub-pixels Pm, and the main pixel circuits PCm may be arranged in a matrix shape in the x direction and y direction. In the present specification, the main pixel circuit PCm may mean a unit of a pixel circuit for implementing one main sub-pixel Pm. 
     The auxiliary sub-pixels Pa may be arranged in the first area DA 1 . Each of the auxiliary sub-pixels Pa may emit light of any one color of red, green, blue, and white, as a sub-pixel. The auxiliary sub-pixels Pa may include a first sub-pixel Par, a second sub-pixel Pag, and a third sub-pixel Pab, which respectively emit different colors. The first sub-pixel Par, the second sub-pixel Pag, and the third sub-pixel Pab may implement red, green, and blue, respectively. 
     The number per unit area of the auxiliary sub-pixels Pa arranged in the first area DA 1  may be less than the number per unit area of the main sub-pixels Pm arranged in the second area DA 2 . For example, the number of the auxiliary sub-pixels Pa and the number of the main sub-pixels Pm, which are arranged per equal area, may be a ratio of about 1:2, about 1:4, about 1:8, or about 1:9. In other words, the resolution of the first area DA 1  may be about ½, about ¼, about ⅛, or about ⅑ of the resolution of the second area DA 2 .  FIG.  4    illustrates a case in which the resolution of the first area DA 1  is ⅛ of the resolution of the second area DA 2 . 
     The auxiliary sub-pixels Pa arranged in the first area DA 1  may have various shapes. The auxiliary sub-pixels Pa may form a pixel group as some of the auxiliary sub-pixels Pa gather, and may be arranged, in the pixel group, in various shapes such as a PENTILE™ structure, a stripe structure, a mosaic arrangement structure, a delta arrangement structure, and the like. 
     Alternatively, as illustrated in  FIG.  8 A , the auxiliary sub-pixels Pa may be arranged and distributed in the first area DA 1 . In other words, a distance between the auxiliary sub-pixels Pa may be greater than a distance between the main sub-pixels Pm. An area of the first area DA 1 , where the auxiliary sub-pixels Pa are not arranged, may be the transmissive area TA having high light transmittance. 
     The auxiliary sub-pixels Pa arranged in the first area DA 1  may be provided in a rhombic (or rectangular) shape as illustrated in  FIG.  8 A . Alternatively, the auxiliary sub-pixels Pa arranged in the first area DA 1  may be provided in a circular (or oval) shape, as illustrated in  FIG.  8 B . The shape of the auxiliary sub-pixels Pa may mean the shape in a light-emitting area. In other words, the shape of the auxiliary sub-pixels Pa may be defined through an opening of a pixel defining layer  119  of  FIG.  9 A  and the like that is described below. 
     Furthermore, the shape of a second pixel electrode  121 ′ (see  FIG.  9 A ) of each of the auxiliary sub-pixels Pa may not necessarily be similar to the shape of a light-emitting area, but the second pixel electrode  121 ′ of each of the auxiliary sub-pixels Pa may suitably reduce diffraction and scattering of light in a process of transmitting light in the transmissive area TA. Accordingly, in this case, the second pixel electrode  121 ′ of each of the auxiliary sub-pixels Pa, which has a circular shape similar to the circular shape of the light-emitting area as illustrated in  FIG.  8 B , may reduce diffraction and scattering of light by an edge, a corner, and the like of the second pixel electrode  121 ′. 
     The auxiliary pixel circuits PCa that implement the light-emitting of the auxiliary sub-pixels Pa may be arranged in the peripheral area NDA. As the auxiliary pixel circuits PCa are not arranged in the first area DA 1 , the transmissive area TA greater than the first area DA 1  may be secured. Furthermore, as wirings that apply a constant voltage and signals to the auxiliary pixel circuit PCa are not arranged in the first area DA 1 , the auxiliary sub-pixels Pa may be freely arranged without considering the arrangement of the wirings. 
     The auxiliary pixel circuits PCa may be connected to the auxiliary sub-pixels Pa by connection wirings. The connection wirings may include at least one of a transparent connection wiring TWL or a metal connection wiring TWL’. 
     The transparent connection wiring TWL may be arranged at least partially in the first area DA 1 , and may include a transparent conductive material. For example, the transparent connection wiring TWL may include a transparent conducting oxide (TCO). The transparent connection wiring TWL may include a conductive oxide such as an indium tin oxide (ITO), an indium zinc oxide (IZO), a zinc oxide (ZnO), an indium oxide (ln 2 O 3 ), an indium gallium oxide (IGO), or an aluminum zinc oxide (AZO). 
     The connection of the transparent connection wiring TWL to the auxiliary sub-pixels Pa may mean that the transparent connection wiring TWL is electrically connected to a pixel electrode of an auxiliary display element that implements the auxiliary sub-pixels Pa. 
     The transparent connection wiring TWL may be connected to the auxiliary pixel circuits PCa through the metal connection wiring TWL’. The metal connection wiring TWL’ may be a wiring that is arranged in the peripheral area NDA and connected to the auxiliary pixel circuit PCa. 
     The metal connection wiring TWL’ may include a conductive material including molybdenum (Mo), aluminum (Al), copper (Cu), titanium (Ti), and the like, and may be formed as a multilayer or a single layer including the above material. The metal connection wiring TWL’ may include a plurality of metal connection wirings between the auxiliary pixel circuits PCa. 
     In some embodiments, the metal connection wiring TWL’ may include a first metal connection wiring TWL1′ and a second metal connection wiring TWL2′, which are arranged in different layers. For example, the first metal connection wiring TWL1′ may be arranged in the same layer as a data line DL, and may include the same material as the data line DL. The second metal connection wiring TWL2′ may be arranged with the first metal connection wiring TWL1′ and an insulating layer therebetween. For example, the second metal connection wiring TWL2′ is arranged in the same layer as a first pixel electrode  121  (see  FIG.  9 A ) of the organic light-emitting diode OLED, and may include the same material as the first pixel electrode  121 . Alternatively, the second metal connection wiring TWL2′ may be arranged in the same layer as a connection electrode CM (see  FIG.  9 A ), and may include the same material as the connection electrode CM. 
