Patent Publication Number: US-8994706-B2

Title: Display panel and driving method thereof

Description:
BACKGROUND OF THE INVENTION 
     1. Field of the Invention 
     The present invention relates to a display panel, and more particularly, to a display panel capable of improving image quality. 
     2. Description of the Prior Art 
     Because a liquid crystal display (LCD) panel has advantages of thin appearance, low power consumption, and low radiation, the liquid crystal display has been widely applied in various electronic products for panel displaying. The operation of the liquid crystal display panel is featured by varying voltage drops between opposite sides of a liquid crystal layer for twisting the angles of the liquid crystal molecules in the liquid crystal layer so that the transmittance of the liquid crystal layer can be controlled for illustrating images with the aid of light provided by a backlight module. In general, a liquid crystal display panel comprises a plurality of pixels, a scan driver, and a data driver. The data driver is configured to provide a plurality of data signals to the plurality of pixels via data lines. The scan driver is configured to output a plurality of scan signals to turn on corresponding pixels via scan lines. 
     When resolution of the liquid crystal display panel is higher, the scan driver needs to turn on the pixels at higher frequency, correspondingly, time for turning on the pixel is shorter. If time for turning on the pixel is insufficient, the data signals can not be written into the pixels completely, so as to affect images of the liquid crystal display panel. Especially, when the liquid crystal display panel is utilized to display 3D images, the scan driver needs to turn on the pixels at twice of the original frequency, such that time for turning on the pixel is decreased to a half of the original time. The liquid crystal display panel of the prior art may have bad image quality, or even can not display images correctly when displaying high resolution images or 3D images due to insufficient time for turning the pixels. 
     SUMMARY OF THE INVENTION 
     The present invention provides a display panel, comprising a plurality of pixels, each of the plurality of pixels comprising a main sub-pixel and a secondary sub-pixel; a plurality of first scan lines, each of the plurality of first scan lines being coupled to main and secondary sub-pixels of a row of pixels; a plurality of second scan lines, each of the plurality of second scan lines being coupled to secondary sub-pixels of a row of pixels; a plurality of first data lines, each of the plurality of first data lines being coupled to main and secondary sub-pixels of (N+1)th and (N+2)th rows of pixels; a plurality of second data lines, each of the plurality of second data lines being coupled to main and secondary sub-pixels of (N+3)th and (N+4)th rows of pixels; a scan driver, coupled to the first and second scan lines, for turning on the main and secondary sub-pixels of the pixels via the plurality of first scan lines during a first period of a frame period, and turning on the secondary sub-pixels of the pixels via the plurality of second scan lines during a second period of the frame period; and a data driver, coupled to the first and second data lines, for outputting data signals to the turned on main and secondary sub-pixels via the first and second data lines; wherein N is a multiple of 4, and N≧0. 
     The present invention further provides a driving method of a display panel, comprising providing a display panel comprising a plurality of pixels, a plurality of first scan lines, a plurality of second scan lines, a plurality of first data lines, a plurality of second data lines, a scan driver, and data driver, each of the plurality of pixels comprising a main sub-pixel and a secondary sub-pixel, each of the plurality of first scan lines being coupled to main and secondary sub-pixels of a row of pixels, each of the plurality of second scan lines being coupled to secondary sub-pixels of a row of pixels, each of the plurality of first data lines being coupled to main and secondary sub-pixels of (N+1)th and (N+2)th rows of pixels, each of the plurality of second data lines being coupled to main and secondary sub-pixels of (N+3)th and (N+4)th rows of pixels, wherein N is a multiple of 4, and N≧0; the scan driver turning on the main and secondary sub-pixels of the pixels via the plurality of first scan lines during a first period of a frame period; the scan driver turning on the secondary sub-pixels of the pixels via the plurality of second scan lines during a second period of the frame period; and the data driver outputting data signals to the turned on main and secondary sub-pixels via the first and second data lines. 
     These and other objectives of the present invention will no doubt become obvious to those of ordinary skill in the art after reading the following detailed description of the preferred embodiment that is illustrated in the various figures and drawings. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  is a diagram showing a display panel of the present invention. 
         FIG. 2  is a diagram showing the display panel of the present invention driving pixels when displaying 2D images. 
