Patent Abstract:
A liquid crystal display panel  10  of the present invention includes an array substrate  11  with a display region in which a pixel electrode is formed in each of the regions enclosed by a plurality of signal lines and scan lines deployed as matrices, a opposed substrate  12  with a common electrode  31 , a sealing agent  35  sealing a peripheral portion of the array substrate  11  and the opposed substrate  12 , a liquid crystal layer sealed between both substrates, a border region  34  including a reflector  37  and a transparent electrode  38  is formed on an interlayer  23  at a periphery of the display region of the array substrate  11 , and at least a part of an outer peripheral side is lacking from the common electrode  31  at a position corresponding to the border region  34 . Thanks to such structure, the border region improves the appearance at the periphery of the display region, and the phenomenon of night vision alongside the scan line wiring does not occur.

Full Description:
BACKGROUND 
       [0001]    1. Technical Field 
         [0002]    The present invention relates to a liquid crystal display panel. More particularly the present invention relates to a liquid crystal display panel having an ornamental reflective part (border region) for improving the appearance around the periphery of the display region, wherein dark lines do not appear alongside the scan line wiring in the border region. 
         [0003]    2. Related Art 
         [0004]    Over recent years the application of liquid crystal display panels has spread rapidly, not only in information and telecommunications equipment but in electrical equipment in general. Since liquid crystal display panels do not themselves emit light, the transmissive type of liquid crystal display panel that is equipped with a backlight is much employed. 
         [0005]    However, since backlights consume large amounts of power, the reflective type of liquid crystal display panel which does not need a backlight have been used, especially for portable equipment, in order to reduce power consumption. But reflective liquid crystal display panels use external light as light source and therefore are difficult to view in dark interiors of rooms, etc. Accordingly, in recent times particular progress has been made with the development of liquid crystal display panels of a semi-transmissive type, which possess the capabilities of both the transmissive and reflective types. 
         [0006]    Having, in each pixel region, a transmissive part equipped with a pixel electrode and a reflective part equipped with both a pixel electrode and a reflection electrode, in dark places semi-transmissive liquid crystal display panels display images by lighting a backlight and utilizing the transmissive part of the pixel region, and in bright places by utilizing external light via the reflective part, without lighting the backlight. Thus, such panels have the advantages of not needing to light the backlight always, and of being able to drastically reduce power consumption. 
         [0007]    A specific example of a related-art semi-transmissive liquid crystal display panel is described below using  FIGS. 4 to 6 .  FIG. 4  is a schematic plan view of a related-art single-terminal type semi-transmissive liquid crystal display panel,  FIG. 5  is a plan view of one pixel portion of the array substrate in  FIG. 4 , and  FIG. 6  is a cross-sectional view along VI-VI in  FIG. 5 . In  FIG. 4 , the non-display region around the periphery of the display region is depicted in an exaggerated manner for the sake of comprehension of the invention. Also, as used herein the term “display region” refers to the planar region where the pixel electrode is formed and where the alignment of the liquid crystal layer (the liquid crystal molecules) is controlled via the electric field applied to the pixel electrode, while the term “non-display region” refers to the planar region where no pixel electrode is formed and where the alignment of the liquid crystal layer, if present, is not controlled. 
         [0008]    A related-art semi-transmissive liquid crystal display panel  10 A has an array substrate  11  and a opposed substrate  12  that are opposed to each other and hold a liquid crystal layer between them. On the array substrate  11  there are formed, in the display region  14  on a transparent substrate  13  of glass or the like, parallel and equally-spaced multiple scan lines  17  constituted of aluminum, molybdenum or similar metal. Moreover, the scan lines  17  are coupled, via scan line wiring  17   1 , to a driver circuit placement portion  16  that is provided in the frame region  15  at the periphery of the display region  14 . Further, auxiliary capacitance line  18  is formed roughly centrally between adjacent scan lines  17  so as to be parallel to the scan lines  17 , and in addition, a gate electrode G for TFTs is drawn out from the scan lines  17 . Further, common wiring is provided on the transparent substrate  13 , but is omitted from the drawings. 
