JP2757795B2 - Plasma display luminance compensation method and plasma display device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a plasma display and, more particularly, to a method for compensating for luminance fluctuation due to a load fluctuation applied to a sustain pulse driving circuit of a memory type plasma display.

[0002]

2. Description of the Related Art Plasma display panels (PDPs)
Has many features such as a thin structure, no flicker, a relatively large screen, a fast response speed, and a self-luminous type that can emit multiple colors by using a phosphor. It is being widely used in the field of related display devices and the field of color image display.

[0003] Depending on the operation method, this PDP has an AC discharge (AC) type in which electrodes are covered with a dielectric and indirectly operates in an AC discharge state, and a PDP in which electrodes are exposed to a discharge space and are directly in a DC discharge state. There is a direct current discharge (PDP) type to be operated. Further, the AC type driving includes a memory type using a memory of a discharge cell and a refresh type not using the memory as a driving method.

Referring to FIG. 13 showing a cross-sectional structure of one display cell of an AC memory type PDP, this PDP comprises a first insulating substrate 39 made of glass, a second insulating substrate 45 also made of glass, a scanning electrode 37, The sustain electrode 40, the data electrode 44, the discharge gas space 38 filled with He, Ne, Xe, or the like or a mixed gas thereof, the discharge gas space 38 is secured, and the barrier 35 that divides the display cell is generated by discharge of the discharge gas. Phosphor 4 that converts ultraviolet light into visible light
2. Insulator 36, insulator 3 covering scan electrode and sustain electrode
6 is provided with a protective film 41 made of magnesium oxide or the like that protects 6 from discharge, and an insulator 42 that covers the data electrodes.

Next, the discharge operation of the selected display cell will be described. A pulse voltage exceeding a discharge threshold, that is, a data pulse, is applied between the scan electrode 37 and the data electrode 44 to start the discharge. The positive and negative charges are attracted to the surfaces of the dielectrics on both sides in accordance with the polarity of the charge, and the charge accumulates. Since the equivalent internal voltage, that is, the wall voltage, due to the accumulation of the charges has the opposite polarity to the voltage of the data pulse, the effective voltage inside the cell decreases as the discharge grows, and the voltage of the data pulse becomes constant. Even if the voltage is held, the discharge cannot be continued and finally stops.

Thereafter, when a sustaining pulse having the same polarity as the wall voltage is applied between the adjacent scanning electrode 37 and the sustaining electrode 40, the wall voltage is superimposed as an effective voltage. Even if the voltage amplitude of the sustain pulse is lower than the voltage of the discharge threshold, the display cell can be internally discharged beyond the threshold.

Accordingly, the discharge can be maintained by continuously applying the sustain pulse between the scan electrode 37 and the sustain electrode 40. This function is the above-mentioned memory function. Further, the discharge can be stopped by applying an erasing pulse, which is a low-voltage pulse voltage having a magnitude and width that neutralizes the wall voltage, to the scan electrode or the sustain electrode.

A PD for dot matrix display in which display cells 34 are arranged on a matrix of j × k rows and columns
Referring to FIG. 14 showing a configuration focusing on the electrode arrangement of P, the PDP 19 shown in FIG. 14 includes scan electrodes Sc1, Sc2,..., Scj and sustain electrodes Su arranged in parallel with each other.
, Suj, and data electrodes D1, D2,... Dk arranged orthogonally to the scan electrodes and the sustain electrodes.
And

Here, if the phosphors 42 are separately applied to three colors of RGB, a PDP capable of color display can be obtained.

The above driving method will be described below. See JP-A-6-186927 for reference.

FIG. 16 is a time chart showing an example of the above-described drive voltage waveform. In correspondence with PDP 19 shown in FIG. 17, a common sustain electrode drive pulse Wu applied to sustain electrodes Su11, Su12,. And scanning electrodes Sc11, Sc12, Sc1m, Sc21, Sc22,
Sc2m, Sc31, Sc32, Sc3m, Sc41,
Scan electrode drive pulses Ws11, Ws12, Ws1m, Ws21, Ws applied to Sc42 and Sc4m, respectively.
22, Ws2m, Ws31, Ws32, Ws3m, Ws
3m, Ws41, Ws42, Ws4m and data electrode D
5 shows a data pulse Wdi applied to i (1 ≦ i ≦ k).

Driving is temporally divided into three periods: a preliminary discharge period Tp, a write discharge period Tw, and a sustain discharge period Ts. The sustain electrode drive pulse Wu is a preliminary discharge pulse Vp.
And sustain pulse Vsu, and scan electrode drive pulse Ws
11, Ws12, Ws1m, Ws21, Ws22, Ws
2m, Ws31, Ws32, Ws3m, Ws3m, Ws
41, Ws42 and Ws4m are common pre-discharge erase pulse Vp, sustain pulse Vss, erase pulse Ve and S
Scan pulses Vw1 applied at sequential timings sequentially applied in the order of c11, Sc12,...
1, Vw12, Vw1m, Vw21, Vw22, Vw2
m, Vw31, Vw32, Vw3m, Vw41, Vw4
2, Vw4m.

The preliminary discharge period Tp is a period for generating active particles for stably generating a write discharge in a subsequent write discharge period, and is forcibly performed by applying a preliminary discharge pulse Vp to all sustain electrodes. All the cells of the PDP are discharged, and the pre-discharge erase pulse Vpe neutralizes the wall charges in the display cells, and ends.

