Abstract:
Provided is a flexible substrate wherein disconnection of wiring is suppressed, while reducing unnecessary radiation. A flexible substrate ( 10 ) is provided with a flexible base body ( 11 ), a plurality of wiring lines ( 12 ) formed on an inner surface ( 11   a ) of the base body, and a plurality of ground wiring lines ( 13 ) formed on an outer surface ( 11   b ) of the base body such that the ground wiring lines face the wiring lines ( 12 ). In a bent portion ( 11   c ) of the base body, the ground wiring lines are formed with a width smaller than that of the wiring lines ( 12 ).

Description:
TECHNICAL FIELD 
       [0001]    The present invention relates to a flexible substrate (a flexible circuit board) and a display device provided therewith, and particularly relates to a flexible circuit board that includes a base body having wiring lines formed on both sides thereof and a display device provided therewith. 
       BACKGROUND ART 
       [0002]    In recent years, electronic apparatuses have become compact and their performance has been improved, and this has raised a demand for reduction of unwanted radiation generated from circuit boards incorporated in electronic apparatuses. To fulfill the demand, there has been proposed, for example, a printed circuit board that includes a base body having wiring lines formed on both sides thereof (see, for example, Patent Literature 1 listed below). 
         [0003]    The above-mentioned Patent Literature 1 discloses a printed circuit board provided with a printed circuit base material (base body), a power supply pattern (a power supply wiring line) formed on a surface of the printed circuit base material on which an IC (integrated circuit) is to be mounted, and a ground pattern (a ground wiring line) formed on a rear surface of the printed circuit base material so as to be located opposite to the power supply pattern. 
         [0004]    In this printed circuit board, by forming the ground pattern on the rear surface of the printed circuit base material so as to be located opposite to the power supply pattern, the power supply pattern and the ground pattern can be electromagnetically coupled to each other. This makes it possible to reduce unwanted radiation generated from the power supply pattern (the printed circuit board). 
         [0005]    This printed circuit board makes it possible to reduce unwanted radiation generated from the power supply pattern (the printed circuit board) merely by forming the ground pattern on the rear surface of the printed circuit base material, and thus, with this printed circuit board, in comparison with a case where, for example, an electromagnetic wave absorbing tape or an EMC (electromagnetic compatibility) countermeasure component is additionally provided, unwanted radiation can be easily reduced without increase in size (weight) of the printed circuit board. 
         [0006]    Electronic apparatuses provided with a display device such as a liquid crystal display device have been conventionally known, and such electronic apparatuses incorporate a display panel and a flexible circuit board, which is flexible, the flexible circuit board being electrically connected to the display panel. 
         [0007]    A possible way to reduce unwanted radiation generated from such an electronic apparatus is to form the flexible circuit board to have the same structure as the printed circuit board disclosed in Patent Literature 1. 
         [0008]    That is, to form the flexible circuit board such that it includes a base body having flexibility, a power supply wiring line formed on one surface of the base body, and a ground wiring line formed on the other surface of the base body so as to be opposite to the power supply wiring line. In this way, it is possible to reduce unwanted radiation generated from the flexible circuit board (the electronic apparatus). 
       Citation List 
     Patent Literature 
       [0009]    Patent Literature 1: JP-A-H10-223997 
       SUMMARY OF INVENTION 
     Technical Problems 
       [0010]    However, if a flexible circuit board, which is flexible, is formed to have the same structure as the printed circuit board of Patent Literature 1, when the flexible circuit board is bent, a force is applied to a wiring line (a power supply wiring line or a ground wiring line) that is formed on an outside surface of the base body in a direction to stretch the wiring line. This leads to a possibility that the wiring line (the power supply wiring line or the ground wiring line) formed on the outside surface of the base body is broken, which is disadvantageous. 
         [0011]    The present invention has been made to solve the above problems, and an object of the present invention is to provide a flexible circuit board capable of capable of preventing break of wiring lines and capable of reducing unwanted radiation, and a display device provided therewith. 
       Solution to Problem 
       [0012]    To achieve the above object, according to a first aspect of the present invention, a flexible circuit board includes: a base body that is flexible and includes an inside surface that is located inside when the base body is in a bent state and an outside surface that is located outside when the base body is in the bent state; a set of a plurality of first wiring lines formed on the inside surface of the base body; and a set of a plurality of second wiring lines formed on the outside surface of the base body so as to be opposite to the first wiring lines. Here, one of the set of the first wiring lines and the set of the second wiring lines includes ground wiring lines; and in a bent portion of the base body, the second wiring lines are formed smaller than the first wiring lines in at least one of width and thickness. 
