KR100479112B1 - Operation method of 3-electrode side discharge plasma display panel - Google Patents

Abstract

According to the present invention, the discharge sustain periods are 2 ⁰ : 2 ¹ : 2 ² : 2 to display 2 ^χ gray scale images on a three electrode surface discharge plasma display panel (hereinafter referred to as a three electrode surface discharge PDP). ³ :… : ^Χ 2 for the X sub-fields time provided the (sub-field) display is assigned as ^-1 in combination ratio selecting a cell unit constituting one frame screen, and the discharge sustain period of each subfield, the screen 2 ^0: 2 ¹ : 2 ² : 2 ³ :. : A method of driving a three-electrode surface discharge PDP which allocates a part or all of the dead time remaining after the construction of one frame screen by allocating at a ratio of 2 ^{χ −1} to each of the discharge sustain periods of the X subfields. According to the above configuration, the discharge sustain period is additionally allocated to each subfield according to the above configuration, thereby increasing the luminance of the PDP screen significantly.

Description

Driving method of 3-electrode surface discharge plasma display panel

The present invention relates to a method of driving a three-electrode surface discharge plasma display panel (hereinafter referred to as a three-electrode surface discharge PDP), and in particular, the three-electrode surface discharge PDP according to the ADS subfield method (Addressing and Display System sub-field method). A method of driving a three-electrode surface discharge PDP for displaying a gray scale image on an image.

As the modern society is called the information society, the importance of display increases with the development and spread of information processing system, and its kinds are gradually diversified.

CRT (Cathode Ray Tube), which has been the most used display for a long time, has various problems such as large size, high operating voltage, and distortion of display. Recently, research and development of various flat displays having a matrix structure have been actively progressed since they are not suitable.

Among the flat panel displays, PDP (Plasma Display Panel) is in the spotlight as the next-generation large-screen flat panel display. The PDP is applied to a wall-mounted television, a home theater display, various monitors, etc. due to its large screen and thin thickness.

1 shows a simplified configuration of a three-electrode surface discharge PDP, one of the most used PDPs, and a driving device for displaying a moving image or still image on the three-electrode surface discharge PDP. have.

In FIG. 1, reference numeral 10 denotes N scan electrodes Y1 to YN and N common electrodes X1 to XN that are alternately arranged in parallel with each other, and the scan electrodes Y1 to YN and common electrodes ( A three-electrode surface discharge PDP having M address electrodes A1 to AM arranged to be orthogonal with X1 to XN and a predetermined space therebetween is shown. Here, one end of the common electrodes X1 to XN is connected in common, and the scan electrodes Y1 to YN are independent from each other, and the N scan electrodes Y1 to YN and the common electrodes X1 to XN are respectively connected. And cells are formed at each intersection of the M address electrodes A1 to AM, and the entire screen of the three-electrode surface discharge PDP 10 is composed of M × N cells in a matrix form.

The configuration of each cell of the three-electrode surface discharge PDP 10 will be described by taking the cells of the i-th row and the j-th column shown in FIG. 2 as an example.

First, the i-th scan electrode Yi and the i-th common electrode Xi parallel to each other are formed on one surface of the front substrate 11 which is the display surface of the image, and the scan electrode Yi and the common electrode Xi are A dielectric layer 12 is formed on the dielectric layer 12 to limit the discharge current during discharge and to facilitate the generation of wall charges. ) And a magnesium oxide (MgO) protective film 13 for protecting the dielectric layer 12 is formed.

Further, the j-th address electrode Aj is formed on the opposite surface to the front substrate 11 among the rear substrates 14 disposed in parallel with the front substrate 11 at a predetermined distance therebetween, and the front substrate ( The first and second barrier ribs 15a and 15b are arranged between the 11 and the rear substrate 14 to prevent inter-cell mixing and to secure a discharge space. The first and second barrier ribs 15a and 15a are arranged on the address electrode Aj. Phosphor 16 is applied to a part of, 15b), and discharge gas is injected into the discharge space.

The basic driving principle of each cell of the three-electrode surface discharge PDP 10 configured as described above generates a discharge between the scan electrode Yi and the address electrode Aj to make the discharge gas into a plasma state and generate ultraviolet rays. The phosphor 16 is excited to generate visible light, and discharges between the scan electrode Yi and the common electrode Xi to maintain the generation of visible light.

In addition, in FIG. 1, reference numeral 20 denotes a Y driving unit in which one end of the scan electrodes Y1 to YN is connected to the output terminal in a one-to-one correspondence, and 30 denotes one end of the common electrodes X1 to XN to the output terminal. 40 denotes an X driver connected in common, 40 denotes an address driver in which one end of the address electrodes A1 to AM is connected to the output terminal in a one-to-one correspondence, and 50 denotes various driving voltage waveforms and controls according to various external inputs. The control part which generates a signal and supplies it to the said X drive part 20, the Y drive part 30, and the address drive part 40 is shown.

