JP2005275048A - Display device and display control method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To suppress luminance change of a still image to switching of emission systems by luminance change of a moving image in the case of displaying the moving image together with the sill image in an image display device having a plasma AI function which is executed especially suitable for a spontaneous display panel such as a plasma display panel and an organic EL panel and constituted so as to suppress an amount of power consumption of a panel by emitting each pixel for a plurality of times in one field, displays gradation with this emission frequency, predicting the amount of power consumption of the panel per unit area from an inputted video signal and switching the emission systems (the total emission frequencies in one field) to be applied to the whole panel from its predicted value. <P>SOLUTION: The amount of power consumption of the panel per unit area is predicted separately from inputted video signals Rsp, Gsp, Bsp of the still image, and a multiplication factor corresponding to ratio of the total emission frequencies of an emission system corresponding to its prediction result and an actual emission system is multiplied to the video signals Rsp, Gsp, Bsp. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a display device and a display control method suitable particularly when a self-luminous display panel such as a plasma display panel, an organic EL panel, or a light emitting diode panel is used.

  In particularly self-luminous display panels such as the plasma display panel, organic EL panel, and light emitting diode panel, the power consumption of the light emitting element is proportional to the luminance. However, in realizing gradation expression, it is very difficult to control the current value. Therefore, conventionally, each pixel of the display panel emits light a plurality of times within one field, and gradation display is performed by the number of times of light emission. Things have been done.

  On the other hand, in the display panel as described above, when the luminance level of the video signal to be displayed increases, problems such as panel burn-in and the power consumption of the entire image display device exceed the specified rated power consumption. Therefore, in order to solve such a problem, as a typical conventional technique, Patent Document 1 discloses that an automatic power control (APC) unit displays a display panel according to a change in the average luminance signal level of an input video signal. A technique called so-called plasma AI is disclosed in which the amount of light emission (luminance) per unit area is adjusted so that power consumption does not become too large.

  However, the luminance signal is determined in accordance with the ratio that the human eye feels brightness, and is not proportional to the power consumption of the display panel, that is, the luminance. For example, assuming that a commonly used conversion formula Y = 0.3R + 0.59G + 0.11B is used in a Y encoding circuit, red (hereinafter referred to as R), green (hereinafter referred to as G), blue (hereinafter referred to as R). , B) when displaying a single color (YR: luminance signal when displaying a red color, YG: luminance signal when displaying a green color, YB: when displaying a blue color) The ratio of luminance signal) is YR: YG: YB = 0.3: 0.59: 0.11, and the luminance signal YG when humans display sensitive G is the largest, and insensitive B is displayed. The luminance signal YB signal is set to be the smallest.

  Therefore, when the light emission amount is adjusted according to the average luminance Y in the automatic power control unit, when the image has more green components than the other colors, the influence of the luminance signal YG when the green single color is displayed with respect to the average luminance Y. Since the amount of light emitted from the display panel is unnecessarily small, and the image has a larger blue component than other colors, the influence of the luminance signal YB when displaying a single blue color with respect to the average luminance Y is small. There is a possibility that the light emission amount of the panel becomes larger than necessary and exceeds the capacity of the power supply unit. As described above, there is a problem that automatic control of power consumption and light emission amount cannot be performed accurately.

  Therefore, in order to solve such a problem, Patent Document 2 has been proposed as another conventional technique. The configuration of the prior art is shown in FIG. The image display apparatus of FIG. 6 generally includes three integration circuits m1, m2, and m3 corresponding to R, G, and B colors, and three multiplication circuits k1, k2, and k3 that individually correspond to them. , An adder circuit 11, a controller 12, a delay circuit 13, three multiplier circuits k11, k12, k13, a video signal-subfield correlator 14, a subfield pulse generation circuit 15, and a scanning driver 16 The data side driver 17 and the PDP panel 18 are provided.

  The R integration circuit m1, the G integration circuit m2, and the B integration circuit m3 respectively input the R signal, the G signal, and the B signal as input video signals, integrate the signals for a specific period, for example, at least one field, The value divided by the number of integrated pixels is output as an R average level, a G average level, and a B average level.

  The R average level, G average level, and B average level obtained by each of the integration circuits m1, m2, and m3 are respectively input to the corresponding multiplication circuits k1, k2, and k3, and the coefficients are set in advance. The result is multiplied by KR, KG, and KB, and the result is output to the adder circuit 11. Here, the coefficients KR, KG, and KB are such that the ratio of these coefficients is equal to the ratio of the amount of power consumed for each color when an image of the same condition is displayed for each color of R, G, and B, respectively. Set to the correct value. That is, in the state where the power control by the controller 12 to be described later does not work, video signals of the same condition are sequentially input as R, G, B signals and consumed for data display when displayed in R, G, B single colors respectively. The power amount to be measured is measured in advance, and the ratio of the measured power amounts of the respective colors is made equal to the ratio of the coefficients KR, KG, and KB. For example, if PR is the power consumption when a certain image is displayed in red, PG is the power consumption when the same image as that image is displayed in green, and PB is the power consumption when displayed in blue, then PR: PG: The coefficients are determined so that PB = KR: KG: KB.

  Next, the multiplication circuit k1 sets the coefficient KR to the R average level from the R integration circuit m1, the multiplication circuit k2 sets the coefficient KG to the G average level from the G integration circuit m2, and the multiplication circuit k3 sets the coefficient KB to The B average level from the B integration circuit m3 is multiplied. The adder circuit 11 adds the output signals from the integrating circuits m1, m2, and m3 to each other to obtain a predicted power consumption value and outputs a power consumption prediction signal to the controller 12. In response to the power consumption prediction signal, the controller 12 adjusts the light emission amount (luminance) per unit area of the PDP panel 18 and selects a light emission format that does not cause excessive power consumption. The light emission pulse control signal corresponding to is output. At the same time, the controller 12 calculates and outputs a multiplication coefficient so that there is no difference in the amount of light emission (brightness) of the video between the different light emission formats. Details of these operations of the controller 12 will be described later.

  On the other hand, the input video signals R, G, B are also input to the delay circuit 13, respectively. The delay circuit 13 converts the input video signals R, G, B into integration circuits m1-m3 and multiplication circuits k1- k3, and the delayed video signals DR, DG, DB delayed by the total time required for the processing of each part of the adder circuit 11 and the controller 12 are output. The delayed video signals DR, DG, DB are input to the multiplication circuits k11, k12, k13, multiplied by the multiplication coefficient output from the controller 12, and output.

