Abstract:
A display apparatus and driving method thereof are provided. The driving method is adapted for driving a backlight module and a display panel thereon, and includes at least the following steps. Firstly, a backlight data and a display data are outputted according to a color distribution of an expected image. Afterwards, a light-emitting pattern whose color distribution corresponds to the color distribution of the expected image of the backlight module is determined according to the backlight data. Besides, a display pattern of the display panel is determined according to the display data. The expected image is displayed through the light-emitting pattern and the display pattern.

Description:
CROSS-REFERENCE TO RELATED APPLICATION 
       [0001]    This application claims the priority benefit of Taiwan application serial no. 98110008, filed on Mar. 26, 2009. The entirety of the above-mentioned patent application is hereby incorporated by reference herein and made a part of specification. 
       BACKGROUND OF THE INVENTION 
       [0002]    1. Field of the Invention 
         [0003]    The present invention relates to an apparatus and a driving method thereof, and more particularly to a display apparatus and a driving method thereof. 
         [0004]    2. Description of Related Art 
         [0005]    With development of optoelectronic and semiconductor techniques, display apparatuses are developed accordingly, in which liquid crystal display (LCD) apparatuses become popular in the market due to features of high space utilization efficiency, free of radiation, and low electromagnetic interference etc. 
         [0006]    Since the display panel in the LCD apparatus has no luminescent function itself, the backlight module is usually disposed beneath the display panel for providing a planar light source required by the display panel. The display panel determines the transmittance of the planar light source of the backlight module through the liquid crystal (LC) molecules in the LC layer for the LCD apparatus to display images to the users. 
         [0007]    However, when the LC molecules in the LC layer of the display panel are arranged poorly, light leakage occurs in dark images, thereby reducing the contrast ratio and color saturation of the display image. To solve the aforementioned problem, an LCD apparatus with a local controlled backlight module is provided. 
         [0008]    In light of the foregoing, the light-emitting unit in the local controlled backlight module emits light based on the profile of the expected image. For example, the expected image is a scene of an evening sky along with a moon. Consequently, the light-emitting units corresponding to the moon provide white light source and the light-emitting units corresponding to the evening sky do not provide any light source. In other words, the light-emitting pattern provided by the light-emitting units is similar to the expected image. 
         [0009]    Through the design aforementioned, the contrast ratio of the moon (white) and the evening sky (black) is enhanced. However, such local controlled backlight module merely improves the contrast ratio of the display image, and does not enhance the color saturation of the display image. 
       SUMMARY OF THE INVENTION 
       [0010]    The present invention provides a display apparatus, where a display image thereof has high color saturation and contrast ratio. 
         [0011]    The present invention provides another display apparatus, which has the advantage of low power consumption. 
         [0012]    The present invention further provides a driving method adapted for driving a display apparatus and configured to enhance the color saturation of a display image. 
         [0013]    The present invention provides a driving method adapted for driving a backlight module and a display panel thereon. The driving method includes the following steps. Firstly, a backlight data and a display data are outputted according to a color distribution of an expected image. Next, a light-emitting pattern of the backlight module is determined according to the backlight data. Here, a color distribution of the light-emitting pattern corresponds to the color distribution of the expected image. On the other hand, a display pattern of the display panel is determined according to the display data. 
         [0014]    The present invention provides a display apparatus including a backlight module, a display panel, and a controller. The display panel is disposed on the backlight module and the controller is coupled to the backlight module and the display panel. Moreover, the controller outputs a backlight data to the backlight module according to a color distribution of an expected image and determines a light-emitting pattern of the backlight module according to the backlight data. A color distribution of the light-emitting pattern corresponds to the color distribution of the expected image. On the other hand, the controller outputs a display data to the display panel according to the color distribution of the expected image and determines a display pattern of the display panel according to the display data. 
         [0015]    According to an embodiment of the driving method and the display apparatus provided in the present invention, the controller generates and outputs the backlight data according to the color distribution of the expected image. The controller further generates and outputs the display data according to the color distribution of the expected image and the backlight data. 
         [0016]    According to an embodiment of the display apparatus in the present invention, the display panel includes a passive LCD panel. 
         [0017]    According to an embodiment of the driving method and the display apparatus in the present invention, the light-emitting pattern has a first color region, a second color region, a third color region, and a fourth color region. The color distributions of the first color region, the second color region, the third color region, and the fourth color region correspond to the color distribution of the expected image. In one embodiment, the display data has a first sub-display data recording a specific gray-scale value, a second sub-display data recording a first color gray-scale value, a third sub-display data recording a second color gray-scale value, and a fourth sub-display data recording a third color gray-scale value. Moreover, the display pattern has a first gray-scale pattern, a second gray-scale pattern, a third gray-scale pattern, and a fourth gray-scale pattern. According to an embodiment, a first initial color gray-scale value, a second initial color gray-scale value, and a third initial color gray-scale value are recorded in the display data. The specific gray-scale value is the minimum value of the first initial color gray-scale value, the second initial color gray-scale value, and the third initial color gray-scale value. In addition, the first color gray-scale value is the difference between the first initial color gray-scale value and the specific gray-scale value. The second color gray-scale value is the difference between the second initial color gray-scale value and the specific gray-scale value. Additionally, the third color gray-scale value is the difference between the third initial color gray-scale value and the specific gray-scale value. 
         [0018]    According to an embodiment of the driving method and the display apparatus of the present invention, the controller determines the first gray-scale pattern, the second gray-scale pattern, the third gray-scale pattern, and the fourth gray-scale pattern according to the first sub-display data, the second sub-display data, the third sub-display data, and the fourth sub-display data respectively, so as to determine the display pattern of the display panel aforementioned. 
