Patent Publication Number: US-2006007053-A1

Title: Multi-panel liquid crystal display and method for driving same

Description:
This application claims the benefit of Taiwan application Serial No. 93116738, filed Jun. 10, 2004, the subject matter of which is incorporated herein by reference.  
     BACKGROUND OF THE INVENTION  
      1. Field of the Invention  
      The invention relates in general to a liquid crystal display, and more particularly to a multi-panel liquid crystal display and a method for driving the same.  
      2. Description of the Related Art  
      Because liquid crystal displays (LCDs) have the advantages of thin, light, and low electromagnetic radiation, it is gradually and widely used recently.  FIG. 1  is an architecture diagram showing a conventional LCD. The LCD  100  includes an interface circuit  101  and a LCD module  102 . The interface circuit  101  receives an external image data, such as that outputted from a personal computer, converts the image data into a digital image data, and outputs the digital image data. The LCD module  102  further displays a frame according to the digital image data.  
      The external image data may be, for example, a digital DVI data, an analog S video data, a composite video data, a D-sub video data, or the like. The interface circuit  101  includes a scaler IC (not shown) for adjusting the magnitude of the external image data and then outputting the digital image data.  
      The LCD module  102  includes a control circuit  110  and a panel module  120 . The control circuit  110  drives the panel module  120  to display the frame according to the digital image data. The control circuit  110  includes a timing controller  112 , a color corrector  114 , and a DC-DC power converter  116 . The panel module  120  includes a data driver  122 , a scan driver  124  and a liquid crystal panel  126 .  
      The timing controller  112  receives the digital image data and then outputs the first image data to the data driver  122 . The color corrector  114  outputs color correction parameters, which include, for example, multiple Gamma voltages, to the data driver  122  according to the property of the liquid crystal panel  126 . The DC-DC power converter  116  is for outputting a DC power as the power for the panel module  120 .  
      However, the typical LCD can only display one frame. Multiple LCDs have to be purchased if multiple frames are to be displayed at the same time, and the cost is too high.  
     SUMMARY OF THE INVENTION  
      It is therefore objects of the invention to provide a multi-panel liquid crystal display for displaying the same frame or different frames and a method for driving the same.  
      The invention achieves the above-identified object by providing a multi-panel liquid crystal display (LCD). The LCD includes an interface circuit and a LCD module. The interface circuit is used for receiving a first image data and outputting a second image data. The LCD module includes a control circuit, a first panel module and a second panel module. The control circuit includes a timing controller, a color corrector and a DC-DC power converter. The timing controller is for receiving the second image data and outputting a third image data and a fourth image data according to the second image data. The color corrector is for outputting a first color correction parameter and a second color correction parameter. The DC-DC power converter is for outputting a first DC power and a second DC power. The first panel module is operable under the first DC power, and displays a first frame according to the first color correction parameter and the third image data. The second panel module is operable under the second DC power, and displays a second frame according to the second color correction parameter and the fourth image data.  
      The invention achieves another object by providing a method for driving a multi-panel liquid crystal display (LCD). The method first receives a second image data and outputting a third image data and a fourth image data responsive to the second image data. Then, the method outputs a first color correction parameter and a second color correction parameter. The method also outputs a first DC power and a second DC power. Then, the method displays a first frame responsive to the first color correction parameter and the third image data on a first panel module of the LCD under the first DC power, and displays a second frame responsive to the second color correction parameter and the fourth image data on a second panel module of the LCD under the second DC power.  
      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 THE DRAWINGS  
       FIG. 1  is an architecture diagram showing a conventional LCD.  
       FIG. 2  is an architecture diagram showing a multi-panel LCD according to a preferred embodiment of the invention.  
       FIG. 3  is an architecture diagram showing a multi-panel LCD according to another preferred embodiment of the invention.  
       FIG. 4  is a flow chart of a method for driving a multi-panel LCD. 
    
