KR101127820B1 - Apparatus and method for driving of liquid crystal display - Google Patents

Abstract

The present invention relates to a driving device and a method of driving a liquid crystal display device capable of improving image quality by driving an Octically Compensated Bend mode liquid crystal in a field sequential driving method. In the driving apparatus of the liquid crystal display according to the present invention, the OSC mode liquid crystal driven by the voltage difference applied to the pixel electrode and the common electrode is disposed between the data lines and the gate lines in a matrix form. A liquid crystal panel including liquid crystal cells, a backlight unit for irradiating light of a first color, a second color, and a third color to the liquid crystal panel, and black data and a first color and a first color for each subframe of one frame; A data driver for sequentially supplying one of two color and third color video data to the data line, a gate driver for driving the gate lines, the data driver, the gate driver, and the backlight unit Control the black data and the video data to the data driver for each sub-frame. And a timing control section for supplying to optional.

By such a configuration, the present invention can prevent the OSC mode liquid crystal from transitioning from the band state to the splay state, thereby improving image quality, and applying a stable white voltage to the liquid crystal cell.

Description

Apparatus and method for driving a liquid crystal display {APPARATUS AND METHOD FOR DRIVING OF LIQUID CRYSTAL DISPLAY}

1 is a view schematically showing a driving device of a general liquid crystal display.

FIG. 2 is a perspective view illustrating the liquid crystal panel shown in FIG. 1. FIG.

3 is a cross-sectional view illustrating an arrangement state of an OCB mode liquid crystal according to an electric field applied to the liquid crystal cell illustrated in FIG. 2.

4 is a graph showing transmittance of an electric field applied to the OCB mode liquid crystal cell shown in FIG. 3.

5 is a schematic view of a driving device of a liquid crystal display according to an exemplary embodiment of the present invention.

FIG. 6 is a waveform diagram illustrating a driving waveform for driving the liquid crystal panel shown in FIG. 5.

FIG. 7 is a view showing a data selector shown in FIG. 5; FIG.

FIG. 8 is a graph showing transmittance of an electric field applied to an OCB mode liquid crystal cell of the embodiment of the present invention shown in FIG. 5.

<Explanation of Signs of Major Parts of Drawings>

2, 102 liquid crystal panel 4, 104 data driver                 

6, 106: gate driver 8, 108: timing control unit

110: backlight unit 112: light source drive unit

114: green light source 116: red light source

118: blue light source 120: data alignment unit

130: data selector 132: counter

134: selection unit

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a liquid crystal display, and more particularly, to an apparatus and a method of driving a liquid crystal display device capable of improving image quality by driving an Optically Compensated Bend mode liquid crystal in a field sequential driving method.

A liquid crystal display displays an image by adjusting light transmittance of liquid crystal cells according to video data. Among the liquid crystal display devices, an active matrix type in which switching elements are provided for each liquid crystal cell is suitable for displaying a moving image. In an active matrix liquid crystal display device, a thin film transistor (hereinafter referred to as TFT) is mainly used as a switching element. Such liquid crystal display devices can be miniaturized compared to CRTs, and are widely used in personal computers and notebook computers, as well as office automation devices such as photocopiers, mobile devices such as cell phones and pagers. .                         

Referring to FIG. 1, a driving apparatus of a general liquid crystal display device includes a liquid crystal panel 2 in which liquid crystal cells are arranged in a matrix, and a data driver for driving data lines DL1 to DLm of the liquid crystal panel 2. 4), the gate driver 6 for driving the gate lines GL0 to GLn of the liquid crystal panel 2, and the timing controller 8 for controlling the data driver 4 and the gate driver 6. Equipped.

In the liquid crystal panel 2, liquid crystal is injected between two substrates, and the data lines DL1 to DLm and the gate lines GL0 to GLn are formed to be orthogonal to each other on the lower substrate, and the TFTs are formed in the intersection area. Is formed. The TFT supplies video data on the data lines DL1 to DLm to the liquid crystal cell Clc in response to a gate pulse supplied to the gate lines GL0 to GLn. For this purpose, the gate electrode of the TFT is connected to the gate line GL, and the source electrode is connected to the data line DL. The drain electrode of the TFT is connected to the pixel electrode of the liquid crystal cell Clc. In addition, the storage capacitor Cst is formed in the liquid crystal cell Clc of the liquid crystal panel 2. The storage capacitor Cst is formed between the pixel electrode of the liquid crystal cell Clc and the front gate line, or is formed between the pixel electrode of the liquid crystal cell Clc and the common electrode to maintain a constant voltage of the liquid crystal cell Clc. .

