KR20040075484A - Apparatus to control driving power automatically for plasma display panel and the method thereof - Google Patents

Abstract

PURPOSE: An automatic power control apparatus and a method of a plasma display panel are provided to increase brightness in a bright room by setting the number of maintenance discharge pulses with respect to the bright room having a relative low brightness greater than that of a dark room. CONSTITUTION: An average signal level detector(320) measures a load rate of an image signal inputted from an outside. A memory(340) divides a consumption power control stage according to the load rate, determines a maximum value and a minimum value of a pulse generation stage according to the consumption power control stage, and stores information related to the number of maintenance discharge pulses determined according to the pulse generation stage. A power controller(330) outputs the information with reference to the memory, depending on an intensity of light in external environment where a panel is placed.

Description

Automatic power control device for plasma display panel and its control method {APPARATUS TO CONTROL DRIVING POWER AUTOMATICALLY FOR PLASMA DISPLAY PANEL AND THE METHOD THEREOF}

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a plasma display panel, and more particularly, to an automatic power control apparatus for a display panel and a method of controlling the same, which adjust brightness of the panel according to a change in load factor.

In general, since plasma display panels have high power consumption due to their driving characteristics, an apparatus for controlling power consumption according to the load ratio of a frame to be displayed is required. As a method of controlling such power consumption, a method of limiting power consumption by using auto power control has been used.

1 is a graph showing power consumption according to a load ratio.

As shown in FIG. 1, the automatic power control method controls power so that the panel operates in the stable operating area SOA. In the stable operating region, when the power consumption is 500W, the lower boundary has a load ratio (L / R) of 15%, and the upper boundary has a load ratio of about 20-30%.

However, if the power consumption is kept at the upper limit, the panel driver cannot operate stably, so the power consumption is gradually reduced from the upper limit to the lower limit so that the human eye cannot recognize it.

On the other hand, even if the panel exhibits the same power consumption (ie, the same brightness), the relative brightness perceived by the user varies depending on the environment in which the panel operates. That is, the relative luminance is perceived to be lower when operating in a bright room than when operating in a dark room. However, the conventional automatic power control method does not take into consideration the environment of use of the panel, so that when the panel operates in a bright room, the relative luminance is low, so that the screen is hard to see.

Therefore, the present invention is to solve the problems of the prior art, a plasma display panel for measuring the brightness of the light of the environment in which the panel operating by using a photoconductive device and thereby adjust the brightness by varying the number of sustain discharge pulses An object of the present invention is to provide an automatic power control apparatus and a control method thereof.

1 is a graph showing power consumption according to a load ratio.

2 is a diagram illustrating a configuration of a plasma display panel according to an exemplary embodiment of the present invention.

3 is a diagram illustrating a configuration of a controller of a plasma display panel according to an exemplary embodiment of the present invention.

4 is a diagram illustrating a configuration of a photoconductive device unit of a control unit according to an exemplary embodiment of the present invention.

5 is a view showing an automatic power control lookup table of the dark room according to an embodiment of the present invention.

6 is a view showing a table for automatic power control look-up of the clear room according to an embodiment of the present invention.

*** Description of the symbols for the main parts of the drawings ***

100: panel 200: address data generator

300: control unit 400: sustain discharge pulse generating unit

310: image data processing unit 320: average voltage level detection unit

330: power control unit 340: memory

331: photoconductive element unit 332: voltage determination unit

333: automatic power control calculation unit

An automatic power control apparatus for a plasma display panel according to an aspect of the present invention for achieving the above technical problem is the automatic power of the plasma display panel including a plurality of address electrodes and a plurality of scan electrodes and sustain electrodes arranged in pairs with each other. As a control device,

An average signal level detector for measuring a load ratio of an image signal input from the outside; A memory for classifying a predetermined number of power consumption control steps according to the load ratio, determining an upper limit value and a lower limit value of a pulse generation step according to the power consumption control step, and storing information on the number of sustain discharge pulses determined according to the pulse generation step; And outputting information about the number of sustain discharge pulses according to a current load ratio, wherein the power control unit outputs information about the number of sustain discharge pulses by referring to the memory according to the light intensity of an external environment in which the panel is located.

