KR100237203B1 - Plasma display device and its driving method - Google Patents

Abstract

The present invention provides a method of driving a plasma display device in which an entire screen of a plasma display panel (hereinafter referred to as a PDP) is divided into upper and lower X blocks, and one frame screen of each block is divided into a plurality of subfield screens. The present invention relates to a plasma display device and a driving method thereof, by supplying a scan pulse and an address pulse to a remaining block while a sustain pulse is supplied to some blocks of the X blocks to maintain a discharge generated just before. Since the remaining blocks (two to four) are simultaneously selected and addressed while the discharge of the block is maintained, the PDP can be driven at a slower speed than the prior art, or the brightness and contrast of the entire screen can be improved, and each block can be improved. When configuring the visual axis arrangement order of a plurality of subfield screens differently for each block Image quality is improved by minimizing the contour noise appearing on the PDP screen.In the initial stage of driving of the PDP, the discharge does not occur on the entire screen of the PDP for a predetermined time or only a minute discharge occurs. The noise is minimized to improve the image quality.

Description

Plasma Display and Driving Method

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a plasma display device and a method of driving the same, and more particularly, to a plasma display device which displays a plurality of subfield screens according to a gradation to implement one frame screen of a plasma display panel (hereinafter referred to as a PDP) It relates to a driving method.

As the modern society is called an information society, the importance of the image display device is increasing with the development and spread of the information processing system, and the types thereof are gradually diversifying.

CRT (Cathode Ray Tube), which has been used most often as an image display device, has various problems such as large size, high operating voltage, and distortion of display. Recently, research and development of various flat display devices having a matrix structure have been actively conducted.

A plasma display device is a device that includes a PDP, which is a light emitting device, and displays a moving image or a still image by using a gas discharge phenomenon inside the PDP.

A configuration of one of the plasma display devices according to the prior art will be described with reference to FIG.

In FIG. 1, reference numeral 110 denotes 640 R (Red), G (Green), B (Blue) address electrode lines R1, G1, B1, ..., R640, G640, B640, hereinafter referred to as vertical electrode lines. A three-electrode surface discharge PDP having 480 first and second sustain electrode line pairs (S1, S2, ..., S479, S480, hereinafter referred to as horizontal electrode lines) is shown.

The three-electrode surface discharge PDP 110 is one of the most commonly used PDPs. Although not shown in the drawing, 480 horizontal electrode lines S1 to S480 are arranged on the front substrate, and the predetermined distance from the front substrate. 640 R, G, and B vertical electrode lines R1 to B640 are arranged orthogonal to each horizontal electrode line S1 to S480 on the back substrate disposed in parallel with each other so that the entire screen is 640 × 480 in a matrix form. It consists of several pixels (pixel, R, G, B cells).

In FIG. 1, reference numeral 120 digitizes externally inputted R, G, and B image data to output 8-bit R, G, and B digital image data (256 gray scale implementations), and the digital image data and the external signal. The microcomputer outputs various control signals required for driving the three-electrode surface discharge PDP 110 according to the present invention.

In FIG. 1, reference numeral 130 denotes a scan pulse to 480 horizontal electrode lines S1 to S480 according to the control signal of the microcomputer 120 to sequentially scan one line at a time, and then all horizontal electrode lines ( A scanning and sustain driving unit for supplying a sustain pulse to S1 to S480 to maintain discharge and light emission of each cell is shown.

The scanning and sustain driver 130 generates a clock signal CLK and a data signal Do according to a control signal of the microcomputer 120, and outputs the clock and data generator 131 to the microcomputer 120. The clock signal CLK and the data signal in a state where the sustain pulse generator 132 generates and outputs a sustain pulse according to a control signal, and 30 lines are connected to the 480 horizontal electrode lines S1 to S480 in order. It consists of first to sixteenth driving ICs (Integrated Circuits 133a to 133p) which sequentially supply scan pulses to the 480 horizontal electrode lines S1 to S480 according to (Do) and the sustain pulses, and then simultaneously supply the sustain pulses. have.

