Abstract:
The present invention relates to an electric-field drive display device. According to one embodiment of the present invention, the electric-field drive display device comprises: a first substrate; a first electrode which is formed on the first substrate; a second electrode which is formed on the first substrate and is disposed in parallel with the first electrode; a drive partition wall which is formed on the first electrode and the second electrode and has a plurality of opening and closing holes; and a plurality of drive bodies which are disposed inside each of the opening and closing holes. Consequently, the electric-field drive display device according to one embodiment of the present invention can adjust the amount of light transmitted and so display the desired image by adjusting the positions of the drive bodies in the horizontal direction through the use of electrical force.

Description:
BACKGROUND OF THE INVENTION 
       [0001]    (a) Field of the Invention 
         [0002]    The present invention relates to a flat panel display, and more particularly, to a display device driven by electric field. 
         [0003]    (b) Description of the Related Art 
         [0004]    An example of a currently known flat panel display may include a liquid crystal display (LCD), a plasma display panel (PDP), an organic light emitting diode (OLED) display, a field effect display (FED), an eletrophoretic display, or the like. 
         [0005]    Among others, the liquid crystal display has been prevalently as a monitor, a television, etc., the plasma display panel has been as a large television, and the organic light emitting display is used for a mobile phone window, etc. Research into the organic light emitting display for applying to a mid-large sized display has been actively progressed. Research into other field effect display devices or the electrophorectic display device for applying to monitor, television, E-paper, has been progressed. 
         [0006]    In particular, as the display applied to the E-paper, the reflective electrophorectic display having similar texture to paper is used representatively; however, has disadvantages such as high driving voltage, slow response speed, and hard gray scale representation. In addition, in order to perform the color representation, there is a problem in that the reflective electrophorectic display necessarily uses a color filter. 
         [0007]    The above information disclosed in this Background section is only for enhancement of understanding of the background of the invention and therefore it may contain information that does not form the prior art that is already known in this country to a person of ordinary skill in the art. 
       SUMMARY OF THE INVENTION 
       [0008]    The present invention has been made in an effort to provide a display device driven by electric field with low driving voltage and improved response speed, as compared with E-paper of the related art. 
         [0009]    An exemplary embodiment of the present invention provides a display device driven by electric field, including: a first substrate; a first electrode formed on the first substrate; a second electrode formed on the first substrate and disposed in parallel with the first electrode; a driving barrier rib formed on the first electrode and the second electrode and having a plurality of opening and closing holes; and a plurality of driving bodies disposed in each opening and closing hole. 
         [0010]    The display device driven by electric field may further include a second substrate disposed on the driving barrier rib; and a light shielding layer formed on the second substrate. 
         [0011]    The opening and closing hole may include the light shielding unit and the light transmitting unit, wherein the light shielding layer is disposed at the light shielding unit. 
         [0012]    The display device driven by electric field may further include a color filter formed on the second substrate, corresponding to the light transmitting unit. 
         [0013]    The first electrode may be disposed at the light shielding unit and the second electrode may be disposed at the light transmitting unit. 
         [0014]    The display device driven by electric field may further include a first control electrode formed to overlap with the second electrode. 
         [0015]    The first control electrode may be formed on the same layer as the first electrode. 
         [0016]    The second electrode may have an opening exposing a portion of the first control electrode. 
         [0017]    The display device driven by electric field may further include a second control electrode adjacently formed to the same layer as the second electrode. 
         [0018]    A gap between the first electrode and the second electrode may be equal to or larger than the diameter of the driving body. 
         [0019]    The display device driven by electric field may further include a first insulating layer covering the first electrode, wherein the second electrode is formed on the first insulating layer. 
         [0020]    The driving body may be made of a non-transmitting material having charge. 
         [0021]    The position of the driving body may be determined by driving voltage applied to the first electrode and the second electrode. 
         [0022]    The first electrode and the second electrode may be applied with the driving voltage having different opposite polarities. 
         [0023]    The second electrode may be made of a transmitting conductive material. 
         [0024]    The driving body may move between the light shielding unit and the light transmitting unit when the driving voltage is applied thereto in order to open and close light. 