         [0019]    According to an embodiment of the driving method and the display apparatus of the present invention, the expected image has a first sub-image, a second sub-image, a third sub-image, and a fourth sub-image. The step of displaying the expected image includes the following sub-steps. Firstly, the display apparatus displays the first sub-image according to the first color region and the first gray-scale pattern. Then, the display apparatus displays the second sub-image according to the second color region and the second gray-scale pattern. Next, the display apparatus displays the third sub-image according to the third color region and the third gray-scale pattern. Afterwards, the display apparatus displays the fourth sub-image according to the fourth color region and the fourth gray-scale pattern. In other words, the first sub-image, the second sub-image, the third sub-image, and the fourth sub-image are displayed sequentially. In one embodiment, the color of the first color region includes red, green, and blue, the second color region is a red region, the third color region is a green region, and the fourth color region is a blue region. 
         [0020]    According to an embodiment of the display apparatus of the present invention, the backlight module includes a plurality of first color light-emitting units, a plurality of second color light-emitting units, and a plurality of third color light-emitting units. Here, at least a portion of the first color light-emitting units, at least a portion of the second color light-emitting units, and at least a portion of the third color light-emitting units provide the first color region. Moreover, at least a portion of the first color light-emitting units provides the second color region, at least a portion of the second color light-emitting units provides the third color region, and at least a portion of the third color light-emitting units provides the fourth color region. 
         [0021]    According to an embodiment of the driving method and the display apparatus in the present invention, the light-emitting pattern has a first color region, a second color region, and a third color region. The color distributions of the first color region, the second color region, and the third color region correspond to the color distribution of the expected image. In one embodiment, the display data has a first sub-display data recording a first color gray-scale value, a second sub-display data recording a second color gray-scale value, and a third sub-display data recording a third color gray-scale value. In addition, the display pattern has a first gray-scale pattern, a second gray-scale pattern, and a third gray-scale pattern. 
         [0022]    According to an embodiment of the driving method and the display apparatus of the present invention, the controller determines the first gray-scale pattern, the second gray-scale pattern, and the third gray-scale pattern according to the first sub-display data, the second sub-display data, and the third sub-display data respectively, so as to determine the display pattern of the display panel aforementioned. 
         [0023]    According to an embodiment of the driving method and the display apparatus of the present invention, the expected image has a first sub-image, a second sub-image, and a third sub-image. The step of displaying the expected image includes the following sub-steps. Firstly, the display apparatus displays the first sub-image according to the first color region and the first gray-scale pattern. Next, the display apparatus displays the second sub-image according to the second color region and the second gray-scale pattern. Thereafter, the display apparatus displays the third sub-image according to the third color region and the third gray-scale pattern. In other words, the first sub-image, the second sub-image, and the third sub-image are displayed sequentially. 
         [0024]    According to an embodiment of the display apparatus of the present invention, the backlight module includes a plurality of first color light-emitting units, a plurality of second color light-emitting units, and a plurality of third color light-emitting units. Moreover, at least a portion of the first color light-emitting units provides the first color region, at least a portion of the second color light-emitting units provides the second color region, and at least a portion of the third color light-emitting units provides the third color region. 
         [0025]    According to an embodiment of the driving method and the display apparatus of the present invention, the light-emitting pattern and the display pattern are a multicolored region and a multicolored pattern respectively. A color distribution of the multicolored region and a color distribution of the multicolored pattern correspond to the color distribution of the expected image respectively. 
         [0026]    According to an embodiment of the display apparatus of the present invention, the backlight module includes a plurality of first color light-emitting units, a plurality of second color light-emitting units, and a plurality of third color light-emitting units. Here, at least a portion of the first color light-emitting units, at least a portion of the second color light-emitting units, and at least a portion of the third color light-emitting units provide the multicolored region. Furthermore, the display panel includes a color filter. 
         [0027]    In light of the foregoing, the backlight module in the display apparatus of the present invention provides the light-emitting pattern that corresponds to the color distribution of the expected image. Therefore, not only the power consumption of the backlight module is reduced, but the color saturation of the display image of the display apparatus is also enhanced. Hence, the contrast ratio and the color saturation are greatly enhanced in the display image of the display apparatus applying the driving method of the present invention. 
         [0028]    In order to make the aforementioned and other features and advantages of the present invention more comprehensible, several embodiments accompanied with figures are described in detail below. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0029]    The accompanying drawings are included to provide a further understanding of the invention, and are incorporated in and constitute a part of this specification. The drawings illustrate embodiments of the invention and, together with the description, serve to explain the principles of the invention. 
           [0030]      FIG. 1  is a schematic view illustrating a framework of a display apparatus according to an embodiment of the present invention. 
           [0031]      FIG. 2  is a partial cross-sectional view of a display apparatus according to an embodiment of the present invention. 
           [0032]      FIG. 3  is a flow chart illustrating a driving method according to an embodiment of the present invention. 
           [0033]      FIG. 4A  is a schematic diagram of an expected image, a backlight data, and a display data according to an embodiment of the present invention. 
           [0034]      FIG. 4B  is a schematic diagram of a backlight data and a light-emitting pattern according to a first embodiment of the present invention. 
           [0035]      FIG. 4C  is a schematic diagram of a display data and a display pattern according to the first embodiment of the present invention. 
           [0036]      FIG. 5A  is a schematic diagram of a backlight data and a light-emitting pattern according to a second embodiment of the present invention. 
           [0037]      FIG. 5B  is a schematic diagram of a display data and a display pattern according to the second embodiment of the present invention. 
           [0038]      FIG. 6  is a partial cross-sectional view of a display panel according to a third embodiment of the present invention. 
