Patent Publication Number: US-2020285057-A1

Title: Display device

Description:
CROSS-REFERENCE TO RELATED APPLICATION 
     The present application claims priority to and the benefit of Korean Patent Application No. 10-2019-0025424, filed on Mar. 5, 2019, the content of which is hereby incorporated by reference in its entirety. 
     BACKGROUND 
     1. Field 
     Aspects of some example embodiments of the present disclosure relate to a display device providing augmented reality images. 
     2. Description of the Related Art 
     Augmented reality refers to a technology of superimposing a virtual image on a user&#39;s view of a real world image or real world environment and displaying the superimposed images as a single image. The virtual image may be an image in the form of text or graphics, and the real image may be associated with information on real objects observed in the field of view of the device. 
     The augmented reality may be implemented by a head mounted display (HMD) or a head-up display (HUD). When the augmented reality is implemented by the HMD, the HMD may be provided, for example, in the form of a pair of eyeglasses so that a user easily wears it or takes it off as well as carries it. 
     An augmented reality providing device includes a display device to provide the virtual image used to implement the augmented reality. In recent years, there has been a demand to enlarge an area of the display device, which is viewed by the user, that is, a field of view (FOV) of the user. 
     The above information disclosed in this Background section is only for enhancement of understanding of the background and therefore the information discussed in this Background section does not necessarily constitute prior art. 
     SUMMARY 
     Aspects of some example embodiments of the present disclosure include a display device having a relatively reduced thickness and a relatively expanded field of view (FOV). 
     According to some example embodiments of the inventive concept, a display device includes: a lens module including a lens and a reflective module located in the lens and a display module located on at least one side surface of the lens and displaying an image. The lens includes a side surface facing the display module and receiving the image and an exiting surface emitting the image reflected by the reflective module. The side surface includes one or more inclination surfaces. 
     According to some example embodiments of the inventive concept, a display device includes: a lens module including a lens and a reflective module located in the lens and a display module located on at least one side surface of the lens and displaying an image. The lens includes a side surface facing the display module and receiving the image and an exiting surface emitting the image reflected by the reflective module. The side surface includes at least one curved surface. 
     According to some example embodiments, the display device may allow the side surface of the lens, on which the display module is located, to have the one or more inclination surfaces or the curved shape. Thus, the display module having a width greater than a width of the lens may be located on an incident surface. As a result, the FOV of the display device may be widened without increasing the thickness of the display device. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       The above and other aspects of the present disclosure will become more readily apparent by reference to the following detailed description when considered in conjunction with the accompanying drawings wherein: 
         FIG. 1  is a perspective view showing an electronic device including an augmented reality providing device according to some example embodiments of the present disclosure; 
         FIG. 2  is an exploded perspective view showing an augmented reality providing device according to some example embodiments of the present disclosure; 
         FIG. 3  is a cross-sectional view showing an operation of the augmented reality providing device shown in  FIG. 2 ; 
         FIG. 4A  is a view showing a state before coupling of a display module to a lens module of  FIG. 3 ; 
         FIG. 4B  is a view showing a state in which the display module is coupled to a lens module of  FIG. 4A ; 
         FIG. 5A  is a view showing a first inclination surface shown in  FIG. 4A ; 
         FIG. 5B  is a view showing a second inclination surface shown in  FIG. 4A ; 
         FIG. 6A  is a cross-sectional view showing a lens module according to some example embodiments of the present disclosure; 
         FIG. 6B  is a cross-sectional view showing a lens module according to some example embodiments of the present disclosure; 
         FIGS. 7A to 7D  are cross-sectional views showing shapes of lenses according to some example embodiments of the present disclosure; 
         FIG. 8  is an exploded perspective view showing an augmented reality providing device according to some example embodiments of the present disclosure; 
         FIG. 9  is a cross-sectional view showing an operation of the augmented reality providing device shown in  FIG. 8 ; 
         FIG. 10  is a plan view showing a display panel according to some example embodiments of the present disclosure; 
         FIG. 11  is a circuit diagram showing a pixel shown in  FIG. 10 ; and 
         FIG. 12  is a cross-sectional view showing a display panel according to some example embodiments of the present disclosure. 
     
    
    
     DETAILED DESCRIPTION 
     In the present disclosure, it will be understood that when an element or layer is referred to as being “on”, “connected to” or “coupled to” another element or layer, it can be directly on, connected or coupled to the other element or layer or intervening elements or layers may be present. 
     Like numerals refer to like elements throughout. In the drawings, the thickness, ratio, and dimension of components are exaggerated for effective description of the technical content. 
     As used herein, the term “and/or” includes any and all combinations of one or more of the associated listed items. 
     It will be understood that, although the terms first, second, etc. may be used herein to describe various elements, components, regions, layers and/or sections, these elements, components, regions, layers and/or sections should not be limited by these terms. These terms are only used to distinguish one element, component, region, layer or section from another region, layer or section. Thus, a first element, component, region, layer or section discussed below could be termed a second element, component, region, layer or section without departing from the teachings of the present disclosure. 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. 
     Spatially relative terms, such as “beneath”, “below”, “lower”, “above”, “upper” and the like, may be used herein for ease of description to describe one element or feature&#39;s relationship to another element(s) or feature(s) as illustrated in the figures. 
     Unless otherwise defined, all terms (including technical and scientific terms) used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this disclosure belongs. It will be further understood that terms, such as those defined in commonly used dictionaries, should be interpreted as having a meaning that is consistent with their meaning in the context of the relevant art and will not be interpreted in an idealized or overly formal sense unless expressly so defined herein. 
     It will be further understood that the terms “includes” and/or “including”, when used in this specification, specify the presence of stated features, integers, steps, operations, elements, and/or components, but do not preclude the presence or addition of one or more other features, integers, steps, operations, elements, components, and/or groups thereof. 
     Hereinafter, the present disclosure will be explained in detail with reference to the accompanying drawings. 
       FIG. 1  is a perspective view showing an electronic device  300  including an augmented reality providing device according to some example embodiments of the present disclosure. 
     Referring to  FIG. 1 , the electronic device  300  providing a user with an augmented reality image may have a shape, which is mounted on a user&#39;s head. For example, the electronic device  300  may be an eyeglasses-type device. The electronic device  300  may include a first display device  100   a , a second display device  100   b , and a frame  200  coupling the first display device  100   a  and the second display device  100   b.    
