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 three or more devices and a display device. The display device establishes first communication with a first device in which management authority for managing authorization of communication with the display device is set, and second communication with a second device. When a third device requests authorization of third communication with the display device while the image is displayed in a display region, the display device transmits, to a management device in which the management authority is set, information indicating that the authorization of the third communication is requested, the management device outputs, to the management device, communication determination information for causing a user of the management device to determine whether to approve the authorization of the third communication, and the display device establishes the third communication when information indicating that the authorization of the third communication was approved is received from the management 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 three or more 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 interrupted. [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 three or more devices and a display device capable of communicating with the three or more devices, wherein the display device capable of displaying an image in a display area establishes a first communication with a first device among the three or more devices that has been set with administrative authority to manage authorization for communication with the display device, and a second communication with a second device among the three or more devices, 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 an image in the display area, the display device transmits authorization request information indicating that authorization for the third communication has been requested to an administrative device that is a device set with the administrative authority, and when the administrative device receives the authorization request information, the administrative device outputs communication judgment information to the administrative device to allow a user of the administrative device to decide whether to approve the authorization for the third communication, and when the display device receives approval information from the administrative device indicating that the authorization for the third communication has been approved, the display device establishes the third communication.

[0006] A display system according to one embodiment of the present disclosure is a display system having three or more devices and a display device capable of communicating with the three or more devices, wherein the display device is capable of displaying an image in a display area, a first communication between a first device of the three or more devices and the display device, and a second communication between a second device of the three or more devices and the display device are established, and administrative authority for managing connections to the display device is set in the first device, 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 of the three or more devices while displaying an image in the display area, the display device transmits authorization request information indicating that authorization for the third communication has been requested to an administrative device which is the device set as the administrative authority, and when the administrative device receives the authorization request information, the administrative device outputs communication judgment information to the administrative device to allow a user of the first device to decide whether to approve the authorization for the third communication, and when the display device receives approval information from the administrative device indicating that the authorization for the third communication has been approved, the display device establishes the third 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. 11 is a flowchart showing an example of a process performed when a communication request is received in the second embodiment. [Figure 9] FIG. 10 is a flowchart showing an example of an authorization request information transmission process. [Figure 10] FIG. 10 is a flowchart showing an example of the operation of the projector 20 in the first modified example. [Figure 11] FIG. 10 is a flowchart showing an example of an administrative authority PC resetting process. [Figure 12] FIG. 10 is a diagram showing an example of a selection indicator image DW. [Figure 13] FIG. 10 is a flowchart showing an example of the operation of the projector 20 in the second modified example. [Figure 14] FIG. 11 is a flowchart showing an example of management authority PC resetting processing in a second modified example. [Figure 15] FIG. 10 is a diagram showing an example of a selection indicator image DWB. [Figure 16] FIG. 10 is a flowchart showing an example of processing when image data is received. [Figure 17] FIG. 11 is a flowchart showing an example of the operation of the projector 20 in a third modified example. [Figure 18] FIG. 10 is a flowchart showing an example of the operation of an occupation mode release process. 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 displayed in 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 N (three or more) 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. In this embodiment, for simplicity, the presenter U_i who operates the PC 10_i will explain the image GC displayed in the projection area PR. However, the person who operates the PC 10_i and the person who explains the image GC may be different people. The N PCs 10 are an example of "three or more 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 three or more 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] There are, for example, the following two situations in which the display system 1 is applicable. In the first situation in which the display system 1 is applicable, the event is a meeting, and the first presenter U_1 is the organizer of the meeting and gives an overall explanation of the meeting. The second and subsequent presenters U give explanations based on their respective agendas. In the second situation in which the display system 1 is applicable, the event is a class, and the first presenter U_1 is the homeroom teacher in charge of the class, and the second and subsequent presenters U are students taking the class. The teacher, who is presenter U_1, explains the content of the assignment given to the students in the previous class. The students, who are presenters U from now on, explain their answers to the assignment.

[0014] The configurations of the PC 10 and the projector 20 will be described with reference to FIGS.

[0015] 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.

[0016] The processing circuit 11 is a computer such as a CPU, etc. The processing circuit 11 may be configured by one or more processors.

[0017] 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.

[0018] 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.

[0019] 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.

[0020] 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 ElectroLuminescence. The input unit 16 and the display unit 17 may be integrated into one unit. The input unit 16 and the display unit 17 integrated into one unit is, for example, a touch panel.

[0021] 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.

[0022] 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.

[0023] The processing circuit 21 is a computer such as a CPU, etc. The processing circuit 21 may be configured by one or more processors.

[0024] 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.

[0025] 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.

[0026] 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.

[0027] 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.

[0028] 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.

[0029] 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.

[0030] 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.

[0031] 1-2. Regarding the progress of the event During the event, a connection between PC10_1 and the projector 20 and a connection between PC10_2 and the projector 20 are established. While presenter U_1 or presenter U_2 is explaining an image GC, presenter U_3, who is to present after presenter U_2, requests to proceed with preparations for projection on the projector 20. An example of preparations for projection is establishing a connection between PC10_3 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 a service that allows the projector 20 to project an image. Alternatively, establishing a connection may involve performing a three-way handshake when TCP is used for communication between PC10 and the 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 the PC 10 and the projector 20 may be described as "the PC 10 logging in to the projector 20."

[0032] Generally, the time available for presenter U to give his / her presentation is allocated in advance. If a problem occurs in which PC 10_3 cannot log in to the projector 20, and it takes time to resolve this problem, the time available for presenter U_3 to give his / her presentation may be shortened. Therefore, by having PC 10_3 log in to the projector 20 while presenter U_1 or presenter U_2 is giving a presentation on the image GC, presenter U_3 can smoothly continue his / her presentation after presenter U_2 has finished his / her presentation.

[0033] 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.

[0034] A situation may arise in which PC10_3 requests permission from the projector 20 to connect to the projector 20 while presenter U_1 or presenter U_2 is explaining the image GP in order for PC10_3 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 or PC10_2 may be obstructed. If the display of the image GP based on the image data transmitted from PC10_1 or PC10_2 is obstructed, presenter U_1 or presenter U_2 may be unable to continue with their explanation of the image GP. Furthermore, presenter U_1 or presenter U_2 must explain to audience W that the image including the identification code is unrelated to the content of the explanation given by presenter U_1 or presenter U_2.