To light the first i-th display cell, the data pulse Vdi is made coincident with the timing of the scanning pulse Vw11 to generate a discharge between the scanning electrode Sc11 corresponding to the scanning pulse Vw11 and the data electrode Di. Let it. When this display cell is not turned on, the data pulse Vdi is not applied.

As described above, in the display cell once lit by the application of the data pulse Vdi, the discharge is repeated between the scan electrode and the sustain electrode by the sustain pulse Vss and the sustain pulse Vsu after this timing, and the lighting is continued. When the sustain erasing pulse Ve is applied to the scan electrode, the discharge stops and the light is turned off.

Since the sustain pulses Vss and Vsu are common to all the scanning lines, the sustain pulses Vss and Vsu are generally constituted by one sustain pulse generating circuit for a plurality of scanning lines. PDP
Is relatively small and the display area of the PDP is usually divided into several parts, and one sustain pulse generating circuit is provided for each of the divided areas, unless the load of the sustain pulses Vss and Vsu is small. Is assigned.

A sustain pulse driving circuit 1 for dividing a display area of a PDP into four and supplying sustain pulses corresponding to each area.
Basic P with 4A-14D and 15A-15D
Referring to FIG. 15 showing an example of the DP driving circuit, the basic PDP driving circuit shown in FIG.
PDP19 and P in addition to A-14D and 15A-15D
Data drivers 11 and 12 for applying data pulses Vdi to the respective data electrodes respectively corresponding to the odd and even data lines of DP19, and the display data D input to the data clock C are divided into odd and even data lines. Distributor 20 for supplying the data Du and Dd to the data drivers 11 and 12, respectively, and a pre-discharge pulse Vp, a pre-discharge erase pulse Vpe and a sustain erase in response to a signal from a timing generator 21 based on a field signal. A pre-discharge pulse driving circuit 23, a pre-discharge erasing pulse driving circuit 22, and a sustain erasing pulse driving circuit 24 for supplying the pulses Ve, respectively, and a scanning driver 13 for generating a scanning pulse in response to the field signal F and the scanning signal S
And a mixer 16 that mixes the sustain pulse, the preliminary discharge erase pulse, the sustain erase pulse, and the scan pulse to generate a scan electrode driving pulse, and a mixer that mixes the sustain pulse and the preliminary discharge pulse to generate a sustain electrode drive pulse. And a vessel 17.

In operation, the sustain discharge in the previous field is stopped by the field signal F, a preliminary discharge is performed, and the corresponding scan electrodes are sequentially driven at each timing of the scan signal S. The display data D is divided into data Du and Dd by the data distributor 20 and supplied to the data drivers 11 and 12, respectively. The data drivers 11 and 12 apply the data pulse V to the data electrodes respectively corresponding to the odd and even data lines shared by them.
Apply di. The display cells to which the write discharge has been performed by this scanning repeat the sustain discharge by the following sustain pulses Vsu and Vss.

[0019]

In such a PDP, for example, of the display cells driven by a pair of scan electrodes Sce and sustain electrodes Sue shown in FIG. There is a problem that the brightness is different. That is, when the number of lightings in one row is small, the brightness of the lighting display cell is high, and when the number of lightings in one row is large, the brightness of the lighting display cell is low.

A PDP having a structure as shown in FIG.
In, for example, sustain pulse driving circuits 14A and 15A
Are different in the number of lighting of the display cells in the area shared by the display cells, the output pulse impedance of the sustain pulse driving circuits 14A and 15A or the impedance of the scan electrode and the sustain electrode of the PDP causes a difference in the sustain pulse waveform and amplitude applied to each display cell. Occurs, and the light emission output, that is, the luminance, of the display cells in the above-mentioned region differs depending on the number of lighted display cells of the display cells in the region.

That is, when the number of lightings in a region driven by the same drive circuit, the scanning electrode, and the sustain electrode pair is small, the brightness is high, and conversely, when the number of lightings is large, the brightness is low.

As a result, display of correct luminance is not performed, and crosstalk occurs in the horizontal direction. In addition, in the case of multi-gradation color display, there is a problem that gradation and chromaticity are not accurately reproduced, resulting in a display that is significantly deteriorated.

An object of the present invention is to solve the above-mentioned problems and to provide a PDP in which luminance fluctuations due to the number of lighting display cells are reduced.

[0024]

According to the present invention, there is provided a brightness compensation method for a plasma display, comprising: a scan electrode group comprising a plurality of scan electrodes corresponding to scan lines of a display cell formed on the same plane; Of a plasma display including at least a sustain electrode group consisting of a plurality of sustain electrodes for use and a data electrode group consisting of a plurality of data electrodes for writing data that are orthogonal to the scan electrode group and the sustain electrode group and are driven according to display data. In the method, a write discharge period for selecting a display cell and a sustain discharge period for sustaining light emission of the selected display cell are driven separately, and each correction unit display row including at least one set of scan electrodes and sustain electrodes is driven. The distribution of the display data is detected and the correction unit display row is calculated by a predetermined luminance variation coefficient corresponding to the distribution of the display data. Obtaining the number of sustain discharges to obtain a desired brightness, the correction unit display each row, the number of sustain discharges, characterized in that the stop sustain discharge at the end of completion.

