Abstract:
A method of displaying text on multiple display devices. The multiple display devices include a master device with a master display and at least one slave device with a slave display. The method includes establishing communication between the master device and the slave device, dividing the text into a first part and a second part based on a first display dimension of the master display and a second display dimension of the slave display, transmitting the second part to the slave device, and simultaneously displaying the first part on the master display and the second part on the slave display. For each individual row of text that is displayed on both the master display and the slave display, a fraction of text is displayed on the master display and a remaining fraction of text is displayed on the slave display.

Description:
BACKGROUND OF INVENTION  
       [0001]     1. Field of the Invention  
         [0002]     The present invention relates to display devices, and more specifically, to a method for utilizing multiple display devices to display a single text.  
         [0003]     2. Description of the Prior Art  
         [0004]     The popularity of electronic devices and portable computing devices allows people to access information anywhere. Electronic devices such as mobile phones, personal digital assistants (PDAs), and other personal computing devices can be used to read documents in any location.  
         [0005]     Please refer to  FIG. 1 .  FIG. 1  is a diagram of a mobile phone  10  according to the prior art. The mobile phone  10  contains a display  12  such as a liquid crystal display (LCD) that is used to display text and images. As shown in  FIG. 1 , the display  12  currently shows a text message. Unfortunately, the dimensions of the display  12  limit the amount of text that can be displayed at one time. Typical displays have a limited number of columns and rows that can be used to display text characters. While text documents can still be read on the display  12  of the mobile phone  10 , the limited dimensions of the display  12  mean that a user of the mobile phone  10  has to constantly scroll down to read a next screen of text. As an example,  FIG. 1  depicts the display  12  as only being able to show the words, “The quick brown fox jumps over the lazy dog.” 
         [0006]     Although  FIG. 1  shows a mobile phone  10 , the small dimensions of the display  12  of the mobile phone  10  are representative of the problems of small displays used on other electronic devices such as PDAs.  
       SUMMARY OF INVENTION  
       [0007]     It is therefore an objective of the claimed invention to provide a method of displaying text on displays of multiple electronic devices.  
         [0008]     According to the claimed invention, a method of displaying text on multiple display devices is proposed. The multiple display devices include a master device with a master display and at least one slave device with a slave display. The method includes establishing communication between the master device and the slave device, dividing the text into a first part and a second part based on a first display dimension of the master display and a second display dimension of the slave display, transmitting the second part to the slave device, and simultaneously displaying the first part on the master display and the second part on the slave display. For each individual row of text that is displayed on both the master display and the slave display, a fraction of text is displayed on the master display and a remaining fraction of text is displayed on the slave display.  
         [0009]     It is an advantage of the claimed invention that multiple display devices can be used to show a text document for allowing a large amount of text to be viewed at one time.  
         [0010]     These and other objectives of the claimed invention will no doubt become obvious to those of ordinary skill in the art after reading the following detailed description of the preferred embodiment, which is illustrated in the various figures and drawings.  
     
    
     BRIEF DESCRIPTION OF DRAWINGS  
       [0011]      FIG. 1  is a diagram of a mobile phone according to the prior art.  
         [0012]      FIG. 2  is a diagram of a master device and a slave device connected together to display a single text document.  
         [0013]      FIG. 3  is a figure of text displayed on a PC console.  
         [0014]      FIG. 4  and  FIG. 5  show pages of text displayed on multiple display devices according to the present invention.  
         [0015]      FIG. 6  is a message sequence chart illustrating commands sent between the master device and the slave device according to the present invention. 
     
