JP2008171670A - Plasma display panel and its driving method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a PDP capable of simultaneously attaining prevention of rise of discharge starting voltage, prevention of deterioration of discharge probability, and improvement of luminous efficiency. <P>SOLUTION: The plasma display panel is provided with a front substrate as well as a rear-face glass substrate 4 opposed to each other through a discharge space, a plurality of row electrode pairs (X, Y) fitted at a front glass substrate 1 side, a plurality of column electrodes forming a discharge cell in a discharge space at each crossing point with the row electrode pair, and a phosphor layer 7 fitted at a position facing the discharge cell between the column electrode D and the row electrode pair (X, Y). Discharge gas containing xenon gas by 10 volume% or more in the discharge space, and magnesium oxide is contained in the phosphor layer 7. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a structure of a plasma display panel and a driving method of the plasma display panel.

  A surface discharge type AC plasma display panel (hereinafter referred to as PDP) has a plurality of row electrode pairs extending in a row direction on one glass substrate of two glass substrates facing each other across a discharge space. A magnesium oxide film having a protective function of the dielectric layer and a secondary electron emission function into the unit light emitting region is formed on the surface of the dielectric layer by a vapor deposition method. A plurality of column electrodes extending in the column direction on the other glass substrate and arranged in a matrix at portions where the row electrode pairs and the column electrodes in the discharge space intersect each other ( Discharge cell) is formed.

In each discharge cell, phosphor layers that are color-coded into three primary colors of red, green, and blue are formed.
The discharge space of the PDP is filled with a discharge gas composed of a mixed gas of neon and xenon.

  In this PDP, reset discharge is simultaneously performed between a pair of row electrodes, and then, an address discharge is selectively generated between one row electrode and a column electrode to be adjacent to a discharge cell. The light emitting cells in which the wall charges are formed in the dielectric layer and the extinguished cells from which the wall charges in the dielectric layer have been erased are distributed on the panel surface, and then the sustaining is performed between the pair of row electrodes in the light emitting cell. A panel is produced by discharging a vacuum ultraviolet ray from the xenon gas mixed with the discharge gas in the discharge space, and the red, green, and blue phosphor layers are excited by the vacuum ultraviolet ray to emit light. An image is formed on the surface.

  Conventionally, in the PDP configured as described above, it is difficult to improve the light emission efficiency of the panel while preventing an increase in the discharge start voltage and a decrease in the discharge probability in each of the reset discharge, address discharge, and sustain discharge. Has been a long-standing challenge.

  In order to achieve such a problem for the PDP, conventionally, a discharge gas containing 10 volume percent or more of xenon gas is sealed in the discharge space between the front glass substrate and the rear glass substrate, A crystalline magnesium oxide layer containing a magnesium oxide crystal having a characteristic of performing cathodoluminescence emission having a peak in a wavelength range of 200 to 300 nm when excited by an electron beam is formed at a position facing the discharge cell C formed in (For example, refer to Patent Document 1).

  With this configuration, the conventional PDP can achieve to some extent both an increase in discharge start voltage and a reduction in discharge probability and an improvement in light emission efficiency.

  However, PDPs are required to further increase the discharge start voltage, prevent the discharge probability from decreasing, and improve the light emission efficiency as the screen becomes more fine in recent years. Yes.

JP 2006-269115 A

  One of the technical problems of the present invention is to meet the demand for the conventional PDP as described above.

  In order to solve the above-described problem, a PDP according to a first invention (the invention described in claim 1) is provided on a pair of substrates facing each other via a discharge space and on one substrate side of the pair of substrates. A plurality of row electrode pairs and a plurality of columns provided on the other substrate side so as to extend in a direction intersecting the row electrode pair and forming unit light-emitting regions in discharge spaces at respective intersections with the row electrode pair In a PDP comprising an electrode and a phosphor layer provided at a position facing a unit light emitting region between a column electrode and a row electrode pair, and the discharge gas is enclosed in a discharge space, the discharge gas has a volume of 10 A cathode containing a percentage of xenon gas and the phosphor layer including a secondary electron emission material, and the secondary electron emission material is excited by an electron beam and has a peak in a wavelength range of 200 to 300 nm.・ Luminescence emission It is characterized in that a magnesium oxide containing magnesium oxide crystal having the properties of causing.

  In order to achieve the above object, a method for driving a PDP according to a second invention (invention according to claim 8) includes a pair of substrates facing each other through a discharge space, and one substrate side of the pair of substrates. A plurality of row electrode pairs provided and the other substrate side are provided so as to extend in a direction intersecting the row electrode pairs, and unit light emitting regions are respectively formed in discharge spaces at respective intersections with the row electrode pairs. A plurality of column electrodes, and a phosphor layer including a secondary electron emission material provided at a position facing the unit light emitting region between the column electrodes and the row electrode pair, and 10 volume percent or more xenon in the discharge space A driving method of a PDP in which a discharge gas containing gas is enclosed, wherein a voltage pulse is applied to one row electrode constituting the row electrode pair, and the one row electrode to which this voltage pulse is applied is applied The potential of the column electrode is relatively negative By being set to the side, PDP driving method characterized by comprising the step of opposing discharge is generated between the column electrode and one row electrode.

  A PDP according to the present invention intersects a pair of substrates facing each other through a discharge space, a plurality of row electrode pairs provided on one substrate side of the pair of substrates, and a row electrode pair on the other substrate side. A plurality of column electrodes that are provided so as to extend in a direction to form a unit light emitting region in a discharge space at each intersection with the row electrode pair, and a position facing the unit light emitting region between the column electrode and the row electrode pair A PDP having a discharge layer filled with a discharge gas, wherein the discharge gas contains xenon gas of 10 volume percent or more, and the phosphor layer has a secondary electron emission material. And the secondary electron emission material includes a magnesium oxide crystal containing a magnesium oxide crystal having a characteristic of emitting cathode luminescence having a peak in a wavelength range of 200 to 300 nm when excited by an electron beam. The PDP is a Neshiumu, are the best embodiment.

  In the PDP driving method according to the present invention, in the PDP according to the above-described embodiment, a voltage pulse is applied to one of the row electrodes constituting the row electrode pair in the driving process, and one voltage pulse is applied to the other. It includes a process in which counter discharge is generated with the phosphor layer sandwiched between the column electrode and one row electrode by setting the potential of the column electrode relatively to the negative electrode side with respect to the row electrode. The driving method is the best embodiment.

