Method of controlling communication with display device and display system

Abstract

To prevent hindrance when a display device displays an image based on image data transmitted from a device that has established communication with the display device, even when authorization of communication with the display device is requested from a device that has not established communication with the display device.SOLUTION: A display system comprises a plurality of devices and a display device capable of communicating with the plurality of devices. The display device can display an image in a display region, and first communication between a first device of the plurality of devices and the display device is established. When a second device requests authorization of second communication between the second device of the plurality of devices and the display device while the image is displayed in the display region, the display device transmits, to the first device, information indicating that the authorization of the second communication is requested, the first device outputs, to the first device, information for causing a user of the first device to determine whether to approve the authorization of the second communication, and the display device establishes the second communication when information indicating that the authorization of the second communication was approved is received from the first device.SELECTED DRAWING: Figure 4

Description

[Technical Field]

[0001] The present disclosure relates to a communication control method for a display device and a display system. [Background technology]

[0002] Conventionally, in order for a device such as a computer to display an image on a display device such as a projector, communication between the device such as a computer and the display device has been established. For example, Patent Document 1 discloses that a projector displays an image including an identification code on a projection surface in response to a predetermined operation such as powering on, and a user of the projector inputs the identification code displayed on the projection surface into an information terminal, thereby causing the projector to establish a connection with the information terminal. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Publication No. 2018-152663 Summary of the Invention [Problem to be solved by the invention]

[0004] However, when multiple devices can be connected to one display device, the following problem occurs. Specifically, a situation can occur in which a device that has not yet established a connection with the display device requests communication with the display device while the display device is displaying an image based on image data transmitted from a device that has already established a connection with the display device. In this situation, if the display device performs a predetermined operation and displays an image including an identification code, the display of the image based on the image data transmitted from the device with which the connection has been established is prevented. [Means for solving the problem]

[0005] A communication control method for a display device according to one embodiment of the present disclosure is a communication control method for the display device in a display system having a plurality of devices and a display device capable of communicating with the plurality of devices, wherein the display device capable of displaying an image in a display area establishes a first communication with a first device among the plurality of devices, and when the display device receives a request for authorization for a second communication between the second device and the display device from a second device among the plurality of devices while displaying an image in the display area, the display device transmits information to the first device indicating that authorization for the second communication has been requested, and the first device outputs information to the first device to allow a user of the first device to decide whether to approve the authorization for the second communication, and when the display device receives information from the first device indicating that the authorization for the second communication has been approved, the display device establishes the second communication.

[0006] A display system according to one embodiment of the present disclosure is a display system having a plurality of devices and a display device capable of communicating with the plurality of devices, wherein the display device is capable of displaying an image in a display area, and a first communication is established between a first device of the plurality of devices and the display device, and when a second device of the plurality of devices requests authorization for a second communication between the second device and the display device while the display device is displaying an image in the display area, the display device transmits information to the first device indicating that authorization for the second communication has been requested, and the first device outputs information to the first device to allow a user of the first device to decide whether to approve the authorization for the second communication, and when the display device receives information from the first device indicating that authorization for the second communication has been approved, the display device establishes the second communication. [Brief explanation of the drawings]

[0007] [Figure 1] FIG. 1 is a diagram illustrating a display system 1 according to a first embodiment. [Figure 2] FIG. 2 is a diagram showing an example of the configuration of a PC 10. [Figure 3] FIG. 2 is a diagram showing an example of the configuration of a projector 20. [Figure 4] FIG. 3 is a sequence diagram for explaining an example of the operation of the display system 1. [Figure 5] FIG. 4 is a flowchart showing an example of the operation of the projector 20. [Figure 6] FIG. 10 is a flowchart showing an example of processing when a communication request is received. [Figure 7] FIG. 10 is a diagram showing an example of a communication determination image CW. [Figure 8] FIG. 10 is a flowchart showing an example of the operation of the projector 20 in the first modified example. [Figure 9] FIG. 10 is a flowchart showing an example of a process performed when a communication request is received in the first modified example. [Figure 10] FIG. 10 is a flowchart showing an example of the operation of the projector 20 in the second modified example. [Figure 11] FIG. 10 is a flowchart showing an example of processing when image data is received. [Figure 12] FIG. 11 is a flowchart showing an example of the operation of the projector 20 in a third modified example. [Figure 13] FIG. 11 is a flowchart showing an example of the operation of a process when image data is received in a third modified example. [Figure 14] FIG. 10 is a diagram for explaining a state immediately before being changed to a hold mode. [Figure 15] FIG. 10 is a diagram for explaining a state after being changed to a hold mode. [Figure 16] FIG. 10 is a flowchart showing an example of an authorization request information transmission process. [Figure 17] FIG. 13 is a flowchart showing an example of an authorization request information transmission process in the fourth modified example. DETAILED DESCRIPTION OF THE INVENTION

[0008] Hereinafter, embodiments for carrying out the present disclosure will be described with reference to the drawings. However, in each drawing, the dimensions and scale of each part are appropriately different from those of the actual parts. Furthermore, since the embodiments described below are preferred specific examples of the present disclosure, various technically preferable limitations are applied, but the scope of the present disclosure is not limited to these embodiments unless otherwise specified in the following description to the effect that the present disclosure is limited.

[0009] 1. First embodiment 1-1. Overview of the first embodiment FIG. 1 is a diagram illustrating a display system 1 according to a first embodiment. The display system 1 is a system in which an image GC is projected onto a projection area PR of a projection surface SC that can be seen by one or more audience members W at a venue MP, and one of two or more N presenters U gives a presentation on the image GC. The venue MP is a location where an event is held where audience members W gather, and may be either indoors or outdoors. The audience members W may be specific or unspecified people. However, the audience members W do not have to be present, and a presenter U other than the presenter U currently giving a presentation among the N presenters U may be a temporary audience member. The event may be, for example, a conference, a lecture, or a class. In this embodiment, it is assumed that the N presenters U will give presentations in sequence.

[0010] As shown in FIG. 1, the display system 1 includes N PCs 10 and a projector 20. PC is an abbreviation for personal computer. The ith PC 10_i among the N PCs 10 is operated by the ith presenter U_i among the N presenters, where i is an integer from 1 to N. In this embodiment, for simplicity, the presenter U_i who operates the PC 10_i will be described in terms of the image GC projected in the projection area PR. However, the person who operates the PC 10_i and the person who describes the image GC may be different persons. The N PCs 10 are an example of "multiple devices." The presenter U is an example of a "user." Projecting an image is an example of "displaying an image." The projector 20 is an example of a "display device." The projection area PR is an example of a "display area." The multiple devices included in the display system 1 are not limited to PCs, but may also be mobile terminals and smartphones.

[0011] In the following description, when elements of the same type are to be distinguished, reference symbols such as PC10_1 and PC10_2 are used, whereas when elements of the same type are not to be distinguished, only the common number among the reference symbols is used, such as PC10.

[0012] The projector 20 can communicate with N PCs 10. In this embodiment, the projector 20 and the N PCs 10 can communicate with each other via wireless communication. Examples of wireless communication include WiFi, Bluetooth, and ZigBee. WiFi and Bluetooth are registered trademarks. However, the projector 20 and each of the N PCs 10 may be able to communicate with each other via a relay device such as a wireless router, or may be able to communicate with each other via a network such as a LAN, a WAN, or the Internet. LAN is an abbreviation for Local Area Network.

[0013] The configurations of the PC 10 and the projector 20 will be described with reference to FIGS.

[0014] 2 is a diagram showing an example of the configuration of PC 10. PC 10 has at least one processing circuit 11, a memory circuit 12, a communication circuit 14, an input unit 16, and a display unit 17. Processing circuit 11, memory circuit 12, communication circuit 14, input unit 16, and display unit 17 are interconnected by a bus 19 for communicating information.

[0015] The processing circuit 11 is a computer such as a CPU, etc. The processing circuit 11 may be configured by one or more processors.

[0016] The memory circuit 12 is configured with a magnetic storage device, a flash ROM, or the like. The memory circuit 12 is a recording medium readable by the processing circuit 11, and stores a plurality of programs including the projector communication control program PRJ and the control program PR1 executed by the processing circuit 11, as well as various information used by the processing circuit 11. The projector communication control program PRJ is an application program that controls the operation of the PC 10 in the display system 1. For example, the PC 10 downloads the projector communication control program PRJ from a server managed by the developer of the projector 20. The control program PR1 is a system program that includes the PC 10's OS, etc.

[0017] The communication circuitry 14 is hardware having a communication circuit for wirelessly communicating with other devices such as the projector 20. The communication circuitry 14 is also referred to as, for example, a network device, a network controller, a network card, or a communication module.

[0018] The input unit 16 is a device for the presenter U to input information. The input unit 16 is, for example, a mouse and a keyboard.

[0019] The display unit 17 is a device that displays an image based on the image data transmitted by the processing circuit 11. For example, the display unit 17 is an LCD or an organic EL display. LCD is an abbreviation for Liquid Crystal Display. EL is an abbreviation for Electro Luminescence. The input unit 16 and the display unit 17 may be integrated into one unit. The input unit 16 and the display unit 17 may be integrated into one unit, for example, a touch panel.

[0020] In the following description, each element of the PC 10_i may be described with the reference symbol "_i." For example, the display unit 17 of the PC 10_i may be referred to as the display unit 17_i. Furthermore, an image displayed on the display unit 17_i may be referred to as the image GP_i.

[0021] 3 is a diagram showing an example of the configuration of the projector 20. The projector 20 has at least one processing circuit 21, a memory circuit 22, a communication circuit 24, an input device 26, and a projection device 27. The processing circuit 21, the memory circuit 22, the communication circuit 24, the input device 26, and the projection device 27 are connected to one another by a bus 29 for communicating information.

[0022] The processing circuit 21 is a computer such as a CPU, etc. The processing circuit 21 may be configured by one or more processors.

[0023] The memory circuit 22 is configured with a magnetic storage device, a flash ROM, or the like. The memory circuit 22 is a recording medium readable by the processing circuit 21, and stores a plurality of programs including the control program PR2 and the communication control program PRM, as well as various information used by the processing circuit 21. The control program PR2 is a system program including the OS of the projector 20. The communication control program PRM is a program that controls the operation of the projector 20 in the display system 1.

