JP2010113246A - Plasma display device and method of driving the same - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a plasma display device for efficiently reducing the reactive power. <P>SOLUTION: In this plasma display device, one field includes a plurality of subfields, and video is gradation-represented by selecting lighting or no-lighting of each subfield. In the plasma display device, a display ratio for each subfield related to an input video signal is detected. When the detected display ratio is determined to be a set threshold or lower, an output of a driving waveform of a plasma display panel in the subfield is stopped, and no-lighting is performed not only in a subfield having no lighting cell but also in a subfield where the number of lighting cells is a predetermined number or less, thereby efficiently reducing the reactive power. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a plasma display device and a driving method thereof.

  In the plasma display device, in order to improve contrast and reduce power consumption, a method of stopping a driving pulse when there is no image bit information in one field or one subfield has been proposed (for example, , See Patent Document 1). In Patent Document 1, it is determined whether or not there is an image signal having a predetermined gradation or more in one field for all effective image areas of the plasma display panel. In this field, a method for stopping the driving pulse in the field to improve contrast and a method for reducing power consumption has been proposed.

  Further, a method has been proposed in which a subfield that causes light emission to the display cell at the end of one field is detected, and a driving pulse is stopped in subsequent subfields to reduce reactive power (for example, Patent Documents). 2).

JP-A-10-171403 JP 2006-84625 A

  However, in the conventional method described above, the frequency of fields and subfields in which there is no image bit information in one field or one subfield at the time of normal image display is very low, that is, the drive pulse is stopped. The frequency was low and the effect of reducing power consumption was small. For example, in the conventional method, the drive pulse is not stopped even when the display rate of the subfield is 1% and there are almost no cells to be lit, so the power consumed by the remaining cells that are not lit contributes to light emission. Not reactive power.

  The objective of this invention is providing the plasma display apparatus which can reduce power consumption, and its drive method.

  According to an aspect of the present invention, there is provided a driving method of a plasma display apparatus in which an image of one frame is displayed by a plurality of subfields, and at least one of the plurality of subfields is applied with a sustain pulse to light a cell. And driving the plasma display apparatus to stop application of at least a part of the sustain pulse in the subfield when a display rate, which is a ratio of cells to be lit in the subfield, is equal to or less than a threshold value. A method is provided.

  Power consumption can be reduced by stopping the output of the drive waveform even in a subfield whose display rate is equal to or less than the threshold.

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

(First embodiment)
A first embodiment of the present invention will be described.
First, the method for stopping the output of the drive waveform of the subfield whose display rate is equal to or less than the threshold value, which is the basic concept of the present invention, will be described with reference to FIGS. Next, a specific example relating to the stop of the drive waveform will be described with reference to FIGS. Furthermore, setting of the threshold value for each subfield will be described with reference to FIGS.

  FIG. 1 is a block diagram illustrating a configuration example of the plasma display device according to the first embodiment. The plasma display device according to the first embodiment includes an address electrode drive circuit 111, a sustain electrode drive circuit 112, a scan electrode drive circuit 113, a plasma display panel 114, and a control circuit 115.

  In the plasma display panel 114, the Y electrode Yi and the X electrode Xi form a row extending in parallel in the horizontal direction, and the address electrode Aj forms a column extending in the vertical direction. The Y electrodes Yi and the X electrodes Xi are alternately arranged in the vertical direction.

  The Y electrode Yi and the address electrode Aj form a two-dimensional matrix with i rows and j columns. The display cell Cij is formed by the intersection of the Y electrode Yi and the address electrode Aj and the X electrode Xi adjacent thereto corresponding thereto. This display cell Cij corresponds to, for example, red, green, and blue sub-pixels, and one pixel is constituted by these three-color sub-pixels. The plasma display panel 114 can display a two-dimensional image by lighting a plurality of pixels arranged two-dimensionally.

  The address electrode drive circuit 111 supplies a predetermined voltage to the address electrodes A1, A2,... Formed on the plasma display panel 114. Hereinafter, each of the address electrodes A1, A2,... Or their generic name is referred to as an address electrode Aj, where j means a subscript.

  The sustain electrode drive circuit 112 supplies a predetermined voltage to the X electrodes (sustain electrodes) X1, X2,... Formed on the plasma display panel 114. Hereinafter, each of the X electrodes X1, X2,... Or their generic name is referred to as an X electrode Xi, and i means a subscript.

  The scan electrode driving circuit 113 supplies a predetermined voltage to the Y electrodes (scan electrodes) Y1, Y2,... Formed on the plasma display panel 114. Hereinafter, each of the Y electrodes Y1, Y2,... Or their generic name is referred to as a Y electrode Yi, and i means a subscript.

  The sustain electrode drive circuit 112 and the scan electrode drive circuit 113 may be configured as a common circuit to supply a voltage to the X electrode Xi and the Y electrode Yi.

  The address electrode drive circuit 111, the sustain electrode drive circuit 112, and the scan electrode drive circuit 113 are controlled by a control circuit 115. Details of the control circuit 115 will be described later.

  FIG. 2 is a diagram illustrating an example of drive waveforms applied to each electrode of the plasma display panel 114 from the address electrode drive circuit 111, the sustain electrode drive circuit 112, and the scan electrode drive circuit 113 of FIG. The video is composed of a plurality of time-series fields (frames) F such as fields Fk-1, Fk, and Fk + 1 shown in FIG. In the image display, since gradation reproduction is performed by binary lighting control for each pixel, each field (frame) F is divided into, for example, eight subfields SF1, SF2, SF3, SF4, SF5, SF6, SF7, Divide into SF8. The subfields SF1 to SF8 are weighted so that the relative luminance ratio is, for example, approximately 1: 2: 4: 8: 12: 16: 22: 30, and the number of sustain discharges in each of the subfields SF1 to SF8 is set. . That is, the sustain pulse is applied more in the subfield with higher luminance weight.

  A subfield period TSF assigned to each of the subfields SF1 to SF8 is configured by a reset period TR, an address period TA, and a sustain (sustain discharge) period TS. In the reset period TR, the display cell Cij is initialized. In the reset period TR, positive obtuse waves (waveform having a positive slope) Pr1 are simultaneously applied to the Y electrode Yi to form wall charges, and then negative obtuse waves (waveform having a negative slope). ) Pr2 is applied all at once to adjust the wall charge amount of the display cell Cij.

  In the address period TA, light emission or non-light emission of each display cell Cij according to video data can be selected by discharge between the address electrode Aj and the Y electrode Yi and accompanying discharge between the X electrode Xi and the Y electrode Yi. it can. Specifically, the scan electrode Py is sequentially applied to the Y electrodes Y1, Y2, Y3,... And the address pulse Pa is applied to the address electrode Aj corresponding to the scan pulse Py. And discharge occurs between the Y electrodes Yi. By this discharge, wall charges are formed on the X electrode Xi and the Y electrode Yi, and light emission or non-light emission of a desired display cell Cij can be selected.