  The PDP in the above embodiment can improve the light emission efficiency because the discharge gas contains xenon gas having a concentration of 10 volume percent or more. The phosphor layer formed at the position facing the unit light emitting region contains a secondary electron emission material, and between one row electrode and the column electrode of the row electrode pair located across the phosphor layer. When this discharge occurs, the cations generated from the discharge gas collide with the secondary electron emission material contained in the phosphor layer in the unit emission region, and this secondary electron is generated. Secondary electrons are emitted from the emitting material into the unit light emitting region, whereby a discharge that is performed next to the counter discharge between the one row electrode and the column electrode is present in the unit light emitting region. Since it is easily generated by secondary electrons, the discharge start voltage of this discharge is lowered and the discharge probability is improved, so that the rise of the discharge start voltage and the reduction of the discharge probability and the improvement of the luminous efficiency can be achieved at the same time. Will be able to

  Furthermore, when the counter discharge performed between the one row electrode and the column electrode is a reset discharge that initializes all the unit light emitting regions when the PDP is driven, the counter discharge is generated between the pair of substrates. Compared to the case where the reset discharge is performed by surface discharge between the row electrodes at a position close to the panel surface because the unit light emission region is separated from the substrate constituting the panel surface of the PDP. Therefore, the light emission due to the reset discharge recognized on the panel surface is reduced, so that the dark contrast is prevented from being lowered by the light emission not related to the gradation display of the video due to the reset discharge, and the dark contrast of the PDP is improved. Become figured.

  According to the driving method of the PDP in the above embodiment, the counter discharge performed between one row electrode and the column electrode is caused by applying a voltage pulse to one row electrode and applying this voltage pulse. As a result, the positive electrode generated from the discharge gas by this counter discharge is directed toward the column electrode on the negative electrode side. Since the secondary electron emission material collides with the secondary electron emission material contained in the phosphor layer, secondary electrons are efficiently emitted from the secondary electron emission material into the unit light emitting region.

  In the PDP and the driving method thereof in the embodiment, it is preferable that the secondary electron emission material is exposed in the unit light emitting region of the phosphor layer.

  As a result, the secondary electron emission material contained in the phosphor layer efficiently collides with the cation, and the secondary electrons can be more efficiently emitted into the unit light emitting region.

  In the PDP and the driving method thereof in the embodiment, as the form in which the secondary electron emission material is included in the phosphor layer, the form in which the secondary electron emission material is mixed with the fluorescent material constituting the phosphor layer, There is a form in which the electron emission material forms a layer and is laminated on the layer formed by the fluorescent material constituting the phosphor layer.

  In the PDP and the driving method thereof in the above embodiment, it is preferable to use magnesium oxide as a secondary electron emission material, whereby secondary electrons can be efficiently emitted from the phosphor layer into the unit light emitting region.

  Furthermore, in the PDP and the driving method thereof according to the above-described embodiment, as the secondary electron emitting material, cathode luminescence emission having a peak in the wavelength range of 200 to 300 nm, and further in the wavelength range of 230 nm to 250 nm is performed by the electron beam. It is preferable to use a magnesium oxide crystal having characteristics, in particular, a magnesium oxide containing a magnesium oxide single crystal produced by a gas phase oxidation method.

  As a result, the discharge intensity and discharge delay of the counter discharge performed between the one row electrode and the column electrode can be reduced, and the luminance of the PDP can be improved.

  In the PDP driving method of the embodiment, it is preferable to use the counter discharge performed between one row electrode and the column electrode as a reset discharge for initializing the unit light emitting region.

  As a result, the reset discharge is performed at substantially the central portion of the unit light emitting region away from the substrate constituting the panel surface of the PDP of the pair of substrates, so that the reset discharge is performed at the position close to the panel surface. Compared to the case where the surface discharge is performed between the two, the light emission due to the reset discharge recognized on the panel surface is reduced, and thus the dark contrast is lowered due to the light emission not related to the gradation display of the image due to the reset discharge. Therefore, the dark contrast of the PDP is improved.

  In the PDP driving method of the embodiment, a positive voltage pulse is applied to one row electrode and a negative voltage pulse is applied to the column electrode, or the column electrode is held at the ground potential. It is preferable to do so.

  As a result, a so-called negative column electrode discharge is generated between one row electrode and the column electrode, in which the cations generated from the discharge gas by the discharge are directed in the direction of the column electrode serving as the negative electrode.

  In the PDP driving method of this embodiment, the same polarity as the voltage pulse applied to one row electrode is applied to the other row electrode constituting the row electrode pair simultaneously with the application of the voltage pulse to one row electrode. It is preferable to apply a voltage pulse having a potential that does not generate a potential for generating a discharge with respect to one of the row electrodes.

  This prevents a discharge from occurring between the row electrodes of the pair of row electrodes, and ensures that a counter discharge is generated between one of the row electrodes and the column electrode.

  Further, in the PDP driving method of the above embodiment, it is preferable that the voltage pulse is applied to one of the row electrodes in such a manner that the voltage increases at a required increase rate from the start of application.

  As a result, the counter discharge is generated in a state where the rising voltage of the voltage pulse is not so large, so that the discharge intensity of the counter discharge can be reduced.

  1 to 3 show a first example of an embodiment of a PDP according to the present invention, FIG. 1 is a front view schematically showing the PDP in the first example, and FIG. 2 is a VV of FIG. 3 is a cross-sectional view taken along the line WW in FIG.

  The PDP shown in FIGS. 1 to 3 has a plurality of row electrode pairs (X, Y) in the row direction of the front glass substrate 1 (left and right direction in FIG. 1) on the back surface of the front glass substrate 1 as a display surface. They are arranged in parallel so as to extend.

  The row electrode X includes a transparent electrode Xa made of a transparent conductive film such as ITO formed in a T shape, and a metal film that extends in the row direction of the front glass substrate 1 and is connected to a narrow base end portion of the transparent electrode Xa. And the bus electrode Xb.

  Similarly, the row electrode Y is connected to the transparent electrode Ya made of a transparent conductive film such as ITO formed in a T-shape and the narrow base end portion of the transparent electrode Ya extending in the row direction of the front glass substrate 1. The bus electrode Yb is made of a metal film.

  The row electrodes X and Y are alternately arranged in the column direction (vertical direction in FIG. 1) of the front glass substrate 1, and the transparent electrodes Xa and Ya arranged in parallel along the bus electrodes Xb and Yb are respectively Extending to the paired row electrode side, the tops of the wide portions of the transparent electrodes Xa and Ya are opposed to each other via a discharge gap g having a required width.

