JP2013152889A - Plasma display panel - Google Patents

Abstract

PROBLEM TO BE SOLVED: To suppress temperature gradient of an electrode terminal, by decreasing resistance being applied to sustain electrodes furthermore.SOLUTION: A plasma display panel includes a front substrate on which a plurality of scan electrodes and a plurality of sustain electrodes are formed, and a back substrate on which a plurality of data electrodes are formed, which are disposed to face each other. The plasma display panel is further provided with a first common electrode for short-circuiting the plurality of sustain electrodes electrically, a second common electrode connected electrically with the first common electrode and formed in parallel therewith, and a plurality of heat conduction parts connected electrically with the second common electrode. The heat conduction parts are formed in a solid state, and include hollow areas formed by hollowing out some of the heat conduction parts.

Description

  The present invention relates to a plasma display panel as a display device.

  Currently, a plasma display panel (hereinafter referred to as PDP) is mainly a surface discharge type having a three-electrode structure.

  In this surface discharge type PDP structure, a front plate and a rear plate, which are transparent at least on the front side, are arranged to face each other via a discharge space. A partition wall for partitioning the discharge space into a plurality of parts is disposed on the substrate, and an electrode group is disposed on the substrate so that discharge occurs in the discharge space partitioned by the partition wall.

  A plasma display device having such a PDP (hereinafter referred to as a PDP device) receives a sustain pulse from a scan electrode and a sustain electrode formed on a front plate via a flexible wiring board (hereinafter abbreviated as “FPC”). An image is displayed by applying the light alternately to generate discharge in the discharge cell to emit light.

  By the way, in recent years, electrical products with reduced power consumption have been desired for PDP devices. Also in the PDP, there is an expectation to reduce power consumption during driving. In particular, the power consumption of the developed PDP tends to increase due to the large screen and high definition of the PDP. For this reason, there is an increasing demand for technologies that realize power saving.

  By the way, with the increase in the screen size of the PDP, the current due to the sustain discharge increases, current concentration occurs near the electrode terminal on the sustain electrode side to which the FPC is connected, and the temperature rises locally at this portion. Therefore, in order to suppress the occurrence of a temperature gradient, a plurality of short-circuit wires that electrically short-circuit the sustain electrodes and a plurality of electrode terminals grouped into a plurality of electrode terminal groups that are electrically connected to the short-circuit wires are provided. There is a configuration of the PDP provided (for example, see Patent Document 1).

Japanese Unexamined Patent Publication No. 2011-100596

  In recent years, there has been a demand for a reduction in manufacturing cost while a large screen is required. Therefore, there is a need for a PDP that can suppress temperature rise even if the number of FPC connection locations is reduced. Therefore, an object of the present invention is to provide a PDP that exhibits a temperature suppressing effect that is higher than that of the conventional one even when the number of FPC connections is reduced.

  The present invention is a plasma display panel in which a front substrate on which a plurality of scan electrodes and a plurality of sustain electrodes are formed and a rear substrate on which a plurality of data electrodes are formed are arranged to face each other, and the plurality of sustain electrodes are electrically short-circuited. A first common electrode; a second common electrode electrically connected to the first common electrode and formed in parallel with the first common electrode; and a plurality of electrically connected to the second common electrode A heat conduction part, the heat conduction part is formed in a solid shape, and includes a cutout region in which a part of the heat conduction part is cut out.

  According to the present invention, the temperature gradient of the electrode terminal portion can be suppressed by further reducing the resistance applied to the sustain electrode.

1 is an exploded perspective view showing a PDP according to an embodiment of the present invention. Sectional drawing which shows the structure of the discharge cell part of PDP by embodiment of this invention The figure which shows the electrode arrangement | sequence structure of PDP by embodiment of this invention The block diagram which shows the whole structure of the PDP apparatus using PDP by embodiment of this invention The figure which shows the drive voltage waveform applied to each electrode of PDP by embodiment of this invention (A) Schematic diagram showing the display electrode pairs on the front panel of the PDP according to the embodiment of the present invention and the arrangement of the corresponding electrode terminals and the heat conduction part, (b) Display on the front panel of the PDP according to the embodiment of the present invention. Enlarged view of the schematic diagram showing the arrangement of the electrode pairs and the corresponding electrode terminals and heat conducting parts (A) The figure which shows arrangement | positioning of the flexible substrate connected to the electrode terminal formed in the front plate of PDP by embodiment of this invention, (b) It forms in the front plate of PDP by other embodiment of this invention Showing the arrangement of flexible substrates connected to the formed electrode terminals The figure which showed the temperature rise inhibitory effect about PDP by embodiment of this invention, and PDP by other embodiment of this invention

<Embodiment 1>
Hereinafter, the PDP according to the first embodiment of the present invention will be described with reference to the drawings. However, the embodiment of the present invention is not limited to the first embodiment.

