JP2001013916A - Method and device for driving plasma display panel - Google Patents

Abstract

PROBLEM TO BE SOLVED: To lengthen the life of a panel by preventing the deterioration of a protective film only on one side main electrode due to an ion impact at an address time related to a PDP covering a pair of main electrodes with the protective film. SOLUTION: When a plasma display panel consisting of a pair of substrates wherein a discharge cell is arranged in matrix between the substrates and consisting of a structure that first and second main electrodes generating a main discharge for turning a discharging cell on are arranged alternately and in parallel on one side substrate and the protective film is formed on it, and address electrodes generating an address discharge for selecting the discharge cell to be turned on are arranged in parallel in the direction crossing the main electrodes on the other side substrate is driven, when the discharge cell to be turned on is to be selected, the address discharge between the address electrode and the first main electrode and the address discharge between the address electrode and the second main electrode are generated alternately at every prescribed period.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a plasma display panel (PDP), and more particularly, to a plasma display panel (PDP) in which a pair of main electrodes are arranged in respective discharge cells arranged in a matrix, and the main electrodes are covered with a protective film. Regarding the covered PDP.

[0002]

2. Description of the Related Art A PDP is a thin display device which has excellent visibility, can perform high-speed display, and has a relatively large screen. Among others, the surface discharge type PDP of the matrix display type is a PDP in which display electrodes to be paired at the time of applying a driving voltage are arranged on the same substrate, and is suitable for color display using a phosphor.

Conventionally, for example, a three-electrode surface discharge type color PDP of an AC drive system has the following configuration.

FIG. 7 is a configuration diagram of a conventional plasma display device. The plasma display device 100 is for selectively lighting the AC-driven three-electrode surface discharge type PDP 20 which is a matrix type color display device and the cells C arranged in a matrix constituting a screen (screen) SC. The drive unit 80 is used as a wall-mounted television receiver, a monitor of a computer system, and the like.

The PDP 20 is referred to as a pair of first and second surface discharges (display discharges because they are main discharges for display, and sustain discharges because they are lighting sustain discharges. Hereinafter, sustain discharges). The main electrode for generating (called a display electrode because it is an electrode for display discharge)
It is called a sustain electrode because it is an electrode for sustain discharge. This is a PDP having a three-electrode surface discharge structure in which X and Y (hereinafter, referred to as sustain electrodes) are arranged in parallel, and in each cell C, the sustain electrodes X and Y intersect with an address electrode A as a third electrode. The sustain electrodes X and Y extend in the row direction (horizontal direction) of the screen, and one sustain electrode Y is used as a scan electrode for selecting a cell C in a row unit at the time of addressing. The address electrode A extends in the column direction (vertical direction) and is used as a data electrode for selecting a cell C in a column unit.
The area where the sustain electrode group and the address electrode group intersect is the display area, that is, the screen SC.

The drive unit 80 includes a controller 81,
It has a frame memory 82, a data processing circuit 83, a subfield memory 84, a power supply circuit 85, an X driver 87, a Y driver 88, and an address driver 89.
A frame (expressed as a field) in pixel units indicating the luminance level (gradation level) of each of G (green), B (blue), and R (red) from an external device such as a TV tuner or a computer is provided to the drive unit 80. Data Df is input together with various synchronization signals.

[0007] The field data Df is once stored in a frame memory 82 and then sent to a data processing circuit 83. The data processing circuit 83 is a data conversion unit that divides one field into a predetermined number of subfields for performing gradation display, and sets a combination of the subfields to be lit among the subfields. The field data Dsf is output. The subfield data Dsf is stored in the subfield memory 84. The value of each bit of the subfield data Dsf is information indicating the necessity of lighting of the cell in the subfield, more specifically, information indicating the necessity of the address discharge.

The X driver 87 applies a drive voltage to the sustain electrode X, and the Y driver 88 applies a drive voltage to the sustain electrode Y. The address driver 89 applies a drive voltage to the address electrode A according to the subfield data Dsf. These drivers are supplied with predetermined power from a power supply circuit 85.

