1. Field of the Invention
The present invention relates a structure of and a method of driving an AC plasma display panel (hereinafter also referred to as xe2x80x9cAC-PDPxe2x80x9d) and a plasma display device.
2. Description of the Background Art
Various researches are made on plasma display panels (PDP) as thin-type television or display monitors. AC-PDPs having memory functions include a surface discharge AC-PDP. The structure of this AC-PDP is now described with reference to FIG. 25.
FIG. 25 is a perspective view extracting and showing part of the structure of an AC-PDP 101 according to first background art. For example, Japanese Patent Application Laid-Open No. 7-140922 (1995) or Japanese Patent Application Laid-Open No. 7-287548 (1995) discloses an AC-PDP having such a structure. As shown in FIG. 25, the AC-PDP 101 comprises a front glass substrate 102 serving as a display surface and a rear glass substrate 103 opposed to the front glass substrate 102 through discharge spaces 111. While the glass substrates 102 and 103 are so arranged that the top portions of barrier ribs 110 are in contact with a dielectric layer 106A described later, FIG. 25 illustrates the glass substrates 102 and 103 in a separated state for convenience of illustration. This also applies to FIGS. 28 and 29 described later.
On a surface of the front glass substrate 102 closer to the discharge spaces 111, n row electrodes 104 and n row electrodes 105 (both are transparent electrodes) paired with each other are extended/formed. When metal auxiliary electrodes (also referred to as xe2x80x9cbus electrodesxe2x80x9d) 104a and 105a having low impedance for supplying a current from a circuit part are provided on partial surfaces of the row electrodes 104 and 105 respectively as shown in FIG. 25, the respective ones are referred to as xe2x80x9crow electrodes 104xe2x80x9d and xe2x80x9crow electrodes 105xe2x80x9d inclusive of the metal auxiliary electrodes respectively. The dielectric layer 106 is formed to cover both row electrodes 104 and 105. A protective film 107 of a dielectric substance such as MgO (magnesium oxide) may be formed on the surface of the dielectric layer 106 by a method such as vapor deposition as shown in FIG. 25, and the dielectric layer 106 and the protective film 107 are also generically referred to as xe2x80x9cdielectric layer 106Axe2x80x9d in this case.
On the surface of the rear glass substrate 103 closer to the discharge spaces 111, on the other hand, m column electrodes 108 are extended/formed to (grade-separately) intersect with the row electrodes 104 and 105, and the barrier ribs 110 are extended/formed between the adjacent ones of the column electrodes 108 in parallel with the column electrodes 108. The barrier ribs 110 separate respective discharge cells from each other while supporting the AC-PDP 101 not to be crushed under the atmospheric pressure.
A phosphor layer 109R for emitting red (R) light, a phosphor layer 109G for emitting green (G) light and a phosphor layer 109B for emitting blue (B) light (these phosphor layers 109R, 109G and 109B are also referred to as xe2x80x9cphosphor layers 109xe2x80x9d) are arranged in U-shaped trenches defined by the aforementioned surface of the rear glass substrate 103 and opposite side wall surfaces of the adjacent barrier ribs 110 in prescribed order to cover the column electrodes 108 in the form of stripes. There is also an ACP-DP having such a structure that a dielectric layer is provided on the aforementioned surface of the rear glass substrate 103 to cover the column electrodes 108 so that the barrier ribs 110 and the phosphor layers 109 are arranged on this dielectric layer.
The front glass substrate 102 and the rear glass substrate 103 having the aforementioned structures are sealed to each other along peripheral edge portions (not shown in FIG. 25) so that spaces (the discharge spaces 111) between the glass substrates 102 and 103 are filled with discharge gas such as an Nexe2x80x94Xe gas mixture or an Hexe2x80x94Xe gas mixture under pressure below the atmospheric pressure. In the AC-PDP 101, the grade-separate intersection between each pair of row electrodes 104 and 105 and each column electrode 108 defines a discharge cell (also referred to as xe2x80x9cluminous cellxe2x80x9d or xe2x80x9cdisplay cellxe2x80x9d). In a full color display PDP such as the AC-PDP 101, three discharge cells for emitting red light, green light and blue light form a single pixel. In this case, FIG. 25 shows the structure of the AC-PDP 101 for the single pixel.
In the following description, a transverse line of a luminous color obtained by lighting luminous cells of all luminous colors or arrangement of pixels necessary for displaying the transverse line is referred to as xe2x80x9cdisplay linexe2x80x9d. The AC-PDP 101 can light or select (discharge cells belonging to) a single display line when applying a prescribed voltage to a pair of row electrodes 104 and 105. Such arrangement that three discharge cells forming a single pixel are transversely aligned with each other may also be referred to as xe2x80x9cstripe arrangementxe2x80x9d.
In the AC-PDP 101, the discharge spaces 111, divided by the barrier ribs 110, extending along the longitudinal direction of the column electrodes 108 can be separated into (i) xe2x80x9cluminous areaxe2x80x9d or xe2x80x9cdisplay areaxe2x80x9d forming discharge cells to which the pairs of electrodes 104 and 105 belong and (ii) xe2x80x9cnon-luminous areaxe2x80x9d or xe2x80x9cnon-display areaxe2x80x9d between an adjacent pair of electrodes 104 and 105 (or each adjacent area of a plurality of discharge cells arranged along the aforementioned longitudinal direction) irrelevant to display luminescence of the PDP. In the following description, the structure forming the non-luminous area in the discharge spaces 111, i.e., the structure between discharge cells adjacent along the longitudinal direction of the column electrodes 108 is referred to as xe2x80x9cnon-discharge cell (or non-luminous cell or non-display cell)xe2x80x9d with respect to the luminous area forming the discharge cell for convenience.
