Abstract:
A touch panel has a pattern layer which designates positions of sensing areas respectively activating specific functions after being pressed, and is mounted on a top surface or a bottom surface of a lower substrate. As the substrates and sensing units mounted on the substrates are all transparent, the pattern layer can be visible when seen from the top surface of the touch panel. When the position of the pattern layer is pressed by a finger, the sensitivity upon pressing the pattern layer can be enhanced, since the pattern layer does not get in the way between the finger and the sensing unit.

Description:
BACKGROUND OF THE INVENTION 
       [0001]    1. Field of the Invention 
         [0002]    The present invention relates to a touch panel, and more particularly to a touch panel having a pattern layer, which designates positions of sensing areas respectively activating specific functions after being pressed and is mounted on a top surface or a bottom surface of a lower substrate, so as to remove obstruction between the sensing areas and a pressing object and enhance sensitivity of touch control. 
         [0003]    2. Description of the Related Art 
         [0004]    Touch panels can be classified into many types based on various technical theories. Among them, the ones using conducting film to sense voltage or capacitance variation prevail. With reference to  FIG. 9 , a conventional single-substrate surface capacitive touch panel has a substrate  60  and a top layer  70 . The substrate  60  has a conductive layer  61  mounted under the top layer  70  and is made from indium tin oxide (ITO). When a point on a touch area of the top layer  70  is touched by a finger, capacitive variation occurs at a place of the conductive layer  61  corresponding to the touched point. A signal of the variation is outputted to a controller through wires (not shown) connected with the conductive layer  61  for calculation of coordinates of the touched point. 
         [0005]    With reference to  FIG. 10 , an ink layer  71  and a pattern layer  72  are printed on the bottom of the top layer  70 . An area not occupied by the ink layer  71  and the pattern layer  72  is a touch zone. The ink layer  71  serves to mask nontransparent wires, and the pattern layer  72  serves to indicate specific positions on the conducting layer  61 . When each specific position is touched, the controller computes to acquire the specific position and outputs a corresponding command to other elements to perform specific function. 
         [0006]    However, the pattern layers  72  in touch panels fabricated with current technologies are mounted on a top side of the conducting layer  61 , meaning that when touching such type of touch panels, a finger must contact the conducting layer  61  through the pattern layer  72 . As a result, the capacitive variation generated when the finger touches a position of the top layer  70  corresponding to the pattern layer  72  is less than that generated when the finger touches a position of the top layer  70  corresponding to a touch zone, and the touch corresponding to the pattern layer  72  is less sensitive. 
         [0007]    Moreover, the pattern layer  72  and the ink layer  71  are usually printed with different colors and the pattern layer  72  contains patterns dedicated to denote positions from which specific functions can be respectively activated. Due to customization demand, the pattern layer  72  is usually printed after the printing of the ink layer  71 , and the printing of the ink layer  71  and the pattern layer  72  takes multiple printing processes to be completed. In case of any printing error, the whole top layer  70  is defective and must be discarded. As a consequence, the production cost of the conventional touch panel is inevitably escalated. 
       SUMMARY OF THE INVENTION 
       [0008]    An objective of the present invention is to provide a touch panel having a pattern layer which designates positions of sensing areas respectively activating specific functions after being pressed and is mounted on a top surface or a bottom surface of a lower substrate to remove obstruction between the sensing areas and a pressing object and enhance sensitivity of touch control. 
         [0009]    To achieve the foregoing objective, when a single-substrate touch panel is provided, the touch panel has a substrate, at least one pattern layer and a sensing unit. 
         [0010]    The substrate is transparent and has a top surface and a bottom surface. The at least one pattern layer is mounted on at least one side portion of a surface of the substrate. The sensing unit is transparent and is mounted on the surface of the substrate and overlapped on the pattern layer. 
         [0011]    To achieve the foregoing objective, when a double-substrate touch panel is provided, the touch panel has a lower substrate, a separation layer and an upper substrate. 
         [0012]    The lower substrate is transparent and has a top surface, a bottom surface and at least one pattern layer and a lower sensing unit. The at least one pattern layer is formed on at least one side portion of a surface of the lower substrate. The lower sensing unit is transparent and is mounted on the surface of the lower substrate. 
         [0013]    The separation layer is formed on the surface of the lower substrate and has a top surface. 
         [0014]    The upper substrate is transparent, is formed on the top surface of the separation layer, and has a bottom surface and an upper sensing unit. The upper sensing unit is transparent and is formed on the bottom surface of the upper substrate. 