           [0039]      FIG. 7A  is a schematic diagram of a backlight data and a light-emitting pattern according to the third embodiment of the present invention. 
           [0040]      FIG. 7B  is a schematic diagram of a display data and a display pattern according to the third embodiment of the present invention. 
       
    
    
     DESCRIPTION OF EMBODIMENTS 
     First Embodiment 
       [0041]      FIG. 1  is a schematic view illustrating a framework of a display apparatus according to an embodiment of the present invention.  FIG. 2  is a partial cross-sectional view of a display apparatus according to an embodiment of the present invention. Here,  FIG. 2  merely shows a backlight module  110  and a display panel  120 . Referring to  FIG. 1  and  FIG. 2  simultaneously, a display apparatus  100  of the present embodiment includes a backlight module  110 , a display panel  120 , and a controller  130 . The controller  130  is coupled to the backlight module  110  and the display panel  120 . The display panel  120  is disposed on the backlight module  110 . Moreover, the display panel  120  is assembled by clamping an LC layer  126  between two substrates  122  and  124 . Obviously, the display apparatus  100  of the present embodiment can further include other components, and  FIG. 1  and  FIG. 2  omit the other components mainly to facilitate the illustration of the following embodiment. 
         [0042]    In the present embodiment, the display panel  120  is a passive LCD panel, for example. The substrates  122 ,  124  and the LC layer  126  are respectively a passive array substrate, an opposite substrate, and a super twisted nematic liquid crystal (STN LC) layer, for instance. However, in other embodiments, the display panel  120  can also be an active LCD panel or display panels of other types. In other words, the present invention does not limit the type of the display panel  120 . 
         [0043]    On the other hand, the backlight module  110  of the present embodiment is, for example, a local controlled backlight module. The local controlled backlight module noted here is the backlight module  110  that provides a multicolored light-emitting pattern (described in the following). Here, the color distribution of this multicolored light-emitting pattern corresponds to the color distribution of the expected image. That is, the backlight module  110  provides a multicolored light-emitting pattern which is similar to the expected image. Moreover, the light-emitting intensity of the backlight module  110  alters with the brightness of the expected image. Thus, not only the overall gray-scale number of the display image of the display apparatus  100  is increased, but the power consumption of the display apparatus  100  is also reduced. 
         [0044]    As aforementioned, the backlight module  110  of the present embodiment includes a plurality of first color light-emitting units  110 R, a plurality of second color light-emitting units  110 G, and a plurality of third color light-emitting units  110 B to further provide various light-emitting patterns, such as red-light pattern, green-light pattern, blue-light pattern, multicolored-light pattern, and the like. In the following embodiment, the first, the second, and the third color light-emitting units  110 R,  110 G, and  110 B are assumed to be red, green, and blue light-emitting units respectively. Furthermore, these red, green, and blue light-emitting units are arranged alternately as an array. 
         [0045]      FIG. 3  is a flow chart illustrating a driving method according to an embodiment of the present invention. Referring to  FIG. 1 ,  FIG. 2 , and  FIG. 3  simultaneously, firstly, the controller  130  outputs a backlight data and a display data according to the color distribution of an expected image  400  (step S 301 ). 
         [0046]    It should be noted that the aforementioned display data is generated from the color distribution of the expected image and the backlight data. In details, the controller  130  of the present embodiment generates the backlight data according to the color distribution of the expected image and then generates the display data according to the color distribution of the expected image and this backlight data. 
         [0047]    To give an example, as shown in  FIG. 4A , the expected image  400  is assumed to include red flowers E R1  and E R2 , a green mountains E G , a blue river E B , a gray cloud E Gray , and a black evening sky E Black . The controller  130  of the present embodiment generates a backlight data  410  according to the red flowers E R1  and E R2 , the green mountains E G , the blue river E B , the gray cloud E Gray , and the black evening sky E Black . Moreover, the color distribution recorded in the backlight data  410  corresponds to the color distribution of the expected image  400 . For example, red flowers E R1 , E R2 , B R1 , and B R2  are located at the left bottom corner of the expected image  400  and the backlight data  410  respectively. Green mountains E G  and B G  are located in the middle of the expected image  400  and the backlight data  410  respectively. Blue rivers E B  and B B  are located at the right bottom corner of the expected image  400  and the backlight data  410  respectively. Gray clouds E Gray  and B Gray  are located at the left top corner of the expected image  400  and the backlight data  410  respectively. Finally, black evening skies E Black  and B Black  are respectively located at the remaining locations of the expected image  400  and the backlight data  410 . 
         [0048]    Subsequently, the controller  130  generates a display data  420  according to the backlight data  410  and the expected image  400 . In other words, red flowers D R1  and D R2 , a green mountains D G , a blue river D B , a gray cloud D Gray , and a black evening sky D Black  that are recorded in the display data  420  are generated according to the red flowers B R1  and B R2 , the green mountains B G , the blue river B B , the gray cloud B Gray , and the black evening sky B Black  that are recorded in the backlight data  410  and the red flowers E R1  and E R2 , the green mountains E G , the blue river E B , the gray cloud E Gray , and the black evening sky E Black  shown in the expected image  400 . 
         [0049]    In the present embodiment, the controller  130  outputs the backlight data  410  and the display data  420  to the backlight module  110  and the display panel  120  respectively. However, in the following process, the controller  130  further determines a light-emitting pattern (described in the following) and a display pattern (described in the following) according to the backlight data  410  and the display data  420  respectively. As a result, the representation of the expected image  400  depends on the sampling of the backlight data  410  and the display data  420 . 
