KR100397429B1 - Plasma display Panel and Driving Method Thereof - Google Patents

Abstract

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a plasma display panel and a driving method thereof in which the size of the discharge cells can be the same, and the brightness, efficiency, and life can be improved by using the data electrodes during the sustain discharge.

According to the present invention, a plasma display panel includes a discharge cell in which red, green, and blue cells are arranged in the same size on a lower substrate, a data electrode for selecting discharge cells, and a floating voltage supplied to the data electrode during a sustain period. Switch means for selectively switching the ground voltage and zero voltage is provided.

The driving method of the plasma display panel according to the present invention includes supplying a floating voltage to the data electrode while the sustain discharge voltage pulse is applied from the start of the sustain period in the address period.

According to the configuration of the present invention, the blue data electrode is always floated during the sustain period of the data electrodes, thereby improving the luminance intensity of blue, thereby improving luminance, efficiency, and lifetime.

Since the size of the discharge cell can be the same by this driving method, it can be easily applied to a high definition (HD) class plasma display panel.

Description

Plasma Display Panel and Driving Method Thereof

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a plasma display panel, and more particularly, to a plasma display panel and a driving method thereof in which the size of a discharge cell can be the same, and the brightness, efficiency, and life can be improved by using a data electrode during sustain discharge.

Plasma Display Panel (hereinafter referred to as "PDP") is a display device using visible light generated from a phosphor when vacuum ultraviolet rays generated by gas discharge excite the phosphor. PDP is thinner and lighter than Cathode Ray Tube (CRT), which has been the mainstay of display means, and has the advantage of being able to realize high-definition large screen. The PDP is composed of a plurality of discharge cells arranged in a matrix form, and one discharge cell forms one pixel of the screen.

1 is a perspective view showing a discharge cell structure of a conventional three-electrode AC surface discharge type PDP.

Referring to FIG. 1, a discharge cell of a conventional three-electrode AC surface discharge type PDP includes a scan / sustain electrode 12Y and a common sustain electrode 12Z formed on an upper substrate 10, and a lower substrate 18. The formed data electrode 20X is provided.

The upper dielectric layer 14 and the passivation layer 16 are stacked on the upper substrate 10 having the scan / sustain electrode 12Y and the common sustain electrode 12Z side by side. In the upper dielectric layer 14, wall charges generated during plasma discharge are accumulated.

The protective layer 16 prevents damage to the upper dielectric layer 14 due to sputtering generated during plasma discharge and increases discharge efficiency of secondary electrons. As the protective film 16, magnesium oxide (MgO) is usually used.

The lower dielectric layer 22 and the partition wall 24 are formed on the lower substrate 18 on which the data electrode 20X is formed, and the phosphor layer 26 is coated on the lower dielectric layer 22 and the partition wall 24.

The data electrode 20X is formed in the direction crossing the scan / sustain electrode 12Y and the common sustain electrode 12Z. The partition wall 24 is formed in parallel with the data electrode 20X to prevent ultraviolet rays and visible light generated by the discharge from leaking to the adjacent discharge cells.

The phosphor layer 26 is excited by ultraviolet rays generated during plasma discharge to generate visible light of any one of red, green, and blue. Inert gas for gas discharge is injected into the discharge space provided between the upper substrate 10 / lower substrate 18 and the partition wall 24.

The AC surface-discharge type PDP is driven by an ADS (Address and Display Period Separated) method in which one frame is divided into several subfields having different number of discharge times to express gray level of an image. In the ADS method, the display quality is mostly determined by the state of the sustain discharge. In particular, the brightness, efficiency, and lifespan of the display discharge are considerably large.