         [0015]    At least one of the upper sensing unit and the lower sensing unit is covered on the pattern layer. 
         [0016]    Because the pattern layer can be mounted on the top surface or the bottom surface of the substrate under the sensing unit and the substrate and sensing unit are all made of transparent materials, the pattern layer is visible when seen from the top surface of the touch panel. Besides, the pattern layer does not get in the way between a finger and the sensing unit when the finger touches a touch area of the touch panel corresponding to the pattern layer. Accordingly, the sensitivity upon touching is enhanced. Since the pattern layer and the ink layer are separately located on different layers of the substrate, it is unnecessary for the ink layer to be mounted again for mistakes committed such as location deviation and incorrect color upon mounting the pattern layer, and the resulting production cost loss can be relatively mitigated. 
         [0017]    Other objectives, advantages and novel features of the invention will become more apparent from the following detailed description when taken in conjunction with the accompanying drawings. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0018]      FIG. 1  is an exploded perspective view of a single-substrate surface capacitive touch panel in accordance with the present invention; 
           [0019]      FIG. 2  is a side view in partial section of the surface capacitive touch panel in  FIG. 1  with the pattern layer mounted on a bottom surface of a substrate; 
           [0020]      FIG. 3  is another side view in partial section of the surface capacitive touch panel in  FIG. 1  with the pattern layer mounted on a top surface of a substrate; 
           [0021]      FIG. 4  is an exploded perspective view of a single-substrate projected capacitive touch panel in accordance with the present invention; 
           [0022]      FIG. 5  is an exploded perspective view of a double-substrate surface capacitive touch panel in accordance with the present invention; 
           [0023]      FIG. 6  is an exploded perspective view of a double-substrate projected capacitive touch panel in accordance with the present invention; 
           [0024]      FIG. 7  is an exploded perspective view of a double-substrate matrix capacitive touch panel in accordance with the present invention; 
           [0025]      FIG. 8  is an exploded perspective view of a double-substrate resistive touch panel in accordance with the present utility model; 
           [0026]      FIG. 9  is an side view in partial section of a conventional surface capacitive touch panel; and 
           [0027]      FIG. 10  is a top view of the surface capacitive touch panel in  FIG. 9 . 
       
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
       [0028]    The present invention is characterized by a pattern layer mounted on at least one of a top surface and a bottom surface of a substrate. Such characteristic can be applied to touch panels developed by different technologies, such as single-substrate capacitive touch panels and single-substrate projected capacitive touch panels, double-substrate projected capacitive touch panels, double-substrate matrix capacitive touch panels and double-substrate resistive touch panels described in the following embodiments. 
         [0029]    With reference to  FIG. 1 , a single-substrate surface capacitive touch panel in accordance with the present invention has a substrate  10  and a top panel  20 . The substrate  10  is transparent and has at least one pattern layer  11 , a sensing unit (A) and four wires  12 . With reference to  FIG. 2 , a pattern layer  11  is mounted on a side portion of a bottom surface of the substrate  10 . With reference to  FIG. 3 , the pattern layer  11  is mounted on a side portion of a top surface of the substrate  10 . The sensing unit (A) is transparent and is mounted on the top surface of the substrate  10  and is overlapped on the pattern layer  11 . In  FIGS. 2 and 3 , the sensing unit (A) is a rectangular conducting layer  13  and is made from ITO. One end of each wire  12  is connected to one of the corners of the conducting layer  13 , and the other end extends toward one of the corners of the substrate  10 . 
         [0030]    The top panel  20  is mounted on the sensing unit (A) and has an ink layer  21 . The ink layer  21  is nontransparent, is mounted on either one of a top surface or a bottom surface of the top panel  20 , and is correspondingly covered on the wires  12 . In the present embodiment, the ink layer is frame-shaped and is mounted on the bottom surface of the top panel  20 . Besides, one portion of the ink layer  21  corresponding to each one of the at least one pattern layer  11  is hollowed out. 