[0024] The communication circuit 24 is hardware having a communication circuit for wirelessly communicating with other devices such as the PC 10. The communication circuit 24 is also referred to as, for example, a network device, a network controller, a network card, or a communication module.

[0025] The input device 26 is a device for the presenter U to input information. The input device 26 is, for example, a plurality of buttons including a function list display key, an up key, a down key, a left key, a right key, a confirm key, and a cancel key. Alternatively, the input device 26 may be composed of one or more types of devices such as a pointing device, a touch panel, etc. Alternatively, the projector 20 may communicate with a remote controller having the above-mentioned plurality of buttons instead of the input device 26.

[0026] The projection device 27 is a device that projects an image GC onto a projection area PR based on image data transmitted from the processing circuit 21. The projection device 27 has a light source 27a, a display panel 27b, and an optical system 27c.

[0027] The light source 27a includes a light source such as a halogen lamp, a xenon lamp, an ultra-high pressure mercury lamp, an LED, or a laser light source, and emits red, green, and blue light, respectively. LED is an abbreviation for Light Emitting Diode. The display panel 27b is an optical modulator including three light modulation elements corresponding to red, green, and blue. Each light modulation element includes, for example, a transmissive liquid crystal panel, a reflective liquid crystal panel, or a digital mirror device, and generates image light of each color by modulating light of the corresponding color. The image light of each color generated by the display panel 27b is combined by a color combining optical system to become full-color image light. The optical system 27c is a projection optical system including a projection lens and the like that focuses and projects the full-color image light from the display panel 27b onto the projection area PR as an image GC.

[0028] Returning to the explanation in Fig. 1, in the example of Fig. 1, the projector 20 is in communication with the PC 10_1, and the image GP_1 displayed on the display unit 17_1 and the image GC projected in the projection area PR are the same.

[0029] In this specification, when the image GP and the image GC are the same, it means that the image data transmitted by the processing circuit 11 to the display unit 17 is the same as the image data transmitted by the processing circuit 21 to the projection device 27. Therefore, even if the color reproduction degree of the display unit 17 is different from the color reproduction degree of the projection device 27, as long as the image data transmitted by the processing circuit 11 to the display unit 17 is the same as the image data transmitted by the processing circuit 21 to the projection device 27, the image GP and the image GC are considered to be the same.

[0030] 1-2. Regarding the progress of the event During the event, while the first presenter U_1 is explaining about the image GC, presenter U_2, who is to make a presentation after presenter U_1, requests to prepare for projection on the projector 20. An example of preparing for projection is establishing a connection between PC10_2 and the projector 20. Establishing a connection means setting up a logical communication path before starting data transfer. More specifically, establishing a connection means PC10 logging in to the service that allows the projector 20 to project an image. Alternatively, establishing a connection may involve performing a three-way handshake if TCP is used for communication between PC10 and projector 20. TCP stands for Transmission Control Protocol. Once the connection is established, PC10 can access the projector 20, and presenter U can prepare for projection. In the following description, establishing a connection between PC10 and projector 20 may be referred to as "PC10 logging in to projector 20."

[0031] Generally, the time available for presenter U to give his / her presentation is allocated in advance. If a problem occurs in which PC 10_2 cannot log in to the projector 20, and it takes time to resolve this problem, the time available for presenter U_2 to give his / her presentation may be shortened. Therefore, by having PC 10_2 log in to the projector 20 while presenter U_1 is giving his / her presentation regarding the image GC, presenter U_2 can smoothly continue his / her presentation after presenter U_1 has finished his / her presentation.

[0032] The method by which the PC 10 logs in to the projector 20 is that the projector 20 displays an image including an identification code in the projection area PR in response to a predetermined operation such as turning on the power. The presenter U inputs the identification code displayed in the projection area PR into the PC 10, which causes the PC 10 to log in to the projector 20.

[0033] A situation may arise in which PC10_2 requests permission to connect to the projector 20 while presenter U_1 is explaining about the image GP in order to log in to the projector 20. In this situation, if the projector 20 displays an image including an identification code in the projection area PR, the display of the image GP based on the image data transmitted from PC10_1 may be obstructed. If the display of the image GP based on the image data transmitted from PC10_1 is obstructed, presenter U_1 may not be able to continue with his explanation about the image GP. Furthermore, presenter U_1 must explain to audience W that the image including the identification code is unrelated to the content of presenter U_1's explanation.

[0034] Therefore, in the display system 1 of this embodiment, when PC 10_2 requests authorization for communication between PC 10_2 and the projector 20, authorization request information indicating that authorization for this communication has been requested is notified to PC 10_1. In the following description, the request for authorization for communication may be referred to as a "communication request." When receiving the authorization request information, PC 10_1 outputs information for allowing the presenter U_1 to determine whether or not to approve the authorization for this communication to the display unit 17 of PC 10_1. The information for allowing the presenter U_1 to determine whether or not to approve the authorization for communication between PC 10_2 and the projector 20 may be a character string indicating whether or not to approve the authorization for communication between PC 10_2 and the projector 20, or may be image data indicating an image. In the following description, the information for allowing the presenter U_1 to determine whether or not to approve the authorization for communication between PC 10_2 and the projector 20 is assumed to be image data indicating an image, and may be referred to as "communication determination image data." When the projector 20 receives from the PC 10_1 information indicating that authorization for communication between the PC 10_2 and the projector 20 has been approved, the PC 10_2 logs in to the projector 20. Since the image indicated by the communication determination image data is not displayed in the projection area PR, the presenter U_1 can smoothly proceed with his explanation of the image GP. The operation of the display system 1 will be described with reference to FIGS. 4, 5, and 6.

[0035] 1-3. Operation of Display System 1 FIG. 4 is a sequence diagram illustrating an example of the operation of the display system 1. FIG. 5 is a flowchart illustrating an example of the operation of the projector 20. In FIG. 4, the explanation is based on the assumption that the PCs 10 included in the display system 1 are PC10_1, PC10_2, and PC10_3. In the first embodiment, management authority for the projector 20 is set to the PC 10 that has logged in to the projector 20. Then, the projector 20 allows the presenter U of the PC 10 for which management authority has been set to decide whether or not to approve permission for communication with the projector 20. In the following description, the PC 10 for which management authority has been set may be referred to as the "management authority PC10_m."

[0036] In the following description, the number of the multiple PCs 10 in the display system 1 is three or more. PC10_1 corresponds to the "first device", PC10_2 corresponds to the "second device", and PC10_3 corresponds to the "third device". Communication between PC10_1 and the projector 20 corresponds to the "first communication". Communication between PC10_2 and the projector 20 corresponds to the "second communication". Communication between PC10_3 and the projector 20 corresponds to the "third communication". Presenter U_1 corresponds to the "user of the first device". Presenter U_2 corresponds to the "user of the second device".

[0037] The processing circuitry 21 of the projector 20 reads the communication control program PRM from the storage circuitry 22 and executes the read communication control program PRM to perform the operations shown in Figures 4 and 5. The processing circuitry 11 of the PC 10 reads the projector communication control program PRJ from the storage circuitry 12 and executes the read projector communication control program PRJ to perform the operations shown in Figure 4.

[0038] 4 and 5, in step SP2, after powering on, the processing circuit 21 projects an identification code image including an identification code onto the projection area PR. The identification code is, for example, a string of alphanumeric characters. Then, as shown in FIG. 5, in step SP4, the processing circuit 21 determines whether or not an instruction to turn off the power has been issued, for example, by pressing the power button of the projector 20. If the determination result in step SP4 is positive, the processing circuit 21 ends the series of processes shown in FIG. 5.

[0039] If the determination result in step SP4 is negative, the processing circuit 21 determines in step SP6 whether or not a communication request has been received from the PC 10, as shown in Fig. 5. If the determination result in step SP6 is positive, the processing circuit 21 executes a communication request reception process in step SP8, as shown in Fig. 5.

[0040] In FIG. 4, the description will be made on the assumption that after the processing circuit 21 has completed the processing of step SP2, the presenter U_1 performs an input operation, causing the PC 10_1 to transmit a communication request including an identification code to the projector 20 in step SC2.

[0041] When a communication request is received from PC10_1, which is the first PC 10, the processing circuit 21 determines that the determination result of step SP6 is positive, and executes a process upon reception of a communication request in step SP8. The process upon reception of a communication request will be described with reference to FIG. 6.

[0042] 6 is a flowchart showing an example of the process when a communication request is received. In step SP32, the processing circuit 21 determines whether or not there is a PC 10 to which administrative authority has been set.

[0043] In the example of FIG. 4, at the stage of step SC2, there is no PC 10 for which administrative authority has been set. Therefore, the processing circuit 21 determines that the determination result of step SP32 is negative. If the determination result of step SP32 is negative, as shown in FIG. 6, in step SP34, it is determined whether or not the received identification code matches the identification code included in the identification code image. If the determination result of step SP34 is negative, in step SP36, the processing circuit 21 rejects connection with the PC 10 that sent the communication request, and ends the series of processes shown in FIG. 6. Under the instruction of the processing circuit 21, the communication circuit 24 transmits a rejection response to the PC 10 that sent the communication request, as an example of rejecting connection with the PC 10. This rejection response includes, for example, an identifier indicating that the identification code entered by the user is incorrect.

[0044] 4 and 6, in step SP38, the processing circuit 21 grants login permission to PC10_1, which is the PC 10 that sent the communication request, and PC10_1 logs in to the projector 20. Next, as shown in FIG. 6, in step SP40, the processing circuit 21 sets administrative authority to the PC 10 that sent the communication request, and ends the series of processes shown in FIG.

[0045] 4 and 5. After the process of step SP8 is completed, the processing circuit 21 executes the process of step SP4 again.

[0046] If the determination result in step SP6 is negative, the processing circuit 21 determines in step SP10 whether or not reception of image data has started from the PC 10 that has logged in to the projector 20, as shown in FIG.

