KR100811549B1 - Plasma Display Apparatus - Google Patents

Abstract

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a Plasma Display Apparatus, and has an effect of increasing brightness of an image implemented by changing a sustain signal in relation to an average power level.

Such a plasma display device according to an embodiment of the present invention includes a plasma display panel having a first electrode and a second electrode parallel to each other, and a sustain signal to at least one of the first electrode and the second electrode in a sustain period for displaying an image. Supplies a first type sustain signal to at least one of the first electrode and the second electrode when the average power level is the first level, and the second power having the average power level higher than the first level. In the case of a level, a driving unit is configured to supply a second type sustain signal different from the first type sustain signal to at least one of the first electrode and the second electrode, wherein the sustain signal includes a voltage rising period, a voltage holding period, and a voltage falling period. Wherein the length of the voltage rise period of the second type sustain signal is equal to the voltage rise of the first type sustain signal. It is longer than the length of the period, and the length of the voltage drop period of the first type sustain signal is shorter than the length of the voltage drop period of the second type sustain signal.

Description

Plasma Display Apparatus {Plasma Display Apparatus}

1 is a view for explaining the configuration of a plasma display device according to an embodiment of the present invention.

2A to 2B are views for explaining an example of a plasma display panel that can be included in a plasma display device according to an embodiment of the present invention.

FIG. 3 is a diagram for explaining a frame for implementing gradation of an image in a plasma display device according to an embodiment of the present invention; FIG.

4 is a view for explaining an example of the operation of the plasma display device according to an embodiment of the present invention.

5A to 5B are diagrams for explaining another form of the rising ramp signal or the second falling ramp signal.

6 is a diagram for explaining an average power level.

7A to 7B are diagrams for explaining an example of a method of changing the sustain signal in relation to the average power level.

8A to 8B are views for explaining the form of discharge at the first level or the second level.

9 is a view for explaining an example of the configuration of a drive unit for supplying a sustain signal.

10 is a view for explaining an example of the operation of the driving unit in FIG. 9;

11 is a diagram for explaining an example of still another configuration of a drive unit;

<Description of the numbers for the main parts of the drawings>

100: plasma display panel 110: driver

The present invention relates to a plasma display device (Plasma Display Apparatus).

The plasma display apparatus includes a plasma display panel having electrodes formed thereon, and a driving unit supplying predetermined driving signals to the electrodes of the plasma display panel.

In general, a phosphor layer is formed in a discharge cell (Cell) partitioned by a partition, and a plurality of electrodes are formed in the plasma display panel.

The driver supplies a driving signal to the discharge cell through the electrode.

Then, the discharge is generated by the drive signal supplied in the discharge cell. Here, when discharged by a drive signal in the discharge cell, the discharge gas filled in the discharge cell generates vacuum ultraviolet rays, and the vacuum ultraviolet light emits the phosphor formed in the discharge cell to emit visible light. Generate. The visible light displays an image on the screen of the plasma display panel.

On the other hand, the conventional plasma display device has a problem that the brightness of the image implemented on the screen is lowered.

In order to solve the above problems, an object of the present invention is to provide a plasma display apparatus for improving the luminance of an image implemented by changing a sustain signal in relation to average power level (APL).

A plasma display device according to an embodiment of the present invention for achieving the above object is a plasma display panel having a first electrode and a second electrode parallel to each other, and one of the first electrode or the second electrode in the sustain period for displaying an image When the sustain signal is supplied and the average power level is the first level, the first type sustain signal is supplied to at least one of the first electrode and the second electrode, and the average power level is the first level. In the case of a higher second level, the driver includes a driver for supplying a second type sustain signal different from the first type sustain signal to at least one of the first electrode and the second electrode, wherein the sustain signal includes a voltage rising period and a voltage holding period. , The voltage drop period, and the length of the voltage rise period of the second type sustain signal is the first type sustain. Long, more than the length of the rising period of the signal, the first type of long voltage falling period of the sustain signal is characterized in that it is shorter than the length of the voltage falling period of the second type of a sustain signal.

In the second type sustain signal, a voltage difference between the first electrode and the second electrode increases in a voltage rising period of the sustain signal supplied to at least one of the first electrode and the second electrode.

In the first type sustain signal, a voltage difference between the first electrode and the second electrode increases in a voltage drop period of the sustain signal supplied to at least one of the first electrode and the second electrode.

Further, in the second type sustain signal, the voltage rises to the first voltage in the voltage rise period of the sustain signal supplied to at least one of the first electrode and the second electrode, and the first voltage to the second voltage lower than the first voltage. It falls, and it rises to the 3rd voltage higher than a 1st voltage from a 1st voltage.

In addition, the driving unit may sustain signals to at least one of the first electrode and the second electrode by using an energy recovery circuit including an energy supply path including a first inductor unit and an energy recovery path including a second inductor unit. Is supplied, and an inductance value of the second inductor unit is greater than an inductance value of the first inductor unit.

In addition, the inductance value of the second inductor unit may be approximately two times or more and three times or less the inductance value of the first inductor unit.

Hereinafter, a plasma display device according to an embodiment of the present invention will be described in detail with reference to the accompanying drawings.

