JPH04221992A - Method for driving plasma display panel - Google Patents

Abstract

PURPOSE:To facilitate the production of the plasma display panel and to decrease the number of parts of a driving circuit in the driving method for the plasma display panel which executes refresh display. CONSTITUTION:The driving method for the plasma display panel 1 which impresses driving voltages selectively to data side electrodes A and scan side electrodes K disposed like grids within a display screen H so as to make the display of the refresh system is constituted by segmenting the display screen H to plural regions h1, h2, successively selectively impressing the driving voltages at every unit display period T2 time-divided from a line display period T1 to plural pieces of the scan side electrodes K corresponding respectively to the respective regions h1, h2 and selectively impressing the driving voltages at every unit display period T2 in synchronization with the selection of the scan side electrodes K to the data side electrodes A.

Description

[Detailed description of the invention]

0001

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for driving a plasma display panel that performs refresh display.

As a display method for a plasma display panel (PDP) that displays characters and figures by combining dots (pixels) that emit light, there is a refresh display method that sequentially displays one screen line by line in a time-division manner.

[0003] The refresh display method can simplify the structure of the driving circuit compared to the memory display method, that is, the method in which the display started for each line is continued within the display period of one screen. Additionally, generally, DC (direct current) driven PDPs do not have a dielectric material with memory function inside the panel.
In this case, a refresh display method is used as the display method.

0004

2. Description of the Related Art In a PDP that performs refresh display, among the electrodes arranged in a grid (matrix), the electrodes extending in the line direction are called scan side electrodes, and the drive voltage is selectively applied to each line display period. applied. An electrode extending in a direction perpendicular to the scan side electrode is called a data side electrode, and a drive voltage is selectively applied based on display data.

Further, in a DC type PDP that performs display by applying a DC pulse voltage, the data side electrode is usually used as an anode electrode, and the scan side electrode is used as a cathode electrode. Then, a discharge occurs at the intersection (discharge cell) between the anode electrode and the cathode electrode to which a direct current voltage is selectively applied. One discharge cell corresponds to a dot.

FIG. 3 is a voltage waveform diagram showing a basic driving method of a DC type PDP.

At all times, that is, when no display is performed, the potential of the anode electrode is set to a bias potential (non-driving potential) vb1 of, for example, about 130 volts, and the potential of the cathode electrode is set to a bias potential (non-driving potential) of about 50 volts. vb2
It is said that At this time, a bias voltage Vb of about 80 volts is applied to the discharge cell, but since the bias voltage Vb is lower than the discharge start voltage Vf, no discharge occurs.

During display, the potential of the anode electrode is set to a driving potential va of, for example, about 200 volts, and the potential of the cathode electrode is set to the ground potential (driving potential on the cathode side). As a result, a drive voltage Va exceeding the discharge start voltage Vf is applied to the discharge cell, causing a discharge.

Note that the respective potentials of the anode electrode and the cathode electrode are controlled by a driver circuit consisting of a switching element.

FIG. 4 is a diagram showing an example of refresh display in a DC type PDP.

The example in FIG. 4 shows a so-called single-plex drive, and as shown in FIG. 4(a), scan-side electrodes x1 to x5 of m scan-side electrodes x1 to xm
and data side electrodes y1 to y5 of n data side electrodes y1 to yn, the discharge cells are made to emit light as shown by white circles in the figure to display the letter "M". be.

Referring also to FIG. 3, first, as shown in the time chart of FIG. 4(b), the scan side electrode x1 of the first line is selected and its potential is set to the ground potential for the line display period T1. . At the same time, the data side electrodes y1, y
The potential of No. 5 is set as the drive potential va. As a result, light emission occurs due to discharge in the two discharge cells defined at the intersection of the scan side electrode x1 and the data side electrodes y1 and y5, and the light emission continues during the line display period T1.

After the line display period T1 has elapsed, the second line is displayed, the potential of the scan side electrode x1 is returned to the normal bias potential vb2, and the potential of the scan side electrode x2 is changed to
is the ground potential. At the same time, the data side electrode y1,
y5 is selected successively from the first line, data side electrodes y2 and y4 are newly selected, and their respective potentials are set as the drive potential va. As a result, light emission occurs in the four discharge cells.

Thereafter, in each line display period T1, scan side electrodes x3, x4, x5 are sequentially selected corresponding to the display of the third to fifth lines, and in parallel, a predetermined data side electrode is selected. By selecting , a predetermined discharge cell is caused to emit light. Then, when the display of the mth line is completed, the display of the first line is performed again, and the display of lines 1 to m (
1 field) is repeated.

