Abstract:
A capacitive touch device structure includes a first transparent substrate, a second transparent substrate, a picture layer at the periphery of a lower surface of the first transparent substrate, first and second transparent conductive thin films formed on corresponding surfaces of the two transparent substrates respectively, a plurality of first and second circuits, and an adhesive layer for laminating the first and second transparent substrates. After the corresponding surfaces of the capacitive touch device are attached, the first or second transparent conductive thin film and the first or second circuit are considered to be in the same plane, so as to achieve the effects of reducing the thickness of the capacitive touch device, improving the light transmittance effectively, minimizing the number of layers of the first or second transparent conductive thin film and the first or second circuit, simplifying the manufacturing process and improving the yield rate.

Description:
BACKGROUND OF THE INVENTION 
       [0001]    1. Field of the Invention 
         [0002]    The present invention relates to a touch device, and more particularly to a capacitive touch device structure capable of reducing the thickness, improving the light transmittance, and simplifying the manufacturing process of a touch panel. 
         [0003]    2. Description of the Related Art 
         [0004]    Touch panel is generally divided into resistive, capacitive, ultrasonic, and optical (infrared) touch panel. Among these touch panels, the resistive touch panel is the most commonly used one, and the capacitive touch panel is the second commonly used one. Although the capacitive touch panel comes at a higher price, it has the advantages of high water resistance, scratch resistance and light transmittance as well as wide applicable temperature range. Therefore, the capacitive touch panel is introduced and used in the market of small touch panels as the technology matures. 
         [0005]    With reference to  FIG. 1  for a schematic view of a conventional touch panel structure, the conventional touch panel  1  includes at least two PET substrates  12 , two electrically conductive layers  13  disposed on a corresponding surface of the PET substrates  12  respectively, an optically clear adhesive  11  disposed between the electrically conductive layers  13  for laminating the two PET substrates  12  with each other, and the optically clear adhesive  11  disposed at another surface of any PET substrate  12  for adhering a protective layer  10 . In  FIG. 1 , the electrically conductive layer  13  has a thickness composed of at least two layers, wherein one is a metal conducting wire layer, and the other one is a conductive electrode layer, and the upper and lower electrically conductive layers  13  are formed onto at least two PET substrates  12  respectively. With the optically clear adhesive  11  and the protective layer  10 , the whole stack will become relatively thick, and thus the upper and lower electrically conductive layers  13  are formed on both corresponding surfaces of a glass substrate to reduce the thickness, or diamond sensing electrodes are manufactured on a single side of the substrate. However, it is necessary to use the optically clear adhesive  11  for the lamination as a protective layer or a decorative layer of a casing. As a result, the thickness of the touch panel still cannot be reduced effectively. Therefore, some manufacturers developed a method of reducing the thickness of a touch panel as disclosed in R.O.C. Publication No. M368846 entitled “Improved touch panel structure”, and the structure comprises a substantially transparent substrate, a color frame formed at the periphery of a surface of the substrate, and a touch sensor disposed on the substrate and having an insulation effect, such that a signal line at the edge of the touch sensor can be installed precisely under the color frame. The touch sensor uses the alignment effect of a metal bridging structure to minimize the number of layers in the overall manufacturing process. 
         [0006]    The touch sensor has a capacitive sensing layer, a barrier layer and a jumper electrical conducting layer The capacitive sensing layer includes a plurality of sensing units arranged along equidistant X-axis and Y-axis tracks on a substrate, wherein the sensing units arranged in an axis track are connected to each other, and the sensing units arranged in the other axis track are not connected to each other, and finally an insulating layer and the jumper electrical conducting layer are laid to electrically connect track sensing units arranged along each axis tracks. To achieve a uniform light transmittance, the aforementioned patent further comprises a substance disposed between X-axis and Y-axis sensing units and having decorative lines and made of the same material of the two axis sensing units, wherein an interval must be maintained between the decorative lines and the edge of each sensing unit, such that the decorative lines and the sensing units are not connected. Although this patented technology can reduce the number of layers and the thickness, the manufacture of the sensing electrode becomes very complicated. 
         [0007]    Further, a “capacitive touch panel” as disclosed in R.O.C. Pat. Publication No. M355426 comprises a hard substrate and a patterned conductive film, wherein an upper surface of the hard substrate is a touch end of the touch panel, and a lower surface of the hard substrate includes at least one mask pattern, a viewable area and a plurality of conductor circuits, wherein the viewable area is enclosed by at least one mask pattern, and the conductor circuits are formed on the mask pattern and jointly extended to a side of an external periphery of the mask pattern. The patterned conductive film includes a plurality of electrode circuits corresponding to the range of the viewable area and connected to the conductor circuits respectively. The lower surface of the hard substrate is provided for laying wires for the touch panel structure, and the patterned electrically conductive layer is the same as disclosed in the aforementioned patent. In other words, the X-axis and Y-axis sensing electrodes are manufactured on a single surface of the substrate, and then an insulating layer is formed onto the sensing electrode, such that the insulating layer has a hollow portion disposed at a position opposite to at least one end of each sensing electrode, and finally a transparent conductive thin film is coated onto the insulating layer, and with the bridge conductive wire formed after the patternization process. Although the structure reduces the usage of substrates, the manufacturing process requires the steps of coating a plurality of films onto a single substrate as well as the etching process. 
