Abstract:
A display device such as a liquid crystal display (LCD) includes a display panel having a display surface and a back surface parallel to the display surface, a backlight module provided below the display panel, and a masking film having an electrically conductive characteristic. The masking film is attached to a peripheral region of the back surface of the display panel, and includes a connecting portion directly contacting the grounding member, such as a grounding pad of a flexible printed circuit (FPC) board and a metal frame. The display device is capable of discharging static electricity.

Description:
BACKGROUND 
       [0001]    1. Technical Field 
         [0002]    The present disclosure related to display devices, and more particularly to a liquid crystal display (LCD) which is configured to safely discharge static electricity from a display surface side of an LCD panel thereof. 
         [0003]    2. Description of Related Art 
         [0004]    Since LCDs have the advantages of portability, low power consumption, and low radiation, they have been widely used in various portable electronic products, such as notebook computers and personal digital assistants (PDAs). LCDs are also steadily replacing cathode ray tube (CRT) monitors commonly used with personal computers. 
         [0005]    In general, an LCD is configured such that a backlight module, a display control circuit board, and the like are attached to an LCD panel, and then all these parts are accommodated in a frame. Friction between the LCD panel and the outside environment can generate much static electricity, which collects on surfaces of the LCD panel, particularly on peripheral regions of the surfaces. When the amount of collected static electricity is large, electrostatic discharge (ESD) may occur, and certain ESDs are liable to damage microcircuits inside the LCD panel. The result can seriously affect the performance and display quality of the LCD. 
         [0006]    What is needed, therefore, is a display device, more particularly an LCD, that can overcome the above-described deficiencies. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0007]    The components in the drawings are not necessarily drawn to scale, the emphasis instead being placed upon clearly illustrating the principles of at least one embodiment. In the drawings, like reference numerals designate corresponding parts throughout the various views. 
           [0008]      FIG. 1  is an exploded, isometric view of a first embodiment of a display device of the present disclosure. 
           [0009]      FIG. 2  is an assembled view of the display device of  FIG. 1 . 
           [0010]      FIG. 3  is an enlarged, abbreviated cross-section of the display device, taken along line III-III of  FIG. 2 . 
           [0011]      FIG. 4  is an exploded, isometric view of a second embodiment of a display device of the present disclosure. 
           [0012]      FIG. 5  is an enlarged, abbreviated cross-section of the display device of  FIG. 4  after assembly. 
           [0013]      FIG. 6  is an exploded, isometric view of a third embodiment of a display device of the present disclosure. 
       
    
    
