Title of Invention: INTERACTIVE SYSTEM, CONTROL
METHOD FOR INTERACTIVE SYSTEM, AND PROJECTOR
Technical Field
[0001] The present invention relates to an interactive system, a control method for the in
teractive system, and a projector.
Background Art
[0002] There has been proposed an interactive system that projects an image, which is based
on an image signal output from a computer, on a whiteboard or the like with a
projector, picks up an image of the projected image with an image pickup apparatus,
and recognizes operation of a user applied to the projected image with the computer.
[0003] For example, there is known a presentation system including a computer, a
projection-type video display apparatus (a projector) that projects a video on a
projection surface such as a screen, a selective transmission device that transmits light
in a specific wavelength band, an image pickup apparatus that picks up an image of the
screen or the like, and a pointing stick (a pointer) that is used for pointing a part of the
video, and emits infrared light from the distal end thereof (PTL 1). In such a pre
sentation system (an interactive system), it is possible to superimpose a rendered video
rendered by the pointing stick (the pointer) on a basic video.
[0004] There is also known an information input system (an interactive system) that
includes, in an electronic pen (an information input device), a reflecting unit having a
predetermined reflecting pattern, specifies the position of the reflecting unit on the
basis of a detection result obtained by detecting a wavelength component in reflected
light, and specifies an input position of information by the electronic pen on the basis
of the position of the reflecting unit.
Citation List
Patent Literature
[0005] PTL 1: JP-A-201 1-28629
PTL 2: JP-A-201 1-204059
Summary of Invention
Technical Problem
[0006] There is an interactive system that transmits an infrared signal for synchronization
from a projector to a light-emitting pen (an electronic pen) and synchronizes light
emission timing of the light-emitting pen and image pickup timing of an image pickup
unit included in the projector. However, when a plurality of the interactive systems are
used while being placed side by side, in some case, infrared signals for synchronization
emitted from projectors of the respective interactive systems interfere with one another
and synchronization with light-emitting pens of the respective interactive systems
cannot be correctly performed.
Solution to Problem
[0007] An advantage of some aspects of the invention is to solve at least a part of the
problems described above, and the invention can be implemented as the following
forms or application examples.
[0008] Application Example 1
This application example is directed to an interactive system including: a transmitter
configured to transmit an optical signal; and a projector. The projector includes: a
signal-intensity setting unit in which intensity information of a synchronization signal
is set; a signal-intensity control unit configured to control the intensity of the synchro
nization signal on the basis of the setting of the signal-intensity setting unit; a synchro
nization-signal transmitting unit configured to transmit the synchronization signal; and
an image pickup unit configured to pick up an image of the optical signal transmitted
from the transmitter. The transmitter includes: a receiving unit configured to receive
the synchronization signal; and an optical- signal transmitting unit configured to
transmit the optical signal in synchronization with the synchronization signal received
by the receiving unit.
[0009] With such an interactive system, intensity information of a synchronization signal to
be transmitted is set in the signal-intensity setting unit of the projector. The signalintensity
control unit controls the intensity of the synchronization signal on the basis of
the setting of the signal-intensity setting unit. The synchronization-signal transmitting
unit transmits the synchronization signal. The transmitter transmits an optical signal in
synchronization with the received synchronization signal. Consequently, by changing
the intensity of the synchronization signal, it is possible to reduce interference of the
synchronization signal with other interactive systems. The respective projectors can be
synchronized with transmitters of the projectors.
[0010] Application Example 2
This application example is directed to the interactive system according to the ap
plication example described above, wherein the projector further includes a synchro
nization-signal receiving unit configured to receive the synchronization signal. When
the synchronization- signal receiving unit receives a second synchronization signal
from another projector, the synchronization-signal transmitting unit transmits the syn
chronization signal in synchronization with the second synchronization signal.
[001 1] With such an interactive system, when the synchronization-signal receiving unit
receives a second synchronization signal from another projector, the synchronizationsignal
transmitting unit transmits the synchronization signal in synchronization with
the second synchronization signal. Consequently, since the transmitter is synchronized
with the second synchronization signal transmitted from the other projector, the r e
spective projectors can be synchronized with transmitters of the projectors.
