Patent Publication Number: US-2011050544-A1

Title: Image display system including a plurality of electronic paper display devices

Description:
CROSS REFERENCE TO RELATED APPLICATION 
     This application claims priority from Japanese Patent Application No. 2009-193953 filed Aug. 25, 2009. The entire content of this priority application is incorporated herein by reference. 
     TECHNICAL FIELD 
     The present invention relates to an image display system and an image processing device for displaying images on a plurality of electronic paper display devices, and also relates to an electronic paper display device for displaying electronic images thereon. 
     BACKGROUND 
     An electronic paper display device has recently been put to practical use as a portable electronic document viewer. There has also been provided a system that communicably connects between an electronic paper display device and a printing device to establish data communication therebetween. For example, Japanese Patent Application Publication No. 2008-225551 discloses a system in which an image processing device outputs print data, which is to be printed by a printing device, to the printing device, and the printing device converts the print data into display data, which an electronic paper display device can display, and outputs the display data to the electronic paper display device. 
     SUMMARY 
     There is a case where a plurality of electronic paper display devices are juxtaposed side by side to together display a single image, such as a plural-page spread or a single-page worth of image in a magnified size. In other words, the single image consists of a plurality of images each displayed on one of the plurality of electronic paper display devices arranged in a corrected order. In this case, however, a user needs to arrange the plurality of electronic paper display devices in the correct order, and this is inconvenient for the user. 
     In view of the foregoing, it is an object of the invention to provide an image display system, an image processing device, and an electronic paper display device, capable of displaying a single image on a plurality of electronic paper display devices in a simple manner. 
     In order to attain the above and other objects, the invention provides an image display system including a plurality of electronic paper display devices, a first determining unit, and a control unit. Each of the electronic paper display devices displays an image thereon. The first determining unit determines positions of the plurality of electronic paper display devices relative to each other. The control unit controls each of the electronic paper display devices in accordance with the positions determined by the determining unit such that the plurality of electronic paper display devices together display a single image. 
     According to another aspect, the present invention provides an image processing device communicable with a plurality of electronic paper display devices. The image processing device includes a determining unit, a selecting unit, and a sending unit. The determining unit determines positions of the plurality of electronic paper display devices relative to each other. The selecting unit selects one of the plurality of electronic paper display devices for each of plural sets of image data. The sending unit sends each of the plural sets of image data to one of the plurality of electronic paper display devices selected by the selecting unit, so as to enable the plurality of electronic paper display devices to together display a single image. The single image consists of a plurality of partial image corresponding to the plural sets of image data. 
     According to still another aspect, the present invention provides an electronic paper display device including a display unit, a determining unit, and a control unit. The display unit displays an image based on data. The determining unit determines a position of the electronic paper display device relative to another electronic paper display device located adjacent to the electronic paper display device. The control unit controls the display unit to display the image based on the position of the electronic paper display device. The image is a part of a single image, and the single image consisting of the image and another image displayed by the another electronic paper display device. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       The particular features and advantages of the invention as well as other objects will become apparent from the following description taken in connection with the accompanying drawings, in which: 
         FIG. 1  is a block diagram showing electrical configuration of an image display system according to a first embodiment of the invention; 
         FIG. 2  is a block diagram showing electronic configuration of an MFP and an electronic paper display device included in the image display system of  FIG. 1 ; 
         FIG. 3  is a perspective view of the electronic paper display device; 
         FIG. 4  is a plan view of the electronic paper display device displaying an image thereon; 
         FIG. 5  is a plan view of a plurality of electronic paper display devices connected to each other and together displaying a two-page spread; 
         FIG. 6  a plan view of a plurality of electronic paper display devices connected to each other and together displaying a one-page worth of image in a magnified size; 
         FIG. 7  is a flowchart representing a reading/sending process executed in the MFP according to the first embodiment of the invention; 
         FIG. 8  is a flowchart representing a display process executed in the electronic paper display device according to the first embodiment of the invention; 
         FIG. 9  is a flowchart representing a page turn process executed in the electronic paper display device according to the first embodiment of the invention; 
         FIG. 10  is a flowchart representing a first reading/sending process executed in an MFP according to a second embodiment of the invention; and 
         FIG. 11  is a flowchart representing a second reading/sending process executed in the MFP according to the second embodiment of the invention. 
