Projector and control method of projector for notifying image supply device of resolution information

A projector includes: a projecting section projecting a second image based on image information onto a projection surface onto which a first image is projected by another projector; a generating section generating resolution information indicating a resolution different between a first mode in which the first image and the second image are portions of an image indicated by the image information and the second image is connected with the first image and a second mode in which the first image and the second image are the image indicated by the image information and the second image is superimposed on the first image; and a notifying section notifying an image supply device supplying the image information of the resolution information generated by the generating section.

The present application is based on, and claims priority from JP Application Serial Number 2018-164208, filed Sep. 3, 2018, the disclosure of which is hereby incorporated by reference herein in its entirety.

BACKGROUND

1. Technical Field

The present disclosure relates to a projector and a control method of a projector.

2. Related Art

JP-A-2013-117631 discloses a projection system that connects projection images projected by a plurality of projectors to display a tiling image. In this projection system, the plurality of projectors are connected in a cascade fashion, and the top projector in the cascade connection calculates the resolution of the tiling image and generates extended display identification data (EDID) indicating the resolution of the tiling image. The top projector causes an image supply device to read the EDID. The image supply device generates, based on the EDID, image information indicating the tiling image.

Examples of a method of displaying one image, as a whole, using projection images projected by a plurality of projectors include, in addition to the method of displaying the tiling image as disclosed in JP-A-2013-117631, a method of displaying a stack image by superimposing a plurality of projection images of the same image.

The projection system disclosed in JP-A-2013-117631 can generate only the EDID indicating the resolution of the tiling image, and therefore cannot cause the image supply device to generate image information corresponding to the resolution of a stack image.

SUMMARY

A projector according to one aspect of the present disclosure includes: a projecting section projecting a second image based on image information onto a projection surface onto which a first image is projected by another projector; a generating section generating resolution information indicating a resolution different between a first mode in which the first image and the second image are portions of an image indicated by the image information and the second image is connected with the first image and a second mode in which the first image and the second image are the image indicated by the image information and the second image is superimposed on the first image; and a notifying section notifying an image supply device supplying the image information of the resolution information generated by the generating section.

A control method of a projector according to one aspect of the present disclosure includes: projecting a second image based on image information onto a projection surface onto which a first image is projected by another projector; generating resolution information indicating a resolution different between a first mode in which the first image and the second image are portions of an image indicated by the image information and the second image is connected with the first image and a second mode in which the first image and the second image are the image indicated by the image information and the second image is superimposed on the first image; and notifying an image supply device supplying the image information of the resolution information.

DESCRIPTION OF EXEMPLARY EMBODIMENTS

A: First Embodiment

FIG. 1is a diagram showing one example of a multi-projection system1including a first projector200aaccording to a first embodiment.

The multi-projection system1includes a personal computer (PC)100, the first projector200a, a second projector200b, and a third projector200c. In the following, when there is no need to distinguish the first projector200a, the second projector200b, and the third projector200c, each of the first projector200a, the second projector200b, and the third projector200cis referred to as “projector200”. In the multi-projection system1, the number of the projectors200is not limited to three, and may be two or more.

The PC100is one example of an image supply device. The image supply device may be generally referred to as a source device. The image supply device is not limited to the PC100. For example, a digital versatile disc (DVD) player may be used as the image supply device. The PC100is connected with the first projector200avia a first cable400a. The PC100supplies image information indicating an image to the first projector200a.

The PC100, the first projector200a, the second projector200b, and the third projector200care connected in this order in a so-called cascade fashion. In the following, the connection in a cascade fashion is referred to as “cascade connection”. Here, the position of the top in the cascade connection, that is, the position of the PC100means an “upstream” position, and the position of the bottom, that is, the position of the third projector200cmeans a “downstream” position. The first projector200ais connected with the second projector200bvia a second cable400b. The first projector200ais one example of another projector. The second projector200bis connected with the third projector200cvia a third cable400c.