The power control unit,

A photoconductive device unit for measuring the intensity of light in the external environment; A voltage determination unit for dividing the intensity of light measured by the photoconductive element into a predetermined number of contrast steps; And an automatic power control calculation unit for outputting information on the number of sustain discharge pulses corresponding to a current load ratio by referring to the memory according to the contrast level divided by the voltage determination unit.

At this time, the photoconductive element portion,

A photoconductive device having a variable resistance value due to light and a resistor are connected in series. The voltage of the contact point between the resistor and the photoconductive device is measured and transmitted to the voltage determination unit.

At this time, in the memory,

The lower limit value of the sustain discharge pulse generating step is stored differently according to the contrast level,

According to the contrast step, the number of sustain discharge pulses according to the sustain discharge pulse generation steps is stored differently.

In addition, the power control unit,

According to the contrast step, the number of sustain discharge pulses corresponding to the current load ratio is output through a predetermined calculation process based on the information stored in the memory.

In addition, the plasma display panel according to an aspect of the present invention,

A plasma display panel including a plurality of address electrodes, a plurality of scan electrodes and a sustain electrode arranged in pairs with each other; It corrects and outputs the external video signal, and measures the intensity of the external light to distinguish whether the external environment is dark room or bright room, and divides all load change rate into a certain number, and maintains discharge of the dark room / bright room and each load rate. A control unit for determining the number of pulses differently and storing them in a table, and determining which step the load ratio of the currently input image signal belongs to and outputting information on the number of sustain discharge pulses corresponding to the load ratio of current data according to the load ratio; An address data generator for generating address data corresponding to the correction data output from the controller and applying the address data to an address electrode of the plasma display panel; And a sustain discharge pulse generator for generating sustain discharge pulses corresponding to the sustain discharge information from the controller and applying the sustain discharge pulses to the sustain electrodes and the scan electrodes.

The control unit,

An average signal level detector for measuring a load ratio of an image signal input from the outside; A memory for classifying a predetermined number of power consumption control steps according to the load ratio, determining an upper limit value and a lower limit value of a pulse generation step according to the power consumption control step, and storing information on the number of sustain discharge pulses determined according to the pulse generation step; And outputting information about the number of sustain discharge pulses according to a current load ratio, wherein the power control unit outputs information about the number of sustain discharge pulses by referring to the memory according to the light intensity of an external environment in which the panel is located.

In addition, the automatic power consumption control method of the plasma display panel according to another aspect of the present invention automatically controls the power consumption of the plasma display panel including a plurality of address electrodes, a plurality of scan electrodes and sustain electrodes arranged in pairs with each other As a way to,

Classifying all load ratios into a predetermined number of automatic power control steps, determining an upper limit value and a lower limit value of the pulse generating step of each divided part, and determining and storing the number of generating discharge pulses according to the pulse generating step in a table. Stage 1; A second step of dividing the external environment into a predetermined number of contrast steps by measuring the light intensity of the external environment of the plasma display panel; And a third step of calculating a load ratio of the currently input data, determining the number of sustain discharge pulses generated according to the calculated load ratio and the contrast level division result, and outputting information on the number of sustain discharge pulses.

The first step,

The lower limit value of the sustain discharge pulse generation step is determined differently according to the contrast level,

According to the contrast step, the number of sustain discharge pulses according to each sustain discharge pulse generation step is determined differently,

The second step,

The light and dark stages are distinguished through a photoconductive device whose resistance is changed by light,

The third step,

The information on the number of sustain discharge pulses corresponding to the current load factor is output through a predetermined calculation process based on the contrast information and the table information stored in the first step.

Hereinafter, the present invention will be described in detail with reference to the accompanying drawings the most preferred embodiment that can be easily carried out by those of ordinary skill in the art as follows.