     
    
    
     DETAILED DESCRIPTION 
     Image display systems according to embodiments of the invention will be described while referring to the accompanying drawings wherein like parts and components are designated by the same reference numerals to avoid duplicating description. 
     First Embodiment 
     As shown in  FIG. 1 , an image display system  500  according to a first embodiment of the invention includes a multi function peripheral (MFP)  100  serving as an image processing device, and electronic paper display devices  20 A and  20 B serving as electronic document viewers. The MFP  100  has an image reading function and a printing function. Each electronic paper display device  20 A,  20 B is capable of displaying image data stored in an internal memory thereof. Note that the image display system  500  may alternatively include three or more electronic paper display devices. 
     Each of the MFP  100  and the electronic paper display devices  20 A and  20 B has such wireless communication function as Bluetooth (registered trademark) Thus, when the electronic paper display devices  20 A and  20 B are located within a communicable range of the MFP  100 , the MFP  100  can read data from and write data to the electronic paper display devices  20 A and  20 B. 
     As shown in  FIG. 2 , the MFP  100  includes a CPU  31 , a ROM  32 , a RAM  33 , a non-volatile RAM (NVRAM)  34 , a network interface (I/F)  36 , a wireless communication I/F  38 , an image forming unit  10 , an image reading unit  20 , an operation panel  40 , and a radio frequency identification (RFID) tag reader  50 , all electrically connected via an ASIC  35 . 
     The image forming unit  10  is for forming an image on a paper sheet in one of conventional image forming methods, such as an electrophotographic method or an inkjet method. The image forming unit  10  may be either capable of printing color images or capable of printing monochromatic images only. 
     The image reading unit  20  is for reading an image on an original. The image reading unit  20  has an auto document feeder (ADF) for automatically feeding sheets of original, and is capable of sequentially read images from a plurality of sheets of original. 
     Although not shown in the drawings, the operation panel  40  includes a display unit having a liquid crystal display panel, for example, and various buttons including a start key, a stop key, and numeral keys. The operation panel  40  displays operation status of the MFP  100  or the like, and accepts user&#39;s input. 
     The RFID tag reader  50  detects a RFID tag, and writes data to and reads data from the RFID tag. The RFID tag reader  50  is disposed on the MFP  100  within a range where the RFID tag reader  50  can access a RFID tag attached to an original placed on an original tray (not shown) of the MFP  100 . 
     The ROM  32  stores various control programs for controlling the MFP  100 , various settings, and various initial values. The RAM  33  provides a work area to which the various control programs are read and also a memory area where image data is temporarily stored. 
     The CPU  31  controls the above-mentioned various components of the MFP  100  via the ASIC  35  based on signals from either the control programs read from the ROM  32  or various sensors while storing processed results into either the RAM  33  or the NVRAM  34 . 
     The network I/F  36  is communicable with an external information processing device with a printer driver for the MFP  100  installed thereon through such network as Internet to which the network I/F  36  is connected. The wireless communication I/F  38  is communicable with devices (the electronic paper display devices  20 A and  20 B in this embodiment) having a wireless communication function. Thus, the MFP  100  exchanges data between these devices through either the network I/F  36  or the wireless communication I/F  38 . 
     Next, general configuration of the electronic paper display device  20 A will be described. Note that because configuration of the electronic paper display device  20 B is the same as that of the electronic paper display device  20 A, description thereof will be omitted. 
     As shown in  FIGS. 2 and 3 , the electronic paper display device  20 A includes a display unit  61 , a frame  62 , an operation unit  65 , a wireless communication I/F  66 , a CPU  67 , a memory  68 , and connectors  69 A,  69 B,  69 C, and  69 D. 
     The display unit  61  is a liquid crystal display panel that displays image data stored in the memory  68 . The operation unit  65  includes various buttons including a power button, a page forward button  63 , a page backward button  64 , and the like, and accepts user&#39;s input commanding, for example, to switch screens on the display unit  61 . 
     The memory  68  provides a work area to which various control programs are read and also a memory area for storing image data. The CPU  67  executes various processes based on control programs read from the memory  68  and signals from various sensors to control the above-mentioned various components of the electronic paper display device  20 A while storing the processed results into the memory  68 . 