  A dielectric layer 2 is formed on the back surface of the front glass substrate 1 so as to cover the row electrode pairs (X, Y). On the back surface of the dielectric layer 2, adjacent row electrode pairs (X , Y) protrudes on the back side of the dielectric layer 2 at a position facing the bus electrodes Xb and Yb positioned back to back and a position facing the region between the bus electrodes Xb and Yb positioned back to back. The raised dielectric layer 2A is formed so as to extend in parallel with the bus electrodes Xb and Yb.

  On the back side of the dielectric layer 2 and the raised dielectric layer 2A, cathode luminescence light emission (hereinafter referred to as CL light emission) having a peak in a wavelength range of 200 to 300 nm by being excited by an electron beam as described later. A magnesium oxide layer 3 including a magnesium oxide crystal (hereinafter referred to as a CL emission MgO crystal) is formed.

  On the other hand, on the display side surface of the rear glass substrate 4 arranged in parallel with the front glass substrate 1, the column electrode D is connected to the transparent electrodes Xa and Ya of each pair of row electrodes (X, Y). They are arranged in parallel at predetermined intervals so as to extend in a direction (column direction) orthogonal to the row electrode pair (X, Y) at the opposing positions.

A white column electrode protective layer 5 that covers the column electrode D is further formed on the display side surface of the rear glass substrate 4, and a partition wall 6 is formed on the column electrode protective layer 5.
The partition wall 6 includes a pair of horizontal walls 6A extending in the row direction at positions facing the bus electrodes Xb and Yb of each row electrode pair (X, Y), and a pair of horizontal walls 6A at an intermediate position between adjacent column electrodes D. A vertical wall 6B extending in the column direction is formed in a ladder shape, and each partition wall 6 is interposed through a gap SL extending in the row direction between the side walls 6A facing the back-to-back of other adjacent partition walls 6. Are arranged side by side in the row direction.

  And, by this ladder-shaped partition wall 6, the discharge space S between the front glass substrate 1 and the rear glass substrate 4 is opposed to the transparent electrodes Xa and Ya paired in each row electrode pair (X, Y). Each discharge cell C is formed in a square shape.

A phosphor layer 7 is formed on the side surfaces of the horizontal wall 6A and vertical wall 6B of the partition wall 6 facing the discharge cell C and the surface of the column electrode protection layer 5 so as to cover all five surfaces. The color of the body layer 7 is arranged so that the three primary colors of red, green, and blue are arranged in order in the row direction for each discharge cell C.
The configuration of the phosphor layer 7 will be described in detail later.

  The raised dielectric layer 2A is connected to the discharge cell C by contacting the display side surface of the horizontal wall 6A of the partition wall 6 with the magnesium oxide layer 3 covering the raised dielectric layer 2A (see FIG. 2). The gaps SL are closed, but the display side surface of the vertical wall 6B is not in contact with the magnesium oxide layer 3 (see FIG. 3), and a gap (communication portion) r is formed between them. The discharge cells C adjacent in the row direction communicate with each other through the gap r.

  A discharge gas containing xenon gas is enclosed in the discharge space S, and the concentration of the xenon gas in the discharge gas is set to be 10 volume percent or more.

The concentration of xenon gas in the discharge gas is set based on the results of experiments conducted by the inventors of the present invention, and for the PDP having the configuration of the present invention, the concentration of xenon gas in the discharge gas. As a result of measuring the luminous efficiency while changing the value, when the concentration of xenon gas is 10 volume percent or more, a value of 2 lm / W or more, which is the luminous efficiency of the CRT whose luminous efficiency is considered to be a currently useful value An experimental result was obtained.
FIG. 4 is an enlarged sectional view showing one discharge cell C in order to show the configuration of the phosphor layer 7.

  In FIG. 4, the phosphor layer 7 is composed of a mixture of red, green and blue particulate fluorescent material 7A and MgO (magnesium oxide) crystal 7B which is a secondary electron emission material. It is formed in a state of being disposed on the surface of the phosphor layer 7, that is, at a position exposed to the discharge space.

  FIG. 4 shows a state in which the MgO crystal 7B is arranged only on the surface of the phosphor layer 7. However, if the MgO crystal 7B is exposed to the discharge space, the MgO crystal 7B It may be mixed inside the phosphor layer 7.

  The MgO crystal 7B may be any form of MgO crystal as long as it has the property of emitting secondary electrons. However, the CL light-emitting MgO forming the magnesium oxide layer 3 described above. It is preferable to include a CL light-emitting MgO crystal having a characteristic of performing CL light emission having a peak in a wavelength range of 200 to 300 nm when excited by an electron beam, similar to the crystal body.

  The CL light-emitting MgO crystal is, for example, a magnesium single crystal obtained by vapor phase oxidation of magnesium vapor generated by heating magnesium (hereinafter, this magnesium single crystal is vapor phase-processed magnesium oxide single crystal). The vapor-phase-process magnesium oxide single crystal includes, for example, a magnesium oxide single crystal having a cubic single crystal structure as shown in the SEM photographic image of FIG. 5 and an SEM of FIG. As shown in the photographic image, a magnesium oxide single crystal having a structure in which cubic crystals are fitted into each other (that is, a cubic multiple crystal structure) is included.

  As will be described later, this vapor-phase-processed magnesium oxide single crystal contributes to improvement of discharge characteristics such as reduction of discharge delay of PDP.

  The vapor-phase-processed magnesium oxide single crystal has characteristics such as high purity, fine particles, and less aggregation of particles as compared with magnesium oxide obtained by other methods.

  In this example, a vapor phase magnesium oxide single crystal having an average particle diameter measured by the BET method of 2000 angstroms or more is used.

  In addition to the CL emission having a peak at 300 to 400 nm, the vapor phase method magnesium oxide single crystal having a large particle diameter has a CL within a wavelength range of 200 to 300 nm (particularly, around 235 nm and within 230 to 250 nm). It has the property that light emission is excited.

  CL emission having a peak in this wavelength range of 200 to 300 nm (especially, around 235 nm and within 230 to 250 nm) is not excited from ordinary vapor deposited MgO and has a peak at 300 to 400 nm as shown in FIG. Only the CL emission it has is excited.

  As can be seen from FIGS. 7 and 8, CL emission having a peak in the wavelength range of 200 to 300 nm (particularly 235 nm) increases in peak intensity as the particle size of the vapor-phase-grown magnesium oxide single crystal increases. .

The particle diameter (D _BET ) of the vapor phase magnesium oxide single crystal is calculated by the following equation from the BET specific surface area (s) measured by the nitrogen adsorption method.

D _BET = A / s × ρ
A: Shape counting (A = 6)
ρ: True density of magnesium FIG. 10 is a graph showing the correlation between the CL emission intensity of the vapor-phase magnesium oxide single crystal and the discharge delay of the PDP.

