Patent Publication Number: US-2012026189-A1

Title: Display device, display system and display method

Description:
The entire disclosure of Japanese Patent Application No. 2010-170619, filed Jul. 29, 2010 is expressly incorporated by reference herein. 
     BACKGROUND 
     1. Technical Field 
     The present invention relates to a display device, a display system, and a display method. 
     2. Related Art 
     For example, in JP-A-2004-54783, a display system is disclosed in which captured image data of which size is converted is received from a plurality of terminal devices, is composed as image data of one screen, and is displayed. In addition, in JP-A-2004-54783, it is described that an image displayed on a specific terminal device is enlarged, removed, or added by a user operating a remote controller of a display device. 
     However, for example, in a conference or the like, in a case where a presenter performs enlargement or the like of an image displayed on a terminal device used by a participant by using a remote controller in accordance with a request from the participant, the presenter needs to specify the image, understand the content of the request, and perform a remote controller operation in accordance with the request. Accordingly, it takes time to perform the operation. In addition, in JP-A-2004-54783, although it is described that a divided screen or the like to be displayed in an enlarged scale can be designated from the terminal device side, a specific technique is not described. Furthermore, the display device needs to appropriately display the entire image in a speedy manner even in a case where a participation request, a request for changing the image composition, and the like are received from a plurality of terminal devices. 
     SUMMARY 
     An advantage of some aspects of the invention is that it provides a display device, a display system, and a display method capable of appropriately displaying the entire image in a speedy manner even in a case where a participation request and the like are received from a plurality of terminal devices. 
     A display device according to one aspect of the invention includes: a display-side communication unit that receives participation request information and image information from a plurality of terminal devices; a display-side image generating unit that generates an entire image including individual images that are based on the image information; and a display-side display unit that displays the entire image. The display-side display unit displays an individual image that is based on the image information transmitted from the terminal device that has transmitted the participation request information first time regardless of an explicit display instruction, and does not display the individual image that is based on the image information transmitted from the terminal device that has transmitted the participation request information second or later time in a state in which there is no explicit display instruction but displays the individual image in a case where there is an explicit display instruction. 
     A display system according to one aspect of the invention includes: the above-described display device; and the above-described terminal device. The terminal device includes: a terminal-side image generating unit that generates a configuration change image used for changing a configuration of the entire image; an input unit to which operation information is input; a terminal-side information generating unit that generates the participation request information based on the operation information; and a terminal-side communication unit that transmits the image information and the participation request information toward the display device. The configuration change image includes an individual-image arranging area that represents an arrangement of the individual images in the entire image and an icon arranging area that includes icons of the terminal devices as transmission sources of the participation request information, the operation information relating to a change in the configuration is input to the input unit in accordance with an operation for each icon, and the terminal-side image generating unit generates an image that represents the icon of the terminal device to which the terminal-side image generating unit belongs in a form different from those of the icons of other terminal devices in the icon arranging area and generates the configuration change image in which mark images corresponding to the icons represented in the operation information are arranged in the individual-image arranging area based on the operation information relating to the change in the configuration. 
     A display method according to one aspect of the invention includes: receiving participation request information from a plurality of terminal devices; receiving image information from the plurality of terminal devices; generating an entire image including individual images that are based on the image information; and displaying the entire image, by using a display device. The display device displays an individual image that is based on the image information transmitted from the terminal device that has transmitted the participation request information first time regardless of an explicit display instruction, and does not display the individual image that is based on the image information transmitted from the terminal device that has transmitted the participation request information second or later time in a state in which there is no explicit display instruction but displays the individual image in a case where there is an explicit display instruction. 
     According to some aspects of the invention, the display device or the like displays an individual image that is based on the image information transmitted from the terminal device that has transmitted the participation request information first time regardless of an explicit display instruction, and does not display the individual image that is based on the image information transmitted from the terminal device that has transmitted the participation request information second or later time in a state in which there is no explicit display instruction but displays the individual image in a case where there is an explicit display instruction. Accordingly, even in a case where participation requests and the like are received from a plurality of terminal devices, the entire image can be appropriately displayed in a speedy manner. 
     In addition, according to some aspects of the invention, the display device or the like generates the entire image based on the configuration change request information, whereby the entire image can be appropriately displayed. 
     In addition, according to some aspects of the invention, the display device or the like can appropriately display the entire image by using the image configuration data and the like. 
     In addition, according to some aspects of the invention, the display device or the like can notify the terminal devices of the configuration of the entire image and the terminal device as a transmission source of the participation request information, accordingly, the terminal device can generate the configuration change image on which the latest state is reflected. 
     In addition, according to some aspects of the invention, the terminal device or the like can generate the configuration change image on which the latest state is reflected by using the image configuration data and the like. 
     In addition, according to some aspects of the invention, the terminal device or the like transmits the configuration change request information toward the display device in accordance with the operation relating to a change in the configuration, whereby the display device can change the configuration of the entire image in accordance with the operation relating to the change in the configuration. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       The invention will be described with reference to the accompanying drawings, wherein like numbers reference like elements. 
         FIG. 1  is a diagram illustrating the display state of an entire image according to a first embodiment. 
         FIG. 2  is a functional block diagram of a projector according to the first embodiment. 
         FIG. 3  is a functional block diagram of a personal computer according to the first embodiment. 
         FIG. 4  is a flowchart illustrating the image displaying sequence of a personal computer according to the first embodiment. 