[0035] Therefore, in the display system 1 of this embodiment, management authority for managing authorization of communication with the projector 20 is set to PC 10_1. Then, when PC 10_3 requests authorization for communication between PC 10_3 and the projector 20, the request for authorization for this communication is notified to PC 10_1, to which management authority has been set. In the following description, the request for authorization for communication may be referred to as a "communication request." PC 10_1 outputs information for allowing presenter U_1 to determine whether to approve the authorization for this communication to the display unit 17 of PC 10_1. The information for allowing presenter U_1 to determine whether to approve the authorization for communication between PC 10_3 and the projector 20 may be a character string indicating whether to approve the authorization for communication between PC 10_3 and the projector 20, or may be image data indicating an image. In the following description, the information for allowing presenter U_1 to determine whether to approve the authorization for communication between PC 10_3 and the projector 20 is assumed to be image data, and may be referred to as "communication determination image data." When the projector 20 receives from the PC 10_1 information indicating that the authorization for communication between the PC 10_3 and the projector 20 has been approved, the PC 10_3 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.

[0036] 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 description will be made 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 PC10_1, which is the first to log in to the projector 20. Then, the projector 20 prompts 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." Of the three or more PCs 10 included in the display system 1, there is only one management authority PC10_m. The management authority PC10_m is an example of a "management device."

[0037] 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".

[0038] 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.

[0039] 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.

[0040] 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.

[0041] 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.

[0042] 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.

[0043] 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.

[0044] 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.

[0045] 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.

[0046] 4 and 5. After the process of step SP8 is completed, the processing circuit 21 executes the process of step SP4 again.

[0047] 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.

[0048] 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.

[0049] 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.

[0050] 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.

[0051] 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.

[0052] 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.

[0053] 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.

[0054] 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 the 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 is 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.

[0055] 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.

[0056] 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.

[0057] 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.

[0058] 4 and 6. 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 the administrative authority PC 10_m, as shown in FIG. 6. If the determination result of 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 the button BTN1 is pressed by the presenter U_1 on the 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 of step SP44 is positive.

[0059] If the determination result of step SP44 is positive, 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 grants login permission to the PC 10 that sent the communication request in step SP52, and the PC 10 that sent the communication request logs in to the projector 20. The processing of step SP52 is the same as the processing of step SP38. In the example of FIG. 4, the processing circuit 21 grants login permission to PC 10_2. After completing the processing of step SP52, the processing circuit 21 ends the series of processes shown in FIG. 6.

[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 communication determination information to the administrative authority PC 10_m, PC 10_1 in the example of FIG. 4. In step SC14, the PC 10_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 the PC 10_3 and the projector 20.

[0063] 4, the description will be given on the assumption that the processing circuit 11_1 of PC10_1 transmits approval information to the projector 20 in step SC18 based on the operation of the presenter U_1. When the projector 20 receives the approval information, the processing circuit 21 grants login permission to PC10_3, which is the PC 10 that transmitted the communication request, in step SP52, as shown in FIG.

[0064] 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.

[0065] The display system 1 in the first embodiment is a display system 1 having three or more PCs 10 and a projector 20 capable of communicating with the three or more PCs 10. Furthermore, the display system 1 executes a communication control method for the projector 20. The projector 20 capable of projecting an image into the projection area PR establishes, in step SP38, first communication with PC 10_1, of the three or more PCs 10, which has been set with administrative authority to manage authorization for communication with the projector 20, and in step SP52 establishes second communication with PC 10_2, of the three or more PCs 10. If authorization for third communication is requested by PC 10_3, of the three or more PCs 10, while the projector 20 is projecting an image into the projection area PR, the projector 20 transmits, in step SP42, communication determination information indicating that authorization for the third communication has been requested to the administrative authority PC 10_m, which is the PC 10 set with administrative authority. The management authority PC 10_m outputs communication determination image data, which is information for allowing the user of the management authority PC 10_m to determine whether or not to approve the authorization for the third communication, to the display unit 17_1 of the management authority PC 10_m. The display unit 17_1 is an example of an output destination of information for allowing the presenter U_1 to determine whether or not to approve the authorization for the third communication. When the projector 20 receives approval information indicating that the authorization for the third communication has been approved from the management authority PC 10_m, it establishes the third 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 PC10_1 is not hindered. Furthermore, PC10_3 can establish communication with the projector 20. Therefore, according to the first embodiment, PC10_3 can establish communication with the projector 20 while suppressing the hinderance of the display of the image based on the image data transmitted from PC10_1 or PC10_2.

[0066] 2. Second embodiment The second embodiment differs from the first embodiment in that, if there is no response from the administrative authority PC 10_m, the administrative authority is transferred to another PC 10. The second embodiment will be described below.

[0067] 2-1. Operation of the second embodiment Fig. 8 is a flowchart showing an example of processing when a communication request is received in the second embodiment. Compared to the flowchart shown in Fig. 6, the flowchart shown in Fig. 8 differs from the flowchart shown in Fig. 6 in that the processing of step SP42 and the processing of step SP44 are replaced by the processing of step SP62, the processing of step SP62 is executed after the processing of step SP38, the processing of step SP64 is executed after the processing of step SP38, and the processing of step SP66 is executed after the processing of step SP52, but the other parts are the same. Hereinafter, only the differences from the flowchart shown in Fig. 8 will be described.

[0068] After completing the process of step SP38, the processing circuit 21 records, in step SP64, time information indicating the time when the PC 10 that logged in in step SP38 logged in to the storage circuit 22. The time information is, for example, a character string indicating the time. Specifically, in step SP64, the processing circuit 21 records, in the storage circuit 22, time information indicating the current time as time information indicating the time when the PC 10 logged in, in association with the identification information of the PC 10 that logged in in step SP38. The identification information of the PC 10 is, for example, one or more of the name of the PC 10, the serial number of the PC 10, the MAC address of the PC 10, and the IP address of the PC 10. MAC is an abbreviation for Media Access Control. IP is an abbreviation for Internet Protocol. After completing the process of step SP64, the processing circuit 21 executes the process of step SP40.