     The first metal connection wiring TWL1′ and the second metal connection wiring TWL2′ may be arranged between the auxiliary pixel circuits PCa, and may be provided as being at least partially bent on a plane. In some embodiments, the first metal connection wiring TWL1′ and the second metal connection wiring TWL2′, which are arranged in different layers, may each include a plurality of metal connection wirings, and the first metal connection wiring TWL1′ and the second metal connection wiring TWL2′ may be alternately arranged in an area between the auxiliary pixel circuits PCa. 
     The transparent connection wiring TWL may be arranged in the first area DA 1 , and may be connected to the metal connection wiring TWL’ at an edge of the first area DA 1 . The transparent connection wiring TWL may include a transparent conductive material. 
     The metal connection wiring TWL’ and the transparent connection wiring TWL may be arranged in the same layer or in different layers. When the metal connection wiring TWL’ and the transparent connection wiring TWL are arranged in different layers, the metal connection wiring TWL’ and the transparent connection wiring TWL may be connected to each other through a contact hole. 
     The metal connection wiring TWL’ may have higher conductivity than that of the transparent connection wiring TWL. As the metal connection wiring TWL’ is arranged in the peripheral area NDA, there is no need to secure light transmittance, and thus, a material having lower light transmittance but higher conductivity than the transparent connection wiring TWL may be employed. Accordingly, a resistance value of the transparent connection wiring TWL may be reduced. 
     The scan line SL may include a main scan line SLm connected to the main pixel circuits PCm and an auxiliary scan line SLa connected to the auxiliary pixel circuits PCa. The main scan line SLm may extend in the x direction, and may be connected to the main pixel circuits PCm that is arranged in the same row. The main scan line SLm may not be arranged in the first area DA 1 . In other words, the main scan line SLm may be short-circuited with respect to the first area DA 1 . In this case, the main scan line SLm arranged to the left of the first area DA 1  may receive a signal from a first scan driving circuit SDR1 (see  FIGS.  5  or  7   ), while the main scan line SLm arranged to the right of the first area DA 1  may receive a signal from a second scan driving circuit SDR2 (see  FIGS.  5  or  7   ). 
     The auxiliary scan line SLa may be connected to the auxiliary pixel circuits PCa for driving the auxiliary sub-pixels Pa arranged in the same row among the auxiliary pixel circuits PCa arranged in the same row. 
     The main scan line SLm and the auxiliary scan line SLa may be connected by a scan connection line SWL, and the same signal may be applied to the main sub-pixels Pm arranged in the same row and to the auxiliary pixel circuits PCa for driving the auxiliary sub-pixels Pa. 
     The scan connection line SWL is arranged in a different layer from the main scan line SLm and the auxiliary scan line SLa, and the scan connection line SWL may be connected to each of the main scan line SLm and the auxiliary scan line Sla through contact holes. The scan connection line SWL may be arranged in the peripheral area NDA. 
     The data line DL may include the main data line DLm connected to the main pixel circuits PCm, and an auxiliary data line DLa connected to the auxiliary pixel circuits PCa. The main data line DLm may extend in the y direction, and may be connected to the main pixel circuits PCm arranged in the same row. The auxiliary data line DLa may extend in the y direction, and may be connected to the auxiliary pixel circuits PCa arranged in the same row. 
     The main data line DLm and the auxiliary data line DLa may be arranged apart from each other with the first area DA 1  therebetween. The main data line DLm and the auxiliary data line DLa may be connected by a data connection line DWL, and the same signal may be applied to the main sub-pixels Pm arranged in the same column, along with the auxiliary pixel circuits PCa for driving the auxiliary sub-pixels Pa. 
     The data connection line DWL may be arranged to bypass the first area DA 1 . The data connection line DWL may be arranged overlapping the main pixel circuits PCm arranged in the second area DA 2 . As the data connection line DWL is arranged in the second area DA 2 , there is no need to secure a separate space where the data connection line DWL is arranged, and thus, a dead space area may be reduced. 
     As the data connection line DWL is arranged in a different layer from the main data line DLm and the auxiliary data line DLa, the data connection line DWL may be connected to each of the main data line DLm and the auxiliary data line DLa through contact holes. 
       FIG.  9 A  is a schematic cross-sectional view showing parts of the display panel  10 , that is, parts of the first area DA 1 , the second area DA 2 , and the peripheral area NDA, according to one or more embodiments. 
     Referring to  FIG.  9 A , the auxiliary sub-pixels Pa are arranged in the first area DA 1 , and the main sub-pixels Pm are arranged in the second area DA 2 . 
     A second organic light-emitting diode OLED’ may be arranged in the first area DA 1  as an auxiliary display element. A second pixel circuit PCa including an auxiliary thin film transistor TFTa and an auxiliary storage capacitor Csta may be arranged in the peripheral area NDA. The transparent connection wiring TWL for connecting the second pixel circuit PCa to the second organic light-emitting diode OLED’ may be arranged in the second area DA 2  and the peripheral area NDA. 
     The main pixel circuit PCm including the main thin film transistor TFTm and a main storage capacitor Cstm, and a first organic light-emitting diode OLED, as a main display element, and which is connected to the main pixel circuit PCm, may be arranged in the second area DA 2 . 
     In one or more embodiments, an example in which an organic light-emitting diode OLED is employed as a display element is described. In one or more other embodiments, an inorganic emission element or a quantum-dot emission element may be employed as a display element. 
     A structure in which elements included in the display panel  10  are stacked is described below. The display panel  10  may be provided by stacking the substrate  100 , a buffer layer  111 , the circuit layer PCL, and the display element layer EDL. 
     The buffer layer  111  may be located on the substrate  100 , may reduce or prevent infiltration of foreign materials such as moisture or external air from under the substrate  100 , and may provide a planarized surface to an upper portion of the substrate  100 . The buffer layer  111  may include an inorganic material, such as an oxide or a nitride, an organic material, or an organic/inorganic complex, and may have a single layer or multilayer structure of an inorganic material and an organic material. In one or more embodiments, a barrier layer for reducing or blocking infiltration of external air may be further provided between the substrate  100  and the buffer layer  111 . In some embodiments, the buffer layer  111  may include a silicon oxide (SiO 2 ) or a silicon nitride (SiNx). 