[0012] Application Example 3
This application example is directed to the interactive system according to the ap
plication example described above, wherein the synchronization-signal transmitting
unit includes an infrared-light emitting diode. The synchronization signal transmitted
by the synchronization-signal transmitting unit is an infrared signal.
[0013] With such an interactive system, the synchronization signal is an infrared signal.
Consequently, the projector and the transmitter can be synchronized with each other.
[0014] Application Example 4
This application example is directed to the interactive system according to the ap
plication example described above, wherein the synchronization-signal transmitting
unit includes a plurality of the infrared-light emitting diodes. The signal-intensity
control unit changes the number of emitted lights of the plurality of infrared-light
emitting diodes to control the intensity of the synchronization signal.
[0015] With such an interactive system, the signal- intensity control unit can change the
intensity of the synchronization signal by changing the number of emitted lights of the
plurality of infrared-light emitting diodes.
[0016] Application Example 5
This application example is directed to the interactive system according to the ap
plication example described above, wherein the projector further includes: an operation
receiving unit configured to receive predetermined operation; and a control unit
configured to set, when the operation receiving unit receives the predetermined
operation, intensity information of the synchronization signal based on the prede
termined operation in the signal-intensity setting unit.
[0017] With such an interactive system, when the operation receiving unit receives prede
termined operation, the control unit sets intensity information of the synchronization
signal based on the predetermined operation in the signal-intensity setting unit. Con
sequently, a user can change the intensity of the synchronization signal.
[0018] Application Example 6
This application example is directed to a control method for an interactive system
including a transmitter configured to transmit an optical signal and a projector
including a signal-intensity setting unit in which intensity information of a synchro
nization signal is set. The method includes: a signal-intensity control step of the
projector controlling the intensity of the synchronization signal on the basis of the
setting of the signal-intensity setting unit; a synchronization-signal transmitting step of
the projector transmitting the synchronization signal; an image pickup step of the
projector picking up an image of the optical signal transmitted from the transmitter; a
receiving step of the transmitter receiving the synchronization signal; and an opticalsignal
transmitting step of the transmitter transmitting the optical signal in synchro
nization with the synchronization signal received by the receiving step.
[0019] With such a control method for the interactive system, by changing the intensity of
the synchronization signal, it is possible to reduce interference of the synchronization
signal with other interactive systems. Respective projectors can be synchronized with
transmitters of the projectors.
[0020] Application Example 7
This application example is directed to a projector including: a signal-intensity
setting unit in which intensity information of a synchronization signal is set; a signalintensity
control unit configured to control the intensity of the synchronization signal
on the basis of the setting of the signal-intensity setting unit; and a synchronizationsignal
transmitting unit configured to transmit the synchronization signal.
[0021] With such a projector, intensity information of a synchronization signal to be
transmitted is set in the signal-intensity setting unit. The signal-intensity control unit
controls the intensity of the synchronization signal on the basis of the setting of the
signal-intensity setting unit. The synchronization-signal transmitting unit transmits the
synchronization signal. Consequently, by changing the intensity of the synchronization
signal, it is possible to reduce interference of the synchronization signal with other in
teractive systems.
[0022] When the interactive system, the control method for the interactive system, and the
projector are constructed using a computer included in the projector, the forms and the
application examples can also be configured in a form of, for example, a program for
realizing the functions of the forms and the application examples or a recording
medium having the program recorded therein to be readable by the computer. As the
recording medium, it is possible to use various media readable by the computer such as
a flexible disk, an HDD (Hard Disk Drive), a CD-ROM (Compact Disk Read Only
Memory), a DVD (Digital Versatile Disk), a Blu-ray Disc (registered trademark), a
magneto-optical disk, a non-volatile memory card, internal storage devices
(semiconductor memories such as a RAM (Random Access Memory) and a ROM
(Read Only Memory)) of the projector, and an external storage device (a USB
(Universal Serial Bus) memory, etc.).
Brief Description of Drawings
[0023] [fig.l]Fig. 1 is a block diagram showing the configuration of an interactive system
according to an embodiment.
[fig.2]Fig. 2 is a block diagram showing the configuration of a light-emitting pen
according to the embodiment.