     The first display device  100   a  may include a first augmented reality providing device providing the augmented reality image to a right eye of the user, and the second display device  100   b  may include a second augmented reality providing device providing the augmented reality image to a left eye of the user. The first and second augmented reality providing devices  100   a  and  100   b  may have substantially the same shape as each other. 
     The frame  200  is coupled to each of the first and second augmented reality providing devices  100   a  and  100   b  and protects the first and second augmented reality providing devices  100   a  and  100   b . The frame  200  may have a shape that is worn by the user.  FIG. 1  shows the eyeglasses-type electronic device  300 , however, the electronic device  300  should not be limited to the eyeglasses-type. That is, the electronic device  300  may be implemented in various forms that may be worn by the user, such as a band type. 
     The first and second augmented reality providing devices  100   a  and  100   b  have substantially the same shape as each other and operate with the same driving principle. Hereinafter, the augmented reality providing device described with reference to figures may be applied to both of the first and second augmented reality providing devices  100   a  and  100   b.    
       FIG. 2  is an exploded perspective view showing an augmented reality providing device  100  according to some example embodiments of the present disclosure. 
     Referring to  FIG. 2 , the augmented reality providing device  100  according to some example embodiments of the present disclosure includes a lens module LM and a display module DM. 
     The lens module LM includes a lens LS and reflective modules RM 1  to RM 4 . The lens LS may be formed to be transparent or semi-transparent using a glass or plastic material. Accordingly, the user may see a real image through the lens LS. The lens LS may have a refractive power (e.g., a predetermined refractive power) according to a user&#39;s eyesight. 
     The lens LS may have a decahedral shape defined by two bottom surfaces ES and FS and side surfaces connecting the two bottom surfaces ES and FS. However, the shape of the lens LS should not be limited thereto or thereby, and the lens LS may have various shapes. For example, the lens LS may have a polyhedral shape defined by two bottom surfaces, each having a polygonal shape, and side surfaces connecting the two bottom surfaces. In addition, the lens LS may have various shapes, such as a cylindrical shape, an elliptical shape, a semi-cylindrical shape, and a semi-elliptical shape rather than the polyhedral shape. 
     At least one side surface among the side surfaces of the lens LS may have a multi-sided structure. The at least one side surface having the multi-sided structure may be located adjacent to the display module DM and may receive an image from the display module DM. Accordingly, hereinafter, the side surface will be referred to an “incident surface IS”. That is, the incident surface IS may have the multi-sided structure. The incident surface IS may include a plurality of surfaces arranged in a first direction DR 1 . The incident surface IS may extend in a second direction DR 2  perpendicular to the first direction DR 1 . 
     The lens module LM includes the reflective modules RM 1  to RM 4 . The reflective modules RM 1  to RM 4  may be arranged in the second direction DR 2  along the incident surface IS. In  FIG. 2 , the lens module LM includes first to fourth reflective modules RM 1  to RM 4 , however, the number of the reflective modules RM 1  to RM 4  should not be limited thereto or thereby. Each of the reflective modules RM 1  to RM 4  includes a plurality of reflective mirrors RIM 1  to RIM 3  (refer to  FIG. 3 ). The reflective mirrors RIM 1  to RIM 3  are arranged in the first direction DR 1 . As a representative example of the present disclosure, each of the reflective modules RM 1  to RM 4  includes first to third reflective mirrors RIM 1  to RIM 3 , however, the number of the reflective mirrors RIM 1  to RIM 3  should not be limited thereto or thereby. 
     The reflective mirrors RIM 1  to RIM 3  reflect a virtual image displayed through the display module DM to be focused on a retina of the user&#39;s eye HE. Accordingly, although the user focuses on the real image through the lens LM, the user may clearly see the virtual image. That is, the user may clearly see the virtual image even though the user does not shift the focus on the real image. 
     Each of the reflective mirrors RIM 1  to RIM 3  may have a size smaller than a size of a pupil. As an example, each of the reflective mirrors RIM 1  to RIM 3  may have a diameter of about 4 mm or less. In this case, because the user focuses on the real image, it is difficult for the user to recognize the reflective mirrors RIM 1  to RIM 3 . However, as the size of each of the reflective mirrors RIM 1  to RIM 3  decreases, a brightness of the virtual image provided to the user&#39;s eye HE by the display module DM may be reduced. Therefore, the size of the reflective mirrors RIM 1  to RIM 3  may be set by taking into account the above-mentioned aspects. 
     When the size of the reflective mirrors RIM 1  to RIM 3  is smaller than the size of the pupil, the reflective mirrors RIM 1  to RIM 3  have a pinhole effect. Therefore, each of the first to third reflective mirrors RIM 1  to RIM 3  may be referred to as a “pin mirror”. When the virtual image displayed through the display module DM is reflected by the reflective mirrors RIM 1  to RIM 3 , a depth of field becomes deep. 
     As an example, the first to third reflective mirrors RIM 1  to RIM 3  may include a metal material having a high reflectance, such as silver (Ag). In  FIG. 3 , each of the reflective mirrors RIM 1  to RIM 3  has a circular plate shape, however, each of the reflective mirrors RIM 1  to RIM 3  may have an oval or polygonal plate shape rather than the circular plate shape. In addition, according to some example embodiments, each of the reflective mirrors RIM 1  to RIM 3  may have a curved shape. 
     The number of the reflective modules RM 1  to RM 4  included in the lens module LM and the number of the reflective mirrors RIM 1  to RIM 3  included in each of the reflective modules RM 1  to RM 4  may increase to widen an area of the display module DM viewed to the user&#39;s eye HE, that is, a field of view (FOV) of the user. 
     The display module DM displays the virtual image to implement the augmented reality. The display module DM may be located adjacent to the incident surface IS of the lens LM, and the image displayed through the display module DM may be provided to the lens module LM through the incident surface IS. 
     The display module DM may have a flexibility, and thus may be bent. As an example, the display module DM may be a flexible organic light emitting display. 
     In  FIG. 2 , the display module DM is located on the one side surface among the side surfaces of the lens LS, however, the present disclosure should not be limited thereto or thereby. That is, the display module DM may be located on two or more side surfaces of the lens LS. In this case, the display module DM may include a plurality of display parts that display the image. 
     A functional module may be further located between the display module DM and the incident surface IS of the lens LS. For example, the functional module may include at least one layer with a light condensing function, an anti-reflection function, and an adhesive function. 
       FIG. 3  is a cross-sectional view showing an operation of the augmented reality providing device shown in  FIG. 2 ,  FIG. 4A  is a view showing a state before coupling of the display module to a lens module shown in  FIG. 3 , and  FIG. 4B  is a view showing a state in which the display module is coupled to the lens module of  FIG. 4A . 
