JP4016764B2 - Plasma display panel - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a plasma display panel known as a display device.
[0002]
[Prior art]
In recent years, expectations for high-definition and large-screen televisions such as high-definition television are increasing, and various displays such as CRT, liquid crystal display (hereinafter referred to as LCD), and plasma display panel (hereinafter referred to as PDP). In this field, a display suitable for this is being developed.
[0003]
Conventionally, CRTs that are widely used as television displays are excellent in terms of resolution and image quality, but are not suitable for large screens of 40 inches or more in that the depth and weight increase with the size of the screen. It is. LCDs have excellent performance such as low power consumption and low driving voltage, but there are technical difficulties in producing a large screen, and the viewing angle is limited.
[0004]
On the other hand, the PDP can realize a large screen even with a small depth, and a product of the 60-inch class has already been developed.
[0005]
PDPs are roughly classified into a direct current type (DC type) and an alternating current type (AC type). At present, the AC type suitable for increasing the size is the mainstream.
[0006]
[Problems to be solved by the invention]
Such PDPs are required to have high definition in order to perform high-quality image display. For this purpose, technology for further improving the light emission efficiency to achieve high luminance and keeping the discharge voltage low is indispensable. It is.
[0007]
That is, in the current 40 to 42 inch class television PDP, in the case of NTSC pixel level (640 × 480 pixels, cell pitch 0.43 mm × 1.29 mm, 1 cell area 0.55 mm ² ). Panel efficiency and screen brightness of about 1.2 (lm / w) and 400 (cd / m ² ) have been obtained (for example, flat panel display 1997 Part5-1 P198). A full-spec 42-inch high-definition television that is desired to be commercialized has 1920 × 1125 pixels and a cell pitch of 0.15 mm × 0.48 mm. In this case, the area of one cell is 0.072 mm ^2. Therefore, it is 1/7 to 1/8 as compared with NTSC. Therefore, when a 42-inch high-definition television PDP is manufactured with a conventional cell configuration, the panel efficiency is 0.15 to 0.17 (lm / w) and the screen brightness is 50 to 60 (cd / w). m ² ) is expected to decrease.
[0008]
Therefore, in a 42-inch high-definition television PDP, if the brightness (500 cd / m ² ) of the current NTSC CRT is to be obtained, the efficiency is increased 10 times (5 (lm / w)) or more. (Flat panel display 1997 Part5-1 P200).
[0009]
The present invention has been made in view of the above problems. Even when the PDP has a high definition, the discharge cell pitch is narrow, and the size of the discharge cell is small, the crosstalk does not occur and the brightness is high. An object is to realize a PDP capable of displaying an image.
[0010]
[Means for Solving the Problems]
In order to achieve the above object, the plasma display panel of the present invention comprises a first display electrode comprising a first scan electrode and a first sustain electrode, a second scan electrode and a second sustain electrode. A plasma display panel in which a plurality of display electrodes formed on a front plate are formed by a second display electrode provided so as to sandwich the first display electrode between the electrode and the second sustain electrode, The discharge start voltage V ₂ determined by the inner distance d ₂ between the scan electrode and the second sustain electrode is lower than the discharge start voltage V ₁ determined by the inner distance d ₁ between the first scan electrode and the first sustain electrode. to a distance d ₁ of the inner and first scan electrode and the first sustain electrode, by constituting determine the distance d ₂ inside of the second scan electrode and the second sustain electrode, first second scan Between the electrode and the second sustaining electrode Conductive to generate, and performs a sustain discharge in the form of generating a discharge between the first scan electrode and the first sustain electrode subsequent to it.
[0012]
DETAILED DESCRIPTION OF THE INVENTION
That is, the invention according to claim 1 of the present invention includes a first display electrode including a first scan electrode and a first sustain electrode, a second scan electrode, and a second sustain electrode. And a second sustaining electrode, and a second display electrode provided so as to sandwich the first display electrode therebetween. The discharge start voltage V ₂ determined by the inner distance d ₂ between the electrode and the second sustain electrode is lower than the discharge start voltage V ₁ determined by the inner distance d ₁ between the first scan electrode and the first sustain electrode. , the distance d ₁ of the inner and first scan electrode and the first sustain electrode, by constituting determine the distance d ₂ inside of the second scan electrode and the second sustain electrode, first second scan electrode A discharge between the second sustain electrode and the second sustain electrode And performs a sustain discharge in the form of generating a discharge between the first scan electrode and the first sustain electrode subsequently.
[0014]
Further, the invention according to claim 2, in the invention described in claim 1, distance d ₁ of the inner and first scan electrode and the first sustain electrode spacing smaller than the minimum discharge start voltage in a Paschen curve That's it.
