JPH11109912A - Display device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent a display device from being suddenly changed in brightness at the connection part of display panels. SOLUTION: This display device is provided with two (n=2) display panels 101 , 102 forming one screen and a driving circuit 141 , 142 for individually driving the display panels 101 , 102 ; the device outputs to the driving circuit a control constant CP for suppressing power consumption, setting it for the display panel 101 , 102 at less than a normal value. In this case, the device is provided with a control circuit 20 which determines an average video level for the display panel 101 , 102 on the basis of an input video signal V1 , V2 and which outputs to the driving circuit 141 , 142 a control constant CPM(CP for example) corresponding to the display panel (102 for example) with the maximum average video level; such display panel with the maximum average video level is also maximum in its power consumption; therefore, by outputting the control constant CPM to the driving circuit 141 , 142 , the driving circuit 141 , 142 can be kept in the driving state with the same control constant CPM even if the display panel 101 , 102 are different from each other in power consumption.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention
Is an integer of 2 or more), and outputs a control constant CP for suppressing power consumption to n driving circuits for individually driving each display panel, so that the power consumption of each display panel is equal to or less than a specified value. (For example, a large-screen display device). The control constant CP is not limited to this, but represents, for example, a constant that increases the power consumption suppressing power as its value increases.

[0002]

2. Description of the Related Art Conventionally, this type of display device has been configured as shown in FIG. That is, two screens (n =
2) display panels 10 ₁ and 10 ₂ , and the display video extraction / conversion units 12 ₁ and 12 ₂ extract the video signals for the display panels 10 ₁ and 10 ₂ from the input video signal and enlarge them on each screen. Are converted into the display video signals V1 and V2, and the driving circuits 14 ₁ ,
14 ₂ displays an image by outputting a driving signal to the display panel 10 _1, 10 ₂ on the basis of the display video signal V1, V2. The power consumption detectors 16 ₁ and 16 ₂ are driven by the drive circuits 14 ₁ and 1
4 power consumption ₂ detects (indirectly display panel 10 _1, 1
0 ₂ ), and based on the detected values K 1 and K ₂ , the corresponding control constants CP from the control circuits 18 ₁ and 18 _2.
1 and CP2 are output to the driving circuits 14 ₁ and 14 _2, and the power consumption of the display panels 10 ₁ and 10 ₂ is controlled to be equal to or less than a specified value. The display panels 10 ₁ and 10 ₂ are PDP (plasma display panel) or LCD (liquid crystal display)
It is composed of panels and the like.
The number of sustain pulses in a frame is reduced, and the number of discharges per frame is reduced to reduce power consumption.
In FIG. 9, reference numeral 11 denotes a panel block assembly obtained by joining two panel blocks.

[0003]

[SUMMARY OF THE INVENTION However, in the conventional example shown in FIG. 9, the power consumption of the display panel 10 _1, 10 ₂ are different, also the emission luminance differs with the same input level, such as sunrise and sunset When a wide range of gradation (brightness gradient) is displayed, the display panel 10 ₁ ,
There is a problem that may become brighter or become suddenly dark 10 ₂ of the seam.

For example, consider a case where the luminance level of an input video signal increases linearly from the left end to the right end of the screen as shown by a dotted line Y1 in FIG. Since the display panels 10 ₁ and 10 ₂ have the characteristic of increasing power consumption when displayed brightly, the power consumption of the right display panel 10 ₂ is higher than that of the left display panel 10 _{1 in FIG} . Therefore, the control circuit 182 _{sends the} drive circuit 1
4 control constant and outputs the ₂ CP2 (e.g. 8) of the control constants CP1 output from the control circuit 18 ₁ to the drive circuit 14 ₁
(For example, 2), and the display panel 1
As shown by the solid line Y2 in FIG. 10, there is a problem that the brightness level of the image displayed at 0 ₁ and 10 ₂ suddenly becomes dark at the joint M of the display panels 10 ₁ and 10 ₂ . Further, when the luminance level of the input video signal decreases linearly from the left end to the right end of the screen, on the contrary, the brightness suddenly increases at the joint M of the display panels 10 ₁ and 10 _2. was there.

SUMMARY OF THE INVENTION The present invention has been made in view of the above-mentioned problems. One screen is formed by n display panels, and power consumption is reduced in each of n drive circuits for individually driving each display panel. It is an object of the present invention to prevent a sudden change in brightness at a joint of display panels in a display device that outputs a control constant CP for use in a display device so that power consumption of each display panel is equal to or less than a specified value. It is another object of the present invention to prevent the brightness of each display panel from changing suddenly or frequently as needed.

[0006]

According to a first aspect of the present invention, there are provided n display panels forming one screen, and n drive circuits for individually driving each display panel based on an input video signal. Then, a control constant C for suppressing power consumption is provided in the n drive circuits.
In a display device that outputs P to reduce the power consumption of each display panel to a specified value or less, the average image level of each display panel is obtained based on the input video signal, and the maximum average image level corresponds to the display panel. And a control circuit for outputting the control constant CPM to the n drive circuits.

[0007] The control circuit obtains an image average level of each display panel based on the input image signal, and a control constant CPM (for example, CP) corresponding to the display panel having the maximum image average level.
2) is output to n drive circuits. Since the power consumption of the display panel (for example, the display panel 10 ₂ ) having the maximum image average level is the highest, the corresponding control constant CPM is output to the n drive circuits, so that the power consumption of each display panel is reduced. Even if the power consumption becomes equal to or less than the specified value and the power consumption of the n display panels is different, the n drive circuits can be driven to the same control constant CPM. For this reason, it is possible to prevent a sudden change in brightness at a joint (border) of the display panel as in the conventional example.

According to a second aspect of the present invention, in the first aspect of the present invention, there are provided n power consumption detecting circuits for individually detecting the power consumption of each display panel, and the control circuit controls each of the display panels based on an input video signal. A video average level of the display panel is obtained, and a control constant CPM of a detection value corresponding to the display panel having the maximum video average level among the detection values of the n power consumption detection circuits.
(For example, CP2) is output to all of the n drive circuits as a common control constant. For this reason, the power consumption of each display panel becomes equal to or less than the specified value, and even if the power consumptions of the n display panels are different, the n drive circuits have the same control constant C.
The PM can be driven.