  In the sustain period TS, a sustain discharge (sustain discharge) is performed between the X electrode Xi and the Y electrode Yi of the display cell Cij selected according to the video data to emit light. The sustain period TS includes a pre-processing period TSP, a sustain loop period SLP, and a post-processing period TSS. In the sustain loop period SLP, a sustain pulse (sustain discharge pulse) Ps is alternately applied to the X electrode Xi and the Y electrode Yi.

  In the pre-processing period TSP and the post-processing period TSS, a sustain pulse for performing charge adjustment or the like different from the sustain pulse Ps in the sustain loop period SLP is applied to the X electrode Xi and / or the Y electrode Yi. In the example shown in FIG. 2, in the preprocessing period TSP, a sustain pulse Psy1 (preprocess pulse) having a voltage higher than the normal sustain pulse Ps and somewhat longer in time is applied to the Y electrode Yi, and is higher than the normal sustain pulse Ps. A sustain pulse Psx (pretreatment pulse) having a slightly longer time is applied to the X electrode Xi. In the example shown in FIG. 2, in the post-processing period TSS, a sustain pulse Psy2 (post-processing pulse) whose time is somewhat longer than the normal sustain pulse Ps is applied to the Y electrode Yi.

  In the sustain period TS, every time a sustain pulse Ps (Psx, Psy1, Psy2) is applied to the X electrode Xi and the Y electrode Yi, a discharge occurs in the display cell in which wall charges are formed in the address period TA, and the display cell emits light. To do.

  The drive waveform shown in FIG. 2 is an example, and the present invention is not limited to this, and various changes can be made. For example, a drive waveform having no reset period or a drive waveform having no sustain period can be applied. Further, the number of subfields constituting each field is not limited to eight, and the number of subfields is arbitrary. In addition, the weighting (relative ratio of luminance) for each subfield constituting the field is not limited to the above-described example, and is arbitrary, but in each embodiment of the present invention, it is higher than the lower subfield. It is assumed that the weight of the subfield of is large. For example, if one field is composed of eight subfields SF1 to SF8, the lowest subfield is SF1 and the highest subfield is SF8, SF1 <SF2 <SF3 <SF4 <SF5 <SF6 <SF7 <SF8. It is assumed that each subfield is weighted so as to satisfy the relationship. Further, the number of sustain pulses to be applied satisfies the relationship of SF1 <SF2 <SF3 <SF4 <SF5 <SF6 <SF7 <SF8, and the higher number of sustain pulses is applied to the upper subfield.

  In this way, the plasma display panel 114 of FIG. 1 selects an image composed of a plurality of subfields in which one field (one frame) is weighted by selecting lighting or non-lighting of the plurality of subfields. Is expressed by gradation.

  Here, the operation of the control circuit 115 that controls the voltage supplied to the plasma display panel of FIG. 1 will be described. The control circuit 115 includes an inverse gamma conversion unit 10, a nonlinear gain conversion unit 20, an error diffusion processing unit 30, a subfield data storage unit 40, a subfield display rate detection unit 50, a sustain pulse number setting unit 60, and a subfield display rate. The determination unit 70 includes a drive pulse stop unit 80, a control signal generation unit 90, and a nonlinear parameter determination unit 100.

  The inverse gamma converter 10 receives a digital video signal (video data) S1 and performs inverse gamma conversion.

  The non-linear gain conversion unit 20 determines the subfield to be lit in accordance with the gradation of the video signal, and the video signal subjected to the reverse gamma conversion by the reverse gamma conversion unit 10 according to the lighting pattern of the subfield. To perform non-linear conversion. For example, when the luminance weight of the input video signal is 8 and the luminance having the weights 7 and 11 can be displayed in the lighting pattern of the subfield, but cannot be displayed during that time, the luminance weight is 7 to 11 It is converted to 7 which is close to 8 which is the luminance weight of the video signal. That is, the video signal data is converted into data that can be subfield converted. An error between the gradation level of the input video signal and the converted gradation level is processed by an error diffusion processing unit 30 described below.

  The error diffusion processing unit 30 inputs the video signal nonlinearly converted by the nonlinear gain conversion unit 20, and if the converted video signal has an error, the error diffusion processing unit 30 diffuses the error spatially or temporally, A video signal for gradation expression is output.

  When the video signal output from the error diffusion processing unit 30 is input, the subfield data storage unit 40 converts the video signal into data representing lighting / non-lighting for each subfield, and stores the data. 111 and the display rate detection unit 50 for each subfield. For example, when a video signal having a luminance weight of 7 is input, the subfields SF1 to SF3 are turned on, and the subfields SF4 to SF8 are turned off. The address electrode driving circuit 111 generates a voltage of the address electrode Aj, that is, an address voltage, for selecting a subfield to be lit for each pixel in accordance with the video data of the subfield sent from the subfield data storage unit 40.

  The display rate detection unit 50 for each subfield calculates the display rate for each subfield based on the video data of the subfield generated by the subfield data storage unit 40. Here, the display rate of the subfield refers to the ratio of the number of cells to be lit to the number of cells constituting one screen in a certain subfield. When the number of cells to be lit increases in a certain subfield, the display rate increases in proportion thereto. Further, the ratio of the area of the cells that are lit in a certain subfield to the area of one screen on which the cells are arranged can be used as the display rate. As described above, the display rate detection unit 50 for each subfield detects the display rate in the plasma display panel 114 for each subfield.

  The sustain pulse number setting unit 60 receives the display rate detected by the subfield display rate detection unit 50, and calculates the total number of sustain pulses for one field in order to perform power control. The power control is performed based on a display load factor of one frame which is a ratio of the average gradation level of the input video to the maximum gradation level. Further, the display load factor may be calculated by weighting and averaging the display rate of the subfield. For example, when the display load factor of one field is large, calculation is performed so as to reduce the total number of sustain pulses in one field, and power control is performed. Further, the sustain pulse number setting unit 60 divides the total number of sustain pulses so as to be a weight ratio of each subfield according to the subfield arrangement selected by the nonlinear parameter determination unit 100.

  The display rate determination unit 70 for each subfield receives the display rate for each subfield obtained by the display rate detection unit 50 for each subfield, and whether or not the display rate for each subfield is equal to or less than a set threshold value. Determine whether. Note that the threshold of the display rate is a value larger than 0, and the setting thereof will be described later.