         [0050]    Take the red flowers E R1 , B R1 , and D R1  in the expected image  400 , the backlight data  410 , and the display data  420  as an example, in one embodiment, the accumulated effect of the light-emitting pattern and the display pattern respectively generated with the red flower B R1  and the red flower D R1  in the subsequent process substantially equals to the representation of the red flower E R1 . For example, the intensity of the light-emitting pattern generated with B R1  together with the intensity of the display pattern generated with D R1  substantially equal to the intensity of E R1 . The relationship between other images (i.e. E R2 , E G , E B , E Gray , E Black , and the like) in the expected image  400  and other information (i.e. B R2 , B G , B B , B Gray , B Black , and D R2 , D G , D B , D Gray , D Black  and the like) recorded in the backlight data  410  and the display data  420  is inferred likewise. 
         [0051]    As the color distribution recorded in the backlight data  410  corresponds to the color distribution of the expected image  400 , the controller  130  of the present embodiment determines a light-emitting pattern  412  of the backlight module  110  according to the backlight data  410 , as illustrated in  FIG. 4A  and  FIG. 4B . Here, the color distribution of the light-emitting pattern  412  corresponds to the color distribution of the expected image  400  (step S 303 ). 
         [0052]    In the present embodiment, the light-emitting pattern  412  is constituted by a first color region  412 C including red, green, and blue, a red second color region  412 R, a green third color region  412 G, and a blue fourth color region  412 B. The red, green, and blue portions of the first color region  412 C correspond to the red, green, and blue images of the expected image  400  respectively. The red second color region  412 R corresponds to the red image of the expected image  400 . The green third color region  412 G corresponds to the green image of the expected image  400 . In addition, the blue fourth color region  412 B corresponds to the blue image of the expected image  400 . 
         [0053]    To give an example, referring to  FIG. 4A  and  FIG. 4B  simultaneously, based on the first color region  412 C, the red portion thereof corresponds to the red flowers E R1 , E R2 , and the red portion of the gray cloud E Gray . On the other hand, the green portion thereof corresponds to the green mountains E G  and the green portion of the gray cloud E Gray . The blue portion thereof corresponds to the blue river E B  and the blue portion of the gray cloud E Gray . Furthermore, the red second color region  412 R corresponds to the red flowers E R1 , E R2 , and the red portion of the gray cloud E Gray . The green third color region  412 G corresponds to the green mountains E G  and the green portion of the gray cloud E Gray . The blue fourth color region  412 B corresponds to the blue river E B  and the blue portion of the gray cloud E Gray . 
         [0054]    In particular, the first color region  412 C of the present embodiment is, for example, the summed result of the second, the third, and the fourth color regions  412 R,  412 G, and  412 B. In other words, the red portion of the first color region  412 C is substantially the red second color region  412 R, the green portion of the first color region  412 C is substantially the green third color region  412 G, and the blue portion of the first color region  412 C is substantially the blue fourth color region  412 B. 
         [0055]    Referring to  FIG. 2  and  FIG. 4B  simultaneously, the second color region  412 R is provided by at least a portion of the first color light-emitting units  110 R (red light-emitting units), for example. The third color region  412 G, for instance, is provided by at least a portion of the second color light-emitting units  110 G (green light-emitting units). The fourth color region  412 B, for example, is provided by at least a portion of the third color light-emitting units  110 B (blue light-emitting units). Moreover, the first color region  412 C is provided by at least a portion of the first color light-emitting units  110 R (red light-emitting units), at least a portion of the second color light-emitting units  110 G (green light-emitting units), and at least a portion of the third color light-emitting units  110 B (blue light-emitting units). Here, the first color region  412 C is deemed as the light-emitting effect generated as the first color light-emitting units  110 R (red light-emitting units), the second color light-emitting units  110 G (green light-emitting units), and the third color light-emitting units  110 B (blue light-emitting units) respectively provide the second color region  412 R, the third color region  412 G, and the fourth color region  412 B at the same time. 
         [0056]    Therefore, the present embodiment locally controls the first, the second, and the third color light-emitting units  110 R,  110 G, and  110 B. In addition, the light-emitting intensity of the first, the second, and the third color light-emitting units  110 R,  110 G, and  110 B can be modified according to the gray-scale value of the expected image  400 . For example, the first color light-emitting units  10 R (red light-emitting units) allow the second color region  412 R to obtain different light-emitting intensities base on the deep-red flower E R1  and the light-red flower E R2 . In another example, the evening sky (the black portion) is achieved by not-lightening the first, the second, and the third color light-emitting units  110 R,  110 G, and  110 B (red, green, and blue light-emitting units). 
         [0057]    Hence, the first, the second, the third, and the fourth color regions  412 C,  412 R,  412 G, and  412 B generated with the first, the second, and the third color light-emitting units  110 R,  110 G, and  110 B can provide a gray-scale number of a certain level. Consequently, the backlight module  110  elevates the overall gray-scale number of the display image of the display apparatus  100 , so as to enhance the contrast ratio and resolution of the display image. In one embodiment, the backlight module  110  provides a gray-scale number of at least 2 bits. 
         [0058]    It should be noted that the backlight module  110  provides the first, the second, the third, and the fourth color regions  412 C,  412 R,  412 G, and  412 B for elevating the gray-scale number of the display image. Thus, although the display panel  120  of the present embodiment utilizes the passive LCD panel with less gray-scale number, the display apparatus  100  can still compensate the gray-scale number of the display image through the backlight module  110 . Hence, the display apparatus  100  with the passive LCD panel not only has the advantages of low fabrication cost and low power consumption, but can also prevent the problem of insufficient gray-scale number in the conventional passive LCD apparatus. 
