KR20070070513A - A driving circuit of liquid crystal display device and a method for driving the same - Google Patents

Abstract

A driving circuit of an LCD device and a method for driving the same are provided to minimize motion burring on a caption by determining the motion of the caption based on the variation of a motion vector. A driving circuit of an LCD(Liquid Crystal Display) device includes a data modulating unit(333) and a timing controller(308). The data modulating unit receives data from the outside every frame, inserts first additional frame data, which has a different gray scale from the previous and following frame data, between the previous and following frame data when frame data has a caption, and outputs the inserted result. The timing controller realigns data from the data modulating unit, and supplies the realigned data to a data driver.

Description

A driving circuit of a liquid crystal display device and a driving method therefor {A driving circuit of liquid crystal display device and a method for driving the same}

1 is a view for explaining a method of driving a conventional liquid crystal display device.

FIG. 2 is a view illustrating a perceptive image felt by a viewer in a conventional liquid crystal display. FIG.

3 is a view showing a liquid crystal display device having a driving circuit of the liquid crystal display device according to an embodiment of the present invention.

FIG. 4 is a detailed configuration diagram of the data modulator of FIG. 3.

5 is a flowchart illustrating a method of driving a liquid crystal display according to an exemplary embodiment of the present invention.

6 is a view for explaining the size of a first additional frame inserted between frame data including subtitles in the liquid crystal display according to the present invention;

7 is a view for explaining the size of a second additional frame inserted between frame data not including subtitles in the liquid crystal display according to the present invention.

8 is a view for explaining a principle of reducing motion blur in a liquid crystal display according to an exemplary embodiment of the present invention.

* Explanation of symbols on the main parts of the drawings

333: Data modulation unit 401: First storage unit

402: second storage unit 403: data analysis unit

404: data alignment unit 405: motion vector extraction / decision unit

406: additional data generation / output unit 308: timing controller

CS: control signal

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a liquid crystal display device, and more particularly, to a driving circuit of a liquid crystal display device and a driving method thereof capable of improving the quality of a captioned image.

Liquid crystal displays (hereinafter, referred to as "LCDs") are becoming increasingly wider in scope due to their light weight, thinness, and low power consumption. According to this trend, LCDs are used for office automation equipment, audio / video equipment, and the like. On the other hand, the LCD is controlled to display the desired image on the screen by adjusting the transmission amount of the light beam according to the image signal applied to the plurality of control switches arranged in a matrix form.

LCDs having such a configuration are being replaced by cathode ray tube (CRT) displays due to their thin, low power consumption. The background of this change is the technological innovation of LCD quality improvement. In particular, there is a strong demand for moving picture display represented by television images in recent years, and improvements have been made by liquid crystal materials and driving methods.

However, while the cathode ray tube (CRT) is an impulse light emission by scanning an electron gun, the LCD uses a linear lamp (fluorescent light) as an illumination light source.

Because of the hold light emission using one backlight system, it is difficult to display a complete moving image. That is, when moving image display is performed by the LCD, so-called moving image contour deterioration occurs because of its hold characteristic, and image quality deteriorates.

Hereinafter, a driving method of a conventional liquid crystal display device will be described in detail with reference to the accompanying drawings.

1 is a view for explaining a driving method of a conventional liquid crystal display device.

A conventional liquid crystal display device samples data at a rate of 60 Hz, and supplies this sampled data on a liquid crystal panel at a rate of 120 Hz for high speed driving to complete one frame. That is, one frame data is represented for 1/120 second. In this way, as the driving speed is twice the sampling rate, as shown in FIG. 1A, the frame data 101 is supplied for one frame and the other one becomes empty. In this case, as shown in FIG. 1B, the conventional liquid crystal display supplies the same frame data 111 as the previous frame data once more to each of the empty frames.

However, due to such driving, the conventional liquid crystal display causes the following problems.

FIG. 2 is a view illustrating a perceived image felt by a viewer in a conventional liquid crystal display.

In FIG. 2, one rectangle represents one pixel, and FIG. 2 illustrates a time series of one pixel row.

First, the first frame data is supplied to the pixel rows in a half frame period. Then, this first frame data is maintained for 2/2 frame periods.

Thereafter, the first frame data is supplied once more in the 3/2 frame period. The first frame data supplied in this 3/2 frame period is maintained until the 4/2 frame period.

