JP2008108461A - Plasma display panel - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To solve a problem that a scanning line must be driven in a state of being split vertically into two, in order to improve the delay of discharge in a PDP. <P>SOLUTION: The PDP is provided with a row electrode pair (X1, Y1) and a column electrode D disposed between a front glass substrate 1 and a rear glass substrate 6 opposed through a discharge space S, for generating a discharge in a discharge cell C1, and a dielectric layer 3 for coating the row electrode pair (X1, Y1). An electron emitting material layer 5 including an electron emitting material for emitting electrons in the discharge cell C1 by means of the discharge is patterned on a region opposed to the row electrode Y1 serving as a negative electrode at least when generating the discharge, out of regions opposed to the row electrodes X1, Y1 constituting the row electrode pair (X1, Y1) on the side of facing the discharge cell C1 of the dielectric layer 3. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a configuration of a plasma display panel.

  A surface discharge type AC plasma display panel (hereinafter referred to as PDP) is generally arranged in a row direction on one glass substrate of two glass substrates facing each other across a discharge space in which a discharge gas is sealed. The row electrode pairs extending in the column direction are arranged side by side, the column electrodes extending in the column direction are arranged in the row direction on the other glass substrate, and the matrix is formed at the intersection of the row electrode pairs and the column electrodes in the discharge space. A unit light emitting region (discharge cell) is formed in a shape.

  In this PDP, the protective function of the dielectric layer and the secondary to the unit light emitting region are provided at a position facing the unit light emitting region on the dielectric layer formed to cover the row electrode and the column electrode. A magnesium oxide (MgO) film having an electron emission function is formed.

  It has been proposed that such a conventional PDP magnesium oxide film is formed by applying a paste mixed with magnesium oxide powder on a dielectric layer by a screen printing method (see, for example, Patent Document 1). .

  However, this conventional magnesium oxide film is formed by applying a paste mixed with polycrystalline single-leaf magnesium oxide purified by heat treatment of magnesium hydroxide by a screen printing method. The discharge characteristics of the PDP are almost the same as or slightly improved as the magnesium oxide film formed by the vapor deposition method.

  In recent years, PDPs for which the number of scanning lines for full high vision or the like has been significantly increased compared to the conventional ones have been commercialized in order to improve image quality.

  However, in such a PDP having an increased number of scanning lines, a discharge period such as an address discharge for selecting a discharge cell to emit light becomes longer at the time of driving, so that the scanning line is divided into two in the vertical direction. Thus, there is a problem that it must be driven.

JP-A-6-325696

  One object of the present invention is to solve the problems in the conventional PDP as described above.

  In order to achieve the above object, a PDP according to the present invention (the invention described in claim 1) is arranged between a pair of substrates facing each other via a discharge space and the pair of substrates to discharge in the discharge space. In a plasma display panel having a unit light emitting region formed in a discharge space, the side facing the unit light emitting region of the dielectric layer An electron-emitting material layer containing an electron-emitting material that emits electrons into the unit light-emitting region by discharge by the discharge electrode is disposed on at least a region facing the discharge electrode that becomes the cathode side when a discharge occurs in the region facing the discharge electrode of It is characterized by being patterned.

  The present invention includes a front substrate and a rear substrate that are opposed to each other through a discharge space, a row electrode pair and a column electrode that are disposed between the front substrate and the rear substrate and generate a discharge in the discharge space, and the row electrode pair. A discharge layer is formed in the discharge space, and at least discharge is generated in a region facing the row electrode constituting the row electrode pair on the side facing the discharge cell of the dielectric layer. A PDP in which an electron-emitting material layer containing an electron-emitting material that emits electrons into a discharge cell by a discharge is formed on a region facing the row electrode on the cathode side sometimes is the best embodiment.

  In the PDP in this embodiment, reset discharge, address discharge, and sustain discharge for image formation are performed in the discharge cell, and the electron emission material contained in the electron emission material layer is generated in the discharge cell during the discharge driving. Due to the generated discharge, secondary electrons continue to be emitted into the discharge space for a long time.

  The secondary electrons emitted from the electron emission material layer function as initial electrons for the next generated discharge, and shorten the discharge delay of the next generated discharge.

  Accordingly, for example, in a PDP having a large number of scanning lines on the screen such as full high vision, the discharge period of the address discharge performed between the cathode-side row electrode and the column electrode in order to select the discharge cell to emit light is reduced. It is prevented from becoming long, and it is not necessary to drive the scanning line by dividing the scanning line into upper and lower parts for shortening the discharge period, thereby preventing an increase in driver cost.

  As an example of the formation form of the electron-emitting material layer, the electron-emitting material layer is formed from the discharge gap in the column direction of at least one of the row electrodes that constitute the row electrode pair and are opposed to each other via the discharge gap. When patterning is performed in a region facing the distant portion, when patterning is performed in a region facing the bus electrode of the row electrode, each bus electrode of the row electrode positioned back to back of the adjacent row electrode pair and this Examples include a pattern formed in a non-display area of a panel where a portion between bus electrodes located back to back is located.

  When this electron-emitting material layer is formed in a region including a non-display region of the panel, white powder is used as the electron-emitting material forming the electron-emitting material layer, thereby emitting light in the discharge cell. Visible light incident on the non-display area of the panel is reflected in the discharge cell by the white electron emission material layer, and further reflected by the phosphor layer in the discharge cell. By being emitted from the front substrate, the light emission characteristics of the panel are improved and the luminance of the image is increased.