The timing controller 8 arranges the source data RGB input from the outside to be suitable for driving the liquid crystal panel 2 and supplies the source data RGB to the data driver 4. The timing controller 8 generates the data control signal DCS and the gate control signal GCS using the horizontal / vertical synchronization signals Vsync and Hsync and the main clock MCLK input from the outside. Here, the data control signal DCS includes a dot clock Dclk, a source start pulse SSP, a source shift clock SSC, a source output enable SOE, and a polarity. Control signal POL and the like. The gate control signal GCS includes a gate start pulse GSP, a gate shift clock GSC, a gate output enable GOE, and the like.

The data driver 4 samples the data from the timing controller 8 according to the data control signal DCS from the timing controller 8, and then latches the sampled data Data by one line. The converted data Data is converted into analog video data corresponding to the gamma voltage and supplied to the data lines DL.

The gate driver 6 includes a shift register for sequentially generating gate pulses in response to the gate start pulse GSP among the gate control signals GCS from the timing controller 8, and the voltage of the gate pulses to drive the liquid crystal cell. Level shifter for shifting to a suitable level. The gate driver 6 sequentially supplies the gate pulses to the gate lines GL by performing a shift operation in response to the gate shift clock GSC when the gate start pulse GSP is supplied from the timing controller 8. do. In response to this gate pulse, the TFT is turned on so that analog video data is supplied to the pixel electrode of the liquid crystal cell via the data line DL.

In such a liquid crystal display driving device, a liquid crystal injected between two substrates of the liquid crystal panel 2 is generally mainly used in a twisted nematic (TN) mode. . The liquid crystal of the TN mode has a twisted angle of 90 °, and transmits light by changing the liquid crystal array state according to the application of an electric field. In the liquid crystal of the TN mode, the vibration directions of the light vibrating in the long axis direction of the liquid crystal molecules and the light vibrating in the direction perpendicular to the long axis direction are different from each other. Such a change in refractive index of light is called refractive anisotropy, and the refractive anisotropy has a problem in that the liquid crystal in the TN mode has a narrow viewing angle and a slow response speed of the liquid crystal. In order to solve the drawbacks of the TN mode liquid crystal, an in-plane switch (hereinafter referred to as "IPS") mode, an Optically Compensated Bend (hereinafter referred to as "OCB") mode, etc. Liquid crystals have been developed.

The liquid crystal of IPS mode is favorable to wide viewing angle due to the horizontal electric field, but the response time is slow as about 10 ~ 60 (ms). On the other hand, the liquid crystal of the OCB mode is structurally advantageous to the wide viewing angle, and the response time is about 3 to 11 (ms) faster than that of the TN mode liquid crystal.

2 and 3, the liquid crystal panel 2 employing the OCB mode liquid crystal includes an upper substrate 10 in which a color filter array (not shown) and an alignment layer are sequentially formed, and a TFT (not shown). The lower substrate 12 having the array and the alignment layer formed thereon, the upper substrate 10 and the lower substrate 12 have a predetermined gap by a spacer (not shown) and the liquid crystal 18 of the OCB mode injected into the predetermined space; Upper and lower polarizers 14 and 22 disposed outside the upper and lower substrates 10 and 12, an upper compensation film 16 disposed between the upper substrate 10 and the upper polarizer 14, and a lower substrate. The compensation film 20 is disposed between the lower polarizer 22 and the lower polarizer 22 to compensate the viewing angle by delaying the phase of incident light.

The alignment layers of the upper substrate 10 and the lower substrate 12 are aligned in the same direction. The liquid crystal of the OCB mode injected between the upper substrate 10 and the lower substrate 12 maintains a splay state, which is an initial alignment state, under a specific voltage Vth according to the alignment processing direction of the alignment layer. That is, the liquid crystal molecules are arranged at tilt angles of θ and -θ ° on the surfaces of the upper and lower alignment layers, respectively, and the tilt angle decreases toward the center of the liquid crystal cell, thereby decreasing the tilt angle of the liquid crystal molecules at the center of the liquid crystal cell. 0 °.

