KR20090068591A - Back light unit and liquid crystal display device using the same and driving method thereof - Google Patents

Abstract

A backlight unit, a liquid crystal device using the same and a driving method thereof are provided to compensate for a property of each LED, thereby minimizing a color sense difference per an area. A dimming controller(10) generates a dimming control signal per an area according to dimming curve information per an area of a backlight and image data inputted from the outside. A backlight controller(12) generates a driving signal per an area according to the dimming curve information per each area. The backlight is divided into a plurality of areas. RGB LED modules(20,22,24) are formed in each area. The backlight emits RGBW light in response to a driving signal per each area.

Description

BACK LIGHT UNIT AND LIQUID CRYSTAL DISPLAY DEVICE USING THE SAME AND DRIVING METHOD THEREOF}

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a backlight unit, and in particular, a backlight unit that compensates for the characteristics of non-quantified LEDs and applies them to a product, thereby reducing manufacturing cost and minimizing color difference between regions. And a liquid crystal display using the same, and a driving method thereof.

As the information society develops, the demand for image display devices is increasing in various forms. Recently, liquid crystal displays, field emission displays, plasma display panels, Various flat panel displays, such as a light emitting display, are utilized.

Among them, the liquid crystal display device displays a desired image by controlling the transmission amount of light supplied from the back light unit by a liquid crystal panel having a plurality of liquid crystal cells arranged in a matrix form.

Recently, in accordance with the trend of miniaturization, thinning, and lightening of the backlight unit, a backlight unit using a light emitting diode (LED), which is advantageous in terms of power consumption, weight, and brightness, has been proposed instead of a fluorescent lamp. LEDs have high-speed response, which is effective for video signal streams and allows impulsive driving. In addition, since the luminance, color temperature, and the like can be arbitrarily changed by adjusting the amount of light of red, green, and blue LEDs, it is actively employed as a light source for a backlight unit.

Since the LED backlight unit has not been developed to emit white light until now, the LED backlight unit emits red LED, green LED, and blue LED together to generate white light. In this case, each of the red, green, and blue LEDs are different from each other, so that the LEDs are classified by each property through a separate inspection process, for example, a good quality plate, and then applied to the backlight unit.

Accordingly, the liquid crystal display device having the conventional LED backlight unit increases the manufacturing cost due to the use of LEDs for which good quality discrimination has been performed, and also applies the driving method set in accordance with the characteristics to each area. There are disadvantages such as the difference in color. Specifically, manufacturing costs increase because each LED used in the LED backlight unit is applied to the next product classified according to light emission characteristics, driving power characteristics, and luminance characteristics through a good quality discrimination process. In addition, since the backlight unit is driven at a predetermined dimming value in consideration of characteristics of each LED, color shift occurs due to external factors such as temperature change, and color difference occurs for each region. This will occur.

The present invention has been made to solve the above problems, a backlight unit that can reduce the manufacturing cost and minimize the color difference by area by compensating the characteristics of LEDs that are not performed good quality discrimination applied to products It is an object of the present invention to provide a liquid crystal display device and a driving method thereof.

According to an embodiment of the present invention, a backlight unit includes: a dimming controller configured to generate a dimming control signal for each region according to image data input from the outside and dimming curve information for each region of the backlight; A backlight controller configured to generate driving signals for each region according to the dimming control signal for each region; And the backlight, which is divided into the plurality of regions, each of the plurality of regions includes red, green, and blue LED modules and emits red, green, blue, and white light in response to a driving signal for each region. It is characterized by one.

The dimming control unit stores dimming curve information for each area in which at least one memory has the same light emission characteristics, and the gray level, brightness information, and dimming curve information for each area are input. The dimming control signal for each area is generated according to the above.

The backlight controller generates a driving signal for each region whose dimming value is changed according to the dimming control signal for each region, and a PWM memory for controlling driving timing of each of the red, green, and blue LED modules, and the red, green And a driving signal output unit for compensating and outputting each feedback signal fed back from the blue LED module to the driving signals for each region.

The backlight converts a plurality of red, green, and blue LED controllers for outputting a PWM signal, and an input voltage from an external source into a DC power source so that a duty ratio is varied according to the driving signals for each region. A plurality of DC / DC converter for generating an LED drive signal according to each of the PWM signal from the control unit is characterized in that each provided. Here, each of the red, green, and blue LED modules is characterized in that at least one red, green, or blue LED that is not tested is connected in series or in parallel.