         [0025]    The first control electrode or the second control electrode may be applied with control voltage having opposite polarity to the driving voltage applied to the second electrode when the driving body is disposed at the light transmitting unit. 
         [0026]    The first control electrode or the second control electrode may be applied with control voltage having the same magnitude and polarity as the driving voltage applied to the second electrode when the driving body is disposed at the light shielding unit. 
         [0027]    The display device driven by electric field may further include a backlight unit supplying light for display to the first substrate. 
         [0028]    The opening and closing hole may include the light shielding unit and a reflector, the light shielding layer is disposed at the light shielding unit, and the reflector is further provided with a light absorbing layer. 
         [0029]    The display device driven by electric field may further include a first control electrode formed to overlap with the second electrode, wherein the light absorbing layer is formed below the first control electrode. 
         [0030]    The driving body may be made of a total reflection material having charges. 
         [0031]    The driving body may have any one of white, red, green, blue, yellow, magenta, and cyan. 
         [0032]    Light may be totally reflected when the driving body is disposed at the reflector. 
         [0033]    The opening and closing hole may include the light shielding unit and the reflector and the light shielding unit may be provided with the light shielding layer and the second electrode. 
         [0034]    The reflector may be provided with the first electrode, wherein the first electrode is made of a non-transmitting conductive material. 
         [0035]    The display device driven by electric field may further include: a second insulating layer having higher reflective index than the first insulating layer formed between the first insulating layer and the second electrode. 
         [0036]    Light reflected from the first electrode may be totally reflected at the interface between the first insulating layer and the second insulating layer. 
         [0037]    The driving body may be made of a total reflection material having charges. 
         [0038]    Another exemplary embodiment of the present invention provides a method for manufacturing a display device driven by electric field, the method including: forming a first electrode extending in a predetermined direction on a first substrate; forming a first insulating layer covering the first electrode; forming a second electrode on the second insulating layer in parallel with the first electrode; forming a driving barrier rib having a plurality of opening and closing holes on the first electrode and the second electrode; injecting a plurality of driving bodies in the opening and closing hole; and coupling a second substrate formed with a light shielding unit on the driving barrier rib. 
         [0039]    The method for manufacturing a display device driven by electric field may further include forming a first control electrode at a position overlapping with the second electrode on the same layer as the first electrode. 
         [0040]    The method for manufacturing a display device driven by electric field may further include forming a second control electrode at a position adjacent to the second electrode on the same layer as the second electrode. 
         [0041]    The method for manufacturing a display device driven by electric field may further include forming a color filter on the second substrate. 
         [0042]    A driving body made of a non-transmitting material having charges may be injected into the opening and closing hole and the light shielding layer may be formed at a position corresponding to the first electrode. 
         [0043]    A driving body made of a total reflection material having charges may be injected into the opening and closing hole and the light shielding layer may be formed at a position corresponding to the first electrode. 
         [0044]    The method for manufacturing a display device driven by electric field may further include forming a light absorbing layer below the first control electrode. 
         [0045]    A driving body made of a total reflection material having charges may be injected into the opening and closing hole and the light shielding layer may be formed at a position corresponding to the second electrode. 
         [0046]    The method for manufacturing a display device driven by electric field may further include forming a second insulating layer having higher reflective index than the first insulating layer on the first insulating layer. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0047]      FIG. 1  is a plan view showing a display device driven by electric field according to an exemplary embodiment of the present invention; 
           [0048]      FIG. 2  is a cross-sectional view taken along line II-II of the display device driven by electric field shown in  FIG. 1 ; 
           [0049]      FIGS. 3 to 5  are cross-sectional views sequentially showing a method for manufacturing the display device driven by electric field according to an exemplary embodiment of the present invention; 
           [0050]      FIG. 6  is a cross-sectional view of a display device driven by electric field according to another exemplary embodiment of the present invention; and 
           [0051]      FIG. 7  is a cross-sectional view of display device driven by electric field according to yet another exemplary embodiment of the present invention. 
