Patent Publication Number: US-2016239131-A1

Title: Circular touch panel and manufacturing method of the same

Description:
CROSS-REFERENCE TO RELATED APPLICATION 
     This application claims priority from and the benefit of Korean Patent Application No. 10-2015-0023359, filed on Feb. 16, 2015, which is hereby incorporated by reference for all purposes as if fully set forth herein. 
     BACKGROUND 
     1. Field 
     Exemplary embodiments relate to a circular touch panel and a manufacturing method of the same, and more particularly, to a circular touch panel configuring a circular display device and a manufacturing method of the same. 
     2. Discussion of the Background 
     In accordance with the development of wearable smart devices, e.g., smart watches, or the like, there has been an increased demand for circular display devices. As representative examples, a smart watch, smart glasses, or the like, which include a circular display panel, have been developed. The circular display device may be configured by employing a structure of a general quadrangular display device. A display panel of the general quadrangular display device includes a plurality of pixels disposed in a row and column form and displays an image to a user by transferring light emitted from the plurality of pixels. In this case, the pixels are generally configured in a quadrangular shape. When a circular display device is configured with quadrangular pixels, the plurality of quadrangular pixels are disposed in a step shape or sawtooth shape in order to configure a circular boundary region of the circular display device. Therefore, there is a problem that a user may observe an image which is not smooth at the circular boundary region. 
     The above information disclosed in this Background section is only for enhancement of understanding of the background of the inventive concept, and, therefore, it may contain information that does not form the prior art that is already known to a person of ordinary skill in the art. 
     SUMMARY 
     Exemplary embodiments relate to a circular touch panel and a manufacturing method of the same. 
     Additional features of the invention will be set forth in the description which follows, and in part will be apparent from the description, or may be learned by practice of the invention. 
     An exemplary embodiment discloses a circular touch panel disposed on a circular display panel including a plurality of pixels, the circular touch panel including: a plurality of sensing electrodes; a plurality of connection wirings connecting the plurality of sensing electrodes to a signal processing circuit; and an insulator insulating the plurality of sensing electrodes from each other. The circular touch panel includes a circular boundary region patterned in an optical pattern. 
     An exemplary embodiment discloses a manufacturing method of a circular touch panel, the manufacturing method including: forming a plurality of connection wirings by depositing and patterning a first metal layer on an insulating substrate; forming a plurality of sensing electrodes by depositing and patterning a second metal layer such that sensing electrodes disposed adjacent to the plurality of connection wirings are connected to the plurality of connection wirings, respectively; and forming and patterning an insulator so as to insulate the plurality of sensing electrodes. When at least one of the plurality of connection wirings, the plurality of sensing electrodes, and the insulator is patterned, an optical pattern is simultaneously patterned on a circular boundary region of the circular touch panel. 
     An exemplary embodiment also discloses a touch screen panel, including: a substrate including a curved boundary region; a plurality of sensing electrodes disposed on the substrate; a connection wiring connecting one of the plurality of sensing electrodes to a signal processing circuit; and an insulator disposed on the plurality of sensing electrodes. An optical pattern is disposed on the curved boundary region to change a light propagation direction. 
     An exemplary embodiment provides advantages capable of providing a smooth image to a user by creating an optical effect at a circular boundary region. 
     The foregoing general description and the following detailed description are exemplary and explanatory and are intended to provide further explanation of the claimed subject matter. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       The accompanying drawings, which are included to provide a further understanding of the inventive concept, and are incorporated in and constitute a part of this specification, illustrate exemplary embodiments of the inventive concept, and, together with the description, serve to explain principles of the inventive concept. 
         FIG. 1  is a drawing showing a stacked structure of a circular display device according to an exemplary embodiment. 
         FIG. 2  is a diagram illustrating a corresponding relationship between a circular display panel and a circular touch panel according to an exemplary embodiment. 
         FIG. 3A  and  FIG. 3B  are diagrams showing shapes in which an insulator of a circular boundary region of the circular touch panel is patterned in an optical pattern of a multiple-slit pattern according to an exemplary embodiment. 
         FIG. 4A  and  FIG. 4B  are diagrams showing shapes in which an insulator of a circular boundary region of a circular touch panel is patterned in an optical pattern of a mesh pattern according to an exemplary embodiment. 
