METHOD OF CONTROLLING PROJECTOR, PROJECTOR, AND NON-TRANSITORY COMPUTER-READABLE STORAGE MEDIUM STORING PROGRAM

A method of controlling a projector includes performing tiling projection in a first area and a second area by a first projector and a first projector group projecting image light beams in the first area and the second projector group projecting image light beams in the second area, performing first adjustment processing of applying a second adjustment amount smaller than a first adjustment amount to the first projector group and projecting the image light beams when projection by the first projector stops and first processing is selected, and performing second adjustment processing of applying a third adjustment amount no larger than a difference between the first adjustment amount and the second adjustment amount to the first projector group after the first adjustment processing, and projecting the image light beams.

The present application is based on, and claims priority from JP Application Serial Number 2022-177590, filed Nov. 4, 2022, the disclosure of which is hereby incorporated by reference herein in its entirety.

BACKGROUND

1. Technical Field

The present disclosure relates to a method of controlling a projector, a projector, and a non-transitory computer-readable storage medium storing a program.

2. Related Art

In the past, there has been known a technology related to stack projection and tiling projection of a plurality of projectors (see, e.g., JP-A-2021-71609 (Document 1)).

In Document 1, there is disclosed the following technology. That is, in a projection system constituted by a plurality of projector groups, there are a first projector group for displaying a first combined image in a first area of a display surface in a stacked manner, and a second projector group for displaying a second combined image in a second area of the display surface in a stacked manner. Apart of the first area overlaps a part of the second area, and the first projector group and the second projector group perform the tiling projection. The luminance of the first projector group and the luminance of the second projector group are each adjusted so that the luminance of the first area and the luminance of the second area approximate to each other.

In Document 1, there is described the point that the control is performed so as to approximate the luminance of an entire area including both of the first area in which the projection is performed by a plurality of projectors and the second area in which the projection is performed by another plurality of projectors between the case of performing the stack projection and the case of performing the tiling projection. When one of the projectors in the projector group cannot perform the projection due to a failure or the like, it is necessary to execute processing of adjusting the luminance. However, there is a possibility that the user recognizes the luminance variation of the projection surface caused during the execution of the processing of adjusting the luminance to cause a feeling of strangeness.

SUMMARY

Δn aspect of the present disclosure is a method of controlling a projector including performing tiling projection in a first area and a second area of a projection surface by projecting image light beams in the first area by a first projector and a first projector group including one or more projectors, and projecting image light beams in the second area by a second projector group including two or more projectors, selecting either one of first processing of adjusting luminance of a light source of the first projector group in two or more times in a first period based on at least one of a luminance variation of an input image and peripheral luminance of the projection surface and second processing of adjusting the luminance of the light source of the first projector group at a time in a second period shorter than the first period when projection by the first projector stops, deciding a first adjustment amount of adjusting output of the light source of the first projector group so that luminance of the first area in which the image light beams of the first projector group are projected coincides with luminance of the second area in which the image light beams of the second projector group are projected when the projection by the first projector stops, performing first adjustment processing of applying a second adjustment amount smaller than the first adjustment amount to the first projector group when the first processing is selected, projecting, by the first projector group, the image light beams after the first adjustment processing, performing second adjustment processing of applying a third adjustment amount which is no larger than a difference between the first adjustment amount and the second adjustment amount to the first projector group after the projecting the image light beams by the first projector group, and projecting, by the first projector group, the image light beams after performing the second adjustment processing.

Another aspect of the present disclosure is a non-transitory computer-readable storage medium storing a program configured to make a processor of a projector execute performing tiling projection in a first area and a second area of a projection surface by projecting image light beams in the first area by a first projector and a first projector group including one or more projectors, and projecting image light beams in the second area by a second projector group including two or more projectors, selecting either one of first processing of adjusting luminance of a light source of the first projector group in two or more times in a first period based on at least one of a luminance variation of an input image and peripheral luminance of the projection surface and second processing of adjusting the luminance of the light source of the first projector group at a time in a second period shorter than the first period when projection by the first projector stops, deciding a first adjustment amount of adjusting output of the light source of the first projector group so that luminance of the first area in which the image light beams of the first projector group are projected coincides with luminance of the second area in which the image light beams of the second projector group are projected when the projection by the first projector stops, performing first adjustment processing of applying a second adjustment amount smaller than the first adjustment amount to the first projector group when the first processing is selected, projecting, by the first projector group, the image light beams after performing the first adjustment processing, performing second adjustment processing of applying a third adjustment amount which is no larger than a difference between the first adjustment amount and the second adjustment amount to the first projector group after the projecting the image light beams by the first projector group, and projecting, by the first projector group, the image light beams after performing the second adjustment processing.

Still another aspect of the present disclosure is a projector including a light source, a memory, and at least one processor, wherein the at least one processor is configured to execute performing tiling projection in a first area and a second area of a projection surface by projecting image light beams in the first area by a first projector and a first projector group including one or more projectors, and projecting image light beams in the second area by a second projector group including two or more projectors, selecting either one of first processing of adjusting luminance of a light source of the first projector group in two or more times in a first period based on at least one of a luminance variation of an input image and peripheral luminance of the projection surface and second processing of adjusting the luminance of the light source of the first projector group at a time in a second period shorter than the first period when projection by the first projector stops, deciding a first adjustment amount of adjusting output of the light source of the first projector group so that luminance of the first area in which the image light beams of the first projector group are projected coincides with luminance of the second area in which the image light beams of the second projector group are projected when the projection by the first projector stops, performing first adjustment processing of applying a second adjustment amount smaller than the first adjustment amount to the first projector group when the first processing is selected, projecting, by the first projector group, the image light beams after performing the first adjustment processing, performing second adjustment processing of applying a third adjustment amount which is no larger than a difference between the first adjustment amount and the second adjustment amount to the first projector group after the projecting the image light beams by the first projector group, and projecting, by the first projector group, the image light beams after performing the second adjustment processing, and the projector is included in either one of the first projector group and the second projector group.

DESCRIPTION OF ΔN EXEMPLARY EMBODIMENT

Δn embodiment will hereinafter be described with reference to the drawings.

FIG.1is a diagram showing an example of a configuration of an image projection system.1according to the present embodiment.

The image projection system1is provided with projectors100and an image supply device200. The projectors100include a first projector100A, a second projector100B, a third projector100C, and a fourth projector100D.

The second projector100B corresponds to an example of a “first projector group.” In the following description, the second projector100B is described as a first projector group GA in some cases for the sake of convenience.

The third projector100C and the fourth projector100D correspond to an example of a “second projector group.” In the following description, the third projector100C and the fourth projector100D are described as a second projector group GB in some cases.

Further, the first projector100A through the fourth projector100D are connected to each other so as to be able to communicate with each other. The first projector100A through the fourth projector100D are connected to each other so as to be able to communicate with each other via, for example, an Ethernet (a registered trademark) cable.

The first projector100A through the fourth projector100D are connected to each other so as to be able to perform wire communication with each other with the Ethernet (the registered trademark) cable or the like in the present embodiment, but can be connected to each other so as to be able to perform wireless communication with each other with Wi-Fi (a registered trademark) or the like.

The image supply device200is formed of, for example, a personal computer, and supplies an image to each of the first projector100A through the fourth projector100D. The image supply device200supplies the image generated by reproducing, for example, a content to each of the first projector100A through the fourth projector100D via the Ethernet (the registered trademark) cable.

The image supply device200is connected to the first projector100A through the fourth projector100D so as to be able to perform the wire communication with each other with the Ethernet (the registered trademark) cable or the like in the present embodiment, but can be connected thereto so as to be able to perform the wireless communication with Wi-Fi (the registered trademark) or the like.

The image supply device200is formed of the personal computer in the present embodiment, but can be formed of a tablet terminal, a smartphone, or the like.

The first projector100A through the fourth projector100D are arranged in, for example, a horizontal direction ofFIG.1. In other words, the first projector100A through the fourth projector100D are arranged along a direction parallel to a screen SC.

The first projector100A projects a first image light beam PLA in a first area AR1of the screen SC. The second projector100B projects a second image light beam PLB in the first area AR1of the screen SC. The third projector100C projects a third image light beam PLC in a second area AR2of the screen SC. The fourth projector100D projects a fourth image light beam PLD in the second area AR2of the screen SC.

Further, the first projector100A and the second projector100B project the first image light beam PLA and the second image light beam PLB so as to form a first image PM1on the screen SC. The third projector100C and the fourth projector100D project the third image light beam PLC and the fourth image light beam PLD so as to form a second image PM2on the screen SC. As shown inFIG.1, the first image PM1and the second image PM2are arranged in the horizontal direction. The first image PM1and the second image PM2form a single projection image P.

The screen SC corresponds to an example of a “projection surface.”

