JP3578035B2 - Driving method of AC discharge type plasma display panel - Google Patents

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a method for driving an AC discharge type plasma display panel (AC-PDP (Plasma Display Panel)), and in particular, as a flat display which can be easily enlarged, a personal computer, a display output device of a workstation, and a wall-mounted television. The present invention relates to a method for driving an AC-PDP used for such purposes.
[0002]
[Prior art]
Depending on the structural classification, PDPs include a DC type in which the electrodes are exposed to the discharge gas, and an AC type in which the electrodes are covered with the dielectric and are not directly exposed to the discharge gas. Further, the AC type includes a memory operation type using a memory function based on the charge storage action of the dielectric and a refresh operation type not using the memory function.
[0003]
FIG. 6 is a sectional view showing an example of the configuration of a general AC-PDP. The PDP has the following structure in a space between a front substrate 10 made of glass and a rear substrate 11 made of glass. That is, a plurality of scanning electrodes 12 and a plurality of common electrodes 13 extending in a direction perpendicular to the paper surface are formed at predetermined intervals on the front substrate 10. The scanning electrode 12 and the common electrode 13 are covered with an insulating layer 15a, and a protective layer 16 made of MgO or the like for protecting the insulating layer 15a from discharge is formed on the insulating layer 15a.
[0004]
A plurality of data electrodes 19 are formed on the back substrate 11 so as to extend in the left-right direction of the drawing so as to be orthogonal to the scanning electrodes 12 and the common electrodes 13. The data electrode 19 is covered with an insulating layer 15b, and a phosphor 18 is applied on the insulating layer 15b to convert ultraviolet light generated by electric discharge into visible light. If the phosphor 18 is applied to each pixel in, for example, red, green and blue (RGB), which are three primary colors of light, a PDP for color display can be obtained.
[0005]
Between the insulating layer 15a on the front substrate 10 and the insulating layer 15b on the rear substrate 11, a partition wall (not shown) for securing the discharge space 20 and separating pixels is formed. In the discharge space 20, He, Ne, Ar, Kr, Xe, N₂, O₂Or CO₂Is mixed as a discharge gas. The substrate only needs to be transparent at least on the front substrate 10 on the display surface side.
[0006]
FIG. 7 is a plan view of an electrode structure in the color PDP shown in FIG. In FIG. 7, the electrode structure of the color PDP has m scanning electrodes 12S._i(I = 1, 2,..., M)} are formed in the row direction, and n data electrodes 19 # D_j(J = 1, 2,..., N)} are formed in the column direction, and one pixel is formed at the intersection. Common electrode 13 ° C_i(I = 1, 2,..., M)} is the scanning electrode 12 {S_iAre paired with｝, are formed in the row direction, and both are parallel to each other.
[0007]
Next, a driving method of the conventional PDP configured as described above will be described. FIG. 8 is a timing chart showing a drive voltage waveform applied to each electrode of the color PDP of FIG.
[0008]
First, the erasing pulse 21 is applied to all the scanning electrodes 12 to stop the discharge state of the pixels emitting light before the time shown in FIG. The discharge operation by this pulse is called sustain discharge erase. Here, the erasing means an operation of reducing or eliminating wall charges, which will be described later.
[0009]
Next, a first pre-discharge pulse 22 a of negative polarity is applied to the common electrode 13, a second pre-discharge pulse 22 b of positive polarity is applied to the scan electrode 12, and between the common electrode 13 and the scan electrode 12. A potential difference exceeding the discharge start voltage is applied, and all the pixels are forcibly discharged and emitted. After that, a preliminary discharge erasing pulse 23 is applied to the scanning electrode 12 to erase the preliminary discharge of all pixels. The discharge operation by the pre-discharge erase pulse 23 is called pre-discharge erase. The pre-discharge and pre-discharge erasure facilitate subsequent write discharge.
[0010]
After the preliminary discharge and the preliminary discharge erase, the scan electrode S₁~ S_m, A scan pulse 24 is applied at a shifted timing, and the data electrode 19 (D₁~ D_n), A data pulse 27 is applied according to the display data. The oblique line of the data pulse 27 indicates that the presence or absence of the data pulse 27 is determined according to the presence or absence of the display data. In the pixel to which the data pulse 27 is applied when the scan pulse 24 is applied, a writing discharge occurs in the discharge space 20 between the scan electrode 12 and the data electrode 19. If 27 is not applied, no write discharge occurs. Since display information is written into each pixel based on the presence or absence of this discharge, this is called a write discharge.