Each subfield is further divided into a reset period for uniformly causing discharge, an address period for selecting a discharge cell, and a sustain period for expressing gray scale according to the number of discharges. For example, when the image is to be displayed with 256 gray levels, the frame period (16.67 ms) corresponding to 1/60 second is divided into eight subfields. In addition, each of the eight subfields is subdivided into an address period and a sustain period. Here, the reset period and the address period of each subfield are the same for each subfield, while the sustain period is 2 ⁿ (n in each subfield). = 0,1,2,3,4,5,6,7). In this way, since the sustain period is different in each subfield, the gray level of the image can be expressed.

Here, in the reset period, a reset pulse is supplied to the scan / sustain electrode 12Y to generate a reset discharge. In the address period, scan pulses are supplied to the scan / sustain electrodes 12Y, and data pulses are supplied to the data electrodes 20X to generate address discharges between the two electrodes 12Y and 20X. During the address discharge, wall charges are formed in the upper and lower dielectric layers 14 and 22. In the sustain period, sustain discharge is generated between the two electrodes 12Y and 12Z by an alternating current signal alternately supplied to the scan / sustain electrode 12Y and the common sustain electrode 12Z as shown in FIGS. At this time, the data electrode 20X is maintained at a bias of zero voltage (0V) during the sustain discharge period, and the voltage applied until the data write function is always constant. In the sustain discharge period, the electric field interference is caused between the data electrode 20X and the scan / sustain electrode 12Y and the common sustain electrode 12Z.

As a result, some of the positive charges propagate toward the phosphor 26. Therefore, since some of the positive charges damage the phosphor 26, the luminous efficiency of the phosphor 26 is lowered. In particular, the blue (B) phosphor 26 has a problem of aging faster due to the difference in characteristics of the phosphor composition than the phosphors of other colors.

In addition, the size of the discharge cells of the PDP is formed differently according to the luminance intensity of the red (R), green (G), blue (B) in order to match the white balance (White Valance).

Referring to FIG. 4, in order to match the white balance of the PDP, the sizes of the discharge cells 30, 31, and 32 are green (the largest luminance intensity among the phosphors of red (R), green (G), and blue (B)). The discharge cell 32 of G) has the smallest size, and the discharge cell 30 of blue (B) having the smallest luminance intensity is formed with the largest size. The red (R) discharge cell 31 is formed to have an intermediate size between the blue (B) discharge cell 30 and the green (G) discharge cell 32. By setting the sizes of the blue discharge cells 30, the green discharge cells 31, and the red discharge cells 32 of the discharge cells differently, the brightness, efficiency, and lifetime of the PDP are improved.

However, the conventional PDP has a problem that it is difficult to be applied to a high definition (HD) -class resolution PDP in which the size of the discharge cell must be smaller because the size of the blue (B) discharge cell 30 is larger than that of the discharge cell of another color.

Accordingly, it is an object of the present invention to provide a plasma display panel and a driving method thereof in which the size of the discharge cells can be the same, and the brightness, efficiency, and life can be improved by using the data electrodes during the sustain discharge.

1 is a view showing a conventional plasma display panel.

Fig. 2 is a diagram showing the structure of an alternating surface discharge plasma display panel.

3 shows a conventional sustain discharge.

4 is a diagram showing conventional red, green and blue cell sizes.

5 is a view showing the conditions of the basic data electrode in the sustain discharge period according to an embodiment of the present invention.

6A to 6H are waveform diagrams showing conditions of the data electrodes shown in FIG.

7 illustrates a structure of a plasma display panel according to the present invention.

8 shows conditions of a basic data electrode in a sustain discharge period.

9 is a graph showing the luminance intensity of blue under the conditions of the basic discharge voltage.

10 is a graph showing the optical efficiency according to the condition of the basic discharge voltage.

11 is a graph showing luminance according to a condition of a basic discharge voltage.

12 is a graph showing a discharge voltage according to a condition of a basic discharge voltage.

Fig. 13 is a graph comparing the lifespan between the prior art and the present invention.

14 is a graph comparing luminance according to red, green, and blue conditions, respectively.

15 is a graph comparing color coordinates according to red, green, and blue conditions, respectively.

