KR100599642B1 - Panel driving method and apparatus with address-sustain mixed interval - Google Patents

Abstract

The present invention relates to a display device that displays an image by sequentially performing an address period and a sustain period like a plasma display panel (PDP), and divides pixels of the panel into a plurality of groups including a first group and a second group. And a panel driving device for driving pixels belonging to each group, the frame being divided into a plurality of subfields including a first subfield and a second subfield continuous to the first subfield, An image signal processor for converting an image signal input from the outside into grayscale data such that the weight of the first subfield for the group is equal to the weight of the second subfield for the second group, and output signals of the image signal processor A subfield data generator that generates subfield data by inputting a voltage corresponding to an output signal of the subfield data generator; It comprises the address data driver, and the scan, sustain electrode driver for applying a voltage corresponding to the output signal of the subfield data generator unit to scan electrodes and sustain electrodes of the panel to be applied to the address electrode of the panel.

Plasma display panel, image processing unit, conversion unit, gradation representation data group, image signal

Description

A panel driving method and apparatus therefor operating in a mixture of an address period and a sustain period {PANEL DRIVING METHOD AND APPARATUS WITH ADDRESS-SUSTAIN MIXED INTERVAL}

1 is a partial perspective view of an AC plasma display panel.

2 illustrates an electrode arrangement diagram of a plasma display panel.

3 illustrates a conventional driving method for driving a plasma display panel.

4 is a block diagram schematically illustrating an apparatus for driving a plasma display panel according to an embodiment of the present invention.

5 illustrates a driving method according to an embodiment of the present invention.

The present invention relates to a method of driving an image display device, and more particularly, to a method of driving a display device in which an address period and a sustain period are sequentially performed, such as a plasma display panel (PDP). will be.

A plasma display panel is a flat display device that displays characters or images using plasma generated by gas discharge, and tens to millions or more pixels are arranged in a matrix form according to their size. The plasma display panel is classified into a direct current type (DC type) and an alternating current type (AC type) according to the shape of the driving voltage waveform applied and the structure of the discharge cell.

1 is a partial perspective view of an AC plasma display panel.

As shown in FIG. 1, the scan electrode 4 and the sustain electrode 5 covered with the dielectric layer 2 and the protective film 3 are formed in parallel on the first glass substrate 1. A plurality of address electrodes 8 covered with the insulator layer 7 are provided on the second glass substrate 6. The partition 9 is formed on the insulator layer 7 between the address electrodes 8 in parallel with the address electrode 8. In addition, the phosphor 10 is formed on the surface of the insulator layer 7 and on both side surfaces of the partition wall 9. The first glass substrate 1 and the second glass substrate 6 have a discharge space 11 therebetween so that the scan electrode 4 and the address electrode 8 and the sustain electrode 5 and the address electrode 8 are orthogonal to each other. They are arranged to face each other. The discharge space at the intersection of the address electrode 8 and the paired scan electrode 4 and the sustain electrode 5 forms a discharge cell 12.

This structure causes a discharge to generate wall charges in order to select a pixel between the address electrode 8 and the scan electrode 4, and then to display an image between the scan electrode 4 and the sustain electrode 5. The discharge is repeated for a certain time. The partition 9 serves to form a discharge space and to prevent cross talk of neighboring pixels by blocking light generated during discharge. Plasma display panels, which are currently commercialized, generate a discharge in each pixel, and excite the fluorescent material coated on the inner wall of the pixel with ultraviolet rays generated by the discharge to realize a desired color.

2 shows an electrode arrangement diagram of the plasma display panel.

As shown in Fig. 2, the PDP electrode has a matrix configuration of m X n. Specifically, the address electrodes A1 to Am are arranged in the column direction, and the scan electrodes Y1 to n rows in the row direction. Yn) and sustain electrodes X1 to Xn are arranged in a zigzag. The discharge cell 12 shown in FIG. 2 corresponds to the discharge cell 12 shown in FIG.