1 is a view for explaining the configuration of a plasma display device according to an embodiment of the present invention.

1, a plasma display apparatus according to an embodiment of the present invention includes a plasma display panel 100 and a driver 110.

The driver 110 supplies a sustain signal to at least one of the first electrode and the second electrode included in the plasma display panel 100 in the sustain period for displaying an image, and has an average power level (APL). In the case of the first level APL 1, the first type (Type 1) sustain signal is supplied to at least one of the first electrode and the second electrode, and the second power level is higher than the first level APL 1. In the case of APL 2), a second type (Type 2) sustain signal different from the first type (Type 1) sustain signal is supplied to at least one of the first electrode and the second electrode.

Here, the sustain signal includes a voltage rising period, a voltage holding period, and a voltage falling period, and the length of the voltage rising period of the second type sustain signal is longer than the length of the voltage rising period of the first type sustain signal, and the first type. The length of the voltage drop period of the sustain signal is preferably shorter than the length of the voltage drop period of the second type sustain signal.

Here, in FIG. 1, only the case in which the driving unit 110 is formed in one board form is illustrated, but in the present invention, the driving unit 110 is divided into a plurality of board forms according to electrodes formed on the plasma display panel 100. It is also possible to lose.

For example, a first electrode and a second electrode parallel to each other and a third electrode crossing the first electrode and the second electrode are parallel to each other in the plasma display panel 100 included in the plasma display apparatus according to an embodiment of the present invention. In this case, the driving unit 110 includes a first driving unit (not shown) for driving the first electrode, a second driving unit (not shown) for driving the second electrode, and a third driving unit for driving the third electrode. It can be divided into (not shown).

The driving unit 110 will be more clearly described later.

Here, the plasma display panel 100 includes an electrode, which will be described in detail with reference to FIGS. 2A to 2B attached to an example of the plasma display panel 100.

2A to 2B are views for explaining an example of a plasma display panel that may be included in a plasma display device according to an embodiment of the present invention.

First, referring to FIG. 2A, a plasma display panel that may be included in a plasma display apparatus according to an exemplary embodiment of the present invention includes a front substrate on which first electrodes 202 and Y and second electrodes 203 and Z are parallel to each other. 201 and the rear substrate 211 formed with the third electrodes 213 and X crossing the first and second electrodes 202 and Y and the second and second electrodes 203 and Z may be bonded to each other.

Here, the electrodes formed on the front substrate 201, preferably the first electrodes 202 and Y and the second electrodes 203 and Z, generate a discharge in a discharge space, that is, a discharge cell, and discharge the same. The discharge of the cell can be maintained.

The dielectric layer covers the first electrode 202 and the second electrode 203 and Z on the front substrate 201 where the first electrode 202 and the second electrode 203 and Z are formed. Preferably, the upper dielectric layer 204 can be formed.

This upper dielectric layer 204 limits the discharge current of the first electrode 202, Y and the second electrode 203, Z and between the first electrode 202, Y and the second electrode 203, Z. Can be insulated.

A protective layer 205 is formed on the top surface of the upper dielectric layer 204 to facilitate discharge conditions. The protective layer 205 may be formed through a method of depositing a material such as magnesium oxide (MgO) on the upper dielectric layer 204.

On the other hand, the electrode, preferably the third electrode (213, X) is formed on the back substrate 211, the third electrode 213, is formed on the upper side of the back substrate 211, the third electrode (213, X) is formed A dielectric layer, preferably lower dielectric layer 215 may be formed to cover X).

The lower dielectric layer 215 may insulate the third electrodes 213 and X.

On top of the lower dielectric layer 215, a partition 212, such as a stripe type, a well type, a delta type, a honeycomb type, for partitioning a discharge cell, that is, a discharge cell, is formed. Can be formed. Accordingly, discharge cells such as red (R), green (G), and blue (B) may be formed between the front substrate 201 and the rear substrate 211.

In addition to the red (R), green (G), and blue (B) discharge cells, it is also possible to further form a white (W) or yellow (Yellow: Y) discharge cell.

On the other hand, the pitch of the red (R), green (G) and blue (B) discharge cells in the plasma display panel included in the plasma display device according to an embodiment of the present invention may be substantially the same, The pitches of the red (R), green (G) and blue (B) discharge cells may be different to match the color temperature in the red (R), green (G) and blue (B) discharge cells.

In this case, the pitch may be different for each of the red (R), green (G), and blue (B) discharge cells, but the pitch of one or more discharge cells among the red (R), green (G), and blue (B) discharge cells. May be different from the pitch of other discharge cells. For example, the pitch of the red (R) discharge cells is the smallest, and the pitch of the green (G) and blue (B) discharge cells may be larger than the pitch of the red (R) discharge cells.

Here, the pitch of the green (G) discharge cells may be substantially the same as or different from the pitch of the blue (B) discharge cells.

In addition, the plasma display panel included in the plasma display apparatus according to the exemplary embodiment of the present invention may have not only the structure of the partition wall 212 illustrated in FIG. 2A but also the structure of the partition wall having various shapes. For example, the partition 212 includes a first partition 212b and a second partition 212a, where the height of the first partition 212b and the height of the second partition 212a are different from each other. At least one of the first barrier rib 212b and the second barrier rib 212a, and a channel type barrier rib structure having a channel usable as an exhaust passage, at least one of the first barrier rib 212b and the second barrier rib 212a. Grooved partition wall structure having a groove formed in the groove will be possible.