     The circuit layer PCL is arranged above the buffer layer  111 , and may include the pixel circuits PCm and PCa, a first gate insulating layer  112 , a second gate insulating layer  113 , an interlayer insulating layer  115 , a first organic insulating layer  116 , and a second organic insulating layer  117 . The main pixel circuit PCm may include the main thin film transistor TFTm and the main storage capacitor Cstm, and the auxiliary pixel circuit PCa may include the auxiliary thin film transistor TFTa and the auxiliary storage capacitor Csta. 
     The main thin film transistor TFTm and the auxiliary thin film transistor TFTa may be arranged above the buffer layer  111 . The main thin film transistor TFTm may include a first semiconductor layer A 1 , a first gate electrode G 1 , a first source electrode S 1 , and a first drain electrode D 1 . The main thin film transistor TFTm may be connected to the first organic light-emitting diode OLED to drive the first organic light-emitting diode OLED. The auxiliary thin film transistor TFTa may be connected to the second organic light-emitting diode OLED’ to drive the second organic light-emitting diode OLED’. As the auxiliary thin film transistor TFTa has a similar structure to the main thin film transistor TFTm, the description of the auxiliary thin film transistor TFTa is replaced with the description of the main thin film transistor TFTm. 
     The first semiconductor layer A 1  is arranged above the buffer layer  111  and may include polysilicon. In one or more other embodiments, the first semiconductor layer A 1  may include amorphous silicon. In one or more other embodiments, the first semiconductor layer A 1  may include an oxide of at least one material selected from the group consisting of indium (In), gallium (Ga), stannum (Sn), zirconium (Zr), vanadium (V), hafnium (Hf), cadmium (Cd), germanium (Ge), chromium (Cr), Ti, and zinc (Zn). The first semiconductor layer A 1  may include a channel region, and may include a source region and a drain region that are doped with impurities. 
     The first gate insulating layer  112  may be provided to cover the first semiconductor layer A 1 . The first gate insulating layer  112  may include an inorganic insulating material such as SiO 2 , SiNx, a silicon oxynitride (SiOxNy), an aluminum oxide (Al 2 O 3 ), a titanium oxide (TiO 2 ), a tantalum oxide (Ta 2 O 5 ), a hafnium oxide (HfO 2 ), or a zinc oxide (ZnO 2 ). The first gate insulating layer  112  may be a single layer or multilayer including the above-described inorganic insulating material. 
     The first gate electrode G 1  is arranged above the first gate insulating layer  112  to overlap the first semiconductor layer A 1 . The first gate electrode G 1  may include Mo, Al, Cu, Ti, and the like, and may be provided as a single layer or multilayer. As an example, the first gate electrode G 1  may be a single layer of Mo. 
     The second gate insulating layer  113  may be provided to cover the first gate electrode G 1 . The second gate insulating layer  113  may include an inorganic insulating material such as SiO 2 , SiNx, SiOxNy, Al 2 O 3 , TiO 2 , Ta 2 O 5 , HfO 2 , ZnO 2 , or the like. The second gate insulating layer  113  may be a single layer or multilayer including the above-described inorganic insulating material. 
     An upper electrode CE2m of the main storage capacitor Cstm and an upper electrode CE2a of the auxiliary storage capacitor Csta may be arranged above the second gate insulating layer  113 . 
     The upper electrode CE2m of the main storage capacitor Cstm may overlap the first gate electrode G 1  thereunder in the second area DA 2 . The first gate electrode G 1  and the upper electrode CE2m, which overlap each other with the second gate insulating layer  113  therebetween, may constitute the main storage capacitor Cstm. The first gate electrode G 1  may also function as a lower electrode CE 1  m of the main storage capacitor Cstm. 
     The upper electrode CE2a of the auxiliary storage capacitor Csta may overlap a gate electrode of the auxiliary thin film transistor TFTa thereunder in the peripheral area NDA. The gate electrode of the auxiliary thin film transistor TFTa may also function as a lower electrode CE1a of the auxiliary storage capacitor Csta. 
     The upper electrodes CE2m and CE2a may include Al, platinum (Pt), palladium (Pd), silver (Ag), magnesium (Mg), gold (Au), nickel (Ni), neodymium (Nd), iridium (Ir), chromium (Cr), calcium (Ca), Mo, Ti, tungsten (W), and/or Cu, and may be a single layer or multilayer of the above-described material. 
     The interlayer insulating layer  115  may cover the upper electrodes CE2m and CE2a. The interlayer insulating layer  115  may include SiO 2 , SiNx, SiOxNy, Al 2 O 3 , TiO 2 , Ta 2 O 5 , HfO 2 , ZnO 2 , or the like. The interlayer insulating layer  115  may be a single layer or multilayer including the above-described inorganic insulating material. 
     A source electrode S 1  and a drain electrode D 1  may be arranged above the interlayer insulating layer  115 . The source electrode S 1  and the drain electrode D 1  may include a conductive material including Mo, Al, Cu, Ti, and the like, and may be provided as a multilayer or a single layer including the above-described material. As an example, the source electrode S 1  and the drain electrode D 1  may have a multilayer structure of Ti/Al/Ti. 
     An inorganic insulating layer IL of the display panel  10  may include an opening H 1  corresponding to the first area DA 1 . For example, when the first gate insulating layer  112 , the second gate insulating layer  113 , and the interlayer insulating layer  115  are collectively referred to as the inorganic insulating layer IL, the inorganic insulating layer IL may have the opening H 1  corresponding to the first area DA 1 . The opening H 1  may expose part of an upper surface of the substrate  100  or the buffer layer  111 . The opening H 1  may include a first opening  112   a  of the first gate insulating layer  112 , a second opening  113   a  of the second gate insulating layer  113 , and a third opening  115   a  of the interlayer insulating layer  115 , which are overlapped with one another and formed to correspond to the first area DA 1 . The openings  112   a ,  113   a , and  115   a  may each be formed in a separate process, or may be concurrently or substantially simultaneously formed in the same process. The opening H 1  of the inorganic insulating layer IL may be filled with the first organic insulating layer  116 . 
     The first organic insulating layer  116  may cover the source electrodes S 1  and S 2  and the drain electrodes D 1  and D 2  of the second area DA 2  and the peripheral area NDA, and may fill the opening H 1  of the inorganic insulating layer IL in the first area DA 1 . 