         FIG. 5A  and  FIG. 5B  are diagrams showing shapes in which a first metal layer of a circular boundary region of a circular touch panel is patterned in an optical pattern of a multiple-slit pattern according to an exemplary embodiment. 
         FIG. 6A  and  FIG. 6B  are diagrams showing shapes in which a second metal layer of a circular boundary region of a circular touch panel is patterned in an optical pattern of a multiple-slit pattern according to an exemplary embodiment. 
         FIG. 7A , FIG,  7 B, and  FIG. 7C  are diagrams illustrating a manufacturing method of a circular touch panel of  FIG. 3  according to an exemplary embodiment. 
     
    
    
     DETAILED DESCRIPTION OF THE ILLUSTRATED EMBODIMENTS 
     In the following description, for the purposes of explanation, numerous specific details are set forth in order to provide a thorough understanding of various exemplary embodiments. It is apparent, however, that various exemplary embodiments may be practiced without these specific details or with one or more equivalent arrangements. In other instances, well-known structures and devices are shown in block diagram form in order to avoid unnecessarily obscuring various exemplary embodiments. 
     In the accompanying figures, the size and relative sizes of layers, films, panels, regions, etc., may be exaggerated for clarity and descriptive purposes. Also, like reference numerals denote like elements. 
     When an element or layer is referred to as being “on,” “connected to,” or “coupled to” another element or layer, it may be directly on, connected to, or coupled to the other element or layer or intervening elements or layers may be present. When, however, an element or layer is referred to as being “directly on,” “directly connected to,” or “directly coupled to” another element or layer, there are no intervening elements or layers present. For the purposes of this disclosure, “at least one of X, Y, and Z” and “at least one selected from the group consisting of X, Y, and Z” may be construed as X only, Y only, Z only, or any combination of two or more of X, Y, and Z, such as, for instance, XYZ, XYY, YZ, and ZZ. Like numbers refer to like elements throughout. As used herein, the term “and/or” includes any and all combinations of one or more of the associated listed items. 
     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 used to distinguish one element, component, region, layer, and/or section from another element, component, region, layer, and/or section. Thus, a first element, component, region, layer, and/or section discussed below could be termed a second element, component, region, layer, and/or section without departing from the teachings of the present disclosure. 
     Spatially relative terms, such as “beneath,” “below,” “lower,” “above,” “upper,” and the like, may be used herein for descriptive purposes, and, thereby, to describe one element or feature&#39;s relationship to another element(s) or feature(s) as illustrated in the drawings. Spatially relative terms are intended to encompass different orientations of an apparatus in use, operation, and/or manufacture in addition to the orientation depicted in the drawings. For example, if the apparatus in the drawings is turned over, elements described as “below” or “beneath” other elements or features would then be oriented “above” the other elements or features. Thus, the exemplary term “below” can encompass both an orientation of above and below. Furthermore, the apparatus may be otherwise oriented (e.g., rotated  90  degrees or at other orientations), and, as such, the spatially relative descriptors used herein interpreted accordingly. 
     The terminology used herein is for the purpose of describing particular embodiments and is not intended to be limiting. 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. Moreover, the terms “comprises,” “comprising,” “includes,” and/or “including,” when used in this specification, specify the presence of stated features, integers, steps, operations, elements, components, and/or groups thereof, but do not preclude the presence or addition of one or more other features, integers, steps, operations, elements, components, and/or groups thereof 
     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 is a part. 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. 
       FIG. 1  is a drawing showing a stacked structure of a circular display device according to an exemplary embodiment. 
     Referring to  FIG. 1 , a circular display device  10  is configured in a stacked structure including a window  100 , a circular touch panel  200 , a polarizing plate  300 , and a circular display panel  400 . 
     Although the above exemplary embodiment shows a configuration in which the circular touch panel  200  and the circular display panel  400  are separately formed, the circular touch panel  200  and the circular display panel  400  may be integrally formed based on an on-cell scheme, an in-cell scheme, or the like in various configurations. 