[0069] After the process of step SP52 is completed, in step SP66 the processing circuit 21 records the time when the PC 10 that logged in in step SP52 logged in to the storage circuit 22. The process of step SP66 is the same as the process of step SP64.

[0070] If the determination result in step SP32 is positive, the processing circuit 21 executes an authorization request information transmission process in step SP62. The authorization request information transmission process will be described with reference to FIG.

[0071] Fig. 9 is a flowchart showing an example of authorization request information transmission processing. In the flowchart shown in Fig. 9, the processing of step SP42 and the processing of step SP44 are the same as the processing of step SP42 and step SP44 in the flowchart shown in Fig. 6, respectively, and therefore a description of the processing will be omitted. Note that, hereinafter, if the step number is the same as the step number already explained, the description will be omitted assuming that it has already been explained.

[0072] The processing circuit 21 executes the process of step SP42 and then executes the process of step SP44. If the determination result of step SP44 is positive, the processing circuit 21 ends the series of processes shown in FIG.

[0073] If the determination result in step SP44 is negative, the processing circuit 21 determines in step SP72 whether a predetermined period of time has elapsed since the authorization request information was transmitted. The predetermined period of time may be any length. For example, the predetermined period of time is one minute. If the determination result in step SP72 is negative, the processing circuit 21 executes the processing of step SP44 again.

[0074] If the determination result in step SP72 is positive, in step SP74, the processing circuit 21 sets the PC 10 that logged in earliest, among the one or more PCs 10 that have logged in to the projector 20, as the administrative authority PC10_m. For example, if the number of PCs 10 that have logged in to the projector 20 is two, and one of the PCs 10 is the administrative authority PC10_m, the processing circuit 21 sets the other PC 10 as the administrative authority PC10_m. Also, in step SP74, the processing circuit 21 may set the PC 10 that logged in earliest, among the one or more PCs 10 that have logged in to the projector 20, excluding the PC 10 that has disconnected communication with the projector 20, as the administrative authority PC10_m. The PC 10 that has disconnected communication with the projector 20 is, in other words, the PC 10 that has logged out from the projector 20. For example, the processing circuit 21 deletes the time information associated with the identification information of the PC 10 that has logged out from the storage circuit 22.

[0075] After the process of step SP74 is completed, the processing circuit 21 executes the process of step SP42. Therefore, the projector 20 switches the administrative authority PC10_m every time a predetermined period of time elapses. Furthermore, after the process of step SP74 is completed, the processing circuit 21 may instruct the PC 10 set as the administrative authority PC10_m to display a dialog box indicating "Administrative authority has been set."

[0076] 2-2. Summary of the second 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. Furthermore, a summary of the second embodiment will be described using a state in which the PCs 10 logged in to the projector 20 are PC10_1 and PC10_2, and PC10_1 is set as the administrative authority PC10_m.

[0077] If a predetermined period of time has passed since the projector 20 transmitted the authorization request information to the PC 10_1 having the administrative authority PC 10_m without the projector 20 receiving approval information or denial information, the projector 20 sets the administrative authority to the PC 10_2. According to the second embodiment, if the presenter U_1 of PC10_1 misses the communication judgment image CW, or if the presenter U_1 is busy for reasons such as being on a call on his / her mobile phone and is unable to operate PC10_1, another presenter U can temporarily decide whether to approve the authorization for communication between PC10_3 and projector 20.

[0078] 3. 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.

[0079] 3-1. First modified example The first modified example differs from the second embodiment in that, when the projector 20 receives a logout instruction from the administrative authority PC 10_m, the presenter U of the administrative authority PC 10_m selects the next administrative authority PC 10_m from one or more PCs 10 currently logged in to the projector 20. The first modified example will be described below.

[0080] 3-1-1. Operation of the first modified example Fig. 10 is a flowchart showing an example of the operation of projector 20 in the first modified example. The flowchart shown in Fig. 10 differs from the flowchart shown in Fig. 5 in that if the determination result in step SP14 is negative, the process of step SP82 is executed, but the other parts are the same. Hereinafter, only the differences from the flowchart shown in Fig. 5 will be explained.

[0081] If the determination result of step SP14 is negative, the processing circuit 21 determines in step SP82 whether or not a logout instruction has been received from the administrative authority PC 10_m. If the determination result of step SP82 is negative, the processing circuit 21 executes the processing of step SP4 again. If the determination result of step SP82 is positive, the processing circuit 21 executes administrative authority PC resetting processing in step SP84. The administrative authority PC resetting processing will be described with reference to FIG. 11.

[0082] 11 is a flowchart showing an example of management authority PC resetting processing. The management authority PC resetting processing is processing for setting the next management authority PC 10_m from a PC 10 other than the management authority PC 10_m among one or more PCs 10 currently logged in to the projector 20, based on the operation result of the input unit 16 of the presenter U of the management authority PC 10_m before the management authority PC 10_m logs out from the projector 20.

[0083] In step SP92, the communication circuit 24 transmits an instruction to select the next management authority PC 10_m to the management authority PC 10_m under the instruction of the processing circuit 21. The selection instruction includes a list of the identification information of the PC 10 stored in the memory circuit 22 by executing the processing of steps SP64 and SP66.

[0084] When a selection instruction is received, the management authority PC 10_m generates image data showing a selection instruction image DW based on the selection instruction, and displays the selection instruction image DW on the display unit 17. The selection instruction image DW will be described with reference to FIG.

[0085] Fig. 12 is a diagram showing an example of a selection instruction image DW. In the example of Fig. 12, it is assumed that the one or more PCs 10 currently logged in to the projector 20 are PC10_1, PC10_2, and PC10_3, and that the administrative authority PC10_m is PC10_1.

[0086] In the example of FIG. 12, the selection instruction image DW has a character string STR2, a radio button group RG1, a button BTN3, and a button BTN4. The character string STR2 is "Do you want to transfer administrative authority?" The radio button group RG1 has a radio button RD associated with the identification information of PC10 included in the selection instruction. Therefore, the radio button group RG1 shown in FIG. 12 has a radio button RD1 associated with the identification information of PC10_2 and a radio button RD2 associated with the identification information of PC10_3. When one of the radio buttons RD1 and RD2 is selected, the selection of the other radio button is deselected.