         [0031]    With reference to  FIG. 4 , a single-substrate projected capacitive touch panel in accordance with the present invention is shown. A substrate  10 ′, a pattern layer  11 ′, a top panel  20 ′ and a ink layer  21 ′ provided by the present embodiment is common to those of the foregoing surface capacitive touch panel, except that the sensing unit (A) differs from that in the foregoing surface capacitive touch panel. In the present embodiment, the sensing unit (A) has a plurality of first conducting layers  14  and a plurality of second conducting layers  15  that crossly align with each other. The first conducting layers  14  parallelly align in a first direction. Each first conducting layer  14  has a plurality of first sensing areas  141  and a first port  142 . The first sensing areas  141  are serially connected and formed by ITO. The first port  142  of each first conducting layer  14  is formed on an edge of an outermost first sensing area  141  of the first conducting layer  14  in the first direction, and is formed by a conductive material. The second conducting layers  15  are formed on an unfilled space defined by the first conducting layers  14  and parallelly align in a second direction that is perpendicular to the first direction. Each second conducting layer  15  has a plurality of second sensing areas  151  and a second port  152 . The second sensing areas  151  are serially connected and formed by ITO. The second port  152  of each second conducting layer  15  is formed on an edge of an outermost second sensing area  151  of the second conducting layer  15  in the second direction, and is formed by a conductive material. The substrate  10 ′ further has a plurality of wires  12 ′. The wires  12 ′ are formed on the top surface of the substrate  10 ′. A count of the wires  12 ′ corresponds to that of the first ports  142  and the second ports  152  on the first conducting layer  14  and the second conducting layer  15 . One end of each wire  12 ′ is connected to one of the first ports  142  and the second ports  152 . 
         [0032]    With reference to  FIG. 5 , a double-substrate touch panel, regardless of a resistive touch panel, a projected capacitive touch panel or a matrix capacitive touch panel, has a lower substrate  30 , a separation layer  40  and an upper substrate  50 . 
         [0033]    The lower substrate  30  is transparent and has at least one pattern layer  31  and a lower sensing unit (A 1 ). The at least one pattern layer  31  is formed on a side portion of a top surface or a bottom surface of the lower substrate  30 . In  FIG. 5 , the pattern layer  31  is mounted on the bottom surface of the lower substrate  30 . The lower sensing unit (A 1 ) is transparent and is mounted on the top surface of the lower substrate  30 . The separation layer  40  is formed on the top surface of the lower substrate  30 . The upper substrate  50  is transparent, is formed on a top surface of the separation layer  40 , and has an upper sensing unit (A 2 ) and an ink layer  51 . The upper sensing unit (A 2 ) or the lower sensing unit (A 1 ) is transparent, is formed on the bottom surface of the upper substrate  50 , and is covered on the pattern layer  31 . The ink layer  51  is mounted on a top surface of the upper substrate  50  or between the upper substrate  50  and the upper sensing unit (A 2 ). In  FIG. 5 , the ink layer  51  is mounted on the top surface of the upper substrate  50  and corresponds to a portion of the lower substrate  30  having no pattern layer  31 . 
         [0034]    The difference of resistive touch panels, projected capacitive touch panels and matrix capacitive touch panels lies in the upper sensing unit (A 2 ), the lower sensing unit (A 1 ) and the separation layer  40 . 
         [0035]    With reference to  FIG. 6 , a double-substrate projected capacitive touch panel in accordance with the present invention is shown. 
         [0036]    The lower sensing unit (A 1 ) has a plurality of lower conducting layers  32  parallelly aligning in a first direction. Each lower conducting layer  32  has a plurality of sensing areas  321  and a lower port  322 . The sensing areas  321  are serially connected and formed by ITO. The lower port  322  of each lower conducting layer  32  is formed on an edge of an outermost sensing area  321  of the lower conducting layer  32  in the first direction, and is formed by a conductive material. The upper sensing unit (A 1 ) is formed on an unfilled space defined by the lower conducting layers  32  on the top surface of the lower substrate  30 , and has a plurality of upper conducting layers  52  parallelly aligning in a second direction that is perpendicular to the first direction. Each upper conducting layer  52  has a plurality of sensing areas  521  and an upper port  522 . The sensing areas  521  are serially connected and formed by ITO. The upper port  552  of each upper conducting layer  52  is formed on an edge of an outermost sensing area  521  of the upper conducting layer  52  in the second direction, and is formed by a conductive material. 
         [0037]    The lower substrate  30  further has a plurality of lower wires  33 . The lower wires  33  are formed on the top surface of the lower substrate  30 . A count of the lower wires  33  corresponds to that of the lower ports  322  on the lower conducting layer  32 . One end of each wire  33  is connected to one of the lower ports  322 . 
         [0038]    The upper substrate  50  further has a plurality of lower wires  53 . The upper wires  53  are formed on the bottom surface of the upper substrate  50 . A count of the upper wires  53  corresponds to that of the upper ports  522  on the upper conducting layer  52 . One end of each upper wire  53  is connected to one of the upper ports  522 . 