In addition, the liquid crystal display according to an embodiment of the present invention for achieving the above object is a liquid crystal panel formed with a plurality of pixel areas; A data and gate driver for driving the liquid crystal panel; A timing controller for aligning image data from the outside with driving of the liquid crystal panel and controlling the data and the gate driver; And a backlight unit having the above-described features for receiving the aligned image data from the timing controller and irradiating light to the liquid crystal panel according to the aligned image data.

In addition, the driving method of the backlight unit according to an embodiment of the present invention for achieving the above object is to provide a dimming control signal for each area according to the image data input from the outside and dimming curve information for each area of the backlight; Generating; Generating a driving signal for each region according to the dimming control signal for each region; And emitting red, green, blue, and white light in response to the driving signal for each region.

The dimming control signal generation for each region may include storing dimming curve information for each region in which at least one memory has the same light emission characteristic as possible, and gradation and brightness information of the input image data. And generating a dimming control signal for each region according to the dimming curve information for each region.

The generating of the driving signal for each region may include generating the driving signal for each region whose dimming value is changed according to the dimming control signal for each region, red, green, and the like provided in the respective regions according to the driving signal for each region. And controlling driving timing of each of the blue LED modules, and compensating and outputting the respective feedback signals fed back from the red, green, and blue LED modules to the driving signals for each region. .

The red, green, blue and white light emission step of outputting a PWM signal so that the duty ratio (variable) ratio according to the drive signal for each area, and converts the input voltage from the outside into a DC power source The method may further include generating an LED driving signal according to a PWM signal to drive each of the red, green, and blue LED modules.

In addition, the driving method of the liquid crystal display market value according to an embodiment of the present invention for achieving the above object is a liquid crystal having a liquid crystal panel having a plurality of pixel areas and a backlight unit for irradiating light to the liquid crystal panel A method of driving a display device, the method comprising: displaying an image by adjusting light transmittance; And a method of driving the backlight unit described above to irradiate light onto the liquid crystal panel.

The backlight unit, the liquid crystal display device using the same, and a driving method thereof according to the embodiment of the present invention having the above characteristics can reduce the manufacturing cost by compensating the characteristics of LEDs for which good quality discrimination is not performed and applying them to a product. have.

In addition, by compensating and applying the characteristics of each LED to each region, the color difference of each region may be minimized to improve display quality of an image.

A backlight unit, a liquid crystal display using the same, and a driving method thereof according to an exemplary embodiment of the present invention having the above characteristics will be described in detail with reference to the accompanying drawings.

1 is a block diagram illustrating a backlight unit and a liquid crystal display using the same according to an exemplary embodiment of the present invention.

1 includes a liquid crystal panel 2 formed with a plurality of pixel regions; A data driver 4 for driving the plurality of data lines DL1 to DLm; A gate driver 6 driving a plurality of gate lines GL1 to GLn; A timing controller 8 for aligning image data RGB from the outside to be suitable for driving the liquid crystal panel 2 and controlling the data driver 4 and the gate driver 6; And a dimming control signal ADim for each region according to the image data Data arranged from the timing controller 8 and the predetermined light emission characteristics of the regions of the backlight 14, and generating dimming control signals ADim for the regions. Therefore, the backlight unit 10, 12, 14 which irradiates light to the liquid crystal panel 2 is provided.

The backlight units 10, 12, and 14 may emit image data Data arranged from the timing controller 8 and light emission characteristics of each region of the backlight 14, for example, region by region dimming curve information. A dimming control unit 10 generating a dimming control signal ADim; A backlight control unit 12 generating a driving signal CS (R, G, B) for each region according to the dimming control signal ADim for each region by using an input voltage Vin from the outside; And red (R), green (G), and blue (B) LED modules 20, 22, and 24, respectively, divided into a plurality of areas, and driving signals CS (R, G) for each area. And (B)), a backlight 14 for irradiating the liquid crystal panel 2 with red (R), green (G), blue (B) and white (W) light.