  From FIG. 10, since the vapor-phase method magnesium oxide single crystal has CL emission characteristics of 235 nm, a magnesium oxide layer containing the vapor-phase method magnesium oxide single crystal is formed in the discharge cell of the PDP. Thus, it can be seen that the delay of the discharge generated in the discharge cell is shortened, and further, that the discharge delay is shortened as the CL emission intensity at 235 nm is increased.

  From the above, the vapor phase magnesium oxide single crystal having an average particle diameter of 2000 angstroms or more measured by the BET method is used in the part facing the discharge cell of the PDP, so that the discharge probability and discharge delay of the PDP It can be seen that this can contribute to improvement of discharge characteristics such as reduction of discharge delay and improvement of discharge probability.

  FIG. 11 shows a case where a magnesium oxide layer disposed so as to face a PDP discharge cell is formed by applying a paste containing a vapor-phase magnesium oxide single crystal having an average particle diameter of 2000 to 3000 angstroms. FIG. 12 is a graph comparing discharge probabilities of discharge (for example, address discharge) performed between the magnesium oxide layers when formed by a conventional vapor deposition method and when not formed, and FIG. The discharge probabilities when the discharge pause time is 1000 μsec are shown.

  Further, in FIG. 13, similarly, a magnesium oxide layer disposed so as to face a PDP discharge cell is coated with a paste containing a vapor phase magnesium oxide single crystal having an average particle diameter of 2000 to 3000 angstroms. FIG. 14 is a graph comparing the discharge delay times when formed by the conventional vapor deposition method, when formed by the conventional vapor deposition method, and when not formed, and FIG. 14 shows the case where the discharge pause time is 1000 μsec in FIG. Each discharge delay time is shown.

11 to 14 show a case where the magnesium oxide layer includes a vapor-phase magnesium oxide single crystal having a multiple crystal structure.
From FIG. 11 to FIG. 14, the vapor phase magnesium oxide single crystal disposed in the portion facing the PDP discharge cell shows an improvement in the discharge probability of the PDP, the discharge delay, and the decrease in the pause time dependency of the discharge delay. It can be seen that it can greatly contribute to the improvement of the discharge characteristics.

  FIG. 15 is a graph showing the relationship between the particle size of the vapor phase magnesium oxide single crystal disposed in the portion facing the discharge cell and the discharge probability in the PDP.

  From FIG. 15, the larger the particle size of the vapor-phase-processed magnesium oxide single crystal, the higher the PDP discharge probability, and the particle size at which CL emission having a peak at 235 nm as described above is excited (in the example shown, 2000 angstroms). It can be seen that the discharge probability is greatly improved by a vapor-phase-grown magnesium oxide single crystal of 3,000 angstroms.

  As described above, the vapor phase magnesium oxide single crystal that performs CL emission having a peak in the wavelength range of 200 to 300 nm (particularly in the vicinity of 235 nm and 230 to 250 nm) contributes to the improvement of the discharge characteristics of the PDP. Is a vapor phase magnesium oxide single crystal having an energy level corresponding to its peak wavelength, and the energy level can trap electrons for a long time (several milliseconds or more). It is presumed that the initial electrons necessary for starting discharge are obtained by taking out.

  And the improvement effect of the discharge characteristic by this vapor phase method magnesium oxide single crystal increases as the intensity of CL emission having a peak in the wavelength range of 200 to 300 nm (especially in the vicinity of 235 nm and within 230 to 250 nm) increases. This is because, as described above, there is a correlation (see FIG. 8) between the CL emission intensity and the particle diameter of the vapor phase magnesium oxide single crystal.

  That is, in order to form a vapor phase magnesium oxide single crystal having a large particle size, it is necessary to increase the heating temperature when generating the magnesium vapor. For this reason, a flame in which magnesium and oxygen react with each other is required. As the length becomes longer and the temperature difference between the flame and the surroundings becomes larger, the vapor phase magnesium oxide single crystal having a larger particle size has a peak wavelength of CL emission as described above (for example, around 235 nm, 230 to This is because many energy levels corresponding to (within 250 nm) are formed.

In addition, compared with a general gas phase oxidation method, the amount of Mg evaporated per unit time is increased to increase the reaction region between Mg and O _2, and the reaction is generated with more O ₂ . In the vapor-phase-grown magnesium oxide single crystal, an energy level corresponding to the peak wavelength of CL emission as described above is formed.

  The cubic multi-crystal structure vapor-phase-processed magnesium oxide single crystal has many crystal plane defects, and the existence of this plane defect energy level contributes to the improvement of the discharge probability. Is done.

Next, a method for driving the PDP will be described.
This PDP is performed by the subfield method, and each subfield obtained by dividing a display period of one field into a plurality is divided into a reset discharge period in which a reset discharge for simultaneously initializing all discharge cells is performed, and a discharge in which light is emitted. An address discharge period in which an address discharge for selecting the cell C is performed, and a sustain discharge period in which a sustain discharge for emitting light for image formation is performed.

  In this PDP, the reset discharge performed in the first reset discharge period of each subfield is performed between the row electrode Y and the column electrode D by counter discharge.

  FIG. 16 is a pulse waveform diagram showing voltage pulses applied to the row electrode Y and the column electrode D during the reset discharge.

  In FIG. 16, not a rectangular pulse but a positive row electrode reset pulse Ry having a slow time constant and a large time constant is applied to the row electrode Y, and the row electrode reset pulse Ry is applied to the column electrode D. At the same time, a negative column electrode reset pulse Rd is applied.

  By applying the negative column electrode reset pulse Rd and the positive row electrode reset pulse Ry, the row electrode Y to the address electrode D are connected between the column electrode D serving as a cathode and the row electrode Y serving as an anode. A discharge in the direction (electron flow is from the column electrode D to the row electrode Y) is generated (hereinafter, the discharge generated when the column electrode D is set to the cathode side and the row electrode Y is set to the anode, Collectively referred to as negative electrode discharge).

  In FIG. 16, SP is a scan pulse applied to the row electrode Y during the address discharge period, and DP is a data pulse selectively applied to the column electrode D during the address discharge period. Address discharge is generated between the row electrode Y to which the scan pulse SP is applied and the column electrode D to which the data pulse DP is applied.

  In the PDP, a reset discharge is generated by a negative electrode discharge between the row electrode Y and the column electrode D facing each other with the discharge cell C interposed therebetween. The cation in C collides with the MgO crystal 7B, which is a secondary electron emission material mixed in the phosphor layer 7 located on the column electrode D side, toward the column electrode D serving as the negative electrode, Secondary electrons are emitted into the discharge cell C from the MgO crystal 7B.

