Abstract:
Disclosed is a plasma display panel, more particularly, a plasma display panel comprising scanning bus electrodes and sustaining bus electrodes formed on top of RGB cells. The plasma display panel comprises a first discharge cell provided with a first phosphor among a plurality of phosphors, a second discharge cell provided with a second phosphor among the plurality of phosphors, a first sustaining electrode pair formed on the first discharge cell and having a first area, and a second sustaining electrode pair formed on the second discharge cell and having a second area smaller than the first area. The color temperature of an image displayed by a plasma display panel can be set to appropriate level by enlarging the area of electrodes in the regions of a discharge cell provided with a specific phosphor.

Description:
[0001]     This Nonprovisional application claims priority under 35 U.S.C. § 119(a) on Patent Application No. 10-2004-0080640 filed in Korea on Oct. 8, 2004, the entire contents of which are hereby incorporated by reference.  
       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 comprising scanning bus electrodes and sustaining bus electrodes formed on R, G and B cells.  
         [0004]     2. Background of the Related Art  
         [0005]     In a conventional plasma display panel, a barrier rib formed between front and rear substrates made of soda-lime glass constitutes one unit cells, Each cell is filled with an inert gas such as helium-xenon(He—Xe), helium-neon(He—Ne), etc., If the inert gas is discharged with a high frequency voltage, vacuum ultraviolet rays are generated. Phosphor formed between the barrier ribs emits light corresponding to images.  
         [0006]      FIG. 1  is a perspective view schematically showing the structure of a conventional plasma display panel. As shown in  FIG. 1 , the plasma display panel comprises a front glass substrate  10  and a rear glass substrate  20 . The front glass substrate  10  and the rear glass substrate  20  are coupled in parallel to each other with a predetermined distance therebetween.  
         [0007]     A sustaining electrode pair  11  and  12  for sustaining the light emission of a discharge cell is formed on the front glass substrate  10 . The sustaining electrode pair  11  and  12  consists of a scan electrode  11  and sustain electrode  12 . The scan electrode  11  is supplied with a scan pulse for scanning and a sustain pulse for sustaining discharging. The sustain electrode  12  is applied with a sustain pulse alternated with a sustain pulse applied to the scan electrode  11 . The scan electrode  11  and the sustain electrode  12  are composed of transparent electrodes  11   a  and  12   a  made of transparent ITO material and bus electrodes  11   b  and  12   b  made of metal, respectively. The sustaining electrode pair  11  and  12  are covered with a dielectric layer  13   a . A protective layer  14  made of MgO is formed on the upper surface of the dielectric layer  13   a  so as to facilitate discharging more easily.  
         [0008]     A plurality of address electrodes  22  are arranged on the rear glass substrate  20  alternatively with the sustaining electrode pair  11  and  12 . A dielectric layer  13   b  is formed on the address electrodes  22 . Barrier ribs  21  for forming discharge cells are formed on the dielectric layer  13   b . A phosphor  23  for emitting visible light is coated between the barrier ribs  21 .  
         [0009]      FIG. 2  shows an electrode structure of the conventional plasma display panel. As shown in  FIG. 2 , the bus electrodes  11   a  and  11   b  are formed at upper and lower parts of a discharge cell  30  coated with R(red) phosphor, a discharge cell  40  coated with G(green) phosphor and a discharge cell  50  coated with B(blue) phosphor. The transparent electrodes  12   a  and  12   b  are formed in such a manner to be projected from the bus electrodes  11   a  and  11   b  toward the center of the discharge cell  30  coated with R(red) phosphor, of the discharge cell  40  coated with G(green) phosphor, and of the discharge cell  50  coated with B(blue) phosphor.  
         [0010]     The bus electrodes  11   a  and  11   b  and transparent electrodes  12   a  and  12   b  formed on the regions of each discharge cell have the same area. As a result, when discharging occurs in each of the discharge cells, the amount of discharge is the same. Since the amount of discharge is the same in each discharge cell, the discharge efficiency in each discharge cell is significantly depending on the phosphor type. The emission efficiency of B phosphor is less than the emission efficiency of R phosphor or G phosphor. That is, the amount of light emitted from the B phosphor according to a specific amount of discharge is less than the amount of light emitted from the R phosphor or G phosphor. Therefore, if the area of the electrodes formed on each discharge cell is the same, the color temperature of an image displayed by the conventional plasma display panel is not being set to an appropriate level.  