In FIG. 1, reference numeral 140 denotes a memory unit for storing R, G, and B digital image data output from the microcomputer 120 for each frame, color, and bit, and 150 denotes a scan by the scanning and sustain driver 130. An address driver for reading bit values of 640 R, G, and B digital image data corresponding to horizontal electrode lines from the memory unit 140 and supplying the bit values of the 640 R, G, and B vertical electrode lines R1 to B640. Indicates.

A process of displaying an image of 256 gray scales on a PDP screen according to a subfield method by a plasma display device according to the related art configured as described above is as follows.

The subfield method is a method of dividing and displaying one frame screen into X subfield screens to implement 2 ^x grayscale, and digitizing externally input image data into X bit digital image data and supplying the PDP.

Each subfield screen is composed of a reset period, an address period, and a sustain period. Among them, the reset period and the address period are all identically assigned to each subfield, but the sustain period is the bit weight of the digital image data displayed in the address period. Are differently assigned according to each other, and gray scale implementation of the image is possible by combining each subfield (using the integration effect of the eyes).

Accordingly, the microcomputer 120 digitizes R, G, and B image data externally inputted to implement 256 gray scales, and thus, 8-bit R, G, and B digital image data (lowest bit value B1 to highest bit value B8). And various control signals required for driving the PDP 110 according to the digital image data and the external signal.

At this time, the 8-bit R, G, B digital image data output from the microcomputer 120 is stored in the memory unit 140 for each frame, color, and bit.

Thereafter, in the reset period and the address period of the first to eighth subfield screens SF1 to SF8, the first to sixteenth drive ICs 133a to 133p move to the previous horizontal electrode lines S1 to S480 in one step. Erase pulses to remove wall charges generated in the second stage; write pulses to form even wall charges throughout the three-electrode surface discharge PDP 110 in two stages; and erase pulses in three stages to supply 640 R Wall charges are formed on the G and B vertical electrode lines R1 to B640 so that the voltages of the address pulses supplied thereafter are lowered. In step 4, according to the clock signal CLK, the data signal Do, and the sustain pulse, Scan pulses are sequentially supplied to the 480 horizontal electrode lines S1 to S480 one by one.

Referring to the fourth step of supplying the scan pulse in more detail, first, the first driver IC 133a receives a scan signal generated by the data signal Do and the sustain pulse when the data signal Do is input. In synchronization with (CLK) and sequentially supplied to the 30 horizontal electrode lines (S1 to S30), the second driver IC 133b is also a clock signal (CLK) when the last output of the first driver IC (133a) is input ), The scan pulses are sequentially supplied to the 30 horizontal electrode lines S31 to S60, and the 30 horizontal electrode lines S451 to S480 of the 16th driving IC 133p are sequentially supplied. When the scan pulse is supplied, the scanning of the 480 horizontal electrode lines S1 to S480 is completed.

In addition, when supplying the scan pulses in the fourth step, the address driver 150 transmits address pulses (1 bit value of R, G, B digital image data) corresponding to the horizontal electrode lines to which the scan pulses are supplied and scanned. By synchronizing with each of the 640 R, G, and B vertical electrode lines R1 to B640, the discharge occurs within the discharge space of each cell supplied with the logic “high” by the address pulse.

At this time, the address driver 150 converts the 8-bit R, G, and B digital image data B1 to B8 corresponding to each cell from B _{1 to} SF ₁ , B _{2 to} SF ₂ ,. It supplies to B7 → SF7, B8 → SF8, respectively.

On the other hand, when the address period of each subfield screen SF1 to SF8 is completed, the first to sixteenth driving ICs 133a to 133p receive the sustain pulses from the sustain pulse generator 132 to provide the entire horizontal electrode lines S1 to S480. ) SF1: SF2:… SF7: SF8 = 2 ⁰ : 2 ¹ :... A number of sustain pulses proportional to 2 ⁶ : 2 ⁷ (luminance relative ratio) is supplied so that the discharge and light emission of some cells in which the discharge occurs in the address period are maintained during the sustain pulse period (sustain period).