The liquid crystal panel 2 includes a thin film transistor (TFT) formed in each pixel cell defined by a plurality of gate lines GL1 to GLn and a plurality of data lines DL1 to DLm, and a liquid crystal capacitor connected to a TFT. (Clc). The liquid crystal capacitor Clc is composed of a pixel electrode connected to a TFT and a common electrode facing each other with the pixel electrode and the liquid crystal interposed therebetween. The TFT supplies the image signals from the respective data lines DL1 to DLm to the pixel electrodes in response to the scan pulses from the respective gate lines GL1 to GLn. The liquid crystal capacitor Clc charges the difference voltage between the image signal supplied to the pixel electrode and the common voltage supplied to the common electrode, and adjusts the light transmittance by varying the arrangement of liquid crystal molecules according to the difference voltage. The storage capacitor Cst is connected to the liquid crystal capacitor Clc in parallel so that the voltage charged in the liquid crystal capacitor Clc is maintained until the next data signal is supplied. The storage capacitor Cst is formed by overlapping the pixel electrode with the previous gate line and the insulating layer interposed therebetween. In contrast, the storage capacitor Cst is formed by overlapping the pixel electrode with the storage line and the insulating layer interposed therebetween.

The data driver 4 includes a data control signal DCS from the timing controller 8, for example, a source start pulse (SSP), a source shift clock (SSC), and a source output enable (SCS). The pixel data Data arranged by the timing controller 8 is converted into an analog voltage, that is, an image signal, using a source output enable (SOE) signal or the like. Specifically, the data driver 4 latches the image data (Data) input according to the SSC, and then one horizontal line every one horizontal period in which scan pulses are supplied to the gate lines GL1 to GLn in response to the SOE signal. Minute video signal is supplied to each of the data lines DL1 to DLm. At this time, the data driver 4 selects a positive or negative gamma voltage having a predetermined level according to the gray value of the pixel data Data, and supplies the selected gamma voltage to each of the data lines DL1 to DLm as an image signal. do.

The gate driver 6 sequentially generates scan pulses in response to the gate control signal GCS from the timing controller 8, for example, GSP and GSC, and pulse widths of the scan pulses according to the GOE signal from the GOE generation unit. To control. In addition, the scan pulses whose pulse width is controlled, that is, the gate-on voltages are sequentially supplied to the gate lines GL1 to GLn. Specifically, the gate driver 6 shifts the GSP from the timing controller 8 in accordance with the GSC to sequentially generate scan pulses. The pulse width of the scan pulses is controlled according to the GOE signal input from the GOE generation unit to sequentially supply the gate-on voltages having the pulse widths to the gate lines GL1 to GLn. The gate-off voltage is supplied to the gate lines GL1 to GLn during the period when the gate-on voltage is not supplied.

The timing controller 8 arranges the image data RGB input from the outside to be suitable for driving the liquid crystal panel 2 and supplies the image data RGB to the data driver 4. The data driver 4 and the gate driver 6 are controlled by generating a gate control signal GCS and a data control signal DCS using the external synchronization signals DCLK, DE, Hsync, and Vsync. . The timing controller 8 may also supply the aligned image data Data to the dimming controller 10.

FIG. 2 is a graph illustrating dimming curve information for each region stored in the dimming controller of FIG. 1. 3 is a block diagram illustrating an LED module for each region included in the backlight of FIG. 1.

The dimming control unit 10 illustrated in FIG. 2 includes at least one memory including an EEPROM, a look-up table, and the like. In this memory, dimming curve information 1MD to 4MD for each region is set such that the light emission characteristics of the regions 1Dm to nDm shown in FIG. The dimming control unit 10 generates a dimming control signal ADim for each region according to the image data Data arranged from the timing controller 8 and the dimming curve information 1MD to 4MD for each region.

Specifically, the backlight 14 illustrated in FIG. 3 is divided into a plurality of regions 1Dm to nDm, and red, green, and blue LED modules 20, 22, and 24 are respectively formed in each region 1Dm to nDm. These are each provided. At least one red, green, and blue LED (R_LED, G_LED, B_LED) is connected in series or in parallel to each of the red, green, and blue LED modules 20, 22, and 24. The red, green, and blue LEDs (R_LED, G_LED, B_LED) included in the backlight 14 of the present invention are applied to the product without the discrimination of good quality, so that the light emission characteristics of each region (1Dm to nDm) are different. Is very different. Accordingly, the light emitting characteristics of the regions 1Dm to nDm, for example, brightness characteristics, luminance characteristics, driving voltage characteristics, and the like, are detected while the liquid crystal panel 2 is not formed on the backlight 14. Then, dimming curve information 1MD to 4MD for each region 1Dm to nDm is generated according to the detected information. In other words, the dimming curve information 1MD to 4MD for each region 1Dm to nDm may be generated in the form of a field-programmable gate array (FPGA) and applied to the dimming controller 10. Here, FPGAs are integrated circuits in the form of intermediate developments that are built to finally verify the operation and performance of the hardware just before the hardware is already designed. Therefore, at least one memory included in the dimming controller 10 may be generated in the form of FPGA before the liquid crystal panel 2 is formed. As such, the dimming curve information 1MD to 4MD for each region stored in the at least one memory is data set such that the light emission characteristics of each of the regions 1Dm to nDm are the same. In addition, the dimming curve information 1MD to 4MD for each region stored in the at least one memory may be optimized white balance information for each region 1Dm to nDm.

As described above, the dimming control unit 10 is composed of an EEPROM, a look-up table, or the like, which is formed outside the backlight unit, that is, a liquid crystal display or an external video system, to back up the dimming curve information 1MD to 4MD for each region. It may be provided to the light unit. In addition, the dimming curve information 1MD to 4MD for each area may be stored in some storage areas of the Extended Display Identification Data (EDID). Here, since the EDID includes a look-up table area for storing display information and resolution information of the liquid crystal display, dimming curve information 1MD to 4MD for each area may also be stored in the EDID and provided to the backlight unit. have. However, hereinafter, only the case in which the dimming control unit 10 is formed in the backlight unit will be described for convenience of description.

Referring to FIG. 2, when the image data Data arranged in the timing controller 8 is input, the dimming control unit 10 uses the dimming curve information 1MD to 4MD of each area to control the dimming control signal ADim for each area. ) In detail, the dimming control unit 10 extracts a duty ratio to be applied to a corresponding area by comparing luminance or brightness information (Y; nit) for each gray level (G) of the input image data (Data). Afterwards, the dimming control signal ADim for each region is generated to correspond to the extracted duty ratio. Here, the dimming control unit 10 calculates an average grayscale G and luminance information Y of image data Data input from at least one horizontal line unit or at least one frame unit from the timing controller 8 to dimming each region. The control signal ADim may also be generated. For example, if the average red gradation G of one frame input from the timing controller 8 indicates 145 gradations, the brightness information of 0.8 nits may be extracted from the dimming curve information 1MD of the first region 1Dm. In this case, the duty ratio of the red LED module 20 of the first region 1Dm may be set to 80%. Further, if the average green gradation G of one frame input from the timing controller 8 indicates 145 gradations, the brightness information of 0.6 nits can be extracted from the dimming curve information 1MD of the first region 1Dm. In this case, the duty ratio of the first region 1Dm green LED module 22 may be set to 60%. In addition, if the average blue gradation G of one frame input from the timing controller 8 indicates 105 gradations, the brightness information of 0.5 nits can be extracted from the dimming curve information 1MD of the first region 1Dm. In this case, the duty ratio of the first region 1Dm blue LED module 24 may be set to 50%. As such, when the image data (Data) is input, the dimming control unit 10 generates a dimming control signal ADim whose duty ratio is converted according to the emission characteristics of each region by using dimming curve information 1MD to 4MD for each region. do. The dimming control signal ADim for each region is supplied to the backlight controller 12.

The backlight controller 12 uses the region-specific driving signals CS (R, G, and B) corresponding to the region-specific dimming control signals ADim input from the dimming controller 10 using an external input voltage Vin. ) And supplies it to the backlight 14. In addition, the backlight controller 12 transmits feedback signals fed back from each of the red, green, and blue LED modules 20, 22, and 24 to the driving signals CS (R, G, B) for each region. It can also be compensated for output.

Specifically, the backlight controller 12 generates driving signals CS (R, G, B) for each region according to the dimming control signal ADim for each region, thereby generating red, green, and blue LED modules 20, 22, The drive timing of 24 is controlled. In other words, the backlight controller 12 may include at least one memory to generate region-specific driving signals CS (R, G, and B) corresponding to the region-specific dimming control signals ADim. . In this case, the backlight controller 12 may vary the on / off time of each of the LED driving modules 20, 22, and 24 provided in the backlight 14 according to the input dimming control signal ADim for each region. You can also drive in (Burst Mode). The backlight controller 12 may back light by varying the on / off time of each LED module 20, 22, 24 or varying the voltage level of the driving signal CS (R, G, B) for each region. Adjust the brightness of (14).

The backlight 14 includes red, green, and blue LED modules 20, 22, and 24 in the plurality of areas 1Dm to nDm, and provides driving signals CS (R, G, B) for each area. And a light source driver 16 for supplying the LED driving signal to each of the red, green, and blue LED modules 20, 22, and 24 in response.

4 is a configuration diagram illustrating in detail the backlight control unit and the backlight illustrated in FIG. 1.

The backlight control unit 12 shown in FIG. 4 generates driving signals CS (R, G, B) for each region in which a dimming value is changed according to the dimming control signal ADim for each region. PWM memory 21 for controlling the driving timing of each of the green and blue LED modules 20, 22, and 24, and respective feedback signals FV fed back from the red, green, and blue LED modules 20, 22, and 24. And a drive signal output section 22 for compensating (R, G, B) to the drive signals CS (R, G, B) for each region.

The PWM memory 21 outputs the region-specific driving signals CS (R, G, B) having the dimming value changed to correspond to the input region-specific dimming control signal ADim. Here, the dimming control signal ADim for each region may be used as the driving signals CS (R, G, B) for each region. In other words, when the PWM memory 21 is not formed, the dimming control signal ADim may be directly supplied to the driving signal output unit 22 as the region-specific driving signals CS (R, G, B).

The driving signal output unit 22 supplies the respective feedback signals FV (R, G, B) fed back from the red, green, and blue LED modules 20, 22, and 24 to the driving signals CS (R) for each region. , G, B)) to compensate for the output. To this end, the drive signal output unit 22 may be further provided with a DC / DC converter, a buffer and an amplifier circuit. The driving signal output unit 22 may vary the on / off times of the LED modules 20, 22, and 24, or may vary the voltage levels of the driving signals CS (R, G, B) for each region. The brightness of the backlight 14 may be adjusted.

The light source driver 16 generates a PWM signal in response to the drive signals CS (R, G, B) of each region, and also converts an input voltage Vin from the outside into a DC power source DC. do. The LED driving signal is generated by controlling the output timing of the DC power supply DC according to each PWM signal, thereby controlling the driving timing of each of the red, green, and blue LED modules 20, 22, and 24, respectively.

Since the light source driver 16 outputs the PWM signal for each region in response to the drive signals CS (R, G, B) for each region, the light source driver 16 corresponds to each of the red, green, and blue LED modules 20, 22, and 24. The light source driver 16R may be classified into a plurality of red light source drivers 16R, green light source drivers 16G, and blue light source drivers 16B.

Each of the plurality of red, green, and blue light source drivers 16R, 16G, and 16B has a duty ratio, that is, a high section ratio in one period, according to the driving signals CS (R, G, B) for each region. The red, green, and blue LED controllers 31, 33, and 35, which output PWM signals so as to be variable, and the input voltage Vin from the outside are converted into a DC power source, and the respective LED controllers 31, 33, and 35 are converted to DC power. DC / DC converters 32, 34 and 36 which generate LED driving signals in accordance with PWM signals from the < RTI ID = 0.0 >

Each of the plurality of red, green, and blue LED controllers 31, 33, and 35 may vary the duty ratio of the PWM signal according to the pulse width of the driving signal CS (R, G, B) for each region, The amplitude of the PWM signal may also be varied according to the amplitude of the star driving signals CS (R, G, B). In other words, each of the LED controllers 31, 33, 35 varies the amplitude and pulse width of the PWM signal according to the amplitude and pulse width of the driving signals CS (R, G, B) for each region, thereby changing each LED module ( The driving timing of the 20, 22, and 24 may be controlled, and the brightness of each LED (R, G, B_LED) may also be controlled. Each of the plurality of red, green, and blue LED controllers 31, 33, and 35 may further include a driving signal generator, a switching unit, a transformer, and the like, which are not shown.

On the other hand, the backlight 14 of the present invention is disposed on the plurality of LED modules 20, 22, 24 in addition to the light source driver 16 to improve the brightness and efficiency of the light from the LED array to irradiate the liquid crystal panel 2 It may be provided with a plurality of optical sheets (not shown). Here, each of the plurality of LED modules 20, 22, and 24 may be disposed in a matrix form on a printed circuit board so that light is uniformly radiated onto the entire rear surface of the liquid crystal panel 2. In addition, the plurality of optical sheets include at least one diffusion sheet (or diffuser plate) for diffusing light incident from the plurality of LED modules 20, 22, and 24, and the light diffused by the diffusion sheet includes the liquid crystal panel 2. At least one prism sheet for converting the path of the light to proceed toward it to improve the efficiency of the light.

On the other hand, the backlight 14 of the present invention is such that the plurality of LED modules 20, 22, 24 arranged in a horizontal position on the side of the backlight 14 to the front of the liquid crystal panel 2 through the light guide plate. It may be an edge-type backlight system that allows this to be irradiated.

The present invention described above is not limited to the above-described embodiment and the accompanying drawings, and it is common in the art that various substitutions, modifications, and changes can be made without departing from the technical spirit of the present invention. It will be evident to those who have knowledge of.

1 is a block diagram showing a backlight unit and a liquid crystal display using the same according to an embodiment of the present invention.

FIG. 2 is a graph illustrating dimming curve information for each region stored in the dimming controller of FIG. 1. FIG.

3 is a block diagram showing an LED module for each area provided in the backlight of FIG.

4 is a configuration diagram illustrating in detail the backlight control unit and the backlight illustrated in FIG. 1;

* Brief description of symbols for the main parts of the drawings.

2: LCD panel 4: data driver

6: gate driver 8: timing controller

10: dimming control unit 12: backlight control unit

14: backlight 16: light source drive unit

20: red LED module 21: PWM memory

22: green LED module 23: drive signal output unit

24: blue LED module 31: red LED control unit

33: green LED control unit 35: blue LED control unit

32, 34, 36: DC / DC converter

Claims (11)

A dimming controller configured to generate a dimming control signal for each region according to image data input from the outside and dimming curve information for each region of the backlight; A backlight controller configured to generate driving signals for each region according to the dimming control signal for each region; And The backlight device is divided into a plurality of areas and includes red, green, and blue LED modules in each of the plurality of areas and emits red, green, blue, and white light in response to a driving signal for each area. Back light unit, characterized in that. The method of claim 1, The dimming control unit Storing dimming curve information for each region in which at least one memory has the same light emission characteristic, and storing the dimming curve information for each region according to gray level, brightness information, and dimming curve information for each region. And a dimming control signal for each region. The method of claim 2, The backlight control unit A PWM memory for generating driving signals for each region whose dimming values are changed according to the dimming control signals for each region to control driving timing of each of the red, green, and blue LED modules; And a driving signal output unit for compensating and outputting respective feedback signals fed back from the red, green, and blue LED modules to the driving signals for each region. The method of claim 3, wherein The back light A plurality of red, green, and blue LED controllers for outputting a PWM signal such that a duty ratio is varied according to the driving signals for each region; And a plurality of DC / DC converters, each of which converts an input voltage from an external source into a DC power source and generates an LED driving signal according to each of the PWM signals from the respective LED controllers. The method of claim 4, wherein Each of the red, green, and blue LED modules At least one red, green, or blue LED in which the inspection process has not been performed is connected in series or in parallel. A liquid crystal panel formed with a plurality of pixel regions; A data and gate driver for driving the liquid crystal panel; A timing controller for aligning image data from the outside with driving of the liquid crystal panel and controlling the data and the gate driver; And And a backlight unit according to any one of claims 1 to 5, for receiving the aligned image data from the timing controller and irradiating light to the liquid crystal panel according to the aligned image data. Display. Generating a dimming control signal for each region according to image data input from the outside and dimming curve information for each region of the backlight; Generating a driving signal for each region according to the dimming control signal for each region; And And emitting red, green, blue, and white light in response to the driving signal for each region. The method of claim 7, wherein The dimming control signal generation step for each area Storing dimming curve information for each of the regions, wherein the dimming curve information for each of the regions is set in at least one memory so that the light emission characteristics of the regions are as equal as possible; and And generating a dimming control signal for each region according to the gradation, brightness information, and dimming curve information for each region of the input image data. The method of claim 8, The driving signal generation step for each area is Generating a driving signal for each region whose dimming value is changed according to the dimming control signal for each region; Controlling driving timing of each of the red, green, and blue LED modules included in each of the regions according to the driving signal of each region; and And compensating for each of the feedback signals fed back from the red, green, and blue LED modules to the driving signals for each region, and outputting the feedback signals. The method of claim 9, The light emitting step of the red, green, blue and white light Outputting a PWM signal so that a duty ratio is varied according to the driving signal for each region, and And converting an input voltage from an external source into a direct current power source and generating an LED driving signal according to each of the PWM signals to drive each of the red, green, and blue LED modules. In the driving method of a liquid crystal display device comprising a liquid crystal panel having a plurality of pixel areas and a backlight unit for irradiating light to the liquid crystal panel, Displaying an image by adjusting the transmittance of light; And 11. A method of driving a liquid crystal display device, comprising the driving method of any one of claims 7 to 10 to irradiate light onto the liquid crystal panel.

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