  The video signal / subfield correlator 14 receives the output signals of the multiplication circuits k11 to k13 and the light emission pulse control signal from the controller 12, and outputs the power of the multiplication circuits k11 to k13 expressed by a power of two. The output signal is converted into a light emission pattern having a subfield configuration corresponding to the light emission pulse control signal, and the data of the first subfield and the second subfield of each pixel are transmitted at a predetermined timing during one field period. Data..., N-th subfield data are sent in order (n is the number of subfields). Note that the video signal / subfield correlator 14 may perform predetermined processing such as conversion of the number of subfields to suppress the occurrence of pseudo contours.

  The subfield pulse generation circuit 15 receives the light emission pulse control signal as an input, and supplies a scanning, maintenance, and erasure signal to the scanning side driver 16 in a subfield configuration of a light emission format according to the light emission pulse control signal. The scanning driver 16 supplies scanning, maintenance, and erasing signals to each row electrode of the PDP panel 18 at a predetermined voltage level.

  On the other hand, the data side driver 17 receives an output signal from the video signal / subfield associator 14 and generates an image data pulse having a voltage value corresponding to each pixel data, and outputs this image data pulse for each column. And is supplied to the column electrodes of the PDP panel 18 in synchronization with the signal output from the scanning driver 16. The PDP panel 18 can actually emit light when a light emission pulse is input from the scanning side driver 16 and the light emission pulse supplied from the data side driver 17 is active. In this way, the PDP panel 18 is driven, and images corresponding to the input video signals R, G, and B are displayed. In the multiplication circuits k1, k2, and k3, the average levels of the input video signals R, G, and B are multiplied by coefficients KR, KG, and KB, respectively, and then added to each other, whereby the input video signals R, It is possible to control power consumption and light emission (brightness) that are not affected by the hues of G and B.

  By the way, as described above, this image display device can reduce the power consumption even when the input video signals R, G, and B change, the amount of information to be displayed increases and the power consumption increases. The light emission amount / brightness of the PDP panel 18 is controlled so as to be limited within a certain range. That is, the light emission format (light emission time and the number of times of light emission) and the gradation of the display image are controlled so that the power consumption during image display does not exceed a certain reference value P. For this reason, the power consumption amount is predicted based on the input video signals R, G, and B, and the light emission format (so that the power consumption amount is limited within a predetermined range based on the predicted power consumption amount. (Light emission time and number of times of light emission) and gradation are controlled. Specifically, the controller 12 selects the light emission format according to the value of the power consumption prediction signal, the light emission pulse control signal for controlling the light emission format, and the light emission amount / luminance in the PDP panel 18 between different light emission formats. The multiplication coefficient for adjusting the gradation level of the delayed video signals DR, DG, and DB is output so that.

  Hereinafter, a method of determining the light emission format and the multiplication coefficient in the controller 12 will be described. First, the light emission format will be described. In the present image display device, the total number of times of light emission (maximum number of times of light emission) allowed within one frame period is 1275, 1020, 765, 510, as the value of the power consumption prediction signal increases as shown in FIG. It has five light emission formats A, B, C, D, and E that are as small as 255.

  On the other hand, the input video signals R, G, and B are expressed by gradation levels of 8-bit gradation from 0 to 255, and the light emission format E is equal to the gradation level (1 time). On the other hand, light emission format A emits light 5 times the gradation level, light emission format B emits 4 times the gradation level, and light emission format C and light emission format D emit light 3 times or twice the gradation level. The number of light emission pulses is set so that it can be performed. These light emission formats A to E are switched based on the power consumption prediction signal.

  First, a power consumption prediction signal value (hereinafter referred to as “switching point”) at which the light emission format is switched will be described. FIG. 8 is a diagram for explaining a method of determining the switching point of the light emission format, and is a diagram showing the relationship between the power consumption prediction signal and the amount of power consumed for display. As shown in FIG. 8, the power consumption prediction signal values of the light emission format A and the light emission format B are the switching point TB, the light emission format B and the light emission format C are the switching point TC, and the light emission format C and the light emission format D. Is the switching point TD, and the light emission format D and the light emission format E are switched at the switching point TE. The switching point TE can be obtained, for example, as follows.

  That is, the input video signals R, G, and B are changed so that the power consumption prediction signal gradually decreases from the maximum, and the power consumption at that time is measured. At this time, the power consumption prediction signal is obtained with a multiplication coefficient of 1. As the power consumption prediction signal decreases, the actual power consumption also decreases, and the value of the power consumption prediction signal when the power consumption reaches the reference value P is set as the switching point TE. Since the total number of times of light emission of the light emission format D is twice the total number of times of light emission of the light emission format E, if the power consumption prediction signal is displayed in the light emission format D when the power consumption prediction signal is TE, the power consumption is 2P. Using this point as a starting point, the power consumption prediction signal is gradually decreased in the same manner as described above, and the power consumption prediction signal value TD with the power consumption amount P is obtained. Thereafter, the switching points TC and TB can be obtained in the same manner.

  On the other hand, when the power consumption prediction signal is changed, if only the light emission format having a different light emission number is simply switched with respect to the signal of the same gradation level, the difference in the light emission number in the PDP panel 18 when switching. Appears as a luminance difference. For this reason, as described above, it is necessary to adjust the gradation levels of the input video signals R, G, and B so that the light emission amount and the luminance transition smoothly. Further, as shown in FIG. 8, the amount of power consumed for data display greatly exceeds the reference value P. Accordingly, the controller 12 outputs the multiplication coefficient that changes according to the power consumption prediction signal, and multiplies the delayed video signals DR, DG, and DB in the multiplication circuits k11, k12, and k13, thereby actually displaying the gradation to be displayed. Is corrected. That is, the number of times of light emission corresponds to the input video signals R, G, and B.

  For example, the relationship between the predicted power consumption value and the light emission format is shown in FIG. 9A in the above-described case. The power consumption prediction signal changes, and the light emission format A is changed to the light emission format B at the switching point TB. When the light emission format changes, for signals of the same gradation level, (luminance in light emission format A): (luminance in light emission format B) = (number of times of light emission in light emission format A): (light emission format) B)) = 5: 4, the multiplication coefficient in the light emission format A is 1 when the power consumption prediction signal is small as shown in FIG. 9B, and the power consumption prediction signal is large. As it becomes, it is set so as to decrease monotonously. At the switching point TB, 4/5 = 0.8. In this case, for example, when the gradation level of the input video signals R, G, and B is 200, the gradation level is 200 × 0.8 in the light emission format A, and therefore 200 × 0.8 × 5 = 800 times of light emission. In the light emission format B, 200 × 4 = 800 times remains, and the luminance in the PDP panel 18 can be made equal between the light emission formats A and B.