[0087] Button BTN3 is a button for canceling logout. The text "Cancel logout" is displayed on button BTN3. Button BTN4 is a button for selecting the PC 10 indicated by the radio button RD selected by the administrative authority PC 10_m, out of radio buttons RD1 and RD2, as the next administrative authority PC 10_m and logging out. Button BTN4 is a button for selecting the PC 10 indicated by the radio button RD selected by the administrative authority PC 10_m, out of radio buttons RD1 and RD2, as the next administrative authority PC 10_m and logging out.

[0088] When button BTN3 is pressed, the management authority PC 10_m transmits cancel instruction information indicating an instruction to cancel logout to the projector 20. When button BTN4 is pressed, the management authority PC 10_m transmits to the projector 20 the identification information of the PC 10 associated with the radio button RD selected by the presenter U of the management authority PC 10_m. The PC 10 indicated by the identification information transmitted to the projector 20 is the PC 10 identified based on the result of operation of the input unit 16 of the PC 10 by the presenter U of the management authority PC 10_m while logged in to the projector 20.

[0089] Returning to Fig. 11 for the explanation, after the processing of step SP92 is completed, the processing circuit 21 determines in step SP94 whether or not it has received identification information of the PC 10 from the projector 20. If the determination result in step SP94 is negative, the processing circuit 21 determines in step SP96 whether or not it has received instruction information to cancel logout. If the determination result in step SP96 is negative, the processing circuit 21 executes the processing of step SP94 again.

[0090] If the determination result of step SP94 is positive, then in step SP98 the processing circuit 21 sets the administrative authority PC10_m to the PC10 indicated by the received identification information. After completing the processing of step SP98, the processing circuit 21 logs out the PC10 that was set as the administrative authority PC10_m in step SP100. After completing the processing of step SP100, the processing circuit 21 ends the series of processes shown in FIG. 11. If the determination result of step SP96 is positive, then the processing circuit 21 also ends the series of processes shown in FIG. 11. As can be seen from FIG. 11, if the determination result of step SP96 is positive, the processing circuit 21 does not execute step SP100, and therefore the logout of the administrative authority PC10_m is canceled.

[0091] In the flowchart shown in FIG. 11 , the projector 20 sets the next administrative authority PC 10_m based on the operation result of the input unit 16 of the presenter U of the administrative authority PC 10_m in steps SP92, SP94, and SP96. However, the method for setting the next administrative authority PC 10_m is not limited to this. For example, the projector 20 may set the PC 10 with the strongest received signal received by the communication circuit 24 from a PC 10 other than the administrative authority PC 10_m among one or more PCs 10 currently logged in to the projector 20 as the next administrative authority PC 10_m. Alternatively, as in the second embodiment, the projector 20 may set the PC 10 with the earliest login time to the projector 20 from a PC 10 other than the administrative authority PC 10_m among one or more PCs 10 currently logged in to the projector 20 as the next administrative authority PC 10_m. Note that in an aspect in which the next administrative authority PC 10_m is set based on the strength of the received signal, the projector 20 and each of the N PCs 10 need to be directly connected by wireless communication without using a relay device.

[0092] Furthermore, the aspect of setting the next administrative authority PC10_m based on the strength of the received signal and the aspect of setting the next administrative authority PC10_m based on the time of login to the projector 20 can also be applied to the second embodiment. Specifically, when the determination result in step SP72 of Fig. 9 is positive, the processing circuit 21 may set the PC 10 with the strongest received signal received by the communication circuit 24 as the administrative authority PC10_m instead of the processing of step SP74. Alternatively, when the determination result in step SP72 of Fig. 9 is positive, the processing circuit 21 may set the PC 10 with the earliest login time to the projector 20 as the administrative authority PC10_m instead of the processing of step SP74.

[0093] 3-1-2. Summary of the first 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, and communication between PC10_3 and the projector 20 will be referred to as third communication, and a summary of the first modified example will be explained.

[0094] In a state where the first communication and the second communication are established, when the projector 20 receives an instruction to disconnect the first communication from the management authority PC10_m which is the PC10_1, the projector 20 sets the management authority to the PC10_2. "When the projector 20 receives an instruction to disconnect the first communication from the management authority PC10_m" is an example of "in response to the first communication being disconnected." According to the first variant, when communication with PC10_1, which has been granted administrative authority, is disconnected and another PC10 requests connection to the projector 20, the presenter U_2 of PC10_2 can decide whether to approve the authorization for communication between PC10_3 and the projector 20.

[0095] The three or more PCs 10 refer to four or more PCs 10, each of which has an input unit 16, and in addition to the first and second communications being established, a fourth communication is established between PC10_4 of the four or more PCs 10 and the projector 20. PC10_4 is an example of a "fourth device." When the projector 20 receives an instruction to disconnect the first communication from PC10_1, it sets administrative authority to one of PC10_2 and PC10_4, which is identified based on the result of an operation of the input unit 16 of PC10_1 by presenter U_1 of PC10_1 while the first communication was established. For example, the projector 20 sets administrative authority to PC10_2. According to the first modification, when another PC 10 requests connection to the projector 20 after communication with PC 10_1, which has been set with administrative authority, is disconnected, the presenter U of PC 10_4, which has been set with administrative authority, can determine whether to approve the permission for communication between PC 10_3 and the projector 20. Furthermore, among the N presenters U, the presenter U of PC 10, which has been set with administrative authority PC 10_1, is likely to be the most familiar with operating the administrative authority of the projector 20. For example, the organizer, who is the presenter U_1 in the first situation in which the display system 1 is applied, and the teacher, who is the presenter U_1 in the second situation in which the display system 1 is applied, are likely to be the most familiar with operating the administrative authority of the projector 20 among the N presenters. Therefore, in an aspect in which the administrative authority PC10_m is set based on the operation result of the input unit 16 of PC 10_1, the administrative authority can be set to the PC 10 of the presenter U, who is recognized by the presenter U_1, who is likely to be the most familiar with operating the administrative authority of the projector 20.