         [0059]    In the following embodiment, the passive LCD panel is illustrated as an example. Herein, the passive LCD panel provides a gray-scale number of at least  6  bits. However, those skilled in the art can apply the LC layer  126  (i.e. STN LC) to provide a gray-scale number of at least 4 bits, and utilize the method of adjusting the gray-scale number with time control to further provide a gray-scale number of at least 2 bits. 
         [0060]    As shown in  FIG. 1 ,  FIG. 4A , and  FIG. 4C , the controller  130  of the present embodiment determines a display pattern  422  of the display panel  120  according to the display data  420  (step S 305 ). In the present embodiment, the display panel  120  merely provides non-multicolored display images such as black, gray, and white. Moreover, the display pattern  422  is constituted by a first gray-scale pattern  422 C, a second gray-scale pattern  422 R, a third gray-scale pattern  422 G, and a fourth gray-scale pattern  422 B, for example. The first, the second, the third, and the fourth gray-scale patterns  422 C,  422 R,  422 G, and  422 B are respectively collocated with the first, the second, the third, and the fourth color regions  412 C,  412 R,  412 G, and  412 B aforementioned in the subsequent process to further display the image. However, in the present invention, the display panel  120  not only displays black, gray, and white images. In other embodiments, the display panel  120  also displays multicolored images. 
         [0061]    To give an example, the backlight module  110  and the display panel  120  are assumed to provide gray-scale numbers of 2 bits and 6 bits respectively, so that the gray-scale number of the expected image  400  is 8 bits. That is, in the situation where the minimum to maximum gray-scale values of the expected image  400  are 0˜63, the red flowers D R1  and D R2 , the green mountains D G , the blue river D B , the gray cloud D Gray , and the like that are recorded in the display data  420  are represented as red R 0 ˜R 63 , green G 0 ˜G 63 , and blue B 0 ˜B 63 . 
         [0062]    Take the gray cloud D Gray  as an example, if the gray-scale value representing the gray cloud D Gray  is (R 60 , G 50 , B 20 ) in the display data  420 , where the 60, 50, and 20 are respectively the first initial color gray-scale value, the second initial color gray-scale value, and the third initial color gray-scale value, then the minimum value 20 of the first, the second, and the third initial color gray-scale values  60 ,  50 , and  20  is used as the specific gray-scale value. The gray-scale value representing the gray cloud D Gray  in the first sub-display data is set to be (R 20 , G 20 , B 20 ) through this specific gray-scale value  20 . Nevertheless, the specific gray-scale value is the minimum value of the first, the second, and the third initial color gray-scale values in the present embodiment, but the present invention is not limited thereto. 
         [0063]    Furthermore, the first color gray-scale value  40  is obtained from the difference between the first initial color gray-scale value  60  and the specific gray-scale value  20 . With this first color gray-scale value  40 , the gray-scale value representing the gray cloud D Gray  in the second sub-display data is set to be (R 40 , G 0 , B 0 ). Similarly, the second color gray-scale value  30  is obtained from the difference between the second initial color gray-scale value  50  and the specific gray-scale value  20 . With this second color gray-scale value  30 , the gray-scale value representing the gray cloud D Gray  in the third sub-display data is set to be (R 0 , G 30 , B 0 ). The third color gray-scale value  0  is obtained from the difference between the third initial color gray-scale value  20  and the specific gray-scale value  20 . With this third color gray-scale value  0 , the gray-scale value representing the gray cloud D Gray  of the fourth sub-display data is set to be (R 0 , G 0 , B 0 ). 
         [0064]    Hence, the controller  130  determines the gray-scale patterns configured to represent the gray clouds in the first, the second, the third, and the fourth gray-scale patterns  422 C,  422 R,  422 G, and  422 B according to the gray-scale value (R 20 , G 20 , B 20 ) configured to represent the gray cloud in the first sub-display data, the gray-scale value (R 40 , G 0 , B 0 ) configured to represent the gray cloud in the second sub-display data, the gray-scale value (R 0 , G 30 , B 0 ) configured to represent the gray cloud in the third sub-display data, and the gray-scale value (R 0 , G 0 , B 0 ) configured to represent the gray cloud in the fourth sub-display data respectively. Here, the sum of the gray-scale values (R 20 , G 20 , B 20 ), (R 40 , G 0 , B 0 ), (R 0 , G 30 , B 0 ), and (R 0 , G 0 , B 0 ) that are configured to represent the gray clouds in the first, the second, the third, and the fourth sub-display data substantially equals to the gray-scale value (R 60 , G 50 , B 20 ) configured to represent the gray cloud in the display data. 
         [0065]    However, those skilled in the art should be able to determine other gray-scale patterns (i.e. the red flowers, the green mountains, the blue river, the black evening sky) with the first, the second, the third, and the fourth sub-display data. Thus, the method is not repeated herein. In short, the controller  130  of the present embodiment determines the first, the second, the third, and the fourth gray-scale patterns  422 C,  422 R,  422 G, and  422 B with the first, the second, the third, and the fourth sub-display data. 
         [0066]    Subsequently, the display apparatus  100  displays the expected image  400  through the light-emitting pattern  412  provided by the backlight module  110  and the display pattern  422  provided by the display panel  120 . The light-emitting pattern  412  has the first color region  412 C, the second color region  412 R, the third color region  412 G, and the fourth color region  412 B. On the other hand, the display pattern  422  has the first gray-scale pattern  422 C, the second gray-scale pattern  422 R, the third gray-scale pattern  422 G, and the fourth gray-scale pattern  422 B. 