         [0013]    With the flexible circuit board according to the first aspect, as described above, by providing the plurality of first wiring lines on the inside surface of the base body and the plurality of second wiring lines on the outside surface of the base body so as to be opposite to the first wiring lines, and by structuring such that one of the set of the first wiring lines and the set of the second wiring lines includes the ground wiring lines, it is possible to electromagnetically couple the first wiring lines to the second wiring lines. With this structure, even in a case where the other of the set of the first wiring lines and the set of the second wiring lines includes a signal wiring line and a power supply wiring line, it is possible to reduce unwanted radiation generated from the other of the set of the first wiring lines and the set of the second wiring lines (specifically, from the signal wiring line and the power supply wiring line). 
         [0014]    With the flexible circuit board according to the first aspect, as described above, by forming the second wiring lines smaller than the first wiring lines in at least one of width and thickness in the bent portion of the base body, it is possible to make the second wiring lines easy to be stretched when the base body (the flexible circuit board) is bent. This helps prevent the second wiring lines from being broken. 
         [0015]    Furthermore, by forming the second wiring lines smaller than the first wiring lines in at least one of width and thickness in the bent portion of the base body, it is possible to prevent generation of a large reaction force when the base body (the flexible circuit board) is bent. That is, it is possible to prevent the base body (the flexible circuit board) from becoming difficult to be bent. 
         [0016]    Preferably, in the above-described flexible circuit board according to the first aspect described above, the first wiring lines include at least one kind of wiring line out of a signal wiring line, a power supply wiring line, and a ground wiring line, and the second wiring lines include the ground wiring lines. With this structure, the at least one kind of wiring line out of a signal wiring line, a power supply wiring line, and a ground wiring line formed on the inside surface of the base body can be easily connected to, for example, a display panel arranged inside from the flexible circuit board in a bent state. Furthermore, since the second wiring lines include the ground wiring lines, even if the second wiring lines (the ground wiring lines) formed on the outside surface of the base body should be broken when the base body is bent, the first wiring lines (the signal wiring line, the power supply wiring line, and the ground wiring line) will not be broken, and this, for example, helps prevent the display panel from ceasing to function properly. 
         [0017]    Preferably, in the flexible circuit board according to the first aspect described above, in the base body, a through hole is formed in a portion at a side where one-side ends of the first and second wiring lines are located, and the one-side ends of the second wiring lines are drawn out via the through hole toward the inside surface of the base body. This structure helps electrically connect both the first and second wiring lines easily to, for example, the display panel. As a result, when a current (a signal) flows through the other of the set of the first wiring lines and the set of the second wiring lines, it is easy to make a feedback current (a feedback signal) flow through the one of the set of the first wiring lines and the set of the second wiring lines (the ground wiring lines), and this makes it easy to electromagnetically couple the first wiring lines to the second wiring lines. As a result, unwanted radiation generated from the other of the set of the first wiring lines and the set of the second wiring lines (the signal wiring line, the power supply wiring line, etc.) can be easily reduced. 
         [0018]    Preferably, in the flexible circuit board having a through hole formed in the base body thereof, the second wiring lines include the ground wiring lines, and one-side ends of the ground wiring lines are connected to each other. With this structure, it is possible to draw out the ground wiring lines in a collective state toward the inside surface of the base body. This makes it possible to reduce increase in number of through holes formed for drawing out the ground wiring lines therethrough toward the inside surface of the base body, and thus to reduce increase in space for forming the through holes. Thus, the ground wiring lines can be easily drawn out toward the inside surface of the base body. 
         [0019]    In the flexible circuit board according to the first aspect described above, there may be formed a solid ground pattern in the base body, such that another-side ends of the ground wiring lines are connected to the solid ground pattern. 
         [0020]    According to a second aspect of the present invention, a display device includes: the flexible circuit board structured as described above; and a display panel that is electrically connected to the flexible circuit board. With this structure, it is possible to obtain a display device capable of preventing break of wiring lines and capable of reducing unwanted radiation. 
       Advantageous Effects of Invention 
       [0021]    As discussed hereinabove, according to the present invention, it is easy to obtain a flexible circuit board capable of preventing break of wiring lines and capable of reducing unwanted radiation and a display device provided with the flexible circuit board. 