[0015] In the refresh display, as described above,
Each line emits light only during the line display period T1, which is divided into the display period (field period) of one screen, so the number of lines (
The display brightness decreases in inverse proportion to the number of scan-side electrodes. The maximum number of lines in practical use is about 800.

For this reason, conventionally, the number of lines is, for example, 1.
In large-sized PDPs that exceed 1,000 pixels, the entire display screen is displayed using a multiplex driving method in which the display screen is divided into a plurality of areas and each divided screen is displayed in parallel.

That is, for example, if the display screen is
In the case of division, the scan-side electrodes are divided into two groups of upper and lower electrodes, and a drive voltage is simultaneously applied to a total of two scan-side electrodes, one selected from each electrode group. In addition, each data side electrode is divided into an upper data side electrode and a lower data side electrode at the center in the vertical direction so as to correspond to the upper and lower scan side electrode groups, and the display data corresponding to the upper and lower parts are divided into upper and lower data side electrodes. A driving voltage is selectively applied based on.

In other words, the display screen is a composite screen in which two independently driven and controlled divided screens are closely spaced.

[0019]

Problems to be Solved by the Invention Even if the display screen is divided into a plurality of divided screens in terms of drive control, it must be a uniform screen as a whole in terms of display. Therefore, the distance between the scan-side electrode groups divided according to the division of the display screen must be equal to the distance between the scan-side electrodes. Normally, the spacing between scan side electrodes is 10
The thickness is selected to be approximately 0 to 120 μm.

Now, in the conventional multiplex driving method, as mentioned above, when dividing the data-side electrode in order to enable independent driving on the divided screen, an insulation gap (about 50 μm) is set to 2. It must be placed between the scan side electrodes of the book.

[0021] For this reason, since high precision is required for positioning the scan-side electrode and the data-side electrode, PD
There was a problem that P was difficult to manufacture. In addition, as the display screen is divided, the number of data-side electrodes increases (doubling when the display screen is divided into two), so the number of driver circuits required for each data-side electrode also increases, making it difficult to assemble the PDP drive circuit board. There was a problem that the man-hours were complicated.

Furthermore, if the data side electrode is divided into three or more electrodes, it becomes difficult to wire these electrodes, so it is practically impossible to divide the display screen into three or more screens, and the PDP Another problem was that it was not possible to further increase the size of the device.

SUMMARY OF THE INVENTION In view of the above-mentioned problems, it is an object of the present invention to facilitate the manufacture of a plasma display panel and to reduce the number of driving circuit parts.

[0024]

[Means for Solving the Problems] In order to solve the above-mentioned problems, the method according to the invention of claim 1 is directed to the data side arranged in a grid on the display screen H, as shown in FIGS. 1 and 2. A method for driving a plasma display panel 1 in which a driving voltage is selectively applied to an electrode A and a scan-side electrode K so as to perform refresh-type display, the display screen H being divided into a plurality of regions h1 and h2. and each area h
A drive voltage is sequentially and selectively applied to the plurality of scan-side electrodes K corresponding to each of the scan-side electrodes K in each unit display period T2 obtained by time-dividing the line display period T1, and the data-side electrode A On the other hand, a driving voltage is selectively applied every unit display period T2 in synchronization with the selection of the scan-side electrode K.

[0025] In the method according to the second aspect of the invention, the unit display period T2 is selected to be a time that does not cause discharge to transition to arc discharge.

In the method according to the third aspect of the invention, the line display period T1 is divided into a number that is twice or more the total number of the regions h1 and h2, and the data side electrode A is arranged within the line display period T1. The number of selections is changed for each data side electrode A.

In the method according to the fourth aspect of the present invention, a common power source 11, 12 is provided for each scan side electrode K, and the potentials of the power sources 11, 12 are changed to a driving potential and a non-driving potential for each unit display period T2. and alternately.

[0028]

[Operation] The line display period T1 is divided into a number of unit display periods T2 that are more than twice the total number of regions h1 and h2 that divide the display screen H, and during the unit display period T2, discharge shifts to arc discharge. The time (for example, about 1 .mu.s) is selected so that it does not occur.

In each area h1, h2, the line display period T
The display is performed so as to be sequentially switched every unit display period T2 obtained by time-dividing 1. At this time, gradation display is performed by changing the number of times the data side electrodes A1 to yn are selected within the line display period T1.

Each scan side electrode K has a unit display period T.
A driving voltage is commonly applied from power sources 11 and 12 whose potentials are alternately switched between a driving potential and a non-driving potential every 2 seconds.

