KR101251377B1 - FSC LCD and driving method thereof - Google Patents

Abstract

The present invention relates to a liquid crystal display device and a driving method thereof which can improve display quality in field sequential color driving in which a panel is divided into a plurality of areas and simultaneously driven, and the display area is divided and driven by each gate driver. Since the double bank type data driver is configured to apply image data, it is possible to secure sufficient data write time for each liquid crystal pixel, and also because the data line and the pixel electrode do not overlap even when performing division driving. There is no distortion of the data, providing high quality image quality.

Description

Field sequential color liquid crystal display and driving method thereof

1 is a view for explaining a method of driving a field sequential color mode;

FIG. 2 is a diagram for describing 3-block division driving as an example of a block division driving method of an FSC liquid crystal display; FIG.

3 is a scan signal timing diagram for explaining a three-block division driving of the FSC liquid crystal display of FIG.

4 is a plan view illustrating a pixel structure of the 3-block split FSC liquid crystal display of FIG.

5 is a plan view briefly illustrating a configuration of an FSC liquid crystal display device according to a first embodiment of the present invention.

6 is a plan view briefly illustrating a configuration of an FSC liquid crystal display device according to a second embodiment of the present invention.

FIG. 7 is a view for explaining a difference in pixel structure between sub-regions of an FSC liquid crystal display according to a second exemplary embodiment of the present invention.

BRIEF DESCRIPTION OF THE DRAWINGS FIG.

A, B: 1st, 2nd area

a, b, c, d: first to fourth sub-areas

DD11 ~ DD14: First Data Driver

DD21 ~ DD24: Second Data Driver

GD1 to GD4: First to fourth gate drivers

20, 30: liquid crystal panel

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a display device, and more particularly, to a liquid crystal display device and a driving method thereof capable of improving display quality in field sequential color driving in which a panel is divided into a plurality of areas for simultaneous driving.

BACKGROUND ART [0002] Liquid crystal displays (LCDs), which tend to increase the practical use gradually, control a rotation angle of a liquid crystal in a plurality of liquid crystal cells arranged in a matrix form and a liquid crystal cell, respectively, (Backlight unit) is transmitted to a liquid crystal panel provided with a TFT (thin film transistor) for supplying image data for displaying a desired image on the screen.

As a light source used in such a backlight unit, a cold cathode fluorescent lamp (hereinafter referred to as 'CCFL') is mainly used. Such a backlight unit has a trend of miniaturization, thinness, and light weight. In accordance with this trend, light emitting diodes (LEDs), which are advantageous in terms of power consumption, weight, and brightness, have been proposed instead of CCFLs used in backlight units.

Through the backlight unit using the LED, the field sequential color (FSC) driving method is proposed to obtain better image quality.

Field sequential color (FSC) driving method drives LEDs of three primary colors (red, green, blue) sequentially without displaying color filters. This is a driving method which can display the mixed color by using the afterimage effect by a human eye.

More specifically, the display time of one frame on the panel is divided into three periods of red, green, and blue, and each backlight is sequentially illuminated with intervals in time.

As shown in FIG. 1, this FSC driving method is divided into three subframes (1 Sub-frame) of red (R), green (G) and blue (B) frame = 5.56 ms).

Each subframe is divided into a data writing time (DW = 1.69 ms) through TFT scanning, a liquid crystal response time (LR = 1.5 ms) according to data writing, and a backlight emitting time (BL = 2.37 ms) The time BL during which the backlight can be turned on is the time excluding the data writing time DW and the liquid crystal response time LR.

In the case of the FSC driving, data input to RGB to the liquid crystal panel is sequentially generated once at the same ratio (R: G: B = 1: 1: 1) within one vertical synchronizing period, and the corresponding backlight The light source is also synchronized in the same manner so that the red (R) light source, the green (G) light source, and the blue (B) light source are sequentially turned on. In this case, each light source is an LED lamp or a fluorescent lamp, and the red, green and blue light sources are sequentially arranged.

Recently, a block division driving method for dividing a liquid crystal panel into several blocks and driving each block simultaneously has been proposed for such an FSC liquid crystal display device.

This block division driving method will be briefly described with reference to FIG.

FIG. 2 is a diagram for explaining 3-block division driving in the block division driving method of an FSC liquid crystal display as an example. The display area of the liquid crystal panel 10 is divided into three blocks such as A, B, and C. FIG. .