[0011]
In the pixel in which the write discharge has occurred, positive charges called wall charges are accumulated in the insulating layer 15 a on the scan electrode 12. At this time, negative wall charges are accumulated in the dielectric layer 15b on the data electrode 19. The first sustain discharge is caused by the superposition of the positive potential due to the positive wall charges formed on the insulator layer 15 a on the scan electrode 12 and the first sustain pulse 25 having a negative polarity and applied to the common electrode 13. Occurs. When the first sustain discharge occurs, positive wall charges are accumulated on the insulating layer 15 a on the common electrode 13, and negative wall charges are accumulated on the insulating layer 15 a on the scan electrode 12. The second sustain pulse 26 applied to the scan electrode 12 is superimposed on the potential difference due to the wall charges, and a second sustain discharge is generated. In this manner, the potential difference due to the wall charges formed by the nth sustain discharge and the (n + 1) th sustain pulse are superimposed, and the sustain discharge is continued. Brightness is controlled by the number of sustain discharges.
[0012]
If the voltages of the sustain pulse 25 and the sustain pulse 26 are adjusted in advance to such an extent that a discharge is not generated by the pulse voltage alone, the pixel in which the write discharge has not been generated is applied before the first sustain pulse 25 is applied. Since there is no potential due to wall charges, even if the first sustain pulse 25 is applied, the first sustain discharge does not occur, and therefore, no sustain discharge thereafter. Usually, the application frequency of the sustain pulse 25 and the sustain pulse 26 is about 100 kHz, respectively, and the pulse shape is a rectangular pulse.
[0013]
In the driving voltage waveform of FIG. 8 described above, the period in which the erase pulse 21, the preliminary discharge pulses 22a, 22b and the preliminary discharge erase pulse 23 are applied is the preliminary discharge period, and the period in which the scan pulse 24 and the data pulse 27 are applied is the scan. The period in which the sustain pulses 25 and 26 are applied is called a sustain period. The pre-discharge period, the scan period, and the sustain period are collectively called a subfield.
[0014]
Next, a gray scale display method in a conventional PDP will be described with reference to FIG. One field, which is a period for displaying one screen (for example, 1/60 second), is divided into a plurality of subfields (for example, four subfields). Each subfield has the configuration shown in FIG. 8, and furthermore, each subfield can control display ON / OFF independently of other subfields. In addition, the length of the sustain period, that is, the number of sustain pulses differs in each subfield, and accordingly, the luminance also differs. In the four sub-field division as shown in FIG. 9, if each sub-field is adjusted so that the luminance ratio when each sub-field emits light alone is 1: 2: 4: 8, By the combination of field display ON / OFF, 16 levels of brightness display from a brightness ratio of 0 when all the subfields are not selected to a brightness ratio of 15 when all the subfields are selected can be performed.
[0015]
In general, one field is divided into n subfields, and the ratio of the length of the sustain period, the ratio of the number of sustain pulses, or the ratio of the luminance for each subfield is 1 (= 2⁰): 2 (= 2¹): ...: 2^n-2: 2^n-1Set to 2ⁿThe gradation display is enabled.
[0016]
[Problems to be solved by the invention]
However, as described above, in order to reliably generate the write discharge, it is necessary to perform the preliminary discharge and the preliminary discharge erasure before the write discharge, and the preliminary discharge and the preliminary discharge erasure are generated without depending on the display information. Therefore, even when all the subfields are not selected, that is, even in the case of black display, light emission occurs due to the preliminary discharge and the preliminary discharge erasure. For this reason, the contrast of the image is reduced.
[0017]
On the other hand, a technique of so-called "thinning-out" in which a PDP driving method is improved and a preliminary discharge is generated only in a predetermined pixel in each subfield has been proposed in Japanese Patent Application Laid-Open No. 08-221036. According to this technique, the luminance of black display can be reduced by thinning out the preliminary discharge. However, in order to thin out the preliminary discharge, there is a problem that an extra circuit and signal processing for selecting a pixel to be subjected to the preliminary discharge are required as compared with the related art in which the preliminary discharge is uniformly performed on all pixels.
[0018]
Further, a technique has been proposed in which a preliminary discharge is performed at a position different from the sustain discharge and the position is shielded from light. For example, Japanese Patent Application Laid-Open No. 10-307560 discloses a technique in which a preliminary discharge is performed at a boundary between adjacent pixels in a non-display row. However, this complicates the drive waveform for the pre-discharge, and increases the drive circuit for the pre-discharge to be applied to the common electrode or the scan electrode to a plurality of types in order to generate a discharge in a non-display row instead of a display row. There is a problem that necessity arises.
[0019]
Japanese Patent Application Laid-Open No. Hei 10-247456 discloses a technique in which a special pixel and an electrode for performing a preliminary discharge exclusively outside the display area are provided, and the preliminary discharge in the pixel is used as a seed to induce a preliminary discharge in a pixel in the display area. It has been disclosed. However, such a technique requires a new drive circuit to drive the pixels and electrodes dedicated to the preliminary discharge provided outside the display area. Furthermore, it is necessary to apply a drive waveform that is related to the drive waveform of the pixel in the display area and is completely different from the drive waveform, and a signal processing circuit for that is required.