         [0067]    More specifically, in the present embodiment, the first color region  412 C and the first gray-scale pattern  422 C are provided simultaneously with the backlight module  110  and the display panel  120 . The display apparatus  100  displays a first sub-image. Next, the second color region  412 R and the second gray-scale pattern  422 R are provided simultaneously with the backlight module  110  and the display panel  120 . The display apparatus  100  displays a second sub-image. Thereafter, the third color region  412 G and the third gray-scale pattern  422 G are provided simultaneously with the backlight module  110  and the display panel  120 . The display apparatus  100  displays a third sub-image. Then, the fourth color region  412 B and the fourth gray-scale pattern  422 B are provided simultaneously with the backlight module  110  and the display panel  120 . The display apparatus  100  displays a fourth sub-image. Subsequently, the first, the second, and the third sub-images are displayed repetitively and consecutively. The display frequency of the first, the second, the third, and the fourth sub-images is approximately 240 Hz. 
         [0068]    As illustrated in the foregoing, the display apparatus  100  of the present embodiment displays images by displaying the first sub-image, the second sub-image, the third sub-image, and the fourth sub-image sequentially and repetitively. It should be noted that in the present embodiment, by sequentially displaying the first sub-image constituted by the first color region and the first gray-scale pattern, the second sub-image constituted by the second color region and the second gray-scale pattern, the third sub-image constituted by the third color region and the third gray-scale pattern, and the fourth sub-image constituted by the fourth color region and the fourth gray-scale pattern, the color saturation and the contrast ratio of the display image are greatly enhanced. In addition, the color breakup (CBU) resulted from the conventional color sequential display apparatus is effectively improved. 
       Second Embodiment 
       [0069]    The concept to be illustrated in the present embodiment is similar to that of the first embodiment. The main difference between the two is that the light-emitting pattern and the display pattern of the present embodiment respectively simplify a color region and a gray-scale region so as to further simplify the driving method. However, the same or similar reference numbers in the present embodiment and the foregoing embodiment represent the same or similar elements. Accordingly, no further description thereof is provided hereinafter. 
         [0070]    Referring to  FIG. 1˜FIG .  3  and  FIG. 4A , it must be illustrated that the controller  130  in the present embodiment also outputs the backlight data  410  and the display data  420  according to the color distribution of the expected image  400  (step S 301 ), and determines the light-emitting pattern of the backlight module  110  and the display pattern of the display panel  120  according to the backlight data  410  and the display data  420 , where the color distribution of the light-emitting pattern corresponds to the color distribution of the expected image  400  (steps S 303  and S 305 ). However, the illustration of this part can refer to  FIG. 1˜FIG .  3  and  FIG. 4A  of the first embodiment and the descriptions thereof. In the following embodiment, the light-emitting pattern and the display pattern of the present embodiment and the relationship therebetween are mainly illustrated. 
         [0071]    Referring to  FIG. 5A , a light-emitting pattern  512  of the present embodiment is constituted by a red first color region  512 R, a green second color region  512 G, and a blue third color region  512 B. The red first color region  512 R corresponds to the red images of the expected image  400  (shown in  FIG. 4A ), such as the red flowers E R1 , E R2 , and the red portion of the gray cloud E Gray  in  FIG. 4A . The green second color region  512 G corresponds to the green images of the expected image  400 , such as the mountains E G  and the green portion of the gray cloud E Gray  in  FIG. 4A . The blue third color region  512 B corresponds to the blue images of the expected image  400 , such as the blue river E B  and the blue portion of the gray cloud E Gray  in  FIG. 4A . 
         [0072]    In the present embodiment, the first color region  512 R is provided by at least a portion of the first color light-emitting units  110 R (red light-emitting units), for example. The second color region  512 G, for instance, is provided by at least a portion of the second color light-emitting units  110 G (green light-emitting units). Moreover, the third color region  512 B is provided by at least a portion of the third color light-emitting units  110 B (blue light-emitting units), for example. 
         [0073]    As illustrated in the foregoing, the present embodiment locally controls the first, the second, and the third color light-emitting units  110 R,  110 G, and  110 B, so that the light-emitting intensities thereof vary in accordance with the color distribution of the expected image  400 . For example, the first color light-emitting units  110 R (red light-emitting units) allow the first color region  512 R to obtain different light-emitting intensities according to the deep-red flower E R1  and the light-red flower E R2 . In another example, the evening sky (the black portion) is achieved by not-lightening the first, the second, and the third color light-emitting units  110 R,  110 G, and  110 B (red, green, and blue light-emitting units). 
         [0074]    Hence, the first, the second, and the third color regions  512 R,  512 G, and  512 B generated with the first, the second, and the third color light-emitting units  110 R,  110 G, and  110 B provide a gray-scale number of a certain level. Consequently, the backlight module  110  elevates the overall gray-scale number of the display image of the display apparatus  100 , so as to enhance the contrast ratio and resolution of the display image and reduce the power consumption of the display apparatus  100 . In one embodiment, the backlight module  110  provides a gray-scale number of at least 2 bits. 
         [0075]    Since the backlight module  110  provides the first, the second, and the third color regions  512 R,  512 G, and  512 B for elevating the gray-scale number of the display image, although the display panel  120  of the present embodiment applies the passive LCD panel with less gray-scale number, the display apparatus  100  can still compensate the gray-scale number of the display image through the backlight module  110 . Consequently, the display apparatus  100  with the passive LCD panel has the advantages of low fabrication cost and low power consumption. Additionally, the problem of insufficient gray-scale number in the conventional passive LCD apparatus is also prevented. 
         [0076]    On the other hand, as illustrated in  FIG. 5B , a display pattern  522  of the present embodiment is constituted by a first gray-scale pattern  522 R, a second gray-scale pattern  522 G, and a third gray-scale pattern  522 B, for example. The first, the second, and the third gray-scale patterns  522 R,  522 G, and  522 B are non-colored gray-scale images, for instance. In the subsequent process the first, the second, and the third gray-scale patterns  522 R,  522 G, and  522 B are respectively collocated with the first, the second, and the third color regions  512 R,  512 G, and  512 B to further display the image. 
