Abstract:
A plasma display panel capable of stabilizing a discharge characteristic by integrating discharge cells with a high density and efficiently exhausting the plasma display panel is provided. The plasma display panel is constructed with: first and second substrates facing each other; barrier ribs disposed between the first and second substrates to define discharge cells; address electrodes extending in a first direction and corresponding to the discharge cells; and first and second electrodes extending in a second direction that crosses the first direction and corresponding to the discharge cells. The red, green, and blue discharge cells among the discharge cells are disposed in a triangular shape. Exhaust paths are formed between neighboring discharge cells.

Description:
CLAIMS OF PRIORITY 
       [0001]    This application makes reference to, incorporates the same herein, and claims all benefits accruing under 35 U.S.C. §119 from an application for PLASMA DISPLAY PANEL earlier filed in the Korean Intellectual Property Office on 29 Mar. 2006 and there duly assigned Serial No. 10-2006-0028286. 
       BACKGROUND OF THE INVENTION 
       [0002]    1. Field of the Invention 
         [0003]    The present invention relates to a plasma display panel, and more particularly, to a plasma display panel capable of stabilizing a discharge characteristic by integrating discharge cells with a high density in the plasma display panel and efficiently performing an exhausting process in the plasma display panel. 
         [0004]    2. Description of the Related Art 
         [0005]    In general, a plasma display panel is an element for displaying images by using visible light of red, green, and blue generated by exciting a florescent material by using vacuum ultra-violet (VUV) rays emitted from plasma obtained through gas discharge. 
         [0006]    For example, in an alternating current (AC) type plasma display panel, address electrodes are formed on a rear substrate and are covered with a dielectric layer. Barrier ribs are disposed between neighboring address electrodes. The barrier ribs have a stripe shape. Phosphor layers of red, green, and blue are formed on the barrier ribs. Display electrodes including a pair of sustain and scan electrodes are formed in a direction that crosses the address electrodes on a front substrate that faces the rear substrate and are covered with a dielectric layer and an MgO passivation film. The discharge cells are formed at positions where a pair of the address electrodes on the rear substrate cross a pair of the display electrodes on the front substrate. In the plasma display panel, more than millions of discharge cells are arranged in a matrix shape. 
         [0007]    A memory characteristic is used to drive the plasma display panel. More specifically, a voltage, which is greater than a certain voltage required for inducing discharge, is applied between a pair of the sustain and scan electrodes. The certain voltage represents a firing voltage (Vf). When a scan voltage and an address voltage are respectively applied to the scan and address electrodes, plasma is generated in the discharge cells. Electrons and ions of the plasma move toward electrodes having polarities opposite to the electrons and the ions. 
         [0008]    On the other hand, since each electrode of the plasma display panel is covered with the dielectric layer, most of the moved space charges are accumulated in the dielectric layer having a polarity opposite to the space charges. Finally, net space charge between the scan and address electrodes becomes less than the applied address voltage Va. Accordingly discharge weakens. Address discharge disappears. At this time, a relatively small amount of electrons are accumulated in the sustain electrode while a relatively large amount of electrons are accumulated in the scan electrodes. The charges accumulated in the dielectric layer that covers the sustain and scan electrodes are referred to as wall charges. A voltage between the sustain and scan electrodes caused by the wall charges is referred to as a wall voltage Vw. 
         [0009]    Subsequently, when a discharge sustain voltage Vs is applied to the sustain and scan electrodes, in a case where a value (Vs+Vw) obtained by adding the discharge sustain voltage Vs to the wall voltage Vw is greater than the firing voltage Vf, sustain discharge is carried out in the discharge cells. The VUV rays generated at this time excite the corresponding phosphor material. The excited phosphor material emits the visible light through the transparent front substrate. 