When the configuration of the first to eighth subfield screens SF1 to SF8 is completed through the above process, 256 gray scale images are displayed on the three-electrode surface discharge PDP 110.

However, since the plasma display device according to the prior art sequentially scans a plurality of horizontal electrode lines provided in the PDP one by one for each address period of each subfield screen, the driving speed is very high, power consumption is high, and manufacturing costs are high. Heard, there was a short life problem.

In addition, the conventional plasma display device displays a plurality of subfield screens in order of brightness (luminance) for the entire screen of the PDP to form a one-frame screen, so that contour noise appears on the PDP screen. Since the PDP starts to be driven at the same time as the power supply, excessive wall charges are formed in the discharge space of the entire cell, resulting in various noises appearing on the PDP screen, and uniformity.

SUMMARY OF THE INVENTION The present invention has been made to solve the problems of the prior art, and the remaining blocks (2 to 4) are simultaneously operated while the discharge of some blocks is maintained by dividing and driving the entire screen of the PDP into a plurality of blocks. It is an object of the present invention to provide a plasma display device and a method of driving the same, which selectively reduce the driving speed or improve the brightness and contrast of the entire screen.

In addition, the present invention provides a plasma display device in which the contour noise appearing on the PDP screen is minimized by configuring the visual axis arrangement order of the plurality of subfield screens differently for each block when displaying one frame screen of each block into a plurality of subfield screens. It is another object to provide the driving method.

In addition, the present invention provides a plasma display device and a driving method thereof in which various noises appearing on the PDP screen at the initial supply of power are minimized by discharging the entire screen of the PDP for a predetermined time or only minute discharge in the initial stage of driving of the PDP. There is another purpose in providing this.

1 is a block diagram showing a configuration of one of the conventional plasma display devices.

2 is a block diagram showing a configuration of a plasma display device according to an embodiment of the present invention.

3 is a timing diagram of selection signal waveforms supplied to each driving IC by a driving IC control unit shown in FIG.

4 is a timing diagram of scan pulse waveforms supplied to a corresponding block by driving ICs simultaneously selected in FIG.

5 is a gray scale implementation diagram of a full screen according to an embodiment of the present invention.

* Explanation of symbols for main parts of the drawings

10: 3-electrode surface discharge PDP 20: microcomputer

30: block driver 31: clock and data generator

32: sustain pulse generator 33a to 33p: first to 16 driving ICs

34: driving IC control section 40: memory section

50: address driver 60: initial driver

In order to achieve the above object, a method of driving a plasma display device according to the present invention includes a plurality of frames having relatively different luminance ratios in one frame in a plasma display panel including a plurality of cells having a data electrode, a scan electrode, and a sustain electrode. A method of driving a plasma display device divided into subfields, wherein the scan electrodes are grouped to divide a screen into X blocks having the same number of scan electrode lines (X is an integer of 2 or more), and the X Simultaneously select two or more blocks from among blocks to sequentially perform a scan pulse and an address pulse supply operation to the scan electrodes of the corresponding blocks, and repeat the pulse supply operation until the scan electrode lines are driven. It is characterized in that it comprises an injection step.

Further, the plasma display device according to the present invention outputs digital image data by digitizing a plasma display panel (hereinafter referred to as PDP) having a plurality of scan electrodes, data electrodes and sustain electrodes, and analog image data input from the outside. And a microcomputer for generating and outputting various control signals for driving the PDP according to the digital image data and an external signal, and X having the same number of scan electrode lines by grouping the plurality of scan electrode lines. X scan driver for sequentially scanning scan pulses to two or more block scan lines selected by the microcomputer by dividing into blocks; and a memory unit for temporarily storing digital image data generated and output by the microcomputer; Bit value of digital image data corresponding to scan line selected by micom And an address driver which reads the data from the memory and applies it to the data electrode.