       
    
    
     DETAILED DESCRIPTION OF THE EMBODIMENTS 
       [0052]    The present invention will be described more fully hereinafter with reference to the accompanying drawings, in which exemplary embodiments of the invention are shown. As those skilled in the art would realize, the described embodiments may be modified in various different ways, all without departing from the spirit or scope of the present invention. 
         [0053]    In the drawings, the thickness of layers, films, panels, regions, etc., are exaggerated for clarity. Like reference numerals designate like elements throughout the specification. It will be understood that when an element such as a layer, film, region, or substrate is referred to as being “on” another element, it can be directly on the other element or intervening elements may also be present. In contrast, when an element is referred to as being “directly on” another element, there are no intervening elements present. 
         [0054]    Hereinafter, a display device driven by electric field according to an exemplary embodiment of the present invention will be described with reference to  FIGS. 1 and 2 . 
         [0055]      FIG. 1  is a plan view showing a display device driven by electric field according to an exemplary embodiment of the present invention and  FIG. 2  is a cross-sectional view taken along line II-II of the display device driven by electric field shown in  FIG. 1 . 
         [0056]    As shown in  FIGS. 1 and 2 , a display device driven by electric field according to an exemplary embodiment of the present invention includes a display panel  100  and a backlight unit  400 . 
         [0057]    A display panel  100  is a part displaying images by controlling light amount. The display panel  100  includes a lower substrate  110  on which a first electrode  120  and a second electrode  130  are formed, an upper substrate  210  opposite to the lower substrate  110  and having a light shielding layer  220  thereon, a driving barrier rib  320  disposed between the lower substrate  110  and the upper substrate  210  and having a plurality of opening and closing holes  330 , and driving bodies  310  disposed in the opening and closing holes  330 . 
         [0058]    The first electrode  120  is formed on the transparent lower substrate  110  composed of a glass substrate, a flexible substrate, etc., while lengthily extending in a predetermined direction and the first control electrode  141  is disposed thereon in parallel with the first electrode in the same direction as the first electrode  120 . 
         [0059]    The first electrode  120  may be made of a transparent conductive material such as indium tin oxide (ITO), indium zinc oxide (IZO), etc., or an opaque conductive material such as Cr, Al, Mo, etc., and the first control electrode  141  may be made of a transparent conductive material such as indium tin oxide (ITO), indium zinc oxide (IZO), etc. 
         [0060]    Switching devices  125  for individually switching voltage applied to the first electrode  121  are formed on the lower substrate  110  and is connected to the first electrode  121 . As the switching device  125 , a thin film transistor may be used. In this case, the switching devices  125  may be formed on the lower substrate  110  in a type where a gate line (not shown) transferring a scan signal for turning-on and turning-off the thin film transistor and a data line (not shown) transferring a gray voltage applied to the first electrode  121  intersects with each other. The thin film transistor may include a gate electrode, a source electrode, a drain electrode, and semiconductor. 
         [0061]    A first insulating layer  150  is formed on the lower substrate  110 , the first electrode  120 , and the first control electrode  141 . The first insulating layer  150  has a single layer structure composed of an organic layer and may have photosensitivity. In addition, the first insulating layer  150  may be composed of an inorganic layer of silicon nitride, silicon oxide, etc., and may have a multilayer structure of an inorganic layer and an organic layer. 
         [0062]    The second electrode  130  is disposed on the first insulating layer  150  in parallel with the first electrode  120 . The second electrode  130  is disposed at a position where it overlaps with the first control electrode  141  and is provided with a plurality of openings  131  exposing a portion of the first control electrode  141  so that electric field from the first control electrode  141  is arrived at the driving bodies  310 . 
         [0063]    The second electrode  130  may be made of a transparent conductive material such as indium tin oxide (ITO), indium zinc oxide (IZO), or the like. 
         [0064]    In addition, the second control electrode  142  may be disposed on the first insulating layer  150  at a position where a driving barrier rib  320  is formed. The second control electrode  142  is adjacently positioned to the second electrode  130 , thereby making it possible to prevent the driving body  310  disposed on the second electrode  130  from flowing. 