[0031]

Embodiments Hereinafter, embodiments of the present invention will be described with reference to the drawings.

FIG. 2 is a plan view showing the electrode structure of the DC type PDP 1 according to the present invention.

The PDP 1 has a plurality of anode electrodes A extending in the vertical direction and parallel to each other, and 800 cathode electrodes K extending in the horizontal direction and parallel to each other. Anode electrode A is a data side electrode in refresh display,
The drive is controlled by an anode driver circuit 20 provided for each. Further, the cathode electrodes K are scan-side electrodes, and are driven and controlled by cathode driver circuits 10 provided respectively.

The anode electrode A and the cathode electrode K are arranged to face each other with a discharge space interposed therebetween, and discharge cells (not shown) are defined at each intersection of these electrodes, and the area where the discharge cells are defined is displayed on the display screen. It becomes H.

In the PDP 1, the display screen H is divided into two vertically adjacent areas h1 and h2, and each area h1,
At h2, time-division display is performed as described later.

400 cathode electrodes K (hereinafter referred to as "upper electrode group") from the 1st line to the 400th line correspond to the area h1, and 400 cathode electrodes K from the 401st line to the 800th line correspond to the area h2. corresponds to the cathode electrode K (hereinafter referred to as "lower electrode group").

Further, in the PDP 1, a common power supply 11 is provided for each cathode driver circuit 10 corresponding to the upper electrode group, and a common power supply 11 is provided for each cathode driver circuit 10 corresponding to the lower electrode group. A common power source 12 is provided for these.

FIG. 1 is a timing chart showing the driving method of the present invention.

In FIG. 1, as shown by white circles in FIG. 2, discharge cells in the first line, 2
It is assumed that the discharge cell on the 401st line in the column and the discharge cells on the 1st line and the 401st line in the 3rd column emit light.

Referring also to FIG. 4, in starting display, first, in the first line display period T1 of one field period, the first line and the 401st line, which are the first lines of areas h1 and h2, are displayed. Two cathode electrodes K are selected at the same time. That is, the cathode driver circuits 10 corresponding to these cathode electrodes K are turned on.

The on state of the cathode driver circuit 10 means that the potentials of the power supplies 11 and 12 are almost unchanged at the cathode electrode K.
This is a state where the potential is . On the other hand, the off-state of the cathode driver circuit 10 is a state in which the potential of the cathode electrode K becomes the bias potential vb1 (see FIG. 3).

The potentials of the power supplies 11 and 12 are alternately switched between a driving potential (ground potential) and a non-driving potential ( switching). That is, when the potential of the power source 11 is a driving potential (when turned on), the potential of the power source 12 is a non-driving potential, and when the potential of the power source 12 is a driving potential, the potential of the power source 11 is a non-driving potential,
Such potential relationship changes every unit display period T2.

Therefore, the potentials of the two selected cathode electrodes K are set during the line display period T1 so that when one potential is a driving potential, the other is a non-driving potential, as the power supplies 11 and 12 are switched. Unit display period T within
Switches alternately every 2.

On the other hand, the anode electrode A in the first row is turned on when the cathode electrode K in the first line is turned on, and the anode electrode A in the second row is turned on when the cathode electrode K in the 401st line is turned on. do. In addition, the third row of anode electrode A
is continuously turned on when the cathode electrode K of the first line or the 401st line is turned on, that is, as a result, during the line display period T1. As explained with reference to FIG. 3, when both the anode electrode A and the cathode electrode K are on, a voltage exceeding the discharge start voltage is applied to the discharge cell and a discharge occurs.

As a result, the two discharge cells in the region h1 and the two discharge cells in the region h2 each alternately emit light five times within the line display period T1.

Thereafter, in the second line display period T1 following the first line display period T1, the second line and 40
The cathode electrodes K on the second line are selected, and a driving voltage is applied to each cathode electrode K every unit display period T2. After that, one cathode electrode K is selected from the area h1 and the area h2 for each line display period T1, and one cathode electrode K is selected from the area h1 and the area h2.
Time-sharing display is performed for the area h2 and the area h2.

In the example shown in FIG. 1, the discharge cells are caused to emit light five times within the line display period T1, but the number of times the discharge cells emit light is selectively reduced to four or less times by on/off control of the anode driver circuit 20. be able to. That is, by changing the number of drive pulses applied to the anode electrode A for each column, gradation display can be performed.