When displaying the screen SC, first, the sustain electrode Y is used as a scanning electrode to select (address) a cell C to be lit. At this time, a voltage is sequentially applied to the sustain electrode Y, and a voltage is applied to the address electrode A corresponding to the cell C to be lit, so that an address discharge is generated between the address electrode A and the sustain electrode Y.

Next, the sustain discharge is continued between the sustain electrode X and the sustain electrode Y of the selected cell C by the number of times corresponding to the desired luminance and color by utilizing the residual charge at the time of the address discharge.

A dielectric layer is formed on the sustain electrodes X and Y. To prevent the dielectric layer from being deteriorated by the discharge,
Usually, a protective film made of MgO is formed on the dielectric layer on the sustain electrodes X and Y.

As described above, in the driving of the conventional AC type PDP, an address discharge is generated between one of the sustain electrodes X and Y and the address electrode A, and thereafter, between the sustain electrodes X and Y. The screen is displayed by continuing the sustain discharge the number of times corresponding to the brightness and the color.

That is, the sustain electrode used in the address discharge is always a Y electrode, and its potential is lower than that of the address electrode A. Therefore, during the address discharge, a large amount of ions are deposited on the protective film on the sustain electrode Y. Shock was being given.

[0014]

The ion bombardment of the protective film on the sustain electrode Y during the address discharge is as follows.
The sustain electrode X, which is considerably large and has been driven for a long time,
It has been found that the deterioration of the protective film on each Y electrode is more remarkable on the Y electrode. When the deterioration of the protective film on the sustain electrode Y progresses, the voltage of the address discharge increases, causing a reduction in panel life.

The present invention has been made in view of such circumstances, and has been developed in consideration of an AC drive type three-electrode surface discharge type PDP.
The present invention provides a method and apparatus for driving a plasma display panel, which prevents deterioration of a protective film on a sustain electrode Y due to ion bombardment at the time of addressing, thereby extending the life of the panel.

[0016]

SUMMARY OF THE INVENTION The present invention comprises a pair of substrates in which discharge cells are arranged in a matrix between the substrates, and one of the first substrates generates a main discharge for lighting the discharge cells. And a second main electrode are alternately arranged in parallel, on which a protective film is formed, and on the other substrate, an address electrode for generating an address discharge for selecting a discharge cell to be lit is provided with the main electrode. In driving a plasma display panel having a structure arranged in parallel to the intersecting direction, when selecting a discharge cell to be lit, an address discharge between an address electrode and a first main electrode, an address discharge between an address electrode and a second A method for driving a plasma display panel, characterized in that an address discharge with a main electrode is alternately generated every predetermined period.

That is, in the present invention, the address discharge is performed not only between the address electrode and the first main electrode but also between the address electrode and the second main electrode, so that the first and second electrodes are discharged. Dispersion of the deterioration of the protective film is extended to extend the life of the panel.

[0018]

BEST MODE FOR CARRYING OUT THE INVENTION As a PDP to which the driving method of the present invention can be applied, any well-known three-electrode surface discharge type PDP of an AC driving system generally used in the field can be applied.

In the present invention, when a discharge cell to be lit is selected, a voltage is sequentially applied by using one of the first and second main electrodes as a scanning electrode, and during this time, the lighting is performed. It means that an address discharge is generated by applying a voltage to an address electrode corresponding to a discharge cell to be addressed.

In the present invention, the generation of the address discharge alternately every predetermined period means that the protective film on the first main electrode and the protective film on the second main electrode are almost uniformly deteriorated. This means that an address discharge is generated by alternately using the first main electrode and the second main electrode. In this sense, every predetermined period may be any period. For example, one address may be used, or several addresses may be used. Further, any time, such as every 10 minutes, every hour, every day, every month, every year, etc., may be adopted with a time limit. When a time limit is imposed, a clock of a built-in CPU may be used, or an external clock may be added.