The optical characteristics of the liquid crystal molecules arranged in such a splay state will be described with reference to FIG. 4.

The liquid crystal molecules having a splay state transition to a bend state at a voltage higher than a specific voltage Vth. Here, the time taken for the liquid crystal molecules in the splay state to transition to the band state is called a transition time. Such a transition time from the splay state to the band state is severely changed at a specific voltage (Vth) and transmits light irregularly with respect to the increasing voltage (V). Accordingly, spots or flickers appear in the image for a short time by the liquid crystal having the splay state. In addition, since the white voltage White is formed at a voltage equal to or greater than a specific voltage Vth in the driving method of the general OCB mode, the white brightness corresponding to the white voltage is unstable and the image quality is deteriorated. Further, in the driving method of the general OCB mode, when the transition time of the liquid crystal molecules in the splay state is severely changed at a specific voltage Vth, the transition from the band state to the splay state is not possible to display a desired image.

In addition, in the driving device of the conventional liquid crystal display, the liquid crystal panel 2 has a disadvantage in that the luminance is low because light from the backlight unit is lost to about 1/3 or less due to the color filter array.

Accordingly, in order to solve the above problems, the present invention is to provide an apparatus and method for driving a liquid crystal display device that can improve the image quality by driving the Opsi ratio (Bens) mode liquid crystal in the field sequential driving method.

The driving apparatus of the liquid crystal display according to the embodiment of the present invention for achieving the above object is arranged by the data lines and the gate lines intersect in a matrix form and is driven by a voltage difference applied to the pixel electrode and the common electrode. A liquid crystal panel including liquid crystal cells in which an Occically Compensated Bend mode liquid crystal is injected between two substrates, a backlight unit for irradiating light of a first color, a second color, and a third color to the liquid crystal panel; A data driver for sequentially supplying one of black data, video data of a first color, a second color, and a third color to the data line for each subframe of a frame; and a gate for driving the gate lines A driver, the data driver, the gate driver, and the backlight unit, each sub-frame It characterized by a timing control unit for selectively supplying a black data group and the video data to the data driver.

Each of the sub-frames in the driving apparatus may include any one of a first period of supplying the black data to the liquid crystal cell and video data of the first color, the second color, and the third color following the first period. And a second period for supplying the liquid crystal cell, and a third period for irradiating the liquid crystal panel with any one of the first color, the second color, and the third color following the second period. .

In the method of driving the liquid crystal display according to the exemplary embodiment of the present invention, an Optically Compensated Bend mode in which data lines and gate lines cross each other in a matrix form and is driven by a voltage difference applied to a pixel electrode and a common electrode. A method of driving a liquid crystal display device comprising a liquid crystal panel having liquid crystal cells injected with liquid crystal between two substrates; Each frame is driven by dividing one frame into a plurality of subframes. Each of the plurality of subframes includes any one of a first step of supplying black data to the liquid crystal cell and video data of first to third colors. And a third step of irradiating the liquid crystal panel with any one of a second step of supplying the light to the first to third colors.

In the driving method of the liquid crystal display, each of the plurality of subframes may include supplying a first gate pulse to the gate line such that the black data is supplied to the liquid crystal cell, and supplying the video data to the liquid crystal cell. And supplying two gate pulses to the gate line.

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

FIG. 5 is a view illustrating a driving apparatus of a liquid crystal display according to an exemplary embodiment of the present invention, in which a liquid crystal cell into which an Optically Compensated Bend mode liquid crystal is injected is arranged in a matrix form and a liquid crystal panel 102. The backlight unit 110 sequentially irradiates green (G), red (R), and blue (R) light, and black data and video data are sequentially applied to each subframe of one frame of the liquid crystal panel 102. A data driver 104 for supplying the data lines DL1 to DLm, a gate driver 106 for driving the gate lines GL0 to GLn of the liquid crystal panel 102, a data driver 104, Controlling the gate driver 106 and the backlight unit 110 and selectively supplying any one of green (G), red (R), and blue (R) and black data to the data driver 104 in each subframe. With a timing controller 108 for the .