         [0010]    When there is no address discharge between the scan and address electrodes (that is, when the address voltage Va is not applied), however, the wall charges are not accumulated between the sustain and scan electrodes. Finally, there are no wall charges between the sustain and scan electrodes. At this time, only a discharge sustain voltage Vs applied to the sustain and scan electrodes is maintained in the discharge cells. Since the discharge sustain voltage is less than the firing voltage Vf, discharge cannot be carried out in a space filled with a gas between the sustain and scan electrodes. 
         [0011]    In a process of exhausting and sealing the plasma display panel among processes of manufacturing the plasma display panel, it is possible to carry out the gas discharge by exhausting the space between the front and rear substrates and filling the space with a discharge gas. 
         [0012]    On the other hand, the plasma display panel is formed by integrating the discharge cells of red, green, and blue with a high density so as to obtain a super extended resolution (for example, a resolution of 1920*1080). 
         [0013]    For example, there is a plasma display panel in which discharge cells are integrated with a high density by forming the discharge cells in a hexagonal shape and disposing another hexagonal discharge cell at each side of a hexagonal discharge cell. 
         [0014]    Since the discharge cells are integrated into the plasma display panel with a high density, however, impurities undesirably remain between the discharge cells. The impurities cause discharge irregularity and local luminance non-uniformity. 
       SUMMARY OF THE INVENTION 
       [0015]    It is therefore an object of the present invention to provide an improved plasma display panel. 
         [0016]    It is another object to provide a plasma display panel capable of stabilizing a discharge characteristics. 
         [0017]    According to an aspect of the present invention, there is provided a plasma display panel comprising: a first substrate; a second substrate facing the first substrate; barrier ribs disposed between the first and second substrates to define discharge cells; address electrodes extending in a first direction and corresponding to the discharge cells; and first and second electrodes extending in a second direction that crosses the first direction and corresponding to the discharge cells. The red, green, and blue discharge cells among the discharge cells may be disposed in a triangular shape. Exhaust paths may be formed between neighboring discharge cells. 
         [0018]    In the above aspect of the present invention, the discharge cells may have a rhombic shape with diagonals in the first and second directions. 
         [0019]    In addition, the barrier ribs may define discharge cells that are separate from one another along both the x-axis and the y-axis directions. 
         [0020]    In addition, the exhaust paths may be formed in third and fourth directions. Both of the third and fourth directions cross the first and second directions. The third direction may be orthogonal to the fourth direction. 
         [0021]    In addition, the barrier ribs of the discharge cells disposed along the second direction may be connected to one another, and the barrier ribs of the discharge cells disposed along the first direction may be spaced apart from one another to form the exhaust paths between the barrier ribs. 
         [0022]    In addition, the barrier ribs of the discharge cells disposed along the first direction maybe connected to one another, and the barrier ribs of the discharge cells disposed along the second direction may be spaced apart from one another to form the exhaust paths between the barrier ribs. 
         [0023]    In addition, a ratio of a diagonal length of the discharge cell in the first direction to a diagonal length the discharge cell in the second direction may range from approximately 1 to approximately 1.5. 
         [0024]    In addition, a width of the barrier ribs may be smaller than a width of the exhaust paths. 
         [0025]    In addition, the first and second electrodes may be covered with a dielectric layer, and the dielectric layer and the barrier ribs may be in a subtractive color mixture relation. 
         [0026]    In addition, the dielectric layer and the barrier ribs may be in a complementary color relation. 
         [0027]    In addition, the dielectric layer may be colored with blue, and the barrier ribs may be colored with red or brown. 
         [0028]    In addition, the barrier ribs may include: a pair of first barrier ribs that extend in a third direction crossing the first and second directions, spaced apart from one another and corresponding to each discharge cell in a fourth direction which is perpendicular to the third direction; and a pair of second barrier ribs that extend in the fourth direction, spaced apart from one another and corresponding to each discharge cell in the third direction. 
         [0029]    In addition, the pair of the first barrier ribs and the pair of the second barrier ribs may form discharge cells that have a rhombic shape and that are separate from one another in the first and second directions. 