According to a third aspect of the present invention, in order to simplify the configuration of the control circuit, the control circuit includes a video signal level detecting section, n average level extracting sections, a comparator and a control constant. And a maximum value output by comparing the obtained video average levels with a comparator and outputting the maximum value by a control constant generation unit. Control constant CP of the detected value corresponding to the output signal of the comparator among the detected values of the power consumption detecting circuit
M is generated and output to all of the n drive circuits as a common control constant.

According to a fourth aspect of the present invention, in the first aspect of the present invention, the control circuit determines an image average level of each display panel based on an input image signal, and controls a control constant corresponding to the display panel having the maximum image average level. The power consumption of each display panel is equal to or less than a specified value by forming the CPM with n control circuits that output the corresponding drive circuits and outputting the same control constant CPM from the n control circuits to the corresponding drive circuits. In addition, even if the power consumption of the n display panels is different, the n drive circuits can be driven in the same control constant CPM.

According to a fifth aspect of the present invention, in order to simplify the configuration of the n control circuits, each of the control circuits includes a video signal level detecting section, n average level extracting sections, And a control constant generation unit. The average image level of each panel is obtained by n average level extraction units, the obtained image average levels are compared by a comparator, and the maximum value is output. , Generates a control constant CPM based on the output signal of the comparator, and outputs it to the corresponding drive circuit.

According to a sixth aspect of the present invention, in the first aspect of the present invention, there are provided n power consumption detecting circuits for individually detecting the power consumption of each display panel, and a control circuit is provided for detecting each power consumption detecting circuit. A first control circuit that outputs a corresponding control constant based on the value, the output control constant varies with a control signal input to a brightness adjustment terminal, and a video average of each display panel based on an input video signal. And a second control circuit for outputting a control signal corresponding to a difference between the maximum value of the image average level and the image average level of the target display panel to the luminance adjustment terminal of the first control circuit. , The display panel having the maximum video average level (for example, the display panel 10
₂ ) Control constant CP for keeping power consumption below specified value
M is output to n drive circuits, and the power consumption of each display panel is reduced to a specified value or less. Even if the power consumption of the n display panels is different, the n drive circuits have the same control constant CPM.
Can be driven.

According to a seventh aspect of the present invention, in order to simplify the configuration of the second control circuit, each of the n second control circuits is provided with a video signal level detector and an n number of averages. It comprises a level extractor, a comparator, and a control signal generator. The n average level extractors determine the image average level of each panel, and the comparator compares the image average levels determined by each average level extractor. Outputting a difference signal between the maximum value of the image average level and the image average level of the target display panel, and the control signal generation unit generates a control signal corresponding to the difference signal and outputs the control signal to the luminance adjustment terminal of the first control circuit. Thus, the first control circuit outputs a control constant CPM corresponding to the display panel having the maximum image average level to the drive circuit.

According to an eighth aspect of the present invention, in order to further simplify the configuration of the second control circuit in the sixth aspect of the present invention,
Each of the control circuits includes a video signal level detection unit, a maximum level extraction unit, and a control signal generation unit, and the maximum level extraction unit obtains the maximum value among the video average levels of each panel, and the control signal generation unit Generates a control signal based on the maximum video average level and the output control constant of the first control circuit, and outputs the control signal to the brightness adjustment terminal of the first control circuit. The control constant CPM corresponding to the display panel is output to the drive circuit.

According to a ninth aspect of the present invention, there are provided n display panels for forming one screen, and n drive circuits for individually driving each display panel based on an input video signal. In a display device in which a control constant CP for suppressing power consumption is output to a circuit so that power consumption of each display panel is equal to or less than a specified value, a video average level of each display panel is obtained based on an input video signal, The control constant CPM corresponding to the display panel having the maximum average level is obtained, and the control constant C
It is characterized by including a control circuit that creates a control constant CPMa having a larger power consumption suppressing power than PM and outputs the control constant CPMa to n drive circuits.

Each of the n control circuits calculates an image average level of each display panel based on an input image signal, and a control constant CPM corresponding to the display panel having the maximum image average level (maximum power consumption). (For example, CP2) to the corresponding drive circuit. Since the control constant CPMa having a larger power consumption suppressing power than the control constant CPM is output to the corresponding drive circuit, the power consumption of each display panel becomes equal to or less than a specified value, and the power consumption of the n display panels differs. Even so, the n driving circuits can be driven with the same control constant CPMa. For this reason, it is possible to prevent a sudden change in brightness at the seam of the display panel.

According to a tenth aspect of the present invention, in the ninth aspect of the present invention, there are provided n power consumption detecting circuits for individually detecting the power consumption of each display panel, and the control circuit controls each of the display panels based on an input video signal. An image average level of the display panel is obtained, and a control constant CPM of a detection value corresponding to the display panel having the largest image average level among the detection values of the n power consumption detection circuits is obtained, and the power consumption is calculated from the control constant CPM. A control constant CPMa having a large suppressing force is created, and this control constant CP
It is configured to output Ma as a common control constant to n drive circuits. Since the control constant CPMa having a larger power consumption suppressing power than the control constant CPM of the power consumption detection value for the display panel having the largest image average level is output to all of the n drive circuits, the power consumption of each display panel is specified. Even if the power consumption is equal to or less than the value and the power consumption of the n display panels is different, the n drive circuits can be driven to the same control constant CPMa.

In the eleventh aspect of the present invention, n screens are formed.
Display panels, and n drive circuits for individually driving each display panel based on an input video signal, and outputting a control constant CP for suppressing power consumption to the n drive circuits to display each display panel. In a display device in which power consumption of the panel is equal to or less than a specified value, an image average level of each display panel is obtained based on an input image signal, and a control constant CPM corresponding to the display panel having the maximum image average level is obtained. Initially, control constants CP1 and C corresponding to the average image level of each display panel
, CPn are output to each of the corresponding drive circuits, and a common control constant CPM is generated with the passage of time.
And n control circuits for outputting a control constant approaching to the control circuit to each of the corresponding drive circuits.

Each of the n control circuits obtains an image average level of each display panel based on the input image signal, and obtains a control constant CPM corresponding to the maximum image average level.
First, control constants CP1, CP2,..., CPn corresponding to the image average level of each display panel are output to each of the corresponding drive circuits, and the control constants approach the common control constant CPM over time. For this reason, the power consumption of each display panel can be reduced to a specified value or less, the n driving circuits can be driven with the same control constant CPM over time, and the brightness of the display panel changes rapidly or frequently. Can be prevented.