Each of the first projector200a, the second projector200b, and the third projector200cprojects a projection image onto a projection surface such as a screen. Hereinafter, the projection image of the first projector200ais referred to as “first projection image”. The projection image of the second projector200bis referred to as “second projection image”. The projection image of the third projector200cis referred to as “third projection image”. The first projection image is one example of a first image. The second projection image is one example of a second image.

The multi-projection system1has a tiling mode and a stack mode. The tiling mode is one example of a first mode. The stack mode is one example of a second mode.FIG. 2is a diagram showing one example of a projection image of the multi-projection system1in the tiling mode.FIG. 3is a diagram showing one example of a projection image of the multi-projection system1in the stack mode.

In the tiling mode, each of the first projection image500a, the second projection image500b, and the third projection image500cis a portion of an image indicated by image information supplied from the PC100, that is, a partial image of the image, and the first projection image500a, the second projection image500b, and the third projection image500care connected to one another on a projection surface300.

In the example shown inFIG. 2, the image information supplied from the PC100indicates the image of “ABC”. The first projection image500arepresents “A” as a portion of “ABC”. The second projection image500brepresents “B” as a portion of “ABC”. The third projection image500crepresents “C” as a portion of “ABC”. On the projection surface300, the first projection image500a, the second projection image500b, and the third projection image500care connected to one another to generate the tiling image of “ABC”. The tiling image is one example of a third image.

In the embodiment, the tiling image is generated by connecting the first projection image500a, the second projection image500b, and the third projection image500cin the horizontal direction of an image. However, a form in which a plurality of projection images are connected for generating a tiling image is not limited to a form in which the plurality of projection images are connected in the horizontal direction, but may be a form in which the plurality of projection images are connected in the vertical direction or may be a from in which the plurality of projection images are connected in the vertical direction and the horizontal direction.

In the stack mode, each of the first projection image500a, the second projection image500b, and the third information supplied from the PC100, and the first projection image500a, the second projection image500b, and the third projection image500care superimposed on one another on the projection surface300.

In the example shown inFIG. 3, the image information supplied from the PC100indicates the image of “A”. Each of the first projection image500a, the second projection image500b, and the third projection image500crepresents “A.”. On the projection surface300, the first projection image500a, the second projection image500b, and the third projection image500care superimposed on one another to generate the stack image of “A”. The stack image is one example of a fourth image.

Here, the projection position of the first projection image500a, the projection position of the second projection image500b, and the projection position of the third projection image500care adjusted by a user in each of the tiling mode and the stack mode.

A2: Configuration Example of PC100

FIG. 4is a diagram showing one example of the PC100. The PC100includes a PC-side bus101, a PC-side manipulating section102, a PC-side storage section103, a PC-side control section104, a PC-side communication section105, a video controller106, and a PC-side image transmitting section107.

The PC-side manipulating section102, the PC-side storage section103, the PC-side control section104, and the video controller106are connected to each other via the PC-side bus101. The PC-side manipulating section102is, for example, a keyboard or a mouse, and receives a user's manipulation. The PC-side storage section103is a computer-readable recording medium. The PC-side storage section103stores a program to define the operation of the PC100, and various kinds of information.

The PC-side control section104is a computer such as a central processing unit (CPU). The PC-side control section104may include one or a plurality of processors. The PC-side control section104controls the PC100by reading and executing the program stored by the PC-side storage section103.

The PC-side communication section105communicates with an external device as a receiving side of image information. In the embodiment, the external device is the first projector200a. The PC-side communication section105reads, from the external device, EDID whose format is standardized by the video electronics standards association (VESA).

The EDID indicates characteristic information of a receiving-side device that receives the image information. The EDID includes resolution information indicating an image resolution that the receiving-side device can support. The image resolution is represented by the form of the product of the number of pixels in the horizontal direction and the number of pixels in the vertical direction in the image. Examples of the resolution include, for example, 1920×1080, 1280×720, and 720×480.

The video controller106is controlled by the PC-side control section104and generates image information. For example, the video controller106generates image information having a resolution indicated by the EDID read by the PC-side communication section105.

The PC-side image transmitting section107transmits the image information generated by the video controller106to the external device, specifically to the first projector200a.