       SUMMARY OF THE INVENTION  
       [0011]     Accordingly, an object of the present invention is to solve at least the problems and disadvantages of the background art.  
         [0012]     The present invention provides a plasma display panel comprising electrodes with an enhanced structure for improvement of color temperature.  
         [0013]     The plasma display panel of the present invention comprises: a first discharge cell provided with a first phosphor among a plurality of phosphors; a second discharge cell provided with a second phosphor among the plurality of phosphors; a first sustaining electrode pair formed on the first discharge cell and having a first area; and a second sustaining electrode pair formed on the second discharge cell and having a second area smaller than the first area.  
         [0014]     The plasma display panel of the present invention comprises: a first discharge cell partitioned by barrier ribs and provided with a first phosphor among a plurality of phosphors; a second discharge cell partitioned by barrier ribs and provided with a second phosphor among the plurality of phosphors; a first transparent electrode portion projected on the first discharge cell toward the center of the first discharge cell and having a first partial area; and a second transparent electrode portion projected on the second discharge cell toward the center of the second discharge cell and having a second partial area smaller than the first partial area.  
         [0015]     In the present invention, the color temperature of an image displayed by a plasma display panel is set to the appropriate level by enlarging the area of electrodes in the regions of a discharge cell provided with a specific phosphor. 
     
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0016]     The invention will be described in detail with reference to the following drawings in which like numerals refer to like elements:  
         [0017]      FIG. 1  is a perspective view schematically showing a structure of a conventional plasma display panel;  
         [0018]      FIG. 2  shows an electrode structure of the conventional plasma display panel;  
         [0019]      FIG. 3  is a plane view of a plasma display panel according to a first embodiment of the present invention; and  
         [0020]      FIG. 4  is a plane view of a plasma display panel according to a second embodiment of the present invention. 
     
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS  
       [0021]     Preferred embodiments of the present invention will be described in a more detailed manner with reference to the drawings.  
         [0022]     The plasma display panel of the present invention comprises: a first discharge cell provided with a first phosphor among a plurality of phosphors; a second discharge cell provided with a second phosphor among the plurality of phosphors; a first sustaining electrode pair formed on the first discharge cell and having a first area; and a second sustaining electrode pair formed on the second discharge cell and having a second area smaller than the first area.  
         [0023]     The first phosphor is a blue phosphor.  
         [0024]     The first sustaining electrode pair comprises a first scanning bus electrode, the second sustaining electrode pair comprises a second scanning bus electrode, and the first scanning bus electrode is wider than the second scanning bus electrode.  
         [0025]     The first sustaining electrode pair comprises a first scanning bus electrode, the second sustaining electrode pair comprises a second scanning bus electrode, and the first scanning bus electrode is wider than the second scanning bus electrode.  
         [0026]     The plasma display panel of the present invention comprises: a first discharge cell partitioned by barrier ribs and provided with a first phosphor among a plurality of phosphors; a second discharge cell partitioned by barrier ribs and provided with a second phosphor among the plurality of phosphors; a first transparent electrode portion projected on the first discharge cell toward the center of the first discharge cell and having a first partial area; and a second transparent electrode portion projected on the second discharge cell toward the center of the second discharge cell and having a second partial area smaller than the first partial area.  
         [0027]     The first phosphor is a blue phosphor.  
         [0028]     The first transparent electrode portion comprises a first scanning vertical connecting portion formed toward the center of the first discharge cell, the second transparent electrode portion comprises a second scanning vertical connecting portion formed toward the center of the second discharge cell, and the first scan vertical connecting portion is wider than the second scanning vertical connecting portion.  
         [0029]     The first scanning vertical connecting portion is wider than the second scanning vertical connecting portion, and the width of the first scanning vertical connecting portion increases in the direction of the barrier ribs partitioning the first discharge cell.  