Here, in the case of the differential partition structure, it is preferable that the height of the first partition 212b of the first partition 212b or the second partition 212a is lower than the height of the second partition 212a. In addition, in the case of the channel type barrier rib structure or the groove type barrier rib structure, it is preferable that the channel is formed in the first barrier rib 212b or the groove is formed.

On the other hand, in the plasma display panel according to an embodiment of the present invention, although the red (R), green (G), and blue (B) discharge cells are shown and described as being arranged on the same line, they may be arranged in different shapes. It will be possible. For example, a delta type arrangement in which red (R), green (G) and blue (B) discharge cells are arranged in a triangular shape may be possible. In addition, the shape of the discharge cell may also be a variety of polygonal shapes, such as pentagonal, hexagonal, as well as rectangular.

Here, it is preferable that a predetermined discharge gas is filled in the discharge cells partitioned by the partition walls 212.

In addition, a phosphor layer 214 that emits visible light for image display may be formed in the discharge cells partitioned by the partition wall 212. For example, red (R), green (G), and blue (B) phosphor layers may be formed.

In addition to the red (R), green (G), and blue (B) phosphors, it is also possible to further form a white (W) and / or yellow (Y) phosphor layer.

In addition, the phosphor layers 214 of the red (R), green (G), and blue (B) discharge cells may have substantially the same thickness or may differ from one or more. For example, if the thickness of the phosphor layer 214 in at least one of the red (R), green (G), and blue (B) discharge cells is different from the other discharge cells, green (G) or blue (B) The thickness of the phosphor layer 214 in the discharge cell may be thicker than the thickness of the phosphor layer 214 in the red (R) discharge cell. Here, the thickness of the phosphor layer 214 in the green (G) discharge cell may be substantially the same as or different from the thickness of the phosphor layer 214 in the blue (B) discharge cell.

Meanwhile, in the above description of FIG. 2A, only the case where the first electrode 202 and the second electrode 203 are formed of one layer each is illustrated and described. However, the first electrode 202 or the second electrode is different from the above description. It is also possible that one or more of 203 consists of a plurality of layers. This will be described with reference to FIG. 2B.

Referring to FIG. 2B, the first electrode 202 and the second electrode 203 may be formed of a plurality of layers, for example, two layers.

In particular, in consideration of light transmittance and electrical conductivity, the first electrode 202 and the second electrode 203 are substantially made of silver (Ag) in order to emit light generated in the discharge cell to the outside and to secure driving efficiency. It is preferable to include bus electrodes 202b and 203b including an opaque material and transparent electrodes 202a and 203a including a transparent material such as transparent indium tin oxide (ITO).

As such, the reason for the first electrode 202 and the second electrode 203 to include the transparent electrodes 202a and 203a is that the visible light generated in the discharge cell is effectively emitted when emitted to the outside of the plasma display panel. To make it possible.

In addition, the reason why the first electrode 202 and the second electrode 203 include the bus electrodes 202b and 203b is that the first electrode 202 and the second electrode 203 are the transparent electrodes 202a and 203a. ), The driving efficiency can be reduced because the electrical conductivity of the transparent electrodes 202a and 203a is relatively low, so that the low electrical power of the transparent electrodes 202a and 203a can cause such a reduction in the driving efficiency. To compensate for conductivity.

As described above, when the first electrode 202 and the second electrode 203 include the bus electrodes 202b and 203b, the transparent electrodes 202a, It is preferable that a black layer (220, 221) is further provided between the 203a and the bus electrodes 202b and 203b.

Meanwhile, the transparent electrodes 202a and 203a may be omitted in the same structure as in FIG. 2B. For example, the first electrode 202 and the second electrode 203 may be formed of only the bus electrodes 202b and 203b without the transparent electrodes 202a and 203a in FIG. 2B. That is, the first electrode 202 and the second electrode 203 are ITO-Less electrodes made of one layer of the bus electrodes 202b and 203b.

In the meantime, only one example of the plasma display panel included in the plasma display apparatus according to the exemplary embodiment of the present invention is illustrated and described, and the present invention is not limited to the plasma display panel having the above-described structure. For example, the description hereinabove illustrates only the case where the top dielectric layer at number 204 and the bottom dielectric layer at number 215 are each one layer, but one or more of these top dielectric layers and bottom dielectric layers are a plurality of layers. It can also be layered.

In addition, a black layer (not shown) may be further formed on the partition 212 to prevent reflection of the external light due to the partition 212.

In addition, a black layer (not shown) may be further formed at a specific position on the front substrate 201 corresponding to the partition 212.

In addition, the width or thickness of the third electrode 213 formed on the rear substrate 211 may be substantially constant, but the width or thickness inside the discharge cell may be different from the width or thickness outside the discharge cell. will be. For example, the width or thickness inside the discharge cell may be wider or thicker than that outside the discharge cell.

As such, the structure of the plasma display panel which may be included in the plasma display apparatus according to the exemplary embodiment may be variously changed.