Among gaps between the adjacent row electrodes 104 and 105, (i) a gap between two row electrodes 104 and 105 forming discharge in the discharge cell in a paired manner is referred to as xe2x80x9cdischarge gap DGxe2x80x9d while (ii) a gap between two opposite row electrodes 104 and 105 belonging to adjacent discharge cells respectively is referred to as xe2x80x9cnon-discharge gap NGxe2x80x9d. While the non-discharge cell has the discharge space 111 (non-discharge area) defined by the intersection between two row electrodes 104 and 105 (belonging to adjacent discharge cells respectively) and the column electrode 108 similarly to the discharge cell, the distance between the non-discharge gaps NG is so widely set as not to cause discharge in the AC-PDP 101.
Black insulating materials may be arranged on the aforementioned non-discharge cells. In this case, the black insulating materials, arranged in the form of stripes to appear as black transverse lines on the display surface of the PDP, may also be referred to as xe2x80x9cblack stripesxe2x80x9d. Thus, it is possible to improve contrast having been problematic since the phosphor material itself is white in a non-luminous state by blackening non-luminous cells irrelevant to image display.
An AC-PDP 201 according to second background art is now described with reference to FIGS. 26 and 27. FIG. 26 is a plan view of the AC-PDP 201 according to the second background art, and FIG. 27 is a longitudinal sectional view taken along the line-Ixe2x80x94I in FIG. 26. For example, Japanese Patent Application Laid-Open No. 6-12026 (1994) discloses an AC-PDP having such a structure. As shown in FIGS. 26 and 27, the AC-PDP 201 comprises a front glass substrate 202 serving as a display surface and a rear glass substrate 203 opposed to the front glass substrate 202 through discharge spaces 211. Row electrodes 204 and 205 are alternately formed on the surface of the front glass substrate 202 closer to the discharge spaces 211 at regular intervals. The row electrodes 204 and 205 may be formed by combination of transparent electrodes and bus electrodes similarly to the aforementioned AC-PDP 101, and the electrodes consisting of transparent electrodes and bus electrodes are also referred to as xe2x80x9crow electrodes 204 and 205xe2x80x9d in this case. A dielectric layer 206 and a protective film 207 (also generically referred to as xe2x80x9cdielectric layer 206Axe2x80x9d) are successively formed on the row electrodes 204 and 205.
Column electrodes 208 are extended/formed on the rear glass substrate 203 to (grade-separately) intersect with the row electrodes 204 and 205, and a dielectric layer 212 is formed to cover the column electrodes 208. The glass substrates 202 and 203 are opposed to each other through barrier ribs 210. As shown in FIG. 26, the space between the glass substrates 202 and 203 is divided into a plurality of hexagonal discharge spaces 211 by the glass substrates 202 and 203 and the barrier ribs 210. The barrier ribs 210 are so arranged that the centers of the respective discharge spaces 211 substantially match with the intersections of the gaps between the adjacent row electrodes 204 and 205 and the column electrodes 208 in the plan view shown in FIG. 26. In the AC-PDP 201, the respective gaps between the adjacent row electrodes 204 and 205 define discharge gaps DG, with no presence of non-discharge gaps, i.e., non-discharge cells. Thus, each discharge cell defined by the intersection between each pair of row electrodes 204 and 205 and each column electrode 208 is enclosed with the barrier ribs 210 and separated from adjacent discharge cells in the AC-PDP 201. As shown in FIG. 26, each column electrode 208 consists of a part opposed to the discharge spaces 211 and a part opposed to the barrier ribs 210, and these parts are alternately repeated at a pitch half that of the discharge cells arranged along the longitudinal direction of the column electrodes 208.
Phosphor layers 209 of the same luminous color are applied onto the dielectric layer 212 and to (parts of) the side wall surfaces of the barrier ribs 210 in the plurality of discharge cells arranged along each column electrode 208. In other words, a plurality of discharge cells for a luminous color of red (R), green (G) or blue (B) are arranged along each column electrode 208. In other words, each column electrode 208 corresponds to a single luminous color (or display color). In the AC-PDP 210, therefore, three discharge cells (FIG. 26 shows exemplary arrangement by symbols R, G and B) for respective luminous colors arranged in the form of a delta form a pixel for white display, and such arrangement of the discharge cells may also be referred to as xe2x80x9cdelta arrangementxe2x80x9d. The remaining structure such as discharge gas is similar to that of the first background art.
The AC-PDP 101 (and AC-PDPs 301 and 401 described later) having the discharge cells of stripe arrangement and the AC-PDP 210 having the discharge cells of delta arrangement are compared with each other for describing the difference between the structures thereof.
The AC-PDP 101 can light the respective luminous cells of red, green and blue by controlling a voltage applied to the column electrodes 108 when applying a prescribed voltage to a pair of row electrodes 104 and 105. In other words, the pair of row electrodes 104 and 105 corresponds to a single display line.
In the AC-PDP 201, on the other hand, a single pixel is formed by discharge cells for respective luminous colors arranged in the form of a delta and the respective discharge cells are arranged with displacement by half the pitch of arrangement thereof. In order to light (luminous cells belonging to) a single display line, therefore, a voltage must be applied to three continuously arranged row electrodes, i.e., a pair of row electrodes 204 and 205 and still another row electrode 204 (or 205) adjacent thereto.