         FIG. 5  is a flowchart illustrating the image displaying sequence of a projector according to the first embodiment. 
         FIG. 6  is a sequence diagram illustrating the transmission/reception of information between the personal computer and the projector according to the first embodiment. 
         FIG. 7  is a diagram illustrating an example of a search image according to the first embodiment. 
         FIG. 8  is a diagram illustrating an example of a configuration change image according to the first embodiment. 
         FIG. 9  is a diagram illustrating an example of an image transition in each device according to the first embodiment. 
         FIG. 10  is a diagram illustrating another example of an image transition in each device according to the first embodiment. 
         FIG. 11  is a diagram illustrating yet another example of an image transition in each device according to the first embodiment. 
         FIG. 12  is a diagram illustrating an example of a configuration change image according to other embodiments. 
     
    
    
     DESCRIPTION OF EXEMPLARY EMBODIMENTS 
     Hereinafter, a personal computer (PC) according to an embodiment of the invention will be described with reference to the accompanying drawings. However, the embodiments shown below do not limit the content of the invention defined in the appended claims in any way. In addition, not all the configurations shown in the embodiments described below are determined as essential for implementing the invention defined by the appended claims. 
     First Embodiment 
       FIG. 1  is a diagram illustrating the display state of an entire image  20  according to a first embodiment. In this embodiment, one projector  100  and four PCs  200 - 1  to  200 - 4  are connected to each other through an access point  300  in a wireless manner, and the projector  100  projects the entire image  20  including a maximum of four individual images  30  to  33  onto a screen  10  based on image information supplied from each of the PCs  200 . For example, a participant participating in a conference can change the configuration of individual images  30  to  33  on the entire image  20  by operating an icon or the like of a configuration change image displayed on the PC  200  used by the participant. In addition, the projector  100  is one type of display device, the PC  200  is one type of terminal device, and the projector  100  and the PCs  200  may be arranged at the same room or different rooms. Next, the functional blocks of the projector  100  and the PC  200  having such functions will be described. 
       FIG. 2  is a functional block diagram of a projector  100  according to the first embodiment. The projector  100  is configured so as to include: a display-side communication unit  110  that communicates with the PC  200  through the access point  300 ; a display-side information generating unit  120 ; a display-side image generating unit  130 ; a display-side storage unit  140 ; a display-side update unit  150  that updates data stored in the display-side storage unit  140 ; and a projection unit  190  that is one type of display-side display unit. In addition, the display-side storage unit  140  stores image data  142  that represents image information or the like transmitted from the PC  200 , image configuration data  144  that represents the configuration of the entire image  20  and the configuration change image, device managing data  146  that represents a device as a communication target, and the like therein. Here, the display-side communication unit  110  is one type of reception unit that receives image information and the like from the PC  200 . 
       FIG. 3  is a functional block diagram of the PC  200  according to the first embodiment. The PC  200  is configured so as to include: a terminal-side communication unit  210  that communicates with the projector  100  through the access point  300 ; a terminal-side information generating unit  220 ; a terminal-side image generating unit  230 ; a terminal-side storage unit  240 ; a terminal-side update unit  250  that updates data stored in the terminal-side storage unit  240 ; and a terminal-side display unit  290 . In addition, the terminal-side storage unit  240  stores image data  242  that represents image information or the like, image configuration data  244  that represents the configuration of the configuration change image, device managing data  246  that represents a communication target device, and the like therein. Furthermore, the terminal-side communication unit  210  is one type of transmission unit that transmits image information and the like toward the projector  100 . 
     The projector  100  and the PC  200  may use the following hardware and serve as each unit described below. For example, in the projector  100  and the PC  200 , the display-side communication unit  110  and the terminal-side communication unit  210  may use wireless communication units or the like, the display-side information generating unit  120 , the display-side update unit  150 , the terminal-side information generating unit  220 , and the terminal-side update unit  250  may use CPUs or the like, the display-side image generating unit  130  and the terminal-side image generating unit  230  may use image processing circuits or the like, the display-side storage unit  140  and the terminal-side storage unit  240  may use RAMs or the like, the input unit  260  may use an universal serial bus (USB) port that is connected to a keyboard, a mouse, or the like, the projection unit  190  may use a lamp, a liquid crystal panel, a liquid crystal driving circuit, a lens, or the like, and the terminal-side display unit  290  may use a back light, a liquid crystal panel, or a liquid crystal driving circuit or the like. The computer included in the PC  200  may serve as the terminal-side image generating unit  230  or the like by reading out the program stored in the information storage medium  280 . As such information storing media  280 , for example, there are a CD-ROM, a DVD-ROM, a ROM, a RAM, an HDD, and the like. 
     Next, the projection sequence of the entire image  20  according to a configuration change request of an image by using the projector  100  and the PC  200  will be described.  FIG. 4  is a flowchart illustrating the image displaying sequence of the PC  200  according to the first embodiment.  FIG. 5  is a flowchart illustrating the image displaying sequence of the projector  100  according to the first embodiment. In addition,  FIG. 6  is a sequence diagram illustrating the transmission/reception of information between the PC  200  and the projector  100  according to the first embodiment. 