Alternatively, a scan electrode group consisting of a plurality of scan electrodes corresponding to scan lines of a display cell formed on the same plane, a sustain electrode group consisting of a plurality of sustain electrodes for sustaining discharge of the display cell, and the scan electrode In a method for driving a plasma display, comprising at least a data electrode group consisting of a plurality of data electrodes for data writing, which is orthogonal to the group and the sustain electrode group and is driven according to display data, a write discharge period for selecting a display cell and the selected discharge period. The sustain discharge period for sustaining light emission of the display cell is driven separately, and
The scan electrode group and the sustain electrode group are divided by a plurality of sustain pulse drive circuits and sustain discharge drive is performed, and the distribution of display data of display cells driven by each sustain pulse drive circuit is detected, and the distribution of display data is detected. The number of sustain discharges for obtaining a desired luminance is calculated for each sustain pulse drive circuit by calculating using a predetermined luminance variation coefficient, and the sustain discharge is stopped after the predetermined number of sustain discharges is completed for each sustain pulse drive circuit. It is characterized by the following.

Alternatively, a scan electrode group consisting of a plurality of scan electrodes corresponding to scan lines of a display cell formed on the same plane, a sustain electrode group consisting of a plurality of sustain electrodes for sustaining discharge of the display cell, and the scan electrode In a method for driving a plasma display, comprising at least a data electrode group consisting of a plurality of data electrodes for data writing, which is orthogonal to the group and the sustain electrode group and is driven in accordance with display data, a write discharge period for selecting a display cell, The sustain electrodes are driven separately with a sustain discharge period for sustaining light emission, and the scan electrode group and the sustain electrode group are divided by a plurality of sustain pulse drive circuits to perform sustain discharge drive, and are driven by the respective sustain pulse drive circuits. The distribution of the display data of the display cells to be detected, and a correction comprising at least one pair of the scanning electrode and the sustain electrode. A distribution of display data for each display row is detected, and a calculation is performed based on a predetermined luminance variation coefficient from the distribution of display data for each of the sustain pulse driving circuits and for each of the correction unit display rows, and the correction unit for each correction unit display row is calculated. The sustain discharge is stopped after the predetermined number of sustain discharges is completed for each correction unit display row.

Alternatively, the sustain discharge is stopped by applying an erase pulse to the scan electrode or the sustain electrode.

Alternatively, the sustaining discharge is stopped by applying an erasing pulse to the scan electrode or the sustaining electrode, and all the sustaining discharges in the display region of the sustaining pulse driving circuit are stopped for each of the sustaining pulse driving circuits. Thereafter, the sustain pulse of the sustain pulse driving circuit is stopped.

Alternatively, the sustain discharge is stopped by stopping one or both of the sustain pulse to the scan electrode and the sustain pulse to the sustain electrode.

Alternatively, the sustain discharge is stopped by applying a sustain pulse having the same phase as the sustain pulse to the sustain electrode to the scan electrode, or applying a sustain pulse having the same phase as the sustain pulse to the scan electrode to the sustain electrode. It is characterized by performing by applying.

In the plasma display device of the present invention, a scan electrode group consisting of a plurality of scan electrodes corresponding to the scan lines of the display cells formed on the same plane and a sustain electrode consisting of a plurality of sustain electrodes for maintaining the discharge of the display cells. A plasma display comprising at least a data electrode group consisting of a plurality of data electrodes for data writing driven in accordance with display data orthogonal to the electrode group and the scan electrode group and the sustain electrode group, and at least one set of scan electrodes. A detection circuit for detecting a distribution of display data for each correction unit display row, which includes a sustain electrode; and a desired luminance for each of the correction unit display rows calculated by a predetermined luminance variation coefficient corresponding to the distribution of the display data. An arithmetic circuit for calculating the number of sustain discharges to obtain
An erase pulse drive circuit or a sustain pulse stop circuit having a function of stopping the sustain discharge after the number of sustain discharges ends for each correction unit display row based on the number of sustain discharges obtained by the arithmetic circuit. It is characterized by.

Alternatively, a scan electrode group consisting of a plurality of scan electrodes corresponding to scan lines of a display cell formed on the same plane, a sustain electrode group consisting of a plurality of sustain electrodes for sustaining discharge of the display cell, and the scan electrode A plasma display comprising at least a data electrode group composed of a plurality of data electrodes for data writing that is orthogonal to the group and the sustain electrode group and is driven in accordance with display data, wherein the sustain electrode group is divided into the scan electrode group and the sustain electrode group. A plurality of sustain pulse driving circuits to be driven, and a detection circuit that detects a distribution of display data of display cells driven by each of the sustain pulse driving circuits,
An arithmetic circuit for calculating the number of sustain discharges for obtaining a desired luminance for each sustain pulse driving circuit by performing arithmetic operation using a predetermined luminance variation coefficient corresponding to the display data, and based on the number of sustain discharges obtained by the arithmetic circuit. An erasing pulse driving circuit or a sustain pulse stopping circuit having a function of stopping the sustain discharge after a predetermined number of sustain discharges is completed for each sustain pulse driving circuit.

