Abstract:
An image display method of a half-source-driving (HSD) liquid crystal display (LCD) for mitigating the screen flickering effect caused by applying a frame rate control (FRC) algorithm in the LCD includes providing a first gate sequence corresponding to a pixel array in the LCD display. If a target gray level of the pixel array is an average value of a first gray level and a second gray level, write the first gray level to a plurality of sub-pixels of the pixel array being charged first according to the first gate sequence, and write the second gray level smaller than the first gray level to a plurality of sub-pixels of the pixel array being charged latter according to the first gate sequence.

Description:
BACKGROUND OF THE INVENTION 
       [0001]    1. Field of the Invention 
         [0002]    The present invention provides an image display method, and more particularly, image display method for a half-source driving liquid crystal display under various frame rate control algorithms. 
         [0003]    2. Description of the Prior Art 
         [0004]    A liquid crystal display (LCD) has been widely used and replaced a cathode ray tube (CRT) as the mainstream display device since it has several advantages, such as a minimal linear error, occupying small space, high mobility, little radiation, and power saving. LCDs are used to display images with various resolutions and sizes. They are used as computer monitors, cellphone panels, TV screens, etc. Nowadays, as the demand for higher resolution increases, LCDs with a half-source-driving (LCD-HSD) structure have been developed. The LCD-HSD structure provides LCDs smaller space and lower power consumption thereby increasing the resolution. 
         [0005]    Generally, the display panel of LCD includes a plurality of pixel arrays, a plurality of corresponding gate lines, and a plurality of corresponding data lines. Each pixel array includes a plurality of sub-pixels. Each sub-pixel corresponds to a different primary color, where the primary color can be defined by an RGB or CMYK color model. When the sub-pixel is enabled by the corresponding gate line, a corresponding gray level is written to the sub-pixel by the corresponding data line. As known, a different gray level yields different transmittances of the sub-pixel. When the plurality of sub-pixels on the LCD panel is presented various gray levels, the digital image with various colors and light intensities is shown. Generally, since each sub-pixel can present 256 gray levels (i.e., it is assumed that the LCD can display 256 gray levels, where the 256 gray levels are sorted by gray level 0 to gray level 255), a storage device is essential for saving the data of 256 gray levels in the LCD device and thus occupies the circuit space of the LCD. To reduce the circuit space of the storage device, only M gray levels are saved in the LCD device (i.e., M is a positive integer and 1&lt;M&lt;256). The residual 256-M gray levels can be presented by combining M gray levels based on an image display method called a frame rate control (FRC) algorithm. 
         [0006]    In the FRC algorithm, the main idea is to use two or more gray levels selecting from M gray levels and then respectively write these selected M gray levels to the different group of the sub-pixels of the pixel array with different quantities. This means that the sub-pixels of the pixel array are divided into two or more sets. The corresponding gray level is written to each set of sub-pixels in order to display a target gray level by the pixel array. Particularly, the target gray level indicates the expected value or average value of gray level of the pixel array. Thus, the FRC algorithm uses two or more sets of sub-pixels with respect to M gray levels for achieving the target gray level. 
         [0007]    Consider that the FRC algorithm is applied to an LCD-HSD. Since the sub-pixels of pixel array are charged sequentially, when two adjacent sub-pixels are written to the same gray levels, the sub-pixel being charged first is presented a gray level representing a lower light intensity than the sub-pixel being charged latter. This implies that when a predetermined gray level is written to the sub-pixel being charged first, the sub-pixel being charged first is presented a different gray level from a predetermined gray level, causing flicker and roll line effects on the display and thereby reducing the image display quality. 
       SUMMARY OF THE INVENTION 
       [0008]    According to an embodiment, the image display method for a half-source driving liquid crystal display is disclosed. The liquid crystal display includes a plurality of pixel arrays, a plurality of corresponding gate lines, and a plurality of corresponding data lines. Each pixel array includes a plurality of sub-pixels. Two adjacent sub-pixels are coupled to the same corresponding data line and are disposed at two different sides of the data line and are also coupled to two consecutive corresponding gate lines. The image display method includes providing a first gate sequence to a pixel array of the LCD. If a target gray level equals an average value of a first gray level and a second gray level, a first gray level is written to a plurality of sub-pixels of the pixel array being charged first according to the first gate sequence, and a second gray level is written to a plurality of sub-pixels of the pixel array being charged latter according to the first gate sequence. The first gray level is greater than the second gray level. 