       SUMMARY OF THE INVENTION 
       [0008]    In view of the shortcomings of the prior art, the inventor of the present invention based on years of experience in the related industry to conduct extensive researches and experiments, and finally developed a capacitive touch device structure in accordance with the present invention to overcome the shortcomings of the prior art. 
         [0009]    Therefore, it is a primary objective of the present invention to overcome the aforementioned shortcoming and deficiency of the prior art by providing a capacitive touch device structure that can lower the overall thickness of a touch panel. 
         [0010]    Another objective of the present invention is to provide a capacitive touch device structure that can simplify the manufacturing process for a touch panel. 
         [0011]    Another objective of the present invention is to provide a capacitive touch device structure that can improve the light transmittance. 
         [0012]    To achieve the foregoing objectives, the present invention provides a capacitive touch device structure comprising a first transparent substrate, a picture layer, a first transparent conductive thin film, a second transparent substrate, a second transparent conductive thin film, and an adhesive layer. 
         [0013]    The first transparent conductive thin film is coated onto a lower surface of the first transparent substrate, wherein the first transparent conductive thin film includes a plurality of first sensing electrodes and a plurality of first circuits, and the first sensing electrodes are respectively and electrically coupled to the first circuits, and the picture layer is disposed between the periphery of a lower surface of the first transparent substrate and the first transparent conductive thin film, and the picture layer is a planar hollow frame structure, and the first circuits have a wiring area covered by an area range of the picture layer. 
         [0014]    The second transparent conductive thin film is coated onto an upper surface of the second transparent substrate, wherein the second transparent conductive thin film includes a plurality of second sensing electrodes and a plurality of second circuits, and the second sensing electrodes are electrically coupled to the second circuits respectively, and the second circuits are disposed opposite to a cladding area of the picture layer on the first transparent substrate, and whose wiring area is covered by an area range of the picture layer, and the first sensing electrodes and the second sensing electrodes are intersected perpendicularly with each other. 
         [0015]    After the first transparent substrate and the second transparent substrate are attached by an adhesive layer, the picture layer is covered at the periphery of the lower surface of the first transparent substrate, whose interior hollow area is the covering area of the first transparent conductive thin film, and the first circuits are installed within the range area of the picture layer, and the intersection of the picture layer and the first transparent conductive thin film is near the electric connecting positions of the first sensing electrodes and the first circuits, so that the first transparent conductive thin film and the first circuits are considered to be in the same plane, and the thickness can be reduced effectively. In addition, the second transparent conductive thin film, the second circuits and the second sensing electrodes of the second transparent substrate are installed in the same way as those of the first transparent substrate, such that the overall thickness of the capacitive touch device can be reduced. In the meantime, the present invention can simplify the manufacturing process of the prior art that requires a complicated sequential processes. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0016]      FIG. 1  is a schematic view of a conventional touch panel; 
           [0017]      FIG. 2  is an exploded view of a touch panel in accordance with a preferred embodiment of the present invention; 
           [0018]      FIG. 3  is a cross-sectional view of an assembled touch panel in accordance with a preferred embodiment of the present invention; 
           [0019]      FIG. 4A  is a first schematic view of a circuit in accordance with a preferred embodiment of the present invention; 
           [0020]      FIG. 4B  is a second schematic view of a circuit in accordance with a preferred embodiment of the present invention; 
           [0021]      FIG. 5  is an exploded view of a touch panel in accordance with another preferred embodiment of the present invention; 
           [0022]      FIG. 6  is a cross-sectional view of an assembled touch panel in accordance with another preferred embodiment of the present invention. 
       
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
       [0023]    The technical characteristics of the present invention will become apparent with the detailed description of the preferred embodiments and the illustration of the related drawings. 
         [0024]    With reference to  FIGS. 2 and 3  for an exploded view and a cross-sectional view of a capacitive touch device structure in accordance with a preferred embodiment of the present invention, the capacitive touch device structure includes a capacitive touch device  2  comprising a first transparent substrate  21 , a first transparent conductive thin film  211 , a second transparent substrate  22 , a second transparent conductive thin film  221 , a picture layer  23  and an adhesive layer  24  for laminating the transparent substrates  21 ,  22 . 