[0096] Furthermore, the three or more PCs 10 refer to four or more PCs 10, each of which can communicate with the projector 20 via wireless communication, and in addition to the first and second communications being established, a fourth communication is established between PC10_4 of the four or more PCs 10 and the projector 20. If a predetermined period of time has passed since the projector 20 transmitted authorization request information to PC10_1 without the projector 20 receiving either approval information or denial information, or if the projector 20 receives an instruction from PC10_1 to disconnect the first communication, the projector 20 may set the administrative authority to the PC 10 between PC10_2 and PC10_4 which has a stronger wireless signal strength or which established communication with the projector 20 earlier. According to the first modification, if the presenter U_1 of PC10_1 misses the communication determination image CW, or if the presenter U_1 is busy and cannot operate PC10_1, the presenter U of PC10_2 or PC10_4 can temporarily determine whether to approve the authorization for communication between PC10_3 and the projector 20. Furthermore, among the N presenters U, the presenter U closest to the projector 20 is likely to be familiar with operating the projector 20, for example, by directly operating the projector 20, and is therefore likely to be familiar with operating the administrative authority of the projector 20. Therefore, in an aspect in which the PC 10 with the strongest received signal of the wireless connection is set as the administrative authority PC10_m, the administrative authority can be set to the PC 10 of the presenter U who is likely to be familiar with operating the administrative authority of the projector 20. Furthermore, among the N presenters U, the presenter U of the PC 10 who logged in to the projector 20 earlier may be preparing for the event together with the presenter U_1. Therefore, the presenter U of the PC 10 who logged in to the projector 20 earlier may be familiar with operating the projector 20 and may also be familiar with operating the administrative authority of the projector 20. Therefore, in an aspect in which the PC 10 who logged in to the projector 20 earlier is set as the administrative authority PC10_m, administrative authority can be set to the PC 10 of the presenter U who may be familiar with operating the administrative authority of the projector 20. Furthermore, in an aspect in which the administrative authority PC10_m is set based on the operation result of the input unit 16 of the PC 10_1, even if the presenter U_1 needs to move to the next event, the presenter U_1 must select the next administrative authority PC10_m, which is time-consuming. On the other hand, in an aspect in which the PC 10 with the strongest received signal of the wireless connection is set as the administrative authority PC10_m and an aspect in which the PC 10 who logged in to the projector 20 earlier is set as the administrative authority PC10_m, the presenter U_1's time and effort can be reduced.

[0097] 3-2. Second modified example The second modified example differs from the first embodiment, the second embodiment, and the first modified example in that, when a PC 10 that has logged in to the projector 20 is in a mode in which the projector 20 occupies the projection area PR and displays an image, a PC 10 that has newly logged in to the projector 20 will refuse to allow the projector 20 to display an image. The second modified example will be described below.

[0098] 3-2-1. Operation of the second modified example Fig. 13 is a flowchart showing an example of the operation of projector 20 in the second modified example. Compared to the flowchart shown in Fig. 5, the flowchart shown in Fig. 13 executes the process of step SP10B instead of the process of step SP10, and differs from the flowchart shown in Fig. 5 in the series of processes when the determination result of step SP10B is positive, but the other parts are the same. Hereinafter, only the differences from the flowchart shown in Fig. 5 will be described.

[0099] If the determination result of step SP6 is negative, the processing circuit 21 determines in step SP10B whether reception of image data has started or whether a transition to exclusive mode has been instructed by the presenter U of the PC 10. The 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 the display system 1 is displayed in the projection area PR. In the following description, a PC 10 in which the exclusive mode is set may be referred to as the "occupied PC 10_o." The display unit 17 of the occupied PC 10_o may be referred to as the "display unit 17_o." The presenter U of the occupied PC 10_o may be referred to as the presenter U_o. The exclusive mode is an example of a "first mode." An instruction to transition to exclusive mode is, for example, pressing a "transition to exclusive mode" button displayed on the display unit 17 of the PC 10.

[0100] If the determination result of step SP10B is negative, the processing circuit 21 executes the processing of step SP14. If the determination result of step SP10B is positive, the processing circuit 21 determines in step SP18 whether or not an instruction to transition to exclusive mode has been issued from the management authority PC 10_m. If the determination result of step SP18 is positive, the processing circuit 21 executes management authority PC resetting processing in the second modified example in step SP84B. The management authority PC resetting processing in the second modified example will be described with reference to FIG. 14.

[0101] Fig. 14 is a flowchart showing an example of administrative authority PC resetting processing in the second modified example. The flowchart shown in Fig. 14 differs from the flowchart shown in Fig. 11 in that step SP96B is executed instead of step SP96, and Fig. 14 ends after step SP98 is executed without executing step SP100, but the other parts are the same. Hereinafter, only the differences from the flowchart shown in Fig. 11 will be explained.

[0102] When the management authority PC10_m receives a selection instruction through the processing of step SP92, it generates image data showing a selection instruction image DWB in the second modified example based on the selection instruction, and displays the selection instruction image DWB on the display unit 17. The selection instruction image DWB will be described with reference to FIG. 15 .

[0103] Fig. 15 is a diagram showing an example of a selection instruction image DWB. In the example of Fig. 15, it is assumed that the one or more PCs 10 currently logged in to the projector 20 are PC10_1, PC10_2, and PC10_3, and that the administrative authority PC10_m is PC10_1.

[0104] In the example of Fig. 15, the selection indicator image DWB has a character string STR2, a radio button group RG1, a button BTN5, and a button BTN6. Only the differences from Fig. 12 will be explained below.

[0105] Button BTN5 is a button that switches to exclusive mode without transferring administrative rights. Button BTN5 displays the text "Switch to exclusive mode without transferring administrative rights." Button BTN6 is a button that switches to exclusive mode after transferring administrative rights. Button BTN6 displays the text "Switch to exclusive mode after transferring administrative rights."

[0106] When button BTN5 is pressed, the management authority PC 10_m transmits exclusive mode transition instruction information without transferring management authority, which indicates an instruction to transition to exclusive mode without transferring management authority, to the projector 20. When button BTN6 is pressed, the management authority PC 10_m transmits to the projector 20 the identification information of the PC 10 associated with the radio button RD selected by the presenter U of the management authority PC 10_m.