[fig.3]Fig. 3 is a timing chart representing synchronization timing in the interactive
system.
[fig.4]Fig. 4 is an explanatory diagram of interactive systems provided side by side.
[fig.5]Fig. 5 is an explanatory diagram of a menu image for setting light emission
intensity.
[fig.6]Fig. 6 is a flowchart of infrared light emission intensity switching processing of
a projector.
Description of Embodiment
[0024] Embodiment
As an embodiment, an interactive system that picks up an image of a projected image
and detects operation in the projected image on the basis of the pickup image is
explained.
[0025] Fig. 1 is a block diagram showing the configuration of an interactive system
according to this embodiment.
In Fig. 1, as an interactive system 1, a light-emitting pen 200 functioning as a
transmitter, a projector 100, a personal computer (PC) 300, and a projection surface S
such as a whiteboard are shown.
[0026] The projector 100 includes an image projecting unit 10, a control unit 20, an
operation receiving unit 21, a signal-intensity setting unit 22, an image-signal input
unit 31, an image processing unit 32, an image pickup and detecting unit 50, a lightemission
control unit 60 functioning as a signal-intensity control unit, an infrared-light
emitting unit 6 1 functioning as a synchronization-signal transmitting unit, and an
infrared-light receiving unit 62 functioning as a synchronization-signal receiving unit.
[0027] The image projecting unit 10 includes a light source 11, three liquid crystal light
valves 12R, 12G, and 12B functioning as light modulating devices, a projection lens 13
functioning as a projection optical system, and a light-valve driving unit 14. The image
projecting unit 10 modulates light emitted from the light source 11 in the liquid crystal
light valves 12R, 12G, and 12B to form image light and projects the image light from
the projection lens 13 to display the image light on the projection surface S or the like.
[0028] The light source 11 includes a light source lamp 1l a of a discharge type configured
by an extra-high pressure mercury lamp, a metal halide lamp, or the like and a reflector
1lb configured to reflect light radiated by the light source lamp 1l a to the liquid
crystal light valves 12R, 12G, and 12B side. The light emitted from the light source 11
is converted into lights having substantially uniform luminance distributions by a notshown
integrator optical system and, after being separated into color light components
of red R, green G, and blue B, which are the three primary colors of light, by a notshown
color separation optical system, respectively made incident on the liquid crystal
light valves 12R, 12G, and 12B.
[0029] The liquid crystal light valves 12R, 12G, and 12B are configured by, for example, a
liquid crystal panel in which liquid crystal is encapsulated between a pair of
transparent substrates. In the liquid crystal light valves 12R, 12G, and 12B, a plurality
of pixels (not shown in the figure) arrayed in a matrix shape are formed. A driving
voltage can be applied to the liquid crystal for each of the pixels. When the light-valve
driving unit 14 applies driving voltages corresponding to input image information to
the pixels, the pixels are set to light transmittance corresponding to the image in
formation. Therefore, the light emitting from the light source 11 is modulated by being
transmitted through the liquid crystal light valves 12R, 12G, and 12B. An image corre
sponding to the image information is formed for each of the color lights. Formed
images of the colors are combined for each of the pixels by a not-shown color com
bination optical system into a color image and then the color image is projected from
the projection lens 13.
[0030] The control unit 20 includes a CPU (Central Processing Unit), a RAM used for, for
example, temporary storage of various data, and a nonvolatile memory such as a mask
ROM, a flash memory, or an FeRAM (Ferroelectric RAM) (all of which are not shown
in the figure). The control unit 20 functions as a computer. The CPU operates
according to a control program stored in the nonvolatile memory, whereby the control
unit 20 collectively controls the operation of the projector 100. The control unit 20
includes a timer and measures, for example, timing for transmission of a synchro
nization signal and image pickup of an image pickup unit 51.
[0031] The operation receiving unit 2 1 receives input operation from a user. The operation
receiving unit 2 1 includes a plurality of operation keys for the user to give various in
structions to the projector 100. As the operation keys included in the operation
receiving unit 21, there are a power key for switching ON and OFF of a power supply,
a menu key for switching display and non-display of a menu image for performing
various kinds of setting, a cursor key used for, for example, movement of a cursor on
the menu image, a determination key for determining the various kinds of setting, and
the like. When the user operates (depresses) the operation keys of the operation
receiving unit 21, the operation receiving unit 2 1 receives the input operation and
outputs an operation signal corresponding to operation contents of the user to the
control unit 20.
