KR101839327B1 - Backlight control circuit and method, lcd applyed thereof - Google Patents

Abstract

The present invention discloses a local dimming control circuit and a liquid crystal display device. More particularly, the present invention relates to a liquid crystal display device to which a local dimming method for dividing a screen into a plurality of logical blocks is applied, a dimming control circuit and method provided therein, and a liquid crystal display device using the same.
A dimming control circuit according to an embodiment of the present invention receives a modulated video signal for local dimming driving and receives at least one of a plurality of logical blocks obtained by dividing a screen into a plurality of blocks, A peak luminance determination unit for generating a peak luminance signal for controlling the luminance signal to have a luminance value; a block position calculation unit for analyzing the modulated video signal and generating a position signal, And a peak luminance adjustment unit for compensating for the peak luminance signal corresponding to the position signal.
According to the embodiment of the present invention, by driving different peak luminance values corresponding to the positions of the logical blocks on the screen, not only the power consumption is reduced as compared with the peak luminance driving for the entire screen, It is possible to provide a backlight driving circuit and a driving method of the apparatus.

Description

BACKGROUND OF THE INVENTION Field of the Invention [0001] The present invention relates to a dimming control circuit and a liquid crystal display (LCD)

The present invention relates to a local dimming control circuit and a liquid crystal display device, and more particularly, to a liquid crystal display device to which a local dimming method for dividing a screen into a plurality of logical blocks is applied, a dimming control circuit and method therefor, To a liquid crystal display device to which the present invention is applied.

Unlike the flat panel display devices using other self-luminous elements, the liquid crystal display device is a light receiving and emitting device that displays an image by using external light or a backlight as a separate light source.

The quality of an image implemented by such a liquid crystal display device is largely influenced by a contrast ratio. To improve this, backlight dimming, which is one of the proposed techniques, This technique improves the contrast ratio by adaptively controlling the luminance.

The above-described backlight dimming method is divided into a global dimming method for adjusting the brightness of the entire screen and a local dimming method for locally adjusting the brightness of the screen. The global dimming method is a backlight control method of adjusting the brightness of the entire display surface to improve the dynamic contrast measured between the previous frame and the next frame. The local dimming method is a method of adjusting the brightness of the display surface in a local To thereby improve the static contrast which is difficult to be improved by the global dimming method.

In particular, in order to maximize the efficiency of the above-described local dimming method, by controlling the backlight of some logical blocks so as to emit light with a higher luminance than the full backlight state, i.e., full-white state, A peak luminance driving method has been proposed in which the contrast ratio is improved and the image quality is improved.

FIGS. 1A and 1B are views schematically illustrating a brightness distribution and an inter-block luminance deviation on a screen of a liquid crystal display according to a conventional local dimming method and a peak luminance driving technique.

Referring to the drawings, FIG. 1A shows an example of a conventional local dimming driving method in which a brightness deviation of a backlight between blocks is varied according to an image on one screen. In this case, as shown in FIG. 1B, the peak luminance driving is performed so as to have a peak luminance higher than the full-white luminance of 100% for a block displaying a high luminance in one image, The contrast ratio of the entire image is further improved.

That is, in the illustrated example, when the luminance of the block corresponding to the row V is compared, the luminance of each block does not exceed 100% in the conventional local dimming driving, but in the peak luminance driving, To drive the backlight.

However, the above-described peak luminance driving technique has a problem that the backlight of specific blocks requires a larger amount of current than the conventional local dimming method, thereby increasing the power consumption during backlight driving.

In addition, according to the peak luminance driving technique, pixels in a block driven with a peak luminance have a problem of gray scale clustering, which is difficult to identify when displaying an image with a high gray scale.

SUMMARY OF THE INVENTION The present invention has been conceived to solve the above-described problems, and it is an object of the present invention to reduce power consumption by peak luminance driving in a local dimming type liquid crystal display device in which a screen is divided into a predetermined number of logical blocks, And it is an object of the present invention to provide a backlight driving circuit and a driving method of a liquid crystal display device.

It is another object of the present invention to provide a backlight driving circuit and a driving method of a liquid crystal display device which improves gradation accumulation occurring in a peak luminance driving block when a peak luminance of a backlight is driven.