  As a result, the address discharge performed in the address discharge period next to the reset discharge period is easily generated by the secondary electrons existing in the discharge cell C, and the discharge start voltage of the address discharge is lowered. I can do it.

  At this time, since the MgO crystal 7B is exposed on the surface of the phosphor layer 7, it efficiently collides with the cation and discharges the secondary electrons into the discharge cell C more efficiently. The discharge start voltage of the address discharge can be reduced.

  Further, in general, in the PDP, the reset discharge is accompanied by light emission, and the light emission by the reset discharge is light emission not related to the gradation display of the video. Is recognized on the panel surface, the dark contrast of the image is lowered. However, in the PDP, the reset discharge is performed by the counter discharge between the row electrode Y and the column electrode D, and this counter discharge is generated by the panel. Since the discharge is performed at the central portion of the discharge cell C away from the surface (the surface of the front glass substrate 1), compared with the case where the reset discharge is performed by surface discharge between the row electrodes at a position close to the panel surface, The light emission due to the recognized reset discharge is reduced, whereby the dark contrast of the displayed image can be improved.

  In the above description, the example (FIG. 16) in which the negative column electrode reset pulse Rd is applied to the column electrode D has been described, but in order to generate a reset discharge between the row electrode Y and the column electrode D. In other words, when the positive row electrode reset pulse Ry is applied to the row electrode Y, the column electrode D only needs to be set relatively to the negative side with respect to the positive row electrode Y. For example, as shown in FIG. 17, the column electrode D may be set to the ground (GND) potential, and moreover than the row electrode reset pulse Ry applied to the column electrode D to the row electrode Y. It may be a case where a positive voltage pulse is applied such that the potential is small and a discharge occurs between the row electrode Y and the column electrode D.

  In the following, the negative column electrode discharge is a positive polarity when the column electrode D is set to the ground (GND) potential at the reset discharge or when the column electrode D has a lower potential than the row electrode reset pulse Ry. This includes all cases where the potential of the column electrode D is set on the negative electrode side relative to the row electrode Y, such as when a voltage pulse is applied.

  Further, during this reset discharge, the row electrode X constituting the row electrode pair with the row electrode Y may be held at the ground (GND) potential during the reset discharge period, as shown in FIG. As described above, a voltage pulse Rx having the same polarity as the row electrode reset pulse Ry applied to the Y electrode and not causing a potential difference with the row electrode Y may be applied. .

  This prevents a potential difference that generates a discharge between the row electrodes X and Y constituting the row electrode pair while the reset discharge is generated, so that the reset discharge is reliably performed between the row electrode Y and the column. Only the counter discharge between the electrodes D can be achieved, and the dark contrast of the display image can be further improved.

  In the PDP, a CL light-emitting MgO crystal having a characteristic that the MgO crystal 7B mixed in the phosphor layer 7 emits CL having a peak in a wavelength range of 200 to 300 nm when excited by an electron beam as described above. The CL emission MgO is higher than that of a normal MgO crystal having no CL emission characteristic (hereinafter, this MgO crystal having no CL emission characteristic is referred to as a normal MgO crystal). Due to the characteristics described with reference to FIGS. 7 to 15 of the crystal, the discharge delay time is shortened, and furthermore, a voltage pulse having a large time constant and a gradual rise is applied to the row electrode Y, whereby dark contrast is reduced. The discharge intensity of the reset discharge that causes the decrease is reduced, and the dark contrast of the PDP is greatly improved.

  Further, when the CL light-emitting MgO crystal is included in the phosphor layer 7 and mixed with the MgO crystal 7B, the PDP is discharged from the CL light-emitting MgO crystal in the phosphor layer 7 by the reset discharge. The initial electrons are emitted in the inside, and the discharge delay of the reset discharge is further shortened by the initial electrons, and the priming effect is maintained for a long time, so that the address discharge generated after the reset discharge is further accelerated.

  As shown in FIG. 4, the PDP is disposed at a position where the CL light-emitting MgO crystal mixed with the phosphor layer 7 is exposed in the discharge cell C on the surface of the phosphor layer 7. Since the initial electrons can be efficiently discharged into the discharge cell C without being obstructed by the phosphor particles in the phosphor layer 7, the discharge start voltage of the address discharge can be further reduced.

  FIG. 19 shows a case where a voltage pulse of the form shown in FIG. 17 is applied to the row electrode Y and the column electrode D in a PDP in which the MgO crystal 7B mixed with the phosphor layer 7 of the PDP includes a CL light emitting MgO crystal. FIG. 20 is an oscilloscope waveform diagram showing the discharge intensity when the reset discharge is performed by a negative electrode discharge. FIG. 20 is a diagram showing the row electrode and the column electrode in the conventional PDP in which the phosphor layer is formed only of the fluorescent material. FIG. 18 is an oscilloscope waveform diagram showing discharge intensity when reset discharge is performed by applying a voltage pulse of the form shown in FIG.

  Note that the horizontal axis (time) of FIGS. 19 and 20 shows 1 ms on 10 scales in FIG. 20, whereas in FIG. 19, the discharge intensity of the reset discharge is very small, so 0.1 ms on 10 scales. 20 and is displayed on a scale 10 times that in the case of FIG. 20, and the scale of the vertical axis (discharge intensity) in FIG. 19 is also displayed on a scale 10 times that in FIG.

  Comparing FIG. 19 and FIG. 20, in FIG. 19, the discharge intensity of the reset discharge (negative electrode discharge) is very weak (about 1/40 to 1/50) compared to the case of FIG. In contrast to the discharge time being within about 0.04 ms, in the case of FIG. 20, it can be seen that the discharge intensity of the reset discharge is strong and the discharge time is over a long time of 1 ms or more.

  Accordingly, in the case of FIG. 20, the discharge intensity and the discharge delay are large, whereas in the case of FIG. 19, the discharge intensity and the discharge delay are greatly reduced. In the PDP of FIGS. It can be seen that mixing the CL light-emitting MgO crystal as the MgO crystal 7B with the body layer 7 further improves the dark contrast by reducing the discharge intensity and the discharge delay time.

  In FIG. 19, the discharge intensity decreases because the CL light-emitting MgO crystal has the effect of improving the discharge delay as described above, and this CL light-emitting MgO crystal is mixed with the phosphor layer 7. As a result, the discharge time of the reset discharge is greatly shortened to within about 0.04 ms, and the time constant as shown in FIGS. This is considered to be because, when a large voltage pulse is applied, the reset discharge ends when the voltage value in the middle of the rise of the voltage pulse applied to the row electrode Y is small.