According to a twelfth aspect of the present invention, n screens are formed.
Display panels, and n drive circuits for individually driving each display panel based on an input video signal, and outputting a control constant CP for suppressing power consumption to the n drive circuits to display each display panel. In a display device in which power consumption of the panel is equal to or less than a specified value, an image average level of each display panel is obtained based on an input image signal, and a control constant CPM corresponding to the display panel having the maximum image average level is obtained. A control constant CPMa having a larger power consumption suppressing power than the control constant CPM is created, and first, control constants CP1, CP2,..., CPn corresponding to the average image level of each display panel are output to the corresponding drive circuits. And n control circuits for outputting control constants approaching the common control constant CPMa to the corresponding drive circuits over time. And butterflies.

Each of the n control circuits initially includes control constants CP1 and CP1 corresponding to the average image level of each display panel.
CPn are output to each of the corresponding driving circuits, and the control constant approaches a common control constant CPMa with the passage of time. For this reason, the power consumption of each display panel can be reduced to a specified value or less, the n driving circuits can be driven with the same control constant CPMa over time, and the brightness of the display panel changes rapidly or frequently. Can be prevented.

[0022]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 shows an embodiment (corresponding to claims 1, 2 and 3) of a display device according to the present invention.
The same parts as those in FIG. 9 are denoted by the same reference numerals. In FIG. 1, 10
_1, 10 ₂ in the display panel which is constituted by a PDP or an LCD panel, these display panels 10 _1, 10 ₂ in the entire
Forming the screen. 14 ₁ and 14 ₂ are drive circuits, and each drive circuit 14 ₁ and 14 ₂ is a corresponding display panel 10 ₁ , 1
In order to display an enlarged image at 0 ₂ , a drive signal is output to the display panels 10 ₁ and 10 ₂ based on the display image signals V 1 and V ₂ extracted and converted from the input image signal, and a predetermined image (for example, It is configured to display one screen image such as sunrise or sunset.

Reference numerals 16 ₁ and 16 ₂ denote power consumption detection circuits. Each of the power consumption detection circuits 16 ₁ and 16 ₂ includes the driving circuit 14 ₁ ,
14 ₂ power consumption is detected (indirectly, the display panel 10 ₁ ,
10 ₂ power consumption), and the detected values K1, K2
Is configured to be output. 20 is a control circuit,
As shown in FIG. 2, the control circuit 20 includes video signal level detectors 22 ₁ , 22 ₂ , average level extractors 24 ₁ , 2
4 ₂ , a comparator 26 and a control constant generator 28.

The video signal level detectors 22 ₁ , 22
₂ detects video levels (eg, luminance levels) of video signals V1 and V2 for displaying video on the corresponding display panels 10 ₁ and 10 ₂ , and detects the average level extracting sections 24 ₁ and 24 _2.
Are based on the detected video level, the display panel 10 ₁ ,
Extract 10 ₂ video average levels VML1 and VML2,
The comparator 26 has the image average levels VML1 and VML2.
And outputs the maximum value (for example, VML2), and the control constant generation unit 28 outputs the power consumption detection circuits 16 ₁ , 1
6 ₂ to output a control constant of the detected value corresponding to the maximum value outputted from the comparator 26 of the detection value K1, K2 (e.g. VML2) (e.g. K2) (e.g. CP2) by, is constituted respectively I have.

The control constant generation unit 28, for example, detects in advance the detection values K1 and K1 of the power consumption detection circuits 16 ₁ and 16 ₂ .
A read only memory (ROM) storing K2 as an address and storing control constants CP1 and CP2 as data;
Based on the maximum video average level VML2 output from the comparator 26, the data (C) of the corresponding address (detection value K2)
P2).

Next, the operation of FIGS. 1 and 2 will be described with reference to FIG. For convenience of explanation, the input video signals V1, V2
Is assumed to increase linearly from the left end to the right end of the screen, as shown by the dotted line Y1 in FIG. Since the display panels 10 ₁ and 10 ₂ have the characteristic of increasing power consumption when displayed brightly, the right display panel 10 ₂ consumes more power than the left display panel 10 ₁ , and the power consumption detection circuit 16 ₁ , the detection value K from 16 ₂
1 and K2 are output, and the detected values K1 and K2 correspond to the control constants CP1 (for example, 2) and CP2 (for example, 8) as in the case of FIG.

In the control circuit 20, the video signal level detectors 22 ₁ and 22 ₂ detect the video levels of the video signals V1 and V2, and the average level extractors 24 ₁ and 24 ₂ display the display panel 1
The video average levels VML1 and VML2 of 0 ₁ and 10 ₂ are extracted, the comparator 26 compares the video average levels VML1 and VML2 and outputs the maximum value VML2, and the control constant generation unit 28
Outputs the control constant CP2 (for example, 8) of the detection value K2 corresponding to the maximum value VML2 of the detection values K1 and K2 to the drive circuits 14 ₁ and 14 ₂ as a common control constant, and outputs the display panel 10 ₁ , 10 power consumption ₂ is controlled to be below the specified value.

As described above, the drive circuit 14 ₁ ,
14 ₂ , the display panels 10 ₁ , 10 ₂
Even if the power consumption of the differences can be a drive circuit 14 _1, 14 ₂ to drive the state of the same control constant CP2. For this reason, the luminance of the display panels 10 ₁ and 10 ₂ linearly increases from the left end to the right end of the screen as shown by the solid line Y3 in FIG. ₁ , 10 ₂
Abrupt change in brightness can be prevented at the seam M.

In the embodiment shown in FIG. 1, the control circuit 2
0 is composed of a video signal level detection unit, two average level extraction units, a comparator and a control constant generation unit as shown in FIG. 2, so that the circuit configuration is simplified. The video average levels VML1 and VML2 of the display panels 10 ₁ and 10 ₂ are obtained based on the input video signal, and the detection values K ₁ and K ₂ of the power consumption detection circuits 16 ₁ and 16 _{2 are} calculated.
The maximum control constant CP2 detection value K2 corresponding to the display panel 10 _second video average level VML2 of one of K2, as long as it outputs to all the drive circuits 14 _1, 14 ₂ as a common control constants.

For example, the two average level extractors 24 and 24 and the comparator 26 of the control circuit 20 shown in FIG. 2 are constituted by one maximum average level extractor, and the maximum average level extractor outputs a video signal level. If the larger one of the image average levels VML1 and VML2 of the display panels 10 ₁ and 10 ₂ (which is also the maximum value) is obtained and output based on the detection values of the detectors 22 ₁ and 22 ₂ , the circuit The configuration can be further simplified.