According to another aspect, the present invention comprises a pair of substrates in which discharge cells are arranged in a matrix between the substrates, and one of the substrates generates a main discharge for lighting the discharge cells. The first and second main electrodes are alternately arranged in parallel, a protective film is formed thereon, and the other substrate has an address electrode for generating an address discharge for selecting a discharge cell to be turned on. For driving a plasma display panel having a structure arranged in parallel with a direction intersecting with the address electrodes, wherein an address discharge is generated between an address electrode and a first main electrode when a discharge cell to be lit is selected. A first address discharge generator, a second address discharge generator for generating an address discharge between an address electrode and a second main electrode when a discharge cell to be lit is selected, and a first address discharge generator An address discharge with the address discharge by the second address discharge generator, an apparatus for driving a plasma display panel comprising a control unit that alternately switches for each predetermined time period.

Hereinafter, the present invention will be described in detail based on an embodiment shown in the drawings. Note that the present invention is not limited to this.

FIG. 1 shows a PD to which the driving method of the present invention is applied.
It is a perspective view showing composition of P. In the figure, 10 is AC
It is a three-electrode surface discharge type PDP of a driving system. PDP10
Are the front substrate 11 and the rear substrate 2 made of glass.
And 1.

On the inner surface of the front-side substrate 11, sustain electrodes X and Y for generating surface discharge are arranged substantially parallel to the horizontal direction for each display line L, on which a dielectric layer 17 and MgO are formed. Is formed. Since the sustain electrodes X and Y are provided on the front substrate,
A transparent electrode 12 made of TO and a metal electrode (bus electrode) 13 made of Cr / Cu / Cr are formed.

On the inner surface of the rear substrate 21, a plurality of addresses (data) for generating an address discharge
An electrode A and a dielectric layer 24 are sequentially formed, and a large number of stripe-shaped barrier ribs (ribs) 29 for physically dividing a discharge so as to sandwich the address electrode A thereon are vertically formed (intersecting with the sustain electrode). (In the direction in which the phosphor layers 28R, 2R) extend in the elongated groove between the partition walls.
8G and 28B are formed. The arrangement pattern of the three colors is a stripe pattern in which the light emission colors of the cells in one column are the same and the light emission colors of adjacent columns are different.

The discharge space 30 is filled with a discharge gas in which xenon is mixed with neon as a main component (filling pressure is about 500 Torr), and the phosphor layers 28R, 28G, and 28B are locally irradiated by ultraviolet rays emitted by xenon during discharge. And emits light.

FIG. 2 is a circuit block diagram showing a configuration of a driving unit used in the driving method of the present invention. In this figure, 1 is a Y-side scanning driver for sequentially applying a scanning voltage to the sustain electrode Y, 2 is a Y-side common driver for simultaneously applying a sustain voltage to all the sustain electrodes Y during sustain discharge, 3 is a sustain electrode X
A scanning driver on the X side for sequentially applying a scanning voltage to
4 is an X-side common driver for simultaneously applying a sustain voltage to all the sustain electrodes X at the time of sustain discharge, 5 is an A-side driver for applying an address voltage to the address electrode A, and 6 is a Y-side common driver 2. , A control circuit for controlling the X-side common driver 4 and the A-side driver 5.

In this driving method, the voltage application of the A-side driver 5 is performed by the address driver 8 shown in FIG.
This is the same as the voltage application of No. 9.

The difference from the drive unit 80 shown in FIG. 7 is that, in the drive unit of FIG. 7, an address discharge when a discharge cell to be lit is selected is generated only between the address electrode A and the sustain electrode Y. However, in the present driving method, the sustain electrode is replaced at regular intervals.

That is, for a certain period, driving is performed such that an address discharge is generated between the address electrode A and the sustain electrode Y and a sustain discharge is generated between the sustain electrodes X and Y so that the lighting is maintained.

Then, for the next fixed period, an address discharge is generated between the address electrode A and the sustain electrode X, a sustain discharge is generated between the sustain electrodes X and Y, and the driving is performed so that the lighting is maintained. .

FIG. 3 is an explanatory diagram showing an outline of the gradation driving method. The gradation display (color reproduction) based on the number of sustain discharges is the same as that of the PDP 20 shown in FIG.

That is, the period Tf of one frame is divided into, for example, eight sub-frames SF, and the relative ratio of luminance of these sub-frames SF is 1: 2: 4: 8: 16: 32:
Weighting is performed so as to be 64: 128, and the number of sustain discharges in each subframe SF is set. As a result, 256 levels of luminance settings are performed for each of the RGB colors,
256 Displays ^three types of colors. Thus, the sub-frame SF in which the light emission time is controlled during the period Tf of one frame
Is obtained by inserting a plurality of.