[0107] If the determination result in step SP94 is negative, the processing circuit 21 determines in step SP96 whether or not information instructing transition to the exclusive mode without transfer of administrative authority has been received. If the determination result in step SP96 is negative, the processing circuit 21 executes the processing of step SP94 again.

[0108] The description will return to Fig. 13. After the process of step SP84B is completed, or if the determination result of step SP18 is negative, the processing circuit 21 executes the image data reception process in step SP22. The image data reception process will be described with reference to Fig. 16.

[0109] 16 is a flowchart showing an example of the image data reception process. In step SP122, the processing circuit 21 determines whether there is a PC 10 in which the exclusive mode has been set.

[0110] If the determination result in step SP122 is negative, the processing circuit 21 determines in step SP124 whether or not the presenter U of the PC 10 that sent the image data has instructed the projection device 27 to switch to exclusive mode. If the determination result in step SP124 is negative, the projection device 27 executes the processing of step SP12. After completing the processing of step SP12, the processing circuit 21 ends the series of processing shown in FIG. 16.

[0111] If the determination result in step SP124 is positive, the processing circuit 21 sets the PC 10 instructed to transition to the exclusive mode to the exclusive mode in step SP126. Next, in step SP128, 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 is 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 exclusive PC 10_o. In the following description, the image that the exclusive PC 10_o causes the projector 20 to display may be referred to as an "occupied image." After completing the processing in step SP128, the processing circuit 21 ends the series of processes shown in FIG. 16.

[0112] There are two modes of the occupied image as follows. In the first mode, the occupied image is the same as the image displayed on the display unit 17_o of the occupied PC 10_o. Hereinafter, the occupied image in the first mode may be referred to as a "mirrored image."

[0113] The occupied image in the second mode is different from the image displayed on display unit 17_o. Specifically, the occupied image in the second mode is an image that is a portion of the image displayed on display unit 17_o. The image that is a portion of the image displayed on display unit 17_o is, for example, an enlarged image of a portion of the image displayed on display unit 17_o, or an image in a window of an application program displayed on display unit 17_o. Any type of application program may be used, for example, a program for creating documents and a program for displaying documents. Hereinafter, the occupied image in the second mode may be referred to as a "partially occupied image."

[0114] If the determination result in step SP122 is positive, in step SP130, 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 in step SP130, the processing circuit 21 ends the series of processes shown in FIG.

[0115] The explanation returns to Fig. 13. After completing the processing of step SP22, the processing circuit 21 ends the processing of step SP4. The communication request reception processing executed in step SP8 remains unchanged from the first embodiment. In the processing of step SP42 in the communication request reception processing, the communication circuit 24 transmits authorization request information to the management authority PC10_m set in the processing of step SP96.

[0116] 3-2-2. 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 is set as administrative authority PC10_m.

[0117] In the display system 1 in the first variant, each of three or more PCs 10 has a display unit 17, a projector 20 establishes first communication, second communication, and third communication, and when PC10_1 is set to occupancy mode, the projector 20 sets management authority to PC10_2, and when PC10_3 requests that the projector 20 project an image into the projection area PR while the projector 20 is projecting an image into the projection area PR, the projector 20 refuses to allow the projector 20 to display an image based on image data sent from PC10_3. According to the first modification, the display unit 17 of the PC 10_2 not in the exclusive mode displays the communication determination image CW indicated by the communication determination image data, thereby not bothering the presenter U_1 of the PC 10_1 in the exclusive mode.

[0118] The mirrored image, which is the occupied image in the first mode, is the same as the image displayed on the display unit 17_o of the occupied PC 10_o. Since the presenter U_o of the occupied PC 10_o may give a presentation while looking at the image displayed on the display unit 17_o, if the communication determination image CW were to be displayed on the display unit 17_o, the presenter U_o might feel annoyed because the presentation related to the image displayed on the display unit 17_o would be interrupted. Therefore, according to the second 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_o from feeling annoyed.

[0119] The partial shared image, which is the shared image in the second mode, is different from the image displayed on the display unit 17_o of the occupied PC 10_o. The display unit 17_o may display a related image related to the image projected by the projector 20. This related image may be, for example, one or both of an image showing a manuscript that the presenter U_o will read out for explanation purposes and an image showing a timer for keeping the presenter U_o within the allotted time. If the communication determination image CW were to be displayed on the display unit 17_o, the related image would be hidden by the communication determination image CW, which may be bothersome to the presenter U_o. According to the second modification, the communication determination image CW can be prevented from being superimposed on the related image, thereby preventing the presenter U_o from feeling bothered.

[0120] 3-3.Third Modification The third modification differs from the second modification in that when the PC 10 set as the administrative authority PC 10_m shifts to the exclusive mode and is no longer the administrative authority PC 10_m, and then the exclusive mode is released, the PC 10 is set as the administrative authority PC 10_m again. The third modification will be described below.

[0121] 3-3-1. Operation of the third modified example Fig. 17 is a flowchart showing an example of the operation of projector 20 in the third modified example. Compared to the flowchart shown in Fig. 13, the flowchart shown in Fig. 17 differs from the flowchart shown in Fig. 13 in that the process of step SP24 is executed when the determination result of step SP10B is negative, and the process of step SP26 is executed when the determination result of step SP24 is positive, but the other parts are the same. Hereinafter, only the differences from the flowchart shown in Fig. 13 will be described.

[0122] If the determination result in step SP10B is negative, in step SP24, the processing circuit 21 determines whether or not an instruction to cancel the exclusive mode has been given by the presenter U of the PC 10. The instruction to cancel the exclusive mode is, for example, given by pressing a "Cancel Exclusive Mode" button displayed on the display unit 17 of the PC 10.

[0123] If the determination result of step SP24 is negative, the processing circuit 21 executes the processing of step SP14. If the determination result of step SP24 is positive, the processing circuit 21 executes the occupancy mode release processing in step SP26. After the processing of step SP26 ends, the processing circuit 21 executes the processing of step SP4 again. The occupancy mode release processing will be described with reference to FIG. 18.