  FIG. 21 shows a case where a voltage pulse with a large time constant and a slow rise is applied to the row electrode Y in the PDP in which the phosphor layer 7 of the PDP in FIGS. 1 to 3 includes a CL light-emitting MgO crystal as the MgO crystal 7B. The measurement result of the discharge delay time when the negative electrode discharge is generated is shown.

  The horizontal axis of FIG. 21 indicates the mixing ratio (weight percent) of the MgO crystal containing the CL emission MgO crystal to the fluorescent material, and the vertical axis indicates the discharge delay time.

  Here, the numerical value indicating the discharge delay on the vertical axis in FIG. 21 is a value normalized by setting the discharge delay to 1.0 when the mixing ratio of the MgO crystal is 5%.

  From FIG. 21, it can be seen that as the mixing ratio of the MgO crystal to the fluorescent material in the phosphor layer 7, that is, the mixing ratio of the CL light-emitting MgO crystal is larger, the discharge delay of the negative electrode discharge is decreased. It can be seen that the effect of shortening the discharge delay time due to is great.

  As described above, according to FIG. 19, a CL light emitting MgO crystal is mixed as the MgO crystal 7B with the phosphor layer 7 of the PDP of FIGS. 1 to 3, and a voltage pulse with a large time constant and a slow rise is applied to the row electrode Y. As a result, the discharge delay of the reset discharge is reduced, the discharge intensity is further reduced, and the dark contrast of the PDP is greatly improved.

  When the same measurement was performed on a PDP in which only normal MgO crystals that are not CL light-emitting MgO crystals were mixed in the state of FIG. 4 in the phosphor layer, the same results as in FIG. 20 were obtained, as described above. Although the effect of reducing the discharge start voltage and the improvement of the dark contrast by the secondary electron emission can be obtained, the effect of improving the discharge delay and the discharge intensity cannot be obtained.

  The reason is that an ordinary MgO crystal that is not a CL light-emitting MgO crystal has a secondary electron emission function, but an energy level corresponding to a peak wavelength region of 230 to 250 nm like a CL light-emitting MgO crystal. It is presumed that the electrons cannot be trapped for a long period of time and the initial electrons taken out to the discharge space when a voltage pulse is applied cannot be sufficiently obtained.

  The PDP has the effect of improving the brightness of the PDP in addition to the effect of improving the dark contrast as described above by mixing the phosphor layer 7 with the CL light-emitting MgO crystal as the MgO crystal 7B. .

  That is, during the sustain discharge period of the subfield, a sustain discharge due to surface discharge is generated between the row electrodes X and Y of the row electrode pair in the discharge cell C selected by the address discharge performed in the previous address discharge period. However, the sustain discharge generates vacuum ultraviolet rays of 146 nm and 172 nm from xenon in the discharge gas, and the vacuum ultraviolet rays excite the CL emission MgO crystal in the phosphor layer 7 to emit PL light (photoluminescence). By emitting light, ultraviolet rays having a peak at 230 to 250 nm (hereinafter referred to as PL ultraviolet rays) are generated.

  The PL ultraviolet light further excites the fluorescent material 7A in the phosphor layer 7, so that the brightness of the PDP is improved as compared with the case where only the normal MgO crystal is mixed in the phosphor layer.

  When CL phosphorescent MgO crystal is mixed in the phosphor layer 7 as the MgO crystal 7B, the brightness improvement effect of the PDP as described above is exhibited for the following reason.

  That is, in general, MgO crystals have a characteristic of absorbing vacuum ultraviolet rays generated from xenon in the discharge gas without being transmitted by discharge, and are therefore not normally CL light-emitting MgO crystals, for example. When only the MgO crystal is mixed in the phosphor layer, the vacuum ultraviolet ray generated from the discharge gas xenon is absorbed by the MgO crystal, and the amount of the vacuum ultraviolet ray irradiated to the phosphor particles around the MgO crystal As a result, the brightness of the PDP is reduced as compared with the case where the phosphor layer 7 is formed only of the fluorescent material.

  On the other hand, when the phosphor layer 7 contains and mixes a CL light-emitting MgO crystal as the MgO crystal 7B, the CL light-emitting MgO crystal absorbs vacuum ultraviolet rays generated from xenon in the discharge gas. After absorption, PL light is emitted by this vacuum ultraviolet ray, and PL ultraviolet ray having a peak wavelength at 230 to 250 nm is emitted.

  Since this PL ultraviolet light excites the phosphor 7A in the phosphor layer 7 to emit light, there is no possibility that the luminance is reduced by mixing only ordinary MgO crystals in the phosphor layer 7 as described above. The fluorescent material 7A of the phosphor layer 7 is also excited by PL ultraviolet rays generated from the CL emission MgO crystal in addition to the vacuum ultraviolet rays generated from the discharge gas xenon, so that the visible light amount generated from the phosphor layer 7 is Compared with the case where the mixed MgO crystal 7B is only a normal MgO crystal other than the CL light-emitting MgO crystal, the brightness of the PDP is greatly increased.

  Furthermore, since the CL light-emitting MgO crystal is mixed with the fluorescent material 7A in the phosphor layer 7 and is positioned immediately next to the phosphor particles, the PL ultraviolet rays generated from the CL light-emitting MgO crystal are efficiently reflected by the fluorescent material. 7A is irradiated to further increase the brightness of the PDP.

  In the above, the voltage of the form in which the row electrode reset pulse applied to the row electrode Y at the time of the reset discharge increases smoothly while changing the rising slope as shown in FIGS. The example of the pulse has been described, but in addition to this, the row electrode reset pulse is a voltage pulse R1y in a form of increasing linearly with a constant rising slope as shown in FIG. Also good.

  Also in this case, it is possible to obtain an effect of improving dark contrast, which is almost the same as the case where the row electrode reset pulse is a voltage pulse having a form as shown in FIGS.

  As in the case of FIG. 18, when a voltage pulse is applied to the other row electrode X constituting the row electrode pair simultaneously with the application of the row electrode reset pulse to the row electrode Y, it is shown in FIG. As described above, it is preferable to apply a voltage pulse R1x having the same polarity and the same waveform as the row electrode reset pulse R1y applied to the row electrode Y.

  As a result, the reset discharge can be reliably generated only between the row electrode Y and the column electrode D.

  In the above description, the configuration in which reset discharge is performed between the row electrode Y and the column electrode D has been described as an example. However, the PDP is applied with a row electrode reset pulse to the X electrode, A configuration in which reset discharge is performed between the row electrode X and the column electrode D may be employed.

