CLAIM OF PRIORITY 
     This application makes reference to, incorporates the same herein, and claims all benefits accruing under 35 U.S.C. §119 from an application entitled PLASMA DISPLAY APPARATUS filed with the Korean Intellectual Property Office on 25 Feb. 2004, and there duly assigned Serial No. 10-2004-0012616. 
     BACKGROUND OF THE INVENTION 
     1. Technical Field 
     The present invention relates to a plasma display apparatus and, more particularly, to a plasma display apparatus in which the formation of non-overlapping regions between front and rear substrates of a panel is optimized to realize a more compact overall structure. 
     2. Description of the Related Art 
     A plasma display panel (PDP) provided in a plasma display apparatus is a display device that realizes the display of images through excitation of phosphors by plasma discharge. That is, vacuum ultraviolet (VUV) rays emitted from plasma obtained via gas discharge excite phosphor layers, which then emit visible red (R), green (G), and blue (B) light to thereby form images. The PDP has many advantages, including the ability to be made in large screen sizes of 60 inches and greater, a thin profile of 10 cm or less, a wide viewing angle, good color reproduction due to the self-emissive nature of the PDP (as in the case of cathode ray tubes), and high productivity and low manufacturing cost as a result of manufacturing processes that are simpler than those involved with liquid crystal displays. As a result, the PDP is experiencing increasingly widespread use in the home and in industry. 
     The plasma display apparatus has the following basic structure. A chassis base, which is made of a sturdy material with a high thermal conductivity, such as aluminum, is sandwiched between a PDP and drive circuits. The drive circuits generate signals for operating the PDP. A front cover is mounted on a front surface of the PDP, and a rear cover is mounted on a rear side of the drive circuits, thereby completing fabrication and assembly of the plasma display apparatus. 
     The PDP is classified as a DC-type device or an AC-type device depending on the drive voltage waveform applied thereto, and is further classified as an opposing discharge-type device or a surface discharge-type device depending on the structure of the discharge cells and the formation of the electrodes in the PDP. 
     In the AC-type, surface discharge-type PDP, which is the most common configuration, sustain electrodes, scan electrodes and address electrodes interact to effect plasma discharge in the PDP, thereby realizing the display of images. The sustain electrodes and the scan electrodes typically extend to right and left areas of the panel, and are connected to drive circuits provided in the rear of the PDP through an electrical coupling means, such as a flexible printed circuit (FPC). The address electrodes extend to upper and/or lower areas of the PDP, and are connected to drive circuits in a manner similar to connection of the sustain and scan electrodes. Accordingly, terminal sections of all of the electrodes are exposed at edge portions of the PDP so as to allow for connection with FPCs. The front and rear substrates of the PDP, which are sealed in positions opposing one another, are made in different sizes such that non-overlapping regions are formed along edges thereof. 
     In conventional PDPs, such non-overlapping regions are symmetrically formed such that their widths are identical between the upper and lower areas of the PDP, as well as between the right and left areas of the PDP. In the triode surface discharge PDP, the scan electrodes are individually separated since these electrodes are involved in reset and addressing discharge. In contrast, the terminals of the sustain electrodes are provided in close proximity and are all shorted. Therefore, although the non-overlapping regions must be provided with a substantial width in the areas of the terminals of the scan electrodes, this is not the case with respect to the areas of the terminals of the sustain electrodes. 
     Furthermore, when single scanning is employed, as opposed to dual scanning wherein the address electrodes extend to both upper and lower areas of the PDP, it is not necessary that non-overlapping regions be provided on the side where the address electrodes do not extend. Thus, such symmetrical formation of the non-overlapping regions results in wasted space when single scanning is employed. 
     SUMMARY OF THE INVENTION 
     The present invention comprises a plasma display apparatus in which non-overlapping regions between front and rear substrates are formed in regions where electrodes are extended. The non-overlapping regions are formed asymmetrically as needed, thereby realizing a more compact overall structure of the plasma display apparatus. 