     First, the image displaying sequence of the PC  200  will be described with reference to  FIG. 4 . A participant in a conference, in order to connect his or her PC  200  to the projector  100 , operates a keyboard, a mouse, or the like of the PC  200 , thereby issuing an execution instruction of a projector search program. It is assumed that the projector search program is installed to the PC  200  in advance. The terminal-side information generating unit  220  generates state checking information used for checking the connection state of each device on a network and the like based on information representing the execution instruction input from the input unit  260 , and the terminal-side communication unit  210  transmits the state checking information toward the projector  100  and receives state notifying information that represents the connection state or the like of each device from the projector  100 . The terminal-side update unit  250  updates the device managing data  246  based on the state notifying information, the terminal-side image generating unit  230  generates a search image that represent a search result of the projector based on the image data  242  and the device managing data  246 , and the terminal-side display unit  290  displays the search image (Step S 1 ). 
       FIG. 7  is a diagram illustrating an example of a search image  400  according to the first embodiment. The search image  400  is an image that is displayed on the screen of the PC  200  by executing the above-described projector search program in the PC  200 . The search image  400  includes: a search result displaying area  410  that represents the projector state, a projector name, an IP address, and the like that are represented in the device managing data  246 ; a connected projector list displaying area  420  that represents projectors as connection destinations; an update button image  430  that is used for acquiring a recent search result; a clear button image  440  that is used for clearing the connected projector list displaying area  420 ; a registration button image  450  that is used for registering a new projector in the connected projector list displaying area  420 ; an option setting button image  460 ; and a participation button image  470  used for participating in a conference (connects the PC  200  to the projector  100 ). 
     The participant issues a participation instruction for the conference by clicking on the participation button image  470  using the mouse of the PC  200 . The terminal-side information generating unit  220  generates participation request information based on the information that represents the participation instruction transmitted from the input unit  260 , and the terminal-side communication unit  210  transmits the participation request information toward the projector  100  and receives the state notifying information from the projector  100 . The terminal-side update unit  250  updates the device managing data  246  based on the state notifying information (Step S 2 ). 
     The terminal-side update unit  250  determines whether or not the terminal-side communication unit  210  has received image configuration information representing the configuration of a configuration change image from the projector  100  (Step S 3 ). In a case where the image configuration information has been received, the terminal-side update unit  250  updates the image configuration data  244  based on the image configuration information. The terminal-side image generating unit  230  generates a configuration change image based on the image configuration data  244 , and the terminal-side display unit  290  displays the configuration change image (Step S 4 ). 
       FIG. 8  is a diagram illustrating an example of a configuration change image  500  according to the first embodiment. The configuration change image  500  includes: display mode button images  510  to  514  that are used for changing the number of individual images configuring the entire image  20 ; an individual-image arranging area  530  that is configured by four display target areas  531  to  534  forming two rows and two columns; a display button image  520  that is used for instructing the display of the entire image  20 ; an image mute button image  522  that is used for issuing an instruction for displaying a user logo image or the like instead of the entire image  20 ; a pause button image  524  that is used for issuing an instruction for maintaining the current display of the entire image  20 ; an icon arranging area  540  in which icons  550  to  556  are arranged; a rectangular cursor image  590  that is used for moving among the display target areas  531  to  534  in accordance with an operation so as to select an individual image to be displayed; and the like. In addition, the configuration change image  500  includes a menu image that represents “file”, “tools” and “help”, an image that represents a connected projector name, and the like. 
     For example, the configuration change image  500  shown in  FIG. 8  is an image that is displayed on a screen of the PC  200 - 1  (computer name is “CPA”). In the individual-image arranging area  530 , a mark image  570  that represents “CPA” is arranged in a display target area  531  located on an upper-left area, a mark image  572  that represents “CPB” (PC  200 - 2 ) is arranged in a display target area  532  located on an upper right area, and a mark image  574  that represents “CPC” (PC  200 - 3 ) is arranged in a display target area  533  located in the lower left area. In addition, in a display target area  534  located in the lower right area, a mark image is not arranged, and accordingly, a depressed image  580  in which a mark image has a depressed shape is arranged. In addition, in a case where the mark images  570  to  574  are currently displayed in the entire image  20 , the backgrounds of the mark images  570  to  574  are displayed in white. On the other hand, in a case where the mark images  570  to  574  are not currently displayed, the backgrounds of the mark images  570  to  574  are displayed in gray. For example, in the example shown in  FIG. 8 , the backgrounds of the mark images  570  and  572  are in white, and which represents that two individual images of the PC  200 - 1  and PC  200 - 2  are horizontally aligned so as to be arranged in the entire image  20 . In addition, the background of the depressed image  580  is in gray. 
     In addition, in the icon arranging area  540 , icons  552  to  556  representing other PCs  200  are arranged in the order of participation (the order of connection to the projector  100 ) from the left side in an other-device area  544  located on the right side, and an icon  550  that represents the own device is fixedly arranged in an own device area  542  located on the left side regardless of the order of the participation. The backgrounds of the icons  550  to  556  are changed in accordance with the display states of the individual-image arranging area  530 . For example, in the example shown in  FIG. 8 , icon background images  560  and  562  arranged on the backgrounds of the icons  550  and  552  that are in the current-display state, in which a mark image is displayed, and a corresponding individual image is displayed, are displayed in white (first state), and an icon background image  564  arranged on the background of the icon  554  that is in a display standby state, in which a mark image is displayed, but an individual image is not displayed, is displayed in gray (second state). In addition, on the background of an icon  556  that is in the non-display state in which any mark image is not displayed, nothing is displayed (third state). Furthermore, the icon  550  of the own terminal device is displayed to be larger than the icons  552  to  556  of other terminal devices, and the mark image  570  of the own terminal device is displayed to be larger than the mark images  572  and  574  of other terminal devices. The icons  550  to  556  are respectively displayed in different colors, and the mark images  570  to  574  are respectively displayed in different colors as well. In addition, the icons  550  to  556  and the mark images  570  to  574  are displayed with the host names (the name can be also set by a user) of the PCs  200  being added thereto. 
