Patent Publication Number: US-2011050671-A1

Title: Non-volatile display module and non-volatile display apparatus

Description:
CROSS REFERENCE TO RELATED APPLICATIONS 
     This Non-provisional application claims priority under 35 U.S.C. §119(a) on Patent Application No(s). 098128817 filed in Taiwan, Republic of China on Aug. 27, 2009, the entire contents of which are hereby incorporated by reference. 
    
    
     BACKGROUND OF THE INVENTION 
     1. Field of Invention 
     The present invention is related to a display module and apparatus, and in particular, to a non-volatile display module and apparatus. 
     2. Related Art 
     The display apparatuses have been sufficiently improved from the traditional CRT display apparatuses. For example, the LCD apparatus, OLED display apparatus, and E-paper display apparatus are developed recently, and they all have the advantages of reduced volume and weight. Thus, they can be widely applied to the communication products, information products and consumer electronics products. 
     As shown in  FIG. 1 , a conventional display apparatus, such as an LCD display apparatus, includes an LCD display module  1 , which has a LCD panel  11 , a data driving circuit  12 , and a scan driving circuit  13 . The data driving circuit  12  is electrically connected with the LCD panel  11  through a plurality of data lines D 11  to D 1n , and the scan driving circuit  13  is electrically connected with the LCD panel  11  through a plurality of scan lines S 11  to S 1m . 
     As shown in  FIG. 2 , the data driving circuit  12  includes a shift register unit  122 , a primary latch unit  123 , a secondary latch unit  124 , and a level shifter unit  125 . The shift register unit  122  is electrically connected with the primary latch unit  123 , and the secondary latch unit  124  is electrically connected with the primary latch unit  123  and the level shifter unit  125 . 
     With reference to  FIG. 2  and  FIG. 3 , the shift register unit  122  can generate shift register signals A 11  to A 1n , according to a start pulse signal A 01  and a clock signal CK, and then outputs the shift register signals A 11  to A 1n  to the primary latch unit  123 . 
     The primary latch unit  123  receives an image signal A 02  according to the shift register signals A 11  to A 1n . The image signal A 02  includes a plurality of image data and is stored in the primary latch unit  123 . The secondary latch unit  124  retrieves the image signal A 02  according to a latch enable signal A 03 . The level shifter unit  125  transforms the image signal A 02 , which is stored in the secondary latch unit  124 , into a plurality of display signals, which are transmitted to the LCD panel  11  through the data lines D 11  to D 1n  correspondingly for displaying an image. 
     Due to the progress of technologies in this field, the non-volatile material, such as electrophoresis material, electrowetting material, cholesteric liquid crystal, or nematic liquid crystal, is successfully applied in the display apparatus. Generally speaking, the display apparatus including the non-volatile material has the features of small size and portable. If the above-mentioned data driving circuit  12  and scan driving circuit  13  can be integrated so as to reduce the amount of the components, the display apparatus can be manufactured with smaller or thinner size, or less weight, thereby decreasing the manufacturing cost. 
     Therefore, it is an important subject to provide a non-volatile display module and apparatus that have reduced amount of components. 
     SUMMARY OF THE INVENTION 
     In view of the foregoing, an objective of the present invention is to provide a non-volatile display module and apparatus that have reduced amount of components. 
     To achieve the above, the present invention discloses a non-volatile display module including a display panel and a driving circuit. The display panel includes a substrate disposed with at least one scan line, at least one data line and at least one thin film transistor (TFT). The TFT is located at an interlaced area of the scan line and the data line. The driving circuit includes a memory unit, a voltage level generating unit and a voltage level selecting unit. The memory unit receives and stores at least one image control signal in accordance with a clock signal. The voltage level generating unit generates a plurality of voltage-level signals. The voltage level selecting unit is electrically connected with the scan line, the data line, the memory unit and the voltage level generating unit. The voltage level selecting unit outputs one of the voltage-level signals to the scan line or the data line in accordance with the image control signal. 
     In addition, the present invention also discloses a non-volatile display apparatus including a non-volatile display module. The non-volatile display module includes a display panel and a driving circuit. The driving circuit includes a memory unit, a voltage level generating unit, and a voltage level selecting unit. The memory unit receives at least one image control signal in accordance with a clock signal. The voltage level generating unit generates a plurality of voltage-level signals. The voltage level selecting unit is electrically connected with the scan line, the data line, the memory unit and the voltage level generating unit. The voltage level selecting unit outputs one of the voltage-level signals to the scan line or the data line in accordance with the image control signal. 