  First, the overall configuration of the PDP according to Embodiment 1 of the present invention will be described with reference to the drawings.

1 and PDP Configuration FIG. 1 is an exploded perspective view showing a PDP according to Embodiment 1 of the present invention in a state where a front plate and a back plate are separated from each other, and FIG. It is sectional drawing which shows the discharge cell structure when it did. As shown in FIGS. 1 and 2, the PDP is configured by disposing a glass front plate 1 and a back plate 2 so as to form a discharge space 3 therebetween.

  The front plate 1 has a scanning electrode 5 as a conductive first electrode and a sustain electrode 6 as a second electrode arranged on a glass front substrate 4 in parallel with each other with a discharge gap MG. A plurality of display electrodes 7 are arranged in the row direction, and a dielectric layer 8 made of a glass material is formed so as to cover the scan electrodes 5 and the sustain electrodes 6. A protective film 9 made of MgO is formed on 8.

  Scan electrode 5 and sustain electrode 6 are each made of a conductive metal having a thickness of several μm made of Ag without using a transparent electrode such as ITO, and scan electrode 5 and sustain electrode 6 are shown in FIG. Thus, at least a two-layer structure (the illustrated one is two layers), and the lower layers 5a and 6a on the front substrate 4 side are made of a material containing a black metal oxide, and the upper layers 5b and 6b are lower layers 5a. The lower layer 5a, 6a of the front substrate 4 is configured to have a lower brightness than the upper layers 5b, 6b by configuring with a white material in which the Ag content is increased so that the specific resistance is smaller than 6a. Yes. That is, the display electrode 7 including the scan electrode 5 and the sustain electrode 6 is configured such that the brightness of the display electrode 7 including the scan electrode 5 and the sustain electrode 6 is low when viewed from the display surface on the front substrate 4 side. Thus, the light shielding member is not present between the display electrodes 7.

  The back plate 2 is provided with a plurality of data electrodes 12 made of Ag covered with an insulating layer 11 made of a glass material and arranged in a stripe shape in the column direction on a glass back substrate 10, and On the insulator layer 11, a grid-like partition wall 13 made of a glass material for partitioning the discharge space 3 between the front plate 1 and the back plate 2 for each discharge cell is provided. Further, red (R), green (G), and blue (B) phosphor layers 14R, 14G, and 14B are provided on the surface of the insulator layer 11 and the side surfaces of the partition walls 13. The front plate 1 and the back plate 2 are arranged to face each other so that the scan electrode 5 and the sustain electrode 6 intersect the data electrode 12, and the scan electrode 5, the sustain electrode 6 and the data electrode 12 intersect each other. As shown in FIG. 3, a discharge cell 15 is provided. The discharge space 3 is filled with, for example, a mixed gas of neon and xenon as a discharge gas. Note that the structure of the PDP is not limited to that described above, and for example, a structure having stripe-shaped partition walls may be used.

  Here, as shown in FIG. 2, the cross-shaped barrier ribs 13 forming the discharge cells 15 include a vertical barrier rib 13a formed in parallel to the data electrode 12, and a horizontal barrier rib formed so as to be orthogonal to the vertical barrier rib 13a. 13b. The phosphor layers 14R, 14G, and 14B formed by coating in the barrier ribs 13 are formed of stripes of blue phosphor layers 14B, red phosphor layers 14R, and green phosphor layers 14G along the vertical barrier ribs 13a. They are arranged in order.