     According to this embodiment, when the projector  100  and the PC  200  set up a connection, the PC  200  is notified of first state notifying information including color information unique to the PC  200  that is assigned by the projector  100 . Here, the color information is information that is used for designating a color used for an icon and a mark image. The color information may be a numeric value corresponding to a color set in advance or text data that represents the name of the color. Furthermore, the color information may be an RGB value that is represented by a predetermined number of bits. The PC  200  that has newly setup a connection with the projector  100  notifies other PCs  200  and other terminal devices that have already set up connections with the projector  100  of second state notifying information including color information unique to the PC  200  that is assigned by the projector  100 . Other PCs  200  that have received the color information from the PC  200  that has newly set up the connection with the PC  100  notify other PCs  200  that have set up connections with the projector  100  of third state notifying information including color information that is assigned to each own terminal device. Accordingly, the correspondence between the color of the icon arranged in the icon arranging area  540  of the configuration change image  500  and the PC  200  that has set up a connection with the projector  100  is the same in any PC  200 . Therefore, even in a case where a plurality of PCs  200  has set up connections with the projector  100 , each participant can easily specify a desired PC  200  by using the color of the icon. In addition, in a case where the projector  100  transmits the first state notifying information including the color information of all the PCs  200 , the notification of the third state notifying information is not necessary. 
     Each participant operating each PC  200  can display and operate the search image  400  and the configuration change image  500  on the screen of each PC  200  and can change the configuration of the individual-image arranging area  530 , for example, by performing drag-and-drop of the icons  550  to  556  from the icon arranging area  540  to the individual-image arranging area  530 . For example, each participant moves a mouse pointer up to the display target area  532  located on the upper right side (icon having the same shape as the icon  552  is moved in association with the mouse pointer in the state in which the icon  552  is left in the icon arranging area  540 ) and separates the finger from the mouse in the state in which the mouse pointer is clicked with overlapping the position of the icon  552  of the PC  200 - 2  (CPB), whereby the mark image  572  corresponding to the PC  200 - 2  can be arranged in the display target area  532 . Accordingly, the entire image  20  including the individual image of the PC  200 - 2  can be projected to the projector  100 . The terminal-side information generating unit  220  determines whether there is a configuration change operation based on the information transmitted from the input unit  260  (Step S 5 ). When there is the configuration change operation, the terminal-side information generating unit  220  generates configuration change request information, and the terminal-side communication unit  210  transmits the configuration change request information toward the projector  100  (Step S 6 ). 
     In addition, the terminal-side information generating unit  220  determines whether or not the transmission start request information of image information has been received from the projector  100  by the terminal-side communication unit  210  (Step S 7 ). When the transmission start request information is received, the terminal-side information generating unit  220  generates image information representing a graph image shown in  FIG. 1  or the like based on the image data  242 , and the terminal-side communication unit  210  transmits the image information toward the projector  100  (Step S 8 ). In addition, the terminal-side image generating unit  230  generates a graph image shown in  FIG. 1  or the like, consecutively captures the graph image or the like, and stores the graph image or the like in the terminal-side storage unit  240  as the image data  242 . 
     Furthermore, the terminal-side information generating unit  220  determines whether or not transmission stop request information of the image information has been received from the projector  100  by the terminal-side communication unit  210  (Step S 9 ). When the transmission stop request information is received, the terminal-side information generating unit  220  stops generating the image information, and the terminal-side communication unit  210  stops the transmitting of the image information (Step S 10 ). In such a case, the terminal-side image generating unit  230  may stop the capturing of the image. 
     In addition, the participant can cut off the communication of his or her own PC  200  by selecting “leave” from a submenu of “tools” of the configuration change image  500 , and the participant can cut off the communication of all the PCs  200  by selecting “completion of conference” from the submenu. The terminal-side information generating unit  220  determines whether or not “completion of conference” has been selected based on information input from the input unit  260  (Step S 11 ). When “completion of conference” is selected, the terminal-side information generating unit  220  generates completion request information, and the terminal-side communication unit  210  transmits the completion request information toward the projector  100  (Step S 12 ). In addition, the terminal-side information generating unit  220  determines whether or not completion notifying information transmitted from the projector  100  in accordance with the reception of the completion request information has been received by the terminal-side communication unit  210  (Step S 13 ). In a case where the completion request information is transmitted or the completion notifying information is received, the PC  200  completes a series of processes described above and displays the search image  400 . On the other hand, in a case where the completion of the processes is not required, the PC  200  repeatedly performs the process of Steps S 3  to S 13  described above. In addition, when “completion of conference” is selected, the terminal-side information generating unit  220  may generate a confirmation image that represents a text string of “All the users participating in the conference will be cut off from the projector and are returned to a search screen. Has the conference been completed?”. In addition, in a case where the completion notification information is received, the terminal-side information generating unit  220  may generate a notification image that represents a text string of “The conference has been completed by other users. Now, the search screen will be returned”. 