In the liquid crystal panel 102, OSC mode liquid crystal is injected between two substrates, and the data lines DL1 to DLm and the gate lines GL0 to GLn are orthogonal to each other on the lower substrate. TFTs are formed in the area. The TFT supplies video data on the data lines DL1 to DLm to the liquid crystal cell Clc in response to a gate pulse supplied to the gate lines GL0 to GLn. For this purpose, the gate electrode of the TFT is connected to the gate line GL, and the source electrode is connected to the data line DL. The drain electrode of the TFT is connected to the pixel electrode of the liquid crystal cell Clc. In addition, the storage capacitor Cst is formed in the liquid crystal cell Clc of the liquid crystal panel 102. The storage capacitor Cst is formed between the pixel electrode of the liquid crystal cell Clc and the front gate line, or is formed between the pixel electrode of the liquid crystal cell Clc and the common electrode to maintain a constant voltage of the liquid crystal cell Clc. .                     

The backlight unit 110 may include a green light source 114 for irradiating green light G to the liquid crystal panel 102, a red light source 116 for irradiating red light R to the liquid crystal panel 102, and And a blue light source 118 for irradiating blue light B to the liquid crystal panel 102, and a light source driver 112 for driving each of the green, red, and blue light sources 114, 116, and 118.

Each of the green, red, and blue light sources 114, 116, and 118 generates the green light G, the green light source 114, and the red light R in response to the driving signal of the light source driver 112. Check). Each of these green and red and blue light sources 114, 116, 118 may be a fluorescent lamp or a light emitting diode.

The light source driver 112 sequentially drives each of the green, red, and blue light sources 114, 116, and 118 for one frame in response to the light source control signal LCS from the timing controller 108. That is, the light source driver 112 drives the green light source 114 for a part of the first subframe of one frame in response to the light source control signal LCS, and the red light source 116 for the part of the second subframe. Drive the blue light source 118 for a portion of the third sub-frame.

The timing controller 108 generates the data control signal DCS and the gate control signal GCS using the horizontal / vertical synchronization signals Vsync and Hsync and the main clock MCLK. Here, the data control signal DCS includes a dot clock Dclk, a source start pulse SSP, a source shift clock SSC, a source output enable SOE, and a polarity. Control signal POL and the like. The gate control signal GCS includes a gate start pulse GSP, a gate shift clock GSC, a gate output enable GOE, and the like. In this case, as shown in FIG. 6, the gate start pulse GSP includes first and second pulses P1 and P2 generated in dual in each subframe of one frame.

In addition, as shown in FIG. 6, the timing controller 108 uses the horizontal / vertical synchronization signals Vsync and Hsync and the main clock MCLK supplied from the outside to each subframe SF1, SF2, and SF3. At the second half of the), one of the green, red, and blue light sources 114, 116, and 118 generates a light source control signal LCS for driving and supplies the light source control signal LCS to the backlight unit 110.

In addition, the timing controller 108 rearranges the source data RGB input from the outside so as to be suitable for driving the liquid crystal panel 102, and arranges green G aligned for each subframe SF1, SF2, SF3 of one frame. ), And one of red (R) and blue (R) and black data are selectively supplied to the data driver 104. To this end, the timing controller 108 includes a data aligner 120 and a data selector 130.

The data aligning unit 120 controls the green (G), red (R), and blue (R) data (G_Data, R_Data, B_Data) so that the source data RGB input from the outside is suitable for driving the liquid crystal panel 102. The data is rearranged to be supplied to the data selector 130. That is, in order to drive the liquid crystal panel 102 in the field sequential driving method, the data aligning unit 120 greens the source data RGB input from the outside so as to correspond to each subframe SF1, SF2, SF3 of one frame. (G) and red (R) and blue (R) data (G_Data, R_Data, B_Data) are rearranged in the order.

As shown in FIG. 7, the data selector 130 counts a vertical sequential signal Vfscsync for field sequential driving to generate a data selection signal DSS, and selects data from the counter 132. According to the signal DSS, the data G_Data, R_Data and B_Data and the black data (that is, the base voltage) of green (G), red (R), and blue (R) supplied from the data alignment unit 120 are selected. A selection unit 134 for supplying the data driver 104 is provided.