  FIG. 3 is an electrode array diagram of the PDP shown in FIGS. N scanning electrodes Y1, Y2, Y3... Yn (5 in FIG. 1) and n sustaining electrodes X1, X2, X3... Xn (6 in FIG. 1) are arranged in a row. M data electrodes A1... Am (12 in FIG. 1) that are long in the direction are arranged. Discharge cells 15 are formed at portions where the pair of scan electrodes Y1 and sustain electrodes X1 and one data electrode A1 intersect, and m × n discharge cells 15 are formed in the discharge space. Further, as shown in FIG. 3, the scan electrode Y1 and the sustain electrode X1 are formed on the front plate 1 in a pattern that repeats in the arrangement of the scan electrode Y1, the sustain electrode X1, the sustain electrode X2, the scan electrode Y2,. Has been. Each of these electrodes is connected to a connection terminal provided at a peripheral end portion outside the image display area of the front plate 1 and the back plate 2.

2. Configuration of PDP Device Next, the overall configuration of the above-described plasma display device using the PDP (hereinafter referred to as a PDP device) will be described.

  FIG. 4 is a block diagram showing the overall configuration of the plasma display device. This PDP apparatus includes a PDP 21, an image signal processing circuit 22, a data electrode drive circuit 23, a scan electrode drive circuit 24, a sustain electrode drive circuit 25, a timing generation circuit 26, and a power supply circuit (not shown) configured as shown in FIGS. )). The data electrode drive circuit 23 includes a plurality of data drivers that are connected to one end of the data electrode 12 of the PDP 21 and are formed of semiconductor elements for supplying a voltage to the data electrode 12. The data electrode 12 is divided into a plurality of blocks as one block by several data electrodes 12, and a plurality of data drivers are connected to the electrode lead-out portion at the lower end of the PDP 21 in units of blocks.

  In FIG. 4, the image signal processing circuit 22 converts the image signal sig into image data for each subfield. The data electrode drive circuit 23 converts the image data for each subfield into signals corresponding to the data electrodes A1 to Am, and drives the data electrodes A1 to Am. The timing generation circuit 26 generates various timing signals based on the horizontal synchronization signal H and the vertical synchronization signal V, and supplies them to each drive circuit block. Scan electrode drive circuit 24 supplies drive voltage waveforms to scan electrodes Y1 to Yn based on timing signals, and sustain electrode drive circuit 25 supplies drive voltage waveforms to sustain electrodes X1 to Xn based on timing signals. Note that the sustain electrode side is commonly connected in the PDP 21 or outside the PDP 21, and then the common connection wiring is connected to the sustain electrode drive circuit 25.

3. Driving of PDP Next, a driving voltage waveform for driving the PDP 21 and its operation will be described with reference to FIG. FIG. 5 is a diagram showing drive voltage waveforms applied to the respective electrodes of the PDP 21.

  In PDP 21 according to the present embodiment, one field is divided into a plurality of subfields, and each subfield has an initialization period, an address period, and a sustain period.

3-1, Initialization Period In the initialization period of the first subfield, the data electrodes A1 to Am and the sustain electrodes X1 to Xn are held at 0 (V), and are equal to or lower than the discharge start voltage with respect to the scan electrodes Y1 to Yn. A ramp voltage that gradually rises from a voltage Vi1 (V) to a voltage Vi2 (V) that exceeds the discharge start voltage is applied. Then, the first weak initializing discharge is caused in all the discharge cells, negative wall voltages are accumulated on the scan electrodes Y1 to Yn, and positive walls on the sustain electrodes X1 to Xn and the data electrodes A1 to Am. The voltage is stored. Here, the wall voltage on the electrode refers to a voltage generated by wall charges accumulated on the dielectric layer or the phosphor layer covering the electrode.

  Thereafter, sustain electrodes X1 to Xn are maintained at positive voltage Vh (V), and a ramp voltage that gradually decreases from voltage Vi3 (V) to voltage Vi4 (V) is applied to scan electrodes Y1 to Yn. Then, the second weak initializing discharge is caused in all the discharge cells, the wall voltage between the scan electrodes Y1 to Yn and the sustain electrodes X1 to Xn is weakened, and the wall voltage on the data electrodes A1 to Am is reduced. Is also adjusted to a value suitable for the write operation.