  The drive pulse stop unit 80 outputs a command for stopping the output of the drive waveform (drive pulse) of the plasma display panel 114 to the control signal generation unit 90 according to the determination result in the display rate determination unit 70 for each subfield. To do. Specifically, the drive pulse stop unit 80 generates a control signal so as to stop output of the drive waveform in the subfield when the display rate determination unit 70 determines that the display rate is equal to or less than the threshold value. An instruction is given to the unit 90.

  The control signal generation unit 90 generates a control signal for display. The address electrode drive circuit 111, the sustain electrode drive circuit 112, and the scan electrode drive circuit 113 generate a voltage to be applied to the address electrode Ai, the X electrode Xi, and the Y electrode Yi according to the control signal. The control signal generation unit 90 generates a control signal (sustain pulse control signal), for example, according to the output of the sustain pulse number setting unit 60. The control signal is a signal that controls the timing at which each drive circuit operates. For example, in FIG. 17, the control signal generated by the control signal generation unit 90 controls the timing for turning on and off each switch, and generates the drive waveform for the Y electrode Yi in FIG.

  When the control signal generation unit 90 receives a command to stop the output of the drive waveform from the drive pulse stop unit 80, the control signal generation unit 90 sends the control signal to each drive circuit, thereby driving the drive waveform for the plasma display 114 in the subfield. Control to stop the output of. Control for stopping the output of the drive waveform is performed by fixing the potential of each electrode to the ground level or an arbitrary potential, or by interrupting the supply of voltage to each electrode. When the output of the drive waveform is stopped, for example, the potentials of the X electrode Xi and the Y electrode Yi are fixed to the ground level or an arbitrary potential in the sustain period TS of FIG. Further, in the address period TA in FIG. 2, the supply of voltage to the address electrode Ai and the Y electrode Yi is cut off, and a high impedance state is entered. In this case, the operation of the control signal generation unit 90 will be described with reference to FIG. 17 showing the circuit configuration of the Y electrode drive circuit. For example, the control signal generation unit 90 turns on the switches SW2, SW6, and SW10 in FIG. A control signal is sent to set the Y electrode Yi to a ground level potential, or a control signal to turn off the switches SW1, SW2, and SW6 is sent to cut off the connection to the Y electrode Yi to bring it into a high impedance state. The output of the drive waveform of the electrode Yi is stopped.

  FIG. 16 is a flowchart showing the processing of this embodiment. The processing in FIG. 16 is performed by each block of the control circuit 115 in FIG. In this embodiment, when display signal (video signal) data is input in step S101, nonlinear gain processing is performed in order to convert the video signal into subfield data in step S103. In step S104, error diffusion processing for diffusing errors caused by the nonlinear gain processing of the video signal is performed. That is, in step S103 and step S104, processing (step S102) is performed in which the video signal is converted into subfield data corresponding to the subfield lighting pattern. In step S105, processing for detecting the display rate for each subfield is performed, and in step S106, processing for determining whether the display rate is equal to or greater than the threshold value is performed for each subfield. For the subfield for which the display rate is determined to be equal to or less than the threshold value, processing for stopping output of the drive waveform is performed in step S108. If there is a subfield for which the display rate is determined to be greater than or equal to the threshold value, a process of switching the lighting pattern of the subfield in step S107 in order to prevent deterioration in image quality due to lack of video data of the subfield for which output is to be stopped. May be performed.

  FIG. 3 is a diagram showing the relationship between the display rate of the subfield in the present embodiment and the output state of the drive pulse controlled by the control circuit 115 shown in FIG. R indicates a reset period, A indicates an address period, S indicates a sustain period, “◯” in the output state indicates that a drive waveform is output, and “×” indicates that a drive waveform is not output. ing.

  In FIG. 3, when the threshold value of the display rate in each subfield is set to 5%, the subfield SF2 having a display rate of 4% and the subfield SF8 having a display rate of 0% are not lit. Accordingly, it is possible to reduce the useless power consumption (reactive power) that does not contribute to the display of the video by stopping the output of the drive waveform in the address period and the sustain period of the plasma display 114 in the subfields SF2 and SF8.

  As described above, in this embodiment, when the display rate of the subfield is equal to or lower than the threshold value, the driving waveform is stopped to reduce the reactive power that does not contribute to the video display when most of the cells are not lit. , Power consumption can be reduced. On the other hand, when the drive waveform is not stopped, even if most of the cells are not lit, for example, the scan pulse and the sustain pulse are applied to all lines every time, and power is consumed. Therefore, this embodiment is effective for reducing power consumption.

  Next, a driving waveform stop mode will be described. FIG. 4 shows an example of a case where the display rate is determined to be equal to or less than the threshold value and the output of the drive waveform is stopped.

  The drive waveform shown in FIG. 4A is a drive waveform during normal operation. In FIG. 4, TRA is an all-cell reset period in which all display cells are initialized, and TRO is an on-cell reset period in which only display cells (on cells) that are lit in the previous subfield are initialized. . TA is an address period, TS is a sustain period, and the sustain period TS has a pre-processing period TSP, a sustain loop period SLP, and a post-processing period TSS.

  FIG. 4B illustrates a case where the drive waveform output in the on-cell reset period is stopped without stopping the drive waveform output in the all-cell reset period in the period in the subfield that is the target of the drive waveform output stop. Show. This is because when the output of the drive waveform related to the all-cell reset is stopped, the black level in the plasma display panel 114 fluctuates. Therefore, the output of the drive waveform in the all-cell reset period is not stopped to prevent this.

  Even if the subfield for which the output of the drive waveform is to be stopped is a subfield that is set to perform all cell reset, if all cell reset can be executed in another subfield in the field, the drive waveform In the subfield that is the output stop target, the output of the drive waveform may be stopped in all periods including the all-cell reset period, and the all-cell reset may be executed in the other subfield. For example, if the subfield SF1 is a subfield that is set to reset all cells, and the drive waveform output stop target is the subfields SF1 and SF2, the drive waveform output in the subfields SF1 and SF2 is completely output. It is also possible to stop and stop all cells in the subfield SF3 or the like.

  If the video is completely black (all cells are not lit over one field), the drive waveform output related to the all cell reset may be stopped.

  In FIG. 4C, in the subfield that is the target for stopping the output of the drive waveform, the output of the drive waveform is stopped in the sustain period TS, and the drive is performed in the other periods (reset periods TRA, TRO, and address period TA). This shows a case where waveform output is not stopped. In the plasma display device, a large amount of power is consumed in the sustain period TS in which the sustain pulse is applied. Therefore, as shown in FIG. 4C, high reactive power can be reduced even when the output of the drive waveform is stopped only in the sustain period TS. An effect can be obtained.