  Regarding the change of other light emission formats, the setting of the multiplication coefficient is the same, and as the power consumption prediction signal increases, 1 to 0.75 (3/4) in the light emission format B and 1 to 0 in the light emission format C. .67 (2/3) and 1 to 0.5 (1/2) in the light emission format D. By setting the multiplication coefficient in this way, as shown in FIG. 9C, even when the light emission format is switched, the light emission amount and the luminance are smoothly changed so that the luminance difference is not detected in the PDP panel 18. be able to.

Here, for simplification of explanation, when TB = 0.2, TC = 0.4, TD = 0.6, TE = 0.8, the power consumption prediction signal value is x, and the multiplication coefficient is y. The relationship is as follows.
Light emission type A ... y = -x + 1 (x <0.2) (1)
Light emission type B ... y = -5 / 4 · x + 5/4 (0.2 ≦ x <0.4) (2)
Light emission type C ... y = -5 / 3 · x + 5/3 (0.4 ≦ x <0.6) (3)
Light emission type D ... y = −5 / 2 · x + 5/2 (0.6 ≦ x <0.8) (4)
Emission type E ... y = ax + (1-0.8a) (0.8 ≦ x) (5)

Thus, by obtaining the multiplication coefficient in accordance with the power consumption prediction signal in the controller 12, the change in the power consumption with respect to the power consumption prediction signal is as shown in FIG. 9D from the characteristics shown in FIG. Characteristics. Thus, regardless of the input video signals R, G, and B, the amount of power consumed for data display does not significantly exceed the reference value P.
JP-A-8-65607 Japanese Patent Laid-Open No. 13-22318

  However, in the above-described conventional technology, the predicted power consumption value is a predicted value of the total power consumption obtained by integrating the input video signals R, G, and B in the entire area of the PDP panel 18 by at least one field. Therefore, for example, as shown in FIG. 10, a still image is displayed as a moving image so as to be conspicuous in a blank portion due to a difference between the screen size (aspect ratio) of the PDP panel 18 and the screen size of the input video signals R, G, B. When the display is also displayed, if the level of the input video signal in the moving image region changes and the light emission format is switched, there is a problem that the level of the still image changes following that. FIG. 10 shows an example in which a video signal having an aspect ratio of 4: 3 is input to a display panel having an aspect ratio of 16: 9. The black part.

Describing in detail with reference to FIG. 10, for example, when the gradation level of the input video signals R, G, B is 10 in the side frame 2 and 100 is the peak pixel in the moving image area 1, FIG. As shown in FIG. 10 (a), when the pattern in the moving image area 1 is generally dark and the light emission format determined based on the predicted value of the total power consumption is A, the total light emission number (maximum light emission number) is The peak luminance at this time is 500 cd / m ² . Therefore, in the side frame 2 portion, the number of times of light emission is 50 times, and the luminance is 50 cd / m ² .

On the other hand, as shown in FIG. 10B, when the pattern in the moving image area 1 becomes generally brighter and the light emission format determined based on the predicted value of the entire area power consumption becomes D, the total light emission The number of times is doubled to 200 times, and the peak luminance is 200 cd / m ² . At this time, in the side frame 2 portion, the number of times of light emission is 20, and the luminance is 20 cd / m ² . As described above, when the level of the input video signal in the moving image area 1 is changed and the light emission format is switched, the level of the still image is changed accordingly. Note that if the gradation level of the side frame 2 portion that becomes a black solid screen is 0, the luminance level can be kept unchanged even when the light emission format of the moving image area 1 is changed. Since panel burn-in occurs, data of some low gradation level is given.

  In addition to the above, as shown in FIG. 11A, conversely, when a signal with a screen size of 16: 9 is input to a display panel with a screen size of 4: 3, the margins due to the upper and lower frames ( In FIG. 11A, two screens are displayed side by side in the video section), a solid screen portion such as a background, and the sub image is aligned with the main image as shown in FIG. 11B. If you want to superimpose the time, etc. on the margins, and even the television image, or display the computer data on a part of the display panel, add the sub image to the main image. When displaying together, the same applies.

  An object of the present invention is to stabilize the luminance of a blank portion due to a difference between the screen size of the display panel and the screen size of an input video signal or a solid screen portion such as a background, and improve the display quality. And a display control method.

  In the display device of the present invention, the prediction unit predicts the power consumption of the display panel from the input video signal, and the light emission control unit suppresses the power consumption to a predetermined level according to the prediction result. In the display device that performs light emission control, when displaying the sub-image together with the main image, the prediction unit also predicts the power consumption amount in the sub-image area from the input video signal, and the light emission control unit In response to the prediction result of the prediction means, the power consumption in the sub-image area is individually controlled.

  According to said structure, it implements suitably for especially display panels of self-light-emission, such as a plasma display panel and an organic electroluminescent panel, and a prediction means estimates the power consumption of a display panel from an input video signal, Light emission control means However, by controlling the light emission so as to suppress the power consumption to a predetermined level according to the prediction result, the burn-in of the panel or the power consumption of the entire display device exceeds the specified rated power consumption. In a display device having a video signal processing function called a so-called plasma AI that prevents the occurrence of a sub-image such as a still image in a main image such as a moving image, The prediction means also predicts the power consumption in the sub-image area from the input video signal, and the light emission control means responds to the prediction result in the prediction means, The power consumption of the sub-image area, the control of the entire panel individually controlled.

  Therefore, even if the luminance of the main image to be displayed changes, the predicted value of the power consumption in the entire panel changes, and the control state of the light emission control changes, the power consumption in the entire panel is determined in advance. Since the power consumption amount in the sub-image area is controlled to a value suitable for the image in the sub-image area while being suppressed to the level, it is possible to eliminate the luminance change of the sub-image accompanying the luminance change of the main image. Thus, for example, a margin due to a difference between the screen size (aspect ratio) of the display panel and the screen size of the input video signal (when a signal having a screen size of 4: 3 is input to a display panel having a screen size of 16: 9). Stabilizes the brightness of the side frame and the 4: 3 screen size display panel when the 16: 9 screen size signal is input, and the solid screen portion such as the background. Can be improved.

  The sub-image is not limited to the side frame or the solid screen, but the television image as the main image is superimposed on the time as the sub-image, or the sub-image is displayed on a part of the display panel. It can also be applied when displaying computer data.