         [0009]    According to an additional embodiment, another image display method for a half-source driving liquid crystal display is disclosed. The liquid crystal display includes a plurality of pixel arrays, a plurality of corresponding gate lines, and a plurality of corresponding data lines. Each pixel array includes a plurality of sub-pixels. Two adjacent sub-pixels are coupled to a same corresponding data line and are disposed at two different sides of the data line and are also coupled to two consecutive corresponding gate lines. The image display method includes providing a first gate sequence to the pixel array of the LCD. If a target gray level is closer to a second gray level than a first gray level, the first gray level is written to a first set of sub-pixels of the pixel array being charged first according to the first gate sequence, the second gray level is written to a second set of sub-pixels of the pixel array being charged first according to the first gate sequence, and the second gray level is written to a plurality of sub-pixels of the pixel array being charged latter according to the first gate sequence. The first gray level is greater than the second gray level. 
         [0010]    According to an additional embodiment, another image display method for a half-source driving liquid crystal display is disclosed. The liquid crystal display includes a plurality of pixel arrays, a plurality of corresponding gate lines, and a plurality of corresponding data lines. Each pixel array includes a plurality of sub-pixels. Two adjacent sub-pixels are coupled to a same corresponding data line and are disposed at two different sides of the data line and are also coupled to two consecutive corresponding gate lines. The image display method includes providing a first gate sequence to the pixel array of LCD. If a target gray level is closer to a first gray level than a second gray level, the first gray level is written into a plurality of sub-pixels of the pixel array being charged first according to the first gate sequence, the second gray level is written into a first set of sub-pixels of the pixel array being charged latter according to the first gate sequence, and the first gray level is written into a second set of sub-pixels of the pixel array being charged latter according to the first gate sequence. The first gray level is greater than the second gray level. 
         [0011]    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 
         [0012]      FIG. 1  is the structure of a half-source-driving LCD according to an embodiment of the present invention. 
           [0013]      FIG. 2  is the pixel array corresponding to the structure of the half-source-driving LCD illustrated in  FIG. 1 . 
       
    
    
     DETAILED DESCRIPTION 
       [0014]    Please refer to  FIG. 1  and  FIG. 2 .  FIG. 1  is the structure of a half-source-driving LCD according to an embodiment of the present invention.  FIG. 2  is the pixel array corresponding to the structure of the half-source-driving illustrated in  FIG. 1 . In  FIG. 1 , 16 sub-pixels are in the embodiment are considered as sub-pixel P 1  to sub-pixel P 16 . These sub-pixels are controlled by data line S 1 , data line S 2 , and gate lines G 1  to G 8 . Two adjacent sub-pixels coupled to the data line S 1  at different sides are respectively coupled to two consecutive gate lines. This means that the sub-pixels P 1  and P 2  are respectively coupled to the gate lines G 1  and G 2 . The sub-pixels P 3  and P 4  are respectively coupled to the gate lines G 3  and G 4 . The sub-pixels P 5  and P 6  are respectively coupled to the gate lines G 5  and G 6 . The sub-pixels P 7  and P 8  are respectively coupled to the gate lines G 7  and G 8 . Similarly, two adjacent sub-pixels coupled to the data line S 2  at different sides are respectively coupled to two consecutive gate lines. This means that the sub-pixels P 9  and P 10  are respectively coupled to the gate lines G 1  and G 2 . The sub-pixels P 11  and P 12  are respectively coupled to the gate lines G 3  and G 4 . The sub-pixels P 13  and P 14  are respectively coupled to the gate lines G 5  and G 6 . The sub-pixels P 15  and P 16  are respectively coupled to the gate lines G 7  and G 8 . The sub-pixel P 1  to sub-pixel P 16  are charged and enabled progressively according to a predetermined gate sequence. In this embodiment, the predetermined gate sequence is assumed to be 21345687. The sub-pixels coupled to the data line S 1  are enabled by the order of gate sequence, as sub-pixels P 2 , sub-pixels P 1 , sub-pixels P 3 , sub-pixels P 4 , sub-pixels P 5 , sub-pixels P 6 , sub-pixels P 8 , and sub-pixels P 7 . The sub-pixels coupled to the data line S 2  are enabled by the order of gate sequence, as sub-pixels P 10 , sub-pixels P 9 , sub-pixels P 11 , sub-pixels P 12 , sub-pixels P 13 , sub-pixels P 14 , sub-pixels P 16 , and sub-pixels P 15 . For presentation convenience, the sub-pixels being charged first denote that the sub-pixels are charged first according to the gate sequence. The sub-pixels being charged latter denote that the sub-pixels are charged latter according to the gate sequence. In this embodiment, the sub-pixels being charged first include sub-pixels P 2 , sub-pixels P 3 , sub-pixels P 5 , sub-pixels P 8 , sub-pixels P 10 , sub-pixels P 11 , sub-pixels P 13 , and sub-pixels P 16 . The sub-pixels being charged latter include sub-pixels P 1 , sub-pixels P 4 , sub-pixels P 6 , sub-pixels P 7 , sub-pixels P 9 , sub-pixels P 12 , sub-pixels P 14 , and sub-pixels P 15 . Note that the pixel array according to the embodiment of the present invention is considered as a 4 by 4 matrix. As shown in  FIG. 2 , the pixel array includes 16 sub-pixels as sub-pixel P 1  to sub-pixel P 16 . The order for enabling the sub-pixels of the pixel array according to the gate sequence is identical to the order for enabling the sub-pixels of half-source-driving structure in  FIG. 1 . 
         [0015]    The first embodiment for the image display method of half-source-driving liquid crystal display of the present invention is illustrated in the following. Here, three frame rate control (FRC) algorithms are considered to present the target gray level of the pixel array, named as FRC(01) algorithm, FRC(10) algorithm, and FRC(11) algorithm. Specifically, 4 sub-pixels carrying the first gray level and 12 sub-pixels carrying the second gray level of the pixel array are applied in FRC(01) algorithm to present the target gray level of the pixel array. 8 sub-pixels carrying the first gray level and 8 sub-pixels carrying the second gray level of the pixel array are applied in the FRC(10) algorithm to present the target gray level of the pixel array. 12 sub-pixels carrying the first gray level and 4 sub-pixels carrying the second gray level of the pixel array are applied in the FRC(11) algorithm to display the target gray level of the pixel array. In this embodiment, the first gray level is greater than the second gray level. The gate sequence of this embodiment is considered as 21345687. The detail expressions of the image display method are illustrated below. 