16 is a graph comparing color temperatures according to red, green, and blue conditions, respectively.

17 is a graph comparing discharge voltages according to red, green, and blue conditions, respectively.

18 is a graph comparing optical efficiency according to red, green, and blue conditions, respectively.

19 is a graph comparing discharge currents according to red, green, and blue conditions, respectively.

<Explanation of symbols for major parts of drawings>

10: upper substrate 12Y, 40: scan / sustain electrode

12Z, 42 common sustain electrode 14,22 dielectric layer

16: protective film 18: lower substrate

20X, 46: Data electrode 24,44: Bulkhead

26 phosphor layer 30 blue cell

31: green cell 32: red cell

SW: selector switch

In order to achieve the above object, a plasma display panel according to the present invention comprises a discharge cell in which red, green, and blue cells are arranged in the same size on a lower substrate, a data electrode for selecting discharge cells, and data during a sustain period. And switching means for selectively switching the floating voltage, the ground voltage, and the zero voltage supplied to the electrode.

A method of driving a plasma display panel according to the present invention includes supplying a floating voltage to a data electrode while a sustain discharge voltage pulse is applied from the start of the sustain period in an address period.

Other objects and features of the present invention in addition to the above object will be apparent from the description of the embodiments with reference to the accompanying drawings.

Hereinafter, exemplary embodiments of the present invention will be described with reference to FIGS. 5 to 19.

In the present invention, while the reset period and the address period are the same as compared with the conventional ADS method, the sustain discharge period is controlled differently from the bias condition of the data electrode as shown in FIG.

5 is a view showing basic data electrode conditions in the sustain discharge period according to the present invention.

Referring to FIG. 5, the blue data electrode 46B is always floating during the sustain discharge period, and the floating voltage, the ground voltage, and the zero voltage are selected for the green data electrode 46G and the red data electrode 46R. The bias conditions of the data electrode 46 are shown in Table 1 below.

Bias Condition of Data Electrode Bias condition Red (R) data electrode Green (G) Data Electrode Blue (B) data electrode One Floating Floating Floating 2 Floating Ground Floating 3 Floating 0 V Floating 4 Ground Floating Floating 5 Ground Ground Floating 6 Ground 0 V Floating 7 0 V Floating Floating 8 0 V Ground Floating 9 0 V 0 V Floating

The waveform diagrams of the bias conditions of the data electrodes are shown in FIGS. 6A to 6H.

6A to 6H, FIG. 6A shows red, green, and blue colors while a sustain discharge voltage pulse is applied within 5 pulses instead of bringing the data electrode condition to zero voltage immediately after entering the sustain discharge period in the address period. By keeping all of the data electrodes 46R, 46G, and 46B in a floating state, the luminance intensity is increased from the conventional zero voltage application state, and the optical efficiency, discharge voltage, color temperature, and discharge current are improved than the conventional zero voltage application state. .

FIG. 6B shows the bias condition 2 in Table 1, where the blue and red data electrodes maintain the floating state, and the green data electrodes maintain the ground state, thereby increasing the luminance intensity over the conventional zero voltage application state and also performing color coordinates. The color temperature is improved over the conventional zero voltage application state.

6C shows the bias condition 3 in Table 1, wherein the blue and red data electrodes maintain the floating state, and the green data electrodes maintain the zero voltage state, thereby increasing the luminance intensity over the conventional zero voltage application state. The color coordinates and color temperature are improved over the conventional zero voltage application state.

6D shows the bias condition 4 in Table 1, where the blue and green data electrodes maintain the floating state, and the red data electrodes maintain the ground state, thereby increasing the luminance intensity over the conventional zero voltage application state, as well as the color coordinates. The color temperature, the discharge current, and the optical efficiency are improved over the conventional zero voltage application state.

6E shows the bias condition 7 in Table 1, where the blue and green data electrodes maintain the floating state, and the red data electrodes maintain the zero voltage state, thereby increasing the luminance intensity over the conventional zero voltage application state. The color coordinates and color temperature are improved over the conventional zero voltage application state.