The third area AR3is an area where the first area AR1and the second area AR2overlap each other, and is an area where the first image PM1and the second image PM2are superimposed on each other. On the first image light beam PLA through the fourth image light beam PLD to be projected in the third area AR3, there is performed so-called edge blending processing, and the first image PM1and the second image PM2are smoothly connected to each other.

In the following explanation, the description of image light beam PL is used in some cases when the first image light beam PLA through the fourth image light beam PLD are not distinguished from each other.

In the present embodiment, the first projector100A and the second projector100B perform so-called stacking display of the first image PM1, and the third projector100C and the fourth projector100D perform so-called stacking display of the second image PM2. Further, the first projector100A through the fourth projector100D perform so-called tiling display of the first image PM1and the second image PM2. The stacking display means that, for example, a plurality of projectors projects the same image in a superimposed manner to thereby display that image brighter than when displaying that image with a single projector. The tiling display means that, for example, images are projected side by side using a plurality of projectors to thereby display a larger image than the image displayed with a single projector.

Further, in the present embodiment, for example, the fourth projector100D functions as a primary projector, and the first projector100A through the third projector100C function as secondary projectors. The fourth projector100D controls an operation of each of the first projector100A through the third projector100C. Specifically, as described with reference toFIG.3, the fourth projector100D controls output of a light source111A of each of the first projector100A through the third projector100C.

The light source111A will further be described with reference toFIG.2.

FIG.2is a diagram showing an example of a configuration of the projector100according to the present embodiment.

Since the first projector100A through the fourth projector100D have respective configurations substantially the same as each other, the configuration of the first projector100A will be described with reference toFIG.2, and the description of the configurations of the second projector100B through the fourth projector100D will be omitted. It should be noted that in the following description, the first projector100A through the fourth projector100D are each described as the projector100when the first projector100A through the fourth projector100D are not distinguished from each other.

As shown inFIG.2, the first projector100A is provided with a projection unit110and a driver120for driving the projection unit110. The projection unit110forms an optical image to project the first image light beam PLA on the screen SC. It should be noted that in the present embodiment, the projection unit110projects the first projection image PLA corresponding to image data from the image supply device200on the screen SC.

The projection unit110is provided with a light source unit111, a light modulation device112, and a projection optical system113. The driver120is provided with a light source driver121and a light modulation device driver122.

The light source unit111is provided with a solid-state light source111A such as an LED (Light Emitting Diode) or a laser source.

The solid-state light source111A corresponds to an example of a “light source.”

In the present embodiment, there is described when the light source unit111is provided with the solid-state light source111A, but this is not a limitation. It is possible for the light source unit111to be provided with a lamp light source such as a halogen lamp, a xenon lamp, or an extra high pressure mercury lamp instead of the solid-state light source111A.

In the following description, the solid-state light source111A is described as the light source111A in some cases.

Further, the light source unit111can also be provided with a reflector and an auxiliary reflector for guiding the light emitted by the light source111A to the light modulation device112. Further, the light source unit111can also be provided with a lens group for improving the optical characteristics of the projection light, a polarization plate, a dimming element for reducing the light intensity of the light emitted by the light source111A on a path leading to the light modulation device112, or the like.

The light source driver121is coupled to an internal bus107, and puts the light source111A of the light source unit111on and off in accordance with an instruction of a first controller150coupled likewise to the internal bus107. In the present embodiment, the light source driver121controls the output of the light source111A in accordance with the instructions of a first processing unit155and a second processing unit156of the fourth projector100D described with reference toFIG.3.

The light modulation device112is provided with three liquid crystal panels115corresponding respectively to, for example, the three primary colors of R, G, and B. The character R represents red, the character G represents green, and the character B represents blue. In other words, the light modulation device112is provided with the liquid crystal panel115corresponding to an R colored light beam, the liquid crystal panel115corresponding to a G colored light beam, and the liquid crystal panel115corresponding to a B colored light beam.

The light emitted by the light source unit111is separated into colored light beams of the three colors of RGB, and the colored light beams respectively enter the corresponding liquid crystal panels115. The three liquid crystal panels115are each a transmissive liquid crystal panel, and each modulate the light transmitted therethrough to generate the first image light beam PLA. The first image light beams PLA having been modulated while passing through the respective liquid crystal panels115are combined with each other by a combining optical system such as a cross dichroic prism, and are then emitted to the projection optical system113.

When the light modulation device112is provided with the liquid crystal panels115of the transmissive type as the light modulation elements will be described in the present embodiment, but this is not a limitation. The light modulation element can be a reflective liquid crystal panel, or can also be a digital micromirror device (Digital Micromirror Device).

The light modulation device112is driven by the light modulation device driver122. The light modulation device driver122is coupled to an image processor145.

To the light modulation device driver122, there is input image data corresponding to the respective primary colors of R, G, and B from the image processor145. The light modulation device driver122converts the image data input thereto into data signals suitable for the operations of the liquid crystal panels115. The light modulation device driver122applies a voltage to each pixel of each of the liquid crystal panels115based on the data signal thus converted to thereby draw an image on each of the liquid crystal panels115.

The projection optical system113is provided with a projection lens, a mirror, or the like for focusing the image light beam PLA having entered the projection optical system113on the screen SC. Further, the projection optical system113is provided with a zoom mechanism for expanding or contracting the image to be projected on the screen SC, a focus adjustment mechanism for performing a focus adjustment, a lens shift mechanism for adjusting a projection direction of the image light beam PLA, and so on.

Further, the first projector100A is provided with an illuminance sensor170. The illuminance sensor170detects the luminance around the first projector100A. The illuminance sensor170is arranged at, for example, an opposite side to the side on which the image light beam PLA is projected in a chassis of the first projector100A. In this case, the illuminance sensor170can suppress an influence of the image light beam PLA to the illuminance to be detected.

The illuminance sensor170transmits a signal representing first illuminance BRA thus detected to the first controller150. The first controller150transmits the first illuminance BRA detected by the illuminance sensor170to the fourth projector100D via a first communication interface141.

The first projector100A is further provided with an operator131, a remote control light receiver133, an input interface135, a storage137, the first communication interface141, a frame memory143, the image processor145, and the first controller150. The input interface135, the storage137, the first communication interface141, the image processor145, the first controller150, and the illuminance sensor170are connected to each other so as to be able to achieve data communication with each other via the internal bus107.

The operator131is provided with a variety of buttons and switches disposed on a surface of the chassis of the first projector100A, and generates an operation signal corresponding to an operation to these buttons and switches to output the operation signal to the input interface135. The input interface135is provided with a circuit for outputting the operation signal input from the operator131to the first controller150.

The remote control light receiver133receives an infrared signal transmitted from a remote controller5, and then decodes the infrared signal thus received to generate the operation signal. The remote control light receiver133outputs the operation signal thus generated to the input interface135. The input interface135is provided with a circuit for outputting the operation signal input from the remote control light receiver133to the first controller150.

The storage137is a magnetic recording device such as an HDD (Hard Disk Drive), or a storage device using a semiconductor storage element such as a flash memory or an SSD (Solid State Drive). The storage137stores a program to be executed by the first controller150, data having been processed by the first controller150, the image data, and so on.

The first communication interface141is a communication interface for executing communication with the image supply device200and the second projector100B through the fourth projector100D in compliance with the Ethernet (the registered trademark) standard. The first communication interface141is provided with a connector to which the Ethernet (the registered trademark) cable is coupled, and an interface circuit for processing a signal transmitted through the connector. The first communication interface141is an interface board having the connector and the interface circuit, and is coupled to a main board on which a first processor150A and so on of the first controller150are mounted. Alternatively, the connector and the interface circuit constituting the first communication interface141are mounted on the main board of the first controller150. The first communication interface141receives the image data and so on from the image supply device200. Further, the first communication interface141transmits first illuminance BRA detected by the illuminance sensor170to the fourth projector100D, and receives instruction information of the output of the light source111A from the fourth projector100D.

The first controller150is provided with a first memory150B and the first processor150A. The first memory150B is a storage device for storing programs to be executed by the first processor150A and data in a nonvolatile manner. The first memory150B is formed of a magnetic storage device, a semiconductor storage element such as a flash ROM (Read Only Memory), or a nonvolatile storage device of other types. Further, the first memory150B can also include a RAM (Random Access Memory) constituting a work area for the first processor150A. The first memory150B stores data to be processed by the first controller150, and a first control program PGM1or the like to be executed by the first processor150A.