Each block is simultaneously scanned and driven by each block through the independent gate drivers GD1, GD2, and GD3 located on one side of the liquid crystal panel 10, as illustrated in the scan signal timing diagram of FIG. 3. Each time the scan signal is output through the data drivers DD1 to DD4 located on the other side of (10), image data is output to each block and input to the corresponding pixel.

Since the three-block division driving method takes only one third of the scan driving time for displaying one screen, the application time of the scan signal, that is, the data writing time (DW in FIG. 1), is compared with the conventional non-dividing driving method. You can drive three times more. Since the application time of the scan signal is much longer than that of the conventional method, the accurate image data can be input to each pixel.

However, since the display area is divided into three regions and driven independently of each other, the number of data lines is increased by three times compared to the conventional one, and thus the aperture ratio of the pixel is lowered.

That is, referring to the plan view of one liquid crystal pixel structure of FIG. 4, two data lines are formed inside one pixel because three times the number of data lines must be formed to input separate image data into each of the three divided regions. The pixel structure in which DL2 and DL3 are configured to penetrate is shown. In this case, the exemplary pixel illustrated in FIG. 4 may have a 2-TFT pixel structure or a 1-TFT structure in which two thin film transistors TFT are connected to the gate line GL for switching driving. 'GL' in the figure represents a gate line. In addition, the thin film transistor TFT receives image data from the second data line DL2 and applies the image data to the pixel electrode PE, but the thin film transistor TFT has a first data line DL1 or a third data line. DL3) may be configured to receive the image data.

Like the above-described pixel structure, the aperture ratio of the pixel is lowered due to the pixel through structures of the second and third data lines DL2 and DL3, and is formed on the second and third data lines DL2 and DL3. The capacitance Csd is formed in the region M where the second and third data lines DL2 and DL3 and the pixel electrode PE overlap with each other by the pixel electrode PE. Image data applied to the data lines DL2 and DL3 is distorted, resulting in a problem of poor image quality such as crosstalk on the screen.

SUMMARY OF THE INVENTION The present invention has been made to solve the above problems, and further increases the aperture ratio compared to three-block unavoidable driving in an FSC mode liquid crystal display device, and also has an FSC liquid crystal display structure in which image quality defects such as crosstalk do not occur. The purpose is to provide a device.

The present invention to achieve the above object,

In the first draft ,

A substrate, a first data line formed in a first region on the substrate, a second data line formed in a second region independent of the first region on the substrate, and a gate line formed in each of the first region and the second region A liquid crystal panel including a liquid crystal pixel configured to intersect each of the data lines and the gate lines; A first data driver for outputting image data to the first data line; A second data driver for outputting image data to the second data line; A first gate driver for applying a scan signal to the gate line formed in the first region; A field sequential color liquid crystal display device including a second gate driver for applying a scan signal to a gate line formed in the second area is provided.

In the first proposal, the first data line and the second data line may be disconnected from each other.

In the first exemplary embodiment, the liquid crystal pixel may include a switching transistor connected to the first data line or the second data line and connected to the gate line, a liquid crystal capacitor and a storage capacitor connected to the switching transistor.

In the first proposal, the first and second data drivers are configured to face each other with the first area and the second area interposed therebetween.

In the second proposal ,

A substrate, first and second data lines formed in a first region on the substrate, third and fourth data lines formed in a second region independent of the first region on the substrate, and the first region and second A liquid crystal panel comprising a gate line formed in each of the regions, and a liquid crystal pixel configured in an area where the data lines and the gate lines cross each other; A first data driver for outputting image data to the first and second data lines; A second data driver for outputting image data to the third and fourth data lines; A first gate driver and a second gate driver configured to apply scan signals to the first sub region and the second sub region, each of which divides the first region; A field sequential color liquid crystal display device including a third gate driver and a fourth gate driver configured to apply a scan signal to a third sub area and a fourth sub area divided by the second area, respectively.

In the second aspect, the data lines formed in the first region and the second region may be disconnected from each other.

In the second aspect, the liquid crystal pixel may include a switching transistor connected to one of the first to fourth data lines and connected to the gate line, a liquid crystal capacitor and a storage capacitor connected to the switching transistor.

In the second proposal, the first and second data drivers may be configured to face each other with the first and second regions interposed therebetween.

In the second aspect, the liquid crystal pixels of the first sub region and the second sub region may be inputted with image data from the first data line and the second data line, respectively.