6F shows that the blue and green data electrodes maintain a floating state, and the red data electrodes maintain a bias voltage state, whereby the luminance intensity is increased from the conventional zero voltage application state, and the color temperature and discharge current are applied to the conventional zero voltage application state. Is improved.

6G shows that the blue and red data electrodes maintain a floating state and the green data electrodes maintain a bias voltage state, so that the luminance intensity is similar to the conventional zero voltage application state, but the color coordinates and color temperature are improved over the conventional zero voltage application state. do.

6H illustrates a condition in which the blue data electrode maintains a floating state and the red and green data electrodes have a bias voltage state.

Such a bias condition may be selectively applied according to the panel condition and the circuit control method of the PDP panel.

7 illustrates a structure of a plasma display panel according to a second embodiment of the present invention.

Referring to FIG. 7, the discharge cells are formed in the same size, and are electrically connected to the data electrodes 46 and include a switching switch SW for selecting a floating voltage or a ground voltage according to a bias condition.

The changeover switch SW is turned on / off from an output terminal on the panel according to a bias condition to simultaneously supply a floating voltage, a ground voltage or a zero voltage to the data electrode line. During the sustain discharge period, the blue data electrode 46B is connected to the switching switch SW and is always supplied with the floating voltage Vf during the discharge period. The green data electrode 46G and the red data electrode 46R depend on the bias conditions. The floating voltage Vf, ground voltage or zero voltage are supplied. The floating voltage of the blue data electrode 46B is set lower than the bias voltages of the red data electrode 46R and the green data electrode 46G used in the address period.

FIG. 8 is a waveform diagram illustrating a change in the condition of the green and red data electrodes after the initial floating state of the data electrodes in the sustain discharge period. The bias conditions shown in Table 1 may be applied.

Referring to FIG. 8, the data electrode maintains the floating state of the data electrode while the sustain discharge voltage pulse is applied within about 5 pulses instead of bringing the voltage to zero immediately when the sustain discharge period is suppressed in the address period. After maintaining the floating state, the blue data electrode always maintains the floating state, while the green and red data electrodes receive the bias voltage according to the respective conditions.

As described above, by floating the blue data electrode at all times, the luminance intensity of the blue phosphor is improved to improve the white balance, efficiency and lifetime of the PDP panel. The white balance, the lifespan, and the efficiency of the PDP panel due to the improvement in the luminance intensity of the blue phosphor will be described with reference to FIGS. 9 to 19.

FIG. 9 is a graph showing blue spectra of blue data electrodes according to floating, ground, zero voltage, discharge voltage / 2, and discharge voltage. The X axis represents wavelength and the Y axis represents luminance intensity.

Referring to FIG. 9, a curve (A) shown by supplying a floating voltage to the blue data electrode and a curve (B) shown by supplying a ground voltage, zero voltage, and discharge voltage / 2 or discharge voltage to the blue data electrode are compared. It can be seen that the curve A has a higher luminance intensity than the curve B.

FIG. 10 is a graph showing optical efficiency obtained by supplying a voltage of a basic data condition to a data electrode, wherein the X axis represents red, green, and blue bias conditions, and the Y axis represents optical efficiency.

Referring to FIG. 10, the optical efficiency of applying the floating voltage FFF to the data electrode is the case of applying the zero voltage (000) to the conventional red, green, and blue data electrodes, and the case of applying the ground voltage (GGG). And, it can be seen that the improvement when the discharge voltage (Vs / 2Vs / 2Vs / 2) of the half and the discharge voltage (VsVsVs) is applied.

FIG. 11 is a graph showing luminance caused by supplying a voltage of a basic data condition to a data electrode, with the X axis representing red, green, and blue bias conditions, and the Y axis representing luminance.