         [0009]    Also, a gate insulator  19  constituted of silicon nitride, silicon oxide or the like is laid over the entire surface of the transparent substrate  13  so as to cover the scan lines  17 , auxiliary capacitance line  18  and gate electrode G, and a semiconductor layer  20  constituted of amorphous silicon, polycrystalline silicon or the like is laid over the gate electrode G, with the gate insulator  19  interposed. Further, a plurality of signal lines  21  constituted of a metal such as aluminum or molybdenum are formed over the gate insulator  19  so as to be orthogonal to the scan lines  17 , and the plurality of signal lines  21  are likewise connected, via signal line wiring  21   1 , to the driver circuit placement portion  16 . Also, a source electrode S for TFTs is drawn out from these signal lines  21  so as to contact with the semiconductor layer  20 , and furthermore, a drain electrode D of the same material as the signal lines  21  and source electrode S are provided on the gate insulator  19 , likewise so as to contact with the semiconductor layer  20 . 
         [0010]    Each region enclosed by the two adjacent scan lines  17  and two adjacent signal lines  21  is equivalent to 1 pixel. TFTs that serve as switching elements are constituted by the gate electrode G, gate insulator  19 , semiconductor layer  20 , source electrode S and drain electrode D, one TFT being formed for each pixel. The auxiliary capacitance of each pixel is formed by the drain electrode D and auxiliary capacitance line  18 . 
         [0011]    A protective insulator (also termed passivation film)  22  of for example an inorganic insulating material is deposited over the whole surface of the transparent substrate  13  so as to cover the signal lines  21 , TFTs and gate insulator  19 . Over this protective insulator  22 , an interlayer (also termed a flattening film)  23  constituted of organic insulator is deposited so as to extend over the entire transparent substrate  13 . A contact hole  24  is formed in the protective insulator  22  and the interlayer  23  in position corresponding to the drain electrode D of the TFTs. Further, in each pixel a reflector  27  partially constituted of aluminum or similar metal is formed in the TFT and auxiliary capacitance line  18  side, and a pixel electrode  26  constituted of for example ITO (indium tin oxide) or IZO (indium zinc oxide) is formed on the surfaces of the reflector  27 , contact hole  24  and interlayer  23 . An orientation film (not shown in the drawings) is deposited over the surface of the pixel electrode  26  in such a manner as to cover all of the pixels. 
         [0012]    The opposed substrate  12  is another transparent substrate  28  constituted of glass plate or the like, for example, on the surface of which a color filter layer  29  composed of red (R), green (G) and blue (B), corresponding to individual pixels, is provided at least in a position corresponding to the display region  14  of the array substrate  11 . A top coat layer  30  is deposited on the surface of this color filter layer  29  in at least the position corresponding to the region where the reflector  27  is provided, in other words to the reflective part, of the array substrate  11 , and furthermore, a counter electrode  31  and an orientation film (not shown in the drawings) are deposited on the surface of the top coat layer  30  and color filter layer  29 . The top coat layer  30  is provided in order to cause the distance (the cell gap) between the pixel electrode  26  and the common electrode  31  at the reflective part to be approximately ½ the cell gap at the transmissive part where no reflector  27  is provided, and in order that the color tone at the reflective part and at the transmissive part will be equivalent. The color filter layer  29  may, where appropriate, be used in combination with a color filter layer of cyan (C), magenta (M) and yellow (Y), etc., while in the case of a monochrome display, it may be that no color filter layer is provided. 
         [0013]    The semi-transmissive liquid crystal display panel  10 A is then obtained by: positioning opposite each other the array substrate  11  and opposed substrate  12  obtained in the foregoing manner; sealing with sealing agent  35  the peripheries of the array substrate  11  and opposed substrate  12 ; electrically coupling the common wiring of the array substrate  11  and the common electrode of the counter substrate  12  via a transfer electrode (not shown); injecting liquid crystal into the space between the two substrates through a liquid crystal injection hole (not shown); and sealing the liquid crystal injection hole. 
         [0014]    In such semi-transmissive liquid crystal display panel  10 A, a backlight (not shown) is deployed on the array substrate  11  side; in dark places the backlight is lighted and the requisite images are displayed by means of light transmitted through the semi-transmissive liquid crystal display panel  10 A, while in bright places the requisite images are displayed by utilizing reflected external light, without lighting the backlight. But if the reflector is provided over the entire rear surface of each pixel electrode  26 , a reflective liquid crystal display panel will be obtained. In such a semi-transmissive liquid crystal display panel or reflective liquid crystal display panel, the reflector  27  is in some cases provided on the surface of the pixel electrode  26 , and it is common practice, for the sake of achieving good reflection efficiency at the reflective part and also of producing satisfactory white displays, to provide concavoconvexities on the surface of the interlayer  23  at the places where the reflector is provided, with the purpose of making the reflected light into diffuse reflected light. 