         [0077]    In the following embodiment, the passive LCD panel is illustrated as an example. Herein, the passive LCD panel provides a gray-scale number of at least 6 bits. However, those skilled in the art can apply the LC layer  126  (i.e. STN LC) to provide a gray-scale number of at least 4 bits, and utilize the method of adjusting the gray-scale number with time control to further provide a gray-scale number of at least 2 bits, so that the passive LCD panel has a gray-scale number of at least  6  bits. 
         [0078]    Referring to  FIG. 1  and  FIG. 4A  simultaneously, as aforementioned, the backlight module  110  and the display panel  120  are assumed to provide gray-scale numbers of 2 bits and 6 bits respectively, so that the gray-scale number of the expected image  400  is 8 bits. That is, in the situation where the minimum to maximum gray-scale values of the expected image  400  are 0˜63, the red flowers D R1  and D R2 , the green mountains D G , the blue river D B , the gray cloud D Gray , and the like that are recorded in the display data  420  are represented as red R 0 ˜R 63 , green G 0 ˜G 63 , and blue B 0 ˜B 63 . 
         [0079]    Take the gray cloud D Gray  as an example, the gray-scale value representing the gray cloud D Gray  is (R 60 , G 50 , B 20 ) in the display data  420 , where the 60, 50, and 20 are respectively the first color gray-scale value, the second color gray-scale value, and the third color gray-scale value. In the present embodiment, the first color gray-scale value is used to set the gray-scale value representing the gray cloud D Gray  in the first sub-display data to be (R 60 , G 0 , B 0 ). The second color gray-scale value is used to set the gray-scale value representing the gray cloud D Gray  in the second sub-display data to be (R 0 , G 50 , B 0 ). Moreover, the third color gray-scale value is used to set the gray-scale value representing the gray cloud D Gray  in the third sub-display data to be (R 0 , G 0 , B 20 ). 
         [0080]    Hence, the controller  130  determines the gray-scale patterns configured to represent the gray clouds in the first, the second, and the third gray-scale patterns  522 R,  522 G, and  522 B according to the gray-scale value (R 60 , G 0 , B 0 ) configured to represent the gray cloud in the first sub-display data, the gray-scale value (R 0 , G 50 , B 0 ) configured to represent the gray cloud in the second sub-display data, and the gray-scale value (R 0 , G 0 , B 20 ) configured to represent the gray cloud in the third sub-display data respectively. Here, the sum of the gray-scale values (R 60 , G 0 , B 0 ), (R 0 , G 50 , B 0 ), and (R 0 , G 0 , B 20 ) that are configured to represent the gray clouds in the first, the second, and the third sub-display data substantially equals to the gray-scale value (R 60 , G 50 , B 20 ) configured to represent the gray cloud in the display data. 
         [0081]    However, those skilled in the art should be able to determine other gray-scale patterns (i.e. the red flowers, the green mountains, the blue river, the black evening sky) with the first, the second, and the third sub-display data. Thus, the method is not repeated herein. In short, the controller  130  of the present embodiment determines the first, the second, and the third gray-scale patterns  522 R,  522 G, and  522 B with the first, the second, and the third sub-display data. 
         [0082]    Next, the display apparatus  100  displays the expected image  400  through the light-emitting pattern  512  provided by the backlight module  110  and the display pattern  522  provided by the display panel  120 . The light-emitting pattern  512  has the first color region  512 R, the second color region  512 G, and the third color region  512 B. On the other hand, the display pattern  522  has the first gray-scale pattern  522 R, the second gray-scale pattern  522 G, and the third gray-scale pattern  522 B. 
         [0083]    Referring to  FIG. 5A  and  FIG. 5B  simultaneously, in the present embodiment, the first color region  512 R and the first gray-scale pattern  522 R are provided simultaneously with the backlight module  110  and the display panel  120 . The display apparatus  100  displays a first sub-image. Thereafter, the second color region  512 G and the second gray-scale pattern  522 G are provided simultaneously with the backlight module  110  and the display panel  120 . The display apparatus  100  displays a second sub-image. Then, the third color region  512 B and the third gray-scale pattern  522 B are provided simultaneously with the backlight module  110  and the display panel  120 . The display apparatus  100  displays a third sub-image. Subsequently, the first, the second, and the third sub-images are displayed repetitively and consecutively. The display frequency of the first, the second, and the third sub-images is approximately 180 Hz. 
         [0084]    As illustrated in the foregoing, the display apparatus  100  of the present embodiment displays images by displaying the first sub-image, the second sub-image, and the third sub-image sequentially and repetitively. It should be noted that in the present embodiment, by sequentially displaying the first sub-image constituted by the first color region and the first gray-scale pattern, the second sub-image constituted by the second color region and the second gray-scale pattern, and the third sub-image constituted by the third color region and the third gray-scale pattern, the color saturation and the contrast ratio of the display image are greatly enhanced. In addition, the CBU of the display image resulted from the conventional color sequential display apparatus is improved. 
       Third Embodiment 
       [0085]    The concept to be illustrated in the present embodiment is similar to that of the foregoing embodiment. The main difference between the two is that the light-emitting pattern and the display pattern of the present embodiment are simplified to a multicolored region and a multicolored pattern respectively. However, the same or similar reference numbers in the present embodiment and the foregoing embodiment represent the same or similar elements. Accordingly, no further description thereof is provided hereinafter. 