Referring to FIG. 11, the luminance of applying the floating voltage FFF to the data electrode is different from the case of applying the zero voltage (000) to the conventional red, green, and blue data electrodes, and the case of applying the ground voltage GGG. In this case, it can be seen that the case of applying the discharge voltage (Vs / 2Vs / 2Vs / 2) of half and the case of applying the discharge voltage (VsVsVs) is improved.

FIG. 12 is a graph showing discharge voltages generated by supplying voltages of basic data conditions to the data electrodes, in which the X axis represents red, green, and blue bias conditions, and the Y axis represents discharge voltages Vs and floating voltages Vf.

Referring to FIG. 12, the floating discharge voltage FFF at the floating voltage Vf is a case in which the zero voltage (000) is applied to the conventional red, green, and blue data electrodes, and the ground voltage (GGG) is applied. And, it can be seen that the case of applying the discharge voltage (Vs / 2Vs / 2Vs / 2) of half and lower than when applying the discharge voltage (VsVsVs).

In addition, the floating discharge voltage FFF at the discharge voltage Vs is half that of the case of applying the zero voltage (000) to the conventional red, green, and blue data electrodes, and the case of applying the ground voltage (GGG). It can be seen that the case where the discharge voltage (Vs / 2Vs / 2Vs / 2) is applied and lower than when the discharge voltage (VsVsVs) is applied.

FIG. 13 is a graph comparing the prior art and the present invention in which a floating voltage is supplied to a data electrode and a lifetime, in which the X axis represents time and the Y axis represents luminance.

Referring to FIG. 13, the luminance of the initial state in which the floating voltage FFF is applied to the data electrode is lower than that in the case where the ground voltage GGG is applied to the red, green, and blue data electrodes. However, when the use time is about 100 hours, the conventional luminance is significantly lowered, but the amount of reduction of the present invention is reduced.

In addition, when the use time is about 880 hours, the conventional luminance decreases rapidly. However, the luminance of the present invention is reduced, the effect is superior to the conventional.

FIG. 14 is a graph illustrating luminance caused by supplying voltages of data R, G, and B bias conditions to the data electrodes, in which the X axis represents red, green, and blue bias conditions, and the Y axis represents luminance.

Referring to FIG. 14, it can be seen that the luminance 1 of the present invention which supplies the floating voltage to the red, green and blue data electrodes is higher than the conventional luminance 3 to which the zero voltage is supplied to the red, green and blue data electrodes. In addition, it can be seen that all of the discharge voltages 1 are higher than the conventional discharge voltage 1 under other bias conditions 6 to 20 that supply the floating voltage only to the blue data electrode.

FIG. 15 is a graph showing color coordinates caused by supplying voltages of data (R, G, B) bias conditions to the data electrodes, wherein the X axis represents red, green, and blue bias conditions, and the Y axis represents color coordinates.

Referring to FIG. 15, the X-axis and Y-axis coordinates of the present invention supplying a floating voltage to the red, green, and blue data electrodes rather than the conventional discharge voltage 3, in which zero voltages are supplied to the red, green, and blue data electrodes. 1) It can be seen that both are low, and even lower than the conventional X-axis and Y-axis coordinates 3 even in the bias conditions (6 to 20) of supplying the floating voltage only to the blue data electrodes.

FIG. 16 is a graph showing a color temperature caused by supplying voltages of data (R, G, B) bias conditions to the data electrodes, wherein the X axis represents red, green, and blue bias conditions, and the Y axis represents color temperatures.

Referring to FIG. 16, the color temperature 1 of the present invention for supplying the floating voltage to the red, green and blue data electrodes is higher than the conventional discharge voltage 3 for supplying the zero voltage to the red, green and blue data electrodes. It can be seen that even under the bias conditions (6 to 20) of supplying the floating voltage only to the blue data electrode, all of them are higher than the conventional color temperature (3).