     As mentioned above, the non-volatile display module and apparatus of the invention have a driving circuit, which includes a memory unit, a voltage level generating unit and a voltage level selecting unit, for processing the signals transmitted through the scan line and data line, thereby generating the displayed image. Compared with the prior art, the non-volatile display apparatus of the invention can not only integrate the conventional separated scan driving circuit and data driving circuit, but also use the driving circuit with simpler structure to process the signals transmitted through the scan line and the data line. Thus, the non-volatile display module and apparatus of the present invention can be manufactured with reduced amount of components, thereby decreasing the manufacturing cost. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       The invention will become more fully understood from the detailed description and accompanying drawings, which are given for illustration only, and thus are not limitative of the present invention, and wherein: 
         FIG. 1  is a schematic diagram of the conventional display apparatus; 
         FIG. 2  is a schematic diagram showing the data driving circuit of the conventional display apparatus; 
         FIG. 3  is a timing chart of the data driving circuit of the conventional display apparatus; 
         FIG. 4  is a schematic diagram of a non-volatile display apparatus according to an embodiment of the invention; 
         FIG. 5 ,  FIG. 6  and  FIG. 7  are schematic diagrams respectively showing the circuit connection structures of the multiplexer and voltage level generating unit of the display apparatus of  FIG. 4 ; and 
         FIG. 8  is a timing chart of the voltage level signal outputted by the voltage level generating unit of  FIG. 7 . 
     
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
     The present invention will be apparent from the following detailed description, which proceeds with reference to the accompanying drawings, wherein the same references relate to the same elements. 
     A non-volatile display apparatus means it has at least two stable states, so that it can be lasting in the stable state for several tens of milliseconds (ms) after removing the power source. Besides, the optical modulation material of the display apparatus may include electrophoresis solution, electrowetting material, cholesteric liquid crystal, or nematic liquid crystal. 
     With reference to  FIG. 4 , a non-volatile display apparatus according to an embodiment of the invention includes a non-volatile display module  2 , which includes a display panel  3  and a driving circuit  4 . In the embodiment, the driving circuit  4  is electrically connected with the display panel  3  through a plurality of data lines D 21  to D 2n  and a plurality of scan lines S 21  to S 2m . 
     The display panel  3  includes a substrate  31 , at least one scan line, at least one data line, and at least one thin film transistor TFT. The thin film transistor TFT is located at an interlaced area of the scan line and the data line, and is electrically connected to an electrode. Herein, the interlaced as well as the thin film transistor TFT is called a pixel unit, and the pixel units can be arranged in a one-dimension array or a two-dimension array. In this embodiment, the display panel  3  includes a plurality of pixel units  3   11  to  3   mn  for example, and they are arranged in a two-dimension array. The scan lines S 21  to S 2m  and the data lines D 21  to D 2n  are crossly disposed on the display panel  3  to form a plurality of interlaced areas, which are disposed corresponding to the pixel units  3   11  to  3   mn . 
     The driving circuit  4  includes a memory unit  41 , a voltage level generating unit  42 , and a voltage level selecting unit  43 . The voltage level selecting unit  43  is electrically connected with the scan lines S 21  to S 2m , the data lines D 21  to D 2n , the memory unit  41  and the voltage level generating unit  42 . 
     The memory unit  41  has a shift register  411  and a latch  412 , which are electrically connected with each other, and the voltage level selecting unit  43  has at least one multiplexer. In this embodiment, the voltage level selecting unit  43  has a plurality of multiplexers  431 , each of which is electrically connected with the memory unit  41 , the voltage level generating unit  42  and the corresponding one of the scan lines S 21  to S 2m  or the data lines D 21  to D 2n . 
     When the driving circuit  4  is enabled, the shift register receives an image control signal A 21  according to a clock signal CK. In this case, the image control signal A 21  includes a plurality of first driving signals A 31  to A 3m  and a plurality of second driving signals A 41  to A 4n . 
     The latch  412  receives the first driving signals A 31  to A 3m  and the second driving signals A 41  to A 4n  according to a latch signal A 51 , and then transmits them to the voltage level selecting unit  43 . In more detailed, the shift register  411  receives the image control signal A 21  in series, and the latch  412  transmits the first driving signals A 31  to A 3m  and the second driving signals A 41  to A 4n  to the voltage level selecting unit  43  in parallel. 
     To simplify the following description, the voltage level selecting unit  43  cooperating with the voltage level generating unit  42 , the multiplexer  431  and the scan line S 21  for transmitting one of the voltage level signals to the scan line S 21  according to the image control signal A 21  will be illustrated hereinbelow. 
     Referring to  FIG. 5 , the voltage level generating unit  42  outputs four voltage level signals A 61  to A 64  to the multiplexer  431 . In this case, the voltage level generating unit  42  is, for example, a DC/DC voltage-level translator, and the voltage level signals A 61  to A 64  are all DC voltage signals (e.g. 30V, −10V, 20V and −5V). 