  As another example of the formation form of the electron-emitting material layer, the electron-emitting material layer is independently formed in an island shape for each discharge cell, and the size of the island-shaped electron-emitting material layer is Examples are set in accordance with the characteristics for each color of the fluorescent material forming the phosphor layer.

  In the case of this example, when an address discharge is generated through the phosphor layer, an amount corresponding to the influence on the discharge delay of the fluorescent materials of red, green and blue forming each phosphor layer. By causing secondary electrons to be emitted from the electron-emitting material layer into the discharge cells, variations in discharge delay among the discharge cells of the respective colors can be eliminated.

  Furthermore, as another example of the formation form of the electron emission material layer, the size of the electron emission material layer is larger than that of the electron emission material layer facing the bus electrode of one row electrode that generates a discharge with the column electrode. In this example, the electron emission material layer facing the bus electrode of the other row electrode is set to be larger.

  In this example, when an address discharge is generated between one row electrode on the scan electrode side and the column electrode among the row electrodes constituting the row electrode pair, the bus electrode of the scan electrode side row electrode is applied to the bus electrode. A secondary electron is emitted from the opposing electron emission material layer into the discharge cell to improve the discharge delay of this address discharge, and further, a scan formed at a position facing the bus electrode of the other row electrode on the common electrode side. An electron emission material layer larger than that on the electrode side can prevent erroneous discharge from occurring on the common electrode side and can increase the drive margin.

  Examples of the electron emission material contained in the electron emission material layer include 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. The magnesium crystal body preferably has a particle size of 2000 angstroms or more, and is preferably generated by vapor-phase oxidation of heated magnesium vapor.

  By using the magnesium oxide crystal as described above as an electron emission material, further improvement in discharge characteristics such as reduction in discharge delay of PDP is achieved.

  1 and 2 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 view of V1-V1 in FIG. It is sectional drawing in a line.

  In the PDP shown in FIGS. 1 and 2, a plurality of row electrode pairs (X1, Y1) are arranged 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 X1 is formed in a T shape by a bus electrode X1a made of a conductive layer having a black or dark color layer extending in the row direction of the front glass substrate 1 on the display surface side and a transparent conductive film such as ITO. In addition, the base end portion is configured by a plurality of transparent electrodes X1b that are connected to the equally spaced positions of the bus electrode X1a and protrude toward the row electrode Y1.

  Similarly, the row electrode Y1 is formed into a T shape by a bus electrode Y1a formed of a conductive layer having a black or dark color layer extending in a strip shape in the row direction parallel to the row electrode X1 and a transparent conductive film such as ITO. And a plurality of transparent electrodes X1b projecting toward the row electrode X1 with the base end portion connected to the equally spaced positions of the bus electrode Y1a.

  The row electrodes X1 and Y1 are alternately arranged in the column direction of the front glass substrate 1 (the vertical direction in FIG. 1), and the transparent electrodes X1b and Y1b arranged in parallel along the bus electrodes X1a and Y1a The tops of the wide portions of the transparent electrodes X1b and Y1b are opposed to each other via a discharge gap g1 having a required width, extending to the paired row electrode side.

  On the back surface of the front glass substrate 1, a row electrode pair (X1, Y1) adjacent to each other in the column direction extends between the bus electrodes X1a and Y1a back to back in the row direction along the bus electrodes X1a and Y1a. A black or dark light absorption layer (light shielding layer) 2 is formed.

  A dielectric layer 3 is formed on the back surface of the front glass substrate 1. The dielectric layer 3 covers the row electrode pair (X 1, Y 1), the light absorption layer 2, and the back surface of the front glass substrate 1.

  A thin film magnesium oxide layer (hereinafter referred to as a thin film magnesium oxide layer) 4 formed by vapor deposition or sputtering is further formed on the back side of the dielectric layer 3, and the thin film magnesium oxide layer 4 forms a dielectric layer. The entire back surface of 3 is covered.

  A light-shielding region including a base end portion where the bus electrode Y1a of the transparent electrode Y1b of the row electrode Y1 is connected to the light-absorbing layer 2 on the back surface of the thin-film magnesium oxide layer 4 (in the illustrated example, the light-absorbing layer in the column direction). 2 is an electron emission material layer extending in a strip shape in the row direction by an electron emission material as will be described later on a portion of the transparent electrode Y1b opposite to the bus electrode Y1a of the transparent electrode Y1b. 5 is formed.

  On the other hand, on the display side surface of the rear glass substrate 6 that is arranged in parallel with the front glass substrate 1 at a predetermined interval, the column electrode D is paired with each other of the row electrode pairs (X1, Y1). The electrodes are arranged in parallel at predetermined intervals so as to extend in a direction (column direction) orthogonal to the row electrode pair (X1, Y1) at a position facing the transparent electrodes X1b, Y1b.

  A white column electrode protective layer (dielectric layer) 7 covering the column electrode D is further formed on the display side surface of the rear glass substrate 6, and a partition wall 8 is formed on the column electrode protective layer 7. Has been.

  The barrier ribs 8 are arranged at the intermediate positions between the horizontal walls 8A extending in the row direction at positions facing the dielectric layer 2 formed between the adjacent row electrode pairs (X1, Y1) and the adjacent column electrodes D. A plurality of vertical walls 8B extending in the direction are formed in a substantially lattice shape.