Then, the period Tsf of each subframe
In (j), a reset period Tr in which the charges of all cells are set to "0", an address scan period Ta-sf in which an address discharge is generated to select a lighting cell, and a sustain discharge is generated to maintain lighting. Light emitting period (sustain period) T
s-sf (j).

In the above description, the reset period Tr
In the above description, the charges of all the cells are set to “0”. However, this is the case of driving a so-called write address type PDP in which charges are formed only in cells to be turned on during the address scanning period Ta-sf. Erasing the charge of the cells not lit during the address scanning period Ta-sf;
When driving a so-called erase address type PDP, charges are uniformly formed in all cells in the reset period Tr.

FIG. 4 is an explanatory diagram showing driving waveforms of the driving method according to the present invention. As shown in this figure, in this driving method, the PDP is driven as follows. That is, for a certain period, the driving as shown in FIG.
In the next fixed period, the driving as shown in FIG.

First, as shown in (a), in the reset period, a discharge is generated between all the sustain electrodes X and the sustain electrodes Y, and the wall charges of all the cells are set to "0". During this time, a constant voltage is applied to the address electrode A so that no discharge occurs between the sustain electrode X and the address electrode A.

Next, in the address scanning period, the sustain electrodes Y1 and
A scanning voltage (selection pulse) is sequentially applied to the sustain electrode Y, such as Y2,..., Yn, and a voltage (address pulse) is applied to a desired address electrode A during that time. By generating an address discharge with the electrode Y, a discharge cell to be lit is selected. During this time, the address electrode A and the sustain electrode X
A constant voltage is applied to the sustain electrode X so that no discharge occurs between the electrodes.

Next, in the sustain period, the sustain electrodes Y, Y are used by utilizing the residual wall charges formed at the time of addressing.
Sustain discharges are generated (the discharge cells are turned on) for the number of times corresponding to the luminance and hue between X. In other words, one pixel is constituted by three discharge cells of RGB, and a desired color can be reproduced by determining how many times the discharge cells of RGB are turned on. Only generate sustain discharge.

After the screen display by such driving is performed for a certain period of time, next, as shown in (b), a discharge is generated between all the sustain electrodes Y and the sustain electrodes X in the reset period. , The wall charges of all cells are set to “0”. During this time, a constant voltage is applied to the address electrode A so that no discharge occurs between the sustain electrode Y and the address electrode A.

Next, in the address scanning period, the sustain electrodes X1 and
A scanning voltage (selection pulse) is sequentially applied to the sustain electrode X, such as X2,..., Xn, and a voltage (address pulse) is applied to a desired address electrode A in the meantime. By generating an address discharge with the electrode X, a discharge cell to be lit is selected. During this time, the address electrode A and the sustain electrode Y
A constant voltage is applied to the sustain electrode Y so that a discharge does not occur between the sustain electrode Y.

Next, during the sustain period, the residual wall charges formed at the time of addressing are used to apply the voltage between the sustain electrodes Y and X in the same manner as when the address discharge is generated between the address electrode A and the sustain electrode Y. Generates a sustain discharge by the number of times corresponding to the luminance and the hue. At this time, there is no problem even if the direction of the voltage applied first is the same as that when the address discharge is generated between the address electrode A and the sustain electrode Y. That is, when an address discharge is generated between the address electrode A and the sustain electrode X, wall charges are formed on the X electrode. Thus, the first sustain discharge does not occur, but the second and subsequent sustain discharges occur, so there is no problem with the sustain discharge.

[0043]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Using the driving method of the present invention described above, a PD
An example in which P10 is driven will be described.

[Preparation of Panel 1] On the front substrate 11 made of soda lime glass, I
A transparent electrode 12 made of TO was formed. Next, a bus electrode 13 of Cr / Cu / Cr having a thickness of about 3.0 μm was formed on the transparent electrode 12 by sputtering.