         [0030]    In addition, the pair of the first barrier ribs and the pair of the second barrier ribs of the discharge cells disposed along the second direction may be connected to each other or cross each other. The pair of the first barrier ribs and the pair of the second barrier ribs of the discharge cells disposed along the first direction are spaced apart from each other to form the exhaust paths. And the discharge cells have a rhombic shape. 
         [0031]    In addition, the exhaust paths may have a zigzag shape along the third and fourth directions alternately. 
         [0032]    In addition, the pair of the first barrier ribs and the pair of the second barrier ribs of the discharge cells disposed along the first direction maybe connected to each other or cross each other. The pair of the first barrier ribs and the pair of the second barrier ribs of the discharge cells disposed along the second direction are spaced apart from each other to form the exhaust paths. And the discharge cells have a rhombic shape. 
         [0033]    In addition, the exhaust paths may have a zigzag shape along the third and fourth directions alternately. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0034]    A more complete appreciation of the invention and many of the attendant advantages thereof, will be readily apparent as the same becomes better understood by reference to the following detailed description when considered in conjunction with the accompanying drawings in which like reference symbols indicate the same or similar components, wherein: 
           [0035]      FIG. 1  is a perspective view schematically illustrating a plasma display panel constructed as a first embodiment according to the principles of the present invention by exploding the plasma display panel; 
           [0036]      FIG. 2  is a cross sectional view taken along line II-II′ of  FIG. 1 ; 
           [0037]      FIG. 3  is a top plan view illustrating an arrangement of barrier ribs and discharge cells of  FIG. 1 ; 
           [0038]      FIG. 4  is a top plan view illustrating an arrangement of barrier ribs and discharge cells according to a second embodiment of the principles of the present invention; and 
           [0039]      FIG. 5  is a top plan view illustrating an arrangement of barrier ribs and discharge cells according to a third embodiment of the principles of the present invention. 
       
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
       [0040]      FIG. 1  is a perspective view schematically illustrating a plasma display panel according to a first embodiment of the present invention by exploding the plasma display panel.  FIG. 2  is a cross sectional view taken along line II-II′ of  FIG. 1 . 
         [0041]    Referring to  FIGS. 1 and 2 , the plasma display panel according to the first embodiment of the principles of the present invention is constructed with a first substrate  10  (hereinafter, referred to as “rear substrate”) and a second substrate  20  (hereinafter, referred to as “front substrate”) which are sealed to face each other with a certain gap, and a barrier rib  16  which is disposed between first and second substrates  10  and  20 . 
         [0042]    Barrier rib  16  is formed with a certain height to define a plurality of discharge cells  17  between rear and front substrates  10  and  20 . 
         [0043]    Discharge cells  17  are filled with a discharge gas (for example, a gas mixture including neon (Ne) and xenon (Xe)) so as to generate vacuum ultraviolet rays through gas discharge. Each discharge cell  17  includes a phosphor layer  19  which emits visible light by absorbing the vacuum ultraviolet rays. 
         [0044]    The plasma display panel according to the embodiment of the present invention includes address electrodes  11 , first electrodes  31  (hereinafter, referred to as “sustain electrodes”) and second electrodes  32  (hereinafter, referred to as “scan electrodes”), that correspond to discharge cells  17  between rear and front substrates  10  and  20 . 
         [0045]    For example, each address electrode  11  extends along a first direction (y-axis direction of  FIGS. 1 and 2 ) on an inner surface  12  of rear substrate  10  to correspond to neighboring discharge cells  17  in the y-axis direction. In addition, a plurality of address electrodes  11  are disposed in parallel with each other along a second direction (x-axis direction of  FIGS. 1 and 2 ) which crosses the y-axis direction to correspond to neighboring discharge cells  17  in the x-axis direction. 
