Abstract:
A capacitive touch screen panel display, in which a touch sensor pattern may be prevented from being damaged during an ElectroStatic Discharge (ESD) test, is provided. The capacitive touch screen panel display includes a plurality of trace lines for transmitting touch signals from touch sensor patterns to a touch screen flexible printed circuit board, and a first length extension unit formed on a shortest trace line among the plurality of trace lines to extend a trace line length. Thus, touch sensor patterns may be prevented from being broken during the ESD test.

Description:
PRIORITY 
       [0001]    This application claims the benefit under 35 U.S.C. §119(a) of a Korean patent application filed on Feb. 11, 2011 in the Korean Intellectual Property Office and assigned Serial No. 10-2011-0012376, the entire disclosure of which is hereby incorporated by reference. 
       BACKGROUND OF THE INVENTION 
       [0002]    1. Field of the Invention 
         [0003]    The present invention relates to a capacitive touch screen panel display. More particularly, the present invention relates to a capacitive touch screen panel display in which a touch sensor pattern may be prevented from being damaged during an ElectroStatic Discharge (ESD) test. 
         [0004]    2. Description of the Related Art 
         [0005]    Recently, in order to reduce the weight and thickness of a mobile terminal and to widen an area of a display thereof, a touch screen panel display has been developed for use in the mobile terminal. With increased demand of the touch screen panel display, touch screen technology is applied to a resistive touch screen panel or a capacitive touch screen panel having high durability, high precision touch, and high optical characteristics. 
         [0006]      FIG. 1  is a sectional view illustrating a trace line of a touch screen panel display according to the related art. For reference, the lower side of  FIG. 1  is a rear side view of a window glass  110  of the existing capacitive touch screen panel display (not illustrated) and the upper side thereof is an enlarged view of a part adjacent to a touch screen Flexible Printed Circuit Board (FPCB)  120 . 
         [0007]    Referring to  FIG. 1 , trace lines  130 ,  131 ,  132 , and  133  are formed in a black mark area (where an image is not displayed to a user)  111  outside a display region (where an image is displayed for a user)  112 . Ends of the trace lines  130 ,  131 ,  132 , and  133  are connected to touch sensor patterns  160 ,  161 ,  162 , and  163  of the display region  112 , respectively and the other ends are connected to contacts  140 ,  141 ,  142 , and  143  of the touch screen FPCB  120 , respectively. 
         [0008]    The capacitive touch screen panel, like the existing capacitive touch screen panel display, undergoes an ElectroStatic Discharge (ESD) test to determine whether the capacitive touch screen panel display may endure a preset level of static electricity. However, since a length of a Y 1  trace line  131  (a length along a path of a trace line), as illustrated in  FIG. 1 , is the shortest length, the Y 1  trace line  131  has the lowest resistance of 12Ω. Thus, when ESD is applied to the touch screen panel display, ESD is concentrated to the Y 1  trace line via the touch screen FPCB  220  and the touch sensor patterns connected to the Y 1  trace line are broken. 
       SUMMARY OF THE INVENTION 
       [0009]    Aspects of the present invention are to address at least the above-mentioned problem and/or disadvantages and to provide at least the advantages described below. Accordingly, an aspect of the present invention is to provide a capacitive touch screen panel display in which touch sensor patterns are prevented from being damaged during an ElectroStatic Discharge (ESD) test. 
         [0010]    In accordance with an aspect of the present invention, a capacitive touch screen panel display is provided. The capacitive touch screen panel display includes a plurality of trace lines for transmitting touch signals from touch sensor patterns to a touch screen flexible printed circuit board, and a first length extension unit formed on the shortest trace line among the plurality of trace lines to extend a trace line length. 
         [0011]    In accordance with another aspect of the present invention, a capacitive touch screen panel display is provided. The capacitive touch screen panel display includes a plurality of touch sensor patterns for detecting a touch on the capacitive touch screen panel display, a plurality of trace lines respectively connected on one end to the plurality of touch sensor patterns for transmitting touch signals, and a plurality of length extension units respectively formed on the plurality of trace lines. 
         [0012]    According to the touch screen panel display, a length extension unit for extending a length of a trace line is formed on the shortest trace line so that touch sensor patterns may be prevented from being damaged during the ESD test. 
         [0013]    Moreover, resistance of the trace line on which the length extension unit is formed is equal to the resistance of an adjacent trace line so that it may prevent ESD from being concentrated on a single trace line. 
         [0014]    Other aspects, advantages, and salient features of the invention will become apparent to those skilled in the art from the following detailed description, which, taken in conjunction with the annexed drawings, discloses exemplary embodiments of the invention. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0015]    The above and other aspects, features, and advantages of certain exemplary embodiment of the present invention will be more apparent from the following description taken in conjunction with the accompanying drawings, in which: 
           [0016]      FIG. 1  is a view illustrating a trace line of a capacitive touch screen panel display according to the related art; 
           [0017]      FIG. 2  is a view illustrating a trace line of a capacitive touch screen panel display according to an exemplary embodiment of the present invention; and 
           [0018]      FIG. 3  is a schematic sectional view taken along a cutting line A-A′ of  FIG. 2  according to an exemplary embodiment of the present invention. 
       