[0047] In the example of FIG. 4, the PC 10_1 that has logged in to the projector 20 starts transmitting image data to the projector 20 in step SC4. In the example of FIG. 4, the processing circuit 21 determines that the determination result in step SP10 is positive. If the determination result in step SP10 is positive, as shown in FIGS. 4 and 5, the projection device 27 starts projecting an image based on the received image data in step SP12 based on an instruction from the processing circuit 21. The image based on the image data may be the image itself indicated by the image data, a portion of the image indicated by the image data, or an image in which another image is superimposed on the image or a portion of the image indicated by the image data. The other image may be, for example, a character string indicating the current time, or an OSD image whose position and contrast can be manipulated. OSD is an abbreviation for On Screen Display.

[0048] In step SP12, if image data has been received from two or more PCs 10, the projection device 27 projects, into each of the divided areas of the projection area PR, an image based on the image data received from each of the two or more PCs 10. After completing the process of step SP12, the processing circuit 21 executes the process of step SP4 again.

[0049] If the determination result in step SP10 is negative, processing circuit 21 determines whether or not reception of image data has ended in step SP14, as shown in Fig. 5. If the determination result in step SP14 is positive, projection device 27 ends projection of an image based on the received image data in response to an instruction from processing circuit 21 in step SP16, as shown in Fig. 5.

[0050] In step SP16, when image data is being received from three or more PCs 10 and reception of image data from one PC 10 is completed, the projection device 27 reduces the number of divisions of the projection area PR and projects images based on the image data received from each of the two or more PCs 10. When image data is being received from two PCs 10 and reception of image data from one PC 10 is completed, the projection device 27 cancels the division of the projection area PR and projects an image based on the image data received from the remaining one PC 10.

[0051] After the process of step SP16 ends, the processing circuit 21 executes the process of step SP4 again. If the determination result of step SP14 is negative, the processing circuit 21 also executes the process of step SP4 again.

[0052] 4, the explanation is based on the assumption that, after the projection device 27 starts projecting an image in step SP12, the PC 10_2 transmits a communication request to the projector 20 in step SC6. Therefore, the processing circuit 21 determines that the determination result in step SP6 is positive, and further determines that the determination result in step SP32 in FIG. 6 is positive because there is one PC 10 for which administrative authority has been set.

[0053] 4 and 6 for the explanation. If the determination result in step SP32 is positive, the communication circuit 24, in step SP42, under the instruction of the processing circuit 21, transmits authorization request information to one or more administrative authority PC10_m, PC10_1 in the example of FIG. 4. The authorization request information is information indicating that authorization for communication between the PC10 and the projector 20 has been requested, and is information necessary for the presenter U to determine whether or not the PC10 should approve the authorization for communication with the projector 20. The authorization request information is, for example, information about the PC10 that transmitted the communication request to the projector 20. For example, the authorization request information includes the name of the PC10 that requested permission for communication and the account ID currently logged in to the PC10. ID is an abbreviation for Identification.

[0054] Upon receiving the authorization request information, the processing circuit 11 of the PC 10, in the example of Fig. 4, PC 10_1 generates communication determination image data based on the authorization request information, as shown in Fig. 4, and in step SC8 displays the communication determination image CW indicated by the communication determination image data on the display unit 17. A display example of the communication determination image CW will be described with reference to Fig. 7.

[0055] FIG. 7 is a diagram showing an example of the communication judgment image CW. As shown in FIG. 7, the display unit 17 superimposes the communication judgment image CW on the image GP_1. In the example of FIG. 7, the communication judgment image CW has a character string STR1, a button BTN1, and a button BTN2. The character string STR1 is "Do you approve the permission for communication between the projector 20 and the PC 10_2?" The button BTN1 is a button that, when pressed by the presenter U, transmits to the projector 20 approval information indicating that the permission for communication with the projector 20 has been approved. The button BTN2 is a button that transmits to the projector 20 denial information indicating that the permission for communication with the projector 20 has been denied.

[0056] As shown in FIG. 7, the communication determination image CW is displayed on the display unit 17_1, but is not projected onto the projection region PR.

[0057] Returning to FIGS. 4 and 6, the description will be made as follows. After the process of step SP42 is completed, the processing circuit 21 determines in step SP44 whether approval information or denial information has been received from any of one or more administrative authority PCs 10_m, as shown in FIG. 6. If the determination result in step SP44 is negative, the processing circuit 21 executes the process of step SP44 again. In the example of FIG. 4, the description will be made on the assumption that button BTN1 is pressed by the presenter U_1 on PC 10_1, and approval information is transmitted to the projector 20 in step SC10. Therefore, the processing circuit 21 determines that the determination result in step SP44 is positive.

[0058] If the determination result of step SP44 is positive, in step SP46, the communication circuit 24, under the instruction of the processing circuit 21, transmits determination completion information to the management authority PC10_m that has transmitted the authorization request information and has not yet transmitted either approval information or denial information, among the management authority PC10_m. If there is a management authority PC10_m that has not yet received either approval information or denial information, the projector 20 determines that this management authority PC10_m has not yet transmitted either approval information or denial information. The determination completion information is information indicating that the determination of whether to approve the authorization of communication has been completed. After processing step SC8, there is only one management authority PC10_m, and there is no management authority PC10_m that has not yet transmitted either approval information or denial information. Therefore, the processing circuit 21 does not actually execute processing in step SP46.

[0059] After completing the process of step SP46, the processing circuit 21 determines in step SP48 whether or not approval information has been received. If the determination result of step SP48 is positive, the processing circuit 21 executes the process of step SP38, and in the example of FIG. 4, grants permission to log in to PC 10_2.

[0060] If the determination result in step SP48 is negative, that is, if denial information has been received, the processing circuit 21 denies connection with the PC 10 that sent the communication request in step SP50, as shown in Fig. 6, and ends the series of processes shown in Fig. 6. The process of step SP50 is the same as the process of step SP36, but the content of the denial response in step SP50 may be different from the content of the denial response in step SP36. The denial response in step SP50 includes, for example, an identifier indicating that authorization for communication has been denied by the user of PC 10 who has administrative authority over the projector 20.

[0061] In the example of FIG. 4, it is assumed that the processing circuit 21 executes the process of step SP38 so that the PC 10_2 logs in to the projector 20, and then the PC 10_3 transmits a communication request to the projector 20 in step SC12.

[0062] When a communication request is received, the processing circuit 21 determines that the determination results of steps SP6 and SP32 are positive. Then, in step SP42, the communication circuit 24, under the instruction of the processing circuit 21, transmits authorization request information to one or more administrative authority PC10_m, PC10_1 and PC10_2 in the example of FIG. 4. In step SC14, PC10_1 displays a communication determination image CW on the display unit 17_1. The communication determination image CW displayed on the display unit 17_1 is an image for prompting the presenter U_1 to determine whether or not to approve the authorization for communication between PC10_3 and the projector 20. In step SC16, PC10_2 displays a communication determination image CW on the display unit 17_2. The communication determination image CW displayed on the display unit 17_2 is an image for prompting the presenter U_2 to determine whether or not to approve the authorization for communication between PC10_3 and the projector 20.

[0063] In the example of FIG. 4, it is assumed that the processing circuit 11_1 of PC10_1 has transmitted approval information to the projector 20 in step SC18 based on the operation of the presenter U_1. In addition, in the example of FIG. 4, it is assumed that PC10_2 has transmitted neither approval information nor denial information. Therefore, as shown in FIG. 4, the communication circuit 24 transmits determination completion information to PC10_2 under the instruction of the processing circuit 21 in step SP46. As shown in FIG. 4, when receiving the determination completion information, PC10_2 erases the communication determination image CW displayed on the display unit 17_2 in step SC20. As a result of the projector 20 receiving the approval information, as shown in FIG. 4, the processing circuit 21 grants login permission to PC10_3, which is the PC 10 that transmitted the communication request, in step SP38, and PC10_3 logs in to the projector 20.

[0064] In FIG. 4, the projector 20 gives permission for login to PC10_3 after transmitting the judgment completion information to PC10_2, but the projector 20 may send the judgment completion information to PC10_2 after giving permission for login to PC10_3.

[0065] 1-4. Summary of the first embodiment In the following description, communication between PC10_1 and the projector 20 will be referred to as first communication, communication between PC10_2 and the projector 20 will be referred to as second communication, and communication between PC10_3 and the projector 20 will be referred to as third communication, and a summary of the first embodiment will be explained.

[0066] The display system 1 in the first embodiment includes a plurality of PCs 10 and a projector 20 capable of communicating with the plurality of PCs 10. Furthermore, the display system 1 executes a communication control method for the projector 20. The projector 20, capable of projecting an image onto the projection area PR, establishes a first communication with PC 10_1 of the plurality of PCs 10 in step SP38. Furthermore, while the projector 20 is projecting an image onto the projection area PR in step SP12, if authorization for second communication is requested by PC 10_2 of the plurality of PCs 10 in step SP42, the projector 20 transmits authorization request information indicating that authorization for the second communication has been requested to PC 10_1. PC 10_1 outputs communication determination image data, which is information for allowing the presenter U_1 to determine whether to approve the authorization for the second communication, to the display unit 17_1 of PC 10_1. The display unit 17_1 is an example of an output destination of information for allowing the presenter U_1 to determine whether to approve the authorization for the second communication. When the projector 20 receives approval information indicating that the second communication has been authorized from the PC 10_1, the projector 20 establishes the second communication. According to the first embodiment, the communication determination image CW indicated by the communication determination image data is displayed on the display unit 17_1, but is not projected in the projection area PR. Therefore, the projection of the image GP_1 based on the image data transmitted from PC 10_1 is not hindered. Furthermore, PC 10_2 can log in to the projector 20. Therefore, according to the first embodiment, PC 10_2 can log in to the projector 20 while suppressing the display of the image GP_1 based on the image data transmitted from PC 10_1 from being hindered.