The first processor150A can be constituted by a single processor, or it is also possible to adopt a configuration in which a plurality of processors functions as the first processor150A. The first processor150A executes the first control program PGM1to control each part of the first projector100A. For example, an execution instruction of the image processing corresponding to the operation received by the operator131or the remote controller5, and parameters to be used in the image processing are output by the first processor150A to the image processor145. The parameters include, for example, geometric correction parameters for correcting a geometric distortion of the image to be projected on the screen SC. Further, the first processor150A controls the light source driver121to control lighting and extinction of the light source unit111, and to adjust the output, namely the light intensity, of the light source unit111.

The first processor150A corresponds to an example of “at least one processor.” The first memory150B corresponds to an example of a “memory.”

The first control program PGM1corresponds to an example of a “program.”

The first processor150A can also be formed of an SoC (system on Chip) integrated with a part or the whole of the first memory150B and other circuits. Further, the first processor150A can also be formed of a combination of a CPU (Central Processing Unit) for executing the program and a DSP (Digital Signal Processor) for executing predetermined arithmetic processing. It is also possible to adopt a configuration in which all of the functions of the first processor150A are implemented in the hardware, or it is also possible to configure all of the functions of the first processor150A using a programmable device.

The image processor145and the frame memory143can be formed of, for example, an integrated circuit. The integrated circuit includes an LSI Large-Scale Integration), an ASIC (Application Specific Integrated Circuit), and a PLD (Programmable Logic Device). The PLD includes, for example, an FPGA (Field-Programmable Gate Array). Further, it is also possible for an analog circuit to be included as a part of a configuration of the integrated circuit, or it is also possible to adopt a combination of the processor and the integrated circuit. The combination of the processor and the integrated circuit is called a micro-controller (MCU), an SoC (System-on-a-chip), a system LSI, a chip set, and so on.

The image processor145develops the image data input from the first communication interface141to the image processor145in the frame memory143. The frame memory143is provided with a plurality of banks. Each of the banks has a storage capacity sufficient for the image data corresponding to one frame to be written therein. The frame memory143is formed of, for example, an SDRAM (Synchronous Dynamic Random Access Memory).

The image processor145performs image processing such as resolution conversion processing, resizing processing, a correction of a distortion aberration, shape correction processing, digital zoom processing, and an adjustment of tint and luminance of the image on the image data developed in the frame memory143.

Further, the image processor145converts an input frame frequency of a vertical sync signal into a drawing frequency to generate a vertical sync signal. The vertical sync signal thus generated is referred to as an output sync signal. The image processor145outputs the output sync signal thus generated to the light modulation device driver122.

Then, a configuration of the first controller150of the fourth projector100D will be described with reference toFIG.3.FIG.3is a diagram showing an example of the configuration of the first controller150of the fourth projector100D. The first controller150of the fourth projector100D instructs the output of the light sources111A of the first projector100A through the third projector100C, and at the same time, controls the operation of the fourth projector100D.

As shown inFIG.3, the first controller150is provided with a projection instructor151, a stoppage detector152, a selector153, a decider154, the first processing unit155, the second processing unit156, and an image storage157. Specifically, the first processor150A of the first controller150executes the first control program PGM1stored in the first memory150B to thereby function as the projection instructor151, the stoppage detector152, the selector153, the decider154, the first processing unit155, and the second processing unit156. Further, the first processor150A of the first controller150executes the first control program PGM1stored in the first memory150B to thereby make the first memory150B function as the image storage157.

The image storage157stores the first image PM1from a second frame FR2to a first frame FR1. The first frame FR1is a frame of the first image PM1which is input to the first projector100A when the stoppage detector152has detected that the projection by the first projector100A has stopped. The second frame FR2is a frame of the first image PM1a predetermined number N of frames before the first frame FR1. The predetermined number N is, for example, 10. The first image PM1from the second frame FR2to the first frame FR1is stored in the image storage157by the stoppage detector152.

The projection instructor151makes the first projector100A project the first image light beam PLA corresponding to the first image PM1in the first area AR1of the screen SC. Further, the projection instructor151makes the second projector100B project the second image light beam PLB corresponding to the first image PM1in the first area AR1of the screen SC. Further, the projection instructor151makes the third projector100C project the third image light beam PLC corresponding to the second image PM2in the second area AR2of the screen SC.

Further, the projection instructor151makes the liquid crystal panel115of the fourth projector100D display the second image PM2, and makes the projection unit110of the fourth projector100D project the fourth image light beam PLD corresponding to the second image PM2in the second area AR2of the screen SC.

In other words, the projection instructor151makes the first projector100A and the second projector100B project the first image PM1in the first area AR1of the screen SC. Further, the projection instructor151makes the third projector100C and the fourth projector100D project the second image PM2in the second area AR2of the screen SC. In this way, the projection instructor151makes the first projector100A through the fourth projector100D project the first image PM1and the second image PM2in the first area AR1and the second area AR2.

The stoppage detector152detects that the projection by the first projector100A has stopped. When the projection by the first projector100A has stopped, for example, the first controller150of the first projector100A transmits stoppage information representing the fact that the projection by the first projector100A has stopped to the fourth projector100D. The stoppage detector152receives the stoppage information from the first projector100A to thereby detect that the projection by the first projector100A has stopped.

Further, when the stoppage detector152has detected the fact that the projection by the first projector100A has stopped, the stoppage detector152stores the first image PM1from the second frame FR2to the first frame FR1in the image storage157.

For example, the stoppage detector152stores the predetermined number N of frames of the first image PM1in the image storage157. Further, every time the frame of the first image PM1to be projected by the first projector100A is updated, the stoppage detector152updates the oldest one of the predetermined number N of frames of the first image PM1stored in the image storage157with the latest one. Further, when the stoppage detector152has detected that the projection by the first projector100A has stopped, the stoppage detector152stops the updating processing described above. The fact that the projection has stopped means a state in which the projection of the projection light is not performed due to a trouble of, for example, the projection unit110, the driver120, or the first controller150. The fact that the projection has stopped means when the light source unit111has stopped emitting light due to, for example, a failure.

When the stoppage detector152has detected the fact that the projection by the first projector100A has stopped, the selector153selects either one of first processing PR1and second processing PR2based on a luminance variation ΔBR of the first image PM1as an input image. The first processing PR1is processing of adjusting the luminance of the light source111A of the first projector group GA, namely the second projector100B, in a stepwise manner in two or more times in a first period PE1. The second processing PR2is processing of adjusting the luminance of the light source111A of the first projector group GA, namely the second projector100B, in a stepwise manner at a time in a second period PE2shorter than the first period PE1.

The first period PE1is, for example, 200 msec. The second period PE2is, for example, 50 msec.

The luminance variation ΔBR is a difference between an average pixel value V1of the first frame FR1of the first image PM1as the input image and an average pixel value V2of the second frame FR2prior to the first frame FR1. The first frame FR1is a frame of the first image PM1which is input to the second projector100B when the stoppage detector152has detected that the projection by the first projector100A has stopped. The second frame FR2is a frame the predetermined number N of frames before the first frame FR1. The predetermined number N is, for example, 10.

When the luminance variation ΔBR is lower than a first threshold value TH1, the selector153selects the first processing PR1. Further, when the luminance variation ΔBR is no lower than the first threshold value TH1, the selector153selects the second processing PR2. The first threshold value TH1is, for example, 20% of a maximum value of the luminance variation ΔBR. The maximum value of the luminance variation ΔBR means the luminance variation ΔBR when the second frame FR2is a black solid image, and the first frame FR1is a white solid image.

The decider154decides a first adjustment amount AD1of adjusting the output of the light source111A of the first projector group GA, namely the second projector100B, so that the luminance of the first area AR1coincides with the luminance of the second area AR2. The luminance of the first area AR1represents the luminance of the first area AR1in which the image light beam of the first projector group GA is projected. The luminance of the second area AR2represents the luminance of the second area AR2in which the image light beam of the second projector group GB, namely the third projector100C and the fourth projector100D, is projected.

Further, the decider154executes the following processing when it is unachievable to make the luminance of the first area AR1and the luminance of the second area AR2coincide with each other only by adjusting the output of the light source111A of, for example, the first projector group GA. That is, the decider154decides a fourth adjustment amount AD4of adjusting the output of the light source111A of the second projector group GB so as to fulfill the following condition.

Condition: The luminance of the second area AR2when projecting the image light beam with the fourth adjustment amount AD4applied to the second projector group GB coincides with the luminance of the first area AR1when projecting the image light beam with the first adjustment amount AD1applied to the first projector group GA.

When the selector153has selected the first processing PR1, the first processing unit155performs first adjustment processing PR11and second adjustment processing PR12as the first processing PR1to project the image light beam. The first adjustment processing PR11is processing of applying a second adjustment amount AD2smaller than the first adjustment amount AD1to the first projector group GA. The second adjustment processing PR12is processing of applying a third adjustment amount AD3no larger than a difference between the first adjustment amount AD1and the second adjustment amount AD2to the first projector group GA after the first adjustment processing PR11.