         FIG. 3  is a diagram showing the display panel of the present invention driving pixels when displaying 3D images. 
         FIG. 4  is a diagram showing another embodiment of the display panel of the present invention driving pixels when displaying 3D images. 
         FIG. 5  is a flowchart showing a driving method of the display panel of the present invention. 
         FIG. 6  is a diagram showing another embodiment of the display panel of the present invention driving pixels when displaying 3D images. 
         FIG. 7  is a flowchart showing another driving method of the display panel of the present invention. 
     
    
    
     DETAILED DESCRIPTION 
     Please refer to  FIG. 1 .  FIG. 1  is a diagram showing a display panel of the present invention. As shown in  FIG. 1 , the display panel  100  of the present invention comprises a plurality of pixels P, a plurality of first scan lines Ga, a plurality of second scan lines Gb, a plurality of first data lines Da, a plurality of second data lines Db, a scan driver  110 , and a data driver  120 . Each of the pixels P comprises a main sub-pixel Pa and a secondary sub-pixel Pb. An area of the main sub-pixel Pa is smaller than an area of the secondary sub-pixel Pb. Each of the first scan lines is coupled to main sub-pixels Pa and secondary sub-pixels Pb of a row of pixels P. Each of the second scan lines is coupled to secondary sub-pixels Pb of a row of pixels P. Each of the first data lines Da is coupled to main sub-pixels Pa and secondary sub-pixels Pb of (N+1)th and (N+2)th rows of pixels P (N is a multiple of 4, and N≧0). Each of the plurality of second data lines is coupled to main sub-pixels Pa and secondary sub-pixels Pb of (N+3)th and (N+4)th rows of pixels P. The scan driver  110  is coupled to the first scan lines Ga and the second scan lines Gb, for turning on the main sub-pixels Pa and secondary sub-pixels Pb of a row of the pixels P via a first scan lines Ga, and turning on the secondary sub-pixels Pb of a row of the pixels P via a second scan lines Gb. The data driver  120  is coupled to the first and second data lines Da, Db, for outputting data signals to the turned on main and secondary sub-pixels Pa, Pb via the first and second data lines Da, Db. 
     According to the above arrangement, when the display panel  100  of the present invention displays images, the scan driver  110  can turn on the main and secondary sub-pixels Pa, Pb via the first scan lines Ga to display main images, and then on the secondary sub-pixels Pb via the second scan lines Gb to display auxiliary images, so as to improve image quality of the display panel  100 . Especially when the display panel  100  of the present invention displays 3D images, the auxiliary images can improve image quality of lateral visual angle images for reducing crosstalk effect. 
     Please refer to  FIG. 2 , and refer to  FIG. 1  as well.  FIG. 2  is a diagram showing the display panel of the present invention driving pixels when displaying 2D images. As shown in  FIG. 2 , when the display panel  100  displays 2D images, the scan driver  110  is configured to turn on main and secondary sub-pixels Pa, Pb of first and third rows of the pixels P via two of the first scan lines Ga 1 , Ga 3  during a period T 1  of a frame period for displaying main images, to turn on main and secondary sub-pixels Pa, Pb of second and fourth rows of the pixels P via two of the first scan lines Ga 2 , Ga 4  during a period T 2  of the frame period for displaying main images, to turn on the secondary sub-pixels Pb of the first and third rows of the pixels P via two of the second scan lines Gb 1 , Gb 3  during a period T 3  of the frame period for displaying auxiliary images, to turn on the secondary sub-pixels Pb of the second and fourth rows of the pixels P via two of the second scan lines Gb 2 , Gb 4  during a period T 4  of the frame period for displaying auxiliary images, and so on. 
     In addition, time for displaying auxiliary images by the first and third rows of the pixels P is not limited to be in the period T 3 . Time for displaying auxiliary images by the first and third rows of the pixels P can be shifted to be in other period (such as the period T 2  or the period T 4 ) according to design requirement for better image quality. Similarly, time for displaying auxiliary images by the second and fourth rows of the pixels P is not limited to be in the period T 4 . Moreover, the time for displaying auxiliary images by the first and third rows of the pixels P is not limited to be before the time for displaying auxiliary images by the second and fourth rows of the pixels P. 
