Method of controlling display device, and display device

The present application is based on, and claims priority from JP Application Serial Number 2019-107734, filed Jun. 10, 2019, the disclosure of which is hereby incorporated by reference herein in its entirety.

1. Technical Field

The present disclosure relates to a method of controlling a display device and a display device.

2. Related Art

In the past, there has been known a system of coupling a plurality of display devices using daisy chain connection to operate the plurality of display device in tandem with each other.

For example, JP-A-2012-19442 discloses a projector system having a main projector and a sub-projector coupled to each other using the daisy chain connection. In this projector system, an OSD token is provided to any one of the plurality of projectors, and the projector having the OSD token displays an OSD menu of the own projector.

When a function which can be executed when the daisy chain connection is established with another display device is installed in the display device, it is necessary for the user to switch the setting on whether the function is available or unavailable based on whether or not the daisy chain connection is established among the display devices. This operation is cumbersome for the user.

An aspect of the present disclosure is directed to a method of controlling a display device configured to display an image based on an image signal, the method including a selecting step of selecting an interface to which the image signal to be displayed by the display device out of a plurality of interfaces provided to the display device, a determining step of determining whether or not the interface selected is a compliant interface capable of establishing daisy chain connection, and a step of making transition of the display device to a state of preventing a function from being executed when the interface selected is not the compliant interface, and when the function which can be executed in a state in which the display device is coupled to another display device with the daisy chain connection is set available.

The method of controlling a display device described above may be configured such that, in the selecting step, when the function of the display device is set available, and the display device is set as a slave machine at start-up of the display device, the compliant interface is selected.

The method of controlling a display device described above may be configured to further include a step of detecting input of the image signal to the plurality of interfaces, wherein in the selecting step, when the function of the display device is set available and the display device is set as a slave machine, and when the input of the image signal to the compliant interface is detected in the detecting step, the compliant interface is selected.

The method of controlling a display device described above may be configured to further include a step of making the display device display an image based on the image signal input to any one of the interfaces, wherein when the compliant interface is selected in the selecting step in a state in which the display device is made to display the image based on the image signal input to the other interface than the compliant interface, display of the image based on the image signal input to the other interface is stopped, and the display device is made to display the image based on the image signal input to the compliant interface in the step of making the display device display the image.

The method of controlling a display device described above may be configured such that the compliant interface is an interface compliant with one of HDMI (registered trademark) and HDBaseT (registered trademark).

Another aspect of the present disclosure is directed to a display device configured to display an image based on an image signal including a plurality of interfaces to which an image signal is input, a selection section configured to select an interface to which the image signal to be displayed by the display device out of the plurality of interfaces, a determination section configured to determine whether or not the interface selected is a compliant interface set in advance compatible with daisy chain connection, and a function control section configured to prevent a function from being executed when the interface selected is not the compliant interface, and when the function which can be executed in a state in which the display device is coupled to another display device with the daisy chain connection is set available.

FIG. 1 is a system configuration diagram.

FIG. 2 is a block diagram showing a configuration of a projector.

FIG. 3 is a flowchart showing an operation of the projector.

FIG. 4 is a flowchart showing an operation of the projector.

An embodiment of the present disclosure will hereinafter be described with reference to the accompanying drawings.

FIG. 1 is a system configuration diagram according to an embodiment to which the present disclosure is applied.

The present embodiment is a system 1 provided with an image supply device 100 and a plurality of projectors 200 . The projectors 200 each correspond to an example of a “display device” according to the present disclosure. It is possible to couple the image supply device 100 and the plurality of projectors 200 to each other with the daisy chain. Further, it is also possible to make each of the projectors 200 operate alone. The daisy chain is a method of coupling a plurality of devices performing communication in series to each other with communication lines.

The image supply device 100 is a device of supplying an image signal to the projectors 200 . The projectors 200 are each a device for generating image light PL based on the image signal thus supplied, and then projecting the image light PL on a screen SC as a projection surface. On the screen SC, there is displayed an image corresponding to the image light PL. The screen SC is formed of a plane or a curtain, and the specific shape thereof is arbitrary. Further, the projection surface can be a uniform plane such as a wall surface, a ceiling surface, or a floor surface, or can also have a curved surface or an uneven surface.

As the image supply device 100 , it is possible to use, for example, a notebook PC (Personal Computer), a desktop PC, a tablet PC, a smartphone, and a PDA (Personal Digital Assistant). Further, as the image supply device 100 , it is also possible to use a video reproduction device, a DVD (Digital Versatile Disk) player, a Blu-ray disc player, a hard disk recorder, a television tuner, a set-top box for a CATV (Cable television), a video game device, or the like.

Although in FIG. 1 , there are shown the three projectors 200 , namely the projector 200 A, the projector 200 B, and the projector 200 C, as the projectors 200 , the number of the projectors 200 constituting the system 1 is arbitrary. Hereinafter, the projector 200 A, the projector 200 B, and the projector 200 C are described as the projectors 200 when a collective term therefor is used.

Further, FIG. 1 shows an example in which the three projectors 200 , namely the projectors 200 A, 200 B, and 200 C are laterally arranged in the lateral direction of the screen SC. The arrangement of the projectors 200 is not limited to the lateral arrangement shown in FIG. 1 , and it is also possible to adopt a matrix arrangement in which the four projectors 200 are arranged 2×2.