[0020]
The present invention has been made in view of such a problem, and an alternating-current plasma display panel in which a preliminary driving in a pixel in a display region is generated with a small and reliable light emission intensity by a simple driving circuit to improve image contrast. It is an object of the present invention to provide a driving method.
[0021]
[Means for Solving the Problems]
Driving of the AC discharge type plasma display panel according to the present invention is such that at least one of the two glass substrates is transparent, a plurality of row electrodes are formed on one of the glass substrates, and a plurality of row electrodes are formed on the other glass substrate. A column electrode is formed and arranged opposite to each other with a predetermined gap therebetween, a discharge gas is sealed in the gap, a preliminary discharge of all pixels is performed in a preliminary discharge period, and a scan period following the preliminary discharge period is performed. A scan pulse is applied to the row electrode in a time-division manner, a data pulse is selectively applied to a column electrode in synchronization with the scan pulse to select a display pixel, and only the display pixel is used in a sustain period following the scan period. In a method of driving an AC discharge type plasma display panel performing sustain discharge,
The rising of the leading edge of the preliminary discharge pulse applied to the row electrodes except for the specific row electrode during the preliminary discharge period,Slower than the rising edge of the leading edge of the preliminary discharge pulse applied to the specific row electrode, a strong first preliminary discharge is generated in the pixels belonging to the specific row electrode, and the row electrodes except the specific row electrode are applied to the row electrodes except the specific row electrode. A second preliminary discharge, which is weaker than the first preliminary discharge, is generated in a pixel belonging to the pixel.
The specific row electrode is a row electrode to which the time-divided scan pulse is applied first, and when the time-divided scan pulse is first applied, the data pulse is applied to all the column electrodes. A display pixel selection discharge is generated in all pixels belonging to a row electrode to which the scan pulse is applied first.
[0022]
In the present invention, the first preliminary discharge generated in some pixels is made stronger than the second preliminary discharge generated in other pixels, so that excited particles such as ions and electrons around some pixels are generated. To increase the density of existence. As a result, the probability of occurrence of discharge in other pixels can be increased, so that the second preliminary discharge is performed to such an extent that the discharge probability is reduced by the conventional driving method and the generation of the discharge itself becomes uncertain. It is possible to achieve a weak discharge by reducing the applied voltage up to this point. Since the second discharge is weaker than the first discharge, its light emission is reduced, and the contrast of the display screen is improved in a region where the second discharge occurs.
[0023]
In another method for driving an AC discharge type plasma display panel according to the present invention, at least one of the two glass substrates is transparent, and one of the glass substrates is provided with a plurality of row electrodes, and the other is a glass substrate. A plurality of column electrodes are arranged opposite to each other with a predetermined gap therebetween, a discharge gas is sealed in the gap, a preliminary discharge of all pixels is performed in a preliminary discharge period, and a scan subsequent to the preliminary discharge period is performed. A scan pulse is applied to the row electrodes in a time-division period, a data pulse is selectively applied to a column electrode in synchronization with the scan pulse to select a display pixel, and the display pixel is selected in a sustain period following the scan period. In a method for driving an AC discharge type plasma display panel that performs sustain discharge only in pixels,
Make a pair during the preliminary discharge periodA pre-discharge pulse exceeding a discharge starting voltage of one polarity is applied to all of one of the row electrodes, and a pre-discharge pulse of the other polarity is applied to a specific one of the other row electrodes of the paired row electrodes. Without applying a preliminary discharge pulse to the other row electrodes other than the specific row electrode, and reliably generating the first preliminary discharge to the pixels belonging to the specific row electrode. Generating a second preliminary discharge weaker than the first preliminary discharge in a pixel belonging to a row electrode except for the specific row electrode,
The specific row electrode is a row electrode to which the time-divided scan pulse is applied first, and when the time-divided scan pulse is first applied, the data pulse is applied to all the column electrodes. A display pixel selection discharge is generated in all pixels belonging to a row electrode to which the scan pulse is applied first.
[0024]
According to still another method of driving an AC discharge type plasma display panel according to the present invention, at least one of the two glass substrates is transparent, and a plurality of row electrodes are formed on one of the glass substrates, and the other glass is formed. A substrate having a plurality of column electrodes formed thereon is opposed to each other with a predetermined gap therebetween, a discharge gas is sealed in the gap, a preliminary discharge of all pixels is performed in a preliminary discharge period, and the pre-discharge period is continued. In a scanning period, a scanning pulse is applied to the row electrode in a time-division manner, a data pulse is selectively applied to a column electrode in synchronization with the scanning pulse to select a display pixel, and a display pixel is selected in a sustain period following the scanning period. In a method of driving an AC discharge type plasma display panel that performs sustain discharge only in display pixels,
The row electrodes forming a pair during the preliminary discharge periodApplying a pre-discharge pulse of one polarity to all of the row electrodes, applying a pre-discharge pulse of the other polarity to all of the other row electrodes of the pair of row electrodes, The rising edge of the leading edge of the pre-discharge pulse applied to the row electrode except for the row electrode is made slower than the rising edge of the leading edge of the pre-discharge pulse applied to the specific row electrode. A strong first preliminary discharge is generated, and a second preliminary discharge weaker than the first preliminary discharge is generated in a pixel belonging to a row electrode other than the specific row electrode,
The specific row electrode is a row electrode to which the time-division scan pulse is applied first, and when the time-division scan pulse is first applied, the data pulse is applied to all the column electrodes. The display pixel selection discharge is generated in all pixels belonging to a row electrode to which the scan pulse is applied first.