Hereinafter, with reference to the accompanying drawings an embodiment of the present invention will be described in more detail.

In the method of driving a plasma display device according to an embodiment of the present invention, the entire screen of the PDP is divided into 16 blocks at the top and bottom, and one frame screen of each block is divided into 8 subfield screens (256 gray scales are implemented). The sustain pulses are supplied to some of the 16 blocks to supply the scan pulses and the address pulses to the remaining blocks (2 to 4) while the discharge occurs just before.

That is, scan pulses and address pulses are sequentially supplied to two to four blocks of the sixteen blocks so that discharge of two to four blocks occurs at the same time. Do not discharge on the entire screen of the PDP.

In the plasma display device according to the exemplary embodiment of the present invention which performs the above driving method, as shown in FIG. 2, 640 address electrode lines R1, G1, B1,..., R640, G640, B640 or less are vertical. A three-electrode surface discharge PDP 10 having an electrode line) and 480 first and second sustain electrode line pairs (S1, S2, ..., S479, S480, hereinafter referred to as horizontal electrode lines); R, G, B image data input from outside is digitized to output 8-bit R, G, B digital image data (lowest bit value B1 to highest bit value B8), and according to the digital image data and an external signal, A microcomputer 20 for outputting various control signals required for driving the three-electrode surface discharge PDP 10; The 480 horizontal electrode lines S1 to S480 are driven by dividing each of the blocks into 30 blocks in total of 16 blocks, and the 16 blocks are simultaneously scanned 2 to 4 blocks in accordance with the control signal of the microcomputer 20, while the remaining blocks A block driver 30 which supplies a sustain pulse for sustaining discharge; A memory unit 40 for storing R, G, and B digital image data output from the microcomputer 20 for each frame, color, and bit; The 640 R, G, and B vertical electrode lines R1 are read from the memory unit 40 by reading bit values of R, G, and B digital image data corresponding to the horizontal electrode lines scanned by the block driver 30. An address driver 50 for supplying to B640; Upon initial supply of power, the block driver 30 is controlled according to a control signal of the microcomputer 20 to the initial driver 60 to prevent a driving pulse from being supplied to the sixteen blocks S1 to S480 for a predetermined time. Consists of.

The block driver 30 generates a clock signal CLK and a data signal Do according to the control signal of the microcomputer 20, and outputs the clock and data generator 31 and the control of the microcomputer 20. The clock signal CLK, the data signal Do, and the sustain pulse in a state where the sustain pulse generator 32 generates and outputs a sustain pulse according to the signal, and is connected in a one-to-one correspondence with the sixteen blocks S1 to S480. First to sixteenth drive ICs 33a to 33p that receive parallel inputs and sequentially supply scan pulses or sustain pulses to the corresponding blocks, and the first to sixteenth drive ICs according to control signals of the microcomputer 20; It consists of the drive IC control part 34 which selects 2-4 drive IC which should output a scan pulse among 33a-33p).

A process of displaying an image of 256 gray scales on a PDP screen by a plasma display device according to an exemplary embodiment of the present invention configured as described above is as follows.

First, the microcomputer 20 digitizes R, G, and B image data externally inputted to implement 256 gray scales, and has 8-bit R, G, and B digital image data (lowest bit value B1 to most significant bit value B8). And various control signals required for driving the PDP 10 according to the digital image data and an external signal.

At this time, the R, G, and B digital image data output from the microcomputer 20 are stored in the memory unit 40 for each frame, color, and bit.

Thereafter, the driving IC control unit 34 performs addressing of the subfield screens SF1 to SF8 of some blocks according to the control signal of the microcomputer 20 and the output signals CLK and Do of the clock and data generator 31. In order to supply the selection signals to two to four driving ICs, the driving ICs supplied with the selection signals synchronize 30 scan pulses generated by the data signal Do and the sustain pulses with the clock signal CLK. Supply to the horizontal electrode line sequentially.

