Patent Publication Number: US-6982690-B2

Title: Display apparatus with a driving circuit in which every three adjacent pixels are coupled to the same data line

Description:
BACKGROUND OF THE INVENTION 
   This application claims the benefit of Taiwan application Serial No. 091106436, filed Mar. 29, 2002. 
   1. Field of the Invention 
   The invention relates in general to a display apparatus, and more particularly to a display apparatus with a driving circuit in which every three adjacent pixels are coupled to the same data line. 
   2. Description of the Related Art 
   Liquid Crystal Displays (LCDs) have been widely used throughout the world because they feature the favorable properties of thinness and lightness and generate low levels of radiation. 
     FIG. 1  shows a circuit diagram illustrating a conventional LCD panel. The display panel includes a plurality of pixels (P). The pixels are arranged in the form of a matrix on the display panel. The display panel includes an active matrix driving circuit for driving the pixels. The active matrix driving circuit includes a plurality of scan lines (S), a plurality of data lines (D), and a plurality of switching devices. The switching devices are set in the pixels for selectively transmitting the corresponding data signals to the pixels. The switching device can be a thin film transistor (TFT), such as an n-type field effect transistor (n-FET) or a p-type field effect transistor (p-FET). In  FIG. 1 , the switching device of each pixel includes a thin film transistor. The thin film transistor in each pixel includes a gate electrode, a first source/drain electrode, and a second source/drain electrode. The gate electrode of the thin film transistor is coupled to the corresponding scan line, and the first source/drain electrode is coupled to the corresponding data line. Using the pixel P(m,n) as an example the pixel P(m,n) includes a thin film transistor M 1 . The gate electrode of the thin film transistor M 1  is coupled to the scan line S m , and the first source/drain electrode of the thin film transistor M 1  is coupled to the data line D n . Each scan line is perpendicular to each data line. Each pixel in the same pixel row is coupled to the same scan line, and each pixel in the same pixel column is coupled to the same data line, as shown in  FIG. 1 . 
     FIG. 2  shows the configuration of a conventional active matrix liquid crystal display. The conventional active matrix liquid crystal display includes a display panel  202 , an X board  212 , and a Y board  214 . The display panel  202  includes the pixels and the active matrix driving circuit, as shown in  FIG. 1 . The Y board  214  is coupled to a plurality of scan drivers  206  set in the tape carrier packages  210 . Each scan driver  206  is coupled to the Y board  214  and the corresponding scan lines respectively. The X board  212  is coupled to a plurality of data drivers  204  set in the tape carrier packages (TCP)  208 . Each data driver  204  is coupled to the X board  212  and the corresponding data lines respectively. The Y board  214  and the scan drivers  206  are used for enabling the corresponding scan lines through inputting a scan signal into the scan line. When the scan line is enabled, each pixel in the pixel row coupled to the scan line can be turned ON. The X board  212  and the data drivers  204  are used for inputting the data signals to the corresponding pixels through the corresponding data lines when the pixels are turned ON. 
   The conventional active matrix liquid crystal display has the following disadvantages. First, a large number of data lines are needed. For example, an active matrix display panel has a resolution of 1024×768; that is, the active matrix display panel has 1024 pixel columns and each pixel column has 1024×3=3072 pixels. Therefore, the active matrix display panel must include 3072 data lines. This is a large number of data lines. First, since so many data lines are needed, the pitch between the adjacent data lines must be small. Second, each data line is coupled to the corresponding data driver through the outer lead of the tape carrier package, and it is both difficult and elaborate to connect all data lines to the corresponding outer leads of the tape carrier packages. Third, the aperture ratio of the display panel will be decreased since the number of data lines is so large. 