[0032] As the operation receiving unit 21, a remote controller (not shown in the figure),
which can be remotely operated, may be used. In this case, the remote controller
transmits an operation signal of an infrared ray or the like corresponding to operation
contents of the user. A remote-controller-signal receiving unit receives the operation
signal and communicates the operation signal to the control unit 20. In this em
bodiment, the infrared-light receiving unit 62 also functions as the remotecontroller-
signal receiving unit.
[0033] The signal-intensity setting unit 22 is configured by a nonvolatile memory. Intensity
information of light emission intensity of an infrared signal (a synchronization signal)
transmitted from the infrared-light emitting unit 6 1 controlled by the light-emission
control unit 60 is set and stored in the signal-intensity setting unit 22. In this em
bodiment, in the signal-intensity setting unit 22, a "normal mode" for light emission at
normal light emission intensity or a "weak mode" for light emission at light emission
intensity lower than the normal light emission intensity can be set as a setting value of
the intensity information of the light emission intensity.
[0034] In the image-signal input unit 31, an input terminal (not shown in the figure) for
connection to the PC 300 via a cable CI is provided. An image signal is input to the
image-signal input unit 3 1 from the PC 300. The image-signal input unit 3 1 converts
the input image signal into image information of a form processable by the image
processing unit 32 and outputs the image information to the image processing unit 32.
[0035] The image processing unit 32 converts the image information input from the imagesignal
input unit 31 into image data representing gradations of the pixels of the liquid
crystal light valves 12R, 12G, and 12B and outputs the image data to the light-valve
driving unit 14. The converted image data is image data by color lights of R, G, and B.
The converted image data is configured by a plurality of pixel values corresponding to
all the pixels of the liquid crystal light valves 12R, 12G, and 12B. The pixel values
specify light transmittances of the pixels corresponding thereto. Intensities (gradations)
of lights emitted from the pixels are specified by the pixel values. The image
processing unit 32 applies, on the basis of an instruction of the control unit 20, for
example, image quality adjustment processing for adjusting brightness, contrast,
sharpness, hue, and the like to the converted image data. Further, the image processing
unit 32 generates image data of a menu image or the like on the basis of an instruction
of the control unit 20.
[0036] The image processing unit 32 includes a rendering memory 32a. The rendering
memory 32a stores rendering data based on rendering operation by the light-emitting
pen 200.
[0037] The image processing unit 32 receives position information of the light-emitting pen
200 from the image pickup and detecting unit 50. The position information is in
formation representing a position pointed by the light-emitting pen 200 in an image (a
display image) displayed by the image projecting unit 10. The image processing unit
32 stores rendering data in the rendering memory 32a on the basis of a position where
rendering operation of the light-emitting pen 200 is performed. The image processing
unit 32 combines the rendering data of the rendering memory 32a with the image data
input from the image-signal input unit 31 and outputs combined image data to the
light-valve driving unit 14.
[0038] When the light-valve driving unit 14 drives the liquid crystal light valves 12R, 12G,
and 12B according to the image data input from the image processing unit 32, the
liquid crystal light valves 12R, 12G, and 12B form an image corresponding to the
image data. The image is projected from the projection lens 13.
[0039] The image pickup and detecting unit 50 includes an image pickup unit 51, an image
analyzing unit 52, and a position-information detecting unit 53. The image pickup and
detecting unit 50 is controlled by the control unit 20. The image pickup and detecting
unit 50 picks up an image of the projection surface S, analyzes the image, and detects
the position of the light-emitting pen 200.
[0040] The image pickup unit 51 includes an image pickup device or the like (not shown in
the figure) configured by a CCD (Charge Coupled Device) sensor, a CMOS
(Complementary Metal Oxide Semiconductor) sensor, or the like and an image pickup
lens (not shown in the figure) for focusing light emitted from an image pickup target
on the image pickup device. The image pickup unit 51 is arranged in the vicinity of the
projection lens 13 of the projector 100. The image pickup unit 5 1 picks up an image of
a range including an image projected on the projection surface S (hereinafter referred
to as "projected image" as well) on the basis of an instruction of the control unit 20.