[0067] The number of the PCs 10 is three or more, and each of the three or more devices has a display unit 17, and a first communication and a second communication are established between the PCs 10. When the projector 20 receives a request for authorization for the third communication from PC10_3 among the three or more PCs 10 while displaying an image in the projection area PR, the projector 20 transmits authorization request information indicating that authorization for the third communication has been requested to PC10_1 and PC10_2 in step SP42. In step SC14, PC10_1 outputs communication determination image data, which is information for allowing the presenter U_1 of PC10_1 to determine whether or not to approve the authorization for the third communication, to the display unit 17_1 of PC10_1. In step SC16, PC10_2 outputs communication determination image data, which is information for allowing the presenter U_2 of PC10_2 to determine whether or not to approve the authorization for the third communication, to the display unit 17_2 of PC10_2. In step SP44, when the projector 20 receives approval information indicating that the authorization for the third communication has been approved from at least one of the PCs 10_1 and 10_2, the projector 20 establishes the third communication. According to the first embodiment, PC10_3 can establish communication with the projector 20 while preventing the display of image GP_1 based on image data transmitted from PC10_1 from being interrupted. Furthermore, it is sufficient for either presenter U_1 or presenter U_2 to press button BTN1 or button BTN2 on the communication determination image CW. Therefore, according to the first embodiment, compared to the mode in which one presenter U presses button BTN1 or button BTN2 on the communication determination image CW, it is possible to prevent delays in approval of authorization for the third communication due to malfunctions such as delays in communication in the display system 1 or carelessness on the part of presenter U.

[0068] In addition, in response to receiving approval information indicating that the authorization for the third communication has been approved or denial information indicating that the authorization for the third communication has not been approved from one of PC10, PC10_1 and PC10_2, the projector 20 transmits, in step SP46, to the other PC10, PC10_1 and PC10_2, judgment completion information indicating that the judgment on whether to approve the authorization for the third communication has been completed. According to the first embodiment, since judgment completion information is sent to the other PC 10, the communication judgment image CW displayed on the display unit 17 of the other PC 10 can be erased, thereby reducing the operational burden on the presenter U of the other PC 10.

[0069] In the first embodiment, if the determination result in step SP44 is positive, the projector 20 transmits, in step SP46, determination completion information to the management authority PC 10_m to which neither the approval information nor the denial information has been transmitted, but this is not limited to this. For example, if the projector 20 receives approval information, the projector 20 may transmit determination completion information to the above-mentioned management authority PC 10_m after establishing communication with the PC 10 that transmitted the communication request. Also, if the projector 20 receives denial information, the projector 20 may transmit determination completion information to the above-mentioned management authority PC 10_m after refusing to connect to the PC 10 that transmitted the communication request.

[0070] 2. Variations The above-described embodiments can be modified in various ways. Specific modifications that can be applied to the above-described embodiments are exemplified below. Two or more embodiments arbitrarily selected from the following examples can be combined as appropriate within the scope of not mutually contradictory.

[0071] 2-1. First modified example In the first embodiment, when there are two or more administrative authority PCs 10_m, the projector 20 transmits authorization request information to all of the administrative authority PCs 10_m. On the other hand, in the first modified example, when there are two or more administrative authority PCs 10_m, the projector 20 transmits authorization request information to a PC 10 different from the PC 10 that is causing the projector 20 to project an image. The first modified example will be described below.

[0072] 2-1-1. Operation of the first modified example Fig. 8 is a flowchart showing an example of the operation of projector 20 in the first modified example. Compared to the flowchart shown in Fig. 5, the flowchart shown in Fig. 8 differs from the flowchart shown in Fig. 5 in that it executes the process of step SP18 when the determination result of step SP10 is positive, executes the process of step SP20 when the determination result of step SP14 is positive, and executes step SP8A instead of step SP8, but the other parts are the same. Hereinafter, only the differences from the flowchart shown in Fig. 5 will be described.

[0073] If the determination result in step SP10 is positive, in step SP18, the processing circuit 21 of the projector 20 sets the PC 10 that transmitted the image data to the shared mode. The shared mode is a mode in which the projector 20 displays an image based on image data transmitted from one or more of the three or more PCs 10 included in the display system 1. In the following description, an image based on image data transmitted from one or more PCs 10 may be referred to as a "shared image." The PC 10 that transmitted the image data representing the shared image may be referred to as a "sharer PC 10_c." Of the two or more administratively authorized PCs 10_m, a PC 10 that is not the sharer PC 10_c may be referred to as an "unshared PC 10_d." The display unit 17 of the sharer PC 10_c may be referred to as a "display unit 17_c," and the presenter U of the sharer PC 10_c may be referred to as a "presenter U_c." The display unit 17 of the unshared PC 10_d may be referred to as a "display unit 17_d."

[0074] The shared mode is an example of a "first mode." The shared image is an example of a "first image." If there are two administrative authority PCs 10_m, the sharing source PC 10_c is an example of "one device," and the unshared PC 10_d is an example of "the other device."

[0075] There are two modes of a shared image, as follows. In the first mode, the shared image is the same as the image displayed on the display unit 17_c of the sharing source PC 10_c. Hereinafter, the shared image in the first mode may be referred to as a "mirrored image."

[0076] The shared image in the second mode is different from the image displayed on the display unit 17_c of the sharing source PC 10_c. Specifically, the shared image in the second mode is a partial image of the image displayed on the display unit 17_c. The partial image displayed on the display unit 17_c is, for example, an enlarged image of a portion of the image displayed on the display unit 17_c, or an image in a window of an application program displayed on the display unit 17_c. Any type of application program may be used, and examples include a program for creating documents and a program for displaying documents. Hereinafter, the shared image in the second mode may be referred to as a "partially shared image."

[0077] After completing the process of step SP18, the processing circuit 21 ends the process of step SP12.

[0078] If the determination result in step SP14 is positive, the processing circuit 21 cancels the shared mode of the PC 10 in step SP20.

[0079] If the determination result in step SP6 is positive, the processing circuit 21 executes a process when a communication request is received in the first modified example in step SP8 A. The process when a communication request is received in the first modified example will be described with reference to FIG.

[0080] Fig. 9 is a flowchart showing an example of processing when a communication request is received in the first modified example. The flowchart shown in Fig. 9 differs from the flowchart shown in Fig. 6 in that the processing of step SP52 is executed when the determination result of step SP32 is positive, and the processing of step SP54 or step SP56 is executed after the processing of step SP52 is completed, but the other parts are the same. Hereinafter, only the differences from the flowchart shown in Fig. 6 will be explained.

[0081] If the determination result of step SP32 is positive, the processing circuit 21 determines in step SP52 whether there are two or more management authority PCs 10_. If the determination result of step SP52 is positive, the communication circuit 24, under the instruction of the processing circuit 21, transmits authorization request information to the unshared PC 10_d among the two or more management authority PCs in step SP54. On the other hand, if the determination result of step SP52 is negative, the communication circuit 24, under the instruction of the processing circuit 21, transmits authorization request information to the management authority PC 10_m in step SP56. After completing the processing of step SP54 or step SP56, the processing circuit 21 executes the processing of step SP44.

[0082] 2-1-2. Summary of the first modified example In the following description, communication between PC10_1 and projector 20 will be referred to as first communication, communication between PC10_2 and projector 20 will be referred to as second communication, and communication between PC10_3 and projector 20 will be referred to as third communication, and a summary of the first variant will be explained using an example in which PC10_1 and PC10_2 are set as administrative authority PCs.

[0083] In the display system 1 according to the first modification, the number of PCs 10 is three or more, each of which has a display unit 17. First and second communications are established between the PCs 10_1 and 10_2, and one of the PCs 10_1 and 10_2 is set to the sharing mode. That is, one of the PCs 10 is a sharing source PC 10_c. The sharing source PC 10_c is an example of a "one device." If, while displaying a shared image in the projection area PR, the projector 20 receives a request for authorization for third communication from PC 10_3 of the three or more PCs 10, the projector 20 notifies the unshared PC 10_d of authorization request information indicating that authorization for the third communication has been requested in step SP52. The unshared PC 10_d is an example of a "other device." The unshared PC 10_d outputs communication determination image data, which is information for allowing the user of the other device to determine whether to approve the authorization for the third communication, to the display unit 17_d of the unshared PC 10_d. When the projector 20 receives approval information indicating that the authorization for the third communication has been approved from the unshared PC 10_d, the projector 20 establishes the third communication. According to the first variant example, the display unit 17_d of the unshared PC 10_d, which is not causing the projector 20 to project an image, displays the communication judgment image CW indicated by the communication judgment image data, thereby not bothering the presenter U_c of the sharing source PC 10_c, which is displaying an image on the projector 20.

[0084] Furthermore, the mirrored image, which is the shared image in the first mode, is the same as the image displayed on the display unit 17_c of the sharing source PC 10_c. Since the presenter U_c of the sharing source PC 10_c may give an explanation while looking at the image displayed on the display unit 17_c, if the communication determination image CW is displayed on the display unit 17_c, the explanation regarding the image displayed on the display unit 17_c will be interrupted, which may be bothersome to the presenter U_c. Therefore, according to the first modification, it is possible to prevent the communication determination image CW from being displayed on the same image as the image projected by the projector 20, thereby preventing the presenter U_c from feeling bothered.

[0085] Furthermore, the partial shared image, which is the shared image in the second mode, is different from the image displayed on the display unit 17_c of the sharing source PC 10_c. The display unit 17_c may display a related image related to the image projected by the projector 20. This related information may be, for example, one or both of an image showing a manuscript that the presenter U_c will read out for explanation purposes and an image showing a timer for keeping the presenter U_c within the allotted time. If the communication determination image CW were to be displayed on the display unit 17_c, the related image would be hidden by the communication determination image CW, which may be bothersome to the presenter U_c. According to the first modification, the communication determination image CW can be prevented from being superimposed on the related image, thereby preventing the presenter U_c from feeling bothered.

[0086] 2-2. Second modified example The second modified example differs from the first embodiment and the first modified example in that, when the sharing source PC 10_c is in a mode in which it occupies the projection area PR and displays an image, a PC 10 that has newly logged in to the projector 20 refuses to allow the projector 20 to display an image. The second modified example will be described below.