A3: Configuration Example of First Projector200ato Third Projector200c

FIG. 5is a diagram showing one example of the first projector200ato the third projector200c.

The first projector200a, the second projector200b, and the third projector200chave the same configuration except for resolutions that the projectors can support. The resolutions that the first projector200a, the second projector200b, and the third projector200ccan support may be the same as each other.

To avoid a repetitive description, among the first projector200a, the second projector200b, and the third projector200c, the configuration of the first projector200awill be mainly described below.

The first projector200aincludes a projection-side bus201, a downstream communication section202, an EDID storage section203, an upstream communication section204, a splitter205, an image processing section206, a projecting section207, a projection-side image transmitting section208, a projection-side manipulating section209, an information storage section210, and a processing section211.

Here, the term “downstream” means downstream of the cascade connection. For example, “downstream” of the first projector200ameans the second projector200bside. “Downstream.” of the second projector200bmeans the third projector200cside.

The term “upstream.” means “upstream.” of the cascade connection. For example, “upstream.” of the first projector200ameans the PC100side. “Upstream.” of the second projector200bmeans the first projector200aside.

The downstream communication section202, the EDID storage section203, the upstream communication section204, the splitter205, the image processing section206, the projecting section207, the projection-side image transmitting section208, the projection-side manipulating section209, the information storage section210, and the processing section211are connected to each other via the projection-side bus201.

The downstream communication section202communicates with a cascade-connected downstream device. Hereinafter, the cascade-connected downstream device is referred to as “downstream device”. The downstream communication section202reads EDID from the downstream device. Specifically, the downstream communication section202requests EDID from the downstream device, and receives, in response to the request, the EDID notified from the downstream device. The downstream communication section202is one example of a receiving section. The EDID of each of the second projector200band the third projector200cis one example of support information.

The EDID storage section203stores EDID. In the EDID stored in the EDID storage section203, initial EDID initially set in the first projector200aand EDID read by the downstream communication section202from the downstream device are reflected. The initial EDID initially set in the first projector200aincludes, for example, resolution information indicating a resolution that the first projector200acan support. The initial EDID initially set in the first projector200ais stored in the information storage section210of the first projector200a.

The upstream communication section204communicates with a cascade-connected upstream device. Hereinafter, the cascade-connected upstream device is simply referred to as “upstream device”. The upstream communication section204notifies, in response to a request from the upstream device, the upstream device of the EDID stored in the EDID storage section203. The upstream communication section204is one example of a notifying section.

The splitter205is an image distributing section. The splitter205distributes image information received from the upstream device to the image processing section206and the projection-side image transmitting section208.

The image processing section206performs image processing on image information. Examples of the image processing include, for example, a trapezoidal distortion correction process to correct the distortion of a projection image. The image processing is not limited to the trapezoidal distortion correction process, and can be appropriately changed.

In the tiling mode, the image processing section206cuts out, from the image information provided from the splitter205, a portion whose projection is taken charge of by the first projector200a, performs image processing on the image information after being cut out, and generates an image signal. Cut-out portion information indicating the portion whose projection is taken charge of by the first projector200ais stored in the information storage section210. The image processing section206executes the cutting out described above using the cut-out portion information stored in the information storage section210.

In the stack mode, the image processing section206performs, without performing cutting out on the image information provided from the splitter205, image processing on the image information, and generates an image signal.

The projecting section207projects, onto the projection surface300, an image according to the image signal generated by the image processing section206. The projection-side image transmitting section208transmits the image information provided from the splitter205to the downstream device. The projection-side manipulating section209is, for example, various manipulating buttons or manipulating keys, or a touch panel. The projection-side manipulating section209receives a user's input manipulation.

The information storage section210is a computer-readable recording medium. The information storage section210stores a program to define the operation of the first projector200a, and various kinds of information.

The processing section211is a computer such as a CPU. The processing section211may include one or a plurality of processors. The processing section211realizes a mode managing section212, a generating section213, and a projection control section214by reading and executing the program stored by the information storage section210.