The image pickup unit 51 sequentially generates image information representing the
picked-up image (hereinafter referred to as "pickup image" as well) and outputs the
image information to the image analyzing unit 52.
[0041] The image analyzing unit 52 includes a processing device, a memory, and the like for
image analysis (all of which are not shown in the figure). The image analyzing unit 52
performs an analysis of the image information of the pickup image input from the
image pickup unit 51. The image analyzing unit 52 outputs an analysis result to the
position-information detecting unit 53. The image analyzing unit 52 converts position
information on the pickup image into position information on an image based on the
image signal.
[0042] The position-information detecting unit 53 detects position information of the lightemitting
pen 200 on the basis of the analysis result of the image analyzing unit 52. The
position-information detecting unit 53 outputs the position information of the lightemitting
pen 200 to the image processing unit 32.
[0043] Software (a device driver) for using the light-emitting pen 200 as a rendering device
(a transmitter) is stored in the nonvolatile memory of the control unit 20. In a state in
which the software is started, the image processing unit 32 recognizes, on the basis of
the position information input from the image pickup and detecting unit 50, each of
positions where rendering operation of the light-emitting pen 200 is performed in a
projected image. The image processing unit 32 causes the rendering memory 32a to
store rendering data and outputs image data based on the rendering data to the lightvalve
driving unit 14.
[0044] The light-emission control unit 60 controls light emission of the infrared-light
emitting unit 6 1 on the basis of an instruction of the control unit 20. Specifically, the
light-emission control unit 60 can light an infrared-light emitting diode included in the
infrared-light emitting unit 6 1 by supplying electric power to the infrared-light
emitting diode and extinguish the infrared-light emitting diode by stopping the supply
of the electric power.
[0045] The light-emission control unit 60 can control light emission intensity of an infrared
signal emitted by the infrared-light emitting unit 61. In this embodiment, the infraredlight
emitting unit 6 1 includes a plurality of the infrared-light emitting diodes. The
light-emission control unit 60 switches the number of the infrared-light emitting
diodes, which are caused to emit lights, to control the light emission intensity.
Specifically, the light-emission control unit 60 can switch the infrared-light emitting
diodes to a normal mode for lighting and extinguishing all the infrared-light emitting
diodes and a weak mode for lighting and extinguishing a part of the infrared-light
emitting diodes.
[0046] The infrared-light emitting unit 6 1 is configured by an infrared-light emitting device
(not shown in the figure) or the like including an infrared-light emitting diode. The
infrared-light emitting unit 6 1 causes the infrared-light emitting diode to emit light on
the basis of control information input from the light-emission control unit 60 and
transmits an infrared signal to the outside. Specifically, the infrared-light emitting unit
6 1 transmits a synchronization signal of infrared light.
[0047] The infrared-light receiving unit 62 includes an infrared receiving module. The
infrared-light receiving unit 62 receives an infrared signal emitted from another
projector or the like and notifies the control unit 20 of the infrared signal. In this em
bodiment, the infrared-light receiving unit 62 is used as a remote-controller-signal
receiving unit as well.
[0048] Next, the light-emitting pen 200 is explained. The light-emitting pen 200 includes, at
a distal end portion (a pen tip) of a pen-like main body, a press switch, a pen reception
unit functioning as a receiving unit configured to receive a synchronization signal, and
a light-emitting diode configured to emit infrared light as an optical signal.
Fig. 2 is a block diagram showing the configuration of the light-emitting pen 200
according to this embodiment.
[0049] The light-emitting pen 200 includes a pen control unit 220, a press switch 221, a pen
reception unit 230 configured to receive an infrared signal, which is a synchronization
signal, and a light-emitting diode 240 configured to emit infrared light. When the user
performs operation (pressing operation) for pressing the pen tip of the light-emitting
pen 200 against the projection surface S and presses the press switch 221, the pen
control unit 220 causes the light-emitting diode 240 to emit light to be synchronized
with the synchronization signal received by the pen reception unit 230. The pen control
unit 220 and the light-emitting diode 240 are equivalent to the optical-signal
transmitting unit.