         [0046]    Address electrodes  11  are covered with a dielectric layer  13  which also covers the inner surface of rear substrate  10 . Dielectric layer  13  prevents damages of address electrodes  11  by preventing positive ions or electrons from directly colliding against address electrodes  11 . Dielectric layer  13  generates wall charges. The wall charges are accumulated in dielectric layer  13 . Since address electrodes  11  are disposed on rear substrate  10 , address electrodes  11  do not block visible light which is irradiated toward the front side. Accordingly, address electrode  11  maybe made from an opaque material such as a metal that has high electrical conductivity. 
         [0047]    Barrier rib  16  is disposed on dielectric layer  13  to define discharge cells  17 . Discharge cells  17  are classified into red (R), green (G), and blue (B) discharge cells  17 R,  17 G, and  17 B, which are three sub pixels. The three sub pixels constitute one pixel. 
         [0048]    On the other hand, dielectric layer  13  and barrier rib  16  may be in a subtractive color mixture relation, and more specifically in a complementary color relation. In color science, two colors are complementary if, when mixed, they produce a shade of grey. For example, dielectric layer  13  may be colored with a blue based color and barrier rib  16  may be colored with a red or brown based color. In this case, a bright room contrast can be improved as compared with the case where dielectric layer  16  is transparent, and barrier rib  16  is white. 
         [0049]    Barrier rib  16  is formed so that red, green, and blue discharge cells  17 R,  17 G, and  17 B are arranged in a triangular shape. Exhaust paths  18  may be formed between neighboring discharge cells among red, green, and blue discharge cells  17 R,  17 G, or  17 B. Therefore, during the process of manufacturing the plasma display channel and before rear and front substrates  10  and  20  are sealed, at least one external vacuum system (not shown) is connected with exhaust paths  18  to create a vacuum by exhausting the space between rear and front substrates  10  and  20  and the exhaust gas is conducted through exhaust paths  18 . After this exhausting process, rear and front substrates  10  and  20  is sealed and exhaust paths  18  are sealed shut along the periphery of the plasma display panel. 
         [0050]    Referring to  FIG. 3 , the discharge cells can be integrated with a high density on rear substrate  10  by arranging red, green, and blue discharge cells  17 R,  17 G, and  17 B which are the sub pixels into a triangular shape, as compared with a structure (not shown) in which the red, green, and blue discharge cells are repeatedly arranged along one direction within the same area. Here, the triangular arrangement structure represents a structure in which the respective centers of red, green, and blue discharge cells  17 R,  17 G, and  17 B form a triangle. 
         [0051]    Accordingly, barrier rib  16  defines each of red, green, and blue discharge cells  17 R,  17 G, and  17 B in a rhombic shape. Specifically, each of red, green, and blue discharge cells  17 R,  17 G, and  17 B has two vertices aligned in the y-axis direction and two vertices aligned in the x-axis direction. In addition, discharge cells  17 R,  17 G, and  17 B defined by barrier rib  16  are separate and independent along the y-axis direction and the x-axis direction. In other words, discharge cells  17 R,  17 G, and  17 B defined by barrier rib  16  are spaced apart from each other along both the y-axis direction and the x-axis direction such that exhaust paths can be formed between either two of the discharge cells selected from discharge cells  17 R,  17 G, and  17 B. 
         [0052]    Red, green, and blue discharge cells  17 R,  17 G, and  17 B having a rhombic shape are separately arranged in a triangular shape. Accordingly, exhaust paths  18 , which are formed between neighboring charge cells among red, green, and blue discharge cells  17 R,  17 G, or  17 B, are formed in third and fourth directions D 3  and D 4  that are rotated by a certain angle with respect to the y-axis and x-axis directions. Third direction D 3  is a direction located between (−)x and y directions and between (−)y and x directions. Fourth direction D 4  is a direction located between x and y directions and between (−)y and (−)x directions. 
         [0053]    Exhaust paths  18  are formed in third and fourth directions D 3  and D 4 , and discharge cells  17  are disposed between exhaust paths  18 . Therefore, impurities, which are remained in the plasma display panel when the plasma display panel is exhausted and sealed, can be minimized to improve the exhaust characteristic. 