2 is a diagram illustrating a configuration of a plasma display panel according to an exemplary embodiment of the present invention.

As shown in FIG. 2, the plasma display panel according to an exemplary embodiment of the present invention includes a panel 100, a controller 300, an address data generator 200, and a sustain discharge pulse generator 400.

The panel 100 includes a plurality of address electrodes and a plurality of scan electrodes and sustain electrodes paired with each other and arranged in zigzag. The controller 300 corrects and outputs an external video signal, calculates a load ratio of the currently input video signal, and outputs sustain discharge pulse information corresponding to the calculated load change rate.

The address data generator 200 generates address data corresponding to the correction data output from the controller 300 and applies the address data to the address electrodes of the panel 100. The sustain discharge pulse generator 400 generates sustain pulses and scan pulses corresponding to the sustain discharge information from the controller 300 and applies them to the sustain electrodes and the scan electrodes, respectively.

3 illustrates an internal configuration of the controller 300 of FIG. 2.

As shown in FIG. 3, the controller 300 includes an image data processor 310, an average signal level detector 320, a power controller 330, and a memory 340.

The image data processor 310 corrects and outputs an image signal. The memory 340 divides the load rate into a certain number, and divides the automatic power consumption control step according to the load rate to determine the upper limit value and the lower limit value of the number of sustain discharge pulses in each step (hereinafter, APC LUT (auto power control look up table) )).

The average signal level detector 320 measures the load ratio of the image signal input from the outside.

The power controller 330 determines an upper limit value and a lower limit value of the number of sustain discharge pulses according to the load ratio of the currently input data with reference to the APC LUT of the memory 340, and determines the sustain discharge pulse information 400 based on the determined sustain discharge pulse information. Will output

The power control unit 330 includes a photoconductive device unit 331, a voltage determination unit 332, and an automatic power control calculator 333.

4 illustrates the configuration of the photoconductive element unit 331.

As shown in FIG. 4, the photoconductive element unit 331 connects the resistor R and the photoconductive element CdS in series, and measures the voltage of the contact point of the resistor R and the photoconductive element CdS. do. The photoconductive element CdS is a device whose resistance value is changed by light, and the stronger the light from outside, the smaller the resistance value.

The voltage determining unit 332 determines whether the external environment is a dark room or a bright room through the resistance value transmitted from the photoconductive device unit 331.

The automatic power control calculation unit 333 reads the APC LUTs applied to the bright room and the dark room from the memory 340 according to the determination of the voltage determination unit 332, and applies the load rate transferred from the average signal level detection unit 320. Accordingly, the number of sustain discharge pulses is transmitted to the sustain discharge pulse generator 400.

Figure 5 shows an example of a typical APC LUT applied in the darkroom according to an embodiment of the present invention.

As shown in FIG. 5, the APC LUT divides the APC step according to the load ratio, and stores the upper limit value and the lower limit value of the sustain discharge pulse generation step determined in each step. For example, when the APC stage according to the load ratio is 8, the upper limit UPPER of the sustain discharge pulse generation step is 00 (hexadecimal) and the lower limit value LOWER is 07 (hexadecimal). However, the number of sustain discharge pulses in the stage of sustain discharge pulse generation 00 (0 decimal) is 04D1 (hexadecimal, 1233 decimal), and the number of sustain discharge pulses in the stage of sustain discharge pulse 07 (decimal 7) 04B4 (hexadecimal, decimal 1204). ) Therefore, the number of sustain discharge pulses gradually decreases from 1233 to 1204.

On the other hand, if it is determined that the external environment is clear, the lower limit of the number of sustain discharge pulses should be set higher than that of the dark room to increase the relative brightness felt by the user.

6 is a diagram illustrating an APC LUT applied in a bright room according to a first embodiment of the present invention.