Next, FIG. 3 is a diagram for describing a frame for implementing gray levels of an image in a plasma display device according to an embodiment of the present invention.

4 is a view for explaining an example of the operation of the plasma display device according to an embodiment of the present invention.

First, referring to FIG. 3, a frame for realizing gray levels of an image in a plasma display device according to an exemplary embodiment of the present invention is divided into several subfields having different emission counts.

Although not illustrated, one or more subfields among the plurality of subfields may be grayed out according to a reset period for initializing all discharge cells, an address period for selecting discharge cells to be discharged, and the number of discharges. It can be divided into the sustain period (Sustain Period) to implement.

For example, when the image is to be displayed in 256 gray scales, one frame is divided into eight subfields SF1 to SF8 as shown in FIG. 3, and each of the eight subfields SF1 to SF8 is represented. The reset period, the address period and the sustain period are further divided.

The gray scale weight of the corresponding subfield may be set by adjusting the number of the sustain signals supplied in the sustain period. That is, a predetermined gray scale weight can be given to each subfield using the sustain period. For example, the gray scale weight of each subfield is 2 ⁿ by setting the gray scale weight of the first subfield to 2 ⁰ and the gray scale weight of the second subfield to 2 ¹ (where n = 0, 1). , 2, 3, 4, 5, 6, and 7) to increase the gray scale weight of each subfield. As described above, the number of sustain signals supplied in the sustain period of each subfield is adjusted according to the gray scale weight in each subfield, thereby implementing gray levels of various images.

The plasma display apparatus according to an embodiment of the present invention uses a plurality of frames to implement an image, for example, to display an image of 1 second. For example, 60 frames are used to display an image of 1 second. In this case, the length of one frame may be 1/60 second, that is, 16.67 ms. The length of such a frame may vary.

In FIG. 3, only one frame is composed of eight subfields. However, the number of subfields forming one frame may be variously changed. For example, one frame may be configured with 12 subfields from the first subfield to the twelfth subfield, or one frame may be configured with 10 subfields.

Also, in FIG. 3, subfields are arranged according to the order of increasing the magnitude of gray scale weight in one frame. Alternatively, subfields may be arranged in the order of decreasing gray scale weight in one frame. Subfields may be arranged regardless of the weight.

Next, referring to FIG. 4, an example of an operation of the plasma display apparatus according to an exemplary embodiment of the present invention in any one of a plurality of subfields included in the same frame as in FIG. 3 is shown.

First, the first ramp-down signal may be supplied to the first electrode Y by the driver 110 of FIG. 1 in the pre-reset period before the reset period. It will be appreciated that the various signals to be described later are supplied to the first electrode, the second electrode, or the third electrode by the driver 110 of FIG. 1.

In addition, while the first falling ramp signal is supplied to the first electrode Y, a pre-sustain signal in a polarity opposite to the first falling ramp signal may be supplied to the second electrode Z.

Here, it is preferable that the first falling ramp signal supplied to the first electrode Y gradually descends to the tenth voltage V10.

In addition, it is preferable that the pre-sustain signal maintain the pre-sustain voltage Vpz substantially constant. Here, it is preferable that the pre-sustain voltage Vpz is approximately the same voltage as the voltage of the sustain signal SUS supplied in the subsequent sustain period, that is, the sustain voltage Vs.

As such, when the first falling ramp signal is supplied to the first electrode Y and the presuspension signal is supplied to the second electrode Z in the pre-reset period, a wall of a predetermined polarity is formed on the first electrode Y. Wall charges are accumulated, and wall charges of opposite polarity to the first electrode Y are accumulated on the second electrode Z. For example, positive wall charges are accumulated on the first electrode Y, and negative wall charges are accumulated on the second electrode Z.

This makes it possible to generate a set-up discharge of sufficient intensity in the subsequent reset period, which in turn makes it possible to perform the initialization sufficiently stably.

In addition, even when the voltage of the rising ramp signal Ramp-Up supplied to the first electrode Y becomes smaller in the reset period, it is possible to generate the setup discharge of sufficient intensity.

From the viewpoint of securing the driving time, the pre-reset period is included before the reset period in the subfield arranged in time among the subfields of the frame, or the pre-reset before the reset period in two or three subfields of the subfield of the frame. It is also possible to include a period.

Alternatively, this pre-reset period may be omitted in all subfields.

After the pre-reset period, in a set-up period of a reset period for initialization, a ramp-up signal in a direction opposite to that of the first falling ramp signal may be supplied to the first electrode Y.

Here, the rising ramp signal may include a first rising ramp signal gradually increasing with a first slope from the twentieth voltage V20 to the thirtieth voltage V30 and the second rising ramp signal from the thirtieth voltage V30 to the forty-th voltage V40. It may include a second rising ramp signal rising to the slope.

In this setup period, a weak dark discharge, that is, setup discharge, occurs in the discharge cell by the rising ramp signal. This setup discharge causes a certain amount of wall charges to accumulate in the discharge cell.

Here, it is preferable that the second slope of the second rising ramp signal is gentler than the first slope. As such, when the second slope is made gentler than the first slope, the voltage is increased relatively quickly until the setup discharge occurs, and the voltage is increased relatively slowly while the setup discharge occurs. The amount of light generated by the setup discharge can be reduced.