     The first organic insulating layer  116  may include general purpose polymers such as photosensitive polyimide, polyimide, polystyrene (PS), polycarbonate (PC), BCB, hexamethyldisiloxane (HMDSO), polymethylmethacrylate (PMMA), or PS, polymer derivatives having a phenolic group, acrylic polymer, imide-based polymer, arylether-based polymer, amide-based polymer, fluorine-based polymer, p-xylene-based polymer, vinyl alcohol-based polymer, or the like. 
     Alternatively, the first organic insulating layer  116  may include a siloxane organic material. The siloxane organic material may include hexamethyldisiloxane, octamethyltrisiloxane, decamethyltetrasiloxane, dodecamethylpentasiloxane, and polydimethylsiloxane. 
     A refractive index of the first organic insulating layer  116  may be about 1.4 to about 1.6 with respect to a 550 nm wavelength. A connection electrode CM and various wirings, for example, the data line DL, may be arranged above the first organic insulating layer  116 , which is advantageous to high integration. 
     The transparent connection wiring TWL may be provided above the first organic insulating layer  116  in the first area DA 1 . The transparent connection wiring TWL extends from the peripheral area NDA to the second area DA 2 , and may connect between the second organic light-emitting diode OLED’ and the auxiliary pixel circuit PCa. 
     The transparent connection wiring TWL may be connected to the metal connection wiring TWL’. The metal connection wiring TWL’ is arranged in the peripheral area NDA to be connected to the auxiliary pixel circuit PCa, for example, the auxiliary thin film transistor TFTa. The transparent connection wiring TWL may be arranged in the transmissive area TA of the first area DA 1 . An end portion of the transparent connection wiring TWL may cover an end portion of the metal connection wiring TWL’. 
     The metal connection wiring TWL’ may include a conductive material including Mo, Al, Cu, Ti, and the like, and may be a multilayer or a single layer including the above-described material. In some embodiments, the metal connection wiring TWL’ may be arranged on the same layer as the connection electrode CM, and may include the same material as the connection electrode CM. In some embodiments, the metal connection wiring TWL’ may be arranged on the same layer as the data line DL, and may include the same material as the data line DL. However, the disclosure is not limited thereto. The metal connection wiring TWL’ may be arranged in various layers. For example, the metal connection wiring TWL’ may be arranged in the same layer as the first pixel electrode  121 . 
     The transparent connection wiring TWL may include a transparent conductive material. For example, the transparent connection wiring TWL may include a transparent conducting oxide (TCO). The transparent connection wiring TWL may include a conductive oxide such as ITO, IZO, ZnO, ln 2 O 3 , IGO, or AZO. 
     The metal connection wiring TWL’ may have higher conductivity than the transparent connection wiring TWL. As the metal connection wiring TWL’ is arranged in the peripheral area NDA, there is no need to secure light transmittance, and thus, a material having lower light transmittance than, but also having higher conductivity than, the transparent connection wiring TWL may be employed. 
     The second organic insulating layer  117  may be arranged above the first organic insulating layer  116  to cover the transparent connection wiring TWL. The second organic insulating layer  117  may have a flat upper surface such that the first pixel electrode  121  and the second pixel electrode  121 ′ arranged above the second organic insulating layer  117  are formed flat. The second organic insulating layer  117  may include a siloxane organic material having high light transmittance and high flatness. The siloxane organic material may include hexamethyldisiloxane, octamethyltrisiloxane, decamethyltetrasiloxane, dodecamethylpentasiloxane, and polydimethylsiloxane. 
     Alternatively, the second organic insulating layer  117  may include general purpose polymers such as photosensitive polyimide, polyimide, BCB, HMDSO, PMMA, or PS, polymer derivatives having a phenolic group, acrylic polymer, imide-based polymer, arylether-based polymer, amide-based polymer, fluorine-based polymer, p-xylene-based polymer, vinyl alcohol-based polymer, or the like. 
     The organic light-emitting diodes OLED and OLED’ may be arranged above the second organic insulating layer  117 . The pixel electrodes  121  and  121 ′ of the organic light-emitting diodes OLED and OLED’ may be respectively connected to the pixel circuits PCm and PCa through the connection electrode CM and the transparent connection wiring TWL arranged above the first organic insulating layer  116 . 
     The first pixel electrode  121  and the second pixel electrode  121 ′ may include a conductive oxide such as ITO, IZO, ZnO, ln 2 O 3 , IGO, or AZO. The first pixel electrode  121  and the second pixel electrode  121 ′ may include a reflective film including Ag, Mg, Al, Pt, Pd, Au, Ni, Nd, Ir, Cr, or a compound thereof. For example, the first pixel electrode  121  and the second pixel electrode  121 ′ may each have a structure having films including ITO, IZO, ZnO, or ln 2 O 3  above/below the above-described reflective film. In this case, the first pixel electrode  121  and the second pixel electrode  121 ′ may have a stack structure of ITO/Ag/ITO. 
     A pixel defining layer  119  may include, or define, a first opening OP 1  and a second opening OP 2  that are arranged above the second organic insulating layer  117 , may cover edges of each of the first pixel electrode  121  and the second pixel electrode  121 ′, and may expose center portions of the first pixel electrode  121  and the second pixel electrode  121 ′. The first opening OP 1  and the second opening OP 2  define the size and the shape of a light-emitting area, that is, the sub-pixels Pm and Pa, of the organic light-emitting diodes OLED and OLED’. 
     The pixel defining layer  119  may reduce or prevent the likelihood of generation of an arc at the edges of the pixel electrodes  121  and  121 ′ by increasing a distance between the edges of the pixel electrodes  121  and  121 ′ and a counter electrode  123  that is above the pixel electrodes  121  and  121 ′. The pixel defining layer  119  may include an organic insulating material, such as polyimide, polyamide, acryl resin, benzocyclobutene, HMDSO, phenol resin, and the like, by a method such as spin coating and the like. 
     A spacer SPC may be arranged above the pixel defining layer  119 . The spacer SPC may reduce or prevent the occurrence of scratches during a mask process. The spacer SPC may include an organic insulating material such as polyimide, polyamide, acryl resin, benzocyclobutene, HMDSO, phenol resin, and the like. In some embodiments, the spacer SPC may be concurrently or substantially simultaneously formed with the pixel defining layer  119  using the same material as the pixel defining layer  119  by using a half-tone mask. 