In order to achieve the above object, a dimming control circuit according to a preferred embodiment of the present invention receives a modulated video signal for local dimming driving, and receives at least one of a logical block obtained by dividing a screen into a plurality of screens, a peak luminance determining unit for generating a peak luminance signal for controlling the luminance to be higher than that of the full-white driving; A block position calculation unit for analyzing the modulated video signal and generating a position signal that calculates the position of each block on the screen; And a peak luminance adjusting unit for compensating for the peak luminance signal corresponding to the position signal.

Wherein the position signal includes a value for a distance of the corresponding block from the reference with respect to the center of the screen.

And the peak luminance adjustment unit has a smaller degree of compensation of the peak luminance signal as the separation distance is larger.

In order to achieve the above object, a liquid crystal display device to which a dimming control circuit according to a preferred embodiment of the present invention is applied is a local dimming-type liquid crystal display device that drives backlights at different brightness levels among a plurality of divided logical blocks , A liquid crystal panel; A gate and a data driver for driving the liquid crystal panel; A timing controller for generating control signals of the gate and the data driver, receiving and receiving image signals from an external system, and arranging and converting the signals; Modulates the video signal to correspond to the block, and generates a peak luminance signal and a dimming signal for controlling at least one of the blocks to have a luminance value larger than that in full-white driving A dimming control circuit for compensating the peak luminance signal according to the position of the peak luminance driving block and applying the compensated peak luminance signal to the dimming signal; A backlight driver for driving the backlight in response to the compensated dimming signal; And a backlight for providing light to the liquid crystal panel under the control of the backlight driver.

Wherein the dimming control circuit comprises: a peak luminance determination unit receiving a video signal modulated for local dimming driving to generate the peak luminance signal; A block position calculation unit for analyzing the modulated video signal and generating a position signal that calculates the position of each block on the screen; And a peak luminance adjusting unit for compensating for the peak luminance signal corresponding to the position signal.

Wherein the position signal includes a value for a separation distance of the block from the reference with respect to the center on the screen.

And the peak luminance adjustment unit has a smaller degree of compensation of the peak luminance signal as the separation distance is larger.

Wherein the dimming control circuit includes: an image analyzer for receiving and analyzing the image signal to define a block and calculating a local dimming driving luminance value for each block; A data modulator for aligning and modulating the image signal; A dimming determining unit for mapping the local dimming driving brightness value to a preset dimming curve to generate the dimming signal; And a dimming control unit for applying the compensated peak luminance signal to the dimming signal.

The dimming curve is implemented in the form of a look-up table (LUT).

In order to achieve the above object, a dimming control method according to a preferred embodiment of the present invention includes receiving a modulated video signal for local dimming driving and converting at least one of a logical block into a full- generating a peak luminance signal that controls a luminance value to be greater than a luminance value during full-white driving; Analyzing the modulated video signal to generate a position signal that calculates the position of each block on the screen; And compensating the peak luminance signal corresponding to the position signal.

According to the embodiment of the present invention, by driving different peak luminance values corresponding to the positions of the logical blocks on the screen, not only the power consumption is reduced as compared with the peak luminance driving for the entire screen, It is possible to provide a backlight driving circuit and a driving method of the apparatus.

FIGS. 1A and 1B are views schematically illustrating a brightness distribution and an inter-block luminance deviation on a screen of a liquid crystal display according to a conventional local dimming method and a peak luminance driving technique.
2 is a view schematically showing the entire structure of a liquid crystal display device according to an embodiment of the present invention.
3 is a diagram showing a structure of a dimming control circuit according to an embodiment of the present invention.
FIG. 4A is a diagram illustrating an example of dividing a screen of a liquid crystal display according to an exemplary embodiment of the present invention into predetermined logical blocks, and FIG. 4B is a view illustrating a degree of compensation of a peak luminance value according to the position of each block .
5 is a diagram schematically showing luminance distribution and inter-block luminance deviation on a screen of a liquid crystal display according to the dimming control method of the present invention.
6 is a diagram illustrating a dimming control method of a liquid crystal display according to a preferred embodiment of the present invention.

Hereinafter, a backlight driving circuit and a driving method of a liquid crystal display according to a preferred embodiment of the present invention will be described with reference to the drawings.

2 is a view schematically showing the entire structure of a liquid crystal display device according to an embodiment of the present invention.

As shown in the figure, a liquid crystal display device according to an embodiment of the present invention includes a liquid crystal display panel 10, a timing controller 30, a gate driver 50, a data driver 60, a dimming control circuit 70, (80) and a backlight (90).