More specifically, the controller 50 digitizes the analog image signal IMAGE input from the outside to output a digital image signal, and the digital image signal, the clock CLK, the horizontal synchronization signal HS and the vertical synchronization signal VS) generates various driving voltage waveforms and control signals.

On the other hand, the gray scale implementation of each cell of the three-electrode surface discharge PDP 10 configured as described above is implemented through the number of discharges per unit time due to difficulty in adjusting the strength and weakness of the discharge, and for each frame. When the number of discharges of a cell is discharged by dividing it into 0 to 2 ^χ -1 times, the brightness of each cell changes according to the number of discharges during one frame, resulting in an image of 2 ^χ gray scale displayed on the entire screen.

One of the gradation implementation methods based on the above concept is the ADS subfield method, in which each cell operates in two states of on and off and implements 2 ^χ gray ^scales. By using a binary X bit system based on the above, one frame is divided and driven into X subfields having different discharge counts (ie, discharge sustain periods).

Next, an image display process according to the conventional ADS subfield method will be described in more detail.

First, one frame is divided driven with the X sub-fields, each subfield is divided driven with a reset period and an address period and a discharge sustain period, the reset period is over sseoneotgi period and a full erase period for 2 ^χ tone implementation Divided driving.

In the above write-in period of each subfield, a three-electrode surface discharge is applied by applying a writing pulse having a voltage higher than the discharge start voltage between all scan electrodes Y1 to YN and common electrodes X1 to XN. Is a period in which all the cells of the PDP 10 are discharged and emitted to generate wall charges therein,

The entire erase period is an erase pulse between the scan electrodes Y1 to YN and the common electrodes X1 to XN that is lower than the discharge start voltage and is the same polarity as the wall charge generated in the previous write period. Is a period of erasing the inner wall charge of each cell by applying

In the address period, an address pulse having a voltage lower than the discharge start voltage is selectively applied between all the scan electrodes Y1 to YN and the address electrodes A1 to AM in accordance with the digital image signal so that the address pulse is applied. It is a period of time when only the applied cells are turned on to generate wall charges therein.

The discharge sustain period is a voltage lower than the discharge start voltage between all the scan electrodes Y1 to YN and the common electrodes X1 to XN and a sustain pulse having the same polarity as the wall charge generated in the immediately preceding address period. Is a period in which discharge and light emission of the cells turned on in the address period are maintained.

In the above, the brightness of each subfield screen also takes into account the brightness due to the write discharge in the reset period and the address discharge in the address period, but for convenience of understanding, the write discharge and the address discharge do not contribute to the brightness of the screen and sustain the discharge sustain period. Assume that only the discharge contributes to the brightness of the screen.

In addition, each subfield screen is changed according to a change in the frequency (the number applied per unit time) and the width of the sustain pulse applied between the scan electrodes Y1 to YN and the common electrodes X1 to XN during the discharge sustain period. In addition, the brightness of the 1-frame screen is also increased or decreased. That is, when the number of sustain pulses applied during the predetermined discharge sustain period increases or the width of each sustain pulse increases, the overall screen luminance of the three-electrode surface discharge PDP 10 increases.

A process of displaying a digital image signal on a three-electrode surface discharge PDP according to the conventional ADS subfield method described above will be described below.

3 is a timing diagram of some driving voltage waveforms applied to the electrodes of the three-electrode surface discharge PDP 10 according to the conventional ADS subfield method.

First, as shown in FIG. 3, all common electrodes X1 to XN are applied to the entire scan electrodes Y1 to YN and address electrodes A1 to AM in the entire surface write period of each subfield. ), A write pulse of Vw voltage is applied to generate a write discharge between all of the scan electrodes Y1 to YN and the common electrodes X1 to XN, thereby generating wall charges inside each cell. .

After that, in the entire erasing period, a voltage of Vs is applied to the common electrodes X1 to XN and a pulse of 0 V is applied to all the scan electrodes Y1 to YN while 0 V is applied to the address electrodes A1 to AM. To erase the internal wall charge of the entire cell.

N scans in the address period of each subfield with Vs voltage applied to all scan electrodes Y1 to YN and common electrodes X1 to XN and 0 V applied to all address electrodes A1 to AM. A scan pulse of 0 V is sequentially applied to the electrodes Y1 to YN one by one, and an image pulse of Va voltage synchronized with the scan pulse is selectively applied to all the address electrodes A1 to AM. It is applied to cause the address discharge to occur only inside the cell to which the address pulse of Va voltage is applied between the scan electrode and the address electrode.