     Next, the processing sequence of the projector  100  will be described with reference to  FIG. 5 . The display-side information generating unit  120  determines whether or not the state checking information has been received from the PC  200  by using the display-side communication unit  110  (Step P 1 ). When the state checking information is received, the display-side information generating unit  120  generates state notifying information based on the device managing data  146 , and the display-side communication unit  110  transmits the state notifying information toward the PC  200  as a transmission source (Step P 2 ). 
     In addition, the display-side update unit  150  determines whether or not the participation request information has been received from the PC  200  by the display-side communication unit  110  (Step P 3 ). When the participation request information has been received, the display-side update unit  150  updates the device managing data  146  based on the participation request information. In addition, in this case, the display-side information generating unit  120  generates the state notifying information based on the device managing data  146  and generates image configuration information based on the image configuration data  144  as necessary. The display-side communication unit  110  transmits the state notifying information and the image configuration information toward each participating PC  200  (Step P 4 ). 
     Furthermore, the display-side update unit  150  determines whether or not the configuration change request information has been received from the PC  200  by the display-side communication unit  110  (Step P 5 ). When the configuration change request information is received, the display-side update unit  150  updates the image configuration data  144  based on the configuration change request information. In addition, in this case, the display-side information generating unit  120  generates the image configuration information based on the image configuration data  144  and generates transmission start requesting information and transmission stop requesting information as necessary. To be more specific, for example, in a case where an individual image needs to be newly displayed, the display-side information generating unit  120  generates the transmission start requesting information for the PC  200  that is the transmission source of the image information of the individual image. On the other hand, in a case where the individual image does not need to be display, the display-side information generating unit  120  generates the transmission stop requesting information for the PC  200  that is the transmission source of the image information of the individual image. The display-side communication unit  110  transmits the image configuration information, the transmission start requesting information, and the transmission stop requesting information toward each participating PC  200 . In addition, the display-side image generating unit  130  generates an entire image  20  in accordance with the image configuration based on the image data  142  and the image configuration data  144 , and the projection unit  190  projects the entire image  20  (Step P 6 ). 
     In addition, the display-side update unit  150  determines whether or not the image information has been received from the PC  200  by the display-side communication unit  110  (Step P 7 ). When the image information is received, the display-side update unit  150  updates the image data  142  based on the image information. In addition, in this case, the display-side image generating unit  130  generates the entire image  20  based on the image data  142  and the image configuration data  144 , and the projection unit  190  projects the entire image  20  (Step P 8 ). 
     The display-side information generating unit  120  determines whether or not completion requesting information has been received from the PC  200  by the display-side communication unit  110  (Step P 9 ). When the completion requesting information is received, the display-side information generating unit  120  generates completion notifying information. The display-side communication unit  110  transmits the completion notifying information toward each PC  200 . The display-side update unit  150  updates the device managing data  146  and the image configuration data  144 , for example, to be the initial states or the like in accordance with the completion of the conference (Step P 10 ). The projector  100  determines whether or not there is a projection completion instruction (Step P 11 ). When there is the projection completion instruction, the projector  100  completes a series of processes described above. 
     Here, an image transition in the projector  100  and the PCs  200 - 1  to  200 - 4  will be described in more detail.  FIG. 9  is a diagram illustrating an example of an image transition in each device according to the first embodiment.  FIG. 10  is a diagram illustrating another example of an image transition in each device according to the first embodiment.  FIG. 11  is a diagram illustrating yet another example of an image transition in each device according to the first embodiment. Here, for simplification of the description, it is assumed that the PC  200 - 1  (CPA) displays an image A, the PC  200 - 2  (CPB) displays an image B, the PC  200 - 3  (CPC) displays an image C, and the PC  200 - 4  (CPD) displays an image D. In addition, time points t 1  to t 12  are assumed as continuous time points. 
     At the time point t 1 , there is no PC  200  participating in a conference, and the projector  100  (EMP00000000) projects a single-color image. At the time point t 2 , in a case where CPA participates in the conference first time, the projector  100  projects an entire image  20  including the image A of CPA in accordance with the participation. On the other hand, at the time point t 3 , in a case where CPB participates in the conference, the projector  100  does not automatically project the image B and continues to project the entire image  20  including the image A of CPA. Furthermore, at the time point t 4 , in a case where CPC and CPD participates in the conference, the projector  100  does not automatically projects the image C and the image D and continues to project the entire image  20  including the image A of CPA. In other words, while automatically projecting the image of the PC  200  participating in the conference first time regardless whether there is an explicit display instruction, the projector  100  does not project the image of the PC  200  that participates in the conference second or later time without an explicit display instruction. 
     At the time point t 5 , in a case where the participant operating CPA performs drag-and-drop of the icon of CPB in an upper right area of the individual-image arranging area  530  in the configuration change image  500  displayed on the PC  200 - 1 , the display mode is maintained to be a one-screen display mode, and accordingly, the entire image  20  projected by the projector  100  is not changed. In addition, even in a case where drag-and-drop of the icon is performed from the icon arranging area  540  to the individual-image arranging area  530 , the icon remains in the icon arranging area  540 , and a mark image corresponding to the icon is added to the individual-image arranging area  530 . At the time point t 6 , in a case where the participant operating CPA clicks on a two-screen display mode button image  512  on the configuration change image  500  displayed in the PC  200 - 1 , the projector  100  projects an entire image  20  including images A and B corresponding to the mark images located in the row in which the cursor image  590  is present. In addition, in this case, the background of the display target area  532  located on the upper right side in the individual-image arranging area  530  of the PCs  200  is changed from gray to white. 