     The connectors  69 A,  69 B,  69 C, and  69 D are for connecting with other electronic paper display device. More specifically, as shown in  FIG. 4 , one of the connectors  69 A,  69 B,  69 C, and  69 D is disposed on each peripheral edge of the electronic paper display device  20 A, which is in a rectangular shape. In this embodiment, assuming that the electronic paper display device  20 A is placed in an orientation shown in  FIG. 4  such that a longitudinal direction of the electronic paper display device  20 A extends along an up-to-down direction, the connectors  69 A,  69 B,  69 C, and  69 D are disposed on the upper, lower, left, and right edges of the electronic paper display device  20 A, respectively. 
     The connector  69 A is connectable to a connector  69 B of other electronic paper display device, and the connector  69 B is connectable to a connector  69 A of other electronic paper display device. The connector  69 C is connectable to a connector  69 D of other electronic paper display device, and the connector  69 D is connectable to a connector  69 C of other electronic paper display device. 
     Each of the connectors  69 A,  69 B,  69 C, and  69 D is embedded with a sensor for detecting whether other electronic paper display device is connected thereto. Thus, as shown in  FIG. 5 , when the connector  69 D of the electronic paper display device  20 A is connected to the connector  69 C of the electronic paper display device  20 B, for example, then the electronic paper display device  20 A detects that other electronic paper display device is connected to the right side, and the electronic paper display device  20 B detects that other electronic paper display device is connected to the left side. 
     Next, operations of the electronic paper display device  20 A will be described. The electronic paper display device  20 A of the embodiment has three display modes including a basic display mode, a spread display mode, and an enlargement display mode. In the basic display mode, the electronic paper display device  20 A displays one-page worth of image data by itself, as shown in  FIG. 4 . In the spread display mode, the electronic paper display device  20 A is connected to other electronic paper display device(s), and the electronic paper display device  20 A and the other electronic paper display device(s) together display a plural-page spread (plural-page worth of image data). For example, in  FIG. 5 , the electronic paper display devices  20 A and  20 B connected to each other together display a two-page spread. In this case, each electronic paper display device  20 A,  20 B displays one-page worth of image data. In the enlargement display mode, the electronic paper display device  20 A is connected to other electronic paper display device(s), and the electronic paper display device  20 A and the other electronic paper display device(s) together display one-page worth of image data in an enlarged size. For example, in  FIG. 6 , the electronic paper display devices  20 A and  20 B connected to each other together display a one-page worth of image in an enlarged size. In this case, each electronic paper display device  20 A,  20 B displays only part of the one-page worth of image data. 
     In the present embodiment, the MFP  100  has a function to write data to each electronic paper display device. That is, the MFP  100  sends image data to be displayed on the electronic paper display device  20 A,  20 B to the electronic paper display device  20 A,  20 B. The image data may be data that the MFP  100  generates by scanning an original or data that the MFP  100  reads out from an external device (PC or USB memory, for example) connected to the MFP  100 , for example. The electronic paper display device  20 A,  20 B selectively displays image data when requested. 
     Next, a reading/sending process executed in the MFP  100  will be described with reference to the flowchart of  FIG. 7 . The reading/sending process is for reading an original to generate image data and to send the image data to the electronic paper display device  20 A,  20 B, and is executed when a scanning command for scanning an original with the ADF is input while writing to electronic paper display device is specified. 
     In this process, first in S 101  the CPU  31  of the MFP  100  obtains information of each electronic paper display device located within the communicable range of the MFP  100  through a wireless communication. In this example, it is assumed that the electronic paper display devices  20 A and  20 B are in the communicable range, and the CPU  31  obtains information for the electronic paper display devices  20 A and  20 B in S 101 . More specifically, the CPU  31  outputs a request signal to each electronic paper display device  20 A,  20 B. In response to the request signal, each electronic paper display device  20 A,  20 B outputs to the MFP  100  a response signal containing predetermined information (unique identification number allocated to the electronic paper display device  20 A,  20 B, user information, a position of the electronic paper display device  20 A,  20 B relative to other electronic paper display device if the electronic paper display device  20 A,  20 B is connected to the other electronic paper display device, for example). Note that if the CPU  31  receives no response signal, then the CPU  31  controls the operation panel  40  to display an error message indicating no electronic paper display device is available and waits until any response signal is received. 