The projectors 200 A, 200 B, and 200 C project the image light PL in respective areas different from each other of the screen SC. The area in which the projector 200 A projects the image light PL is described as a projection area 10 A, the area in which the projector 200 B projects the image light PL is described as a projection area 10 B, and the area in which the projector 200 C projects the image light PL is described as a projection area 10 C.

When the image supply device 100 and the plurality of projectors 200 are coupled to each other with the daisy chain connection, the projector 200 located at the head of the daisy chain connection is referred to as a master machine. In other words, the projector 200 which is coupled to the image supply device 100 to receive the image signal from the image supply device 100 is referred to as the master machine. In the present embodiment, the projector 200 A operates as the master machine.

Further, in the posterior stage of the projector 200 A, there is coupled the projector 200 B, and in the posterior stage of the projector 200 B, there is coupled the projector 200 C. The projector 200 A is the projector 200 first in the connection order in the daisy chain connection. The projector 200 B is the projector 200 second in the connection order in the daisy chain connection. The projector 200 C is the projector 200 third in the connection order in the daisy chain connection. The projectors 200 B and 200 C which are second and third in the connection order function as slave machines.

The operation when the image supply device 100 and the plurality of projectors 200 are coupled to each other with the daisy chain connection will be described.

The projector 200 A receives the image signal supplied from the image supply device 100 , and then projects the image light PL based on the image signal thus received in the projection area 10 A. Further, the projector 200 A outputs the image signal which has been received from the image supply device 100 to the projector 200 B in the posterior stage. The projector 200 B receives the image signal from the projector 200 A, and then projects the image light PL based on the image signal thus received in the projection area 10 B. Further, the projector 200 B outputs the image signal which has been received from the projector 200 A to the projector 200 C in the posterior stage. The projector 200 C receives the image signal from the projector 200 B, and then projects the image light PL based on the image signal thus received in the projection area 10 C.

The projectors 200 A, 200 B, and 200 C are each provided with a plurality of interfaces. In other words, it is possible to couple a plurality of image supply devices 100 at the same time to each of the projectors 200 A, 200 B, and 200 C. Although FIG. 1 shows when each of the projectors 200 is provided with the three interfaces, the number of the interfaces provided to each of the projectors 200 is arbitrary, and the number of the interfaces provided to the projector 200 can be different between the projectors 200 .

The projector 200 A is provided with the three interfaces, namely the first interface 210 A, the second interface 220 A, and the third interface 230 A. The projector 200 B is provided with the three interfaces, namely the first interface 210 B, the second interface 220 B, and the third interface 230 B. The projector 200 C is provided with the three interfaces, namely the first interface 210 C, the second interface 220 C, and the third interface 230 C.

Hereinafter, the first interface 210 A, the second interface 220 A, and the third interface 230 A are described as the interfaces 207 A when a collective term therefor is used. Similarly, the first interface 210 B, the second interface 220 B, and the third interface 230 B are described as the interfaces 207 B when a collective term therefor is used. The first interface 210 C, the second interface 220 C, and the third interface 230 C are described as the interfaces 207 C when a collective term therefor is used. Further, the interfaces 207 A, 207 B, and 207 C are described as the interfaces 207 when a collective term therefor is used.

The projectors 200 A and 200 B are each provided with at least two HDMI interfaces. HDMI is a registered trademark. Further, the projector 200 C is provided with at least one HDMI interface. The HDMI interface is an interface compliant with the communication standard of HDMI, and is an interface capable of establishing the daisy chain connection. By establishing the daisy chain connection with the HDMI interface, it is possible to output the image signal as a digital signal having been received from a higher-level device directly to a lower-level device.

In the present embodiment, there will be described when the first interface 210 A and the second interface 220 A of the projector 200 A are each the HDMI interface. Further, there will be described when the first interface 210 B and the second interface 220 B of the projector 200 B are each the HDMI interface. Further, there will be described when the first interface 210 C is the HDMI interface in the projector 200 C.

The communication standards which the third interface 230 A, 230 B of the projectors 200 A, 200 B, and the second interface 220 C and the third interface 230 C of the projector 200 C are compliant with are arbitrary. To these interface, it is possible to apply any of the standards described below, for example.

The interfaces can each be, for example, an interface compliant with the standard of a digital interface such as DVI (Digital Visual Interface), HDMI, or Display Port. Further, the interface can be an analog interface such as VGA (Video Graphics Array), a D-terminal, or an S-terminal. Further, the interface can be a communication interface such as USB (Universal Serial Bus), Ethernet, or IEEE 1394. Further, the interface can also be a wireless communication interface such as HDBaseT, Bluetooth, wireless LAN including Wi-Fi, or NFC (Near Field Communication). Ethernet, HDBaseT, Bluetooth, and Wi-Fi are each a registered trademark.

FIG. 2 is a block diagram showing a configuration of the projector 200 A.

The projector 200 A, the projector 200 B, and the projector 200 C have substantially the same configurations. Therefore, the configuration of the projector 200 A will representatively be described, and the description of the configurations of other projectors 200 B, 200 C will be omitted.

It should be noted that since FIG. 2 shows the configuration of the projector 200 A, each of the constituents of the projector 200 A is denoted by a reference symbol attached with “A.” In the following description, “B” is attached to the reference symbol when describing the constituent of the projector 200 B, and “C” is attached to the reference symbol when describing the constituent of the projector 200 C. For example, a control section of the projector 200 A is described as a “control section 270 A,” and a control section of the projector 200 B is described as a “control section 270 B,” and a control section of the projector 200 C is described as a “control section 270 C.”