[0124] 18 is a flowchart showing an example of the operation of the exclusive mode release process. In step SP142, the processing circuit 21 releases the exclusive mode of the PC 10 that has been instructed to release the exclusive mode. After completing the process of step SP142, the processing circuit 21 determines in step SP144 whether or not administrative authority was set for the PC 10 that has released the exclusive mode before it transitioned to the exclusive mode. To achieve step SP144, the processing circuit 21 stores in the memory circuit 22 the identification information of the PC 10 that has been set administrative authority in step SP98. If the identification information stored in the memory circuit 22 matches the identification information of the PC 10 that has released the exclusive mode, the processing circuit 21 determines that the determination result in step SP144 is positive.

[0125] If the determination result in step SP144 is positive, the processing circuit 21 sets the PC that has been released from the exclusive mode as the administrative authority PC 10_m in step SP146. After the processing in step SP146 is completed, or if the determination result in step SP144 is negative, the processing circuit 21 ends the series of processes shown in FIG.

[0126] 3-3-2. Summary of the third modified example In the following description, the summary of the third modified example will be explained using an example in which the PC 10_1 is set as the administrative authority PC 10_m.

[0127] When the PC 10_1 is released from the exclusive mode, the projector 20 sets the management authority from the second device to the PC 10_1. The presenter U of the PC 10 that was set as the administrative authority PC10_m is likely to be the most familiar with operating the administrative authority of the projector 20 among the N presenters U. Therefore, according to the third modified example, administrative authority can be set to the PC 10 of the presenter U who is likely to be the most familiar with operating the administrative authority of the projector 20.

[0128] 3-4.Fourth variant 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.

[0129] 3-5. Fifth 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.

[0130] 3-6. Sixth Modification In the first modification and the mode based on the first modification, the occupied image in the second mode is an image that is a part of the image displayed on the display unit 17_o, but is not limited to this. For example, the occupied image in the second mode may be an image in which another image is superimposed on the image displayed on the display unit 17_o.

[0131] 3-7. Seventh Variation In the above-described embodiments, "when an instruction to disconnect the first communication is received from the management authority PC 10_m" is described as an example of "in response to the first communication being disconnected." However, a specific example of "in response to the first communication being disconnected" is not limited to "when an instruction to disconnect the first communication is received from the management authority PC 10_m." For example, when the first communication is disconnected, the projector 20 may set the management authority to the PC 10_2. In the eighth modification, "when the first communication is disconnected" is an example of "in response to the first communication being disconnected." "When the first communication is disconnected" includes a case where the first communication is disconnected because an instruction to disconnect the first communication is received from the management authority PC 10_m, a case where the first communication is disconnected as a result of the management authority PC 10_m moving, and a case where the first communication is disconnected because some obstacle occurs between the management authority PC 10_m and the projector 20.

[0132] Similarly, if the first communication, the second communication, and the fourth communication are established and the first communication is disconnected for some reason, the projector 20 may set the administrative authority to the PC 10 between PC10_2 and PC10_4 that has the strongest received signal strength of the wireless connection, or the PC 10 that established communication with the projector 20 earlier.

[0133] 4. Notes A summary of this disclosure is provided below.

[0134] (Supplementary Note 1) A method of controlling communication with a display device in a display system having three or more devices and a display device capable of communicating with the three or more devices, wherein the display device capable of displaying an image in a display area establishes a first communication with a first device of the three or more devices that has been set with administrative authority to manage authorization of communication with the display device, and a second communication with a second device of the three or more devices, 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 the display device is displaying an image in the display area, the display device transmits authorization request information indicating that authorization for the third communication has been requested to an administrative device that is a device set with the administrative authority, and when the administrative device receives the authorization request information, the administrative device outputs communication judgment information to the administrative device to allow a user of the administrative device to decide whether to approve the authorization of the third communication, and when the display device receives approval information from the administrative device indicating that the authorization for the third communication has been approved, the display device establishes the third communication. According to Supplementary Note 1, communication between the third device and the display device can be established while preventing the display of an image based on image data transmitted from the first device or the second device in the display area from being interrupted.

[0135] (Supplementary Note 2) The communication control method for a display device according to Supplementary Note 1, wherein the display device sets the administrative authority to the second device when the first communication is disconnected. According to Supplementary Note 2, when a third device requests connection to the display device in response to disconnection of communication with the first device for which administrative authority has been set, the user of the second device can determine whether to approve the authorization of communication between the third device and the display device.

[0136] (Supplementary Note 3) The communication control method for a display device according to Supplementary Note 1, wherein each of the three or more devices has a display unit, and when the first communication, the second communication, and the third communication are established, and the first device is set to a first mode in which an image based on image data transmitted from one of the three or more devices is occupying and displayed in the display area, the display device sets the management authority to the second device, and when the third device requests the display device to display an image in the display area while the image is being displayed in the display area, the display device refuses to display the image based on the image data transmitted from the third device. According to Supplementary Note 3, the display unit of the second device that is not in the occupancy mode displays communication determination information, thereby preventing a user of the first device in the first mode from being bothered.

[0137] (Supplementary Note 4) The communication control method for a display device according to claim 3, wherein the image that the first device causes the display device to display is the same as the image displayed on the display unit of the first device. According to Supplementary Note 4, it is possible to prevent communication determination information from being displayed on the same image as the image displayed on the display device, thereby preventing a user of a device set to the first mode from feeling annoyed.

[0138] (Supplementary Note 5) The communication control method for a display device according to Supplementary Note 3, wherein the image that the first device causes the display device to display is different from the image displayed on the display unit of the first device. According to Supplementary Note 5, it is possible to prevent communication determination information from being superimposed on information about the image being projected on the display device, thereby preventing the user of the device set to the first mode from feeling annoyed.

[0139] (Supplementary Note 6) The communication control method for a display device according to Supplementary Note 3, wherein the display device sets the administrative authority from the second device to the first device when the first device is released from the first mode. According to Supplementary Note 6, the administrative authority can be set to the device of a user who is most likely to be familiar with operating the administrative authority of the display device.

[0140] (Supplementary Note 7) The communication control method for a display device according to Supplementary Note 1, wherein the display device sets the management authority to the second device when a predetermined period of time has passed since the display device transmitted the authorization request information to the first device without the display device receiving either the approval information or denial information indicating that the authorization for the third communication has been denied. According to Supplementary Note 7, when the user of the first device overlooks the communication determination information or is too busy to operate the first device, a user of another device can temporarily determine whether to approve the authorization for communication between the third device and the display device.