     The circular display panel  400  includes a plurality of pixels PX (see  FIG. 2 ) and the plurality of pixels emit light according to a grayscale of an input image. The light may be provided from a backlight unit and passes through the pixels PX. Further, an organic light emitting diode or other display panel structures may be configured in the circular display panel  400 . The plurality of pixels PX, each of which may be configured in a quadrangular shape, may be arranged in approximately a matrix form including rows and columns of pixels. A detailed description thereof will be provided with reference to  FIG. 2 . 
     As noted above, the circular display panel  400  may be an organic light emitting display panel including a plurality of organic light emitting diodes (OLED) and a liquid crystal display panel having an interposed liquid crystal layer. One or more exemplary embodiments will be described in relation to characteristics of the circular touch panel  200  and a kind of circular display panel  400  is not limited to the examples illustrated herein. 
     The window  100  may be formed of glass, synthesized resin, or the like for protecting the circular display device  10  and may be attached by interposing an adhesive layer (not shown). 
     Although  FIG. 1  illustrates a case in which the circular touch panel  200  is attached to the window  100  while being disposed close to the window  100 , positions of the polarizing plate  300  and the circular touch panel  200  may be exchanged with each other, and a configuration of the polarizing plate  300  may be omitted depending on a kind of display device. 
     The polarizing plate  300  shown in  FIG. 1  may be a circular polarizing plate, and in this case, the circular display panel  400  may be an organic light emitting display panel. More specifically, the organic light emitting display device generally includes a polarizer such as the circular polarizing plate, or the like, in order to prevent a decrease of a contrast ratio by an external light reflection. 
     However, in a case in which the circular display panel  400  is the liquid crystal display panel, linear polarizing plates having a polarizing axis of 90° may be disposed over and below the circular display panel  400 , respectively. The kind and the number of polarizing plates described above may be changed depending on a mode of the liquid crystal display panel. For example, a first linear polarizing plate may be disposed beneath the circular display panel  400  and a second linear polarizing plate may be disposed above the circular display panel  400 . Another layer may be configured between the circular display panel  400  and one of the first linear polarizing plate and the second linear polarizing plate. The transmission axis of the first linear polarizing plate and the transmission axis of the second linear polarizing plate may be perpendicular to each other so that the two axes form 90°. However, the degree formed by the two axes may be configured differently according to various configurations. 
     Therefore, the kind, the position, and the polarization types, and the number of polarizing plates  300  are not limited as such. 
       FIG. 2  is a diagram illustrating a corresponding relationship between a circular display panel and a circular touch panel according to an exemplary embodiment. 
     Referring to  FIG. 2 , the circular display panel  400  and the circular touch panel  200  are configured so as to be overlapped with each other.  FIG. 2  shows a case in which the outer circular boundary of the circular display panel  400  and the outer circular boundary of the circular touch panel  200  are matched to each other, but it is apparent to those skilled in the art that sizes of the outer circular boundaries of the circular display panel  400  and the circular touch panel  200  may be changed depending on a product design. For example, the outer circular boundary of the circular display panel  400  may also be larger or smaller than the outer circular boundary of the circular touch panel  200 . In such a configuration, the center of the circular display panel  400  and the center of the circular touch panel  200  may be configured to be overlapped. 
     According to the illustrated exemplary embodiment, the circular display panel  400  includes a plurality of quadrangular pixels PX. Although the quadrangular shape is illustrated as a general shape of a pixel PX, the plurality of pixels PX may be arranged regularly with each other while having a certain shape such as a pentagon, a hexagon, or the like. 
     In order to configure the circular display panel  400  by arranging the plurality of quadrangular pixels PX, a step shape or sawtooth shape appears at the outer circular boundary region  210 ,  410  as shown in  FIG. 2 . 
     The lower the resolution, the less smooth an image will appear to a user in the circular boundary region  210  for boundary pixels having a step shape, a saw-tooth shape, and the like. 
     To address such a problem, the circular boundary region  210  may be covered by a black matrix or other elements, but there is another problem that the size of a display area decreases and the thickness of the surrounding bezel needs to be thicker. 
     To address such problems, exemplary embodiments disclose a method of patterning the circular boundary region  210  by a predetermined optical pattern, in order to provide a smooth image display to the eyes of users while maintaining the size of the display area and a narrow bezel configuration. 