The plasma display panel illustrated in FIGS. 1 and 2 should be able to express a halftone in order to perform as a color display. In the current half gray scale implementation method, a half gray scale is divided into a plurality of subfields, and time division control is performed to implement half gray scale.

3 illustrates a conventional driving method for driving a plasma display panel.

This is an ADS driving method mainly used in the present plasma display panel, and adopts a method of implementing gradation by the field-subfield structure and driving the address period and the sustain period separately in time. That is, after the addressing operation from the first scan electrode to the last scan electrode is completed, the sustain operation is performed on all the pixels at the same time.

In this driving method, after the addressing operation is performed on one scan electrode, the sustain discharge operation in the scan line is performed only after the addressing operation of the last scan line is completed. Therefore, there is a problem that a significant time gap occurs before the sustain discharge operation is performed in the cell where the addressing operation has occurred, and thus the sustain discharge operation becomes unstable.

SUMMARY OF THE INVENTION The present invention has been made in an effort to provide an electrode driving method of a flat panel display device in which smooth sustain discharge may occur by minimizing a time gap between an address period and a sustain period.

Another object of the present invention is to provide an electrode driving apparatus and a driving method of a flat panel display device capable of preventing an increase in the capacity of a logic processing unit to generate grayscale data corresponding to a plurality of groups of pixels of a display panel.

In order to achieve the above object, a panel driving apparatus according to an aspect of the present invention divides pixels of a panel into a plurality of groups including a first group and a second group and divides one frame into a first subfield and the first A panel driving apparatus for dividing a plurality of subfields including a second subfield continuous to a subfield, and for driving pixels belonging to each group, the panel driving apparatus comprising: a weight of the first subfield for the first group and the weight; An image signal processor for generating an image signal input from the outside as grayscale data corresponding to each group such that weights of the second subfields for the second group are the same; A subfield data generator configured to input output signals of the image signal processor to generate subfield data; An address electrode driver for applying a voltage corresponding to an output signal of the subfield data generator to an address electrode of the panel; And a scan and sustain electrode driver configured to apply a voltage corresponding to an output signal of the subfield data generator to the scan and sustain electrodes of the panel.

In the panel driving apparatus according to an aspect of the present invention, the image signal processor is configured to generate a gray level data for the first group from the gray level expression data group and the first converter from the gray level data for the first group. And a second converter generating grayscale data for the two groups, and combining the signal output from the first converter and the signal output from the second converter to output to the subfield data generator.

In the panel driving apparatus according to an aspect of the present invention, the panel driving apparatus inputs the image signal to correct a gamma value according to the characteristics of the panel, and performs a diffusion process on the surrounding pixels to diffuse the display error to the image. The apparatus further includes a gamma correction and error check unit output to the signal processor.

In the panel driving apparatus according to an aspect of the present invention, the second converter includes a conversion matrix, converts an output signal from the first converter according to the conversion matrix, and a gray level corresponding to the second group. Output the data.

In the panel driving apparatus according to an aspect of the present invention, groups of pixels included in the panel are classified for each of the scan electrodes.

In the panel driving apparatus according to an aspect of the present invention, the subfield data driver sequentially performs an address operation and a sustain discharge operation on the pixels belonging to the respective groups, and performs an address operation on the pixels of any one group. During the operation, the other pixels are in the dormant state, and while the sustain discharge operation is performed on the other group of pixels, the pixels of the group where the address operation is already performed are sustained and discharged.
In the panel driving apparatus according to an aspect of the present invention, the first subfield and the second subfield have the same weight.