         [0065]    The driving barrier rib  320  formed on the first insulating layer  150  may be formed by coating, exposing, and developing a photosensitive material. The driving barrier rib  320  may be made of an opaque material through which light is not transmitted. For example, the driving barrier rib  320  is made of a black color material to transmit or reflect unnecessary light, thereby making it possible to prevent the deterioration in display quality. 
         [0066]    The opening and closing hole  330  is a rectangular parallelepiped shape, wherein the cross section thereof is a rectangular shape. The opening and closing hole  330  is configured to include a light shielding unit S shielding light and a transmitting unit T transmitting light. 
         [0067]    The opening and closing hole  330  is provided with the driving body  310  having a spherical shape determined by an electric force. The driving body  310  has positive or negative charge. The driving body  310  may be made of a non-transmitting material of a black color to exclude the reflected light. A size of a diameter d 1  of the driving body  310  is several micrometer to several tens micrometer and may be equal to or less than a gap d 2  between the first electrode  120  and the second electrode  130 . 
         [0068]    Therefore, the driving body  310  has a small size and is thus operated at high speed due to a driving voltage of several voltages V. Therefore, the response speed of the driving body  310  is very rapid and the position of the driving  310  can be precisely controlled. Since the operating speed of the driving body  310  is in inverse proportion to a weight, the central portion of the driving body  310  is formed to have a cavity, thereby making it possible to reduce the weight of the driving body  310 . 
         [0069]    The width w of the opening and closing hole  330  may be larger than the diameter d 1  of the driving body  310  and the length L of the opening and closing hole  330  may be larger than the diameter dl of the driving body  310 . Therefore, when the driving voltage is applied, the driving body  370  may freely move in the space of the opening and closing hole  330 . 
         [0070]    The opening and closing hole  330  includes inert gas (not shown) such as argon, neon, helium, etc., together with the driving body  310 . The opening and closing hole  330  may be filled with other gas suitable for conserving charges owned by the driving body  310 , such as nitrogen or dried air, instead of the inert gas. In addition, the opening and closing hole  330  may be maintained in a vacuum state and may be filled with at least one of liquid without polarity or with a little polarity, solvent having small surface energy, and liquid crystal. 
         [0071]    The upper substrate  210  is disposed on the driving barrier rib  310 . A color filter  230  such as red, green, blue, etc., is formed at a position corresponding to the transmitting unit T on the upper substrate  210 . A passivation layer  250  is formed on the color filter  230  to protect the color filter  230 . A light shielding layer  220  is formed at a position corresponding to the light shielding unit S on the passivation layer  250 . The light shielding layer  220  may be made of a non-transmitting material. 
         [0072]    A backlight unit  400  supplies light to the display panel  100 . The backlight unit includes a lamp  420  emitting light, a light guide plate  410  converting light emitted from the lamp  420 , which is a linear light source or a point light source, into a surface light source, and a light collecting lens  430  collecting light from the light guide plate  410  and progressing the light to the opening and closing hole  330  that is a display region. As the lamp  420 , a linear light source such as a cold cathode fluorescent lamp (CCFL), an external electrode fluorescent lamp (EEFL), etc., or a point light source such a light emitting diode (LED), etc., may be used. Alternatively, a surface light source may also be used. In this case, the light guide plate  410  may be omitted. Further, the light collecting lens  430  may be directly formed on the surface of the light guide plate  410 , or may be formed thereon in a single layer, or a separate film type. Alternatively, the light collecting lens  430  may be formed on the display panel  100  in a single layer. The backlight unit  400  may be disposed on either the lower substrate  110  or the upper substrate  210 . 
         [0073]    An image display method and a method for controlling the driving bodies for the first and second control electrodes in the display device driven by electric field according to the exemplary embodiment of the present invention will be described below with reference to  FIGS. 1 and 2 . 