The first interface 210 A is provided with a connector 211 A and a transmission/reception circuit 213 A. The second interface 220 A is provided with a connector 221 A and a transmission/reception circuit 223 A. The third interface 230 A is provided with a connector 231 A and a transmission/reception circuit 233 A.

To the connectors 211 A, 221 A, and 231 A, there are coupled cables for coupling the projector 200 A and the external device to each other. In the present embodiment, since the first interface 210 A and the second interface 220 A are each the HDMI interface, the HDMI cables are coupled to the connectors 211 A and 221 A.

FIG. 2 shows the state in which the image supply device 100 , the projector 200 A, and the projector 200 B are coupled to each other with the daisy chain connection. For example, it is assumed that the image supply device 100 is coupled to the first interface 210 A, and the projector 200 B is coupled to the second interface 220 A as shown in FIG. 2 . In this case, the HDMI cable 20 coupled to the image supply device 100 is coupled to the connector 211 A, and the HDMI cable 30 coupled to the projector 200 B is coupled to the connector 221 A.

Further, it is also possible to couple the HDMI cable 20 coupled to the image supply device 100 to the connector 221 A, and couple the HDMI cable 30 coupled to the projector 200 B to the connector 211 A.

To the connectors 211 A, 221 A, and 231 A to which the cables are coupled, there are input the image signal and a control signal. The first interface 210 A, the second interface 220 A, and the third interface 230 A receive the image signal and the control signal thus input with the transmission/reception circuits 213 A, 223 A, and 233 A corresponding respectively to the interfaces 210 A, 220 A, and 230 A.

In the present embodiment, the first interface 210 and the second interface 220 A are each an interface compliant with the communication standard of HDMI. Therefore, the transmission/reception circuits 213 A and 223 A each perform processes such as a serial-to-parallel conversion and a signal level conversion of the image signal thus received. Further, the transmission/reception circuits 213 A and 223 A each retrieve the image data included in the image signal, and then output the image data thus retrieved to an image processing section 261 A. Further, the transmission/reception circuits 213 A and 223 A each output the control signal thus received to the control section 270 A. The control section 270 A controls each section of the projector 200 A based on the control signal thus input. Further, when the image signal has been input, the transmission/reception circuits 213 A and 223 A each output a notification signal of giving notice of input of the image signal to the control section 270 A.

Further, the transmission/reception circuits 213 A, 223 A, and 233 A are each coupled to the control section 270 A. Further, the transmission/reception circuit 213 A and the transmission/reception circuit 223 A are coupled to each other with a signal line.

It is assumed that the image supply device 100 is coupled to the first interface 210 A, the projector 200 B is coupled to the second interface 220 A as shown in FIG. 2 , and a daisy chain function described later is set available. In this case, the control section 270 A outputs the image signal received by the first interface 210 A to the second interface 220 A. The second interface 220 A outputs the image signal thus input to the projector 200 B via the HDMI cable 30 .

Further, it is assumed that the image supply device 100 is coupled to the second interface 220 A, the projector 200 B is coupled to the first interface 210 A, and the daisy chain function is set available. In this case, the control section 270 A makes the second interface 220 A output the image signal received by the second interface 220 A to the first interface 210 A. The first interface 210 A outputs the image signal thus input to the projector 200 B via the HDMI cable 20 .

Further, there will be described when the present embodiment has a configuration in which the third interface 230 A is provided with the connector 231 A compliant with the standard of an analog interface, and the transmission/reception circuit 233 A. To the transmission/reception circuit 233 A, there is input an analog image signal. The transmission/reception circuit 233 A is provided with, for example, an A/D converter, and converts the analog image signal thus input into digital image data with the A/D converter. The illustration of the A/D converter will be omitted. The transmission/reception circuit 233 A outputs the image data obtained by the conversion to the image processing section 261 A.

Further, the transmission/reception circuit 233 A detects that the image signal has been input to the A/D converter to output a notification signal of giving notice of input of the image signal to the control section 270 A.

Further, when it is assumed that the third interface 230 A is a communication interface, the transmission/reception circuit 233 A detects an electrical change in voltage or the like of the connector 231 A coupled to a signal line through which data is transmitted and received, and thus detects the input of the image signal. When the electrical change in voltage of the connector 231 A has been detected, the transmission/reception circuit 233 A outputs the notification signal of giving notice of input of the image signal to the control section 270 A. Further, it is also possible for the transmission/reception circuit 233 A to detect the input of the image signal when the transmission/reception circuit 233 A has received a transmission request for data from the external device coupled to the transmission/reception circuit 233 A.

The projector 200 A is provided with a remote control light receiving section 201 A and an operation panel 203 A as a reception section.

The remote control light receiving section 201 A receives an infrared signal transmitted by a remote controller not shown. The remote controller also functions as a part of the reception section. The remote control light receiving section 201 A outputs an operation signal corresponding to the infrared signal thus received to the control section 270 A. The operation signal is a signal corresponding to a switch of the remote controller operated.

The operation panel 203 A is disposed in, for example, a housing of the projector 200 A, and is provided with a variety of switches such as a power switch for switching ON and OFF the projector 200 A. When the switch in the operation panel 203 A is operated, the operation signal corresponding to the switch thus operated is input to the control section 270 A.