According to an aspect of the present invention, there is provided a method of driving a panel, comprising: dividing pixels of a panel into a plurality of groups including a first group and a second group, wherein a frame is continuous to a first subfield and the first subfield. A panel driving method comprising dividing into a plurality of subfields including two subfields, wherein each address period and a sustain discharge period for each of the plurality of groups are assigned to each subfield, the panel driving method comprising: a first method for the first group; A first step of converting the input image signal into grayscale data such that the weight of the subfield is equal to the weight of the second subfield for the second group; A second step of generating subfield data by inputting the converted grayscale data; And a third step of applying a voltage corresponding to the subfield data to an electrode of the panel.

A panel driving method according to another aspect of the present invention is a panel driving method for dividing pixels of a panel into a plurality of groups, addressing and sustaining discharge pixels of each group, wherein one subfield is any one of the plurality of groups. A first addressing period for addressing the first; A first sustain period applying a sustain pulse to the plurality of groups of scan electrodes; A second addressing period for addressing another group of the plurality of groups; And a second sustain period for applying a sustain pulse to the scan electrodes of the plurality of groups, and the order of the groups addressed in the one subfield and the other subfield is changed.

Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.

In the following description, an embodiment of the present invention is optimally applied to a plasma display panel driving method. However, the concept of the present invention is not limited to a specific display device. It can be applied to all display devices which are performed sequentially to display an image.

4 is a block diagram schematically illustrating an apparatus for driving a plasma display panel according to an embodiment of the present invention.

The driving apparatus of the plasma display panel 600 according to an exemplary embodiment of the present invention includes a gamma correction and error checker 100, an image signal processor 200, a subfield data generator 300, and an address data driver 400. And a scan and sustain electrode driver 500.

The gamma correction and error checking unit 100 corrects the gamma value of the input image signal according to the characteristics of the plasma display panel 600, and outputs the display error by performing diffusion processing on the surrounding pixels.

The image signal processor 200 may convert the output signal of the first converter 210 and the first converter 210 to convert the signal output from the gamma correction and error checker 100 into grayscale data corresponding to one group. The second converter 220 converts the grayscale data of the group. Specifically, the first converter 210 includes a gradation representation data group corresponding to one group and converts image data from outside into appropriate gradation representation data by the gradation representation data group. The second converter 220 includes a transformation matrix and secondarily converts a signal output from the first converter 210 into gray level representation data of another group.

The subfield data generator 300 generates and outputs subfield data from an output signal of the image signal processor 200. The address data driver 400 applies a voltage corresponding to the subfield data generator 300 to the address electrodes A1, A2,.

The scan and sustain electrode driver 500 generates a scan pulse and a sustain pulse corresponding to the subfield data generator 300 to generate the scan electrodes X1, X2, .. Xn and sustain electrodes Y1, Y2 of each group. , ..., Yn).

According to an embodiment of the present invention, the scan electrodes of the panel 600 are divided into a plurality of groups, and the scan and sustain electrode driver 500 includes a plurality of driving circuits 510 for driving the scan electrodes belonging to each group. , 520, ..., 5n0).

Hereinafter, a driving method of the plasma display panel according to an embodiment of the present invention will be described in detail.

5 illustrates a driving method according to an embodiment of the present invention.

The driving method according to an embodiment of the present invention represents an image using a plurality of frames, and each frame includes four subfields. The plurality of scan electrodes are divided into two groups to perform the address operation and the sustain discharge operation.

In FIG. 5, a scan electrode is divided into two groups G1 and G2 for convenience of description, and one frame includes four subfields. However, the essence of the present invention is limited to the number of such groups and subfields. It will be apparent to those skilled in the art.

According to an embodiment of the present invention, each subfield may include a reset period R, a first address period A1, a first sustain discharge period S1, a second address period A2, and a second sustain discharge period. (S2).

The reset section R initializes the wall charge state of the pixel by applying a reset pulse to the scan lines of all the groups G1 and G2. As another example, instead of performing the reset period for all the groups G1 and G2 simultaneously, the reset period may be separately performed for each group.