     FIG. 3  shows a diagram of a conventional time domain multiplex driving circuit. In the conventional time domain multiplex driving circuit, every two adjacent pixels in the same pixel row are coupled to the same data line. These two pixels are set on the left and right sides of the data line respectively. The pixel set on the left side of the data line is called the left pixel (LP), and the pixel set on the right side of the data line is called the right pixel (RP). The switching devices for the pixels LP and RP are different. Take the pixels LP(m,n) and RP(m,n) as an example. These two pixels are both coupled to the same scan line S m  and the same data line D n . The pixel LP(m,n) is set on the left side of the data line D n , and the pixel RP(m,n) is set on the right side of the data line D n , as shown in  FIG. 3 . The pixel RP(m,n) switching device includes a thin film transistor M 2 . The gate electrode of the thin film transistor M 2  is coupled to the scan line S m , and the first source/drain electrode of the thin film transistor M 2  is coupled to the data line D n . The switching device of the pixel LP(m,n) is different from that of the pixel RP(m,n). The switching device of the pixel LP(m,n) includes two thin film transistors M 11  and M 12 . The gate electrode of the thin film transistor M 11  is coupled to the scan line S m+1 , and the first source/drain electrode of the thin film transistor M 11  is coupled to the data line D n . The gate electrode of the thin film transistor M 12  is coupled to the scan line S m , and the first source/drain electrode of the thin film transistor M 12  is coupled to the second source/drain electrode of the thin film transistor M 11 , as shown in  FIG. 3 . 
     FIG. 4  shows a timing chart for the scan signals of scan lines S m , S m+1 , and S m+2  and the ON and OFF status of the corresponding pixels LP(m,n), RP(m,n), LP(m+1,n), and RP(m+1,n) shown in  FIG. 3 . The method for driving a display panel with the above-described time domain multiplex driving circuit is called a time domain multiplex driving method. When the time domain multiplex driving method is executed, each pixel row is driven in turn by the time domain multiplex driving circuit. The time domain multiplex driving method includes two scanning procedures. The first scanning procedure is to selectively turn on the left pixels of the pixel row by turning on two corresponding TFTs of each of the left pixels and then feeding the corresponding data signals into the respective left pixels. The second scanning procedure is to selectively turn on the right pixels of the pixel row by turning on one corresponding TFT of each right pixel and then feeding the corresponding data signals into the respective right pixels. 
   Using pixels LP(m,n) and RP(m,n) shown in  FIG. 3  as an example, during time period T 1 , the scan lines S m  and S m+1  are enabled. The thin film transistors M 11  and M 12  can be turned ON, and a data signal can be input to the corresponding pixel LP(m,n) through the TFTs M 11  and M 12 . In the time period T 2 , only the scan line S m  is enabled. The thin film transistor M 2  can be turned ON, and a data signal can be input to the corresponding pixel RP(m,n) through the TFT M 2 . 
   In the time domain multiplex driving circuit, the above-described disadvantages of the conventional active matrix driving circuit can be improved. If the resolution of the display panel is 1024×768, for example, every two adjacent pixels in the same pixel row are coupled to one corresponding data line of the time domain multiplex driving circuit, and thus only 3072/2=1536 data lines are needed. 
   However, the conventional time domain multiplex driving circuit disclosed above has the following disadvantage. An equivalent capacitor between the gate electrode and the second source/drain electrode is created when the thin film transistor is turned ON. The output voltage will be lower than the input voltage of the thin film transistor, and the luminance of the pixel may be decreased because of the equivalent capacitor. This effect caused by the equivalent capacitor is called the feed-through effect. The larger the capacitance of the equivalent capacitor is, the larger the difference between the output voltage and the input voltage of the thin film transistor is. Take the pixels LP(m,n) and RP(m,n) shown in  FIG. 3  as an example. The switching device of the pixel RP(m,n) includes only one thin film transistor M 2  and the switching device of the pixel LP(m,n) includes two thin film transistors M 1  and M 12 . The data signal inputted to the pixel RP(m,n) only through the thin film transistors M 2  but the data signal inputted to the pixel LP(m,n) through two thin film transistors, M 11  and M 12 . Therefore, the equivalent capacitor of LP(m,n) is much larger than that of RP(m,n). During driving of the pixels by the time domain multiplex driving circuit, the luminance of the pixel LP(m,n) will be less than that of the pixel RP(m,n) when the data signals of the same magnitude are input to the pixels LP(m,n) and RP(m,n) respectively. Therefore, the luminance of the adjacent pixels may not be the same even when the data signals of the same magnitude are input to the respective pixels. Since pixel LP(m,n) includes two thin film transistors and the pixel RP(m,n) includes only one thin film transistor, the aperture ratio of these two adjacent pixels may not be the same. The luminance of the pixel can be affected by the aperture ratio of the pixel, and because of the feed-through effect and the aperture ratio of the pixel, the display performance of the liquid crystal display would thus be degraded. 