         [0074]    As shown in  FIGS. 1 and 2 , the display device driven by electric field applies an electric force to the driving bodies  310  included in the opening and closing hole  330  to move the positions of the driving bodies. When the driving voltage is applied to the first electrode  120  and the second electrode  130 , electric field is formed therebetween to apply the electric force to the driving bodies  310  having charges, such that the driving bodies  310  move in the opening and closing hole  330 . The first electrode  120  and the second electrode  130  are applied with the driving voltage having different opposite polarities. For example, when the driving body  310  has a positive charge, the first electrode  120  becomes a negative electrode and the second electrode  130  becomes a positive electrode, such that the driving bodies  310  move in the first electrode  120  direction and are positioned at the light shielding unit S. In addition, when the driving bodies  310  have a positive charge, the first electrode  120  becomes a positive electrode and the second electrode  130  becomes a negative electrode, such that the driving bodies  310  move in the second electrode  130  direction, positioned at the light transmitting unit T, and contact the second electrode  130 . As such, when the driving bodies  310  are applied with the driving voltage, they move between the light shielding unit S and the light transmitting unit T to open and close light emitted from the backlight unit  400 , thereby making it possible to display the desired images. 
         [0075]    In  FIG. 2 , portion A indicates that the driving bodies  310  of a non-transmitting material are positioned at the light emitting unit T to shield light emitted from the backlight unit  400  by the driving bodies  310 , thereby implementing a black state. Meanwhile, in  FIG. 2 , portion B indicates that the driving bodies  310  are positioned at the light shielding unit S to transmit light emitted from the backlight unit  400  as it is, thereby implementing colors of the color filter  230 . 
         [0076]    Meanwhile, the first control electrode  141  and the second control electrode  142  control the driving bodies  310  with the separate control voltage in order to prevent the flowing of the driving bodies. This will be described in detail below. 
         [0077]    When the driving bodies  310  are positioned at the light transmitting unit T to contact the second electrode  130 , the potential of the second electrode  130  is equal to that of the driving body  310 , such that the driving body  310  may be separated from the second electrode  130 . In order to prevent it, the first control electrode  141  is applied with the separate control voltage having different polarity from potential of the driving body  310  to apply attraction between the first control electrode  141  and the driving body  310 . Therefore, the driving body  310  maintains a state contacting the second electrode  130 . For example, when the second electrode  130  is the driving voltage of negative polarity of −5V, the driving body  310  contacting the second electrode  130  has the potential of the same magnitude, such that the driving body  310  may be separated from the second electrode  130 . Therefore, the first control electrode  141  is applied with the control voltage of a predetermined magnitude of positive polarity to apply attraction between the first control electrode  141  and the driving body  310 , such that the driving body  310  maintains a state in which it contacts the second electrode  130 . 
         [0078]    When the first control electrode  141  is applied with the control voltage having the same polarity and magnitude as those of the second electrode  130 , the driving body  310  contacting the second electrode  130  is separated from the second electrode  130  to move to the first electrode  120  disposed at the light shielding unit S. The driving body  310  moving to the light shielding unit S does not contact the first electrode  120  due to the first insulating layer  150  formed on the first electrode  120 , such that the driving body  310  is fixed to the light shielding unit S. 
         [0079]    Meanwhile, the second control electrode  142  is also applied with a predetermined control voltage, such that the driving body  310  may maintain a state in which it contacts the second electrode  130 . 
         [0080]    A method for manufacturing the display device driven by electric field according to the exemplary embodiment of the present invention will be described in detail with reference to  FIGS. 3 to 5 . 
         [0081]      FIGS. 3 to 5  are cross-sectional views sequentially showing a method for manufacturing the display device driven by electric field according to the exemplary embodiment of the present invention. 
         [0082]    First, as shown in  FIG. 3 , the first electrode  120  made of a transparent conductive material such as ITO or IZO, etc., or an opaque conductive material such as Cr, Al, Mo, etc., is formed on the lower substrate  110  composed of a glass substrate or a flexible substrate and the first control electrode  141  made of a transparent conductive material such as ITO or IZO, etc., is sequentially formed on the same layer. The first insulating layer  150  covering the first electrode  120  and the first control electrode  141  is formed on the same layer. The second electrode  130  made of a transparent conductive material such as ITO or IZO is formed on the first insulating layer  150  and the second control  142  made of the transparent conductive material such as ITO or IZO, etc. or the opaque conductive material such as Cr, Al, Mo, etc., is sequentially formed on the same layer. 