The first and second address periods A1 and A2 are walled to cells (addressed cells) that are turned on by selecting cells that are not turned on and cells that are not turned on among cells belonging to the first group G1 and the second group G2. This is the period during which charge accumulation operations are performed. The other pixels are in the idle state during the address periods A1 and A2.

The first and second sustain discharge sections S1 and S2 are periods in which sustain pulses are alternately applied to the scan electrodes Y1-Yn and the sustain electrodes X1-Xn. In this period, sustain discharge is generated and an image is displayed.

In FIG. 5, the number of sustain pulses in the first and second sustain discharge sections S1 and S2 is a number suitable for representing an image of a corresponding gray scale. That is, the number of sustain pulses in the first and second subfields is suitable for representing the first grayscale image, and the number of sustain pulses in the third and fourth subfields represents the fourth grayscale image. Suitable number.

According to an embodiment of the present invention, the addressing order in the first group G1 and the second group G2 is alternately converted for each subfield. That is, in the first subfield, the first group G1 performs the addressing operation first, and in the second subfield, the second group G2 performs the addressing operation first. In this case, two sustain discharge operations are performed in the corresponding subfield in the group performing the addressing operation first, and one sustain discharge operation is performed in the group performing the addressing operation.

Accordingly, in the case of the first subfield, the first group G1 is performed twice in the maintenance mode corresponding to the first grayscale to display an image corresponding to the second grayscale, and the second group G2 is the first group. Since the sustain discharge corresponding to the gray scale is performed once, an image corresponding to the first gray scale is represented.

A method of expressing gray scales according to an embodiment of the present invention will be described.

In FIG. 5, when displaying an image corresponding to the first gray level, the first group G1 activates the second subfield, and the second group G2 activates the first subfield.

That is, if the activated case is '1' and the deactivated case is '0', the gray level data of the first group G1 for displaying the first gray level is [0 1 0 0] and the second group G1 is used. Gray level data becomes [1 0 0 0].

In addition, when displaying an image corresponding to the second gray level, the first group G1 activates the first subfield, and the second group G2 activates the second subfield. In this case, the gradation data of the first group G1 for representing the second gradation is [1 0 0 0], and the gradation data of the second group G2 is [0 1 0 0].

Similarly, the gradation data of the first group G1 for representing the third gradation is [1 1 0 0], and the gradation data of the second group G2 is [1 1 0 0].

In this manner, the first to third gray levels may be expressed by combining the first and second subfields. In this case, the grayscale data applied to the first group G1 and the second group G2 has a kind of correlation. When the data of the first row and the second row of the grayscale data of the first group G1 are interchanged, It can be seen that it is the same as the grayscale data of the second group G2.

Similarly, the third to seventh grayscales may be expressed by a combination of the third and fourth subfields. In this case, when the data of the third row and the fourth row of the grayscale data of the first group G1 are interchanged with each other, It becomes grayscale data of two groups G2.

Therefore, by setting the addressing order of each group differently for each subfield, the grayscale data of another group can be generated only by the grayscale data of one group.

That is, when the first converter 210 includes the gradation representation data group of the first group G1 and converts the image signal into gradation data corresponding to the first group G1, the second converter 220 The gray level data corresponding to the second group G2 can be generated using the correlation between the first group G1 and the second group G2. Accordingly, by generating the degree data corresponding to the plurality of groups with one gray level expression data group, it is possible to reduce the increase in the capacity of the logic processing unit and to reduce the production cost.

Although the embodiments to which the present invention has been optimally applied have been described above, it is apparent to those skilled in the art that the concept of the present invention is not limited to the above embodiments, and various other embodiments can be formed using the present invention as it is.

According to the present invention, it is possible to minimize the time gap between the address period and the sustain period so that smooth sustain discharge can occur.

In addition, since grayscale data corresponding to a plurality of groups of pixels of the display panel may be generated as one grayscale expression data group, the cost of the display device may be reduced by reducing the load of the logic processing unit.