         [0015]    In a related art semi-transmissive liquid crystal display panel or reflective liquid crystal display panel such as described above, the non-display region around the periphery of the display region is covered over by a light-blocking black matrix and an outer cover, so that essentially the display region alone will be visible to viewers. For example, in the related art semi-transmissive liquid crystal display panel  10 A shown in  FIG. 4 , the non-display region  33  has at least the hatched portions covered over by a black matrix and the outer cover, so that the display portion  14  alone is visible to the viewer. 
         [0016]    In recent years however, there have come into use liquid crystal display panels in which, in order to improve the appearance, a reflective part that reflects external light is formed in the non-display region around the periphery of the display region, and such non-display region with reflective part formed therein is used for ornament. In a semi-transmissive liquid crystal display panel  10 B that uses for ornament such non-display region with reflective part formed therein, the non-display area  33  is covered by the black matrix and outer cover and is invisible to the viewer, whereas the portion of the non-display region  34  where the reflective part is formed is visible to the viewer, as shown in  FIG. 7 .  FIG. 7  is a schematic plan view of a semi-transmissive liquid crystal display panel  10 B that uses for ornament a non-display region with a reflective part formed therein; here too, the non-display region around the periphery of the display area is depicted in an exaggerated manner. Structural elements in  FIG. 7  that are the same as those of semi-transmissive liquid crystal display panel  10 A in  FIG. 4  are assigned identical reference numerals, and detailed descriptions thereof are omitted. 
         [0017]    At this portion of the non-display region  34  where the reflective part is formed, no pixel electrode is provided and therefore the orientation of the liquid crystal molecules does not vary. Hence such portion is seen by the viewer as being the same color as the color filter layer, provided on the opposed substrate  12 , corresponding to such portion. Usually, the color filter layer provided for such portion will be of the same kind as that formed in the display region  14 , so that such portion will effectively appear white in color. To have such portion of the non-display region  34  where the reflective part is formed appear in a satisfactory white color, it is necessary, as in a reflective or semi-transmissive liquid crystal display panel, to employ almost the same reflective display structure as in the reflective part of the display region. To that end, concavoconvexities are provided on the surface of the interlayer that underlies the reflectors. Below, such ornamental portion of the non-display region  34  where the reflective part is formed is termed the “border region” and is assigned the same reference numeral “34” when described. 
         [0018]    JP-A-2003-228049 discloses a reflective or semi-transmissive liquid crystal display panel in which the concavoconvexities provided on the surface of the interlayer at the reflective part of the display region are also provided in the non-display region, with the purpose of lessening display irregularities due to occurrence of unevenness in the cell gap near the boundary between the display region and non-display region. However, no mention is made therein of making part of the non-display region into a border region such as described above. 
         [0019]    In a semi-transmissive liquid crystal display panel  10 B having a border region  34  such as described above, the border region  34 , while undergoing no change in display status, nevertheless is able to exert an aesthetic ornamental effect whereby the periphery of the display region  14  appears white at all times, so that the appearance is greatly enhanced. However, detailed investigation by the present inventors revealed that in a semi-transmissive liquid crystal display panel  10 B having a border region  34  such as described above, dark lines appear alongside the scan line wiring  17   1  in the areas X enclosed by dashed lines on either side of the display region  14  in  FIG. 7 . 
         [0020]    Upon conducting a series of various investigations into the causes of the occurrence of the night vision phenomenon alongside the scan line wiring  17   1  of the border region in such a liquid crystal display panel having a border region  34 , the present inventors discovered that it was due to causes described below.  FIG. 8  is a cross-sectional view of the frame region  15  along line VIII-VIII in the semi-transmissive liquid crystal display panel  10 B of  FIG. 7 . In this frame region  15 , plural scan line wirings  17   1  and common wirings  40  are formed on the surface of the transparent substrate  13  on the array substrate  11  side, and the scan line wirings  17   1  and common wirings  40  are covered by a gate insulator  19  and protective insulator  22 . Further, in the border region  34  the surface of the protective insulator  22  is covered by an interlayer  23 , and columnar spacers  39  for keeping the cell gap constant are deployed at appropriate intervals around the edge portions. Also, the peripheral portions of the array substrate  11  and opposed substrate  12  are sealed with sealing agent  35 . 