Here, if the image of the liquid crystal panel is moving at a speed of 4 pixels / 2 frames, the black pixels should move 4 pixels to the right during the 5/2 frame period. However, the conventional liquid crystal display does not express the state in which the pixels are completely moved in the fifth frame period due to the response speed of the liquid crystal. As a result, motion blur occurs.

As shown in Fig. 2, the size of the motion blur occurs a lot when a moving line representing eye movement passes through two or more types of pixels. That is, the size of the motion blur is more generated when the copper wire crosses the black pixel, the white pixel, and the gray pixel at the same time.

As shown in FIG. 2, a motion blur phenomenon of about four pixel distances is detected in the conventional LCD.

In particular, in the related art, the same frame data 111 is supplied once more for both the video with subtitles and the video without subtitles, resulting in many motion blurs in the video with subtitles.

SUMMARY OF THE INVENTION The present invention has been made to solve the above problems, and provides a driving circuit and a driving method thereof for reducing motion blur by inserting additional frame data having an intermediate gray level between frame data including subtitles. The purpose is.

In order to achieve the above object, the driving circuit of the liquid crystal display according to the present invention receives data supplied from the outside in units of frames, and when there is a subtitle in any frame data, data of a previous frame and data of a subsequent frame. A data modulator for inserting and outputting first frame data having a different gradation from data of a previous frame and subsequent frame data in between; And a timing controller for rearranging data from the data modulator and supplying the data driver to the data driver.

Here, the first additional frame data is characterized by having a gradation between the gradation of the previous frame data and the gradation of subsequent frame data.

The data modulator may insert second additional frame data having the same gray level as the data of the previous frame between the data of the previous frame and the data of the subsequent frame when there is no subtitle in the arbitrary frame data.

The data modulator may include a first storage unit configured to store frame data supplied from the outside; A second storage unit which reads and stores the most recently input and stored frame data into the first storage unit and supplies the stored last frame data back to the first storage unit; Analyzing the frame data stored in the first storage unit and outputting a first control signal when there is only frame data including subtitles in the first storage unit, only the frame data without the subtitles in the first storage unit A data analysis unit for outputting a second control signal if present, and outputting a third control signal when the first storage unit includes frame data including the subtitles and frame data without the subtitles; In response to the first control signal, a motion vector of the caption of the frame data including the caption is extracted from the first storage unit, and if there is a change in the motion vector, a fourth control signal is output and there is no change in the motion vector. Outputs a fifth control signal, extracts a motion vector of the caption of the frame data including the captions from the first storage in response to the third control signal, and outputs a sixth control signal if there is a change in the motion vector. A motion vector extraction / determination unit for outputting and outputting the fourth control signal when there is a change in the motion vector; Read frame data from the first and second storage units in response to the first, fourth, fifth, or sixth control signal, and the first additional frame data according to the first or fifth control signal. An additional frame data generation / output unit configured to output an output unit, output the second additional frame data according to the fourth control signal, and output first and second additional frame data according to the sixth control signal; And a data alignment unit for aligning and outputting the output from the additional frame data output unit and the image data from the first storage unit.

The data modulator may be embedded in the timing controller.

In addition, the driving method of the liquid crystal display device according to the present invention for achieving the above object, the step of inputting data frame by frame; Checking whether there is a subtitle in data of any frame; And when the data of the arbitrary frame has a subtitle, adding first additional frame data having a gradation between the data of the previous frame and the data of the subsequent frame between the data of the previous frame and the data of the subsequent frame. It is characterized by including the.

Here, the step of storing the data input for each frame for each frame; Analyzing the stored frame data; Checking whether there is frame data including subtitles among the stored frame data; And when there is no frame data including the caption, inserting second additional frame data having the same gray level as the previous frame data between each frame.

If frame data including subtitles exists among the stored frame data, confirming whether all of the stored frame data are frame data including subtitles; Extracting a motion vector from each frame data when the stored frame data are all frame data including subtitles; Determining whether the motion vector changes; Generating the first additional frame data when there is a change in the motion vector; And inserting the first additional frame data between the respective frame data.

Extracting a motion vector from the frame data including the subtitles when the stored frame data includes frame data including subtitles and frame data without subtitles; Determining whether the motion vector changes; Generating the first and second additional frame data when there is a change in the motion vector; And inserting the first additional frame data between each frame data including the subtitle, inserting the second additional frame data between each frame data not including the subtitle, and the second additional frame data. And inserting the frame data between the frame data including the subtitles and the frame data not including the subtitles.