In the embodiment shown in FIG. 1, power consumption detecting circuits 16 ₁ and 16 ₂ are provided, and a video signal input to the control circuit 20 is converted to a display video signal V for the display panels 10 ₁ and 10 ₂ .
1, has been described using the present invention to V2 and the display device, the present invention is not limited thereto, omitting the power detection circuit, a display panel 10 ₁ a video signal to be input to the control circuit, the display device with a video signal constituting the one screen at 10 ₂ may also be utilized. 4 and 5 show an embodiment (corresponding to claims 1, 4 and 5) in such a case, and the same parts as those in FIGS. 1 and 2 are denoted by the same reference numerals.

In FIG. 4, reference numerals 30 ₁ and 30 ₂ denote control circuits provided corresponding to the display panels 10 ₁ and 10 _2. The control circuit 30 ₁ (30 ₂ ) has a display circuit as shown in FIG. Video extraction / conversion unit 32 ₁ (32 ₂ ), video signal level detection unit 3
4 ₁ (34 ₂ ), average level extraction units 36 ₁ , 38 ₁ (3
6 _2, 38 _2), and a comparator 40 ₁ (40 ₂₎ and the control constant generation unit 42 ₁ (42 _2).

The display video extraction / conversion unit 32 ₁ extracts a video signal for the display panel 10 ₁ from an input video signal,
It is configured to convert to an enlarged video signal and output it as a display video signal V1. The display video extraction / conversion unit 3
2 ₂ extracts a video signal for the display panel 10 ₂ from the input video signal, is configured to outputs the converted enlarged image signal as a display video signal V2.

The video signal level detecting section 34 ₁ detects a video signal level from an input video signal, and the average level extracting sections 36 ₁ and 38 ₁ display the display panels 10 ₁ and 10 ₂ based on the detected video level. Video average levels VML1, VML
Extracting ML2, the comparator 40 _1, the maximum value by comparing the video average level VML1, VML2 (e.g. VML
Outputs 2), said control constant generating unit 42 _1, based on the comparator 40 _first output signal (e.g. VML2) to output a corresponding control constants (eg CP2) are constituted respectively.

[0035] The image signal level detection unit 34 ₂ detects the video signal level from the input video signal, said average level extraction unit 36 _2, 38 _2, the display panel 10 ₁ based on the video level detected, 10 ₂ Video average levels VML1, VML
Extracting ML2, the comparator 40 _2, the maximum value by comparing the video average level VML1, VML2 (e.g. VML
Outputs 2), said control constant generating unit 42 ₂ to output the corresponding control constant (eg CP2) based on the comparator 40 and _second output signal (e.g. VML2) are constituted respectively.

[0036] The control constant generating unit 42 ₁ (42 _2), for example, pre-output signals (eg V of the comparator 40 ₁ (40 ₂₎
ML1, VML2) as addresses and control constants CP1, C
Has the stored ROM (read only memory) of P2 as data, and is configured to output an output signal from the comparator 40 ₁ (40 ₂₎ (e.g. VML2) data corresponding to (CP2).

Next, the operation of FIGS. 4 and 5 will be described with reference to FIG. For convenience of explanation, the luminance of the input video signal is
As shown by a dotted line Y <b> 1 in FIG. 3, consider a case where the image increases linearly from the left end to the right end of the screen. In the control circuit 30 _1, display image extraction and conversion unit 32 ₁ extracts the video signal for the display panel 10 ₁ from the input video signal, and converts it to expanded image signal as a display video signal V1, the display allowed to display an image corresponding with the panel 10 _1. It also detects a video signal level from the video signal level detector 34 ₁ is the input video signal, the average level extraction section 3
6 ₁ and 38 ₁ are the display panel 10 based on the detected video level.
_1, 10 ₂ of the video average level VML1, extracts VML2, corresponding comparator 40 ₁ outputs the maximum value VML2 by comparing the two, control constant generation unit 42 ₁ is based on the output signal of the comparator 40 ₁ Control circuit 3 which outputs the obtained control constant CP2
In 0 _2, the display image extracting and converting unit 32 _2, and extracts a video signal for the display panel 10 ₂ from the input video signal, and outputs it as an enlarged image signal display video signal is converted into V2,
Allowed to display an image corresponding with the display panel 10 _2. It also detects a video signal level from the video signal level detector 34 ₂ is input video signal, the average level extraction unit 36 _2, 38 ₂
Extracts the video average levels VML1 and VML2 of the display panels 10 ₁ and 10 ₂ based on the detected video levels, and outputs
0 ₂ outputs the maximum value VML2 by comparing the two, and outputs a control constant CP2 corresponding based control constant generating unit 42 ₂ is the output signal of the comparator 40 ₂

[0038] As described above, the control constant output from the control circuit 30 _1, 30 ₂ to the drive circuit 14 _1, 14 _2, since both the large control constants CP2 power consumption suppression force, display panel 10 _1, 10 the power consumption of ₂ different, can be a drive circuit 14 _1, 14 ₂ to drive the state of the same control constant CP2. For this reason, the brightness of the display panels 10 ₁ and 10 ₂ is as shown in FIG.
As shown by the solid line Y3, the brightness increases linearly from the left end to the right end of the screen, and the brightness rapidly changes at the joint M of the display panels 10 ₁ and 10 ₂ as in the conventional example shown by the dashed line Y2. Can be prevented.

In the embodiment shown in FIG. 4, the control circuit 3
0 ₁ (30 ₂ ) is converted to a display video extraction / conversion unit 32 ₁ (32 ₂ ) and a video signal level detection unit 34 ₁ (3, as shown in FIG.
4 ₂ ), average level extraction units 36 ₁ , 38 ₁ (36 ₂ , 3
8 ₂ ), the comparator 40 ₁ (40 ₂ ) and the control constant generator 42 ₁
(42 ₂ ) to simplify the circuit configuration. However, the present invention is not limited to this. The video average level V of each of the display panels 10 ₁ and 10 ₂ is based on the input video signal.
ML1 and VML2 are obtained, and a control constant CPM (for example, CP) corresponding to the maximum value of the video average level (for example, VML2) is obtained.
What is necessary is just to output 2) to the corresponding drive circuit.

For example, the control circuit 30 ₁ (3
0 2 36 _{1 2),} 38 ₁ (36 _2, 38 ₂₎ and a comparator 40 ₁ (40 ₂₎ constituted by a single maximum average level extraction section, this maximum average level extraction section, the display panel 1
If the larger one of the image average levels VML1 and VML2 (for example, VML2) of 0 ₁ and 10 ₂ is extracted and output, the circuit configuration can be further simplified.