Accordingly, the contrast characteristic can be improved.

In a set-down period after the set-up period, a second ramp-down signal in a direction opposite to that of the ramp ramp signal may be supplied to the first electrode Y after the ramp ramp signal.

Here, it is preferable that the second falling ramp signal gradually decreases from the twentieth voltage V20 to the fifty voltage V50.

As a result, weak erase discharge, that is, set-down discharge, occurs in the discharge cell. By this set-down discharge, wall charges such that address discharge can be stably generated in the discharge cells remain uniformly.

5A to 5B are diagrams for explaining another form of the rising ramp signal or the second falling ramp signal.

First, referring to FIG. 5A, the rising ramp signal gradually increases from the thirtieth voltage V30 to the forty-th voltage V40 after rapidly rising to the thirtieth voltage V30.

As such, the rising ramp signal may rise gradually with different inclinations over two stages as shown in FIG. 4 above, and may also rise gradually in one stage as shown here in FIG. 5A. It is possible to change to.

Next, referring to FIG. 5B, the second falling ramp signal has a form in which the voltage gradually decreases from the thirtieth voltage V30.

As described above, the second falling ramp signal may be changed in various forms, such as a different point in time at which the voltage falls.

Meanwhile, in the address period after the reset period, a scan bias signal that substantially maintains a voltage higher than the 50 th voltage V50 of the second falling ramp signal may be supplied to the first electrode Y. FIG.

In addition, the scan signal Scan, which decreases from the scan bias signal by the scan voltage ΔVy, may be supplied to all of the first electrodes Y1 to Yn.

For example, the first scan signal Scan 1 is supplied to the first first electrode Y1 of the plurality of first electrodes Y, and then the second scan signal (2) is applied to the second first electrode Y2. Scan 2) is supplied, and the n-th scan signal Scan n is supplied to the n-th first electrode Yn.

On the other hand, the width of the scan signal in units of subfields may vary. That is, the width of the scan signal Scan in at least one subfield may be different from the width of the scan signal Scan in other subfields. For example, the width of the scan signal Scan in the subfield located later in time may be smaller than the width of the scan signal Scan in the subfield located earlier. In addition, the scan signal scan width decreases according to the arrangement order of the subfields gradually, such as 2.6 ms (microseconds), 2.3 ms (microseconds), 2.1 ms (microseconds), 1.9 ms (microseconds), and the like. Or 2.6 ㎲ (microseconds), 2.3 ㎲ (microseconds), 2.3 ㎲ (microseconds), 2.1 ㎲ (microseconds) ... 1.9 ㎲ (microseconds), 1.9 ㎲ (microseconds) It could be done.

As such, when the scan signal Scan is supplied to the first electrode Y, a data signal rising by the magnitude ΔVd of the data voltage may be supplied to the third electrode X to correspond to the scan signal.

As the scan signal Scan and the data signal Data are supplied, the voltage difference between the voltage of the scan signal and the data voltage Vd of the data signal and the wall voltage due to the wall charges generated in the reset period. In addition, address discharge is generated in the discharge cells to which the voltage Vd of the data signal is supplied.

Here, it is preferable that the sustain bias signal is supplied to the second electrode Z in order to prevent the address discharge from becoming unstable due to the interference of the second electrode Z in the address period.

Here, it is preferable that the sustain bias signal maintain a substantially constant sustain bias voltage Vz smaller than the voltage of the sustain signal supplied in the sustain period and larger than the voltage of the ground level GND.

Thereafter, the sustain signal SUS may be supplied to at least one of the first electrode Y and the second electrode Z in the sustain period for displaying an image. The sustain signal SUS preferably has a magnitude of a voltage of ΔVs.

When the sustain signal SUS is supplied, the discharge cell selected by the address discharge is added to the first electrode when the wall voltage in the discharge cell and the sustain voltage Vs of the sustain signal SUS are added and the sustain signal SUS is supplied. A sustain discharge, that is, a display discharge, occurs between (Y) and the second electrode Z.

In this sustain period, the sustain signal supplied to one or more of the first electrode Y or the second electrode Z may be changed in relation to the average power level. This is as follows.

Next, FIG. 6 is a diagram for explaining an average power level.

Referring to FIG. 6, the average power level is a method of adjusting the number of sustain signals in relation to the size of a portion where an image is displayed on the plasma display panel. That is, the average power level is determined according to the number of discharge cells that are turned on among the discharge cells of the plasma display panel.

Preferably, as the value of the average power level APL increases, the number of sustain signals per unit gray scale decreases, and as the value of the average power level APL decreases, the number of sustain signals per unit gray scale increases.

For example, when an image is displayed on a portion of a relatively small area on the screen of the plasma display panel 600 as shown in (a), that is, a discharge cell that is turned on among discharge cells formed in the plasma display panel 600. When the number of cells is relatively small (in this case, the APL level is relatively low), since the number of discharge cells contributing to the image display is relatively small, the sustain per unit gradation supplied to each discharge cell contributing to the image display is relatively small. Make the number of signals relatively large. Accordingly, the overall brightness of the image can be increased.