Generating second additional frame data when there is no change in the motion vector; And inserting the second additional frame data between the respective frame data.

Hereinafter, a driving circuit of a liquid crystal display according to an exemplary embodiment of the present invention will be described in detail with reference to the accompanying drawings.

3 is a diagram illustrating a liquid crystal display device having a driving circuit of the liquid crystal display device according to an exemplary embodiment of the present invention.

In general, since the subtitle moves in one direction, the change direction in the previous frame or the subsequent frame is predictable. On the other hand, since the image changes indiscriminately, the direction of change is almost impossible to predict. The present invention is to prevent motion blur in this predictable subtitle, and has the following configuration for this purpose.

As shown in FIG. 3, the liquid crystal display according to the exemplary embodiment of the present invention includes a liquid crystal panel in which liquid crystal cells are formed in regions defined by data lines DL1 to DLm and gate lines GL0 to GLn. 302); A data driver 304 for supplying data Data to the data lines DL1 to DLm of the liquid crystal panel 302; A gate driver 306 for driving the gate lines GL0 to GLn of the liquid crystal panel 302; Receiving data supplied on a frame-by-frame basis from the system, and depending on whether subtitles are included in each frame data, first additional frame data, second additional frame data, or first and second additional frame data between the respective frame data. A data modulator 333 for inserting and outputting the data; And a timing controller 308 that aligns and outputs each frame data supplied from the data modulator 333 to a data driver.

The liquid crystal panel 302 is a liquid crystal is injected between the two substrates, the liquid crystal panel 302 is formed in the region defined by the data lines (DL1 to DLm) and the gate lines (GL0 to GLn) formed to be orthogonal to each other on the lower substrate. Thin Film Transistors (TFTs) are formed. The TFT supplies the data Data on the data lines DL1 to DLm to the liquid crystal cell Clc in response to the gate signal 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 302. 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 308 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.

Meanwhile, the data modulator 333 sequentially receives a predetermined number of frame data from the system, and distinguishes among them frame data including subtitles and frame data without subtitles.

Then, the first frame additional frame data having a gradation value between the previous frame data and the subsequent frame data is inserted between the frame data including the subtitles, and the same gradation value as the previous frame data is included between the frame data not including the subtitles. The second additional frame data is inserted.

In addition, the data modulator 333 inserts the second additional frame data between the data including the subtitles and the data without the subtitles.

Here, the data modulator 333 will be described in more detail as follows.

4 is a detailed block diagram illustrating the data modulator of FIG. 3.

As illustrated in FIG. 3, the data modulator 333 may include a first storage unit 401, a second storage unit 402, a data analyzer 403, a data alignment unit 404, and a motion vector extractor. The determination unit 405 and the additional data generation / output unit 406 are included.

Here, the components listed above will be described in more detail as follows.

The first storage unit 401 stores frame data sequentially supplied from the system one by one. In this case, in the first storage unit 401, only frame data including subtitles (hereinafter, referred to as 'subtitle frame data') may be stored, or frame data not including subtitles (hereinafter, 'non-subtitle frame'). Data ”may be stored, and the caption frame data and the non-caption frame data may be stored together.

The second storage unit 402 reads and stores the frame data lastly input and stored in the first storage unit 401.

That is, the second storage unit 402 stores the frame data last input in the n (n is a natural number) th set frame period.

The data analyzer 403 analyzes the frame data stored in the first storage unit 401 and outputs any one of the first to third control signals CS1 to CS3.

That is, the data analyzer 403 reads frame data stored in the first storage unit 401 and analyzes the frame data. The controller outputs any one of the first to third control signals CS1 to CS3 according to the analyzed result.

Specifically, when the frame data of the first storage unit 401 are all caption frame data, the data analyzer 403 outputs a first control signal CS1. When the frame data stored in the first storage unit 401 are all non-frame data, the data analyzer 403 outputs a second control signal CS2. When the frame data stored in the first storage unit 401 includes caption frame data and non-caption frame data, the third control signal CS3 is output.

The data analyzer 403 supplies the second control signal CS2 to the additional data generator / output unit 406 and extracts the motion vector from the first or third control signals CS1 and CS3. Supply to the determination unit 405.

The motion vector extraction / determination unit 405 performs different operations according to the first or third control signals CS1 and CS3 input from the data analysis unit 403.

