Abstract:
A display device with touch panel and a fabricating method thereof are provided. The display device with touch panel includes a flexible display panel and a force sensitive touch panel. The force sensitive touch panel is disposed under a portion of the flexible display panel. Since the force sensitive touch panel is only configured under the portion of the flexible display panel, the display device with touch panel may have touching control function and flexibility at the same time.

Description:
This application claims priority to a Taiwan application No. 097150504 filed Dec. 24, 2008. 
     BACKGROUND 
     1. Field of the Invention 
     The invention is related to a display device and fabricating method thereof, and more particular to a flexible display device with touch panel and fabricating method thereof. 
     2. Description of the Related Art 
     Since the back light module is replaced by the external light source for displaying in reflective display devices, the consumed energy may be reduced and the reflective display devices are suitable for being used in the portable electronic products. Thus, a touch panel is used in the display device of most portable electronic products for convenience nowadays. 
     The touch panels widely used within the display devices comprise resistive touch panels, capacitance touch panels and force sensitive touch panels. The resistive touch panel or the capacitance touch panel is disposed on the display surface of the display panel. For the reflective display device, the external light is transmitted into the display panel via the resistive touch panel or the capacitance touch panel and the light reflected by the display panel is also transmitted out of the the display panel via the resistive touch panel or the capacitance touch pane. 
     However, the transmittance of the resistive touch panel or the capacitance touch panel is only between 80% and 92%, so the brightness of the reflective display device is difficult to promote. Therefore, piezoelectric touch panel disposed under the display panel is used in most of the conventional reflective display devices to prevent the light reflected by the display panel from passing the piezoelectric touch panel, so the light energy loss may be decreased and the displaying brightness of the reflective display devices may also be increased. Nevertheless, since a rigid substrate is used as a carrier for the piezoelectric sensors of the piezoelectric touch panel, the conventional reflective display device with piezoelectric touch panel is unflexible and it is not consistent with the trend of miniaturization and the convenience of carrying of the modern display devices. 
     BRIEF SUMMARY 
     Accordingly, the invention is directed to a display device with touch panel having flexibility without sacrificing brightness. 
     The invention is directed to a method of fabricating a display device with touch panel for producing a flexible display device with touch panel without reducing the brightness thereof. 
     The invention provides a display device with touch panel comprising a flexible display panel and a force sensitive touch panel, wherein the force sensitive touch panel is disposed under a portion of the flexible display panel. 
     The invention provides a method of fabricating a display device with touch panel. First, a flexible display panel is provided. Next, a force sensitive touch panel is formed under a portion of the flexible display panel. 
     Since the force sensitive touch panel is disposed under a portion of the flexible display panel, the other portions of the flexible display panel without bonding with the force sensitive touch panel may be bent. Therefore, the display device with touch panel is flexible in the invention. 
     In order to make the aforementioned and other objects, features and advantages of the invention more comprehensible, some preferred embodiments accompanied with figures are described in detail below. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       These and other features and advantages of the various embodiments disclosed herein will be better understood with respect to the following description and drawings, in which like numbers refer to like parts throughout, and in which: 
         FIG. 1  is a schematic cross-sectional view illustrating a display device with touch panel according to an embodiment of the invention. 
         FIG. 2A  is a schematic upward view illustrating a display device with touch panel according to an embodiment of the invention. 
         FIG. 2B  is a schematic upward view illustrating a display device with touch panel according to another embodiment of the invention. 
         FIG. 2C  is a schematic upward view illustrating a display device with touch panel according to another embodiment of the invention. 
         FIG. 2D  is a schematic upward view illustrating a display device with touch panel according to another embodiment of the invention. 
         FIG. 3  is a schematic upward view illustrating a display device with touch panel according to another embodiment of the invention. 
         FIG. 4  is a schematic upward view illustrating a display device with touch panel according to another embodiment of the invention. 
         FIG. 5  is a schematic view illustrating the display device with touch panel of  FIG. 1  during a bending state. 
         FIG. 6A  to  FIG. 6D  are schematic cross-section views illustrating the display device with touch during partial fabricating process according to an embodiment of the invention. 
         FIG. 7  is a schematic cross-section view illustrating the adhesion layer is adhered with a portion of the flexible display panel according to another embodiment of the invention. 
         FIG. 8A  to  FIG. 8C  are schematic cross-section views illustrating the display device with touch panel during partial fabricating process according to an embodiment of the invention. 
     
    
    