  FIG. 4D shows a case where the output of the drive waveform is stopped only in the sustain loop period SLP in the sustain period TS in the subfield that is the target of stopping the output of the drive waveform. The pre-processing period TSP and the post-processing period TSS in the sustain period TS are also periods during which charge adjustment is performed. In this period TSP and TSS, if the output of the drive waveform is stopped, the next subfield may be affected. is there. Therefore, also from the viewpoint of the drive margin, it is preferable to output the drive waveform in the preprocessing period TSP and the postprocessing period TSS as shown in FIG. 4D, and furthermore, it does not affect the next subfield. In addition, it is preferable to output a drive waveform at least in the post-processing period TSS.

  When stopping the output of the drive waveform in the plasma display device, the output of the drive waveform is stopped by any one of the stop methods shown in FIGS. Note that the example shown in FIG. 4 is an example, and the present invention is not limited to this. In FIG. 4, only the drive waveform applied to the Y electrode Yi is shown. However, the reference potential (for example, the ground level) is also output during the period in which the drive waveform output is stopped for the X electrode Xi and the address electrode Aj. ).

  Here, control for stopping the drive pulse will be described with reference to FIG. FIG. 17 shows an example of a circuit diagram of the Y drive circuit 113 shown in FIG. Here, Vs is a power supply for applying a sustain pulse voltage. Vsc and -Vy are power supplies for applying a scan pulse. Vw is a power source for applying a reset pulse. The voltage applied to the Y electrode is controlled by controlling ON / OFF of the switches SW1 to SW10. Here, when a sustain pulse (voltage of Vs) is applied to the Y electrode, the switches SW2, SW6, and SW9 are turned on and the other switches are turned off. When the Y electrode is connected to the ground, the switches SW2, SW6, and SW10 are turned on and the other switches are turned off. When the Y electrode is connected to a potential other than the ground, for example, the potential of the Y electrode can be set to Vsc by turning on the switches SW1, SW6, and SW10 and turning off the other switches. Further, when the Y electrode is cut off to be in a high impedance state, the switches SW1, SW2, and SW6 are turned off. The same control is performed for the address drive circuit 111 and the X drive circuit 112, and output of the drive waveform is stopped.

  Next, the setting of the display rate threshold value in each subfield will be described. FIG. 5 and FIG. 6 are diagrams showing a display rate as a reference for stopping the drive waveform for each subfield. FIG. 7 is a lighting table showing which subfield is to be turned on with respect to the luminance of the input video signal. In FIG. 7, the luminance weight of the subfield SF1 is 1, the luminance weight of the subfield SF2 is 2, and the luminance weight of the subfield SF8 is 30. That is, the luminance of the subfield SF8 is the largest and the number of applied sustain pulses is the largest. For example, when the luminance weight of 43 that is the 21st luminance is to be displayed using the table shown in FIG. 7, the subfields SF1 to SF6 are turned on, and the subfields 7 and 8 are not turned on. Here, the display rate threshold setting example and the lighting table shown below are merely examples, and the present invention is not limited to this, and various settings are possible.

  As for the threshold of the display rate, the same threshold may be set for each subfield as shown in FIG. 5, or the threshold may be varied depending on the subfield as shown in FIG. good. In FIGS. 5 and 6, as described above, the luminance weighting for each subfield is assumed to satisfy the relationship of SF1 <SF2 <SF3 <SF4 <SF5 <SF6 <SF7 <SF8. . Similarly, the number of applied sustain pulses satisfies the relationship SF1 <SF2 <SF3 <SF4 <SF5 <SF6 <SF7 <SF8. In the following description, subfield SF1 is the lowest subfield and subfield SF8 is the highest subfield according to the weight (number of applied sustain pulses).

  FIG. 5 shows a case where the same threshold value (1.0% in the illustrated example) is set for each subfield SF (1-8). In this case, for each subfield, when the display rate is 0.5%, the drive pulse is not applied by the stop operation, but when it is 1.5%, the drive pulse is applied. In general, the frequency with which the display rate of the subfield is 0% is extremely low. On the other hand, when the threshold of the display rate of the subfield is set to 1% and the output of the drive waveform is stopped (when the threshold is regarded as the number of cells to be lit, the number of cells to be lit is about 20000 or less with respect to the total number of cells of about 20000 In this case, since the output of the drive waveform is stopped when the number of lit cells in each subfield is 0 to about 20000, the output of the drive waveform is stopped only when the number of lit cells is 0, compared to the conventional case. However, the frequency of stopping the drive waveform increases.

  From the above, if the threshold is set as 1%, for example, the frequency of stopping the drive waveform is increased as compared with the conventional method. Note that the threshold is preferably 5% or less in consideration of the influence on the image quality. However, when the power consumption is given priority over the influence on the image quality, the threshold value can be set to about 10% for a specific subfield.

  FIG. 6A is an example in which the threshold value of the display rate is increased in the upper subfield. In FIG. 6A, the display rate threshold is set to 0.5% for the lower subfields (subfields SF1 to SF4 whose weights are less than a predetermined value), and the upper subfields (subweights whose weights are equal to or greater than the predetermined value). For the fields SF5 to SF8), the threshold of the display rate is set to 5.0%. That is, the display rate threshold value of subfields SF5 to SF8 is set to a value larger than the display rate threshold value of subfields SF1 to SF4 having a smaller number of sustain pulses than subfields SF5 to SF8. Here, the subfield SF4 is used as the lower subfield, but the subfield SF1 may be used as the lower subfield and the subfield SF7 may be used as the lower subfield.

  Here, in the plasma display device, it is effective to reduce reactive power to stop more sustain pulses. Therefore, by increasing the threshold value of the display rate in the upper subfield having a larger number of sustain pulses as described above, the sustain pulses that do not contribute to light emission can be stopped more frequently, and the reactive power reduction effect can be improved. . Further, by reducing the display rate threshold value of the lower subfield with a small number of sustain pulses, the frequency of loss of video data with a small luminance weight can be reduced, and gradation expression can be maintained. For example, in a relatively dark image or the like, there are no or few cells to be lit in the upper subfield, and therefore only the lower subfield capable of expressing a low gradation may be lit, and application of this method is preferable.

  FIG. 6B shows an example in which the threshold value of the display rate is reduced in the upper subfield. In FIG. 6B, the display rate threshold is set to 1.0% for the lower subfields (subfields SF1 to SF4), and the number of sustain pulses is larger than that of the upper subfield (subfields SF1 to SF4). For the fields SF5 to SF8), the threshold value of the display rate is set to 0.5%. That is, the display rate threshold value of subfields SF5 to SF8 is set to a value smaller than the display rate threshold value of subfields SF1 to SF4 having a smaller number of sustain pulses than subfields SF5 to SF8. Thus, by reducing the threshold value of the display rate for the upper subfield, the reactive power can be reduced while suppressing image quality deterioration due to loss of video data of the upper subfield having a higher luminance. For example, in a relatively bright image, the image can be generally expressed in the upper subfield, and the contribution to the image expression in the lower subfield may be low.