First, when the first control signal CS1 is input to the motion vector extraction / determination unit 405, the motion vector extraction / determination unit 405 receives frame data from the first storage unit 401. That is, the caption frame data) is read. Then, a motion vector is detected from the frame data, and the detected motion vector is examined for change.

In this case, when there is a change in the motion vector, the motion vector extraction / determination unit 405 outputs a fourth control signal CS4 and supplies it to the additional data generation / output unit 406. That is, when there is a change in the motion vector, the motion vector extraction / determination unit 405 determines that the subtitles of the frame data are moving and outputs a fourth control signal CS4.

In response to the fourth control signal CS4, the additional data generator / output unit 406 may store the current set frame data stored in the first storage unit 401 and the previous set stored in the second storage unit 402. The last frame data of the frame is read, and each gray level of each of these frame data is calculated. Then, first additional frame data to be inserted between the respective frame data is generated. Then, the generated first additional frame data is supplied to the data alignment unit 404.

The data aligning unit 404 receives frame data from the first storage unit 401 at the time of input of the first additional frame data, and aligns the frame data with each of the first additional frame data. That is, the first additional frame data is inserted between the respective frame data. By doing so, the set of frame data input to the first storage unit 401 is modulated through the data alignment unit 404. The modulated set of frame data consists of the frame data and second additional frame data respectively located between the frame data.

Accordingly, frame data is positioned before and after each of the first additional frame data, wherein each of the first additional frame data has a gray level between the gray level of the preceding frame data and the gray level of the rear frame data. That is, each of the first additional frame data has a gray level between the gray level of previous frame data and the gray level of subsequent frame data.

Thereafter, the modulated frame data output from the data alignment unit 404 is input to the timing controller 308, and the timing controller 308 supplies the modulated data to the data driver 304 at an appropriate timing.

As described above, when the frame data stored in the first storage unit 401 are all caption frame data, and the captions of the caption frame data are moving captions, the data modulator 333 is provided between the respective frame data. By inserting one additional frame data, motion blur for moving subtitles is prevented.

On the other hand, when there is no change in the motion vector, the motion vector extraction / determination unit 405 outputs a fifth control signal CS5. The fifth control signal CS5 is supplied to the additional data generation / output unit 406. That is, when there is no change in the motion vector, the motion vector extraction / determination unit 405 determines that the subtitles of the frame data do not move and outputs the fifth control signal CS5.

In response to the fifth control signal CS5, the additional data generator / output unit 406 may store the current set frame data stored in the first storage unit 401 and the previous set frame stored in the second storage unit 402. Read the last frame data of and calculate each gray level of each of these frame data. Then, second additional frame data to be inserted between the respective frame data is generated. Then, the generated second additional frame data is supplied to the data alignment unit 404.

The data aligning unit 404 receives frame data from the first storage unit 401 at the time of input of the second additional frame data, and aligns the frame data with each of the second additional frame data. That is, the second additional frame data are respectively inserted between the respective frame data. By doing so, the set of frame data input to the first storage unit 401 is modulated through the data alignment unit 404. The modulated set of frame data consists of the frame data and second additional frame data respectively inserted between the frame data.

Accordingly, frame data is positioned before and after each of the second additional frame data. In this case, the gray level of each second additional frame data is the same as the gray level of the preceding frame data. That is, each second additional frame data has the same gradation as that of the previous frame data from itself.

Thereafter, the modulated frame data output from the data alignment unit 404 is input to the timing controller 308, and the timing controller 308 supplies the modulated data to the data driver 304 at an appropriate timing.

As such, when all of the frame data stored in the first storage unit 401 are caption frame data, but the captions of the caption frame data are the closed captions, the data modulation unit 333 respectively includes a second between each frame data. By inserting the additional frame data, motion blur on the image is prevented.

Meanwhile, the second control signal CS2 output from the data analyzer 403 is directly input to the additional data generator / output unit 406 instead of the motion vector extractor / decision unit 405.

In this case, in response to the second control signal CS2, the additional data generation / output unit 406 transfers the current set frame data stored in the first storage unit 401 and the previous data stored in the second storage unit 402. The last frame data of the set frame is read, and each gray level of each of these frame data is calculated. Then, the gray level of the second additional frame data to be inserted between the respective frame data is calculated. Then, the calculated second additional frame data is supplied to the data alignment unit 404.