     Hereinafter, enlarged portions  220   a,    220   b,    220   c,  and  220   d  included in the portion  220  of the circular touch panel  200  will be described with reference to  FIGS. 3A to 7C . Such configurations may also be applicable to other portions of the circular boundary region  210 ,  410 . 
       FIG. 3A  and  FIG. 3B  are diagrams showing shapes in which an insulator of a circular boundary region of a circular touch panel is patterned in an optical pattern of a multiple-slit pattern according to an exemplary embodiment. 
     Referring to  FIG. 2 ,  FIG. 3A , and  FIG. 3B , the circular touch panel  200  includes a plurality of connection wirings  260 ,  261 ,  262 , and  263 , a plurality of first sensing electrodes  240  and  241 , a plurality of second sensing electrodes  250  and  251 , an insulator  230 , and a plurality of bridge electrodes  255 , which may be stacked on an insulating substrate  201 . 
     The stacked structure of the connection wirings, the sensing electrodes, the insulator, and the bridge electrodes shown in the exemplary embodiment may be changed while the electrical connection relationship thereof is maintained, and the exemplary embodiment shows the stacked structure and the connection relationship as an example. 
     The plurality of first sensing electrodes  240  and  241  may be each formed to extend in a first direction and the plurality of second sensing electrodes  250  and  251  may be each formed to extend in a second direction which is perpendicular to the first direction. 
     According to an exemplary embodiment, the circular touch panel  200  is shown as a mutual-capacitance type in which the first sensing electrodes  240  and  241  and the second sensing electrodes  250  and  251  form mutual-capacitances. 
     However, even if the circular touch panel  200  is the mutual-capacitance type, the circular touch panel  200  may have a form in which the first sensing electrodes  240  and  241  and the second sensing electrodes  250  and  251  face each other because the first sensing electrodes  240  and  241  and the second sensing electrodes  250  and  251  are formed on different layers, not the same layer, and the circular touch panel  200  may be configured as a self-capacitance type because the first sensing electrodes  240  and  241  and the second sensing electrodes  250  and  251  may be formed on the same layer or different layers. 
     The mutual-capacitance type illustrated in an exemplary embodiment is merely one exemplary embodiment and does not limit the scope of the present invention. 
     The plurality of first sensing electrodes  240  and  241  and the plurality of second sensing electrodes  250  and  251  may be formed of or include a transparent electrode, such as indium tin oxide (ITO), and may be formed in a mesh shape. In the case in which the first sensing electrodes  240  and  241  and the second sensing electrodes  250  and  251  are formed in the mesh shape, the first sensing electrodes  240  and  241  and the second sensing electrodes  250  and  251  may be configured to include an opaque metal. In an exemplary embodiment, the material configuring the plurality of first sensing electrodes  240  and  241  and the plurality of second sensing electrodes  250  and  251  may be referred to as a second metal layer. 
     The plurality of connection wirings  260 ,  262 ,  263 , and  261  may be disposed at an outer portion of the insulating substrate  201  and electrically connect the plurality of first sensing electrodes  240  and  241  and the plurality of second sensing electrodes  250  and  251  to a signal processing circuit (not shown) configured to process a touch signal, respectively. For example, if a user touches the circular touch panel  200 , the signal processing circuit may recognize the touch and generate a touch signal. 
     The plurality of connection wirings  260 ,  261 ,  262 , and  263  may be disposed to surround an outer portion of the circular touch panel  200  as shown in  FIG. 3A . Accordingly, since the plurality of connection wirings  260 ,  261 ,  262 , and  263  are formed so as not to be overlapped with the display area, the plurality of connection wirings  260 ,  261 ,  262 , and  263  may be configured of an opaque low resistance metal. The plurality of connection wirings  260 ,  261 ,  262 , and  263  may be configured of a single or composite material, such as silver (Ag), copper (Cu), chromium (Cr), aluminum (Al), molybdenum/aluminum/molybdenum (Mo/Al/Mo), or the like. In various configurations, the plurality of connection wirings  260 ,  261 ,  262 , and  263  may include a transparent material. In an exemplary embodiment, the material configuring the plurality of connection wirings  260 ,  261 ,  262 , and  263  may be referred to as a first metal layer if the connection wirings  260 ,  261 ,  262 , and  263  include a single or composite material, such as silver (Ag), copper (Cu), chromium (Cr), aluminum (Al), molybdenum/aluminum/molybdenum (Mo/Al/Mo), or the like, or a metal other than the materials listed above. 