         [0083]    Next, as shown in  FIG. 4 , the barrier ribs  320  partitioning a plurality of driving regions  330  are formed and the plurality of driving bodies  310  are injected into the plurality of driving regions  330 . In this case, a mixture of the driving bodies  310  may be injected into the driving region, together with at least one of liquid without polarity or with a little polarity, solvent having small surface energy, and liquid crystal. In addition, the driving body  310  may be injected by using a thin metal tip coated with the insulating layer. 
         [0084]    Next, as shown in  FIG. 5 , the upper substrate  210  on which the color fitter  230 , the passivation layer  250 , and the light shielding layer  220  are formed is coupled with the lower substrate  110 , thereby completing the display panel  100 . The backlight unit  400  is coupled with the lower substrate  110 , thereby completing the display device driven by lateral electric field. 
         [0085]    Although the present exemplary embodiment describes the transmission display driven by electric field displaying the desired image by opening and closing light provided by the backlight unit  400 , a structure for preventing the flowing of the driving body  310  using the separate first and second control electrodes may be applied even when the reflective display device driven by electric field displaying the desired images by opening and closing the external light. 
         [0086]    The reflective display device driven by electric field implementing a black state by using a light absorbing layer will be described in detail with reference to  FIG. 6 . 
         [0087]      FIG. 6  is a cross-sectional view of a display device driven by electric field according to another exemplary embodiment of the present invention. 
         [0088]    The present exemplary embodiment is substantially the same as the exemplary embodiments shown in  FIGS. 1 and 2  except for only the structure in which the driving body made of the total reflection material having colors and the light absorbing layer are formed in order to use the external light and therefore, the repeated description thereof will be omitted. 
         [0089]    As shown in  FIG. 6 , the display device driven by electric field according to another exemplary embodiment of the present invention has only the display panel  100  and does not have the backlight unit  400 . 
         [0090]    The light absorbing layer  170  made of a non-transmitting material is formed on the lower substrate  110  of the display panel  100 . The light absorbing layer  170  may be formed at a position corresponding to a reflector R. 
         [0091]    The second insulating layer  160  is formed on the light absorbing layer  170  and the first electrode  120  and the first control electrode  141  are disposed on the second insulating layer  160 . The first insulating layer  150  is formed on the second insulating layer  160 , the first electrode  120 , and the first control electrode  141 . The second electrode  130  is disposed on the first insulating layer  150  in parallel with the first electrode  120  and the driving barrier rib  320  having the opening and closing hole  330  is formed on the first insulating layer  150 . The opening and closing hole  330  includes the light shielding unit S shielding light and the reflector R reflecting light. The light shielding unit S may be formed at a position in which it overlaps with the first electrode  120  and the reflector R may be formed at a position in which it overlaps with the second electrode  130 . The opening and closing hole  330  is disposed with the driving body  310  having a spherical shape of which the position is determined by an electric force. The driving body  310  has a positive or negative charge. The driving body  310  may be made of a material capable of totally reflecting light and may have any one selected from white, red, green, blue, yellow, magenta, and cyan. Therefore, a separate color filter is not required. 
         [0092]    The upper substrate  210  is coupled on the driving barrier  310 . The passivation layer  250  is formed on the upper substrate  210  and the light shielding layer  220  is formed at a position corresponding to the light shielding unit S on the passivation layer  250 . 
         [0093]    The reflective display device driven by electric field controls the external amount of light reflected by the driving body  310 , thereby implementing images. That is, as shown in portion A of  FIG. 6 , when the driving body  310  is disposed at the reflector R, the external light is totally reflected by the driving body  310  made of the total reflection material, such that the colors are implemented by the colors of the surface of the driving body  310 . In addition, as in portion B of  FIG. 6 , when the driving body  310  is disposed at the light shielding unit S, the external light is absorbed into the light absorbing layer  170 , such that the black state is implemented. 
         [0094]    As described above, the black state may be implemented by totally absorbing the external light by using the light absorbing layer  170  but the second insulating layer  170  having higher refractive index is formed on the first insulating layer  150  to totally reflect the external light, thereby making it possible to implement the black state. 