  FIG. 6C shows an example in which a threshold value of the display rate is individually set in each subfield. By individually setting the display rate threshold for each subfield in this way, the reactive power can be further reduced and the degradation of image quality can be suppressed in consideration of the balance between the reduction of reactive power and the effect on image quality. Can do. In other words, the threshold value of the subfield that contributes to the video expression is set lower than the other subfields, and the threshold value of the subfield that contributes to the video expression is set higher than the other subfields. Is effective. Therefore, if the ratio of the subfields SF4 to SF6 that are not limited to the example of FIG. 6C contributes to the video is high, the threshold value is set to 0.5%, and the threshold values of the other subfields are set to 1.0%. If the ratio of the subfields SF4 to SF6 contributing to the video is low, the threshold value may be set to 1.0%, and the threshold values of the other subfields may be set to 0.5%.

  FIG. 6D is an example in which a threshold value of a display rate is set in a specific subfield. In FIG. 6D, the display rate threshold is set to 1.0% only for the uppermost subfield SF8. Since the sustain pulse is applied most frequently in the uppermost subfield, the effect of reducing the reactive power by stopping the drive waveform is great. For example, when a video signal composed of a combination of black display whose gradation level is 0 and white display whose gradation level is the maximum gradation level is input, the ratio of the white display area to the entire display area is sub It becomes equal to the display rate of the field SF8. Accordingly, when a video signal composed of a combination of white display and black display is input, the drive waveform is stopped when the ratio of the white display area to the entire display area is greater than 1.0%, and the entire display area is displayed. When the ratio of the white display area is 1.0% or less, a drive waveform is input. On the other hand, when the number of subfields for performing the process of stopping the drive waveform increases, the process becomes complicated, the circuit scale increases, and the cost increases. Therefore, by setting the threshold value of the display rate only for the upper subfield in this way, it is possible to improve the reduction effect of reactive power by an easy process without increasing the circuit scale.

  FIG. 6 (E) is a modification of FIG. 6 (D) in which the threshold value of the display rate is set in a specific subfield. In FIG. 6E, the threshold of the display rate is set to 0.5% for the uppermost subfield SF8, and the threshold of the display rate is set to 2.0% for the subfield SF7. Also in this case, when the input video is a combination of white display and black display, the drive waveform may be controlled so that the ratio of the white display area to the total display area is the display ratio of the subfields SF7 and SF8. Compared with FIG. 6D, the threshold value of the subfield SF8 is set low and the threshold value of the subfield SF7 is set high while preventing the deterioration of the image quality due to the loss of the information of the subfield with the highest luminance. The reduction effect of reactive power is improved. In this way, it is also effective to switch and optimize the threshold setting according to the video characteristics.

  When video data composed only of cells of the maximum gradation level in which all the subfields are lit and cells of the minimum gradation level in which all the subfields are not lit, is input. Control for stopping the output of the drive waveform may be performed using the ratio of the number of cells at the maximum gradation level as the display rate of each subfield.

  As described above, according to the first embodiment, when it is determined that the display rate in the subfield is equal to or less than the set threshold, the subfield is turned off and the plasma display panel 114 is driven. By stopping the waveform output, reactive power can be reduced.

(Second Embodiment)
Next, a second embodiment of the present invention will be described.
In the first embodiment, the example in which the drive waveform is stopped without reconstructing the video information has been shown. However, an example in which the video data is reconstructed in order to prevent deterioration of the image quality is illustrated in FIGS. 8 will be used for explanation. 7 and 8 show an example of a lighting table (subfield lighting pattern) when one field includes eight subfields SF1 to SF8 and output of the drive waveform in the subfield SF6 is stopped.

  FIG. 7 is a lighting table for outputting drive waveforms in all of the subfields SF1 to SF8 (applied before stopping the output of drive waveforms in the subfield SF6). FIG. 8A shows the subfields. It is a lighting table for outputting drive waveforms in subfields SF1 to SF5, SF7, and SF8 excluding SF6. In the examples shown in FIGS. 7 and 8, it is assumed that luminance weights are given to the subfields as shown.

  In the display of video data, when it is determined that the display rate of the subfield SF6 is equal to or less than the threshold as a result of the determination relating to the display rate for each subfield in the display rate determination unit 70 for each subfield in FIG. The lighting table shown in FIG. 8A is used instead of the lighting table shown in FIG. As a result, video data that should originally be lit in the subfield SF6 is assigned to the subfields SF5 and SF7 by processing such as error diffusion. Compared with the lighting table shown in FIG. 7, the number of gradations that can be directly output is smaller in the lighting table shown in FIG. 8A, but the error is reduced while stopping the output of the drive waveform and reducing the reactive power. Image quality deterioration can be suppressed by diffusion processing, dither processing, or the like. The process of switching the lighting table is performed by giving a command to the non-linear gain conversion unit 20 so that the non-linear parameter determination unit 100 in FIG. 1 performs non-linear conversion of the input signal to the luminance corresponding to the lighting pattern of the switched subfield.

  FIG. 8B shows the relationship between the display rate of the subfield and the output state of the drive pulse when the video data is reconstructed using the lighting table shown in FIG. Before the video data is reconstructed by applying the video data conversion process, display is performed using the lighting table of FIG. 7, and the display rate of the subfield SF6 is 4%. On the other hand, after the video data conversion processing is performed, display is performed using the lighting table of FIG. 8A, so that the video data of the subfield SF6 is distributed to the subfields SF5 and SF7, and the subfield SF5, The display rate of SF7 is increased by 2%, and the display rate of subfield SF6 is 0%. For the subfields SF6 and SF8 in which the display rate of the subfield is 0%, the drive pulse output is stopped and is not lit. By reconstructing the video data, image quality deterioration can be suppressed as compared with the case where the subfield SF6 is simply not turned on, and the reactive power can be reduced while minimizing the image quality deterioration.

  As described above, according to the second embodiment, the subfield is turned off by allocating the video data that should have been lit in the subfield where the output of the drive waveform is stopped to the upper and lower subfields. It is possible to reduce power consumption by suppressing image quality degradation due to the above.

(Third embodiment)
Next, a third embodiment of the present invention will be described.
First, how to change the threshold value of each subfield when the condition changes will be described with reference to FIGS. Next, with reference to FIG. 15, description will be given from which point the drive waveform of the next subfield is applied when the drive waveform is stopped.