     A first emission layer  122   b  and a second emission layer  122   b ′ are respectively arranged in the first opening OP 1  and the second opening OP 2  of the pixel defining layer  119  to respectively correspond to the first pixel electrode  121  and the second pixel electrode  121 ′. The first emission layer  122   b  and the second emission layer  122   b ′ may include a polymer material or a low molecular weight material, and emit red, green, blue, or white light. 
     An organic functional layer  122   e  may be arranged above and/or below each of the first emission layer  122   b  and the second emission layer  122   b ′ (e.g., may have respective portions above and below the first emission layer  122   b  and the second emission layer  122   b ′). The organic functional layer  122   e  may include a first functional layer  122   a  and/or a second functional layer  122   c . The first functional layer  122   a  and/or the second functional layer  122   c  may be omitted in one or more other embodiments. 
     The first functional layer  122   a  may be arranged below the first emission layer  122   b  and the second emission layer  122   b ′. The first functional layer  122   a  may be a single layer or multilayer including an organic material. The first functional layer  122   a  may be a hole transport layer (HTL) having a single layer structure. Alternatively, the first functional layer  122   a  may include a hole injection layer (HIL) and a hole transport layer (HTL). The first functional layer  122   a  may be integrally formed to correspond to the organic light-emitting diodes OLED and OLED’. 
     The second functional layer  122   c  may be arranged above the first emission layer  122   b  and the second emission layer  122   b ′. The second functional layer  122   c  may be a single layer or multilayer including an organic material. The second functional layer  122   c  may include an electron transport layer (ETL) and/or an electron injection layer (EIL). The second functional layer  122   c  may be formed to correspond to the organic light-emitting diodes OLED and OLED’ respectively included in the second area DA 2  and the first area DA 1 . 
     The counter electrode  123  is arranged above the second functional layer  122   c . The counter electrode  123  may include a conductive material having a low work function. For example, the counter electrode  123  may include a transparent or semitransparent layer including Ag, Mg, Al, Pt, Pd, Au, Ni, Nd, Ir, Cr, lithium (Li), Ca, or an alloy thereof, and the like. Alternatively, the counter electrode  123  may further include a layer such as ITO, IZO, ZnO, or ln 2 O 3  above the transparent/semi-transparent layer including the above-described material. The counter electrode  123  may be integrally formed to correspond to the organic light-emitting diodes OLED and OLED’. 
     In the second area DA 2 , the layers from the first pixel electrode  121  to the counter electrode  123  may constitute the first organic light-emitting diode OLED. In the first area DA 1 , the layers from the second pixel electrode  121 ′ to the counter electrode  123  may constitute the organic light-emitting diode OLED’. 
     An upper layer  150  including an organic material may be formed above the counter electrode  123 . The upper layer  150  may be provided to protect the counter electrode  123  while also increasing light extraction efficiency. The upper layer  150  may include an organic material having a higher refractive index than the counter electrode  123 . Alternatively, the upper layer  150  may be provided by stacking layers having different refractive indexes. For example, the upper layer  150  may be provided by stacking a high refractive index layer / a low refractive index layer / a high refractive index layer. In this state, the refractive index of the high refractive index layer may be about 1.7 or more, and the refractive index of the low refractive index layer may be about 1.3 or less. 
     The upper layer  150  may additionally include LiF. Alternatively, the upper layer  150  may additionally include an inorganic insulating material such as SiO 2  or SiNx. 
     The thin film encapsulation layer TFE is arranged above the upper layer  150 , and the organic light-emitting diodes OLED and OLED’ may be sealed by the thin film encapsulation layer TFE. The thin film encapsulation layer TFE may reduce or prevent infiltration of external moisture or foreign materials into the organic light-emitting diodes OLED and OLED’. 
     The thin film encapsulation layer TFE may include at least one inorganic encapsulation layer and at least one organic encapsulation layer. In this regard,  FIG.  9 A  illustrates that the thin film encapsulation layer TFE has a stack structure of the first inorganic encapsulation layer  131 , the organic encapsulation layer  132 , and the second inorganic encapsulation layer  133 . In one or more other embodiments, the number of organic encapsulation layers, the number of inorganic encapsulation layers, and a stack order may be changed. 
     The first inorganic encapsulation layer  131  and the second inorganic encapsulation layer  133  may include one or more inorganic insulating materials such as SiO 2 , SiNx, SiOxNy, Al 2 O 3 , TiO 2 , Ta 2 O 5 , HfO 2 , or ZnO 2 , and may be formed by a chemical deposition method (CVD) and the like. The organic encapsulation layer  132  may include a polymer-based material. The polymer-based material may include silicon-based resin, acrylic resin, for example, polymethylmethacrylate, polyacryl acid, and the like, epoxy-based resin, polyimide, polyethylene, and the like. The first inorganic encapsulation layer  131 , the organic encapsulation layer  132 , and the second inorganic encapsulation layer  133  may be integrally formed to cover the first area DA 1  and the second area DA 2 . 
       FIG.  9 A  illustrates that the inorganic insulating layer IL includes the opening H 1  corresponding to the first area DA 1 , but the disclosure is not limited thereto. As illustrated in  FIG.  9 B , the inorganic insulating layer IL may not include an opening corresponding to the first area DA 1 , and may be continuously arranged in the first area DA 1 . Even when the inorganic insulating layer IL does not include an opening, the light transmittance of the first area DA 1  may be secured through a relationship of the refractive indexes and the like of the inorganic insulating layer IL and an organic insulating layer OL. 
       FIGS.  10  and  11    are schematic plan views showing part of a display area according to one or more embodiments. 
     Referring to  FIG.  10    first, the display apparatus according to one or more embodiments may include the first area DA 1  where the auxiliary sub-pixels Pa are arranged and the second area DA 2  where the main sub-pixels Pm are arranged. The second area DA 2  may be arranged to surround the first area DA 1 . In one or more embodiments, the auxiliary sub-pixels Pa arranged in the first area DA 1  may be arranged to have a corresponding arrangement according to the first row to the n-th row (1R, 2R, ..., n-1R, and nR) and the first column to the m-th column (1C, 2C, ..., m-1C, and mC). 