In the discharge sustain period of each subfield, the entire scan is applied while the Vs voltage is applied to all the scan electrodes Y1 to YN and the common electrodes X1 to XN and 0 V is applied to all the address electrodes A1 to AM. An alternate 0V pulse is applied to the electrodes Y1 to YN and the common electrodes X1 to XN to maintain the discharge and light emission of the cells turned on in the immediately preceding address period.

The voltage pulses Vw, Vf (discharge start voltage), Vs, and Va applied to each electrode are set to voltage values satisfying Vw Vf Vs Va and Vf Vw-Vs, and the address is applied during the address period of each subfield. The image pulses applied to the electrodes A1 to AM correspond to one bit value of the X bit digital image signal (lowest bit B1 to highest bit BX) corresponding to each cell, and more specifically, the first subfield. B1 during the address period of < RTI ID = 0.0 > and B2 < / RTI > during the address period of the second subfield. During the address period of the Xth subfield, BX is respectively applied.

In addition, various driving voltage waveforms shown in FIG. 3 are applied to the corresponding electrodes through the Y driver 20, the X driver 30, and the address driver 40, respectively, and the timing is controlled by the controller 50. .

On the other hand, when an analog image signal continuously input from the outside is an image signal transmitted in a sequential system, for example, a VGA (Video Graphic Array) signal, one frame screen is configured for 1/60 seconds (about 16.67 ms). Should be.

According to the ADS subfield method of the conventional art described in the second discharge sustain period of the first X to the sub-fields for implementing gray levels of ^χ are each 2 ^0: 2 ^1: 2 ^2: 2 ^3: ... : The ratio of 2 ^{χ -1} , which is the 1/60 second driving time of the sequential signal, is the discharge duration period relative to each subfield except the reset period and the address period of each subfield ^. : 2 ¹ : 2 ² : 2 ³ :…: 2 ^{χ- 1} ) After dividing and assigning a frame, a predetermined time remains after the composition of one frame screen is started before the start of the next frame.

For example, when displaying 256 gray scale images on a three-electrode surface discharge PDP with a resolution of 640x480, about 1 to 1.3 ms after the configuration of one frame screen and before the start of the next frame is started. There will be time left.

That is, in the case of 256 gray scale implementation, the address period in one frame is 3 ms (address period) × 480 (number of scanning electrodes) × 8 (number of subfields for 256 gray scale implementation) = 11.52 ms, and the reset period is 300 ms (1). Reset period in the subfield) × 8 (the number of subfields for 256 gray scale implementation) = 2.4 ms, and the discharge sustain period in one frame is theoretically 16.67 ms-11.52 ms-2.4 ms = 2.75 ms, but the discharge sustain of each subfield is maintained. Except for the dead time of 1 to 1.3 ms that is lost to match the relative ratio of the period length, the discharge sustain period within an actual frame is only 2.75 ms to 1 ms (to 1.3 ms) = 1.45 ms (to 1.75 ms). It doesn't work.

As mentioned above, the screen brightness of the three-electrode surface discharge PDP is determined by the length of the discharge sustain period in one frame. If the sustain period in one frame is partially lost to match the relative ratio of the discharge sustain period in each subfield, the brightness is increased. The brightness of the three-electrode surface discharge PDP screen, which has a large weakness, is further lowered, which causes an obstacle to practical use.

The present invention has been made to solve the above problems, and the discharge sustain period is limited by the invalid time remaining after the configuration of each frame screen in driving of the PDP, which is disadvantageous to the luminance determined by the discharge sustain period. It is to provide a method of driving a three-electrode surface discharge PDP that can improve the problem that occurs.

Method of driving a three-electrode surface according to the present invention in order to accomplish the above object, a discharge PDP is a 2 ^χ gradation (gray scale) image on a three-electrode surface discharge plasma display panel (hereinafter referred to as a three-electrode surface discharge PDP) In order to display, the discharge sustain periods are respectively 2 ⁰ : 2 ¹ : 2 ² : 2 ³ :. A method of driving a three-electrode surface discharge PDP in which one sub-frame screen is configured by selecting and combining X sub-field screens allocated at a ratio of 2 ^{χ −1} for a predetermined time period in a cell unit, wherein each sub-field The discharge sustain period of the screen is 2 ⁰ : 2 ¹ : 2 ² : 2 ³ :. And allocating part or all of the dead time remaining after the configuration of one frame screen by allocating at a ratio of 2 ^{× -1} to each of the X subfields.

According to an embodiment of the present invention, it is preferable that the invalid time remaining after the configuration of the one-frame screen is allocated to the discharge sustain periods of the X subfields by the same time.

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

Since the three-electrode surface discharge PDP to which an embodiment of the present invention is applied is the same as the configuration of the general three-electrode surface discharge PDP shown in FIGS. 1 and 2, description thereof will be omitted.