     
    
     
       BRIEF DESCRIPTION OF DRAWINGS 
         [0022]      FIG. 1  A sectional view showing the structure of a liquid crystal display device provided with a flexible circuit board according to an embodiment of the present invention; 
           [0023]      FIG. 2  A perspective view showing the structure of the flexible circuit board and the liquid crystal display panel according to the embodiment of the present invention shown in  FIG. 1 ; 
           [0024]      FIG. 3  A plan view showing the structure of the flexible circuit board according to the embodiment of the present invention shown in  FIG. 1 ; 
           [0025]      FIG. 4  An enlarged see-through view showing the structure of wiring lines formed on an inside surface of the flexible circuit board according to the embodiment of the present invention shown in  FIG. 1 ; 
           [0026]      FIG. 5  An enlarged view showing the structure of wiring lines formed on an outside surface of the flexible circuit board according to the embodiment of the present invention shown in  FIG. 1 ; 
           [0027]      FIG. 6  A sectional view taken along line  100 - 100  in  FIG. 5 ; 
           [0028]      FIG. 7  A sectional view taken along line  200 - 200  in  FIG. 5 ; 
           [0029]      FIG. 8  A sectional view showing the structure of a flexible circuit board according to a first modified example of the present invention; and 
           [0030]      FIG. 9  A sectional view showing the structure of a flexible circuit board according to a second modified example of the present invention. 
       
    
    
     DESCRIPTION OF EMBODIMENTS 
       [0031]    Embodiments of the present invention will be described below with reference to the drawings. 
         [0032]    With reference to  FIGS. 1 to 7 , a description will be given of the structure of a liquid crystal display device  1  provided with a flexible circuit board  10  according to an embodiment of the present invention. The liquid crystal display device  1  is an example of a “display device” of the present invention. 
         [0033]    The liquid crystal display device  1  provided with the flexible circuit board  10  according to an embodiment of the present invention is used in electronic apparatuses such as portable phone terminals. In addition, as shown in  FIG. 1 , the liquid crystal display device  1  includes a liquid crystal display panel  2 , an upper polarization plate  3  and a lower polarization plate  4  between which the liquid crystal display panel  2  is placed, a backlight unit  20  arranged at a rear surface side (a lower side) of the liquid crystal display panel  2 , and a metal frame  5  that covers a rear surface side of the backlight unit  20 . The liquid crystal display panel  2  is an example of a “display panel” of the present invention. 
         [0034]    The liquid crystal display panel  2 , as shown in  FIG. 2 , includes a transparent AM substrate (active matrix substrate)  2   a  and a transparent counter substrate  2   b  that is arranged opposite to the AM substrate  2   a  and has a smaller area than the AM substrate  2   a . Between the AM substrate  2   a  and the counter substrate  2   b , unillustrated liquid crystal is sealed. The liquid crystal display panel  2  functions as a display panel by being illuminated by the backlight unit  20  (see  FIG. 1 ). 
         [0035]    The liquid crystal display panel  2  is, as shown in  FIG. 1 , adhered (fixed) to a front surface of a frame  25 , which will be described later, with an adhesive member  6 , which is, for example, a double-faced tape. 
         [0036]    To a front surface of the AM substrate  2   a , as shown in  FIGS. 1 and 2 , a driving IC  7  and the flexible circuit board  10  are fitted. 
         [0037]    The flexible circuit board  10  includes an insulating base body  11  that has flexibility and that also includes an inside surface  11   a  (see  FIG. 1 ) that is located inside when the flexible circuit board  10  is in a bent state (the state shown in  FIG. 1 ) and an outside surface  11   b  that is located outside when the flexible circuit board  10  is in the bent state. 
         [0038]    The base body  11  has a bent portion  11   c  (see  FIGS. 1 and 3 ) that is bent when the flexible circuit board  10  is incorporated in the liquid crystal display device  1 . 
         [0039]    As shown in  FIG. 4 , on the inside surface  11   a  of the base body  11 , there are formed a plurality of wiring lines  12 . These wiring lines  12  include signal wiring lines  12   a , power supply wiring lines  12   b , and ground wiring lines  12   c , and are arranged with a predetermined pitch in direction A. The wiring lines  12  are an example of “first wiring lines” of the present invention. 
         [0040]    The wiring lines  12  are formed so as to extend in direction B across the bent portion  11   c  of the base body  11 . One-side (direction B 1 -side) ends of the wiring lines  12  are electrically connected to a terminal (not shown) of the liquid crystal display panel  2 . 