In the embodiment shown in FIGS. 1 and 4, some of the existing panel blocks (the former are display panels 10 ₁ , 10 ₂ ,
Drive circuits 14 ₁ and 14 ₂ and power consumption detection circuits 16 ₁ and 1
6 _2, the latter display panel 10 _1, 10 ₂ and the drive circuit 1
Although the case where 4 ₁ and 14 ₂ ) can be used has been described, the present invention is not limited to this, and the present invention can also be used when all of the existing panel blocks can be used as they are. FIGS. 6, 7, and 8 show an embodiment (corresponding to claims 1, 6, 7, and 8) in such a case, and the same parts as those in FIGS. 1 and 2 are denoted by the same reference numerals.

In FIG. 6, reference numeral 11 denotes a panel block combined body obtained by combining two panel blocks. The panel block combined body 11 has the same configuration as that of the conventional example shown in FIG. That is, 10 ₁ and 10 ₂ are display panels, 14
Reference numerals ₁ and 14 ₂ denote drive circuits, 16 ₁ and 16 ₂ denote power consumption detection circuits, and 18 ₁ and 18 ₂ denote first control circuits having a brightness adjustment function. The first control circuits 18 ₁ and 18 ₂ output corresponding control constants CP 1 and CP 2 based on the detection values K ₁ and K ₂ of the power consumption detection circuits 16 ₁ and 16 ₂ , and output the control constants CP 1 and CP 2. Is varied by a control signal input to the luminance adjustment terminal.

Reference numerals 50 ₁ and 50 ₂ denote second control circuits provided corresponding to the display panels 10 ₁ and 10 ₂ . As shown in FIG. 7, the second control circuit 50 ₁ (50 ₂ ) includes a display video extraction / conversion unit 32 ₁ (32 ₂ ) and a video signal level detection unit 34.
₁ (34 ₂ ), average level extraction units 36 ₁ , 38 ₁ (36 ₂ ,
38 ₂ ), the comparator 52 ₁ (52 ₂ ) and the control signal generator 5
4 ₁ (54 ₂ ).

The display video extracting / converting unit 32 ₁ (3)
2 _2), the video signal level detector 34 ₁ (34 _2), the average level extraction unit 36 _1, 38 ₁ (36 _2, 38 ₂₎ are the corresponding circuit of the control circuit 30 ₁ (30 ₂₎ of FIG. 5 Since the configuration is the same as that described above, the description is omitted. The comparator 52 ₁ outputs the video average level VML extracted by the average level extraction units 36 ₁ and 38 _1.
1, and outputs the difference between the maximum value and the target display panel 10 _first video average level VML1 of VML2. For example, VML1
Is compared with VML2, and the larger one (for example, VML2) is selected, and the difference between this value and the target value (VML1) (for example, VML1) is selected.
(L2-VML1). The comparator 52 _2, the mean level extraction section 36 _2, 38 ₂ in the extracted image average level VML2, VM
And it outputs the difference between the maximum value and the target display panel 10 _second video average level VML2 of L1. For example, VML1 and VML
2 and selects the larger one (eg, VML2), and the difference between this value and its own value (VML2) (eg, VML2-
VML2).

The control signal generation unit 54 _1, for example, a ROM and a D / A (digital / analog) conversion circuit mainly, reads the corresponding data difference signal DS1 output from the comparator 52 ₁ as an address, this The first control circuit 18 converts the signal into an analog signal and generates the control signal CS1.
By outputting the _first luminance adjustment terminal, and is configured to control the control constant to be output from the first control circuit 18 ₁ to the corresponding control constant (eg CP2). Therefore, the detection value control constant is not CP1 corresponding to the detected value K1 (e.g. 2) to be output from the first control circuit 18 ₁ K
2 corresponding to CP2 (for example, 8). Control signal generating unit _542, similarly to the control signal generation unit 54 _1, reads the corresponding data difference signal DS2 output from the comparator 52 ₂ as an address, the it as a control signal CS2 is converted into an analog signal by outputting the first control circuit 18 _{and second} luminance adjustment terminal, the first control circuit 18 ₂
Control constants (for example, CP
It is configured to control in 2). In this case (differential signal DS2 corresponding to a 0), the control constant to be output from the first control circuit 18 ₂ does not change next to CP2 corresponding to the detected value K2.

Next, the operation of FIGS. 6 and 7 will be described with reference to FIG. For convenience of explanation, the luminance of the input video signal is
As shown by a dotted line Y <b> 1 in FIG. 3, consider a case where the image increases linearly from the left end to the right end of the screen. In the second control circuit 50 ₁ corresponding to the display panel 10 _1, comparator 52 _1, the maximum value VM compares the video average level VML1, VML2 the average level extraction unit 36 _1, 38 ₁ and extracted
Select L2, and outputs a difference signal DS1 of the video average level VML1 the target display panel 10 _1, the control signal generating unit 5
4 ₁ is a control signal CS1 corresponding to the difference signal DS1
To the first control circuit 18 ₁ , and the first control circuit 18 ₁
The control constant output from the control circuit 14 ₁ to the drive circuit 141 is the same as that of the conventional CP.
It is changed from 1 to CP2, the power consumption of the display panel 10 ₁ This control constant CP2 is controlled. In the second control circuit 50 ₂ corresponding to the display panel 10 _2, comparators 40
_2, the maximum value by comparing the average level extraction unit 36 _2, 38 ₂ in the extracted image average level VML1, VML2 VML2
Select, the target display panel 10 ₂ video average level VM
A difference signal DS2 from L2 is output, and the control signal generator 54 ₂
Since but it outputs a control signal CS2 corresponding based on the difference signal DS2 (corresponding to 0) to the first control circuit 18 _2, control signal output from the first control circuit 18 ₂ to the drive circuit 14 ₂ and CP2 conventional example unchanged, the power consumption of the display panel 10 ₂ by the control constant CP2 is controlled.

As described above, the second control circuits 50 ₁ and 50 ₂
, The control constants output to the drive circuits 14 ₁ and 14 ₂ are both CP2. Therefore, even if the power consumption of the display panels 10 ₁ and 10 ₂ is different, the drive circuits 14 ₁ and 14 ₂ have the same control constant CP.
2 driving states. Therefore, the display panel 10 ₁ ,
The luminance of 10 ₂ linearly increases from the left end to the right end of the screen as shown by the solid line Y3 in FIG. 3, and the seam M of the display panels 10 ₁ and 10 ₂ as in the conventional example shown by the dashed line Y2.
Can prevent a sudden change in brightness.