3-2, Addressing Period In the subsequent addressing period, the scan electrodes Y1 to Yn are temporarily held at Vr (V). Next, the negative scan pulse voltage Va (V) is applied to the scan electrode Y1 in the first row, and the data electrode Ak (k = 1 to 1) of the discharge cell to be displayed in the first row among the data electrodes A1 to Am. A positive write pulse voltage Vd (V) is applied to m). At this time, the voltage at the intersection of the data electrode Ak and the scan electrode Y1 is obtained by adding the wall voltage on the data electrode Ak and the wall voltage on the scan electrode Y1 to the externally applied voltage (Vd−Va) (V). And the discharge start voltage is exceeded. An address discharge is generated between data electrode Ak and scan electrode Y1 and between sustain electrode X1 and scan electrode Y1, and a positive wall voltage is accumulated on scan electrode Y1 of the discharge cell. And a negative wall voltage is also accumulated on the data electrode Ak.

  In this manner, an address operation is performed in which address discharge is caused in the discharge cells to be displayed in the first row and wall voltage is accumulated on each electrode. On the other hand, since the voltage at the intersection of the data electrodes A1 to Am and the scan electrode Y1 to which the address pulse voltage Vd (V) is not applied does not exceed the discharge start voltage, the address discharge does not occur. The above address operation is sequentially performed until the discharge cell in the nth row, and the address period ends.

3-3, Sustain Period In the subsequent sustain period, the scan electrode Y1 to Yn has a positive sustain pulse voltage Vs (V) as the first voltage, and the sustain electrodes X1 to Xn have the ground voltage as the second voltage. 0 (V) is applied respectively. In the discharge cell in which the address discharge has occurred at this time, the voltage between the scan electrode Yi (i = 1 to n) and the sustain electrode Xi is equal to the sustain pulse voltage Vs (V) and the wall voltage on the scan electrode Yi. This is a sum of the wall voltage on the sustain electrode Xi and exceeds the discharge start voltage. Then, a sustain discharge occurs between the scan electrode Yi and the sustain electrode Xi, and the phosphor layer emits light by the ultraviolet rays generated at this time. A negative wall voltage is accumulated on scan electrode Yi, and a positive wall voltage is accumulated on sustain electrode Xi. At this time, a positive wall voltage is also accumulated on the data electrode Ak.

  In the discharge cells in which no address discharge has occurred in the address period, no sustain discharge occurs, and the wall voltage at the end of the initialization period is maintained. Subsequently, 0 (V) that is the second voltage is applied to scan electrodes Y1 to Yn, and sustain pulse voltage Vs (V) that is the first voltage is applied to sustain electrodes X1 to Xn. Then, in the discharge cell in which the sustain discharge has occurred, since the voltage between the sustain electrode Xi and the scan electrode Yi exceeds the discharge start voltage, the sustain discharge occurs again between the sustain electrode Xi and the scan electrode Yi, A negative wall voltage is accumulated on sustain electrode Xi, and a positive wall voltage is accumulated on scan electrode Yi.

3-4, the second and subsequent subfields Similarly, the address discharge is caused in the address period by alternately applying the number of sustain pulses corresponding to the luminance weight to the scan electrodes Y1 to Yn and the sustain electrodes X1 to Xn. The sustain discharge is continuously performed in the discharged cells. Thus, the maintenance operation in the maintenance period is completed. The operations in the initialization period, address period, and sustain period in the subsequent subfield are substantially the same as those in the first subfield, and thus description thereof is omitted.

4. About manufacturing method of PDP 4-1. Manufacturing method of front plate Scan electrode 5 and sustain electrode 6 are formed on front substrate 4 by photolithography. As a material for scan electrode 5 and sustain electrode 6, an electrode paste containing silver (Ag), a glass frit for binding silver, a photosensitive resin, a solvent, and the like is used. First, an electrode paste is applied on the front substrate 4 by a screen printing method or the like. Next, the solvent in the electrode paste is removed by a drying furnace. Next, the electrode paste is exposed through a photomask having a predetermined pattern.

  Next, the electrode paste is developed to form a display electrode pattern. Finally, the display electrode pattern is fired at a predetermined temperature in a firing furnace. That is, the photosensitive resin in the display electrode pattern is removed. Further, the glass frit in the electrode pattern is melted. Thereafter, the glass frit that has been melted is vitrified by cooling to room temperature. Through the above steps, scan electrode 5 and sustain electrode 6 are formed.