         [0021]    The region on the opposed substrate  12  where the black matrix  36  is provided forms the non-display region  33 , and the area between the non-display region  33  and the display region  14  forms the border region  34 . The surface of the interlayer  23  of the border region  34  is formed to have concavoconvexities, and on such concavoconvex surface of the interlayer  23  is formed a reflector  37  constituted of for example aluminum metal; furthermore, a transparent electrode  38  constituted of ITO or IZO is formed on the surface thereof, and the surfaces of both the reflector  37  and the transparent electrode  38  are formed to be concavoconvex. For the sake of balance with the process for producing the dummy electrode for static protection in the related art, the reflector  37  and the transparent electrode  38  are, as shown in  FIG. 9 , deposited with the same pitch as the reflector  37  and pixel electrode  26  of the display region  14 , in an isolated condition such that the reflector  37  and the transparent electrode  38  are not electrically coupled to anything and are in a floating state. A black matrix is formed on the opposed substrate  12  in such a manner as to block light at the positions corresponding to the peripheries of each pixel electrode  26  of the display region  14  and of each transparent electrode  38  in the border region  34  of the array substrate  11 , but is omitted in  FIG. 8 .  FIG. 9  is an enlarged schematic view of the top left portion of the array substrate in the liquid crystal display panel  10 B of  FIG. 7 . 
         [0022]    Thus, it might be supposed that the portions of the border region  34  alongside the scan line wiring  17   1  ought not to appear dark, because the liquid crystal molecules present between the transparent electrode  38  and the opposed electrode  31  do not move, since there is no electric potential difference between the transparent electrode  38  and the opposed electrode  31 , as no potential is generated in the transparent electrode  38 , which is in a floating state. Yet, since the voltage applied to the scan line wiring  17   1  is high AC voltage (for example ±15V), the voltage applied between the scan line wiring  17   1  and the opposed electrode  31  is divided and voltage is generated in the transparent electrode  38 , so that a voltage V LC  is applied between the transparent electrode  38  and the opposed electrode  31 , and due to such voltage V LC  the alignment of the liquid crystal molecules between the transparent electrode  38  and the opposed electrode  31  varies, with the result that the phenomenon of dark appearance occurs alongside the scan line wiring  17   1  in the border region  34 . The voltage that is applied to the signal line wiring  21   1  is far lower than that applied to the scan line wiring  17   1  and therefore effectively does not exert any influence on the liquid crystal molecules in the border region  34 . 
         [0023]    The voltage V LC  that occurs between the transparent electrode  38  and the opposed electrode  31  will now be described using  FIG. 10 . The average thickness L 1  of the interlayer  23  between the scan line wiring  17   1  and the transparent electrode  38  is approximately 1.45 μm, and the permittivity ε of the polyimide normally used for the interlayer  23  is 3.4, so that a capacitor C S  with the interlayer  23  as dielectric body arises between the scan line wiring  17   1  and the transparent electrode  38 . Further, the average distance L 2  between the transparent electrode  38  and the opposed electrode  31  is approximately 2.0 μm, and the permittivity Δε of the liquid crystal layer generally used is approximately 7, so that a capacitor C LC  with the liquid crystal layer as dielectric body arises between the transparent electrode  38  and the opposed electrode  31 . 
         [0024]    This means that the voltage V 0  that is applied between the scan line wiring  17   i  and the opposed electrode  31  is divided by the series circuits of the capacitor C S  that arises between the scan line wiring  17   1  and the transparent electrode  38 , and of the capacitor C LC  that arises between the transparent electrode  38  and the opposed electrode  31 , so that the voltage V LC  expressed by equation (1) below is applied between the transparent electrode  3  and the opposed electrode  31 . As an example, where the voltage V 0  applied between the scan line wiring  17   1  and the opposed electrode  31  is 15V, V LC  will be approximately 6 V. 