     According to the above arrangement, since the scan driver  110  can turn on two rows of pixels P during a same period, and the data driver  120  can output different data signals to pixels P at a same column but a different row, correspondingly, time for turning on the pixels can be doubled. Therefore, when the display panel  100  of the present invention displays 2D images with higher resolution, the data driver  120  has enough time to completely write the data signals into the pixels P. 
     Please refer to  FIG. 3 , and refer to  FIG. 1  as well.  FIG. 3  is a diagram showing the display panel of the present invention driving pixels when displaying 3D images. As shown in  FIG. 3 , when the display panel  100  displays 3D images, the scan driver  110  is configured to turn on main and secondary sub-pixels Pa, Pb of first to fourth rows of the pixels P via four of the first scan lines Ga 1 -Ga 4  during a period T 1  of a frame period for displaying main images, to turn on main and secondary sub-pixels Pa, Pb of fifth to eighth rows of the pixels P via four of the first scan lines Ga 5 -Ga 8  during a period T 2  of the frame period for displaying main images, to turn on the secondary sub-pixels Pb of the first to fourth rows of the pixels P via four of the second scan lines Gb 1 -Gb 4  during a period T 3  of the frame period for displaying auxiliary images, to turn on the secondary sub-pixels Pb of the fifth to eighth rows of the pixels P via four of the second scan lines Gb 5 -Gb 8  during a period T 4  of the frame period for displaying auxiliary images, and so on. 
     In addition, time for displaying auxiliary images by the first to fourth rows of the pixels P is not limited to be in the period T 3 . Time for displaying auxiliary images by the first to fourth rows of the pixels P can be shifted to be in other period (such as the period T 2  or the period T 4 ) according to design requirement for better image quality. Similarly, time for displaying auxiliary images by the fifth to eighth rows of the pixels P is not limited to be in the period T 4 . Moreover, the time for displaying auxiliary images by the first to fourth rows of the pixels P is not limited to be before the time for displaying auxiliary images by the fifth to eighth rows of the pixels P. 
     According to the above arrangement, the scan driver  110  can turn on four rows of pixels P during a same period, and the data driver  120  can output data signals to two rows of pixels P via the first data lines Da, and output data signals to another two rows of pixels P via the second data lines during the same period. Therefore, when the display panel  100  of the present invention is utilized to display 3D images, even the scan driver  110  needs to turn on the pixels P at twice of the original frequency, time for turning on the pixels P still can be doubled. Therefore, when the display panel  100  of the present invention displays 3D images, the data driver  120  has enough time to completely write the data signals into the pixels P. 
     In addition, when the display panel  100  displays 3D images, original resolution (ex. 1920×1080) of left visual images and right visual images is roughly equal to one fourth of resolution of the display panel (ex. 3840×2160). The data driver  120  can generate data signals with larger vertical resolution (2160) according to data signals with the original vertical resolution (1080), and outputs the data signals with larger vertical resolution via the first data lines Da and the second data lines Db to drive two up-down adjacent pixels to display a same image, such that the resolution of the left visual images and the right visual images can be enlarged to the resolution of the display panel according to original scale. 
     Please refer to  FIG. 4 .  FIG. 4  is a diagram showing another embodiment of the display panel of the present invention driving pixels when displaying 3D images. As shown in  FIG. 4 , when the display panel  100  displays 3D images, the scan driver  110  can turn on main and secondary sub-pixels Pa, Pb of eight rows of the pixels P via eight of the first scan lines (such as Ga 1 -Ga 8 ) during a period (such as the period T 1 ) of the frame period, and turn on secondary sub-pixels Pb of the eight rows of the pixels P via eight of the second scan lines (such as Gb 1 -Gb 8 ) during another period (such as the period T 2 ) of the frame period. 
     According to the above arrangement, when the display panel  100  displays 3D images, time for turning on the pixels P can be quadrupled. Therefore, the display panel  100  of the present invention has enough time for charging, so as to display 3D images with higher resolution (such as resolution of 8K4K), and improve the crosstalk effect. 