  Here, besides the method of screen printing the electrode paste, a sputtering method, a vapor deposition method, or the like can be used.

  Next, the dielectric layer 8 is formed. As a material for the dielectric layer 8, a dielectric paste containing a dielectric glass frit, a resin, a solvent, and the like is used. First, a dielectric paste is applied on the front substrate 4 by a die coating method or the like so as to cover the scan electrodes 5 and the sustain electrodes 6 with a predetermined thickness. Next, the solvent in the dielectric paste is removed by a drying furnace. Finally, the dielectric paste is fired at a predetermined temperature in a firing furnace. That is, the resin in the dielectric paste is removed. Further, the dielectric glass frit is melted. Thereafter, the cooled dielectric glass frit is vitrified by cooling to room temperature. Through the above steps, the dielectric layer 8 is formed. Here, besides the method of die coating the dielectric paste, a screen printing method, a spin coating method, or the like can be used. Alternatively, a film that becomes the dielectric layer 8 can be formed by a CVD (Chemical Vapor Deposition) method or the like without using the dielectric paste.

  Next, a protective film 9 is formed on the dielectric layer 8.

  Through the above steps, the front plate 1 having the scan electrode 5, the sustain electrode 6, the dielectric layer 8, and the protective film 9 on the front substrate 4 is completed.

4-2, Manufacturing Method of Back Plate 2 Data electrodes 12 are formed on the back substrate 10 by photolithography. As a material of the data electrode 12, a data electrode paste containing silver (Ag) for ensuring conductivity, a glass frit for binding silver, a photosensitive resin, a solvent, and the like is used. First, the data electrode paste is applied on the back substrate 10 with a predetermined thickness by screen printing or the like. Next, the solvent in the data electrode paste is removed by a drying furnace. Next, the data electrode paste is exposed through a photomask having a predetermined pattern. Next, the data electrode paste is developed to form a data electrode pattern. Finally, the data electrode pattern is fired at a predetermined temperature in a firing furnace. That is, the photosensitive resin in the data electrode pattern is removed. Further, the glass frit in the data electrode pattern is melted. Thereafter, the glass frit that has been melted is vitrified by cooling to room temperature. The data electrode 12 is formed by the above process. Here, besides the method of screen printing the data electrode paste, a sputtering method, a vapor deposition method, or the like can be used.

  Next, the insulator layer 11 is formed. As a material of the insulator layer 11, an insulator paste containing an insulator glass frit, a resin, a solvent, and the like is used. First, an insulating paste is applied by a screen printing method or the like so as to cover the data electrode 12 on the back substrate 10 on which the data electrode 12 is formed with a predetermined thickness. Next, the solvent in the insulator paste is removed by a drying furnace. Finally, the insulator paste is fired at a predetermined temperature in a firing furnace. That is, the resin in the insulator paste is removed. Moreover, the insulator glass frit is melted. Thereafter, by cooling to room temperature, the molten insulator glass frit is vitrified. The insulator layer 11 is formed by the above process. Here, in addition to the method of screen printing the insulator paste, a die coating method, a spin coating method, or the like can be used. In addition, a film to be the insulator layer 11 can be formed by CVD (Chemical Vapor Deposition) method or the like without using the insulator paste.

  Next, the partition wall 13 is formed by photolithography. As a material of the partition wall 13, a partition wall paste including a filler, a glass frit for binding the filler, a photosensitive resin, a solvent, and the like is used. First, the barrier rib paste is applied on the insulator layer 11 with a predetermined thickness by a die coating method or the like. Next, the solvent in the partition wall paste is removed by a drying furnace. Next, the barrier rib paste is exposed through a photomask having a predetermined pattern. Next, the barrier rib paste is developed to form a barrier rib pattern. Finally, the partition pattern is fired at a predetermined temperature in a firing furnace. That is, the photosensitive resin in the partition pattern is removed. Further, the glass frit in the partition wall pattern is melted. Thereafter, the glass frit that has been melted is vitrified by cooling to room temperature. The partition wall 13 is formed by the above process. Here, in addition to the photolithography method, a sandblast method or the like can be used.