Selection signals supplied by the driving IC control unit 34 to the first to sixteenth driving ICs 33a to 33p for one frame (40 horizontal periods: one horizontal period is a time for scanning 30 x 4 horizontal electrode lines). 30 horizontal electrodes in which the timing diagram of the waveforms is shown in FIG. 3 (the logic “low” pulses in FIG. 3 correspond to the selection signal) and the drive ICs simultaneously selected by the drive IC controller 34 are connected to each other. The timing diagram of the scan pulse waveforms supplied to the line (the scan pulse train supplied to the 30 horizontal electrode lines connected to each of the first, third, 9, and 11 driving ICs during the first horizontal period as an example) is shown in FIG. It is.

As shown in FIG. 4, the driving ICs simultaneously selected above supply scan pulse trains having mutual phase differences to the corresponding horizontal electrode lines, thereby preventing images from being displayed on the plurality of horizontal electrode lines.

In addition, when a scan pulse is supplied to an arbitrary horizontal electrode line, the address driver 50 receives an address pulse (640 R, G, B bit values of digital image data) corresponding to the horizontal electrode line. And B are supplied to the B vertical electrode lines R1 to B640, respectively, so that discharge occurs in the discharge space of each cell supplied with the logic “high” by the address pulse.

At this time, the address driver 50 similarly as in the prior art that the R, G, B digital image data (B1~B8) of the 8-bit B ₁ → SF1, SF2 → B2, corresponding to each cell ... It supplies to B7 → SF7, B8 → SF8, respectively.

In addition, when the address period of each subfield screen SF1 to SF8 for each block is completed, the first to sixteenth drive ICs 33a to 33p input sustain pulses from the sustain pulse generator 32 as in the prior art. Accept the corresponding block SF1: SF2:… SF7: SF8 = 1: 2: 4: 8: 16: 32: 64: Supplying sustain pulses proportional to 128 (relative luminance ratio), discharge and light emission of some cells discharged in the address period It is maintained for the supply period (sustain period).

To facilitate understanding of the above description, the driving ICs selected by the driver IC control unit 34 for each horizontal period and the bit weights of the digital image data supplied by the address driver 50 at that time are shown in Tables 1A and 1B below. .

In the above, the first to sixteenth drive ICs 33a to 33p and the address driver 50 block blocks 1, 2, 9, and 10 of the PDP 10 according to Tables 1a and 1b for 40 horizontal periods. , SF5, SF4, SF3, SF2, SF1, and blocks 3, 4, 11, and 12 in the order of SF7, SF6, SF5, SF4, SF3, SF2, SF1, SF8, and 5, 6 , Blocks 13, 14 are composed of SF8, SF2, SF3, SF4, SF5, SF6, SF7, SF1, and blocks 7, 8, 15, and 16 are composed of SF2, SF3, SF4, SF5, SF6, SF8, In the order of SF7 and SF1, 256 gray scale images are displayed on the entire screen of the PDP 10.

The configuration of the entire screen as described above is shown in FIG. 5, and as can be easily seen in FIG. 5, an embodiment of the present invention provides the remaining block (two blocks) while the discharge of some blocks is maintained (during the sustain period). To 4) at the same time by reducing the time that can not be used for discharge, that is, by increasing the discharge efficiency, it is possible to drive the PDP at a lower speed than the prior art, or more discharge sustain period (sustain period) than the prior art in one frame It is possible to improve the brightness and contrast of the entire screen.

In addition, the embodiment of the present invention can obtain the effect that the contour noise does not appear visually by dispersing the contour noise of the entire screen through the screen division of the PDP (10).

On the other hand, when a message is supplied at the beginning of the system, the initial driver 60 controls the driver IC controller 34 according to the control signal of the microcomputer 20 so that the first to sixteenth drive ICs 33a to 33p for a predetermined time. By not driving the pulses to the horizontal electrode lines S1 to S480, the screen driving is started while the screen of the PDP 10 is stabilized.

Therefore, in one embodiment of the present invention, various noises that may appear at the beginning of driving of the PDP are minimized and screen uniformity is improved.