     Referring to  FIG. 3 , the lens LS may include an exiting surface ES that emits an image reflected by the reflective mirrors RIM 1  to RIM 3  and a facing surface FS facing the exiting surface ES. The exiting surface ES and the facing surface FS may be connected to each other by the side surfaces. The display module DM is located adjacent to one side surface among the side surfaces of the lens LS. The one side surface is defined as the incident surface IS into which the virtual image displayed through the display module DM is incident. That is, the image output from the display module DM is provided to the lens module LM through the incident surface IS. 
     The incident surface IS includes at least one inclination surface. As an example, the incident surface IS includes a reference surface SS 1 , a first inclination surface SS 2 , and a second inclination surface SS 3 . 
     The reference surface SS 1  may be substantially vertical to the exiting surface ES and the facing surface FS. One side portion of the reference surface SS 1  may be connected to the facing surface FS. The first inclination surface SS 2  may be inclined with respect to the reference surface SS 1 , and one side portion thereof may be connected to the reference surface SS 1 . The second inclination surface SS 3  may be inclined with respect to the reference surface SS 1 , one side portion thereof may be connected to the first inclination surface SS 2 , and the other side portion thereof may be connected to the exiting surface ES. The first and second inclination surfaces SS 2  and SS 3  may be located between the exiting surface ES and the reference surface SS 1 . 
       FIGS. 3 to 4B  show the structure in which two inclination surfaces SS 2  and SS 3  are located between the exiting surface ES and the reference surface SS 1  as a representative example, however, they should not be limited thereto or thereby. That is, one inclination surface or three or more inclination surfaces may be located between the exiting surface ES and the reference surface SS 1 . 
     The first inclination surface SS 2  is inclined at a first angle θ 1  toward the reference surface SS 1 , and the second inclination surface SS 3  is inclined at a second angle θ 2  toward the reference surface SS 1 . The first angle θ 1  and the second angle θ 2  may be different from each other. As an example, the second angle θ 2  may be greater than the first angle θ 1 . 
     As shown in  FIGS. 2 and 4A , the display module DM is located adjacent to the incident surface IS. A width W 1  in the first direction DR 1  of the display module DM may be greater than a width W 2  in the first direction DR 1  of the lens LS. That is, when the display module DM is unfolded in the first direction DR 1  before the display module DM is coupled to the lens LS, the width W 1  of the display module DM is greater than the width W 2  of the lens LS. 
     As shown in  FIGS. 3 and 4B , when the display module DM is coupled to the lens LS, the display module DM may be located to correspond to the reference surface SS 1  and the first and second inclination surfaces SS 2  and SS 3 . That is, the display module DM may be bent along the reference surface SS 1  and the first and second inclination surfaces SS 2  and SS 3 . 
     As an example, the display module DM includes a first display area DA 1 , a second display area DA 2 , and a third display area DA 3 . The first display area DA 1  is located to correspond to the reference surface SS 1  of the incident surface IS. The second display area DA 2  is bent at a third angle θ 3  from the first display area DA 1  and located to correspond to the first inclination surface SS 2  of the incident surface IS. The third display area DA 3  is bent at a fourth angle θ 4  from the second display area DA 2  and located to correspond to the second inclination surface SS 3  of the incident surface IS. In the present example embodiment, the third angle θ 3  may be substantially the same as the first angle θ 1 , and the fourth angle θ 4  may be substantially the same as the second angle θ 2 . 
     As described above, because the display module DM is coupled to the lens module LM in a bent shape along the incident surface IS having the multi-sided structure, the entire of the image displayed through the display module DM may be provided to the user&#39;s eye HE without the need to increase the width, i.e., a thickness, of the lens LS even though the display module DM having the width larger than the width of the lens LS is employed. Accordingly, the field of view (FOV) of the user may be widened while preventing the thickness of the augmented reality providing device  100  from increasing. 
     Referring to  FIG. 3  again, the first reflective module RM 1  includes the first to third reflective mirrors RIM 1  to RIM 3 . The first to third reflective mirrors RIM 1  to RIM 3  are located to be spaced apart from each other. The first reflective mirror RIM 1  reflects a first image IM 1  incident through the reference surface SS 1  to the exiting surface ES. The second reflective mirror RIM 2  reflects a second image IM 2  incident through the first inclination surface SS 2  to the exiting surface ES. The third reflective mirror RIM 3  reflects a third image IM 3  incident through the second inclination surface SS 3  to the exiting surface ES. 
     The first reflective mirror RIM 1  may be located to be inclined at a fifth angle θ 5  with respect to the facing surface FS, and the second reflective mirror RIM 2  may be located to be inclined at a sixth angle θ 6  with respect to the facing surface FS. The third reflective mirror RIM 3  may be located to be inclined at a seventh angle θ 7  with respect to the facing surface FS. In this case, the fifth to seventh angles θ 5  to θ 7  may have different values from each other. 
     The first image IM 1  exiting from the first display area DA 1  is directly and mostly provided to the first reflective mirror RIM 1  after passing through the reference surface SS 1 . That is, most of the first image IM 1  is directly provided to the first reflective mirror RIM 1  without being refracted by the facing surface FS and the exiting surface ES. The fifth angle θ 5  may be set to allow the first image IM 1  incident into the first reflective mirror RIM 1  to be incident into the user&#39;s eye HE at maximum. As an example, the fifth angle θ 5  may be about 45°. 
     Meanwhile, most of the second image IM 2  exiting from the second display area DA 2  is provided to the second reflective mirror RIM 2  after being totally reflected by the facing surface FS and the exiting surface ES. The sixth angle θ 6  may be set to allow the second image IM 2  internally reflected by the lens LS to be provided to the user&#39;s eye HE by the second reflective mirror RIM 2  at maximum. The sixth angle θ 6  may be changed depending on the first angle θ 1  of the first inclination surface SS 2  and a refractive index of the lens LS. 
     Most of the third image IM 3  exiting from the third display area DA 3  is provided to the third reflective mirror RIM 3  after being totally reflected by the facing surface FS and the exiting surface ES. The seventh angle θ 7  may be set to allow the third image IM 3  internally reflected by the lens LS to be provided to the user&#39;s eye HE by the third reflective mirror RIM 3  at maximum. The seventh angle θ 7  may be changed depending on the second angle θ 2  of the second inclination surface SS 3  and the refractive index of the lens LS. 