     At the time point t 7 , in a case where the participant operating CPA, in the configuration change image  500  displayed in the PC  200 - 1 , performs drag-and-drop for the icon of CPC to the lower left area of the individual-image arranging area  530  and performs drag-and-drop for the icon of CPD to the lower right area of the individual-image arranging area  530 , depressed images are changed to mark images in the display target areas  533  and  534  of each PC  200 , but the entire image  20  projected by the projector  100  is not changed. 
     At the time point t 8 , in a case where the participant operating CPA clicks on a four-screen display mode button image  514  on the configuration change image  500  displayed in the PC  200 - 1 , the projector  100  projects an entire image  20  including images A, B, C, and D corresponding to the mark images placed in the individual-image arranging area  530 . In addition, in this case, the background of the display target area  533  located on the lower left side of the individual-image arranging area  530  of each PC  200  and the background of the display target area  534  located on the lower right side of the individual-image arranging area  530  are changed in color from gray to white, and the icon background images of the icons of CPC and CPD are changed in color from gray to white. 
     At the time point t 9 , in a case where the participant operating CPA moves the cursor image  590  to the display target area  533  located on the lower left side and clicks on the two-screen display mode button image  512  in the configuration change image  500  displayed in the PC  200 - 1 , the projector  100  projects an entire image  20  including images C and D corresponding to the mark images placed in the individual-image arranging area  530 . In addition, in this case, the background of the display target area  531  located on the upper left side and the background of the display target area  532  located on the upper right side in the individual-image arranging area  530  of each PC  200  are changed in color from white to gray, and the icon background images of the icons of CPA and CPB are changed in color from white to gray. Since the cursor image  590  operates independently in each PC  200 , as illustrated in  FIG. 11 , even when the PC  200 - 1  moves the cursor image  590 , the cursor image  590  is not moved in other PCs  200 - 2  to  200 - 4 . 
     At the time point t 10 , in a case where the participant operating CPA performs drag-and-drop of the mark images of CPB and CPC to the icon arranging area  540  in the configuration change image  500  displayed in the PC  200 - 1 , the projector  100  changes the color of a portion in which the image C is located to white and projects an entire image  20  including the image D. In addition, in this case, the mark images disappear from the display target area  532  located on the upper right side and the display target area  533  located on the lower left side in the individual-image arranging area  530  of each PC  200 , and the icon background images of the icons of CPB and CPC disappear as well. In addition, the mark image disappears from the original place in accordance with the movement or the drag-and-drop, and a depressed image  580  is displayed in the display target area in which the mark image disappears. 
     At the time point t 11 , in a case where the participant operating CPA performs drag-and-drop of the mark image of CPA located on the upper left side to the display target area  533  located on the lower left side in the configuration change image  500  displayed in the PC  200 - 1 , the projector  100  projects an entire image  20  including the images A and D. In addition, in this case, the icon background image of the icon of the CPA is changed in color from gray to white in the icon arranging area  540  of each PC  200 . 
     At the time point t 12 , in a case where the participant operating CPA performs double clicks on the icon of CPB in the state in which the mouse cursor overlaps the icon of CPB in the configuration change image  500  displayed in the PC  200 - 1 , the mark image of CPB is displayed in the display target area  531  located on the upper left side that has a highest priority level out of vacant areas in which a mark image is not arranged among the display target areas  531  to  534 , and a gray icon background image is added to the icon of CPB. In addition, in a case where an icon within the icon arranging area  540  that can be selected is double-clicked in the state in which there is no vacant area in the individual-image arranging area  530 , a mark image having the lowest priority level that is present in the display target area  534  located on the lower right side disappears, and a mark image corresponding to the double-clicked icon is displayed in the display target area  534 . In addition, not only first operation information according to a general drag-and-drop operation but also second operation information according to the double click operation are input to the input unit  260 , and accordingly, the terminal-side image generating unit  230  can generate the configuration change image  500  based on not only the first operation information but also the second operation information. In addition, the second operation information can be input by using a keyboard connected to the PC  200 - 1  as well. For example, it may be configured such that, by selecting an icon within the icon arranging area  540  through a TAB key of the keyboard that is input by the participant, the corresponding icon is displayed with being highlighted, and the mark image corresponding to the icon selected through the input of the Enter key of the keyboard is displayed in the individual-image arranging area  530 . In this case, it is not necessary that the mouse cursor overlaps a desired icon. In such a case, since an icon can be selected through a simple keyboard operation, a user who is not acquainted with the operation of a pointing device can easily change the configuration of the entire image. 
     As above, according to this embodiment, since the PC  200  generates an image representing the icon  550  of the own terminal device in a form different from those of the icons  552  to  556  of other terminal devices in the icon arranging area  540 , a user can easily operate the icon  550  of the own terminal device of which the frequency of the operation is higher than those of the icons  552  to  556  of other terminal devices. Accordingly, in a case where an entire image  20  including individual images that are based on the image information transmitted from the PC  200  is displayed by the projector  100 , the operation for changing the configuration of the entire image  20  can be easily performed. Therefore, even in a case where the configuration of the entire image  20  is changed by using the PC  200  of each participant, the participant can efficiently perform a desired operation. 