  Next, the phosphor layer 14 is formed. As a material for the phosphor layer 14, a phosphor paste containing phosphor particles, a binder, a solvent, and the like is used. First, the phosphor paste is applied to the insulating layer 11 between the plurality of adjacent barrier ribs 13 and to the side surfaces of the barrier ribs 13 by a dispensing method or the like. Next, the solvent in the phosphor paste is removed by a drying furnace. Finally, the phosphor paste is fired at a predetermined temperature in a firing furnace. That is, the resin in the phosphor paste is removed. The phosphor layer 14 is formed by the above steps. Here, in addition to the dispensing method, a screen printing method or the like can be used.

  Through the above steps, the back plate 2 having the data electrode 12, the insulator layer 11, the partition wall 13, and the phosphor layer 14 on the back substrate 10 is completed.

4-3, Assembly Method of Front Plate 1 and Back Plate 2 First, a sealing paste is applied around the back plate 2 by a dispensing method or the like. The sealing paste may contain beads, a low-melting glass material, a binder, a solvent, and the like. The applied sealing paste forms a sealing paste layer (not shown). Next, the solvent in the sealing paste layer is removed by a drying furnace. Thereafter, the sealing paste layer is temporarily fired at a temperature of about 350 ° C. The resin component etc. in the sealing paste layer are removed by temporary baking. Next, the front plate 1 and the back plate 2 are arranged to face each other so that the display electrode 7 and the data electrode 12 are orthogonal to each other.

  Further, the peripheral portions of the front plate 1 and the back plate 2 are held in a state of being pressed by a clip or the like. In this state, the low melting point glass material is melted by firing at a predetermined temperature. Then, the low-melting-point glass material that has been melted is vitrified by cooling to room temperature. Thereby, the front plate 1 and the back plate 2 are hermetically sealed. Finally, a discharge gas containing Ne, Xe or the like is sealed in the discharge space, thereby completing the PDP 21.

5. About the region near the end on the sustain electrode side The structure around the electrode terminal on the sustain electrode side in the PDP of the present invention will be described with reference to FIGS. 6 (a) and 6 (b).

  In the vicinity of the electrode terminal on the sustain electrode side of the present invention, a first common electrode 28 that is electrically connected to a number of sustain electrodes 6 and is formed continuously in the short side direction of the PDP 21 is formed. As with the sustain electrode 6, an electrode paste containing silver (Ag), a glass frit for binding silver, a photosensitive resin, a solvent, and the like is used for the first common electrode 28.

  A second common electrode 29 is further formed outside the first common electrode 28. Similarly to the first common electrode 28, the second common electrode 29 is also formed continuously in the short side direction of the PDP 21. The second common electrode 29 is electrically connected to the first common electrode 28, but the first common electrode 28 and the second common electrode 29 are not continuously adjacent to each other. That is, as shown in FIGS. 6A and 6B, the first common electrode 28 and the second common electrode 29 are connected by a large number of sustain electrodes 6.

  The reason for adopting such a structure is to provide an adhesive region with the front substrate 4 whose adhesive strength with the sealing member 27 is stronger than that of the common electrode 28. When the adhesive strength between the sealing member 27 and the front plate 1 is weak, the discharge gas in the PDP 21 may leak and cannot be lit normally.

  Then, sustain electrode 6 applies the same drive voltage to each sustain electrode 6 from sustain electrode drive circuit 25 shown in FIG.

  Further, a plurality of electrode terminals 30 that are electrically connected to the second common electrode 29 and grouped into a plurality of terminal groups (hereinafter referred to as electrode terminal group 31) are formed. Each electrode terminal group 31 is connected to an FPC, and the FPC is connected to a sustain electrode drive circuit. Therefore, a voltage is applied to each sustain electrode 6 from the second common electrode through the first common electrode via the FPC from the sustain electrode driving circuit. Since each of sustain electrodes 6 is electrically short-circuited, the number of electrode terminals for sustain electrodes, the number of FPCs, and their attachment positions are arbitrary. That is, the number of electrode terminals 30, the number of FPCs, and the mounting position can be appropriately changed depending on the size of the PDP, the number of sustain electrodes, and the like.