[0015]
The invention according to claim 3 is the invention according to claim 1 or 2 , wherein the charge / discharge time constant of the first display electrode is two orders of magnitude greater than the charge / discharge time constant of the second display electrode. is there.
[0016]
The invention according to claim 4 is the invention according to any one of claims 1 to 3, wherein the electrical resistance of the first display electrode is 1 kΩ / □.
[0017]
The invention according to claim 5 is the plasma display panel according to any one of claims 1 to 4 , wherein the gas pressure of the discharge gas sealed inside is 100 Torr or less.
[0018]
Hereinafter, an embodiment of the present invention will be described, but the embodiment of the present invention is not limited thereto.
[0019]
PDPs generate ultraviolet rays by gas discharge and excite phosphors with the ultraviolet rays to emit light and perform color display. Broadly speaking, there are AC and DC types in terms of driving, and surface discharge is the type of discharge. There are two types, a counter discharge type and a counter discharge type, but at present, the mainstream of the plasma display panel is a surface discharge type of a three-electrode structure because of high definition, large screen, and easy manufacturing. The structure has a pair of display electrodes adjacent in parallel on one substrate, an address electrode arranged in a direction intersecting the display electrode on the other substrate, a partition, and a phosphor layer. The phosphor layer can be made relatively thick and is suitable for color display using a phosphor.
[0020]
Such a PDP is capable of high-speed display compared to a liquid crystal panel, has a wide viewing angle, is easy to increase in size, and is self-luminous, so that the display quality is high. Recently, it has attracted particular attention among panel displays, and is used for various purposes as a display device at a place where many people gather or a display device for enjoying a large screen image at home.
[0021]
Here, the structure of a PDP according to an embodiment of the present invention is shown in FIGS. FIG. 1 is a cross-sectional perspective view showing a schematic configuration of a PDP according to an embodiment of the present invention, and FIG. 2 is a cross-sectional view showing a configuration of display electrodes of the PDP according to an embodiment of the present invention.
[0022]
The PDP is composed of a front plate 1 and a back plate 2. The front plate 1 includes a plurality of display electrodes 4 formed on a transparent and insulating substrate 3 such as a glass substrate made of sodium borosilicate glass by a float method, and a dielectric formed so as to cover the display electrodes 4. The body layer 5 and the protective film 6 made of MgO formed on the dielectric layer 5 are configured. The display electrode 4 includes a first display electrode 7 composed of transparent electrodes 7a and 7b formed of a transparent and conductive material such as ITO, and a first display electrode 7 composed of the transparent electrodes 7a and 7b. In the middle, that is, a second electrode comprising bus electrodes 8a and 8b made of, for example, Ag provided in contact with the first display electrode so as to sandwich the first display electrode between the first display electrode 7 and the first display electrode 7. The display electrode 8 is constituted. That is, the transparent electrodes 7a and 7b operate as the first scanning electrode 7a and the first sustaining electrode 7b to form the first display electrode 7, and the bus electrodes 8a and 8b serve as the second scanning electrode 8a and the second sustaining electrode 8b. The second display electrode 8 is configured by operating.
[0023]
Here, in the present embodiment, the discharge start voltage V between the two electrodes schematically shown in FIG. 3 is related to p × d, which is the product of the distance between the two electrodes d and the gas pressure p therebetween. In the so-called Paschen curve, the discharge start voltage V ₂ between the second scan electrode 8a and the second sustain electrode 8b is the discharge start voltage V between the first scan electrode 7a and the first sustain electrode 7b. to be lower than _1, the distance d ₁ between the first scan electrode 7a and the first sustain electrode 7b, are constructed by determining the distance d ₂ between the second scan electrode 8a and the second sustain electrode 8b .
[0024]
The back plate 2 has an address electrode 10 formed in a direction orthogonal to the display electrode 4 on a substrate 9 disposed opposite to the substrate 3, and a dielectric layer 11 formed so as to cover the address electrode 10. And a plurality of barrier ribs 12 formed in a stripe shape in parallel with the address electrodes 10 on the dielectric layer 11 between the address electrodes 10, and a phosphor layer 13 formed between the barrier ribs 12. For color display, the phosphor layer 13 is usually arranged in order of three colors of red, green, and blue.
[0025]
The PDP has a surrounding sealing member (not shown) in a state in which the front plate 1 and the back plate 2 described above are arranged to face each other with a minute discharge space so that the display electrodes 4 and the address electrodes 10 are orthogonal to each other. The discharge space is filled with, for example, Ne-Xe 5% discharge gas.