     The plurality of first sensing electrodes  240  and  241  may be each formed to be integrally extended in the first direction. In the case in which the plurality of second sensing electrodes  250  and  251  are formed on the same layer as that of the plurality of first sensing electrodes  240  and  241 , the plurality of second sensing electrodes  250  and  251  may be formed in an island-type for insulation with the plurality of first sensing electrodes  240  and  241 . 
     Therefore, in order for each of the plurality of second sensing electrodes  250  and  251  to extend in the second direction, the bridge electrode  255  may be used to connect the isolated second sensing electrodes  250  and  251 . In order to prevent the bridge electrode  255  and the first sensing electrodes  240  and  241  from being electrically connected to each other, the insulator  230  may be interposed therebetween. 
     The insulator  230  may be patterned to have a via-hole so that the bridge electrode  255  connects adjacent two of the second sensing electrodes of the island-type to each other. However, the insulator  230  itself may be patterned in the island-type depending on a kind of circular touch panel  200 , and this may be changed depending on different product configurations. 
     Both in the case in which the insulator  230  is patterned in the island-type and in the case in which the insulator  230  is patterned to have the via-hole, at least one patterning process may need to be performed. 
     According to the illustrated exemplary embodiment, an optical pattern may be patterned together on the circular boundary region  210  during the patterning process. Therefore, an optical effect may be obtained without adding a separate material deposition process or a separate patterning process. Further, the optical pattern in the circular boundary region  210  may include a material substantially identical to a material used for forming at least one of the plurality of the insulator  230 , and the plurality of connection wirings  260 ,  261 ,  262 , and  263 , and sensing electrodes  240  (see e.g.,  FIG. 4B ,  FIG. 5B , and  FIG. 6B , respectively). 
     A manufacturing method of a circular touch panel  200   a  will be described in more detail with reference to  FIG. 7A  to  FIG. 7C . 
     The optical pattern is a pattern that changes the direction of light propagation, e.g., a pattern exhibiting at least one optical effect of a light diffraction effect, a light interference effect, and a light scattering effect. The above-mentioned optical effects help a user to observe a smoother image by smoothly alleviating a boundary of the step shape of the circular display panel  400 . 
     The optical effect generated according to an exemplary embodiment is satisfied as long as it has an effect of alleviating the boundary of the step shape of the circular display panel  400 , and is not limited by the name of the effect, such as the diffraction effect, or the like. 
     The optical pattern according to an exemplary embodiment may be configured of at least one pattern of a multiple-slit pattern, a mesh pattern, and an irregular pattern. The optical pattern is satisfied as long as it shows the optical effects described above, and the listed patterns are merely examples of available optical patterns to generate such an optical effect. 
     The optical pattern shown in  FIG. 3A  and  FIG. 3B  is a multiple-slit pattern  231 . In the multiple-slit pattern  231 , a material of the insulator  230  and an opening may be repeatedly arranged with a predetermined size. In this case, the slit pattern may have an interval of several micrometers. The circular boundary region  210  may include a non-emitting region in which pixels are not disposed. In the non-emitting region, multiple-slit pattern  231  may be disposed to change a light propagation direction so that a user may see an optical effect, such as a light diffraction effect, a light interference effect, and a light scattering effect, from the non-emitting region. Further, the multiple-slit pattern  231  may have different pattern, such as multiple recesses or indentations to produce an optical pattern, such as a light diffraction effect, a light interference effect, and a light scattering effect. 
     A repeat interval of the slit pattern may have a size changed depending on the optical effect to be shown, and the slit pattern may also be repeated at an irregular size and may also be changed while having a sequential change. 
     The insulator  230  may be configured to be transparent, but since the insulator  230  has a reflective index different from that of air, the insulator  230  may be patterned so as to have the optical effect to be implemented. 
       FIG. 4A  and  FIG. 4B  are diagrams showing shapes in which an insulator of a circular boundary region of a circular touch panel is patterned in an optical pattern of a mesh pattern according to an exemplary embodiment. 
     Unlike  FIG. 3A  and  FIG. 3B ,  FIG. 4A  and  FIG. 4B  disclose an exemplary embodiment in which the optical pattern of the circular boundary region  210  is configured of a mesh pattern  232 . 