  As described above, the PDP can achieve high luminous efficiency by containing 10 volume percent or more xenon gas in the discharge gas, and usually starts discharge when the concentration of xenon gas in the discharge gas is increased. While the voltage rises and the discharge probability decreases, the phosphor layer 7 is excited by an electron beam and has a characteristic of performing cathode luminescence emission having a peak in the wavelength range of 200 to 300 nm. When the magnesium oxide containing the body is mixed while being exposed to the discharge cell C, the discharge start voltage is lower than that of the conventional PDP and the discharge probability is increased. Can be achieved at the same time to prevent further deterioration and luminous efficiency, and also improve the dark contrast Door can be.

  Particularly, in the PDP, a negative electrode discharge is performed between the row electrode Y and the column electrode D, and the phosphor layer 7 disposed on the back glass substrate 4 side is mixed with magnesium oxide containing magnesium oxide crystals. Since the priming particles are released from the magnesium oxide into the discharge cell C at a position close to the column electrode D, an increase in the discharge start voltage due to the discharge gas having a high xenon concentration is further suppressed.

  FIG. 24 is a sectional view showing a second example of the embodiment of the PDP according to the present invention.

  The phosphor layer of the PDP of the first embodiment described above is formed by mixing a phosphor material and MgO crystal as a secondary electron emission material, whereas the PDP in the second embodiment is a phosphor layer. 17 is formed by stacking an MgO crystal layer 17B formed of MgO crystals as a secondary electron emission material on a fluorescent material layer 17A formed of the fluorescent material, and the MgO crystal layer 17B is exposed to the discharge cell C. It has the composition which is.

  The MgO crystal layer 17B may be formed by spreading MgO crystals on the fluorescent material layer 17A, or a thin film made of MgO crystals may be formed and laminated on the fluorescent material layer 17A. .

  When a CL light-emitting MgO crystal is used as a secondary electron emission material for forming the MgO crystal layer 17B, the MgO crystal layer 17B has a CL light-emitting MgO crystal spread on the fluorescent material layer 17A. Formed by.

The configuration of the other parts of the PDP is substantially the same as in the first embodiment, and the same reference numerals are assigned to the same components as in the first embodiment.
This PDP is driven by the same method as in the first embodiment.

  That is, the reset discharge is performed by a counter discharge due to the negative electrode discharge between the column electrode D and the column electrode D when the row electrode reset pulse having the form as shown in FIG.

  Thus, as in the first embodiment, in the PDP in which the discharge cells are closed by the barrier ribs and the movement of the priming particles is restricted, the effect of improving the dark contrast of the PDP by the reset discharge being performed by the counter discharge. The secondary electrons released from the MgO crystal layer 17B into the discharge cell C by the reset discharge exhibit the effect of reducing the discharge start voltage of the next address discharge.

  When the MgO crystal layer 17B is formed by including the CL light emitting MgO crystal, the dark contrast is further improved by shortening the discharge delay and decreasing the discharge intensity as in the case of the first embodiment. This CL light emitting MgO crystal generates PL ultraviolet light by performing PL light emission by vacuum ultraviolet light generated from xenon in the discharge gas, and this PL ultraviolet light further excites the fluorescent material layer 17A of the phosphor layer 17. Thus, the luminance of the PDP can be increased.

  The PDP in each of the above embodiments has a pair of substrates opposed via a discharge space, a plurality of row electrode pairs provided on one substrate side of the pair of substrates, and a row electrode pair on the other substrate side. A plurality of column electrodes which are provided so as to extend in the intersecting direction and form unit light-emitting regions in the discharge spaces at the respective intersections with the row electrode pairs, and unit light-emitting regions between the column electrodes and the row electrode pairs. A discharge layer containing 10% or more by volume of xenon gas in the discharge space, and the phosphor layer contains a secondary electron emission material. The PDP according to the embodiment, wherein the secondary electron emission material is magnesium oxide including a magnesium oxide crystal having a characteristic of performing cathode luminescence emission having a peak in a wavelength range of 200 to 300 nm when excited by an electron beam. In the PDP driving method of each of the above embodiments, a voltage pulse is applied to one of the row electrodes constituting the row electrode pair in this PDP, and the voltage pulse By setting the potential of the column electrode relatively to the negative electrode side with respect to one of the row electrodes to which is applied, a counter discharge is generated with the phosphor layer sandwiched between the column electrode and one of the row electrodes. The driving method according to the embodiment including the process is the embodiment of the superordinate concept.

  The PDP in this embodiment can improve the light emission efficiency because the discharge gas contains xenon gas having a concentration of 10 volume percent or more. The phosphor layer formed at the position facing the unit light emitting region contains a secondary electron emission material, and between one row electrode and the column electrode of the row electrode pair located across the phosphor layer. As a result of the counter discharge being performed, the cations generated from the discharge gas in the unit emission region collide with the secondary electron emission material contained in the phosphor layer, and the secondary electrons are generated. Secondary electrons are emitted from the emitting material into the unit light emitting region, whereby a discharge that is performed next to the counter discharge between the one row electrode and the column electrode is present in the unit light emitting region. Since it is easily generated by secondary electrons, the discharge start voltage of this discharge is lowered and the discharge probability is improved, so that the rise of the discharge start voltage and the reduction of the discharge probability and the improvement of the luminous efficiency can be achieved at the same time. Will be able to

  According to the PDP driving method in the above embodiment, the counter discharge performed between one row electrode and the column electrode is such that a voltage pulse is applied to one row electrode, and the potential of the column electrode is changed to a voltage pulse. Is generated on the negative electrode side relative to one of the row electrodes to which cation is applied, so that the cations generated from the discharge gas by this counter discharge are directed toward the column electrode on the negative electrode side. Since the secondary electron emission material collides with the secondary electron emission material contained in the phosphor layer, secondary electrons are efficiently emitted from the secondary electron emission material into the unit light emitting region.