     DETAILED DESCRIPTION 
       [0014]    Reference will now be made to the drawings to describe certain exemplary embodiments of the present disclosure in detail. 
         [0015]    Referring to  FIG. 1 , a first embodiment of a display device of the present disclosure is shown. The display device may be an LCD, a light-emitting diode device, or other. The display device  1  includes a display panel  11 , a masking film  17 , a flexible printed circuit (FPC) board  12 , a backlight module  13  and an outer frame  14 . The display panel  11 , the masking film  17  and the backlight module  13  are stacked in that order from top to bottom, and accommodated in the outer frame  14 . One end of the FPC board  12  is mounted on one side of the display panel  11 , and another end of the FPC board  12  is connected to an external circuit (not shown) in order to provide display signals to the display panel  11 . 
         [0016]    The display panel  11  includes a display surface  112  and a back surface  114  parallel to each other. The backlight module  13  generates uniform light beams, and the light beams enter the display panel  11  via the back surface  114 . 
         [0017]    The FPC board  12  includes a baseboard  121  and a grounding pad  122 . The baseboard  121  is connected between the display panel  11  and the external circuit. The display signals, such as gray voltages, are transmitted to the display panel  11  via the baseboard  121 . The grounding pad  122  is arranged on a surface of the baseboard  121  facing towards the backlight module  13 , and is connected to ground via an earth wire in an electric plug (not shown) of the display panel  11 . 
         [0018]    The backlight module  13  includes at least one optical film  131  (only one is shown), a light guide plate  132 , an inner frame  133 , and a reflector  134 . The at least one optical film  131  is located above the light guide plate  132 . The inner frame  133  may be rectangular, and includes four sidewalls connected end-to-end to define a space accommodating the at least one optical film  131  and the light guide plate  132 . The reflector  134  is provided under the light guide plate  132 , and supported by the outer frame  14 . The inner frame  133  can be, for example, plastic. Due to tolerance during assembly of the backlight module  13 , a gap is defined between the inner frame  133  and the light guide plate  132 . Therefore, a masking film  17  is required to prevent light from exiting through the gap. 
         [0019]    The masking film  17  is a double-layer structure, including a conductive layer  15  stacked on a double-sided masking adhesive tape layer  16 . The conductive layer  15  can, for example, be a transparent or opaque conductive material, and includes a main body  151  and a connecting portion  152 . The main body  151  includes four strip sides (not labeled) connected end-to-end to form a rectangular frame shape. Thus the main body  151  can be attached to a peripheral region of the back surface  114  of the display panel  11 . The connecting portion  152  extends outward from the main body  151 , where the grounding pad  122  is located. The double-sided masking adhesive tape layer  16  has substantially the same shape as the main body  151 . One side of the double-sided masking adhesive tape layer  16  is attached to the main body  151 , thereby forming an integrated body with the conductive layer  15 . The other side of the double-sided masking adhesive tape layer  16  is configured to attach to the at least one optical film  131 , to avoid light leakage. 
         [0020]    Referring also to  FIG. 2  and  FIG. 3 , in assembly of the display device  1 , the main body  151  of the conductive layer  15  is attached to the peripheral region of the back surface  114  of the display panel  11 , and the connecting portion  152  of the conductive layer  15  is attached to the grounding pad  122  of the FPC board  12 . The light guide plate  132  and the at least one optical film  131  are accommodated in the inner frame  133  in that order, and the reflector  134  is adhered to a bottom supporting plate of the outer frame  14 . The combined masking film  17  and display panel  11  is adhered to a peripheral region of the at least one optical film  131 , such peripheral region corresponding to the gap between the inner frame  133  and the light guide plate  131 , with the adhesion being via the other side of the double-sided masking adhesive tape layer  16 . The display panel  11 , the backlight module  13  and the masking film  17  are accommodated in the outer frame  14  having the reflector  134 . 
         [0021]    Static electricity generated by friction may collect on the surfaces of the display panel  11 . Such static electricity can be discharged to ground via the main body  151  of the conductive layer  15 , the connecting portion  152  of the masking film  17 , and the grounding pad  122  of the FPC board  12  in that order, thereby protecting the display panel  11  from damage by ESD. Thus one layer of the masking film  17 , namely the conductive layer  15 , provides the masking film  17  with an anti-ESD function. At the same time, the other layer of the masking film  17 , namely the double-sided adhesive masking tape layer  16 , provides adherence as between the peripheral region of the display panel  11  and the backlight module  13 . That is, the double-sided adhesive masking tape layer  16  provides the masking film  17  with a light leakage prevention function to enhance the display quality of the display device  1 . Thus, the one masking film  17  advantageously has dual functions. 
         [0022]    Referring to  FIGS. 4 and 5 , a second embodiment of a display device of the present disclosure is shown. The display device may be an LCD, a light-emitting diode device, or other. The display device  2  differs from the display device  1  of the first embodiment only in that a connecting portion  252  of a conductive layer  25  extends from one side of a main body  251  different from another side of the main body  251  corresponding to an FPC board  22 . During assembly, the connecting portion  252  is folded along a corresponding side of an inner frame  233 , so that the connecting portion  252  is attached to an inner surface of an outer frame  24 . The outer frame  24  is made of metal, and is connected to ground by suitable means such as a grounding lead. Therefore, static electricity can be discharged to the outer metal frame  24  via the connecting portion  252 . 
         [0023]    Referring to  FIG. 6 , a third embodiment of a display device  3  of the present disclosure is shown. The display device may be an LCD, a light-emitting diode device, or other. The display device  3  has a structure similar to the display device  1  of the first embodiment, differing only in that a masking film  36  of the display device  3  is a single layer structure made of an opaque electrically conductive material. In this embodiment, a main body  361  and a connecting portion  362  have the same structure as the main body  151  and the connecting portion  152  of the display device  1 . Two surfaces of the main body  361  are attached to a peripheral region of a back surface  314  of a display panel  31 , and a corresponding region of the backlight module  33 , respectively. The connecting portion  362  is attached to a grounding pad  322  of an FPC board  32 . Alternatively, the main body  361  and the connecting portion  362  can have the same structure as the main body  251  and the connecting portion  252  of the display device  2 . In such case, the connecting portion  362  is attached to an inner surface of the outer frame  34 . Thus for the display device  3 , static electricity can be discharged either via the connecting portion  362  and the ground pad  322  (as illustrated in  FIG. 6 ), or via the connecting portion  362  and the outer frame  34  (no illustration). 
         [0024]    In the display device  3 , the single-layer masking film  36  not only discharges static electricity, but also prevents light leakage. Unlike in the display device  1 , no conductive layer is required for the masking film  36  of the display device  3 . Therefore the display device  3  can have a reduced thickness and reduced cost. 
         [0025]    It is to be understood, however, that even though numerous characteristics and advantages of the present embodiments have been set out in the foregoing description, together with details of the structures and functions of the embodiments, the disclosure is illustrative only; and that changes may be made in detail, especially in matters of shape, size and arrangement of parts within the principles of the disclosure to the full extent indicated by the broad general meaning of the terms in which the appended claims are expressed.