Alternatively, a scan electrode group consisting of a plurality of scan electrodes corresponding to scan lines of a display cell formed on the same plane, a sustain electrode group consisting of a plurality of sustain electrodes for sustaining discharge of the display cell, and the scan electrode A plasma display comprising at least a data electrode group composed of a plurality of data electrodes for data writing that is orthogonal to the group and the sustain electrode group and is driven in accordance with display data, wherein the sustain electrode group is divided into the scan electrode group and the sustain electrode group. A plurality of sustain pulse driving circuits to be driven, a first detection circuit for detecting a distribution of display data of display cells driven by each of the sustain pulse driving circuits, and a correction comprising at least one set of scan electrodes and sustain electrodes A second detection circuit for detecting a distribution of display data for each unit display row, and a table for each of the sustain pulse drive circuits and for each of the correction unit display rows; An arithmetic circuit for calculating the number of sustain discharges for each correction unit display row by calculating based on a predetermined luminance variation coefficient from the distribution of data, and for each correction unit display row based on the number of sustain discharges obtained by the arithmetic circuit. An erase pulse driving circuit or a sustain pulse stop circuit having a function of stopping the sustain discharge after a predetermined number of sustain discharges is completed is provided.

[0034]

Next, embodiments of the present invention will be described with reference to the drawings. FIG. 1 is a block diagram showing a circuit of a first embodiment of a brightness compensation circuit for realizing the plasma display according to the present invention. Referring to FIG. Counter 1 for counting numbers
A memory 4 for storing a count value D11 of the counter 1,
A counter 2 for counting the number of scans, a counter 3 for calculating the number of times of maintenance, a count value S11 of the counter 2 and a counter 3
A selector 5 for selecting one of the count values S12, a memory 6 for storing sustain discharge stop timing data,
A comparator 7 compares the output data MD1 to MD of the memory 6 with the measurement value S12 of the counter 3 and outputs the maintenance stop signals SD1 to SD.

Referring to FIG. 2 which is a block diagram showing the configuration of a drive circuit of a PDP having the luminance compensation circuit of the present embodiment,
The PDP 9 shown in FIG.
And a sustain pulse driving circuit 15 for supplying a sustain pulse;
The data distributor 20, the scan driver 13, the timing generator 21, the sustain erase pulse drive circuit 24, the preliminary discharge pulse drive circuit 23, the preliminary discharge erase pulse drive circuit 22, and the mixture of the sustain pulse and the preliminary discharge pulse A mixer 17 for generating a sustain electrode driving pulse; a mixer 16 for mixing a sustain pulse, a scan pulse and a sustain erase pulse to generate and supply a scan electrode drive pulse, respectively; Sustain driver 1 that receives sustain stop signals SD1 to j from luminance compensation circuit 18 and generates sustain pulses
4 is provided.

The operation will be described with reference to FIGS. 1 and 2 and FIG. 3 which shows a driving time chart of the driving circuit of this embodiment. The counter 1 is reset in response to the supply of the field signal F and the scanning signal S, and the scanning is performed. The number of display data D for each line is counted, and a count value D11 is output. Counter 2
Counts the scanning signal S and supplies a signal S11 to the selector 7. The counter 3 is reset in response to the sustain start signal SS, counts the sustain period signal SP, and supplies the count value S12 to the selector 5 and the comparator 7. The selector 5 receives the signal S1
1 and the signal S12 are selected, and the address instruction signal A1 is supplied to the memories 4 and 6. In the selection, the count value S11 is selected in the write discharge period Tw in which the display data is supplied and the data pulse Vdi is output, and the count value S12 is selected in the sustain discharge period Ts. In the writing discharge period Tw, the storage value of the count value D11 is stored in the memory 4 as data for each scanning line, with the storage position specified according to the address instruction signal A1. In the sustain discharge period Ts, the number of display data of all scan lines is read out from the memory 4 as the signal D12 every sustain period, and supplied to the memory 6. The memory 6 stores data indicating the number of sustain discharges for obtaining a desired luminance in consideration of the relationship of the ratio of the luminance variation depending on the number of display data, and is instructed by the signal D12 to indicate the number of sustain discharges. The signals MD1 to MDj are supplied to the comparator 7. The comparator 7 outputs the signal M
D1 to j are compared with the signal S12, and when the number of sustain discharges reaches the number of sustain discharges indicated by the signals MD1 to j, the sustain stop signals SD1 to SD1
j is output and supplied to the sustain driver 14.

Referring to FIG. 3, when the sustain pulse of each scan line stops, the sustain discharge is interrupted. Thereafter, a common sustain erase pulse Ve is applied to all the scanning lines, and the process ends. As described above, since the number of sustain discharges is independently controlled for each scanning line and luminance compensation is performed, accurate luminance compensation can be performed over the entire display, and a favorable display state can be realized. Incidentally, in this embodiment, when all the display cells of the corresponding scanning line are turned on, 400 sustain discharge pulses are applied in one frame time. However, when 50% of the cells are turned on, the sustain discharge pulse is turned on 370 times. 10% cells
In this case, 300 pulses were applied.

In this embodiment, the correction unit display lines are provided one by one. However, for example, two or more lines may be collectively controlled as the correction unit display lines. In this case, the control circuit can be somewhat simplified. In particular, in a PDP having a large display capacity, substantial improvement in the display state can be realized even when the correction unit display rows are appropriately set to a plurality of rows. The use of a plurality of correction unit display lines can be applied to all the embodiments described later.

It is not always necessary to detect the display data for all the display cells. Depending on the application, display data of display cells which are discrete every other cell is detected and controlled to simplify the detection circuit. You can try it. Such a method can also be applied in the embodiments described later.

Further, the correction unit display rows for detecting the display data may be set discretely, and the intervening rows may be further interpolated by using interpolation values from the upper and lower display data to further simplify the circuit. This method can also be applied to the embodiments described below.