     FIGS. 5A˜5C  illustrate the conventional driving circuit shown in  FIG. 3  of the pixels, the pixel columns, and the pixel units respectively.  FIG. 5A  shows the conventional driving circuit of the pixels, as shown in  FIG. 3 . In reference to  FIG. 5B , the method used for inputting data signals into the corresponding pixels of the color display panel is, taking the adjacent pixels LP(m,n), RP(m,n), and LP(m,n+1) as an example, to input the data signal for showing red into the pixel LP(m,n), the data signal for showing green into the pixel RP(m,n), and the data signal for showing blue into the pixel LP(m,n+1) respectively. All other pixels in the same column as the pixel LP(m,n) are input with the data signals for showing red. The pixel column is thus called the red pixel column RPC 1 . In the same manner, all other pixels in the same column with the pixel RP(m,n) are input with the data signals to show green. The pixel column is thus called green pixel column GPC 1 . All other pixels in the same column with the pixel LP(m,n+1) are input with data signals to show blue; the pixel column is thus called blue pixel column BPC 1 . Following the same order, the pixel column that includes the pixel RP(m,n+1) is for displaying red, the pixel column that includes the pixel LP(m,n+2) is for displaying green, and the pixel column which includes the pixel RP(m,n+2) is for displaying blue respectively. Therefore, these three adjacent pixel columns are called red pixel column RPC 2 , green pixel column GPC 2 , and blue pixel column BPC 2  respectively. In reference to  FIG. 5C , taking the pixel unit PU 1  as an example, pixel unit PU 1  includes three adjacent pixels LP(m,n), RP(m,n), and LP(m,n+1). Since the pixel LP(m,n), RP(m,n), and LP(m,n+1) are for displaying red, green, and blue respectively, the displaying color of the pixel unit PU 1  can be controlled by controlling the luminance of these three pixels. In the same manner, the displaying color of the pixel unit PU 2  can be controlled by controlling the luminance of pixels RP(m,n+1), LP(m,n+2), and RP(m,n+2) respectively. Every three adjacent pixels are grouped into a pixel unit for displaying color, as shown in  FIG. 5C . 
   Taking pixel LP(m,n) of pixel unit PU 1  and pixel RP(m,n+1) of pixel unit PU 2  as an example, in  FIG. 5C , both pixels LP(m,n) and RP(m,n+1) are for displaying red. However, because the degree of the feed-through effect and the aperture ratio of these two pixels are different, the luminance of these two pixels can be different even when the magnitude of the data signals input to these two respective pixels are the same. In the same manner, the luminance of the pixel of pixel unit PU 1 , which is for displaying green, and the corresponding pixel of pixel unit PU 2  and the pixel of pixel unit PU 1 , which is for displaying blue, and the corresponding pixel of pixel unit PU 2  cannot be the same even when the respective input data signals are of the same magnitude. 
   Therefore, the color of the two adjacent pixel unit columns cannot be the same when inputting data signals of the same magnitude into these two adjacent pixel unit columns. This phenomenon is called odd-even line, and it may result in degradation of the liquid crystal display performance. 
   SUMMARY OF THE INVENTION 
   It is therefore an objective of the present invention to provide a display apparatus with a driving circuit for driving the pixels of the display apparatus so as to achieve the objectives, where the number of data lines can be further decreased and the odd-even line problem can be avoided. 