  Due to the substantially lattice-shaped partition walls 8, the discharge space S between the front glass substrate 1 and the rear glass substrate 6 is a portion facing the transparent electrodes X1b and Y1b that are paired with each other in each row electrode pair (X1, Y1). Each discharge cell C <b> 1 is divided into squares.

  The display-side surface of the horizontal wall 8A of the partition wall 8 is brought into contact with the electron emission material layer 5 formed on the thin-film magnesium oxide layer 4 (see FIG. 2), and the gap between the discharge cell C1 and the gap SL is formed. Although each closed, the surface on the display side of the vertical wall 8B is not in contact with the electron emission material layer 5, and a gap is formed between them, and this gap is formed between adjacent discharge cells C1 in the row direction. Are in communication with each other.

  A phosphor layer 9 is formed on the side surfaces of the horizontal and vertical walls 8A and 8B of the barrier rib 8 facing the inside of the discharge cell C1 and the surface of the column electrode protection layer 7 so as to cover all five surfaces. The phosphor layer 9 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 C1.

  A discharge gas containing xenon is enclosed in the discharge space S.

  The electron emission material forming the electron emission material layer 5 is a cathode luminescence emission (CL) having a peak in a wavelength range of 200 to 300 nm (especially in the range of 230 to 250 nm, around 235 nm) when excited by an electron beam. And a magnesium oxide crystal having the property of emitting light.

  A magnesium oxide crystal having a characteristic of emitting CL light having a peak in a wavelength range of 200 to 300 nm when excited by this electron beam is, for example, vapor phase oxidation of magnesium vapor generated by heating magnesium. The obtained magnesium single crystal (hereinafter, this magnesium single crystal is referred to as a vapor-phase magnesium oxide single crystal) is included in the vapor-phase magnesium oxide single crystal. A structure in which a magnesium oxide single crystal having a cubic single crystal structure and a cubic crystal as shown in the SEM photographic image of FIG. 4 are fitted to each other (ie, a cubic multiple crystal structure) ) Magnesium oxide single crystal.

  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 in 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 embodiment, a vapor-phase magnesium oxide single crystal having an average particle size measured by the BET method of 500 angstroms or more (preferably 2000 angstroms or more) is used.

  This BET method is a method in which the BET specific surface area of a particle is measured by a nitrogen adsorption method, and the particle diameter of the particle is calculated by the following formula from this value.

D _BET = A / (s × ρ)
D _BET : Particle size
A: Shape counting (in the case of magnesium oxide single crystal, A = 6)
s: BET specific surface area
ρ: True density of magnesium When the above PDP is driven, reset discharge, address discharge, and sustain discharge for image formation are performed in the discharge cell C1.

  At the time of driving the PDP, the electron emission material forming the electron emission material layer 5 emits secondary electrons into the discharge space by the discharge generated in the discharge cell C1, and after the end of the discharge, the thin film magnesium oxide It has a characteristic of continuing to emit secondary electrons over a longer time than MgO forming the layer 4.

  The secondary electrons emitted from the electron emission material layer 5 function as initial electrons of the next generated discharge, and contribute to a reduction in discharge delay as will be described later.

  In the PDP, the electron emission material layer 5 includes bus electrodes X1a and Y1a located on the back side of adjacent row electrode pairs (X1, Y1) on the back surface of the thin film magnesium oxide layer 4, and the light absorption layer 2 located therebetween. The following effects are exhibited by being formed only in the region facing the.

  That is, in the PDP, when the number of scanning lines on the screen is increased as in full high vision or the like, an address discharge is performed between the row electrode X1 or Y1 and the column electrode D in order to select the discharge cell C1 to emit light. Since the discharge period becomes longer, it becomes necessary to divide the scanning line into upper and lower parts and drive it, which may increase the driver cost.

  In the PDP, the address discharge is generated between the column electrode D, with the base end portion facing the discharge cell C1 opposite to the discharge gap g1 side of the transparent electrode Y1b of the row electrode Y1 serving as a cathode. The

  Therefore, the electron emission material layer 5 is formed in the region where the address discharge is generated, and the emission of secondary electrons from the electron emission material layer 5 into the discharge cell C1 continues during the address discharge period. Therefore, for example, the discharge delay of each address discharge performed in the sub-field method is reduced, and the address discharge period is shortened.

  Therefore, even in a PDP having a large number of scanning lines such as full high-definition, it is possible to prevent the address discharge period from becoming longer than that of the conventional PDP. As a result, the driver cost can be reduced.

  Here, in order to increase the amount of secondary electrons emitted into the discharge space S, an electron emitting material layer is formed on the entire surface of the thin-film magnesium oxide layer 4 so that a portion of the electron emitting material facing the discharge cell C1 is formed. It is also conceivable to increase the amount.

  However, when the electron emission material is white powder, if the electron emission material layer is formed at a position facing the discharge cell C1, visible light generated from the phosphor layer 9 by the sustain discharge is emitted from the electron emission material layer. Scattered by the white electron emitting material, the transmittance is lowered, thereby reducing the brightness of the screen.

  In the PDP, since the electron emission material layer 5 is formed in the light-shielding region of the panel, the electron emission material layer 5 is increased in thickness without increasing the visible light transmittance. As a result, the amount of the electron-emitting material that forms the substrate can be increased, so that sufficient initial electrons (secondary electrons) necessary for shortening the discharge delay can be supplied to the discharge region of the address discharge.