     The first area DA 1 , as a kind of a component area, is where the auxiliary sub-pixels Pa are arranged, and an area where the auxiliary sub-pixels Pa are not arranged may function as the transmissive area TA. As illustrated in  FIG.  10   , the first interval d1 between the auxiliary sub-pixels Pa and the main sub-pixels Pm that are arranged closest to the first boundary portion BP 1  may be different from the second interval d2 between the auxiliary sub-pixels Pa and others of the main sub-pixels Pm that are arranged closest to the second boundary portion BP 2 .  FIG.  10    illustrates that the first interval d1 is greater than the second interval d2. 
     In other words, when all of the auxiliary sub-pixels Pa arranged in the first area DA 1  are regarded as one auxiliary sub-pixel unit PaU, the auxiliary sub-pixel unit PaU may be arranged by being shifted by a first distance S 1  in one direction, for example, in the -y direction, compared with a comparative example, in which the pixel unit PaU’ is arranged at the center of the first area DA 1 . In other words, the auxiliary sub-pixel unit PaU may be arranged by being shifted by a certain distance (the first distance S 1 ) in a direction from the first row 1R toward the n-th row nR, or in a direction opposite thereto. In this state, the pixel unit PaU’ of the comparative example being arranged generally at the “center” of the first area DA 1  may mean that the pixel unit PaU’ is arranged apart from each of the first to fourth boundary portions BP 1 , BP 2 , BP 3 , and BP 4 , by the same distance. As the auxiliary sub-pixel unit PaU is arranged by being shifted in one direction, for example, in the -y direction, by the first distance S 1 , the abovementioned first interval d1 corresponding to the first boundary portion BP 1  may be greater than the abovementioned second interval d2 corresponding to the second boundary portion BP 2 . 
     The above-described structure may be provided to remove luminance imbalance at the edge of the first area DA 1  because a luminance in a corresponding boundary portion, for example, the first boundary portion BP 1 , in the first area DA 1  is greater than a luminance in a boundary portion opposite thereto, for example, the second boundary portion BP 2 . The luminance imbalance may occur because the arrangements of the auxiliary sub-pixels Pa arranged at the edge of the first area DA 1  are not identical with respect to the first to fourth boundary portions BP 1 , BP 2 , BP 3 , and BP 4 . For example, when first auxiliary sub-pixels having a relatively high luminance, for example, green sub-pixels, are arranged in the first boundary portion BP 1 , second auxiliary sub-pixels having a relatively low luminance, for example, red sub-pixels and/or blue sub-pixels, are arranged in the second boundary portion BP 2 , a luminance in the vicinity of the first boundary portion BP 1  may be greater than a luminance in the vicinity of the second boundary portion BP 2 . 
     In other words, as in one or more embodiments, when the luminance of the first boundary portion BP 1  is greater than the luminance of the second boundary portion BP 2 , by shifting the whole of the auxiliary sub-pixel unit PaU in a direction, for example, in the -y direction toward the second boundary portion BP 2 , the first interval d1 between the auxiliary sub-pixels Pa and the main sub-pixels Pm in the first boundary portion BP 1  is implemented to be greater than the second interval d2 between the auxiliary sub-pixels Pa and the main sub-pixels Pm in the second boundary portion BP 2 , and thus, the luminance of the first boundary portion BP 1  is decreased while the luminance of the second boundary portion BP 2  is relatively increased, thereby mitigating or reducing the luminance imbalance of the auxiliary sub-pixels Pa arranged in the first area DA 1 . 
     Referring to  FIG.  11   , the auxiliary sub-pixel unit PaU may be arranged by being shifted in one direction, for example, in the -y direction, by the first distance S 1 , and also shifted in another direction, for example, in the -x direction, by a second distance S 2 , compared with the comparative example in which the pixel unit PaU’ is generally arranged at the center of the first area DA 1 . As the auxiliary sub-pixel unit PaU is arranged by being shifted in one direction, for example, in the -y direction, and in another direction, for example, in the -x direction, respectively by the first and second distances S 1  and S 2 , the first and fourth intervals d1 and d4 between the auxiliary sub-pixels Pa and the main sub-pixels Pm arranged closest to the first and fourth boundary portions BP 1  and BP 4  may be greater than the second and third intervals d2 and d3 between the auxiliary sub-pixels Pa and the main sub-pixels Pm arranged closest to the second and third boundary portions BP 2  and BP 3 . 
     The above-described structure may be provided to remove luminance imbalance at the edge of the first area DA 1  because a luminance in a corresponding boundary portion, for example, the first and fourth boundary portions BP 1  and BP 4 , in the first area DA 1  is greater than a luminance in a boundary portion opposite thereto, for example, the second and third boundary portions BP 2  and BP 3 . For example, when green sub-pixels having a relatively high luminance are arranged in the first and fourth boundary portions BP 1  and BP 4 , and red sub-pixels and/or blue sub-pixels having a relatively low luminance are arranged in the second and third boundary portions BP 2  and BP 3 , a luminance in the vicinity of the first and fourth boundary portions BP 1  and BP 4  may be greater than a luminance in the vicinity of the second and third boundary portions BP 2  and BP 3 . The first to fourth boundary portions BP 1 , BP 2 , BP 3 , and BP 4  and the arrangement of the main sub-pixels and the auxiliary sub-pixels arranged adjacent thereto are described below in detail with reference to  FIGS.  12  to  15   . 
     In the embodiments corresponding to  FIG.  11   , the first distance S 1  and the second distance S 2  may be the same as each other, or different from each other. The first distance S 1  and the second distance S 2  may be respectively adjusted according to a luminance difference between the first boundary portion BP 1  and the second boundary portion BP 2  and a luminance difference between the third boundary portion BP 3  and the fourth boundary portion BP 4 . 
     In the display apparatus according to one or more embodiments, as illustrated in  FIGS.  10  and  11    described above, the whole of the auxiliary sub-pixels Pa arranged in the first area DA 1  is regarded as one auxiliary sub-pixel unit PaU, and thus, the auxiliary sub-pixel unit PaU may be entirely shifted, or as illustrated in  FIG.  13    to be described below, only pixels that emit light of a corresponding color included in the auxiliary sub-pixel unit PaU may be shifted. 
       FIGS.  12  to  15    are schematic plan views showing various pixel arrangements in a display area of a display apparatus, according to embodiments. 
     Referring to  FIG.  12   , the auxiliary sub-pixels Pa arranged in the first area DA 1  may be entirely shifted in the -y direction. In other words, the auxiliary sub-pixels Pa may be shifted from the first boundary portion BP 1  to the second boundary portion BP 2  symmetrical thereto. 