         [0054]    For example, barrier ribs  16  defining the discharge cells have a certain width W 16 . Exhaust paths  18  have a width W 18  larger than that W 16  of barrier ribs  16 . In order to improve the exhaust characteristic, exhaust paths  18  may have a width as large as possible within an allowable range in which discharge cells  17  can be integrated. 
         [0055]    As described above, when the first and second directions are the y-axis and x-axis directions which are orthogonal to each other, third and fourth directions D 3  and D 4  are orthogonal to each other. At this time, the shape of discharge cells  17  may be a square. The first and second directions are not limited to the y-axis and x-axis directions. When the shape of discharge cells  17  is not the square, the third and fourth directions cross each other by an angle that is not a right angle. 
         [0056]    More specifically, barrier ribs  16  includes a pair of first barrier ribs  16   a,  which extend in third direction D 3 , and a pair of second barrier ribs  16   b,  which extend in fourth direction D 4 . 
         [0057]    The pair of first barrier ribs  16   a  extend in third direction D 3 . The pair of first barrier ribs  16   a  are spaced apart from each other by a distance corresponding to the length of a single discharge cell  17  along fourth direction D 4 . The pair of second barrier ribs  16   b  extend in fourth direction D 4 . The pair of second barrier ribs  16   b  are spaced apart from each other by a distance corresponding to the length of a single discharge cell  17  along third direction D 3 . 
         [0058]    The pair of first barrier ribs  16   a  and the pair of second barrier ribs  16   b  define a separate and single discharge cell  17 . Accordingly, the number of the pair first barrier ribs  16   a  corresponds to the number of discharge cells  17 . In addition, the number of the pair of second barrier ribs  16   b  corresponds to the number of discharge cells  17 . 
         [0059]    Accordingly, the pair of first barrier ribs  16   a  and the pair of second barrier ribs  16   b  define a single discharge cell  17  in a rhombic shape. Discharge cells  17  are separately and independently arranged in the x-axis and y-axis directions. 
         [0060]    On the other hand, in each discharge cell  17 , a ratio of a diagonal length Ly in the y-axis direction to a diagonal length Lx in the x-axis direction may range from approximately 1 to approximately 1.5. 
         [0061]    When the ratio (Ly/Lx) of diagonal length Ly in the y-axis direction to diagonal length Lx in the x-axis direction of discharge cell  17  is less than 1, diagonal length Lx in the x-axis direction is excessively greater than diagonal length Ly in the y-axis direction. Accordingly, it is difficult to obtain a suitable resolution in the x-axis direction. 
         [0062]    In addition, when the ratio (Ly/Lx) of diagonal length Ly in the y-axis direction to diagonal length Lx in the x-axis direction of discharge cell  17  is greater than 1.5, diagonal length Lx in the x-axis direction is excessively less than diagonal length Ly in the y-axis direction. Accordingly, since a space in discharge cell  17  is excessively reduced, it is difficult to obtain a suitable luminance. 
         [0063]    In addition, side surfaces  15  of barrier ribs  16  and inner surface  14  of dielectric layer  13  within discharge cell  17 , are coated with a florescent paste, which is dried, exposed to light, developed, and annealed to form phosphor layers  19 . 
         [0064]    Alternatively, phosphor layers  19  may be formed by selectively applying a photosensitive paste method using the aforementioned photosensitive paste, a pattern printing method using a phosphor paste, and a dry film method using a phosphor sheet. 
         [0065]    Phosphor layers  19  are made from the same color phosphor material in discharge cells  17  which are arranged along the y-axis direction. In addition, phosphor layers  19  are repeatedly made from red, green, and blue phosphor materials in the discharge cells which are disposed along the x-axis direction. 
         [0066]    On the other hand, sustain and scan electrodes  31  and  32  which are disposed on inner surface  22  of front substrate  20  have a surface discharge structure corresponding to each discharge cell  17  so as to generate gas discharge in discharge cells  17 . Sustain and scan electrodes  31  and  32  extend in the x-axis direction that crosses address electrodes  11 . 