     Next in S 102  the CPU  31  controls the image reading unit  20  to start auto-feed of one or more sheets of original with the ADF. The sheets of original are fed one at a time starting from a top page. Then in S 103 , the CPU  31  controls the image reading unit  20  to read an original image (one-page worth of image) from a single sheet of original to generate image data, and in S 104  adds a page number to the image data, i.e., generates image data corresponding to the original image with the page number added thereto. 
     Next in S 105 , the CPU  31  sends the image data generated in S 104  to each electronic paper display device  20 A,  20 B from which the CPU  31  has received the response signal in S 101 . That is, if the CPU  31  has received the response signals from a plurality of electronic paper display devices in S 101 , then the CPU  31  outputs the image data to all of the plurality of electronic paper display devices in S 105 . 
     In S 106 , the CPU  31  determines whether or not there is any sheet of original yet to be read. If so (S 106 :Yes), then the CPU  31  returns to S 103  to repeat the process for a next sheet of original. On the other hand, if not (S 106 :No), then the CPU  31  ends the reading/sending process. 
     Next, a display process (corresponding to a first determining unit and a control unit) executed in each electronic paper display device  20 A,  20 B will be described with reference to the flowchart of  FIG. 8 . The display process is for displaying image data and is executed when the electronic paper display device  20 A,  20 B accepts a display command. 
     The display process will be described assuming that the display process is executed in the electronic paper display device  20 A. 
     In this process, first in S 201 , the CPU  67  of the electronic paper display device  20 A attempts to obtain information of other electronic paper display device. More specifically, the CPU  67  determines whether or not each of the connectors  69 A,  69 B,  69 C, and  69 D is connected to other electronic paper display device, based on detection signals from the sensors embedded in the respective connectors  69 A,  69 B,  69 C, and  69 D, and obtains information of other electronic paper display device if any of the connectors  69 A,  69 B,  69 C, and  69 D is connected to the other electronic paper display device. Also, if any of the connectors  69 A,  69 B,  69 C, and  69 D is connected to the other electronic paper display device, then the CPU  67  inquires whether another electronic paper display device is connected to the other electronic paper display device. 
     Then, in S 202  the CPU  67  determines whether or not information of other electronic paper display device is obtained in S 201 . If so (S 202 :Yes), then in S 203  the CPU  67  determines a position of the electronic paper display device  20 A relative to the other electronic paper display device. For example, if the electronic paper display devices  20 A and  20 B are connected to each other as shown in  FIG. 5 , then the CPU  67  recognizes that two electronic paper display devices are connected to each other and that the electronic paper display device  20 A is on the left side, i.e., that the position of the electronic paper display device  20 A is the left. 
     On the other hand, if a negative determination is made in S 202  (S 202 :No), then the CPU  67  skips S 203  and directly proceeds to S 204 . 
     In S 204 , the CPU  67  sets a page-unit number N. If the electronic paper display device  20 A is not connected to any other electronic paper display device, then the CPU  67  sets the page-unit number N to “1”. In this case, the electronic paper display device  20 A is set to the normal display mode. However, if the electronic paper display device  20 A is connected to one or more other electronic paper display devices, then the CPU  67  sets the page-unit number N in accordance with the number of electronic paper display devices connected to each other and the position of the electronic paper display device  20 A. For example, if two electronic paper display devices are connected to each other as shown in  FIG. 5 , then it is determined that these electronic paper display devices are for displaying a two-page spread, and the page-unit number N is set to “2”. If another electronic paper display device (not shown) is connected to one of the electronic paper display devices shown in  FIG. 5 , then it is determined that these three electronic paper display devices are for displaying a three-page spread, then the page-unit number N is set to “3”. In these cases, the electronic paper display device  20 A is set to the spread display mode. If two electronic paper display devices are connected to each other as shown in  FIG. 6 , then it is determined that these two electronic paper display devices are for the enlargement display, and the page-unit number N is set to “1”. In this case, the electronic paper display device  20 A is set to the enlargement display mode. 