     In  FIG.  12   , as in  FIG.  10    described above, as the auxiliary sub-pixels Pa are entirely shifted in the -y direction, both of first and second widths (e.g., first and second distances) w1 and w2 between respective ones of the auxiliary sub-pixels Pa in a y-axis direction may be the same. In detail, the auxiliary sub-pixels Pa may include first auxiliary pixels, for example, the second sub-pixel Pag, arranged in a virtual first line, and second auxiliary pixels, for example, the first sub-pixel Par and the third sub-pixel Pab, and third auxiliary pixels, for example, the first sub-pixel Par and the third sub-pixel Pab, the second and third auxiliary pixels being respectively arranged in virtual second and third lines L 2  and L 3  that are parallel to the virtual first line L 1 . As an example, the second auxiliary pixels, for example, the first sub-pixel Par and the third sub-pixel Pab, and third auxiliary pixels, for example, the first sub-pixel Par and the third sub-pixel Pab, may have the same pixel arrangement. In the embodiments corresponding to  FIG.  12   , the first to third lines L 1 , L 2 , and L 3  are all illustrated as being parallel to an x-axis direction. 
     With respect to the first line L 1 , the first width w1 between the first auxiliary pixels, for example, the second sub-pixel Pag, and the second auxiliary pixels, for example, the first sub-pixel Par and the third sub-pixel Pab, which are closest to one side of the first auxiliary pixels, may be the same as the second width w2 between the first auxiliary pixels and the third auxiliary pixels, for example, the first sub-pixel Par and the third sub-pixel Pab, which are closest to the other side of the first auxiliary pixels. 
     As the auxiliary sub-pixels Pa are entirely shifted in the -y direction, the first interval d1 between the auxiliary sub-pixels Pa and the main sub-pixels Pm, which are arranged closest to the first boundary portion BP 1 , may be greater than the second interval d2 between the auxiliary sub-pixels Pa and the main sub-pixels Pm, which are arranged closest to the second boundary portion BP 2 . 
     In one or more embodiments, the auxiliary sub-pixels Pa arranged in the first area DA 1  may be entirely shifted in the -y direction and the -x direction, as described above in  FIG.  11   . 
     The arrangement of the main sub-pixels Pm in the second area DA 2  adjacent to first boundary portion BP 1  may be the same as the arrangement of the auxiliary sub-pixels Pa in the first area DA 1  adjacent in the second boundary portion BP 2  that is symmetrical to the first boundary portion BP 1 . As illustrated in  FIG.  12   , the first sub-pixels Pmr that are red sub-pixels and the third sub-pixels Pmb that are blue sub-pixels are alternately arranged in the second area DA 2  adjacent to the first boundary portion BP 1 , and the first sub-pixels Par and the third sub-pixels Pab may be alternately arranged in the first area DA 1  adjacent to the second boundary portion BP 2 . 
     Furthermore, the arrangement of the main sub-pixels Pm in the second area DA 2  adjacent to the third boundary portion BP 3  may be the same as the arrangement of the auxiliary sub-pixels Pa in the first area DA 1  adjacent to the fourth boundary portion BP 4  that is symmetrical to the third boundary portion BP 3 . As illustrated in  FIG.  12   , the second sub-pixels Pmg that are green sub-pixels are arranged in the second area DA 2  adjacent to the third boundary portion BP 3 , and the second sub-pixels Pag that are green sub-pixels may be arranged in the first area DA 1  adjacent to the fourth boundary portion BP 4 . 
     Referring to  FIG.  13   , while the arrangement of the auxiliary sub-pixels Pa of  FIG.  13    is similar to the arrangement of the auxiliary sub-pixels Pa of  FIG.  12    described above, there is a difference from the embodiments corresponding to  FIG.  12    in that it is not that the auxiliary sub-pixels Pa are entirely shifted, but that only the sub-pixels that emit light of a corresponding color are shifted. 
     In one or more embodiments,  FIG.  13    illustrates that only the second sub-pixels Pag that emit green light are shifted. As a comparative example, before being shifted, a second sub-pixel Pag′ may be arranged on a first line L′, and the second sub-pixel Pag′ may be moved by a certain distance S 1  in one direction, for example, in the -y direction, and arranged on the first line L 1  as illustrated in  FIG.  13   . 
     In this case, as only the first auxiliary pixels, for example, the second sub-pixels Pag, among the auxiliary sub-pixels Pa, are shifted in the -y direction, with respect to the first line L 1 , the first width w1 between the first auxiliary pixels, for example, the second sub-pixel Pag, and the second auxiliary pixels, for example, the first sub-pixel Par and the third sub-pixel Pab, which are closest to one side of the first auxiliary pixels, may be greater than the second width w2 between the first auxiliary pixels and the third auxiliary pixels, for example, the first sub-pixel Par and the third sub-pixel Pab, which are closest to the other side of the first auxiliary pixels. 
     In the embodiments corresponding to  FIG.  12   , as the auxiliary sub-pixels Pa are entirely shifted in the -y direction, the interval between the auxiliary sub-pixels Pa and the main sub-pixels Pm in the second boundary portion BP 2  may be excessively decreased, and in this case, design according to design rules may not be easy. 
     Accordingly, as illustrated in  FIG.  13   , as only the first auxiliary pixels, for example, the second sub-pixel Pag, among the auxiliary sub-pixels Pa, are shifted in the -y direction, the second interval d2 between the auxiliary sub-pixels Pa and the main sub-pixels Pm, which are arranged closest to the second boundary portion BP 2 , is maintained, and the first interval d1 between the auxiliary sub-pixels Pa and the main sub-pixels Pm, which are arranged closest to the first boundary portion BP 1 , may be implemented to be greater than the second interval d2. 
     As described above, in  FIGS.  12  or  13   , as the auxiliary sub-pixels Pa are entirely shifted or all corresponding sub-pixels are shifted, in the case of sub-pixels that emit light of the same color in the first area DA 1 , all intervals between the sub-pixels in one direction may be the same. As an example, for the second sub-pixel Pag that emits green light, all intervals dg (see  FIG.  12   ) between the second sub-pixels Pag in the x-axis direction may be identical in the first area DA 1 . Likewise, all intervals dr (see  FIG.  12   ) between the first sub-pixels Par in the x-axis direction may be identical, and all intervals db (see  FIG.  12   ) between the third sub-pixels Pab in the x-axis direction may be identical. Also, respective distances may be identical in the y-axis direction or in a diagonal direction crossing an x-y axis. 