         [0067]    For example, sustain electrodes  31  include transparent electrodes  31   a  and bus electrodes  31   b  which apply a voltage signal to transparent electrodes  31   a.  Scan electrodes  32  include transparent electrodes  32   a  and bus electrodes  32   b  which apply a voltage signal to transparent electrodes  32   a.  Transparent electrodes  31   a  and  32   a  are made from a transparent material (for example, indium tin oxide (ITO)) so as to maintain an aperture ratio of discharge cells  17  with respect to the portions where a surface discharge is carried out in discharge cells  17 . Bus electrodes  31   b  and  32   b  are made from a metal having high electrical conductivity so as to compensate for high electric resistance of transparent electrodes  31   a  and  32   a.    
         [0068]    Transparent electrodes  31   a  and  32   a  have widths W 31  and W 32  along the direction from the outside of discharge cell  17  toward the center of discharge cell  17  to form a surface discharge structure. A discharge gap G is formed at the center of discharge cell  17 . Bus electrodes  31   b  and  32   b  are disposed on transparent electrodes  31   a  and  32   a.  Bus electrodes  31   b  and  32   b  extend in the x-axis direction and are disposed at outer sides of discharge cells  17 . Accordingly, when the voltage signal is applied to bus electrodes  31   b  and  32   b,  the voltage signal is transferred to transparent electrodes  31   a  and  32   a  electrically connected to bus electrodes  31   b  and  32   b.    
         [0069]    Returning to  FIG. 1 , sustain and scan electrodes  31  and  32 , that cross address electrodes  11  and correspond to discharge cells  17 , are covered with a dielectric layer  41 . Dielectric layer  41  protects sustain and scan electrodes  31  and  32  against gas discharge. The wall charges are generated and accumulated in the dielectric layer when the discharge is carried out. 
         [0070]    On the other hand, dielectric layer  41  is covered with a passivation layer  42 . For example, passivation layer  42  is made from transparent magnesium oxide (MgO) which protects dielectric layer  40  to increase a secondary electron emission coefficient when the discharge is carried out. 
         [0071]    When the plasma display panel according to an embodiment of the present invention is driven, a reset discharge is carried out by a reset pulse applied to scan electrodes  32  during a reset period, an address discharge is carried out by a scan pulse applied to scan electrodes  32  and an address pulse applied to address electrodes  11  during an address period subsequent to the reset period, and then a sustain discharge is carried out by a sustain pulse applied to sustain and scan electrodes  31  and  32  during a sustain period. 
         [0072]    Sustain and scan electrodes  31  and  32  have a function of applying the sustain pulse for the sustain discharge. Scan electrodes  32  have a function of applying the reset pulse and the scan pulse. Address electrodes  11  have a function of applying the address pulse. Since the functions of sustain, scan, and address electrodes  31 ,  32 , and  11  may be changed according to voltage waveforms applied to sustain, scan, and address electrodes  31 ,  32 , and  11 , the functions of sustain, scan, and address electrodes  31 ,  32 , and  11  are not limited to the aforementioned functions. 
         [0073]    The plasma display panel according to an embodiment of the principles of the present invention selects discharge cells  17  to turn on by using the address discharge due to the interactions between address and scan electrodes  11  and  32  and drives the selected discharge cells  17  by using the sustain discharge due to the interactions between sustain and scan electrodes  31  and  32  to display images. 
         [0074]      FIG. 4  is a top plan view illustrating an arrangement of barrier ribs and discharge cells according to a second embodiment of the principles of the present invention. 
         [0075]    Since the arrangement structure of the barrier ribs and the discharge cells according to the second embodiment of the present invention is similar to that of  FIG. 3  according to the first embodiment of the present invention, the arrangement structure according to the second embodiment will be described in comparison with the arrangement structure according to the first embodiment. 