The data aligning unit 404 receives frame data from the first storage unit 401 at the time of input of the second additional frame data, and aligns the frame data with each of the second additional frame data. That is, the second additional frame data are respectively inserted between the respective frame data. By doing so, the set of frame data input to the first storage unit 401 is modulated through the data alignment unit 404. The modulated set of frame data consists of the frame data and second additional frame data respectively inserted between the frame data.

Accordingly, frame data is positioned before and after each of the second additional frame data. In this case, the gray level of each second additional frame data is the same as the gray level of the preceding frame data.

Thereafter, the modulated frame data output from the data alignment unit 404 is input to the timing controller 308, and the timing controller 308 supplies the modulated data to the data driver 304 at an appropriate timing.

As described above, when the frame data stored in the first storage unit 401 are all non-frame frame data, the data modulator 333 inserts second additional frame data between the respective frame data to provide motion for the image. Prevent blur.

On the other hand, when the third control signal CS3 is input to the motion vector extraction / determination unit 405, the motion vector extraction / determination unit 405 receives the frame data (from the first storage unit 401). That is, caption frame data and non-caption frame data) are read. Then, a motion vector is detected from the frame data (subtitle frame data), and the detected motion vector is examined for change.

In this case, when there is a change in the motion vector, the motion vector extraction / determination unit 405 outputs a sixth control signal CS6 and supplies it to the additional data generation / output unit 406. That is, when there is a change in the motion vector, the motion vector extraction / determination unit 405 determines that the caption of the frame data is moving and outputs a sixth control signal CS6.

In response to the sixth control signal CS6, the additional data generator / output unit 406 may store the current set frame data stored in the first storage unit 401 and the previous set stored in the second storage unit 402. The last frame data of the frame is read, and each gray level of each of these frame data is calculated. Then, first and second additional frame data to be inserted between the respective frame data are generated. Then, the generated first and second additional frame data are supplied to the data alignment unit 404.

That is, the additional data generation / output unit 406 generates first and second additional frame data in response to the sixth control signal CS6.

The data aligning unit 404 receives frame data from the first storage unit 401 at the time of input of the first and second additional frame data, and aligns the frame data with the respective first and second additional frame data. Let's do it. That is, the second additional frame data are respectively inserted between the non-column frames among the frame data. The first additional frame data is respectively inserted between the caption frame data among the frame data.

The second additional frame data is respectively inserted between the caption frame data and the non-caption frame data. By doing so, the set of frame data input to the first storage unit 401 is modulated through the data alignment unit 404. This modulated set of frame data consists of the frame data and first and second additional frame data respectively inserted between the frame data.

Accordingly, frame data is positioned before and after each of the first additional frame data, wherein each of the first additional frame data has a gray level between the gray level of the preceding frame data and the gray level of the rear frame data.

Subtitle frame data is located before and after each of the second additional frame data, or subtitle frame data and non-caption frame data are located, wherein each second additional frame data is a gray level of the frame data located at the front. Has

Thereafter, the modulated frame data output from the data alignment unit 404 is input to the timing controller 308, and the timing controller 308 supplies the modulated data to the data driver 304 at an appropriate timing. .

On the other hand, when there is no change in the motion vector, the motion vector extraction / determination unit 405 outputs a fifth control signal CS5. The fifth control signal CS5 is supplied to the additional data generation / output unit 406. That is, when there is no change in the motion vector, the motion vector extraction / determination unit 405 determines that the subtitles of the frame data do not move and outputs the fifth control signal CS5.

In response to the fifth control signal CS5, the additional data generation / output unit 406 calculates each gray level of the respective frame data. Then, second additional frame data to be inserted between the respective frame data is generated. Then, the calculated second additional frame data is supplied to the data alignment unit 404.

The data aligning unit 404 receives frame data from the first storage unit 401 at the time of input of the second additional frame data, and aligns the frame data with each of the second additional frame data. That is, the second additional frame data are respectively inserted between the respective frame data. By doing so, the set of frame data input to the first storage unit 401 is modulated through the data alignment unit 404. The modulated set of frame data consists of the frame data and second additional frame data respectively located between the frame data.

Accordingly, frame data is positioned before and after each of the second additional frame data. In this case, the gray level of each second additional frame data is the same as the gray level of the preceding frame data.

Thereafter, the modulated frame data output from the data alignment unit 404 is input to the timing controller 308, and the timing controller 308 supplies the modulated data to the data driver 304 at an appropriate timing.