[0048] Figure 1, Figure 4, in the example embodiment of FIG. 6, the control constant CP2 video average level corresponding to the maximum of the display panel 10 ₂ (an example of a CPM), the drive from the control circuit circuit 1
4 _1, 14 have been arranged to output to the _2, the present invention is not limited thereto, CPM (e.g., 8) driving a larger control constant power consumption suppression force CPMA (eg 9) circuit 14
_1, it can also be utilized for that to output to 14 _2.

[0049] Figure 4, in the example embodiment of FIG. 6, provided a control circuit for the number of panel blocks, as can individual control panels block, dividing the display area (e.g., 9 by the display panel 10 ₁ to 10 ₉ division display some areas of the area) (e.g. area of the display panel 10 _first panel block)
Can be excluded from the control target, but the present invention is not limited to this. The present invention can also be used in a case where there is no display panel to be excluded from the control and the entire display panel is the control target.

For example, the second control circuit 50 ₁ (5
0 ₂ ) to the second control circuit 50a ₁ (50
can be further simplified circuit configuration is changed to a _2). That is, the second control circuit 50a ₁ (50a ₂ )
The display image extraction and conversion unit 32 ₁ (32 _2), the video signal level detector 34 ₁ (34 _2), the maximum average level extraction section 56
Configuring _one (56 ₂₎ and a control signal generation unit 58 ₁ (58 _2). The display image extraction and conversion unit 32 ₁ (32 _2), the video signal level detector 34 ₁ (34 _2), the control circuit 30 of FIG. 7
₁ (30 ₂ ), the corresponding configuration is the same as that of the circuit. The maximum average level extraction unit 56 ₁ is configured to output the video average level VML1 of the display panels 10 ₁ and 10 ₂ based on the video level detected by the video signal level detection unit 34 ₁ .
Extracting the maximum value VML2 of VML2, the control signal generation unit 58 _1, for example, a ROM and a D / A conversion circuit, the maximum value V extracted in the maximum average level extraction unit 56 ₁
A control signal CS1 is output to the brightness adjustment terminal of the first control circuit 18 ₁ based on ML2 and a detection value K1 from the power consumption detection circuit 16 _1, and a corresponding control constant CP2 is output from the first control circuit 18 ₁ It is configured to be confused.
The maximum average level extraction unit 56 _2, on the basis of the video level detected by the image signal level detection unit 34 ₂ extracts the maximum value VML2 in the video average level VML1, VML2, the control signal generator 58 ₂ , the control signal based on the detection value K2 from maximum average level extraction unit 56 maximum VML2 the power detecting circuit 16 ₂ extracted with ₂ CS
Output 2 to the first control circuit 18 _{and second} luminance adjustment pin is configured to allowed to output a control constant CP2 corresponding from the first control circuit 18 _2.

In the embodiment of FIGS. 1, 4 and 6, the control circuit corresponding to each display panel has a constant control constant CPM.
(E.g. CP2 (e.g. 8)) or by outputting the corresponding drive circuits CPMa (e.g. 9), with the power consumption of the display panel 10 _1, 10 ₂ is equal to or less than the prescribed value, the display panel 10 _1, 10 ₂ Has been described so as to prevent a sudden change in brightness at the seam M, but the present invention is not limited to this, and the control circuit initially performs individual control corresponding to each drive circuit. Output a constant, and a common control constant CPM or CP
A configuration in which a control constant approaching Ma is output to each drive circuit can also be used. With this configuration, it is possible to prevent the luminance of the display panel from changing suddenly or frequently.

For example, the present invention can also be used when the function of the control circuit 30 ₁ (30 ₂ ) in FIG. 4 is changed as follows. That is, (modified circuit 30 ₁₎ control circuit in Figure 4, initially the display panel 10 _first video average level VM
The control constant CP1 corresponding to L1 output to the drive circuit 14 _1, and outputs a control constant approaches the control constants CP2 over time to the drive circuit 14 _1. Brightness of the display panel 10 ₁ can be prevented from changing abruptly or frequently. Incidentally, (modified circuit 30 ₂₎ the control circuit of Figure 4 outputs a control constant CP2 corresponding to the video average level VML2 of the display panel 10 ₂ from the first drive circuit 14 _2.

In the above embodiment, the case where two display panels forming one screen and two driving circuits are correspondingly described has been described. However, the present invention is not limited to this.
Needless to say, the present invention can be applied to a case where three or more display panels form one screen and three or more drive circuits are correspondingly provided.

[0054]

According to the first aspect of the present invention, a video average level of each display panel is obtained based on an input video signal, and a control constant CPM corresponding to the display panel having the maximum video average level is n.
A control circuit for outputting the control constant CPM (for example, CP2) corresponding to the display panel having the largest average image level to the n drive circuits. Is less than or equal to the specified value, and even if the power consumption of n display panels is different, n
The drive circuits can be driven by the same control constant CPM. Therefore, it is possible to prevent a sudden change in brightness at the joint of the display panel as in the conventional example.

According to a second aspect of the present invention, in the first aspect of the present invention, there are provided n power consumption detecting circuits for individually detecting the power consumption of each display panel, and the control circuit controls each of the display panels based on an input video signal. A video average level of the display panel is obtained, and a control constant CPM of a detection value corresponding to the display panel having the maximum video average level among the detection values of the n power consumption detection circuits.
(E.g., CP2) is output to all of the n drive circuits as a common control constant, so that the power consumption of each display panel is equal to or less than a specified value and the power consumption of the n display panels is different. Even so, the n drive circuits can be driven in the same control constant CPM.

According to a third aspect of the present invention, in the second aspect, the control circuit comprises a video signal level detecting section, n average level extracting sections, a comparator, and a control constant generating section, and the n average levels The level extractor obtains the image average level of each display panel, compares the image average level with a comparator and outputs the maximum value, and the control constant generator generates the maximum value among the values detected by the n power consumption detection circuits. Since the control constant CPM of the detection value corresponding to the output signal of the comparator is generated and output as a common control constant to all of the n drive circuits, the configuration of the control circuit can be simplified.