         [0016]    When the display uses the FRC(01) algorithm to present the target gray level of the pixel array, the sub-pixels of the pixel array being charged first are sub-pixel P 2 , sub-pixel P 3 , sub-pixel P 5 , sub-pixel P 8 , sub-pixel P 10 , sub-pixel P 11 , sub-pixel P 13 , and sub-pixel P 16 . The sub-pixels of the pixel array being charged latter are sub-pixel P 1 , sub-pixel P 4 , sub-pixel P 6 , sub-pixel P 7 , sub-pixel P 9 , sub-pixel P 12 , sub-pixel P 14 , and sub-pixel P 15 . The light intensity of the sub-pixels being charged first is lower than the light intensity of sub-pixels being charged latter. As known, reducing the contrast of the displayed gray level of the pixel array can mitigate the image flicker and roll line effect. By doing so, the plurality of sub-pixels being charged first is divided into two sets. These two sets of sub-pixels being charged first have the same quantities and can be formed by several combinations. For example, the first set of the sub-pixels being charged first can be located on the pixel array in sparse distribution or in dense distribution. When the first set of the sub-pixels being charged first is located on the pixel array in sparse distribution, the pixel array can be presented to a uniform contrast of gray level while resulting in satisfactory image display quality. In this case, the first set of the sub-pixels being charged first includes sub-pixel P 2 , sub-pixel P 3 , sub-pixel P 13 , and sub-pixel P 16 . The second set of the sub-pixels being charged first includes sub-pixel P 5 , sub-pixel P 8 , sub-pixel P 10 , and sub-pixel P 11 . The first gray level is written to the first set of the sub-pixels being charged first. The second gray level is written to the second set of the sub-pixels being charged first and all the sub-pixels being charged latter. The first set of the sub-pixels being charged first is presented a smaller gray level than the first gray level. The second set of the sub-pixels being charged first is presented a smaller gray level than the second gray level. This means that sub-pixel P 2 , sub-pixel P 3 , sub-pixel P 13 , and sub-pixel P 16  are presented a smaller gray level than the first gray level. Sub-pixel P 1 , sub-pixel P 4 , sub-pixel P 6 , sub-pixel P 7 , sub-pixel P 9 , sub-pixel P 12 , sub-pixel P 14 , and sub-pixel P 15  are presented the gray level equal to the first gray level. Sub-pixel P 5 , sub-pixel P 8 , sub-pixel P 10 , and sub-pixel P 11  are presented a smaller gray level than the second gray level. 
         [0017]    When the display uses the FRC(10) algorithm to present the target gray level of the pixel array, since the gate sequence is identical to the case of the FRC(01) algorithm in this embodiment, the plurality of sub-pixels being charged first and the plurality of sub-pixels being charged latter are identical to the case of FRC(01) in this embodiment. The light intensity of the plurality of sub-pixels being charged first is lower than the light intensity of the plurality of sub-pixels being charged latter. As known, reducing the contrast of the presented gray level of the pixel array can mitigate the image flicker and roll line effect. By doing so, the first gray level is written to 8 sub-pixels being charged first and the second gray level is written to 8 sub-pixels being charged latter. The sub-pixels being charged first are presented to smaller gray level than the first gray level. This means that sub-pixel P 2 , sub-pixel P 3 , sub-pixel P 5 , sub-pixel P 8 , sub-pixel P 10 , sub-pixel P 11 , sub-pixel P 13 , and sub-pixel P 16  are presented to a smaller gray level than the first gray level. Sub-pixel P 1 , sub-pixel P 4 , sub-pixel P 6 , sub-pixel P 7 , sub-pixel P 9 , sub-pixel P 12 , sub-pixel P 14 , and sub-pixel P 15  are presented to the gray level equal to the second gray level. 
         [0018]    When the display uses the FRC(11) algorithm to present the target gray level of the pixel array, since the gate sequence in this embodiment is identical to the case of FRC(01) algorithm in this embodiment, the plurality of sub-pixels of the pixel array being charged first and the plurality of sub-pixels of the pixel array being charged latter are identical to the case of FRC(01) algorithm in this embodiment, wherein the sub-pixels being charged first suffer from the effect of low light intensity. To mitigate the image flicker and roll line effect by reducing the contrast of the presented gray level of the pixel array, the plurality of sub-pixels being charged latter are divided into two sets. These two sets of sub-pixels being charged latter have the same quantities and can be formed by several combinations. For example, the first set of the sub-pixels being charged latter can be located on the pixel array in sparse distribution or in dense distribution. When the first set of the sub-pixels being charged latter is located on the pixel array in sparse distribution, the pixel array can be presented to a uniform contrast of gray level while resulting in satisfactory image display quality. In this case, the first set of the sub-pixels being charged latter includes sub-pixel P 6 , sub-pixel P 7 , sub-pixel P 9 , and sub-pixel P 12 . The second set of the sub-pixels being charged latter includes sub-pixel P 1 , sub-pixel P 4 , sub-pixel P 14 , and sub-pixel P 15 . The second gray level is written to the first set of the sub-pixels being charged latter. The first gray level is written to the second set of the sub-pixels being charged latter and all the sub-pixels being charged first. The plurality of sub-pixels being charged first is presented to smaller gray level than the first gray level. This means that sub-pixel P 2 , sub-pixel P 3 , sub-pixel P 5 , sub-pixel P 8 , sub-pixel P 10 , sub-pixel P 11 , sub-pixel P 13 , and sub-pixel P 16  are presented to smaller gray level than the first gray level. Sub-pixel P 1 , sub-pixel P 4 , sub-pixel P 14 , and sub-pixel P 15  are presented to the gray level equal to the first gray level. Sub-pixel P 6 , sub-pixel P 7 , sub-pixel P 9 , and sub-pixel P 12  are presented to the gray level equal to the second gray level. 