     As described above, the fifth to seventh angles θ 5  to θ 7  may be set to provide the images IM 1  to IM 3  provided from corresponding display areas DA 1  to DA 3  to the user&#39;s eye HE. In addition, distances between the reflective mirrors RIM 1  to RIM 3  may be changed. That is, the reflective mirrors RIM 1  to RIM 3  are spaced at regular intervals in  FIG. 3 , however, they should not be limited thereto or thereby. The distances between the reflective mirrors RIM 1  to RIM 3  may be set to provide the images IM 1  to IM 3  provided from the corresponding display areas DA 1  to DA 3  to the user&#39;s eye HE. 
     Each of the reflective mirrors RIM 1  to RIM 3  allows the first to third images IM 1  to IM 3 , which are virtual images and displayed through the corresponding display areas DA 1  to DA 3  of the display module DM, to be focused at one point on the retina of the user&#39;s eye HE. Accordingly, even though the user focuses on the real image through the lens LS, the user may see the virtual image clearly. That is, although the user does not shift the focus on the real image, the user may see the virtual image clearly. 
     As described above, the structure in which the incident surface IS includes at least one inclination surface SS 2  and SS 3  has been described. One side portion of a lens body having a tetrahedral shape may be processed so as to form the lens LS provided with the at least one inclination surface SS 2  and SS 3  on the incident surface IS. As a method of processing the shape of the lens body, a wheel processing method, a laser processing method, an edge separation method by induction heating, or the like may be used. The at least one inclination surface SS 2  and SS 3  may be provided on the incident surface IS by the above-mentioned shape processing method. According to some example embodiments of the present disclosure, the at least one inclination surface SS 2  and SS 3  formed by the above-mentioned method may have a surface roughness equal to or smaller than about 10 nm. 
       FIG. 5A  is a view showing the first inclination surface shown in  FIG. 4A , and  FIG. 5B  is a view showing the second inclination surface shown in  FIG. 4A . 
     The reference surface SS 1 , which is not subjected to a shape processing treatment, may have the surface roughness of about 0.2 nm to 0.5 nm. As shown in  FIGS. 5A and 5B , the first and second inclination surfaces SS 2  and SS 3  formed through the shape fabrication process may have the surface roughness higher than that of the reference surface SS 1 . However, the surface roughness of the reference surface SS 1  and the first and second inclination surfaces SS 2  and SS 3  may be equal to or smaller than about 10 nm. As an example, the first and second inclination surfaces SS 2  and SS 3  may have the surface roughness of about 0.2 nm to 2 nm. 
     In addition, a fabricating process may be added to improve a surface roughness quality of the first and second inclination surfaces SS 2  and SS 3 . That is, a secondary fabrication process is performed on the first and second inclination surfaces SS 2  and SS 3  after the shape fabrication process, and thus the surface roughness of the first and second inclination surfaces SS 2  and SS 3  may be improved. 
       FIG. 6A  is a cross-sectional view showing a lens module according to some example embodiments of the present disclosure, and  FIG. 6B  is a cross-sectional view showing a lens module according to some example embodiments of the present disclosure. 
     Referring to  FIG. 6A , a lens module LM 1  may include a first lens LS 1 , a second lens LS 2 , and a reflective module RM. The reflective module RM may include a plurality of reflective mirrors RIM 1 , RIM 2 , and RIM 3  located between the first lens LS 1  and the second lens LS 2 . 
     The first lens LS 1  includes a first facing surface FS 1 , a first exiting surface ES 1 , and a plurality of first side surfaces connecting the first facing surface FS 1  and the first exiting surface ES 1 . One surface IS among the first side surfaces has a multi-sided structure. The display module DM (refer to  FIG. 3 ) is located adjacent to the one surface IS having the multi-sided structure. The one surface IS may be an incident surface receiving the image from the display module DM. Among the first side surfaces, an opposite surface FES opposite to the incident surface IS may have a curved structure. The opposite surface FES may be a first coupling surface coupled to the second lens LS 2 . 
     The second lens LS 2  includes a second facing surface FS 2 , a second exiting surface ES 2 , and a plurality of second side surfaces connecting the second facing surface FS 2  and the second exiting surface ES 2 . One surface among the second side surfaces may be a second coupling surface SES coupled to the first lens LS 1 . The second coupling surface SES may have substantially the same curved structure as the first coupling surface FES. 
     The reflective mirrors RIM 1  to RIM 3  may be located between the first coupling surface FES and the second coupling surface SES. That is, the reflective mirrors RIM 1  to RIM 3  may be formed by providing a reflective material, such as a silver, on a surface of one of the first coupling surface FES and the second coupling surface SES. The reflective mirrors RIM 1  to RIM 3  may be formed by a depositing, printing, or coating process. 
     An adhesive layer AL may be further located between first coupling surface FES and the second coupling surface SES to couple the first lens LS 1  and the second lens LS 2 . The adhesive layer AL may be optically clear. The adhesive layer AL may be an adhesive layer manufactured by coating a liquid adhesive material and curing the liquid adhesive material or an adhesive sheet separately manufactured. For example, the adhesive layer AL may be a pressure sensitive adhesive (PSA), an optical clear adhesive (OCA), or an optical clear resin (OCR). 
     When the first and second lenses LS 1  and LS 2  are coupled to each other, the first and second facing surfaces FS 1  and FS 2  are connected to each other to form one facing surface FS, and the first and second exiting surfaces ES 1  and ES 2  are connected to each other to form one exiting surface ES. The facing surface FS formed by connecting the first and second facing surfaces FS 1  and FS 2  to each other corresponds to the facing surface FS shown in  FIG. 3 , and the exiting surface ES formed by connecting the first and second exiting surfaces ES 1  and ES 2  to each other corresponds to the exiting surface ES shown in  FIG. 3 . 
     A curvature of a coupling surface at which the reflective mirrors RIM 1  to RIM 3  are formed may vary depending on an inclination angle of first and second inclination surfaces SS 2  and SS 3 . In a case where the reflective mirrors RIM 1  to RIM 3  are formed on the second coupling surface SES, the second coupling surface SES may be divided into a first area A 1  in which the first reflective mirror RIM 1  is located, a second area A 2  in which the second reflective mirror RIM 2  is located, and a third area A 3  in which the third reflective mirror RIM 3  is located. The curvatures of the second coupling surface SES in the first to third areas A 1  to A 3  may be different from each other, and particularly, the curvatures of the second coupling surface SES in the second and third areas A 2  and A 3  may vary depending on the inclination angles of the first and second inclination surfaces SS 2  and SS 3 . The first coupling surface FES may have substantially the same shape as the second coupling surface SES. 