  In FIG. 6A, 72 sustain electrodes and 24 electrode terminals 30 grouped in groups of 4 electrode terminals 31 in groups of 6 are electrically connected to the second common electrode. However, these are for making the drawing easy to see. In the present embodiment, for example, the electrode terminals 30 for sustain electrodes are grouped into four electrode terminal groups of 86 each.

  In addition, the second common electrode 29 is formed with a plurality of solid heat conduction portions 32 electrically connected to the second common electrode 29. The electrode terminal 30 is not formed in the region where the heat conducting portion 32 is formed. The heat conducting unit 32 is made of the same material as the sustain electrode 6, the first common electrode, and the second common electrode.

  As shown in FIG. 6 (b), among the plurality of heat conducting portions 32, the heat conducting portion 32 formed at the center in the short side direction of the PDP 21 is aligned when the front plate 1 and the back plate 2 are bonded together. For this purpose, a marker (hereinafter referred to as center marker 33) is formed. In the present embodiment, the heat conducting portion 32 on which the center marker is formed has a shape in which a rectangle having a width of 1.3 mm and a length of 23.8 mm is combined with a rectangle having a width of 2.7 mm and a length of 18.8 mm.

  The center marker 33 of the present invention has a part of the heat conduction portion 32 cut out. In the present embodiment, the size of the center marker 33 is hollowed out with a square of 0.38 mm on each side, vertically and horizontally, with an interval of 0.24 mm.

  In the present invention, since the heat conduction part 32 made of silver is formed to be balanced with the data electrode, the electrode area is larger, and four squares are hollowed out in the region of the heat conduction part 32. A center marker 33 is formed.

  Therefore, since the peripheral part of the center marker 33 is the heat conducting part 32, the electrode area is larger and the thermal conductivity is larger. As a result, the temperature rise near the center marker 33 can be further reduced.

  Next, the temperature distribution in the vicinity of the electrode terminal portion 30 on the sustain electrode 6 side in the present embodiment will be described.

  The present inventors measured the temperature distribution of the PDP 21 in the present embodiment in order to confirm the effect of the electrode area expansion in the vicinity of the electrode terminal portion on the sustain electrode side in the present embodiment.

  In the present embodiment, as shown in FIG. 7A, only one FPC is connected to the electrode terminal group 31, and the electrode adjacent to the heat conducting portion 32 formed at the center in the short side direction of the PDP 21. An FPC is connected to the terminal group 31. The reason for this is to minimize the current path and minimize the drop in supply voltage due to resistance. This is because the current density is the smallest when the current path to the sustain electrode 6 is taken into consideration.

  The temperature rise is measured with the PDP 21 standing vertically, and the measurement location is the first measurement location where the temperature is the highest in the outer peripheral region of the first common electrode 28. A point separated by 1 cm from the left and right in parallel with the long side direction of the PDP is defined as a second measurement point and a third measurement point, respectively. The temperature difference between adjacent temperature measurement points was calculated, and the larger temperature difference was taken as the measurement result. That is, if the temperature difference between the second measurement location and the first measurement location is greater than the temperature difference between the first measurement location and the third measurement location, the second measurement location And the temperature difference between the first measurement location and the first measurement location.

  In the first embodiment, as shown in FIG. 7A, there is one electrode terminal group 31 to which the FPC is connected, and the upper half of the PDP 21 is lit. That is, the upper 50% area of the PDP 21 was turned on as a display pattern. In this lighting pattern, the temperature immediately above the electrode terminal group 31 to which the FPC is connected is likely to rise. Therefore, the temperature at three measurement locations immediately above the electrode terminal group 31 to which the FPC is connected was measured to determine the temperature difference.

  On the other hand, as a comparison, in the PDP 21 in which the center marker 33 of the PDP 21 has four squares formed of the same silver as the electrode and the heat conducting portion 32 is not formed by being stretched, the temperatures at three locations were measured in the same manner. .

  As a result, the temperature difference of PDP21 measured as a comparative example was 14.5 ° C. On the other hand, in PDP21 in this Embodiment, it was 10.3 degreeC.

  That is, it has been found that by forming the heat conducting portion 32 around the center marker 33, the electrode area is ensured and the temperature rise near the FPC connection is suppressed.

<Embodiment 2>
Next, a second embodiment will be described. The description of the same contents as in the first embodiment is omitted.