[0050] Timing of the synchronization signal emitted from the infrared- light emitting unit 6 1
of the projector 100, timing when the light-emitting pen 200 emits light, and timing
when the projector 100 picks up an image of emitted light of the light-emitting pen 200
are explained.
Fig. 3 is a timing chart representing synchronization timing in the interactive system
1.
[0051] As shown in Fig. 3, the synchronization signal transmitted by the infrared- light
emitting unit 6 1 of the projector 100 is output at a time interval tl. The control unit 20
including the timer instructs the light-emission control unit 60 to cause the infraredlight
emitting unit 6 1 to transmit the synchronization signal. In the light-emitting pen
200, the reception unit receives the synchronization signal. After time t2 from the
reception of the synchronization signal, the light-emitting pen 200 causes the lightemitting
diode to emit light. The image pickup unit 5 1 of the projector 100 picks up the
light emission of the light-emitting pen 200 after time t3 from the transmission of the
synchronization signal by the infrared-light emitting unit 6 1 according to an instruction
from the control unit 20. The time t3 is larger than the time t2.
[0052] At such timings, the infrared-light emitting unit 6 1 of the projector 100 transmits the
synchronization signal, the light-emitting pen 200 emits light, and the image pickup
unit 5 1 of the projector 100 picks up an image. Therefore, the projector 100 can
correctly pick up an image of the emitted light of the light-emitting pen 200.
[0053] A form in which a plurality of the interactive systems are set is explained.
Fig. 4 is an explanatory diagram of the interactive systems provided side by side.
[0054] As shown in Fig. 4, the interactive system 1 includes the light-emitting pen 200 and
the projector 100. The interactive system 1 is set to be opposed to the projection
surface S. The projector 100 includes the infrared- light emitting unit 6 1 and the
infrared- light receiving unit 62. An interactive system 2 includes a light-emitting pen
600 and a projector 500. The interactive system 2 is set to be opposed to a projection
surface SI. The projector 500 includes an infrared-light emitting unit 561 and an
infrared-light receiving unit 562. The interactive system 1 and the interactive system 2
are provided side by side.
[0055] When the interactive systems are provided side by side in this way, in some case, an
infrared signal emitted from the projector of one interactive system is received by the
light-emitting pen of the other interactive system. Fig. 4 shows a form in which an
infrared signal IR emitted by the infrared- light emitting unit 561 of the projector 500 is
received by the light-emitting pen 200 of the interactive system 1. Since the lightemitting
pen 200 is used near the projection surface S, the light-emitting pen 200 often
receives the infrared signal IR reflected by the projection surface S.
[0056] When the light-emitting pen 200 receives an infrared signal (a second synchro
nization signal) emitted from the projector 500, light emission timing of the lightemitting
pen 200 shifts. The image pickup unit 5 1 of the projector 100 cannot normally
pickup an image of emitted light of the light-emitting pen 200. Therefore, an in
teractive function does not normally operate. In this embodiment, the operation of the
interactive function is stabilized by changing the light emission intensity of an infrared
signal transmitted from the infrared- light emitting unit 6 1 or tuning light emission
timing of the infrared signal with the synchronization signal (the second synchro
nization signal) emitted from the other projector 500. Details are explained below.
[0057] Setting of light emission intensity of the infrared- light emitting unit 6 1 is explained.
In the projector 100 in this embodiment, the user can perform setting of the light
emission intensity of an infrared signal (a synchronization signal) according to a menu
image. When determining that another projector is present around the projector 100,
the projector 100 switches the light emission intensity on the basis of a setting value of
the light emission intensity.
Fig. 5 is an explanatory diagram of the menu image for setting the light emission
intensity.
[0058] When the menu key included in the operation receiving unit 2 1 is depressed and a
light emission intensity setting menu is selected, the control unit 20 instructs the image
processing unit 32 to display a light emission intensity setting menu image Ml shown
in Fig. 5.