     In this case, the multiplexer  431  is disposed corresponding to the scan line S 21 , so that the image control signal A 21  herein is the first driving signal A 31 . The multiplexer  431  can transmit one of the voltage level signals A 61  to A 64  to the scan line S 21  according to the first driving signal A 31  for determining the voltage level of the scan signal transmitted by the scan line S 21 . When the scan line S 21  transmits the scan signal with the voltage level of 30V or 20V, the transistor of the pixel unit  3   11  can be enabled; otherwise, when the scan line S 21  transmits the scan signal with the voltage level of −10V or −5V, the transistor of the pixel unit  3   11  can be disabled. 
     To be noted that the voltage level generating unit  42  generates only four voltage level signals A 61  to A 64  is for illustration only, and those skilled in the art should know that the output, such as the amount and levels of the outputted signals, of the voltage level generating unit  42  can be varied according to the demands. 
     In addition, part of the multiplexers  431  are electrically connected with the scan line S 21 , and the other part of the multiplexers  431  are electrically connected with the data lines D 21  to D 2n . To simplify the following description, the voltage level selecting unit  43  cooperating with the voltage level generating unit  42 , the multiplexer  431  and the data line D 21  for transmitting one of the voltage level signals to the data line D 21  according to the image control signal A 21  will be illustrated hereinbelow. 
     Referring to  FIG. 6 , the voltage level generating unit  42  outputs four voltage level signals A 61  to A 64  to the multiplexer  431 . In this case, the voltage level signals A 61  to A 64  are all DC voltage signals with the voltage levels of, for example, 30V, −10V, 20V and −5V. 
     In this case, the multiplexer  431  is disposed corresponding to the data line D 21 , so that the image control signal A 21  herein is the second driving signal A 41 . The multiplexer  431  can transmit one of the voltage level signals A 61  to A 64  to the data line D 21  according to the second driving signal A 41  for determining the voltage level of the image signal transmitted by the data line D 21 . When the transistor of the pixel unit  3   11  is enabled, the image signal transmitted by the data line D 21  can be written into the pixel unit  3   11 , and the voltage level (e.g. 30V, −10V, 20V, or −5V) of the image signal can control the gray level of the displayed image. 
     As mentioned above, the voltage level signals A 61  to A 64  are transmitted from the voltage level generating unit  42  to the multiplexer  431  through different output terminals or wires. Alternatively, as shown in  FIG. 7 , the voltage level signals A 61  to A 64  can be transmitted from the voltage level generating unit  42   a  to the multiplexer  431   a  through the same output terminal o wire. Referring to  FIG. 8 , the voltage level generating unit  42   a  can output the voltage level signals A 61  to A 64  at different timings, respectively, to the multiplexer  431   a . For example, the voltage level signals A 61  is outputted at the timing T 1 , the voltage level signals A 62  is outputted at the timing T 2 , the voltage level signals A 63  is outputted at the timing T 3 , and the voltage level signals A 64  is outputted at the timing T 4 . After that, the voltage level signals A 61  to A 64  are repeatedly outputted. To be noted, the output order (or the values order of the voltage levels) of the voltage level signals A 61  to A 64  is not limited to the above example. 
     In practice, in order to efficiently decrease the total volume, at lease one part of the driving circuit  4  is manufactured by a single crystalline process and formed in an IC chip. Alternatively, at lease one part of the driving circuit  4  is manufactured by a polycrystalline process or an amorphous process and formed on the same substrate as the pixel units  3   11  to  3   mn . In this case, the amorphous process can be an amorphous silicon thin-film-transistor process or an organic thin-film-transistor process. Of course, different manufacturing processes can be used. For example, the memory unit  41  can be formed on an IC chip by a single crystalline semiconductor process, the voltage level generating unit  42  and the voltage level selecting unit  43  can be formed on the same substrate as the pixel units  3   11  to  3   mn  by a polycrystalline process or an amorphous process. In brief, the memory unit  41 , the voltage level generating unit  42  and the voltage level selecting unit  43  can be all configured in an integrated circuit; otherwise, only the memory unit  41  and the voltage level selecting unit  41  are configured in an integrated circuit. Herein, the integrated circuit can be a single crystalline integrated circuit. 
     In summary, the non-volatile display module and apparatus of the invention have a driving circuit, which includes a memory unit, a voltage level generating unit and a voltage level selecting unit, for processing the signals transmitted through the scan line and data line, thereby generating the displayed image. Compared with the prior art, the non-volatile display apparatus of the invention can not only integrate the conventional separated scan driving circuit and data driving circuit, but also use the driving circuit with simpler structure to process the signals transmitted through the scan line and the data line. Thus, the non-volatile display module and apparatus of the present invention can be manufactured with reduced amount of components, thereby decreasing the manufacturing cost. 
     Although the invention has been described with reference to specific embodiments, this description is not meant to be construed in a limiting sense. Various modifications of the disclosed embodiments, as well as alternative embodiments, will be apparent to persons skilled in the art. It is, therefore, contemplated that the appended claims will cover all modifications that fall within the true scope of the invention.