     Next in S 205 , the CPU  67  displays an image on the display unit  61 . More specifically, if the electronic paper display device  20 A is in the normal display mode, then the CPU  67  reads image data for a current page from the memory  68  and controls the display unit  61  to display the image data. If the electronic paper display device  20 A is in the spread display mode, then the CPU  67  reads image data of a page number corresponding to the position of the electronic paper display device  20 A from the memory  68  and controls the display unit  61  to display the image data. If the electronic paper display device  20 A is in the enlargement display mode, then the CPU  67  extracts part of image data of a current page corresponding to the position of the electronic paper display device  20 A and controls the display unit  61  to display the extracted part of the image data. Then, the CPU  67  ends the display process. 
     According to the display process of the embodiment, when a plurality of electronic paper display devices are connected to each other, a single image is displayed on the plurality of electronic paper display devices in accordance with connection state of the electronic paper display devices. Note that in this embodiment the single image means an image consisting of a plurality of images arranged in a correct order. 
     In this embodiment, the display command that triggers the execution of the display process is generated when main power of the electronic paper display device  20 A is turned ON or when image data to be displayed is selected. The display command is also generated when connection between electronic paper display devices is interrupted or when any electronic paper display device is newly connected. That is, the displayed content is changed in association with change in the connection state of electronic paper display devices. Note that the electronic paper display device stores the page number that the electronic paper display device currently displays, and changes contents to display based on the stored page number when the connection state is changed. 
     Next, a page turn process (corresponding to a control unit) executed in the electronic paper display device  20 A,  20 B will be described with reference to the flowchart of  FIG. 9 . The page turn process is executed when either the page forward button  63  or the page backward button  64  ( FIG. 3 ) is pressed. The page turn process will be described next, assuming that the page turn process is executed in the electronic paper display device  20 A. 
     In this process, first in S 221  the CPU  67  obtains the page number that the electronic paper display device  20 A is currently displaying, and in S 222  obtains the page-unit number N. Note that the process of S 222  may be performed before the process of S 221 . 
     Next in S 223  the CPU  67  determines whether or not the button that has been pressed is the page forward button  63 . If so (S 223 :Yes), then in S 224  the CPU  67  increments the current page number by the page-unit number N, and controls the display unit  61  to display image data of the incremented page number. Then, the CPU  67  ends the page turn process. 
     On the other hand, if the button that has been pressed is the page backward button  64  (S 223 :No), then in S 225  the CPU  67  decrements the current page number by the page-unit number N, and controls the display unit  61  to display image data of the decremented page number. Then, the CPU  67  ends the page turn process. 
     In this manner, according to the page turn process of the invention, the page is turned in accordance with the connection state even when a plurality of electronic paper display devices are connected to each other. 
     Note that the page turn process is also executed in the electronic paper display device  20 A when either the page forward button  63  or the page backward button  64  of other electronic paper display device connected to the electronic paper display device  20 A is pressed. That is, the electronic paper display device  20 A turns the page when page is turned in other electronic paper display device connected thereto. For example, if either the page forward button  63  or the page backward button  64  of the electronic paper display device  20 A is pressed while the electronic paper display device  20 A is connected to the electronic paper display device  20 B as shown in  FIG. 5 , then the electronic paper display device  20 A outputs to the electronic paper display device  20 B a signal indicating that either the page forward button  63  or the page backward button  64  is pressed. Then, the electronic paper display device  20 B executes the page turn process upon receiving the signal. Thus, it is possible to remove a burden on a user in having a plurality of electronic paper display devices connected to each other display a right combination of images when turning the page. 
     Second Embodiment 
     Next, a second embodiment of the invention will be described. In the above-described first embodiment, the MFP  100  sends the same image data to each electronic paper display device  20 A,  20 B, and the electronic paper display device  20 A,  20 B displays part of the image data corresponding to the position thereof. However, in this embodiment, the MFP  100  detects the connection state of the electronic paper display devices  20 A and  20 B and sends different image data to each electronic paper display device  20 A,  20 B. 
     More specifically, in this embodiment, a first reading/sending process (corresponding to a first determining unit, a control unit, and a second determining unit) shown in  FIG. 10  and a second reading/sending process (corresponding to a first determining unit and a control unit) shown in  FIG. 11  are executed in the MFP  100  instead of the reading/sending process shown in  FIG. 7 . The first and second reading/sending processes are executed when the scanning command is input while writing to electronic paper display device is specified, but the first reading/sending process is executed if the spread display mode is selected, and the second reading/sending process is executed if the enlargement display mode is selected. That is, in this embodiment, a user specifies one of the spread display mode and the enlargement display mode before the user inputs the scanning command. 