An AC-PDP 301 according to third background art is now described with reference to a perspective view of FIG. 28. For example, Japanese Patent Application Laid-Open No. 5-2993 (1993) discloses the structure of the AC-PDP 301. In the following description, elements of the AC-PDP 301 similar to those of the aforementioned AC-PDP 101 (see FIG. 25) are denoted by the same reference numerals. As shown in FIG. 28, the AC-PDP 301 has barrier ribs 110R arranged on the side of a rear glass substrate 103, barrier ribs 1101F1 arranged on the side of a front glass substrate 103 and stripe barrier ribs 1101F2 arranged perpendicularly thereto, in correspondence to the barrier ribs 110 of the AC-PDP 101 shown in FIG. 25. In this case, the barrier ribs 110F2 separate a plurality of discharge cells arranged along the barrier ribs 110F1 and 110R from each other.
In the AC-PDP 301, row electrodes 104 and 105S are formed immediately under the barrier ribs 110F2 at regular pitches as shapes extending over two discharge cells adjacent to each other through the barrier ribs 110F2. In other words, the row electrodes 104 and 105 of the AC-PDP 301 have such shapes that two row electrodes located at the center among two pairs of row electrodes (four in total) in the aforementioned AC-PDP 101 shown in FIG. 25 are integrated with each other. In the AC-PDP 301, the plurality of row electrodes 104 (or 105) are grouped into even and odd electrodes respectively and driven in units of the groups.
For example, Japanese Patent Application Laid-Open No. 9-160525 (1997) discloses an AC-PDP having a row electrode structure similar to that of the AC-PDP 301. Such an AC-PDP is now described with reference to a perspective view of FIG. 29 as an AC-PDP 401 according to fourth background art. In the AC-PDP 401, elements equivalent to those of the AC-PDP 101 are denoted by the same reference numerals. As shown in FIG. 29, the AC-PDP 401 has no barrier ribs 110F1 and 110F2 of the AC-PDP 301 shown in FIG. 28.
The AC-PDP 401 is driven by a driving circuit similar to that for the AC-PDP 301 as follows: A driving method of separating one frame period into an odd field and an even field and selecting a discharge cell, i.e., the so-called interlaced scanning is performed on the AC-PDP 401, thereby preventing interference on discharge between discharge cells adjacent to each other along column electrodes 108. Thus, no barrier ribs parallel to row electrodes 104 and 105 are necessary for separating the discharge cells adjacent to each other along the column electrodes 108. Therefore, the AC-PDP 401 having a structure substantially similar to that of the aforementioned AC-PDP 101 is higher in resolution than the AC-PDP 101.
When a single row electrode 104 or 105 extends over two discharge cells (or two display lines) adjacent to each other along the longitudinal direction of the column electrodes 108 as in the AC-PDP 301 shown in FIG. 28, barrier ribs must be basically arranged along the widths or the central axes of shorter sides of the row electrodes which are strip electrodes (in addition to barrier ribs parallel to the column electrodes) for separating the two adjacent cells from each other. When phosphor layers 109 are extended/formed in parallel with the column electrodes 108 (perpendicularly to the row electrodes 104 and 105) as in the AC-PDP 401 shown in FIG. 29, i.e., when discharge cells for respective luminous colors are in stripe arrangement, the barrier ribs 110F2 along the display lines can be eliminated by performing interlaced scanning as described above.
When the discharge cells for the respective luminous colors are in delta arrangement as in the AC-PDP 201 shown in FIGS. 26 and 27, on the other hand, the barrier ribs 210 cannot be eliminated since the phosphor layers 209 for the respective luminous colors are jumbled in the direction parallel to the column electrodes 208. In other words, the barrier ribs having the shapes enclosing the respective discharge cells are inevitably necessary.
Comparing the shapes of the barrier ribs in view of manufacturing processes for the PDPs, (a) the stripe barrier ribs of the AC-PDP 101 shown in FIG. 25 or the like are superior to (b) the barrier rib shapes of the AC-PDP 201 shown in FIGS. 26 and 27. This point is now described.
Comparing the PDPs in relation to formation of the phosphor layers, (a) phosphors for prescribed luminous colors may be applied along the aforementioned U-shaped trenches defined by the barrier ribs 110 and the like in units of the U-shaped trenches when the barrier ribs 110 are in the form of stripes as in the AC-PDP 101 shown in FIG. 25, and hence alignment with respect to the barrier ribs 110 in the phosphor application step is easy. On the other hand, (b) phosphors of the respective luminous colors must be applied with the pitch half that of arrangement of the discharge cells in the case of the shapes of the barrier ribs 210 shown in FIGS. 26 and 27, and hence higher alignment accuracy than that in the phosphor application step for the AC-PDP 101 or the like is required.
In an exhaust step for the space (discharge spaces) between the front and rear glass substrates bonded to each other and a discharge gas introduction step, (a) the stripe barrier ribs 110 provided in the AC-PDP 101 or the like are more preferable than (b) the barrier ribs 210 provided in the AC-PDP 201 for dividing the aforementioned space into completely enclosed discharge spaces, due to small conductance.
Also in view of discharge control in the PDP, the stripe barrier ribs 110 of the AC-PDP 101 or the like are more advantageous. In an AC-PDP having stripe barrier ribs, charged particles caused by discharge quickly spread along the longitudinal direction of the barrier ribs so that discharge controllability in address discharge, for example, can be improved by utilizing such charged particles.