         [0095]    The reflective display device driven by electric field implementing the black state using the total reflection will be described below with reference to  FIG. 7 . 
         [0096]      FIG. 7  is a cross-sectional view of a display device driven by electric field according to yet another exemplary embodiment of the present invention. 
         [0097]    The present exemplary embodiment is substantially the same as the exemplary embodiment shown in  FIG. 6  except that it does not require the separate light absorbing layer and the position of the second insulating layer is different and therefore, the repeated description thereof will be omitted. 
         [0098]    As shown in  FIG. 7 , the display device driven by electric field according to another exemplary embodiment of the present invention has only the display panel  100  and does not include the backlight unit  400 . 
         [0099]    The first electrode  120  and the first control electrode  141  are disposed on the lower substrate  110  of the display panel  100 . The first insulating layer  150  is formed on the lower substrate  110 , the first electrode  120 , and the first control electrode  141 . The second insulating layer  160  having the higher reflective index than that of the first insulating layer  150  is formed on the first insulating layer  150 . The second electrode  130  is disposed on the second insulating layer  160  in parallel with the first electrode  120  and the driving barrier rib  320  having the opening and closing hole  330  is formed on the second insulating layer  160 . The opening and closing hole  330  includes the light shielding unit S shielding light and a reflector R capable of reflecting light. The light shielding unit S may be formed at a position in which it overlaps with the second electrode  130  and the reflector R may be formed at a position in which it overlaps with the first electrode  120 . The opening and closing hole  330  is disposed with the driving body  310  having a spherical shape of which the position is determined by the electric force. The driving body  310  has a positive or negative charge. The driving body  310  may be made of a material capable of totally reflecting light and may have any one selected from white, red, green, blue, yellow, magenta, and cyan. Therefore, a separate color filter is not required. 
         [0100]    The upper substrate  210  is coupled on the driving barrier rib  310 . The passivation layer  250  is formed on the upper substrate  210  and the light shielding layer  220  is formed at the position corresponding to the light shielding unit S on the passivation layer  250 . 
         [0101]    The reflective display device driven by electric field controls the external amount of light reflected by the driving body  310 , thereby implementing the images. In other words, as in portion A of  FIG. 7 , when the driving body  310  is disposed at the light shielding unit S, the external light is not reflected, thereby implementing the black state. That is, the external light passes through the second insulating layer  160  and the first insulating layer  150  and some thereof is absorbed in the first electrode  120  and some thereof is reflected from the first electrode  120 . The reason is that the first electrode  120  is made of an opaque metal. Some light reflected from the first electrode  120  is totally reflected at the interface between the second insulating layer  160  and the first insulating layer  150 . In order to implement the total reflection, the second insulating layer  160  may have the higher reflective index than the first insulating layer  150 . Therefore, the external light is not emitted to the front surface, thereby implementing the black state. In addition, as in portion B of  FIG. 7 , when the driving bodies  310  is positioned at the reflector R, the external light is totally reflected by the driving body  310  made of the total reflection material, such that colors are implemented by the colors of the surface of the driving body  310 . 
         [0102]    According to the present invention, the positions of the driving bodies are controlled in a horizontal direction by using the electric force formed in a horizontal direction to control the transmittance of light, thereby making it possible to display the desired image. 
         [0103]    In addition, the present invention can prevent the flowing of the driving bodies by forming the first control electrode below the second electrode or forming the second control electrode beside the second electrode to store the information and display the images when the final driving voltage is applied, thereby making it possible to give the conservation like the printed matters, etc. 
         [0104]    In addition, the present invention can precisely control the positions of the driving bodies by using the first and the second control electrode to more precisely control the transmittance of light passing through the driving region, thereby making it possible to implement the precise image. 
         [0105]    While this invention has been described in connection with what is presently considered to be practical exemplary embodiments, it is to be understood that the invention is not limited to the disclosed embodiments, but, on the contrary, is intended to cover various modifications and equivalent arrangements included within the spirit and scope of the appended claims.