[0059] A character string "light emission intensity setting" is displayed in an upper part of
the light emission intensity setting menu image Ml. Under the character string, a
character string "When another projector is present around the projector, weaken a
signal transmitted to the light-emitting pen?" is displayed. "Weaken" and "Not
weaken" are displayed as setting candidates in the center of the light emission intensity
setting menu image Ml. "Weaken" means that the light emission intensity is set in the
weak mode. "Not weaken" indicates that the light emission intensity is set in the
normal mode. The user selects and determines desired setting out of the setting
candidates displayed on the light emission intensity setting menu image Ml, whereby
the control unit 20 stores information concerning a setting value of the setting (the
mode) in the signal-intensity setting unit 22. Operation at this point is equivalent to the
predetermined operation.
[0060] Next, switching processing for the light emission intensity of an infrared signal
(hereinafter referred to as "infrared light emission intensity switching processing")
executed during the start of the projector 100 is explained. Note that the infrared light
emission intensity switching processing is executed at periodic timing after the start as
well.
Fig. 6 is a flowchart of the infrared light emission intensity switching processing for
the projector 100.
[0061] When the projector 100 is started, the control unit 20 determines whether another
projector is present around the projector 100 (step S101). Specifically, the control unit
20 instructs the light-emission control unit 60 to stop transmission of an infrared signal
including a synchronization signal. The control unit 20 determines whether the
infrared- light receiving unit 62 is receiving an infrared signal. If the infrared- light
receiving unit 62 is receiving an infrared signal, the control unit 20 determines that the
infrared signal is an infrared signal transmitted from another projector and determines
that another projector is present around the projector 100.
[0062] When another projector is present around the projector 100 (step S101: YES), the
control unit 20 synchronizes the projector 100 with the other projector (step S102).
Specifically, the control unit 20 instructs the light-emission control unit 60 to be syn
chronized with a synchronization signal (a second synchronization signal) of the
infrared light received by the infrared- light receiving unit 62 and causes the infraredlight
emitting unit 6 1 to transmit the synchronization signal of the infrared light. That
is, the control unit 20 tunes light emission timing of the infrared light with the synchro
nization signal (the second synchronization signal) of the other projector.
[0063] The control unit 20 determines whether the setting of the light emission intensity is in
the "weak mode" (step S103). Specifically, the control unit 20 determines whether the
setting of the light emission intensity is in the "weak mode" referring to the setting
value of the light emission intensity stored in the signal-intensity setting unit 22.
[0064] When the setting of the light emission intensity is in the "weak mode" (step S103:
YES), the control unit 20 instructs the light-emission control unit 60 to reduce the light
emission intensity of the infrared light (the synchronization signal) emitted by the
infrared- light emitting unit 6 1 (step S104). The control unit 20 ends the infrared light
emission intensity switching processing.
[0065] When the setting of the light emission intensity is not in the "weak mode" (step S103:
NO), that is, the setting of the light emission intensity is in the "normal mode", the
control unit 20 instructs the light-emission control unit 60 to set the light emission
intensity of the infrared light (the synchronization signal) emitted by the infrared- light
emitting unit 6 1 to normal (step S105). The control unit 20 ends the infrared light
emission intensity switching processing.
[0066] When another projector is absent around the projector 100 (step S101: NO), the
control unit 20 shifts to step S105 and sets the light emission intensity of the infrared
light to normal. The control unit 20 ends the infrared light emission intensity switching
processing.
[0067] According to the embodiment explained above, effects explained below are obtained.
(1) The light-emission control unit 60 of the projector 100 of the interactive system 1
controls light emission intensity of an infrared signal, which is a synchronization
signal, transmitted by the infrared-light emitting unit 61. Consequently, when the
intensity of the synchronization signal is reduced, it is possible to reduce interference
of the synchronization signal with the other interactive system 2. In the respective in
teractive systems, the projectors can be synchronized with the light-emitting pens of
the projectors. This is useful because influence due to an environment of use is reduced
and the respective projectors can stably perform the interactive function using the
light-emitting pens of the projectors.