As described above, when the frame data stored in the first storage unit 401 are non-capacitive frame data and caption frame data, but the captions of the caption frame data are stopped, the data modulator 333 intersects each frame data. Motion blur for the image is prevented by inserting the second additional frame data into each of them.

When the frame data stored in the first storage unit 401 are non-capacitive frame data and caption frame data, and the captions of the caption frame data are moving captions, the data modulator 333 is configured for each non-caption frame. Inserting a second additional frame data frame between the data, a second additional frame data between each non-caption frame and the subtitle frame, and inserting a first additional frame data frame between each subtitle frame data. Prevents motion blur for motion blur and pictures.

The data modulator 333 may be embedded in the timing controller 308 to reduce the size of the driving circuit.

Next, a driving method of the liquid crystal display device according to an exemplary embodiment of the present invention will be described.

5 is a flowchart illustrating a method of driving a liquid crystal display according to an exemplary embodiment of the present invention.

First, a predetermined number of frame data are sequentially input (1S).

Then, it is checked whether there is frame data including subtitles among the frame data. That is, it is checked whether there is caption frame data among the frame data (2S).

Next, if there is frame data including subtitles among the frame data (subtitle frame data), it is checked whether all of the frame data are made of subtitle frame data (3S).

Subsequently, when the frame data are all caption frame data, a motion vector is detected from each caption frame data (4S).

Thereafter, whether the motion vector is changed is checked (5S), and if there is a change in the motion vector, first additional frame data is generated (6S).

Next, the first additional frame data is inserted between each subtitle frame data (7S). Subsequently, the modulated frame data is output (8S).

On the other hand, if no subtitle frame data is included in the frame data in step 2S, second additional frame data is generated (2-1S), and the second additional frame data is inserted between each frame data (2 -2S). Then, the frame data modulated in this manner is output.

On the other hand, when the non-caption frame data and the caption frame data are mixed in step 3S, the motion vector for the caption frame data is extracted (3-1S), and the extracted motion vector is checked for change (3-2S). ).

When there is a change in the motion vector, first and second additional frame data are generated (3-3S), and the first additional frame data is inserted between the subtitle frame data, respectively, and the second additional frame data. Is inserted between each non-film frame data (3-4S). In addition, the second additional frame data is inserted between the non-capacitive frame data and each subtitle frame data (3-4S). Subsequently, the modulated frame data is output (8S).

On the other hand, when there is no change of the motion vector in step 3-2S, the second additional frame data is generated (2-1S).

Thereafter, the second additional frame data is inserted between the respective frame data (2-2S). Then, the frame data modulated in this manner is output.

FIG. 6 is a view for explaining the size of a first additional frame inserted between frame data including subtitles in the liquid crystal display according to the present invention.

As illustrated in FIG. 6, first frame data 601 having a gray scale between the gray scale of the previous frame data 600 and the gray scale of the subsequent frame data 602 is inserted between each frame data including the caption.

FIG. 7 is a view for explaining the size of a second additional frame inserted between frame data not including subtitles in the liquid crystal display according to the present invention.

As shown in FIG. 7, second additional frame data 701 having the same gray level as the previous frame data 700 is inserted between each frame data that does not include captions.

8 is a view for explaining the principle of the motion blur is reduced in the liquid crystal display according to an embodiment of the present invention.

In FIG. 8, one rectangle represents one pixel, and FIG. 2 illustrates a time series of one pixel row.

First, the first frame data is supplied to the pixel rows in a half frame period. Then, this first frame data is maintained for 2/2 frame periods.

Then, in the 3/2 frame period, the first additional frame data having a gray level between the first frame data and the third frame data is supplied. The first frame data supplied in this 3/2 frame period is maintained until the 4/2 frame period.

Here, if the image of the liquid crystal panel is moving at a speed of 4 pixels / 2 frames, the black pixels should move 4 pixels to the right during the 5/2 frame period. At this time, since the second additional frame data has a gray level of the first frame data and a gray level of the third frame data, the motion blur is reduced.

As shown in Fig. 8, the size of the motion blur occurs a lot when a moving line representing eye movement passes through two or more types of pixels. That is, the size of the motion blur is more generated when the copper wire crosses the black pixel, the white pixel, and the gray pixel at the same time. However, in the present invention, almost all the moving lines pass only one type of pixel, thereby reducing the size of the motion blur.