The projector 200 A is provided with a camera 205 A. The camera 205 A is a so-called digital camera. The camera 205 A is provided with an image sensor such as a CCD (Charge Coupled Device) or a CMOS (Complementary Metal Oxide Semiconductor). Further, the camera 205 A is provided with a data processing circuit for generating imaging data based on the light reception state of the image sensor. The camera 205 A outputs the imaging data thus generated to the control section 270 A.

The projector 200 A is provided with a projection section 240 A for projecting the image light PL, and a drive section 250 A for driving the projection section 240 A. The projection section 240 A is provided with a light source 241 A, a light modulation device 243 A, and an optical unit 245 A. The drive section 250 A is provided with a drive circuit 251 A and a light modulation device drive circuit 253 A.

As the light source 241 A, there is used a lamp light source such as a halogen lamp, a xenon lamp, or a super high-pressure mercury lamp. Further, as the light source 241 A, there can be used a solid-state light source such as an LED (Light Emitting Diode) or a laser light source.

Further, to the light source 241 A, there is coupled a drive circuit 251 A. The drive circuit 251 A is coupled to the light source 241 A and the control section 270 A, and supplies the light source 241 A with a drive current or a pulse in accordance with the control by the control section 270 A to put the light source 241 A on or off.

The light modulation device 243 A is provided with a light modulation element for modulating light emitted by the light source 241 A to generate the image light PL. The light modulation device 243 A emits the image light PL modulated by the light modulation element to the optical unit 245 A. As the light modulation element, it is possible to use, for example, a transmissive liquid crystal light valve, a reflective liquid crystal light valve, or a digital mirror device.

To the light modulation device 243 A, there is coupled a light modulation device drive circuit 253 A. The light modulation device drive circuit 253 A is coupled to the image processing section 261 A and the light modulation device 243 A, and draws the image corresponding to the image data input from the image processing section 261 A in the light modulation element frame by frame. For example, when the light modulation device 243 A is constituted by liquid crystal light valves, the light modulation device drive circuit 253 A is formed of a driver circuit for driving the liquid crystal.

The optical unit 245 A is provided with an optical element such as a lens or a mirror, and projects the image light PL modulated by the light modulation device 243 A toward the screen SC. Thus, the image based on the image light PL is imaged on the screen SC.

The projector 200 A is provided with the image processing section 261 A and a frame memory 263 A. The image processing section 261 A develops the image data received by any one of the first interface 210 A, the second interface 220 A, and the third interface 230 A on the frame memory 263 A. The frame memory 263 A is formed of, for example, an SDRAM (Synchronous Dynamic Random Access Memory).

The image processing section 261 A performs image processing on the image data developed on the frame memory 263 A. In the image processing performed by the image processing section 261 A, there are included, for example, a resolution conversion process or a resizing process, correction of a distortion aberration, a shape correction process, a digital zooming process, and an adjustment of the color shade or the luminance of the image. The image processing section 261 A performs the process designated by the control section 270 A, and performs the process using a parameter input from the control section 270 A as needed. Further, it is obviously possible for the image processing section 261 A to execute two or more of the processes described above in combination with each other. The image processing section 261 A retrieves the image data from the frame memory 263 A, and then outputs the image data thus retrieved to the light modulation device drive circuit 253 A.

The image processing section 261 A and the frame memory 263 A are formed of, for example, an integrated circuit. The integrated circuit includes an LSI, an ASIC (Application Specific Integrated Circuit), a PLD (Programmable Logic Device), an FPGA (Field-Programmable Gate Array), an SoC (System-on-a-Chip), and so on. Further, it is also possible for an analog circuit to be included in a part of the configuration of the integrated circuit, or it is also possible to adopt a configuration having the control section 270 A and the integrated circuit combined with each other.

The projector 200 A is provided with the control section 270 A. The control section 270 A is a computer provided with a storage section 280 A and a processor 290 A. The storage section 280 A is constituted by a volatile storage device such as a RAM (Random Access Memory), and a nonvolatile storage device such as a ROM (Read Only Memory) or a flash memory. The storage section 280 A stores a control program 281 A to be executed by the processor 290 A.

Further, the storage section 280 A stores configuration data 283 A. The configuration data 283 A is the data set by the user operating the remote controller or the control panel 203 A. In the configuration data 283 A, there are included the data in which whether the daisy chain function is available or unavailable is set, and information of the connection order in the daisy chain. In the case of the connection state shown in FIG. 1 , the connection order of the projector 200 A is set first, the connection order of the projector 200 B is set second, and the connection order of the projector 200 C is set third. The configuration data 283 A can be changed by the user operating the remote controller or the control panel 203 A.

The daisy chain function is a function of coupling a plurality of devices with the daisy chain. Specifically, there are included a function of outputting the image signal input from a higher-level device to a lower-level device, and a function of retrieving the image data from the image signal supplied from the higher-level device, and then clipping a part of the image data the display of which is taken care of by the projector 200 . Further, as the daisy chain function, there can also be included a function of determining whether or not a compliant interface has been selected as the interface 207 when the daisy chain function is set available.

Further, the compliant interface means an interface which can be coupled with the daisy chain connection. Specifically, the compliant interface is an interface capable of outputting the image signal input from the higher-level device to the lower-level device. In the present embodiment, the interface compliant with HDMI or HDBaseT compatible with HDMI is set as the compliant interface. In the case of HDMI or HDBaseT compatible with HDMI, it is possible to output the image signal as a digital signal having been received from the higher-level device directly to the lower-level device.