The counter 132 counts each rising edge of the field sequential driving vertical synchronization signal Vfscsync corresponding to the gate start pulse GSP, and selects the data selection signal DSS corresponding to the counting value to the selection unit 134. Supply. The counter 132 is reset every one frame period, that is, every horizontal sync signal Vsync.

The selection unit 134 is a first to which the rearranged green (G), red (R) and blue (R) data (G_Data, R_Data, B_Data) and black data (base low pressure) are supplied from the data alignment unit 120. And a sixth input terminal, and a selection signal input terminal and an output terminal to which the data selection signal DSS from the counter 132 is supplied.

The odd-numbered, ie first, third and fifth input terminals of the plurality of input terminals are electrically connected to the ground voltage source GND to receive the ground voltage. The second input terminal of the plurality of input terminals is electrically connected to the green (G) data (G_Data) input line, and the fourth input terminal is electrically connected to the red (R) data (R_Data) input line. The sixth input terminal is electrically connected to the blue (R) data B_Data input line.                     

The selector 134 is a base voltage from the base voltage source GND when the data selection signal DSS corresponding to each of the counting values of '1', '3' and '5' is supplied from the counter 134. That is, black data is selected and supplied to the data driver 104. On the other hand, when the data selection signal DSS corresponding to the counting value of '2' is supplied from the counter 134, the selector 134 is selected from the green G from the data G_Data input line. Data G_Data is selected and supplied to the data driver 104. In addition, when the data selection signal DSS corresponding to the counting value of '4' is supplied from the counter 134, the selector 134 may be configured to display the red R from the data R_Data input line of the red R. Data R_Data is selected and supplied to the data driver 104. When the data selection signal DSS corresponding to the counting value of '6' is supplied from the counter 134, the selector 134 may be configured as the blue B from the data B_Data input line. Data B_Data is selected and supplied to the data driver 104.

As a result, the selector 134 sequentially supplies the black data and the green (G) data R_Data to the data driver 104 in the first subframe SF1 of one frame, and then selects the second subframe SF2. The black data and the red (R) data (R_Data) are sequentially supplied to the data driver 104 during the period, and the black data and the blue (B) data (B_Data) are supplied to the data driver during the third subframe (SF3) period. 104).

The data driver 104 samples the data Data supplied from the selector 134 of the timing controller 108 in accordance with the data control signal DCS from the timing controller 108, and then sampled the data Data. Is latched by one line and the latched data is converted into analog video data corresponding to the gamma voltage and supplied to the data lines DL. Accordingly, the data driver 104 supplies black data to the data lines DL during the first period T1 of each subframe SF1, SF2, SF3, and the second period T2. In the meantime, any one of the data G_Data, R_Data, and B_Data of green G, red R, and blue R is supplied to the data lines DL.

The gate driver 106 shifts the shift register for generating the gate pulse sequentially in response to the gate start pulse GSP among the gate control signals GCS from the timing controller 108, and applies the gate pulse voltage to driving the liquid crystal cell. Level shifter for shifting to a suitable level. As shown in FIG. 6, when the gate start pulse GSP is dually supplied to each subframe SF1, SF2, SF3 of one frame from the timing controller 108, the gate driver 106 receives a gate shift. By performing a shift operation in response to the clock GSC, dual gate pulses are sequentially supplied to the gate lines GL. That is, the gate driver 106 is configured to supply the black data to the liquid crystal cell using the first pulse P1 of the dual gate start pulses GSP for each subframe SF1, SF2, SF3 of one frame. A gate pulse is generated and sequentially supplied to the gate lines GL, and among the data G_Data, R_Data, and B_Data of green (G), red (R), and blue (R) using the second pulse (P2). A second gate pulse for supplying any one to the liquid crystal cell is generated and sequentially supplied to the gate lines GL.

5 and 6, a driving apparatus and a method of a liquid crystal display according to an exemplary embodiment of the present invention will be described.

First, each subframe SF1, SF2, SF3 of one frame includes a first period T1 supplied to black data and data of red (G), red (R), and blue (R). The second period T2 to which any one of G_Data, R_Data and B_Data is supplied is divided into a third period T3 to turn on the backlight unit 110.