Next, the bus electrode 13 and the transparent electrode 12
A dielectric layer 17 having a thickness of about 50 μm was formed by a screen printing method so as to cover. Further, a protective film 18 of MgO of about 6000 ° was formed on the dielectric layer 17 by a vapor deposition method, whereby the front substrate 11 was obtained.

After a base layer was formed on the back substrate 21 made of soda lime glass, an address electrode A made of Cr / Cu / Cr and having a thickness of about 2.0 μm was formed by sputtering. Next, a dielectric layer 24 having a thickness of about 20 μm was formed by a screen printing method so as to cover the address electrodes A. Thereafter, the partition walls 29 and the phosphor layers 28R, 28G, and 28B were formed by a known method, thereby obtaining the rear substrate 21.

The front substrate 11 thus obtained
The substrate and the rear substrate 21 were bonded together at an interval of about 200 μm and sealed, and a discharge gas was filled in a discharge space between the substrates to produce an AC-driven three-electrode surface discharge type PDP. Sustain electrodes are placed from above the screen in Y, X,
Y, X,..., And Y and X were even numbers.

[Preparation of Panel 2] A panel 2 was prepared in the same manner as the panel 1 except for the structure of the sustain electrode. The sustain electrodes X and Y have a so-called ALis structure as shown in FIG. That is, a PDP having a structure in which the sustain electrodes X and the sustain electrodes Y are arranged at equal intervals and one screen is displayed in odd and even fields is manufactured. Sustain electrodes are arranged from above the screen in X, Y, X,
An odd number of Y, X,..., Y, X was used.

Example 1 The panel 1 was driven for a long time in the driving sequence of the present invention. That is, the discharge electrode at the address was changed from the sustain electrode Y to the sustain electrode X and from the sustain electrode X to the sustain electrode Y at regular intervals. The proportions were 50% and 50%.

Here, at the time when the address selection was switched from the address electrode A-sustain electrode Y to the address electrode A-sustain electrode X, the scanning direction of the line was reversed. This is because there is a great correlation between the charging of the wall charges by the address and the scanning direction during the sustain discharge.

The discharge characteristics between the address electrode A and the sustain electrode Y were measured at regular intervals for the purpose of investigating the state of deterioration.

[Embodiment 2] The panel 2 was driven for a long time by the driving sequence of the present invention. That is, the discharge electrode at the address was changed from the sustain electrode Y to the sustain electrode X and from the sustain electrode X to the sustain electrode Y at regular intervals. The proportions were 50% and 50%.

[0053] Here, when the address selection in the address electrodes A- sustain electrode Y, a second line address from the sustain electrode Y ₁ of starts, between sustain electrodes Y _n and sustain electrodes X _n, and sustain electrodes Y _A sustain discharge is generated between _n and the sustain electrode _{Xn + 1} .

[0054] When switched to the address selection in the address electrodes A- sustain electrodes X is first line starts the address from sustain electrode X _1, between the sustain electrode X _n and sustain electrode Y _n-1, and a sustain electrode the sustain discharge is generated between the X _n and sustain electrode Y _n. The scanning direction of the line was the same before and after switching.

The discharge characteristics between the address electrode A and the sustain electrode Y were measured at regular intervals for the purpose of investigating the state of deterioration.

[Embodiment 3] The panel 1 was driven for a long time in a conventional driving sequence. However, the address discharge was performed only between the address electrode A and the sustain electrode Y, and the potential of the address electrode A and the sustain electrode Y at the time of addressing was reversed from the driving method of the PDP 20 shown in FIG. That is, with respect to the potentials of the address electrode A and the sustain electrode Y at the time of addressing, the potential of the address electrode A was set lower than the potential of the sustain electrode Y.

The discharge characteristics between the address electrode A and the sustain electrode Y were measured at regular intervals for the purpose of investigating the state of deterioration.

COMPARATIVE EXAMPLE The panel 1 was driven for a long time in the driving sequence of the PDP 20 shown in FIG.
Then, similarly to Examples 1 to 3, the discharge characteristics between the address electrode A and the sustain electrode Y were measured at regular intervals for the purpose of investigating the state of deterioration.