         [0000]    
       
         
           
             
               
                 
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       SUMMARY 
       [0025]    As a result of various investigations aimed at resolving the night vision phenomenon alongside the scan line wiring  17   1  of the border region  34  due to the foregoing causes, the inventors have found that the phenomenon of the border region  34  appearing dark along the scan line wiring  17   1  as described above is not generated, when there is no potential difference between the opposed electrode  31  and the transparent electrode  38 . However, it was difficult to adopt such a structure immediately, because of increase in manufacturing steps and manufacturing cost. By conducting further research, the inventors have found that when at least an outer peripheral side, or more preferably, all of the opposed electrode  31  at a position corresponding to the border region  34  does not exist, a state that the electric field is not applied to the liquid crystal molecules can be created. This enables to eliminate the phenomenon that the border region  34  appears dark along the scan line wirings  17   1 , thereby completing the present invention. 
         [0026]    An advantage of some aspects of the invention is to provide a liquid crystal display panel having a border region around the periphery of the display region, in which night vision phenomena will not occur in such border region. 
         [0027]    According to an aspect of the invention, a liquid crystal display panel includes: an array substrate that has a display region in which a plurality of signal lines and scan lines deployed as matrices, plus signal line wiring and scan line wiring connected to the signal lines and scan lines respectively, plus common wiring, are provided on a transparent substrate, an insulator is coated over the surface of these, and a pixel electrode is formed in each of the regions on the insulator that are enclosed by the plurality of signal lines and scan lines; a opposed substrate that has a common electrode; and a liquid crystal layer that is sealed between the array substrate and the opposed substrate by means of sealing agent that seals together the peripheries of the two substrates. It also includes an ornamental reflective part including a reflector being deployed around the periphery of the array substrate&#39;s display region; the outer edges of the ornamental reflective part being sealed by the sealing agent, and at least a part of an outer peripheral side not being provided to the common electrode at a position corresponding to the ornamental reflective part. 
         [0028]    According to the above liquid crystal display panel of the invention, at least a part of the outer peripheral side is not being provided to the common electrode at the position corresponding to the ornamental reflective part. As there is no electric field applied to the liquid crystal layer by a signal voltage being applied to the scan line wiring, it does not appear dark with lines along the scan line wiring as in the related art. As a result, the liquid crystal display panel having the ornamental reflective part, that is, the border region, with an attractive appearance in white which uses reflection of external light by the reflector can be obtained. In such a case, by not providing all the common electrodes at the position corresponding to the ornamental reflective part, the electric field applied to the liquid crystal layer by the signal voltage being applied to the scan line wiring can be eliminated substantially and completely. But taking into account the likelihood of influence from electrostatic charges from outside, and to prevent the common electrode corresponding to the display region from misplacing by a mask misalignment during manufacturing, it is preferable not to provide at least a part of the outer peripheral side of the common electrode at the position corresponding to the ornamental reflective part. 
         [0029]    In the above liquid crystal display panel, preferably, a transparent electrode is formed on a surface or a rear surface of the reflector. 
         [0030]    According to the above liquid crystal display panel, there is no need to adopt a special manufacturing method or a manufacturing step anew, so that the common electrode at the position corresponding to the ornamental reflective part does not provide a part of the outer peripheral side. As a result, the liquid crystal display panel having the border region which produces a good ornamental effect can be obtained with ease without increasing manufacturing steps. 
         [0031]    Further, in the above liquid crystal display panel, the reflector of the ornamental reflective part may have a concavoconvex structure. 
         [0032]    According to the above liquid crystal display panel, the pixel electrode is formed in the display region. As the pixel electrode is formed by the transparent electrode, the structure of the ornamental reflective part can be made approximately the same as the structure of the display region, when the transparent electrode is also formed to the ornamental reflective part. As a result, a difference in appearance between the display region and the ornamental reflective part is reduced, and the liquid crystal display panel having the border region which produces a good ornamental effect can further be obtained. 
         [0033]    Moreover, a reflector with a concavoconvex structure may be formed on part or whole of the front surface or rear surface of the pixel electrode. 
         [0034]    According to the above liquid crystal display panel, light entered from outside becomes diffused reflected light, as the reflector of the ornamental reflective part has the concavoconvex structure. As a result, it looks pure white, and the liquid crystal display panel which produces a good ornamental effect can be obtained. 
         [0035]    Also, in the above liquid crystal display panel, it is possible, not only for the transmissive type of liquid crystal display panel but also for the semi-transmissive or the reflective type, to obtain a liquid crystal display panel that yields an ornamental effect with a fine white appearance. 
     
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0036]    The invention will be described with reference to the accompanying drawings, wherein like numbers reference like elements. 
           [0037]      FIG. 1  is a schematic plan view of a single-terminal type semi-transmissive liquid crystal display panel according to the first embodiment. 
           [0038]      FIG. 2  is a cross-sectional view along line II-II in  FIG. 1 . 
           [0039]      FIG. 3  is a sectional view of a modification of the single-terminal type semi-transmissive liquid crystal display panel corresponding to  FIG. 2 . 
           [0040]      FIG. 4  is a schematic plan view of a related-art single-terminal type semi-transmissive liquid crystal display panel. 
           [0041]      FIG. 5  is a plan view of one pixel portion of the array substrate in  FIG. 4 . 
           [0042]      FIG. 6  is a sectional view taken along the line VI-VI of  FIG. 5 . 
           [0043]      FIG. 7  is a schematic plan view of a liquid crystal display panel that uses for ornament a non-display region with a reflective part formed therein. 
           [0044]      FIG. 8  is a sectional view taken along the line VIII-VIII of  FIG. 7 . 
           [0045]      FIG. 9  is a schematic partially enlarged view of an upper left side of the liquid crystal display panel of  FIG. 7 . 
           [0046]      FIG. 10  is an equivalent circuit diagram explicating the voltage V LC  that occurs between the transparent electrode and the common electrode. 
       
    
    
     DESCRIPTION OF EXEMPLARY EMBODIMENTS 
       [0047]    Preferred embodiments of the invention will now be described with reference to the accompanying drawings. It should be borne in mind however that the following embodiments are merely illustrative examples of semi-transmissive liquid crystal display panels that realize the technical concepts of the invention. The embodiments are not intended to limit the invention to these particular semi-transmissive liquid crystal display panels. The invention can equally well be adapted to transmissive or reflective liquid crystal display panels and other embodiments contained within the scope of the claims. 
       First Embodiment 
       [0048]    A semi-transmissive liquid crystal display panel  10  of a first embodiment is described below using  FIGS. 1 to 2 .  FIG. 1  is a schematic plan view of a single-terminal type semi-transmissive liquid crystal display panel according to the first embodiment.  FIG. 2  is a cross-sectional view along line II-II in  FIG. 1 . Since the configuration of the pixels in the display region of the array substrate in the semi-transmissive liquid crystal display panel  10  of the first embodiment is substantially the same as that of the related art items shown in  FIGS. 5 and 6 , component elements that are identical to those in the related art cases are assigned the identical reference numerals, and where necessary are described with the aid of  FIGS. 5 and 6 . 
         [0049]    The semi-transmissive liquid crystal display panel  10  of the first embodiment has an array substrate  11  and a opposed substrate  12  that are opposed to each other and hold a liquid crystal layer between them. The array substrate  11  has a transparent substrate  13  on which are formed, equally spaced and in parallel, a plurality of scan lines  17  in the display region  14 . The a plurality of scan lines  17  are coupled via scan line wiring  17   1  to a driver circuit placement portion  16  that is provided in the frame region  15  at the periphery of the display region  14 . Further, auxiliary capacitance line  18  is formed in roughly central positions between adjacent scan lines  17  so as to be parallel to the scan lines  17 , and moreover a gate electrode G for TFTs are drawn out from the scan lines  17 . In addition, common wiring  40  is provided on the transparent substrate  13 . 
         [0050]    Also, a gate insulator  19  is deposited over the entire surface of the transparent substrate  13  so as to cover the scan lines  17 , auxiliary capacitance line  18  and gate electrode G, a semiconductor layer  20  is formed over the gate electrode G with the gate insulator  19  interposed, a plurality of signal lines  21  are formed on the gate insulator  19  so as to be orthogonal to the scan lines  17 , and the plurality of signal lines  21  are likewise coupled to the driver circuit placement portion  16  via signal line wiring  21   1 . Moreover, a source electrode S for TFTs are drawn out from the signal lines  21  so as to contact with the semiconductor layer  20 , and in addition, a drain electrode D is provided on the gate insulator  19  so as likewise to contact with the semiconductor layer  20 . 
         [0051]    Each region enclosed by the scan lines  17  and signal lines  21  is equivalent to 1 pixel, and in each pixel there is formed a TFT. A protective insulator  22  is deposited over the entire surface of the transparent substrate  13  so as to cover the signal lines  21 , TFTs and gate insulator  19 , and on the protective insulator  22  is deposited an interlayer  23  extending over the whole of the transparent substrate  13 . Also, contact hole  24  are formed in the protective insulator  22  and interlayer  23  in positions corresponding to the TFTs&#39; drain electrode D. Further, in each pixel there are formed a TFT plus, along part of the auxiliary capacitance line  18 , a reflector  27  constituted of for example aluminum metal, and on the surfaces of the reflector  27 , contact hole  24  and interlayer  23 , a pixel electrode  26  constituted of for example ITO or IZO is formed. An alignment layer (not shown) is deposited over the surface of the pixel electrode  26  so as to cover all the pixels. In the example described here the interlayer  23  is deposited over the entire surface of the transparent substrate  13 , but alternatively the interlayer might not be formed, in which case the contact hole  24  would be formed in the protective insulator  22 , and the reflector  27  and pixel electrode  26  would be formed thereon. 
         [0052]    The periphery of the display region  14  constitutes the frame region  15 . In the frame region  15 , the surface of the interlayer  23  that is adjacent to the display region  14  is formed with concavoconvexities, but part of such periphery is formed with a flat surface. On the portions of the interlayer  23 &#39;s surface that are formed with concavoconvexities, a reflector  37  and a transparent electrode  38  are formed in an integrated manner. Thus, as shown in  FIG. 1 , the frame region  15  of the array substrate  11  in the present embodiment has, viewed from above, a border region  34  that is formed around the periphery of the display region  14  and covered with the reflector  37  and the transparent electrode  38 ; furthermore, at the periphery thereof there is a non-display region  33 . In view of manufacturing steps of a dummy electrode for electrostatic protection of the related art, as the one of the related art shown in  FIG. 9 , the reflector  37  and the transparent electrode  38  are separated in a state that the reflector  37  and the transparent electrode  38  are disposed at the same pitch as the pixel electrode  26  of the display region  14 . The reflector  37  and the transparent electrode  38  are not electrically coupled to anywhere, being in a floating state. 
         [0053]    The opposed substrate  12  is constituted of another transparent substrate  28 , on which a black matrix  36  is formed in a position corresponding to the non-display region  33  of the array substrate  11 . Besides that, a black matrix is also provided so as to shade at least the periphery of the pixel electrode  26  in the display region  14  of the array substrate  11 , but is omitted from  FIG. 2 . In the transmissive liquid crystal display panel  10  of the first embodiment, there is no actual need to provide a black matrix in a position corresponding to the border region  34 , but to avoid any need to change the manufacturing method used in the related art, such black matrix (not shown in the drawings) for the border region  34  is nonetheless provided. Further, a color filter layer  29  is provided in positions corresponding to at least the display region  14  and border region  34  of the array substrate  11 , so as to correspond to the individual pixels. In at least the position on the surface of the color filter layer  29  of the display region  14  that correspond to the reflective part, a top coat layer  30  is deposited that is for causing the reflective part&#39;s cell gap to be roughly ½ the transmissive part&#39;s cell gap, so that the color tone at the reflective part and at the transmissive part will be equivalent. Further, a common electrode  31  and an alignment layer (not shown in the drawings) are deposited over the surface of the top coat layer  30  and color filter layer  29 . In the liquid crystal display panel  10  of the present embodiment, as shown in  FIG. 2 , the top coat layer  30  is provided to the entire border region  34 . However, the common electrode  31  is provided at a range slightly stretching over the border region  34  from the display region  14 , and it is not provided to an outer edge side of the border region. 
         [0054]    The array substrate  11  and the common substrate  12  obtained as above are made to oppose to each other. A rib  39  which is to maintain the cell gap at a fixed value is disposed accordingly, and the periphery is sealed by a sealing agent  35 . The common wiring  40  provided to the common electrode  31  and the array substrate  11  interposing another transfer electrode (not shown) therebetween, is electrically coupled. A liquid crystal is injected from a liquid crystal injection hole (not shown) formed by the sealing agent  35 . After the liquid crystal injection hole is sealed, the semi-transmissive liquid crystal display panel  10  of the embodiment can be obtained. 