     Referring to  FIG. 6B , each of the first coupling surface FES of the first lens LS 1  and the second coupling surface SES of the second lens LS 2  may have the multi-sided structure. As an example, the first coupling surface FES may include a first sub-coupling surface S 1 , a second sub-coupling surface S 2 , and a third sub-coupling surface S 3 . The second coupling surface SES may include a fourth sub-coupling surface S 4 , a fifth sub-coupling surface S 5 , and a sixth sub-coupling surface S 6 . Angles between each of the first sub-coupling surface S 1 , the second sub-coupling surface S 2 , and the third sub-coupling surface S 3  and the first facing surface FS 1  may be different from each other. Similarly, angles between each of the fourth sub-coupling surface S 4 , the fifth sub-coupling surface S 5 , and the sixth sub-coupling surface S 6  and the second facing surface FS 2  may be different from each other. 
     The reflective mirrors RIM 1  to RIM 3  may be located between the first coupling surface FES and the second coupling surface SES. That is, the reflective mirrors RIM 1  to RIM 3  may be formed by providing a reflective material, such as a silver, on a surface of one of the first and the second coupling surfaces FES and SES. In a case where the reflective mirrors RIM 1  to RIM 3  are formed on the second coupling surface SES, the first reflective mirror RIM 1  may be formed on the fourth sub-coupling surface S 4 , the second reflective mirror RIM 2  may be formed on the fifth sub-coupling surface S 5 , and the third reflective mirror RIM 3  may be formed on the sixth sub-coupling surface S 6 . 
     Angles R_θ 1 , R_θ 2 , and R_θ 3  between each of the fourth sub-coupling surface S 4 , the fifth sub-coupling surface S 5 , and the sixth sub-coupling surface S 6  and the second facing surface FS 2  may vary depending on the inclination angles of the first and second inclination surfaces SS 2  and SS 3 . Particularly, the angles R_θ 2 , and R_θ 3  between the fifth and sixth sub-coupling surfaces S 5  and S 6  and the second facing surface FS 2  may vary depending on the inclination angles of the first and second inclination surfaces SS 2  and SS 3 . 
     In the present example embodiment, the structure in which the first coupling surface FES has substantially the same shape as the second coupling surface SES is shown, however, it should not be limited thereto or thereby. For example, the first coupling surface FES may have the curved shape different from the second coupling surface SES. 
       FIG. 7A  is a cross-sectional view showing a shape of a lens LS 3  according to some example embodiments of the present disclosure. 
     Referring to  FIG. 7A , an incident surface IS 3  of the lens LS 3  according to some example embodiments of the present disclosure may have a curved structure. The incident surface IS 3  shown in  FIG. 7A  may have a generally curved shape while the incident surface IS shown in  FIGS. 3 to 4B  includes one or more inclination surfaces SS 2  and SS 3 . That is, the incident surface IS 3  may be formed by curving two surfaces, i.e., one side surface and one bottom surface, of the lens body. As the curving processing method, a wheel processing method, a laser processing method, or the like may be used. 
     The display module DM may be located along the shape of the incident surface IS 3 . Accordingly, the display module DM having a width W 1  greater than a width W 2  of the lens LS 3  may be located on the incident surface IS 3 . That is, the incident surface IS 3  may receive an image from a display area having the width W 1  greater than the width W 2  of the lens LS 3 . Therefore, the FOV of the augmented reality providing device may be widened without increasing a thickness of the lens LS 3 . 
       FIG. 7B  is a cross-sectional view showing a shape of a lens LS 4  according to some example embodiments of the present disclosure, and  FIG. 7C  is a cross-sectional view showing a shape of a lens LS 5  according to some example embodiments of the present disclosure. 
     Referring to  FIG. 7B , an incident surface IS 4  of the lens LS 4  according to some example embodiments of the present disclosure may include three inclination surfaces SS 2 , SS 3 , and SS 4 . That is, the incident surface IS 4  may include a reference surface SS 1  and first to third inclination surfaces SS 2  to SS 4 . The first and second inclination surfaces SS 2  and SS 3  may be located between the reference surface SS 1  and the exiting surface ES, and the third inclination surface SS 4  may be located between the reference surface SS 1  and the facing surface FS. The third inclination surface SS 4  may be inclined at a predetermined angle with respect to the reference surface SS 1 , and the third inclination surface SS 4  may be inclined at an angle equal to or smaller than the inclined angle of the first inclination surface SS 2  with respect to the reference surface SS 1 . 
     According to some example embodiments, when the third inclination surface SS 4  is located on the incident surface IS 4 , each of the reflective modules RM 1  to RM 4  (refer to  FIG. 3 ) may further include a reflective mirror corresponding to the third inclination surface SS 4 . An angle of the reflective mirror corresponding to the third inclination surface SS 4  may be set to allow the image incident through the third inclination surface SS 4  to be provided to the user&#39;s eye HE (refer to  FIG. 3 ). 
     Referring to  FIG. 7C , an incident surface IS 5  of the lens LS 5  according to some example embodiments of the present disclosure may have a curved shape. Different from the incident surface IS 3  shown in  FIG. 7A , the incident surface IS 5  shown in  FIG. 7C  may be formed by curving three surfaces, i.e., one side surface and two bottom surfaces, of the lens body. As the curving processing method, a wheel processing method, a laser processing method, or the like may be used. Accordingly, a portion of the facing surface FS of the lens LS 3  of  FIG. 7A  may be included in the incident surface IS 5 . Thus, the incident surface IS 5  may have a width greater than that of the incident surface IS 3  of  FIG. 7A . 
     The display module DM may be located along the shape of the incident surface IS 5 . Accordingly, the display module DM having a width W 3  greater than a width W 2  of the lens LS 5  may be located on the incident surface IS 5 . That is, the incident surface IS 5  may receive an image from a display area having the width W 3  greater than the width W 2  of the lens LS 5 . Therefore, the FOV of the augmented reality providing device may be widened without increasing a thickness of the lens LS 5 . 
       FIG. 7D  is a cross-sectional view showing a shape of a lens LS 6  according to some example embodiments of the present disclosure. 
     Referring to  FIG. 7D , an incident surface IS 6  of the lens LS 6  according to some example embodiments of the present disclosure may include one or more curved surfaces CS 1  and CS 2 . As an example, the incident surface IS 6  includes a first curved surface CS 1  and a second curved surface CS 2 . 