Next, a second embodiment of the present invention will be described. Referring to FIG. 4 which is a block diagram showing a circuit of a second embodiment of a brightness compensation circuit for realizing the plasma display of the present invention, the brightness compensation circuit of the present embodiment is different from the first embodiment in the sustain discharge. Scan electrodes and sustain electrodes instead of the memory 6 for storing the timing data for stopping the scanning.
The memory 10 stores timing data corresponding to the sustain discharge stop for each of the divided instruction blocks A to D.

Referring to FIG. 4 which is a block diagram showing a configuration of a driving circuit of a PDP having the luminance compensation circuit of this embodiment,
PDP 19 similar to the basic PDP drive circuit shown in FIG.
, The display area of the data drivers 11 and 12 and the display area of the PDP 19 are divided into four,
Pulse driving circuit 1 for supplying sustain pulses corresponding to .about.D
4A to 14D, 15A to 15D, and the data distributor 20
A scan driver 13, a timing generator 21, a sustain erase pulse drive circuit 24, a pre-discharge pulse drive circuit 23, a pre-discharge erase pulse drive circuit 22, and a sustain pulse A mixer 17 for generating a driving pulse; and a sustain pulse, a scanning pulse and a sustain erasing pulse are mixed to generate a scanning electrode driving pulse.
A luminance compensating circuit 18 in addition to the mixer 16 to be supplied;
Sustain drivers 14A to 14D that receive sustain stop signals SD1 to SD4 from luminance compensation circuit 18 and generate sustain pulses.

The operation will be described with reference to FIGS. 4 and 5, and FIG. 6 showing a drive time chart of the drive circuit of this embodiment. The difference from the first embodiment will be described so as not to make the description redundant. The memory 10 determines the desired luminance in consideration of the relationship of the ratio of the luminance variation depending on the number of display data of the block for each sustain pulse drive circuit. Data indicating the number of sustain discharges to be obtained is stored, and instructed by signal D12, signals MD1 to MD4 indicating the number of sustain discharges are supplied to comparators 7A to 7D. Comparators 7A to 7D output signals MD.
The signals S1 to S4 are compared with the signal S12.
Is output to the sustain drivers 14A to 14D.

Referring to FIG. 6, the sustain discharge of each sustain pulse driving circuit is interrupted when the sustain pulse stops, and thereafter, the sustain erase pulse Ve common to all scan lines is applied and the sustain discharge ends.

In this system, luminance compensation is performed by the number of display data for each sustain pulse drive circuit. Although the compensation accuracy is relatively coarse, it is possible to easily perform the control such as the stop of the sustain discharge.

Next, a third embodiment of the present invention will be described. Referring to FIG. 7 which is a block diagram showing a circuit of a third embodiment of a brightness compensation circuit for realizing the plasma display of the present invention, the brightness compensation circuit of this embodiment counts the number of display data D for each scanning line. Counter 25, a memory 27 for storing the count value D21 of the counter 25, a counter 25 for counting the number of display data supplied for each of the sustain blocks A to D, and a memory 28 for storing the count value of the counter 25. And a counter 2 for counting the number of scans, a counter 3 for counting the number of times of maintenance, and a count value S2 of the counter 2
1, a selector 5 for selecting either one of the count value S22 of the counter 3 and a memory 29 for storing sustain discharge stop timing data.
And a comparator 30 that compares the count value S22 of the above and outputs a maintenance stop signal.

Referring to FIG. 8 which is a block diagram showing a configuration of a driving circuit of a PDP having the luminance compensation circuit of this embodiment,
PDP 19 similar to the basic PDP drive circuit shown in FIG.
, The display area of the data drivers 11 and 12 and the display area of the PDP 19 are divided into four,
Pulse driving circuit 1 for supplying sustain pulses corresponding to .about.D
4A to 14D, 15A to 15D, and the data distributor 20
A scan driver 13, a timing generator 21, a pre-discharge pulse driving circuit 23, a pre-discharge erasing pulse driving circuit 22, and a mixer 17 for mixing a sustain pulse and a pre-discharge pulse to generate a sustain electrode driving pulse. In addition to the above, a luminance compensating circuit 31, an erasing driver 32 that receives a sustain stop signal ED from the luminance compensating circuit 31 and generates a sustain erasing pulse, and mixes a sustain pulse, a scanning pulse, and a sustain erasing pulse to drive a scan electrode And a mixer 16 for generating and supplying pulses.

The operation will be described with reference to FIGS. 7 and 8 and FIG. 9 showing a driving time chart of the driving circuit of this embodiment. The counter 25 is reset in response to the scanning signal S, and the display data D is reset for each scanning line. Is counted by the clock C synchronized with the display data, and a count value D21 is output.
The counter 26 is reset in response to the supply of the field signal F, and each of the sustain pulse driving circuits 14A to 14D, 1
The display data supplied to each of the shared blocks 5A to 15D is counted based on the count value D21 for each scan line, and the count value D
22 is output. In this case, since the PDP display area is divided into four sustaining blocks A to D as described above, the number of scanning lines corresponding to the shared blocks of each pair of sustaining pulse drive circuits 14A to 14D and 15A to 15D, that is, the number of block lines Is 1/4 of the total number of scanning lines. Counter 2
Supplies the signal S21 to the counter 25 and the selector 5 in order to count the scanning signals S and to classify them for each block line number. The counter 3 is reset in response to the sustain start signal SS, counts the sustain period signal SP, and supplies the count value S22 to the selector 5 and the comparator 30. The selector 5 selects either the signal S21 or the signal S22, and
7 and the memory 28.
The selection is performed by receiving the display data and receiving the data pulse Vd.
In the write discharge period Tw for outputting i, the count value S
21 during the sustain discharge period Ts.
Select 2. In the writing discharge period Tw, the count value D21 is stored as data for each scan line in the memory 27 with the storage position specified according to the address instruction signal A2, and the count value D22 is stored as data for each sustain block according to the address instruction signal A2. The position is designated and stored in the memory 28. In the sustain discharge period Ts, the number of display data of all scan lines is read out from the memory 27 as a signal D23 and the number of display data of all blocks is read out as a signal D24 from the memory 27 for each sustaining cycle, and supplied to the memory 29. The memory 29 stores data indicating the number of sustain discharges for obtaining a desired luminance in consideration of the relationship between the number of display data in the sustain block unit and the ratio of the luminance variation due to the number of display data in the scan line unit.
And a signal MD instructed by the signal D24 and instructing the number of sustain discharges to the comparator 30. The comparator 30 compares the signal MD and the signal S22, and outputs a sustain stop signal ED when the number of sustain discharges according to the instruction of the signal MD is reached,
It is supplied to the erase driver 32.