     The mesh pattern  232  shown in  FIG. 4A  and  FIG. 4B  has diamond-shaped opening parts arranged with a predetermined interval. However, this shape is merely one exemplary embodiment. Thus, according to different configurations, a triangular, pentagonal, hexagonal, or random mesh pattern may be configured. 
       FIG. 5A  and  FIG. 5B  are diagrams showing shapes in which a first metal layer of a circular boundary region of a circular touch panel is patterned in an optical pattern of a multiple-slit pattern according to an exemplary embodiment. 
     Referring to  FIG. 5A  and  FIG. 5B , the first metal layer is patterned to configure an optical pattern instead of the insulator  230  illustrated in  FIG. 3A  and  FIG. 3B . The optical pattern illustrated in  FIG. 5A  and  FIG. 5B  is a multiple-slit pattern  233 . However, other patterns, e.g., the mesh pattern illustrated in  FIG. 4A , may be employed in configuring the first metal layer. 
     The multiple-slit pattern  231  shown in  FIG. 3A  and  FIG. 3B  is the optical pattern formed by performing the patterning together with the insulator  230  when the insulator  230  is patterned, but the multiple-slit pattern  233  shown in  FIG. 5A  and  FIG. 5B  is formed by patterning the first metal layer together with the plurality of connection wirings  260 ,  261 ,  262 , and  263  when the plurality of connection wirings  260 ,  261 ,  262 , and  263  are patterned, by depositing the first metal layer on the insulating substrate  201 . 
     Similar to the structure shown in  FIG. 3A  and  FIG. 3B , an optical effect may be obtained without adding a separate material deposition process or a separate patterning process. 
     Although the first metal layer is patterned in the multiple-slit pattern  233 , the first metal layer may also be patterned in a mesh pattern, an irregular pattern, or the like. 
     In addition, both the first metal layer and the insulator  230  may be complexly patterned, thereby configuring a complex optical pattern. In this case, since the first metal layer and the insulator  230  are materials having different reflective indexes and are patterned in different patterns from each other, more diverse optical effects may be attained. 
       FIG. 6A  and  FIG. 6B  are diagrams showing shapes in which a second metal layer of a circular boundary region of a circular touch panel is patterned in an optical pattern of a multiple-slit pattern according to an exemplary embodiment. 
     Referring to  FIG. 6A  and  FIG. 6B , the second metal layer is patterned to configure the optical pattern instead of the insulator  230  in  FIG. 3A . The optical pattern illustrated in  FIG. 6A  and  FIG. 6B  is a multiple-slit pattern  234 . However, other patterns, e.g., the mesh pattern illustrated in  FIG. 4A , may be employed in configuring the second metal layer. The second metal layer may be materially different from the metal layer formed by patterning the wirings  260 ,  261 ,  262 ,  263 , and may separately formed. 
     The multiple-slit pattern  231  shown in  FIG. 3A  and  FIG. 3B  is the optical pattern formed by performing the patterning together with the insulator  230  when the insulator  230  is patterned, but the multiple-slit pattern  234  shown in  FIG. 6A  and  FIG. 6B  is formed by patterning the second metal layer together when the plurality of first sensing electrodes  240  and  241  and the plurality of second sensing electrodes  250  and  251  are formed, by depositing and patterning the second metal layer after the plurality of connection wirings  260 ,  261 ,  262 , and  263  are patterned. 
     Similar to the structure shown in  FIG. 3A  and  FIG. 3B , an optical effect may be obtained without adding a separate material deposition process or a separate patterning process. 
     Although the second metal layer is patterned in the multiple-slit pattern  234  in  FIG. 6A  and  FIG. 6B , the second metal layer may also be patterned in a mesh pattern, an irregular pattern, or the like. 
     In addition, the second metal layer and the insulator  230  may be complexly patterned, thereby configuring a complex optical pattern. In this case, since the first metal layer and the insulator  230  are materials having different reflective indexes and are patterned in different patterns from each other, more diverse optical effects may be shown. 