         [0039]    With reference to  FIG. 7 , a double-substrate matrix capacitive touch panel in accordance with the present invention is shown. 
         [0040]    The lower sensing unit (A 1 ) has a plurality of juxtaposed lower conducting layers  32 ′. The lower conducting layers  32 ′ are rectangular, align in a first direction, and are formed by ITO. Each lower conducting layer  32 ′ has a lower port  322 ′. The lower port  322 ′ is formed on one side of the corresponding lower conducting layer  32 ′ that is perpendicular to the first direction and is made from a conductive material. The separation layer  40  is mounted between the upper substrate  50  and the lower substrate  30 , is transparent and is made of an insulating adhesive. 
         [0041]    The upper sensing unit (A 2 ) has a plurality of juxtaposed upper conducting layers  52 ′. The upper conducting layers  52 ′ are rectangular, align in a second direction that is perpendicular to the first direction, are formed by ITO, and are intersected with the lower conducting layers  32 ′ in the form of columns and rows of a matrix. Each upper conducting layer  52 ′ has an upper port  522 ′. The upper port  522 ′ is formed on one side of the corresponding upper conducting layer  52 ′ that is perpendicular to the second direction and is made of a conductive material. 
         [0042]    The lower substrate  30  further has a plurality of lower wires  33 ′. The lower wires  33 ′ are formed on the top surface of the lower substrate  30 . A count of the lower wires  33 ′ corresponds to that of the lower ports  322 ′. One end of each lower wire  33 ′ is connected to one of the lower ports  322 ′. 
         [0043]    The upper substrate  50  further has a plurality of lower wires  53 ′. The upper wires  53 ′ are formed on the bottom surface of the upper substrate  50 . A count of the upper wires  53 ′ corresponds to that of the upper ports  522 ′. One end of each upper wire  53 ′ is connected to one of the upper ports  522 ′. 
         [0044]    With reference to  FIG. 8 , a double-substrate resistive touch panel in accordance with the present invention is shown. 
         [0045]    The lower sensing unit (A 1 ) has a lower conducting layer  32 ″ made from ITO. The lower conducting layer  32 ″ has at least one lower wire  33 ″ mounted on the lower conducting layer  32 ″. In  FIG. 8 , the double-substrate resistive touch panel is a 5-wire resistive touch panel, and four lower wires  33 ″ are mounted on the top surface of the lower conducting layer  32 ″. 
         [0046]    The upper sensing unit (A 2 ) has an upper conducting layer  52 ″ made from ITO. The upper conducting layer  52 ″ has at least one upper wire  53 ″ mounted on the upper conducting layer  52 ″. In  FIG. 8 , one upper wire  53 ″ is mounted on the bottom surface of the upper conducting layer  52 ″. 
         [0047]    The separation layer has an insulating layer  41 ″ and a spacer layer  42 . The insulating layer  41 ″ is frame-shaped, and is covered on the lower wires  33 ″ and the upper wire  53 ″ but not on the pattern layer  31 . The spacer layer  42  is mounted within the insulating layer  41 ″. 
         [0048]    From the foregoing embodiments, the pattern layer  31  is mounted on a side portion of the top surface or the bottom surface of the substrate  10  or the lower substrate  30 . As the substrate  10 , the lower substrate  30 , the upper substrate  50 , the sensing unit (A), the lower sensing unit (A 1 ) and the upper sensing unit (A 2 ) are made of transparent materials, the pattern layer  31  can be visible when seen from the top surface of the touch panel. When the touch panel is pressed by a finger, the pattern layer is not present between the finger and the sensing unit (A) or the upper sensing unit (A 1 ). Accordingly, the sensitivity issue of the presence of the pattern layer in the conventional touch panels is overcome. Moreover, because the pattern layer  31  and the ink layer  51  are respectively mounted on different layers of the substrate, it is unnecessary for the ink layer  51  to be replaced even if the pattern layer  31  is off the intended position or is printed with the wrong color, and the resulting cost loss can be reduced. 
         [0049]    Even though numerous characteristics and advantages of the present invention have been set forth in the foregoing description, together with details of the structure and function of the invention, the disclosure is illustrative only. Changes may be made in detail, especially in matters of shape, size, and arrangement of parts within the principles of the invention to the full extent indicated by the broad general meaning of the terms in which the appended claims are expressed.