In a display panel such as a PDP, resolution depends on the number of display cells formed in a prescribed display area. The resolution is increased as the number of display cells formed in a restricted display area is increased. In the case of the same resolution, the area of the display cells is preferably maximized for improving luminous efficiency of the display cells and the PDP. Therefore, it is preferable to maximize the area (display area) of a part related to image display and minimize the area (non-display area) of a part irrelevant to image display. In consideration of this point, it can be said that the structure of the AC-PDP 201 is desirable in view of luminous efficiency and resolution since (a) the AC-PDP 101 shown in FIG. 25 has non-discharge cells which are non-display areas while (b) the AC-PDP 201 shown in FIGS. 26 and 27 has no non-display areas.
When performing interlaced scanning and driving the AC-PDP 401 shown in FIG. 29, areas corresponding to the non-discharge cells of the AC-PDP 101 shown in FIG. 25 are utilized as discharge cells, more desirably in the point of resolution as compared with the AC-PDP 201. When performing interlaced scanning, upper and lower display lines adjacent to a certain display line are not lighted while the certain discharge cell is lighted, and hence the total area of light-controlled luminous cells is instantaneously equivalent to that of the AC-PDP 101. The time for lighting a single pixel by interlaced scanning is half that in the driving method not utilizing areas of non-discharge cells as discharge cells, and hence driving must be performed at a frequency twice that in such a driving method in order to attain desired luminance.
The display operation principle of the aforementioned AC-PDP 101 (or 201) is now described. First, a voltage pulse is applied across the pair of row electrodes 104 and 105 (or 204 and 205) for causing discharge. Ultraviolet rays resulting from this discharge excite the phosphor layers 109 (209) so that the discharge cells luminesce. Electrons and ions generated in the discharge spaces during this discharge move toward the row electrodes 104 and 105 (204 and 205) having opposite polarity thereto and are stored on the surface of the dielectric layer 106A (206A) located on the row electrodes 104 and 105 (204 and 205). Charges such as the electrons and ions thus stored on the surface of the dielectric layer 106A (206A) are referred to as xe2x80x9cwall chargesxe2x80x9d.
An electric field formed by the wall charges acts to weaken an electric field formed by the voltage applied across the row electrodes 104 and 105 (204 and 205), and hence the discharge rapidly disappears following formation of the wall charges. When applying a voltage pulse reversed in polarity across the row electrodes 104 and 105 (204 and 205) after the discharge disappears, discharge can be caused again since an electric field formed by superposition of the applied electric field and an electric field formed by wall charges is substantially applied to the discharge spaces. Thus, once discharge is caused, discharge can be caused again by applying a lower applied voltage (hereinafter also referred to as xe2x80x9csustain voltagexe2x80x9d) than the firing voltage, whereby discharge can be stationarily sustained by successively applying sustain voltages (hereinafter also referred to as xe2x80x9csustain pulsesxe2x80x9d) reversed in polarity across the row electrodes 104 and 105 (204 and 205). This discharge is hereinafter referred to as xe2x80x9csustain dischargexe2x80x9d.
This sustain discharge is maintained so far as the sustain pulses are applied until the wall charges disappear. An operation of making the wall charges disappear is referred to as xe2x80x9cerasingxe2x80x9d, while an operation of forming wall charges on the dielectric layer 106A (206A) in the initial stage of discharge is referred to as xe2x80x9cwritingxe2x80x9d. Therefore, characters, figures, images and the like can be displayed by first performing writing on arbitrary discharge cells on the screen of the AC-PDP and thereafter performing sustain discharge. Further, motion pictures can also be displayed by performing writing, sustain discharge and erasing at a high speed.
A more specific method of driving the conventional PDP is now described with reference to FIG. 30. For example, Japanese Patent Application Laid-Open No. 7-160218 (1995) (or Japanese Patent No. 2772753) discloses a method of driving the conventional AC-PDP 101 (see FIG. 25). FIG. 30 is a timing chart showing waveforms of driving voltages in a single subfield (SF) in the driving method. In the following description, each of n row electrodes 104 is referred to as xe2x80x9crow electrode Xixe2x80x9d (i=1 to n) and each of n row electrodes 105 is referred to as xe2x80x9crow electrode Yixe2x80x9d (i=1 to n), while n row electrodes Y1 to Yn are collectively referred to as xe2x80x9crow electrodes Yxe2x80x9d assuming that all row electrodes Y1 to Yn are driven with a single driving signal (voltage). Further, each of m column electrodes 108 is referred to as xe2x80x9ccolumn electrode Wjxe2x80x9d (=1 to m).
The subfield (SF) shown in FIG. 30 is one of a plurality of periods obtained by dividing a single frame (F) for image display. The subfield is further divided into three periods, i.e., xe2x80x9creset periodxe2x80x9d, xe2x80x9caddress periodxe2x80x9d and xe2x80x9csustain discharge period (also referred to as a sustain period or a display period)xe2x80x9d.
In the xe2x80x9creset periodxe2x80x9d, a display history at an end point of a preceding subfield is erased while priming particles for improving discharge probability in the subsequent address period are supplied. More specifically, a full writing pulse Vp having a voltage value capable of causing self-erase discharge on the trailing edge thereof is applied across all row electrodes X1 to Xn and row electrodes Y thereby erasing the display history. At this time, a voltage pulse Vp1 is applied to the column electrode Wj.