  Further, in the PDP, when the electron emission material layer 5 is formed in the light shielding region of the panel, and the electron emission material forming the electron emission material layer 5 is a white powder, the phosphor layer during the sustain discharge Of visible light generated from the light 9, visible light incident on the light shielding region where the bus electrodes X 1 a and Y 1 a and the light absorption layer 2 are located is reflected by the white electron-emitting material layer 5 toward the discharge cell C 1. Further, the light is reflected by the phosphor layer 9 and the like in the discharge cell C1 and emitted from the front glass substrate 1, so that the light emission characteristics of the panel can be improved and the luminance of the screen can be increased.

  The electron-emitting material forming the electron-emitting material layer 5 generally tends to change in characteristics due to changes over time due to sputtering and reattachment of the thin-film magnesium oxide layer 4 that is the base of the electron-emitting material layer 5. In the PDP, since the electron emission material layer 5 is disposed in the light shielding region of the panel away from the discharge gap g1 between the transparent electrodes X1b and Y1b, the thin-film magnesium oxide layer 4 is sputtered and reattached in the display region of the panel. It is possible to improve the discharge delay of the address discharge while maintaining the secondary electron emission characteristic without being affected by the time-dependent change due to.

  Furthermore, since the PDP has no electron emission material layer formed in the display area of the panel, the sustain discharge generated through the discharge gap g1 between the transparent electrodes X1b and Y1b is accelerated more than necessary. In this way, it is possible to avoid the influence on the sustain discharge characteristics such that the voltage drop occurs due to the concentration of the discharge load.

  Next, the reason why the discharge delay is improved by the vapor phase magnesium oxide single crystal, which is one of the electron emitting materials forming the electron emitting material layer 5, will be described with reference to FIGS.

  As shown in FIGS. 5 and 6, the vapor phase magnesium oxide single crystal, which is an electron emission material, is irradiated with an electron beam when the particle size is large (in FIG. 5, 2000 angstrom or more). Then, it is excited by the electron beam and has a characteristic of performing CL emission having peaks in the wavelength range of 300 to 400 nm and in the range of 200 to 300 nm (particularly, around 235 nm in the range of 230 to 250 nm).

  As shown in FIG. 7, a characteristic of performing CL emission having a peak near 235 nm by excitation with an electron beam of this vapor phase magnesium oxide single crystal is as follows. Excitation is not performed from the magnesium oxide forming the thin-film magnesium oxide layer 4 in the example, and only CL emission having a peak at 300 to 400 nm is excited from this deposited magnesium oxide.

  As can be seen from FIGS. 5 and 6, CL emission having a peak in this wavelength range of 200 to 300 nm (particularly, around 235 nm within 230 to 250 nm) has a large particle size of the vapor-phase-processed magnesium oxide single crystal. The peak intensity increases.

  The vapor-phase-processed magnesium oxide single crystal has a characteristic of performing CL emission having a peak in this wavelength range of 200 to 300 nm, and has an energy level corresponding to the peak wavelength. The level can trap electrons for a long time (several milliseconds or more), so that these electrons are extracted by the electric field, so that the initial electrons necessary for the start of discharge can be obtained, and discharge characteristics such as discharge delay and discharge probability are obtained. It is speculated that this can be improved.

  The effect of improving the discharge characteristics by the vapor-phase method magnesium oxide single crystal increases as the peak intensity in the wavelength range of 200 to 300 nm at the time of CL emission increases. There is a correlation between the particle size.

  That is, when producing a vapor-phase-grown 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, the length of the flame in which magnesium and oxygen react Since the temperature difference between the flame and the surroundings becomes longer and the gas phase method magnesium oxide single crystal having a larger particle size corresponds to the peak wavelength in the wavelength range of 200 to 300 nm, for example, as described above. It is considered that many energy levels are formed.

  In addition, the cubic multicrystal structure vapor-phase-process magnesium oxide single crystal contains many crystal plane defects, and it is speculated that the existence of this plane defect energy level further contributes to the improvement of the discharge probability. Is done.

  FIG. 8 is a graph showing the correlation between the CL emission intensity characteristics of the vapor-phase-process magnesium oxide single crystal and the discharge delay.

  From FIG. 8, it can be seen that the gas phase process magnesium oxide single crystal has a CL emission characteristic with a peak wavelength of 235 nm, whereby the discharge delay in the PDP is shortened. It can be seen that the stronger the peak intensity is, the greater the effect of reducing the discharge delay.

  In the above, the CL emission having a peak in the wavelength region of 200 to 300 nm (particularly, in the range of 230 to 250 nm, around 235 nm) when the electron emitting material contained in the electron emitting material layer 5 is excited by the electron beam. The case where the material is a magnesium oxide crystal such as a vapor-phase method magnesium oxide single crystal has been described. Any other material can be used as long as it can emit electrons into the discharge space when a voltage is applied.

  For example, other electron emission materials include alkaline earth oxides, alkali oxides, rare earth oxides and mixed crystals thereof, composite oxides containing transition metals, nitrides, sulfides, hydroxides, Examples thereof include carbonates, sulfates, carbon materials having negative electron affinity, diamond, and the like.

  The PDP is formed on the back surface of the thin-film magnesium oxide layer 4 by using the light absorbing layer 2 and the bus electrode Y1a of the row electrode Y1 as an exposure mask in the step of forming the electron emission material layer 5 at the time of manufacture. If the photosensitive material containing the electron-emitting material thus formed is exposed from the front glass substrate 1 side to form a pattern, the electron-emitting material layer 5 is placed on the bus electrode Y1a and the light absorption layer 2 of the row electrode Y1. Therefore, the alignment process at the time of forming the electron emission material layer 5 is not necessary, and the image display characteristics of the PDP are improved due to variations in the formation position of the electron emission material layer 5. It is possible to prevent the occurrence of variations, which can improve the performance of the PDP and reduce the manufacturing cost by improving the yield in the manufacturing process. To become.