         [0025]    The first transparent substrate  21  is composed of a group of transparent plate made of a material selected from glass, polyethylene terephthalate (PET), polycarbonate (PC), polyethylene (PE), polyvinyl Chloride (PVC), polypropylene (PP), polystyrene (PS), polymethylmethacrylate (PMMA), or cycloolefin copolymer (COC). 
         [0026]    The picture layer  23  is a planar hollow frame structure composed of ink, and disposed at the periphery of a lower surface of the first transparent substrate  21 . 
         [0027]    The first transparent conductive thin film  211  is coated onto a lower surface of the first transparent substrate  21  and disposed on an internal side of a range enclosed by the picture layer  23 , and made of an impurity-doped oxide selected from the collection of indium tin oxide (ITO), indium zinc oxide (IZO), Al-doped ZnO (AZO) and antimony tin oxide (ATO). 
         [0028]    With reference to  FIG. 4A , the first transparent conductive thin film  211  includes a plurality of first sensing electrodes  212  disposed in a horizontal direction (or X-axis direction) or a vertical direction (or Y-axis direction) on the first transparent conductive thin film  211 . 
         [0029]    A plurality of first circuits  213  are made of a metal such as chromium, aluminum, silver, molybdenum, copper and gold or any one of their alloys, and the plurality of first circuits  213  are electrically coupled to the first sensing electrodes  212  respectively, and the first circuits  213  have a wiring area covered within an area range of the picture layer  23 . 
         [0030]    The second transparent substrate  22  is made of a transparent sheet material group selected from glass, polyethylene terephthalate (PET), polycarbonate (PC), polyethylene (PE), polyvinyl Chloride (PVC), polypropylene (PP), polystyrene (PS), polymethylmethacrylate (PMMA), cycloolefin copolymer (COC). 
         [0031]    The second transparent conductive thin film  221  is coated onto an upper surface of the second transparent substrate  22  and made of an impurity-doped oxide selected from indium tin oxide (ITO), indium zinc oxide (IZO), Al-doped ZnO (AZO) or antimony tin oxide (ATO). 
         [0032]    With reference to  FIG. 4B , the second transparent conductive thin film  221  is coated in a horizontal direction (or X-axis direction) or a vertical direction (or Y-axis direction) and includes a plurality of second sensing electrodes  222  disposed on the second transparent conductive thin film  221 , and a plurality of second circuits  223  made of a metal such as chromium, aluminum, silver, molybdenum, copper and gold or any one of their alloys, and the plurality of second circuits  223  are electrically coupled to the second sensing electrodes  222  respectively. 
         [0033]    The adhesive layer  24  is mainly composed of an optically clear adhesive (OCA), and disposed between the first circuit  213  of the first transparent substrate  21  and the second circuit  223  of the second transparent substrate  22 , for laminating the lower surface of the first transparent substrate  21  with the upper surface of the second transparent substrate  22 . It is noteworthy to point out that after the first transparent substrate  21  and the second transparent substrate  22  are laminated, the second circuits  223  are arranged opposite to a cladding area of the picture layer  23  on the first transparent substrate  21 , and whose wiring area is covered within the area range of the picture layer  23 . In the meantime, the first sensing electrodes  212  and the second sensing electrodes  222  are intersected perpendicularly with each other. In other words, if the first sensing electrodes  212  are arranged in the horizontal direction (X-axis direction), then the second sensing electrodes  222  will be arranged in the vertical direction (Y-axis direction). On the other hand, if the first sensing electrodes  212  are arranged in the vertical direction (Y-axis direction), then the second sensing electrodes  222  will be arranged in the horizontal direction (X-axis direction). 
         [0034]    With the aforementioned method, after the adhesive layer  24  is used for laminating the first transparent substrate  21  and the second transparent substrate  22  with each other, the interior of the picture layer  23  is a hollow area which is a covering area of the first transparent conductive thin film  211 , and the first circuits  213  are installed within the area range of the picture layer  23 , so that the intersection of the picture layer  23  and the first transparent conductive thin film  211  is near the electric connecting positions of the first sensing electrodes  212  and the first circuits  213 , and the first transparent conductive thin film  211 , the first sensing electrodes  212  and the first circuits  213  can be considered to be in the same plane, and the picture layer  23 , the first sensing electrode  212  and the first circuit  213  are formed in the same substrate (which is the first transparent substrate  21  in this embodiment), and thus the thickness can be reduced effectively. In addition, the second transparent conductive thin film  221 , the second sensing electrodes  212  and the second circuits  223  of the second transparent substrate  22  are installed in the same way as those of the first transparent substrate  21 , so that the overall thickness of the capacitive touch device  2  can be reduced, and the light transmittance of the capacitive touch device  2  can be improved. In the meantime, the present invention can simplify the manufacturing process of the prior art that requires complicated sequential processes, and can reduce the laminating process to improve the yield rate. 