[0026]
The discharge space of the PDP is partitioned into a plurality of sections by the barrier ribs 12, and display electrodes 4 are provided so that a plurality of discharge cells serving as unit light emitting regions are formed between the barrier ribs 12. The address electrodes 10 are arranged orthogonally. Then, a discharge is generated by a periodic voltage applied to the address electrode 10 and the display electrode 4, and an ultraviolet ray resulting from this discharge is irradiated to the phosphor layer 13 to convert it into visible light, thereby displaying an image.
[0027]
In the above configuration, as described above, the discharge start voltage V ₂ between the second scan electrode 8a and the second sustain electrode 8b is, discharge starts between the first scan electrode 7a and the first sustain electrode 7b as is lower than the voltage V _1, the distance d ₁ between the first scan electrode 7a and the first sustain electrode 7b, and the distance d ₂ between the second scan electrode 8a and the second sustain electrode 8b is formed is determined Therefore, when a sustain pulse voltage V _c having a relationship of V ₁ > V _c ≧ V ₂ is applied to the first display electrode 7 and the second display electrode 8 during the sustain discharge, first, the second display is performed. Discharge occurs between the second scan electrode 8a, which is the electrode 8, and the second sustain electrode 8b. Here, normally, since V ₁ > V _c , no discharge occurs in the first display electrode 7, but in the case of the present embodiment, charging is caused by the discharge of the second display electrode 8. Particles, excited particles, and the like are generated, and the discharge starting voltage between the first scan electrode 7a and the first sustain electrode 7b is lowered by a so-called priming effect. Discharge occurs also in one display electrode 7. In other words, in this case, the distance d ₁ between the first scan electrode 7a and the first sustain electrode 7b constituting the first display electrode 7 is discharged due to the priming effect even if the sustain pulse voltage is V _c. It is necessary that the discharge start voltage V ₁ (> V _c ) is sufficient to be generated.
[0028]
The sustain discharge as described above extends and spreads from the second display electrode 8 to the first display electrode 7, that is, from the outside to the inside, in the discharge cell. Since the sustain discharge is in such a discharge form, the occurrence of crosstalk between adjacent discharge cells can be suppressed, and the luminance can be improved by expanding the discharge region. Even when the cell pitch is narrow and the size of the discharge cell is small, it is possible to perform good image display with no crosstalk and high luminance.
[0029]
Here, in the above description, the sustain pulse voltage V _c having a relationship of V ₁ > V _c ≧ V ₂ is applied as the sustain pulse voltage V _c applied to the first display electrode 7 and the second display electrode 8 during the sustain discharge. _Although an example in which _c is shown is shown, even when the sustain pulse voltage V _c having a relationship of V _c ≧ V ₁ > V ₂ is applied, the discharge is generated in the descending order of the discharge start voltage. A sustain discharge of the form is obtained. At this time, the discharge in the first display electrode 7 generated following the discharge in the second display electrode 8 is generated by the sustain pulse voltage V _c regardless of the priming effect.
[0030]
Further, in the above embodiment, the distance d ₁ between the first scan electrode 7a and the first sustain electrode 7b, and the distance d ₂ between the second scan electrode 8a and the second sustain electrode 8b is always d _Since the relationship ₁ ≦ d ₂ is satisfied, the discharge start voltage V ₂ between the second scan electrode 8a and the second sustain electrode 8b becomes the discharge start between the first scan electrode 7a and the first sustain electrode 7b. In order to determine and configure d ₁ and d ₂ so as to be lower than the voltage V ₁ , in the Paschen curve schematically shown in FIG. 3, d ₁ is an interval d at which the minimum discharge start voltage V _min is obtained. ^* It is necessary to be smaller.
[0031]
Further, it is desirable that the discharge spread in the first display electrode 7 does not occur abruptly in a short time, but is gentle and long-term. For this purpose, the electrical resistance R of the first display electrode 7 and the capacitor It is preferable to limit the current flowing during discharge by reducing the charge / discharge time constant defined by R × C, which is the product of the capacity C. For this purpose, it is preferable that the charge / discharge time constant of the first display electrode 7 be two digits or more larger than the charge / discharge time constant of the second display electrode 8. This can be realized by increasing the electric resistance value R. For example, it has been confirmed that a desirable discharge state can be obtained by setting 1 kΩ / □. An example of a material for forming the first display electrode 7 having such an electric resistance value is ITO.