In the second aspect, the liquid crystal pixels of the third sub region and the fourth sub region may receive image data from the third data line and the fourth data line, respectively.

In a third proposal ,

A driving method of a field sequential color liquid crystal display device in which a display area is divided into first to fourth sub-areas,

A first step of simultaneously applying a scan signal to each of the sub-regions; A method of driving a field sequential color liquid crystal display device comprising a second step of inputting image data to each sub-region in synchronization with the scan signal is provided.

In the third aspect, the first step includes: configuring first to fourth gate drivers; And outputting the scan signal by mapping the first to fourth gate drivers to the first to fourth sub-regions.

In the third aspect, the second step comprises the steps of: configuring first and second data drivers; Outputting image data to the first and second sub-regions through the first data driver, and outputting image data to the third and fourth sub-regions through the second data driver.

In addition, the third method may further include a third step of sequentially irradiating red, green, and blue color light to each of the sub-regions.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will now be described in detail with reference to the accompanying drawings.

5 is a plan view briefly illustrating a configuration of an FSC liquid crystal display device according to a first embodiment of the present invention.

Looking at the configuration, the display area of the liquid crystal panel 20 in which a plurality of liquid crystal pixels are formed on the substrate is divided into first and second regions as shown in A and B. FIG. In this case, the liquid crystal pixel includes a switching transistor, a liquid crystal capacitor, and a storage capacitor. Of course, the switching transistor may be configured in parallel in a dual type.

First and second data drivers DD11 to DD14 and second data drivers for outputting image data to the first area A and the second area B, respectively, at two opposite ends of the liquid crystal panel 20 facing each other. DD21 to DD24 are respectively formed to form a double bank type.

In addition, first and second gate drivers GD1 and GD2 are configured at the other end of the liquid crystal panel 20 so as to allocate the first area A and the second area B, respectively, and output a scan signal.

Each of the drivers DD11 to DD14, DD21 to DD24, GD1, and GD2 is configured on the liquid crystal panel 20 or connected to the liquid crystal panel 20 through a tape carrier package (TCP). Can have

In addition, the liquid crystal panel 20 of the field sequential color liquid crystal display according to the present invention has a unique feature in forming data lines in the first region A and the second region B. It is a feature that the data lines of (A) and the second area (B) are configured not to be connected to each other. That is, the data line on the liquid crystal panel 20 is formed such that the first region A and the second region B are separately formed.

Accordingly, the data line (hereinafter, referred to as 'first data line') configured in the first area A receives image data from the first data drivers DD11 to DD14, and inputs the image data to the second area B. The configured data line (hereinafter referred to as 'second data line') receives image data from the second data drivers DD21 to DD24 and displays an image.

Accordingly, the first area A and the second area B are separately driven by the first and second gate drivers GD1 and GD2, and the first data drivers DD11 to DD14 and Image data may be received from the second data drivers DD21 to DD24 to be divided into separate display areas for displaying an image.

In brief, the operation of the first area A and the second area B is simultaneously performed by the first and second gate drivers GD1 and GD2, and thus the first data driver DD11 to DD14 and the second data drivers DD21 to DD24 also output image data in synchronization with the scan signal output of the first and second gate drivers GD1 and GD2, respectively. Will output to (B). Of course, after the image data is output, field sequential color driving is performed by sequentially irradiating red, green, and blue color light to the first and second regions A and B using red, green, and blue color LEDs (not shown). To perform.

The field sequential color liquid crystal display according to the first embodiment of the present invention in which the display area is divided into the first area A and the second area B, the gate driver is separately configured, and the data driver is configured as the double bank type as described above. Since the driving time of one frame is only 1/2 of that of the single bank type liquid crystal display device, the device can apply the gate-on interval of the scan signal twice as much, thereby improving the accuracy of the image data written to the liquid crystal pixel. Of course, since the data lines between the divided regions are formed independently, there is no overlapping configuration between the data lines and the pixel electrodes as in the dividing driving described in the prior art, so that distortion of image data does not occur, thereby providing high quality image quality. .

FIG. 6 is a plan view briefly showing a configuration of an FSC liquid crystal display device according to a second embodiment of the present invention, in which the same configuration as the first embodiment will be described with the same reference numeral.