     The plasma display apparatus comprises: a plasma display panel (PDP) which includes a first substrate and a second substrate sealed in positions opposing one another with a gap formed therebetween, the PDP having a plasma discharge structure in the gap between the first and second substrates; a chassis base mounted adjacent to one side of the PDP and substantially parallel to the PDP; and a drive circuit mounted on a side of the chassis base opposite the side adjacent to the PDP, the drive circuit being electrically connected to the PDP so as to drive the same. The first and second substrates of the PDP form an overlapping region where the first and second substrates overlie one another, and at least one pair of non-overlapping regions is formed where the first and second substrates do not overlie one another. The non-overlapping regions are asymmetrically formed about the overlapping region. 
     The asymmetrically formed non-overlapping regions have different widths, each of the widths being formed as an average distance between a corresponding adjacent edge of the overlapping region and an outermost edge of the corresponding non-overlapping region. 
     The first and second electrodes are formed in a substantially uniform manner with respect to one edge of the PDP, and they extend into non-overlapping regions on opposite sides of the PDP. Terminal regions of the first electrodes are shorted in close proximity to one another, and the width of the non-overlapping region into which the second electrodes extend is greater than the width of the non-overlapping region into which the first electrodes extend. 
     The width of the non-overlapping region, into which the second electrodes extend, is greater than the width of the non-overlapping region, into which the first electrodes extend by 5 to 30 mm. 
     The address electrodes extend into one of the non-overlapping regions, and the width of the non-overlapping region into which the address electrodes extend is greater than a width of the non-overlapping region positioned on an opposite side of the PDP. 
     The width of the non-overlapping region, into which the address electrodes extend, is greater than the width of the non-overlapping region positioned on the opposite side of the plasma display panel by 5 to 30 mm. 
     Alternatively, substantially no non-overlapping region is present on a side of the PDP opposite the non-overlapping region into which the address electrodes extend. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       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: 
         FIG. 1  is an exploded perspective view of a plasma display apparatus according to a first exemplary embodiment of the present invention; 
         FIG. 2  is a schematic plan view of the PDP of  FIG. 1  used to illustrate a mounting structure between front and rear substrates; 
         FIG. 3  is a schematic plan view of a PDP according to a second exemplary embodiment of the present invention used to illustrate a mounting structure between front and rear substrates; and 
         FIG. 4  is a schematic plan view of a PDP according to a third exemplary embodiment of the present invention used to illustrate a mounting structure between front and rear substrates. 
     
    
    
     DETAILED DESCRIPTION 
     Exemplary embodiments of the present invention will now be described with reference to the drawings. 
       FIG. 1  is an exploded perspective view of a plasma display apparatus according to a first exemplary embodiment of the present invention, and  FIG. 2  is a schematic plan view of the PDP used to illustrate a mounting structure between front and rear substrates. 
     The plasma display apparatus includes the main elements of a PDP  12  and a chassis base  16 , which are provided substantially parallel to one another. The PDP  12  is mounted on one side of the chassis base  16 , and drive circuits (not shown) for driving the PDP  12  are mounted on an opposite side of the chassis base  16 . A front cover (not shown) is positioned on an outer surface of the PDP  12  (i.e., on a side opposite that side adjacent to the chassis base  16 ), and a rear cover (not shown) is positioned on an outer surface of the chassis base  16  (i.e., on the side on which the drive circuits are mounted). The front cover and the rear cover are interconnected to thereby complete the plasma display apparatus. 
     The PDP  12  includes a first substrate (hereinafter referred to as a front substrate)  12 A and a second substrate (hereinafter referred to as a rear substrate)  12 B. The front substrate  12 A and the rear substrate  12 B are provided in opposition to one another and are sealed in this state. Provided in a gap between the front substrate  12 A and the rear substrate  12 B so as to form a plasma discharge structure are first electrodes (hereinafter referred to as sustain electrodes)  21 , second electrodes (hereinafter referred to as scan electrodes)  23 , and address electrodes  25 . The sustain electrodes  21  and the scan electrodes  23  are formed along one direction (direction y in  FIG. 2 ), and extend into regions on respective opposite sides of the PDP  12 . The address electrodes  25  are formed along a direction substantially perpendicular to the direction along which the sustain electrodes  21  and the scan electrodes  23  extend (direction z in  FIG. 2 ). The address electrodes  25  may extend into either or both of the upper and lower regions of the PDP  12 . In this embodiment, the address electrodes  25  extend into the lower region of the PDP  12 . 
     In order to display discharge cells of the PDP  12  in a desired pattern or by a transmitted signal, a drive voltage must be applied to each of these electrodes in a predetermined sequence. The application of the drive voltage may be designated according to predetermined time intervals of a reset period, a scan period, and a (discharge) sustain period. In the reset period, the wall charges of all of the discharge cells are made uniform. In the scan period, the discharge cells where display is to take place are selected, and discharge is effected for these discharge cells. In the sustain period, discharge of the discharge cells selected in the scan period is continuously maintained so as to realize the emission of visible light. 
     In the scan period, a scan voltage is sequentially applied to the scan electrodes  23  such that discharge occurs between the scan electrodes  23  and the address electrodes  25 , thereby selecting the discharge cells where discharge is to take place (discharge at this point is referred to as addressing discharge). Wall charges are accumulated within the selected discharge cells such that, when a discharge sustain voltage is alternatingly applied to the sustain electrodes  21  and the scan electrodes  23  in the subsequent discharge sustain period, display discharge is effected. 
     Unlike the sustain electrodes  21 , which are active only in the discharge sustain period, the scan electrodes  23  are active not only during the discharge sustain period, but also during the reset and scan periods. Therefore, the sustain electrodes  21  and the scan electrodes  23  may differ in both function and formation. In particular, since the same voltage is applied to the sustain electrodes  21  when the sustain electrodes  21  are active only during the discharge sustain period, terminal regions of the sustain electrodes  21  are shorted in proximity to one another, as shown in  FIG. 2 . 
     In this exemplary embodiment, non-overlapping edge portions of the front substrate  12 A and the rear substrate  12 B of the PDP  12  are formed asymmetrically. Such a configuration is adopted on the basis of the electrode formation as described above. That is, the front substrate  12 A and the rear substrate  12 B form an overlapping region  13 D in which they overlie each other, and non-overlapping regions  13 X,  13 Y,  13 A in which no overlapping between the front and rear substrates  12 A,  12 B occurs. The non-overlapping regions  13 X,  13 Y,  13 A are asymmetrically formed with respect to a center of the PDP  12 , and have different widths. The widths of the non-overlapping regions  13 X,  13 Y,  13 A are defined as average distances from corresponding adjacent edges of the overlapping region  13 D to outermost edges of the non-overlapping regions  13 X,  13 Y,  13 A. 
     The width of the non-overlapping region  13 Y, into which terminal regions of the scan electrodes  23  extend, is greater than the width of the non-overlapping region  13 X, into which terminal regions of the sustain electrodes  21  extend. Preferably, the width of the non-overlapping region  13 Y, into which the scan electrodes  23  extend, is greater than the width of the non-overlapping region  13 X, into which the sustain electrodes  21  extend by 5 to 30 mm. 
     Further, the non-overlapping region  13 A is formed only in the lower region of the PDP  12  because this is where the address electrodes  25  extend, that is, because the address electrodes  25  do not extend into both upper and lower regions of the PDP  12 . The width of the non-overlapping region  13 A is sufficient to allow for the required electrical coupling of the address electrodes  25 . In the case where a non-overlapping region is also formed in the upper region of the PDP  12 , the width of the non-overlapping region  13 A is greater than a width thereof by 5 to 30 mm. 