Specifically, in the first period T1 of the first subframe SF1, the first gate pulse generated by the first pulse P1 of the dual gate start pulse GSP is supplied to the gate line GL. Black data selected by the selection unit 134 is supplied to the data line DL of the liquid crystal panel 102 so as to be synchronized with this. Accordingly, the liquid crystal cell of the liquid crystal panel 102 into which the OSC mode liquid crystal is injected is transitioned to a band state by black data supplied from the data line DL. Then, in the second period T2 of the first subframe SF1, the second gate pulse generated by the second pulse P2 of the dual gate start pulse GSP is supplied to the gate line GL. In synchronization with this, the green G data G_Data selected by the selection unit 134 is supplied to the data line DL of the liquid crystal panel 102. Accordingly, the liquid crystal cell of the liquid crystal panel 102 into which the OSC mode liquid crystal is injected transitions the OSC mode liquid crystal in a band state so as to correspond to the green (G) data (G_Data) voltage supplied from the data line DL. . Subsequently, in the third period T3 of the first subframe SF1, the green G among the green, red, and blue light sources 114, 116, and 118 in response to the light source control signal LCS of the timing controller 108 is performed. The light source 114 is turned on and irradiated to the liquid crystal panel 102. Accordingly, the liquid crystal cell of the liquid crystal panel 102 into which the OSC mode liquid crystal is injected displays the green image corresponding to the green data G_Data by adjusting the transmission amount of the green light from the green (G) light source 114. Done.

Similarly, in the first period T1 of the second subframe SF2, as in the first subframe SF1, black data is supplied to the data line DL to supply the black data to the OSC mode liquid crystal. The liquid crystal cell of the panel 102 is kept in a band state. Then, in the second period T2 of the second subframe SF2, the liquid crystal cell of the liquid crystal panel 102 into which the OSC mode liquid crystal is injected by supplying the red (R) data R_Data to the data line DL. Is a transition of the OSC mode liquid crystal in the band state to correspond to the red (R) data (R_Data) voltage. Subsequently, in the third period T3 of the second sub-frame SF2, the liquid crystal cell of the liquid crystal panel 102 into which the OSC mode liquid crystal is injected is adjusted by adjusting the amount of red light transmitted from the red light source 116. The red image corresponding to the data R_Data is displayed.

Similarly, in the first period T1 of the third subframe SF3, as in the first and second subframes SF1 and SF2, the black data is supplied to the data line DL so as to be in the OSC mode. The liquid crystal cell of the liquid crystal panel 102 into which the liquid crystal is injected is maintained in a band state. Then, in the second period T2 of the third subframe SF3, the liquid crystal cell of the liquid crystal panel 102 into which the OSB mode liquid crystal is injected by supplying the blue (B) data B_Data to the data line DL. The transition of the OBS ratio liquid crystal in the band state to correspond to the blue (R) data (B_Data) voltage. Subsequently, in the third period T3 of the third sub-frame SF3, the liquid crystal cell of the liquid crystal panel 102 into which the OSC mode liquid crystal is injected is adjusted by adjusting the amount of blue light transmitted from the blue (B) light source 118. The blue image corresponding to the data B_Data is displayed.

Accordingly, the driving apparatus and method of the liquid crystal display according to the exemplary embodiment of the present invention additionally mix the green, red, and blue images of the first to third subframes SF1, SF2, and SF3 to display a desired color image.

As described above, the driving apparatus and method of the liquid crystal display according to the exemplary embodiment of the present invention time-division one frame into the first to third subframes SF1, SF2, SF3, and By supplying black data every first period T1, the OSC mode liquid crystal is always kept in the band state so that the LCD does not transition from the band state to the splay state.

Therefore, the driving device and method of the liquid crystal display according to the exemplary embodiment of the present invention transfer the OSC mode liquid crystal to the band state for each subframe SF1, SF2, SF3 as shown in FIG. 8, and then supply data. By doing so, it is possible to prevent the phenomenon of smearing or flickering in the image for a short time by the liquid crystal having the splay state. In addition, the driving apparatus and method of the liquid crystal display according to the exemplary embodiment of the present invention may not transmit the OSC mode liquid crystal from the band state to the splay state in each subframe SF1, SF2, SF3, and the white luminance according to the white voltage. Can be transmitted stably.

In addition, the driving apparatus and method of the liquid crystal display according to the exemplary embodiment of the present invention divide the one frame into a plurality of subframes and sequentially drive the red, green, and blue light to the liquid crystal panel 102. By removing the color filter array of the liquid crystal panel 102 to increase the light transmittance it is possible to increase the brightness.