The processor 290 A is an arithmetic processing device formed of a CPU (Central Processing Unit) or an MPU (Micro Processing Unit). The processor 290 A executes the control program 281 A to control each section of the projector 200 A. The processor 290 A can be formed of a single processor, or can also be constituted by a plurality of processors. Further, the processor 290 A can also be formed of an SoC (System-on-a-Chip) integrated with a part or the whole of the storage section 280 A and other circuits. Further, the processor 290 A can also be formed of a combination of a CPU for executing a program and a DSP (Digital Signal Processor) for executing a predetermined arithmetic process. Further, it is also possible to adopt a configuration in which all of the functions of the processor 290 A are implemented in the hardware, or it is also possible to configure all of the functions of the processor 290 A using a programmable device.

The control section 270 A functions as a detection section 291 A, a selection section 293 A, a determination section 295 A, a function control section 297 A, and a display control section 299 A. These blocks represent the functions realized by the processor 290 A executing the command set described in the control program 281 A to perform arithmetic operations of the data and control with the blocks for descriptive purposes.

The detection section 291 A detects input of the image signal to the first interface 210 A, the second interface 220 A, and the third interface 230 A provided to the projector 200 A. The detection section 291 A detects the interface to which the image signal is currently input based on the notification signals input from the transmission/reception circuits 213 A, 223 A, and 233 A.

The selection section 293 A selects the interface 207 A to which the image signal representing the image light PL to be projected by the projection section 240 A is input out of the first interface 210 A, the second interface 220 A, and the third interface 230 A. The interface 207 A to be selected by the selection section 293 A is not required to have the image signal input at the moment when the selection section 293 A selects the interface 207 A. The interface 207 A which is selected by the selection section 293 A, and to which the image signal representing the image signal PL is input is referred to as a display source.

For example, the selection section 293 A stores the information of the interface 207 A which has been selected as the display source in the storage section 280 A immediately before the projector 200 A is powered off. Further, when the projector 200 A is powered on to start up the processor 290 A, the selection section 293 A refers to the storage section 280 A to select the interface 207 A which has been selected last time as the display source as the display source of this time.

Further, as an operation for other periods than the start-up period, the selection section 293 A switches the interface 207 A in which the input is detected to the display source when the input of the image signal is detected by the detection section 291 A in the state in which the input of the image signal is absent in the interface 207 A. Further, it is possible for the selection section 293 A to select the interface 207 A which is selected by the operation of the remote controller or the operation panel 203 A, as the display source.

The determination section 295 A refers to the configuration data 283 A to determine the configuration of the projector 200 A at the start-up of the processor 290 A. The determination section 295 A determines whether or not the connection order of the projector 200 A is first, namely the projector 200 A is the master machine, and the daisy chain function is set available. When the daisy chain function is set unavailable, the determination section 295 A does not change the display source, and sets the interface 207 A selected by the selection section 293 A as the display source without any change.

Further, when the connection order of the projector 200 A is first, and the daisy chain function is set available, the determination section 295 A determines whether or not the interface selected as the display source is the compliant interface. In the case of the present embodiment, the determination section 295 A determines whether or not the first interface 210 A or the second interface 220 A is selected as the display source.

The function control section 297 A controls the execution of the daisy chain function. In the daisy chain function for controlling the execution of the function control section 297 A, there are included, for example, an image signal output function and an image clipping function.

The image signal output function is a function of outputting the image signal received from the higher-level device to the lower-level device. For example, it is assumed that the image supply device 100 is coupled at a higher level than that of the projector 200 A, and the projector 200 B is coupled in the posterior stage of the projector 200 A as shown in FIG. 2 . In this case, the projector 200 A outputs the image signal which has been received from the image supply device 100 to the projector 200 B in the posterior stage.

Further, the image clipping function is a function of clipping partial image data as a part of the image data from the image data. The function control section 297 A outputs clipping range information for clipping the partial image data to the image processing section 261 A to make the image processing section 261 A perform the clipping of the partial image data. The clipping range information can be set by, for example, the user operating the remote controller or the operation panel 203 A, or can also be generated based on the imaging data of the camera 205 A.

When generating the clipping range information based on the imaging data by the camera 205 A, firstly, the projectors 200 A, 200 B, and 200 C each display a pattern image prepared in advance on the screen SC. Then, the projector 200 A, 200 B, and 200 C image the screen SC on which the pattern images are displayed with the cameras 205 A, 205 B, and 205 C to generate the imaging data, respectively. Subsequently, the projectors 200 A, 200 B, and 200 C detect the image ranges in which the pattern images displayed by the projectors 200 A, 200 B, and 200 C, respectively, from the imaging data. These image ranges form the whole of the range in which the images are displayed by the image light PL projected by the projectors 200 A, 200 B, and 200 C.

Subsequently, the projector 200 A alone displays the pattern image on the screen SC, and then images the screen SC on which the pattern image is displayed with the camera 205 A to generate the imaging data. The projector 200 A detects the range in which the pattern image is taken from the imaging data to thereby detect the image range in which the pattern image displayed by the projector 200 A is displayed. Each of the projectors 200 B, 200 C also performs this process. The projector 200 A generates the clipping range information for the projector 200 A based on the whole of the image range in which the projectors 200 A, 200 B, and 200 C perform the display and the image range in which the projector 200 A performs the display. Further, the process is similarly performed on the other projectors, namely the projectors 200 B, 200 C to generate the clipping range information, respectively.

