Patent Publication Number: US-6707259-B2

Title: Gas discharge panel

Description:
TECHNICAL FIELD 
     The present invention relates to gas discharge panels such as plasma display panels and the like. 
     BACKGROUND ART 
     Plasma display panels (PDPs) are one of the various types of plasma display apparatuses. Given their relative suitability for thin, large-screen applications, PDPs are currently attracting attention as the possible displays of the future, and 60-inch class models are already available on the market. 
     FIG. 42 is a partial perspective view showing a main structure of a known surface-discharge AC-type PDP. In FIG. 42, a thickness of the PDP is in the z direction and the panel surface of the PDP lies parallel to the xy plane. The PDP includes a front panel  20  and a back panel  26  arranged so that the main surfaces of each panel face each other. 
     A front panel glass  21  forms a substrate of front panel  20 . Plural pairs of display electrodes  22  and  23  (i.e. scan electrode  22  and sustain electrode  23 ) extending in the x direction are arranged on a main surface of front panel glass  21  so as to enable a surface discharge to be conducted between the electrodes  22  and  23  in each pair. The electrodes  22  and  23  can be formed, for example, from a mixture of Ag and glass. 
     Each scan electrode  22  is electrically independent with respect to its power supply. In contrast, each sustain electrode  23  is connected to the same power supply. A dielectric layer  24  and a protective layer  25 , both of which are formed from an insulating material, are coated in the stated order over the surface of front panel glass  21  on which the pairs of display electrodes are arranged. 
     A back panel glass  27  forms a substrate of back panel  26 . A plurality of address electrodes  28  extending in the y direction is arranged in a stripe-pattern on a main surface of back panel glass  27 , and a predetermined space is provided between adjacent address electrodes. The address electrodes may be formed from a mixture of Ag and glass. 
     A dielectric layer  29  formed from an insulating material is coated over the surface of back panel glass  27  on which address electrodes  28  are arranged. Barrier ribs  30  are provided between adjacent address electrodes  28  on dielectric layer  29 . Phosphor layers  31 ,  32 , and  33  corresponding to the colors red (R), green (G) and blue (B) are formed between adjacent barrier ribs  30 , the phosphor layers being formed on the barrier rib walls and over the dielectric layer  29  between adjacent barrier ribs. 
     Front panel  20  and back panel  26  as described above are arranged to face each other such that address electrodes  28  extend in an orthogonal direction to display electrodes  22  and  23 . 
     Front panel  20  and back panel  26  are sealed together around their respective peripheries using a sealing material such as frit glass, and a vacuum is created within the space enclosed therebetween. 
     In should be noted that only one of each of electrodes  22 ,  23  and  28  has been shown in FIG. 42 for ease of description. The known PDP as described here actually includes a plurality of each of these electrodes. 
     A discharge gas (enclosed gas) that includes Xe is enclosed at a predetermined pressure (approx. 40 kPa to 66.5 kPa in conventional PDPS) within the sealed space between the front and back panels. 
     A discharge space  38  is thus formed in the space defined between dielectric layer  24  of front panel  20 , phosphor layers  31 - 33  of back panel  26 , and adjacent barrier ribs  30  interposed therebetween Furthermore, a plurality of cells (not depicted in FIG. 42) used in image display is provided in discharge space  38 , each cell being formed in the region where a single address electrode  28  extends across a single pair of display electrodes  22  and  23 . FIG. 43 shows the matrix of the PDP formed by the plural pairs of display electrodes  22 ,  23  (N line) and the plurality of address electrodes  28  (M columns). 
     When the PDP is driven, a discharge is initiated between address electrode  28  and either display electrode  22  or  23  in each of the cells. Ultraviolet light (Xe resonance line; wave length approx. 147 nm) having short wavelengths is generated as a result of a discharge that. then occurs between display electrodes  22  and  23  in each pair, the generated ultraviolet light striking phosphor layers  31  to  33  and exciting them to emit visible light. Image display is achieved as a result. 
     The following is a detailed description of a prior art method for driving the known PDP with reference to FIGS. 44 and 45. 
     FIG. 44 is a conceptual block diagram showing an image display apparatus (PDP display apparatus) using the known PDP. FIG. 45 shows exemplary drive waveforms applied to each of the electrodes in the PDP. 
     As shown in FIG. 44, in order to drive the PDP, the PDP display apparatus includes the following elements: a frame memory  10 , an output processing circuit  11 , an address electrode drive apparatus  12 , a sustain electrode drive apparatus  13 , and a scan electrode drive apparatus  14 . Each of electrodes  22 ,  23  and  28  are connected to scan electrode drive apparatus  14 , sustain electrode drive apparatus  13 , and address electrode drive apparatus  12 , respectively. Elements  12 ,  13  and  14  are connected to output processing circuit  11 . 
     When the PDP is driven, image information inputted into the PDP display apparatus from an external source is initially stored in frame memory  10 , and then based on timing information, the image information is transferred from frame memory  10  to output processing circuit  11 . Then, based on the image information and the timing information, output processing circuit  11  becomes operational. Output processing circuit  11  outputs instructions to the elements  12 ,  13  and  14 , and applies pulse voltages to each of electrodes  22 ,  23  and  28 , thereby conducting the image display. 
     As shown in FIG. 45, when the PDP is driven, a setup pulse is applied to scan electrodes  22 , initializing a wall charge within each of the cells. Next, a scan pulse and a write pulse are applied respectively to scan electrode  22  and sustain electrode  23  positioned at the top of the screen (i.e. in the y direction), thus initiating a write discharge. As a result of the write discharge, wall charge is stored on the surface of dielectric layer  24  in each of the cells corresponding to the electrodes  22  and  23  that have been applied with the pulses. 
     Continuing on, a scan pulse and a write pulse are then applied respectively to scan electrode  22  and sustain electrode  23  in the line second from the top of the screen, and wall charge is stored on dielectric layer  24  in each of the cells corresponding to the electrodes  22  and  23  in the stated line. One screen of latent image is thus written by repeating this process for all display electrodes  22  and  23  forming the display surface. 
     Next, a sustain discharge is conducted by grounding address electrodes  28  and applying sustain pulses alternately to scan electrodes  22  and sustain electrodes  23 . A discharge is generated in the cells storing wall charge on dielectric layer  24  when the potential of the surface of layer  24  increases above the discharge initiating voltage in the respective cells. The sustain discharge is maintained in the cells applied with the write pulse for the duration that the sustain pulses are applied (i.e. sustain period). Erase pulses, each of short duration, are then applied so as to weaken the discharge and eliminate the wall charge, thereby serving to erase the latent image. 
     In television image display according to the NTSC standard, one image is composed of 60 fields per second. Primarily, a PDP is only capable of expressing the two states of “on” and “off.” Thus, in order to display the intermediate color gradations, a method is adopted according to which the “on” periods of each of the colors red (R), green (G) and blue (B) are timeshared and one field is divided into a plurality of subfields. The intermediate color gradations can thus be expressed depending on the combination of “on” and “off” subfields. 
     The subfield division method used by the known AC PDP and shown in FIG. 46 expresses 256 color gradations. The ratio of sustain pulses applied during the sustain periods in each subfield is layered in a binary scale, an example of which is 1, 2, 4, 8, 16, 32, 64, 128. 256 color gradations can be expressed by varying the combination of these eight bits. 
     As described above in relation to the method for driving the prior art PDP, display is achieved by a consecutive sequence of setup, write, sustain, and erase periods. 
     However, in a day and age when any viable reduction in the energy consumption of electrical appliances is greatly valued, much emphasis has naturally been placed on reducing the power requirements of PDPs. In the last few years, an increasing emphasis has been placed on technology that realizes such power reductions, given that the general push toward larger screens and higher definition image display has resulted in recently developed PDPs exhibiting a tendency for increased power consumption. For these reasons, technology that reduces the power consumption of PDPs is most desirable. 
     However, simply reducing the power consumption of PDPs is not in itself enough, since this will only weaken the discharge occurring between the display electrodes, and cause an insufficient illumination. Therefore, any reductions in power consumption must be accompanied with the ability to achieve a satisfactory display capacity (i.e. a satisfactory luminous efficiency). Since insufficient illumination causes a drop in PDP display capacity, simply reducing the power usage of PDPS is not likely to realize any improvements in luminous efficiency. 
     Research aimed at improving luminous efficiency is currently being conducted, an example of which includes trying to improve the efficiency at which the phosphors convert ultraviolet light into visible light. However, significant improvements are yet to be realized and further research into this area is still required. 
     Thus, at this point in time, optimizing the luminous efficiency in gas discharge panels such as PDPs is considered to involved a great many difficulties. 
     DISCLOSURE OF INVENTION 
     In view of the issues discussed above, an objective of the present invention is to provide a gas discharge panel having a high luminous efficiency and an excellent display capacity. 
     In order to resolve the above issues, the gas discharge panel of the present invention includes (i) a plurality of cells arranged in a matrix between a pair of opposing substrates, the cells being filled with a discharge gas, and (ii) plural pairs of display electrodes arranged on a surface of one of the substrates so as to extend through the plurality of cells, each pair of display electrodes being composed of a sustain electrode and a scan electrode that define a main discharge gap therebetween. Furthermore, each sustain electrode and scan electrode includes a plurality of line parts that extend in a row direction of the matrix. By adjusting the main discharge gap and a line part gap between adjacent line parts, it is possible to generate a discharge current waveform of the display electrodes that has a single peak when the gas discharge panel is driven. 
     Specifically, it is preferable for at least one of the scan electrode and the sustain electrode within each cell to be composed of three or more line parts. It is furthermore preferable for a pitch of the line part gaps in each cell to decrease as the distance separating the respective line part gap from the main discharge gap increases. 
     Discharge current wavelengths having single peaks can be achieved according to this structure, thereby enabling the discharge illumination generated by a single drive pulse to be completed within 1 μs. Also, the fact that the period from when the drive pulse is applied when the discharge current reaches a maximum value (i.e. the discharge delay period) is only short at approximately 0.2 μs, allows the gas discharge panel to be driven at the high speed of a few μs. 
     Furthermore, the fact that display electrodes  22  and  23  are arranged in lines allows for a reduction in the amount of static electricity arising from the discharge in comparison to when the display electrodes are arranged in bands as per the prior art. Generally, when pairs of display electrodes are arranged in lines, the tendency is for the discharge to disperse, the discharge current waveform to develop multiply peaks, and the discharge initiating voltage to increase, thereby invariably resulting in increased power consumption. However, because the discharge current waveform of the present invention as described above forms a single peak, it is possible to drive the gas discharge panel at a relatively low voltage, thereby suppressing power consumption below existing levels and achieving a favorable luminous efficiency (drive efficiency). 
     Consequently, the gas discharge panel of the present invention is able to achieve excellent luminous efficiency and high-speed driving by securing a discharge voltage waveform having a single peak while at the same time reducing power consumption through the provision of display electrodes  22  and  23  having a reduced surface area (i.e. line parts  22   a - 22   c ,  23   a - 23   c  in FIG. 1) in comparison to known display electrodes. 
     Furthermore, in the present invention, a discharge voltage waveform having an excellent single peak may be achieved by reducing the, pitch of the line part gaps either geometrically or arithmetically. 
     Also, in regard to the actual construction of the present invention, it is preferable to establish the cell length in the column direction of the matrix to be in a range of 480 μm to 1400 μm, and to satisfy the expression G-60 μm≦S≦G+20 μm with respect to each cell, where S is the width of an average line part gap in a respective cell, and G is the width of the main discharge gap. 
     Furthermore, the line parts positioned furthest from the main discharge gap in each cell may be wider than (i) the other line parts in the cell or (ii) an average width of all the line parts in the cell. 
     In addition, the line parts within each cell may increase in width as the distance separating the respective line part from the main discharge gap increases. 
     Here, it is preferable to establish the width of the lineparts to satisfy the expression L ave ≦L n ≦{0.35P−(L 1 +L 2 +. . . L n−1 )} with respect to one of the sustain electrode and scan electrode in each cell, where P is the cell length in the column direction of the matrix, L n  is the width of the line parts positioned furthest from the main discharge gap, L ava  is the average width of all of the line parts in the cell, and the sustain electrode or scan electrode includes n line parts. 
     Also, it is preferable for the resistance value R of the line parts positioned furthest from the main discharge gap within each the cell to be in a range of 0.1 Ω≦R≦80 Ω. 
    