  The plasma display device according to the third embodiment can change the threshold of the display rate according to the operation state of the plasma display device and the image to be displayed.

  FIG. 9 is a block diagram illustrating a configuration example of the plasma display device according to the third embodiment. In FIG. 9, the same components as those shown in FIG. 1 are denoted by the same reference numerals, and redundant description is omitted. As shown in FIG. 9, the plasma display device in the third embodiment has a histogram detection unit 120 and a determination threshold value setting unit 130 in addition to the plasma display device in the first embodiment shown in FIG. .

  The histogram detection unit 120 detects, for each field, a histogram related to the tone distribution of the video signal based on the video signal that has been inverse gamma converted by the inverse gamma conversion unit 10.

  The determination threshold setting unit 130 displays the display rate based on the display rate for each subfield detected by the display rate detection unit 50 for each subfield and the histogram related to the gradation distribution of the video signal detected by the histogram detection unit 120. Determine the threshold. Further, the determination threshold setting unit 130 supplies the determined display rate threshold to the subfield display rate determination unit 70 and sets it.

  The determination threshold value setting unit 130 determines the display rate threshold value by providing a threshold value table and selecting the display rate according to the input display rate, a histogram related to the gradation distribution, and the like. Anyway. Further, the threshold value may be determined based on an input display rate, a histogram related to the gradation distribution, or the like by processing using software or the like.

  As in the first embodiment, when the display rate of a subfield is determined to be equal to or less than a set threshold, the plasma display device in the third embodiment turns off the subfield and plasma The output of the drive waveform of the display 114 is stopped, and the reactive power is reduced. Further, the video data corresponding to the non-lighted subfield is allocated to the adjacent upper / lower subfields to suppress image quality degradation, and to reduce reactive power while minimizing image quality degradation. In the plasma display device according to the third embodiment, the threshold of the display rate can be dynamically changed according to the operation state of the plasma display device and the image to be displayed, and control related to the stop of output of the drive waveform is performed according to the operation state and display. Appropriately depending on the image or the like, it is possible to further improve the reactive power reduction effect.

  As an example, according to each of (a) the gradation distribution of the video signal, (b) the display load factor of the video signal, (c) the display rate of the adjacent subfield, and (d) the operating state of the plasma display device. A case where the display rate threshold is changed will be described. In the example described below, it is assumed that the display rate threshold value of each subfield is 1.0% under a standard state.

(A) When changing the threshold value of the display ratio according to the gradation distribution of the video signal The distribution of the gradation distribution of the video signal is high in frequency on the high gradation side, that is, the video data is concentrated on the high gradation side. (FIG. 10A), even if information on the low gradation side is deleted, the image quality degradation caused by the information is not noticeable in the displayed video. On the other hand, when the distribution of the gradation of the video signal is such that the frequency of occurrence is high on the low gradation side, that is, when the video data is concentrated on the low gradation side (FIG. 11A), the low gradation If the information on the side is lost, the image quality degradation caused by the information is conspicuous in the displayed video. 10B and 11B, the display ratios of the subfields in the normal gradation distribution (gradation distribution in which video data is not concentrated on either the high gradation side or the low gradation side) are shown. The threshold of the display rate of each subfield compared with the threshold (FIG. 5) is shown.

  Therefore, as shown in FIG. 10A, for example, when the gradation distribution of the video signal is distributed with a frequency of 50% or more in gradations of 70% or more of the maximum gradation, FIG. As shown in (B), the thresholds of the display ratios of the lower subfields (subfields with small luminance weights) SF1, SF2, and SF3 are set to gradations in which the gradation distribution of the video signal is 70% or more of the maximum gradation. Is larger than the threshold value (FIG. 5) in the case of distribution with a frequency of less than 50%. On the other hand, as shown in FIG. 11A, when the gradation distribution of the video signal is distributed at a frequency of 50% or more in gradations equal to or less than 30% of the maximum gradation, FIG. As shown in B), the thresholds of the display ratios of the lower subfields (subfields with small luminance weights) SF1, SF2, and SF3 are set to gradations so that the gradation distribution of the video signal is equal to or less than 30% of the maximum gradation. It is made smaller than the threshold value (FIG. 5) in the case of distribution with a frequency of less than 50%. Here, the lower subfields are subfields SF1, SF2, and SF3. However, only subfield SF1 may be used, or subfields SF1 to SF7 may be used.

  In this way, by setting the threshold of the display rate according to the gradation distribution of the video signal, it is possible to appropriately stop the output of the drive waveform and reduce reactive power according to the video while suppressing image quality deterioration. Can be made.

(B) When changing the threshold of the display rate according to the display load factor of the video signal The display load factor of the video signal is a display load factor of one field. Here, the threshold of the display rate when the display load factor shown in FIG. In a video with a high display load factor of the video signal, since it is difficult to stand out even if the lower-side subfield (subfield with a small luminance weight) is not lit, for example, when the display load factor of the video signal is 60% The display rate threshold of the lower subfields (SF1, SF2, SF3) is increased as shown in FIG. 12B, compared to the case where the signal display load factor is 20%. As a result, it is possible to increase the probability that the output of the drive waveform is stopped, and to improve the reduction effect of reactive power while suppressing image quality deterioration.

(C) When changing the threshold of the display ratio according to the display ratio of the adjacent subfield For a specific subfield, the display ratio in the adjacent subfield is high, and the display in that specific subfield When the rate is low, the display rate on both sides is high, so that it is difficult to stand out even if a specific subfield between them is turned off. Therefore, as shown in FIG. 13B, the threshold value of the display rate of the subfield SF2, which is a subfield (subfield SF1, SF3 in the illustrated example) where the display rates of the adjacent subfields on both sides are both 90%. In the case of FIG. 13 (A) (when the display rates of the adjacent subfields on both sides are both 50%). Accordingly, it is possible to increase the probability that the output of the drive waveform is stopped in the subfield where the display ratios of the adjacent subfields on both sides are high, and to improve the reduction effect of reactive power while suppressing the image quality deterioration.

(D) When changing the threshold of the display rate according to the operation state (power setting) of the plasma display device The operation of the plasma display device operates in the low power consumption mode in which the power consumption is set lower than that in the normal operation state. If priority is given to reduction of power consumption by reduction of reactive power over image quality deterioration, as shown in FIG. 14B, the threshold of the display rate of the subfield is set to the normal operation shown in FIG. Make it larger than in the situation. Thereby, the probability that the output of the drive waveform is stopped in all the subfields in the field can be increased, and the effect of reducing the reactive power can be improved.