On the contrary, when an image is displayed on a portion of a relatively large area on the screen of the plasma display panel 600 as shown in (b), that is, the number of discharge cells turned on among the discharge cells formed in the plasma display panel 600 is relatively high. In many cases (in this case, the APL level is relatively high), since the number of discharge cells contributing to the image display is relatively large, the number of sustain signals per unit gradation supplied to each discharge cell contributing to the image display is determined. Relatively few. Accordingly, a sudden increase in the total power consumption of the plasma display panel 600 is prevented.

As an example, when the average power level is a level, in this case, the number of sustain signals per unit gradation is N.

In addition, when the average power level is a b level higher than the above-described a level, the number of sustain signals per unit gray level may be M less than N described above.

Next, FIGS. 7A to 7B are diagrams for explaining an example of a method of changing a sustain signal in relation to an average power level.

First, referring to FIG. 7A, when the average power level is the first level APL 1, as shown in (b), at least one of the first type and the second electrode may have a first type sustain signal. Supplied. On the other hand, in the case of the second level APL 2, the second type sustain signal is supplied to at least one of the first electrode and the second electrode as shown in (a).

Here, the length of the voltage rise period of the second type sustain signal as shown in (a) is preferably longer than the length of the voltage rise period of the first type sustain signal as shown in (b).

In addition, it is preferable that the length of the voltage drop period of the first type sustain signal as shown in (b) is shorter than the length of the voltage drop period of the second type sustain signal as shown in (a).

As such, the length of the voltage rising period of the sustain signal is relatively long at the second level where the average power level is relatively high, and the length of the voltage falling period of the sustain signal is relatively the first level having the relatively low average power level. If it is short, the amount of light generated by the sustain discharge increases. Accordingly, the luminance of the image to be implemented may increase. The reason for this will be described with reference to FIG. 7B.

Next, referring to FIG. 7B, when the length of the voltage rising period of the sustain signal is relatively long at the second level where the average power level is relatively high, in the voltage rising period of the sustain signal supplied to at least one of the first electrode and the second electrode, FIG. The voltage rises to the first voltage V1, the voltage falls from the first voltage V1 to the second voltage V2 lower than the first voltage V1, and the second voltage V2 to the first voltage V1. It may rise to a higher third voltage V3.

This can be caused by securing a time for the wall charge to be sufficiently accumulated in the discharge cell when the voltage rise period is relatively long.

More specifically, when the length of the voltage rise period is sufficiently long, when the first voltage V1 is reached while the voltage of the first electrode or the second electrode is increased, the wall charges are sufficiently accumulated in the discharge cell, thereby primarily discharging. This can happen. As a result, the amount of wall charges in the discharge cell is instantaneously reduced by the discharge, so that the voltage of the first electrode or the second electrode can drop from the first voltage V1 to the second voltage V2.

Subsequently, if the voltage of the first electrode or the second electrode is continuously increased, the wall charges are accumulated in the discharge cells, so that the voltage of the first electrode or the second electrode is changed from the second voltage V2 to the third voltage ( Up to V3). As described above, discharge may occur in the process of increasing the voltage of the first electrode or the second electrode from the second voltage V2 to the third voltage V3.

That is, double discharge may occur.

Such double discharges generate more light than conventional single discharges, and thus brightness of an image may be increased.

In addition, in the second level where the average power level is relatively high, the number of sustain signals per unit gradation is set relatively small as described above in detail with reference to FIG. 6, even when the length of the voltage rise period of the sustain signal is sufficiently long. It can be independent of the increase in time.

On the other hand, if the length of the voltage drop period of the sustain signal is relatively short at the first level where the average power level is relatively low, relatively strong discharge is generated by increasing the voltage change rate per hour (dv / dt) in the voltage drop period. Accordingly, the luminance of the image may be increased by increasing the amount of light generated.

In addition, in the first level where the average power level is relatively low, since the number of sustain signals per unit gray level is set to be relatively large as described above with reference to FIG. However, as in the present invention, if the length of the voltage drop period of the sustain signal is relatively short, the shortage of the driving time can be sufficiently compensated.

Next, FIGS. 8A to 8B are diagrams for explaining the mode of discharge at the first level or the second level.

First, referring to FIG. 8A, an example of a form of discharge in a second type sustain signal at a second level having a relatively high average power level is shown.

For example, in the second type sustain signal, the voltage difference between the first electrode and the second electrode increases in the voltage rise period of the sustain signal supplied to the first electrode, and the sustain signal supplied to the first electrode is increased. In the voltage rise period, the voltage difference between the first electrode and the second electrode increases.

As a result, sustain discharge occurs in the voltage rise period of the sustain signal supplied to the first electrode, and sustain discharge occurs in the voltage rise period of the sustain signal supplied to the second electrode.

As such, the reason for increasing the voltage difference between the first electrode and the second electrode in the voltage rising period of the sustain signal is that the voltage rising period of the sustain signal is increased at the second level where the average power level is relatively high as shown in FIG. 7B. This is because the luminance of the image can be improved by making the length sufficiently long. As a result, when the average power level is a relatively high second level, it is advantageous to increase the luminance to generate sustain discharge in the voltage rise period of the sustain signal.

Next, referring to FIG. 8B, an example of the type of discharge in the first type sustain signal at the first level at which the average power level is relatively low is shown.