[0030]
Also, the specific lineThe electrodes areTop rowRow electrodeOr the bottom lineRow electrodeOne ofat leastIt is preferred to include.
[0031]
Further, the specific lineelectrodeIs the row power to which the time-divided scanning pulse is applied first.Polescan do.
[0032]
Furthermore,In the scanning period,Time-division scanning pulseWhen first applyingAll ofSaidApply the data pulse to the column electrodeThen, a display pixel selection discharge is generated in all pixels belonging to a row electrode to which the scan pulse is first applied.You may. As a result, in the row of pixels to which the scan pulse is applied first, a write discharge occurs in all the pixels. Therefore, when a write discharge is performed by applying a data pulse, the discharge of these pixels is similar to the preliminary discharge. It is possible to improve the probability of discharge of adjacent pixels, thereby improving the probability of writing discharge of all pixels.
[0033]
Also,In the scanning period, when applying the time-division scanning pulse, if a data pulse is applied to the column electrode, a display pixel selection discharge that shifts to a subsequent sustain discharge is generated, and the data is applied to the column electrode. When a pulse is not applied, it does not shift to the subsequent sustain discharge.Discharge may be generated. thisToSince a discharge is generated when a scan pulse is applied to all pixels, the probability of occurrence of a write discharge due to the application of a data pulse is improved in all pixels due to discharge of the nearest pixel to which the scan pulse was applied immediately before. As a result, an image with high contrast can be reliably displayed with a short scanning pulse.
[0034]
Furthermore,The specific row electrode and a row electrode paired therewithAgainst the sustain dischargeOccursLetforPart or all of the sustain pulse, the scan pulse,Eliminate the sustain dischargeforSustain erase pulseAt least one ofIt is not necessary to apply. This allowsThe specific row electrode and a row electrode paired with the specific row electrode belong to the row electrode.Some pixels have only a function as a base point for inducing preliminary discharge of other pixels, and power consumption can be reduced by eliminating the application of other driving pulses.
[0035]
Furthermore, the phosphor may not be applied to some of the pixels.
[0036]
Further, some of the pixels may have a light shielding layer on the display surface side.
[0037]
BEST MODE FOR CARRYING OUT THE INVENTION
Hereinafter, a method of driving an AC-PDP according to an embodiment of the present invention will be described. The embodiment of the present invention will be described in the case where the present invention is applied to the above-described general three-electrode type AC-PDP shown in FIGS. FIG. 1 is a timing chart showing driving waveforms related to pre-discharge and pre-discharge erasure of the present embodiment.
[0038]
As shown in FIG. 1, a first preliminary discharge pulse 22a is applied to the common electrode 13 of all pixels for the AC-PDP shown in FIG.₁~ S_m｝, The first scan electrode S₁Only the second pre-discharge pulse 22b is applied to only the other scan electrodes S₂Or S_mDoes not apply the second preliminary discharge pulse 22b. Thereby, the first scan electrode S₁And the first common electrode C₁In the first pixel row that includes the following, the first preliminary discharge pulse 22a and the second preliminary discharge pulse 22b are superimposed to generate a preliminary discharge (hereinafter, referred to as a first preliminary discharge), and the second to m-th discharges occur. Scan electrode S₂Or S_mAnd the second to m-th common electrodes C₂Or C_mIn the second to m-th pixel rows including the above, a preliminary discharge (hereinafter, referred to as a second preliminary discharge) is generated only by the first preliminary discharge pulse 22a. After that, a preliminary discharge erasing pulse 23 is applied to the scanning electrode 12 to erase the preliminary discharge of all pixels.
[0039]
In the first predischarge, a strong predischarge occurs due to a large potential difference caused by the superposition of the first predischarge pulse 22a and the second predischarge pulse 22b, and the light emission amount of the predischarge is large. However, the second and subsequent pixel rows, that is, the common electrode 13 and the scan electrode S common to all pixels₂~ S_mSince the second pre-discharge generated at the intersection with the first pre-discharge is generated only by the potential difference due to the first pre-discharge pulse 22a, the generated pre-discharge is weak, and thus the light emission amount is small.