Further, when a predetermined condition is fulfilled, the function control section 297 A inhibits the daisy chain function from being executed even when the daisy chain function is set available by the configuration data 283 A. This predetermined condition corresponds when the connection order of the projector 200 A set in the configuration data 283 A is first, and the daisy chain function is set available, but the display source thus selected is not the compliant interface.

It is possible for the function control section 297 A to rewrite the data related to the setting of the daisy chain function out of the configuration data 283 A with the data setting the daisy chain function unavailable to thereby inhibit the daisy chain function from being executed. Further, it is also possible for the function control section 297 A to refrain from instructing the image processing section 261 A, the first interface 210 A, or the second interface 220 A to execute the daisy chain function.

The display control section 299 A controls the image data to be input from the interface 207 A to the image processing section 261 A. The display control section 299 A selects the interface 207 A to which the image data is output from the image processing section 261 A based on the determination result by the determination section 295 A, and then instructs the interface 207 A thus selected to output the image data. The interface 207 A having received the instruction from the display control section 299 A retrieves the image data from the image signal received, and then outputs the image data thus retrieved to the image processing section 261 A.

Then, the operation of the control section 270 when the projector 200 is set as the slave machine will be described. The operation of the control section 270 B of the projector 200 B will hereinafter be described as a representative.

The selection section 293 B also stores the information of the interface 207 B which has been selected as the display source in the storage section 280 B immediately before the projector 200 B is powered off. Further, when the projector 200 B is powered on to be started up, the selection section 293 B refers to the storage section 280 B to select the interface 207 B which has been selected last time as the display source as the display source of this time.

When the daisy chain function is set unavailable, the determination section 295 B does not change the display source, and sets the interface 207 B selected by the selection section 293 B as the display source without any change.

Further, when the daisy chain function is set available, and the connection order of the projector 200 B is second or third, the determination section 295 B determines whether or not the interface selected as the display source is the predetermined compliant interface.

In the case of the projector 200 B and the projector 200 C as the slave machines, even when two or more interfaces compliant with HDMI are provided, predetermined one of the interfaces is set as the compliant interface. In the present embodiment, the first interface 210 B of the projector 200 B is set as the compliant interface, and the first interface 210 C of the projector 200 C is set as the compliant interface.

When the interface selected as the display source by the selection section 293 B is not the predetermined compliant interface, the determination section 295 B selects the first interface 210 B which is the predetermined compliant interface as the display source. Further, when the interface selected as the display source by the selection section 293 B is the predetermined compliant interface, the determination section 295 B does not change the interface 207 B selected as the display source.

When the daisy chain function is set unavailable, the function control section 297 B controls the interface 207 B and the image processing section 261 B so that the daisy chain function is not executed. Further, when the daisy chain function is set available, and the display source thus selected is the compliant interface, the function control section 297 B controls the interface 207 B and the image processing section 261 B so that the daisy chain function is executed.

Further, it is assumed that an interface other than the first interface 210 B such as the second interface 220 B is selected as the display source, and the image light PL based on the image signal input to the second interface 220 B is projected by the projection section 240 B.

Further, it is assumed that the interface 207 B to which the image signal is currently input is detected by the detection section 291 B, and the interface 207 B thus detected is the first interface 210 B. In this case, the selection section 293 B switches the display source from the second interface 220 B to the first interface 210 B.

When the display source is switched to the first interface 210 B, the display control section 299 B makes the second interface 220 B stop outputting the image data to the image processing section 261 B. Further, the display control section 299 B instructs the first interface 210 B to output the image data to the image processing section 261 B. Thus, even while displaying the image based on the image signal input to another interface 207 B, it is possible to stop to display the image to display an image based on the image signal input to the first interface 210 B.

FIG. 3 is a flowchart showing the operation of the projector 200 .

Here, the description is presented as the operation of the projector 200 without distinguishing the projector 200 A as the master machine and the projectors 200 B, 200 C as the slave machines from each other.

When the power switch of the projector 200 is turned on to supply the power to the projector 200 , the control section 270 starts up (step S 1 ) to start the process. Firstly, the control section 270 determines (step S 2 ) the interface 207 to which the image signal is currently input. For example, when receiving the image signal, the control section 270 determines the interface 207 to which the image signal is currently input based on the notification signal input from the transmission/reception circuits 213 , 223 , and 233 . Here, when there is no interface 207 to which the image signal is currently input, the control section 270 stores the data representing “none” in the storage section 280 . Further, when the interface 207 to which the image signal is currently input exists, the control section 270 stores the identification data of the interface 207 to which the image signal is currently input in the storage section 280 .

Then, the control section 270 sets (step S 3 ) the interface 207 which has been set as the display source before the projector 200 has been switched off. The step S 3 corresponds to a “selecting step” in the present disclosure.

Then, the control section 270 determines (step S 4 ) whether or not the image signal is currently input to the interface 207 set as the display source. When the image signal is currently input to the interface 207 set as the display source (YES in the step S 4 ), the control section 270 makes the transition to the determination in the step S 7 .

