Abstract:
A plasma display panel includes a substrate, a plurality of first electrodes on the substrate, the first electrodes having a first length and being on a first plane, a plurality of second electrodes on the substrate, the second electrodes having a second length and being on a second plane, the second length being different than the first length, and the second plane being different than the first plane, and a plurality of dielectric layers on the substrate, the dielectric layers embedding the first and second electrodes.

Description:
CROSS-REFERENCE TO RELATED APPLICATION 
       [0001]    The present application is a related application of a co-pending U.S. patent application Ser. No. 12/071,975, entitled “Plasma Display Panel,” which was filed on Feb. 28, 2008, and is incorporated by reference herein in its entirety. 
     
    
     BACKGROUND OF THE INVENTION 
       [0002]    1. Field of the Invention 
         [0003]    Embodiments of the present invention relate to a plasma display panel (PDP). More particularly, embodiments of the present invention relate to a PDP having electrodes with different lengths on different planes. 
         [0004]    2. Description of the Related Art 
         [0005]    A PDP may refer to a flat panel display device displaying images via a gas discharge phenomenon. For example, the PDP may include a discharge gas between two substrates, so application of a voltage via a plurality of discharge electrodes to the discharge gas may generate a discharge. The discharge may trigger ultraviolet (UV) light to excite phosphor layers to emit visible light. 
         [0006]    The conventional discharge electrodes may include electrode terminals formed of silver to facilitate connection to a signal transmission unit. However, silver may be ionized by moisture in the atmosphere, and may trigger electron and/or material migration from one electrode to another. Such an electron migration may reduce distance between adjacent electrode terminals, thereby causing short-circuits therebetween and display defects, e.g., a vertical line defect in a displayed image. 
       SUMMARY OF THE INVENTION 
       [0007]    Embodiments of the present invention are therefore directed to a PDP, which substantially overcomes one or more of the disadvantages of the related art. 
         [0008]    It is therefore a feature of an embodiment of the present invention to provide a PDP having a structure capable of minimizing shorting between adjacent discharge electrodes. 
         [0009]    At least one of the above and other features and advantages of the present invention may be realized by providing a PDP, including a substrate, a plurality of first electrodes on the substrate, the first electrodes having a first length and being on a first plane, a plurality of second electrodes on the substrate, the second electrodes having a second length and being on a second plane, the second length being different than the first length, and the second plane being different than the first plane, and a plurality of dielectric layers on the substrate, the dielectric layers embedding the first and second electrodes. 
         [0010]    At least one dielectric layer of the plurality of dielectric layers may be between the plurality of first electrodes and the plurality of second electrodes. The plurality of dielectric layers may include first and second dielectric layers on the substrate, the first electrodes being embedded in the first dielectric layer, and the second electrodes being embedded in the second dielectric layer. The first electrodes may be between the substrate and the first dielectric layer, and the second electrodes may be between the first dielectric layer and the second dielectric layer. The first and second electrodes may have an alternating array pattern. The first electrodes may define odd-numbered electrodes on the substrate, and the second electrodes may define even-numbered electrodes on the substrate. The first electrodes may be longer than the second electrodes. The first dielectric layer may be wider than the second dielectric layer. The first and second electrodes may be address electrodes. The first and second electrodes may be sustain discharge electrodes. 
         [0011]    The PDP may further include a signal transmitter, the signal transmitter having lead terminals electrically connected to the first and second electrodes. The lead terminals may be positioned to correspond to terminals of the first and second electrodes. The signal transmitter may include leads embedded in a flexible film, terminals of the leads being exposed externally to correspond to the terminals of the first and second electrodes. The terminals of the leads may include first lead terminals connected to terminals of the first electrodes and second lead terminals connected to terminals of the second electrodes. The first and second lead terminals may be arranged at different distances from an edge of the flexible film. The second lead terminals may be closer to the edge of the flexible film than the first lead terminals. 