     First, the first reading/sending process will be described with reference to the flowchart of  FIG. 10 . Note that processes that are the same as those of  FIG. 7  will be assigned with the same step numbers. Also, in this embodiment, a RFID sheet attached with a RFID tag is used as a first sheet of original, and the RFID tag stores at least information identifying a text direction, i.e., whether an original text is written vertically or horizontally and/or an orientation (portrait or landscape) of original. 
     In this process, first in S 121 , the CPU  31  wirelessly communicates with any electronic paper display device (electronic paper display devices  20 A and  20 B, in this embodiment) in the communication range of the MFP  100  and obtains information from each electronic paper display device  20 A,  20 B. That is, the CPU  31  outputs the request signal to each electronic paper display device  20 A,  20 B, and the electronic paper display device outputs a response signal to the MFP  100 . The response signal includes at least position information indicating a position of the electronic paper display device  20 A,  20 B. 
     For example, when the electronic paper display devices  20 A and  20 B are connected to each other as shown in  FIG. 5 , then the electronic paper display device  20 A outputs a response signal indicating that other electronic paper display device (the electronic paper display device  20 B) is connected to the right, and the electronic paper display device  20 B outputs a response signal indicating that other electronic paper display device (the electronic paper display device  20 A) is connected to the left. 
     Then, in S 122 , the CPU  31  determines the position of each electronic paper display device  20 A,  20 B based on the information included in the response signal. Next, in S 102 , the CPU  31  controls the image reading unit  20  to start feeding one or more sheets of original with the ADF. In S 123 , the CPU  31  reads information from a RFID tag attached to the first sheet of original, and determines the text direction based on the information. Note that if the CPU  31  fails to read information from the RFID tag, then the CPU  31  determines a default text direction. 
     In S 103 , the CPU  31  controls the image reading unit  20  to read an image (one-page worth of image) on a single sheet of original to generate image data, and in S 104  adds a page number to the image data. 
     In S 124 , the CPU  31  selects an electronic paper display device to which the image data is output, based on the text direction determined in S 103  and the position of each electronic paper display device  20 A,  20 B determined in S 122 . For example, if the electronic paper display devices  20 A and  20 B are connected to each other as shown in  FIG. 5 , and if the text direction is a horizontal direction, then the electronic paper display device  20 A on the left side is selected for a first page, and the electronic paper display device  20 B on the right side is selected for a following page. On the other hand, if the electronic paper display devices  20 A and  20 B are connected as shown in  FIG. 5 , but if the text direction is a vertical direction, then the electronic paper display device  20 B is selected for the first page, and the electronic paper display device  20 A is selected for the following page. 
     Next, in S 125 , the CPU  31  sends the image data generated in S 104  to the electronic paper display device selected in S 124 . In S 106 , the CPU  31  determines whether or not there is any sheet of original yet to be read. If so (S 106 :Yes), then the CPU  31  returns to S 103  to repeat the process for the next sheet of original. On the other hand, if not (S 106 :No), then the CPU  31  ends the first reading/sending process. 
     According to the first reading/sending process described above, only image data corresponding to an electronic paper display device is sent to the electronic paper display device. When each electronic paper display device displays corresponding image data, then a plural-page spread is displayed as shown in  FIG. 5 , for example. In other words, a plurality of electronic paper display devices displaying corresponding image data together display a single plural-page spread. Because only image data to be displayed on an electronic paper display device is sent to the electronic paper display device, the memory  68  of the electronic paper display device can be saved. 
     Next, the second reading/sending process will be described with reference to the flowchart of  FIG. 11 . 
     Because the processes in S 121 , S 122 , and S 102  are the same as those of  FIG. 10 , description thereof will be omitted. In S 143 , the CPU  31  reads information from a RFID tag attached to the first sheet of original, and determines the orientation (portrait or landscape) based on the information. Note that if the CPU  31  fails to read information from the RFID tag, then the CPU  31  determines a default orientation. 
     In S 103 , the CPU  31  controls the image reading unit  20  to read an image (one-page worth of image) on a single sheet of original to generate image data, and in S 104  adds a page number to the image data. 