         [0035]    With reference to  FIGS. 5 and 6  for an exploded view and a cross-sectional view of a capacitive touch panel in accordance with another preferred embodiment of the present invention respectively, the capacitive touch device structure includes a capacitive touch device  3 , comprising a third transparent substrate  31 , a third transparent conductive thin film  311 , a fourth transparent substrate  32 , a fourth transparent conductive thin film  321 , a picture layer  33 , an adhesive layer  34  for laminating the transparent substrates and a protective layer  35 . 
         [0036]    The third transparent substrate  31  is made of transparent sheet material group such as glass, polyethylene terephthalate (PET), polycarbonate (PC), polyethylene (PE), polyvinyl Chloride (PVC), polypropylene (PP), polystyrene (PS), polymethylmethacrylate (PMMA) or cycloolefin copolymer (COC). 
         [0037]    The picture layer  33  is a planar hollow frame structure composed of ink and disposed at the periphery of a lower surface of the third transparent substrate  31 . 
         [0038]    The third transparent conductive thin film  311  is passed through the picture layer  33  disposed on a lower surface of the third transparent substrate  31 , and made of an impurity-doped oxide such as indium tin oxide (ITO), indium zinc oxide (IZO), Al-doped ZnO (AZO) or antimony tin oxide (ATO). 
         [0039]    The third transparent conductive thin film  311  includes a plurality of third sensing electrodes  312  coated in a horizontal direction (or X-axis direction) or a vertical direction (or Y-axis direction), and the third transparent conductive thin film  311  are coated onto a lower surface of the third transparent substrate  31 . 
         [0040]    The plurality of third circuits  313  are installed on the picture layer  33  and electrically coupled to the third sensing electrodes  312  respectively, and the third circuits  313  has a wiring area covered within the area range of the picture layer  33 , and is made of a metal such as chromium, aluminum, silver, molybdenum, copper and gold or any one of their alloys. 
         [0041]    The fourth transparent substrate  32  is made of a transparent sheet material group selected from glass, polyethylene terephthalate (PET), polycarbonate (PC), polyethylene (PE), polyvinyl Chloride (PVC), polypropylene (PP), polystyrene (PS), polymethylmethacrylate (PMMA), or cycloolefin copolymer (COC). 
         [0042]    The fourth transparent conductive thin film  321  is coated onto a lower surface of the fourth transparent substrate  32  and made of an impurity-doped oxide such as indium tin oxide (ITO), indium zinc oxide (IZO), Al-doped ZnO (AZO) or antimony tin oxide (ATO). 
         [0043]    The fourth transparent conductive thin film  321  includes a plurality of fourth sensing electrodes  322 , and the fourth transparent conductive thin film  321  is coated onto a lower surface of the fourth transparent substrate  32 , and the plurality of the fourth circuit  323  are disposed at the periphery of the lower surface of the fourth transparent substrate  32 , and electrically coupled to the fourth sensing electrodes  322  respectively, and made of a metal such as chromium, aluminum, silver, molybdenum, copper and gold or any one of their alloys. 
         [0044]    To protect the fourth circuit  323  from being damaged during transportations or at a later-stage manufacturing process, a protective layer  35  is coated onto the fourth circuit, and the protective layer  35  is a single-sided optically clear adhesive (OCA). 
         [0045]    The adhesive layer  34  mainly composed of an optically clear adhesive (OCA) is disposed between the third circuit  313  of the third transparent substrate  31  and the upper surface of the fourth transparent substrate  32  for laminating a lower surface of the third transparent substrate  31  with an upper surface of the fourth transparent substrate  32 . It is noteworthy to point out that after the third transparent substrate  31  and the fourth transparent substrate  32  are laminated with each other, the fourth circuits  323  are disposed opposite to a cladding area of the picture layer  33  on the third transparent substrate  31 , and whose wiring area is covered within an area range of the picture layer  33 . In the meantime, the third sensing electrodes  312  and the fourth sensing electrodes  322  are intersected perpendicularly with each other. In other words, if the third sensing electrodes  312  are arranged in a horizontal direction (X-axis direction), then the fourth sensing electrodes  322  will be arranged in a vertical direction (Y-axis direction). On the other hand, if the third sensing electrodes  312  are arranged in the vertical direction (Y-axis direction), then the fourth sensing electrodes  322  will be arranged in the horizontal direction (X-axis direction). 
         [0046]    In summation of the description above, the present invention improves over the prior art and complies with patent application requirements, and thus is duly filed for the patent application. 
         [0047]    While the invention has been described by device of specific embodiments, numerous modifications and variations could be made thereto by those generally skilled in the art without departing from the scope and spirit of the invention set forth in the claims.