Further, if the line display period T1 is time-divided so that the unit display period T2 is, for example, about 1 μs, a discharge current limiting resistor is not required in the anode driver circuit 20. That is, when the unit display period T2, which is one discharge time, is selected to be a relatively long time, a discharge current limiting resistor is required to prevent the discharge from transitioning to arc discharge. However, if the unit display period T2 is 1μ
If the time is selected to be approximately 1.5 seconds, the discharge will stop before it transitions to arc discharge, so there is no need to limit the discharge current. Further, by shortening the unit display period T2, only the light emitted at the initial stage of discharge is used for display, so that the light emission efficiency can be increased.

According to the above embodiment, the number of lines is 800.
Even so, since the line display period T1 is 1/400 of the display period of one screen, display brightness suitable for practical use can be obtained.

According to the above-described embodiment, when displaying is performed by dividing the display screen H into two areas h1 and h2, it is not necessary to divide the anode electrode A into upper and lower parts, so that the anode electrode A and the cathode electrode K By providing the same number of anode driver circuits 20 as in the case of single-plex drive, multiplex drive can be performed.

According to the embodiment described above, the potential of the cathode electrode K can be switched every unit display period T2 by switching the power supplies 11 and 12, so that each cathode driver circuit 10 has a No switching means is required.

In the above embodiment, the line display period T1 is divided into ten unit display periods T2, but the number of divisions of the line display period T1 may be an integral multiple or more of the number of divisions of the display screen. However, when performing gradation display, the number of divisions must be selected to be at least twice the number of divisions on the display screen.

In the above embodiment, a DC type PDP
1 was shown as an example, but AC using the refresh display method (
The present invention can also be applied to an AC type PDP.

In the above embodiment, the display screen H is divided into two
Although the display screen H is divided into two regions h1 and h2, the display screen H may be divided into three or more regions, and time-sharing display may be performed for each region.

In the above embodiment, the unit display period T2
can be changed as appropriate depending on the discharge characteristics determined by the discharge gap, the composition of the discharge gas, etc. Further, the number of cathode electrodes K and anode electrodes A, the circuit configurations of the cathode driver circuit 10 and the anode driver circuit 20, etc. can be selected as appropriate.

[0056]

According to the present invention, it is possible to facilitate the manufacture of a plasma display panel and to reduce the number of driving circuit parts.

According to the second aspect of the invention, when displaying by applying a DC voltage, with respect to the anode side electrode,
There is no need to provide a resistor to limit the discharge current, and the drive circuit can be simplified.

According to the third aspect of the invention, gradation display can be easily performed.

According to the invention of claim 4, when the display screen is divided into two, it is no longer necessary to provide each scan-side electrode with a switching means for switching the drive voltage for each unit display period, and the drive circuit is Simplification can be achieved.

[Brief explanation of the drawing]

FIG. 1 is a timing chart showing a driving method of the present invention.

FIG. 2 is a plan view showing an electrode structure of a DC type PDP according to the present invention.

FIG. 3 is a voltage waveform diagram showing a basic driving method of a DC type PDP.

FIG. 4 is a diagram showing an example of a refresh display in a DC type PDP.

[Explanation of symbols]

1 PDP (plasma display panel) A Anode electrode (data side electrode) K Cathode electrode (scan side electrode) H Display screen h1, h2 Area T1 Line display period T2 Unit display period 11, 12 Power supply

Claims (4)

[Claims] Claim 1: With respect to data-side electrodes (A) and scan-side electrodes (K) arranged in a grid on a display screen (H),
A method for driving a plasma display panel (1) in which a driving voltage is selectively applied to perform refresh-type display, the display screen (H) being divided into a plurality of areas (h1).
(h2), and a unit display period (T2) obtained by time-dividing the line display period (T1) for the plurality of scan side electrodes (K) corresponding to each of the regions (h1) and (h2). ), and selectively drive the data side electrode (A) every unit display period (T2) in synchronization with the selection of the scan side electrode (K). A method for driving a plasma display panel, the method comprising applying a voltage. 2. The method of driving a plasma display panel according to claim 1, wherein the unit display period (T2) is selected to a length of time that does not cause discharge to transition to arc discharge. 3. The line display period (T1) is divided into a number that is twice or more the total number of the respective regions (h1) (h2),
The data side electrode (A
2. The method for driving a plasma display panel according to claim 1, wherein the number of selections of ) is changed for each data-side electrode (A). 4. A common power source (11) (12) is provided for each scan side electrode (K), and the power source (11) (12)
2. The method of driving a plasma display panel according to claim 1, wherein the potential of the plasma display panel is alternately switched between a driving potential and a non-driving potential every unit display period (T2).