    
     BRIEF DESCRIPTION OF DRAWINGS 
     FIG. 1 is a view from above of display electrodes in a PDP of the present invention according to an embodiment 1; 
     FIG. 2 is a waveform diagram showing a change over time of a drive voltage waveform and a discharge current waveform according to embodiment 1; 
     FIG. 3 is a graph showing a relationship between an “on” voltage (drive voltage), a differential S-G, and a discharge current peak number, where G is a main discharge gap, and S (=a first line part gap S 1 =a second line part gap S 2 ) is a line part gap; 
     FIG. 4 shows a view from above of the display electrodes according to an embodiment 2; 
     FIG. 5 is a graph showing a relationship between main discharge gap G, the first line part gap S 1 , the second line part gap S 2 , and the discharge current peak number in the PDP according to embodiment 2; 
     FIG. 6 shows a view from above of the display electrodes according to an embodiment 3; 
     FIG. 7 is a graph showing a relationship between main discharge gap G, an average line part gap S ave , a line part gap differential ΔS, and the number of peaks of the discharge current waveforms in the PDP according to embodiment 3; 
     FIG. 8 compares a capacity of the PDP of embodiments 2 and 3; 
     FIG. 9 shows a view from above of the display electrodes according to an embodiment 4; 
     FIG. 10 is a graph showing an exemplary discharge illumination waveform in the PDP according to embodiment 4; 
     FIG. 11 shows a view from above of the display electrodes according to an embodiment 5; 
     FIG. 12 is a graph showing a relationship between (i) a ratio S 1 /G with respect to main discharge gap G and the first line part gap S 1 , and (ii) a discharge current peak number with respect to a line part gap ratio α=S n+1 /S n  in the PDP according to embodiment 5; 
     FIG. 13 shows a view from above of the display electrodes according to an embodiment 6; 
     FIG. 14 is a waveform diagram showing a change over time of the drive voltage waveform and the discharge current waveform in the PDP according to embodiment 6; 
     FIG. 15 shows a view from above of the display electrodes according to an embodiment 7; 
     FIG. 16 is a graph showing the relationship between power and brightness in the PDP according to embodiments 6 and 7; 
     FIG. 17 shows a view from above of the display electrodes according to an embodiment 8; 
     FIG. 18 is a graph showing a relationship between blackness and photopic contrast when L 4  is varied in the PDP according to embodiment 8; 
     FIG. 19 shows a view from above of the display electrodes according to an embodiment 9; 
     FIG. 20 is a cross-sectional view along a Y—Y axis of a section of the PDP according to an embodiment 10; 
     FIG. 21 shows a view from above of the display electrodes according to an embodiment 11; 
     FIG. 22 is a graph showing a change over time of the drive voltage waveform and the discharge current waveform in the PDP according to embodiment 11; 
     FIG. 23 shows a view from above of the display electrodes according to an embodiment 12; 
     FIG. 24 shows a view from above of the display electrodes according to an embodiment 13; 
     FIG. 25 shows a view from above of the display electrodes according to an embodiment 14; 
     FIG. 26 shows a view from above of the display electrodes according to an embodiment 15; 
     FIG. 27 shows a view from above of the display electrodes according to an embodiment 16; 
     FIG. 28 shows a view from above of the display electrodes according to an embodiment 17; 
     FIG. 29 is a graph showing a relationship between a display electrode surface area and brightness when W 1 =W 2  in the PDP according to embodiment 17; 
     FIG. 30 shows a view from above of the display electrodes according to an embodiment 18; 
     FIG. 31 is a graph showing the relationship between the display electrode surface area and brightness when W 1 =W 2  in the PDP according to embodiment 18; 
     FIG. 32 shows a view from above of the display electrodes according to an embodiment 19; 
     FIG. 33 is a graph showing the relationship between the display electrode surface area and brightness when W 1 =W 2  in the PDP according to embodiment 19; 
     FIG. 34 shows a view from above of the display electrodes according to an embodiment 20; 
     FIG. 35 is a graph showing the relationship between the display electrode surface area and brightness when W 1 =W 2  in the PDP according to embodiment 20; 
     FIG. 36 is a graph showing a result of a test calculation of brightness distribution across cells according to embodiment 20; 
     FIG. 37 shows a view from above of the display electrodes according to an embodiment 21; 
     FIG. 38 is a graph showing the relationship between the display electrode surface area and panel brightness when W 1 =W 2  in the PDP according to embodiment 21; 
     FIG. 39 shows a view from above of the display electrodes according to an embodiment 22; 
     FIG. 40 shows a view from above of the display electrodes according to an embodiment 23; 
     FIG. 41 shows a view from above of the display electrodes according to an embodiment 24; 
     FIG. 42 is a cross-sectional view of a main section of a known surface discharge AC PDP; 
     FIG. 43 is a graph showing a matrix composed of plural pairs of display electrodes  22  and  23  (N lines) and a plurality of address electrodes  28  (M columns); 
     FIG. 44 is a conceptual block diagram of an image display apparatus using the known PDP; 
     FIG. 45 shows exemplary waveforms applied to each of the electrodes (scanelectrode, sustain electrode, address electrode) in the known PDP; and 
     FIG. 46 shows a method for dividing a field into subfields in the known PDP in order to express 256 color gradations. 
    