   According to the objectives of the present invention, it provides a display apparatus with a driving circuit in which every three adjacent pixels are coupled to the same data line. The display apparatus comprises a first scan line arranged in a first direction; a first data line arranged in a second direction, wherein the second direction is perpendicular to the first direction; a first pixel coupled to the first data line and the first scan line respectively; a second pixel coupled to the first data line and the first scan line respectively; a third pixel coupled to the first data line and the first scan line respectively; a first switching device in the first pixel for selectively transmitting a first data signal to the first pixel from the first data line; a second switching device in the second pixel for selectively transmitting a second data signal to the second pixel from the first data line; and a third switching device in the third pixel for selectively transmitting a third data signal to the third pixel from the first data line. 
   Other objects, features, and advantages of the invention will become apparent from the following detailed description of the preferred but non-limiting embodiments. The following description is made with reference to the accompanying drawings. 

   
     BRIEF DESCRIPTION OF DRAWINGS 
       FIG. 1  shows a circuit diagram illustrating a conventional liquid crystal display panel; 
       FIG. 2  shows the configuration of a conventional active matrix liquid crystal display; 
       FIG. 3  illustrates a conventional time domain multiplex driving circuit. 
       FIG. 4  shows a timing chart of the scan signals from scan lines S m , S m+1 , and S m+2  and the ON and OFF status of corresponding pixels LP(m,n), RP(m,n), LP (m+1,n), and RP(m+1,n) shown in  FIG. 3 ; 
       FIGS. 5A˜5C  illustrate the conventional driving circuit shown in  FIG. 3  of the pixels, the pixel columns, and the pixel units respectively. 
       FIG. 6  shows a diagram of the driving circuit according to the preferred embodiment of the present invention; 
       FIG. 7  shows a timing chart of the scan signals of scan lines S m , S m+1 , S m+2 , S m+3 , and S m+4  and the ON and OFF status of corresponding pixels P 1 (m,n), P 2 (m,n), P 3 (m,n), P 1 (m+1,n), P 2 (m+1,n), P 3 (m+1,n), P 1 (m+2,n), P 2 (m+2,n), and P 3 (m+2,n), shown in  FIG. 6 ; and 
       FIGS. 8A˜8C  illustrate the driving circuit according to the preferred embodiment of the present invention shown in  FIG. 6  of the pixels, the pixel columns, and the pixel units respectively. 
   

   DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS 
     FIG. 6  shows a diagram of the driving circuit according to the preferred embodiment of the present invention. Take the pixels in the m th  row, the first pixel P 1  (m,n), second pixel P 2 (m,n), and third pixel P 3 (m,n) shown in  FIG. 6  for example; these three adjacent pixels are coupled to the same scan line S m  and the same data line D n . It should be noted that if the resolution of the display panel is 1024×768, for example, only 3072/3=1024 data lines are needed to drive all pixels in the display panel. The number of data lines can be further decreased compared to the conventional time domain multiplex driving circuit described above, and the number of data drivers for driving the data lines can be decreased as well. The complexity and cost of manufacturing the driving circuit can also be reduced, and, since the number of data lines is decreased, the pitch between the data lines can be wider. Thus, it will be easier to couple each outer lead of the tape carrier packages (TCP) with the corresponding data line. In addition, the aperture ratio of the display panel may be higher because the number of the data lines are decreased. 