     In addition, according to this embodiment, the PC  200  displays the icon  550  and the mark image  570  of the own terminal device to be larger than the icons  552  to  556  and the mark images  572  and  574  of other terminal devices, whereby the user can easily operate the icon or the like of the own terminal device of which the frequency of the operation is higher than those of the icons or the like of other terminal devices. Furthermore, according to this embodiment, the PC  200  displays a depressed image  580  in a depressed state in the display target area  534  in which the mark images  570  to  574  are not arranged, whereby the user can perform a drag-and-drop operation more easily than a case where an image in a flat state is displayed in the display target area  534  and can easily acquire the movement destinations of the icons  550  to  556 . In addition, according to this embodiment, the PC  200  fixes the display position of the icon  550  of the own terminal device, whereby the user can operate the icon of the own terminal device of which the frequency of the operation is higher than those of the icons  552  to  556  of the other terminal device. 
     Furthermore, according to this embodiment, the PC  200  generates the configuration change image  500  that includes the individual-image arranging area  530  that represents the arrangement of the individual images  30  to  33  in the entire image  20  displayed by the projector  100 , whereby the configuration of the entire image  20  can be presented in an easy manner. In addition, according to this embodiment, by displaying the icon arranging area  540  by using the PC  200  in which an identification name (a host name or the like) is displayed together with an icon imitating the participant so as to be included in the configuration change image  500 , and accordingly, each participant can check the current participants, so that the participants can be easily checked even in a conference between remote places or the like. Furthermore, according to this embodiment, the PC  200  changes the display state of the individual-image arranging area  530  in accordance with an operation, and accordingly, even in a case where the configuration of the entire image  20  is changed, such a change can be reflected on the display of the individual-image arranging area  530  at a speedy manner. In addition, according to this embodiment, the PC  200  changes the icon background images present on the backgrounds of the icons as operation targets in accordance with the display state of the individual-image arranging area  530 , whereby the user can visually check the display state in an easy manner and can perform an operation in a speedy manner. 
     In addition, according to this embodiment, the PC  200  changes the icon background images in accordance with the assignment states of mark images or the like, whereby the user can easily perform an operation at the time of performing an operation relating to the icons in accordance with the display state. Furthermore, according to this embodiment, the PC  200  changes the icon background image to three different states in accordance with three display states, whereby the user easily perform an operation relating to the icon in accordance with the display state. In addition, according to this embodiment, the PC  200  determines whether or not an individual image is displayed based on the operation information that represents the position of the cursor image  590  and the operation information that represents the press-down operation of the display button images  520  to  524 , whereby the user can change the display of the individual image through various operations and can change the configuration of the entire image  20  in a speedy manner. 
     Furthermore, according to this embodiment, the PC  200  also responds to a double-click operation other than the drag-and-drop operation, whereby the operation for changing the configuration of the entire image  20  can be easily performed in a case where the entire image  20  including the individual images  30  to  33  on the basis of the image information transmitted from the PC  200  is displayed by the projector  100 . For example, since an operation in a mobile information terminal or the like is performed using a touch panel or the like, it may be difficult and take time to perform the drag-and-drop operation. However, according to this embodiment, the user can change the configuration of the entire image  20  through a double-click operation (continuous touch operations), and accordingly, the user can comfortably perform a desired operation even in a case where a mobile information terminal or the like is used. In addition, according to this embodiment, the PC  200  can arrange the mark image in accordance with a double-click operation in the state in which the mouse pointer overlaps the icon, and accordingly, a mark image can be automatically arranged in a vacant area. 
     In addition, according to this embodiment, the projector  100  displays an individual image based on the image information transmitted from the PC  200  that has transmitted the participation request information first time regardless of an explicit display instruction, does not display an individual image on the basis of the image information transmitted from the PC  200  that has transmitted the participation request information second or later time in the state in which there is no explicit display instruction but displays the individual image in a case where there is an explicit display instruction. Accordingly, even in a case where participation requests or the like is received from a plurality of the PCs  200 , the entire image can be appropriately displayed in a speedy manner. In addition, in a case where the display device displays an individual image on the basis of the image information transmitted from the PC  200  that has transmitted the participation request information second or later time, the existing previous configuration of the entire image is changed so as to interfere with a presentation or the like. However, according to this embodiment, the projector  100  can accept a participation request or the like from the PC  200  for the second or later time without changing the existing configuration of the entire image. On the other hand, for example, in a case where the display device does not display individual images that are based on the image information transmitted from all the PCs  200  that have transmitted the participation request information, the PC  200  that has issued the first participation request needs to issue an explicit display instruction all the time, thereby degrading the convenience. However, according to this embodiment, the projector  100  can instantly display an individual image that is based on the image information transmitted from the PC  200  that has transmitted the participation request information first time, thereby improving the convenience. 
     Furthermore, according to this embodiment, the projector  100  generates the entire image  20  based on the configuration change request information transmitted from the PC  200 , whereby the entire image  20  can be appropriately displayed. In addition, according to this embodiment, the projector  100  uses the image configuration data  144  and the like, whereby the entire image  20  can be appropriately displayed. Furthermore, according to this embodiment, the projector  100  can notify each PC  200  of the configuration of the entire image  20  and the participating PCs  200 , whereby the PC  200  can generate the configuration change image  500  on which the latest state is reflected. 