  9 and 10 show a second example of the embodiment of the PDP according to the present invention, FIG. 9 is a front view schematically showing the PDP in the second example, and FIG. 10 shows V2-V2 of FIG. It is sectional drawing in a line.

  In the following description, the same structural parts as those of the PDP of the first embodiment will be described with reference to FIGS. 9 and 10 with the same reference numerals as those in FIGS.

  9 and 10, a plurality of pairs of row electrodes (X2, Y2) are parallel to the back surface of the front glass substrate 1 serving as a display surface so as to extend in the row direction of the front glass substrate 1 (left and right direction in FIG. 1). Is arranged.

  The row electrode X2 is formed in a T shape by a bus electrode X2a made of a metal film extending in a strip shape in the row direction of the front glass substrate 1 and a transparent conductive film such as ITO, and the middle portion of the narrow leg portion is The wide end portion is connected to the equally spaced positions of the bus electrode X2a and includes a plurality of transparent electrodes X2b protruding to the row electrode Y1 side.

  Similarly, the row electrode Y2 is formed in a T-shape by a bus electrode Y2a made of a metal film extending in a strip shape in a direction parallel to the row electrode X2 and a transparent conductive film such as ITO, and between the narrow leg portions. The portion is connected to the equidistant position of the bus electrode Y2a, and the wide tip portion is constituted by a plurality of transparent electrodes Y2b protruding to the row electrode X1 side.

  The row electrodes X2 and Y2 are alternately arranged in the column direction (vertical direction in FIG. 9) of the front glass substrate 1, and the transparent electrodes X2b and Y2b arranged in parallel along the bus electrodes X2a and Y2a Extending to the paired row electrode side, the top sides of the wide portions of the transparent electrodes X2b and Y2b are opposed to each other via a discharge gap g2 having a required width.

  On the back surface of the front glass substrate 1, a black or dark light absorption layer (light shielding layer) 12 extending in a strip shape in the row direction is formed at an intermediate position between the row electrode pairs (X2, Y2) adjacent in the column direction. ing.

  A dielectric layer 3 is formed on the back surface of the front glass substrate 1. The dielectric layer 3 covers the row electrode pair (X 2, Y 2), the light absorption layer 12, and the back surface of the front glass substrate 1.

  A thin film magnesium oxide layer (hereinafter referred to as a thin film magnesium oxide layer) 4 formed by vapor deposition or sputtering is further formed on the back side of the dielectric layer 3, and the thin film magnesium oxide layer 4 forms a dielectric layer. The entire back surface of 3 is covered.

  Then, at the position facing the bus electrode Y2a of each row electrode Y2 on the back surface of the thin-film magnesium oxide layer 4, each of the row electrodes Y2a extends in a row shape by an electron emission material as will be described later and is substantially in the same column direction as the bus electrode Y2a. A band-shaped electron emission material layer 15 having a width of 1 mm is formed.

  On the other hand, on the display side surface of the rear glass substrate 6 arranged in parallel with the front glass substrate 1 at a predetermined interval, the column electrode D is paired with each other of each row electrode pair (X2, Y2). The electrodes are arranged in parallel at predetermined intervals so as to extend in a direction (column direction) orthogonal to the row electrode pair (X2, Y2) at a position facing the transparent electrodes X2b, Y2b.

  A white column electrode protective layer (dielectric layer) 7 covering the column electrode D is further formed on the display side surface of the rear glass substrate 6, and a partition wall 18 is formed on the column electrode protective layer 7. Has been.

  The partition wall 18 is formed in a substantially lattice shape by a horizontal wall 18A extending in the row direction at a position facing each light absorption layer 12 and a vertical wall 18B extending in the column direction at an intermediate position between adjacent column electrodes D. ing.

  Due to the substantially lattice-shaped partition walls 18, the discharge space between the front glass substrate 1 and the rear glass substrate 6 is formed in a portion facing the transparent electrodes X2b and Y2b that are paired with each other in each row electrode pair (X2, Y2). Each formed discharge cell C2 is divided into squares.

    A phosphor layer 9 is formed on the side walls 18A and 18B of the partition wall 18 facing the discharge cell C2 and on the surface of the column electrode protection layer 7 so as to cover all five surfaces. The color of the body layer 9 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 C2.

  A discharge gas containing xenon is enclosed in the discharge space S.

The electron emission material for forming the electron emission material layer 15 is, for example, in the wavelength range of 200 to 300 nm (in particular, in the range of 230 to 250 nm, 235 nm by being excited by an electron beam, as in the first embodiment. A magnesium oxide crystal having an average particle diameter of 2000 angstroms or more including a vapor-phase-process magnesium oxide single crystal having a characteristic of performing CL emission having a peak in the vicinity) is used.
When the PDP is driven, reset discharge, address discharge and sustain discharge for image formation are performed in the discharge cell C2.

  During the driving of the PDP, the electron emission material forming the electron emission material layer 15 emits secondary electrons into the discharge cell C2 due to the discharge generated in the discharge cell C2, and after the discharge is completed, the thin film oxidation material is formed. It has a characteristic of continuing to emit secondary electrons over a longer time than MgO that forms the magnesium layer 4.