     In S 144 , the CPU  31  divides the image data (generates plural sets of divided image data) in accordance with the orientation determined in S 143  and the position of each electronic paper display device  20 A,  20 B deter mined in S 122 . For example, if the electronic paper display devices  20 A and  20 B are connected to each other as shown in  FIG. 6 , and if a display orientation needs to be rotated by 90 degrees, then the CPU  31  rotates a scanned image by 90 degrees and then divides the scanned image into right and left. Then, in S 145 , the CPU  31  selects one electronic paper display device for each set of the divided image data. 
     In S 146 , the CPU  31  sends one of plural sets of the divided image data to each electronic paper display device selected in S 145 . In S 106 , the CPU  31  determines whether or not there is any sheet of original yet to be read. If so (S 106 :Yes), then the CPU  31  returns to S 103  to repeat the process for the next sheet of original. On the other hand, if not (S 106 :No), then the CPU  31  ends the second reading/sending process. 
     According to the second reading/sending process of the present embodiment, only image data (divided image data) to be displayed on an electronic paper display device is sent to the electronic paper display device. When each electronic paper display device displays the corresponding divided image data, then a single-page worth of image is displayed in an enlarged size, as shown in  FIG. 6 , for example. In other words, a plurality of electronic paper display devices displaying corresponding divided image data together display a single-page worth of image data. Because the divided image data is sent to the electronic paper display device from the MFP  100 , it is unnecessary for the electronic paper display device to divide image data (or extract corresponding part of image data), reducing a burden on the electronic paper display device. 
     Note that in this second embodiment the text direction and the orientation are determined based on the information stored on the RFID tag. However, the MFP  100  may instead prompt a user to specify the text direction or the orientation before starts reading an original. Alternatively, the MFP  100  may automatically determine the text direction by an optical character reader (OCR) having a function to optically read characters on an original and to recognize the characters by pattern collation. 
     Effects 
     As described above, according to the first and second embodiments of the invention, each electronic paper display device ( 20 A,  20 B) recognizes the position thereof when connected to other electronic paper display device, and each electronic paper display device displays image data corresponding to the position. As a result, a complete (single) image is automatically displayed on the plurality of electronic paper display devices connected to each other. Thus, it is unnecessary for a user to correctly arrange the electronic paper display devices to correctly display a single image thereon, because an image displayed on each electronic paper display device is automatically determined based on the position of the electronic paper display device. Thus, a single image can be correctly displayed with a plurality of electronic paper display devices in an easy manner 
     &lt;Modifications&gt; 
     While the invention has been described in detail with reference to the embodiments thereof, it would be apparent to those skilled in the art that various changes and modifications may be made therein without departing from the spirit of the invention. 
     For example, the image processing device is not limited to an MFP, but may be a printing device, a copier device, or the like, as long as the device has an image processing function. Also, the image processing device may instead be an information processing device, such as a personal computer or a workstation. 
     The electronic paper display device may be provided with a motion sensor or the like, such that the orientation of the electronic paper display device is determined based on a detection signal from the motion sensor. In this case, the display process is executed each time the orientation of the electronic paper display device is changed, so that the electronic paper display device displays image data appropriate for the orientation of the electronic paper display device. For example, when the electronic paper display devices  20 A and  20 B displaying the two-page spread as shown in  FIG. 5  are rotated upside down by 180 degrees while the connection therebetween is maintained, then the image data displayed thereon may be switched between the electronic paper display devices  20 A and  20 B and the orientation of displayed images may be inverted, in accordance with the rotation. 
     In the above-described embodiments, a plurality of electronic paper display devices are physically connected. However, the connection is not limited to such physical connection. A complete image can be displayed using a plurality of electronic paper display devices, as long as the relative positiond therebetween can be determined. For example, the position may be determined using such wireless communication system as GPS. 
     In the above-described embodiments, the electronic paper display device determines a position thereof with the connectors  69 A,  69 B,  69 C, and  69 D. However, this is not limitation of the invention. For example, a user may manually input position information for each electronic paper display device to enable the electronic paper display device or the MFP  100  to determine the position based on the inputted position information. 
     In the above-described embodiments, the MFP  100  wirelessly communicates with the electronic paper display devices  20 A and  20 B. However, the communication therebetween may be wired communication.