[0040]
This will be described in comparison with the driving waveforms related to the conventional predischarge and predischarge erasure. FIG. 2 is a timing chart showing a driving waveform of the AC-PDP shown in FIG. 8 in a conventional preliminary discharge period. As shown in FIG. 2, conventionally, a first preliminary discharge pulse 22a is applied to a common electrode 13 of all pixels, and a scan electrode 12 (S₁~ S_m2), the second pre-discharge pulse 22b is applied, and a strong pre-discharge is generated in all the pixels due to the potential difference between the two.
[0041]
On the other hand, in the present embodiment, as described above, the display contrast of the second and subsequent pixel rows can be improved by reducing the light emission amount due to the preliminary discharge in the second and subsequent pixel rows.
[0042]
Next, the reason why a weak preliminary discharge can be generated in the second and subsequent pixel rows by generating a strong preliminary discharge in the first pixel row will be described. Generally, when a potential difference (discharge start voltage) larger than a predetermined threshold value is applied between the electrodes, discharge occurs. However, when the discharge is generated by the pulse voltage, when the duration of the voltage, that is, the pulse width is short, the discharge may not be generated even if a voltage exceeding the discharge start voltage is applied. This is because the occurrence of discharge is a stochastic phenomenon. The probability of occurrence of discharge increases as the applied voltage increases. That is, in the case where the discharge is controlled by a pulse like a PDP, unless a pulse voltage higher than the discharge starting voltage is applied in accordance with the pulse width, the occurrence of the discharge becomes uncertain and adversely affects the image display. In response to such a phenomenon of occurrence of discharge, the present inventors have found that the probability of occurrence of discharge largely depends on the atmospheric state at the time of occurrence of discharge. That is, the inventors of the present application have found that the probability of occurrence of discharge can be increased by setting an atmosphere state in which the density of excited particles such as ions and electrons is high.
[0043]
In PDPs, the easiest way to increase the density of excited particles such as ions and electrons is to generate a discharge. That is, when a discharge is continuously generated at the same position, or in the vicinity of the position where the discharge is generated, the density of the excited particles such as ions and electrons is high, so that the probability of generation of the discharge increases. The present invention utilizes such a phenomenon. That is, in the first pixel row, a discharge is reliably generated by increasing the applied voltage to increase the probability of discharge generation. However, in the second pixel row adjacent to the first pixel row, the first pixel row has the first voltage. Since the density of the excited particles such as ions and electrons is increased by the discharge of the pixel row, the probability of occurrence of the discharge increases, and even if a voltage lower than that of the first pixel row is applied to the second pixel row, 1 Is the same as the pixel rowrateCan generate a discharge. Further, also in the third pixel row adjacent to the second pixel row, the density of the excited particles such as ions and electrons in the third pixel row increases due to the discharge in the second pixel row, and the probability of the discharge occurrence The discharge can be generated even if a voltage lower than that of the first pixel row is applied by utilizing the fact that the voltage becomes higher. As described above, the discharge of all pixels (preliminary discharge in the case of the present embodiment) can be reliably generated by utilizing the increase in the probability of the occurrence of discharge due to the influence of the discharge in the sequentially adjacent rows.
[0044]
Although the peak value of the first pre-discharge pulse 22a shown in FIG. 1 needs to exceed the discharge starting voltage, the discharge probability is improved by the effect of the discharge of the adjacent rows sequentially transmitted from the first pixel row. Therefore, the potential difference applied to the second and subsequent pixel rows does not need to be large enough to ensure the occurrence of discharge only by the potential difference. As described above, by increasing the discharge probability by the discharge of the adjacent pixels, the required potential difference can be reduced as compared with the conventional pre-discharge in which the discharge is ensured only by the voltage. Can be weaker than the preliminary discharge. Accordingly, the amount of light emitted by the second preliminary discharge is reduced, so that the contrast in the second and subsequent pixel rows is improved. Further, since a small potential difference is required, power consumption of the driver circuit can be reduced.
[0045]
In addition, the driving circuit for applying the driving waveform shown in FIG.₁~ S_m), The second pre-discharge pulse 22b was output, but in this embodiment, the S₁Since only a circuit for outputting the second preliminary discharge pulse 22b can be provided, the S₂~ S_mThe circuit that has output the second pre-discharge pulse 22b can be eliminated. Therefore, the drive circuit of the present embodiment can be simplified more than the drive circuit for applying the conventional drive waveform, and the manufacturing cost can be reduced.
[0046]
Next, a second embodiment of the present invention will be described. FIG. 3 is a timing chart showing the driving waveforms of the pre-discharge pulse and the pre-discharge erase pulse of the present embodiment. As shown in FIG. 3, in the present embodiment, a first preliminary discharge pulse 22a is applied to the common electrode 13 of all pixels, and a second preliminary discharge pulse 22b is applied to the first scan electrode S.₁To the other scanning electrodes S₂~ S_mIs applied with a third preliminary discharge pulse 22c having a smaller peak value than the second preliminary discharge pulse 22b. First scan electrode S₁And the first common electrode C₁In the first pixel row that includes the first and second pre-discharge pulses 22a and 22b, a strong pre-discharge occurs due to a large potential difference created by superposition of the first and second pre-discharge pulses 22b, and the amount of light emitted by the pre-discharge is large. . However, in the second and subsequent pixel rows, a weak pre-discharge occurs due to a small potential difference generated by the superposition of the first pre-discharge pulse 22a and the third pre-discharge pulse 22c, so that the light emission amount is small. By reducing the amount of light emitted by the preliminary discharge, the display contrast of the second and subsequent pixel rows is improved.