     In addition, according to this embodiment, the PC  200  uses the image configuration data  244  and the like, whereby the configuration change image  500  on which the latest state is reflected can be generated. Furthermore, according to this embodiment, the PC  200  transmits the configuration change request information in accordance with an operation relating to the change in the configuration toward the projector  100 , whereby the projector  100  can change the configuration of the entire image  20  in accordance with the operation relating to the change in the configuration. 
     Other Embodiments 
     The application of an embodiment of the invention is not limited to the above-described embodiment, and any modification can be made therein. For example, the number of the PCs  200  is not limited to four but may be three or less or five or more. In addition, the number of the projectors  100  may be two or more.  FIG. 12  is a diagram illustrating an example of a configuration change image  501  according to other embodiments. For example, the configuration change image  501  may be generated such that, in a case where the number of the PCs  200  participating in a conference is six or more, and the icons of only up to five CPEs can be displayed in the other-device area  544 , the terminal-side image generating unit  230  adds a scrollbar image  592  in the other-device area  544 , and the icons of the sixth PC  200  and the PC  200  after that are displayed in the other-device area  544  through scroll of the scrollbar image  592 . 
     In addition, in the above-described embodiment, although the terminal-side image generating unit  230  changes the form of the icon background image in accordance with the display state of the individual-image arranging area  530 , the form of the icon may be changed. Furthermore, the change in the form is not limited to a change in the color and may include, for example, a change in the pattern, a change in the shape, and a change in the emphasis effect through blinking or the like. 
     In addition, the operation other than the drag-and-drop operation, which corresponds to the second operation information, is not limited to the double-click operation and, for example, may be an operation through selection of an item from a menu displayed by clicking the right button of the mouse, an operation of a key of the keyboard, a contact operation for a touch panel of a mobile information terminal or the like, or the like. For example, the terminal-side update unit  250  or the terminal-side information generating unit  220  may determine a display target area in the individual-image arranging area  530  that is instructed by the user in accordance with a change in the contact position (for example, the movement direction, the movement direction and the movement speed, the movement direction and the movement amount, or the like) on a touch panel or the like, based on the information transmitted from the input unit  260 . For example, the terminal-side update unit  250  may determine that a display target area  531  located on the upper left side is instructed in a case where the user moves the icon  550  to the left side at a speed equal to or higher than a reference value (or a movement amount equal to or higher than a reference value) in the state shown in  FIG. 8 . On the other hand, in a case where the user moves the icon  550  to the left side at a speed lower than a reference value (or a movement amount less than a reference value), the terminal-side update unit  250  may determine that the user instructs the display target area  533  located on the lower left side. In addition, the technique for determining the display target area in accordance with the second operation information is not limited to the above-described technique utilizing the priority level described above and, for example, may be a technique for a random determination, a technique for determining a display target area that is closest to the double-clicked icon, a technique for determining a display target area located at the position of the cursor image  590 , a technique for determining the display target area in accordance with the change in the contact position described above, or the like. 
     In addition, the search image  400  and the configuration change image  500  may be images (for example, OSD images or the like) generated in a layer other than the layer of a graph image that is the source of the image information and the like or may be images that are captured together with the graph image and the like. Even in a case where the configuration change image  500  and the like are captured together with the graph image and the like through the specification of the OS or the like, the user can configure the display of the configuration change image  500  and the like in the entire image  20  to be visually undistinguished by displaying the configuration change image  500  and the like in a minimized form or displaying the configuration change image  500  and the like to be stepped aside to the right end in a form protruding from the screen of the PC  200 . Particularly, in the configuration change image  500 , button images for the operation are concentrated to the left side, and accordingly, even in a case where the configuration change image  500  is moved to the right side so as to protrude from the screen, the button images for the operation can be operated by the user. 
     In addition, as described above, each user can operate the icons or the like of other PCs  200  in the configuration change image  500  or  501  by using his or her own PC  200 , and thus the users may simultaneously perform different operations. For example, in a case where conflicting operations are performed, the projector  100  can give priority to an operation that is accepted first or an operation that has been lately accepted by using a reception number or the like. 
     In addition, it may be configured such that the terminal-side communication unit  210  transmits not only the image information but also audio information representing a remark or the like of a participant toward the projector  100 , and an audio output unit included in the projector  100  outputs audio that is based on the audio information. 
     In addition, the connection form between the projector  100  and the PC  200  is not limited to the wireless connection shown in  FIG. 1  and, for example, may be a wired connection through a LAN or the like. Furthermore, the display device is not limited to the projector  100  and, for example, maybe a television set, a liquid crystal monitor, an electronic device (for example, a digital camera, a cellular phone, or the like) provided with a projection function, or the like. In addition, the terminal device is not limited to the PC  200  and, for example, maybe a cellular phone, a mobile information terminal, or the like. 
     Furthermore, the computer included in the projector  100  may serve as the display-side image generating unit  130  that reads out a program stored on an information storage medium or the like. As such an information storage medium, for example, a CD-ROM, a DVD-ROM, a ROM, a RAM, an HDD, or the like can be used. 
     In addition, the projector  100  is not limited to the liquid crystal projector (a projection type or a reflection type such as an LCOS) and, for example, may be a projector that uses a digital micro-mirror device or the like. In addition, the projection unit  190  may employ a self luminescence device including a solid-state light source such as an organic EL device, a silicon light emitting device, a laser diode, or an LED, instead of a lamp. Furthermore, the function of the projector  100  may be divided into a plurality of devices (for example, a PC and a projector or the like).