The mode managing section212manages, for example based on a manipulation accepted by the projection-side manipulating section209, whether the first projector200ais in the tiling mode or the stack mode. Moreover, the mode managing section212manages, based on a manipulation accepted by the projection-side manipulating section209, whether the first projector200ais positioned most upstream of the cascade connection among the first projector200a, the second projector200b, and the third projector200c.

The generating section213generates, for example, resolution information indicating a resolution different between the tiling mode and the stack mode. In the embodiment, the generating section213generates resolution information included in EDID.

The projection control section214controls the image processing section206and the projecting section207to control the projection of an image by the first projector200a.

A4: Configuration Example of Projecting Section207

FIG. 6is a diagram showing one example of the projecting section207. The projecting section207includes a light valve drive section11, a light source drive section12, a light source13, a liquid crystal light valve14R for red, a liquid crystal light valve14G for green, a liquid crystal light valve14B for blue, and a projection optical system15. Hereinafter, there is no need to distinguish the liquid crystal light valve14R for red, the liquid crystal light valve14G for green, and the liquid crystal light valve14B for blue from one another, each of the liquid crystal light valve14R for red, the liquid crystal light valve14G for green, and the liquid crystal light valve14B for blue is simply referred to as “liquid crystal light valve14”.

The light valve drive section11drives the liquid crystal light valve14based on an image signal. The light source drive section12drives the light source13.

The light source13is a xenon lamp, an extra-high-pressure mercury lamp, a light emitting diode (LED), a laser light source, or the like. Variations in the brightness distribution of light emitted from the light source13are reduced by an integrator optical system (not shown), and thereafter, the light is separated by a color separating optical system (not shown) into color light components of red, green, and blue, which are three primary colors of light. The red color light component is incident on the liquid crystal light valve14R for red. The green color light component is incident on the liquid crystal light valve14G for green. The blue color light component is incident on the liquid crystal light valve14B for blue.

The liquid crystal light valve14includes, for example, a liquid crystal panel in which liquid crystal is present between a pair of transparent substrates. The liquid crystal light valve14includes a rectangular pixel region14aincluding a plurality of pixels14ppositioned in a matrix. In the liquid crystal light valve14, a drive voltage can be applied to the liquid crystal for each of the pixels14p. When the light valve drive section11applies, to each of the pixels14p, the drive voltage based on an image signal input from the image processing section206, each of the pixels14pis set to a light transmittance based on the image signal. For this reason, the light emitted from the light source13is modulated by passing through the pixel region14a, and an image based on the image signal is formed for each color light.

The images of the respective colors are combined by a color combining optical system (not shown) for each of the pixels14p, and a projection image as a color image is generated. The projection image is projected by the projection optical system15onto the projection surface300.

FIG. 7is a flowchart for explaining an operation relating to most-upstream projector setting in the projector200. Here, the term “most-upstream projector” means the top of the plurality of cascade-connected projectors200, and more specifically means the projector200to which image information is supplied from the PC100among the plurality of projectors200. In the example shown inFIG. 1, the first projector200ais the most-upstream projector.

When the projection-side manipulating section209receives a most-upstream projector setting manipulation to set this projector200as the most-upstream projector of the cascade connection among the first projector200a, the second projector200b, and the third projector200cin Step S11, the mode managing section212executes setting of the most-upstream projector in Step S12.

Subsequently, in Step S13, the mode managing section212notifies, using the downstream communication section202, another projector200of most-upstream projector information indicating that this projector200is the most-upstream projector, and causes the another projector200to hold the most-upstream projector information.

Moreover, when the projection-side manipulating section209receives a non-most-upstream projector setting manipulation to set this projector200as a non-most-upstream projector in Step S14, the mode managing section212cancels the setting of the most-upstream projector and executes the setting of the non-most-upstream projector in Step S15.

On the other hand, when the projection-side manipulating section209does not receive both the most-upstream projector setting manipulation and the non-most-upstream projector setting manipulation, the mode managing section212does not change the setting of the most-upstream projector and the non-most-upstream projector and maintains the setting.

A6: Mode Setting Operation

FIG. 8is a flowchart for explaining a mode setting operation in the projector200.