Specifically, the liquid crystal display panel 10 includes two transparent substrates bonded together with a predetermined distance therebetween, and a liquid crystal layer interposed therebetween. In the two substrates, a plurality of gate lines GL and a plurality of data lines DL are vertically crossed on the lower substrate, and a plurality of pixel regions are defined as a matrix in accordance with the intersection structure. In each pixel region, a thin film transistor (TFT) as a switching element, a pixel electrode connected to one electrode of the thin film transistor, a liquid crystal cell Clc, and a storage capacitor Cst are arranged.

A color filter for displaying three primary colors, a black matrix (BM) for partitioning each pixel region, and a common electrode are formed on the upper substrate. Here, the common electrode is formed on the upper substrate in the vertical field driving mode, that is, in the TN (Twisted Nematic) mode, VA (Vertical Alignment) mode and the like. In the IPS (InPlane Switching) mode, Are alternately arranged in parallel with one pixel electrode. A polarizing plate for polarizing light entering and leaving the light source is attached to the front and rear surfaces of the liquid crystal display panel 10.

The timing controller 30 receives a digital data signal DATA and various control signals DCLK, Hsync, and Vsync from an external system 25 that provides a video source, and aligns and converts the data signal DATA to various control signals And supplies a gate control signal GCS and a data control signal DCS to the gate and data drivers 50 and 60 and a video signal DATA to the dimming control circuit 70. The timing controller 30 receives the video signal DATA ', which the dimming control circuit 70 has aligned and converted, and supplies the video signal DATA' to the data driver 60.

The timing controller 30 receives the signals described above through an interface with the external system 25. The LVDS (Low Voltage Differential Signal) interface and the TTL interface are used as the interface. Such an interface may be configured as a single chip embedded in the timing controller 30.

The gate driver 50 turns on / off the thin film transistors (TFTs) arranged on the liquid crystal panel 10 in response to the gate control signal GCS input from the timing controller 30, .

The gate driver 50 includes a plurality of shift registers to generate a gate driving signal VG and supply the gate driving signal VG to a plurality of gate gate lines GL. 10 are turned on / off so that a video signal supplied from the data driver 60 is applied to a pixel connected to each thin film transistor TFT.

Here, the gate control signal GCS input to the gate driver 50 includes a gate start pulse (GSP), a gate shift clock (GSC), a gate output enable (GOE) The gate driver 50 shifts the GSP according to the GSC among the input gate control signals GCS and sequentially supplies the gate driving signals VG to the plurality of gate lines GL. Here, the pulse width of the gate driving signal VG is controlled according to GOE.

The data driver 60 selects the reference voltages of the input video signal DATA 'corresponding to the data control signal DCS input from the timing controller 30 and supplies the selected reference voltage to the liquid crystal display panel 10 And controls the rotation angle of the liquid crystal molecules.

The data control signal DCS includes a source start pulse (SSP), a source shift clock (SSC), and a source output enable (SOE) signal. And converts the video signal DATA 'input from the timing controller 30 into an analog voltage form. Specifically, the data driver 60 latches the video signal DATA 'input from the timing controller 50 in response to the SSC, and supplies a gate driving signal The video signal for one horizontal line is supplied to the data line DL in every one horizontal period in which the video signal VG is supplied.

At this time, the data driver 60 selects a positive or negative gamma voltage having a predetermined level according to the gradation value of the aligned and converted video signal DATA ', and supplies the selected gamma voltage to each data line DL .

 The dimming control circuit 70 analyzes the video signal DATA input from the timing controller 30 to determine a backlight luminance value corresponding to each logical block to generate a dimming signal DIM. In addition, the dimming control circuit 70 calculates the degree of luminance reduction of a specific pixel by the dimming signal DIM, and converts the video signal DATA into the data signal in consideration of this. The above-described conversion process of the image signal (DATA) is for compensating for the luminance drop due to the local dimming driving on the liquid crystal side rather than on the backlight side. Pixels in one block can display different gradations, A process of comparing the amount of light at the time of driving by the local dimming and the amount of light at the time of non-dimming and generating the converted video signal DATA 'according to the difference. Accordingly, the dimming control circuit 70 adaptively modulates the input video signal DATA.