    
    
       [0019]    Throughout the drawings, it should be noted that like reference numbers are used to depict the same or similar elements, features, and structures. 
       DETAILED DESCRIPTION OF EXEMPLARY EMBODIMENTS 
       [0020]    The following description with reference to the accompanying drawings is provided to assist in a comprehensive understanding of exemplary embodiments of the invention as defined by the claims and their equivalents. It includes various specific details to assist in that understanding but these are to be regarded as merely exemplary. Accordingly, those of ordinary skill in the art will recognize that various changes and modifications of the embodiments described herein can be made without departing from the scope and spirit of the invention. In addition, descriptions of well-known functions and constructions may be omitted for clarity and conciseness. 
         [0021]    The terms and words used in the following description and claims are not limited to the bibliographical meanings, but, are merely used by the inventor to enable a clear and consistent understanding of the invention. Accordingly, it should be apparent to those skilled in the art that the following description of exemplary embodiments of the present invention is provided for illustration purpose only and not for the purpose of limiting the invention as defined by the appended claims and their equivalents. 
         [0022]    It is to be understood that the singular forms “a,” “an,” and “the” include plural referents unless the context clearly dictates otherwise. Thus, for example, reference to “a component surface” includes reference to one or more of such surfaces. 
         [0023]      FIG. 2  is a view illustrating a trace line of a capacitive touch screen panel display according to an exemplary embodiment of the present invention.  FIG. 3  is a schematic sectional view taken along a cutting line A-A′ of  FIG. 2  according to an exemplary embodiment of the present invention. For reference,  FIG. 2  shows only Y-axis trace lines  230 ,  231 ,  232 , and  233  and X-axis trace lines are omitted for illustrative purpose. 
         [0024]    A capacitive touch screen panel display  200  according to an exemplary embodiment of the present invention will be described with reference to  FIGS. 2 and 3  as follows. 
         [0025]    Referring to  FIGS. 2 and 3 , the capacitive touch screen panel display  200  includes a display  250 , a window glass  210 , touch sensor patterns  260 ,  261 ,  262 , and  263 , and trace lines  230 ,  231 ,  232 , and  233 . 
         [0026]    The display  250  displays an image to a user and may be a Liquid Crystal Display (LCD) or an Active Matrix Organic Light Emitting Diode (AMOLED). 
         [0027]    The window glass  210  protects the display  250  from external shock, transmits the image of the display  250  toward a user, and is disposed on the display  250 . 
         [0028]    The touch sensor patterns  260 ,  261 ,  262 , and  263 , detect a touch by a user and may be made of Indium Tin Oxide (ITO). In an exemplary implementation, the touch sensor patterns  260 ,  261 ,  262 , and  263  are formed in a display area  212  on the rear side of the window glass  210 . However, the present invention is not limited thereto. For example, the touch sensor patterns  260 ,  261 ,  262 , and  263  may be formed on an upper side of an encap glass for forming AMOLED like an on-cell Touch Screen Panel (TSP) AMOLED. 
         [0029]    The trace lines  230 ,  231 ,  232 , and  233  transmit touch signals from the touch sensor patterns  260 ,  261 ,  262 , and  263  to a touch screen Flexible Printed Circuit Board (FPCB)  220 . In an exemplary implementation, the trace lines  230 ,  231 ,  232 , and  233  are formed in a black mark area  211  on the rear side of the window glass  210 . However, the present invention is not limited thereto. For example, the trace lines  230 ,  231 ,  232 , and  233  may be formed on the encap glass for forming AMOLED like the on-cell TSP AMOLED. Respective ends of the trace lines  230 ,  231 ,  232 , and  233  are connected to the touch sensor patterns  260 ,  261 ,  262 , and  263  of the display area  212  and the other ends thereof are connected to contacts  240 ,  241 ,  242 , and  243  of the touch screen FPCB  220 . 
         [0030]    In an exemplary implementation, a length extension unit  231   a  extending a trace line length is formed on the shortest Y 1  trace line  231 . In addition, length extension units  230   a  and  232   a  extending a trace line length are formed on a Y 0  trace line  230  and a Y 2  trace line  232  which are adjacent to the Y 1  trace line  231 . By doing so, respective resistances of the Y 0  trace line  230 , the Y 1  trace line  231 , and the Y 2  trace line  232  are increased. The length extension units  230   a ,  231   a , and  232   a  have a meander line shape, as illustrated in  FIG. 2 . 
         [0031]    Table 1 lists the resistance before and after length extension units of the trace lines  230 ,  231 ,  232 , and  233  are formed. For reference, the Y 3  trace line  233 , as illustrated in  FIG. 2 , does not have a length extension unit. 
         [0000]    
       