When the projection-side manipulating section209receives a tiling mode setting manipulation to set the tiling mode from the user in Step S21, the mode managing section212sets an operating mode to the tiling mode in Step S22.

Subsequently, when the projection-side manipulating section209receives tiling information used for generating a tiling image in Step S23, the mode managing section212notifies, using the upstream communication section204, the most-upstream projector200of the tiling information and causes the most-upstream projector200to hold the tiling information in Step S24.

FIG. 9shows one example of the tiling information held in the information storage section210by the most-upstream projector200, that is, by the first projector200a.

In this example, the numbers of projection images arranged are “3” in the horizontal direction and “1” in the vertical direction. Information on the numbers of projection images is shown in the column of the number of horizontal images and the column of the number of vertical images in the tiling information. Moreover, the positions of projection images are arranged from the left in order of the first projection image500a, the second projection image500b, and the third projection image500c. Information on the positions of projection images is shown in the column of the horizontal position of the projection image and the column of the vertical position of the projection image in the tiling information.

The tiling information is applicable not only to a tiling image composed of 3×1 images in the horizontal and vertical directions but also to another tiling image.

The description returns toFIG. 8. When the projection-side manipulating section209receives a stack mode setting manipulation to set the stack mode in Step S25, the mode managing section212sets the operating mode to the stack mode in Step S26.

On the other hand, when the projection-side manipulating section209does not receive both the tiling mode setting manipulation and the stack mode setting manipulation, the mode managing section212does not change the operating mode and maintains the operating mode.

A7: Operation to Acquire EDID

FIG. 10is a flowchart for explaining an operation relating to EDID in the projector200.

For example, when the projector200is connected with the downstream device, the downstream communication section202acquires EDID from the EDID storage section203of the downstream device in Step S31. When the downstream device is not present, Step S31is omitted.

Subsequently, when the setting of the most-upstream projector is not performed in Step S32, the generating section213updates EDID stored in the EDID storage section203of this projector200in Step S37.

In Step S37where the setting of the most-upstream projector is not performed, the generating section213updates the EDID stored in the EDID storage section203to a combination of the initial EDID previously stored in the information storage section210and the EDID of the downstream device, which is acquired in Step S31.

For example, in the second projector200b, the EDID stored in the EDID storage section203is updated to a combination of initial EDID of the second projector200band initial EDID of the third projector200c.

Subsequently, in Step S38, the generating section213transmits, using the upstream communication section204, an EDID reading instruction to instruct reading of EDID to the upstream device. When the upstream device receives the EDID reading instruction, the upstream device executes the operation shown inFIG. 10and acquires, in Step S31, the EDID of the projector200present downstream.

For example, in a situation in which the initial EDID of each of the second projector200band the third projector200cis stored in the EDID storage section203of the second projector200b, the first projector200aas the upstream device acquires the initial EDID of each of the second projector200band the third projector200c.

On the other hand, in a case in which the setting of the most-upstream projector is performed in Step S32, when the operating mode is the tiling mode in Step S33, the generating section213determines the resolution of a tiling image in Step S34.

The generating section213determines the resolution of the tiling image with reference to the initial EDID of each of the first projector200a, the second projector200b, and the third projector200cand the tiling information stored in the information storage section210.

In this example, the generating section213first specifies the maximum resolution among supportable resolutions for each initial EDID. Subsequently, the generating section213determines the horizontal resolution of the tiling image by adding up the horizontal resolutions of the maximum resolutions, that is, the numbers of horizontal pixels. Subsequently, the generating section213determines the maximum vertical resolution among the vertical resolutions of the maximum resolutions, that is, the maximum number of vertical pixels as the vertical resolution of the tiling image. Further, the generating section213determines the minimum vertical resolution among the vertical resolutions of the maximum resolutions, that is, the minimum number of vertical pixels as the effective vertical resolution of the tiling image. Here, in the tiling image, a portion that does not fall within the effective vertical resolution is a black region.