The dimming control circuit 70 determines the peak luminance value for each block and applies it to the dimming signal so that the degree of the peak luminance value is set differently according to the relative position of the block on the screen, ').

Particularly, the dimming control circuit 70 analyzes the inputted video signal (DATA) after generation of the dimming signal (DIM) to determine the position of each block on the screen, The peak luminance value is set to be gradually smaller. That is, the dimming control circuit 70 of the present invention is characterized in that the peak luminance value is varied according to the position of the block, instead of determining the peak luminance value according to the image form.

The dimming control circuit 70 determines the position of each logical block on the screen, calculates the distance between the central region of the screen and each block, and adjusts the peak luminance value according to the distance. The adjusted peak luminance value is applied to the dimming signal (DIM ') and supplied to the backlight driver 80.

This is because the observer obtains an improved contrast ratio when the luminance of the center region of the screen is higher than the luminance of the surrounding region, and the color characteristic also appears to be lighter than the conventional one.

A more detailed description of the structure of the dimming control circuit 70 will be described later.

The backlight driver 80 has a PWM (Pulse) mode which determines the lighting and blinking period of the backlight according to the duty ratio corresponding to the dimming signal DIM 'corrected for each logical block input from the dimming control circuit 70 Width Modulation) to drive the backlight. The backlight driver 80 may be implemented by a plurality of inverters driving each light source divided into a plurality of blocks.

The backlight 90 includes a plurality of light sources, and the plurality of light sources are again grouped into a plurality of groups, and the planar light source irradiated to the liquid crystal display panel 10 is divided into a plurality of logical blocks. The backlight 90 may be implemented as either a direct type or an edge type. Particularly in the case of the metering type, it is not easy to divide the screen into a predetermined number of blocks. However, it is also possible to provide one light source in each of the X and Y axes of the four sides of the liquid crystal display panel 10, The local dimming may be implemented by controlling the lighting of the light source and superimposing on the screen so that the luminance is increased in the corresponding block. As the light source of the backlight 90, a light emitting diode (LED), which is a point light source favorable for blocking, is preferably used.

The optical member 95 is provided on the front surface of the backlight 90 and on the rear surface of the liquid crystal display panel 10 in order to increase the efficiency of the light emitted from the backlight 90, A light guide plate and a prism sheet for guiding light emitted from a light source, and a reflector or the like as a back surface of the backlight 90.

The liquid crystal display according to this structure can variably apply the peak luminance driving technique according to the position of each block by the dimming control circuit described above, thereby providing an observer with an image having an improved contrast ratio. Hereinafter, the structure of the dimming control circuit according to the preferred embodiment of the present invention will be described with reference to the drawings.

3 is a diagram showing a structure of a dimming control circuit according to an embodiment of the present invention.

1, the dimming control circuit of the present invention includes an image analysis unit 110, a dimming determination unit 120, a data modulation unit 130, a peak luminance processing unit 150, a dimming control unit 170, .

The image analyzing unit 110 divides a screen of the liquid crystal display panel into a plurality of virtual logical block units divided into a matrix form through a video signal input from an external system and analyzes each block to calculate a local dimming driving luminance value per block .

The dimming determining unit 120 generates a dimming signal DIM by mapping the driving brightness values analyzed by the image analyzing unit 110 to predetermined dimming curves on a one-to-one basis. The dimming curve can be implemented in the form of a look-up table (LUT).

The data modulator 130 modulates the local dimming light amount and the non-dimming light amount of each block corresponding to the block local dimming driving luminance value calculated by the image analyzer 110 And modulates the video signal DATA according to the difference to generate a video signal DATA '.

The peak luminance processing unit 150 generates a peak luminance signal PK for each block corresponding to the modulated video signal DATA 'generated by the data modulation unit 130. [ The above-mentioned peak luminance signal PK is a signal for controlling the backlight lamp to have a luminance value larger than that in the full-white driving in which the entire backlight lamp is lit for a specific block. In addition, the peak brightness processor 150 determines the positions where the respective logical blocks are arranged on the screen corresponding to the modulated video signal DATA ', calculates the distances between the blocks in the screen central region, And supplies the compensated peak luminance signal PK 'to the dimming control unit 170. The dimming control unit 170 generates a compensated peak luminance signal PK'

To this end, the peak brightness processor 150 receives the modulated video signal DATA 'for local dimming operation and receives a peak luminance signal PK for at least one of the plurality of divided logical blocks A block position calculating section 154 for generating a position signal BLK by calculating the position of a block corresponding to the peak luminance signal PK on the screen, And a peak luminance adjusting unit 156 for compensating for the peak luminance signal corresponding to the peak luminance signal.