It is a front view which shows the 1st Example of embodiment of this invention. It is sectional drawing in the VV line of FIG. It is sectional drawing in the WW line of FIG. It is sectional drawing which shows the structure of the fluorescent substance layer of the Example. It is a figure which shows the SEM photograph image of the magnesium oxide single crystal which has a cubic single crystal structure. It is a figure which shows the SEM photograph image of the magnesium oxide single crystal which has a cubic multiple crystal structure. It is a graph which shows the relationship between the particle size of a magnesium oxide single crystal, and the wavelength and intensity | strength of CL light emission. It is a graph which shows the relationship between the particle size of a magnesium oxide single crystal, and the peak intensity of CL light emission of 235 nm. It is a graph which shows the state of the wavelength of CL light emission from the magnesium oxide layer by a vapor deposition method. It is a graph which shows the relationship between the peak intensity of CL light emission of 235 nm from a magnesium oxide single crystal body, and a discharge delay. It is a graph which shows the relationship between the magnesium oxide single crystal body of a multicrystal structure, and a discharge probability. It is a table | surface figure which shows the relationship between the magnesium oxide single crystal of the same multicrystal structure, and a discharge probability. It is a graph which shows the relationship between the magnesium oxide single crystal body of the same multicrystal structure, and discharge delay. It is a table | surface figure which shows the relationship between the magnesium oxide single crystal body of the same multicrystal structure, and discharge delay. It is a graph which shows the relationship between the particle size of a magnesium oxide single crystal, and a discharge probability. In the Example, it is a pulse waveform diagram which shows the form of the voltage pulse applied to a row electrode and a column electrode. It is a pulse waveform diagram showing another example of the same voltage pulse. It is a pulse waveform diagram showing still another example of the same voltage pulse. It is an oscilloscope waveform diagram which shows the discharge intensity when CL light emission MgO crystal is contained in the fluorescent substance layer in the Example. It is an oscilloscope waveform diagram which shows the discharge intensity in case a fluorescent substance layer is formed only with fluorescent material. It is a graph which shows the relationship between the mixing ratio of CL light emission MgO crystal | crystallization contained in a fluorescent substance layer, and a discharge delay in the Example. In the Example, it is a pulse waveform diagram which shows the other form of the voltage pulse applied to a row electrode. It is a pulse waveform diagram showing another example of the same voltage pulse. It is sectional drawing which shows the 2nd Example of embodiment of this invention.

Explanation of symbols

1 ... Front glass substrate (one substrate)
4 ... Back glass substrate (the other substrate)
7, 17 ... Phosphor layer 7A ... Fluorescent material 7B ... MgO crystal (secondary electron emission material)
17A: Fluorescent material layer 17B: MgO crystal layer (secondary electron emission material)
C: Discharge cell (unit emission region)
Rx, R1x ... Voltage pulse Ry, R1y ... Row electrode reset pulse (voltage pulse)
Rd ... Column electrode reset pulse (voltage pulse)
X: Row electrode (the other row electrode)
Y: Row electrode (one row electrode)
D: Column electrode

Claims (21)

A pair of substrates facing each other through the discharge space, a plurality of row electrode pairs provided on one substrate side of the pair of substrates, and extending in a direction intersecting the row electrode pair on the other substrate side A plurality of column electrodes each forming a unit light emitting region in a discharge space at each intersection with a row electrode pair, and a phosphor provided at a position facing the unit light emitting region between the column electrode and the row electrode pair In a plasma display panel comprising a layer and having a discharge gas sealed in a discharge space,
The discharge gas comprises 10 volume percent or more xenon gas;
The phosphor layer contains a secondary electron emission material, and this secondary electron emission material is excited by an electron beam to emit cathode luminescence having a peak in a wavelength range of 200 to 300 nm. Magnesium oxide containing magnesium crystals,
A plasma display panel characterized by that.   The plasma display panel according to claim 1, wherein the secondary electron emission material is exposed in a unit light emitting region.   The plasma display panel according to claim 1, wherein the secondary electron emission material is mixed with a fluorescent material constituting a phosphor layer.   The plasma display panel according to claim 1, wherein the secondary electron emission material forms a layer and is laminated on a layer formed by a fluorescent material constituting the phosphor layer.   2. The plasma display panel according to claim 1, wherein the magnesium oxide crystal has a characteristic of performing cathodoluminescence emission having a peak within 230 nm to 250 nm.   The plasma display panel according to claim 1, wherein the magnesium oxide crystal is a magnesium oxide single crystal produced by a gas phase oxidation method.   The plasma display panel according to claim 1, wherein the magnesium oxide crystal has a particle size of 2000 angstroms or more. A pair of substrates facing each other through the discharge space, a plurality of row electrode pairs provided on one substrate side of the pair of substrates, and extending in a direction intersecting the row electrode pair on the other substrate side A plurality of column electrodes each forming a unit light emitting region in a discharge space at each intersection with the row electrode pair, and two column electrodes provided at a position facing the unit light emitting region between the column electrode and the row electrode pair. A method for driving a plasma display panel comprising a phosphor layer containing a secondary electron emission material, wherein a discharge gas containing 10 volume percent or more xenon gas is sealed in a discharge space,
A voltage pulse is applied to one row electrode constituting the row electrode pair, and the potential of the column electrode is set relatively to the negative side with respect to the one row electrode to which the voltage pulse is applied. A method for driving a plasma display panel, comprising a step of generating a counter discharge between a column electrode and one row electrode.   9. The method of driving a plasma display panel according to claim 8, wherein the counter discharge is a reset discharge for initializing a unit light emitting region.   9. The method of driving a plasma display panel according to claim 8, wherein a positive voltage pulse is applied to the one row electrode and a negative voltage pulse is applied to the column electrode.   9. The method of driving a plasma display panel according to claim 8, wherein a positive voltage pulse is applied to the one row electrode, and the column electrode is held at a ground potential.   The voltage pulse having the same polarity as the voltage pulse applied to the one row electrode is applied to the other row electrode constituting the row electrode pair simultaneously with the application of the voltage pulse to the one row electrode. A driving method of the plasma display panel as described.   9. The method of driving a plasma display panel according to claim 8, wherein the voltage pulse is applied to one of the row electrodes in such a manner that the voltage increases at a required increase rate from the start of application.   9. The method of driving a plasma display panel according to claim 8, wherein the secondary electron emission material is exposed in a unit light emitting region of the phosphor layer.   9. The method of driving a plasma display panel according to claim 8, wherein the secondary electron emission material is mixed with a fluorescent material constituting a phosphor layer.   9. The method of driving a plasma display panel according to claim 8, wherein the secondary electron emission material is laminated on a layer formed of a fluorescent material forming a phosphor layer by forming a layer.   The method for driving a plasma display panel according to claim 8, wherein the secondary electron emission material is magnesium oxide.   18. The method for driving a plasma display panel according to claim 17, wherein the magnesium oxide includes a magnesium oxide crystal having a characteristic of performing cathodoluminescence emission having a peak in a wavelength range of 200 to 300 nm when excited by an electron beam. .   19. The method for driving a plasma display panel according to claim 18, wherein the magnesium oxide crystal has a characteristic of performing cathode luminescence emission having a peak in the range of 230 nm to 250 nm.   19. The method for driving a plasma display panel according to claim 18, wherein the magnesium oxide crystal is a magnesium oxide single crystal produced by a gas phase oxidation method.   The plasma display panel according to claim 18, wherein the magnesium oxide crystal has a particle size of 2000 angstroms or more.