  In the display device of the present invention, the light emission control unit causes each pixel of the display panel to emit light a plurality of times within one field, performs gradation display by the number of times of light emission, and consumes the entire display panel by the prediction unit. The maximum number of times of light emission in the one field applied to the entire display panel is determined for each of the power consumption ranges depending on which of the power consumption ranges in which a plurality of types of power consumption prediction values are set. By setting the number of times set in the above, the power consumption of the display panel is suppressed to the predetermined level, and the input image signal of the sub-image area is consumed by the predicting unit. A coefficient corresponding to the ratio of the maximum number of times of light emission between the range to which the predicted amount of power belongs and the range to which the predicted power consumption of the entire display panel belongs is obtained, and the input video signal in the sub-image area is multiplied by the coefficient Characterized in that it comprises a multiplication means that.

  According to said structure, it implements suitably for the display panel of especially self-light-emission, such as the said plasma display panel and an organic electroluminescent panel, and the light emission control means makes each pixel of a display panel light-emit several times within one field, In addition to performing gradation display with the number of times of light emission, the prediction means predicts the power consumption amount of the display panel from the input video signal, and the light emission control means has a power consumption range in which a plurality of power consumption prediction values are set. The maximum number of times of light emission within one field applied to the entire display panel (the number of light emission pulses given to the scanning side driver, and the light emission pulse given from the data side driver is active) When the display panel is set to the number of times set for each power consumption range, as described above, In a display device having a video signal processing function referred to as so-called plasma AI, in which the power consumption is suppressed to a predetermined level, the light emission control means also includes power consumption of the sub-image area by the prediction means. A coefficient corresponding to the ratio of the maximum number of times of light emission between the range to which the predicted value belongs and the range to which the predicted power consumption of the entire display panel belongs is obtained, and the multiplication means multiplies the input video signal in the sub-image area.

  Therefore, even if the luminance of the main image to be displayed changes, the power consumption range to which the predicted value of power consumption belongs changes, and the maximum number of times of light emission per field applied to the entire display panel changes, The video signal in the sub-image area is multiplied by a multiplication coefficient that compensates for the change in the maximum number of times of light emission, and the number of times of light emission per field is controlled to a value suitable for the image in the sub-image area. It is possible to eliminate the luminance change of the sub-image accompanying the luminance change. In this manner, a configuration that can eliminate the luminance change of the sub-image accompanying the luminance change of the main image can be specifically realized.

  Furthermore, in the display device of the present invention, the light emission control means divides one field of the input video signal into a plurality of weighted subfields, and displays the video of each subfield in a time-overlapping manner. The gradation display is performed, and the maximum number of times of light emission is determined for each light emission type that is set according to which of the power consumption ranges in which the predicted value of the power consumption amount is set, The light emission control means outputs a light emission pulse control signal representing a set light emission format, and a video signal-subfield associating means for associating an input video signal with a subfield configuration of the light emission format corresponding to the light emission pulse control signal; In response to a light emission pulse control signal, a subfield pulse generation that generates a light emission pulse in a light emission type subfield configuration based on the light emission pulse control signal. Characterized by further comprising a means.

  According to the above configuration, in response to the light emission pulse control signal output from the light emission control means, the light emission pulse corresponding to the input video signal is generated by the video signal-subfield association means and the subfield pulse generation means. In the display device, the light emission format applied to the entire panel is switched by the luminance change of the main image, and the multiplication means for the input video signal in the sub-image area is switched even if the maximum number of times of light emission is switched. Is multiplied in advance, so that the amount of change is compensated in advance, and the luminance change of the sub-image accompanying the luminance change of the main image as described above can be eliminated.

  In the display device of the present invention, the input video signal is a full-color signal composed of R, G, and B color components, and the display panel displays the same image in each of the R, G, and B colors as a single color. The ratio of power consumed for each display and / or the area ratio of the phosphors is KR: KG: KB, and the predicting means uses the input video signal R for at least one field. , G and B are integrated to output R average level, G average level, and B average level, respectively, R integration circuit, G integration circuit, and B integration circuit, and R average level, G average level, and B average level The total power of the display panel and the sub-image area are calculated from the sum of the outputs of the first to third multiplication circuits and the first to third multiplication circuits respectively multiplying the ratios KR, KG, and KB. Power consumption of The multiplying means is configured to multiply the predetermined ratios KR, KG, KB when the input video signals R, G, B are signals in the main image area, respectively. If it is a signal in the sub-image area, it comprises fourth to sixth multiplication circuits for multiplying the coefficients obtained by the light emission control means, respectively, and the video signal-subfield association means comprises the light emission pulse. The output from the fourth to sixth multiplier circuits is associated with the subfield configuration of the light emission format corresponding to the control signal.

  According to the above configuration, using the coefficients KR: KG: KB representing the ratio of the power consumed when the three primary colors R, G, and B are displayed in a single color and / or the area ratio of each color phosphor, Since the light emission amount (brightness) and power consumption are controlled based on the total area power consumption and still image area power consumption obtained by weighting each color average level and taking the sum, the input video signals R, G, B It is possible to control power consumption and light emission (brightness) that are not affected by the color tone.

  Furthermore, the display control method of the present invention causes each pixel of the display panel to emit light a plurality of times within one field, performs gradation display at the number of times of light emission, and consumes per unit area of the display panel from the input video signal. The amount of power is predicted, and the maximum number of times of light emission within the one field applied to the entire display panel is switched so as to suppress the amount of power consumption per unit area to a predetermined level or less based on the prediction result. In the display control method described above, when a still image is displayed together with a moving image, the still image area prohibits a change in the number of times of light emission associated with the switching of the maximum number of times of light emission.

  According to the above configuration, the present invention is preferably applied to a self-luminous display panel such as a plasma display panel or an organic EL panel, and each pixel of the display panel emits light a plurality of times within one field, and gradation is determined by the number of times of light emission. The display unit 1 is applied to the entire display panel so as to predict the power consumption of the display panel from the input video signal and suppress the power consumption to a predetermined level or less from the prediction result. By switching the maximum number of times of light emission in the field, it is called so-called plasma AI, etc., which prevents the burn-in of the panel and the power consumption of the entire display device from exceeding the specified rated power consumption. In the display control method for realizing the video signal processing function, when the still image is displayed along with the moving image on the display panel, the still image area is the maximum image area. It prohibits the change of the number of light emissions accompanying the switching of the number of light emissions. For example, when the maximum number of times of light emission in the moving image area has doubled, the number of light emission times per field is kept constant by multiplying the video data of the still image area by a factor of 1/2.

  As a result, for example, the luminance of the blank portion due to the difference between the screen size of the display panel and the screen size of the input video signal and the solid screen portion such as the background can be stabilized and the display quality can be improved.