In another embodiment, the present invention provides only a driving pulse for microdischarge to the entire screen of the PDP for a predetermined time instead of the initial driving unit not to supply the driving pulse to the entire screen of the PDP for a predetermined time at the beginning of the driving of the PDP. An initial driving unit may be provided to achieve the same effect as that of the embodiment of the present invention described above (minimizing noise and improving screen uniformity).

As described above, the plasma display device and the driving method thereof according to the present invention select the remaining blocks (two to four) simultaneously while the discharge of some blocks is maintained by dividing and driving the entire screen of the PDP into a plurality of blocks. Because of the addressing, the PDP can be driven at a lower speed than the prior art, or the luminance and contrast of the entire screen can be improved.

In addition, the present invention configures the visual axis arrangement order of the plurality of subfield screens differently for each block when displaying one frame screen of each block into a plurality of subfield screens, thereby minimizing outline noise appearing on the PDP screen, thereby improving image quality. It is effective.

In addition, since the present invention prevents discharge from occurring on the entire screen of the PDP for a predetermined time or only minute discharge in the initial stage of driving of the PDP, various noises appearing on the PDP screen during initial supply of power are minimized to improve image quality. have.

Claims (8)

In a plasma display panel including a plurality of cells having a data electrode, a scan electrode, and a sustain electrode, a driving method of a plasma display device is performed by dividing one frame into a plurality of subfields having relatively different luminance ratios. The screen is divided into X (X is an integer of 2 or more) blocks having the same number of scan electrode lines, and two or more blocks of the X blocks are simultaneously selected to sequentially scan line of the block. And performing a scanning pulse and an address pulse supply operation to the data electrode, and repeating the pulse supply operation until the scan electrode line is driven. The method of claim 1, wherein the blocks are divided into 16 blocks and 2 to 4 blocks are selected at the same time. The method of claim 1, wherein the discharge is not generated on the entire screen of the PDP for a predetermined time so that the screen is stabilized at the initial stage of driving of the PDP. The method of claim 1, wherein only a minute discharge occurs on the entire screen of the PDP for a predetermined time so that the screen is stabilized at the initial stage of driving of the PDP. Plasma display panel (hereinafter referred to as PDP) including a plurality of scan electrodes, data electrodes and sustain electrodes, and analog image data input from the outside are digitized to output digital image data, and according to the digital image data and the external signal. The microcomputer generates and outputs various control signals required for driving the PDP, and the plurality of scan electrode lines are grouped into X (X is an integer of 2 or more) blocks having the same number of scan electrode lines, and the microcomputer divides the blocks by the micom. X scan driving units for sequentially supplying scan pulses to two or more selected block scanning lines, a memory unit for temporarily storing digital image data generated and output by the micom, and a digital corresponding to the scan line selected by the micom. The bit value of the image data is read from the memory and the data is read. Display display device comprising: an address driver for applying to the electrode. The method of claim 5, further comprising an initial driver for controlling the scan driver in accordance with the control signal of the microcomputer during the initial supply of power to prevent the driving pulse is supplied to the X blocks for a predetermined time. Plasma Display. The apparatus of claim 5, further comprising an initial driver configured to control the scan driver according to the control signal of the microcomputer to supply only the driving pulse for the minute discharge to the X blocks for a predetermined time. Plasma display device characterized in that. The semiconductor device of claim 5, wherein the scan driver generates and outputs a clock signal and a data signal according to the control signal of the microcomputer, and a sustain pulse that generates and outputs a sustain pulse according to the control signal of the microcomputer. First to X driving ICs that receive the clock signal, the data signal, and the sustain pulse in parallel with the generator and the X blocks in a one-to-one correspondence, and sequentially supply scan pulses or sustain pulses to the corresponding blocks. (Integrated Circuit) and a drive IC control unit for selecting two to four drive ICs that should output a scan pulse of the first to X drive ICs according to the control signal of the microcomputer.

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