    
     DETAILED DESCRIPTION  
       [0016]     Please refer to  FIG. 2 .  FIG. 2  is a diagram of a master device  20  and a slave device  30  connected together to display a single text document. The master device  20  has a master display  22  and the slave device  30  has a slave display  32  for displaying text. Although mobile phones are depicted in  FIG. 2 , the present invention method may be used with any electronic device that contains a display. The present invention is particularly useful for portable electronic devices without a large display such as mobile phones, PDAs, and personal computing devices.  
         [0017]     The master device  20  and the slave device  30  are connected together with a cable  25  to allow communication between the master device  20  and the slave device  30 . The master device  20  and the slave device  30  preferably communicate with a serial connection, although other communication protocols may also be used. In addition, the master device  20  and the slave device  30  may communicate wirelessly instead of using the cable  25 .  
         [0018]     The present invention allows the master display  22  to be used in conjunction with the slave display  32  to display a common text document. As shown in  FIG. 2 , the master display  22  and the slave display  32  show the words, “The quick brown fox jumps over the lazy dog. He then dances around in great joy.” If the master display  22  and the slave display  32  have the same number of columns and rows for displaying text, then half of each row of text is displayed on the master display  22  and the other half of each row of text is displayed on the slave display  32 . As will be shown below, the present invention method can also be used in cases where the dimensions of the master display  22  and the slave display  32  are different from each other. Please note that the master display  22  does not have to be used for displaying a left-hand side portion of the text. It is also possible to switch the position of the master device  20  and the slave device  30  so that the slave display  32  is used to display a left-hand side portion of the text and the master display  22  is used to display a right-hand side portion of the text.  
         [0019]     Please refer to  FIG. 3 .  FIG. 3  is a figure of text displayed on a PC console  40 . The PC console  40  shown has dimensions of X columns and Y rows, which in this case is shown as 80 columns by 18 rows. Standard dimensions for a PC console may be 80 columns by 25 rows, but a smaller size is shown on  FIG. 3  for clarity of illustration. The PC console  40  shown is a simplified version that performs character wrapping, which does not keep whole words together, and simply moves text to the next row whenever the end of a row is reached.  
         [0020]     Please refer to  FIG. 4  and  FIG. 5 .  FIG. 4  and  FIG. 5  show pages of text displayed on multiple display devices according to the present invention.  FIG. 4  illustrates a first combined page of text shown on a first display  50  and a second display  60 . The first display  50  represents either the master display  22  or the slave display  32 , with the second display  60  representing the other of the master display  22  and the slave display  32 . The first display  50  has dimensions of M columns by N rows, which is shown in  FIG. 4  and  FIG. 5  as 40 columns by 20 rows. The second display  60  has dimensions of P columns by Q rows, which is shown in  FIG. 4  and  FIG. 5  as 50 columns by 10 rows.  FIG. 4  and  FIG. 5  illustrate a case of displaying text on the first display  50  and the second display  60  when the dimensions of the first display  50  and the second display  60  are not equal. The case in which the dimensions are equal will naturally follow from understanding this relatively more difficult case. Like the PC console  40  of  FIG. 3 , the first display  50  and the second display  60  shown in  FIG. 4  and  FIG. 5  also perform character wrapping. This means that at the end of the line, whole words are not kept together, and text is simply cut off when the end of a row is reached. Please note, however, that the present invention is not limited to this and, word wrapping in which words are kept together, can also be used according to the wishes of the designer or manufacturer.  
         [0021]     When using a combination of both the first display  50  and the second display  60  to display a text document, it is recommended to line up the top borders of the first display  50  and the second display  60  so that the first row of text is aligned. Although the first display  50  can display more rows than the second display  60 , the smaller row dimension of the first and second displays  50  and  60  will control how many rows of text appear on each page. Therefore, as shown in  FIG. 4  and  FIG. 5 , only ten rows of text are displayed at a time.  
         [0022]     For clarity, two additional labels will be defined for showing how text is divided between the first display  50  and the second display  60 . Let C be equal to the smaller of Q and N (in this case C=Q), where C represents the number of rows that will be used to display text using a combination of the first display  50  and the second display  60 . Let R be equal to the longer of N and Q, minus C (in this case R=N−C), where R represents a remaining number of rows that are not used to display text.  
         [0023]     Once the values of M, N, P, Q, C and R are known, the master device  20  divides the text document into pages of text. This is done by displaying M characters of text on the first display  50  and P characters of text on the second display  60  for each of C rows of text.  
         [0024]     When a user is finished reading the first combined page of text shown on  FIG. 4 , scroll buttons  52  and  62  on either the first display  50  or the second display  60  (or corresponding key buttons on either the master device  20  or the slave device  30 ) may be pressed to scroll down to a second combined page of text that is shown on  FIG. 5 . The scroll buttons  52  and  62  may be used to scroll up or down in a text document. Each time the scroll buttons  52  and  62  are pressed, a new page of text is shown on both the first display  50  and the second display  60 .  
         [0025]     Please refer to  FIG. 6 .  FIG. 6  is a message sequence chart illustrating commands sent between the master device  20  and the slave device  30  according to the present invention. The status of the text display mode is also indicated in a left-hand side of  FIG. 6 .  
         [0026]     Initially, the master device  20  and the slave device  30  are in an original text display mode in which the master display  22  and the slave display  32  are each displaying respective data corresponding to the master device  20  and the slave device  30 . At this time the master device  20  begins serially communicating with the slave device  30  wirelessly or using the cable  25 . The master device  20  then sends command  70  to the slave device  30  for changing the display mode to a connected display mode. The slave device  30  responds with an acknowledgement command  72 .  
         [0027]     Next, the connected display mode is initialized. The master device  20  sends command  74  to the slave device  30  to ask the slave device  30  for the dimensions of the slave display  32 . The slave device  30  responds by sending the dimensions of the slave display  32  in command  76 . The master device  20  may also indicate the dimension of the master display  22  to the slave device selectively. The master device  20  then calculates the display ratio that will be used in the connected display mode and sends the calculated display ratio to the slave device  30  in command  78 . The display ratio indicates how many characters of text will be displayed on the master display  22  and the slave display  32  for each row of text. The master device  20  only needs to send the dimensions that apply to the slave display  32  to the slave device  30 , and can also optionally send the dimensions that apply to the master display  22 . In this way, the slave device is made aware of how many characters of text it will display for each row of text. In response to command  78 , the slave device  30  responds with an acknowledgement command  80 .  
         [0028]     At this time the master device  20  and the slave device  30  are in connected display mode. The master device  20  sends text data in command  82  to the slave device  30 , and text data is simultaneously displayed on the master display  22  and the slave display  32 . This continues until the master device  20  sends a termination command  84  to the slave device  30 , which switches the master device  20  and the slave device  30  back to the original text display mode.  
         [0029]     The present invention method is not limited to being used in just two display devices. Using three or more display devices to display text in combination with each other is also in the spirit of the present invention. In this case, the master device simply needs to know the dimensions of each of the slave displays for dividing the text document among the multiple displays.  
         [0030]     In contrast to the prior art, the present invention method utilizes multiple display devices to display a text document, thereby allowing a large amount of text to be viewed at one time. Any size display devices can be used, and the display devices do not need to have the same dimensions.  
         [0031]     Those skilled in the art will readily observe that numerous modifications and alterations of the device may be made while retaining the teachings of the invention. Accordingly, the above disclosure should be construed as limited only by the metes and bounds of the appended claims.