Further, when the image signal is not currently input to the interface 207 set as the display source (NO in the step S 4 ), the control section 270 determines (step S 5 ) whether or not there is any other interface 207 to which the image signal is currently input. When there is no other interface 207 to which the image signal is currently input (NO in the step S 5 ), the control section 270 makes the transition to the determination in the step S 7 without switching the display source.

Further, when there is another interface 207 to which the image signal is currently input (YES in the step S 5 ), the control section 270 changes (step S 6 ) the display source to the another interface 207 to which the image signal is currently input. Here, when there are two or more other interfaces 207 to which the image signal is currently input, it is possible to set the interface 207 high in priority as the display source based on the priority set in advance to each of such interfaces 207 .

Then, the control section 270 refers to the configuration data 283 to determine (step S 7 ) whether or not the daisy chain function is set available. When the daisy chain function is set unavailable (NO in the step S 7 ), the control section 270 terminates the processing flow. Further, when the daisy chain function is set available (YES in the step S 7 ), the control section 270 refers to the configuration data 283 to determine (step S 8 ) whether or not the projector 200 itself is the master machine. In other words, the control section 270 determines whether or not the projector 200 is the first projector in the daisy chain connection.

When the projector 200 is not the master machine (NO in the step S 8 ), namely when the projector 200 is the slave machine, the control section 270 determines (step S 9 ) whether or not the interface 207 set in advance is set as the display source. For example, the first interface 210 B of the projector 200 B and the first interface 210 C of the projector 200 C are each set as the interface 207 set in advance.

When the display source is not the interface 207 set in advance (NO in the step S 9 ), the control section 270 changes (step S 10 ) the display source to the interface 207 set in advance. The determinations in the steps S 9 and S 10 correspond to the “selecting step” in Claim 2 of the appended claims. Further, when the interface 207 set in advance is set as the display source (YES in the step S 9 ), the control section 270 makes the transition to the process in the step S 12 .

Further, when the projector 200 is the master machine (YES in the step S 8 ), the control section 270 determines (step S 11 ) whether or not the interface 207 set as the display source is the interface 207 compliant with the standard of HDMI. The step S 11 corresponds to a “determining step” in the present disclosure. When the interface 207 set as the display source is not the interface compliant with the standard of HDMI (NO in the step S 11 ), the control section 270 performs the control so that the daisy chain function is not executed. Specifically, the control section 270 performs the control so that the first interface 210 does not output the image signal received to the second interface 220 . Further, the control section 270 does not output the clipping range information to the image processing section 261 , and does not make the image processing section 261 execute the process of dividing the image data into partial image data. This process corresponds to a “step of making transition of the display device to a state of preventing a function from being executed” in the present disclosure.

Further, when the interface 207 set as the display source is the interface 207 compliant with the standard of HDMI (YES in the step S 11 ), the control section 270 determines (step S 12 ) whether or not the image signal is currently input to this interface 207 . When the image signal is not currently input to the interface 207 set as the display source (NO in the step S 12 ), the control section 270 terminates the processing flow without executing the daisy chain function. After terminating the processing flow, when the input of the image signal to the interface 207 set as the display source is detected, the control section 270 executes the daisy chain function. Further, when the image signal is currently input to the interface 207 set as the display source (YES in the step S 12 ), the control section 270 executes (step S 13 ) the daisy chain function.

FIG. 4 is a flowchart showing an operation of the projectors 200 B and 200 C as the slave machines. In particular, FIG. 4 shows an operation of the projectors 200 B and 200 C when the input of the image signal has been detected in the first interfaces 210 B, 210 C as the interface 207 set in advance. Since the projectors 200 B and 200 C perform the same operation, the operation of the projector 200 B will hereinafter be described as an example.

Firstly, the control section 270 B refers to the configuration data 283 B to determine (step S 21 ) whether or not the daisy chain function is available. When the daisy chain function is not set available (NO in the step S 21 ), the control section 270 B terminates the processing flow.

Further, when the daisy chain function is set available (YES in the step S 21 ), the control section 270 B determines (step S 22 ) whether or not the image signal is currently input to the first interface 210 B set in advance. The step S 22 corresponds to “a step of detecting input of the image signal” in Claim 3 of the appended claims. When the image signal is not input to the first interface 210 B set in advance (NO in the step S 23 ), the control section 270 B stands ready (step S 24 ) for a predetermined time set in advance. Subsequently, the control section 270 B determines (step S 21 ) again whether or not the daisy chain function is set available.

Further, when the image signal is currently input to the first interface 210 B set in advance (YES in the step S 23 ), the control section 270 B changes (step S 25 ) the display source to the first interface 210 B. In other words, even when, for example, the image signal is input to the third interface 230 B, and the image light PL based on the image signal thus input is currently projected on the screen SC, the control section 270 B stops projecting the image light PL to project the image light PL based on the image signal input to the first interface 210 B. After changing the display source, the control section 270 B executes (step S 26 ) the daisy chain function. In other words, the image light PL based on the image signal input to the first interface 210 B to which the display source has been changed is projected by the projection section 240 B. The steps S 25 and S 26 correspond to a “displaying step” in Claim 4 of the appended claims.

As described hereinabove, the projectors 200 according to the present embodiment are each provided with the first interface 210 , the second interface 220 , and the third interface 230 as the plurality of interfaces. Further, the projectors 200 are each provided with the selection section 293 , the determination section 295 , and the function control section 297 .