         
               
               
             
               
               
               
               
               
             
               
               
               
               
               
             
           
               
                   
                 TABLE 1 
               
             
             
               
                   
                   
               
               
                   
                 No. of trace line 
               
             
          
           
               
                   
                 Y0 
                 Y1 
                 Y2 
                 Y3 
               
               
                   
                   
               
             
          
           
               
                 Before forming 
                 237.8756 Ω 
                 12.07253 Ω 
                 226.8478 Ω 
                 452.6509 Ω 
               
               
                 extension unit 
               
               
                 After forming 
                 452.6367 Ω 
                 452.6336 Ω 
                 452.6478 Ω 
                 452.6509 Ω 
               
               
                 length 
               
               
                 extension unit 
               
               
                   
               
             
          
         
       
     
         [0032]    According to an exemplary embodiment of the present invention, resistance of the Y 1  trace line  231  is increased when the length extension unit  231   a  is formed on the shortest Y 1  trace line  231 . Thus, less current, than before the length extension unit is formed, flows through the Y 1  trace line  231  when a high voltage ESD is applied thereto. Therefore, the touch sensor pattern  261  connected to the Y 1  trace line  231  may be prevented from being broken. 
         [0033]    For reference, in an exemplary implementation, since the touch screen FPCB  220  is formed along the X-axis, the shortest trace line belongs to a Y-axis trace line. Thus, in a case when the touch screen FPCB  220  is formed in the Y-axis direction, a trace line belonging to the X-axis trace line may have a length extension line. 
         [0034]    Moreover, according to an exemplary embodiment of the present invention, resistance of the Y 1  trace line  231  (approximately 452.6Ω) is the same as the resistance of the Y 0  trace line  230  and Y 2  trace line  232  which are adjacent to the Y 1  trace line  231 . Thus, when a high voltage ESD is applied, the ESD is uniformly distributed to the Y 0  trace line  230 , the Y 1  trace line  231 , and the Y 2  trace line  232  and not concentrated to any one of the trace lines  230 ,  231 , and  232 . As a result, the touch sensor patterns are prevented from being broken. 
         [0035]    While the invention has been shown and described with reference to certain exemplary embodiments thereof, it will be understood by those skilled in the art that various changes in form and details may be made therein without departing from the spirit and scope of the invention as defined by the appended claims and their equivalents.