    
     BEST MODE FOR CARRYING OUT THE INVENTION 
     Since the characteristics of the PDP of the present invention relate mainly to the structure of the display electrodes, the following description will focus on the display electrodes The general structure of the PDP of the present invention is otherwise substantially the same as that of the prior art PDP. 
     Embodiment 1 
     1-1 Structure of the Display Electrodes 
     FIG. 1 is a schematic view from above the structure of the display electrodes according to embodiment 1. 
     As shown in FIG. 1, embodiment 1 is characterized in that display electrodes  22  and  23  (scan electrode  22 , sustain electrode  23 ) forming a pair in a cell defined between adjacent barrier ribs  30  are each divided into three line parts  22   a  to  22   c  and  23   a  to  23   c , respectively. In the given example, a cell pitch (i.e. a cell length in the y direction) P is 1.08 mm, a main discharge gap G is 80 μm, a line part width L 1  to L 3  is 40 μm, a first line part gap S 1  is 80 μm, and a second line part gap S 2  is 80 μm. Display electrodes  22  and  23  are composed of a metallic substance such as Ag or Cr/Cu/Cr. 
     One pixel is composed of three cells corresponding to the colors red (R), green (G) and blue (B), and a cell width in the x direction with respect to the cell pitch P is P/3. 
     In the given example the electrodes have been arranged so that the discharge current waveform forms a single peak when the PDP is driven, thus allowing for excellent luminous efficiency to be achieved. 
     1-2 Effects of Embodiment 1 
     Generally, when the display electrodes are configured as a plurality of lines, the discharge current waveform tends to have multiply peaks during the discharge period. A discharge arising from a discharge current waveform having multiple peaks is readily affected by discharges generated from prior discharge current waveforms (i.e. a priming effect caused by residual ions and metastable particles, etc). Specifically, the time taken to generate a discharge may vary as a result of prior discharges, and the illumination brightness and luminous efficiency may vary as a result of voltage drops, and the like. Consequently, gradation controls easily become unstable when the discharge current waveforms have multiply peaks. When the objective is to achieve quality full-color moving image display in television receivers, and the like, this is a serious problem. 
     In contrast, by achieving a discharge current waveform having a single peak, embodiment 1 allows for a stable sustain discharge to be conducted, and thus stable gradation controls can be implemented by means of pulse modulation. 
     FIG. 2 shows the variation over time of the discharge current waveform and the drive voltage waveform of the PDP according to embodiment 1. As shown in FIG. 2, because the discharge current waveform has a single peak, a discharge illumination generated by a single drive pulse can be completed within 1 μs. In addition, because the time taken for the drive pulse to reach a maximum value after being applied (i.e. the discharge delay period) is short at approximately 0.2 μs, high-speed driving in the range of a few microseconds is possible. According to embodiment 1, achieving a single-peaked discharge current waveform makes it possible to also achieve a singe peak with respect to the discharge illumination waveform. As shown in FIG. 2, it is particularly desirable for a half-width Thw of the single-peaked discharge illumination waveform to be in a range 50ns≦Thw≦700 μs. 
     FIG. 3 shows the relationship between a discharge current peak number, an “on” voltage, and a differential S-G when the PDP is driven using prior art drive waveforms (see FIG.  47 ), where s is the line part gap (S 1 =S 2 ) and G is the main discharge gap. As shown in FIG. 3, if the line part gaps S 1  and S 2  (“S” in FIG. 3) are smaller than main discharge gap G (i.e. when S-G is negative), a discharge current waveform having a single peak can be achieved, and high-speed driving of the PDP can be achieved as a result. 
     Furthermore, because display electrodes  22  and  23  are configured as lines in embodiment 1, it is possible to reduce the amount of static electricity arising from the discharge in comparison to known structures in which the discharge electrodes are arranged as bands. Consequently, it is possible to reduce power consumption and achieve excellent luminous efficiency (drive efficiency). 
     Thus, by achieving discharge current waveforms having a single peak while at the same time reducing power consumption by providing display electrodes  22  and  23  (line parts  22   a  to  22   c ,  23   a  to  23   c ) having a smaller surface area than known display electrodes, embodiment 1 realizes a PDP having excellent luminous efficiency and capable of high-speed driving. 
     Here, a discharge current waveform having a “single peak” is defined to include a waveform having more than one peak but where the other peaks are at 10% smaller than the highest peak. 
     According to embodiment 1, effects identical to those described above can also be achieved by establishing cell pitch P to be 0.5mm≦P≦1.4 mm, main discharge gap G to be 60 μm≦G≦140 μm, line part widths L 1  to L 3  to be 10 μm≦L 1 , L 2 , L 3 ≦60 μm, and first and second line part gaps S 1  and S 2  to be 50 μm≦S 1 ,S 2 ≦140 μm. 
     It is preferable for the cell length (cell pitch P) to be in a range of 480 μm to 1400 μm. 
     It is furthermore preferable to satisfy the expression G-60 μm≦S≦G+20 μm with respect to each cell, where S is an average line part gap of all the line parts in the cell, and G is the main discharge gap. 
     Here, it is possible for the pitch between adjacent barrier ribs to be other than P/3. For example, the brightness balance of each of the colors RGB can be improved by establishing a different barrier rib pitch for each cell, such that the barrier rib pitch ratio with respect to the red (R), green (G), and blue (B) cells is P/3:P/3.75:P/2.5, respectively. 
     1-3 Manufacture of the PDP 
     An exemplary manufacturing method for the PDP of embodiment 1 will now be described. The manufacturing method described here is substantially the same as the manufacturing methods employed in other embodiments of the present invention. 
     1-3-1 Manufacture of the Front Panel 
     The front panel glass forming the substrate of the front panel is composed of soda lime glass approximately 2.6 mm thick, and display electrodes are provided on a surface thereof. In the given example, thick film processes are used to form the display electrodes, which are metallic electrodes composed of Ag. 
     To form the display electrodes, a metallic (Ag) power and a photosensitive resin (i.e. a photodegradable resin) are mixed together in an organic vehicle to make a photosensitive paste. A layer of paste is applied to one surface of the front panel glass and the paste layer is covered with a mask that marks out the pattern of the display electrodes. The paste layer covered by the mask is then exposed, developed, and baked (baking temp of approx. 590% to 600° C.). In comparison to known screen printing methods which only allow for a minimum 100 μm line width, this method of forming the display electrodes makes it possible to form thin lines of approximately 30 μm. Apart from Ag, the metallic electrodes may be formed from materials such as Pt, Au, Al, Ni, Cr, tin oxide, and indium oxide. 
     It is furthermore possible to use methods other than the one described above to form the electrodes. For example, the electrodes may be formed by etching a film of electrode material applied using evaporation, sputtering, or similar techniques. 
     Next, a protective layer having a thickness of 0.3 μm to 0.6 μm is formed over the dielectric layer using methods such as evaporation and chemical evaporation (CVD) Magnesium oxide (Mgo) is a suitable material from which to form the protective layer. 
     Thus completes the manufacture of the front panel. 
     1-3-2 Manufacture of the Back Panel 
     The back panel glass forming the substrate of the back panel is composed of soda lime glass approximately 2.6 mm thick. Address electrodes having a thickness of approximately 5 μm are formed by screen-printing a dielectric material composed primarily of Ag in a regularly spaced stripe-pattern on a surface of the back panel glass. In a 40-inch class NTSC or VGA format PDP, for example, the space between adjacent address electrodes is set to be no more than approximately 0.4 mm. 
     A dielectric film having a thickness of approximately 20 μm to 30 μm is formed by coating a lead-based glass paste over the surface of the back panel glass of which the address electrodes have been formed, and baking the applied paste. 
     Barrier ribs having a height of approximately 60 μm to 100 μm are formed by applying a lead-based glass material (i.e. same as used in the paste for the dielectric film) in the space between adjacent address electrodes. The barrier ribs may be formed, for example, by repeatedly screen-printing a paste that includes the glass material, and then baking the screen-printed paste. 
     After the barrier ribs have been formed, phosphor layers are formed by applying a phosphor ink that includes the colors red (R), green (G), and blue (B) to the barrier rib walls and to the uncovered surface of the dielectric layer lying between adjacent barrier ribs. Here, one color is applied within each space. The applied phosphor ink is then dried and baked. 
     The following is an example of the phosphor materials commonly used in PDPs. 
     Red Phosphors: (Y x G d 1−x ) BO:Eu 3+   
     Green Phosphors: Zn 2 SiO 4 : Mn 3+   
     Blue Phosphors: BaMgAl 10 O 17 :Eu 3+ (or BaMgAl 14 O 23 :Eu 3+ ) 
     The phosphor material may be, for example, a power having an average particle diameter of approximately 3 μm. Although there are various methods for applying the phosphor ink formed from the phosphor material, a conventional meniscus method is used in the given example. This method involves the phosphor ink being sprayed from a fine nozzle so as to form a meniscus (i.e. a bridge caused by surface tension). This method allows the phosphor ink to be applied evenly to the target area. Other methods that may be used to apply the phosphor layers include the screen-printing method. 
     Thus completes the manufacture of the back panel. 
     Although the front panel glass and back panel glass were described above as being composed of soda lime glass, this was merely by way of example, and other materials may be used. 
     1-3-3 Completion of the PDP 
     The front and back panels are affixed together using a glass sealant. The discharge space sealed between the front and back panels is then evacuated to form a high vacuum (approx. 1.1×10 −10  Pa), and a discharge gas is enclosed within the discharge space at a predetermined pressure (2.7×10 5  Pa in the given example). The discharge gas may, for example, be a gas mixture composed primarily of Ne and Xe, or He, Ne, and Xe, or He, Ne, Xe, and Ar. 
     Embodiment 2 
     FIG. 4 is a view from above of the display electrodes according to embodiment. 2. In this embodiment, display electrodes  22  and  23  include line parts  22   a  to  22   c  and  23   a  to  23   c , respectively. Embodiment 2 is characterized in that the first and second line part gaps S 1  and S 2  in each cell decrease in width as the distance from main discharge gap G increases. In the given example, cell pitch P is 1.08 mm, main discharge gap G is 80 μm, line part widths L 1  to L 3  are 40 μm, first line part gap S 1  is 90 μm, and second line part gap S 2  is 70 μm. 
     In addition to substantially the same effects as embodiment 1, the structure according to embodiment 2 achieves the following. 
     FIG. 5 is a graph showing the relationship between main discharge gap G, first line part gap S 1 , second line part gap S 2 , and the discharge current peak number according to embodiment 2. As shown in FIG. 5, when line part gaps S 1  and S 2  are approximately 10 μm wider than main discharge gap G, and when gap S 2  is smaller than gap S 1 , a single discharge peak can be achieved. Controlling the gradation by means of pulse modulation can therefore be conducted in a stable environment, and high-speed driving can be achieved. Expansion of the discharge to first line part gap S 1  occurs relatively smoothly due to gap S 1  being positioned near to main discharge gap G, which is where the discharge was initially generated. 
     Although the various measurement within each of the discharge cells according to embodiment 2 are as given above, the present invention is not limited to these measurements. For example, the same effects can be achieved when 0.5 mm≦P≦1.4 mm, 60 μm≦G≦140 μm, 10 μm≦L 1 , L 2 , L 3 ≦60 μm, 50 μm≦S 1 ≦150 μm, and 40 μm≦S 2 ≦140 μm. 
     Embodiment 3 
     FIG. 6 is a view from above of the display electrodes according to embodiment 3. In contrast to embodiment 2, in which the width of the line part gaps S 1  and S 2  is geometrically reduced, embodiment 3 is characterized in that display electrodes  22  and  23  each include four line parts  22   a  to  22   d  and  23   a  to  23   d , respectively, and the line part gaps S 1  to S 3  decrease arithmetically as the distance from main discharge gap G increases. In the given example, cell pitch P is 1.08 mm, main discharge gap G is 80 μm, line part widths L 1  to L 3  are 40 μm, first line part gap S 1  is 90 μm, second line part gap S 2  is 70 μm, and third line part gap S 3  is 50 μm. 
     In addition to substantially the same effects as embodiment 1, the structure according to embodiment 3 achieves the following. 
     FIG. 7 is a graph showing the relationship between main discharge gap G, an average line part gap S ave , a line part gap differential Δs, and the discharge current peak number according to embodiment 3. As shown in FIG. 7, it is possible to achieve a discharge current waveform having a single peak when the average line part gap S ave  is smaller than main discharge gap G and the differential between each of the line part gaps is at least 10 μm despite of first line part gap S 1  being approximately 10 μm wider than main discharge gap G. 
     In order to compare embodiment 2 (3 line parts) and embodiment 3 (4 line parts), FIG. 8 a  charts power consumption and brightness, and FIG. 8 b  charts sustain voltage and power consumption. The display “on” region in each of the graphs includes an area of approximately 4000 pixels, and the slanted lines in the FIG. 8 a  graph represent the respective efficiencies. As shown in FIG. 8 a , the power-brightness curve of embodiment 3 (4 line parts) overlaps substantially with the power-brightness curve of embodiment 2 (3 line parts). However, the capacity of the PDP according to embodiment 3 is greater than that of embodiment 2, as shown by the fact that the embodiment 3 curve extends beyond the embodiment 2 curve. 
     Furthermore, as shown in FIG. 8 b , under conditions of uniform applied voltage, the four-line structure exhibits a more robust power consumption than the three-line structure. 
     Thus substantially the same brightness levels can be achieved in the PDPs according to both the second and third embodiment under identical power supply conditions. In addition, in embodiment 3, a comparatively lower drive voltage can be achieved, and power loss as well as wear and tear on the circuitry can be reduced with respect to the gas display panel and related panel drive apparatus. 
     Although the various measurements with respect to each of the discharge cells according to embodiment 3 are as given above, the present invention is not limited to these measurements. For example, the same effects can be achieved when 0.5 mm≦P≦1.4 mm, 70 μm≦G≦120 μm, 10 μm≦L 1 , L 2 , L 3 , L 4 ≦60 μm, 80 μm≦S 1 ≦130 μm, 70 μm≦S 2 ≦120 μm, and 60 μm≦S 3 ≦110 μm. 
     Embodiment 4 
     FIG. 9 is a view from above of the display electrodes according to embodiment 4. In this embodiment, display electrodes  22  and  23  each include four line parts  22   a  to  22   d  and  23   a  to  23   d , respectively. Also, line parts  22   c ,  22   b ,  23   c , and  23   b  are wider than line parts  22   a ,  22   b ,  23   a , and  23   b , and line part gaps S 1  to S 3  decrease geometrically as the distance from main discharge gap G increases. In the given example, cell pitch P is 1.08 mm, main discharge gap C is 80 μm, line part widths L 1  and L 2  are 30 μm, line part widths L 3  and L 4  are 40 μm, first line part gap S 1  is 90 μm, second line part gap S 2  is 60 μm, and third line part gap S 3  is 40 μm. 
     In addition to substantially the same effects as embodiment 1, the structure according to embodiment 4 achieves the following. 
     FIG. 10 is a graph showing an exemplary discharge illumination waveform according to embodiment 4. The data in FIG. 10 was gathered by illuminating a single cell of the PDP, attaching an optical fiber avalanche photodiode in order to funnel the light generating from the illuminated cell, and using a digital oscilloscope to measure the illumination waveform at the same time that the drive voltage waveform was measured. The illumination waveform in FIG. 10 shows an average of a thousand test results accumulated using the digital oscilloscope. 
     As shown in FIG. 10, the discharge illumination generated by the drive pulse is completed within a short period (approx. 400 ns) and a steeply sloping peak having a half-width of approximately 200 ns is achieved as a result of the discharge illumination waveform in the PDP of embodiment 4 having a single peak. It is also possible to achieve high-speed driving of approximately 1.25 μs as a result of the discharge delay period (i.e the time taken by the illumination waveform to reach a maximum value after the drive pulse has been applied) being short at 100 ns to 200 ns. These effects can be attributed to (i) a strengthening of the electric field in the vicinity of line parts  22   d  and  23   d  due to the geometrical reduction of line part gaps S 1  to S 3 , thereby facilitating a rapid completion of the discharge, and (ii) the reductions in both the discharge illumination peak half-width and discharge delay dispersion resulting from reductions in formation delays and statistical delays relating to the discharge. 
     Reductions in the discharge probability rate of the address discharge in selected discharge cells during the write period are generally known to cause flicker, graininess, and other deteriorations in image quality in known PDPs. Graininess is increased and flicker occurs when the address discharge probability rate falls below 99.9% and 99%, respectively. It is therefore necessary to keep the failure rate of the address discharge at 0.1% or below. An average discharge delay period of approximately one-third the duration of the write pulse is required in order to achieve this. 
     The NTSC and VGA standards require a definition of approximately 500 scan lines, making it possible to drive the PDP with a write pulse of approximately 2 μs to 3 μs. However, to be compatible with the 1080 scan lines required by standards such as SXGA and full specification high-vision, write pulses of approximately 1 μs to 1.3 μs are necessary in order to drive the PDP. Electrode structures that generate a plurality of discharge illuminations require a substantial amount of time to complete the discharge, thus making it is difficult to meet this level of high definition. 
     In comparison, the single discharge in the PDP using the electrode structure according to embodiment 4 means that the discharge can be completed quickly and with minimum delay, thereby allowing for high driving speeds and high definition to be readily achieved. 
     Although the sustain electrodes according to embodiment 4 include four line parts, the same effect can be achieved by using display electrodes having more than four line parts (e.g. five line parts). 
     Also, while the various measurements with respect to each of the discharge cells according to embodiment 4 are as given above, the present invention is not limited to these measurements. For example, the same effects can be achieved when 0.5 mm≦P≦0.4 mm, 70 μm≦G≦120 μm, 10 μm≦L 1 , L 2 ≦50 μm, 20 μm≦L 3 , L 4 ≦60 μm, 80 μm≦S 1 ≦130 μm, 70 μm≦S 2 ≦120 μm, and 30 μm≦S 3 ≦110 μm. 
     When the width of the line parts L 1  to L 4  are adjusted (this being especially true of the line part L n  positioned furthest from main discharge gap G), it is preferable for the expression L ave ≦L n ≦{0.35P−(L 1 +L 1 + . . . L n−1 )} to be satisfied, where L ave  is an average width of all the line parts in a respective cell. 
     Furthermore, experiment results have shown that, with respect to L 1  and L 2 , it is preferable to satisfy the equations 0.5L ave ≦L 1  and L 2 ≦L ave . 
     It should be noted that the effects of embodiment 4 can still be achieved when the width of the line parts L 1  to L 4  are uniform. 
     Also, while display electrodes  22  and  23  as described above are composed of four line parts  22   a  to  22   d  and  23   a  to  23   d , respectively, it is possible for the display electrodes to include five or more line parts. 
     Embodiment 5 
     FIG. 11 is a view from above of the display electrodes according to embodiment 5. In this embodiment, display electrodes  22  and  23  each include four line parts  22   a  to  22   d  and  23   a  to  23   d , respectively, each of the line parts being of uniform width, and line part gaps S 1  to S 3  become geometrically smaller as the distance from main discharge gap G increases. In the given example, cell pitch P is 1.08 mm, main discharge gap G is 80 μm, line part widths L 1  to L 4  are 40 μm, first line part gap S 1  is 120 μm, second line part gap S 2  is 90 μm, and third line part gap S 3  is 67.5 μm. 
     In addition to substantially the same effects as embodiment 1, the structure according to embodiment 5 achieves the following. 
     FIG. 12 is a graph showing the relationship according to embodiment 5 between (i) a ratio S 1 /G with respect to main discharge gap G and first line part gap S 1 , and (ii) discharge current peak number with respect to a line part gap ratio α=S n+1 /S n . As shown in the FIG. 12 graph, as long as the line part gap ratio α=S n+1 /S n  is 0.8 or below it is possible to achieve a single discharge peak and consequently high driving speeds, even when first line part gap S 1  is 1.5 times main discharge gap G (i.e. S 1 /G equals 1.5). 
     Because the discharge structure according to embodiment 5 allows for a stable sustain discharge having a non-dispersed discharge current peak, it is possible to readily control the gradations by adjusting the pulses. 
     While the various measurements with respect to each of the discharge cells according to embodiment 5 are as given above, the present invention is not limited to these measurements. For example, the same effects can be achieved when 0.5 mm≦P≦1.4 mm, 60 μm≦G≦140 μm, 10 μm≦L 1 , L 2 , L 3 , L 4 ≦60 μm, 50 μm≦S 1 ≦150 μm, 40 μm≦S 2 ≦140 μm, and 30 μm≦S 3 ≦130 μm. 
     Embodiment 6 
     FIG. 13 is a view from above of the display electrodes according to embodiment 6. In this embodiment, display electrodes  22  and  23  each include four line parts  22   a  to  22   d  and  23   a  to  23   d , respectively. Also, line parts  22   d  and  23   d  are wider than the other line parts, and line part gaps S 1  to S 3  are of uniform width. In the given example, cell pitch P is 1.08 mm, main discharge gap G is 80 μm, line part widths L 1  to L 3  are 40 μm, line part width L 3  is 80 μm, and line part gaps S 1  to S 3  are 70 μm. 
     In addition to substantially the same effects as embodiment 1, the structure according to embodiment 6 achieves the following. 
     FIG. 14 is a waveform diagram showing the change over time of the drive voltage waveform and the discharge current waveform in the PDP according to embodiment 6. As shown in FIG. 14, the discharge current waveform having a single peak makes it possible for the illumination discharge generated by a single drive pulse to be completed within 1 μs and for the discharge delay period to be kept short at approximately 0.2 μs. It is thus possible to achieve high driving speeds of 2 μs to 3 μs. 
     Table 1 below, shows the change in the line part resistance value, minimum address voltage V dmin , and the number of peaks of the discharge current waveform when width L 4  of line parts  22   d  and  23   d  are varied in the PDP as per embodiment 6. 
     