[0047]
Also in this embodiment, the same action as in the first embodiment is obtained, and the density of the excited particles in the second pixel row adjacent to the first pixel row increases due to the discharge generated in the first pixel row. Since the probability of discharge increases, it is possible to reliably discharge even if the potential difference of the preliminary discharge pulse applied to the second pixel row is smaller than the potential difference of the preliminary discharge pulse applied to the first pixel row. As described above, the discharge can be easily caused by the influence of the discharge in the adjacent pixel row.
[0048]
Further, in the present embodiment, when the peak value of the first preliminary discharge pulse 22a alone cannot be set to a value exceeding the discharge starting voltage due to the limitation of the driving circuit, the shortage is used as the third preliminary discharge pulse 22c. Can be applied. Thus, in the first pixel row, the preliminary discharge is reliably generated by the large potential difference, and in the second and subsequent pixel rows, the discharge in the adjacent row is effectively used, and the weak preliminary discharge is reliably generated.
[0049]
In the first and second embodiments of the present invention, the first pre-discharge pulse 22a and the second pre-discharge pulse 22b are shown as rectangular waves, but these have a slow rise time and / or fall time. A similar effect can be obtained with a blunt waveform or a sawtooth waveform.
[0050]
Next, a third embodiment of the present invention will be described. FIG. 4 is a timing chart showing driving waveforms related to pre-discharge and pre-discharge erasure of the present embodiment. As shown in FIG. 4, in this embodiment, a first preliminary discharge pulse 22a is applied to the common electrode 13 of all pixels, and a second preliminary discharge pulse 22b is applied to the first scan electrode S.₁To the other scanning electrodes S₂~ S_m, A fourth preliminary discharge pulse 22d whose pulse rises later than the second preliminary discharge pulse 22b is applied. In the case where the discharge is generated by a slow rising blunt pulse, the generation of the discharge becomes more unstable than in the case where the discharge is generated by a fast rising rectangular pulse, but the emission luminance can be reduced. In this embodiment, the first scan electrode S₁And the first common electrode C₁In the first pixel row including the first and second pre-discharge pulses 22a and 22b, a discharge is reliably generated by superposition of the first and second pre-discharge pulses 22b. Therefore, as in the first and second embodiments, , The discharge probability of the adjacent second pixel row can be increased. As described above, even when the first preliminary discharge pulse 22a and the fourth preliminary discharge pulse 22d are superimposed on the second and subsequent pixel rows, the probability of occurrence of discharge can be increased, so that discharge can be reliably performed. Then, since the rising of the preliminary discharge pulse 22d is slow, a low-luminance discharge is generated. This improves the display contrast of the second and subsequent pixel rows.
[0051]
In the first to third embodiments, the second preliminary discharge pulse 22b applied to the scan electrode 12 is deleted in the second and subsequent pixel rows other than the first pixel row in the first embodiment, In the third embodiment, the first preliminary discharge pulse 22a applied to the common electrode 13 is deleted, reduced, or blunted except for the first pixel row. Has the same effect.
[0052]
Further, in all of the second and subsequent pixel rows other than the first pixel row, the first and second preliminary discharge pulses 22a or 22b are not deleted, reduced, or blunted, but instead of the second or subsequent pixel rows. Even if the first pre-discharge pulse 22a or the second pre-discharge pulse 22b in one pixel row is deleted, reduced or dulled, the pre-discharge in another pixel row can be weakened due to the influence of the discharge in the adjacent row. Further, not only in the first pixel row but also in a plurality of pixel rows, a strong pre-discharge is generated by superimposing the first pre-discharge pulse 22a and the second pre-discharge pulse 22b. The first pre-discharge pulse 22a or the second pre-discharge pulse 22b may be deleted, reduced, or blunted in a row other than the pixel row to be generated. For example, the first pre-discharge pulse 22a or the second pre-discharge pulse 22b is deleted, reduced, or reduced in the second to (m-1) th pixel rows except the first (first) pixel row and the m-th (final) pixel row. Or it can be blunted.
[0053]
Furthermore, for a pixel row where a strong preliminary discharge occurs, a large amount of light emission due to the strong preliminary discharge is achieved by combining techniques such as not applying a phosphor and forming a visible light opaque layer to block light. Can be reduced.