[0141] (Supplementary Note 8) The method for controlling communication with a display device according to Supplementary Note 1, wherein the three or more devices are four or more devices, each having an input unit, and in addition to the first communication and the second communication being established, a fourth communication is established between a fourth device of the four or more devices and the display device, and when the display device receives an instruction to disconnect the first communication from the first device, the display device sets the administrative authority to one of the second device and the fourth device that is identified based on a result of an operation of the input unit of the first device by a user of the first device while the first communication is established. According to Supplementary Note 8, when a third device requests connection to the display device after the communication of the first device for which administrative authority has been set is disconnected, the user of the second device or the fourth device can determine whether to approve authorization for communication between the third device and the display device.

[0142] (Supplementary Note 9) The method for controlling communication with a display device according to Supplementary Note 1, wherein the three or more devices are four or more devices, each of which can communicate with the display device via wireless communication, and in addition to the first communication and the second communication being established, a fourth communication is established between a fourth device of the four or more devices and the display device, and when a predetermined period of time has passed since the display device transmitted the authorization request information to the first device without receiving either the approval information or denial information indicating that authorization for the third communication has been denied, or in response to disconnection of the first communication, the display device sets the administrative authority to one of the second device and the fourth device, which has a stronger received signal strength for the wireless connection, or which established communication with the display device earlier. According to Supplementary Note 9, when a third device requests connection to the display device after communication with the first device for which administrative authority has been set is disconnected, the user of the second device or the fourth device can determine whether to approve authorization for communication between the third device and the display device.

[0143] (Supplementary Note 10) A display system having three or more devices and a display device capable of communicating with the three or more devices, wherein the display device is capable of displaying an image in a display area, a first communication between a first device of the three or more devices and the display device and a second communication between a second device of the three or more devices and the display device are established, the first device is assigned administrative authority for managing connections to the display device, and when a third device of 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 authorization request information indicating that authorization for the third communication has been requested to an administrative device that is an apparatus assigned administrative authority, and when the administrative device receives the authorization request information, the administrative device outputs communication determination information to the administrative device to allow a user of the first device to determine whether to approve the third communication, and when the display device receives approval information from the administrative device indicating that the authorization for the third communication has been approved, the display device establishes the third communication. Supplementary Note 10 provides the same effect as Supplementary Note 1. [Explanation of symbols]

[0144] 1...display system, 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, BTN1, BTN2, BTN3, BTN4, BTN5, BTN6...buttons, CW...communication judgment image, DW, DWB...selection indication image, GC, GP, GP_1, GP_i...image, MP...venue, PR...projection area, PR1, PR2...control program, PRJ...projector communication control program, PRM...communication control program, RD, RD1, RD2...radio button, RG1...radio button group, SC...projection surface, STR1, STR2...character string, U...presenter, W...audience.

Claims

1. 1. A communication control method for a display device in a display system having three or more devices and a display device capable of communicating with the three or more devices, comprising: the display device capable of displaying an image in a display area establishes a first communication with a first device among the three or more devices, the first device having an administrative authority for managing authorization of communication with the display device, and a second communication with a second device among the three or more devices; 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 authorization request information indicating that authorization for the third communication has been requested to an administration device that is a device set as the administration authority; When the management device receives the authorization request information, the management device outputs communication determination information to the management device for allowing a user of the management device to determine whether or not to approve the authorization of the third communication; When the display device receives approval information indicating that the authorization for the third communication has been approved from the management device, the display device establishes the third communication. A method for controlling communication with a display device.

2. the display device sets the management authority to the second device in response to the first communication being disconnected. A method for controlling communication with the display device according to claim 1.

3. each of the three or more devices has a display unit; the display device is configured to: when the first device is set to a first mode in which an image based on image data transmitted from one of the three or more devices is occupying and displayed in the display area, the display device sets the management authority to the second device; When the display device receives a request from the third device to display an image in the display area while the display device is displaying an image in the display area, the display device refuses to display an image based on image data transmitted from the third device. A method for controlling communication with the display device according to claim 1.

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

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

6. When the first device is released from the first mode, the display device sets the management authority from the second device to the first device. A method for controlling communication with the display device according to claim 3.

7. When a predetermined period of time has elapsed since the display device transmitted the authorization request information to the first device without the display device receiving either the approval information or denial information indicating that authorization for the third communication has been denied, the display device sets the management authority to the second device. A method for controlling communication with the display device according to claim 1.

8. The three or more devices are four or more devices, each of the four or more devices has an input unit; In addition to the first communication and the second communication being established, a fourth communication is established between a fourth device among the four or more devices and the display device; When the display device receives an instruction to disconnect the first communication from the first device, the display device sets the management authority to one of the second device and the fourth device, which is identified based on a result of an operation of an input unit of the first device by a user of the first device while the first communication is established. A method for controlling communication with the display device according to claim 1.

9. The three or more devices are four or more devices, each of the four or more devices and the display device can communicate with each other via wireless communication; In addition to the first communication and the second communication being established, a fourth communication is established between a fourth device among the four or more devices and the display device; When a predetermined period of time has elapsed since the display device transmitted the authorization request information to the first device without the display device receiving either the approval information or denial information indicating that authorization for the third communication has been denied, or in response to the first communication being disconnected, the display device sets the management authority to one of the second device and the fourth device which has a stronger received signal of the wireless communication or which established communication with the display device earlier. A method for controlling communication with the display device according to claim 1.

10. A display system having three or more devices and a display device capable of communicating with the three or more devices, the display device is capable of displaying an image in a display area; a first communication between a first device among the three or more devices and the display device, and a second communication between a second device among the three or more devices and the display device are established; an administrative authority for managing a connection to the display device is set in the first 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 authorization request information indicating that authorization for the third communication has been requested to an administration device that is a device set as the administration authority; When the management device receives the authorization request information, the management device outputs communication determination information to the management device for allowing a user of the first device to determine whether to approve the authorization of the third communication; When the display device receives approval information indicating that the authorization for the third communication has been approved from the management device, the display device establishes the third communication. Display system.

Images