Looking at the configuration, the display area of the liquid crystal panel 30 in which a plurality of liquid crystal pixels are formed on the substrate is divided into a first region and a second region (A, B). In this case, the liquid crystal pixel includes a switching transistor, a liquid crystal capacitor, and a storage capacitor. Of course, the switching transistor may be configured in parallel in a dual type.

First and second data drivers DD11 to DD14 for outputting image data to the first area A and the second area B, respectively, at two opposite ends of the liquid crystal panel 30 facing each other. DD21 to DD24 are respectively formed to form a double bank type.

In addition, in the second embodiment of the present invention, the first and second regions A and B are divided into two parts so that the whole is composed of the first to fourth sub regions a, b, c, and d. The first to fourth gate drivers GD1, GD2, GD3, and GD4 are configured at the other end of the liquid crystal panel 30 to allocate the first to fourth sub-regions a, b, c, and d, respectively. Output the signal.

Of course, each of the drivers DD11 to DD14, DD21 to DD24, and GD1 to GD4 is configured on the liquid crystal panel 30 or connected to the liquid crystal panel 30 through a tape carrier package (TCP). May have

In addition, the liquid crystal panel 30 of the field sequential color liquid crystal display according to the present invention has a unique feature in forming data lines in the first region A and the second region B. It is a feature that the data lines of (A) and the second area (B) are configured not to be connected to each other. That is, the data line on the liquid crystal panel 30 is formed such that the first region A and the second region B have separate shapes.

In addition, the data line for applying the image data to the first sub-region (a) and the second sub-region (b) and the image data for applying to the third sub-region (c) and the fourth sub-region (d) The data lines are configured separately, which will be described with reference to FIG. 7.

Referring to FIG. 7, a pixel structure of two sub-regions is illustrated, whereas the first sub-region (a) and the third sub-region (c) form a switching transistor (S) on the left side of the liquid crystal pixel. The subregion b and the fourth subregion d have a structure in which the switching transistor S is formed on the right side of the liquid crystal pixel. Of course, the configuration position of the switching transistor may be configured in the reverse of the above description.

Accordingly, the data lines formed in the first area A and the second area B may be positioned at right and left sides of one liquid crystal pixel, or two data lines may be disposed between adjacent pixels. In operation (A), odd-numbered data lines (hereinafter referred to as first data line DL1) are connected to liquid crystal pixels of the first sub-region a, and even-numbered data lines (hereinafter referred to as second data line DL2) And a liquid crystal pixel of the second sub-region b.

Similarly, in the second region B, odd-numbered data lines (hereinafter, third data line DL3) of the data lines are connected to the liquid crystal pixels of the third sub-region c and are even-numbered data lines (hereinafter, fourth). The data line DL4 is configured to be connected to the liquid crystal pixel of the fourth sub region d.

Accordingly, when the image data output from the first data drivers DD11 to DD14 is applied to the first data line DL1, an image is displayed in the first sub area a and the second data line DL2 is displayed. ) Is displayed in the second sub-area b. Similarly, the image data output from the second data drivers DD21 to DD24 is applied to the third data line DL3. When the image is displayed in the third sub area c and applied to the fourth data line DL4, the image is displayed in the fourth sub area d.

Accordingly, the first to fourth sub-regions a, b, c, and d are separately driven by the first to fourth gate drivers GD1 to GD4, and the first data driver DD11 to DD14 and second data drivers DD21 to DD24 may be divided into separate display areas for displaying images by receiving image data.

In brief, operation of the first to fourth sub-regions a, b, c, and d may be simultaneously performed by the first to fourth gate drivers GD1 to GD4. The data drivers DD11 to DD14 and the second data drivers DD21 to DD24 output image data in synchronization with the scan signal outputs of the first to fourth gate drivers GD1 to GD4 to output the first to fourth subs. An image is displayed in the areas a, b, c, and d. Of course, after outputting the image data, red, green, and blue color light are sequentially irradiated to the first to fourth sub-regions a, b, c, and d using red, green, and blue color LEDs (not shown). Perform field sequential color driving.

As described above, the display area is divided into the first to fourth sub areas a, b, c, and d, and the gate driver is separately configured, and the data driver is configured as the double bank type. In the field sequential color liquid crystal display device according to the second embodiment of the present invention having a different structure, the display area is divided into four areas to simultaneously perform image display. Since the driving time is only 1/4, the gate-on period of the scan signal can be increased by four times, which greatly improves the accuracy of image data written to the liquid crystal pixel, and also allows one display area to be divided into four sub-areas. Even when divided and driven, there is no overlapping area between the data line and the pixel electrode, so that distortion of the image data does not occur. There is an advantage that can offer.