  As described above, the display device of the present invention is suitably implemented in a self-luminous display panel such as a plasma display panel or an organic EL panel, and the predicting means predicts the power consumption of the display panel from the input video signal. Then, the light emission control means performs light emission control so as to suppress the power consumption to a predetermined level according to the prediction result, so that the burn-in of the panel and the power consumption of the entire display device are regulated. In a display device having a video signal processing function called so-called plasma AI that prevents the power consumption from being exceeded, a main image such as a moving image is combined with a sub-image such as a still image. In the display, the prediction means also predicts the power consumption amount in the sub-image area from the input video signal, and the light emission control means predicts the prediction result in the prediction means. In response to the power consumption amount in the sub-image area, the control of the entire panel individually controlled.

  Therefore, even if the luminance of the main image to be displayed changes, the predicted value of the power consumption in the entire panel changes, and the control state of the light emission control changes, the power consumption in the entire panel is previously determined. Since the power consumption amount in the sub-image area is controlled to a value suitable for the image in the sub-image area while being suppressed to a predetermined level, it is possible to eliminate the sub-image luminance change accompanying the main image luminance change. As a result, for example, the luminance of the blank portion due to the difference between the screen size of the display panel and the screen size of the input video signal and the solid screen portion such as the background can be stabilized and the display quality can be improved.

  Furthermore, as described above, the display control method of the present invention is preferably implemented for a plasma display panel, an organic EL panel or the like, particularly a self-luminous display panel, and each pixel of the display panel is subjected to a plurality of times within one field. To emit light, perform gradation display by the number of times of light emission, predict the power consumption of the display panel from the input video signal, and suppress the power consumption to a predetermined level or less from the prediction result. By switching the maximum number of times of light emission within one field that is applied to the entire display panel, it is possible to prevent panel burn-in and the power consumption of the entire display device from exceeding the specified rated power consumption. In a display control method for realizing a video signal processing function called so-called plasma AI, a still image is displayed on the display panel together with a moving image. Hit, the still image area prohibits change in the number of light emissions accompanying the switching of the maximum number of emissions.

  Therefore, it is possible to stabilize the luminance of the blank portion due to the difference between the screen size of the display panel and the screen size of the input video signal and the solid screen portion such as the background, thereby improving the display quality.

  FIG. 1 is a block diagram showing an electrical configuration of an image display device which is a display device according to an embodiment of the present invention. This image display apparatus generally includes three changeover switches S1, S2, and S3 corresponding to the colors R, G, and B, and three integration circuits M1, M2, M3, and a multiplication circuit K1 that individually correspond to them. , K2, K3, adder circuit 31, controller 32, delay circuit 33, three multiplier circuits K11, K12, K13, changeover switch S0, video signal-subfield correlator 34, and subfield pulse. A generation circuit 35, a scanning side driver 36, a data side driver 37, and a PDP panel 38 are provided.

  The R integration circuit M1, the G integration circuit M2, and the B integration circuit M3 respectively input R signals, G signals, and B signals through the corresponding changeover switches S1, S2, and S3 as input video signals, respectively, for a specific period. For example, a signal obtained by integrating a signal for at least one field and dividing by the number of integrated pixels is output as an R average level, a G average level, and a B average level.

  The R average level, G average level, and B average level obtained by each of the integration circuits M1, M2, and M3 are respectively input to the corresponding multiplication circuits K1, K2, and K3, and the above-described coefficients are set in advance. The result is multiplied by KR, KG, and KB, and the result is output to the adder circuit 31. Here, the coefficients KR, KG, and KB have a ratio of these coefficients equal to the ratio of the amount of power consumed for each color when an image of the same condition is displayed for each color of R, G, and B, respectively. It is set to such a value. That is, in the state where the power control by the controller 32 to be described later does not work, video signals of the same condition are sequentially input as R, G, B signals and consumed for data display when displayed in R, G, B single colors respectively. The amount of power to be measured is measured in advance, and the ratio of the measured amounts of power for each color is made equal to the ratio of the coefficients KR, KG, and KB. For example, if PR is the power consumption when a certain image is displayed in red, PG is the power consumption when the same image as that image is displayed in green, and PB is the power consumption when displayed in blue, then PR: PG: The coefficients are determined so that PB = KR: KG: KB.

  Next, the multiplication circuit K1 sets the coefficient KR to the R average level from the R integration circuit M1, the multiplication circuit K2 sets the coefficient KG to the G average level from the G integration circuit M2, and the multiplication circuit K3 sets the coefficient KB to The B average level from the B integration circuit M3 is multiplied. The adder circuit 31 adds the output signals from the integrating circuits M1, M2, and M3 to each other to obtain a predicted power consumption amount and outputs a power consumption prediction signal to the controller 32. In response to the power consumption prediction signal, the controller 32 adjusts the light emission amount (luminance) per unit area of the PDP panel 38 to select a light emission format that does not cause excessive power consumption. The light emission pulse control signal corresponding to is output. At the same time, the controller 32 calculates and outputs a multiplication coefficient so that there is no difference in the amount of light emission (brightness) of the video between the different light emission formats. Details of these operations of the controller 32 will be described later.

  On the other hand, the input video signals R, G, and B are also input to the delay circuit 33, respectively. The delay circuit 33 converts the input video signals R, G, and B into integration circuits M1 to M3 and multiplication circuits K1 to K1, respectively. Delayed video signals DR, DG, and DB delayed by the total time required for the processing of each part of K3, adder circuit 31, and controller 32 are output. The delayed video signals DR, DG, DB are input to the multiplication circuits K11, K12, K13, multiplied by the multiplication coefficient output from the controller 32, and output.

  The video signal / subfield correlator 34 receives the output signals of the multiplication circuits K11 to K13 and the light emission pulse control signal from the controller 32 and receives the output of the multiplication circuits K11 to K13 expressed as a power of two. The output signal is converted into a light emission pattern having a subfield configuration corresponding to the light emission pulse control signal, and the data of the first subfield and the second subfield of each pixel are transmitted at a predetermined timing during one field period. Data..., N-th subfield data are sent in order (n is the number of subfields). The video signal / subfield correlator 34 may perform predetermined processing such as conversion of the number of subfields to suppress the occurrence of pseudo contour.

  The subfield pulse generation circuit 35 receives the light emission pulse control signal as an input, and supplies signals such as scanning, maintenance, and erasure to the scanning side driver 36 with a light emission type subfield configuration corresponding to the light emission pulse control signal. . The scanning side driver 36 supplies signals such as scanning, maintenance, and erasing to each row electrode of the PDP panel 38 at a predetermined voltage level.