     The first curved surface CS 1  may have a convex curved shape and, one side portion thereof may be connected to the facing surface FS. The second curved surface CS 2  may be recessed inward of the lens LS 6  to have a concave curved shape, one side portion thereof may be connected to the first curved surface CS 1 , and the other side portion thereof may be connected to the exiting surface ES. 
       FIG. 7D  shows the structure in which two curved surfaces CS 1  and CS 2  are located between the facing surface FS and the exiting surface ES as a representative example, however, it should not be limited thereto or thereby. That is, three or more curved surfaces may be located between the facing surface FS and the exiting surface ES. 
       FIG. 8  is an exploded perspective view showing an augmented reality providing device  105  according to some example embodiments of the present disclosure, and  FIG. 9  is a cross-sectional view showing an operation of the augmented reality providing device  105  shown in  FIG. 8 . 
     Referring to  FIGS. 8 and 9 , the augmented reality providing device  105  according to some example embodiments of the present disclosure includes a lens module LM, a first display module DM 1 , and a second display module DM 2 . 
     The lens module LM includes a lens DLS, a plurality of upper reflective modules RM 1  to RM 4 , and a plurality of lower reflective modules RM 5  to RM 8 . The lens DLS may be formed of a glass or plastic material to be transparent or semi-transparent. 
     The lens DLS may have a decahedron shape defined by two bottom surfaces ES and FS facing each other and side surfaces connecting the two bottom surfaces ES and FS. At least two side surfaces among the side surfaces of the lens DLS may have a multi-sided structure. One side surface of the at least two side surfaces having the multi-sided structure may be located adjacent to the first display module DM 1  and may receive an image from the first display module DM 1 . The other side surface of the at least two side surfaces having the multi-sided structure may be located adjacent to the second display module DM 2  and may receive an image from the second display module DM 2 . Accordingly, hereinafter, the side surface located adjacent to the first display module DM 1  will be referred to a “first incident surface UIS”, and the side surface located adjacent to the second display module DM 2  will be referred to a “second incident surface LIS”. That is, each of the first and second incident surfaces UIS and LIS may have the multi-sided structure. The first incident surface UIS may include a plurality of surfaces arranged in the first direction DR 1  and may extend in the second direction DR 2  perpendicular to the first direction DR 1 . The second incident surface LIS may include a plurality of surfaces arranged in the first direction DR 1  and may extend in the second direction DR 2  to be parallel to the first incident surface UIS. 
     The first display module DM 1  displays a virtual image to implement the augmented reality. The first display module DM 1  is located adjacent to the first incident surface UIS of the lens DLS, and the image displayed through the first display module DM 1  is provided to the lens module LM through the first incident surface UIS. The second display module DM 2  displays a virtual image to implement the augmented reality. The second display module DM 2  is located adjacent to the second incident surface LIS of the lens DLS, and the image displayed through the second display module DM 2  is provided to the lens module LM through the second incident surface LIS. 
     The upper reflective modules RM 1  to RM 4  may be arranged in the second direction DR 2  along the first incident surface UIS, and the lower reflective modules RM 5  to RM 8  may be arranged in the second direction DR 2  along the second incident surface LIS.  FIG. 8  shows the structure in which the lens module LM includes four upper reflective modules RM 1  to RM 4  and four lower reflective modules RM 5  to RM 8 , however, the number of the reflective modules RM 1  to RM 8  should not be limited thereto or thereby. 
     Each of the upper reflective modules RM 1  to RM 4  includes a plurality of upper reflective mirrors URIM 1  to URIM 3 , and each of the lower reflective modules RM 5  to RM 8  includes a plurality of lower reflective mirrors LRIM 1  to LRIM 3 . The upper reflective mirrors URIM 1  to URIM 3  are arranged in the first direction DR 1 . The upper reflective mirrors URIM 1  to URIM 3  are arranged to become closer to the second incident surface LIS as going in the first direction DR 1 . The lower reflective mirrors LRIM 1  to LRIM 3  are arranged in the first direction DR 1 . The lower reflective mirrors LRIM 1  to LRIM 3  are arranged to become closer to the first incident surface UIS as going in the first direction DR 1 . 
     As an example, each of the reflective modules RM 1  to RM 8  includes three reflective mirrors, however, the number of the reflective mirrors should not be limited thereto or thereby. 
     The upper reflective mirrors URIM 1  to URIM 3  are located to reflect a virtual image displayed through the first display module DM 1  and to allow the virtual image to be focused at one point on the retina of the user&#39;s eye HE. The lower reflective mirrors LRIM 1  to LRIM 3  are located to reflect a virtual image displayed through the second display module DM 2  and to allow the virtual image to be focused at one point on the retina of the user&#39;s eye HE. 
     As described above, in the case where the user receives the virtual image from two display modules DM 1  and DM 2 , the FOV of the augmented reality providing device  105  may be widened. 
     Referring to  FIG. 9 , the first incident surface UIS may include at least one inclination surface. As an example, the first incident surface UIS may include an upper reference surface USS 1 , a first upper inclination surface USS 2 , and a second upper inclination surface USS 2 . 
     The upper reference surface USS 1  may be a surface substantially perpendicular to the exiting surface ES and the facing surface FS. One side portion of the upper reference surface USS 1  may be connected to the facing surface FS. The first upper inclination surface USS 2  may be inclined with respect to the upper reference surface USS 1 , and one side portion of the first upper inclination surface USS 2  may be connected to the upper reference surface USS 1 . The second upper inclination surface USS 3  may be inclined with respect to the upper reference surface USS 1 , one side portion of the second upper inclination surface USS 3  may be connected to the first upper inclination surface USS 2 , and the other side portion of the second upper inclination surface USS 3  may be connected to the exiting surface ES. The first and second upper inclination surfaces USS 2  and USS 3  may be located between the exiting surface ES and the upper reference surface USS 1 . 
     The second incident surface LIS may be located at an opposite side to the first incident surface UIS and may include at least one inclination surface. As an example, the second incident surface LIS may include a lower reference surface LSS 1 , a first lower inclination surface LSS 2 , and a second lower inclination surface LSS 3 . 