In the xe2x80x9caddress periodxe2x80x9d, only discharge cells to be displayed are selectively discharged by selecting a matrix for forming xe2x80x9caddress dischargexe2x80x9d on the discharge cells. More specifically, a scan pulse Vxg (voltage value Vxg ( less than 0)) is successively applied to the row electrodes Xi and a voltage pulse VwD (voltage value VwD ( greater than 0)) based on image data is applied to the column electrode(s) Wj in the discharge cell(s) to be lighted, thereby causing xe2x80x9cwriting dischargexe2x80x9d between the column electrode Wj and the row electrode Xi. During the address period, a subscan pulse Vysc (voltage value Vysc ( greater than 0)) is applied to the row electrodes Y. At this time, a potential difference (Vyscxe2x88x92Vxg) is applied across the row electrode Xi and the row electrode Yi. This potential difference (Vyscxe2x88x92Vxg), not starting discharge itself, can immediately cause (transfer) xe2x80x9cwriting sustain dischargexe2x80x9d between the row electrodes Xi and Yi with a trigger of the preceding writing discharge. Due to such address discharge, positive or negative wall charges are stored on the surface of the dielectric layer 106A (see FIG. 25) located on the discharge cell(s) in a quantity capable of causing sustain discharge only with later application of a sustain pulse Vs.
Thus, the xe2x80x9caddress dischargexe2x80x9d is formed by (i) xe2x80x9cwriting dischargexe2x80x9d selectively generated between the row electrode Xi and the column electrode Wj and (ii) xe2x80x9cwriting sustain dischargexe2x80x9d triggered by the xe2x80x9cwriting dischargexe2x80x9d and caused between the row electrode Xi and the row electrode Yi.
On the other hand, the discharge cell(s) turned out in image display (i.e., in the sustain discharge period) is not made to cause address discharge and hence no discharge is caused between the row electrodes Xi and Yi of the discharge cell(s) and no wall charges are stored as a matter of course.
The sustain discharge period follows the address period. In the sustain discharge period, the sustain pulse Vs is applied across the row electrodes Xi and Yi, thereby maintaining sustain discharge during this period in the discharge cell(s) subjected to the aforementioned writing. During the sustain discharge period, a voltage Vs2 set to substantially half the voltage value Vs of the sustain pulse Vs is applied to the column electrode Wj, so that sustain discharge can be stably started upon transition from the address period to the sustain period.
 less than Problem 1 greater than 
As described above, the stripe barrier ribs of the AC-PDP 101 or the like are advantageous to the barrier ribs, completely enclosing the discharge cells, of the AC-PDP 201 in view of formation of the phosphor layers, introduction of discharge gas and controllability of discharge. In the AC-PDP having stripe barrier ribs, however, false discharge may be readily induced between discharge cells arranged along the barrier ribs since charged particles resulting from discharge quickly spread along the longitudinal direction of the stripe barrier ribs.
In order to prevent such false discharge, the AC-PDP 101 is provided with the non-discharge areas or the non-discharge cells between the discharge cells arranged along the barrier ribs. When the non-discharge areas are thus provided, however, the utilization factor of the display area is disadvantageously reduced by the non-discharge areas.
When driving the PDP by interlaced scanning, as hereinabove described, it is possible to increase the display area utilization factor by utilizing the areas of the non-discharge cells in the AC-PDP 101 as discharge cells thereby increasing the resolution. However, only half the display area is instantaneously utilized in driving, and hence it is necessary to employ means of increasing the number of applied pulses per unit time, i.e., the driving frequency in order to attain luminance identically to the driving method performing no interlaced scanning. In this case, it is necessary to increase instantaneous suppliability of a power source and hence it may not be possible to attain improvement of the luminous efficiency as a result.
When utilizing the areas of the non-discharge cells in the AC-PDP 101 as discharge cells and performing driving with no interlaced scanning, it is difficult to drive two discharge cells arranged through a single row electrode to share this row electrode while preventing induction of false discharge therebetween without providing a barrier rib (see the barrier ribs 110F2 shown in FIG. 28) separating the two discharge cells from each other.
 less than Problem 2 greater than 
Induction of false discharge from a lighted discharge cell or a discharge cell to be lighted to a discharge cell adjacent thereto can be caused in any of the aforementioned AC-PDPs 101 to 401. Discharge cells arranged in parallel with display lines share pairs of row electrodes and hence discharge readily takes place beyond barrier ribs. When gaps are defined between top portions of barrier ribs and a glass substrate opposed to the barrier ribs, or when barrier ribs are cracked or broken to define gaps in a process of manufacturing a PDP, for example, charged particles in discharge diffuse through such gaps to readily cause false discharge beyond the barrier ribs. Therefore, the barrier ribs must have process accuracy in manufacturing and strength of their own.
Further, interference of electric fields across adjacent cells may cause false discharge beyond barrier ribs, for example. When column electrodes are displaced from prescribed positions, false discharge is readily caused. In the AC-PDP 101, a strong electric field is formed in a space where the row electrodes Xi and Yi and the column electrode Wj intersect with each other in the address period, for example, and hence such a strong electric field readily causes false discharge between adjacent discharge cells when the column electrodes Wj is displaced from a prescribed position.
 less than Problem 3 greater than 
It may be unpreferable to provide black stripes on the non-discharge areas of the AC-PDP 101 in view of visuality, since the boundaries between the luminous areas and the non-luminous areas are clearly recognizable as black transverse lines in this case.