         [0012]    At least one of the above and other features and advantages of the present invention may be also realized by providing a PDP, including first and second substrates facing one another, a plurality of first and second discharge electrodes on the first substrate, a plurality of first address electrodes on the second substrate, the first address electrodes having a first length and being on a first plane, a plurality of second address electrodes on the second substrate, the second address electrodes having a second length and being on a second plane, the second length being different than the first length, and the second plane being different than the first plane, a plurality of dielectric layers on the substrate, the dielectric layers embedding the first and second electrodes, and a signal transmitter electrically connected to the first and second address electrodes. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0013]    The above and other features and advantages of the present invention will become more apparent to those of ordinary skill in the art by describing in detail exemplary embodiments thereof with reference to the attached drawings, in which: 
           [0014]      FIG. 1  illustrates a partial perspective view of a PDP according to an embodiment of the present invention; 
           [0015]      FIG. 2  illustrates a plan view of a connection of the PDP of  FIG. 1  to a driving circuit board through a signal transmitter; 
           [0016]      FIG. 3  illustrates a plan view of a connection of electrode terminals to a signal transmitter according to an embodiment of the present invention; and 
           [0017]      FIG. 4  illustrates a perspective view of  FIG. 3 . 
       
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
       [0018]    Korean Patent Application No. 10-2007-0069354, filed on Jul. 10, 2007, in the Korean Intellectual Property Office, and entitled: “PDP Having Discharge Electrodes Having Different Lengths,” is incorporated by reference herein in its entirety. 
         [0019]    Exemplary embodiments of the present invention will now be described more fully hereinafter with reference to the accompanying drawings, in which exemplary embodiments of the invention are illustrated. Aspects of the invention may, however, be embodied in different forms and should not be construed as limited to the embodiments set forth herein. Rather, these embodiments are provided so that this disclosure will be thorough and complete, and will fully convey the scope of the invention to those skilled in the art. 
         [0020]    In the figures, the dimensions of layers and regions may be exaggerated for clarity of illustration. It will also be understood that when a layer or element is referred to as being “on” another layer or substrate, it can be directly on the other layer or substrate, or intervening layers or elements may also be present. Further, it will be understood that the term “on” can indicate solely a vertical arrangement of one element or layer with respect to another element or layer, and may not indicate a specific vertical orientation. In addition, it will also be understood that when a layer is referred to as being “between” two layers, it can be the only layer between the two layers, or one or more intervening layers may also be present. Like reference numerals refer to like elements throughout. 
         [0021]      FIG. 1  illustrates a partial perspective view of a PDP, e.g., a 3-electrode surface discharge type PDP, according to an exemplary embodiment of the present invention. Referring to  FIG. 1 , a PDP  200  may include a first substrate  201  and a second substrate  202  disposed parallel to the first substrate  201 . Each one of the first and second substrates  201  and  202  may be any one of a transparent substrate, e.g., formed of soda lime glass, a semi-permeable substrate, a reflective substrate, or a colored substrate. A frit glass layer  303 , as illustrated in  FIG. 2 , may be applied to peripheral areas of inner surfaces of the first and second substrates  201  and  202  to connect therebetween in order to form a sealed space between the first and second substrates  201  and  202 . The sealed space, i.e., a display area  301  illustrated in  FIG. 2 , may include functional elements, e.g., sustain discharge electrodes  203  and discharge cells, and may provide display functions. In this respect, it should be noted that “inner surfaces” may refer to surfaces facing the sealed space. 
         [0022]    The sustain discharge electrodes  203  of the PDP  200  may be in the display area  301 , i.e., on an inner surface of the first substrate  201 . As illustrated in  FIG. 1 , each pair of sustain discharge electrodes  203  may include an X electrode  204  and a Y electrode  205 , so a pair of the X electrode  204  and the Y electrode  205  may be disposed along an array of discharge cells along the x-axis. Each X electrode  204  may include a first bus electrode line  207  along the x-axis and a plurality of transparent electrodes  206  electrically connected to the first bus electrode line  207 . Each transparent electrode  206  may be independently disposed in each discharge cell in the array of discharge cells corresponding to the first bus electrode line  207 . Each Y electrode  205  may include a plurality of second transparent electrodes  208  independently disposed in each discharge cell and electrically connected to a second bus electrode line  209 . The second bus electrode line  209  may be parallel to the first bus electrode line  207 . 