Subsequently, in Step S35, the generating section213generates, based on each initial EDID, the tiling information, and the resolution of the tiling image, cut-out portion information of each of the first projector200a, the second projector200b, and the third projector200c, and notifies the second projector200band the third projector200cof the cut-out portion information.

The generating section213determines a cut-out position in the horizontal direction based on the horizontal resolution of each of the maximum resolutions, and determines a cut-out position in the vertical direction based on the vertical resolution of each of the maximum resolutions. When the generating section213determines the cut-out position in the vertical direction, the generating section213determines the cut-out position so as to make the black region not falling within the effective vertical resolution small.

In the first projector200a, the generating section213stores the cut-out portion information of the first projector200ain the information storage section210. In the second projector200b, the generating section213stores the cut-out portion information of the second projector200b, which is notified from the first projector200a, in the information storage section210. In the third projector200c, the generating section213stores the cut-out portion information of the third projector200c, which is notified from the first projector200a, in the information storage section210.

On the other hand, when the operating mode is the stack mode in Step S33, the generating section213determines, with reference to the EDID of all of the cascade-connected projectors200, a common resolution that all of the projectors200can support, as the resolution of a stack image in Step S36.

For example, when the EDID of the first projector200aindicates “1920×1080”, “1280×720”, and “720×480” as resolutions, the EDID of the second projector200bindicates “1280×720” and “720×480” as resolutions, and the EDID of the third projector200cindicates “720×480” as a resolution, the generating section213determines “720×480” as the common resolution.

Here, the common resolution may include a plurality of resolutions. For example, it is assumed that the EDID of the first projector200aindicates “1920×1080”, “1280×720”, and “720×480” as resolutions, and the EDID of the second projector200bindicates “1280×720” and “720×480” as resolutions. In addition, when the EDID of the third projector200cindicates “1280×720” and “720×480” as resolutions, the generating section213determines “1280×720” and “720×480” as the common resolution.

When Step S35is completed and when Step S36is completed, Step S37is executed.

In Step S37executed after the completion of Step S35, the generating section213generates first resolution information indicating the resolution of the tiling image, and updates the EDID stored in the EDID storage section203to EDID including the first resolution information.

On the other hand, in Step S37executed after the completion of Step S36, the generating section213generates second resolution information indicating the resolution of the stack image, that is, the common resolution, and updates the EDID stored in the EDID storage section203to EDID including the second resolution information.

When Step S37is completed, Step S38described above is executed.

A8: Operation of PC100

FIG. 11is a flowchart for explaining an operation of the PC100to generate and supply image information.

When the PC-side communication section105of the PC100receives an EDID reading instruction from the first projector200aserving as the downstream device in Step S41, the PC-side control section104causes the PC-side communication section105to acquire EDID of the first projector200ain Step S42.

Specifically, the PC-side communication section105first requests the EDID from the first projector200a. Subsequently, the upstream communication section204of the first projector200areads, in response to the request for the EDID, the EDID stored in the EDID storage section203, and transmits the EDID to the PC100. The PC-side communication section105receives the EDID from the first projector200a.

Subsequently, in Step S43, the video controller106generates image information according to the EDID received by the PC-side communication section105. Specifically, the video controller106generates image information having a resolution indicated by the EDID. Here, when the EDID received by the PC-side communication section105indicates a plurality of resolutions, the video controller106generates image information having the maximum resolution among the plurality of resolutions.

Subsequently, in Step S44, the PC-side image transmitting section107supplies the image information generated by the video controller106to the first projector200a.

A9: Image Projecting Operation of Projector200

FIG. 12is a flowchart for explaining an operation of the projector200to project an image.

When the splitter205receives image information from the upstream device, the splitter205distributes the image information to the image processing section206and the projection-side image transmitting section208.

When the operating mode is the tiling mode in Step S51, the projection control section214causes the image processing section206to execute a process for cutting out, from the image information, a portion whose projection is taken charge of by the projector200in Step S52. The image processing section206executes the cut-out process using the cut-out portion information stored in the information storage section210.

On the other hand, when the operating mode is not the tiling mode in Step S51, Step S52is skipped.