(1) According to a first aspect of the present invention, an AC plasma display panel comprises a plurality of discharge cells having discharge gaps capable of forming desired discharge and arranged on a same plane and a plurality of non-discharge cells having non-discharge gaps harder to form discharge than the discharge gaps and arranged on the same plane, while the discharge gaps are arranged adjacently to each other through at least one non-discharge gap at least in a direction parallel to a display line.
According to the first aspect, the non-discharge gap is present between two discharge gaps in the direction parallel to the display line. As compared with the conventional AC plasma display panel having the discharge gaps adjacently arranged along the aforementioned direction, therefore, false discharge induced in another discharge cell due to discharge (and a voltage/electric field for controlling this discharge) in each discharge cell can be remarkably suppressed/prevented when driving the display line.
(2) According to a second aspect of the present invention, the AC plasma display panel further comprises a first substrate, a second substrate opposed to the first substrate at a prescribed distance, a plurality of barrier ribs dividing a space between the first substrate and the second substrate into a plurality of discharge spaces, a first electrode and a second electrode each including a strip first portion extending in parallel with the display line and a plurality of second portions connected to the first portion and extending toward the discharge cells, and arranged on the side of the first substrate, a dielectric substance covering at least one of the first and second electrodes, and a plurality of strip third electrodes each arranged on the side of the second substrate in a direction grade-separately intersecting with each first portion of the first and second electrodes for defining the discharge cells and the non discharge cells with the first and second electrodes, while the discharge gaps are formed by both edges of each second portion of the first and second electrodes opposed to each other in the discharge cells, and the non-discharge gaps are formed by both edges of a portion of each first portion of the first and second electrodes opposed through the non-discharge cells.
According to the second aspect, the aforementioned effect (1) can be attained in the so-called three-electrode surface discharge type AC plasma display panel.
(3) According to a third aspect of the present invention, second portions of the first and second electrodes is so arranged that the edges forming the discharge gaps are arranged to be along a longitudinal direction of the third electrodes.
According to the third aspect, (energy) loss of electrons in discharge can be remarkably reduced by lowering the height of discharge, whereby luminous efficiency can be improved.
(4) According to a fourth aspect of the present invention, the first and second electrodes include a plurality of first and second electrodes respectively, the plurality of first and second electrodes are alternately arranged, and the discharge gaps are arranged adjacently to each other through at least one of the non-discharge gaps in a direction perpendicular to the display line.
According to the fourth aspect, any of the aforementioned effects (1) to (3) can be attained on the overall surface of the AC plasma display panel.
(5) According to a fifth aspect of the present invention, two of the second portions present between two of the discharge gaps located on both sides of the first portion of the first or second electrode are connected to the first or second electrode held between the two of the discharge gaps.
According to the fifth aspect, an effect similar to the aforementioned effect (4) can be attained. Particularly when applying this connection mode to the AC plasma display panel according to the third aspect, reactive power can be remarkably suppressed.
(6) According to a sixth aspect of the present invention, the AC plasma display panel further comprises a first substrate, a second substrate opposed to the first substrate at a prescribed distance, a plurality of barrier ribs dividing a space between the first substrate and the second substrate into a plurality of discharge spaces, a first electrode and a second electrode each including a strip first portion extending in parallel with the display line and a strip second portion connected to the first portion and extending on both sides of the first portion with respect to a direction perpendicular to a longitudinal direction of the first portion to extend along the longitudinal direction of the first portion, and arranged on the side of the first substrate, a dielectric substance covering at least one of the first and second electrodes, a plurality of strip third electrodes each arranged on the side of the second substrate in a direction grade-separately intersecting with each first portion of the first and second electrodes for defining the discharge cells and the non-discharge cells with the first and second electrodes, and a discharge suppressor arranged at least on a grade-separate intersection of a gap between adjacent ones of second portions and the third electrodes for defining one of non-discharge cells, while the discharge gaps are formed by both edges of a portion of each second portion of the first and second electrodes opposed in the discharge cells, and the non-discharge gaps are formed by both edges of a portion of each second portion of the first and second electrodes opposed in the non-discharge cells.
According to the sixth aspect, the aforementioned effect (1) can be attained in the so-called three-electrode surface discharge type AC plasma display panel.
(7) According to a seventh aspect of the present invention, the discharge suppressor is arranged on the side of the second substrate.
According to the seventh aspect, the discharge cells and the non-discharge cells can be reliably formed even if misalignment takes place when bonding the first and second substrates to each other. As compared with the AC plasma display panel according to the second aspect, therefore, alignment accuracy in the aforementioned bonding step can be relaxed.
(8) According to an eighth aspect of the present invention, the discharge suppressor has a height equivalent to the barrier ribs.
According to the eighth aspect, the discharge suppressors and the barrier ribs can be collectively formed. Therefore, the discharge suppressors can be formed without increasing the number of manufacturing steps and complicating the manufacturing steps.
(9) According to a ninth aspect of the present invention, the discharge suppressor is arranged on the side of the first substrate, and the dielectric substance includes an electrode covering portion covering at least one of the first and second electrodes and a convex portion forming the discharge suppressor.
According to the ninth aspect, convex portions forming the discharge suppressors serve as guides for the plurality of discharge spaces divided by the barrier ribs in the step of bonding the first and second substrates to each other, whereby the first and second substrates are hardly misaligned with each other.
(10) According to a tenth aspect of the present invention, the discharge suppressor is not in contact with the barrier ribs.
According to the tenth aspect, the spaces are defined between the discharge suppressors and the barrier ribs, not to hinder execution of an exhaust step and a discharge gas introduction step for manufacturing the AC plasma display panel.