The dimming control unit 170 receives the dimming signal DIM generated by the dimming determining unit 120 and the compensated peak brightness signal PK 'supplied from the peak brightness processing unit PK' ) To generate a compensated dimming signal DIM ', and supplies it to a backlight driver (80 in FIG. 2).

According to the above-described structure, the dimming control circuit of the present invention generates a dimming signal and a peak luminance signal through an input video signal, adjusts the peak luminance signal according to the position of the block, and then adjusts the generated dimming signal, And supplies it to the driver. Hereinafter, an example of a peak luminance compensation mode of a liquid crystal display according to a preferred embodiment of the present invention will be described with reference to the drawings.

FIG. 4A is a diagram illustrating an example of dividing a screen of a liquid crystal display according to an exemplary embodiment of the present invention into predetermined logical blocks, and FIG. 4B is a view illustrating a degree of compensation of a peak luminance value according to the position of each block .

4A shows a screen of a liquid crystal display divided into a total of 36 logical blocks as an example of dividing a screen of a liquid crystal display into 6 x 6 blocks (BLK [x, y], x, y are natural numbers) have.

According to the embodiment of the present invention, the peak luminance of the central area of the blocked liquid crystal display screen, that is, BLK [3,3], BLK [3,4], BLK [4,3], BLK [ At the same time, the initially set peak luminance value is maintained at 100%, and the peripheral area surrounding the central area, that is, BLK [1,1], BLK [2,2] . Here, the ratio of each block to the peak luminance value is not limited to a specific value, and at least the blocks of the outer region need to be applied with smaller peak luminance values than the blocks of the central region.

This is based on the fact that the higher the brightness in the central area of the screen, the more the contrast ratio becomes more noticeable and the more the color becomes lighter.

4B, in the liquid crystal display of the present invention, the peak luminance value of the central region 1A is set to 100%, and then the first outer region 2A is set to 70% to 80% By adjusting the peak luminance value of each block by setting the outer region 3A to 30% to 40%, the peak luminance value is differently applied according to the position of the block on the screen, thereby improving the contrast ratio.

5 is a diagram schematically showing luminance distribution and inter-block luminance deviation on a screen of a liquid crystal display according to the dimming control method of the present invention.

Comparing with FIG. 1B, which is an example of peak luminance compensation, the luminance of the block corresponding to the V row is driven by the high luminance of 100% or more with respect to a specific block in the conventional peak luminance driving, (C) of a liquid crystal display device driven by a peak luminance value of 100% or more is applied to the central region and a block adjacent to the central region is driven by a luminance with a gradually increasingly lower peak luminance value . As a result, the number of blocks driven at a peak luminance of 100% or more becomes smaller than that in the conventional peak luminance driving, thereby reducing the total power consumption of the liquid crystal display device. Also, as all the blocks driven at the peak luminance operate at different luminance, the gradation aggregation phenomenon is also improved.

Hereinafter, a dimming control method of a liquid crystal display according to a preferred embodiment of the present invention will be described with reference to the drawings.

6 is a diagram illustrating a dimming control method of a liquid crystal display according to a preferred embodiment of the present invention. Hereinafter, for the sake of clarity, reference will be made to the reference numerals of FIG. 3 together.

6, the dimming control method of the liquid crystal display of the present invention includes a data receiving step S600, a dimming value determination and data modulation step S610, a peak luminance value determination step S620, (S630), a peak luminance value adjustment step (S640), and a dimming value compensation step (S650).

More specifically, the data reception step S600 is a step in which the image analysis unit 110 of the dimming control circuit receives the video signal DATA from the timing controller.

In the dimming value determination and data modulation step S610, the image analysis unit 110 divides the screen of the liquid crystal display panel into a plurality of virtual logical block units divided into a matrix in correspondence with the input video signal DATA, Each block is analyzed to calculate a local dimming driving brightness value for each block to generate a dimming signal.

The data modulator 130 of the dimming control circuit compares the amount of light at the time of driving by local dimming with the amount of light at the time of normal driving with respect to the inputted video signal DATA, DATA ').