     DETAILED DESCRIPTION 
       FIG. 1  is a schematic cross-sectional view illustrating a display device with touch panel according to an embodiment of the invention. Referring to  FIG. 1 , the display device with touch panel  10  comprises a flexible display panel  12  and a force sensitive touch panel  14  disposed under a portion of the flexible display panel  12 . 
     The flexible display panel  12  is a reflective flexible display panel, such as an electro-phoretic display panel, a cholesteric liquid crystal display panel, an organic electroluminescence display panel, a MEMS display panel or an electro-wetting display panel. The flexible display panel  12  has a upper surface  122  and a bottom surface  124  opposite to each other. The upper surface  122  is a display surface of the flexible display panel  12 . 
     The force sensitive touch panel  14  comprises a first substrate  142 , a second substrate  144  and a plurality of piezoelectric sensors  146 . The first substrate  142  is disposed above the second substrate  144  and near the bottom surface  124  of the flexible display panel  12 . The piezoelectric sensors  146  are disposed between the first substrate  142  and the second substrate  144 . In specific, the materials of the first substrate  142  and the second substrate  144  may be polycarbonate (so-called PC), polyethersulfone (so-called PES), polymethyl methacrylate (so-called PMMA), novolac plastic, glass or stainless steel. In addition, the piezoelectric sensor  146  may comprise force sensitive resistors. 
     Specially, the force sensitive touch panel  14  in this embodiment further comprises a plurality of supporting pillars  148  disposed against and between the flexible display panel  12  and the second substrate  144 . The supporting pillars  148  is used for keeping the distance between the flexible display panel  12  and the force sensitive touch panel  14  to avoid the inappropriate action of the piezoelectric sensor  146  resulted from the gravity of the flexible display panel  12  before the force sensitive touch panel  14  being pressed. 
     It should be noted that the invention is not limited to the relative horizontal positions and the ratio of the area of the force sensitive touch panel  14  and the flexible display panel  12 . As shown in  FIG. 2A  to  FIG. 2D , the area of the force sensitive touch panel  14  may be about equal or less than a half of the area of the flexible display panel  12  and corresponding any part of the flexible display panel  12 . Alternatively, the area of the force sensitive touch panel  14  may be larger than a half of the area of the flexible display panel  12 . The area of the force sensitive touch panel  14  is not limited in the invention. 
     In addition, a quadrangle force sensitive touch panel  14  is taken as the example in the embodiment, but it is not only limited to the shape of the force sensitive touch panel  14 . The shape of the force sensitive touch panel  14  may also be a circular or polygon shape, as shown in  FIG. 3  and  FIG. 4 . 
     In the display device with touch panel  10 , since the force sensitive touch panel  14  is under the flexible display panel  12 , the light is transmitted into or out of the flexible panel  12  without passing through the force sensitive touch panel  14 . Therefore, the energy loss of the light passing through the force sensitive touch panel  14  may be prevented. Thus, the displaying brightness of the display device with touch panel  10  is improved. 
     Accordingly, since the force sensitive touch panel  14  is disposed only on a portion of the flexible display panel  12 , even the force sensitive touch panel  14  consists of a rigid substrate, the other portions of the flexible display panel  12  without bonding with the force sensitive touch panel  14  is also flexible, as shown in  FIG. 5 . Therefore, the display device with touch panel  10  is consistent with the trend of the miniaturization of the portal electronic produces. 
     The fabricating method of the display device with touch panel of the invention is described in following paragraphs.  FIG. 6A  to  FIG. 6D  are schematic cross-section views illustrating the display device with touch panel during fabricating process according to an embodiment of the invention. Referring to  FIG. 6A  first, the flexible panel  12  having the upper surface  112  and the bottom surface  124  opposite to each other is provided. Then, a force sensitive touch panel  14  is formed under a portion of the flexible display panel  12 . In detail, the method of forming the force sensitive touch panel  14  under a portion of the flexible display panel  12  of this embodiment comprises forming an adhesion layer  13  on a first substrate  142 , as shown in  FIG. 6B . Next, the first substrate  142  is adhered under a portion of the flexible display panel  12  by the adhesion layer  13 , as shown in  FIG. 6C . 
     Referring  FIG. 6D , a plurality of piezoelectric sensors  146  are disposed on the second substrate  144 . The piezoelectric sensors  146  may comprise force sensitive resistors. Specifically, a plurality of supporting pillars  148  are disposed on the second substrate  144  to keep the distance between the flexible display panel  12  and the force sensitive touch panel  14  in this embodiment. Finally, the second substrate  144  with the piezoelectric sensors  146  and the first substrate  142  are assembled to each other for forming the force sensitive touch panel  14 . The supporting pillars  148  are disposed against and between the flexible display panel  12  and the second substrate  144  of the force sensitive touch panel  14 . The flexible display panel  12  and the force sensitive touch panel  14  are assembled to form the display device with touch panel  10  as shown in  FIG. 1 . 
     Referring to  FIG. 1  and  FIG. 8A  to  FIG. 8C , in another embodiment of the invention, the method of forming the force sensitive touch panel  14  comprises adhering a substrate  1420  under the flexible display panel  12  first, as shown in  FIG. 8A . Next, a portion of the substrate  1420  is removed to form the first substrate  142  under the flexible display panel  12 . In this embodiment, a portion of the substrate  1420  is removed by laser cutting method. In detail, the process of removing the portion of the substrate  1420  comprises cutting the substrate  1420  to a first partial substrate  1422  and a second partial substrate  1424  first, as shown in  FIG. 8B . Next, the first partial substrate  1422  under removing is illuminated by a laser beam and then departed from the flexible display panel  12 , as shown in  FIG. 8C . Then, the first partial substrate  1422  departed from the flexible display panel  12  is removed and the second partial substrate  1424  adhered with the flexible display panel  12  is considered the first substrate  142 . The follow-up fabricating process of the force sensitive touch panel  14  is described as the aforementioned embodiment and shown in  FIG. 6D , it is unnecessary to say herein. 
     In summary, since the force sensitive touch panel is disposed under the flexible display panel in the invention, the light is transmitted into or out of the flexible display panel without passing through the force sensitive touch panel. Therefore, the energy loss of the light passing through the force sensitive touch panel may be prevented. Thus, the displaying brightness of the display device with touch panel is improved. 
     Moreover, since the force sensitive touch panel is disposed under a portion of the flexible display panel, the other portions of the flexible display panel without bonding with the force sensitive touch panel is also flexible. Therefore, the display device with touch panel is consistent with the trend of the miniaturization of the portal electronic produces. 
     The above description is given by way of example, and not limitation. Given the above disclosure, one skilled in the art could devise variations that are within the scope and spirit of the invention disclosed herein, including configurations ways of the recessed portions and materials and/or designs of the attaching structures. Further, the various features of the embodiments disclosed herein can be used alone, or in varying combinations with each other and are not intended to be limited to the specific combination described herein. Thus, the scope of the claims is not to be limited by the illustrated embodiments.