   Please refer to  FIG. 6 . The first pixel P 1 (m,n) is controlled by the first switching device, which includes two switches M 11  and M 12 . The first switching device is for selectively transmitting the data signal to the first pixel P 1 (m,n) from the data line D n  by controlling the ON/OFF status of switches M 11  and M 12 . The second pixel P 2 (m,n) is controlled by the second switching device, which includes two switches M 21  and M 22 . The second switching device is for selectively transmitting the data signal to the second pixel P 2 (m,n) from the data line D n  by controlling the ON/OFF status of switches M 21  and M 22 . The third pixel P 3 (m,n) is controlled by the third switching device, which includes only one switch M 3 . The third switching device is for selectively transmitting the data signal to the third pixel P 3 (m,n) from the data line D n  by controlling the ON/OFF status of switch M 3 . It should be noted that all the switches can be thin film transistors. In addition, the relative location of the first pixel P 1  (m,n), second pixel P 2 (m,n), and third pixel P 3 (m,n) does not have to be the same as shown in  FIG. 6 . The requirement for the relative location of these pixels, according to the present invention, is that the first pixel P 1 (m,n), the second pixel P 2 (m,n), and the third pixel P 3 (m,n) are three adjacent pixels in the same row and are coupled to the same scan line S m  and data line D n . 
   According to the preferred embodiment of the present invention, as shown in  FIG. 6 , the switching device of the first pixel P 1  (m,n) includes two switches M 11  and M 12 . The gate electrode of switch M 11  is coupled to the scan line S m+2 , and the drain electrode of switch M 11  is coupled to the equivalent capacitor C 1  of the first pixel P 1  (m,n). The drain electrode of switch M 12  is serially coupled to the source electrode of switch M 11 ; the gate electrode of switch M 12  is coupled to scan line S m ; and the source electrode of switch M 12  is coupled to data line D n . The switching device of the second pixel P 2 (m,n) includes two switches M 21  and M 22 . The gate electrode of switch M 21  is coupled to scan line S m+1 , and the drain electrode of switch M 21  is coupled to the equivalent capacitor C 2  of the second pixel P 2 (m,n). The drain electrode of switch M 22  is serially coupled to the source electrode of switch M 21 ; the gate electrode of switch M 22  is coupled to scan line S m ; and the source electrode of switch M 22  is coupled to data line D n . The switching device of the third pixel P 3 (m,n) includes only one switch M 3 . The gate electrode of switch M 3  is coupled to scan line S m ; the drain electrode of switch M 3  is coupled to the equivalent capacitor C 3  of the third pixel P 3 (m,n); and the source electrode of switch M 3  is coupled to the data line D n . In this manner, the switching device of the first pixel P 1  (m,n) is controlled by two scan lines S m  and S m+2 ; the switching device of the second pixel P 2 (m,n) is controlled by two scan lines S m  and S m+1 ; and the switching device of the third pixel P 3 (m,n) is controlled by the scan line S m  only. All pixels in the same row can be divided into three groups according to the coupling scan line(s). Taking the m th  pixel row as an example, all pixels of the first pixel group are controlled by the scan lines S m  and S m+2 , just as is the first pixel P 1  (m,n). All pixels of the second pixel group are controlled by scan lines S m  and S m+1 , as is the second pixel P 2 (m,n). All pixels of the third pixel group are controlled by scan lines S m  only, such as the third pixel P 3 (m,n). 
     FIG. 7  shows a timing chart of the scan signals of scan lines S m , S m+1 , S m+2 , S m+3 , and S m+4  and the ON and OFF status of corresponding pixels P 1 (m,n), P 2 (m,n), P 3 (m,n), P 1 (m+1,n), P 2 (m+1,n), P 3 (m+1,n), P 1  (m+2,n), P 2 (m+2,n), and P 3 (m+2,n), shown in  FIG. 6 . The driving method executed by the above-described driving circuit is used for driving each pixel row in turn. The driving method includes three scanning procedures. The first scanning procedure is used for turning ON all pixels of the first pixel group in the same row and then applying the corresponding data signals to these pixels respectively. The second scanning procedure is used for turning ON all pixels of the second pixel group in the same row and then inputting the corresponding data signals into the pixels respectively. The third scanning procedure is used for turning ON all pixels of the third pixel group in the same row and then inputting the corresponding data signals into the pixels respectively. 