  In addition to the operating state (power setting) of the plasma display device, the threshold value of the display rate may be changed by detecting external light. When the room is bright, it is difficult to see the image due to the reflection of the panel of outside light, so it is necessary to suppress the deterioration of the image quality. On the other hand, when the room is dark, the contrast of the video is high, so even if the drive waveform is stopped, there is little influence on the viewer. Therefore, for example, when the outside light value is large and the room is bright, the threshold value of the display rate is set lower than when the detected outside light value is small and the room is dark. Accordingly, it is possible to improve the effect of reducing reactive power without suppressing the image quality degradation when the room is bright and without the viewer recognizing the degradation of the image quality when the room is dark.

  In the above description, the case where the threshold value of the display rate is changed according to each factor has been described. However, the threshold value of the display rate may be changed according to a plurality of factors by appropriately combining them. Moreover, further improvement of the reduction effect of reactive power can be expected by extremely fine control.

  As described above, according to the third embodiment, when it is determined that the display rate of the subfield is equal to or less than the set threshold, the subfield is turned off and the output of the drive waveform is stopped. Thus, reactive power can be reduced. Also, by assigning the video data that should have been lit in the subfield where the output of the driving waveform is stopped to the upper and lower subfields, it is possible to suppress image quality deterioration due to the non-lighting of the subfield. . In addition, since the threshold of the display rate can be changed according to the operating state of the plasma display device and the image to be displayed, the control for stopping the output of the drive waveform is appropriately performed according to the operating state and the display image, etc. Can be reduced.

  In each of the above-described embodiments, when outputting the drive waveform of the plasma display panel 114 is stopped, there are a method of outputting the drive waveform of the next subfield immediately and a method of providing a pause period for the stopped portion. For example, when the driving pulse in the reset period, the address period, and the sustain period is stopped and no pause period is provided, the subfield disappears. That is, when stopping all the drive pulses in the subfield SF6, the subfield SF7 follows immediately after the subfield SF5. In this case, the time for one field can be shortened, but the emission center of gravity of the subfield is shifted. For example, when the drive pulse stop target portion in the normal drive waveform shown in FIG. 15A is deleted as shown in FIG. 15B, the temporal emission position shifts in the subfields after the next subfield. Flicker may occur. Therefore, in each of the above-described embodiments, when the output of the drive pulse stop target portion shown in FIG. 15A is stopped, a pause period is provided as shown in FIG. Regardless of whether to stop or not, the next subfield is started at the same timing. As a result, it is possible to prevent the occurrence of flicker due to a temporal shift in the light emission position, and to suppress image quality deterioration.

  4B and 4D, the drive waveform output is stopped not only when the display waveform of the subfield is equal to or lower than the threshold value but when the drive waveform is stopped. You may apply when stopping. This point is not disclosed in Patent Documents 1 and 2, and the effect of the present invention that suppresses the influence on the image quality can be obtained by setting various targets of the driving waveform to be stopped.

  Each of the embodiments described so far is merely an example of implementation in carrying out the present invention, and the technical scope of the present invention should not be construed in a limited manner. is there. That is, the present invention can be implemented in various forms without departing from the technical idea or the main features thereof. Moreover, you may implement this invention by combining the said embodiment.

It is a figure which shows the structural example of the plasma display apparatus in 1st Embodiment. It is a figure which shows an example of the drive waveform (normal time) of the plasma display apparatus in 1st Embodiment. It is a figure for demonstrating the operation example of the plasma display apparatus in 1st Embodiment. It is a figure which shows an example of the drive waveform of the plasma display apparatus in 1st Embodiment. It is a figure which shows the example of a setting of the threshold value of the display rate in 1st Embodiment. It is a figure which shows the other example of a setting of the threshold value of the display rate in 1st Embodiment. It is a figure which shows an example of the lighting table of the plasma display apparatus in 1st Embodiment and 2nd Embodiment. It is a figure which shows an example of the lighting table and operation example of the plasma display apparatus in 2nd Embodiment. It is a figure which shows the structural example of the plasma display apparatus in 3rd Embodiment. It is a figure which shows the example of a setting of the threshold value of the display rate according to the gradation distribution of the video signal in 3rd Embodiment. It is a figure which shows the other example of a threshold value of the display rate according to the gradation distribution of the video signal in 3rd Embodiment. It is a figure which shows the example of a setting of the threshold value of the display rate according to the display load factor in 3rd Embodiment. It is a figure which shows the example of a setting of the threshold value of the display rate according to the display rate of the adjacent subfield in 3rd Embodiment. It is a figure which shows the example of a setting of the threshold value of the display rate according to the operation state in 3rd Embodiment. It is a figure which shows the drive waveform example at the time of the output stop of the drive waveform in each embodiment. It is a figure showing the flowchart of the operation | movement in each embodiment. It is a figure which shows an example of the drive circuit in each embodiment.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 Inverse gamma conversion part 20 Nonlinear gain conversion part 30 Error diffusion process part 40 Subfield data storage part 50 Subfield display rate detection part 60 Sustain pulse number setting part 70 Subfield display rate determination part 80 Drive pulse stop part 90 Control Signal generation unit 100 Nonlinear parameter determination unit 111 Address electrode drive circuit 112 Sustain electrode drive circuit 113 Scan electrode drive circuit 114 Plasma display panel 115 Control circuit 120 Histogram detection unit 130 Determination threshold setting unit

Claims (28)