  The secondary electrons emitted from the electron emission material layer 5 function as initial electrons of the next generated discharge, and improve the discharge delay of the PDP for the same reason as described in the first embodiment. .

  That is, in the PDP, the address discharge is generated between the column electrode D and the bus electrode Y2a that is separated from the discharge gap g2 of the row electrode Y2 as a cathode.

  Therefore, the electron emission material layer 15 is formed in the region where the address discharge is generated, and the emission of secondary electrons from the electron emission material layer 15 to the region where the address discharge is generated is performed during the address discharge period. Since it is continuously performed, for example, the discharge delay of each address discharge performed in the sub-field method is reduced, and the address discharge period is shortened.

  Therefore, even in a PDP having a large number of scanning lines such as full high-definition, it is possible to prevent the address discharge period from becoming longer than that of the conventional PDP. As a result, the driver cost can be reduced.

  Here, in order to increase the amount of secondary electrons emitted into the discharge cell C2, the electron emission material layer is formed on the entire surface of the thin-film magnesium oxide layer 4 to thereby emit electrons at the portion facing the discharge cell C2. It is conceivable to increase the amount of material.

  However, when the electron emission material is a white powder, if the electron emission material layer is formed on the entire surface facing the discharge cell C, visible light generated from the phosphor layer 9 due to the sustain discharge is emitted. Scattered by the white electron-emitting material in the material layer, the transmittance is lowered, thereby reducing the luminance of the image.

  In the PDP, since the electron emission material layer 15 is formed in a limited region facing the bus electrode Y2a of the row electrode Y2, the film of the electron emission material layer 15 does not cause a significant decrease in visible light transmittance. By increasing the thickness and increasing the amount of the electron-emitting material forming the electron-emitting material layer 15, sufficient initial electrons (secondary electrons) necessary for shortening the discharge delay are supplied to the discharge region of the address discharge. It will be possible.

  Further, the PDP is formed when the electron emission material layer 15 is formed at a position facing the metal bus electrode Y2a, and the electron emission material forming the electron emission material layer 15 is a white powder. In the visible light generated from the phosphor layer 9 during the sustain discharge, visible light directed to the bus electrode Y2a is reflected into the discharge cell C2 by the white electron emission material layer 15, and further fluorescent in the discharge cell C2. By being reflected by the body layer 9 or the like and emitted from the front glass substrate 1, the light emission characteristics of the panel can be improved and the luminance of the screen can be increased.

  Furthermore, in the PDP, since the electron emission material layer is not formed on the entire display area of the panel, the sustain discharge generated through the discharge gap g2 between the transparent electrodes X2b and Y2b is accelerated more than necessary. Thus, it is possible to avoid the influence on the sustain discharge characteristics such that the discharge load is concentrated and the voltage drop occurs.

  In the above embodiment, the electron emission material layer may be formed at the position facing the bus electrode X2a of the row electrode X2 in the same manner as the row electrode Y2 side, and formed on the row electrode X2 side. The size of the electron emission material layer is not necessarily the same as that of the electron emission material layer 15 on the row electrode Y2 side.

  FIG. 11 is a front view schematically showing a third example of the embodiment of the PDP according to the present invention.

  Since the PDP of the third embodiment is the same as the PDP of the first embodiment except for the configuration of the electron emission material layer, the same structural portion as that of the first embodiment is shown in FIG. The description will be made with the same reference numerals.

  In FIG. 11, the electron emission material layer 25 is formed in an island-like form for each discharge cell C1 at a position facing the connection portion between the bus electrode Y1a of the row electrode Y1 and each transparent electrode Y1b. Yes.

  Then, the electron emission material layer 25 (R) formed for the discharge cell C1 (R) having the red phosphor layer and the discharge cell C1 (G) having the green phosphor layer were formed. The size of each of the electron emission material layer 25 (G) and the electron emission material layer 25 (B) formed for the discharge cell C1 (B) in which the blue phosphor layer is formed is determined by the size of the phosphor layer. It is set corresponding to the characteristics of the red, green and blue fluorescent materials to be formed with respect to the discharge delay.

  That is, since the address discharge generated between the row electrode Y1 and the column electrode is performed by counter discharge with the phosphor layer interposed therebetween, it is the same for the discharge cells C1 (R), C1 (G), and C1 (B). When the electron emission material layer having a size is formed in an island shape, a phosphor layer is formed between the discharge cells C1 (R), C1 (G), and C1 (B) due to the discharge delay of the address discharge. Variations occur due to differences in the characteristics of red, green, and blue fluorescent materials (address discharge characteristics such as discharge start voltage).

  For this reason, in this PDP, as shown in the drawing, there is a blue phosphor layer whose discharge delay of address discharge is larger than the discharge cells C1 (R) and C1 (G) in which red and green phosphor layers are formed. The size of the electron emission material layer 25 (B) formed for the formed discharge cell C1 (B) is set to the size of the electron emission material layer 25 formed for the discharge cells C1 (R) and C1 (G). It is formed so as to be larger than the sizes of (R) and 25 (G).

  As a result, when an address discharge is generated, the discharge cell C1 (B) has a larger amount than the other discharge cells C1 (R) and C1 (G) from the electron emission material layer 25 (B). Secondary electrons are generated, and the discharge delay variation among the discharge cells C1 (R), C1 (G), and C1 (B) is eliminated.