     Please refer to  FIG. 5 .  FIG. 5  is a flowchart  500  showing a driving method of the display panel of the present invention. The flowchart of the driving method of the display panel of the present invention comprises the following steps: 
     Step  510 : Provide a display panel comprising a plurality of pixels, a plurality of first scan lines, a plurality of second scan lines, a plurality of first data lines, a plurality of second data lines, a scan driver, and data driver, wherein each of the plurality of pixels comprises a main sub-pixel and a secondary sub-pixel, each of the plurality of first scan lines is coupled to main and secondary sub-pixels of a row of pixels, each of the plurality of second scan lines is coupled to secondary sub-pixels of a row of pixels, each of the plurality of first data lines is coupled to main and secondary sub-pixels of (N+1)th and (N+2)th rows of pixels, each of the plurality of second data lines is coupled to main and secondary sub-pixels of (N+3)th and (N+4)th rows of pixels, N is a multiple of 4, and N≧0; 
     Step  520 : The scan driver turns on the main and secondary sub-pixels of the pixels via the plurality of first scan lines during a first period of a frame period; 
     Step  530 : The scan driver turns on the secondary sub-pixels of the pixels via the plurality of second scan lines during a second period of the frame period; and 
     Step  540 : The data driver outputs data signals to the turned on main and secondary sub-pixels via the first and second data lines. 
     Please refer to  FIG. 6 .  FIG. 6  is a diagram showing another embodiment of the display panel of the present invention driving pixels when displaying 3D images. As shown in  FIG. 6 , different from the above embodiments, in the display panel of  FIG. 6 , each of the first data lines Da is coupled to main and secondary sub-pixels of odd rows of pixels, and each of the plurality of second data lines Db is coupled to main and secondary sub-pixels of even rows of pixels. When the display panel displays 3D images, the scan driver  110  can turn on the main and secondary sub-pixels Pa, Pb of four rows of the pixels P via four (or multiple of 4) of the first scan lines (such as Ga 1 -Ga 4 ) during a period (such as the period T 1 ) of a frame period, and turn on the secondary sub-pixels Pb of the four rows of the pixels P via four (or multiple of 4) of the second scan lines (such as Gb 1 -Gb 4 ) during another period (such as the period T 3 ) of the frame period. 
     According to the above arrangement, since the scan driver  110  can turn on four rows of pixels P during a same period, and the data driver  120  can output data signals to two rows of pixels P via the first data lines Da, and output data signals to another two rows of pixels P via the second data lines during the same period, thus, time for turning on the pixels can be increased. Therefore, when the display panel  100  of the present invention is utilized to display 3D images, the data driver  120  has enough time to completely write the data signals into the pixels P. 
     Please refer to  FIG. 7 .  FIG. 7  is a flowchart  700  showing another driving method of the display panel of the present invention. The flowchart of another driving method of the display panel of the present invention comprises the following steps: 
     Step  710 : Provide a display panel comprising a plurality of pixels, a plurality of first scan lines, a plurality of second scan lines, a plurality of first data lines, a plurality of second data lines, a scan driver, and data driver, wherein each of the plurality of pixels comprises a main sub-pixel and a secondary sub-pixel, each of the plurality of first scan lines is coupled to main and secondary sub-pixels of a row of pixels, each of the plurality of second scan lines is coupled to secondary sub-pixels of a row of pixels, each of the plurality of first data lines is coupled to main and secondary sub-pixels of odd rows of pixels, each of the plurality of second data lines is coupled to main and secondary sub-pixels of even rows of pixels; 
     Step  720 : The scan driver turns on the main and secondary sub-pixels of the pixels via K of the first scan lines during a first period of a frame period, wherein K is a multiple of 4, and K≧0; 
     Step  730 : The scan driver turns on the secondary sub-pixels of the pixels via K of the second scan lines during a second period of the frame period; and 
     Step  740 : The data driver outputs data signals to the turned on main and secondary sub-pixels via the first and second data lines. 
     In contrast to the prior art, the display panel of the present invention can increase time for turning on the pixels when displaying high resolution images or 3D images. Therefore, the data driver of the present invention has enough time to completely write the data signals into the pixels, so as to improve image quality. 
     Those skilled in the art will readily observe that numerous modifications and alterations of the device and method may be made while retaining the teachings of the invention. Accordingly, the above disclosure should be construed as limited only by the metes and bounds of the appended claims.