         [0030]     The first transparent electrode portion further comprises a first scanning horizontal connecting portion connecting to the first scanning vertical connecting portion, the second transparent electrode portion further comprises a second scanning horizontal connecting portion connecting to the second scanning vertical connecting portion, and the first scanning horizontal connecting portion is wider than the second scanning horizontal connecting portion.  
         [0031]     The first scanning horizontal connecting portion is wider than the second scanning horizontal connecting portion, and the width of the first scanning horizontal connecting portion increases in the direction of the barrier ribs partitioning the first discharge cell.  
         [0032]     The first transparent electrode portion comprises a first sustaining vertical connecting portion formed toward the center of the first discharge cell, the second transparent electrode portion comprises a second sustaining vertical connecting portion formed toward the center of the second discharge cell, and the first sustaining vertical connecting portion is wider than the second sustaining vertical connecting portion.  
         [0033]     The first sustaining vertical connecting portion is wider than the second sustaining vertical connecting portion, and the width of the first sustaining vertical connecting portion increases in the direction of the barrier ribs partitioning the first discharge cell.  
         [0034]     The first transparent electrode portion further comprises a first sustaining horizontal connecting portion connecting to the first sustaining vertical connecting portion, the second transparent electrode portion further comprises a second sustaining horizontal connecting portion connecting to the second sustaining vertical connecting portion, and the first sustaining horizontal connecting portion is wider than the second sustaining horizontal connecting portion.  
         [0035]     The first sustaining horizontal connecting portion is wider than the second sustaining horizontal connecting portion, and the width of the first sustaining horizontal connecting portion increases in the direction of the barrier ribs partitioning the first discharge cell.  
         [0036]     Hereinafter, specific embodiments of the present invention will be described with reference to the accompanying drawings.  
       Embodiment 1  
       [0037]      FIG. 3  is a plane view of a plasma display panel according to a first embodiment of the present invention. As shown in  FIG. 3 , the plasma display panel comprises a first discharge cell  300 , a second discharge cell  310 , a first sustaining electrode pair  320  and a second sustaining electrode pair  330 .  
         [0038]     The first discharge cell  300  is partitioned by barrier ribs and provided with a first phosphor among a plurality of phosphors. It is preferable that the plurality of phosphor comprises a R(red) phosphor, a G(green) phosphor and a B(blue) phosphor. Preferably, the first phosphor is a B phosphor.  
         [0039]     The second discharge cell  310  is partitioned by barrier ribs and provided with a second phosphor among a plurality of phosphors. Preferably, the first phosphor is a R(red) phosphor or a G(green) phosphor.  
         [0040]     The first sustaining electrode pair  320  is formed on a front glass substrate (not shown) on the first discharge cell  300  and has a first area. Such first sustaining electrode pair  320  comprise a first scanning bust electrode  3201 , a first sustaining bus electrode  3203 , a first scanning transparent electrode  3205  and a first sustaining transparent electrode  3207 . The position of the first scanning bus electrode  3201  and the first scanning transparent electrode  3205 , and the position of the first sustaining bus electrode  3203  and the first sustaining transparent electrode  3207  can alternate with each other. That is, the first scanning bus electrode  3201  and the first scanning transparent electrode  3205  can be positioned at a lower part of the first discharge cell  300 , and the first sustaining bus electrode  3203  and the first sustaining transparent electrode  3207  can be positioned at an upper part of the first discharge cell  300 .  
         [0041]     The second sustaining electrode pair  330  is formed on a front glass substrate (not shown) on the second discharge cell  310  and has a second area smaller than the first area. Such second sustaining electrode pair  330  comprises a second scanning bust electrode  3301 , a second sustaining bus electrode  3303 , a second scanning transparent electrode  3305  and a second sustaining transparent electrode  3307 . The position of the second scanning bus electrode  3301  and the second scanning transparent electrode  3305 , and the position of the second sustaining bus electrode  3303  and of the second sustaining transparent electrode  3307  can alternate with each other. That is, the second scanning bus electrode  3301  and the second scanning transparent electrode  3305  can be positioned at a lower part of the second discharge cell  310 , and the second sustaining bus electrode  3303  and the second sustaining transparent electrode  3307  can be positioned at an upper part of the second discharge cell  310 .  