As shown in FIG. 6, in the conventional general APC LUT shown in FIG. 5, the number of sustain discharge pulses according to the sustain discharge pulse generation step is maintained as it is, and the lower limit LOWER of the sustain discharge pulse generation step is lower than that of the dark room. Lowered. That is, when the APC stage according to the load ratio is 8, the upper limit UPPER of the sustain discharge pulse generation step in the dark room is 00 (hexadecimal) and the lower limit value LOWER is 07 (hexadecimal). By the way, according to the first embodiment of the present invention, by lowering the lower limit value of the sustain discharge pulse generating step to 00, the number of sustain discharge pulses is kept at 04D1 (hexadecimal, 1233 decimal) to increase the brightness.

On the other hand, as a method of improving the brightness of the bright room according to the second embodiment of the present invention, the lower limit value LOWER of the sustain discharge pulse generation step is set equal to that of the dark room, and the number of sustain discharge pulses according to each sustain discharge pulse generation step is increased. It is also possible to increase the luminance.

In addition, the APC LUT applied in the dark room and the dark room may be separately stored in the memory 340, and only the APC LUT applied to the dark room is stored in the memory 340, and APC LUT applied to the dark room through a predetermined calculation step. You can also get the APC LUT that applies to your room.

Next, an automatic power control method using the control device for the automatic power of the plasma display panel according to the embodiment of the present invention having such a configuration will be described in detail.

First, a video signal including a data component (R, G, B) and a synchronization signal is input from the outside. Then, the image data processor 310 corrects the data components R, G, and B to implement the same luminance level. The average signal level detector 320 measures the average signal level of the data components R, G, and B. The measured average signal level is input to the power controller 330.

The voltage determining unit 332 of the power control unit 330 determines whether the external environment is a bright room or a dark room through the voltage transmitted from the photoconductive device unit 331. Then, the APC calculator 333 determines which section of the load ratio of the load factor of the APC LUT stored in the memory 340 is the load rate currently measured by the average signal level detector 320. In this case, when the external environment is a dark room, the conventional APC LUT is applied, and in the dark room, the modified APC LUT is applied as described above. In this way, the sustain discharge information corresponding to the external environment (dark room or bright room) and the current load ratio is output to the sustain discharge pulse generator 400.

Then, the sustain scan pulse generator 400 receives sustain discharge information, generates sustain pulses and scan pulses according to the number of sustain discharge pulses, and applies them to the sustain electrodes and the scan electrodes.

The address data generator 200 also generates address data corresponding to the correction data output from the image data processor 310 and applies the address data to the address electrode lines. Then, image data is displayed on the panel 100.

Thus, by setting the lower limit of the number of sustain discharge pulses differently according to the external environment (dark room or bright room), the relative luminance in the bright room and the dark room can be made the same.

In the above, the external environment is divided into a dark room and a bright room for convenience, but the bright room may be divided into several stages according to the light intensity, and the lower limit of the number of sustain discharge pulses may be set differently according to each stage.

The drawings and detailed description of the invention are merely exemplary of the invention, which are used for the purpose of illustrating the invention only and are not intended to limit the scope of the invention as defined in the appended claims or claims. Therefore, those skilled in the art will understand that various modifications and equivalent other embodiments are possible from this. Therefore, the true technical protection scope of the present invention will be defined by the technical spirit of the appended claims.

As described above, according to the present invention, it is possible to increase the luminance in the bright room by determining whether the external environment is a dark room or a bright room using a photoconductive element, and setting the number of sustain discharge pulses in the bright room having a relatively low luminance higher than the dark room. have.

Claims (13)