Referring to FIG. 9, the conventional P shown in FIG.
Instead of the sustain erase pulse Ve indicating the end of the sustain discharge period Ts in the time chart of the DP drive circuit, Ws11, Ws12, Ws1 indicating the drive waveform of each scan electrode.
m, Ws21, Ws22, Ws2m, Ws31, Ws3
2, Ws3m, Ws3m, Ws41, Ws42, Ws4
m, sustain erase pulses Ve11, Ve12, Ve1m, Ve21, Ve applied at independent timings.
22, Ve2m, Ve31, Ve32, Ve3m, Ve
41, Ve42, and Ve4m are shown. Since the sustain discharge of each scan line is stopped when these sustain erase pulses are applied, the number of sustain discharges is independently controlled for each scan line to perform luminance compensation. Further, since the timing of the sustain erasing pulse is calculated in consideration of the number of display data for each block, even if the number of display data on one scan line is the same, if the number of display data of the belonging block is different, Sustain erase pulses are applied at different timings.

Although the above-described sustain erase pulse in FIG. 9 has been described as an example of a narrow pulse, it is an erase pulse that forms a relatively narrow pulse slightly shifted in phase from the sustain pulse of the opposite electrode. There may be.

Next, a fourth embodiment of the present invention will be described. FIG. 1 is a block diagram showing a configuration of a PDP drive circuit according to a fourth embodiment for realizing the plasma display of the present invention.
0, the PDP 19 and the data driver 11,
12, scan driver 13, sustain pulse drive circuit 14
A to 14D, 15A to 15D, the data distributor 20,
Mixers 16 and 17, luminance compensation circuit 31, timing generator 21, pre-discharge erase pulse drive circuit 22, pre-discharge pulse drive circuit 23, sustain erase pulse drive circuit 24, and luminance instead of the erase driver It includes a sustain pulse stop circuit 33 that receives the sustain stop signal ED of the compensation circuit 31 and the supply of the sustain pulse, and stops the sustain pulse supplied to the PDP 19 in response to the sustain stop signal ED.

The operation will be described with reference to FIG. 10 and FIG. 11 showing a drive time chart of the drive circuit of the present embodiment. The erase data ED output from the luminance compensation circuit 31 is supplied to the sustain pulse stop circuit 33, The pulse stop circuit 33 supplies the sustain pulse to the mixer 16, but stops supplying the sustain pulse thereafter for each scan line when the sustain discharge stop is instructed by the sustain stop signal ED. Looking at the sustain discharge period Ts in FIG. 11, each scan electrode drive waveform Ws1
1, Ws12, Ws1m, Ws21, Ws22, Ws2
m, Ws31, Ws32, Ws3m, Ws3m, Ws4
At 1, Ws42, and Ws4m, the sustain pulse stops at independent timings, and the sustain erase pulse Ve is applied to all scan lines by the sustain erase pulse driving circuit, and the sustain discharge period Ts ends. As described above, the number of sustain discharges of each scanning line is independently controlled to perform luminance compensation.

Next, a fifth embodiment of the present invention will be described. Although a block diagram showing the configuration of the PDP drive circuit can be realized by the same configuration as that of FIG. 10 shown in the fourth embodiment, the description is omitted. However, referring to FIG. 12 showing a drive time chart of the drive circuit of the present embodiment, In the sustain discharge period Ts, each scan electrode drive waveform Ws11, Ws12, Ws1m, Ws
21, Ws22, Ws2m, Ws31, Ws32, Ws
At 3m, Ws41, Ws42, and Ws4m, the state in which the sustain pulse voltage is applied is started at independent timing, and the state is maintained until immediately before the final sustain pulse of the sustain electrode drive waveform Wu. The sustain discharge period Ts ends when the sustain erase pulse Ve common to all scan lines is applied. During the state where the sustain pulse voltage is still applied to the scan electrode, the sustain discharge does not occur because the potential reversal between the scan electrode and the sustain electrode does not occur even if the sustain pulse is repeatedly applied in the sustain electrode drive waveform Wu. Stop. As described above, the number of sustain discharges of each scanning line is independently controlled to perform luminance compensation. In this method, the same effect can be obtained by repeatedly applying a sustain pulse having the same phase as the sustain pulse Vsu of the sustain electrode drive waveform Wu to the scan electrodes during the sustain discharge suspension period.