         [0041]    On the other hand, as shown in  FIG. 3 , on the outside surface  11   b  of the base body  11 , there are formed a plurality of ground wiring lines  13  and a solid ground pattern  14 . The ground wiring lines  13  are an example of “second wiring lines” and “ground wiring lines” of the present invention. 
         [0042]    Here, according to the present embodiment, as shown in  FIGS. 5 and 6 , the plurality of ground wiring lines  13  are formed on the outside surface  11   b  of the base body  11  so as to be opposite to the plurality of wiring lines  12  (at least all of the signal wiring lines  12   a  and the power supply wiring lines  12   b ) (see  FIG. 6 ). That is, the ground wiring lines  13  are formed at positions right behind the wiring lines  12 . 
         [0043]    The plurality of ground wiring lines  13  are, as shown in  FIG. 6 , arranged in direction A with the same pitch as the wiring lines  12 . As shown in  FIG. 5 , the ground wiring lines  13  are formed in the same manner as the wiring lines  12 , that is, so as to extend in direction B across the bent portion  11   c  of the base body  11 . 
         [0044]    According to the present embodiment, as shown in  FIG. 6 , in the bent portion  11   c  of the base body  11 , a width W 2  of the ground wiring lines  13  is smaller than a width W 1  of the wiring lines  12 . Incidentally, according to the present embodiment, a thickness T 2  of the ground wiring lines  13  is equal to a thickness T 1  of the wiring lines  12 . 
         [0045]    According to the present embodiment, as shown in  FIG. 5 , one-side ends (direction B 1 -side ends) of the ground wiring lines  13  are connected to each other. 
         [0046]    According to the present embodiment, as shown in  FIGS. 5 and 7 , one-side ends (direction B 1 -side ends) of the ground wiring lines  13  are drawn out toward the inside surface  11   a  of the base body  11  via through holes  11   d  formed in a portion of the base body  11  close to one edge (direction B 1  side) thereof. That is, the one-side ends of the ground wiring lines  13  are connected via the through holes  11   d  to the ground wiring lines  12   c  included in the wiring lines  12 . As a result, the wiring lines  12  and the ground wiring lines  13  are both electrically connected to the liquid crystal display panel  2  (see  FIG. 2 ). 
         [0047]    As shown in  FIG. 3 , another-side ends (direction B 2 -side ends) of the ground wiring lines  13  are connected to the solid ground pattern  14 . 
         [0048]    The solid ground pattern  14  formed to range from a region closer to direction B 2  side than the bent portion  11   c  (a side opposite from the liquid crystal display panel  2 ) to a connector member connection region  11   e  to which a connector member (not shown) is connected. Incidentally, to the connector member (not shown), the solid ground pattern  14  (the ground wiring lines  13 ) and the wiring lines  12  (the signal wiring lines  12   a , the power supply wiring lines  12   b , and the ground wiring lines  12   c ) are electrically connected. 
         [0049]    As shown in  FIG. 1 , the backlight unit  20  is a side light type (edge light type) backlight unit, and includes a plurality of LEDs (light emitting diodes)  21 , a light guide plate  22  having a light receiving surface  22   a  for receiving light from the LEDs  21 , a plurality of optical sheets  23 , a reflection sheet  24  arranged at a rear surface side of the light guide plate  22 , and a resin frame  25  for housing these. 
         [0050]    The plurality of LEDs  21  are fixed on the inside surface  11   a  of the base body  11  (the flexible circuit board  10 ) via a solder layer  26 . 
         [0051]    The light guide plate  22  has a function of receiving light from the LEDs  21  through the light receiving surface  22   a  thereof and outputting light from a light outputting surface  22   b  thereof toward the liquid crystal display panel  2 . 
         [0052]    The plurality of optical sheets  23  are arranged to be in contact with the light guide plate  22 . The plurality of optical sheets  23  include, for example, a diffusion sheet  23   a  that has a function of diffusing light, and lower and upper lens sheets  23   b  and  23   c  that are arranged in front of the diffusion sheet  23   a  and have a function of collecting light. 
         [0053]    The reflection sheet  24  reflects light outputted from the rear surface of the light guide plate  22  to make the reflected light travel to the light guide plate  22 . 
         [0054]    The frame  25  houses the plurality of LEDs  21 , the light guide plate  22 , the plurality of optical sheets  23 , etc. 