  On the other hand, the data-side driver 37 receives an output signal from the video signal / subfield associator 34, generates an image data pulse having a voltage value corresponding to each pixel data, and outputs the image data pulse for each column. And is supplied to the column electrodes of the PDP panel 38 in synchronization with the signal output from the scanning driver 36. The PDP panel 38 can actually emit light when a light emission pulse is input from the scanning side driver 36 and the light emission pulse supplied from the data side driver 37 is active. In this way, the PDP panel 38 is driven, and images corresponding to the input video signals R, G, B are displayed. In the multiplication circuits K1, K2, and K3, the average levels of the input video signals R, G, and B are multiplied by coefficients KR, KG, and KB, respectively, and then added to each other, whereby the input video signals R, It is possible to control power consumption and light emission (brightness) that are not affected by the hues of G and B.

  The above configuration is the same as that of the prior art image display device shown in FIG. 6 except that the input video signals R, G, B are passed through the changeover switches S1, S2, S3. It should be noted that in the present invention, the side panels can be displayed by the change-over switches S1, S2, and S3, and correspondingly, the multiplication circuits K11 to K13 are set. That is, the multiplication coefficient is switched between the multiplication coefficient of the video section and the multiplication coefficient of the side panel section by the changeover switch S0.

  Specifically, video signals R, G, and B of the video section and video signals Rsp, Gsp, and Bsp of the side panel section are input to the image display device from a television receiver circuit (not shown). Similarly, in response to a video / side panel switching signal input from the outside, the change-over switches S1, S2, S3 are switched, and the video signals R, G, B and video signals Rsp, Gsp and Bsp are selectively input to the integration circuits M1, M2, and M3. On the other hand, the adder circuit 31 integrates at least one field of the video signals R, G, B; Rsp, Gsp, Bsp of the entire screen of the video unit and the side panel unit, and per unit area of the PDP panel 38. Is predicted as the total area power consumption, and the still image area power consumption is predicted only from the video signals Rsp, Gsp, and Bsp of the side panel unit.

  Similarly to the conventional technique, the controller 32 selects a light emission format (light emission time and the number of times of light emission) from the predicted power consumption of the entire area of the power consumption prediction signal from the adder circuit 31, and outputs a light emission pulse control signal. At the same time, the video unit multiplication coefficient is set based on the predicted power consumption of the entire area and output. Further, in the present invention, the controller 32 sets and outputs a side panel unit multiplication coefficient based on the still image area power consumption prediction value. These multiplication coefficients are switched by the changeover switch S0 in response to the video part / side panel part switching signal, and are selectively set in the multiplication circuits K11 to K13.

  Therefore, also in this image display device, as in the conventional image display device, the controller 32 changes the input video signals R, G, B, for example, the amount of information to be displayed is large, and the power consumption is large. In this case, the light emission amount / brightness of the PDP panel 38 is suppressed so as to limit the power consumption within a certain range. That is, the light emission format (light emission time and the number of times of light emission) and the gradation of the display image are controlled so that the amount of power consumption during image display does not exceed a certain reference value P. Specifically, the controller 32 changes the light emission format from, for example, A to D in accordance with the overall power consumption prediction value of the power consumption prediction signal, and a light emission pulse control signal for controlling the light emission format D; Video portion multiplication coefficients for adjusting the gradation levels of the delayed video signals DR, DG, and DB are output so that the light emission amount and luminance in the PDP panel 38 smoothly transition between the different light emission formats A and D. In addition, in the present invention, the controller 32 also outputs a side panel unit multiplication coefficient according to the power consumption amount of the still image area of the power consumption prediction signal, and the ratio of the number of times of light emission between the light emission format A and the light emission format D. The side panel multiplication coefficient is set to 5/2 (calculated from FIG. 7).

Therefore, as shown in FIG. 2, as in FIG. 10, an example in which a video signal having an aspect ratio of 4: 3 is input to a display panel having an aspect ratio of 16: 9 will be described. When the gradation level of the input video signals Rsp, Gsp, and Bsp is 10, and the gradation level of the peak pixel in the input video signals R, G, and B in the moving image area 1 is 100, it is shown in FIG. Thus, when the picture in the moving image area 1 is generally dark and the light emission format determined based on the predicted value of the entire area power consumption is A, the total light emission number (maximum light emission number) is five times 500 times. The peak luminance at this time is, for example, 500 cd / m ² . In the side frame 2 portion, the number of times of light emission is 50, and the luminance is 50 cd / m ² . The display in the light emission format A in FIG. 2A is the same as that in FIG.

On the other hand, as shown in FIG. 2B, when the pattern in the moving image area 1 becomes generally brighter and the light emission format determined based on the predicted value of the entire area power consumption becomes D, the total light emission The number of times is doubled to 200 times, and the peak luminance is 200 cd / m ² . However, since the video signals Rsp, Gsp, and Bsp of the side frame 2 portion are multiplied by 5/2 which is a multiplication coefficient, the number of times of light emission of the side frame 2 portion remains 50 times, and thus the luminance is 50 cd. / M ² remains. As described above, even if the levels of the input video signals R, G, and B in the moving image area 1 change and the light emission format is switched, the video signals Rsp, Gsp, and Bsp in the side frame 2 portion do not change. The luminance of the side frame 2 portion is kept constant without following it.

  Hereinafter, a method of determining the light emission format and the multiplication coefficient in the controller 32 will be described. First, the light emission format will be described. In the present image display device, the total number of times of light emission (maximum number of times of light emission) allowed in one frame period is 1275 as the value of the power consumption prediction signal increases as shown in FIG. There are five light emission formats A, B, C, D, and E, which are as small as 1020, 765, 510, and 255.

  On the other hand, the input video signals R, G, B; Rsp, Gsp, Bsp can be expressed by gradation levels of 8-bit gradation from 0 to 255, and the light emission format E is equal to the gradation level (1). The light emission format A is 5 times the gradation level, the light emission format B is 4 times the gradation level, and similarly, the light emission format C and the light emission format D are each 3 times the gradation level. The number of light emission pulses is set so that light is emitted twice as many times. These light emission formats A to E are switched based on the power consumption prediction signal. The relationship of the light emission formats A to E with respect to the predicted power consumption amount is shown in FIGS. 3 (a), 4 (a), and 5 (a).

  Here, in correspondence with FIG. 9, FIG. 3 is a graph showing the change of each parameter with respect to the predicted value of the entire area power consumption by the moving image area 1, and FIG. 4 is the entire area consumption by the side frame 2 portion. FIG. 5 is a graph showing the change of each parameter with respect to the total power consumption by the entire area of the PDP panel 38 combining FIG. 3 and FIG. 4. 3 (b), 4 (b) and 5 (b) correspond to FIG. 9 (b), and show the change of the multiplication coefficient in each of the light emission formats A to E. FIG. 4 (c) and FIG. 5 (c) correspond to FIG. 9 (c) described above, and show changes in luminance in the respective light emission formats A to E. FIG. 3 (d) and FIG. FIG. 5 (d) and FIG. 5 (d) correspond to FIG. 9 (b) described above, and show changes in the power consumption in each of the light emission formats A to E.