     Referring to  FIG.  14   , the arrangement of the auxiliary sub-pixels Pa of  FIG.  14    is different from the auxiliary sub-pixels Pa of  FIGS.  12  and  13    described above. The auxiliary sub-pixels Pa may include the first sub-pixel Par, the second sub-pixel Pag, and the third sub-pixel Pab. In this state, the second sub-pixel Pag for emitting green light, the first sub-pixel Par for emitting red light, and the third sub-pixel Pab for emitting blue light may have sequentially decreasing luminance. In  FIG.  14   , the second sub-pixel Pag having the highest luminance may be arranged at the same interval in the first area DA 1 . In other words, in the auxiliary sub-pixels Pa closest to the first to fourth boundary portions BP 1 , BP 2 , BP 3 , and BP 4 , the second sub-pixels Pag may be arranged to have the same number and interval. 
     According to one or more embodiments, the second sub-pixel Pag and the third sub-pixel Pab may be alternately arranged in the first row 1R closest to the first boundary portion BP 1 , only the first sub-pixels Par may be arranged in a second row 2R, and only the second sub-pixels Pag may be arranged in a third row 3R. With respect to a comparative example described below, the above-described structure may be such that pixels are shifted in one direction, for example, the +y direction, by the distance S, from a reference line C on which the second sub-pixels Pag are arranged, to a new reference line C′ on which the first sub-pixels Par are arranged. 
     As a comparative example, the first sub-pixels Par′ that are not shifted by the distance S may be arranged in the same row, that is, the same line, as the second sub-pixels Pag that are arranged in the third row 3R. In this case, the luminance in the second boundary portion BP 2  where the first sub-pixel Par′ and the second sub-pixel Pag are alternately arranged may be greater than the luminance in the first boundary portion BP 1  where the second sub-pixel Pag and the third sub-pixel Pab are alternately arranged. Accordingly, in one or more embodiments, to mitigate or reduce such a luminance difference, the first sub-pixel Par having a relatively higher luminance than the third sub-pixel Pab may be shifted in a direction, for example, the +y direction, from the second boundary portion BP 2  to the first boundary portion BP 1 . 
       FIG.  14    illustrates that the first sub-pixels Par are moved only in a direction, for example, the +y direction, from the second boundary portion BP 2  to the first boundary portion BP 1 , but the disclosure is not limited thereto. In one or more other embodiments, when the luminance in the third boundary portion BP 3  is greater than the luminance in the fourth boundary portion BP 4 , the first sub-pixels Par may be moved in a direction, for example, the +x direction, from the third boundary portion BP 3  to the fourth boundary portion BP 4 . 
     Referring to  FIG.  15   , the arrangement of the auxiliary sub-pixels Pa of  FIG.  14    is different from the arrangement of the auxiliary sub-pixels Pa of  FIGS.  12  to  14    described above. In  FIG.  15   , the auxiliary sub-pixels Pa, as one pixel unit PX, may include the first sub-pixel Par, the second sub-pixel Pag, and the third sub-pixel Pab, and the pixel unit PX may be arranged to have a constant interval in the first area DA 1 . 
     According to one or more embodiments, the first sub-pixels Par may be arranged in a first column 1C, which is closest to the third boundary portion BP 3 , the second sub-pixels Pag may be arranged in a second column 2C, and the third sub-pixels Pab may be arranged in a third column 3C. With respect to a comparative example described below, the above-described structure may be such that pixels are shifted in one direction, for example, the +x direction, by a certain distance S, from a reference line C on which the first sub-pixels Par and the second sub-pixels Pag′ are arranged, to a new reference line C′ on which the second sub-pixels Pag are arranged. 
     As a comparative example, the second sub-pixels Pag′ that are not shifted by the distance S may be arranged in the same row, that is, the same line, as the first sub-pixels Par that are arranged in the first column 1C. In this case, the luminance in the third boundary portion BP 3  where the first sub-pixel Par and the second sub-pixel Pag′ are alternately arranged may be greater than the luminance in the fourth boundary portion BP 4  where the third sub-pixel Pab are arranged. Accordingly, in one or more embodiments, to mitigate or reduce such a luminance difference, the second sub-pixel Pag, which has a relatively higher luminance than the third sub-pixel Pab, may be shifted in a direction, for example, the +x direction, from the third boundary portion BP 3  toward the fourth boundary portion BP 4 . 
       FIG.  15    illustrates that only the second sub-pixels Pag are moved in a direction, for example, in the +x direction, from the third boundary portion BP 3  toward the fourth boundary portion BP 4 , but the disclosure is not limited thereto. In one or more other embodiments, like the second sub-pixels Pag, the first sub-pixels Par may also move in a direction, for example, in the +x direction, from the third boundary portion BP 3  toward the fourth boundary portion BP 4 . In this case, for example, a distance covered by the first sub-pixels Par may be less than a distance covered by the second sub-pixels Pag. 
     As described above, the arrangements of the auxiliary sub-pixels Pa described with reference to  FIGS.  10  to  15    are merely examples, and the disclosure is not limited thereto. The auxiliary sub-pixels Pa of the display apparatus according to the present disclosure may have various arrangements in addition to the arrangements of  FIGS.  10  to  15   . 
     Although the above description focuses on a display apparatus, the disclosure is not limited thereto. For example, a method of manufacturing the above display apparatus may belong to the scope of the present disclosure. 
     According to the above-described embodiments of the disclosure, display apparatuses having an extended display area to display an image even in an area where components that are electronic elements are arranged may be implemented. The scope of the present disclosure is not limited by the above effect. 
     It should be understood that embodiments described herein should be considered in a descriptive sense only and not for purposes of limitation. Descriptions of features or aspects within each embodiment should typically be considered as available for other similar features or aspects in other embodiments. While one or more embodiments have been described with reference to the figures, it will be understood by those of ordinary skill in the art that various changes in form and details may be made therein without departing from the spirit and scope as defined by the following claims, with functional equivalents thereof to be included therein.