     The lower reference surface LSS 1  may be a surface substantially perpendicular to the exiting surface ES and the facing surface FS. One side portion of the lower reference surface LSS 1  may be connected to the facing surface FS. The first lower inclination surface LSS 2  may be inclined with respect to the lower reference surface LSS 1 , and one side portion of the first lower inclination surface LSS 2  may be connected to the lower reference surface LSS 1 . The second lower inclination surface LSS 3  may be inclined with respect to the lower reference surface LSS 1 , one side portion of the second lower inclination surface LSS 3  may be connected to the first lower inclination surface LSS 2 , and the other side portion of the second lower inclination surface LSS 3  may be connected to the exiting surface ES. The first and second lower inclination surfaces LSS 2  and LSS 3  may be located between the exiting surface ES and the lower reference surface LSS 1 . 
     In  FIGS. 8 and 9 , the structure of each of the first and second incident surfaces UIS and LIS should not be limited thereto or thereby. That is, each of the first and second incident surfaces UIS and LIS may have the shapes of the incident surfaces shown in  FIGS. 7A to 7D . In addition, the first and second incident surfaces UIS and LIS have substantially the same shape as each other in the present example embodiment, however, they should not be limited thereto or thereby. That is, the first and second incident surfaces UIS and LIS may have different shapes from each other. 
     Since the shape of the first and second incident surfaces UIS and LIS is the same as the shape of the incident surface IS shown in  FIG. 3 , detailed descriptions of the first and second incident surfaces UIS and LIS will be omitted. 
     A width W 1  in the first direction DR 1  of the first and second display modules DM 1  and DM 2  may be greater than a width W 2  in the first direction DR 1  of the lens DLS. That is, when the first and second display modules DM 1  and DM 2  are unfolded in the first direction DR 1  before the first and second display modules DM 1  and DM 2  are coupled to the lens DLS, the width W 1  of the first and second display modules DM 1  and DM 2  is greater than the width W 2  of the lens DLS. 
     The first and second display modules DM 1  and DM 2  may have a flexibility and thus may be bent. For example, each of the first and second display modules DM 1  and DM 2  may be a flexible organic light emitting display device. 
     As shown in  FIG. 9 , when the first and second display modules DM 1  and DM 2  are coupled to the lens DLS, the first display module DM 1  is bent along the first incident surface UIS, and the second display module DM 2  is bent along the second incident surface LIS. That is, the first and second display modules DM 1  and DM 2  may be located corresponding to the shape of the first and second incident surfaces UIS and LIS. Accordingly, the first and second display modules DM 1  and DM 2  having the width W 1  greater than the width W 2  of the lens DLS may be respectively located on the first and second incident surfaces UIS and LIS. Thus, the FOV of the augmented reality providing device  105  may be widened without increasing a thickness of the lens DLS. 
       FIG. 10  is a plan view showing a display panel according to some example embodiments of the present disclosure,  FIG. 11  is a circuit diagram showing a pixel shown in  FIG. 10 , and  FIG. 12  is a cross-sectional view showing a display panel according to some example embodiments of the present disclosure. 
     Referring to  FIGS. 10 to 12 , a display module DM may include a display panel DP. The display panel DP may include a display area DA and a non-display area NDA when viewed in a plan view. In the present example embodiment, the non-display area NDA is defined along an edge of the display area DA. 
     The display panel DP includes a driving circuit GDC, a plurality of signal lines GL, DL, and PL and a plurality of pixels PX. The pixels PX are arranged in the display area DA. Each of the pixels PX includes an organic light emitting diode OLED and a pixel driving circuit PDC connected to the organic light emitting diode OLED. The driving circuit GDC, the signal lines GL, DL, and PL, and the pixel driving circuit PDC may be included in a circuit element layer DP-CL shown in  FIG. 12 . 
     The driving circuit GDC includes a shift register. The shift register includes a plurality of stages, each of which generates a plurality of scan signals, and sequentially outputs the scan signals to a plurality of scan lines GL described later. As another example, the driving circuit GDC may further output another control signal to the pixel driving circuit PDC. 
     The driving circuit GDC may include a plurality of thin film transistors formed through the same process as the pixel driving circuit PDC, e.g., a low temperature polycrystalline silicon (LTPS) process or a low temperature polycrystalline oxide (LTPO) process. 
     The signal lines GL, DL, and PL include the scan lines GL, data lines DL, and a power line PL. Each of the scan lines GL is connected to a corresponding pixel PX among the pixels PX, and each of the data lines DL is connected to a corresponding pixel PX among the pixels PX. The power line PL is connected to the pixels PX. 
     The display module DM includes a circuit board FCB connected to the display panel DP and a driving chip D-IC mounted on the circuit board FCB. The circuit board FCB may be a flexible printed circuit board. The display module DM further includes a main circuit board MCB, and the main circuit board MCB connects to the display panel DP through the circuit board FCB. 
     In the present example embodiment, a chip-on-film (COF) structure in which the driving chip D-IC is mounted on the circuit board FCB is shown, however, it should not be limited thereto or thereby. For example, the display module DM may have a chip-on-panel (COP) structure in which the driving chip D-IC is mounted on the display panel DP. 
       FIG. 11  shows the pixel PX connected to one scan line GL, one data line DL, and the power line PL as a representative example. A configuration of the pixel PX may be changed without being limited thereto or thereby. 
     The organic light emitting diode OLED may be a front surface light emitting type diode or a rear surface light emitting type diode. The pixel PX includes a first transistor T 1  (or a “switching transistor”), a second transistor T 2  (or a “driving transistor”), and a capacitor Cst as the pixel driving circuit PDC to drive the organic light emitting diode OLED. A first power voltage ELVDD is applied to the second transistor T 2 , and a second power voltage ELVSS is applied to the organic light emitting diode OLED. The second power voltage ELVSS may be lower than the first power voltage ELVDD. 
     The first transistor T 1  outputs a data signal applied thereto through the data line DL in response to the scan signal applied thereto through the scan line GL. The capacitor Cst is charged with a voltage corresponding to the data signal provided from the first transistor T 1 . 
     The second transistor T 2  is connected to the organic light emitting diode OLED. The second transistor T 2  controls a driving current flowing through the organic light emitting diode OLED in response to an amount of electric charge charged in the capacitor Cst. The organic light emitting diode OLED emits a light during a turned-on period of the second transistor T 2 . 
       FIG. 11  shows a structure in which the pixel driving circuit PDC includes two transistors T 1  and T 2  and one capacitor Cst, however, the configuration of the pixel driving circuit PDC should not be limited thereto or thereby. 
     As shown in  FIG. 12 , in the display panel DP according to some example embodiments of the present disclosure, the circuit element layer DP-CL, a display element layer DP-OLED, and a thin film encapsulation layer TFE may be sequentially stacked on a base layer SUB. 