In the present embodiment, there will be described when the third adjustment amount AD3coincides with the difference between the first adjustment amount AD1and the second adjustment amount AD2. In other words, there will be described when the first processing unit155adjusts the luminance of the light source111A of the first projector group GA in two steps in the first period PE1as the first processing PR1.

For example, the first processing unit155projects the image light beam while applying the second adjustment amount AD2to the first projector group GA at a first time point T1in the first period PE1. Further, the first processing unit155projects the image light beam while applying the third adjustment amount AD3to the first projector group GA at a second time point T2subsequent to the first time point T1in the first period PE1.

The first processing PR1in this case will further be described with reference toFIG.4.

The first processing unit155executes the following processing when it is unachievable to make the luminance of the first area AR1and the luminance of the second area AR2coincide with each other only by adjusting the output of the light source111A of, for example, the first projector group GA. In other words, the first processing unit155projects the image light beam while applying a fifth adjustment amount AD5smaller than the fourth adjustment amount AD4to the second projector group GB as the first adjustment processing PR11. Further, the first processing unit155projects the image light beam while applying a sixth adjustment amount AD6no larger than a difference between the fourth adjustment amount AD4and the fifth adjustment amount AD5to the second projector group GB as the second adjustment processing PR12.

In the present embodiment, there will be described when the sixth adjustment amount AD6coincides with the difference between the fourth adjustment amount AD4and the fifth adjustment amount AD5. In other words, there will be described when the first processing unit155adjusts the luminance of the light source111A of the second projector group GB in two steps in the first period PE1as the first processing PR1.

For example, at the first time point T1in the first period PE1, the first processing unit155projects the image light beam while applying the second adjustment amount AD2to the first projector group GA, and projects the image light beam while applying the fifth adjustment amount AD5to the second projector group GB. Further, at the second time point T2subsequent to the first time point T1in the first period PE1, the first processing unit155projects the image light beam while applying the third adjustment amount AD3to the first projector group GA, and projects the image light beam while applying the sixth adjustment amount AD6to the second projector group GB.

The first processing PR1in this case will further be described with reference toFIG.5.

When the selector153has selected the second processing PR2, the second processing unit156projects the image light beam while applying the first adjustment amount AD1to the first projector group GA.

For example, the second processing unit156projects the image light beam while applying the first adjustment amount AD1to the first projector group GA in the second period PE2shorter than the first period PE1.

The second processing PR2in this case will further be described with reference toFIG.4.

The second processing unit156executes the following processing when it is unachievable to make the luminance of the first area AR1and the luminance of the second area AR2coincide with each other only by adjusting the output of the light source111A of, for example, the first projector group GA. The first processing unit155projects the image light beam while applying the first adjustment amount AD1to the first projector group GA, and projects the image light beam while applying the fourth adjustment amount AD4to the second projector group GB.

The second processing PR2in this case will further be described with reference toFIG.5.

Then, there will be described when the first processing unit155and the second processing unit156adjust only the first projector group GA with reference toFIG.4.

FIG.4is a graph showing an example of the first processing PR1and the second processing PR2. InFIG.4, the horizontal axis represents time T, and the vertical axis represents luminance EA of the first area AR1.

There will be described when the output of the light source111A of each of the first projector100A through the fourth projector100D is 50% before the projection by the first projector100A stops. In this case, the luminance of the first area AR1and the second area AR2is, for example, 100%. It should be noted that the luminance EA of the first area AR1is described as a sum of the output of the light source111A of the first projector100A and the output of the light source111A of the second projector100B. Further, the luminance of the second area AR2is described as a sum of the output of the light source111A of the third projector100C and the output of the light source111A of the fourth projector100D.

As shown inFIG.4, the projection by the first projector100A stops at a time point TA. As a result, as shown in the graph GC, the luminance EA of the first area AR1decreases from second luminance ET12to first luminance ET11. The second luminance ET12is 100%, and the first luminance ET11is 50%.

The decider154decides the first adjustment amount AD1as an increase by 50%. First, there will be described when the selector153has selected the first processing PR1.

As represented by the graph G11, the first processing unit155projects the image light beam while applying the second adjustment amount AD2to the first projector group GA at the first time point T1in the first period PE1. The first period PE1is a period from the time point TA to a time point TE1. The first period PE1is, for example, 300 msec. The first time point T1represents a time point when, for example, 50 msec elapses from the time point TA. The second adjustment amount AD2is, for example, an increase by 30%. Specifically, the first processing unit155adjusts the output of the light source111A of the second projector100B from 50% to 80% at the first time point T1.

Then, as represented by the graph G11, the first processing unit155projects the image light beam while applying the third adjustment amount AD3to the first projector group GA at the second time point T2in the first period PE′. The second time point T2represents a time point when, for example, 200 msec elapses from the time point TA. The third adjustment amount AD3is, for example, an increase by 20%. It should be noted that the third adjustment amount AD3is the difference between the first adjustment amount AD1and the second adjustment amount AD2. Specifically, the first processing unit155adjusts the output of the light source111A of the second projector100B from 80% to 100% at the second time point T2.

As a result, the luminance EA of the first area AR1becomes the second luminance ET12by being adjusted in a stepwise manner in two or more times. Specifically, the luminance EA of the first area AR1coincides with the luminance of the second area AR2.

Then, there will be described when the selector153has selected the second processing PR2. As represented by the graph G12, the second processing unit156projects the image light beam while applying the first adjustment amount AD1to the first projector group GA at the first time point T1in the second period PE2. The first adjustment amount AD1is an increase by 50%. Specifically, the second processing unit156adjusts the output of the light source111A of the second projector100B from 50% to 100% at a time at the first time point T1.

As a result, the luminance EA of the first area AR1becomes the second luminance ET12. Specifically, the luminance EA of the first area AR1coincides with the luminance of the second area AR2.

As described with reference toFIG.4, in the second processing PR2, the output of the light source111A of the first projector group GA is adjusted at a time in the second period PE2. In contrast, in the first processing PR1, the output of the light source111A of the first projector group GA is adjusted in a stepwise manner in the first period PE1longer than the second period PE2. Therefore, by executing the first processing PR1, it is possible to decrease the possibility that the user has a feeling of strangeness during the execution of the processing of adjusting the luminance compared to when executing the second processing PR2.

Further, although there is described when adjusting the output of the light source111A of the first projector group GA in two steps in the first processing PR1inFIG.4, but this is not a limitation. It is also possible to adjust the output of the light source111A of the first projector group GA in three or more steps in the first processing PR1.

Further, it is preferable that the smaller the luminance variation ΔBR is, the more the number of steps in which the output of the light source111A of the first projector group GA is adjusted increases. In this case, it is possible to decrease the possibility that the user has a feeling of strangeness during the execution of the processing of adjusting the luminance.

Then, there will be described when the first processing unit155and the second processing unit156adjust the first projector group GA and the second projector group GB with reference toFIG.5.

FIG.5is a graph showing another example of the first processing PR1and the second processing PR2. InFIG.5, the horizontal axis represents time T, and the vertical axis represents luminance EA of the first area AR1and the luminance EB of the second area AR2.

There will be described when the output of the light source111A of each of the first projector100A through the fourth projector100D is 70% before the projection by the first projector100A stops. In this case, the luminance of the first area AR1and the second area AR2is, for example, 140%. It should be noted that the luminance EA of the first area AR1is described as the sum of the output of the light source111A of the first projector100A and the output of the light source111A of the second projector100B. Further, the luminance EB of the second area AR2is described as the sum of the output of the light source111A of the third projector100C and the output of the light source111A of the fourth projector100D.

As shown inFIG.5, the projection by the first projector100A stops at the time point TA. As a result, as shown in the graph GC, the luminance EA of the first area AR1decreases from the second luminance ET12to the first luminance ET11. The second luminance ET12is 140%, and the first luminance ET11is 70%.

The decider154decides the first adjustment amount AD1as an increase by 30%. First, there will be described when the selector153has selected the first processing PR1.

As represented by the graph G21, the first processing unit155projects the image light beam while applying the second adjustment amount AD2to the first projector group GA at the first time point T1in the first period PE1. The first period PE1is the period from the time point TA to the time point TE1. The first period PE1is, for example, 300 msec. The first time point T1represents a time point when, for example, 50 msec elapses from the time point TA. The second adjustment amount AD2is, for example, an increase by 20%. Specifically, the first processing unit155adjusts the output of the light source111A of the second projector100B from 70% to 90% at the first time point T1.

Further, as represented by the graph G31, the first processing unit155projects the image light beam while applying the fifth adjustment amount AD5to the second projector group GB at the first time point T1in the first period PE1. The fifth adjustment amount AD5is, for example, a decrease by 10%. Specifically, the first processing unit155adjusts the output of the light source111A of each of the third projector100C and the fourth projector100D from 70% to 60% at the first time point T1. As a result, the luminance EB of the second area AR2decreases from first luminance ET21, namely 140%, to 120%.