         [0023]    The first bus electrode line  207  and the second bus electrode line  209  may be positioned along edges of facing sides of the discharge cells, and may have an alternating stripe pattern. Accordingly, a pair of first and second transparent electrodes  206  and  208  may be positioned in each discharge cell along the first and second bus electrode lines  207  and  209 , such that the first and second transparent electrodes  206  and  208  may be spaced apart from each other at a predetermined interval. The predetermined interval may correspond to a center of each discharge cell in order to form a discharge gap. 
         [0024]    A cross section of each of the first transparent electrodes  206  and the second transparent electrodes  208  may have any suitable shape, e.g., a quadrangle. The first transparent electrodes  206  and the second transparent electrodes  208  may be formed of a transparent material, e.g., an indium-tin-oxide (ITO) film, and the first bus electrode lines  207  and the second bus electrode lines  209  may be formed of a metal having excellent conductivity, e.g., a silver paste, chrome-copper-chrome layer, and so forth. 
         [0025]    The X electrode  204  and the Y electrode  205  may be embedded in a first dielectric layer  210 . The first dielectric layer  210  may be formed using a transparent dielectric substance having high dielectric properties, e.g., PbO—B 2 O 3 —SiO 2 . A protective layer  211  may be formed, e.g., of magnesium oxide (MgO), on the first dielectric layer  210  in order to increase secondary electron emission. 
         [0026]    The PDP  200  may further include address electrodes  212  on an inner surface, i.e., a surface facing the discharge cells, of the second substrate  202 . The address electrodes  212 , as illustrated in  FIG. 1 , may extend along respective arrays of discharge cells along the y-axis, i.e., each address electrode  212  may extend along a single array of discharge cells. The address electrodes  212  may cross the discharge electrodes  203 , and may have a stripe pattern. The address electrodes  212  may include a plurality of first address electrodes  212   a  and a plurality of second address electrodes  212   b  performing address discharge, as illustrated in  FIGS. 3-4 . The first and second address electrodes  212   a  and  212   b  may have different lengths, and may be positioned on different planes, as will be discussed in more detail below with reference to  FIGS. 3-4 . A second dielectric layer  213  may be formed on the second substrate  202  of a material having high dielectric properties, e.g., may be substantially similar to the first dielectric layer  210 , and may include at least a first dielectric portion  213   a  and a second dielectric portion  213   b , as will be discussed in more detail below with reference to  FIGS. 3-4 . 
         [0027]    The PDP  200  may further include barrier ribs  214 , as illustrated in  FIG. 1 , between the first and second substrates  201  and  202 . The barrier ribs  214  may define the discharge cells, and may prevent cross talk between adjacent discharge cells. The barrier ribs  214  may include first barrier ribs  215  along the x-axis and second barrier ribs  216  along the y-axis. The barrier ribs  214  may define the discharge cells to have a lattice pattern and any suitable cross-section, e.g., a polygon, a quadrangle, a circle, an oval, and so froth. Discharge gas, e.g., neon (Ne), xenon (Xe), helium (He), or a combination thereof, may be injected into the discharge cells. 
         [0028]    The PDP  200  may further include phosphor layers  217  to emit visible light when excited by UV light generated by the discharge gas. The phosphor layers  217  may be formed inside the discharge cells, e.g., may be coated on any area of the discharge cells. For example, the phosphor layers  217  may be formed on an inner surface of the second dielectric layer  213  and/or on sidewalls of the barrier ribs  214 . The phosphor layers  217  may include red phosphor, e.g., (Y,Gd)BO 3 ; Eu +3 , green phosphor, e.g., Zn 2 SiO 4 :Mn 2+ , and/or blue phosphor, e.g., BaMgAl 10 O 17 :Eu 2+ . 