         [0055]    Therefore, according to the semi-transmissive liquid crystal display panel  10  of the embodiment, the reflector  37  and the transparent electrode  38  provided to the border region  34  are not electrically coupled to anywhere, being in a floating state. As the common electrode  31  does not substantially exist at a portion where the opposed substrate  12  is opposed to the reflector  37  and the transparent electrode  38 , an electric field is not applied to the liquid crystal molecules existing in the border region  34 . Because the liquid crystal molecules existing in the border region  34  are not affected by electric potential of the scan line wiring  17   1  provided under the interlayer  23 , thereby eliminating the phenomenon that the border region  34  appears dark along the scan line wiring  17   1  as the related art. Therefore, according to the semi-transmissive liquid crystal display panel  10  of the embodiment, the semi-transmissive liquid crystal display  10  having the border region  34  which produces an attractive ornamental effect in white can be obtained. 
         [0056]    Normally, the common electrode  31  should only be provided at a position corresponding to the display region  14 . However, it is difficult only to provide at the position exactly corresponding to the display region  14 , when a mask misalignment during manufacturing and the like are taken into account. As the common electrode  31  is required at least at the position corresponding to the display region  14 , as shown in  FIG. 2 , it is preferable to cover a portion of the border region  34  slightly, so as the common electrode  31  will not be provided at a part of the outer peripheral side of the border region  34 . 
         [0057]    According to the liquid crystal display panel  10  of the embodiment, there is no need to adopt a special step anew not to provide a part of the outer peripheral side of the common electrode  31  at the position corresponding to the border region  34 . The liquid crystal display panel having the border region which produces the ornamental effect in white can be obtained with ease, without increasing manufacturing steps or a special wiring. 
         [0058]    Further, according to the liquid crystal display panel  10  of the present embodiment, the position on the periphery of the opposed substrate that correspond to the border region  34  is covered by a black matrix  36 . This means that although the display region  14  and border region  34  will be clearly visible from the exterior, the outer periphery of the border region  34  will not be visible from the exterior. Thus, the border region  34 &#39;s outer periphery, which has no ornamental effect, is rendered invisible from the exterior, with the result that a liquid crystal display panel  10  can be obtained that has a border region  34  that exerts an ornamental effect with good appearance by utilizing the external light reflected by the reflector  37 . 
         [0059]    Also, although the example in the first embodiment is a case where the inner surface of the portion of the opposed substrate  12  that correspond to the non-display region  33  is covered with a black matrix  36  to block light, the invention is not limited to this. Light could alternatively be blocked by providing the black matrix on the outer side of the opposed substrate  12 , or the outer cover could be used to shade the opposed substrate  12 . However, since the black matrix formation process is contained in the formation of the color filter layer  29  of the opposed substrate  12 , the black matrix  36  can be formed at the same time as such black matrix formation, and therefore it will be preferable to shade the inner surface of the portion of the opposed substrate  12  that correspond to the non-display region  33  by covering them with the black matrix  36 . Moreover, such will preferably be combined with use of the outer cover to shade the outer side of the opposed substrate  12 , in the interest of protecting the frame region of the semi-transmissive liquid crystal display panel  10 . 
         [0060]    According to the semi-transmissive liquid crystal display panel  10  of the embodiment, an example of providing the concavoconvex structure to the surface of the interlayer  23  of the border region  34  is shown. When the concavoconvex structure is smoothed and made flat, some ornamental effect can be achieved, as it becomes a mirror plane. However, as a boundary between the display region  14  and the border region becomes highly visible, it is more attractive in white by providing the concavoconvex structure, if not expecting a special effect. 
         [0061]    Further, according to the semi-transmissive liquid crystal display panel  10  of the embodiment, an example of forming the transparent electrode  38  on the surface of the reflector  37  positioned at least at the border region  34  is shown. However, in the liquid crystal display panel of the present invention, if the reflector  37  exists at least at the border region  34 , the same advantage can be produced even if the transparent electrode  38  does not exist.  FIG. 3  shows a sectional view of a modification of the semi-transmissive liquid crystal display panel  10 ′ corresponding to  FIG. 2 , which does not provide the transparent electrode on the reflector  37  at the border region  34 . A structure of the modification of the liquid crystal display panel  10 ′ shown in  FIG. 3  does not differ from that of the liquid crystal display panel  10  of the embodiment shown in  FIG. 2 , except that the transparent electrode does not exist on the surface of the reflector  37 . Therefore, the same components as those of the liquid crystal display panel  10  of the embodiment are denoted by the same reference numerals and the detailed description thereof are omitted.

Technology Classification (CPC): 6