According to a fourth aspect of the present invention, in the first aspect of the present invention, the control circuit determines a video average level of each display panel based on an input video signal, and controls a control constant corresponding to the display panel having the maximum video average level. Since it is composed of n control circuits that output the CPM to the corresponding drive circuit, the power consumption of each display panel can be reduced to a specified value or less, and even if the power consumption of the n display panels is different, n drive circuits are used. The circuit can be driven with the same control constant CPM.

According to a fifth aspect of the present invention, in the fourth aspect, each control circuit comprises a video signal level detecting section, n average level extracting sections, a comparator and a control constant generating section, and the n average levels are controlled. The level extractor obtains the image average level of each display panel, compares these image average levels with a comparator and outputs the maximum value. The control constant generator generates a control constant CPM based on the output signal of the comparator. Since it is generated and output to the corresponding drive circuit, the configuration of the n control circuits can be simplified.

According to a sixth aspect of the present invention, in the first aspect of the present invention, there are provided n power consumption detecting circuits, and the control circuit comprises n first control circuits having a luminance adjustment terminal, and a first control circuit. And a second control circuit that outputs a control signal to the luminance adjustment terminal of the control panel, obtains an image average level of each display panel, and controls the difference between the maximum value and the image average level of the target display panel. Since the signal is output to the luminance adjustment terminal of the first control circuit and the control constant output from the first control circuit to the drive circuit is controlled, an existing panel block combination can be used.

According to a seventh aspect of the present invention, in the sixth aspect, each of the n second control circuits includes a video signal level detection section, n average level extraction sections, a comparator, and a control signal generation section. Composes and compares the video average levels obtained by each average level extraction unit, outputs a difference signal between the maximum value of the video average level and the video average level of the target display panel, and generates a control signal corresponding to the difference signal Then, a control constant output to the luminance adjustment terminal of the first control circuit and output from the first control circuit to the drive circuit is controlled, so that the configuration of the second control circuit can be simplified.

According to an eighth aspect of the present invention, in the invention of the sixth aspect, each of the n control circuits comprises a video signal level detecting section, a maximum level extracting section, and a control signal generating section. A maximum value among the levels is obtained, a control signal is generated based on the maximum video average level and an output control constant of the first control circuit, and the control signal is output to a brightness adjustment terminal of the first control circuit, and is driven from the first control circuit. Since the control constant output to the circuit is controlled, the configuration of the second control circuit can be further simplified.

According to a ninth aspect of the present invention, an image average level of each display panel is obtained based on an input image signal, a control constant CPM corresponding to the display panel having the maximum image average level is obtained, and power consumption is calculated from the control constant CPM. A control circuit for generating a control constant CPMa having a large suppression force and outputting the control constant CPMa to n driving circuits is provided, and control corresponding to a display panel having a maximum image average level (maximum power consumption). Since the control constant CPMa having a larger power consumption suppressing power than the constant CPM (for example, CP2) is output to the corresponding drive circuit, the power consumption of each display panel becomes equal to or less than a specified value, and the power consumption of the n display panels is reduced. Even if different, the n driving circuits can be driven in the same control constant CPMa. For this reason, it is possible to prevent a sudden change in brightness at the seam of the display panel.

According to a tenth aspect, in the ninth aspect, there are provided n power consumption detecting circuits, and the control circuit comprises:
A control constant CPM of a detection value corresponding to the display panel having the largest image average level among the detection values of the n power consumption detection circuits is obtained, and a control constant CPMa having a larger power consumption suppressing power than the control constant CPM is created. , This control constant CP
Since Ma is output to the n driving circuits as a common control constant, the power consumption of each display panel becomes equal to or less than a specified value, and even if the power consumption of the n display panels is different, n The driving circuit can be driven with the same control constant CPMa.

According to an eleventh aspect of the present invention, an image average level of each display panel is obtained based on an input image signal, and a control constant CPM corresponding to the display panel having the maximum image average level is obtained. .., CPn corresponding to the average level are output to the drive circuit, and n control circuits are output to the drive circuit for outputting control constants approaching the common control constant CPM over time. Therefore, the power consumption of each display panel can be reduced to a specified value or less, and the n drive circuits can be driven with the same control constant CPM over time, and the luminance of the display panel is prevented from changing rapidly or frequently. it can.

According to a twelfth aspect of the present invention, a video average level of each display panel is determined based on an input video signal, a control constant CPM corresponding to the display panel having the maximum video average level is determined, and power consumption is calculated from the control constant CPM. A control constant CPMa having a large suppressing force is created, and initially, control constants CP1, CP2,..., CP corresponding to the average image level of each display panel.
n is output to the drive circuit, and n control circuits are provided to output a control constant approaching the common control constant CPMa to the drive circuit over time, so that the power consumption of each display panel is reduced to a specified value or less. In addition, the n driving circuits can be driven with the same control constant CPMa over time, and the luminance of the display panel can be prevented from changing suddenly or frequently.

[Brief description of the drawings]

FIG. 1 is a block diagram showing a first embodiment of a display device according to the present invention.

FIG. 2 is a block diagram showing a specific example of a control circuit in FIG.

FIG. 3 is a luminance characteristic diagram for explaining the operation of FIG. 1;

FIG. 4 is a block diagram showing a second embodiment of the display device according to the present invention.

FIG. 5 is a block diagram showing a specific example of a control circuit in FIG. 4;

FIG. 6 is a block diagram showing a third embodiment of the display device according to the present invention.

FIG. 7 is a block diagram illustrating a specific example of a second control circuit in FIG. 6;

8 is a block diagram showing a specific example in which a part of the second control circuit in FIG. 6 is changed.

FIG. 9 is a block diagram showing a conventional example.

FIG. 10 is a luminance characteristic diagram illustrating the operation of FIG. 9;

[Explanation of symbols]

10 ₁ , 10 ₂ ... display panel, 12 ₁ , 12 ₂ , 32 ₁ ,
32 ₂ … display video extraction / conversion unit, 14 ₁ , 14 ₂ … drive circuit, 16 ₁ , 16 ₂ … power consumption detection circuit, 18 ₁ ,
18 ₂ ... first control circuit, 20, 30 ₁ , 30 ₂ ... control circuit, 22 ₁ , 22 ₂ , 34 ₁ , 34 ₂ ... video signal level detector, 24 ₁ , 24 ₂ , 36 ₁ , 36 ₂ , 38 ₁ , 38 ₂ …
Average level extractor, 26, 40 ₁ , 40 ₂ , 52 ₁ , 5
2 ₂ ... Comparator, 28, 42 ₁ , 42 ₂ .
50 ₁ , 50 ₂ ... second control circuit, 50 a ₁ , 50 a ₂ ...
A circuit obtained by modifying the circuit configuration of the second control circuits 50 ₁ and 50 ₂ ;
54 ₁ , 54 ₂ , 58 ₁ , 58 ₂ ... control signal generator, 5
6 ₁ , 56 ₂ … Maximum average level extractor, CS1, CS2
... Control signal, CP1 ... Control constant, CP2 ... Control constant (an example of CPM), CPM ... Control constant corresponding to the display panel with the largest power consumption, CPMa ... Control constant C
K1 and K are control constants with greater power consumption suppression power than PM.
2: Detection value, M: Seam (border) of display panel, V
1 ... display video signal for the display panel 10 _1, V2 ... display video signal for the display panel _{10 2, Y1, Y2, Y3} ...
Brightness level line.