       
         
           
               
               
             
               
                   
                 TABLE 1 
               
             
            
               
                   
                   
               
               
                   
                 L 4  [μm] 
               
            
           
           
               
               
               
               
               
               
            
               
                   
                 40 
                 50 
                 70 
                 90 
                 110 
               
               
                   
                   
               
            
           
           
               
               
               
               
               
               
            
               
                 line part 22d, 23d resistance 
                 56 
                 53 
                 47 
                 43 
                 39 
               
               
                 value [Ω] 
               
               
                 minimum applied voltage [V] 
                 58 
                 55 
                 49 
                 44 
                 40 
               
               
                 discharge current waveform peak no. 
                 1 
                 1 
                 1 
                 1 
                 1 
               
               
                   
               
            
           
         
       
     
     As shown in table 1, by widening L 4  and thereby reducing the line part resistance value, while at the same time maintaining a single-peaked discharge current, it is possible to reduce the applied voltage required to conduct the addressing in the write period. 
     While the various measurements with respect to each of the discharge cells according to embodiment 6 are as given above, the present invention is not limited to these measurements. For example, the same effects can be achieved when 0.5 mm≦P≦1.4 mm, 60 μm≦G≦140 μm, 10 μm≦L 1 , L 2 , L 3 , L 4 ≦60 μm, L 1 ≦L4≦3×L 1 , and 50 μm≦S≦140 μm. 
     Embodiment 7 
     FIG. 15 is a view from above of the display electrodes according to embodiment 7. In this embodiment, display electrodes  22  and  23  each include four line parts  22   a  to  22   d  and  23   a  to  23   d , respectively. Also, line part  22   c ,  22   d ,  23   c , and  23   d  are wider than the other line parts, and line part gaps S 1  to S 3  decrease in width as the distance from main discharge gap G increases. In the given example, cell pitch P is 1.08 mm, main discharge gap G is 80 μm, line part widths L 1  and L 2  are 30 μm, line part widths L 3  and L 4  are 40 μm, first line part gap S 1  is 90 μm, second line part gap S 2  is 70 μm, and third line part gap S 3  is 50 μm. 
     In addition to substantially the same effects as embodiment 1, the structure according to embodiment 7 achieves the following. 
     FIG. 16 is a graph showing the relationship between power consumption and brightness in the PDP according to embodiments 6 and 7. Generally in a PDP, panel brightness is proportionate to the amount of power supplied, although in FIG. 16 the power-brightness curves are tending towards saturation. Increasing the supply of power will consequently lead to a drop in luminous efficiency. 
     As shown in FIG. 16, embodiment 7 is able to achieve higher brightness levels and superior luminous efficiency under identical power supply conditions in comparison to embodiment 6. 
     While the various measurements with respect to each of the discharge cells according to embodiment 7 are as given above, the present invention is not limited to these measurements. For example, the same effects can be achieved when 0.5 mm≦P≦1.4 mm, 60 μm≦G≦140 μm, 10 μm≦L 1 , L 2 ≦60 μm, 20 μm≦L 3 , L 4 ≦70 μm, 50 μm≦S 1 ≦150 μm, 40 μm≦S 2 ≦140 μm, and 30 μm≦S 3 ≦130 μm. 
     Embodiment 8 
     FIG. 17 is a view from above of the display electrodes according to embodiment 8. In this embodiment, display electrodes  22  and  23  each include four line parts  22   a  to  22   d  and  23   a  to  23   d , respectively. Also, line part  22   c ,  22   d ,  23   c , and  23   d  are wider than the other line parts, and line part gaps S 1  to S 3  decrease in width as the distance from main discharge gap G increases. Furthermore, in order to improve the quality of the display screen, a black layer (not shown in the diagram) composed of a black material such as ruthenium oxide is provided in between the display electrodes and front panel glass  21  so as to correspond with the positioning of the display electrodes. 
     In the given example, cell pitch P is 1.08 mm, main discharge gap G is 80 μm, line part widths L 1  and L 2  are 35 μm, line part width L 3  is 45 μm, line part width L 4  is 85 μm, first line part gap S 1  is 90 μm, second line part gap S 2  is 70 μm, and third line part gap S 3  is 50 μm. 
     In addition to substantially the same effects as embodiment 1, the structure according to embodiment 8 achieves the following. 
     FIG. 18 is a graph showing the relationship between blackness and photopic contrast when L 4  is varied in the PDP according to embodiment 8. The photopic contrast axis in FIG. 18 is a measure of a black display/white display brightness ratio with respect to the display surface of the PDP, given a vertical illuminance of 70Lx and a horizontal illuminance of 150Lx. 
     Generally in a PDP, the contrast ratio under photopic conditions is in a range of approximately 20:1 to 50:1 given the high reflectivity of the panel display surface due to the phosphor layers and barrier rib walls being white. According to embodiment 8, however, it is possible to achieve an extremely high photopic contrast ratio of approximately 70:1 due to the combined effects of the black layer and the securing of the discharge gained as a result of increasing the width L 4 . 
     Although further increases in photopic contrast can be achieved by increasing the blackness ratio and the value of width L 4 , the cell aperture ratio decreases and brightness levels fall when the blackness ratio is over increased (brightness decreases by approximately 10% at a blackness ratio of 50%). Thus it is preferable to maintain the blackness ratio within 60%. 
     While the various measurements with respect to each of the discharge cells according to embodiment 8 are as given above, the present invention is not limited to these measurements. For example, the same effects can be achieved when 0.5 mm≦P≦1.4 mm, 60 μm≦G≦140 μm, 10 μm≦L 1 , L 2 ≦60 μm, 20 μm≦L 3 ≦70 μm, 20 μm≦L 4 ≦0.3P−(L 1 +L 2 +L 3 )μm, 50 μm≦S 1 ≦150 μm, 40 μm≦S 2 ≦140 μm, and 30 μm≦S 3 ≦130 μm. 
     Also, it is possible for the black material used for the black layer to include a metal oxide such as nickel, chromium, or iron. 
     Embodiment 9 
     9-1 Structure of the Display Electrodes 
     FIG. 19 is a view from above of the display electrodes according to embodiment 9. In this embodiment, display electrodes  22  and  23  each include four line parts  22   a  to  22   d  and  23   a  to  23   d , respectively, line parts  22   d  and  23   d  being wider than the other line parts, and line part gaps S 1  to S 3  decreasing in width in the stated order. Embodiment 9 is characterized in that short-bars  22 Sb 1  to  22 Sb 3  and  23 Sb 1  to  23 Sb 3  are randomly provided so as to electrically connect adjacent line parts. In the given example the short-bars are band-shaped bars extending in the y direction, although other formations of the short-bars are possible. 
     In the given example, cell pitch P is 1. 08 mm, main discharge gap G is 80 μm, line part widths L 1  and L 2  are 35 μm, line part width L 3  is 45 μm, line part width L 4  is 85 μm, first line part gap S 1  is 90 μm, second line part gap S 2  is 50 μm, third line part gap S 3  is 50 μm, and short-bar width W sb  is 40 μm. 
     9-2 Effects of Embodiment 9 
     In addition to substantially the same effects as embodiment 1, the structure according to embodiment 9 achieves the following. 
     Table 2 shows data relating to a capacity of the PDP according to embodiment 9. In the given example, the capacity was measured at L 4  values of 50 μm and 85 μm. “Open circuit repairability” in table 2 shows the possibility of repairing line parts  22   d  and  23   d  when an open circuit occurs (“◯” “Δ” “X” show the possibility of repair in order of increasing difficulty). 
     
       
         
           
               
               
             
               
                   
                 TABLE 2 
               
             
            
               
                   
                   
               
               
                   
                 L 4  [μm] 
               
            
           
           
               
               
               
               
               
               
            
               
                   
                 50 
                 50 
                 50 
                 85 
                 85 
               
               
                   
                   
               
            
           
           
               
               
               
               
               
               
            
               
                 Short-bar 
                 no 
                 yes 
                 yes 
                 yes 
                 yes 
               
               
                 short-bar gap [cm] 
                 — 
                 8 
                 random 
                 random 
                 random 
               
               
                 open circuit prob. [freq./line] 
                 0.15 
                 0.004 
                 0.002 
                 0 
                 0 
               
               
                 line part resistance value [Ω] 
                 67 
                 53 
                 47 
                 44 
                 44 
               
               
                 open circuit repairability 
                 X  
                 Δ 
                 Δ 
                 ◯ 
                 ◯ 
               
               
                   
               
            
           
         
       
     
     As shown in table 2, providing short-bars proves extremely effective, as the line part resistance value is lowered and the probability of an open circuit occurring is reduced from 15% to 0.4% in comparison to when short-bars are not provided. Thus by providing short-bars randomly between the line parts, embodiment 9 makes it possible to achieve an excellent display capacity in which the occurrence of moiré can be suppressed. 
     While the various measurements with respect to each of the discharge cells according to embodiment 5 are as given above, the present invention is not limited to these measurements. For example, the same effects can be achieved when 0.5 mm≦P≦1.4 mm, 60 μm≦G≦140 μm, 10 μm≦L 1 , L 2 ≦60 μm, 20 μm≦L 3 ≦70 μm, 40 μm≦L 4 ≦0.3P−(L 1 +L 2 +L 3 ) μm, 50 μm≦S 1 ≦150 μm, 40 μm≦S 2 ≦140 μm, 30 μm≦S 3 ≦130 μm, and 10 μm≦W sb ≦80 μm. 
     Embodiment 10 
     FIG. 20 is a cross-sectional view along a Y—Y axis of a section of the PDP according to embodiment 10 (in FIG. 20, barrier rib  30  forms the inner wall of discharge space  38 ). Although the arrangement of the display electrodes is the same as in embodiment 9, embodiment 10 is characterized by the provision of auxiliary barrier ribs  34  (second barrier ribs) that are positioned on the outer side of line parts  22   d  and  23   d , respectively (i.e. the opposite side to the side facing main discharge gap G), so as to extend in a lengthwise direction of the line parts. In other words, auxiliary barrier ribs  34  are positioned orthogonally to and form a matrix with barrier ribs  30  (first barrier ribs) and partition off each pair of discharge electrodes  22  and  23 . 
     In the given example, cell pitch P is 1.08 mm, main discharge gap G is 80 μm, line part widths L 1  and L 2  are 35 μm, line part width L 3  is 45 μm, line part width L 4  is 85 μm,s first line part gap S 1  is 90 μm, second line part gap S 2  is 50 μm, third line part gap S 3  is 50 μm, short-bar width W sb  is 40 μm, barrier rib height H is 110 μm, auxiliary barrier rib high h is 60 μm, auxiliary barrier rib width (top) Wait is 60 μm, and auxiliary barrier rib width (bottom) W alb  is 100 μm. 
     Additional to the effects of embodiment 9, the structure according to embodiment 10 achieves the following. 
     Table 3 shows data relating to the occurrence of crosstalk-generated erroneous discharge in the PDP according to embodiment 10, given Ipg values (i.e. the distance between line part  22   d  in one cell and line part  23   d  in a cell adjacent in they direction) ranging from 60 μm to 360 μm, and depending on the provision or non-provision of the auxiliary barrier ribs. 
     
       
         
           
               
               
             
               
                   
                 TABLE 3 
               
             
            
               
                   
                   
               
               
                   
                 I pg  [μm] 
               
            
           
           
               
               
               
               
               
               
               
               
               
            
               
                   
                 60 
                 120 
                 260 
                 260 
                 300 
                 300 
                 360 
                 360 
               
               
                   
                   
               
            
           
           
               
               
               
               
               
               
               
               
               
            
               
                 auxiliary barrier 
                 yes 
                 yes 
                 no 
                 yes 
                 no 
                 yes 
                 no 
                 yes 
               
               
                 ribs 
               
               
                 crosstalk/ 
                 X 
                 ◯ 
                 X 
                 ◯ 
                 X 
                 ◯ 
                 ◯ 
                 ◯ 
               
               
                 erroneous 
               
               
                 discharge 
               
               
                   
               
            
           
         
       
     
     As shown in table 3, crosstalk-generated erroneous discharge is likely to occur at Ipg values of approximately 300 μm and below when auxiliary barrier ribs  34  are not provided. Graininess and flicker will result from this erroneous discharge when the PDP is driven. In contrast, according to embodiment 10, crosstalk-related erroneous discharge does not occur and an excellent display capacity can be achieved when auxiliary barrier ribs  34  are provided, even at Ipg values of approximately 120 μm. In other words, the provision of auxiliary barrier ribs  34  helps to suppress the diffusion from the perimeter of discharge cells into adjacent cells of (i) priming particles (i.e. charge particles, etc) generated by discharge plasma and (ii) resonance lines within the vacuum ultraviolet region. 
     Although the suppression of crosstalk can be further enhanced by increasing the height h (see FIG. 20) of auxiliary barrier ribs  34 , it becomes difficult to adequately deaerate the discharge space  38  and fill it with discharge gas during manufacture when the height h approximates too closely the height H of barrier ribs  30 . It is therefore preferable for the height h of the auxiliary barrier ribs  30  to be shorter than the height H of barrier ribs  30  by at least 10 μm. Specifically, it is preferable for the height h to be in a range of 50 μm to 120 μm inclusive. 
     Furthermore, it is preferable for a top width Wait and a bottom width W alb  of auxiliary barrier ribs  34  to be in a range of 30 μm to 300 μm inclusive due to reductions in the magnitude of the discharge when the top width W alt  and bottom width W alb  are too wide. 
     Also, while the various measurements with respect to each of the discharge cells according to embodiment 10 are as given above, the present invention is not limited to these measurements. For example, the same effects can be achieved when 0.5 mm≦P≦1.4 mm, 60 μm≦G≦140 μm, 10 μm≦L 1 , L 2 ≦60 μm, 20 μm≦L 3 ≦70 μm, 20 μm≦L 4 ≦0.3P−(L 1 +L 2 +L 3 ) μm, 50 μm≦S 1 ≦150 μm, 40 μm≦S 2 ≦140 μm, 30 μm≦S 3 ≦130 μm, 10 μm≦W sb ≦80 μm, 50 μm≦W alt ≦450 μm, and 60 μm≦h≦H−10 μm. 
     It is also possible for auxiliary barrier ribs  34  to be adapted for inclusion in the other embodiments of the present invention. 
     Embodiment 11 
     11-1 Structure of the Display Electrodes 
     FIG. 21 is a view from above of the display electrodes according to embodiment 11. In this embodiment, display electrodes  22  and  23  each include four line parts  22   a  to  22   d  and  23   a  to  23   d , respectively, line parts  22   d  and  23   d  being wider than the other line parts, and line part gaps S 1  to S 3  being of uniform width. Embodiment 11 is characterized by the provision of short-bars  22 Sbg and  23 Sbg in the green discharge cell (G cell) so as to electrically connect each of the line parts  22   a  to  22   d  and  23   a  to  23   d , respectively. 
     In the given example, cell pitch P is 1.08 mm, main discharge gap G is 80 μm, line part widths L 1  to L 3  are 35 μm, line part width L 4  is 80 μm, line part gap S (S 1  to S 3 ) is 70 μm, and short-bar width W sb  is 40 μm. 
     11-2 Effects of Embodiment 11 
     In addition to substantially the same effects as embodiment 1, the structure according to embodiment 11 achieves the following. 
     FIG. 22 is a waveform diagram showing the change over time of the drive voltage waveform and the discharge current waveform in the PDP according to embodiment 11. As shown in FIG. 22, because of the discharge current waveform having a single peak according to embodiment 11, it is possible to complete the discharge illumination generating from a single drive pulse within 1 μs and to achieve a short discharge delay period of approximately 0.2 μs. High driving speeds of 2 μs to 3 μs can be achieved as a result. 
     The data in table 4 shows the way in which the minimum sustain voltage V susmin  in each of the cells R, G, B varies depending on the provision or non-provision of short-bars in the PDP according to embodiment 11. 
     
       
         
           
               
               
             
               
                   
                 TABLE 4 
               
             
            
               
                   
                   
               
               
                   
                 discharge cell 
               
            
           
           
               
               
               
               
               
            
               
                   
                 R 
                 G 
                 B 
                 G 
               
               
                   
                   
               
            
           
           
               
               
               
               
               
            
               
                 short-bar 
                 no 
                 no 
                 no 
                 yes 
               
               
                 Vsusmin [V] 
                 167 
                 175 
                 165 
                 165 
               
               
                 discharge current waveform peak no. 
                 1 
                 1 
                 1 
                 1 
               
               
                   
               
            
           
         
       
     
     As shown in table 4, the minimum sustain voltage V susmin  in each of the cells R, G, B is dispersed when short-bars are not provided in the cells. Because the minimum applied voltage (i.e. set value) of the entire panel is set to be equal to or greater than the V susmin  of the G cell (i.e. the cell having the highest V susmin  value in table 4), the lower limit of the drive margin is raised when V susmin  is different for each of the cells. The set margin of the drive voltage is narrowed as a result. 
     In contrast, according to embodiment 11, it is possible to reduce V susmin  by approximately 10V when short-bars  22 Sbg and  23 Sbg are provided in the G cell. The V susmin  value differential between each of the cells R, G, B is thus reduced, and the drive voltage margin is expanded due to a reduction in the set value of the applied voltage. This effect can be attributed to the increased surface area of display electrodes  22  and  23  in the G cell resulting from the provision of the short-bars, thus allowing for an increase in the amount of stored wall charge and a consequent reduction in the discharge initiating voltage in the G cell While the various measurements with respect to each of the discharge cells according to embodiment 5 are as given above, the present invention is not limited to these measurements. For example, the same effects can be achieved when 0.5 mm≦P≦1.4 mm, 60 μm≦G≦140 μm, 10 μm≦L 1 , L 2 , L 3 ≦60 μm, L 1 ≦L 4 ≦3L 1 , 50 μm≦S≦140 μm, and 10 μm≦W sb ≦100 μm. 
     Embodiment 12 
     FIG. 23 is a view from above of the display electrodes according to embodiment 12. In this embodiment, display electrodes  22  and  23  each include four line parts  22   a  to  22   d  and  23   a  to  23   d , respectively, line parts  22   d  and  23   d  being wider than the other line parts, and line part gaps S 1  to S 3  decreasing in width as the distance from the main discharge gap increases. Embodiment 12 is characterized by the provision of short-bars  22 Sbr and  23 Sbr in the red discharge cell (R cell) and short-bars  22 Sbg and  23 Sbg in the green discharge cell (G cell), the short-bars electrically connecting the line parts  22   a  to  22   d  and  23   a  to  23   d , respectively. 
     In the given example, cell pitch P is 1.08 mm, main discharge gap G is 80 μm, line part widths L 1  to L 3  are 40 μm, line part width L 4  is 80 μm, first line part gap S 1  is 90 μm, second line part gap S 2  is 70 μm, third line part gap S 3  is 50 μm, and short-bar width W sb  is 40 μm. 
     In addition to improvements in luminous efficiency, the structure according to embodiment 12 achieves the following. 
     Generally, in a PDP the discharge delay periods of the address discharges occurring in the write period is not uniform for each of the cells R, G, B because of differences in the statistical delay periods Ts in the respective cells. In particular, the high Ts value of the R cell and G cell implies that writing failure is more likely to occur given the comparatively low address discharge probability rates in these cells. This result will be flicker and other reductions in image quality when the PDP is driven. 
     One particular method of improving the discharge probability rate during the write period is to increase the voltage of the write pulse. However, this adversely increases the power consumption of the data driver circuit, and consequently increases in the overall power usage of the PDP. 
     In contrast, embodiment 12 is able to overcome the problem of a low discharge probability rate in addition to improving luminous efficiency. Specifically, reductions in the Ts value are made possible by increasing the surface area of the display electrode in the R cell and G cell through the provision of the short-bars, thereby increasing the capacitance in these cells. The discharge probability rate of the address discharge is improved by approximately 1.0% as a result, and flicker and other reductions in image quality caused by failed addressing are reduced in comparison to existing technology. Also, the excellent display capacity in the PDP according to embodiment 12 makes it possible to expand the drive voltage margin, even at address discharge voltages V data  lower than existing values. 
     Table 5 shows the way in which the statistical delay periods Ts in each of the cells R, G, B vary depending on the provision or non-provision of short-bars in the PDP according to embodiment 12. 
     
       
         
           
               
               
             
               
                   
                 TABLE 5 
               
             
            
               
                   
                   
               
               
                   
                 discharge cell 
               
            
           
           
               
               
               
               
               
               
            
               
                   
                 R 
                 G 
                 B 
                 R 
                 G 
               
               
                   
                   
               
            
           
           
               
               
               
               
               
               
            
               
                 short-bar 
                 no 
                 no 
                 no 
                 yes 
                 yes 
               
               
                 statistical delay period [μs] 
                 0.15 
                 0.20 
                 0.10 
                 0.10 
                 0.13 
               
               
                 address discharge probability [%] 
                 99.0 
                 98.0 
                 99.9 
                 99.8 
                 99.5 
               
               
                   
               
            
           
         
       
     
     As shown in table 5, dispersion in the statistical delay periods Ts between each of the cells R, G, B in a PDP that does not include short-bars means that the discharge delay periods of the address discharges during the write period will be different for each of the cells. 
     In comparison, in a PDP having an electrode structure as per embodiment 12, it is possible to reduce the differences in the discharge probability rate and achieve an excellent display capacity by reducing the statistical delay period in the R cell and G cell through the provision of the short-bars in these cells. 
     While the various measurements with respect to each of the discharge cells according to embodiment 5 are as given above, the present invention is not limited to these measurements. For example, the same effects can be achieved when 0.5 mm≦P≦1.4 mm, 60 μm≦G≦140 μm, 10 μm≦L 1 , L 2 , L 3 ≦60 m, L 1 ≦L 4 ≦3L 1 , 50 μm≦S 1 ≦150 μm, 40 μm≦S 2 ≦140 μm, 30 μm≦S 3≦130  μm, and 10 μm≦W sb ≦100 μm. 
     Embodiment 13 
     FIG. 24 is a view from above of the display electrodes according to embodiment 13. In comparison to embodiment 12, short-bars  22   sbb  and  23   sbb  are provided only in the blue discharge cell (B cell) in the PDP according to embodiment 13. In the given example, cell pitch P is 1.08 mm, main discharge gap G is 80 μm, line part widths L, to L 3  are 40 μm, line part width L 4  is 80 μm, first line part gap S 1  is 90 μm, second line part gap S 2  is 70 μm, third line part gap S 3  is 50 μm, and short-bar width W sb  is 40 μm. 
     In addition to improvements in luminous efficiency, the structure according to embodiment 13 achieves the following. 
     In prior art PDPs it is generally difficult to balance the brightness of each of the cells R, G, B, thus makes it possible to only achieve panel color temperatures of approximately 5000K to 7000K. One method of improving the color temperature to around 11000K is to correct the whiteness balance by reducing the brightness of the R cell and G cell when the PDP is driven, thereby approximating the brightness and chromaticity of the B cell. However, this method adversely reduces the overall brightness of the display. 
     In contrast, embodiment 13 is able to overcome the problem of low brightness in the B cell in addition to improving luminous efficiency. Specifically, it is possible to improve the relative brightness of the B cell with respect to the R cell and G cell by increasing the surface area of the display electrodes in the B cell through the provision of short-bars  22   sbb  and  23   sbb . The result is an increase in panel color temperature without any necessary reduction in the overall brightness of the display as is the case in prior art PDPs. 
     Table 6 shows the way in which color temperature varies during the whiteness display period depending on the provision or non-provision of short-bars in a PDP according to embodiment 13. 
     
       
         
           
               
               
               
             
               
                   
                 TABLE 6 
               
             
            
               
                   
                   
               
               
                   
                 B cell short-bar 
                   
               
            
           
           
               
               
               
            
               
                   
                 No 
                 yes 
               
               
                   
                   
               
            
           
           
               
               
               
               
            
               
                   
                 white brightness [cd/m 2 ] 
                 360 
                 380 
               
               
                   
                 color temp. [K] 
                 5000-7000 
                 9500-13000 
               
               
                   
                   
               
            
           
         
       
     
     As shown in table 6, it is possible to achieve an extremely high color temperature of 9500K to 13000K in the PDP according to embodiment 13 when short-bars  22   sbb  and  23   sbb  are provided in the B cell. 
     While the various measurements with respect to each of the discharge cells according to embodiment 5 are as given above, the present invention is not limited to these measurements. For example, the same effects can be achieved when 0.5 mm≦P≦1.4 mm, 60 μm≦G≦140 μm, 10 μm≦L 1 , L 2 , L 3 ≦60 μm, L 1 ≦L 4 ≦3L 1 , 50 μm≦S 1 ≦150 μm, 40 μm&#39;S 2 ≦140 μm, 30 μm≦S 3  ≦130 μm, and 10 μm≦W sb ≦100 μm. 
     Embodiment 14 
     FIG. 25 is a view from above of the display electrodes according to embodiment 14. In comparison to embodiment 12, short-bars  22   sb  are provided only on scan electrode  22  in the PDP according to embodiment 13. In the given example, cell pitch P is 1.08 mm, main discharge gap G is 80 μm, line part widths L 1  to L 3  are 40 μm, line part width L 4  is 80 μm, first line part gap S 1  is 90 μm, second line part gap S 2  is 70 μm, third line part gap S 3  is 50 μm, and short-bar width W ob  is 40 μm. 
     It is possible for short-bars  22   sb  to be provided on scan electrode  22  in any of the cells R, G, B. According to embodiment 14, short-bars  22   sb  are provided in all of the cells. 
     In addition to improvements in luminous efficiency, the structure according to embodiment 14 achieves the following. 
     Generally, in order to uniformize the wall charge in all of the discharge cells in the panel of a PDP, it is necessary to conduct one or more set-up discharges in at least one field prior to the write period in which specific pixels will be selected for illumination. Since all the cells in the panel are illuminated simultaneously during the set-up period (i.e. set-up illumination), it is not possible to reproduce precisely any particular color even black (i.e. because of some cells remaining illuminated) when the PDP is driven, thereby leading to an unsatisfactory contrast ratio. As a result, contrast ratios of only approximately 500:1 have been achieved in prior art PDPs. 
     In contrast, by providing short-bars  22   sb  on scan electrode  22  according to embodiment 14 it is possible to increase the surface area of scan electrode  22  and thus increase the storage of wall charge on scan electrode  22 . Reductions in the discharge initiating voltage result from the increase in wall voltage, thereby making it possible to reduce the power supply to the panel during the set-up discharge period and achieve an excellent display capacity due to the resultant improvements in contrast. 
     Table 7 shows the way in which the set-up voltage V set  and contrast vary depending on the provision or non-provision of short-bars in the PDP according to embodiment 14. 
     
       
         
           
               
               
               
             
               
                   
                 TABLE 7 
               
             
            
               
                   
                   
               
               
                   
                 scan elect. short-bar 
                   
               
            
           
           
               
               
               
            
               
                   
                 No 
                 yes 
               
               
                   
                   
               
            
           
           
               
               
               
               
            
               
                   
                 Vset [V] 
                 390 
                 370 
               
               
                   
                 contrast ratio 
                 500:1 
                 1000:1 
               
               
                   
                   
               
            
           
         
       
     
     As shown in table 7, V set  is reduced when short-bars are provided on the scan electrode in comparison to when they are not (i.e. embodiment 14). Further, contrast is improved two-fold by providing the short-bars in this manner. 
     While the various measurements with respect to each of the discharge cells according to embodiment 5 are as given above, the present invention is not limited to these measurements. For example, the same effects can be achieved when 0.5 mm≦P≦1.4 mm, 60 μm≦G≦140 μm, 10 μm≦L 1 , L 2 , L 3 ≦60 μm, L 1 ≦L 4 ≦3L 1 , 50 μm≦S 1 150 μm, 40 μm≦S 2 ≦140 μm, 30 μm≦S 3  ≦130 μm, and 10 μm≦W sb ≦100 μm. 
     Embodiment 15 
     FIG. 26 is a view from above of the display electrodes according to embodiment 15. In comparison to embodiment 14, short-bars  22   sb  are provided only on a central part of scan electrode  22  (i.e. so as to connect line parts  22   b  and  22   c ) in the PDP according to embodiment 15. In the given example, cell pitch P is 1.08 mm, main discharge gap G is 80 μm, line part widths L 1  to L 3  are 40 μm, line part width L 4  is 80 μm, first line part gap S 1  is 90 μm, second line part gap S 2  is 70 μm, third line part gap S 3  is 50 μm, and short-bar width W sb  is 40 μm. 
     In addition to substantially the same effects as embodiment 14, the structure according to embodiment 15 achieves the following. 
     Specifically, by providing short-bars  22   sb  in the central part of scan electrode  22 , it is possible to achieve a relatively wide electrode surface area while at the same time maintaining the cell aperture ratio in the vicinity of main discharge gap G, which is the area where the illumination brightness distribution in the cell is highest. As a result, it is possible to achieve excellent panel brightness from a simple display electrode structure consisting of a plurality of lines. 
     Table 8 shows the way in which the data voltage V data  varies depending on the provision or non-provision of short-bars in the PDP according to embodiment 15. 
     
       
         
           
               
               
             
               
                   
                 TABLE 8 
               
             
            
               
                   
                   
               
               
                   
                 discharge cell 
               
            
           
           
               
               
               
               
               
               
               
            
               
                   
                 R 
                 G 
                 B 
                 R 
                 G 
                 B 
               
               
                   
                   
               
            
           
           
               
               
               
               
               
               
               
               
            
               
                   
                 short-bar 
                 no 
                 no 
                 no 
                 yes 
                 yes 
                 yes 
               
               
                   
                 Vdatamin [V] 
                 54 
                 56 
                 50 
                 42 
                 44 
                 40 
               
               
                   
                   
               
            
           
         
       
     
     As shown in table 8, it is possible to reduce the set-up voltage V set  in cells in which short-bars  22   sb  have been provided. 
     Generally, a start-up velocity of approximately 200V/μs to 400V/μs is required in order to apply the address discharge voltage when a PDP is driven. A reactive power W Ld  generating from the address discharge is expressed as: 
     
       
         W Ld =Cp V data   2  f 
       
     
     (V data : address discharge voltage; Cp: panel capacitance; f: write frequency) 
     Reactive power W Ld  thus equals data voltage V data  squared. According to embodiment 15, it is therefore possible to reduce the address discharge voltage by 20% in comparison to existing levels, and ultimately, to reduce reactive power W Ld  by approximately 36% in comparison to existing levels. 
     While the various measurements with respect to each of the discharge cells according to embodiment 5 are as given above, the present invention is not limited to these measurements. For example, the same effects can be achieved when 0.5 mm≦P≦1.4 mm, 60 μm≦G≦140 μm, 10 μm≦L 1 , L 2 , L 3 ≦60 μm, L 1 ≦L 4 ≦3L 1 , 50 μm≦S 1 ≦150 μm, 40 μm≦S 2 ≦140 μm, 30 μm≦S 3 ≦130 μm, and 10 μm≦W sb ≦100 μm. 
     Although short-bars  22   sb  according to embodiment 15 are provided in a central part of scan electrode  22  (i.e. between line parts  22   b  and  22   c ), it is possible to provide the short-bars in other structures, such as between line parts  22   c  and  22   d , for instance. 
     Embodiment 16 
     FIG. 27 is a view from above of the display electrodes according to embodiment 16. In comparison to embodiment 15, short-bars  22   sb  are provided only between the line parts  22   a  and  22   b  of scan electrodes  22 . In the given example, cell pitch P is 1.08 mm, main discharge gap G is 80 μm, line part widths L 1  to L 3  are 40 μm, line part width L 4  is 80 μm, first line part gap S 1  is 90 μm, second line part gap S 2  is 70 μm, third line part gap S 3  is 50 μm, and short-bar width W sb  is 40 μm. 
     In addition to substantially the same effects as embodiment 14, the structure according to embodiment 16 achieves the following. 
     Specifically, by providing short-bars  22   sb  so as to connect line parts  22   a  and  22   b , it is possible to increase the amount of wall charge and the wall voltage in the vicinity of main discharge gap G, thereby making it easier to generate the set-up discharge and the address discharge due to the resultant reductions in V set  and V data . Furthermore, because of the amelioration of set-up discharge failure and address discharge failure as a result of the reductions in V set  and V data , the drive margin is widened and V sus  is reduced. Thus it is possible to suppress power consumption is a favorable manner. 
     Table 5 shows the way in which V set , V sus , and V data  vary depending on the provision or non-provision of short-bars in the PDP according to embodiment 16. 
     
       
         
           
               
               
               
             
               
                   
                 TABLE 9 
               
             
            
               
                   
                   
               
               
                   
                 short-bar 
                   
               
            
           
           
               
               
               
            
               
                   
                 no 
                 yes 
               
               
                   
                   
               
            
           
           
               
               
               
               
            
               
                   
                 Vset [V] 
                 390 
                 370 
               
               
                   
                 Vsus [V] 
                 185 
                 175 
               
               
                   
                 Vdata [V] 
                 65 
                 55 
               
               
                   
                   
               
            
           
         
       
     
     As shown in table 9, it is possible to reduce V set , V sus , and V data , and therefore the drive voltage, when short-bars are provided on the scan electrode near the main discharge gap, in comparison to when short-bars are not provided. 
     While the various measurements with respect to each of the discharge cells according to embodiment 5 are as given above, the present invention is not limited to these measurements. For example, the same effects can be achieved when 0.5 mm≦P≦1.4 mm, 60 μm≦G≦140 μm, 10 μm≦L 1 , L 2 , L 3 ≦60 μm, L 1 ≦L 4 ≦3L 1 , 50 μm≦S 1 ≦150 μm, 40 μm≦S 2 ≦140 μm, 30 μm≦S 3 ≦130 μm, and 10 μm≦W sb ≦100 μm. 
     Also, in embodiment 16, it is preferable to provide short-bars  22   sb  in all of the cells R, G, B, and to arrange the widths of the various short-bars SbR, SbG, and SbB such that SbR≦SbG≦SbB. That is, by increasing the surface area of the R cell and G cell in comparison to the B cell, it is possible reduce (i) the statistical delay period Ts during the address discharge and (ii) the discharge delay differential between each of the cells R, G, B. 
     Embodiment 17 
     17-1 Structure of the Display Electrodes 
     FIG. 28 is a view from above of the display electrodes according to embodiment 17. The electrode structure in the PDP according to embodiment 17 is very different to that of embodiments 1 to 16. Specifically, display electrode  22  ( 23 ) is composed of line part  221  ( 231 ) and inner protrusion part  222  ( 232 ), which is electrically connected to the edge of part  221  ( 231 ) facing main discharge gap G. Inner protrusion parts  222  and  232  are each formed as a trapezium with the central area removed, the top end of each trapezium lying parallel to the other. In the given example, cell pitch P is 1.08 mm, the barrier rib pitch is ⅓ of cell pitch P. electrode length L is 0.37 mm, and W f  is 220 μm. Also, in order to reduce the line resistance of display electrodes  22  and  23 , inner protrusion part width W 2 ≦line part width W 1 . 
     This structure of the display electrodes allows for a single-peaked discharge current waveform and excellent luminous efficiency when the PDP is driven. 
     17-2 Effects of Embodiment 17 
     The above structure allows for substantially the same effects as embodiment 1. In other words, owing to the relatively thin protrusion parts  222  and  232 , it is possible to initiate a discharge between parts  222  and  232  with little capacitance, and to subsequently expand the magnitude of the discharge to the gap between line parts  221  and  231 . It thus becomes possible to achieve excellent power reductions as a result of being able to suppress the discharge initiating voltage. 
     In addition, it is possible for the discharge illumination generated by a single drive pulse to be completed in 1 μm because of the discharge current waveform generated by display electrodes  22  and  23  having a single peak. Also, because the discharge delay period is short at approximately 0.2 μs, a high driving speed of a few μs and a high image quality can be achieved. 
     FIG. 29 is a graph showing the relationship between the surface area of the display electrodes and brightness when W 1 =W 2  in the PDP according to embodiment 17. As shown in FIG. 29, at electrode widths of 40 μm and below, brightness levels fall as a result of the decrease in discharge current related to the reduced electrode surface area. Brightness levels also begin to fall at electrode widths of 80 μm and greater as a result of the decrease in the cell aperture rate related to the enlarged electrode surface area. Thus, panel brightness is optimized at electrode widths (i.e. the respective widths of the fine parts and the inner protrusion parts) of 40 μm to 80 μm. Luminous efficiency, on the other hand, is shown by the slope of the unevenly-broken straight line in FIG.  29 . As shown in FIG. 29, luminous efficiency is optimized at narrower electrode widths. Thus, in the actual manufacture of the PDP, it is preferable for the electrode widths to be such that 40 μm≦W 1 ≦80 μm and 10 μm≦W 2 ≦40 μm. 
     While the various measurements with respect to each of the discharge cells according to embodiment 17 are as given above, the present invention is not limited to these measurements. For example, the same effects can be achieved when 0.9 mm≦P≦0.4 mm, 0.05 mm≦L&lt;0.4 mm, and 0.08 mm≦W f ≦0.4 mm. 
     Additionally, it is preferable to arrange protrusion parts  222  and  232  so that their perimeter edges in the y direction are positioned close to barrier ribs  30 , as this makes it possible to use the wall charge on phosphor layers  31  to  33  near barrier ribs  30  to expand the magnitude of the discharge. This structure can also be applied to embodiments 18 to 24 below. 
     Embodiment 18 
     FIG. 30 is a view from above of the display electrodes according to embodiment 18. Embodiment 18 differs from embodiment 17 in that protrusions  222  and  232  are formed as rectangles. For the same reasons given in embodiment 17, the electrode width according to embodiment 18 is such that W 2 ≦W 1 . 
     In addition to substantially the same effects as in embodiment 17, embodiment 18 achieves the following. 
     FIG. 31 is a graph showing the relationship between the surface area of the display electrodes and brightness when W 1 =W 2  in the PDP according to embodiment 18 As shown in FIG. 31, at electrode widths of 40 μm and below, brightness levels fall as a result of the decrease in discharge current related to the reduced electrode surface area. Brightness levels also begin to fall at electrode widths of 70 μm and above as a result of the decrease in the cell aperture rate related to the enlarged electrode surface area. Thus, panel brightness is optimized at electrode widths of 40 μm to 70 μm with respect to embodiment 18. On the other hand, luminous efficiency, which is shown by the slope of the unevenly-broken straight line in FIG. 31, is optimized at narrower electrode widths. Thus, in the actual manufacture of the PDP, it is preferable for the electrode widths to be such that 40 μm≦W 1 ≦70 μm and 10 μm≦W 2 ≦40 μm. 
     In the given example cell pitch P is 1.08 mm, the barrier rib pitch is ⅓ of cell pitch P, electrode length L is 0.37 mm, and the total width (x direction) W f  of the inner protrusion parts is 220 μm. The present invention is, however, not limited to these measurements, and the same effects can be achieved, for example, when 0. 9 mm≦P≦1.4 mm, 0. 05 mm≦L&lt;0.4 mm, and 0.08 mm≦W f ≦0.4 mm. 
     Embodiment 19 
     FIGS. 32 a  and  32   b  show a view from above of the display electrodes according to embodiment 19 In FIG. 32 a , display electrodes  22  and  23  have trapezoid-shaped protrusion parts, and in FIG. 32 b , display electrodes  22  and  23  have triangular-shaped protrusion parts. In comparison to embodiment 17, the protrusion parts W 2  and W 3  decreases in width as the distance from main discharge gap G increases. 
     In addition to substantially the same effects as in embodiment 17, embodiment 19 achieves the following. 
     Specifically, because of being able to secure sufficient capacitance in the wide section W 2  of protrusion part  222  arid  232  when the PDP is driven, it is possible to achieve an excellent discharge magnitude by relying on the tendency of the discharge plasma to expand out along the discharge electrode (i.e. the display electrode in the given example) after the smooth generation of a discharge in the vicinity of main discharge gap G, even when the width W 3  is relatively narrow. The discharge plasma is drawn along the narrow section W 3  of the protrusion part to the vicinity of barrier ribs  30  which are coated with phosphors, thereby suppressing any reduction in the density of the plasma. As a result, it is possible to maintain the required capacitance below existing levels, and thus reduce the power consumption of the PDP. 
     FIG. 33 is a graph showing the relationship between the surface area of the display electrodes and brightness when W 1 =W 2  in the PDP according to embodiment 19. As shown in FIG. 33, at electrode widths of 50 μm and below, brightness levels fall as a result of the decrease in discharge current related to the reduced electrode surface area. Brightness levels also begin to fall at electrode widths of 120 μm and greater as a result of the decrease in the cell aperture rate related to the enlarged electrode surface area. Thus, panel brightness is optimized at electrode widths of 50 μm to 120 μm with respect to embodiment 19. On the other hand, luminous efficiency, which is shown by the slope of the unevenly-broken straight line in FIG. 33, is optimized at narrower electrode widths. Thus, it is preferable for the electrode widths to be such that 50 μm≦W 1 ≦120 μm and 10 μm≦W 2 ≦50 μm. Also, it is preferable for W 3  to be such that 10 μm≦W 3 ≦40 μm. 
     Embodiment 20 
     FIGS. 34 a  and  34   b  show a view from above of the display electrodes according to embodiment 20. As shown in FIGS. 34 a  and  34   b , display electrodes  22  and  23  include line parts  221  and  231  and band-shaped inner protrusion parts  222  and  232 , which extend in the y direction. Each display electrode  22  ( 23 ) in a cell has two inner protrusion parts  222  ( 232 ). In embodiment 20, the electrode widths are such that W 2 ≦W 1 , and the effects are substantially the same as in embodiment 17. 
     The example shown in FIG. 34 a  is characterized by the fact that a width W 3  of line part  221  ( 231 ) between the two inner protrusion parts  222  ( 232 ) has been widened. This has the effect of improving the contrast ratio, because the widened section W 3  of line part  221  ( 231 ) shelters the set-up illumination when the PDP is driven, while at the same time reducing the electrical resistance of line part  221  ( 231 ). 
     In the example shown in FIG. 34 b , display electrodes  22  and  23  include outer protrusion parts  223  and  233 . This structure allows the magnitude of the discharge to expand to the outside of line parts  221  and  231  when the PDP is driven. 
     FIG. 35 is a graph showing the relationship between the surface area of the display electrodes and brightness when W 1 =W 2  in the PDP according to embodiment 20. As shown in FIG. 35, at electrode widths of 40 μm and below, brightness levels fall as a result of the decrease in discharge current related to the reduced electrode surface area. Brightness levels also begin to fall at electrode widths of 70 μm and greater as a result of the decrease in the cell aperture rate related to the enlarged electrode surface area. Thus, panel brightness is optimized at electrode widths of 40 μm to 70 μm with respect to embodiment 20. On the other hand, luminous efficiency, which is shown by the slope of the unevenly-broken straight line in FIG. 35, is optimized at narrower electrode widths. Thus, it is preferable for the electrode widths to be such that 40 μm≦W 1 ≦70 μm and 10 μm≦W 2 ≦70 μm. 
     FIG. 36 is a graph showing the results of a test calculation of brightness distribution across cells according to embodiment 20. Brightness distribution, defined as the visible light emitting from the aperture of a cell, was calculated as follows Each electrode in a cell was divided into a number of parts, each part being assigned an integral brightness distribution value proportionate to its respective surface area The various distribution values were then summed, giving a brightness distribution with respect to each cell. 
     As shown in FIG. 36, it is the central part of a cell that has the highest brightness, since this is where the plasma is generated (i.e. the discharge initiating part of the cell close to main discharge gap G) and expands out toward the perimeter of the cell. Thus it is possible for the PDP having band-shaped inner protrusion parts  222  and  232  as per embodiment 20 to achieve excellent panel brightness and luminous efficiency as a result of the cell aperture being secured along the part of the cell in which the plasma is generated and expands. 
     Table 10 compares the panel brightness and luminous efficiencies of embodiments 17 and 20. 
     
       
         
           
               
               
               
               
               
               
             
               
                   
                 TABLE 10 
               
               
                   
                   
               
               
                   
                 W1 
                 W2 
                 W3 
                 brightness 
                 rel. luminous 
               
               
                   
                 [μm] 
                 [μm] 
                 [μm] 
                 B [cd/m 2 ] 
                 efficiency [η] 
               
               
                   
                   
               
             
            
               
                   
               
            
           
           
               
               
               
               
               
               
            
               
                 embodiment 17 
                 60 
                 40 
                 — 
                 450 
                 1.0 
               
               
                 embodiment 20 
                 60 
                 40 
                 120 
                 495 
                 1.1 
               
               
                   
               
            
           
         
       
     
     As shown in table 10, it is possible to realize a PDP having excellent brightness according to embodiment 20. This effect is gained as a result of the display electrode structure that combines inner protrusion parts  222 ,  232  and outer protrusion parts  223 ,  233 . 
     In the given example cell pitch P is 1.08 mm, the barrier rib pitch is ⅓ of cell pitch P, electrode length L is 0.37 mm, and the total width (x direction) W f  of the inner protrusion parts is 220 μm. The present invention is, however, not limited to these measurements, and the same effects can be achieved, for example, when 0.9 μmm≦P≦1.4 mm, 0.05 mm≦L&lt;0.4 mm, and 0.08 mm≦W f ≦0.4 mm. 
     Embodiment 21 
     FIGS. 37 a  and  37   b  show a view from above of the display electrodes according to embodiment 21. In comparison to embodiment 17, inner protrusion parts  222  and  232  are formed as in a pointed triangular shape (FIG. 37 a ) or in a rounded triangular shape (FIG. 37 b ). Further, the opposing tips of each of inner protrusion parts  222  and  232  are out of alignment, such that parts  222  and  232  in each cell are point symmetrical to each other with respect to the center of the cell. By arranging the tips of parts  222  and  232  so as to be out of alignment, it is possible to provide comparatively large display electrodes for a given cell size. Panel brightness can thus be improved because the distance traveled by the discharge plasma (i.e. discharge magnitude) is lengthened (i.e. enlarged), resulting in the excitation of a large area of the phosphor surface. 
     In addition to substantially the same effects as in embodiment 17, embodiment 21 achieves the following. 
     FIG. 38 is a graph showing the relationship between the surface area of the display electrodes and panel brightness when W 1 =W 2  in the PDP according to embodiment 21. As shown in FIG. 38, at electrode widths of 50 μm and below, brightness levels fall as a result of the decrease in discharge current related to the reduced electrode surface area. Brightness levels also begin to fall at electrode widths of 80 μm and greater as a result of the decrease in the cell aperture rate related to the enlarged electrode surface area. Thus, panel brightness is optimized at electrode widths of 50 μm to 80 μm with respect to embodiment 21. On the other hand, luminous efficiency, which is shown by the slope of the unevenly-broken straight line in FIG. 38, is optimized at narrower electrode widths. Thus, it is preferable for the electrode widths to be such that 50 μm≦W 1 80 μm and 10 μm ≦W 2 ≦50 μm. 
     Table 11 compares the panel brightness and luminous efficiencies of embodiments 17 and 21. 
     
       
         
           
               
               
               
               
               
             
               
                   
                 TABLE 11 
               
               
                   
                   
               
               
                   
                   
                   
                 brightness 
                 rel. luminous 
               
               
                   
                 W1 [μm] 
                 W2 [μm] 
                 B [cd/m 2 ] 
                 efficiency [η] 
               
               
                   
                   
               
             
            
               
                   
               
            
           
           
               
               
               
               
               
            
               
                 embodiment 17 
                 60 
                 40 
                 450 
                 1.0 
               
               
                 embodiment 21 
                 60 
                 40 
                 480 
                 1.1 
               
               
                   
               
            
           
         
       
     
     As shown in table 11, according to embodiment 21 it is possible to realize a PDP having excellent brightness and luminous efficiency in comparison to embodiment 17. 
     In the given example cell pitch P is 1.08 mm, the barrier rib pitch is ⅓ of cell pitch P, electrode length L is 0.37 mm, and the total width (x direction) W f  of the inner protrusion parts is 220 μm. The present invention is, however, not limited to these measurements, and the same effects can be achieved, for example, when 0.9 mm≦P≦1.4 mm, 0.05 mm≦L&lt;0.4 mm, and 0. 08 mm≦W f ≦0.4 mm. 
     Embodiment 22 
     FIGS. 39 a  and  39   b  show a view from above of the display electrodes according to embodiment 22. As shown in FIGS. 39 a  and  39   b , sustain electrode  23  includes line part  231  and protrusion parts  232   a  and  232   b , the parts  232   a  and  232   b  being provided above and below line part  231  in a diamond shape (FIG. 39 a ) or in an irregular hexagon shape (FIG. 39 b ). Scan electrode  22  includes line parts  22   a  and  22   b , which are arranged to face protrusion parts  232   a  and  232   b , respectively. 
     By configuring the electrodes according to embodiment 22, it thus becomes possible to achieve two main discharge gaps in each cell. Also, by establishing the width W 1  of line parts  22   a ,  22   b , and  231  to be narrower than the width W 2  of protrusion parts  232   a  and  232   b , it is possible to reduce the capacitance of line parts  22   a ,  22   b , and  231 . 
     In addition to substantially the same effects as in embodiment 17, embodiment 22 achieves the following. 
     Table 12 compares data relating to the display electrodes and panel brightness, etc, of embodiments 17 and 22. 
     
       
         
           
               
               
               
               
               
             
               
                   
                 TABLE 12 
               
               
                   
                   
               
               
                   
                   
                   
                 brightness 
                 rel. luminous 
               
               
                   
                 W1 [μm] 
                 W2 [μm] 
                 B [cd/m 2 ] 
                 efficiency [η] 
               
               
                   
                   
               
             
            
               
                   
               
            
           
           
               
               
               
               
               
            
               
                 embodiment 17 
                 60 
                 40 
                 450 
                 1.0 
               
               
                 embodiment 22 
                 60 
                 40 
                 500 
                 1.1 
               
               
                   
               
            
           
         
       
     
     As shown in table 11, according to embodiment 22 it is possible to realize a PDP having a higher brightness and luminous efficiency than embodiment 17. The sustain discharge is initiated in the region close to main discharge gap G when the PDP is driven, and as well known, it is this region that has the highest illumination brightness. Thus by providing two main discharge gaps G as per embodiment 22, it is possible to achieve excellent panel brightness. 
     Although in embodiment 22, the display electrodes are arranged such that sustain electrode  23  is sandwiched between line parts  22   a  and  22   b  of scan electrode  22 , it is possible to reverse this structure so that scan electrode  22  is sandwiched between line parts  22   a  and  22   b  of sustain electrode  23 . 
     Embodiment 23 
     FIGS. 40 a  and  40   b  show a view from above of the display electrodes according to embodiment 23. In comparison to embodiment 22, scan electrode  22  includes line parts  22   a  and  22   b , and sustain electrode  23  is sandwiched between parts  22   a  and  22   b . Scan electrode  22  also includes protrusion parts  222   a  and  222   b , which extend toward sustain electrode  23  from line parts  22   a  and  22   b , respectively. Protrusion parts  222   a  and  222   b  may be formed in a trapezoid shape (FIG. 40 a ) or in a triangular shape (FIG. 40 b ). By forming the display electrodes in this manner it is possible to secure two main discharge gaps G in each cell. 
     This structure of the display electrodes is employed for the following reasons. 
     Specifically, in recent years, the inventors involved in the design of the present invention have being using methods such as space-time analysis estimation to conduct detailed studies into the expansion process of plasma when a discharge is generated in a cell of an AC PDP. Experimentation has shown that, with respect to an electrode structure consisting of a pair of display electrodes  22  and  23  provided on the same surface of a plate, discharge plasma is generated at the anode-side display electrode facing main discharge gap G, and then the glow expands toward the cathode-side display electrode, until finally the discharge has spread throughout the entire cell. The experiments have also shown that an illumination spot is generated on the anode-side display electrode, and that this spot remains substantially unchanged for the duration of the discharge. 
     Embodiment 23 takes advantage of this characteristic of the discharge. Specifically, in a central part of the cell are provided two main discharge gaps G from which to initiate sustain discharges having excellent brightness. The discharges generated at the two gaps G then gradually expand along protrusion parts  222   a  and  222   b  until they reach line parts  22   a  and  22   b.    
     In addition to substantially the same effects as in embodiment 17, embodiment 23 achieves the following. 
     Table 13 compares the display capacity (i.e. panel brightness, luminous efficiency, etc) in the PDPs according to embodiments 17, 22, and 23. 
     
       
         
           
               
               
               
               
               
             
               
                   
                 TABLE 13 
               
               
                   
                   
               
               
                   
                   
                   
                 brightness 
                 rel. luminous 
               
               
                   
                 W1 [μm] 
                 W2 [μm] 
                 B [cd/m 2 ] 
                 efficiency [η] 
               
               
                   
                   
               
             
            
               
                   
               
            
           
           
               
               
               
               
               
            
               
                 embodiment 17 
                 60 
                 40 
                 450 
                 1.0 
               
               
                 embodiment 22 
                 60 
                 40 
                 500 
                 1.1 
               
               
                 embodiment 23 
                 60 
                 40 
                 540 
                 1.2 
               
               
                   
               
            
           
         
       
     
     As shown in table 13, embodiment 23 is able to achieve excellent panel brightness and luminous efficiency in comparison to embodiments 17 and 22. 
     As with embodiment 22, it is also possible to reverse the arrangement of scan electrode  22  and sustain electrode  23  while maintaining the same electrode structure. 
     Embodiment 24 
     FIGS. 41 a  and  41   b  show a view from above of the display electrodes according to embodiment 24. According to this embodiment, display electrode  22  ( 23 ) includes line part  221  ( 231 ) and either band-shaped protrusion parts  222  ( 232 ) as in or FIG. 41 a  or hook-shaped protrusion parts  222  ( 322 ) as in FIG. 41 b . Main discharge gap G is defined in FIG. 41 a  as the shortest distance between protrusion parts  222  and  232 , and in FIG. 41 b  as the shortest distance between protrusion part  222  ( 232 ) and the hooked end of protrusion part  232  ( 222 ). 
     In addition to substantially the same effects as in embodiment 17, embodiment 24 achieves the following. 
     Specifically, in the prior art, there have been cases in which luminous efficiency has been improved by enlarging main discharge gap G, although this generally requires a high discharge initiating voltage. To suppress this increase in discharge initiating voltage, it is possible to reduce either the pressure of the discharge gas in the cells or the density of Xe in the discharge gas. However, these measures adversely reduce the luminous efficiency by decreasing panel brightness. 
     In contrast, by securing a main discharge gap G over a large area (i.e. the facing edges of protrusion parts  222  and  232  in the y direction) as per the electrode structure according to embodiments 24a and 24b, it is possible to achieve excellent luminous efficiency, even though gap G may be comparatively narrow. 
     Table 14 compares the capacity of the PDPs according to embodiments 17 and 24a/b. 
     
       
         
           
               
               
               
               
               
               
             
               
                   
                 TABLE 14 
               
               
                   
                   
               
               
                   
                 W1 
                 W2 
                 W3 
                 brightness 
                 rel. luminous 
               
               
                   
                 [μm] 
                 [μm] 
                 [μm] 
                 B [cd/m 2 ] 
                 efficiency [η] 
               
               
                   
                   
               
             
            
               
                   
               
            
           
           
               
               
               
               
               
               
            
               
                 embodiment 17 
                 60 
                 40 
                 — 
                 450 
                 1.0 
               
               
                 embodiment 
                 60 
                 40 
                 80 
                 490 
                 1.2 
               
               
                 24a 
               
               
                 embodiment 
                 60 
                 40 
                 80 
                 500 
                 1.2 
               
               
                 24b 
               
               
                   
               
            
           
         
       
     
     As shown in table 14, embodiments 24a and 24b are able to achieve excellent panel brightness and luminous efficiency. This is a result of being able to secure sufficient capacitance in the elongated (in the y direction) protrusion parts  222  and  232 , thereby making it possible to achieve excellent discharge magnitude and luminous efficiency. 
     INDUSTRIAL APPLICABILITY 
     The present invention is applicable in televisions, particularly those capable of high definition image reproduction, an example of which is high-vision television.