  Although the amount of change in power consumption is 0 to 1, the change point is the same as TB, TC, TD, TE in FIG. 9, and TB ′, TC ′, TD ′ in FIGS. , TE ′, but may be equal to each other. Since the light emission formats A to E are applied to the entire area of the PDP panel 38, FIGS. 3A, 4A, and 5A are equal to each other.

  However, the multiplication coefficient of the side frame 2 portion shown in FIG. 4 (b) is 5C / 4 for the light emission format B, and 5C / 4 for the light emission format C, where the number of times of light emission of the light emission format A is a reference value, for example It is set according to the ratio of the number of times of light emission, such as 5C / 3, 5C / 2 for the light emission format D, and 5C for the light emission format E. Therefore, as described above, the luminance of the side frame 2 portion is changed even if the predicted value of the total power consumption obtained from the input video signals R, G, B changes as shown in FIG. As long as the predicted value of the power consumption of the still image area obtained from the input video signals Rsp, Gsp, Bsp does not change, it is a constant value of Ysp. Therefore, the power consumption of the side frame 2 shown in FIG. 4D is also a constant value of Psp.

  On the other hand, the multiplication coefficient of the moving image area 1 portion shown in FIG. 3B is set to the light emission formats A, B, C, and D at the switching points TB ′, TC ′, TD ′, and TE ′. In the light emission format A, the values are obtained as described with reference to FIG. 8 and are 0.8, 0.75, 0.67, and 0.5, respectively, as in FIG. 9B. On the low power consumption side, coefficient 1 is set at a point T0 of a certain amount of power consumption value, and there is no setting of this multiplication coefficient on the low power consumption side. As described above, the side frame 2 portion is driven at a low gradation level, and even if the moving image area 1 portion is a black screen with a gradation level 0, the power of T0 is applied to the PDP panel 38. This is because consumption occurs.

  Then, the luminance of the moving image area 1 portion shown in FIG. 3C becomes lower as the predicted value of the whole area power consumption becomes lower with the point T0 as the maximum luminance. As a result, the power consumption of the moving image area 1 is generated after the predicted value of the entire area power consumption exceeds T0 as shown in FIG. The value obtained by subtracting the power consumption Psp of the two portions is suppressed so as not to greatly exceed. Therefore, as shown in FIG. 5D, the power consumption of the entire area of the PDP panel 38 starts with the power consumption Psp of the side frame 2 portion as the starting point with respect to the increase of the predicted power consumption of the entire area. When the point T0 is exceeded, it increases and is suppressed so as not to greatly exceed the reference value P.

  As described above, the image display device according to the present invention is suitably implemented in a self-luminous display panel such as a plasma display panel or an organic EL panel, and causes each pixel of the PDP panel 38 to emit light a plurality of times within one field. Further, gradation display is performed by the number of times of light emission, and the power consumption per unit area of the PDP panel 38 is predicted from the input video signals R, G, B, and the entire PDP panel 38 is estimated from the predicted power consumption amount. By setting the light emission format applied to the PDP panel 38, the power consumption of the PDP panel 38 is suppressed to the vicinity of a predetermined reference value P, and the burn-in of the panel and the power consumption of the entire image display device are regulated. In an image display device having a video signal processing function called a so-called plasma AI, which prevents the power from being exceeded, a moving image When the sub-image such as a still image is displayed together with the main image of the image, the average value of the power consumption of the entire panel obtained as described above is set as the total power consumption amount, and the input of the side frame 2 portion which is the still image region is input. From the video signals Rsp, Gsp, Bsp, the power consumption per unit area is predicted as the still image area power consumption, and the total light emission of the light emission format suitable for the prediction result and the light emission format applied to the entire panel The coefficient corresponding to the ratio of the number of times is multiplied by the delay signal of the input video signals Rsp, Gsp, and Bsp of the side frame 2 portion, so that the luminance of the moving image area 1 changes, the light emission format changes, and the total light emission Even if the number of times changes, the number of times of light emission of the side frame 2 portion is kept constant, and the luminance change of the sub-image accompanying the luminance change of the main image can be eliminated. As a result, a margin due to the difference between the screen size (aspect ratio) of the display panel and the screen size of the input video signal (for example, a 4: 3 screen size is added to a 16: 9 screen size display panel as shown in FIG. 2). The side frame 2 when the signal is input, the upper and lower frame portions when the signal with the screen size of 16: 9 is input to the display panel with the screen size of 4: 3 as shown in FIG. In addition, the brightness of the solid screen portion such as the background can be stabilized and the display quality can be improved.

  Furthermore, the input video signal is a full-color signal composed of R, G, and B color components, and the PDP panel 38 displays the same image in a single color for each of the R, G, and B colors. Further, the ratio of power consumed for each display is KR: KG: KB, and the input video signals R, G, and B for at least one field are respectively integrated to obtain the R average level, G average level, B An R integration circuit M1, a G integration circuit M2, and a B integration circuit M3 that output each of the average levels, and a multiplication circuit K1 that multiplies the R average level, the G average level, and the B average level by the ratios KR, KG, and KB, respectively. , K2, K3, and a controller 32 for obtaining the total area power consumption and still image area power consumption from the sum of the outputs of the multiplication circuits K1, K2, K3. After weighting, the light emission amount (brightness) and power consumption are controlled based on the total area power consumption and still image area power consumption obtained by taking the sum, and the hue of the input video signals R, G, B It is possible to control the power consumption and the amount of light emission (luminance) that are not affected by.

  In the above example, the multiplication coefficients KR, KG, and KB are obtained from the power ratio when the same image is displayed in a single color with each color of R, G, and B. Based on the area ratio WR: WG: WB of the phosphor, it may be determined more simply. That is, when the ratios WR: WG: WB of the discharge areas of the respective colors R, G, B are equal to each other, the electric power PR, PG, consumed for data display when each single color is displayed on the panel. The ratios of PB are approximately equal, and the multiplication coefficients may be equal to each other. On the other hand, when the areas of the respective color phosphors are formed unevenly for the purpose of improving the color temperature or the like, the area ratio is approximately the ratio of power consumption, so the multiplication coefficients KR, KG, and KB. May be set according to the area ratio.