         [0042]     As shown in  FIG. 3 , the first scanning bus electrode  3201  and first sustaining bus electrode  3203  of the first sustaining electrode pair  320  is wider than the second scanning bus electrode  3301  and second sustaining bus electrode  3303  of the second sustaining electrode pair  330 . As a result, as the first scanning bus electrode  3201  and the first sustaining bus electrode  3203  are formed on the first discharge cell  300  where the B phosphor is formed, and the second scanning bus electrode  3301  and the second sustaining bus electrode  3303  are formed on the second discharge cell  310  where the R phosphor or G phosphor is formed, the amount of discharge of the first discharge cell  300  becomes greater than the amount of discharge of the second discharge cell  310 . Therefore, because the first discharge cell in which the B phosphor having a smaller light emission efficiency is formed, emits a greater amount of light than an amount of light emitted by the second discharge cell, the color temperature of an image displayed by the plasma display panel can be set to the appropriate level.  
       Embodiment 2  
       [0043]      FIG. 4  is a plane view of a plasma display panel according to a first embodiment of the present invention. As shown in  FIG. 4 , the plasma display panel comprises a first discharge cell  400 , a second discharge cell  410 , a first sustaining electrode pair  420  and a second sustaining electrode pair  430 .  
         [0044]     The first discharge cell  400  is partitioned by barrier ribs and provided with a first phosphor among a plurality of phosphors. It is preferable that the plurality of phosphor comprises a R(red) phosphor, a G(green) phosphor and a B(blue) phosphor. Preferably, the first phosphor is a B phosphor.  
         [0045]     The second discharge cell  410  is partitioned by barrier ribs and provided with a second phosphor among a plurality of phosphors. Preferably, the first phosphor is a R(red) phosphor or G(green) phosphor.  
         [0046]     The first sustaining electrode pair  420  is formed on a front glass substrate (not shown) on the first discharge cell  400  and has a first area. Such first sustaining electrode pair  420  comprise a first scanning bust electrode  4201 , a first sustaining bus electrode  4203 , a first scanning transparent electrode  4205  and a first sustaining transparent electrode  4207 . The position of the first scanning bus electrode  4201  and the first scanning transparent electrode  4205 , and the position of the first sustaining bus electrode  4203  and of the first sustaining transparent electrode  4207  can alternate with each other. That is, the first scanning bus electrode  4201  and the first scanning transparent electrode  4205  can be positioned at a lower part of the first discharge cell  400 , and the first sustaining bus electrode  4203  and the first sustaining transparent electrode  4207  can be positioned at an upper part of the first discharge cell  400 . The first scanning transparent electrode  4205  and the first sustaining transparent electrode  4207  are projected from the first scanning bus electrode  4201  and the first sustaining bus electrode  4203 , respectively, toward the center of the first discharge cell  400 . The first scanning transparent electrode  4205  and the first sustaining transparent electrode  4207  have a first partial area. That is, the first partial area is the sum of the areas of the first scanning transparent electrode  4205  and first sustaining transparent electrode  4207 . The first scanning transparent electrode  4205  comprises a first scanning vertical connecting portion  4205 - 1  vertically connecting to the first scanning bus electrode  4201  and a first scanning horizontal connecting portion  4205 - 2  vertically connecting to the first scanning vertical connecting portion  4205 - 1 . The first sustaining transparent electrode  4207  comprises a first sustaining vertical connecting portion  4207 - 1  vertically connecting to the first sustaining bus electrode  4203  and a first sustaining horizontal connecting portion  4207 - 2  vertically connecting to the first sustaining vertical connecting portion  4207 - 1 .  