In the field sequential color liquid crystal display device and the driving method thereof according to the present invention described above, the liquid crystal display device is divided into a display area, driven by each gate driver, and a double bank type data driver is applied to apply the image data. It is possible to secure sufficient data write time with pixels, and also provides a high-quality image quality without any distortion of the image data since the data line and the pixel electrode do not overlap even when the division driving is performed.

In addition, according to the second embodiment of the present invention, while performing the four-block split drive can be more secure than the three-block split drive described in the prior art it is a natural advantage to improve the product competitiveness will be.

Claims (14)

A substrate, first and second data lines formed in a first region on the substrate, third and fourth data lines formed in a second region independent of the first region on the substrate, and the first region and second A liquid crystal panel comprising a gate line formed in each of the regions, and a liquid crystal pixel configured in an area where the data lines and the gate lines cross each other; A first data driver for outputting image data to the first and second data lines; A second data driver for outputting image data to the third and fourth data lines; A first gate driver and a second gate driver configured to apply scan signals to the first sub region and the second sub region, each of which divides the first region; A third gate driver and a fourth gate driver which apply scan signals to the third sub-region and the fourth sub-region which divide the second region, respectively Including, The field sequential color liquid crystal display of the liquid crystal pixels of the first sub region and the second sub region, wherein image data is input from the first data line and the second data line, respectively. delete delete delete A substrate, first and second data lines formed in a first region on the substrate, third and fourth data lines formed in a second region independent of the first region on the substrate, and the first region and second A liquid crystal panel comprising a gate line formed in each of the regions, and a liquid crystal pixel configured in an area where the data lines and the gate lines cross each other; A first data driver for outputting image data to the first and second data lines; A second data driver for outputting image data to the third and fourth data lines; A first gate driver and a second gate driver configured to apply scan signals to the first sub region and the second sub region, each of which divides the first region; A third gate driver and a fourth gate driver which apply scan signals to the third sub-region and the fourth sub-region which divide the second region, respectively Including, The field sequential color liquid crystal display of the liquid crystal pixels of the third sub-region and the fourth sub-region, respectively, wherein image data is input from the third data line and the fourth data line. The method according to claim 1 or 5, Field sequential color liquid crystal display device characterized in that the data lines formed in the first region and the second region are disconnected from each other. Claim 7 has been abandoned due to the setting registration fee. The method according to claim 1 or 5, The liquid crystal pixel includes a switching transistor connected to one of the first to fourth data lines and connected to the gate line, a liquid crystal capacitor and a storage capacitor connected to the switching transistor. The method according to claim 1 or 5, And the first and second data drivers are arranged at positions facing each other with the first and second regions interposed therebetween, respectively. delete The display area is divided into first to fourth sub-areas, and includes first and second data lines extending in the first and second sub-regions, and third and fourth extending in the third and fourth sub-areas. A driving method of a field sequential color liquid crystal display including four data lines, A first step of simultaneously applying a scan signal to each of the sub-regions; A second step of inputting image data to each sub-area in synchronization with the scan signal; / RTI > The second step includes inputting image data into the first and second sub-regions through the first and second data lines, respectively. The display area is divided into first to fourth sub-areas, and includes first and second data lines extending in the first and second sub-regions, and third and fourth extending in the third and fourth sub-areas. A driving method of a field sequential color liquid crystal display including four data lines, A first step of simultaneously applying a scan signal to each of the sub-regions; A second step of inputting image data to each of the sub-areas in synchronization with the scan signal; / RTI > The second step includes inputting image data into the third and fourth sub-regions through the third and fourth data lines, respectively. The method according to claim 10 or 11, The first step, Configuring first to fourth gate drivers; Outputting the scan signal by mapping the first to fourth gate drivers to the first to fourth sub-areas respectively; Field sequential color liquid crystal display device driving method comprising a The method according to claim 10 or 11, The second step comprises: Configuring first and second data drivers; Outputting image data to the first and second sub-regions through the first data driver and outputting image data to the third and fourth sub-regions through the second data driver. Field sequential color liquid crystal display device driving method comprising a The method according to claim 10 or 11, A third step of sequentially irradiating red, green, and blue color light to each of the sub-regions Field sequential color liquid crystal display device driving method further comprising

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