For example, in the first type sustain signal, a voltage difference between the first electrode and the second electrode may increase in the voltage drop period of the sustain signal supplied to the first electrode as shown in (a). More specifically, during the voltage rising period d1 of the sustain signal supplied to the second electrode, the voltage difference between the first electrode and the second electrode rather decreases, and the voltage drop period d2 of the sustain signal supplied to the first electrode. ), The voltage difference between the first electrode and the second electrode increases.

Alternatively, as shown in (b), a voltage difference between the first electrode and the second electrode may increase in the voltage drop period of the sustain signal supplied to the second electrode. More specifically, during the voltage rising period d1 of the sustain signal supplied to the first electrode, the voltage difference between the first electrode and the second electrode rather decreases, and the voltage drop period d2 of the sustain signal supplied to the second electrode. ), The voltage difference between the first electrode and the second electrode increases.

Accordingly, sustain discharge may occur in a voltage drop period of the sustain signal supplied to at least one of the first electrode and the second electrode.

As such, the reason for increasing the voltage difference between the first electrode and the second electrode in the voltage drop period of the sustain signal is as described above in detail with reference to FIGS. 7A to 7B. This is because a strong sustain discharge can be generated by shortening the length of the voltage lowering period of the film sufficiently, thereby improving the brightness of the image. As a result, when the average power level is a relatively low first level, it is advantageous to increase the luminance to generate sustain discharge in the voltage drop period of the sustain signal.

Next, FIG. 9 is a figure for demonstrating an example of the structure of the drive part for supplying a sustain signal.

Referring to FIG. 9, the driving unit of the plasma display device according to the embodiment may include an energy recovery circuit.

The energy recovery circuit includes a voltage storage unit 900, a storage voltage supply unit 901, a voltage recovery unit 902, a sustain voltage supply unit 904, a base voltage supply unit 905, and a first inductor unit. 903 and the second inductor portion 906 are preferably included.

The voltage storage unit 900 includes a voltage storage capacitor unit C, and stores the voltage using the energy storage capacitor unit C.

The storage voltage supply unit 901 includes a storage voltage supply control switch unit S1, and the voltage stored in the voltage storage unit 900 is stored in the first electrode of the plasma display panel using the storage voltage supply control switch unit S1. Or to a second electrode.

The voltage recovery unit 902 includes a voltage recovery control switch unit S2, and the reactive energy of the first electrode or the second electrode of the plasma display panel is converted into a voltage storage unit using the voltage recovery control switch unit S2. 900) to be recovered and stored.

The first inductor 903 includes a first resonance inductor L1, and the voltage stored in the voltage storage unit 900 is transferred to the first electrode or the second electrode using the first resonance inductor L1. Generate an LC resonance to be supplied.

The second inductor unit 906 includes a second resonance inductor L2, and the voltage is recovered from the first electrode or the second electrode to the voltage storage unit 900 by using the second resonance inductor L2. Generates LC resonance when

The sustain voltage supply unit 904 includes a sustain voltage supply control switch unit S3, and the sustain voltage source Vs generated by the sustain voltage source using the sustain voltage supply control switch unit S3 is the first electrode or the second electrode. To be supplied to the electrode.

The base voltage supply unit 905 includes a base voltage supply control switch unit S4, and the base voltage GND generated by the base voltage source using the base voltage supply control switch unit S4 is the first electrode or the second electrode. To be supplied to the electrode. That is, the first electrode or the second electrode is grounded.

The operation of the driving unit of FIG. 9 will be described with reference to FIG. 10.

10 is a view for explaining an example of the operation of the driving unit of FIG.

Referring to FIG. 10, first, the voltage recovery unit 902, the sustain voltage supply unit 904, and the base voltage supply unit 905 are turned off in the voltage rising period, and the storage voltage supply unit 901 is turned on. ) do.

Then, an energy supply path is formed through the voltage storage unit 900, the first node n1, the storage voltage supply unit 901, the first inductor unit 903, and the second node n2. Accordingly, the voltage stored in the voltage storage unit 900 is supplied to the first electrode or the second electrode through LC resonance by the first resonance inductor L1 of the first inductor unit 903.

Here, assuming that the voltage storage unit 900 stores a sustain voltage of 0.5 times, that is, a voltage of 1/2 Vs, the voltage of the first electrode or the second electrode rises up to the maximum sustain voltage Vs in the voltage rising period. can do.

Here, in the second level where the average power level is relatively high, the time for the storage voltage supply unit 901 to remain in the on state can be relatively long to sufficiently lengthen the length of the voltage rise period described above.

On the other hand, at the first level where the average power level is relatively low, the time for which the storage voltage supply unit 901 is kept in the on state can be shortened in order to shorten the length of the voltage rise period relatively.

On the other hand, the inductance value of the first inductor unit 903 is set sufficiently large in order to sufficiently lengthen the length of the voltage rise period at the second level where the average power level is relatively high and at the same time to generate the double discharge more easily. desirable. For example, the inductance value of the first inductor unit 903 may be set to about 0.2 μH (micro Henry) or more and 0.3 μH (micro Henry) or less.