[0087] 2-2-1. Operation of the second modified example Fig. 10 is a flowchart showing an example of the operation of projector 20 in the second modified example. Compared to the flowchart shown in Fig. 8, the flowchart shown in Fig. 10 differs from the flowchart shown in Fig. 8 in that the processing of step SP10B is executed instead of the processing of step SP10, the processing of step SP22 is executed when the determination result of step SP10B is positive, and the processing of step SP20B is executed instead of the processing of step SP20, but the other parts are the same. Hereinafter, only the differences from the flowchart shown in Fig. 8 will be described.

[0088] If the determination result of step SP6 is negative, in step SP10B, processing circuit 21 determines whether reception of image data has started or whether presenter U of PC 10 has instructed PC 10 to transition to exclusive mode. Exclusive mode is a mode in which an image based on image data transmitted from one of the three or more PCs 10 included in display system 1 is displayed in the projection area PR. In the following description, a PC 10 set to exclusive mode may be referred to as an "occupied PC 10_o." Note that exclusive mode is an example of a "second mode." An instruction to transition to exclusive mode is, for example, pressing a "Transition to exclusive mode" button displayed on display unit 17 of PC 10.

[0089] If the determination result of step SP10B is negative, processing circuit 21 executes the process of step SP14. If the determination result of step SP10B is positive, processing circuit 21 executes the process upon receiving image data in step SP22. The process upon receiving image data will be described with reference to FIG. 11.

[0090] Fig. 11 is a flowchart showing an example of the image data reception process. In the flowchart shown in Fig. 11, the process of step SP18 and the process of step SP12 are the same as the process of step SP18 and the process of step SP12 in the flowchart shown in Fig. 8, respectively, so a description of the process will be omitted. Note that, hereinafter, if the step number is the same as that already explained, the description will be omitted assuming that it has already been explained.

[0091] In step SP62, the processing circuit 21 determines whether or not any of the three or more PCs 10 included in the display system 1 has been set to the occupancy mode.

[0092] If the determination result in step SP62 is negative, then in step SP64, the processing circuit 21 determines whether or not a command to switch to the occupancy mode has been issued. If the determination result in step SP64 is negative, then the processing circuit 21 executes the process of step SP18. After completing the process of step SP18, the projection device 27 executes the process of step SP12. After completing the process of step SP12, the processing circuit 21 ends the series of processes shown in FIG. 11.

[0093] If the determination result in step SP64 is positive, the processing circuit 21 sets the PC 10 instructed to switch to the exclusive mode to the exclusive mode in step SP66. Next, in step SP68, the projection device 27 starts projecting an image based on the received image data while occupying the projection area PR based on the instruction from the processing circuit 21. Specifically, if image data has been received from two or more PCs 10, the projection device 27 cancels the division of the projection area PR and projects an image based on the image data transmitted from the PC 10 set to the exclusive mode, i.e., the occupied PC 10_o. After completing the processing of step SP68, the processing circuit 21 ends the series of processes shown in FIG. 11.

[0094] If the determination result in step SP62 is positive, in step SP70, the processing circuit 21 refuses to project an image based on image data received from a PC 10 other than the occupied PC 10_o. After completing the processing of step SP70, the processing circuit 21 ends the series of processes shown in FIG.

[0095] Returning to Fig. 10 for the explanation, if the determination result of step SP14 is positive, the processing circuit 21 cancels the PC 10 that was set to the shared mode or the exclusive mode in step SP20B. Specifically, if the PC 10 that has finished receiving the image data is the sharing source PC 10_c, the processing circuit 21 cancels the shared mode, and if the PC 10 that has finished receiving the image data is the exclusive PC 10_o, the processing circuit 21 cancels the exclusive mode. After the processing of step SP20B is completed, the processing circuit 21 executes step SP16.

[0096] To avoid cluttering the diagram, FIG. 10 does not illustrate a case where presenter U of PC 10 issues an instruction to cancel the exclusive mode. When presenter U of PC 10 issues an instruction to cancel the exclusive mode, projector 20 cancels the exclusive mode that PC 10 has been set to. The instruction to cancel the exclusive mode is, for example, when a "Cancel Occupancy Mode" button displayed on display unit 17 of PC 10 is pressed. If image data is received from two or more PCs 10 as a result of canceling the exclusive mode, projection device 27 projects images based on the image data received from each of the two or more PCs 10 into each of the divided areas of projection area PR.

[0097] 2-2-2. Summary of the second modified example In the following description, communication between PC10_1 and projector 20 will be referred to as first communication, communication between PC10_2 and projector 20 will be referred to as second communication, and communication between PC10_3 and projector 20 will be referred to as third communication, and a summary of the second variant will be explained using an example in which PC10_1 and PC10_2 are set as administrative authority PCs.

[0098] In the display system 1 in the second modified example, the number of the PCs 10 is three or more, each of which has a display unit 17, and which has established first and second communications. One of PCs 10_1 and PC 10_2 is set to an exclusive mode. The one of PCs 10 is an example of a "one device." When PC 10_3, one of the three or more PCs 10, requests authorization for third communication while the projector 20 is displaying an image in the projection area PR, the projector 20 notifies the unshared PC 10_d of authorization request information indicating that authorization for the third communication has been requested. The unshared PC 10_d is an example of a "other device." The unshared PC 10_d outputs communication determination image data, which is information for allowing the user of the other device to determine whether to approve the authorization for the third communication, to the display unit 17_d of the unshared PC 10_d. When the projector 20 receives approval information from the unshared PC 10_d indicating that authorization for the third communication has been approved, the projector 20 establishes the third communication. After establishing the third communication, when the projector 20 is requested to display an image based on image data transmitted from another PC 10 other than the PC 10 set to the exclusive mode among the three or more PCs 10, the projector 20 refuses to allow the projector 20 to display an image based on image data transmitted from the other PC 10 in step SP70. In this example, the other PC 10 is the other PC 10 and PC 10_3. The other PC 10 is an example of an "other device." According to the second modification, by setting the exclusive mode, even if a presenter U of a PC 10 not in the exclusive mode erroneously operates the PC 10, it is possible to prevent an image based on image data transmitted from the PC 10 not in the exclusive mode from being projected onto the projection area PR. An example of an erroneous operation will be described below. Assume that the display system 1 includes four PCs 10, PC 10_1 is the exclusive PC 10_o, PC 10_2 and PC 10_3 are the unshared PCs 10_d, and communication between PC 10_4 and the projector 20 has not been established. Under this assumption, when PC 10_4 transmits a communication request with the projector 20 to the projector 20, the projector 20 transmits authorization request information to PC 10_2 and PC 10_3. A situation may occur in which presenter U_3 presses either button BTN1 or button BTN2 of the communication determination image CW immediately before presenter U_2 attempts to press either button BTN1 or button BTN2 of the communication determination image CW. In this situation, the projector 20 transmits determination completion information to the PC 10_2, and the communication determination image CW displayed on the display unit 17_2 is erased. Therefore, the presenter U_2 may erroneously press an operation button superimposed on the communication determination image CW while attempting to press either the button BTN1 or the button BTN2 on the communication determination image CW. Even if such an erroneous operation occurs, according to the second modification, it is possible to prevent an image based on image data transmitted from a PC 10 in a mode other than the exclusive mode from being projected onto the projection area PR.

[0099] 2-3.Third modified example The third modified example differs from the second modified example in that it is possible to set a mode in which the image displayed on the projector 20 is not updated. The third modified example will be described below.

[0100] 2-3-1. Operation of the third modified example Fig. 12 is a flowchart showing an example of the operation of projector 20 in the third modified example. Compared to the flowchart shown in Fig. 10, the flowchart shown in Fig. 12 differs from the flowchart shown in Fig. 10 in that the process of step SP8C is executed instead of the process of step SP8A, the process of step SP10C is executed instead of the process of step SP10B, and the process of step SP22C is executed instead of the process of step SP22, but the other parts are the same. Hereinafter, only the differences from the flowchart shown in Fig. 10 will be described.

[0101] For ease of explanation, the processing of step SP8C will be explained after the processing of step SP20C. If the determination result of step SP6 is negative, in step SP10C, the processing circuit 21 determines whether reception of image data has started or whether a command to switch to hold mode has been issued by the presenter U of the PC 10. The hold mode is a mode in which the image displayed on the projector 20 is not updated. An instruction to switch to hold mode is issued, for example, by pressing a "Switch to Hold Mode" button displayed on the display unit 17 of the PC 10.

[0102] The hold mode, in which the image displayed on the projector 20 is not updated, includes continuously updating the same image. In the following description, the PC 10 set to the hold mode may be referred to as the "hold PC 10_s." The hold mode is an example of the "third mode."

[0103] The hold mode is useful when the presenter U wants the PC 10 to execute a process during the share mode that he does not want the audience W to see. An example of a process that the presenter U does not want the audience W to see is a process of entering personal information such as an account ID and password.

[0104] To achieve the hold mode, the projector 20 stops updating images based on image data after the hold mode is set. In the following description, the image data after the hold mode is set may be referred to as "post-hold image data."

[0105] There are three methods for realizing the hold mode, as shown below. In the first method for realizing the hold mode, when the hold mode is instructed by the presenter U, the hold PC 10_s temporarily stops sending image data to the projector 20. The projector 20 continues to project an image based on the image data last sent from the hold PC 10_s. In other words, in the first method for realizing the hold mode, the hold PC 10_s does not send image data to the projector 20 after the hold.

[0106] In a second method for realizing the hold mode, when the presenter U instructs the hold mode, the hold PC 10_s temporarily stops transmitting image data to the projector 20. The projector 20 continues to project an image indicated by image data pre-stored in the memory circuitry 22. That is, in the second method for realizing the hold mode, the hold PC 10_s does not transmit image data after the hold to the projector 20. The image indicated by the image data pre-stored in the memory circuitry 22 may be any image, for example, an image including a character string indicating the hold mode. Note that the image indicated by the image data pre-stored in the memory circuitry 22 may also be a moving image.

[0107] In a third method for realizing the hold mode, the hold PC 10_s continues to transmit image data to the projector 20 even when the presenter U instructs the hold mode. The projector 20 stores the image data transmitted from the hold PC 10_s at the time the presenter U instructs the hold mode in the storage circuit 22, and continues to project an image based on the stored image data. That is, in a second method for realizing the hold mode, the hold PC 10_s transmits post-hold image data to the projector 20, but the projector 20 does not project an image based on the post-hold image data. The following description will be given using an embodiment that employs the first method for realizing the hold mode.