Claims (14)

The pixels of the panel are divided into a plurality of groups including a first group and a second group, and one frame is divided into a plurality of subfields including a first subfield and a second subfield continuous to the first subfield. In the panel driving apparatus for driving the pixels belonging to each group, The image signal input from the outside is generated as gray data corresponding to each of the plurality of groups such that the weights of the first subfields for the first group and the weights of the second subfields for the second group are the same. An image signal processor; A subfield data generator configured to input output signals of the image signal processor to generate subfield data; An address electrode driver for applying a voltage corresponding to an output signal of the subfield data generator to an address electrode of the panel; And A scan and sustain electrode driver for applying a voltage corresponding to an output signal of the subfield data generator to the scan and sustain electrodes of the panel Panel driving device comprising a. The method of claim 1, The image signal processing unit may include a first converter for generating grayscale data for the first group as a gray level representation data group and a second converter for generating grayscale data for the second group from grayscale data for the first group. Including, A panel driving device for combining the signal output from the first converter and the signal output from the second converter to output to the subfield data generator. The method of claim 1, The panel driving apparatus further includes a gamma correction and error checking unit configured to input the image signal to correct a gamma value according to the characteristics of the panel, and to perform a diffusion process on neighboring pixels to output the display error to the image signal processor. Panel drive. The method of claim 2, And the second converter includes a conversion matrix, converts an output signal from the first converter according to the conversion matrix, and outputs grayscale data corresponding to the second group. The method of claim 1, The group of pixels included in the panel is divided by the scan electrodes. The method of claim 1, The subfield data generation unit sequentially performs an address operation and a sustain discharge operation on the pixels belonging to the respective groups, and causes the other pixels to be in a dormant state while performing an address operation on one group of pixels. A panel driving apparatus for causing a group of pixels which have already been subjected to an address operation to sustain discharge while performing a sustain discharge operation on another group of pixels. The pixels of the panel are divided into a plurality of groups including a first group and a second group, and one frame is divided into a plurality of subfields including a first subfield and a second subfield continuous to the first subfield. And the respective address periods and sustain discharge periods for the plurality of groups are assigned to the respective subfields. A first step of converting an input image signal into grayscale data such that a weight of a first subfield for the first group is equal to a weight of a second subfield for the second group; A second step of generating subfield data by inputting the converted grayscale data; And A third step of applying a voltage corresponding to the subfield data to an electrode of the panel Panel driving method comprising a. The method of claim 7, wherein The plurality of pixel groups included in the panel are classified for each scan electrode. The method of claim 7, wherein In the third step, the address operation and the sustain discharge operation are sequentially performed on the pixels belonging to each group, and the other pixels are in the idle state while the address operation is performed on the pixels of one group. And applying a voltage to the panel such that the pixels of the group where the address operation is already performed are sustain discharged while the sustain discharge operation is performed on the other group of pixels. In the panel driving method for dividing the pixels of the panel into a plurality of groups, addressing and sustain discharge the pixels belonging to each group, One subfield A first addressing period for addressing any one of the plurality of groups; A first sustain period applying a sustain pulse to the plurality of groups of scan electrodes; A second addressing period for addressing another group of the plurality of groups; And A second sustain period for applying a sustain pulse to the scan electrodes of the plurality of groups; Including, And a group of groups addressed in the one subfield and the other subfield is changed. The method of claim 10, The subfield further includes a reset period for initializing a wall charge state of a pixel by applying a reset pulse to the plurality of groups of scan electrodes before the first addressing period. The method of claim 7, wherein The first step, Generating gradation data for the first group using a gradation representation data group and generating gradation data corresponding to the second group by converting the gradation data for the first group by a transformation matrix. Driving method. The method according to any one of claims 1 to 6, And the first subfield and the second subfield have the same weight. The method according to any one of claims 7 to 12, The first subfield and the second subfield have the same weight with each other.

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