Then, as represented by the graph G21, the first processing unit155projects the image light beam while applying the third adjustment amount AD3to the first projector group GA at the second time point T2in the first period PE1. The second time point T2represents a time point when, for example, 200 msec elapses from the time point TA. The third adjustment amount AD3is, for example, an increase by 10%. It should be noted that the third adjustment amount AD3is the difference between the first adjustment amount AD1and the second adjustment amount AD2. Specifically, the first processing unit155adjusts the output of the light source111A of the second projector100B from 90% to third luminance ET13, namely 100%, at the second time point T2.

Further, as represented by the graph G31, the first processing unit155projects the image light beam while applying the sixth adjustment amount AD6to the second projector group GB at the first time point T1in the first period PE1. The sixth adjustment amount AD6is, for example, a decrease by 10%. Specifically, the first processing unit155adjusts the output of the light source111A of each of the third projector100C and the fourth projector100D from 60% to 50% at the first time point T1. As a result, the luminance EB of the second area AR2decreases from 120% to second luminance ET22, namely 100%.

As a result, the luminance EA of the first area AR1coincides with the luminance EB of the second area AR2.

Then, there will be described when the selector153has selected the second processing PR2. As represented by the graph G22, the second processing unit156projects the image light beam while applying the first adjustment amount AD1to the first projector group GA at the first time point T1in the second period PE2. The first adjustment amount AD1is an increase by 30%. Specifically, the second processing unit156adjusts the output of the light source111A of the second projector100B from 70% to 100% at the first time point T1.

Further, as represented by the graph G32, the second processing unit156projects the image light beam while applying the fourth adjustment amount AD4to the second projector group GB at the first time point T1in the second period PE2. The fourth adjustment amount AD4is a decrease by 40%. Specifically, the second processing unit156adjusts the output of the light source111A of the second projector group GB from 140% to 100% at the first time point T1.

As a result, the luminance EA of the first area AR1coincides with the luminance EB of the second area AR2.

As described with reference toFIG.5, in the second processing PR2, the output of the light source111A of each of the first projector group GA and the second projector group GB is adjusted in a stepwise manner in the second period PE2. In contrast, in the first processing PR1, the output of the light source111A of each of the first projector group GA and the second projector group GB is adjusted in a stepwise manner in the first period PE1longer than the second period PE2. Therefore, by executing the first processing PR1, it is possible to decrease the possibility that the user has a feeling of strangeness during the execution of the processing of adjusting the luminance compared to when executing the second processing PR2.

Further, although there is described when adjusting the output of the light source111A of each of the first projector group GA and the second projector group GB in two steps, namely in twice, in the first processing PR1inFIG.5, but this is not a limitation. It is also possible to adjust the output of the light source111A of each of the first projector group GA and the second projector group GB in three or more steps, namely in three or more times, in the first processing PR1.

Further, it is preferable that the smaller the luminance variation ΔBR is, the more the number of steps, namely the number of times, in which the output of the light source111A of each of the first projector group GA and the second projector group GB is adjusted increases. In this case, it is possible to decrease the possibility that the user has a feeling of strangeness during the execution of the processing of adjusting the luminance.

Then, processing of the first controller150of the fourth projector100D will be described with reference toFIG.6throughFIG.8. It should be noted that inFIG.6throughFIG.8, there will be described when the decider154decides the first adjustment amount AD1and the fourth adjustment amount AD4. In other words, there will be described when adjusting the output of the light source111A of the first projector group GA and the output of the light source111A of the second projector group GB.

FIG.6is a flowchart showing an example of the processing of the first controller150of the fourth projector100D.

As shown inFIG.6, first, in the step S101, the projection instructor151makes the first projector100A and the second projector100B project the image light beams corresponding to the first image PM1in the first area AR1of the screen SC.

Then, in the step S103, the projection instructor151makes the third projector100C and the fourth projector100D project the image light beams corresponding to the second image PM2in the second area AR2of the screen SC.

Then, in the step S105, the stoppage detector152determines whether or not the projection by the first projector100A has stopped.

When the stoppage detector152has determined that the projection by the first projector100A has not stopped (NO in the step S105), the process returns to the step S101. When the stoppage detector152has determined that the projection by the first projector100A has stopped (YES in the step S105), the process proceeds to the step S107.

Then, in the step S107, the decider154decides the first adjustment amount AD1. Then, in the step S109, the decider154decides the fourth adjustment amount AD4. It should be noted that in the step S107and the step S109, the decider154decides the first adjustment amount AD1and the fourth adjustment AD4so as to fulfill the following condition.

Condition: The luminance of the second area AR2when projecting the image light beam with the fourth control amount AD4applied to the second projector group GB coincides with the luminance of the first area AR1when projecting the image light beam with the first control amount AD1applied to the first projector group GA.

Then, in the step S111, the selector153executes the selection processing. The “selection processing” means processing of selecting one of the first processing PR1and the second processing PR2. The “selection processing” will be described with reference toFIG.7andFIG.8.

In the step S113, the first controller150determines whether or not the selector153selects the first processing PR1.

When the first controller150has determined that the selector153does not select the first processing PR1(NO in the step S113), the process proceeds to the step S115.

Then, in the step S115, the first controller150determines that the selector153has selected the second processing PR2.

Then, in the step S117, at the first time point T1, the second processing unit156projects the image light beam while applying the first adjustment amount AD1to the first projector group GA, and projects the image light beam while applying the fourth adjustment amount AD4to the second projector group GB. Subsequently, the process is terminated.

When the first controller150has determined that the selector153has selected the first processing PR1(YES in the step S113), the process proceeds to the step S119.

Then, in the step S119, at the first time point T1, the first processing unit155projects the image light beam while applying the second adjustment amount AD2to the first projector group GA, and projects the image light beam while applying the fifth adjustment amount AD5to the second projector group GB.

Then, in the step S121, at the second time point T2, the first processing unit155projects the image light beam while applying the third adjustment amount AD3to the first projector group GA, and projects the image light beam while applying the sixth adjustment amount AD6to the second projector group GB. Subsequently, the process is terminated.

Then, the selection processing when the selector153selects one of the first processing PR1and the second processing PR2based on the luminance variation ΔBR will be described with reference toFIG.7. It should be noted that in the following description, there will be explained when the image storage157stores the first image PM1from the second frame FR2to the first frame FR1.

The first frame FR1is the frame of the first image PM1which is input to the first projector100A when the projection by the first projector100A has stopped. The second frame FR2is the frame of the first image PM1the predetermined number N of frames before the first frame FR1. The predetermined number N is, for example, 10.

FIG.7is a flowchart showing an example of the selection processing to be executed in the step S111shown inFIG.6.

As shown inFIG.7, first, in the step S201, the selector153calculates the average pixel value V1of the first frame FR1of the first image PM1as the input image.

Then, in the step S203, the selector153calculates the average pixel value V2of the second frame FR2of the first image PM1as the input image.

Then, in the step S205, the selector153determines whether or not the luminance variation ΔBR is lower than the first threshold value TH1. The luminance variation ΔBR is the difference between the average pixel value V1and the average pixel value V2. The first threshold value TH1is, for example, 20% of the maximum value of the luminance variation ΔBR. When the selector153has determined that the luminance variation ΔBR is lower than the first threshold value TH1(YES in the step S205), the process proceeds to the step S207.

Then, in the step S207, the selector153selects the first processing PR1. Subsequently, the process returns to the step S113shown inFIG.6.

When the selector153has determined that the luminance variation ΔBR is no lower than the first threshold value TH1(NO in the step S205), the process proceeds to the step S209.

Then, in the step S209, the selector153selects the second processing PR2. Subsequently, the process returns to the step S113shown inFIG.6.

As described with reference toFIG.7, the selector153selects one of the first processing PR1and the second processing PR2based on the luminance variation ΔBR. Therefore, it is possible to appropriately select one of the first processing PR1and the second processing PR2.

In the present embodiment, there is described when the luminance variation ΔBR is the difference between the average pixel value V1of the first frame FR1of the input image and the average pixel value V2of the second frame FR2prior to the first frame FR1, but this is not a limitation. For example, it is possible to calculate absolute values of the differences between the average pixel values between the frames adjacent to each other in a period from the second frame FR2to the first frame FR1, and calculate the average value thereof as the luminance variation ΔBR. In this case, it is possible to appropriately select one of the first processing PR1and the second processing PR2.

Then, the selection processing when the selector153selects one of the first processing PR1and the second processing PR2based on peripheral luminance BRS of the screen SC will be described with reference toFIG.8.FIG.8is a flowchart showing another example of the selection processing to be executed in the step S111shown inFIG.6.