         [0076]    Barrier ribs  16  of the plasma display panel according to the first embodiment of the present invention define separate discharge cells  17  in x-axis and y-axis directions. Exhaust paths  18  are formed in third and fourth directions D 3  and D 4  so as to improve exhaust performance. 
         [0077]    On the other hand, barrier ribs  116  of the plasma display panel according to the second embodiment of the present invention form exhaust paths  118  by defining discharge cells  117  so that the discharge cells disposed along the x-axis direction are not spaced apart from one another and the discharge cells disposed along the y-axis direction are spaced apart from one another. For example, discharge cells  117  and  119  are not spaced apart from each other since the barrier ribs of discharge cells  117  and  119  are connected. On the other hand, discharge cells  115  and  119  are spaced apart from each other since there is a gap between the barrier ribs of each of the discharge cells. 
         [0078]    According to the second embodiment of the present invention, since exhaust paths  118  are connected along the x-axis direction and are not connected along the y-axis direction, it is possible to improve a degree of integration of discharge cells  117  in the x-axis direction. 
         [0079]    More specifically, barrier ribs  116  include a pair of first barrier ribs  116   a  and a pair of second barrier ribs  116   b.  The pair of first barrier ribs  116   a  and the pair of second barrier ribs  116   b  defines a single discharge cell  117  in a rhombic shape. Discharge cells  117  that are disposed along the x-axis direction are not spaced apart from one another. In other words, discharge cells  117  are not spaced apart from one another along the x-axis direction such that there is no exhaust path formed between discharge cells  17  disposed along the x-axis direction. Discharge cells  117  that are disposed along the y-axis direction are spaced apart from one another in the y-axis direction. Therefore, exhaust paths  118  are formed in the x-axis direction. 
         [0080]    Exhaust paths  118  which are formed in the x-axis direction have a zigzag shape alternately along third and fourth directions D 3  and D 4 . 
         [0081]      FIG. 5  is a top plan view illustrating an arrangement of barrier ribs and discharge cells according to a third embodiment of the principles of the present invention. 
         [0082]    Since an arrangement structure of barrier ribs and discharge cells of the plasma display panel according to the third embodiment of the present invention is similar to that of  FIG. 3  according to the first embodiment of the present invention, the arrangement structure according to the third embodiment will be described in comparison with the arrangement structure according to the first embodiment. 
         [0083]    Barrier ribs  16  of the plasma display panel according to the first embodiment of the present invention define separate discharge cells  17  in x-axis and y-axis directions. Exhaust paths  18  are formed in third and fourth directions D 3  and D 4  so as to improve exhaust performance. 
         [0084]    On the other hand, barrier ribs  216  of the plasma display panel according to the third embodiment of the present invention form exhaust paths  218  by defining discharge cells  217  so that the discharge cells that are disposed along the y-axis direction are not spaced apart from one another, and the discharge cells that are disposed along the x-axis direction are spaced apart from one another. 
         [0085]    According to the third embodiment of the present invention, since exhaust paths  218  are connected along the y-axis direction and are not connected along the x-axis direction, it is possible to improve a degree of integration of discharge cells  217  in the y-axis direction. 
         [0086]    More specifically, barrier ribs  216  include a pair of first barrier ribs  216   a  and a pair of second barrier ribs  216   b.  The pair of first barrier ribs  216   a  and the pair of second barrier ribs  216   b  defines a single discharge cell  217  in a rhombic shape. Discharge cells  217  that are disposed along the y-axis direction are not spaced apart from one another. In other words, there is no space between discharge cells  217  disposed along the y-axis direction. Discharge cells  217  that are disposed along the x-axis direction are spaced apart from one another in the x-axis direction. Therefore, exhaust paths  218  are formed in the y-axis direction. 
         [0087]    Exhaust paths  218  which are formed in the y-axis direction have a zigzag shape alternately along third and fourth directions D 3  and D 4 . 
         [0088]    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.