     In addition, by configuring the optical pattern in which the first metal layer, the second metal layer, and the insulator  230  are complexly patterned, various optical effects may be shown. For example, the patterned first metal layer  233  of  FIG. 5A  and  FIG. 5B , the second metal layer  234  of  FIG. 6A and 6B , the pattern of the insulator  230  of  FIG. 3A  and  FIG. 3B  may be formed while the first metal layer  233  has an irregular pattern, the second metal layer  234  has a multiple-slit pattern, and the insulator  230  has a mesh pattern. 
       FIG. 7A  to  FIG. 7C  are diagrams illustrating a manufacturing method of a circular touch panel of  FIG. 3  according to an exemplary embodiment. 
     Referring to  FIG. 7A , the insulating substrate  201  is disposed and the first metal layer is deposited on the insulating substrate  201 . In this case, the first metal layer may be an opaque metal and may be configured of a single or composite material, such as silver (Ag), copper (Cu), chromium (Cr), aluminum (Al), molybdenum/aluminum/molybdenum (Mo/Al/Mo), or the like. 
     The first metal layer may be patterned using a first mask so as to form the plurality of connection wirings  260 ,  261 ,  262 , and  263 . In this case, the first metal layer may be patterned at the circular boundary region  210 , such that the optical pattern shown in  FIG. 5A  and 
       FIG. 5B  may be formed, but a repetitive description thereof will be omitted. The plurality of connection wirings  260 ,  261 ,  262 , and  263  may each have a curved portion and a connecting part connecting the curved portion and a sensing electrode, e.g., the first sensing electrode  240  as shown in  FIG. 3A . The curvature of curved portions may be determined based on the curvature of the circular boundary region  210 , which may vary depending on the radius of the circular touch panel  200  when the touch panel has a circular shape and the shape of a touch panel (e.g., an elliptical touch panel). For example, the curvature of the curved portions and the curvature of the corresponding peripheral boundary of the touch panel may be substantially the same as shown in  FIG. 7A . 
     Referring to  FIG. 7B , the second metal layer is deposited on the plurality of formed connection wirings  260 ,  261 ,  262 , and  263 . The second metal layer may include a transparent electrode such as indium tin oxide (ITO), or the like. 
     The second metal layer may be patterned, thereby forming the plurality of first sensing electrodes  240  and  241  and the plurality of second sensing electrodes  250  and  251 . In this case, the second metal layer may be patterned at the circular boundary region  210 , such that the optical pattern shown in  FIG. 6A  and  FIG. 6B  may be formed, but a repetitive description thereof will be omitted. 
     As described above, the plurality of first sensing electrodes  240  and  241  may be integrally formed in the first direction, but the plurality of second sensing electrodes  250  and  251  may be formed in the island-type, or vice versa. As described above, the shape of the sensing electrodes may be modified depending on the product configuration. 
     Referring to  FIG. 7C , after the plurality of first sensing electrodes  240  and  241  and the plurality of second sensing electrodes  250  and  251  are formed, the insulator  230  is stacked. The insulator  230  may be configured to be transparent. 
     The insulator  230  may be patterned by at least one patterning process and may be patterned to have the via-holes  270  and  271  described above with respect to the bridge electrodes  255 . In this case, the insulator  230  may be patterned together with a plurality of opening parts at the outer boundary so as to have the multiple-slit pattern  231  at the circular boundary region  210 . 
     Although not illustrated, a third metal layer is deposited and patterned, thereby forming the bridge electrode  255  connecting two adjacent electrodes of the second sensing electrodes  250  and two adjacent electrodes of the second sensing electrodes  251 . Therefore, the circular touch panel  200  shown in  FIG. 3A  and  FIG. 3B  may be configured. 
     Next, other passivation layers and an upper substrate are stacked and encapsulated, such that the circular touch panel  200  may be finished. However, the manufacturing process may be changed depending on a manufacturing product configuration. 
     In addition, in the case in which the circular touch panel  200  and the circular display panel  400  are integrally formed, the stacked structure and the connection structure may be changed. For example, outer boundary of the circular display panel  400  may have at least one of the above described optical patterns to enhance light diffraction and the like. 
     Although certain exemplary embodiments and implementations have been described herein, other embodiments and modifications will be apparent from this description. Accordingly, the inventive concept is not limited to such embodiments, but rather to the broader scope of the presented claims and various obvious modifications and equivalent arrangements.