The selection section 293 selects the interface to which the image signal to be displayed by the projector 200 is input out of these plural interfaces.

The determination section 295 determines whether or not the interface selected by the selection section 293 is the compliant interface capable of being coupled with the daisy chain connection.

The function control section 297 prevents the daisy chain function which can be executed in the state in which the daisy chain connection is established from being executed when the condition is fulfilled. The condition corresponds to the case where the interface thus selected is not the compliant interface, and the daisy chain function, which can be executed in the state in which the projector 200 is coupled to the other projectors 200 with the daisy chain connection, is set available.

Therefore, when the interface thus selected is not the compliant interface, even when the daisy chain function, which can be executed in the state of being coupled with the daisy chain connection, is set available, the daisy chain function is not executed. Therefore, the usability for the user can be improved.

Further, when the daisy chain function of the projector 200 is set available, and the projector 200 is set as the slave machine at the start-up of the projector 200 , the selection section 293 selects the compliant interface.

Therefore, by setting the daisy chain function available and setting the projector 200 as the slave machine in advance, it is possible to select the compliant interface at the start-up of the projector 200 . Therefore, the usability for the user can be improved.

Further, the projectors 200 are each provided with the detection section 291 .

The detection section 291 detects the input of the image signal to the plurality of interfaces.

When the daisy chain function is set available and the projector 200 is set as the slave machine, and when the input of the image signal to the compliant interface is detected by the detection section 291 , the selection section 293 selects the compliant interface.

Therefore, when the input of the image signal to the compliant interface is detected, it is possible to make the projector 200 project the image light PL based on the image signal input to the compliant interface.

Further, the projectors 200 are each provided with the display control section 297 .

The display control section 297 makes the projection section 240 project the image based on the image signal input to any one of the plurality of interfaces.

When the compliant interface is selected by the selection section 293 in the state in which the projector 200 is made to display the image based on the image signal input to the other interface than the compliant interface, the display control section 297 stops displaying the image based on the image signal input to the other interface, and then makes the projection section 240 project the image based on the image signal input to the compliant interface.

Therefore, even when the image light PL based on the image signal input to the other interface is projected, when the input of the image signal to the compliant interface is detected, it is possible to project the image light PL based on the image signal input to the compliant interface.

Further, the compliant interface is the interface compliant with HDMI or HDBaseT.

Therefore, the image signal digitally input thereto can be output to the projector 200 in the posterior stage without any change.

The embodiment described above is a preferred embodiment of the present disclosure. It should be noted that the embodiment described above is not a limitation, and a variety of modifications can be implemented within the scope or the spirit of the present disclosure.

For example, in the embodiment described above, there is described when the interfaces 207 provided to the projectors 200 are the interfaces compatible with a wired system. Further, there is described when the compliant interfaces are the interfaces compatible with the HDMI interface. As the modified example, it is possible for the compliant interface to be the interface compatible with HDBaseT as the wireless standard compliant with HDMI. For example, it is possible for at least one of the first interface 210 A and the second interface 220 A of the projector 200 A to be the interface compliant with HDBaseT. The same applies to the projectors 200 B and 200 C.

Further, in the embodiment described above, the light modulation element provided to the light modulation device 243 can be a transmissive liquid crystal panel or can also be a reflective liquid crystal panel. Further, it is also possible for the light modulation element to have a configuration using a digital mirror device, or to have a configuration having the digital mirror device and a color wheel combined with each other. Further, besides the liquid crystal panel or the DMD, configurations capable of modulating the light emitted by the light source can also be adopted as the light modulation device 243 .

Further, each of the functional sections of the projector 200 A shown in FIG. 2 is for showing the functional configuration, and the specific mounting forms are not particularly limited. In other words, it is not necessarily required to install the hardware corresponding individually to each of the functional sections, but it is obviously possible to adopt a configuration of realizing the functions of the plurality of functional sections by a single processor executing a program. Further, a part of the function realized by software in the embodiment described above can also be realized by hardware, and a part of the function realized by hardware can also be realized by software. Besides the above, the specific detailed configuration of each of other sections than the projector can arbitrarily be modified within the scope or the spirit of the present disclosure.

Further, the processing units of the flowcharts shown in FIG. 3 and FIG. 4 are obtained by dividing the process of the projector 200 in accordance with major processing contents in order to make the process of the projector 200 easy to understand. The scope of the present disclosure is not limited by the way of the division or the names of the processing units shown in the flowcharts of FIG. 3 and FIG. 4 . Further, the process of the control section 270 can also be divided into a larger number of processing units, or can also be divided so that one processing unit includes a larger amount of process in accordance with the processing contents. Further, the processing sequence of the flowchart described above is not limited to the illustrated example.

Further, when realizing the method of controlling a display device using a computer provided to the projector 200 , it is also possible to configure the program to be executed by the computer as an aspect of a recording medium, or an aspect of a transmission medium for transmitting the program. As the recording medium, there can be used a magnetic or optical recording medium, or a semiconductor memory device. Specifically, there can be cited a portable or rigid recording medium such as a flexible disk, an HDD (Hard Disk Drive), a CD-ROM, a DVD, a Blu-ray disc, a magnetooptic disc, a flash memory, or a card-type recording medium. Further, the recording medium described above can also be a RAM, or a nonvolatile storage device such as a ROM or the HDD as an internal storage device provided to the server device. Blu-ray is a registered trademark.