   Using pixels P 1 (m,n), P 2 (m,n), and P 3 (m,n) in the m th  row as an example we see that in time period T 1 , the first scanning procedure is executed so that scan lines S m  and S m+2  are enabled. Scan line S m+2  is coupled to the gate electrode of switch M 11 , and scan line S m  is coupled to the gate electrode of switch M 12 . In this manner, switches M 11  and M 12  can be turned ON in the time period T 1 , and the data signal for the first pixel P 1  (m,n) can be transmitted to the first pixel P 1  (m,n) from data line D n  through switches M 12  and M 11 . In addition, all other data signals can be transmitted to the corresponding pixels in the m th row , which are controlled by scan lines S m  and S m+2 . It should be noted that during the time period T 1 , switch M 22  of the second switching device can be turned ON since scan line S m  is enabled. However, since switch M 21  of the second switching device is OFF because scan line S m+1  is disabled, the data signal to be input to the first pixel P 1  (m,n) cannot be input to the second pixel P 2 (m,n) in the time period T 1 . After the data signals are input to the pixel P 1  (m,n), as well as all others pixels in the m th  row, which belong to the first pixel group, the scan line S m+2  is disabled. The switch M 11  can be turned OFF after scan line S m+2  is disabled, and in this manner, the first scanning procedure is completed. 
   In time period T 2 , the second scanning procedure is executed so that scan lines S m  and S m+1  are enabled. The scan line S m+1  is coupled to the gate electrode of switch M 21 , and scan line S m  is coupled to the gate electrode of switch M 22 . In this manner, the switches M 21  and M 22  can be turned ON in time period T 2 , and the data signal for the second pixel P 2 (m,n) can be transmitted to the second pixel P 2 (m,n) from data line D n  through switches M 22  and M 21 . In addition, all other data signals can be transmitted to the corresponding pixels in the m th  row, which are controlled by scan lines S m  and S m+1  as well. It should be noted that during time period T 2 , switch M 12  of the first switching device can be turned ON since scan line S m  is enabled. However, switch M 11  of the second switching device is OFF because the scan line S m+2  is disabled, the data signal for inputting to the second pixel P 2 (m,n) cannot be input to the first pixel P 1  (m,n) in the time period T 2 . After the data signals are input into pixel P 2 (m,n), as well as all others pixels in the m th  row, which belong to the second pixel group, scan line S m+1  is disabled. The switch M 21  can be turned OFF after the scan line S m+1  is disabled. In this manner, the second scanning procedure is accomplished. 
   In time period T 3 , the third scanning procedure is executed so that scan line S m  is enabled. The scan line S m  is coupled to the gate electrode of the switch M 3 . In this manner, the switches M 3  can be turned ON in time period T 3 , and the data signal for the third pixel P 3 (m,n) can be transmitted to the third pixel P 3 (m,n) from the data line D n  through the switch M 3 . In addition, all other data signals can be transmitted to the corresponding pixels in the m th  row, which is controlled only by scan line S m  as well. It should be noted that during the time periods T 1  and T 2 , the switch M 3  of the third switching device can be turned ON since scan line S m  is enabled. Therefore, the data signals for inputting into the first pixel P 1  (m,n) and the second pixel P 2 (m,n) can be input into the third pixel P 3 (m,n) respectively. However, when the third scanning procedure is executed during time period T 3 , the exact data signal specific to the third pixel P 3 (m,n) can be input into the third pixel P 3 (m,n). In addition, the switch M 12  of the first switching device and the switch M 22  of the second switching device can be turned ON since scan line S m  is enabled. However, since the switch M 1  of the first switching device is OFF, scan line S m+2  is disabled, switch M 21  of the second switching device is OFF, scan line S m+1  is disabled, and the data signal for input to the third pixel P 3 (m,n) cannot be input to the first pixel P 1  (m,n) or the second pixel P 2 (m,n). In this manner, after executing the first, second, and third scanning procedures, all the exact data signals of the pixels in the m th  row have been input. 
   Each pixel row is driven in turn by executing the driving method described above. Therefore, the driving circuit can control the luminance of each pixel in the display panel. 