[0108] If the determination result in step SP10C is positive, the processing circuit 21 executes the image data reception process in the third modified example in step SP22C. The image data reception process in the third modified example will be described with reference to FIG.

[0109] 13 is a flowchart showing an example of the operation of the image data reception process in the third modified example. In step SP72, the processing circuit 21 determines whether or not a command to switch to the hold mode has been issued. If the determination result in step SP72 is negative, the processing circuit 21 executes the process of step SP18. After the process of step SP18 is completed, the projection device 27 executes the process of step SP12. After the process of step SP12 is completed, the processing circuit 21 ends the series of processes shown in FIG. 13.

[0110] If the determination result in step SP72 is positive, the processing circuit 21 sets the PC 10 instructed to transition to the hold mode to the hold mode in step SP74. After the processing of step SP74 is completed, the projection device 27 projects an image in a state not based on the image data transmitted from the hold PC 10_s, based on the instruction of the processing circuit 21, in step SP76. After the processing of step SP76 is completed, the processing circuit 21 ends the series of processes shown in Fig. 13. The state immediately before the change to the hold mode will be described using Fig. 14, and the state after the change to the hold mode will be described using Fig. 15.

[0111] FIG. 14 is a diagram illustrating the state immediately before being changed to the hold mode. FIG. 15 is a diagram illustrating the state after being changed to the hold mode. A common premise between FIG. 14 and FIG. 15 is that PC10_1 and PC10_2 are the sharing source PC10_c. Therefore, the projector 20 divides the projection area PR into two partial areas, SR1 and SR2. The partial areas SR1 and SR2 may be areas obtained by dividing the projection area PR into two equal parts, or may be areas obtained by dividing the projection area PR into two unequal parts. Furthermore, the projection area PR may include an area that is not included in either the partial area SR1 or the partial area SR2.

[0112] In the example of FIG. 14, the projector 20 projects an image GC_A1 based on image data transmitted from PC 10_1 onto the partial region SR1, and projects an image GC_B1 based on image data transmitted from PC 10_2 onto the partial region SR2. The image GC_A1 is the same as the image GP_A1 displayed on the display unit 17_1. The image GC_B1 is the same as the image GP_B1 displayed on the display unit 17_2. As such, the example of FIG. 14 is based on the assumption that a shared image in the first mode, i.e., a mirrored image, is projected before the mode is changed to the hold mode. Note that the partial region SR1 is an example of a "first partial region," and the partial region SR2 is an example of a "second partial region." The image data transmitted from PC 10_1 is an example of the "first image data," and the image data transmitted from PC 10_2 is an example of the "second image data."

[0113] In the state shown in FIG. 14, it is assumed that the presenter U_1 instructs the PC 10_1 to change from the share mode to the hold mode.

[0114] In the example of Fig. 15, the projector 20 stops updating the image of the partial region SR1 based on the image data after PC 10_1 is set to the hold mode. Therefore, in the example of Fig. 15, the image displayed on the display unit 17_1 is updated from image GP_A1 to image GP_A2, but the image projected in the partial region SR1 remains as image GC_A1. On the other hand, for PC 10_2, which remains in the share mode, the projector 20 continues updating the image of the partial region SR2. That is, in the example of Fig. 15, the image displayed on the display unit 17_2 is updated from image GP_B1 to image GP_B2, and the image projected in the partial region SR2 is updated from image GC_B1 to image GC_B2, and the image GP_B2 and the image GC_B2 are the same.

[0115] Returning to FIG. 12 for the explanation, if the determination result of step SP10C is negative, the processing circuit 21 executes the processing of step SP14. If the determination result of step SP14 is positive, the processing circuit 21 cancels the PC 10 that was set to the share mode or the hold mode in step SP20C. Specifically, if the PC 10 that has finished receiving the image data is the share source PC 10_c, the processing circuit 21 cancels the share mode, and if the PC 10 that has finished receiving the image data is the hold PC 10_s, the processing circuit 21 cancels the hold mode. As a result of canceling the hold mode, the projector 20 resumes updating the image based on the image data transmitted from the PC 10 after the hold mode was canceled. After the processing of step SP20C is completed, the processing circuit 21 executes step SP16.

[0116] To avoid complicating the diagram, Fig. 12 does not illustrate a case where presenter U of PC 10 issues an instruction to cancel the hold mode. When presenter U of PC 10 issues an instruction to cancel the hold mode, projector 20 cancels the hold mode of PC 10.

[0117] If the determination result of step SP6 is positive, the processing circuit 21 executes a communication request reception process in the third modified example in step SP8C. The communication request reception process in the third modified example differs from the flowchart shown in Fig. 6 in that authorization request information transmission process is executed instead of the process of step SP42 shown in Fig. 6, but the other parts are the same. Therefore, the communication request reception process in the third modified example will not be illustrated, and the authorization request information transmission process will be described using Fig. 16.

[0118] Fig. 16 is a flowchart showing an example of authorization request information transmission processing. If the determination result of step SP52 is negative, the processing circuit 21 executes processing of step SP56 and ends the series of processing shown in Fig. 16. If the determination result of step SP52 is positive, the processing circuit 21 determines in step SP82 whether or not one or both of a reserved PC 10_s and an unshared PC 10_d are present among the three or more PCs 10 included in the display system 1.

[0119] If the determination result in step SP82 is positive, the communication circuit 24, under the instruction of the processing circuit 21, transmits authorization request information to the PC 10 found in step SP82 in step SP84. Specifically, if both the reserved PC 10_s and the unshared PC 10_d are present, the communication circuit 24 transmits authorization request information to both the reserved PC 10_s and the unshared PC 10_d. If only the reserved PC 10_s is present, the communication circuit 24 transmits authorization request information to the reserved PC 10_s, and if only the unshared PC 10_d is present, the communication circuit 24 transmits authorization request information to the unshared PC 10_d. For example, if the reserved PC 10_s receives the authorization request information, the reserved PC 10_s displays a communication determination image CW on the display unit 17_s. After completing the processing of step SP84, the processing circuit 21 terminates the series of processes shown in FIG. 16.

[0120] If the determination result in step SP82 is negative, the communication circuit 24 transmits authorization request information to the sharing source PC 10_c in step SP86 under the instruction of the processing circuit 21. After completing the processing of step SP86, the processing circuit 21 ends the series of processing shown in FIG.

[0121] 2-3-2. Summary of the third modified example In the following description, communication between PC10_1 and the projector 20 will be referred to as first communication, communication between PC10_2 and the projector 20 will be referred to as second communication, communication between PC10_3 and the projector 20 will be referred to as third communication, image data transmitted from PC10_1 will be referred to as first image data, and image data transmitted from PC10_2 will be referred to as second image data. Furthermore, in the following description, a summary of the third modified example will be explained using an example in which PC10_1 and PC10_2 are set as administrative authority PCs.

[0122] In the display system 1 in the third modified example, the number of the PCs 10 is three or more, and each of the three or more PCs 10 has a display unit 17, and first and second communications are established between the PCs 10_1 and 10_2. Both PCs 10_1 and 10_2 are set to a shared mode. An image based on first image data transmitted from PC 10_1 is displayed in a partial region SR1 that is a part of the projection area PR, and an image based on second image data transmitted from PC 10_2 is displayed in a partial region SR2 that is a part of the projection area PR and different from the partial region SR1. When PC 10_1 is set to a hold mode in which the image displayed on the projector 20 is not updated, the projector 20 stops updating the image in the partial region SR1 based on the first image data after the hold mode was set. When PC 10_2 is set to the hold mode, the projector 20 stops updating the image in the partial region SR2 based on the second image data after the hold mode was set. When the projector 20 receives a request for authorization for the third communication from PC 10_3 among the three or more PCs 10 while displaying an image in the projection area PR, the projector 20 transmits authorization request information indicating that authorization for the third communication has been requested to the PC 10 set to the reserved mode, i.e., the reserved PC 10_s. The reserved PC 10_s outputs communication determination image data, which is information for allowing the presenter U of the reserved PC 10_s to determine whether or not to approve the authorization for the third communication, to the display unit 17_s of the reserved PC 10_s. When the projector 20 receives approval information indicating that the authorization for the third communication has been approved from the reserved PC 10_s, it establishes the third communication. According to the third variant, by sending authorization request information to the reserved PC 10_s, communication between the PC 10_3 and the projector 20 can be established while preventing the image displayed on the display unit 17 of the sharing source PC 10_c from being disturbed.

[0123] 2-4.Fourth Modification The fourth modification differs from the first modification in that the authorization request information is prevented from being transmitted to the sharing source PC 10_c that transmits image data showing a mirrored image. The fourth modification will be described below.

[0124] 2-4-1. Operation of the fourth modified example In the fourth variant, in the processing upon receiving a communication request in the first variant shown in FIG. 9, instead of executing the processing of step SP52, the processing of step SP54, and the processing of step SP56, the authorization request information transmission processing in the fourth variant shown in FIG. 17 is executed.

[0125] Fig. 17 is a flowchart showing an example of authorization request information transmission processing in the fourth modified example. If the determination result in step SP52 is negative, the processing circuit 21 executes processing in step SP56 and ends the series of processing shown in Fig. 17. If the determination result in step SP52 is positive, the processing circuit 21 determines in step SP92 whether or not there is a sharing source PC 10_c and / or an unshared PC 10_d that transmits a partially shared image among the three or more PCs 10 included in the display system 1.

[0126] The connection protocol that defines the method of transmitting image data defines a field for setting an identifier that indicates whether the shared image represented by the image data transmitted by PC 10 is a mirrored image or a partially shared image. By referring to the identifier set in this field, processing circuitry 21 can determine whether the shared image represented by the image data transmitted by PC 10 is a mirrored image or a partially shared image.