The peak luminance value determination step S620 is a step in which the peak luminance determination unit 152 receives the video signal DATA 'modulated in the step S610 and outputs a peak luminance signal PK ).

The block position calculating step S630 is a step in which the block position calculating unit 154 generates a position signal BLK which is obtained by calculating the position of a block corresponding to the peak luminance signal PK on the screen.

The step of adjusting the peak luminance value S640 is a step of compensating the peak luminance signal PK generated in the step S620 according to the position signal BLK generated in the step S630. Here, the position signal BLK includes a value for the separation distance of each block from the reference with reference to the center of the screen, and the degree of compensation of the peak luminance signal is set to be small as the separation distance is large. That is, the peak luminance value of the blocks in the central area is adjusted to be larger than the peak luminance value of the blocks in the outer area.

The dimming value compensating step S650 is a step in which the dimming control unit 170 applies the compensated dimming signal DIM 'by applying the compensated peak luminance signal PK' in step S640 to the dimming signal DIM generated in step S610, .

According to the above-described steps, the dimming control method of the present invention generates a dimming signal and a peak luminance signal through an input video signal, adjusts a peak luminance signal according to the position of the block, and adjusts the dimming signal through the peak luminance signal, The contrast ratio is improved and the power consumption is reduced.

While a great many are described in the foregoing description, it should be construed as an example of preferred embodiments rather than limiting the scope of the invention. Accordingly, the invention is not to be determined by the embodiments described, but should be determined by equivalents to the claims and the appended claims.

10: liquid crystal panel 25: external system
30: timing controller 50: gate driver
60: Data driver 70: Dimming control circuit
80: Backlight driver 90: Backlight
95: optical member

Claims (10)

A peak luminance (luminance) control circuit which receives a modulated video signal for local dimming driving and controls at least one of the logical blocks dividing the screen into a plurality of blocks so as to have a luminance value larger than that in full- A peak luminance determination unit for generating a peak luminance signal;
A block position calculation unit for analyzing the modulated video signal and generating a position signal that calculates the position of each block on the screen; And
A peak luminance adjusting unit for applying a peak luminance value of 100% or more to a block adjacent to the central region and a central region corresponding to the position signal and compensating for the peak luminance signal by applying an increasingly lower peak luminance value toward the outer periphery The dimming control circuit comprising. delete delete 1. A local dimming type liquid crystal display device for driving a backlight with different brightness between logical blocks obtained by dividing a screen into a plurality of blocks,
A liquid crystal panel;
A gate and a data driver for driving the liquid crystal panel;
A timing controller for generating control signals of the gate and the data driver, receiving and receiving image signals from an external system, and arranging and converting the signals;
A peak luminance that controls at least one of the blocks to have a luminance value larger than that in a full-white driving state in which the entire backlight lamp is lighted, modulates the video signal to correspond to the block, ) Signal and a dimming signal, and a peak luminance value of 100% or more is applied to a block adjacent to the central region and a central region according to the position of the peak luminance driving block, and a peak luminance value of a gradually lower rate is applied to the periphery A dimming control circuit that compensates the peak luminance signal and applies the dimming signal to the dimming signal;
A backlight driver for driving the backlight in response to the compensated dimming signal; And
And a backlight for providing light to the liquid crystal panel under the control of the backlight driver. delete delete delete 5. The method of claim 4,
Wherein the dimming control circuit comprises:
An image analyzer for receiving and analyzing the image signal to define a block and calculating a local dimming driving luminance value for each block;
A data modulator for aligning and modulating the image signal;
A dimming determining unit for mapping the local dimming driving brightness value to a preset dimming curve to generate the dimming signal; And
And applies a compensated peak luminance signal to the dimming signal
The liquid crystal display device further comprising: 9. The method of claim 8,
Wherein the dimming curve is implemented in the form of a look-up table (LUT). At least one of the logical blocks which receives the modulated video signal for local dimming driving and divides the screen into a plurality of blocks has a luminance value larger than that in full-white driving in which the entire backlight lamp is lit Generating a peak luminance signal for controlling a peak luminance signal;
Analyzing the modulated video signal to generate a position signal that calculates the position of each block on the screen; And
Compensating the peak luminance signal by applying a peak luminance value of 100% or more for a block adjacent to the central region and a central region corresponding to the position signal and applying a gradually lower peak luminance value toward the periphery, Dimming control method.

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