  The PDP 21 described in Embodiment 2 has two FPCs connected to the electrode terminal group. As shown in FIG. 7B, the FPC is connected to a total of two electrode terminal groups, the first and fourth, in the short side direction of the PDP 21.

  In the second embodiment, as shown in FIG. 7B, there are two electrode terminal groups 31 to which the FPC 34 is connected, and the lower quarter of the PDP 21 is lit. That is, the lower 25% area of the PDP 21 was turned on as a display pattern. In this lighting pattern, the temperature immediately below the electrode terminal group 31 to which the FPC 34 is connected in the lighting area is likely to rise. Therefore, the temperature at three measurement locations immediately below the electrode terminal group 31 to which the FPC 34 is connected was measured to determine the temperature difference.

  As shown in FIG. 8, the temperature difference of the PDP 21 as a comparison was 6.5 ° C., whereas the temperature difference of the PDP 21 in the second embodiment was 6.3 ° C. Although the reduction effect of the temperature rise is small compared with Embodiment 1, it turns out that the temperature rise is suppressed by the area expansion in a heat conductive part.

  Note that the number of FPCs and the shape of the center marker shown in the first and second embodiments are merely examples, and it is preferable to set optimal conditions and shapes as appropriate according to the characteristics of the PDP and the process specifications.

  As for the size of the center marker to be cut out, the cutout area of the center marker can be 0.9 times the length of the lateral side of the heat conduction portion to be the maximum size of the square. In the case of the maximum size, one square is cut out. If the length is larger than 0.9 times the lateral length of the heat conducting portion, the electrode area is not sufficiently secured, and the effect of suppressing the temperature rise is reduced. On the other hand, the size of the center marker may be any size that can be recognized by the camera when the front plate and the back plate are bonded.

  Furthermore, the shape of the center marker may be a shape in which a circle or a triangle is cut out.

  Further, in FIG. 7 and the like, electrode terminal groups are formed in regions other than the electrode terminal group to which the FPC is connected. However, it is preferable that all electrode terminal groups to which the FPC is not connected are heat conducting portions. This is because the area of the electrode is further increased and concentration of current flowing from the sustain electrode driving circuit is suppressed.

  As described above, the present invention is useful for providing a plasma display panel with higher display quality.

DESCRIPTION OF SYMBOLS 1 Front plate 2 Back plate 3 Discharge space 4 Front substrate 5 Scan electrode 6 Sustain electrode 5a, 6a Lower layer 5b, 6b Upper layer 7 Display electrode 8 Dielectric layer 9 Protective film 10 Back substrate 11 Insulator layer 12 Data electrode 13 Partition 14R, 14G, 14B Phosphor layer 15 Discharge cell 21 Panel 22 Image signal processing circuit 23 Data electrode drive circuit 24 Scan electrode drive circuit 25 Sustain electrode drive circuit 26 Timing generation circuit 27 Sealing member 28 First common electrode 29 Second common Electrode 30 Electrode terminal 31 Electrode terminal group 32 Heat conduction part 33 Center marker 34 Flexible substrate

Claims (5)

A plasma display panel in which a front substrate on which a plurality of scan electrodes and a plurality of sustain electrodes are formed and a rear substrate on which a plurality of data electrodes are formed are arranged to face each other.
A first common electrode that electrically short-circuits the plurality of sustain electrodes; a second common electrode that is electrically connected to the first common electrode and formed in parallel with the first common electrode; A plurality of heat conducting portions electrically connected to the second common electrode,
The plasma display panel according to claim 1, wherein the heat conducting part is formed in a solid shape and includes a cutout region in which a part of the heat conducting part is cut out. The cutout region has four cutout regions, each cutout region is 0.38 mm in length and width, and an interval between adjacent cutout regions is 0.24 mm. Plasma display panel. The plasma display panel according to claim 1, wherein the heat conducting unit is made of a material similar to that of the sustain electrode. 2. The plasma according to claim 1, wherein a plurality of electrode terminals grouped into an electrode terminal group are formed on the front substrate between one heat conduction part and the other heat conduction part. Display panel. The plasma display panel according to claim 1, wherein a sealing frit is applied so as to cover a part of the first common electrode, and the front substrate and the rear substrate are sealed.