Next, in the voltage sustain period, the sustain voltage supply control switch section S3 of the sustain voltage supply section 904 is turned on. Then, the sustain voltage Vs generated by the sustain voltage source is supplied to the first electrode or the second electrode via the second node n2.

Thus, the first electrode or the second electrode maintains the sustain voltage Vs substantially constant.

Next, in the voltage drop period, the voltage recovery unit 902 is performed with both the sustain voltage supply control switch unit S3 of the sustain voltage supply unit 904 and the storage voltage supply control switch unit S1 of the storage voltage supply unit 901 turned off. Voltage recovery control switch unit (S2) is turned on.

Then, energy recovery via the first electrode or the second electrode, the second node n2, the second inductor unit 906, the voltage recovery unit 902, the first node n1, and the voltage storage unit 900 is performed. A path is formed. Then, the voltage of the first electrode or the second electrode is recovered and stored in the voltage storage unit 900 through LC resonance by the second inductor unit 906.

As a result, the voltage of the first electrode or the second electrode may drop from the sustain voltage Vs to the lowest base voltage GND.

Here, in the first level where the average power level is relatively low, the time for maintaining the on state of the voltage recovery unit 902 may be relatively short to sufficiently shorten the length of the voltage drop period described above.

On the other hand, in the second level where the average power level is relatively high, the time for maintaining the on state of the voltage recovery unit 902 may be relatively long to relatively lengthen the length of the voltage drop period.

In addition, the inductance value of the second inductor unit 906 is larger than the inductance value of the first inductor unit 903 in order to increase the energy recovery efficiency during the voltage drop period at the second level where the average power level is relatively high. can do. Preferably, the inductance value of the second inductor unit 906 may be set to about two times or more and three times or less the inductance value of the first inductor unit 903.

For example, the inductance value from the second inductor 906 may be set to about 0.4 μH (micro henry) or more and about 0.9 μH (micro henry) or less.

Meanwhile, the base voltage supply control switch S4 of the base voltage supply unit 905 may be turned on in periods other than the voltage rising period, the voltage holding period, and the voltage falling period. Then, the first electrode or the second electrode can maintain the ground voltage GND.

By the above-described method, the driver may supply the first type sustain signal or the second type sustain signal to the first electrode or the second electrode.

Next, FIG. 11 is a figure for demonstrating another example of the structure of a drive part.

Referring to FIG. 11, the first inductor unit 1100 is commonly disposed in an energy supply path and an energy recovery path. On the other hand, the second inductor 1110 is disposed only in the energy recovery path.

Here, even when the inductance value of the first inductor unit 1100 is equal to or greater than the inductance value of the second inductor unit 1110, the total inductance value on the energy recovery path may be kept larger than the total inductance value on the energy supply path. Can be.

Accordingly, the same effects as in the case of FIG. 10 can be obtained.

As such, the technical configuration of the present invention described above can be understood by those skilled in the art that the present invention can be implemented in other specific forms without changing the technical spirit or essential features of the present invention.

Therefore, the exemplary embodiments described above are to be understood as illustrative and not restrictive in all respects, and the scope of the present invention is indicated by the appended claims rather than the foregoing detailed description, and the meaning and scope of the claims are as follows. And all changes or modifications derived from the equivalent concept should be interpreted as being included in the scope of the present invention.

As described in detail above, the plasma display apparatus of the present invention has an effect of increasing the luminance of an image implemented by changing the sustain signal in relation to the average power level.

Claims (6)

A plasma display panel having a first electrode and a second electrode parallel to each other; One or more of the first electrode and the second electrode when the sustain signal is supplied to at least one of the first electrode or the second electrode in the sustain period for displaying an image, and the average power level is the first level. When the first type sustain signal is supplied and the average power level is a second level higher than the first level, a second type sustain signal different from the first type sustain signal is output from the first electrode or the second electrode. Drive part to supply more than one Including, The sustain signal includes a voltage rising period, a voltage sustain period, and a voltage falling period, and the length of the voltage rising period of the second type sustain signal is longer than the length of the voltage rising period of the first type sustain signal, And the length of the voltage drop period of the first type sustain signal is shorter than the length of the voltage drop period of the second type sustain signal. The method of claim 1, And the voltage difference between the first electrode and the second electrode increases in the voltage rising period of the sustain signal supplied to at least one of the first electrode and the second electrode in the second type sustain signal. The method of claim 1, And the voltage difference between the first electrode and the second electrode increases in the voltage drop period of the sustain signal supplied to at least one of the first electrode and the second electrode in the first type sustain signal. The method of claim 1, In the second type sustain signal, a voltage rises to a first voltage in a voltage rising period of a sustain signal supplied to at least one of the first electrode and the second electrode, and thereafter, a second voltage lower than the first voltage from the first voltage. And descends to and then rises from the second voltage to a third voltage higher than the first voltage. The method of claim 1, The driving unit The sustain signal is supplied to at least one of the first electrode and the second electrode by using an energy recovery circuit including an energy supply path including a first inductor and an energy recovery path including a second inductor. And an inductance value of the second inductor unit is greater than an inductance value of the first inductor unit. The method of claim 5, And an inductance value of the second inductor portion is two or more times and three times or less than the inductance value of the first inductor portion.

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