On the other hand, the present invention described above is not limited to the above-described embodiment and the accompanying drawings, it is possible that various substitutions, modifications and changes within the scope without departing from the technical spirit of the present invention It will be apparent to those skilled in the art.

The driving apparatus and method of the liquid crystal display according to the embodiment of the present invention as described above can increase the luminance by increasing the light transmittance of the liquid crystal panel using the field sequential driving method. In addition, in the present invention, the black data is supplied to the liquid crystal cell in the initial period of each sub-frame of the field sequential driving method, the OSC mode liquid crystal is transferred to the band state, and then the desired data is supplied to the liquid crystal cell to display an image. The image quality can be improved by preventing the non-mode liquid crystal from transitioning from the band state to the splay state, and a stable white voltage can be applied to the liquid crystal cell.

Claims (9)

Liquid crystal cells including liquid crystal cells in which data lines and gate lines are arranged to cross each other in a matrix, and an Optically Compensated Bend mode liquid crystal driven by a voltage difference applied to a pixel electrode and a common electrode is injected between two substrates. Panel, A backlight unit for irradiating light of a first color, a second color, and a third color to the liquid crystal panel; A data driver for sequentially supplying one of black data and video data of a first color, a second color, and a third color to the data line for each subframe of one frame; A gate driver for driving the gate lines; A timing controller for controlling the data driver, the gate driver, and the backlight unit and selectively supplying the black data and the video data to the data driver for each sub-frame, and The timing controller may include a data alignment unit for rearranging source data input from the outside in the order of the video data of the first color, the second color, and the third color, and the first color and the second from the data alignment unit. And a data selector for selectively supplying video data and black data of a color and a third color to the data driver. The method of claim 1, Each of the subframes, A first period of supplying the black data to the liquid crystal cell, A second period of supplying one of video data of the first color, the second color, and the third color to the liquid crystal cell following the first period; And a third period of illuminating the liquid crystal panel with any one of the first color, the second color, and the third color following the second period. The method of claim 2, The timing controller may be configured to correspond to the dual gate start pulses corresponding to the first and second periods and the third period by using a synchronization signal including a first vertical synchronization signal and a horizontal synchronization signal from the outside. And a light source control signal for controlling the light source. delete The method of claim 1, The data selection unit, A counter which is reset according to the first vertical synchronizing signal and counts a second vertical synchronizing signal corresponding to the dual gate start pulse to generate a data selection signal; And a selector which selectively supplies one of black data and video data of the first color, the second color, and the third color according to the data selection signal. The method of claim 5, The selection unit, Selecting the black data and the video data of the first color in a first subframe in response to the data selection signal, and sequentially supplying the black data and the video data of the first color to the data driver; Selecting the black data and the video data of the second color in a second subframe in response to the data selection signal, and sequentially supplying the black data and the video data of the second color to the data driver; And the black data and the video data of the third color are sequentially supplied to the data driver in response to the data selection signal in a third subframe. The method of claim 3, wherein The backlight unit, A light source of the first to third colors, And a light source driver for sequentially turning on light sources of the first to third colors according to the light source control signal. A liquid crystal panel having liquid crystal cells in which data lines and gate lines are arranged to cross each other in a matrix form, and an Optically Compensated Bend mode liquid crystal driven by a voltage difference applied to a pixel electrode and a common electrode is injected between two substrates. And a data alignment unit for rearranging source data input from an external source in order of video data of a first color, a second color, and a third color, and the first, second, and second colors from the data alignment unit. A driving method of a liquid crystal display device comprising a timing controller having a data selector for selectively supplying three-color video data and black data to a data driver; Drives one frame divided into a plurality of sub-frames, Each of the plurality of subframes, Supplying the black data to the liquid crystal cell; A second step of supplying any one of the video data of the first to third colors to the liquid crystal cell; And a third step of irradiating any one of first to third colors of light to the liquid crystal panel. The method of claim 8, Each of the plurality of subframes, Supplying a first gate pulse to the gate line such that the black data is supplied to the liquid crystal cell; And supplying a second gate pulse to the gate line such that the video data is supplied to the liquid crystal cell.

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