         [0055]    According to the present embodiment, as described above, by forming a plurality of signal wiring lines  12   a  and power supply wiring lines  12   b  on the inside surface  11   a  of the base body  11 , and by forming a plurality of ground wiring lines  13  on the outside surface  11   b  of the base body  11  so as to be opposite to the signal wiring lines  12   a  and the power supply wiring lines  12   b , the signal and power supply wiring lines  12   a  and  12   b  can be electromagnetically coupled to the ground wiring lines  13 . This helps reduce unwanted radiation generated from the signal wiring lines  12   a  and the power supply wiring lines  12   b.    
         [0056]    Furthermore, according to the present embodiment, as described above, in the bent portion  11   c  of the base body  11 , by making the width W 2  of the ground wiring lines  13  smaller than the width W 1  of the wiring lines  12 , the ground wiring lines  13  formed on the outside surface  11   b  can be easily stretched when the base body  11  (the flexible circuit board  10 ) is bent. This helps prevent the ground wiring lines  13  from being broken. 
         [0057]    Moreover, by making the width W 2  of the ground wiring lines  13  smaller than the width W 1  of the wiring lines  12  in the bent portion  11   c  of the base body  11 , it is possible to prevent generation of a large reaction force when the base body  11  (the flexible circuit board  10 ) is bent. That is, the base body  11  (the flexible circuit board  10 ) can be prevented from becoming difficult to bend. 
         [0058]    According to the present embodiment, as described above, the signal wiring lines  12   a  and the power supply wiring lines  12   b  are formed on the inside surface  11   a  of the base body  11 , and the ground wiring lines  13  are formed on the outside surface  11   b  of the base body  11 . With this structure, even if the wiring lines (the ground wiring lines  13 ) formed on the outside surface  11   b  of the base body  11  should be broken, the signal wiring lines  12   a  and the power supply wiring lines  12   b  will not be broken, and this helps prevent the liquid crystal display panel  2  (the liquid crystal display device  1 ) ceasing to function properly. 
         [0059]    Furthermore, according to the present embodiment, as described above, by drawing out the one-side ends of the ground wiring lines  13  toward the inside surface  11   a  of the base body  11  via the through holes  11   d , both the wiring lines  12  and the ground wiring lines  13  can be electrically connected to the liquid crystal display panel  2  easily. This makes it easy to make a feedback current (a feedback signal) flow through the ground wiring lines  13  when a current (a signal) flows through the wiring lines  12  (the signal wiring lines  12   a  and the power supply wiring lines  12   b ), and thus, the wiring lines  12  (the signal wiring lines  12   a  and the power supply wiring lines  12   b ) can be electromagnetically coupled to the ground wiring lines  13  easily. As a result, unwanted radiation generated from the wiring lines  12  (the signal wiring lines  12   a  and the power supply wiring lines  12   b ) can be easily reduced. 
         [0060]    Moreover, according to the present embodiment, as described above, by connecting the one-side ends of the ground wiring lines  13  to each other, the ground wiring lines  13  can be drawn out in a collective state toward the inside surface  11   a  of the base body  11 . This makes it possible to reduce increase of the number of the through holes  11   d  provided for the ground wiring lines  13  to be drawn out toward the inside surface  11   a  of the base body  11  therethrough and to prevent increase in space for forming the through holes  11   d , and thus the ground wiring lines  13  can be easily drawn out toward the inside surface  11   a  of the base body  11 . 
         [0061]    The embodiment disclosed herein is to be considered in all respects as illustrative and not restrictive. The scope of the present invention is set out in the appended claims and not in the description of the embodiment hereinabove, and includes any variations and modifications within the sense and scope equivalent to those of the claims. 
         [0062]    For example, the above-described embodiment shows a case where the display device is applied to a liquid crystal display device, but this is not meant to limit the present invention, and application is possible to any type of display device other than a liquid crystal display device. 
         [0063]    The above-described embodiment shows a case where the flexible circuit board is connected to the liquid crystal display panel, but this is not meant to limit the present invention, and the flexible circuit board may be connected to a member other than the liquid crystal display panel. 