  In the illustrated example, the thicknesses of the electron emission material layers 25 (R), 25 (G), and 25 (B) are the same, and the electron emission material layer 25 (B) is viewed from the front glass substrate side. The area of the electron emission material layer 25 (B) is made larger than the area of the other electron emission material layers 25 (R) and 25 (G), so that the size of the electron emission material layer 25 (B) The discharge is set to be larger than the sizes of 25 (R) and 25 (G), but each electron emission material layer has the same area as viewed from the front glass substrate side and has a blue phosphor layer. Electron emission material formed for discharge cells C1 (R) and C1 (G) having phosphor layers of other red and green in the thickness of the electron emission material layer formed for cell C1 (B) Each electron emission material layer should be formed so that it is larger than the layer thickness. Good.

  In the above example, the discharge cells C1 (R), C1 (G), and C1 (B) have different electron emission material layer areas. However, at least two discharge cells are used. The area of the electron emission material layer may be different.

  In the above-described embodiment, the electron emission material layer may be formed at the position facing the bus electrode X1a of the row electrode X1 similarly to the row electrode Y1 side, and the electrons formed on the row electrode X1 side may be formed. The size of the emission material layer is not necessarily the same as that of the electron emission material layer 15 on the row electrode Y1 side.

  Other effects in this embodiment are the same as those in the first and second embodiments described above.

  FIG. 12 is a front view schematically showing a fourth example of the embodiment of the PDP according to the present invention.

  Since the PDP of the fourth embodiment is the same as the PDP of the first embodiment except for the configuration of the electron emission material layer, the same structural portion as that of the first embodiment is shown in FIG. The description will be made with the same reference numerals.

  In FIG. 12, an electron emission material layer 35X extending in a strip shape along the bus electrode X1a is formed at a position facing the bus electrode X1a of the row electrode X1 on the back surface of the thin-film magnesium oxide layer, and is formed on the bus electrode Y1a of the row electrode Y1. An electron emission material layer 35Y extending in a strip shape along the bus electrode Y1a is formed at the facing position.

  In the PDP, when an address discharge is generated between the scan electrode row electrode Y1 and the column electrode, secondary electrons are emitted from the electron emission material layer 35Y into the discharge cell C1, and the discharge delay of this address discharge is caused. Is improved.

  In addition, the electron emission material layer 35X is formed at a position facing the bus electrode X1a of the row electrode X1, which is a common electrode, thereby preventing erroneous discharge from occurring on the common electrode (row electrode X1) side. And the drive margin can be expanded.

  In the above embodiment, an example is shown in which the electron emission material layers 35X and 35Y have the same size, but the electron emission material layers formed on the row electrode X1 side and the row electrode Y1 side are shown. The size is not necessarily the same as that of the electron emission material layer 15 on the row electrode Y1 side.

  Other effects in this embodiment are the same as those in the first and second embodiments described above.

  FIG. 13 is a front view schematically showing a fifth example of the embodiment of the PDP according to the present invention.

  Since the PDP of the fifth embodiment is the same as the PDP of the first embodiment except for the configuration of the electron emission material layer, the same structural portion as that of the first embodiment is shown in FIG. The description will be made with the same reference numerals.

  In FIG. 13, an electron emission material layer 45X extending in a strip shape along the bus electrode X1a is formed at a position facing the bus electrode X1a of the row electrode X1 on the back surface of the thin film magnesium oxide layer, and is formed on the bus electrode Y1a of the row electrode Y1. An electron emission material layer 45Y extending in a strip shape along the bus electrode Y1a is formed at the facing position.

  The size of the portion of the electron emission material layer 45X facing each discharge cell C1 is larger than the size of the portion of the electron emission material layer 45Y facing each discharge cell C1 (in the illustrated example, The emission material layer 45X is formed so as to have a larger width in the column direction).

  In the PDP, when an address discharge is generated between the row electrode Y1 as a scan electrode and the column electrode, secondary electrons are emitted from the electron emission material layer 45 into the discharge cell C1, and the discharge delay of this address discharge is caused. Is improved.

  Then, an electron emission material layer 45X having a larger size of a portion facing the discharge cell C1 than the electron emission material layer 45Y is formed at a position facing the bus electrode X1a of the row electrode X1 which is a common electrode. In addition, it is possible to prevent erroneous discharge from occurring on the common electrode (row electrode X1) side and to increase the drive margin.

Other effects in this embodiment are the same as those in the first and second embodiments described above.

In each of the above embodiments, the row electrodes X (sustain electrodes, common electrodes) and the row electrodes Y (scanning electrodes) are alternately arranged in the column direction such as XY, XY,. The present invention has been described with reference to an example of the PDP. However, in the present invention, the row electrode X and the row electrode Y are adjacent to each other between the row electrode pair (X, Y) XY, YX, X- The present invention can also be applied to PDPs that are arranged alternately such as Y, Y-X,.

  The PDP of each of the above embodiments includes a front substrate and a rear substrate that are opposed to each other through a discharge space, a row electrode pair and a column electrode that are disposed between the front substrate and the rear substrate and generate a discharge in the discharge space, A dielectric layer that covers the row electrode pair, a discharge cell is formed in the discharge space, and a region facing the row electrode that constitutes the row electrode pair on the side facing the discharge cell of the dielectric layer The PDP of the embodiment in which an electron-emitting material layer including an electron-emitting material that emits electrons into the discharge cell by discharge in the discharge cell is patterned at least on a region facing the row electrode on the cathode side when discharge occurs Is an embodiment of the superordinate concept.