Although several embodiments have been described above, the present invention is not limited to a three-electrode structure as long as the PDP has a parallel sustain discharge electrode structure. A color PDP having a phosphor layer is also effective.

Further, even when one field is divided into a plurality of sub-fields and multi-gradation display is performed by weighting the number of sustain discharges in each sub-field, the data indicating the maintenance stop timing is determined by the number of display data. If a memory to be stored is prepared for each subfield, it goes without saying that all the luminance compensation methods described above can be applied. Also, in this case, the simplification may be performed by applying luminance compensation only to the upper subfield that has a large effect.

[0056]

As described above, the plasma display of the present invention can display the entire display screen with uniform luminance by reducing the luminance difference between each scan line and each sustain block.
There is an effect that display with good halftone and chromaticity can be realized by preventing crosstalk.

[Brief description of the drawings]

FIG. 1 is a block diagram showing a first embodiment of a luminance compensation circuit in a plasma display of the present invention.

FIG. 2 is a block diagram of a PDP drive circuit including a luminance compensation circuit according to the present embodiment.

FIG. 3 is a time chart illustrating an example of an operation in the present embodiment.

FIG. 4 is a block diagram showing a second embodiment of the luminance compensation circuit in the plasma display of the present invention.

FIG. 5 is a block diagram of a PDP drive circuit including the luminance compensation circuit according to the present embodiment.

FIG. 6 is a time chart illustrating an example of an operation in the present embodiment.

FIG. 7 is a block diagram showing a third embodiment of the luminance compensation circuit in the plasma display of the present invention.

FIG. 8 is a block diagram of a PDP drive circuit including the luminance compensation circuit according to the present embodiment.

FIG. 9 is a time chart illustrating an example of an operation in the present embodiment.

FIG. 10 is a block diagram of a PDP circuit according to a fourth embodiment including a luminance compensation circuit in the plasma display of the present invention.

FIG. 11 is a time chart illustrating an example of an operation in the present embodiment.

FIG. 12 is a time chart showing the operation of the fifth embodiment in the present embodiment.

FIG. 13 is a cross-sectional view showing a configuration of one display cell of the AC memory type PDP.

FIG. 14 is a plan view showing an electrode arrangement of an AC memory type PDP.

FIG. 15 is a block diagram illustrating an example of a drive circuit of an AC memory type PDP.

FIG. 16 is a time chart showing an example of a drive voltage waveform of an AC memory type PDP.

FIG. 17 is a plan view showing an electrode arrangement of an AC memory type PDP.

[Explanation of symbols]

1, 2, 3, 25, 26 Counters 7, 7A to 7D, 30 Comparator 4, 6, 10, 27, 28, 29 Memory 5 Selector 11, 12 Data driver 13 Scan driver 14A to 14D, 15A to 15D Sustain pulse Generation circuit 16, 17 Mixer 8, 18, 31 Brightness compensation circuit 9, 19 PDP 20 Data distributor 21 Timing generator 22 Priming erase pulse drive circuit 23 Priming pulse drive circuit 24 Sustain erase pulse drive circuit 32 Erase driver 33 Sustain pulse Stop circuit 34 Display cell 35 Partition wall 36, 43 Dielectric 37 Scan electrode 38 Discharge gas space 39, 45 Insulating substrate 40 Sustain electrode 41 Protective film 42 Phosphor 44 Data electrode Sc1, Sc2, ..., Scj, Sc11, Sc12,
, Sc4m scanning electrodes Su1, Su2, ..., Suj, Su11, Su12,
..., Su4m sustain electrode D1, D2, ..., Dk Data electrode

Claims (10)