(11) According to an eleventh aspect of the present invention, the discharge suppressor is black at least on the side of the first substrate.
According to the eleventh aspect, high contrast and visuality can be attained.
(12) According to a twelfth aspect of the present invention, the first and second electrodes include a plurality of first and second electrodes respectively, the plurality of first and second electrodes are alternately arranged, and the discharge gaps are arranged adjacently to each other through at least one of the non-discharge gaps in a direction perpendicular to the display line.
According to the twelfth aspect, any of the aforementioned effects (6) to (11) can be attained on the overall surface of the AC plasma display panel.
(13) According to a thirteenth aspect of the present invention, at least one of the discharge cell is larger than at least one of the non-discharge cells when viewing the AC plasma display panel from the side of the first or second substrate.
According to the thirteenth aspect, the AC plasma display panel has a higher display area utilization factor than an AC plasma display panel (according to a sixteenth aspect) having discharge cells and non-discharge cells of the same size when having the same panel area and resolution, whereby luminous efficiency can be further improved. When rendering the panel area and the sizes of the discharge cells identical to those in the AC plasma display panel according to the sixteenth aspect, an AC plasma display panel having higher resolution can be implemented.
(14) According to a fourteenth aspect of the present invention, the plurality of barrier ribs include a plurality of strip barrier ribs arranged along a longitudinal direction of the third electrodes to separate adjacent ones of the third electrodes from each other, and at least one space between two adjacent ones of the strip barrier ribs is wider in a portion defining one of the discharge cells than in a portion defining one of the non-discharge cells.
According to the fourteenth aspect, when forming phosphor layers in U-shaped trenches defined by two adjacent barrier ribs and the second substrate, for example, portions of the phosphor layers in the non-discharge cells can be rendered thicker than portions in the discharge cells. Thus, in ultraviolet rays resulting from discharge caused in the discharge cells, those radiated toward the non-discharge cells can be converted to visible light in the phosphor layers in the aforementioned non-discharge cells. In other words, the utilization factor for the ultraviolet rays can be improved as compared with an AC plasma display panel having linearly arranged barrier ribs. In this case, portions of the discharge spaces forming the non-discharge cells are narrower than portions forming the discharge cells due to the difference of the thickness of the aforementioned phosphor layers, whereby discharge in the non-discharge cells can be more reliably prevented.
(15) According to a fifteenth aspect of the present invention, a space between both edges of the first portions of the first and second electrodes opposed through one of the discharge gaps is wider than a space between the both edges of first portions opposed through one of the non-discharge cells.
According to the fifteenth aspect, the discharge cells can be rendered larger than the non-discharge cells also when linearly forming the barrier ribs. Therefore, it is possible to sufficiently suppress cracking or breakage of the barrier ribs readily caused when meandering the barrier ribs.
(16) According to a sixteenth aspect of the present invention, the discharge cells are equal to the non-discharge cells in area when viewing the AC plasma display panel from the side of the first or second substrate.
According to the sixteenth aspect, the barrier ribs can be linearly formed, for example, whereby a conventional barrier rib forming step can be applied as such for forming barrier ribs capable of suppressing cracking or breakage.
(17) According to a seventeenth aspect of the present invention, the AC plasma display panel further comprises a first substrate, a second substrate opposed to the first substrate at a prescribed distance, a plurality of barrier ribs dividing a space between the first substrate and the second substrate into a plurality of discharge spaces, a first electrode and a second electrode each including a strip first portion extending in parallel with the display line and a plurality of second portions connected to the first portion and extending on both sides of the first portion with respect to a direction perpendicular to a longitudinal direction of the first portion, and arranged on the side of the first substrate, a dielectric substance covering at least one of the first and second electrodes, and a plurality of strip third electrodes each arranged on the side of the second substrate in a direction grade-separately intersecting with each first portion of the first and second electrodes for defining the discharge cells and the non-discharge cells with the first and second electrodes, while the discharge gaps are formed by both edges of each second portion of the first and second electrodes opposed to each other in the discharge cells, and the non-discharge gaps are formed by both edges of each second portion of the first and second electrodes opposed to each other through the non-discharge cells.
According to the seventeenth aspect, the aforementioned effect (1) can be attained in the so-called three-electrode surface discharge type plasma display panel.
(18) According to an eighteenth aspect of the present invention, the first and second electrodes include a plurality of first and second electrodes respectively, the plurality of first and second electrodes are alternately arranged, and the discharge gaps are arranged adjacently to each other through at least one of the non-discharge gaps in a direction perpendicular to the display line.
According to the eighteenth aspect, the aforementioned effect (17) can be attained on the overall surface of the AC plasma display panel.
(19) According to a nineteenth aspect of the present invention, two of the second portions present between two of the discharge gaps located on both sides of the first portion of the first or second electrode are connected to the first or second electrode held between the two of the discharge gaps.
According to the nineteenth aspect, an effect similar to the aforementioned effect (18) can be attained. In particular, reactive power can be remarkably suppressed.
(20) According to a twentieth aspect of the present invention, at least one of the discharge cells is larger than at least one of the non-discharge cells when viewing the AC plasma display panel from the side of the first or second substrate.
According to the twentieth aspect, an effect similar to the aforementioned effect (13) can be attained in the AC plasma display panel according to the-seventeenth aspect.
(21) According to a twenty-first aspect of the present invention, the first portion is linear, and a portion of second portions of the first and second electrodes on the side of the edges forming the discharge gaps with respect to the first portion is larger than a portion on the side of the edges forming the non-discharge gaps with respect to the first portion.