         [0086]    Referring to  FIG. 6 ,  FIG. 6  is a partial cross-sectional view of a display panel according to a third embodiment of the present invention. A display panel  620  of the present embodiment includes a pixel array substrate  622 , a color filter  624 , and an LC layer  126  clamped between the pixel array substrate  622  and the color filter  624 . The pixel array substrate  622  is, for example, a passive array substrate. The color filter  624  includes a plurality of color filter patterns  624 R,  624 G, and  624 B. The LC layer  126  is an STN LC layer, for instance. 
         [0087]    Obviously, in other embodiments, the pixel array substrate  622  is also an active device array substrate or a display panel of other types. In other words, the present invention does not limit the type of the display panel  620 . In addition, the display panel  620  of the present embodiment further includes other components, and  FIG. 6  omits the other components mainly to facilitate the illustration of the following embodiment. 
         [0088]    Referring to  FIG. 1˜FIG .  3 ,  FIG. 4A , and  FIG. 6  simultaneously, the controller  130  in the present embodiment also outputs the backlight data  410  and the display data  420  according to the color distribution of the expected image  400  (step S 301 ), and determines the light-emitting pattern of the backlight module  110  and the display pattern of the display panel  620  according to the backlight data  410  and the display data  420 , where the color distribution of the light-emitting pattern corresponds to the color distribution of the expected image  400  (steps S 303  and S 305 ). However, the illustration of this part can refer to  FIG. 1˜FIG .  3  and  FIG. 4A  of the first embodiment and the descriptions thereof. In the following embodiment, the light-emitting pattern and the display pattern of the present embodiment and the relationship therebetween are mainly illustrated. 
         [0089]    Referring to  FIG. 6 ,  FIG. 7A , and  FIG. 7B  simultaneously, specifically, the controller  130  (shown in  FIG. 1 ) of the present embodiment determines a light-emitting pattern  712  and a display pattern  722  according to the backlight data  410  and the display data  420  (shown in  FIG. 4A ) respectively. In the present embodiment, the display panel  620  makes the display pattern  722  to be a multicolored pattern through the disposition of the color filter  624 . The color distribution of the multicolored pattern corresponds to the color distribution of the expected image  400 . 
         [0090]    Moreover, the light-emitting pattern  712  of the present embodiment is a multicolored region, and the color distribution of the multicolored region corresponds to the color distribution of the expected image  400 . Here, the multicolored region is provided by at least a portion of the first color light-emitting units  110 R (red light-emitting units), at least a portion of the second color light-emitting units  110 G (green light-emitting units), and at least a portion of the third color light-emitting units  110 B (blue light-emitting units) of the backlight module  110  (shown in  FIG. 2 ). 
         [0091]    As aforementioned, the backlight module  110  in the display apparatus  100  of the present embodiment provides multicolored light-emitting patterns, and the display panel  120  thereof also provides multicolored display patterns. Thus, the color saturation and the contrast ratio of the display image of the display apparatus  100  are greatly enhanced. 
         [0092]    Furthermore, as the first, the second, and the third color light-emitting units  110 R,  110 G, and  110 B are locally controlled, the light intensities thereof vary in accordance with the color distribution of the expected image  400 . For example, the first color light-emitting units  110 R (red light-emitting units) allow the light-emitting pattern  712  (multicolored region) to obtain different light-emitting intensities according to the deep-red flower E R1  and the light-red flower E R2  in  FIG. 4A . In another example, the evening sky (the black portion) is achieved by not-lightening the first, the second, and the third color light-emitting units  110 R,  110 G, and  110 B (red, green, and blue light-emitting units). 
         [0093]    Hence, the backlight module  110  of the present embodiment provides a gray-scale number of a certain level through the light-emitting pattern  712  (multicolored region), which is generated by the first, the second, and the third color light-emitting units  110 R,  110 G, and  110 B. The backlight module  110  therefore elevates the overall gray-scale number of the display image of the display apparatus  100 . In one embodiment, the backlight module  110  provides a gray-scale number of at least 2 bits. 
         [0094]    It should be noted that the backlight module  110  provides the light-emitting pattern  712  (multicolored region) which is configured to elevate the gray-scale number of the display image. Therefore, in term of the passive LCD panel with the passive array substrate, the light-emitting pattern  712  of the backlight module  110  of the present embodiment compensates the problem of insufficient gray-scale number in passive LCD panels. More specifically, in the present embodiment, the display apparatus  100  applying the passive LCD panel not only has the advantages of low fabrication cost and low power consumption, but the display image thereof also has good display quality. 
         [0095]    As illustrated in the foregoing, in the three embodiments above-mentioned, the backlight module in the display apparatus is collocated with display panels of multiple types, such as a conventional display panel with color filter, a display panel with color filter-less design, a passive LCD panel, an active LCD panel, and the like. Take the display apparatus having the passive LCD panel as an example, this display apparatus has the advantages of low power consumption, fabrication cost and time reduction. Take the display apparatus with the color filter-less design as an example, this display apparatus is driven through the color sequential method of displaying sub-images sequentially, so as to improve the CBU phenomenon. In short, both the display apparatus and the driving method thereof of the foregoing embodiment enhance the display quality. 
         [0096]    In summary, the display apparatus and the driving method thereof enhance the display quality. The backlight module of the display apparatus provides the light-emitting pattern that corresponds to the color distribution of the expected image, and the backlight module is collocated with display panels of multiple types. Overall, the present invention has advantages of elevating color saturation, contrast ratio, gray-scale number of the display image, and resolution, and reducing power consumption. 
         [0097]    Although the present invention has been described with reference to the above embodiments, it will be apparent to one of the ordinary skill in the art that modifications to the described embodiment may be made without departing from the spirit of the invention. Accordingly, the scope of the invention will be defined by the attached claims not by the above detailed descriptions.