  In the above example, the input video signals R, G, and B are the signals of the moving image area 1, the input video signals Rsp, Gsp, and Bsp are the signals of the side frame 2 part, and these are the changeover switches S1, S2, S3. However, this is because a signal source for separately generating the signal (data) of the side frame 2 portion is provided. In the video signal source, one horizontal signal is generated. When processing such as inserting data of the side frame 2 portion at the beginning and end of the period and inserting a signal of the moving image area 1 at the center of the one horizontal period is possible, such a signal is input to the input video signal R. , G, B may be directly input to the integrating circuits M1, M2, M3, and the changeover switches S1, S2, S3 may be omitted. Furthermore, when the video part / side panel part switching signal is input to the controller 32 and the controller 32 can switch and output the multiplication coefficient, the switch S0 may be omitted.

  The present invention is preferably applied to a self-luminous display panel such as a plasma display panel or an organic EL panel. Each pixel of the PDP panel 38 emits light a plurality of times within one field, and gradation display is performed by the number of times of light emission. In addition, the power consumption per unit area of the PDP panel 38 is predicted from the input video signals R, G, B, and the light emission format applied to the entire PDP panel 38 is set from the predicted power consumption. As a result, the power consumption of the PDP panel 38 is suppressed to the vicinity of a predetermined reference value P, and the image burn-in of the panel or the power consumption of the entire image display device exceeds the specified rated power consumption. In an image display device having a video signal processing function called so-called plasma AI, which is prevented, a still image is displayed together with a moving image. What for switching of the light emitting format by the luminance change of the moving image, it is possible to suppress the luminance change of the still image.

1 is a block diagram illustrating an electrical configuration of an image display apparatus according to an embodiment of the present invention. It is a figure which shows the change of the display screen of this invention by the change of an input video signal, when a side frame is provided in the both sides of a moving image area | region for the difference in an aspect ratio. It is a graph which shows the change of each parameter with respect to the predicted value of the whole area power consumption in a moving image area. It is a graph which shows the change of each parameter with respect to the predicted value of the said whole area power consumption in a side frame part. FIG. 5 is a graph showing changes in parameters with respect to overall power consumption in the entire area of the PDP panel in which FIGS. 3 and 4 are combined. It is a block diagram which shows the electric constitution of the image display apparatus of a prior art. It is a figure which shows the frequency | count of light emission in each light emission format set by multiple types, and allocation of a subfield. It is a figure for demonstrating the determination method of the switching point of a light emission format. It is a graph which shows the change of each parameter with respect to the power consumption predicted value of the conventional PDP panel. It is a figure which shows the change of the display screen of a prior art by the change of an input video signal, when providing a side frame in the both sides of a moving image area. It is a figure which shows the other example which displays a still image together with a moving image.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Moving image area 2 Side frame 31 Adder circuit (prediction means)
32 controller (light emission control means)
33 Delay circuit 34 Video signal-subfield correlator 35 Subfield pulse generation circuit 36 Scanning side driver 37 Data side driver 38 PDP panel (display panel)
K1, K2, K3 multiplication circuit (prediction means)
K11, K12, K13 Multiplication circuit (light emission control means)
M1, M2, M3 integration circuit (prediction means)
S0 selector switch (light emission control means)
S1, S2, S3 selector switch (prediction means)

Claims (5)

In a display device that performs light emission control so that the prediction means predicts the power consumption of the display panel from the input video signal, and the light emission control means suppresses the power consumption to a predetermined level according to the prediction result. When displaying a sub-image together with a main image,
The prediction means also predicts power consumption in the sub-image area from the input video signal,
The display device according to claim 1, wherein the light emission control unit individually controls the power consumption in the sub-image area in response to a prediction result of the prediction unit. The light emission control means causes each pixel of the display panel to emit light a plurality of times within one field, performs gradation display by the number of times of light emission, and the prediction means for the power consumption of the entire display panel by a plurality of types is predicted. The maximum number of times of light emission within the one field applied to the entire display panel is set to the number set for each power consumption range depending on which of the set power consumption ranges corresponds. Thus, while suppressing the power consumption of the display panel to the predetermined level, the input video signal of the sub-image area, the range to which the predicted power consumption amount of the sub-image area by the prediction unit belongs, Obtain a coefficient according to the ratio of the maximum number of times of light emission with the range to which the predicted power consumption of the entire display panel belongs,
The display device according to claim 1, further comprising a multiplying unit that multiplies the input video signal in the sub-image area by the coefficient. The light emission control unit divides one field of the input video signal into a plurality of weighted subfields, and displays the gradation display by temporally overlapping and displaying the video of each subfield, and the maximum light emission The number of times is determined for each light emission format set according to which of the power consumption ranges in which the predicted value of the power consumption amount is set, and the light emission control means represents the set light emission format. Output light emission control signal,
Video signal-subfield association means for associating an input video signal with a subfield configuration of a light emission format corresponding to the light emission pulse control signal;
3. The display device according to claim 2, further comprising subfield pulse generating means for generating a light emission pulse in a light emission type subfield configuration based on the light emission pulse control signal in response to the light emission pulse control signal. The input video signal is a full-color signal composed of R, G, and B color components, and the display panel displays each of the R, G, and B colors when the same image is displayed in a single color. The ratio of power consumed for display and / or the area ratio of phosphors is KR: KG: KB;
The prediction means includes
An R integration circuit, a G integration circuit, and a B integration circuit, each of which integrates at least one field of input video signals R, G, and B and outputs each of the R average level, the G average level, and the B average level;
First to third multiplication circuits for multiplying the R average level, G average level, and B average level by the ratios KR, KG, and KB, respectively;
A power consumption prediction circuit that obtains the power consumption of the entire display panel and the power consumption of the sub-image area from the sum of the outputs of the first to third multiplication circuits,
When the input video signals R, G, and B are signals in the main image area, the multiplying unit multiplies the predetermined ratios KR, KG, and KB, respectively, to obtain signals in the sub-image area. Consists of fourth to sixth multiplication circuits that respectively multiply the coefficients obtained by the light emission control means,
4. The video signal-subfield associating means associates outputs from the fourth to sixth multiplier circuits with a subfield configuration of a light emission format corresponding to a light emission pulse control signal. Display device. Each pixel of the display panel is caused to emit light a plurality of times within one field, and gradation display is performed by the number of times of light emission, and the power consumption per unit area of the display panel is predicted from the input video signal. In the display control method of switching the maximum number of times of light emission in the one field applied to the entire display panel so as to suppress the power consumption per unit area to a predetermined level or less,
A display control method characterized in that, when a still image is displayed together with a moving image, the still image area prohibits a change in the number of times of light emission accompanying switching of the maximum number of times of light emission.

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