A method of driving a plasma display apparatus, wherein one frame of video is displayed by a plurality of subfields, a sustain pulse is applied to at least one subfield of the plurality of subfields, and a cell is lit.
A driving method of a plasma display device, wherein application of at least a part of a sustain pulse is stopped in the subfield when a display rate, which is a ratio of cells lit in the subfield, is equal to or less than a threshold value. A driving method of a plasma display device according to claim 1,
A driving method of a plasma display apparatus, wherein a threshold value in the first subfield is higher than a threshold value in a second subfield having a smaller number of sustain pulses than the first subfield. A driving method of a plasma display device according to claim 1,
A driving method of a plasma display device, wherein a threshold value in the first subfield is higher than a threshold value in a second subfield having a larger number of sustain pulses than the first subfield. A driving method of a plasma display device according to claim 1,
When the display load factor, which is the ratio of the average gray level to the maximum gray level in the image of one frame, is the first ratio, the threshold is the second ratio, which is lower than the first ratio. The method of driving a plasma display device, wherein the threshold value is higher than the threshold value. A driving method of a plasma display device according to claim 1,
When the display load factor, which is the ratio of the average gray level to the maximum gray level in the image of one frame, is increased as compared with the previous frame, the threshold value of some of the subfields is set to the display load factor. A method for driving a plasma display device, characterized in that the plasma display device is made higher than before the increase. A driving method of a plasma display device according to claim 5,
The driving method of the plasma display apparatus, wherein the number of sustain pulses is smaller in some of the subfields that increase the threshold than in other subfields. A driving method of a plasma display device according to claim 1,
A driving method of a plasma display device, wherein the threshold value changes from the threshold value set in the previous frame when the gradation distribution of the image of one frame changes compared to the previous frame. A driving method of a plasma display device according to claim 7,
When the gradation distribution of the input video data is the first gradation distribution that is distributed at a frequency of 50% or more to the gradation of 70% or more of the maximum gradation, 50 to the gradation of 70% or more of the maximum gradation. A driving method of a plasma display device, characterized in that the threshold value is increased in at least one subfield as compared with the case of the second gradation distribution distributed at a frequency of less than%. A driving method of a plasma display device according to claim 7,
When the gradation distribution of the input video data is the first gradation distribution that is distributed at a frequency of 50% or more in the gradation that is 30% or less of the maximum gradation, the gradation is 50 in the gradation that is 30% or less of the maximum gradation. A driving method of a plasma display device, wherein the threshold value is lowered in at least one subfield as compared with the case of the second gradation distribution distributed with a frequency of less than%. A driving method of a plasma display device according to claim 1,
When there is a first setting and a second setting that is a setting that reduces the power consumption of the plasma display device than the first setting, the second setting is higher than the threshold value in the first setting. A driving method of a plasma display device, characterized by increasing a threshold value. A driving method of a plasma display device according to any one of claims 1 to 10,
A driving method of a plasma display device, wherein application of at least a part of a sustain pulse is stopped by fixing or interrupting a voltage supplied to the cell. An image of one frame is displayed by a plurality of subfields, and at least one of the plurality of subfields is selected by a reset period for initializing cells, an address period for selecting cells to emit light, and the address period. A driving method of a plasma display device comprising a sustain period for emitting light from a cell,
When the input video is a combination of a cell area that is black and a cell area that is white, the first subfield having the largest number of sustain pulses among the plurality of subfields A sustain pulse is not applied when the ratio to the entire display area is the first ratio, and the sustain pulse is applied when the ratio of the white display area to the entire display area is a second ratio higher than the first ratio. Is applied to the plasma display device. A driving method of a plasma display device according to claim 12,
A driving method of a plasma display apparatus, wherein a sustain pulse is applied to a subfield other than the first subfield regardless of a ratio of the white display area to the entire display area. A driving method of a plasma display device according to claim 12,
In the second subfield having the second largest number of sustain pulses among the plurality of subfields, a sustain pulse is not applied when the ratio of the white display area to the entire display area is the second ratio, A driving method of a plasma display apparatus, wherein a sustain pulse is applied when a ratio of a white display area to a total display area is a third ratio higher than the second ratio. The method of driving a plasma display device according to claim 14,
A driving method of a plasma display apparatus, wherein a sustain pulse is applied to a subfield other than the first subfield and the second subfield regardless of a ratio of the white display area to the entire display area. A method for driving a plasma display device according to any one of claims 12 to 15,
The method of driving a plasma display apparatus, wherein a portion of a sustain pulse is not applied when the ratio of the white display area to the entire display area is the first ratio in the first subfield. A plasma display panel comprising an address electrode and a sustain electrode and a scan electrode crossing the address electrode;
A first driving circuit for supplying a driving voltage to the address electrodes;
A second drive circuit for supplying a drive voltage to the sustain electrode;
A third drive circuit for supplying a drive voltage to the scan electrode;
A plasma display device comprising: a control circuit that controls at least one of the first drive circuit, the second drive circuit, and the third drive circuit;
The control circuit supplies to the plasma display panel in the subfield when the display rate, which is the ratio of the cells that are turned on in the subfield to the cells constituting one screen when the input signal is subfield converted, is equal to or less than a threshold value. A plasma display device, wherein at least one of the first drive circuit, the second drive circuit, and the third drive circuit is controlled so that a drive voltage is fixed or cut off during a predetermined period. The plasma display device according to claim 17,
The control circuit controls at least one of the first drive circuit, the second drive circuit, and the third drive circuit so that the drive voltage is fixed or cut off during a sustain period in which the plurality of cells are turned on. A plasma display device. The plasma display device according to claim 18, wherein
The control circuit includes the first driving circuit, the second driving circuit, and the second driving circuit so as to fix or cut off at least the driving voltage in a sustain loop period excluding a pre-processing period and a post-processing period in which charge adjustment is performed in the sustain period. A plasma display device that controls at least one of the driving circuit and the third driving circuit. The plasma display device according to any one of claims 17 to 19,
The control circuit controls at least one of the first drive circuit, the second drive circuit, and the third drive circuit so as to fix or cut off the drive voltage in an address period for selecting a cell to be lit. A plasma display device. The plasma display device according to any one of claims 17 to 20,
The control circuit includes at least one of the first drive circuit, the second drive circuit, and the third drive circuit so that the drive voltage is fixed or cut off during an on-cell reset period in which a lit cell is initialized. A plasma display device characterized by controlling one. The plasma display device according to claim 21, wherein
The control circuit includes the first drive circuit, the second drive circuit, and the third drive circuit so as to fix or cut off the drive voltage during an all-cell reset period in which cells constituting one screen are initialized. A plasma display apparatus that controls at least one of the above. The plasma display device according to any one of claims 17 to 22,
The control circuit displays the first drive circuit, the second drive circuit, and the third drive circuit so that video data displayed in a subfield whose display rate is equal to or less than a threshold value is displayed in another subfield. A plasma display apparatus that controls at least one of the above. The plasma display device according to any one of claims 17 to 23,
The plasma display apparatus, wherein the control circuit performs an error diffusion process for diffusing an error between a gradation level of an input video signal and a gradation level displayed in a cell to another cell. The plasma display device according to any one of claims 17 to 24,
The control circuit controls at least one of the first drive circuit, the second drive circuit, and the third drive circuit so as to provide a pause period until the voltage is supplied in the next subfield. A plasma display device. The plasma display device according to claim 25, wherein
When the display rate of the subfield is less than or equal to a threshold value, the control circuit is configured so that the start timing of the subsequent subfield does not change from that when the display rate of the subfield is greater than the threshold value. A plasma display device that controls at least one of the second drive circuit and the third drive circuit. The plasma display device according to any one of claims 17 to 26,
The control circuit is configured to fix or cut off the driving voltage supplied to the plasma display panel in a sustain loop period excluding a pre-processing period and a post-processing period in which charge adjustment is performed in a sustain period. A plasma display device that controls at least one of a drive circuit, the second drive circuit, and the third drive circuit. The plasma display device according to any one of claims 17 to 27,
The plasma display apparatus, wherein the second drive circuit is common to the third drive circuit.

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