         [0029]    As illustrated in  FIG. 2 , the first substrate  201  may be shorter than the second substrate  202 , e.g., along the y-axis. Accordingly, the display area  301  may include only an area formed by an overlap of the first and second substrates  201  and  202 . Portions of the second substrate  202  extending, e.g., along the y-axis, beyond the first substrate  201  may be referred to as a non-display area  302 , and may include electrode terminals  304  of the discharge electrodes  203  or of the address electrodes  212 . The non-display area  302  may be a peripheral area in communication with at least one edge of the display area  301  to expose the electrode terminals  304 , thereby facilitating electrical connection thereof to a driving circuit board  309  via a signal transmitter  305 , as illustrated in  FIG. 2 . The PDP  100  may include a plurality of non-display areas  302 , i.e., the second substrate  202  may extend beyond more than a single edge of the first substrate  201 . 
         [0030]    The electrode terminals  304  may extend on an upper surface of the second substrate  202  along the y-axis, and may be arranged in a stripe-pattern along the x-axis in the non-display area  302 , as illustrated in  FIG. 2 . The electrode terminals  304  may have a structure of group units. In other words, the electrode terminals  304  may be arranged into a plurality of group units spaced apart from each other, each group unit having a plurality of electrode terminals  304 , as illustrated in  FIG. 2 . A single group unit of electrode terminals  304  may be separately connected to a single signal transmitter  305 . Accordingly, a large size of the PDP  200  may require a plurality of signal transmitters  305  connected to a plurality of electrode terminals  304  arranged into a plurality of group units. The electrode terminals  304  may not be covered by the second dielectric layer  213  and/or by the first dielectric layer  210  to facilitate electrical connection between the electrode terminals  304  and the signal transmitters  305 . The electrode terminals  304  may be disposed on different planes, as will be discussed in more detail below with reference to  FIG. 3 . 
         [0031]    The signal transmitter  305  of the PDP  200  may be formed in any suitable shape, and may be connected to the electrode terminals  304 , as illustrated in  FIG. 2 , to drive the PDP  200 . More specifically, the signal transmitter  305  may be connected between the electrode terminals  304  and the driving circuit unit  309  to transmit electric signals therebetween. The signal transmitter  305  may include a plurality of driving integrated circuits (ICs)  306 , a plurality of leads  307  patterned to be connected to the driving ICs  306 , and a flexible film  308  covering the leads  307 . The leads  307  may be disposed on portions to correspond to the electrode terminals  304  in order to be electrically connected thereto, i.e., form an electrical connection between the signal transmitter  305  and the electrode terminals  304 . The leads  307  may be electrically connected to the electrode terminals  304  via first lead terminals  307   a , i.e., terminals formed at a first edge of the flexible film  308 . A connector  310  may form an electrical connection between the signal transmitter  305  and the driving circuit unit  309  via second lead terminals  307   b , i.e., terminals formed at a second edge of the flexible film  308  opposite the first edge. 
         [0032]    The connection between the electrode terminals  304  and the signal transmitters  305  will be described in more detail below with reference to  FIGS. 3-4 .  FIG. 3  illustrates an enlarged plan view of the first and second address electrodes  212   a  and  212   b  and the signal transmitter  305 , and  FIG. 4  illustrates a perspective view of  FIG. 3 . It is noted that even though first and second address electrodes  212   a  and  212   b  are illustrated in  FIGS. 3-4  as having different lengths and being positioned on different planes, other electrodes, e.g., sustain discharge electrodes  203  performing sustain discharge and/or any other electrodes of a PDP, may be configured in a substantially same arrangement. 