[0054]
A fourth embodiment of the present invention will be described. FIG. 5 is a timing chart showing a driving waveform applied to each electrode during a subfield period according to the fourth embodiment of the present invention. In this embodiment, according to the first to third embodiments, a strong and reliable pre-discharge is generated, and a pre-discharge is induced in the first pixel row which is a seed for inducing the pre-discharge in other pixel rows. Write discharge is always performed at the beginning of the scanning period after the discharge period. In the second and subsequent pixel rows, writing is selectively performed in accordance with video information as in the related art. In the first to third embodiments of the present invention, since only a weak preliminary discharge is generated in the second to mth pixel rows, the generation of the selective write discharge in the subsequent scanning period uses the strong preliminary discharge. May be somewhat unstable compared to the conventional driving method. Thus, in the present embodiment, the discharge control is ensured by utilizing the effect of the increase in the probability of occurrence of the discharge due to the influence of the adjacent discharge also for the write discharge. A write discharge is forcibly generated in the first pixel row, and the probability of occurrence of a selective write discharge in the second pixel row is improved by utilizing the effect of the adjacent discharge. Also in the third and subsequent pixel rows, the probability of occurrence of a write discharge can be improved by utilizing the effect of the write discharge in an adjacent pixel row.
[0055]
Further, a driving method in which a surface writing pulse is applied to the common electrode 13 when a scanning pulse is applied and a data pulse is not applied, and thus a weak surface discharge is generated by the scanning pulse 24 and the surface writing pulse even in a pixel which is not selected, or When a scan pulse is applied, a reference potential or a predetermined bias potential is applied to the data electrode 19, and the data pulse is not applied. Therefore, even in a pixel which is not selected, the subsequent sustain discharge is caused between the scan electrode 12 and the data electrode 19. When combined with a driving method that generates a weak opposing discharge that cannot be performed, a discharge occurs when a scan pulse is applied to all pixels.Therefore, in all pixels, a write discharge starts from the discharge of the nearest pixel to which the scan pulse was applied immediately before. The effect of improving the probability of occurrence can be obtained, and a high-contrast image can be obtained with a short scanning pulse width. It can be displayed on.
[0056]
Next, a fifth embodiment of the present invention will be described. In the present embodiment, the sustain pulse is not applied to the first pixel row serving as a base point for inducing a preliminary discharge in another pixel row according to the first to third embodiments. That is, the common electrode C₁And scanning electrode S₁No sustain pulse is applied. Further, the scanning electrode S₁, Neither the scan pulse nor the sustain erase pulse is applied. As a result, the first pixel row gives only the function as a base point for inducing a preliminary discharge to the second and subsequent pixel rows, and power consumption can be reduced by eliminating other driving pulses.
[0057]
In the first to fifth embodiments, the first pre-discharge pulse 22a has a negative polarity and the second pre-discharge pulse 22b has a positive polarity. On the contrary, the first pre-discharge pulse 22a has a positive polarity. Even if the second preliminary discharge pulse 22b has a negative polarity, the same effect can be obtained. Further, the pre-discharge and the pre-discharge erasure may be not a single pulse but a plurality of pulses. Further, the present invention can be similarly applied to a self-erasing drive in which the preliminary discharge erasing pulse 23 is deleted and the preliminary discharge erasing is performed by the discharge generated by the internal potential difference due to the accumulated wall charges at the end of the preliminary discharge pulses 22a and 22b. .
[0058]
【The invention's effect】
As described in detail above, according to the present invention, by generating a strong preliminary discharge only in some pixels, the preliminary discharge in other pixels can be weakened. , An AC discharge type plasma display having high contrast can be driven.
[Brief description of the drawings]
FIG. 1 is a timing chart showing driving waveforms related to pre-discharge and pre-discharge erasure according to a first example of the present invention.
FIG. 2 is a timing chart showing a driving waveform during a conventional preliminary discharge period.
FIG. 3 is a timing chart showing driving waveforms of a pre-discharge pulse and a pre-discharge erase pulse according to a second embodiment of the present invention.
FIG. 4 is a timing chart showing driving waveforms related to pre-discharge and pre-discharge erasure according to a third example of the present invention.
FIG. 5 is a timing chart showing a driving waveform applied to each electrode during a subfield period according to a fourth embodiment of the present invention.
FIG. 6 is a sectional view showing the structure of an AC-PDP.
FIG. 7 is a plan view schematically showing an electrode arrangement of an AC-PDP.
FIG. 8 is a schematic diagram showing an example of a drive voltage waveform applied to each electrode of a conventional PDP.
FIG. 9 is a timing chart showing a gradation display method of the plasma display panel.