         [0064]    The above-described embodiment shows an example where the ground wiring lines  13 , which are formed on the outside surface  11   b  of the base body  11 , are formed such that they have a smaller width than the wiring lines  12  formed on the inside surface  11   a  of the base body  11 , but this is not meant to limit the present invention, and, for example, a first modified example of the present invention shown in  FIG. 8  or a second modified example of the present invention shown in  FIG. 9  may be adopted. Specifically, as shown in  FIG. 8 , in the bent portion  11   c , ground wiring lines  113  formed on the outside surface  11   b  of the base body  11  may be formed such that they have a thickness smaller than that of the wiring lines  12  formed on the inside surface  11   a  of the base body  11 . In this case as well, it is possible to reduce the risk of the ground wiring lines  113  being broken when the base body  11  (the flexible circuit board  10 ) is bent. Alternatively, as shown in  FIG. 9 , in the bent portion  11   c , ground wiring lines  213  formed on the outside surface  11   b  of the base body  11  may be formed such that they have a width and a thickness smaller than those of the wiring lines  12  formed on the inside surface  11   a  of the base body  11 . In this case, it is possible to further reduce the risk of the ground wiring lines  213  being broken when the base body  11  (the flexible circuit board  10 ) is bent. 
         [0065]    The above-described embodiment shows an example where the wiring lines  12  including the signal wiring lines  12   a , the power supply wiring lines  12   b , etc. are formed on the inside surface  11   a  of the base body  11  while the ground wiring lines  13  are formed on the outside surface  11   b  of the base body  11 , but this is not meant to limit the present invention, and the ground wiring lines  13  may be formed on the inside surface  11   a  of the base body  11  and the wiring lines  12  including the signal wiring lines  12   a , the power supply wiring lines  12   b , etc. may be formed on the outside surface  11   b  of the base body  11 . In this case, the through holes  11   d  may be provided on a one-to-one basis for the wiring lines  12  including the signal wiring lines  12   a , the power supply wiring lines  12   b , etc., and the wiring lines  12  including the signal wiring lines  12   a , the power supply wiring lines  12   b , etc. may be drawn out toward the inside surface  11   a  of the base body  11 . 
         [0066]    The above-described embodiment shows an example where the ground wiring lines  13  are formed to be located opposite to at least all the signal wiring lines  12   a  and the power supply wiring lines  12   b , but this is not meant to limit the present invention, and the ground wiring lines  13  do not need to be formed to be opposite to all of the signal wiring lines  12   a  and the power supply wiring lines  12   b . That is, the ground wiring lines  13  may be formed such that one ground wiring line  13  opposes each of ones of the signal wiring lines  12   a  and the power supply wiring lines  12   b  that are likely to generate unwanted radiation. 
         [0067]    The above-described embodiment shows an example where the wiring lines  12  formed on the inside surface  11   a  of the base body  11  include the signal wiring lines  12   a , the power supply wiring lines  12   b , and the ground wiring lines  12   c , but this is not meant to limit the present invention, and the wiring lines  12  may include only the signal wiring lines  12   a  and the power supply wiring lines  12   b . In other words, the ground wiring lines  12   c  do not need to be formed on the inside surface  11   a  of the base body  11 . In this case, for the purpose of connecting the ground wiring lines  13  to the liquid crystal display panel  2 , there may additionally be formed a pattern that functions as ground in part around the through holes  11   d  on the inside surface  11   a  of the base body  11 . 
         [0068]    The above-described embodiment shows an example where only the solid ground pattern  14  is provided on the outside surface  11   b  of the base body  11  to range from a region closer to direction B side (the side opposite from the liquid crystal display panel  2 ) than the bent portion  11   c  to the connector member connection region  11   e , but this is not meant to limit the present invention, and a signal wiring line or a power supply wiring line may be provided, for example, in part of the region of the outside surface  11   b  of the base body  11  where the solid ground pattern  14  is formed. That is, part of the signal wiring lines  12   a  and the power supply wiring lines  12   b  that are formed on the inside surface  11   a  of the base body  11  may be drawn out toward the outside surface  11   b  of the base body  11  via the through holes. With this structure, a space for fitting components such as a capacitor and a resistor can be easily secured on the inside surface  11   a  of the base body  11 . 
         [0069]    Reference Signs List
     1  liquid crystal display device (display device)     2  liquid crystal display panel (display panel)     10  flexible circuit board     11  base body     11   a  inside surface     11   b  outside surface     11   c  bent portion     11   d  through hole     12  wiring line (first wiring line)     12   a  signal wiring line     12   b  power supply wiring line     12   c  ground wiring line     13 ,  113 ,  213  ground wiring line (second wiring line, ground wiring line)     14  solid ground pattern