  In the PDP of the embodiment constituting this superordinate concept, reset discharge, address discharge, and sustain discharge for image formation are performed in the discharge cell, and during this driving, the electron emission material contained in the electron emission material layer is discharged. Secondary electrons continue to be emitted into the discharge space for a long time by the discharge generated in the cell.

  The secondary electrons emitted from the electron-emitting material layer function as initial electrons for the next generated discharge, and shorten the discharge delay of the next discharge generated in the discharge space.

  Accordingly, for example, in a PDP having a large number of scanning lines on the screen such as full high vision, the discharge period of the address discharge performed between the cathode-side row electrode and the column electrode in order to select the discharge cell to emit light is reduced. It is prevented from becoming long, and it is not necessary to drive the scanning line by dividing it into upper and lower parts for shortening the discharge period, and it is possible to prevent the driver cost from increasing.

It is a front view which shows the 1st Example of embodiment of this invention. It is sectional drawing in the V1-V1 line | wire of FIG. 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 magnesium oxide single crystal powder, and the wavelength of CL light emission. It is a graph which shows the relationship between the particle size of magnesium oxide and the intensity | strength 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 front view which shows the 2nd Example of embodiment of this invention. It is sectional drawing in the V2-V2 line | wire of FIG. It is a front view which shows the 3rd Example of embodiment of this invention. It is a front view which shows the 4th Example of embodiment of this invention. It is a front view which shows the 5th Example of embodiment of this invention.

Explanation of symbols

1 ... Front glass substrate (substrate)
DESCRIPTION OF SYMBOLS 3 ... Dielectric layer 4 ... Thin film magnesium oxide layer 5, 15, 25 (R), 25 (G), 25 (B), 35X, 35Y, 45X, 45Y ... Electron emission material layer 6 ... Back glass substrate (substrate)
9 ... phosphor layer C1, C1 (R), C1 (G), C1 (B), C2
... Discharge cell (unit emission region)
D: Column electrode (discharge electrode)
S: Discharge space X1, Y1, X2, Y2
... Row electrodes (discharge electrodes)
X1a, Y1a, X2a, Y2a
... Bus electrodes X1b, Y1b, X2b, Y2b
... Transparent electrodes g1, g2 ... Discharge gap

Claims (12)

A pair of substrates opposed via the discharge space; a discharge electrode disposed between the pair of substrates for generating discharge in the discharge space; and a dielectric layer covering the discharge electrode; In the plasma display panel in which the unit light emitting region is formed,
Electrons are injected into the unit light emitting region by discharge by the discharge electrode on at least the region facing the discharge electrode which becomes the cathode side when a discharge occurs, among the regions facing the discharge electrode on the side facing the unit light emitting region of the dielectric layer. A plasma display panel, wherein an electron emission material layer including an electron emission material to be emitted is patterned. The discharge electrode is provided on one substrate side of the pair of substrates and extends in the row direction, and a plurality of row electrode pairs arranged in parallel in the column direction, and is provided on the other substrate side and extends in the column direction. And a plurality of column electrodes that are arranged side by side in the row direction and each form a unit light emitting region in a discharge space of a portion that intersects the pair of row electrodes,
The electron emission material layer forms a pattern in a region facing a portion away from the discharge gap in the column direction of at least one of the row electrodes constituting the row electrode pair and facing each other via the discharge gap. The plasma display panel according to claim 1. Each of the row electrodes constituting the row electrode pair includes a bus electrode extending in the row direction and a transparent electrode extending from the bus electrode to the other row electrode side and facing each other via a discharge gap. Have
The plasma display panel according to claim 2, wherein the electron emission material layer is patterned in a region facing a bus electrode of a row electrode.   The electron emission material layer includes a bus electrode of each row electrode that is positioned back to back in adjacent row electrode pairs, and a non-display region of the panel that faces a portion between the bus electrodes positioned back to back 4. The plasma display panel according to claim 3, wherein the plasma display panel is patterned.   The plasma display panel according to claim 1, wherein the electron emission material layer is independently formed in an island shape for each unit light emitting region. For each unit light emitting region, a phosphor layer is formed of red, green, or blue fluorescent material,
6. The plasma display according to claim 5, wherein the electron-emitting material layers independently formed in an island shape for each unit light-emitting region have different sizes in at least two unit light-emitting regions having different phosphor layer colors. panel.   The electron-emitting material layer is patterned in a region facing the respective bus electrodes of one and the other row electrodes constituting the row electrode pair, and one of the row electrodes that generates a discharge with the column electrode 4. The plasma display panel according to claim 3, wherein the size of the electron emission material layer facing the bus electrode of the other row electrode is larger than the size of the electron emission material layer facing the bus electrode.   4. The pattern according to claim 3, wherein the electron-emitting material layer is patterned only in a region facing a bus electrode of one row electrode that generates a discharge with a column electrode among the row electrodes constituting the row electrode pair. The plasma display panel as described.   The electron-emitting material contained in the electron-emitting material layer 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. 2. The plasma display panel according to 1.   The plasma display panel according to claim 9, wherein a particle diameter of the magnesium oxide crystal is 2000 angstroms or more.   The plasma display panel according to claim 9, wherein the magnesium oxide crystal is generated by vapor-phase oxidation of heated magnesium vapor.   The plasma display panel according to claim 1, wherein the electron emission material is a white powder.