[Explanation of symbols]
10; front substrate
11; rear substrate
12; scanning electrode
13; common electrode
15a, 15b; dielectric layer
16; protective layer
18; phosphor
19; data electrode
20; discharge space
21l; erase pulse
22a, 22b, 22c, 22d; preliminary discharge pulse
23: Predischarge erase pulse
24; scanning pulse
25, 26; sustain pulse
27; Data pulse

Claims (5)

At least one is a transparent two glass substrates, a plurality of row electrodes are formed on one of the glass substrates, and a plurality of column electrodes are formed on the other glass substrate separated by a predetermined gap Facing each other, filling a discharge gas in the gap, performing a pre-discharge of all pixels in a pre-discharge period, applying a scan pulse to the row electrode in a time-division manner in a scan period following the pre-discharge period, A driving method of an AC discharge type plasma display panel, in which a display pixel is selected by selectively applying a data pulse to a column electrode in synchronization with a pulse and a sustain discharge is performed only in the display pixel in a sustain period following the scanning period. ,
The rising of the leading edge of the pre-discharge pulse applied to the row electrodes except for the specific row electrode during the pre-discharge period is made slower than the leading edge of the pre-discharge pulse applied to the specific row electrode, and the specific A strong first preliminary discharge is generated in the pixels belonging to the row electrode, and a second preliminary discharge weaker than the first preliminary discharge is generated in the pixels belonging to the row electrodes other than the specific row electrode,
The specific row electrode is a row electrode to which the time-divided scan pulse is applied first , and when the time-divided scan pulse is first applied, the data pulse is applied to all the column electrodes. A driving method of an AC discharge type plasma display panel, wherein a display pixel selection discharge is generated in all pixels belonging to a row electrode to which the scanning pulse is applied first. At least one is a transparent two glass substrates, a plurality of row electrodes are formed on one of the glass substrates, and a plurality of column electrodes are formed on the other glass substrate separated by a predetermined gap Facing each other, filling a discharge gas in the gap, performing a pre-discharge of all pixels in a pre-discharge period, applying a scan pulse to the row electrode in a time-division manner in a scan period following the pre-discharge period, A driving method of an AC discharge type plasma display panel, in which a display pixel is selected by selectively applying a data pulse to a column electrode in synchronization with a pulse and a sustain discharge is performed only in the display pixel in a sustain period following the scanning period. ,
A pre-discharge pulse exceeding a discharge starting voltage of one polarity is applied to all of one row electrode of the pair of row electrodes during the pre-discharge period, and a specific row electrode among the other row electrodes of the pair of row electrodes is applied. A pre-discharge pulse of the other polarity is applied to the other row electrodes except for the specific row electrode, and no pre-discharge pulse is applied to the other row electrodes. , And a second preliminary discharge weaker than the first preliminary discharge is generated in the pixels belonging to the row electrodes except for the specific row electrode,
The specific row electrode is a row electrode to which the time-divided scan pulse is applied first , and when the time-divided scan pulse is first applied, the data pulse is applied to all the column electrodes. A driving method of an AC discharge type plasma display panel, wherein a display pixel selection discharge is generated in all pixels belonging to a row electrode to which the scanning pulse is applied first. At least one is a transparent two glass substrates, a plurality of row electrodes are formed on one of the glass substrates, and a plurality of column electrodes are formed on the other glass substrate separated by a predetermined gap Facing each other, filling a discharge gas in the gap, performing a pre-discharge of all pixels in a pre-discharge period, applying a scan pulse to the row electrode in a time-division manner in a scan period following the pre-discharge period, A driving method of an AC discharge type plasma display panel, in which a display pixel is selected by selectively applying a data pulse to a column electrode in synchronization with a pulse and a sustain discharge is performed only in the display pixel in a sustain period following the scanning period. ,
A pre-discharge pulse of one polarity is applied to all of the paired row electrodes during the pre-discharge period, and a pre-discharge pulse of the other polarity is applied to all the other row electrodes of the paired row electrodes. The rising edge of the leading edge of the pre-discharge pulse applied to the one row electrode except for the specific row electrode is made slower than the leading edge of the pre-discharge pulse applied to the specific row electrode. Generating a strong first preliminary discharge in the pixels belonging to the specific row electrode, and applying a second preliminary discharge weaker than the first preliminary discharge to the pixels belonging to the row electrodes other than the specific row electrode. raised calling, the particular row electrodes, said scanning pulse with time division is the row electrode is first applied,
When the time-division scanning pulse is first applied, the data pulse is applied to all the column electrodes, and a display pixel selection discharge is generated in all pixels belonging to the row electrode to which the scanning pulse is applied first. A method for driving an AC discharge type plasma display panel. In the scanning period, when applying the time-division scanning pulse, if a data pulse is applied to the column electrode, a display pixel selection discharge that shifts to a subsequent sustain discharge is generated, and the data is applied to the column electrode. 4. The method of driving an AC discharge type plasma display panel according to claim 1 , wherein when a pulse is not applied, a weak discharge that does not shift to a subsequent sustain discharge is generated. For the specific row electrode and a row electrode forming a pair with the specific row electrode, a part or all of a sustain pulse for generating the sustain discharge, the scan pulse, a sustain erase pulse for erasing the sustain discharge, The method of driving an AC discharge type plasma display panel according to any one of claims 1 to 4 , wherein at least one of them is not applied.

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