As shown inFIG.8, first, in the step S301, the selector153obtains the first illuminance BRA, second illuminance BRB, third illuminance BRC, and fourth illuminance BRD when the projection by the first projection has stopped.

The first illuminance BRA is illuminance detected by the illuminance sensor170of the first projector100A. The second illuminance BRB is illuminance detected by the illuminance sensor170of the second projector100B. The third illuminance BRC is illuminance detected by the illuminance sensor170of the third projector100C. The fourth illuminance BRD is illuminance detected by the illuminance sensor170of the fourth projector100D.

Then, in the step S303, the selector153calculates the average value of the first illuminance BRA through the fourth illuminance BRD as the peripheral luminance BRS of the screen SC.

Then, in the step S305, the selector153determines whether or not the peripheral luminance of the screen SC is lower than a second threshold value TH2. The second threshold value TH2is, for example, 30 1×.

When it has been determined that the peripheral luminance BRS of the screen SC is lower than the second threshold value TH2(YES in the step S305), the process proceeds to the step S307.

Then, in the step S307, the selector153selects the first processing PR1. Subsequently, the process returns to the step S113shown inFIG.6.

When it has been determined that the peripheral luminance BRS of the screen SC is no lower than the second threshold value TH2(NO in the step S305), the process proceeds to the step S309.

Then, in the step S309, the selector153selects the second processing PR2. Subsequently, the process returns to the step S113shown inFIG.6.

As described with reference toFIG.8, the selector153selects one of the first processing PR1and the second processing PR2based on the peripheral luminance BRS of the screen SC. Therefore, it is possible to appropriately select one of the first processing PR1and the second processing PR2.

In the present embodiment, there is described when the selector153calculates the average value of the first illuminance BRA through the fourth illuminance BRD as the peripheral luminance BRS of the screen SC, but this is not a limitation. It is sufficient for the selector153to calculate the peripheral luminance BRS of the screen SC based on at least one of the first illuminance BRA through the fourth illuminance BRD. For example, it is possible for the selector153to calculate the lowest one of the first illuminance BRA through the fourth illuminance BRD as the peripheral luminance BRS of the screen SC.

Functions and Advantages of Present Embodiment

As described hereinabove with reference toFIG.1throughFIG.8, the method of controlling the projector100according to the present embodiment includes performing the tiling projection in the first area AR1and the second area AR2of the screen SC by projecting the image light beams in the first area AR1by the first projector100A and the first projector group GA including one or more projectors, and projecting the image light beams in the second area AR2by the second projector group GB including two or more projectors, selecting one of the first processing PR1of adjusting the luminance of the light source111A of the first projector group GA in a plurality of times in the first period PE1and the second processing PR2of adjusting the luminance of the light source111A of the first projector group GA at a time in the second period PE2shorter than the first period PR1based on at least one of the luminance variation ΔBR of the input image and the peripheral luminance BRS of the screen SC when the projection by the first projector100A has stopped, deciding the first adjustment amount AD1of adjusting the output of the light source111A of the first projector group GA so that the luminance of the first area AR1in which the image light beam of the first projector group GA is projected coincides with the luminance of the second area AR2in which the image light beam of the second projector group GB is projected, performing the first adjustment processing PR11of applying the second adjustment amount AD2smaller than the first adjustment amount AD1to the first projector group GA when the first processing PR1is selected, projecting, by the first projector group GA, the image light beam after performing the first adjustment processing PR11, performing the second adjustment processing PR12of applying the third adjustment amount AD3no larger than the difference between the first adjustment amount AD1and the second adjustment amount AD2to the first projector group GA after the projecting the image light beam by the first projector group GA, and projecting, by the first projector group GA, the image light beam after performing the second adjustment processing PR12.

Specifically, the method of controlling the projector100according to the present embodiment includes performing the first adjustment processing PR11of applying the second adjustment amount AD2smaller than the first adjustment amount AD1to the first projector group GA when the projection by the first projector100A has stopped and the first processing PR1has been selected, projecting, by the first projector group GA, the image light beam after performing the first adjustment processing PR11, performing the second adjustment processing PR12of applying the third adjustment amount AD3no larger than the difference between the first adjustment amount AD1and the second adjustment amount AD2to the first projector group GA after the projecting the image light beam by the first projector group GA, and projecting, by the first projector group GA, the image light beam after performing the second adjustment processing PR12.

In other words, compared to when executing the second processing PR2of performing the adjustment at a time in the second period PE2shorter than the first period PE1, in the first processing PR1, the luminance of the first projector group GA is adjusted in two or more times in the first period PE1. Therefore, compared to when executing the second processing PR2, in the first processing PR1, it is possible to prevent the user from having a feeling of strangeness during the execution of the adjustment processing of the luminance of the first projector group GA. Therefore, when the projection by the first projector100A stops, it is possible to prevent the user from having a feeling of strangeness during the execution of the processing of adjusting the luminance of the first projector group GA.

Further, the method of controlling the projector100includes deciding the fourth adjustment amount AD4of adjusting the output of the light source111A of the second projector group GB when the first processing PR1is selected, and the first processing PR1includes applying the fifth adjustment amount AD5smaller than the fourth adjustment amount AD4to the second projector group GB, projecting the image light beam by the second projector group GB after applying the fifth adjustment amount AD5to the second projector group GB, applying the sixth adjustment amount AD6no larger than the difference between the fourth adjustment amount AD4and the fifth adjustment amount AD5to the second projector group GB, and projecting the image light beam by the second projector group GB after applying the sixth adjustment amount AD6to the second projector group GB.

In other words, compared to when executing the second processing PR2of performing the adjustment at a time in the second period PE2shorter than the first period PE1, in the first processing PR1, the luminance of the second projector group GB is adjusted in two or more times in the first period PE′. Therefore, compared to when executing the second processing PR2, in the first processing PR1, it is possible to prevent the user from having a feeling of strangeness during the execution of the processing of adjusting the luminance of the second projector group GB. Therefore, when the projection by the first projector100A stops, it is possible to prevent the user from having a feeling of strangeness during the execution of the processing of adjusting the luminance of the second projector group GB.

Further, in the method of controlling the projector100, the first processing PR1includes applying the second adjustment amount AD2to the first projector group GA at the first time point T1in the first period PE1, projecting the image light beam by the first projector group GA after applying the second adjustment amount AD2to the first projector group GA, applying the fifth adjustment amount AD5to the second projector group GB, projecting the image light beam by the second projector group GB after applying the fifth adjustment amount AD5to the second projector group GB, applying the third adjustment amount AD3to the first projector group GA at the second time point T2subsequent to the first time point T1in the first period PE1, projecting the image light beam by the first projector group GA after applying the third adjustment amount AD3to the first projector group GA, applying the sixth adjustment amount AD6to the second projector group GB at the second time point T2, and projecting the image light beam by the second projector group GB after applying the sixth adjustment amount AD6to the second projector group GB.

Therefore, it is possible to adjust the luminance of each of the first projector group GA and the second projector group GB at the same time at the first time point T1and the second time point T2in the first period PE′. Therefore, it is possible to prevent the user from having a feeling of strangeness during the execution of the processing of adjusting the luminance of each of the first projector group GA and the second projector group GB.

Further, the method of controlling the projector100includes applying the first adjustment amount AD1to the first projector group GA when the second processing PR2has been selected, and projecting the image light beam by the first projector group GA after applying the first adjustment amount AD1to the first projector group GA.

Therefore, when executing the second processing PR2, it is possible to adjust the luminance of the first projector group GA in a shorter time and with simpler processing compared to when executing the first processing PR1.

Further, the method of controlling the projector100includes deciding the fourth adjustment amount AD4of adjusting the output of the light source111A of the second projector group GB when the second processing PR2is selected, and the second processing PR2includes applying the first adjustment amount AD1to the first projector group GA in the second period PE2, projecting the image light beam by the first projector group GA after applying the first adjustment amount AD1to the first projector group GA, applying the fourth adjustment amount AD4to the second projector group GB in the second period PE2, and projecting the image light beam by the second projector group GB after applying the fourth adjustment amount AD4to the second projector group GB.

Therefore, when executing the second processing PR2, it is possible to adjust the luminance of each of the first projector group GA and the second projector group GB in a shorter time and with simpler processing compared to when executing the first processing PR1.

Further, in the method of controlling the projector100, deciding the fourth adjustment amount AD4includes deciding the fourth adjustment amount AD4so that the luminance of the second area AR2when the second projector group GB projects the image light beam after applying the fourth adjustment amount AD4to the second projector group GB coincides with the luminance of the first area AR1when the first projector group GA projects the image light beam after applying the first adjustment amount AD1to the first projector group GA.