         [0019]    The second embodiment for the image display method of the half-source driving liquid crystal display of the present invention is illustrated in the following. Different from the first embodiment by enabling the sub-pixels according to a single gate sequence and writing the corresponding gray level into each sub-pixel, the image display method in the second embodiment can avoid the lifetime reduction problem in the first embodiment. As known, when the same gray level is repeatedly written to the same sub-pixel, the lifetime of the sub-pixel is reduced. For example, in the first embodiment, the first gray level is repeatedly written to sub-pixel P 2  and thus reduces the lifetime of sub-pixel P 2 . In the second embodiment, two different gate sequences are alternatively used during the timing interval of consecutive four image frames. Here, four image frames are indicated as the first image frame, the second image frame, the third image frame, and the fourth image frame. Two different gate sequences are indicated as the first gate sequence and the second gate sequence. In this embodiment, the first gate sequence is defined as 21345687. The second sequence is defined as 12436578. Consider that the FRC(01), FRC(10), and FRC(11) algorithms are used to present the target gray level of the pixel array. In the second embodiment, the first set of the sub-pixels being charged first, the second set of the sub-pixels being charged first, the first set of the sub-pixels being charged latter, and the second set of the sub-pixels being charged latter according to the first gate sequence and the second gate sequence can be formed by several combinations. For presentation convenience, a specific combination is used in the second embodiments to present the target gray level of the pixel array, as follows. 
         [0020]    When the display uses the FRC(01) algorithm to present the target gray level of the pixel array, in the first image frame, the method of the first gray level and the second gray level written to the plurality of sub-pixels of the pixel array according to the first gate sequence is identical to the case of the FRC(01) algorithm in the first embodiment. In the third image frame, the method of the first gray level and the second gray level written to the plurality of sub-pixels of the pixel array according to the first gate sequence is similar to the case of the first image frame in this embodiment. The difference is that the first set and the second set of the sub-pixels being charged first are different from the case of the first image frame in this embodiment. In the third image frame, the first set of the sub-pixels being charged first includes sub-pixel P 5 , sub-pixel P 8 , sub-pixel P 10 , and sub-pixel P 11 . The second set of the sub-pixels being charged first includes sub-pixel P 2 , sub-pixel P 3 , sub-pixel P 13 , and sub-pixel P 16 . In the second and the fourth image frames, since the odd-ordered elements of the second gate sequence are identical to the even-ordered elements of the first gate sequence and the even-ordered elements of the second gate sequence are identical to the odd-ordered elements of the first gate sequence, the sub-pixels being charged first of the pixel array in the first and the third image frames are respectively identical to the sub-pixels being charged latter in the second and the fourth image frames. In the second and the fourth image frames, the method of the first gray level and the second gray level written to the plurality of sub-pixels according to the second gate sequence is to write the first gray level to the first set of the sub-pixels being charged first and write the second gray level to the second set of the sub-pixels being charged first and all the sub-pixels being charged latter. The first set and the second set of the sub-pixels being charged first in the second image frame and the fourth image frame are different. In the second image frame, the first set of the sub-pixels being charged first includes sub-pixel P 1 , sub-pixel P 6 , sub-pixel P 12 , and sub-pixel P 15 . The second set of the sub-pixels being charged first includes sub-pixel P 4 , sub-pixel P 7 , sub-pixel P 8 , and sub-pixel P 13 . In the fourth image frame, the first set of the sub-pixels being charged first includes sub-pixel P 4 , sub-pixel P 7 , sub-pixel P 8 , and sub-pixel P 13 . The second set of the sub-pixels being charged first includes sub-pixel P 1 , sub-pixel P 6 , sub-pixel P 12 , and sub-pixel P 15 . According to the image display method in this embodiment, during the timing interval of consecutive four image frames, the first gray level is written to each sub-pixel during the timing interval of one image frame. The second gray level is written to each sub-pixel during the timing interval of three image frames. 