[0127] If the determination result in step SP92 is positive, the communication circuit 24, under the instruction of the processing circuit 21, transmits authorization request information to the PC 10 found in step SP92 in step SP94. Specifically, if both the sharing source PC 10_c and the unshared PC 10_d that will transmit the partially shared image are present, the communication circuit 24 transmits authorization request information to the sharing source PC 10_c that will transmit the partially shared image and the unshared PC 10_d. If only the sharing source PC 10_c that will transmit the partially shared image is present, the communication circuit 24 transmits the authorization request information to the sharing source PC 10_c that will transmit the partially shared image, and if only the unshared PC 10_d is present, the communication circuit 24 transmits the authorization request information to the unshared PC 10_d. For example, if the sharing source PC 10_c that will transmit the partially shared image receives the authorization request information, the sharing source PC 10_c that will transmit the partially shared image displays a communication determination image CW on the display unit 17_s. After completing the processing of step SP94, the processing circuit 21 terminates the series of processes shown in FIG. 17.

[0128] If the result of the determination in step SP92 is negative, the processing circuit 21 executes the process of step SP86 and ends the series of processes shown in FIG.

[0129] 2-4-2. Summary of the fourth modification In the following description, for the sake of simplicity, communication between PC10_1 and the projector 20 will be referred to as first communication, communication between PC10_2 and the projector 20 will be referred to as second communication, communication between PC10_3 and the projector 20 will be referred to as third communication, image data transmitted from PC10_1 will be referred to as first image data, and image data transmitted from PC10_2 will be referred to as second image data. Furthermore, in the following description, a summary of the fourth modified example will be explained using an example in which PC10_1 and PC10_2 are set as administrative authority PCs.

[0130] In the display system 1 of the fourth modification, there are three or more PCs 10, each of which has a display unit 17. First and second communications are established, and both PCs 10_1 and 10_2 are set to a sharing mode. An image displayed on the projector 20 by one of PCs 10_1 and 10_2 is a mirrored image, and an image projected on the projector 20 by the other of PCs 10_1 and 10_2 is a partially shared image. When the projector 20 receives a request for authorization for third communications from PC 10_3 of the three or more PCs 10 while displaying an image in the projection area PR, the projector 20 notifies the other PC 10 that authorization for third communications has been requested. The other PC 10 outputs communication determination image data, which is information for allowing the presenter U of the other PC 10 to determine whether to approve authorization for the third communications, to the display unit 17 of the other PC 10. When the projector 20 receives approval information from the other PC 10 indicating that the authorization for the third communication has been approved, the projector 20 establishes the third communication. According to the fourth modified example, by transmitting authorization request information to the sharer PC 10_c that causes the projector 20 to project the partial shared image, communication between PC 10_3 and the projector 20 can be established while preventing the display of the mirrored image displayed on the display unit 17 of the sharer PC 10_c from being interrupted. Furthermore, because the image displayed on the display unit 17 of the sharer PC 10_c that projects the partial shared image includes a portion that is different from the partial shared image, there is a possibility that the communication determination image CW will be displayed in a position that will not be bothersome to the presenter U_c of the sharer PC 10_c that projects the partial shared image. Therefore, according to the fourth modified example, it is possible to reduce the possibility that the presenter U_c will feel bothered, compared to an aspect in which authorization request information is transmitted to PC 10_c that causes the projector 20 to project the mirrored image.

[0131] 2-5. Fifth Modification In the above-described embodiments, the projector 20 is an example of a "display device," but the present invention is not limited to this. For example, other examples of the display device may be an organic EL display or a liquid crystal display. EL is an abbreviation for Electro Luminescence.

[0132] 2-6. Sixth Modification In the above-described embodiments, the display unit 17 of the PC 10 is shown as an example of an output destination of information for allowing the presenter U_1 to decide whether to approve the permission for communication. However, the output destination is not limited to the display unit 17. For example, the PC 10 may have earphones, and the presenter U may wear the earphones. The PC 10 may play, through the earphones, audio indicating information for allowing the presenter U_1 to decide whether to approve the permission for communication between the PC 10 and the projector 20, and audio prompting the presenter U_1 to approve or deny the permission for communication. For example, the audio indicating information for allowing the presenter U_1 to decide whether to approve the permission for communication between the PC 10 and the projector 20 is, "Do you approve the permission for communication between the projector 20 and PC 10_2?". The audio prompting the presenter U_1 to approve or deny the permission for communication is, for example, "If you approve the permission for communication, press the enter key. If you deny the permission, press the cancel key." When the enter key is pressed, the PC 10 transmits approval information to the projector 20, and when the cancel key is pressed, the PC 10 transmits disapproval information to the projector 20.

[0133] 2-7. Seventh Variation In each of the above-described aspects, the projector 20 transmitted judgment completion information to the management authority PC 10_m that transmitted the authorization request information and to which the management authority PC 10_m has not transmitted both the approval information and the denial information, but it is not necessary to transmit the judgment completion information.

[0134] 2-8. Eighth Variation In the first modified example and the example based on the first modified example, the shared image in the second example is a partial image of the image displayed on the display unit 17_c, but is not limited to this. For example, the shared image in the second example may be an image in which another image is superimposed on the image displayed on the display unit 17_c.

[0135] 3. Notes A summary of this disclosure is provided below.

[0136] (Supplementary Note 1) A communication control method for a display device in a display system having a plurality of devices and a display device capable of communicating with the plurality of devices, wherein the display device capable of displaying an image in its display area establishes a first communication with a first device of the plurality of devices, and when the display device receives a request for authorization of a second communication between the second device and the display device from a second device of the plurality of devices while displaying the image in its display area, the display device transmits information to the first device indicating that authorization for the second communication has been requested, the first device outputs information to the first device for allowing a user of the first device to decide whether to approve the authorization for the second communication, and the display device establishes the second communication when it receives information from the first device indicating that the authorization for the second communication has been approved. Supplementary Note 1 enables the communication between the second device and the display device to be established while preventing interference with the display of an image in its display area based on image data transmitted from the first device.

[0137] (Supplementary Note 2) A communication control method for a display device as described in Supplementary Note 1, wherein the plurality of devices are three or more devices, each of the three or more devices having a display unit, the first communication and the second communication are established, and when a third device among the three or more devices requests authorization for a third communication between the third device and the display device while the display device is displaying an image in the display area, the display device transmits information indicating that authorization for the third communication has been requested to the first device and the second device, the first device outputs information to the display unit of the first device for allowing a user of the first device to decide whether or not to approve the authorization for the third communication, and the second device outputs information to the display unit of the second device for allowing a user of the second device to decide whether or not to approve the authorization for the third communication, and when the display device receives information indicating that the authorization for the third communication has been approved from at least one of the first device and the second device, the display device establishes the third communication. According to Appendix 2, compared to a configuration in which one user decides whether to approve the authorization of the third communication, delays in approval of the third communication due to malfunctions such as delays in communication in the display system or user negligence can be reduced.

[0138] (Supplementary Note 3) A communication control method for a display device as described in Supplementary Note 1, wherein the plurality of devices are three or more devices, each of the three or more devices having a display unit, the first communication and the second communication are established, one of the first device and the second device is set to a first mode in which a first image based on image data transmitted from one or more of the three or more devices is displayed on the display device, and when the display device receives a request for authorization of a third communication between the third device and the display device from a third device of the three or more devices while displaying the first image in the display area, the display device transmits information indicating that authorization of the third communication has been requested to the other device, and the other device outputs information to the display unit of the other device to allow a user of the other device to decide whether or not to approve the authorization of the third communication, and when the display device receives information from the other device indicating that the authorization of the third communication has been approved, the display device establishes the third communication. According to Appendix 3, the other device that is not displaying an image on its display device outputs information to its display unit to allow the user of the other device to decide whether or not to approve the authorization for the third communication, thereby preventing the user of the one device that is displaying an image on its display device from being inconvenienced.

[0139] (Supplementary Note 4) In a fourth aspect that is a preferred example of the third aspect, the method for controlling communication with a display device according to Supplementary Note 3, wherein the first image is the same as the image displayed on the display unit of the one device. According to Supplementary Note 4, it is possible to prevent information for prompting the user of the one device to decide whether or not to approve the authorization of the third communication from being displayed on the same image as the image displayed by the display device, thereby preventing the user of the one device from feeling annoyed.

[0140] (Supplementary Note 5) The communication control method for a display device according to Supplementary Note 3, wherein the first image is different from the image displayed on the display unit of the one device. According to Supplementary Note 5, it is possible to prevent information for prompting the user of the one device to decide whether or not to approve the authorization of the third communication from being superimposed on information about the image projected on the display device, thereby preventing the user of the one device from feeling annoyed.

[0141] (Supplementary Note 6) The plurality of devices are three or more devices, each of the three or more devices having a display unit, the first communication and the second communication being established, one of the first device and the second device being set to a second mode in which an image based on image data transmitted from one of the three or more devices is occupying the display area and displayed, and when the display device receives a request for authorization for a third communication between the third device and the display device from a third device among the three or more devices while displaying the image in the display area, the display device transmits information indicating that authorization for the third communication has been requested to the other device, and the other device The communication control method for a display device according to Supplementary Note 1, further comprising: outputting, to a display unit of the other device, information for allowing a user of the other device to decide whether to approve the authorization for the third communication; when the display device receives from the other device information indicating that the authorization for the third communication has been approved, establishing the third communication; and when the display device is requested to display an image based on image data transmitted from a device other than the device set to the second mode among the three or more devices after the third communication has been established, refusing to allow the display device to display the image based on image data transmitted from the other device. According to Supplementary Note 6, by setting the second mode, it is possible to prevent an image based on image data transmitted from a device other than the device set to the second mode from being projected onto the projection area even if a user of a device other than the device set to the second mode erroneously operates the device.