As shown in FIG. 2, a motion blur phenomenon of about one pixel distance is detected in a conventional liquid crystal display.

The present invention described above is not limited to the above-described embodiments 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.

As described above, the driving circuit and the driving method thereof of the liquid crystal display according to the present invention have the following effects.

In the driving circuit of the liquid crystal display according to the present invention, frame data including subtitles and frame data without subtitles are distinguished, and a motion vector is extracted from the frame data including the subtitles.

Then, by determining whether the motion vector is changed or not, the motion of the caption is determined, and either one of the first additional frame data and the second additional frame data is inserted between the frame data according to the determined result.

Here, the first additional frame data is a value having a value between the gradation of the data of the previous frame and the gradation of the data of the subsequent frame, and inserts the first additional frame data between each subtitle frame data to provide a motion blur for the subtitle. Can be minimized.

Claims (10)

The first additional frame data having a different gradation from the data of the previous frame and the data of the subsequent frame between the data of the previous frame and the data of the subsequent frame when data supplied from the outside is supplied in units of frames and there is a subtitle in the arbitrary frame data. A data modulator for inserting and outputting the inserted data; And, And a timing controller for rearranging data from the data modulator and supplying the data driver to a data driver. The method of claim 1, And the first additional frame data has a gradation between the gradation of the previous frame data and the gradation of subsequent frame data. The method of claim 1, And the data modulator inserts the second additional frame data having the same gray level as the data of the previous frame between the data of the previous frame and the data of the subsequent frame when there is no caption in any of the frame data. Driving circuit. The method of claim 3, wherein The data modulator, A first storage unit which stores frame data supplied from the outside; A second storage unit which reads and stores frame data lastly input and stored in the first storage unit; Analyzing the frame data stored in the first storage unit and outputting a first control signal when there is only frame data including subtitles in the first storage unit, only the frame data without the subtitles in the first storage unit A data analysis unit for outputting a second control signal if present, and outputting a third control signal when the first storage unit includes frame data including the subtitles and frame data without the subtitles; In response to the first control signal, a motion vector of the caption of the frame data including the caption is extracted from the first storage unit, and if there is a change in the motion vector, a fourth control signal is output and there is no change in the motion vector. Outputs a fifth control signal, extracts a motion vector of the caption of the frame data including the captions from the first storage in response to the third control signal, and outputs a sixth control signal if there is a change in the motion vector. A motion vector extraction / determination unit for outputting and outputting the fourth control signal when there is a change in the motion vector; And, Read frame data from the first and second storage units in response to the first, fourth, fifth, or sixth control signal, and the first additional frame according to the first or fifth control signal. An additional frame data generation / output unit for outputting data, outputting the second additional frame data according to the fourth control signal, and outputting first and second additional frame data according to the sixth control signal; And, And a data alignment unit for aligning and outputting the output from the additional frame data generation / output unit and the image data from the first storage unit. The method of claim 1, And the data modulator is embedded in the timing controller. Inputting data frame by frame; Checking whether there is a subtitle in data of any frame; And, If the data of the any frame has subtitles, adding first additional frame data having a gradation between the data of the previous frame and the data of the subsequent frame between the data of the previous frame and the data of the subsequent frame; Method of driving a liquid crystal display device characterized in that. The method of claim 6, Storing the data input for each frame for each frame; Analyzing the stored frame data; Checking whether there is frame data including subtitles among the stored frame data; And, And if there is no frame data including the caption, inserting second additional frame data having the same gray level as previous frame data between each frame. The method of claim 6, When there is frame data including subtitles among the stored frame data, Confirming whether the stored frame data are all frame data including subtitles; Extracting a motion vector from each frame data when the stored frame data are all frame data including subtitles; Determining whether the motion vector changes; Generating the first additional frame data when there is a change in the motion vector; And, And inserting the first additional frame data between the frame data. The method of claim 8, When the stored frame data includes frame data including subtitles and frame data without subtitles, Extracting a motion vector from the frame data including the caption; Determining whether the motion vector changes; Generating the first and second additional frame data when there is a change in the motion vector; And, Inserting the first additional frame data between each frame data including the subtitle, inserting the second additional frame data between each frame data not including the subtitle, and inserting the second additional frame data into the And inserting between frame data including subtitles and frame data without subtitles. The method of claim 9, If there is no change in the motion vector, Generating second additional frame data; And, And inserting the second additional frame data between the frame data.

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