An automatic power control apparatus for a plasma display panel including a plurality of address electrodes and a plurality of scan electrodes and sustain electrodes paired with one another in pairs, An average signal level detector for measuring a load ratio of an image signal input from the outside; A memory for classifying a predetermined number of power consumption control steps according to the load ratio, determining an upper limit value and a lower limit value of a pulse generation step according to the power consumption control step, and storing information on the number of sustain discharge pulses determined according to the pulse generation step; And The power control unit outputs the number of sustain discharge pulses according to the current load ratio, and outputs the number of sustain discharge pulses with reference to the memory according to the light intensity of the external environment where the panel is located. Automatic power control device of the plasma display panel comprising a. The method of claim 1, The power control unit, A photoconductive device unit for measuring the intensity of light in the external environment; A voltage determination unit for dividing the intensity of light measured by the photoconductive element into a predetermined number of contrast steps; And An automatic power control calculator for outputting information on the number of sustain discharge pulses corresponding to a current load factor by referring to the memory according to the contrast level separated by the voltage determination unit Automatic power control device of the plasma display panel comprising a. The method of claim 2, The photoconductive element portion, The photoconductive device having a variable resistance value due to light and a resistor are connected in series, and the voltage of the contact point between the resistor and the photoconductive device is measured and transmitted to the voltage determination unit. Automatic power control device of plasma display panel. The method of claim 2, The memory, And a lower limit value of the sustain discharge pulse generation step according to the contrast level. The method of claim 2, The memory, And an automatic power control device for the plasma display panel in which the number of sustain discharge pulses according to each sustain discharge pulse generation step is stored differently according to the contrast stage. The method of claim 2, The power control unit, Outputting information on the number of sustain discharge pulses corresponding to the current load ratio through a predetermined calculation process based on the information stored in the memory according to the contrast level; Automatic power control device of plasma display panel. A plasma display panel including a plurality of address electrodes, a plurality of scan electrodes and a sustain electrode arranged in pairs with each other; It corrects and outputs the external video signal, and measures the intensity of the external light to distinguish whether the external environment is dark room or bright room, and divides all load change rate into a certain number, and maintains discharge of the dark room / bright room and each load rate. A control unit for determining the number of pulses differently and storing them in a table, and determining which step the load ratio of the currently input image signal belongs to and outputting information on the number of sustain discharge pulses corresponding to the load ratio of current data according to the load ratio; An address data generator for generating address data corresponding to the correction data output from the controller and applying the address data to an address electrode of the plasma display panel; And A sustain discharge pulse generator for generating sustain discharge pulses corresponding to the sustain discharge information from the controller and applying the sustain discharge pulses to the sustain electrodes and the scan electrodes; Plasma display panel comprising a. The method of claim 7, wherein The control unit, An average signal level detector for measuring a load ratio of an image signal input from the outside; A memory for classifying a predetermined number of power consumption control steps according to the load ratio, determining an upper limit value and a lower limit value of a pulse generation step according to the power consumption control step, and storing information on the number of sustain discharge pulses determined according to the pulse generation step; And The power control unit outputs the number of sustain discharge pulses according to the current load ratio, and outputs the number of sustain discharge pulses with reference to the memory according to the light intensity of the external environment where the panel is located. Plasma display panel comprising a. A method of automatically controlling power consumption of a plasma display panel including a plurality of address electrodes, a plurality of scan electrodes and a sustain electrode arranged in pairs with each other, Classifying all load ratios into a predetermined number of automatic power control steps, determining an upper limit value and a lower limit value of the pulse generating step of each divided part, and determining and storing the number of generating discharge pulses according to the pulse generating step in a table. Stage 1; A second step of dividing the external environment into a predetermined number of contrast steps by measuring the light intensity of the external environment of the plasma display panel; And A third step of calculating a load ratio of the currently input data, determining the number of generation of the sustain discharge pulses according to the calculated load ratio and the result of the contrast phase division, and outputting information on the number of sustain discharge pulses; Automatic power control method of the plasma display panel comprising a. The method of claim 9, The first step, And a lower limit value of the sustain discharge pulse generating step is determined differently according to the contrast step. The method of claim 9, The first step, And controlling the number of sustain discharge pulses according to each sustain discharge pulse generation step according to the contrast step. The method of claim 9, The second step, The contrast step is divided by a photoconductive element whose resistance is changed by light. Automatic power control method of plasma display panel. The method of claim 9, The third step, Outputting information on the number of sustain discharge pulses corresponding to the current load ratio through a predetermined calculation process based on the table information stored in the contrast step and the first step Automatic power control method of plasma display panel.