[0032]
In addition, since the discharge at the second display electrode 8 triggers the sustain discharge of the PDP according to the present embodiment, the electrical resistance of the second display electrode 8 is as small as possible and It is preferable that the electron supply be performed sufficiently and quickly. In this case, the first display electrode 7 and the second display electrode 7 are connected to the first display electrode 7 for the purpose of preventing the inflow of electrons from the second display electrode 8 to the first display electrode 7 from the viewpoint of slow and long-term discharge. It is preferable to contact the display electrode 8 through a resistance layer.
[0033]
Moreover, in the above description, the example which provided the 1st display electrode 7 and the 2nd display electrode 8 in the display electrode 4 in contact was shown, However, it does not restrict in particular, As shown in FIG. Even in the configuration in which the first display electrode 7 and the second display electrode 8 are separated from each other without being brought into contact with each other, the sustain discharge has the same form as described above, and the same effect can be obtained. In the configuration shown in FIG. 4, the same form as the sustain discharge in the PDP according to the present embodiment can be achieved by applying separate sustain pulses to the first display electrode 7 and the second display electrode 8, respectively. For this purpose, there is a problem that the driving device of the PDP becomes complicated. However, according to the present embodiment, the same driving device as the conventional one can be used, and the above-described effects can be obtained.
[0034]
Also, PDP to the PDP configured as described above, which conversely is determined from PDP pixel specification, the minimum discharge start voltage between the second scan electrode 8a and the second sustain electrode 8b interval is d ₂ The internal pressure is 100 Torr or less from the Paschen curve. That is, with the configuration of the PDP described above, the applied pulse voltage for the sustain discharge can be minimized by further reducing the gas pressure of the discharge gas sealed inside to 100 Torr or less, thereby further improving the efficiency. Can do.
[0035]
Further, the distance d ₂ between the second scan electrode 8a and the second sustain electrode 8b is determined so that the discharge start voltage becomes the minimum value in the Paschen curve with respect to the pressure of the discharge gas sealed in the PDP. Although it is preferable, the shape of the Paschen curve is determined so that it is shifted to the right side even if it is slightly deviated from this minimum value because the change rate is smaller and stable on the right side than the left side. It is preferable.
[0036]
【The invention's effect】
As described above, according to the present invention, even when the PDP has a high definition, the discharge cell pitch is narrow, and the size of the discharge cell is small, there is no crosstalk and high brightness, and a PDP capable of displaying a good image. Can be realized.
[Brief description of the drawings]
1 is a cross-sectional perspective view illustrating a schematic configuration of a plasma display panel according to an embodiment of the present invention. FIG. 2 is a cross-sectional view illustrating a configuration of display electrodes of the plasma display panel according to an embodiment of the present invention. FIG. 4 is a schematic diagram showing a Paschen curve. FIG. 4 is a cross-sectional view showing another configuration of display electrodes of a plasma display panel according to an embodiment of the present invention.
DESCRIPTION OF SYMBOLS 1 Front plate 2 Back plate 3 Substrate 4 Display electrode 5 Dielectric layer 6 Protective film 7 First display electrode 7a First scan electrode 7b First sustain electrode 8 Second display electrode 8a Second scan electrode 8b Second sustain electrode 13 Fluorescence Body layer

Claims (5)

A first display electrode comprising a first scan electrode and a first sustain electrode, a second scan electrode and a second sustain electrode, the first display electrode being interposed between the second scan electrode and the second sustain electrode; the second display electrode and the configured display electrodes provided to sandwich a plasma display panel in which a plurality formed in the front plate, in Paschen curve, at intervals d ₂ of the inner and the second scan electrode and the second sustain electrode determined discharge starting voltage V ₂ is to be lower than the discharge start voltages V ₁ determined by the distance d ₁ of the inner and first scan electrode and the first sustain electrode, the inner and first scan electrode and the first sustain electrode First, a discharge is generated between the second scan electrode and the second sustain electrode by determining and configuring the interval d ₁ and the inner distance d ₂ between the second scan electrode and the second sustain electrode. Subsequently, the first scan electrode and the first sustain electrode In a plasma display panel for sustain discharge in the form of a discharge is generated. 2. The plasma display panel according to claim 1 , wherein an interval d ₁ inside the first scan electrode and the first sustain electrode is smaller than an interval at which the minimum discharge start voltage in the Paschen curve is obtained. The plasma display panel according to claim 1 or 2 , wherein the charge / discharge time constant of the first display electrode is two digits or more larger than the charge / discharge time constant of the second display electrode.   The plasma display panel according to any one of claims 1 to 3, wherein the electric resistance of the first display electrode is 1 kΩ / □. The plasma display panel according to any one of claims 1 to 4 , wherein a gas pressure of a discharge gas sealed inside is 100 Torr or less.

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