     FIGS. 8A˜8C  illustrate the conventional driving circuit from  FIG. 6  showing the pixels, the pixel columns, and the pixel units respectively.  FIG. 8A  shows the driving circuit of the present invention in which every three adjacent pixels are coupled to the same data line, as shown in  FIG. 6 . Referring to  FIG. 8B , and taking the adjacent pixels P 1  (m,n), P 2 (m,n), and P 3 (m,n) as an example, the method used for inputting data signals into the corresponding pixels of the color display panel is to input the data signal for showing red into pixel P 1 (m,n), the data signal for green into pixel P 2 (m,n), and the data signal for blue into pixel P 3 (m,n). All other pixels in the same column with pixel P 1  (m,n) are input with data signals for showing red; the pixel column is thus called the red pixel column RPC 1 . In the same manner, all other pixels in the same column with pixel P 2 (m,n) are input with the data signals for showing green; the pixel column is thus called the green pixel column GPC 1  and all other pixels in the same column with pixel P 3 (m,n) are input with the data signals for showing blue; the pixel column is thus called the blue pixel column BPC 1 . Following the same order, the pixel column which includes pixel P 1  (m,n+1) is for displaying red; the pixel column which includes pixel P 2 (m,n+1) is for displaying green; and the pixel column which includes pixel P 3 (m,n+1) is for displaying blue. Therefore, these three adjacent pixel columns are called red pixel column RPC 2 , green pixel column GPC 2 , and blue pixel column BPC 2  respectively. In  FIG. 8C , pixel unit PU 1  includes three adjacent pixels: P 1  (m,n), P 2 (m,n), and P 3 (m,n). Since pixels P 1 (m,n) P 2 (m,n), and P 3 (m,n) are for displaying red, green, and blue respectively, the display color of pixel unit PU 1  can be controlled by controlling the luminance of these three pixels. In the same manner, the display color of pixel unit PU 2  can be controlled by controlling the luminance of pixels P 1  (m,n+1), P 2 (m,n+1), and P 3 (m,n+1) respectively. Every three adjacent pixels are grouped into a pixel unit for displaying color, as shown in  FIG. 8C . 
   Taking pixel P 1  (m,n) of pixel unit PU 1  and pixel P 1  (m,n+1) of pixel unit PU 2  in  FIG. 8C  as an example, both pixels P 1  (m,n) and P 1  (m,n+1) are for displaying red. However, since the switching device of pixel P 1 (m,n) and pixel P 1  (m,n+1) are identical, the degree of feed-through effect and the aperture ratio of these two pixels are substantially the same. Therefore, the luminance of these two pixels P 1  (m,n) and P 1  (m,n+1) can be substantially the same when the magnitude of the data signals input to these two pixels P 1  (m,n) and P 1 (m,n+1) respectively, are identical. In the same manner, the luminance of the pixel of pixel unit PU 1 , which is for displaying green, and the corresponding pixel of pixel unit PU 2  and the pixel of pixel unit PU 1 , which is for displaying blue, and the corresponding pixel of pixel unit PU 2  may be the same when the respective data signals input are of the same magnitude. Therefore, the odd-even problem can be improved when the data signals input into all pixels in the display panel have the same magnitude, thus improving display performance. 
   The display apparatus with the driving circuit in accordance with the invention has the following advantages. First, a reduced number of data lines are required. Therefore, the pitch between adjacent data lines can be increased. It is easier to connect all data lines to the corresponding outer leads of the tape carrier packages. Also, since the number of data lines is decreased, the aperture ratio of the display panel is increased. Second, the switching devices of corresponding pixels of all pixel units are identical, the degree of feed-through effect and the aperture ratio of these corresponding pixels are substantially the same and the odd-even line problem can be improved. If the pixels are set in the mirror image form, the odd-even problem can be further improved. 
   While the invention has been described by way of example and in terms of the preferred embodiment, it is to be understood that the invention is not limited to the disclosed embodiment. On the contrary, it is intended to cover various modifications and similar arrangements and procedures, and the scope of the appended claims therefore should be accorded the broadest interpretation so as to encompass all such modifications and similar arrangements and procedures.