     The circuit element layer DP-CL includes at least one inorganic layer, at least one organic layer, and a circuit element. The circuit element layer DP-CL includes a buffer layer BFL that is the inorganic layer, a first intermediate inorganic layer  10 , a second intermediate inorganic layer  20 , and an intermediate organic layer  30  that is the organic layer. 
     The inorganic layers may include silicon nitride, silicon oxynitride, and silicon oxide. The organic layer may include at least one of an acrylic-based resin, a methacrylic-based resin, a polyisoprene-based resin, a vinyl-based resin, an epoxy-based resin, a urethane-based resin, a cellulose-based resin, a siloxane-based resin, a polyimide-based resin, a polyamide-based resin, and a perylene-based resin. The circuit element includes conductive patterns and/or semiconductor patterns. 
     The buffer layer BFL improves a coupling force between the base layer SUB and the conductive patterns or the semiconductor patterns. According to some example embodiments, a barrier layer may be further located on an upper surface of the base layer SUB to prevent foreign substances from entering. The buffer layer BFL and the barrier layer may be selectively located or omitted. 
     A semiconductor pattern OSP 1  (hereinafter, referred to as a “first semiconductor pattern”) of the first transistor T 1  and a semiconductor pattern OSP 2  (hereinafter, referred to as a “second semiconductor pattern”) of the second transistor T 2  are located on the buffer layer BFL. The first semiconductor pattern OSP 1  and the second semiconductor pattern OSP 2  may be selected from amorphous silicon, polycrystalline silicon, and metal oxide semiconductor. 
     The first intermediate inorganic layer  10  is located on the first semiconductor pattern OSP 1  and the second semiconductor pattern OSP 2 . A control electrode GE 1  (hereinafter, referred to as a “first control electrode”) of the first transistor T 1  and a control electrode GE 2  (hereinafter, referred to as a “second control electrode”) of the second transistor T 2  are located on the first intermediate inorganic layer  10 . The first control electrode GE 1  and the second control electrode GE 2  may be formed through the same photolithography process as the scan lines GL (refer to  FIGS. 10 and 11 ). 
     The second intermediate inorganic layer  20  is located on the first intermediate inorganic layer  10  to cover the first control electrode GE 1  and the second control electrode GE 2 . An input electrode DE 1  (hereinafter, referred to as a “first input electrode”) and an output electrode SE 1  (hereinafter, referred to as a “first output electrode”) of the first transistor T 1  and an input electrode DE 2  (hereinafter, referred to as a “second input electrode”) and an output electrode SE 2  (hereinafter, referred to as a “second output electrode”) of the second transistor T 2  are located on the second intermediate inorganic layer  20 . 
     The first input electrode DE 1  and the first output electrode SE 1  are connected to the first semiconductor pattern OSP 1  respectively through a first contact hole CH 1  and a second contact hole CH 2 , which are defined through the first intermediate inorganic layer  10  and the second intermediate inorganic layer  20 . The second input electrode DE 2  and the second output electrode SE 2  are connected to the second semiconductor pattern OSP 2  respectively through a third contact hole CH 3  and a fourth contact hole CH 4 , which are defined through the first intermediate inorganic layer  10  and the second intermediate inorganic layer  20 . Meanwhile, according to another embodiment of the present disclosure, a portion of the first transistor T 1  and the second transistor T 2  may be changed to a bottom gate structure. 
     The intermediate organic layer  30  is located on the second intermediate inorganic layer  20  to cover the first input electrode DE 1 , the second input electrode DE 2 , the first output electrode SE 1 , and the second output electrode SE 2 . The intermediate organic layer  30  may provide a flat surface. 
     The display element layer DP-OLED is located on the intermediate organic layer  30 . The display element layer DP-OLED includes a pixel definition layer PDL and the organic light emitting diode OLED. The pixel definition layer PDL includes an organic material as the intermediate organic layer  30 . A first electrode AE is located on the intermediate organic layer  30 . The first electrode AE is connected to the second output electrode SE 2  through a fifth contact hole CH 5  defined through the intermediate organic layer  30 . An opening OP is defined through the pixel definition layer PDL. At least a portion of the first electrode AE is exposed through the opening OP of the pixel definition layer PDL. 
     The pixel PX is located in a pixel area when viewed in a plan view. The pixel area includes a light emitting area PXA and a non-light emitting area NPXA located adjacent to the light emitting area PXA. The non-light emitting area NPXA surrounds the light emitting area PXA. In the present example embodiment, the light emitting area PXA is defined to correspond to a portion of the first electrode AE exposed through the opening OP. 
     A hole control layer HCL may be commonly located over the light emitting area PXA and the non-light emitting area NPXA. According to some example embodiments, a common layer like the hole control layer HCL may be commonly formed over the plural pixels PX. 
     A light emitting layer EML may be located on the hole control layer HCL. The light emitting layer EML may be located in an area corresponding to the opening OP. That is, the light emitting layer EML may be formed in each of the pixels PX after being divided into plural portions. The light emitting layer EML may include an organic material and/or an inorganic material. In the present example embodiment, the patterned light emitting layer EML is shown as a representative example, however according to another embodiment, the light emitting layer EML may be commonly located over the pixels PX. In this case, the light emitting layer EML may emit a white light. In addition, the light emitting layer EML may have a multi-layer structure. 
     An electron control layer ECL is located on the light emitting layer EML. According to some example embodiments, the electron control layer ECL may be commonly formed over the pixels PX. 
     A second electrode CE is located on the electron control layer ECL. The second electrode CE is commonly located over the pixels PX. 
     The thin film encapsulation layer TFE is located on the second electrode CE. The thin film encapsulation layer TFE is commonly located over the pixels PX. In the present example embodiment, the thin film encapsulation layer TFE directly covers the second electrode CE. According to some example embodiments of the present disclosure, a capping layer may be further located between the thin film encapsulation layer TFE and the second electrode CE to cover the second electrode CE. In this case, the thin film encapsulation layer TFE may directly cover the capping layer. 
       FIG. 12  shows an example of the display panel DP, and the display panel DP of the present disclosure should not be limited to the structure of  FIG. 12 . 
     Although aspects of some example embodiments of the present disclosure have been described, it is understood that the present disclosure should not be limited to these example embodiments but various changes and modifications can be made by one ordinary skilled in the art within the spirit and scope of the present disclosure as hereinafter claimed. 
     Therefore, the disclosed subject matter should not be limited to any single embodiment described herein, and the scope of the present inventive concept shall be determined according to the attached claims and their equivalents.