FIG. 6 is a graph showing the relationship between the drive time and the address discharge voltage. As shown in this graph, in the comparative example, the time required for the address discharge voltage to reach 5 V was about 1000 hours, whereas in Example 1, the time required for the address discharge voltage to reach 5 V was about 2500 hours. In Example 2, it was about 2500 hours, and in Example 3, it was about 3000 hours.

As described above, regarding the deterioration of the protective film on the sustain electrode Y, the address electrode A-the sustain electrode Y
Inspection of the discharge voltage during the test showed that the use of the driving methods of Examples 1 to 3 clearly caused less deterioration than the conventional example, thereby enabling stable discharge and prolonging the life. Was proved.

In the above-described embodiment, the structure in which the dielectric layer and the protective film are laminated on the sustain electrode has been described. However, the present invention is not limited to this. For example, the protective film is formed in a thick layer and doubles as the dielectric layer. It is also possible to do so.

[0062]

According to the present invention, when a discharge cell to be lit is selected, an address discharge between the address electrode and the first main electrode and an address discharge between the address electrode and the second main electrode are performed. Are alternately generated at predetermined intervals, so that the deterioration of the protective film on the first main electrode and the deterioration of the protective film on the second main electrode can be made equal to each other.
Life can be extended.

[Brief description of the drawings]

FIG. 1 is a perspective view showing a configuration of a PDP to which a driving method according to the present invention is applied.

FIG. 2 is a circuit block diagram showing a configuration of a driving unit used in the driving method of the present invention.

FIG. 3 is an explanatory diagram showing an outline of a gradation driving method.

FIG. 4 is an explanatory diagram showing a driving waveform of a driving method according to the present invention.

FIG. 5 is an explanatory view showing a panel structure of the ALis method.

FIG. 6 is a graph showing a relationship between a driving time and an address discharge voltage.

FIG. 7 is a configuration diagram of a conventional plasma display device.

[Explanation of symbols]

 Reference Signs List 1 Y-side scanning driver 2 Y-side common driver 3 X-side scanning driver 4 X-side common driver 5 A-side driver 6 Control circuit 10, 20 PDP 11 Front-side substrate 12 Transparent electrode 13 Metal electrode (bus 17) Dielectric layer 18 Protective film 21 Backside substrate 22 Underlayer 24 Dielectric layer 28R, 28G, 28B Phosphor layer 29 Partition wall 30 Discharge space A Address electrode L Display line X, Y Sustain electrode

Continued on the front page F-term (reference) 5C080 AA05 BB05 CC03 DD18 DD29 EE29 EE30 FF07 FF12 HH02 HH04 JJ02 JJ04 JJ05 JJ06 KK02 KK43

Claims (2)

[Claims] 1. A semiconductor device comprising a pair of substrates in which discharge cells are arranged in a matrix between substrates, and one of the substrates has alternating first and second main electrodes for generating a main discharge for lighting the discharge cells. Are arranged in parallel and a protective film is formed thereon,
Also, when driving a plasma display panel having a structure in which address electrodes for generating an address discharge for selecting a discharge cell to be lit are arranged in parallel with a direction intersecting with the main electrode, the other substrate has a discharge to be lit. When selecting a cell, an address discharge between the address electrode and the first main electrode and an address discharge between the address electrode and the second main electrode are alternately generated at predetermined intervals. Of driving a plasma display panel. 2. A semiconductor device comprising: a pair of substrates in which discharge cells are arranged in a matrix between the substrates; and one of the substrates has alternating first and second main electrodes for generating a main discharge for lighting the discharge cells. Are arranged in parallel and a protective film is formed thereon,
A driving device for driving a plasma display panel having a structure in which address electrodes for generating an address discharge for selecting a discharge cell to be lit on the other substrate are arranged in parallel in a direction intersecting with the main electrode, A first address discharge generator for generating an address discharge between the address electrode and the first main electrode when selecting a discharge cell to be lit; an address electrode and a second main electrode when selecting a discharge cell to be lit; A second address discharge generating section for generating an address discharge between the electrodes, a control section for alternately switching an address discharge by the first address discharge generating section and an address discharge by the second address discharge generating section at predetermined intervals. A driving device for a plasma display panel comprising: