KR101275908B1 - LCD and drive method thereof - Google Patents

Abstract

The present invention provides a liquid crystal display device that can calculate white data supplied from each subframe of one frame while maintaining R, G, C, and B colors, and includes an input consisting of first and second subframes. A data converter for converting RGB data of the frame into RGCB data; A gain calculator for calculating a first gain of RC data of the first subframe and a second gain of GB data of the second subframe; A data amplifier for amplifying the gray value of the RC data of the first subframe in proportion to the first gain and amplifying the gray value of the GB data of the second subframe in proportion to the second gain; A gray scale calculator for calculating a first minimum gray value in the RC data of the amplified first subframe and calculating a second minimum gray value in the GB data of the amplified second subframe; And calculating the RC data and W first data to be supplied in the first subframe using the first and second gains and the first and second minimum gray values, and the GB data and W to be supplied in the second subframe. And a data calculator for calculating and outputting the data.

LCD, White Data, Frame, Color, Light

Description

Liquid crystal display and driving method thereof

1 is an equivalent circuit diagram of a pixel formed in a general liquid crystal display device.

2 is a configuration diagram of a general liquid crystal display device.

3 is a block diagram of a liquid crystal display according to an exemplary embodiment of the present invention.

4 is a configuration diagram of a data processor in FIG. 3.

5A to 5G are exemplary diagrams for describing an operation process of the data processor of FIG. 3.

Description of the Related Art

100, 200: liquid crystal display device 110, 210: liquid crystal display panel

120, 240: data driver 130: gate driver

140: gamma reference voltage generator 150, 250: backlight assembly

160: inverter 170: common voltage generator

180: Gate driving voltage generator 190, 230: Timing controller

220: data processor 221: data conversion unit

222: gain calculator 223: data amplifier

224: gradation calculator 225: data calculator

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a liquid crystal display device, and more particularly, to a liquid crystal display device and a driving method thereof capable of calculating white data supplied from each subframe of one frame while maintaining R, G, C, and B colors. .

A liquid crystal display device displays an image by adjusting light transmittance of liquid crystal cells according to a video signal, and an active matrix type liquid crystal display device in which a switching element is formed for each liquid crystal cell enables active control of the switching element. This is advantageous for video implementation. As the switching element used in the active matrix liquid crystal display device, a thin film transistor (hereinafter referred to as TFT) is mainly used as shown in FIG. 1.

Referring to FIG. 1, an active matrix type liquid crystal display converts digital input data into an analog data voltage based on a gamma reference voltage and supplies it to the data line DL and simultaneously supplies scan pulses to the gate line GL. The liquid crystal cell Clc is charged.

The gate electrode of the TFT is connected to the gate line GL, the source electrode is connected to the data line DL, and the drain electrode of the TFT is a pixel electrode of the liquid crystal cell Clc and one electrode of the storage capacitor Cst. Is connected to.

A common voltage Vcom is supplied to the common electrode of the liquid crystal cell Clc.

The storage capacitor Cst serves to charge the data voltage applied from the data line DL when the TFT is turned on to maintain the voltage of the liquid crystal cell Clc constant.

When a scan pulse is applied to the gate line GL, the TFT is turned on to form a channel between the source electrode and the drain electrode to apply a voltage on the data line DL to the pixel electrode of the liquid crystal cell Clc Supply. At this time, the liquid crystal molecules of the liquid crystal cell Clc modulate the incident light by changing the arrangement by the electric field between the pixel electrode and the common electrode.

A configuration of a general liquid crystal display device having pixels having such a structure will be described with reference to FIG. 2. However, among the abbreviations written below, R is Red, G is Green, B Blue, C is Cyan, W is White, And M is magenta.

2 is a configuration diagram of a general liquid crystal display device.

Referring to FIG. 2, the liquid crystal display device 100 includes a thin film transistor for driving the liquid crystal cell Clc at the intersection of the data lines DL1 to DLm and the gate lines GL1 to GLn. TFT: a thin film transistor (110) having a thin film transistor (110), a data driver (120) for supplying data to the data lines (DL1 to DLm) of the liquid crystal display panel 110, the liquid crystal display panel 110 A gate driver 130 for supplying scan pulses to the gate lines GL1 to GLn of the gate line, a gamma reference voltage generator 140 for generating a gamma reference voltage and supplying the gamma reference voltage to the data driver 120, and a liquid crystal display A backlight assembly 150 for irradiating light to the panel 110, an inverter 160 for applying an alternating voltage and current to the backlight assembly 150, and a common voltage Vcom are generated to generate a liquid crystal display panel ( The common voltage generator 170 to supply the common electrode of the liquid crystal cell Clc of 110. Controlling the gate driver voltage generator 180, the data driver 120, and the gate driver 130 to generate and supply the gate high voltage VGH and the gate low voltage VGL to the gate driver 130. A timing controller 190 is provided.

In the liquid crystal display panel 110, liquid crystal is injected between two glass substrates. On the lower glass substrate of the liquid crystal display panel 110, the data lines DL1 to DLm and the gate lines GL1 to GLn are orthogonal. TFTs are formed at intersections of the data lines DL1 to DLm and the gate lines GL1 to GLn. The TFT supplies the data on the data lines DL1 to DLm to the liquid crystal cell Clc in response to the scan pulse. The gate electrodes of the TFTs are connected to the gate lines GL1 to GLn, and the source electrodes of the TFTs are connected to the data lines DL1 to DLm. The drain electrode of the TFT is connected to the pixel electrode of the liquid crystal cell Clc and the storage capacitor Cst.

The TFT is turned on in response to the scan pulse supplied to the gate terminal via the gate lines GL1 to GLn. When the TFT is turned on, video data on the data lines DL1 to DLm is supplied to the pixel electrode of the liquid crystal cell Clc.

The data driver 120 supplies data to the data lines DL1 to DLm in response to the data driving control signal DDC supplied from the timing controller 190, and digital video data supplied from the timing controller 190. (RGB) is sampled and latched, and then converted into an analog data voltage capable of expressing gray scales in the liquid crystal cell Clc of the liquid crystal display panel 110 based on the gamma reference voltage supplied from the gamma reference voltage generator 140. Supply to the data lines DL1 to DLm.

The gate driver 130 sequentially generates scan pulses, that is, gate pulses, in response to the gate driving control signal GDC and the gate shift clock GSC supplied from the timing controller 190, thereby providing the gate lines GL1 to GLn. To feed. The gate driver 130 determines the high level voltage and the low level voltage of the scan pulse in accordance with the gate high voltage VGH and the gate low voltage VGL supplied from the gate drive voltage generator 180, respectively.

The gamma reference voltage generator 140 receives a high potential power supply voltage VDD to generate a positive gamma reference voltage and a negative gamma reference voltage and output the same to the data driver 120.

The backlight assembly 150 is disposed on the rear surface of the liquid crystal display panel 110 and emits light by an AC voltage and a current supplied from the inverter 160 to irradiate light to each pixel of the liquid crystal display panel 110.

The inverter 160 converts the square wave signal generated therein into a triangular wave signal and compares the triangular wave signal with a DC power supply voltage (VCC) supplied from the system to generate a burst dimming signal proportional to the comparison result. . When a burst dimming signal determined according to an internal square wave signal is generated, a driving IC (not shown) for controlling the generation of AC voltage and current in the inverter 160 is supplied to the backlight assembly 150 according to the burst dimming signal. Control the generation of alternating voltage and current.

The common voltage generator 170 receives the high potential power voltage VDD to generate the common voltage Vcom and supplies the common voltage Vcom to the common electrodes of the liquid crystal cells Clc of each pixel of the liquid crystal display panel 110.

The gate driving voltage generator 180 receives the high potential power voltage VDD to generate the gate high voltage VGH and the gate low voltage VGL to supply the gate driver 130 to the gate driver 130. Here, the gate driving voltage generation unit 180 generates a gate high voltage VGH that is greater than or equal to the threshold voltage of the TFTs provided in each pixel of the liquid crystal display panel 110, and the gate low voltage that is less than or equal to the threshold voltage of the TFT. VGL). The gate high voltage VGH and the gate low voltage VGL generated in this way are used to determine the high level voltage and the low level voltage of the scan pulse generated by the gate driver 130, respectively.

The timing controller 190 supplies digital video data RGB, which is supplied from an image processing scaler (not shown) included in a system such as a television receiver or a computer monitor, to the data driver 120, and also provides a clock signal CLK. The data driving control signal DDC and the gate driving control signal GDC are generated using the horizontal / vertical synchronizing signals H and V and supplied to the data driver 120 and the gate driver 130, respectively. The data driving control signal DDC includes a source shift clock SSC, a source start pulse SSP, a polarity control signal POL, a source output enable signal SOE, and a gate driving control signal GDC. ) Includes a gate start pulse (GSP) and a gate output enable (GOE).

The liquid crystal display device having such a configuration and function is implemented by various driving methods according to the color filter and the backlight light source applied to the liquid crystal display panel 110.

First, the liquid crystal display device 100 to which the RGB color filter is applied has the following driving method.

Since the R subpixels, the G subpixels, and the B subpixels spatially divided by the RGB color filters formed in the liquid crystal display panel 110 constitute one pixel, the liquid crystal display device 100 includes a white lamp that generates only white light. Used as a light source for backlight. Thus, the white light irradiated from the white lamp is spatially divided and irradiated to the R, G and B subpixels, and only 30% of the irradiated light is transmitted through the RGB color filter.

Second, the liquid crystal display device 100 to which the color filter is not applied has the following sequential driving (FS) method.

In the liquid crystal display device 100 to which the FS driving method is applied, a plurality of RGB pixels having no spatially divided subpixels are formed on the liquid crystal display panel 110 and a color filter is not applied. R light sources, G light sources and B light sources that generate R light, G light and B light, respectively, are used as backlights. Since each RGB pixel does not have a spatially divided subpixel, the RGB color is displayed by dividing and irradiating the R light, the G light, and the B light in time. Since the color filter is not used in the FS drive type liquid crystal display device 100, the transmittance of the R light, the G light and the B light reaches 100%, and the aperture ratio can be increased as compared with the use of the color filter.

Third, the liquid crystal display device 100 to which the GM color filter is applied has the following driving method.

Since the G subpixels and the M subpixels spatially divided by the GM color filter formed in the liquid crystal display panel 110 constitute one pixel, the liquid crystal display device 100 generates C and Y light, respectively. A light source and a Y light source are used as the backlight. In the liquid crystal display 100, a frame is driven at a driving frequency of 60 Hz, and the frame is composed of first and second subframes driven at a driving frequency of 120 Hz.

In the state where the first subframe is driven at the 120 Hz driving frequency, the liquid crystal display 100 supplies C data and B data to the G subpixel and the M subpixel, respectively, and simultaneously irradiates the C light. At this time, 50% of the irradiated light amount is transmitted through the GM color filter.

In the state where the second subframe is driven at the 120 Hz driving frequency, the liquid crystal display 100 supplies G data and R data to the G subpixel and the M subpixel, respectively, and simultaneously irradiates the Y light. At this time, 50% of the irradiated light amount is transmitted through the GM color filter.

The liquid crystal display device employing such a driving method uses fewer color filters than the RGB color filter, so that the transmittance and aperture ratio are improved. In addition, in a liquid crystal display device using an RGB color filter, one frame is composed of three subframes driven at a driving frequency of 180 Hz, whereas in a liquid crystal display device using a GM color filter, one frame is driven at a driving frequency of 120 Hz. Since two subframes are driven, the driving frequency of the subframe is reduced.

However, the liquid crystal display device to which the GM color filter is applied has a disadvantage in that each pixel on the liquid crystal display panel has to be designed in two subpixel structures as compared to the liquid crystal display device to which the color filter is not applied.

In order to alleviate this disadvantage, three subpixel structures are used as they are without redesigning the pixel structure by forming spatially divided G subpixels, W subpixels, and M subpixels within each pixel formed in the liquid crystal display panel. In addition, a technique for improving transmittance and aperture ratio by dividing and irradiating C light and Y light in time has been proposed. In this improved technology, white data (W data) must be calculated from RGB data input from a system. However, there is still a problem that R, G, C, and B colors are modulated due to W data calculation.

The present invention has been made to solve the above problems, an object of the present invention is to provide a liquid crystal that can calculate the white data supplied from each subframe of one frame while maintaining the colors of R, G, C and B as it is A display device and a driving method thereof are provided.

An object of the present invention is to calculate the white data supplied in each subframe of one frame while maintaining the colors of R, G, C, and B, thereby increasing the white luminance and increasing the cyan and yellow luminance in each subframe. A liquid crystal display device and a driving method thereof are provided.

The present invention for achieving the above object, the data conversion unit for converting the RGB data of the input frame consisting of the first and second sub-frame to the RGCB data; A gain calculator for calculating a first gain of RC first data of the first subframe among the converted RGCB data and calculating a second gain of GB first data of the second subframe; Amplifying the gradation value of RC first data of the first subframe in proportion to the calculated first gain and amplifying the gradation value of GB first data of the second subframe in proportion to the calculated second gain A data amplifier for; A gray scale calculator for calculating a first minimum gray scale value in RC second data of the amplified first subframe and a second minimum gray scale value among GB second data of the amplified second subframe; And calculating the RC third data and the W first data of the first subframe by using the calculated first and second gains and the first and second minimum gray values. And a data calculator for calculating and outputting the third data and the W second data.

According to the present invention, a plurality of data lines and a plurality of gate lines intersect each other, and pixels are formed at intersections thereof, and G subpixels, W subpixels, and M subpixels are formed at the intersections of the data lines and the gate lines. A liquid crystal display panel; After converting RGB data of an input frame consisting of first and second subframes into RGCB data and generating W first and second data to be supplied in the first and second subframes using the RGCB data, A data processor for outputting RC data and W first data of a first subframe and outputting GB data and W second data of the second subframe; A timing controller for controlling supply timing of RC data and W first data of the first subframe and GB data and W second data of the second subframe; Under the control of the timing controller, the liquid crystal is converted by converting RC data and W first data of the first subframe and GB data and W second data of the second subframe into analog data. A data driver for supplying the display panel; And a backlight assembly for sequentially irradiating the C light and the Y light to the liquid crystal display panel.

The data processor includes a data converter for converting RGB data of the input frame into RGCB data; A gain calculator for calculating a first gain of RC first data of the first subframe among the converted RGCB data and calculating a second gain of GB first data of the second subframe; Amplifying the gradation value of RC first data of the first subframe in proportion to the calculated first gain and amplifying the gradation value of GB first data of the second subframe in proportion to the calculated second gain A data amplifier for; A gray scale calculator for calculating a first minimum gray scale value in RC second data of the amplified first subframe and a second minimum gray scale value among GB second data of the amplified second subframe; And calculating the RC third data and the W first data of the first subframe by using the calculated first and second gains and the first and second minimum gray values. And a data calculator for calculating and outputting the third data and the W second data.

The gain calculator may calculate a first highest gray value and a third minimum gray value of the RC first data of the first subframe.

The gain calculator may divide the sum of the first highest gray value and the third minimum gray value into the first highest gray value and calculate a quotient of the first gain.

The gain calculating unit may calculate a second highest gray level value and a fourth minimum gray level value of the GB first data of the second subframe.

The gain calculator may divide the sum of the second highest gray value and the fourth lowest gray value by the second highest gray value and calculate a quotient of the second gain.

The data amplifier may amplify the gray value of the RC first data by multiplying the gray value of the RC first data of the first subframe by the first gain.

The data amplifier may amplify the gray value of the GB first data by multiplying the gray value of the GB first data of the second subframe by the second gain.

The data calculator may calculate the RC third data by subtracting the first minimum gray value from the gray value of the RC second data of the amplified first subframe.

The data calculator may calculate the GB third data by subtracting the second minimum gray value from the gray value of the GB second data of the amplified second subframe.

When the RC data and the W first data of the first subframe are input, the data driver supplies analog R data and C data to the M subpixel and the G subpixel, respectively, and supplies analog W first data to the W subpixel. It is characterized by the supply.

The backlight assembly may be configured to irradiate the C light to the liquid crystal display panel when the first subframe is driven.

When the GB data and the W second data of the second subframe are input, the data driver supplies analog G data and B data to the G subpixel and M subpixel, respectively, and supplies analog W second data to the W subpixel. It is characterized by the supply.

The backlight assembly may be configured to irradiate the Y light to the liquid crystal display panel when the second subframe is driven.

The present invention includes converting RGB data of an input frame consisting of first and second subframes into RGCB data; Calculating a first gain of RC first data of the first subframe among the converted RGCB data and calculating a second gain of GB first data of the second subframe; Amplifying the gray value of the RC first data of the first subframe in proportion to the calculated first gain and amplifying the gray value of the GB first data of the second subframe in proportion to the calculated second gain step; Calculating a first minimum gray scale value among the RC second data of the amplified first subframe and calculating a second minimum gray scale value among the GB second data of the amplified second subframe; And calculating the RC third data and the W first data of the first subframe by using the calculated first and second gains and the first and second minimum gray values. Calculating 3 data and W second data.

Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings.

3 is a block diagram of a liquid crystal display according to an exemplary embodiment of the present invention.

Referring to FIG. 3, the liquid crystal display device 200 according to the present invention may include the gate driver 130, the gamma reference voltage generator 140, and the inverter 160 in the same manner as the liquid crystal display device 100 shown in FIG. 1. ), A common voltage generator 170, and a gate driving voltage generator 180.

In the liquid crystal display device 200 of the present invention, the data lines DL1 to DLm and the gate lines GL1 to GLn cross each other, and pixels are formed in the intersections thereof. The subpixel and the M subpixel are formed at the intersection of the data line and the gate line, and the three primary color RGB data of the input frame are converted into four primary color RGCB data and input using the four primary color RGCB data. After generating W first and second data to be supplied in the first and second subframes of the frame, the RC data and W first data of the first subframe are output and the GB data and W second of the second subframe are output. A data processor 220 for outputting data and controlling the timing of supplying the RC data and W data of the first subframe output from the data processor 220 and the GB data and W second data of the first and second subframes; Tie for Under the control of the controller 230 and the timing controller 230, RC data and W first data of the first subframe input through the timing controller 230 and GB data and W second data of the second subframe. Is supplied to the G subpixels, W subpixels, and M subpixels of the pixels formed on the liquid crystal display panel 210, and C light and Y light are sequentially supplied to the liquid crystal display panel 210. And a backlight assembly 250 for illumination. However, one frame input from the system is driven at a driving frequency of 60 Hz, and the frame is composed of first and second subframes driven at a driving frequency of 120 Hz.

The liquid crystal display panel 110 has an upper glass substrate and a lower glass substrate that are symmetrically overlapped with each other, and liquid crystal is injected between the upper and lower glass substrates. Here, the data lines DL1 to DLm and the gate lines GL1 to GLn are orthogonal to each other on the lower glass substrate, and pixels are formed in the intersections thereof, and G subpixels, W subpixels, and M are formed in each pixel. Subpixels are formed at the intersections of the data lines and the gate lines. Here, the G subpixel, the W subpixel, and the M subpixel are formed by the GWM color filter formed on the liquid crystal display panel 210 and are spatially divided. TFTs are formed in the G subpixels, the W subpixels, and the M subpixels, and the TFTs transmit data on the data lines DL1 to DLm to the liquid crystal cell Clc in response to a scan pulse from the gate driver 130. Will be supplied.

The data processor 220 converts the three primary color RGB data of the frame input from the system into the four primary color RGCB data and calculates a gain from the converted four primary color RGCB data. The data processor 220 amplifies the gray value of the RC data of the first subframe and the GB value of the GB data of the second subframe in proportion to the calculated gain, and then performs the minimum gray scale among the RC data of the amplified first subframe. A value is calculated and a minimum gray value is calculated among the GB data of the amplified second subframe. The data processor 220 calculates RC data and W first data to be supplied in the first subframe using the calculated gains and minimum gray values, and converts GB data and W second data to be supplied in the second subframe. The output is output to the timing controller 230.

The timing controller 230 transmits the digital RC data and W first data of the first subframe and the digital GB data and W second data of the second subframe to the data driver 240 sequentially output from the data processor 220. At the same time, the data drive control signal DDC and the gate drive control signal GDC are generated by using the horizontal / vertical synchronization signals H and V from the system according to the clock signal CLK input from the system. The data driver 240 and the gate driver 130 are respectively supplied. The data driving control signal DDC includes a source shift clock SSC, a source start pulse SSP, a polarity control signal POL, a source output enable signal SOE, and a gate driving control signal GDC. ) Includes a gate start pulse (GSP) and a gate output enable (GOE).

The data driver 240 controls the digital RC data and W first data of the first subframe and the digital GB data of the second subframe and the W second inputted through the timing controller 230 under the control of the timing controller 230. The data is converted into analog data and supplied to the liquid crystal display panel 210 as follows.

When the digital RC data and the W first data of the first subframe are input through the timing controller 230, the data driver 240 converts the digital RC data and the W first data into analog data, and then the M subpixel and the M subpixel. The analog R data and the C data are supplied to the G subpixels, respectively, and the analog W first data is supplied to the W subpixels.

When the digital GB data and the W second data of the second subframe are input through the timing controller 230, the data driver 240 converts the digital GB data and the W second data into analog data, and then the G subpixel and the second subframe. The analog G data and the B data are supplied to the M subpixels, respectively, and the analog W second data is supplied to the W subpixels.

The backlight assembly 250 emits light by the driving voltage and the current supplied from the inverter 160 to irradiate the C light and the Y light to the liquid crystal display panel 210 in the following order.

When the first subframe is driven, the analog R data and the C data are supplied to the M subpixel and the G subpixel, respectively, and the analog W first data is supplied to the W subpixel, and then the backlight assembly 250 supplies the C light. The liquid crystal display panel 210 is irradiated.

When the second subframe is driven, after the analog G data and the B data are supplied to the G subpixel and the M subpixel, respectively, and the analog W second data is supplied to the W subpixel, the backlight assembly 250 emits Y light. The liquid crystal display panel 210 is irradiated.

4 is a configuration diagram of the data processor of FIG. 3.

As shown in FIG. 4, the data processor 220 includes a data converter 221 for converting three primary color RGB data of a frame input from a system into four primary color RGCB data, and the converted four primary color RGCB data. A gain calculator 222 for calculating a first gain of RC data of the first subframe and a second gain of GB data of the second subframe among the first subframes and a first subframe in proportion to the calculated first gain A data amplifying unit 223 for amplifying the gray level value of the RC data of the second subframe and amplifying the gray level value of the GB data of the second subframe in proportion to the calculated second gain; A gray level calculator 224 for calculating a gray value and calculating a minimum gray value among the GB data of the amplified second subframe, and using the calculated first and second gains and minimum gray values in the first subframe. RC to be supplied And a data and a first data W data calculating unit 225 are intended for addition and output the calculated data GB and the second W data is supplied in the second sub frame calculated.

The data converter 221 converts the Ri, Gi, and Bi data of the three primary colors input from the system through the data input terminal into the RGCB data of the four primary colors as shown in FIG. 5A and outputs the RGCB data of the four primary colors to the gain calculator 222. Here, the method used for data conversion uses conventional techniques.

The gain calculator 222 calculates the highest gray value GV1max and the minimum gray value GV1min of the RC data of the first subframe among the four primary color RGCB data converted by the data converter 221, and then calculates the highest gray value GV1min. The maximum gray value GV1max and the minimum gray value GV1min are substituted into Equation 1 to calculate a gain, and output the gain to the data amplifier 223.

First Gain = (GV1max + GV1min) / GV1max

As shown in Equation 1, the gain calculator 222 divides the calculated sum of the highest gray value GV1max and the minimum gray value GV1 min by the highest gray value GV1max to calculate the quotient as the first gain. do.

In addition, the gain calculator 222 calculates the highest gray value GV2max and the minimum gray value GV2min of the GB data of the second subframe among the four primary color RGCB data converted by the data converter 221. Then, the maximum gray value GV2max and the minimum gray value GV2min are substituted into Equation 2 to calculate a gain, and output the gain to the data amplifier 223.

Second Gain = (GV2max + GV2min) / GV2max

As shown in Equation 2, the gain calculator 222 divides the calculated sum of the highest gray value GV2max and the minimum gray value GV2min by the highest gray value GV2max to calculate the quotient as a second gain. do.

The data amplifier 223 amplifies the gray value of the RC data by multiplying the gray value of the RC data of the first subframe by the calculated first gain as shown in FIG. 5B, and also as shown in FIG. 5C. The gray value of the GB data is amplified by multiplying the gray value of the GB data of the frame by the calculated second gain.

As shown in FIG. 5D, the gray calculator 224 calculates the minimum gray value GV3min among the RC data of the first subframe amplified by the data amplifier 223 and outputs it to the data calculator 225. . Here, the minimum gray value GV3min corresponds to a common denominator of RC data of the first subframe.

In addition, the gray scale calculator 224 calculates the minimum gray scale value GV4min among the GB data of the second subframe amplified by the data amplifier 223 and outputs the same to the data calculator 225 as illustrated in FIG. 5E. do. Here, the minimum gray value GV4min corresponds to a common denominator of GB data of the second subframe.

The data calculator 225 subtracts the gray scale value of the RC data of the first subframe amplified by the data amplifier 223 from the minimum gray scale value GV3min calculated by the gray scale calculator 224 to the data output stage. The Ro and Co data to be output are calculated, and first Wo data having the calculated minimum gray value GV3min is generated and output to the data output terminal. More specifically, the data calculating unit 225 executes the predetermined equations (3) and (4) to calculate the output Ro and Co data as shown in FIG. 5F, and also calculates the minimum gray value calculated as shown in FIG. GV3min) to generate Wo first data.

Ro = (first gain * R) -GV3min

As shown in Equation 3, the data calculator 225 calculates the minimum gray scale value calculated by the gray scale calculator 224 from the gray scale value of the R data of the first subframe amplified by the data amplifier 223. GV3min) is subtracted to calculate the output Ro data.

Co = (first gain * C) -GV3min

As shown in Equation 4, the data calculator 225 calculates the minimum gray scale value calculated by the gray scale calculator 224 from the gray scale value of the C data of the first subframe amplified by the data amplifier 223. GV3min) is subtracted to calculate the output Co data.

The data calculator 225 subtracts the gray scale value of the GB data of the second subframe amplified by the data amplifier 223 from the minimum gray scale value GV4min calculated by the gray scale calculator 224. In addition to calculating the Go and Bo data to be output to the output terminal, and generates the second Wo data having the calculated minimum gray value (GV4min) to output to the data output terminal. More specifically, the data calculator 225 executes the predetermined equations 5 and 6 to calculate the output Go and Bo data as shown in FIG. 5G, and also calculates the minimum gray value calculated as shown in FIG. 5G ( GV4min) to generate Wo second data.

Go = (2nd gain * G) -GV4min

As shown in Equation 5, the data calculator 225 may calculate the minimum gray value calculated by the gray calculator 224 from the gray value of the G data of the second subframe amplified by the data amplifier 223. GV4min) is subtracted to calculate the output Go data.

Bo = (gain * B) -GV4min

As shown in Equation 5, the data calculator 225 calculates the minimum gray scale value calculated by the gray scale calculator 224 from the gray scale value of the B data of the second subframe amplified by the data amplifier 223. GV4min) is subtracted to calculate the output Bo data.

On the other hand, the Wo first data generated by the data calculating unit 225 is the highest gray level value among the gray level values of the RC data of the first subframe amplified by the data amplifier 223 as shown in Equation 7 below. GV3max) and minimum gray scale value (GV3min) have a constant functional relationship.

Wo first data = f1 (GV3max, GV3min)

Here, f1 is a function having the highest gray value GV3max and the minimum gray value GV3min as variables.

Also, the Wo second data generated by the data calculator 225 may have the highest gray level value among the gray level values of the GB data of the second subframe amplified by the data amplifier 223 as shown in Equation 8 below. GV4max) and minimum gray scale value (GV4min) have a constant functional relationship.

Wo second data = f2 (GV4max, GV4min)

Here, f2 is a function having the highest gray value GV4max and the minimum gray value GV4min as variables.

By calculating the W data supplied in each subframe through the above-described process, the present invention can calculate the W data using the input RGB data while maintaining the R, G, C, and B colors.

As described above, the present invention calculates white data supplied from each subframe of one frame while maintaining the colors of R, G, C, and B, thereby increasing white luminance and providing cyan and yellow colors in each subframe. The brightness can be increased.

Although the technical spirit of the present invention has been described in detail according to the above preferred embodiment, it should be noted that the above embodiment is for the purpose of description and not of limitation. In addition, those skilled in the art will understand that various embodiments are possible within the scope of the technical idea of the present invention.

Claims (32)

A data converter for converting RGB data of the input frame including the first and second subframes into RGCB data; A gain calculator for calculating a first gain of RC first data of the first subframe among the converted RGCB data and calculating a second gain of GB first data of the second subframe; Amplifying the gray level value of the RC first data of the first subframe in proportion to the calculated first gain to output RC second data, and generating the GB second of the second subframe in proportion to the calculated second gain. A data amplifier for amplifying the gray level value of one data and outputting GB second data; A gray scale calculator for calculating a first minimum gray scale value in RC second data of the amplified first subframe and a second minimum gray scale value among GB second data of the amplified second subframe; And The RC third data and the W first data of the first subframe are calculated using the calculated first and second gains and the first and second minimum gray values, and the GB third of the second subframe is calculated. And a data calculator for calculating and outputting the data and the W second data. The method of claim 1, And the gain calculator calculates a first maximum gray value and a third minimum gray value of the RC first data of the first subframe. The method of claim 2, And the gain calculator divides the sum of the first highest gray value and the third minimum gray value by the first highest gray value and calculates a quotient of the first gain. 4. The method according to any one of claims 1 to 3, And the gain calculator calculates a second highest gray level value and a fourth minimum gray level value of the GB first data of the second subframe. 5. The method of claim 4, And the gain calculator divides the sum of the second highest gray value and the fourth lowest gray value by the second highest gray value and calculates a quotient thereof as the second gain. The method of claim 1, And the data amplifier multiplies the gray value of the RC first data of the first subframe by the first gain to amplify the gray value of the RC first data. 7. The method according to claim 1 or 6, And the data amplifier amplifies the gray value of the GB first data by multiplying the gray value of the GB first data of the second subframe by the second gain. The method of claim 1, And the data calculator is configured to calculate the RC third data by subtracting the first minimum gray value from the gray value of the RC second data of the amplified first subframe. The method according to claim 1 or 8, And the data calculator calculates the GB third data by subtracting the second minimum gray value from the gray value of the GB second data of the amplified second subframe. A plurality of data lines and a plurality of gate lines intersect, pixels are formed in the intersection regions, and G subpixels, W subpixels, and M subpixels are formed at the intersections of the data lines and the gate lines. ; After converting RGB data of an input frame consisting of first and second subframes into RGCB data and generating W first and second data to be supplied in the first and second subframes using the RGCB data, A data processor for outputting RC data and W first data of a first subframe and outputting GB data and W second data of the second subframe; A timing controller for controlling supply timing of RC data and W first data of the first subframe and GB data and W second data of the second subframe; Under the control of the timing controller, the liquid crystal is converted by converting RC data and W first data of the first subframe and GB data and W second data of the second subframe into analog data. A data driver for supplying the display panel; And Back light assembly for irradiating C light and Y light to the liquid crystal display panel sequentially Liquid crystal display comprising a. 11. The method of claim 10, The data processor, A data converter for converting RGB data of the input frame into RGCB data; A gain calculator for calculating a first gain of RC first data of the first subframe among the converted RGCB data and calculating a second gain of GB first data of the second subframe; Amplifying the gray level value of the RC first data of the first subframe in proportion to the calculated first gain to output RC second data, and generating the GB second of the second subframe in proportion to the calculated second gain. A data amplifier for amplifying the gray level value of one data and outputting GB second data; A gray scale calculator for calculating a first minimum gray scale value in RC second data of the amplified first subframe and a second minimum gray scale value among GB second data of the amplified second subframe; And The RC third data and the W first data of the first subframe are calculated using the calculated first and second gains and the first and second minimum gray values, and the GB third of the second subframe is calculated. And a data calculator for calculating and outputting the data and the W second data. The method of claim 11, And the gain calculator calculates a first maximum gray value and a third minimum gray value of the RC first data of the first subframe. 13. The method of claim 12, And the gain calculator divides the sum of the first highest gray value and the third minimum gray value by the first highest gray value and calculates a quotient of the first gain. The method of claim 11, And the gain calculator calculates a second highest gray level value and a fourth minimum gray level value of the GB first data of the second subframe. 15. The method of claim 14, And the gain calculator divides the sum of the second highest gray value and the fourth lowest gray value by the second highest gray value and calculates a quotient thereof as the second gain. The method of claim 11, And the data amplifier multiplies the gray value of the RC first data of the first subframe by the first gain to amplify the gray value of the RC first data. The method of claim 11, And the data amplifier amplifies the gray value of the GB first data by multiplying the gray value of the GB first data of the second subframe by the second gain. The method of claim 11, And the data calculator is configured to calculate the RC third data by subtracting the first minimum gray value from the gray value of the RC second data of the amplified first subframe. The method of claim 11, And the data calculator calculates the GB third data by subtracting the second minimum gray value from the gray value of the GB second data of the amplified second subframe. The method according to any one of claims 10 to 19, When the RC data and the W first data of the first subframe are input, the data driver supplies analog R data and C data to the M subpixel and the G subpixel, respectively, and supplies analog W first data to the W subpixel. Supplying a liquid crystal display device. 21. The method of claim 20, And the backlight assembly irradiates the C light to the liquid crystal display panel when the first subframe is driven. The method according to any one of claims 10 to 19, When the GB data and the W second data of the second subframe are input, the data driver supplies analog G data and B data to the G subpixel and M subpixel, respectively, and supplies analog W second data to the W subpixel. Supplying a liquid crystal display device. 23. The method of claim 22, And the backlight assembly irradiates the Y light to the liquid crystal display panel when the second subframe is driven. Converting RGB data of the input frame consisting of the first and second subframes into RGCB data; Calculating a first gain of RC first data of the first subframe among the converted RGCB data and calculating a second gain of GB first data of the second subframe; Amplifying the gray level value of the RC first data of the first subframe in proportion to the calculated first gain to output RC second data, and generating the GB second of the second subframe in proportion to the second gain Amplifying the gray level value of one data to output GB second data; Calculating a first minimum gray scale value among the RC second data of the amplified first subframe and calculating a second minimum gray scale value among the GB second data of the amplified second subframe; The RC third data and the W first data of the first subframe are calculated using the calculated first and second gains and the first and second minimum gray values, and the GB third of the second subframe is calculated. Calculating the data and the W second data Method of driving a liquid crystal display comprising a. 25. The method of claim 24, And in the gain calculating step, calculating a first highest gray value and a third minimum gray value of RC first data of the first subframe. 26. The method of claim 25, In the gain calculating step, driving the liquid crystal display according to claim 1, wherein the sum of the first highest gray value and the third minimum gray value is divided by the first highest gray value, and the quotient is calculated as the first gain. Way. 25. The method of claim 24, And in the gain calculating step, calculating a second highest gray value and a fourth minimum gray value of the GB first data of the second subframe. 28. The method of claim 27, In the gain calculating step, driving the liquid crystal display device by dividing an addition value of the second highest grayscale value and the fourth minimum grayscale value by the second highest grayscale value and calculating a quotient thereof as the second gain. Way. 25. The method of claim 24, And in the data amplifying step, multiply the gray value of the RC first data of the first subframe by the first gain to amplify the gray value of the RC first data. 25. The method of claim 24, And in the data amplifying step, amplifying the gray value of the GB first data by multiplying the gray value of the GB first data of the second subframe by the second gain. 25. The method of claim 24, And in the data calculating step, calculating the RC third data by subtracting the first minimum gray value from the gray value of RC second data of the amplified first subframe. 25. The method of claim 24, And in the data calculating step, calculating the GB third data by subtracting the second minimum gray value from the gray value of GB second data of the amplified second subframe.

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