       FIG. 3  is a schematic plan view of a PDP according to a second exemplary embodiment of the present invention used to illustrate a mounting structure between front and rear substrates. The same reference numerals will be used for elements identical to those of the first exemplary embodiment. 
     In the second exemplary embodiment, the front substrate  32 A and the rear substrate  32 B of PDP  32  form an overlapping region  33 D in which they overlie each other, and non-overlapping regions  13 X,  13 Y,  33 A,  34 A in which no overlapping between the front substrate  32 A and rear substrate  32 B occurs. The non-overlapping regions  13 X,  13 Y,  33 A,  34 A are asymmetrically formed with respect to the center of the PDP  32 , and have different widths. 
     The width of the non-overlapping region  13 Y, into which terminal regions of scan electrodes  23  extend, is greater than the width of the non-overlapping region  13 X, into which terminal regions of sustain electrodes  21  extend, as in the first exemplary embodiment. However, in this embodiment, address electrodes  35  extend into both upper and lower regions of the PDP  32 , and therefore, the non-overlapping regions  33 A and  34 A are formed in the lower and upper regions, respectively, of the PDP  32 . The widths of the non-overlapping regions  33 A and  34 A are substantially identical. Such a configuration is applied to a dual-scanning PDP where scanning is performed simultaneously in two directions during the scan period. 
       FIG. 4  is a schematic plan view of a PDP according to a third exemplary embodiment of the present invention used to illustrate a mounting structure between front and rear substrates. The same reference numerals will be used for elements identical to those of the first exemplary embodiment. 
     In the third exemplary embodiment, the front substrate  42 A and the rear substrate  42 B of PDP  42  form an overlapping region  43 D in which they overlie each other, and non-overlapping regions  13 A,  43 X,  43 Y in which no overlapping between the front substrate  42 A and rear substrate  42 B occurs. 
     As in the first exemplary embodiment, the non-overlapping region  13 A is formed only in the lower region of the PDP  42  because this is where address electrodes  25  extend, that is, because the address electrodes  25  do not extend into both upper and lower regions of the PDP  42 . The width of the non-overlapping region  13 A is sufficient to allow for the required electrical coupling of the address electrodes  25 . When a non-overlapping region is also formed in the upper region of the PDP  42 , the width of the non-overlapping region  13 A is greater than a width thereof by 5 to 30 mm. 
     In contrast to the first exemplary embodiment, however, the width of the non-overlapping region  43 X, into which terminal regions of sustain electrodes (not shown) extend, is substantially the same as a width of the non-overlapping region  43 Y, into which terminal regions of the scan electrodes (not shown) extend. Thus, the non-overlapping regions  43 X,  43 Y are symmetrical about a center of the PDP  42 . Such a configuration may be applied to a PDP in which the terminal regions of the sustain electrodes are not shorted, and in which the sustain electrodes individually receive different drive voltages as with the scan electrodes. 
     In the plasma display apparatus of the present invention described above, the edge regions into which the electrodes extend are optimally formed so that unneeded areas may be removed, thereby allowing the overall size of the plasma display apparatus to be reduced. Manufacturing cost is also minimized as a result. 
     Although embodiments of the present invention have been described in detail hereinabove, it should be clearly understood that many variations and/or modifications of the basic inventive concepts herein taught, which may appear to those skilled in the present art, will still fall within the spirit and scope of the present invention, as defined in the appended claims.
A plasma display apparatus comprises: a plasma display panel including first and second substrates disposed in opposition to one another with a gap formed therebetween; a chassis base disposed on one side of the plasma display panel; and a drive circuit disposed on an opposite side of the chassis base for driving the plasma display panel. The first and second substrates of the plasma display panel form an overlapping region in which the first and second substrates overlie one another, and at least one pair of non-overlapping regions in which the first and second substrates do not overlie one another. The non-overlapping regions are asymmetrically formed about the overlapping region.