According to an embodiment of the present invention, a method of driving a three-electrode surface discharge PDP is based on 2 ⁰ : 2 ¹ : 2 ² : 2 ³ :... : Allocating a discharge sustain period proportional to 2 ^{χ −1} , respectively, allocates an invalid time t1 remaining after the configuration of each frame screen by dividing the same time α by the discharge sustain period of the first to X subfields, respectively. Therefore, the relative ratio of the lengths of the discharge sustain periods of the first to X subfields is 2 ⁰ + α : 2 ¹ + α : 2 ² + α : 2 ³ + α:. : 2 ^{χ -1} + α (Where X × α ≦ t1). That is, the discharge sustain periods of each subfield constituting one frame are all increased by a predetermined amount α from the prior art.

For example, when displaying one frame image of 256 gray levels on a 640 × 480 resolution three-electrode surface discharge PDP for 1/60 seconds according to the conventional ADS subfield method, as shown in FIG. When the invalid time of 1 to 1.3 ms remaining after the configuration is additionally assigned to the discharge sustain period of the first to eighth subfields SF1 to SF8 by α = 0.1 ms as shown in FIG. 5, the discharge sustain period within one frame 0.8 ms is increased from the prior art (1.45 to 1.75 ms).

As described above, when the discharge sustaining period of 0.1 ms is increased for each of the first to eighth subfields SF1 to SF8, a sustain pulse of the same frequency as that of the prior art (the frequency of the sustain pulse used in a general system is 100 Hz → the period 10 Hz) is obtained. When applied to the scan electrodes and the common electrodes of the 3-electrode surface discharge PDP, the result is that about 10 sustain pulses are additionally applied for each additional discharge sustain period α of each subfield, resulting in sustain discharge of each cell. As the number of times increases, the brightness of the three-electrode surface discharge PDP screen is greatly increased (see FIG. 3).

In addition, instead of increasing the number of sustain pulses applied to the electrodes of the three-electrode surface discharge PDP during the additional discharge sustain period α of the first to eighth subfields SF1 to SF8 as described above, The luminance of the three-electrode surface discharge PDP screen can be increased even if the width (W in FIG. 3) of each sustain pulse is constantly increased in the presence of the sustain pulse.

In addition, instead of allocating a part of the invalid time t1 remaining after the configuration of the one-frame screen as the discharge sustain period of each subfield, respectively, the entire invalid time t1 is respectively assigned to the discharge sustain period of each subfield. The same time division can be allocated.

Meanwhile, as another embodiment of the present invention, the invalid time remaining after the configuration of one frame screen is allocated to the discharge sustain period of each subfield in different ratios, and thus, as shown in FIG. This may cause an increase in luminance of the electrode surface discharge PDP screen.

As described above, the driving method of the three-electrode surface discharge PDP according to the present invention is 1: 2: 8: 16 for each subfield when gradation is implemented according to the ADS subfield method. Each of the discharge sustain periods proportional to is assigned, so that the invalid time remaining after the construction of the one-frame screen for a predetermined time is divided into the discharge sustain periods of each subfield affecting the screen brightness of the three-electrode surface discharge PDP. There is an effect that can greatly increase the brightness of the electrode surface discharge PDP screen.

1 is a block diagram showing a simplified configuration of a typical three-electrode surface discharge plasma display panel and a driving device thereof;

FIG. 2 is a cross-sectional view of one cell of the three-electrode surface discharge plasma display panel shown in FIG. 1, but the front substrate is rotated by 90 °;

3 is a timing diagram of some voltage waveforms applied to each electrode according to the prior art ADS subfield method;

4 is a detailed configuration diagram of one frame when implementing 256 gray scales according to the prior art ADS subfield method;

5 is a detailed configuration diagram of one frame when implementing 256 gray scales according to a driving method of a three-electrode surface discharge plasma display panel according to an embodiment of the present invention.

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

10: 3-electrode surface discharge plasma display panel

20: Y drive unit 30: X drive unit

40: address driver 50: controller

Claims (2)

In order to display a 2 ^× gray scale image on a three-electrode surface discharge plasma display panel (hereinafter referred to as a three-electrode surface discharge PDP), the discharge sustain periods are respectively set to 2 ⁰ : 2 ¹ : 2 ² : 2 ³ :. In the driving method of a three-electrode surface discharge PDP constituting one frame screen by selecting and combining X sub-field screens allocated at a rate of 2 ^{χ −1 in} units of cells for a predetermined time period, The discharge sustain period of each subfield, the screen is 2 ^0: 2 ^1: 2 ^2: 2 ^3: ... : A three-electrode surface discharge, characterized by allocating a part or all of the dead time remaining after the construction of one frame screen by allocating at a ratio of 2 ^{χ −1} to each of the discharge sustain periods of the X subfields. How to drive PDP. The method of claim 1, And a part or all of the invalid time remaining after the configuration of the one-frame screen is allocated to the discharge sustain periods of the X subfields by the same time, respectively.

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