[0142] (Supplementary Note 7) The plurality of devices are three or more devices, each of the three or more devices having a display unit, the first communication and the second communication being established, both the first device and the second device being set to a first mode in which an image based on image data transmitted from one or more of the three or more devices is displayed on the display device, an image based on the first image data transmitted from the first device is displayed in a first partial area that is a part of the display area, and an image based on the second image data transmitted from the second device is displayed in a second partial area that is a part of the display area and different from the first partial area, and the display device stops updating the image in the first partial area based on the first image data after the first device is set to the third mode when the first device is set to a third mode in which the image to be displayed on the display device is not updated. and when the second device is set to the third mode, the display device stops updating the image of the second partial region based on the second image data after the third mode is set, and when a third device among the three or more devices requests authorization for a third communication between the third device and the display device while the display device is displaying an image in the display region, the display device transmits information indicating that authorization for the third communication has been requested to the device set to the third mode, and the device set to the third mode outputs information to a display unit of the device set to the third mode that prompts a user of the device set to the third mode to decide whether to approve the authorization for the third communication, and when the display device receives information indicating that the authorization for the third communication has been approved from the device set to the third mode, the display device establishes the third communication. According to Supplementary Note 7, by transmitting information to the device set to the third mode that prompts a user of the device set to the third mode to decide whether to approve the authorization for the third communication, communication between the third device and the display device can be established while preventing interference with the display of the image displayed on the display unit of the device set to the first mode.

[0143] (Supplementary Note 8) The communication control method for a display device according to Supplementary Note 2, wherein the display device, in response to receiving from one of the first device and the second device information indicating that the authorization for the third communication has been approved or information indicating that the authorization for the third communication has been denied, transmits information indicating that a decision on whether to approve the authorization for the third communication has been completed to the other of the first device and the second device. According to Supplementary Note 8, since the information indicating that a decision on whether to approve the authorization for the third communication has been completed has been transmitted to the other device, the information displayed on the display unit of the other device for allowing the user of the other device to decide whether to approve the authorization for the third communication can be erased, thereby reducing the operational burden on the user of the other device.

[0144] (Supplementary Note 9) The plurality of devices are three or more devices, each of the three or more devices having a display unit, the first communication and the second communication are established, both the first device and the second device are set to a first mode in which an image based on image data transmitted from one or more of the three or more devices is displayed on the display unit, the image displayed on the display unit of one of the first device and the second device is the same as the image displayed on the display unit of the one device, and the image displayed on the display unit of the other of the first device and the second device is the same as the image displayed on the display unit of the other device. The communication control method for a display device according to Supplementary Note 1, wherein, when the display device receives a request for authorization of a third communication between the third device and the display device from a third device among the three or more devices while displaying an image in the display area that is different from the image displayed on the display area, the display device transmits information indicating that authorization for the third communication has been requested to the other device, and the other device outputs information to a display unit of the other device for prompting a user of the other device to determine whether or not to approve the authorization for the third communication, and the display device establishes the third communication when it receives information indicating that the authorization for the third communication has been approved from the other device. According to Supplementary Note 9, the possibility that the user of one device will feel annoyed can be reduced compared to an aspect in which information for prompting a user of the other device to decide whether or not to approve the authorization for the third communication is sent to one device that causes a display device to display the same image as the image displayed on a display unit.

[0145] (Supplementary Note 10) A display system having a plurality of devices and a display device capable of communicating with the plurality of devices, wherein the display device is capable of displaying an image in a display area, a first communication is established between a first device of the plurality of devices and the display device, and when a second device of the plurality of devices requests authorization for a second communication between the second device and the display device while the display device is displaying an image in the display area, the display device transmits information to the first device indicating that authorization for the second communication has been requested, the first device outputs information to the first device for allowing a user of the first device to decide whether to approve the authorization for the second communication, and when the display device receives information from the first device indicating that authorization for the second communication has been approved, the display device establishes the second communication. Supplementary Note 10 provides the same effect as Supplementary Note 1. [Explanation of symbols]

[0146] 1...display system, 10...projector, 11...processing circuit, 12...memory circuit, 14...communication circuit, 16...input section, 17...display section, 19...bus, 20...projector, 21...processing circuit, 22...memory circuit, 24...communication circuit, 26...input device, 27...projection device, 27a...light source, 27b...display panel, 27c...optical system, 29...bus, CW...communication judgment image, GC, GC_A1, GC_B1, GC_B2, GP, GP_1, GP_A1, GP_A2, GP_B1, GP_B2, GP_i...image, MP...venue, PR...projection area, PR1, PR2...control program, PRJ...projector communication control program, PRM...communication control program, SC...projection surface, SR1, SR2...partial area, STR1...character string, U...presenter, W...audience.

Claims

1. 1. A method for controlling communication with a display device in a display system having a plurality of devices and a display device capable of communicating with the plurality of devices, comprising: the display device capable of displaying an image in a display area establishes a first communication with a first device among the plurality of devices; when a second device among the plurality of devices requests authorization for a second communication between the second device and the display device while the display device is displaying an image in the display area, the display device transmits, to the first device, information indicating that authorization for the second communication has been requested; the first device outputs, to the first device, information for allowing a user of the first device to determine whether or not to approve the authorization for the second communication; When the display device receives information from the first device indicating that authorization for the second communication has been approved, the display device establishes the second communication. A method for controlling communication with a display device.

2. the plurality of devices is three or more devices; each of the three or more devices has a display unit; the first communication and the second communication are established; when a third device among the three or more devices requests authorization for a third communication between the third device and the display device while the display device is displaying an image in the display area, the display device transmits information indicating that authorization for the third communication has been requested to the first device and the second device; the first device outputs information to a display unit of the first device to allow a user of the first device to determine whether or not to approve the authorization of the third communication; the second device outputs, to a display unit of the second device, information for allowing a user of the second device to determine whether or not to approve the authorization of the third communication; When the display device receives information indicating that authorization for the third communication has been approved from at least one of the first device and the second device, the display device establishes the third communication. A method for controlling communication with the display device according to claim 1.

3. the plurality of devices is three or more devices; each of the three or more devices has a display unit; the first communication and the second communication are established; one of the first device and the second device is set to a first mode in which a first image based on image data transmitted from one or more of the three or more devices is displayed on the display device; when a third device among the three or more devices requests authorization for a third communication between the third device and the display device while the display device is displaying the first image in the display area, the display device transmits information indicating that authorization for the third communication has been requested to the other device; the other device outputs, to a display unit of the other device, information for allowing a user of the other device to determine whether or not to approve the authorization of the third communication; When the display device receives information indicating that authorization for the third communication has been approved from the other device, the display device establishes the third communication. A method for controlling communication with the display device according to claim 1.

4. the first image is the same as the image displayed on the display unit of the one device; A method for controlling communication with the display device according to claim 3.

5. the first image is different from the image displayed on the display unit of the one device; A method for controlling communication with the display device according to claim 3.

6. the plurality of devices is three or more devices; each of the three or more devices has a display unit; the first communication and the second communication are established; one of the first device and the second device is set to a second mode in which an image based on image data transmitted from one of the three or more devices is displayed occupying the display area, when a third device among the three or more devices requests authorization for a third communication between the third device and the display device while the display device is displaying an image in the display area, the display device transmits information indicating that authorization for the third communication has been requested to the other devices; the other device outputs, to a display unit of the other device, information for allowing a user of the other device to determine whether or not to approve the authorization of the third communication; When the display device receives information indicating that authorization for the third communication has been approved from the other device, the display device establishes the third communication; when the display device is requested to display an image based on image data transmitted from another device other than the device set to the second mode among the three or more devices after establishing the third communication, the display device refuses to display the image based on the image data transmitted from the other device on the display device. A method for controlling communication with the display device according to claim 1.

7. the plurality of devices is three or more devices; each of the three or more devices has a display unit; the first communication and the second communication are established; both the first device and the second device are set to a first mode in which an image based on image data transmitted from one or more of the three or more devices is displayed on the display device; an image based on first image data transmitted from the first device is displayed in a first partial area that is a part of the display area; an image based on second image data transmitted from the second device is displayed in a second partial area that is a part of the display area and is different from the first partial area; the display device stops updating the image of the first partial region based on the first image data after the display device is set to the third mode when the first device is set to a third mode in which the image displayed on the display device is not updated, and stops updating the image of the second partial region based on the second image data after the display device is set to the third mode when the second device is set to the third mode; when a third device among the three or more devices requests authorization for a third communication between the third device and the display device while the display device is displaying an image in the display area, the display device transmits information indicating that authorization for the third communication has been requested to the device set to the third mode; the device set to the third mode outputs information to a display unit of the device set to the third mode to allow a user of the device set to the third mode to determine whether or not to approve the authorization of the third communication; When the display device receives information indicating that authorization for the third communication has been approved from the device set to the third mode, the display device establishes the third communication. A method for controlling communication with the display device according to claim 1.

8. In response to receiving, from one of the first device and the second device, information indicating that authorization for the third communication has been approved or information indicating that authorization for the third communication has been denied, the display device transmits, to the other of the first device and the second device, information indicating that a decision on whether to approve authorization for the third communication has been completed. A method for controlling communication with the display device according to claim 2.

9. the plurality of devices is three or more devices; each of the three or more devices has a display unit; the first communication and the second communication are established; both the first device and the second device are set to a first mode in which an image based on image data transmitted from one or more of the three or more devices is displayed on the display device; an image that one of the first device and the second device causes to be displayed on the display device is the same as an image displayed on a display unit of the one of the first device and the second device; an image displayed on the display device of the other of the first device and the second device is different from an image displayed on a display unit of the other device; when a third device among the three or more devices requests authorization for a third communication between the third device and the display device while the display device is displaying an image in the display area, the display device transmits information indicating that authorization for the third communication has been requested to the other device; the other device outputs, to a display unit of the other device, information for allowing a user of the other device to determine whether or not to approve the authorization of the third communication; When the display device receives information indicating that authorization for the third communication has been approved from the other device, the display device establishes the third communication. A method for controlling communication with the display device according to claim 1.

10. A display system having a plurality of devices and a display device capable of communicating with the plurality of devices, the display device is capable of displaying an image in a display area; a first communication is established between a first device of the plurality of devices and the display device; when a second device among the plurality of devices requests authorization for a second communication between the second device and the display device while the display device is displaying an image in the display area, the display device transmits, to the first device, information indicating that authorization for the second communication has been requested; the first device outputs, to the first device, information for allowing a user of the first device to determine whether or not to approve the authorization for the second communication; When the display device receives information from the first device indicating that authorization for the second communication has been approved, the display device establishes the second communication. Display system.

Images