(57) [Claims] A scan electrode group comprising a plurality of scan electrodes corresponding to a scan line of a display cell formed on the same plane; a sustain electrode group comprising a plurality of sustain electrodes for sustaining discharge of the display cell; In a method for driving a plasma display, comprising at least a data electrode group consisting of a plurality of data electrodes for data writing which is orthogonal to an electrode group and a sustain electrode group and driven according to display data, a write discharge period for selecting a display cell and the selection The sustained discharge period for sustaining light emission of the displayed display cell is separately driven,
Counting at least one set of the display data quantity for each correction unit display line formed of the scan electrodes and the sustain electrodes and the number of display data of all the scanning line, calculated by the luminance variation coefficient predetermined in correspondence with the count value A plasma display, wherein the number of sustain discharges for obtaining a desired luminance is obtained for each correction unit display row, and the sustain discharge is stopped after the number of sustain discharges ends for each correction unit display row. Brightness compensation method. 2. A scan electrode group consisting of a plurality of scan electrodes corresponding to scan lines of a display cell formed on the same plane, a sustain electrode group consisting of a plurality of sustain electrodes for sustaining discharge of said display cell, and said scanning. In a method for driving a plasma display, comprising at least a data electrode group consisting of a plurality of data electrodes for data writing which is orthogonal to an electrode group and a sustain electrode group and driven according to display data, a write discharge period for selecting a display cell and the selection The sustained discharge period for sustaining light emission of the displayed display cell is separately driven,
And, a scanning electrode group and the sustain electrodes is divided by a plurality of sustain pulse drive circuit sustain discharge driving, the number of display data of the display data number and the total scanning line of the display cell to be driven by each of the sustain pulse drive circuit And count
The number of sustain discharges for obtaining a desired luminance for each sustain pulse drive circuit is calculated by a predetermined luminance variation coefficient corresponding to the count value , and the predetermined number of sustain discharges for each sustain pulse drive circuit is calculated. And stopping the sustain discharge after the termination of the process. 3. A scan electrode group consisting of a plurality of scan electrodes corresponding to scan lines of a display cell formed on the same plane, a sustain electrode group consisting of a plurality of sustain electrodes for sustaining discharge of said display cell, and said scanning. In a method for driving a plasma display, comprising at least a data electrode group consisting of a plurality of data electrodes for data writing which is orthogonal to an electrode group and a sustain electrode group and driven according to display data, a write discharge period for selecting a display cell and the selection The sustained discharge period for sustaining light emission of the displayed display cell is separately driven,
And, a scanning electrode group and the sustain electrodes is divided by a plurality of sustain pulse drive circuit sustain discharge driving, the number of display data of the display data number and the total scanning line of the display cell to be driven by each of the sustain pulse drive circuit counting the number of display data correction unit display each row comprising at least one pair or more preparative run scan electrodes and sustain electrodes, the maintenance of the correction unit display each row is calculated by the luminance variation coefficient predetermined from the count value A brightness compensation method for a plasma display, comprising: determining a number of discharges; and stopping the sustain discharge after a predetermined number of sustain discharges ends for each correction unit display row. 4. The brightness compensation method for a plasma display according to claim 1, wherein the sustain discharge is stopped by applying an erase pulse to said scan electrode or said sustain electrode. 5. A sustain discharge is stopped by applying an erasing pulse to the scan electrode or the sustain electrode, and all sustain discharges in a display region of the sustain pulse drive circuit are stopped for each sustain pulse drive circuit. 4. The method of claim 2, wherein the sustain pulse of the sustain pulse driving circuit is stopped. 6. A sustain discharge is stopped by one of a sustain pulse to the scan electrode and a sustain pulse to the sustain electrode, or
4. The method according to claim 1, wherein the method is performed by stopping both. 7. A sustain discharge is stopped by applying a sustain pulse having the same phase as the sustain pulse to the sustain electrode to the scan electrode, or applying a sustain pulse having the same phase as the sustain pulse to the scan electrode to the sustain electrode. 4. The method according to claim 1, wherein the method is performed by applying a voltage. 8. A scan electrode group consisting of a plurality of scan electrodes corresponding to scan lines of a display cell formed on the same plane, a sustain electrode group consisting of a plurality of sustain electrodes for sustaining discharge of said display cell, and said scan electrode. A plasma display comprising at least a data electrode group consisting of a plurality of data electrodes for data writing, which is orthogonal to the group and the sustain electrode group and is driven in accordance with display data, wherein the correction comprises at least one set of a scan electrode and a sustain electrode. the number of display data of the unit display each row and the display data of the total scanning line
Arithmetic circuit for obtaining a counting circuit for counting the number, the number of sustain discharges for obtaining a desired luminance count to be calculated by the luminance variation coefficient predetermined in correspondence with each of the correction unit display line of the counting circuit An erase pulse drive circuit or a sustain pulse stop circuit having a function of stopping the sustain discharge after the number of record keeping discharges is completed for each of the correction unit display rows based on the number of sustain discharges obtained by the arithmetic circuit. A plasma display device characterized in that: 9. A scan electrode group consisting of a plurality of scan electrodes corresponding to scan lines of a display cell formed on the same plane, a sustain electrode group consisting of a plurality of sustain electrodes for sustaining discharge of said display cell, and said scan electrode. A plasma display comprising at least a data electrode group composed of a plurality of data electrodes for data writing, which is orthogonal to the group and the sustain electrode group and is driven in accordance with display data, wherein the scan electrode group and the sustain electrode group are divided into sustain discharges. A plurality of sustain pulse driving circuits to be driven, and the number of display data of display cells driven by each sustain pulse driving circuit and the number of display data of all scan lines are counted.
An arithmetic circuit for calculating the number of sustain discharges for obtaining a desired luminance for each sustain pulse driving circuit by calculating with a predetermined luminance variation coefficient corresponding to the count value of the counting circuit; An erase pulse drive circuit or a sustain pulse stop circuit having a function of stopping the sustain discharge after the predetermined number of sustain discharges is completed for each sustain pulse drive circuit based on the number of sustain discharges obtained by the circuit. Plasma display device. 10. A scan electrode group consisting of a plurality of scan electrodes corresponding to scan lines of a display cell formed on the same plane, a sustain electrode group consisting of a plurality of sustain electrodes for sustaining discharge of said display cell, and said scan electrode. A plasma display comprising at least a data electrode group consisting of a plurality of data electrodes for data writing, which is orthogonal to the group and the sustain electrode group and driven in accordance with display data, wherein the scan electrode group and the sustain electrode group are divided into sustain discharges. be counted and a plurality of sustain pulse drive circuit for driving, and a number of display data of the display cell to be driven by each of the sustain pulse drive circuit and a display number data of all the scan line
A first counting circuit, a second counting circuit for counting the number of display data for each correction unit display row comprising at least one set of a scanning electrode and a sustaining electrode, and a total of the first and second counting circuits. An arithmetic circuit for calculating the number of sustain discharges for each correction unit row by calculating based on a predetermined luminance variation coefficient from a numerical value ; and a predetermined sustain discharge for each correction unit row based on the number of sustain discharges obtained by the arithmetic circuit. A plasma display device comprising: an erase pulse driving circuit or a sustain pulse stop circuit having a function of stopping a sustain discharge after the number of times has been completed.