According to the twenty-first aspect, the first portion is linear and hence shape inconvenience of the first portion such as a pattern defect can be sufficiently suppressed as compared with the case of meandering the first portion.
(22) According to a twenty-second aspect of the present invention, the plurality of barrier ribs include a plurality of strip barrier ribs arranged along a longitudinal direction of the third electrodes to separate adjacent ones of the third electrodes from each other, and at least one space between two adjacent ones of the strip barrier ribs is wider in a portion defining one of the discharge cells than in a portion defining one of the non-discharge cells.
According to the twenty-second aspect, an effect similar to the aforementioned effect (14) can be attained in the AC plasma display panel according to the seventeenth aspect.
(23) According to a twenty-third aspect of the present invention, the first and second portions are made of an opaque conductive material, and the second portions have an opening.
According to the twenty-third aspect, the first and second portions can be collectively formed. Thus, the total number of steps for forming the first and second electrodes can be saved/simplified as compared with the case of employing transparent electrodes for the second portions. Consequently, the cost can be reduced.
(24) According to a twenty-fourth aspect of the present invention, the AC plasma display panel further comprises a black insulator arranged on a portion other than the discharge cells.
According to the twenty-fourth aspect, higher contrast and visuality can be attained as compared with a plasma display panel having the so-called black stripes.
(25) According to a twenty-fifth aspect of the present invention, the black insulator is arranged on a region corresponding to one of the non-discharge cells in a surface of the first substrate closer to the discharge spaces.
According to the thirty-fifth aspect, the discharge spaces in the non-discharge cells can be narrowed by the black insulators, whereby formation of discharge (false discharge) in the non-discharge cells can be more reliably prevented.
(26) According to a twenty-sixth aspect of the present invention, the black insulator is arranged on the second substrate.
According to the twenty-sixth aspect, an existing barrier rib forming step can be utilized as such by simply blackening a raw material for barrier ribs when forming the black insulators as parts or the whole of the barrier ribs, for example.
(27) According to a twenty-seventh aspect of the present invention, a width of the first portion is uniform along a longitudinal direction of the first portion.
According to the twenty-seventh aspect, the driving voltage margin can be enlarged while ensuring visuality for stably driving the AC plasma display panel by setting the width of the first portion to be smaller toward the center and larger toward each end. Further, the driving voltage margin can be further enlarged for more stably driving the AC plasma display panel as compared with the aforementioned case narrower at the center than each end by setting the width of the first portion to be larger toward the center and smaller toward each end.
(28) According to a twenty-eighth aspect of the present invention, the width of the first portion is smaller at the center and larger toward each end.
According to the twenty-eighth aspect, the resistance of the first portion can be lowered for reducing a voltage drop caused by the first portion as compared with the case of having a uniform width equivalent to the width of the center. Consequently, the driving voltage margin can be enlarged, for stably driving the AC plasma display panel. While luminance is reduced around the end portion as compared with the center, this does not lead to remarkable reduction of visuality.
(29) According to a twenty-ninth aspect of the present invention, the width of the first portion is larger at the center and smaller toward each end.
According to the twenty-ninth aspect, the aforementioned driving voltage margin can be more enlarged for further stably driving the AC plasma display panel as compared with the AC plasma display panel according to the twenty-eighth aspect.
(30) According to a thirtieth aspect of the present invention, a plasma display device comprises an AC plasma display panel including a plurality of discharge cells having discharge gaps capable of forming desired discharge and arranged on a same plane and a plurality of non-discharge cells having non-discharge gaps harder to form discharge than the discharge gaps and arranged on the same plane, while the discharge gaps are arranged adjacently to each other through at least one non-discharge gap at least in a direction parallel to a display line and a driving unit driving the plurality of discharge cells.
According to the thirtieth aspect of the present invention, it is possible to provide a plasma display device capable of exhibiting any of the aforementioned effects (1) to (9).
(31) According to a thirty-first aspect of the present invention, a driving method is for the AC plasma display panel according to the twenty-third aspect in which the first and second electrodes include a plurality of first and second electrodes respectively, and the plurality of first and second electrodes are alternately arranged and the discharge gaps are arranged adjacently to each other through at least one non-discharge gap in a direction perpendicular to the display line, and driving method does not simultaneously forms discharge in the discharge cells arranged on one side of the first portion and the discharge cells arranged on the other side.
According to the thirty-first aspect of the present invention, the instantaneous current flowing to the first and second electrodes can be reduced. Therefore, a voltage drop caused by the resistance of the first and second electrodes can be reduced for stably driving the AC plasma display panel.
A first object of the present invention is to provide a an AC plasma display panel capable of remarkably suppressing/removing false discharge.
A second object of the present invention is to provide an AC plasma display panel manufacturable with a process technique substantially identical to or easier than the method of manufacturing the AC-PDP 101 along with attainment of the aforementioned first object.
A third object of the present invention is to provide an AC plasma display panel more improved in visuality than a conventional AC-PDP along with attainment of the aforementioned first and second objects.
A fourth object of the present invention is to provide a stably drivable AC plasma display panel by increasing the driving voltage margin for the AC plasma display panel attaining the aforementioned first to third objects.
In addition, a fifth object of the present invention is to provide a plasma display device comprising the AC plasma display panel attaining the aforementioned first to fourth objects.
A sixth object of the present invention is to provide a driving method suitable for the AC plasma display panel attaining the aforementioned first to fourth objects.
USPTO Backgrounds
USPTO Backgrounds