         [0033]    Referring to  FIGS. 3-4 , the first and second address electrodes  212   a  and  212   b  may be embedded in a plurality of first and second dielectric portions  213   a  and  213   b  on the second substrate  202 . The plurality of first and second address electrodes  212   a  and  212   b  may be on first and second planes, respectively, to form a multi-layered structure of first and second address electrodes  212   a  and  212   b  separated by first and second dielectric portions  213   a  and  213   b . The first and second planes may both be horizontal planes, i.e., in the xy-plane, but the first and second planes may have different vertical positions along the z-axis. Accordingly, the first address electrodes  212   a  may have a different vertical position along the z-axis, as compared to the second address electrodes  212   b.    
         [0034]    More specifically, the first address electrodes  212   a  may extend along the y-axis on the second substrate  202 , and may have a stripe pattern along the x-axis, as illustrated in  FIG. 3 . The first address electrodes  212   a  may have a first interval d 1  therebetween, as measured along the x-axis. A predetermined length of the first address electrodes  212   a  may be embedded in the first dielectric portion  213   a , so first electrode terminals  304   a  of the first address electrodes  212   a  may be exposed, i.e., not embedded in the first dielectric portion  213   a . The second address electrodes  212   b  may extend along the y-axis on the first dielectric portion  213   a , and may have a stripe pattern along the x-axis, as further illustrated in  FIG. 3 . The second address electrodes  212   b  may have a second interval d 2  therebetween, as measured along the x-axis. A predetermined length of the second address electrodes  212   b  may be embedded in the second dielectric portion  213   b , so second electrode terminals  304   b  of the second address electrodes  212   b  may be exposed, i.e., not embedded in the second dielectric portion  213   b.    
         [0035]    The first address electrodes  212   a  may be disposed between the second substrate  202  and the first dielectric portion  213   a , e.g., may be embedded within the first dielectric portion  213   a . Accordingly, the first electrode terminals  304   a  may be exposed on the second substrate  202 , and may have the first intervals d 1  therebetween. The second discharge electrodes  212   b  may be disposed between the first dielectric portion  213   a  and the second dielectric portion  213   b , e.g., may be embedded within the second dielectric portion  213   b . Accordingly, the second electrode terminals  304   b  may be exposed on the first dielectric portion  213   a , and may have the second intervals d 2  therebetween. 
         [0036]    The second address electrodes  212   b  may be disposed between the first address electrodes  212   a  to form an alternating array of multi-layered first and second address electrodes  212   a  and  212   b . For example, the first address electrodes  212   a  may be disposed in odd columns on the first planes and the second address electrodes  212   b  may be disposed in even columns on the second plane. As such, the first and second electrode terminals  304   a  and  340   b  may form an alternating array of multi-layered first and second electrode terminals  304   a  and  340   b , so a distance between two adjacent first and second electrode terminals  304   a  and  304   b  may be diagonal, i.e., may have both vertical and horizontal components. The horizontal component of the diagonal distance may equal about half the first or second intervals d 1  and d 2 . 
         [0037]    The first and second address electrodes  212   a  and  212   b  may have different lengths. More specifically, the first address electrodes  212   a  may be longer that the second address electrodes  212   b  along the y-axis. Further, the first dielectric layer  213   a  may be wider than the second dielectric layer  213   b  along the y-axis in order to form areas in which the first and second electrode terminals  304   a  and  304   b  may be exposed externally. Accordingly, the first electrode terminals  304   a  may be disposed closer to an edge of the second substrate  202 , as compared to the second electrode terminals  304   b . As such, the signal transmitter  305  may be electrically connected to the first address electrodes  212   a  and the second address electrodes  212   b  at the interval d 1  between the first address electrodes  212   a  disposed in odd columns or the interval d 2  between the second address electrodes  212   b  disposed in even columns. Therefore, the first lead terminals  307   a  of the signal transmitter  305  may be arranged at a configuration corresponding to the first and second electrode terminals  304   a  and  304   b.    