Claims (12)

[Claims] 1. An image display apparatus comprising: n (n is an integer of 2 or more) display panels forming one screen; and n drive circuits for individually driving each display panel based on an input video signal. In a display device in which a control constant CP for suppressing power consumption is output to n driving circuits so that the power consumption of each display panel becomes equal to or less than a specified value, an image average of each display panel is calculated based on the input video signal. A display device comprising: a control circuit for determining a level and outputting a control constant CPM corresponding to a display panel having a maximum image average level to the n drive circuits. 2. The apparatus according to claim 1, further comprising: n power consumption detection circuits for individually detecting power consumption of each display panel, wherein the control circuit obtains an image average level of each display panel based on an input video signal. And outputting a control constant CPM of a detection value corresponding to a display panel having a maximum image average level among detection values detected by the power consumption detection circuit to all of the n driving circuits as a common control constant. The display device according to 1. 3. A control circuit comprising: a video signal level detector for detecting a video level of an input video signal; and n averages for obtaining a video average level of each display panel based on a detection value of the video signal level detector. A level extraction unit, a comparator that compares the video average levels obtained by each average level extraction unit and outputs a maximum value, and a signal corresponding to the output signal of the comparator among the detection values of the n power consumption detection circuits. Control constant C of detected value
The display device according to claim 2, further comprising a control constant generation unit that generates PM and outputs the generated PM as a common control constant. 4. The control circuit obtains an image average level of each display panel based on an input image signal, and outputs a control constant CPM corresponding to the display panel having the maximum image average level to a corresponding drive circuit. The display device according to claim 1, wherein the display device serves as a control circuit. 5. Each of the n control circuits includes a video signal level detecting section for detecting a video level of an input video signal, and a video average level of each display panel based on a detected value of the video signal level detecting section. N average level extraction units to be obtained, a comparator for comparing the video average levels obtained by each average level extraction unit and outputting a maximum value, and a control constant for generating a control constant CPM based on an output signal of the comparator The display device according to claim 4, further comprising a generation unit. 6. An apparatus according to claim 1, further comprising: n power consumption detecting circuits for individually detecting power consumption of each display panel, wherein the control circuit outputs a corresponding control constant based on a detection value of each power consumption detecting circuit. An n number of first control circuits whose output control constants are varied by a control signal input to a brightness adjustment terminal; and a video average level of each display panel is determined based on an input video signal. 2. The display device according to claim 1, further comprising: n second control circuits that output a control signal corresponding to a difference from an image average level of the display panel to a luminance adjustment terminal of the first control circuit. 7. Each of the n second control circuits includes a video signal level detector for detecting a video level of an input video signal, and a video average of each display panel based on a detection value of the video signal level detector. A comparator for comparing the n average level extraction units for obtaining the levels with the video average levels obtained by the respective average level extraction units and outputting a difference signal between the maximum value of the video average level and the video average level of the target display panel 7. The display device according to claim 6, further comprising: a control signal generation unit configured to generate a control signal to be output to the first control circuit based on an output signal of the comparator. 8. Each of the n control circuits includes a video signal level detector for detecting a video level of an input video signal, and a video average level of each display panel based on a detection value of the video signal level detector. A maximum average level extractor for obtaining the maximum image average level, and control for outputting to the first control circuit based on the maximum image average level obtained by the maximum average level extractor and the output control constant of the first control circuit. The display device according to claim 6, further comprising a control signal generation unit that generates a signal. 9. An n display panel forming one screen and n driving each display panel individually based on an input video signal.
A display device comprising: n driving circuits; and outputting a control constant CP for suppressing power consumption to the n driving circuits so that the power consumption of each display panel is equal to or less than a specified value.
An image average level of each display panel is obtained based on the input image signal, a control constant CPM corresponding to the display panel having the maximum image average level is obtained, and a control constant CPMa having a larger power consumption suppressing power than the control constant CPM is created. And a control circuit for outputting the control constant CPMa to the n drive circuits. 10. An image forming apparatus comprising: n power consumption detecting circuits for individually detecting power consumption of each display panel; a control circuit calculates a video average level of each display panel based on an input video signal; The control constant CPM of the detection value corresponding to the display panel having the largest image average level among the detection values by the power consumption detection circuit is obtained, and a control constant CPMa having a larger power consumption suppressing power than the control constant CPM is created. 10. The display device according to claim 9, wherein the control constant CPMa is output to the n driving circuits as a common control constant. 11. N display panels forming one screen,
N driving circuits for individually driving each display panel based on an input video signal, and outputting a control constant CP for suppressing power consumption to the n driving circuits to reduce the power consumption of each display panel. In a display device which is not more than a prescribed value, an image average level of each display panel is obtained based on the input image signal, and a control constant CPM corresponding to the display panel having the maximum image average level is obtained. Control constants CP1, CP2 corresponding to the average image level of the panel,
.., N control circuits for outputting CPn to each of the corresponding drive circuits and outputting a control constant approaching the common control constant CPM over time to each of the corresponding drive circuits. A display device characterized by the above-mentioned. 12. A display device comprising: n display panels forming one screen;
N driving circuits for individually driving each display panel based on an input video signal, and outputting a control constant CP for suppressing power consumption to the n driving circuits to reduce the power consumption of each display panel. In a display device having a specified value or less, a video average level of each display panel is obtained based on the input video signal, and a control constant CPM corresponding to the display panel having the maximum video average level is obtained. Create a control constant CPMa with greater power consumption suppression power,
Initially, control constants CP1, CP2,..., CPn corresponding to the image average level of each display panel are output to each of the corresponding drive circuits, and control constants approaching the common control constant CPMa with the passage of time. A display device comprising: n control circuits that output signals to respective drive circuits.