Therefore, it is possible to make the luminance of the second area AR2coincide with the luminance of the first area AR1. Therefore, it is possible to decide the fourth adjustment amount AD4to an appropriate value.

Further, in the method of controlling the projector100, selecting either one of the first processing PR1and the second processing PR2includes selecting the first processing PR1when the luminance variation ΔBR as the difference between the average pixel value V1of the first frame FR1of the input image input to the first projector group GA and the average pixel value V2of the second frame FR2subsequent to the first frame FR1when the projection by the first projector100A stops is lower than the first threshold value TH1, and selecting the second processing PR2when the luminance variation ΔBR when the projection by the first projector100A stops is no lower than the first threshold value TH1.

Therefore, since the first processing PR1is selected when the luminance variation ΔBR is lower than the first threshold value TH1, and the second processing PR2is selected when the luminance variation ΔBR is no lower than the first threshold value TH1, by appropriately setting the first threshold value TH1, it is possible to appropriately select either one of the first processing PR1and the second processing PR2.

Further, in the method of controlling the projector100, selecting either one of the first processing PR1and the second processing PR2includes selecting the first processing PR1when the peripheral luminance BRS of the screen SC when the projection by the first projector100A stops is lower than the second threshold value TH2, and selecting the second processing PR2when the peripheral luminance BRS of the screen SC is no lower than the second threshold value TH2.

In other words, when the peripheral luminance BRS of the screen SC when the projection by the first projector100A stops is lower than the second threshold value TH2, the first processing PR1is selected, and when the peripheral luminance BRS of the screen SC is no lower than the second threshold value TH2, the second processing PR2is selected. Therefore, by appropriately setting the second threshold value TH2, it is possible to appropriately select either one of the first processing PR1and the second processing PR2.

The first program PGM1according to the present embodiment makes the first processor150A of the fourth projector100D execute performing the tiling projection in the first area AR1and the second area AR2of the screen SC by projecting the image light beams in the first area AR1by the first projector100A and the first projector group GA including one or more projectors, and projecting the image light beams in the second area AR2by the second projector group GB including two or more projectors, selecting one of the first processing PR1of adjusting the luminance of the light source111A of the first projector group GA in a plurality of times in the first period PE1and the second processing PR2of adjusting the luminance of the light source111A of the first projector group GA at a time in the second period PE2shorter than the first period PR1based on at least one of the luminance variation ΔBR of the input image and the peripheral luminance BRS of the screen SC when the projection by the first projector100A has stopped, deciding the first adjustment amount AD1of adjusting the output of the light source111A of the first projector group GA so that the luminance of the first area AR1in which the image light beam of the first projector group GA is projected coincides with the luminance of the second area AR2in which the image light beam of the second projector group GB is projected, performing the first adjustment processing PR11of applying the second adjustment amount AD2smaller than the first adjustment amount AD1to the first projector group GA when the first processing PR1is selected, projecting, by the first projector group GA, the image light beam after performing the first adjustment processing PR11, performing the second adjustment processing PR12of applying the third adjustment amount AD3no larger than the difference between the first adjustment amount AD1and the second adjustment amount AD2to the first projector group GA after the projecting the image light beam by the first projector group GA, and projecting, by the first projector group GA, the image light beam after performing the second adjustment processing PR12.

Therefore, it is possible for the first control program PGM1according to the present embodiment to exert substantially the same advantages as those of the method of controlling the projector100according to the present embodiment.

The fourth projector100D according to the present embodiment includes the light source111A, the first memory150B, and the first processor150A, wherein the first processor150A executes performing the tiling projection in the first area AR1and the second area AR2of the screen SC by projecting the image light beams in the first area AR1by the first projector100A and the first projector group GA including the second projector100B, and projecting the image light beams in the second area AR2by the second projector group GB including the third projector100C and the fourth projector100D, selecting one of the first processing PR1of adjusting the luminance of the light source111A of the first projector group GA in a plurality of times in the first period PE1and the second processing PR2of adjusting the luminance of the light source111A of the first projector group GA at a time in the second period PE2shorter than the first period PR1based on at least one of the luminance variation ΔBR of the input image and the peripheral luminance BRS of the screen SC when the projection by the first projector100A has stopped, deciding the first adjustment amount AD1of adjusting the output of the light source111A of the first projector group GA so that the luminance of the first area AR1in which the image light beam of the first projector group GA is projected coincides with the luminance of the second area AR2in which the image light beam of the second projector group GB is projected, performing the first adjustment processing PR11of applying the second adjustment amount AD2smaller than the first adjustment amount AD1to the first projector group GA when the first processing PR1is selected, projecting, by the first projector group GA, the image light beam after performing the first adjustment processing PR11, performing the second adjustment processing PR12of applying the third adjustment amount AD3no larger than the difference between the first adjustment amount AD1and the second adjustment amount AD2to the first projector group GA after the projecting the image light beam by the first projector group GA, and projecting, by the first projector group GA, the image light beam after performing the second adjustment processing PR12, and the fourth projector100D is included in the second projector group GB.

Therefore, it is possible for the fourth projector100D according to the present embodiment to exert substantially the same advantages as those of the method of controlling the projector100according to the present embodiment.

OTHER EMBODIMENTS

The present embodiment described above is a preferred aspect of implementation. It should be noted that the embodiment described above is not a limitation, but a variety of types of modified implementation are possible within the scope or the spirit thereof.

In the present embodiment, there is described when the first projector group GA is formed of a single projector, namely the second projector100B for the sake of convenience with reference toFIG.1throughFIG.8, but this is not a limitation. It is possible for the first projector group GA to include two or more projectors.

Further, in the present embodiment, there is described when the second projector group GB is constituted by the two projectors, namely the third projector100C and the fourth projector100D, but this is not a limitation. It is possible for the second projector group GB to include three or more projectors.

In the present embodiment, there is described when the fourth projector100D functions as the primary projector, but this is not a limitation. Any one of the first projector100A through the third projector100C can function as the primary projector.

Further, in the present embodiment, there is described when the first controller150of the fourth projector100D is provided with the projection instructor151, the stoppage detector152, the selector153, the decider154, the first processing unit155, the second processing unit156, and the image storage157, but this is not a limitation.

For example, it is possible for the first controller150of any one of the first projector100A through the third projector100C to be provided with the projection instructor151, the stoppage detector152, the selector153, the decider154, the first processing unit155, the second processing unit156, and the image storage157. Further, for example, it is possible for a second controller of the image supply device200to be provided with the projection instructor151, the stoppage detector152, the selector153, the decider154, the first processing unit155, the second processing unit156, and the image storage157.

Further, the functional units shown inFIG.3are for showing the functional configuration, and the specific implementation configuration is not particularly limited. In other words, it is not necessarily required to install the hardware individually corresponding to each of the constituents, but it is possible to adopt a configuration of realizing the functions of the plurality of constituents 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, or apart of the function realized by hardware can also be realized by software. Besides the above, the specific detailed configuration of the constituents of the projector100can arbitrarily be modified within the scope or the spirit thereof.

Further, the processing units of the flowcharts shown inFIG.6throughFIG.8are obtained by dividing the processing of the first controller150of the fourth projector100D in accordance with major processing contents in order to make the processing of the first controller150of the fourth projector100D easy to understand. The way of division or the names of the processing units shown in each of the flowcharts inFIG.6throughFIG.8are not a limitation, and it is also possible to divide the processing into a larger number of processing units, or it is also possible to divide the processing so that one processing unit includes a larger amount of processing in accordance with the processing contents. Further, the processing sequence of the flowcharts described above is not limited to the illustrated example.

Further, the method of controlling the projector100can be realized by making the first processor150A provided to the projector100execute the first control program PGM1corresponding to the method of controlling the projector100. Further, it is also possible to record the first control program PGM1on a recording medium storing the first control program PGM1in a computer-readable manner.

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, a CD-ROM (Compact Disc Read Only Memory), a DVD, a Blu-ray (registered trademark) disc, a magnetooptic disc, a flash memory, or a card-type recording medium. Further, the recording medium 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 projector100.

It is possible to realize the method of controlling the projector100by storing the first control program PGM1in a server device or the like, and then downloading the first control program PGM1from the server device to the projector100.

Supplementary Notes

Hereinafter, the conclusion of the present disclosure will supplementarily be noted.