         [0021]    When the display uses the FRC(10) algorithm to present the target gray level of the pixel array, in the first and the third image frames, the method of the first gray level and the second gray level written to the plurality of sub-pixels of the pixel array according to the first gate sequence is identical to the case of the FRC(10) algorithm in the first embodiment. In the second and the fourth image frames, since the odd-ordered elements of the second gate sequence are identical to the even-ordered elements of the first gate sequence and the even-ordered elements of the second gate sequence are identical to the odd-ordered elements of the first gate sequence, the sub-pixels being charged first in the first and the third image frames are respectively identical to the sub-pixels being charged latter in the second and the fourth image frames. The sub-pixels being charged latter of the pixel array in the first and the third image frames are respectively identical to the sub-pixels being charged first in the second and the fourth image frames. In the second and the fourth image frames, the method of the first gray level and the second gray level written to the plurality of sub-pixels according to the second gate sequence is to write the first gray level to the sub-pixels being charged first and write the second gray level to the sub-pixels being charged latter. According to the image display method in this embodiment, during the timing interval of consecutive four image frames, the first gray level is written to each sub-pixel during the timing interval of two image frames. The second gray level is written to each sub-pixel during the timing interval of two image frames. 
         [0022]    When the display uses the FRC(11) algorithm to present the target gray level of the pixel array, in the third image frame, the method of the first gray level and the second gray level written to the plurality of sub-pixels of the pixel array according to the first gate sequence is identical to the case of FRC(11) in the first embodiment. In the first image frame, the method of the first gray level and the second gray level written to the plurality of sub-pixels of the pixel array according to the first gate sequence is similar to the case of the third image frame in this embodiment. The difference is that the first set and the second set of the sub-pixels being charged latter are different from the case of the third image frame in this embodiment. In the first image frame, the first set of the sub-pixels being charged latter includes sub-pixel P 1 , sub-pixel P 4 , sub-pixel P 14 , and sub-pixel P 15 . The second set of the sub-pixels being charged latter includes sub-pixel P 6 , sub-pixel P 7 , sub-pixel P 9 , and sub-pixel P 12 . In the second and the fourth image frames, since the odd-ordered elements of the second gate sequence are identical to the even-ordered elements of the first gate sequence and the even-ordered elements of the second gate sequence are identical to the odd-ordered elements of the first gate sequence, the sub-pixels being charged first in the first and the third image frames are respectively identical to the sub-pixels being charged latter in the second and the fourth image frames. The sub-pixels being charged latter in the first and the third image frames are respectively identical to the sub-pixels being charged first in the second and the fourth image frames. In the second and the fourth image frames, the method of the first gray level and the second gray level written to the plurality of sub-pixels according to the second gate sequence is to write the second gray level to the first set of the sub-pixels being charged latter and write the first gray level to the second set of the sub-pixels being charged latter and all the sub-pixels being charged first. The first set and the second set of the sub-pixels being charged latter in the second image frame and the fourth image frame are different. In the second image frame, the first set of the sub-pixels being charged latter includes sub-pixel P 3 , sub-pixel P 8 , sub-pixel P 10 , and sub-pixel P 13 . The second set of the sub-pixels being charged latter includes sub-pixel P 2 , sub-pixel P 5 , sub-pixel P 11 , and sub-pixel P 16 . In the fourth image frame, the first set of the sub-pixels being charged latter includes sub-pixel P 2 , sub-pixel P 5 , sub-pixel P 11 , and sub-pixel P 16 . The second set of the sub-pixels being charged latter includes sub-pixel P 3 , sub-pixel P 8 , sub-pixel P 10 , and sub-pixel P 13 . According to the image display method in this embodiment, during the timing interval of consecutive four image frames, the first gray level is written to each sub-pixel during the timing interval of three image frames. The second gray level is written to each sub-pixel during the timing interval of one image frame. 