    
     DETAILED DESCRIPTION OF THE INVENTION  
       FIG. 2  is an architecture diagram showing a multi-panel LCD according to a preferred embodiment of the invention. Referring to  FIG. 2 , the LCD  200  includes an interface circuit  201  and a LCD module  202 . The interface circuit  201  receives a first image data, outputs a second image data to the LCD module  202 , and thus displays a first frame and a second frame.  
      The LCD module  202  includes a control circuit  210 , and panel modules  220  and  230 . The control circuit  210  drives the panel modules  220  and  230  to display the first frame and the second frame, respectively, according to the second image data. The control circuit  210  includes a timing controller  212 , a color correction unit  214  and a DC-DC power converter  216 . Each of the panel modules  220  and  230 , such as the conventional panel module, have a data driver, a scan driver and a liquid crystal panel, which are not illustrated in the drawing of this embodiment.  
      The timing controller  212  receives the second image data and outputs a third image data and a fourth image data according to the second image data. The color corrector  214  outputs a first color correction parameter and a second color correction parameter according to the properties of the panel modules  220  and  230 . The first and second color correction parameters may, for example, have multiple Gamma voltages. The DC-DC power converter  216  outputs a first DC power and a second DC power as the powers for the panel modules  220  and  230 . The panel module  220  is operable under the first DC power and displays the first frame according to the first color correction parameter and the third image data. The panel module  230  is operable under the second DC power and displays the second frame according to the second and fourth color correction parameters.  
      In this embodiment, the third and fourth image data outputted from the timing controller  212  are the same such that the first and second frames displayed by the panel modules  220  and  230  are the same. In addition, the first and second color correction parameters are the same, and the first and second DC powers are also the same. Because the LCD of this embodiment can control the displays of two panel modules using only one control circuit, the manufacturing cost thereof may be reduced. In addition, this embodiment is not limited to the usage of two panel modules. It is also possible to use more than two panel modules.  
       FIG. 3  is an architecture diagram showing a multi-panel LCD according to another preferred embodiment of the invention. Referring to  FIG. 3 , the LCD  300  includes an interface circuit  301  and a LCD module  302 . The interface circuit  301  is for receiving a first image data and outputting a second image data to the LCD module  302  according to the first image data so as to display a first frame and a second frame.  
      The LCD module  302  includes a control circuit  310  and panel modules  320  and  330 . The control circuit  310  drives the panel modules  320  and  330  to display the first frame and the second frame, respectively, according to the second image data. The control circuit  310  includes a timing controller  312 , a color corrector  314  and a DC-DC power converter  316 . Each of the panel modules  320  and  330 , such as the conventional panel module, has a data driver, a scan driver and a liquid crystal panel, which are not illustrated in the drawing of this embodiment.  
      The timing controller  312  receives the second image data and outputs a third image data and a fourth image data responsive to the second image data. The color corrector  314  outputs a first color correction parameter and a second color correction parameter according to the properties of the panel modules  320  and  330 . The first and second color correction parameters may, for example, have multiple Gamma voltages. The DC-DC power converter  316  outputs a first DC power and a second DC power as the powers for the panel modules  320  and  330 . The panel module  320  is operable under the first DC power and displays the first frame responsive to the first color correction parameter and the third image data. The panel module  330  is operable under the second DC power and displays the second frame responsive to the second and fourth color correction parameters.  
      In this embodiment, the timing controller  312  further includes a timing control unit  318  and a timing control unit  319 . The timing control unit  318  outputs the third image data responsive to the second image data so as to control the panel module  320  correspondingly. The timing control unit  319  outputs the fourth image data responsive to the second image data so as to control the panel module  330  correspondingly. The second image data includes two different frame data such that the third image data and the fourth image data are different, and the first and second frames are therefore different. The first and second color correction parameters are the same, and the first and second DC powers are also the same. This embodiment enables the two panel modules to display different frames using one control circuit, so the cost of the LCD may be reduced and the LCD may be used conveniently. In addition, the embodiment is not limited to the usage of two panel modules. It is also possible to use more than two panel modules.  
      In the multi-panel LCD according to each embodiment of the invention, the same control circuit is used to correspondingly control multiple panel modules to display the same frame or different frames. So, the production cost may be reduced and the LCD may be miniaturized.  
       FIG. 4  is a flow chart of a method for driving a multi-panel LCD, having a first panel module, a second panel module and a timing controller, according to a preferred embodiment of the invention. First of all, the second image data is provided to the timing controller in step  410  and then the timing controller outputs the third image data and the fourth image data, responsive to the second image data, in step  420 . Next, a first color correction parameter and a second color correction parameter are provided in step  430  and a first DC power and a second DC power for the first display panel and the second display panel, respectively, are provided in step  440 . Then, step  450  is performed to display a first frame responsive to the first color correction parameter and the third image data on a first panel module under the first DC power. At the same time, step  460  is performed to display a second frame responsive to the second color correction parameter and the fourth image data on a second panel module under the second DC power. The first and second DC powers are the same  
      The above-mentioned driving method can be applied to the LCD module  202  or LCD module  302 . While the method is applied to the LCD  202 , the first and second color correction parameters, the third and fourth image data are the same such that the frames displayed on the first panel module and the second module are substantially the same.  
      While the method is applied to the LCD  302 , the first and second color correction parameters, the third and fourth image data are not the same such that the frames displayed on the first panel module and the second module are substantially different.  
      While the invention has been described by way of example and in terms of preferred embodiments, it is to be understood that the invention is not limited thereto. Rather, 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.