Subsequently, in Step S53, the projecting section207projects an image. In the tiling mode, the image processing section206first performs image processing on the image information after being cut out in Step S51and generates an image signal. In the stack mode, the image processing section206performs, without performing cutting out on the image information provided from the splitter205, image processing on the image information and generates an image signal. The projecting section207projects an image according to the image signal generated by the image processing section206onto the projection surface300.

Moreover, in Step S54, the projection-side image transmitting section208transmits the image information provided from the splitter205to the downstream device. When the downstream device is not present, Step S54is omitted.

According to the first projector200aand a control method of the first projector200aaccording to the embodiment, the generating section213generates the resolution information different between the tiling mode and the stack mode. The upstream communication section204transmits the resolution information generated by the generating section213to the PC100. For this reason, it is possible to cause the PC100to generate image information corresponding to a tiling image in the tiling mode and to cause the PC100to generate image information corresponding to a stack image in the stack mode.

The resolution information generated by the generating section213is included in EDID communicated between a so-called sink device and a source device. Therefore, the PC100can be notified of the resolution information corresponding to the tiling mode and the resolution information corresponding to the stack mode without using a new communication form for notifying the PC100as one example of the source device of the resolution information from the first projector200aas one example of the sink device.

The generating section213generates the first resolution information indicating the resolution of a tiling image in the tiling mode, and generates the second resolution information indicating the resolution of a stack image in the stack mode. The upstream communication section204notifies the PC100of the first resolution information in the tiling mode, and notifies the PC100of the second resolution information in the stack mode.

For this reason, the resolution of a tiling image and the resolution of a stack image can be specified for the PC100.

The resolution indicated by the first resolution information is greater than the resolution indicated by the second resolution information. For this reason, the resolution of a tiling image can be greater than the resolution of a stack image.

In the stack mode, the generating section213notifies the PC100of the second resolution information indicating the common resolution. For this reason, it is possible in the stack mode to cause the PC100to provide image information having a resolution that all of the first projector200a, the second projector200b, and the third projector200ccan support. Therefore, for example, even when the supportable resolution is different among the first projector200a, the second projector200b, and the third projector200c, all of the first projector200a, the second projector200b, and the third projector200ccan project an image according to the image information from the PC100.

B: Modified Examples

In the first embodiment, for example configurations exemplified below may be employed.

In the first embodiment, the first projector200a, the second projector200b, and the third projector200cmay execute an edge blending process in the tiling mode. The edge blending process is a process in which in the tiling mode, a plurality of projection images are partially superimposed, and light is reduced at the superimposed portion of the projection images so that the total value of illuminance of the projection images at the superimposed portion is equal to the illuminance of a non-superimposed portion.

In this case, the horizontal resolution, that is, the number of horizontal pixels of a superimposed region is shown in the tiling information, and the generating section213determines, as the horizontal resolution of a tiling image, a horizontal resolution obtained by subtractingthe total value of the horizontal resolutions of the superimposed regions from the horizontal resolution of a tiling image calculated as described above.

In the first embodiment and Modified Example 1, all or a portion of the functions realized by the processing section211by executing the program may be realized by hardware using an electronic circuit such as, for example, a field programmable gate array (FPGA) or an application specific IC (ASIC).

In the first embodiment, Modified Example 1, and Modified Example 2, although the liquid crystal light valve14is used as one example of a light modulator, the light modulator is not limited to a liquid crystal light valve and can be appropriately changed. For example, the light modulator may have a configuration using three reflective liquid crystal panels. Moreover, the light modulator may have a configuration such as of a type using one liquid crystal panel, a type of using three digital mirror devices (DMDs), or a type of using one digital mirror device. When only one liquid crystal panel or DMD is used as the light modulator, members corresponding to the color separating optical system and the color combining optical system are not needed. Moreover, in addition to the liquid crystal panel and the DMD, a configuration in which the light emitted by the light source13can be modulated can be employed as the light modulator.

In the first embodiment and Modified Example 1 to Modified Example 3, the most-upstream projector information, the tiling information, and the cut-out portion information may not be each exchanged between the projectors200, but may be individually set in each of the projectors200by the user.