         [0047]     The second sustaining electrode pair  430  is formed on a front glass substrate (not shown) on the second discharge cell  410  and has a second area smaller than the first area. Such second sustaining electrode pair  430  comprises a second scanning bust electrode  4301 , a second sustaining bus electrode  4303 , a second scanning transparent electrode  4305  and a second sustaining transparent electrode  4307 . The position of the second scanning bus electrode  4301  and the second scanning transparent electrode  4305 , and the position of the second sustaining bus electrode  4303  and of the second sustaining transparent electrode  4307  can be alternate with each other. That is, the second scanning bus electrode  4301  and the second scanning transparent electrode  4305  can be positioned at a lower part of the second discharge cell  410 , and the second sustaining bus electrode  3303  and the second sustaining transparent electrode  4307  can be positioned at an upper part of the second discharge cell  410 . The second scanning transparent electrode  4305  and the second sustaining transparent electrode  4307  are projected from the second scanning bus electrode  4201  and the second sustaining bus electrode  4303 , respectively, toward the center of the second discharge cell  410 . The second scanning transparent electrode  4305  and the second sustaining transparent electrode  4307  have a second partial area. That is, the second partial area is the sum of the areas of the second scanning transparent electrode  4305  and second sustaining transparent electrode  4307 . The second scanning transparent electrode  4305  comprises a second scanning vertical connecting portion  4305 - 1  vertically connecting to the second scanning bus electrode  4301  and a second scanning horizontal connecting portion  4305 - 2  vertically connecting to the second scanning vertical connecting portion  4205 - 1 . The second sustaining transparent electrode  4307  comprises a second sustaining vertical connecting portion  4307 - 1  vertically connecting to the second sustaining bus electrode  4303  and a second sustaining horizontal connecting portion  4307 - 2  vertically connecting to the second sustaining vertical connecting portion  4307 - 1 .  
         [0048]     As shown in  FIG. 4 , the first partial area of the first scanning transparent electrode  4205  and the first sustaining transparent electrode  4207  is larger than the second area of the second scanning transparent electrode  4305  and second sustaining transparent electrode  4307 . As a result, as the first scanning transparent electrode  4205  and the first sustaining transparent electrode  4207  are formed on the first discharge cell  400  where the B phosphor is formed, and the second scanning transparent electrode  4305  and the second sustaining transparent electrode  4307  are formed on the second discharge cell  410  where the R phosphor or G phosphor is formed, the amount of discharge of the first discharge cell  400  becomes greater than the amount of discharge of the second discharge cell  410 . Therefore, because the B phosphor having a lower light emission efficiency emits a greater amount of light, the color temperature of an image displayed by the plasma display panel can be set to the appropriate level. The width w 1  of the first scanning vertical connecting portion  4205 - 1  of the first scanning transparent electrode  4205  can be wider than the width w 2  of the second scanning vertical connecting portion  4305 - 1  of the second scanning transparent electrode  4305 . The width w 3  of the first scanning horizontal connecting portion  4305 - 2  of the second scanning transparent electrode  4305  can be wider than the width w 4  of the second scanning horizontal connecting portion  4305 - 2  of the second scanning transparent electrode  4305 . Likewise, the width w 6  of the first sustaining vertical connecting portion  4207 - 1  of the first sustaining transparent electrode  4207  can be wider than the width w 5  of the second sustaining vertical connecting portion  4307 - 1  of the second sustaining transparent electrode  4307 . The width w 7  of the first sustaining horizontal connecting portion  4207 - 1  of the first sustaining transparent  4207  can be wider than the width w 8  of the second sustaining horizontal connecting portion  4307 - 2  of the second sustaining transparent electrode  4307 .  
         [0049]     If the width of the first scanning horizontal connecting portion  4205 - 2  and first sustaining horizontal connecting portion  4207 - 2  increases toward the center of the first discharge cell  400 , a discharge gap is reduced and thus a discharge firing voltage increases. As a result, it is preferable that the first scanning horizontal connecting portion  4205 - 2  and the first sustaining horizontal connecting portion  4207 - 2  have a width that increases toward the barrier ribs, respectively.  
         [0050]     The invention being thus described, it will be obvious that the same may be varied in many ways. Such variations are not to be regarded as a departure from the spirit and scope of the invention, and all such modifications as would be obvious to one skilled in the art area intended to be comprised within the scope of the following claims.