FIG. 17 is a graph showing discharge voltages generated by supplying data (R, G, B) bias conditions to the data electrodes, wherein the X axis represents red, green, and blue bias conditions, and the Y axis represents discharge voltages.

Referring to FIG. 17, the discharge voltage 1 of the present invention which supplies the floating voltage to the red, green and blue data electrodes is lower than the conventional discharge voltage 3 where the zero voltage is supplied to the red, green and blue data electrodes. You can see that.

FIG. 18 is a graph showing optical efficiency obtained by supplying a bias condition voltage to a data electrode, in which the X axis represents red, green, and blue bias conditions, and the Y axis represents optical efficiency.

Referring to FIG. 18, the optical efficiency of the present invention in which the floating voltage FFF is supplied to the red, green, and blue data electrodes is higher than that of the conventional discharge voltage (000) where the zero voltage is supplied to the red, green, and blue data electrodes. It can be seen that even under the bias conditions (GFF, 0GF) for supplying the floating voltage only to the blue data electrode, it is higher than the conventional discharge voltage (000).

19 is a graph showing a discharge current caused by supplying a bias condition voltage to the data electrode, with the X axis representing the red, green, and blue bias conditions, and the Y axis representing the discharge current.

Referring to FIG. 19, the discharge current of the present invention in which the floating voltage FFF is supplied to the red, green, and blue data electrodes is higher than the conventional discharge current (000) in which the zero voltage is supplied to the red, green, and blue data electrodes. It can be seen that even under the bias conditions (GFF to Vs / 20F) for supplying the floating voltage only to the blue data electrode, all of them are higher than the conventional discharge current (000).

Therefore, as a first embodiment of the present invention, the floating voltage FFF is supplied to the data electrode, thereby showing better characteristics than those of the related art in luminance, optical efficiency, color temperature, discharge voltage, and color coordinates.

As such, by adjusting the white balance using the data electrode, brightness, efficiency and lifespan can be improved, and the size of the discharge cell should be reduced by designing the same size of the red, green, and blue discharge cells. It can be easily applied to PDP resolution.

As described above, the data electrode formed on the lower substrate by the method of driving the plasma display panel according to the present invention is always floated on the blue data electrode during the sustain discharge period, thereby improving the luminance intensity of blue, thereby improving white balance, efficiency and lifetime. There is an advantage to improve. In addition, when entering the sustain discharge period from the address period, it is in a floating state, and the bias is applied according to each condition, so the discharge voltage is generated at the lower side, so that the discharge can be stably generated. do.

Since the size of the discharge cell can be the same by this driving method, it can be easily applied to HD (High Definition) class PDP.

Those skilled in the art will appreciate that various changes and modifications can be made without departing from the technical spirit of the present invention. Therefore, the technical scope of the present invention should not be limited to the contents described in the detailed description of the specification but should be defined by the claims.

Claims (7)

A discharge cell in which red, green, and blue cells are arranged on the lower substrate with the same size; A data electrode for selecting the discharge cells; And switch means for selectively switching the floating voltage, the ground voltage and the zero voltage supplied to the data electrode during the sustain discharge period. The method of claim 1, And said switch means is switched to supply a floating voltage to a blue data electrode during said sustain discharge period. The method of claim 1, And the switch means is switched to selectively supply one of a floating voltage, a ground voltage, and a zero voltage to the red and green data electrodes. In a driving method of a plasma display panel including a reset period, an address period and a sustain period, And supplying a floating voltage to a data electrode while the sustain discharge voltage pulse is applied from the start of the sustain period in the address period. The method of claim 4, wherein And the data electrodes are formed of red, green, and blue data electrodes, respectively, and the floating voltage is supplied to the blue data electrodes during a sustain discharge period. The method of claim 5, And one of a floating voltage, a ground voltage, and a zero voltage is selectively supplied to the red and green data electrodes. The method of claim 4, wherein And the floating voltage of the blue data electrode is lower than the bias voltages of the red and green data electrodes used in the address period.