         [0038]    More specifically, as illustrated in  FIG. 3 , the first lead terminals  307   a  may be exposed externally on an edge of the flexible film  308  to facilitate electrical connection to the first and second electrode terminals  304   a  and  304   b  of the first and second address electrodes  212   a  and  212   b , respectively. The leads  307  (not shown) may be embedded in the flexible film  308 . The first lead terminals  307   a  may be formed on a same plane or not, and may be arranged at different locations of the flexible film  308  to correspond to the first and second terminals  304   a  and  304   b . In other words, the first lead terminals  307   a  may include first terminals  455  electrically connected to the first electrode terminals  304   a  of the first address electrodes  212   a , and second terminals  456  electrically connected to the second electrode terminals  304   b  of the second address electrodes  212   b . The first and second terminals  455  and  456  may be positioned at different distances from an edge of the flexible film  308  along the y-axis. Mores specifically, a third interval d 3  between the first terminals  455  and a front edge of the flexible film  308  may be longer than a fourth interval d 4  between the second terminals  456  and the front edge of the flexible film  308 , as illustrated in  FIG. 3 . 
         [0039]    The first and second address electrodes  212   a  and  212   b  may be attached to the signal transmitter  305  as follows. First, the first address electrodes  212   a  disposed in odd columns on the second substrate  202  may be patterned. After the first address electrodes  212   a  are patterned, the first dielectric portion  213   a  may be deposited on an entire area of the second substrate  202 , such that the first address electrodes  212   a  may be embedded. It is noted that the first electrode terminals  304   a  may not be embedded by the first dielectric portion  213   a.    
         [0040]    Then, the second address electrodes  212   b  disposed in even columns on the first dielectric portion  213   a  may be patterned. After the second address electrodes  212   b  are patterned, the second dielectric portion  213   b  may be deposited on an entire area of the first dielectric portion  213   a , such that the second address electrodes  212   a  may be embedded. It is noted that the second electrode terminals  304   b  may not be embedded by the second dielectric portion  213   b . An entire width of the second dielectric layer  213   b  may be narrower than an entire width of the first dielectric layer  213   a  along the y-axis. As described above, the first and second address electrodes  212   a  and  212   b  may be formed on different planes in a multi-layered structure. 
         [0041]    Next, the signal transmitter  305  may be arranged on the second substrate  202 , so the first and second electrode terminals  304   a  and  340   b  may respectively correspond to the first and second lead terminals  455  and  456  of the signal transmitter  305 . More specifically, an alignment mark  457  formed on the flexible film  308  may be set to mutually overlap with a recognition unit (not shown) formed on the second substrate  202  to facilitate alignment therebetween, so the first and second terminals  340   a  and  304   b  may be connected to desired locations on the first and second lead terminals  455  and  456 . When the locations of the first and second lead terminals  455  and  456 , corresponding to the first and second electrode terminals  304   a  and  304   b , are determined via the above process, an anisotropic conductive film (ACF) (not shown) may be applied between the first electrode terminals  304   a  and the first lead terminals  455 , and between the second electrode terminals  304   b  and the second lead terminals  456 , in order to electrically connect the terminals via heat sealing. 
         [0042]    As described above, a PDP according to embodiments of the present invention may be advantageous in providing electrodes, e.g., address electrodes, having different lengths on different planes, so distances between the adjacent electrodes may be increased. Accordingly, upon connection of a signal transmitter to the electrodes, shorting between adjacent electrodes may be prevented or substantially minimized. Also, as a size of the PDP increases, an interval for preventing a vertical line defect of the discharge electrodes may be obtained between the terminals. 
         [0043]    Exemplary embodiments of the present invention have been disclosed herein, and although specific terms are employed, they are used and are to be interpreted in a generic and descriptive sense only and not for purpose of limitation. Accordingly, it will be understood by those of ordinary skill in the art that various changes in form and details may be made without departing from the spirit and scope of the present invention as set forth in the following claims.