Supplementary Note 1

A method of controlling a projector including performing tiling projection in a first area and a second area of a projection surface by projecting image light beams in the first area by a first projector and a first projector group including one or more projectors, and projecting image light beams in the second area by a second projector group including two or more projectors, selecting either one of first processing of adjusting luminance of a light source of the first projector group in two or more times in a first period based on at least one of a luminance variation of an input image and peripheral luminance of the projection surface and second processing of adjusting the luminance of the light source of the first projector group at a time in a second period shorter than the first period when projection by the first projector stops, deciding a first adjustment amount of adjusting output of the light source of the first projector group so that luminance of the first area in which the image light beams of the first projector group are projected coincides with luminance of the second area in which the image light beams of the second projector group are projected when the projection by the first projector stops, performing first adjustment processing of applying a second adjustment amount smaller than the first adjustment amount to the first projector group when the first processing is selected, projecting, by the first projector group, the image light beams after performing the first adjustment processing, performing second adjustment processing of applying a third adjustment amount which is no larger than a difference between the first adjustment amount and the second adjustment amount to the first projector group after the projecting the image light beams by the first projector group, and projecting, by the first projector group, the image light beams after performing the second adjustment processing.

In this way, compared to when executing the second processing of performing the adjustment at a time in the second period shorter than the first period, in the first processing, the luminance of the first projector group GA is adjusted in two or more times in the first period. Therefore, in the first processing, it is possible to prevent the user from having a feeling of strangeness during the execution of the processing of adjusting the luminance compared to when executing the second processing. Therefore, when the projection by the first projector stops, it is possible to prevent the user from having a feeling of strangeness during the execution of the processing of adjusting the luminance of the first projector group.

Supplementary Note 2

The method of controlling the projector described in Supplementary Note 1 further including deciding a fourth adjustment amount of adjusting output of a light source of the second projector group when the first processing is selected, wherein the first processing includes applying a fifth adjustment amount smaller than the fourth adjustment amount to the second projector group, projecting, by the second projector group, the image light beams after applying the fifth adjustment amount to the second projector group, applying a sixth adjustment amount which is no larger than a difference between the fourth adjustment amount and the fifth adjustment amount to the second projector group, and projecting, by the second projector group, the image light beams after applying the sixth adjustment amount to the second projector group.

In this way, compared to when executing the second processing of performing the adjustment at a time in the second period shorter than the first period, in the first processing, the luminance of the second projector group is adjusted in two or more times in the first period. Therefore, in the first processing, it is possible to prevent the user from having a feeling of strangeness during the execution of the processing of adjusting the luminance compared to when executing the second processing. Therefore, when the projection by the first projector stops, it is possible to prevent the user from having a feeling of strangeness during the execution of the processing of adjusting the luminance of the second projector group.

Supplementary Note 3

The method of controlling the projector described in Supplementary Note 2 wherein the first processing includes applying the second adjustment amount to the first projector group at a first time point in the first period, projecting, by the first projector group, the image light beams after applying the second adjustment amount to the first projector group, applying the fifth adjustment amount to the second projector group at the first time point, projecting, by the second projector group, the image light beams after applying the fifth adjustment amount to the second projector group, applying the third adjustment amount to the first projector group at a second time point subsequent to the first time point in the first period, projecting, by the first projector group, the image light beams after applying the third adjustment amount to the first projector group, applying the sixth adjustment amount to the second projector group at the second time point, and projecting, by the second projector group, the image light beams after applying the sixth adjustment amount to the second projector group.

In this way, it is possible to adjust the luminance of each of the first projector group and the second projector group at the same time at the first time point and the second time point in the first period. Therefore, it is possible to prevent the user from having a feeling of strangeness during the execution of the processing of adjusting the luminance of each of the first projector group and the second projector group.

Supplementary Note 4

The method of controlling the projector described in any one of Supplementary Note 1 through Supplementary Note 3 further including applying the first adjustment amount to the first projector group when the second processing is selected, and projecting, by the first projector group, the image light beams after applying the first adjustment amount to the first projector group.

In this way, when executing the second processing, it is possible to adjust the luminance of the first projector group in a shorter time and with a simpler processing compared to when executing the first processing.

Supplementary Note 5

The method of controlling the projector described in any one of Supplementary Note 1 through Supplementary Note 3 further including deciding a fourth adjustment amount of adjusting output of a light source of the second projector group when the second processing is selected, wherein the second processing includes applying the first adjustment amount to the first projector group in the second period, projecting, by the first projector group, the image light beams after applying the first adjustment amount to the first projector group, applying the fourth adjustment amount to the second projector group in the second period, and projecting, by the second projector group, the image light beams after applying the fourth adjustment amount to the second projector group.

In this way, when executing the second processing, it is possible to adjust the luminance of each of the first projector group and the second projector group in a shorter time and with a simpler processing compared to when executing the first processing.

Supplementary Note 6

The method of controlling the projector described in Supplementary Note 5 wherein the deciding the fourth adjustment amount includes deciding the fourth adjustment amount so that the luminance of the second area when the second projector group projects the image light beams after applying the fourth adjustment amount to the second projector group coincides with the luminance of the first area when the first projector group projects the image light beams after applying the first adjustment amount to the first projector group.

In this way, it is possible to decide the fourth adjustment amount to an appropriate value. In other words, it is possible to make the luminance of the second area coincide with the luminance of the first area.

Supplementary Note 7

The method of controlling the projector described in any one of Supplementary Note 1 through Supplementary Note 6 wherein the selecting either one of the first processing and the second processing includes selecting the first processing when a difference between an average pixel value of a first frame of an input image input to the first projector group and an average pixel value of a second frame prior to the first frame when the projection by the first projector stops is lower than a first threshold value, and selecting the second processing when the difference between the average pixel value of the first frame and the average pixel value of the second frame when the projection by the first projector stops is no lower than the first threshold value.

In this way, it is possible to appropriately select either one of the first processing and the second processing.

Supplementary Note 8

The method of controlling the projector described in any one of Supplementary Note 1 through Supplementary Note 6 wherein the selecting either one of the first processing and the second processing includes selecting the first processing when peripheral luminance of the projection surface when the projection by the first projector stops is lower than a second threshold value, and selecting the second processing when the peripheral luminance of the projection surface when the projection by the first projector stops is no lower than the second threshold value.

In this way, it is possible to appropriately select either one of the first processing and the second processing.

Supplementary Note 9

Anon-transitory computer-readable storage medium storing a program configured to make a processor of a projector execute performing tiling projection in a first area and a second area of a projection surface by projecting image light beams in the first area by a first projector and a first projector group including one or more projectors, and projecting image light beams in the second area by a second projector group including two or more projectors, selecting either one of first processing of adjusting luminance of a light source of the first projector group in two or more times in a first period based on at least one of a luminance variation of an input image and peripheral luminance of the projection surface and second processing of adjusting the luminance of the light source of the first projector group at a time in a second period shorter than the first period when projection by the first projector stops, deciding a first adjustment amount of adjusting output of the light source of the first projector group so that luminance of the first area in which the image light beams of the first projector group are projected coincides with luminance of the second area in which the image light beams of the second projector group are projected when the projection by the first projector stops, performing first adjustment processing of applying a second adjustment amount smaller than the first adjustment amount to the first projector group when the first processing is selected, projecting, by the first projector group, the image light beams after performing the first adjustment processing, performing second adjustment processing of applying a third adjustment amount which is no larger than a difference between the first adjustment amount and the second adjustment amount to the first projector group after the projecting the image light beams by the first projector group, and projecting, by the first projector group, the image light beams after performing the second adjustment processing.

In this way, the program described in Supplementary Note 9 exerts substantially the same advantages as those of the method of controlling the projector described in Supplementary Note 1.

Supplementary Note 10

A projector including a light source, a memory, and at least one processor, wherein the at least one processor is configured to execute performing tiling projection in a first area and a second area of a projection surface by projecting image light beams in the first area by a first projector and a first projector group including one or more projectors, and projecting image light beams in the second area by a second projector group including two or more projectors, selecting either one of first processing of adjusting luminance of a light source of the first projector group in two or more times in a first period based on at least one of a luminance variation of an input image and peripheral luminance of the projection surface and second processing of adjusting the luminance of the light source of the first projector group at a time in a second period shorter than the first period when projection by the first projector stops, deciding a first adjustment amount of adjusting output of the light source of the first projector group so that luminance of the first area in which the image light beams of the first projector group are projected coincides with luminance of the second area in which the image light beams of the second projector group are projected when the projection by the first projector stops, performing first adjustment processing of applying a second adjustment amount smaller than the first adjustment amount to the first projector group when the first processing is selected, projecting, by the first projector group, the image light beams after performing the first adjustment processing, performing second adjustment processing of applying a third adjustment amount which is no larger than a difference between the first adjustment amount and the second adjustment amount to the first projector group after the projecting the image light beams by the first projector group, and projecting, by the first projector group, the image light beams after performing the second adjustment processing, and the projector is included in either one of the first projector group and the second projector group.

In this way, the projector described in Supplementary Note 10 exerts substantially the same advantages as those of the method of controlling the projector described in Supplementary Note 1.