         [0023]    The third embodiment for the image display method of the half-source driving liquid crystal display of the present invention is illustrated in the following. Different from the aforementioned second embodiment, four different gate sequences are alternatively used during the timing interval of consecutive four image frames in this embodiment. Four different gate sequences are indicated as the first gate sequence, the second gate sequence, the third gate sequence, and the fourth gate sequence. In this embodiment, the first gate sequence is defined as 21345687. The second sequence is defined as 12436578. The third gate sequence is defined as 21435687. The fourth gate sequence is defined as 12346578. Consider that FRC(01), FRC(10), and FRC(11) algorithms are used to present the target gray level of the pixel array. In the third embodiment, the first set of the sub-pixels being charged first, the second set of the sub-pixels being charged first, the first set of the sub-pixels being charged latter, and the second set of the sub-pixels being charged latter according to the first gate sequence and the second gate sequence can be formed by several combinations. For presentation convenience, a specific combination is used in the third embodiment to present the target gray level of the pixel array, as follows. 
         [0024]    When the display uses the FRC(01) algorithm to present the target gray level of the pixel array, in the first and the second image frames, the method of the first gray level and the second gray level written to the plurality of sub-pixels of the pixel array according to the first gate sequence(in the first image frame) and the second gate sequence(in the second image frame) is identical to the case of the FRC(01) algorithm in the first and the second image frames of the second embodiment. Specifically, the methods of the first gray level and the second gray level written to the plurality of sub-pixels in the third and the fourth image frames are similar. The common idea is to write the first gray level to the first set of the sub-pixels being charged first and write the second gray level to the second set of the sub-pixels being charged first and all the sub-pixels being charged latter. However, since the gate sequences corresponding to the third and the fourth image frames are different, the plurality of sub-pixels being charged first and the plurality of sub-pixels being charged latter are different. In the third image frame, according to the third gate sequence, the sub-pixels being charged first include sub-pixel P 2 , sub-pixel P 4 , sub-pixel P 15 , sub-pixel P 8 , sub-pixel P 10 , sub-pixel P 12 , sub-pixel P 13 , and sub-pixel P 16 . The residual sub-pixels of the pixel array are the sub-pixels being charged latter. These sub-pixels being charged first are further divided into the first set of the sub-pixels being charged first and the second set of the sub-pixels being charged first. In the third image frame, the first set of the sub-pixels being charged first includes sub-pixel P 4 , sub-pixel P 5 , sub-pixel P 8 , and sub-pixel P 10 . The second set of the sub-pixels being charged first includes sub-pixel P 2 , sub-pixel P 12 , sub-pixel P 13 , and sub-pixel P 16 . In the fourth image frame, since the odd-ordered elements of the fourth gate sequence are identical to the even-ordered elements of the third gate sequence and the even-ordered elements of the fourth gate sequence are identical to the odd-ordered elements of the third gate sequence, the sub-pixels being charged first of the pixel array in the third image frame are identical to the sub-pixels being charged latter of the pixel array in the fourth image frame. The sub-pixels being charged latter of the pixel array in the third image frame are identical to the sub-pixels being charged first of the pixel array in the fourth image frame. Further, in the fourth image frame, the first set of the sub-pixels being charged first includes sub-pixel P 7 , sub-pixel P 8 , sub-pixel P 10 , and sub-pixel P 13 . The second set of the sub-pixels being charged first includes sub-pixel P 1 , sub-pixel P 3 , sub-pixel P 6 , and sub-pixel P 14 . According to the image display method in this embodiment, during the timing interval of consecutive four image frames, the first gray level is written to each sub-pixel during the timing interval of one image frame. The second gray level is written to each sub-pixel during the timing interval of three image frames. 
         [0025]    When the display uses the FRC(10) algorithm to present the target gray level of the pixel array, in the third and the fourth image frames, the first gray level is written to the sub-pixels being charged first and the second gray level is written to the sub-pixels being charged latter. Specifically, since the gate sequences corresponding to the third and the fourth image frames are different, the plurality of sub-pixels being charged first and the plurality of sub-pixels being charged latter are different. In the third image frame, according to the third gate sequence, the sub-pixels of the pixel array being charged first and the sub-pixels of the pixel array being charged latter are identical to the case of the FRC(01) algorithm in the third image frame of this embodiment. In the fourth image frame, according to the fourth gate sequence, the sub-pixels of the pixel array being charged first and the sub-pixels of the pixel array being charged latter are identical to the case of the FRC(01) algorithm in the fourth image frame of this embodiment. According to the image display method in this embodiment, during the timing interval of consecutive four image frames, the first gray level is written to each sub-pixel during the timing interval of two image frames. The second gray level is written to each sub-pixel during the timing interval of two image frames. 
         [0026]    When the display uses the FRC(11) algorithm to present the target gray level of the pixel array, in the first and the second image frames, the method of the first gray level and the second gray level written to the plurality of sub-pixels of the pixel array according to the first gate sequence(in the first image frame) and the second gate sequence (in the second image frame) is identical to the case of the FRC(11) algorithm in the first and the second image frames of the second embodiment. Specifically, the methods of the first gray level and the second gray level written to the plurality of sub-pixels in the third and the fourth image frames are similar. The common idea is to write the second gray level to the first set of the sub-pixels being charged latter and write the first gray level to the second set of the sub-pixels being charged latter and all the sub-pixels being charged first. However, since the gate sequences corresponding to the third and the fourth image frames are different, the plurality of sub-pixels being charged first and the plurality of sub-pixels being charged latter are different. In the third image frame, according to the third gate sequence, the sub-pixels of the pixel array being charged first and the sub-pixels of the pixel array being charged latter are identical to the case of the FRC(01) algorithm in the third image frame of this embodiment. In the fourth image frame, according to the fourth gate sequence, the sub-pixels of the pixel array being charged first and the sub-pixels of the pixel array being charged latter are identical to the case of the FRC(01) algorithm in the fourth image frame of this embodiment. In the third image frame, the first set of the sub-pixels being charged latter includes sub-pixel P 6 , sub-pixel P 7 , sub-pixel P 9 , and sub-pixel P 11 . The second set of the sub-pixels being charged latter includes sub-pixel P 1 , sub-pixel P 3 , sub-pixel P 14 , and sub-pixel P 15 . In the fourth image frame, the first set of the sub-pixels being charged latter includes sub-pixel P 2 , sub-pixel P 5 , sub-pixel P 12 , and sub-pixel P 16 . The second set of the sub-pixels being charged latter includes sub-pixel P 4 , sub-pixel P 8 , sub-pixel P 10 , and sub-pixel P 13 . According to the image display method in this embodiment, during the timing interval of consecutive four image frames, the first gray level is written to each sub-pixel during the timing interval of three image frames. The second gray level is written to each sub-pixel during the timing interval of one image frame. 
         [0027]    In the present invention, an image display method of half-source driving liquid crystal display is proposed. The main idea is to use the property that the sub-pixels of the pixel array being charged first are presented to lower light intensity than the sub-pixels of the pixel array being charged latter. It is assumed that the first gray level is greater than the second gray level. When the display uses various frame rate control (FRC) algorithms to present the target gray level of the pixel array, the sub-pixels assigned to the first gray level are located on the sub-pixels being charged first to present the light intensity smaller than the first gray level. The sub-pixels assigned to the second gray level are located on the sub-pixels being charged latter to present the light intensity equal to the second gray level. By doing so, the contrast of the presented gray level of the pixel array for various FRC algorithms can be reduced to mitigate the flicker and roll line effect on the display. 
         [0028]    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.