[0068] (2) The projector 100 of the interactive system 1 can display the light emission
intensity setting menu image Ml for setting the light emission intensity of an infrared
signal, which is a synchronization signal. The user can select and set the light emission
intensity of the infrared signal. When the other projector 500 is present around the
projector 100, the infrared-light emitting unit 6 1 of the projector 100 emits an infrared
signal according to the setting of the light emission intensity. Consequently, con
venience is improved because the user can set the light emission intensity of the
infrared signal.
[0069] (3) When the other projector 500 is present around the projector 100 of the in
teractive system 1, that is, when the infrared-light receiving unit 62 receives a synchro
nization signal (a second synchronization signal) transmitted from the other projector
500, the projector 100 transmits a synchronization signal synchronized with the
received synchronization signal (second synchronization signal) from the infrared-light
transmitting unit 61. That is, the projector 100 and the projector 500 synchronize (tune)
timings of the synchronization signals to be transmitted. Consequently, the lightemitting
pen 200 and the light-emitting pen 600 can be synchronized with the projector
100 and the projector 500. Therefore, the respective projectors can pick up images of
emitted lights of the light-emitting pens of the projectors. This is useful because the re
spective projectors can stably perform the interactive function by the light-emitting
pens.
[0070] (4) The projector 100 of the interactive system 1 executes the infrared light emission
intensity switching processing at periodic timings at the start and after the start of the
projector 100. Consequently, it is possible to determine at the start and periodically
whether the other projector 500 is present. This is useful because it is possible to im
mediately change the light emission intensity of infrared light (an infrared signal) when
the presence of another projector is detected.
[0071] (5) The synchronization signal emitted by the projector 100 of the interactive system
1 is an infrared signal. Consequently, it is possible to simplify the configurations of the
projector 100 and the light-emitting pen 200.
[0072] (6) The light-emission control unit 60 of the projector 100 of the interactive system 1
changes the number of emitted lights of the plurality of infrared-light emitting diodes
included in the infrared-light emitting unit 6 1 to change the light emission intensity of
the infrared signal. Consequently, it is possible to switch the light emission intensity of
the infrared signal to the normal mode and the weak mode.
[0073] Note that the invention is not limited to the embodiment explained above and can be
carried out while being applied with various modifications, alterations, and the like.
[0074] Modification 1
In the embodiment, when the other projector 500 is present around the projector 100,
the infrared-light emitting unit 6 1 of the projector 100 emits the infrared signal
according to the setting value of the light emission intensity set by the user. However,
the infrared-light emitting unit 6 1 may emit the infrared signal according to the setting
value of the light emission intensity set by the user irrespective of the presence of the
projector 500 around the projector 100.
[0075] Modification 2
In the embodiment, when the other projector 500 is present around the projector 100,
the infrared-light emitting unit 6 1 of the projector 100 emits the infrared signal
according to the light emission intensity set by the user. However, the light emission
intensity is not limited to the light emission intensity set by the user. For example, the
light emission intensity may be switched according to the light reception intensity of
an infrared signal of the other projector 500 received by the infrared-light receiving
unit 62. Specifically, when the light reception intensity is equal to or higher than prede
termined intensity, the light-emission control unit 60 may determine that the other
projector 500 is present near the projector 100 and reduce the light emission intensity
of the light emission of the infrared-light emitting unit 6 1 (the weak mode). When the
light reception intensity is lower than the predetermined intensity, the light-emission
control unit 60 may determine that the other projector 500 is preset far from the
projector 100 and increase the light emission intensity (the normal mode).
[0076] Modification 3
In the embodiment, in the infrared light emission intensity switching processing,
after the projector 100 is synchronized with the other projector 500, the control unit 20
reads out the setting value of the light emission intensity from the signal-intensity
setting unit 22 and causes the light-emission control unit 60 to switch the light
emission intensity of the infrared signal according to the setting value. However, the
infrared light emission intensity switching processing is not limited to this. When
being synchronized with the projector 500, the projector 100 may display a menu
image same as the light emission intensity setting menu image Ml on a projected
image. The projector 100 may cause the user to select and set light emission intensity
on the menu image. The control unit 20 may cause the light-emission control unit 60 to
switch the light emission intensity of the infrared signal according to the set light
emission intensity.
[0077] Modification 4
In the embodiment, the light emission intensity of the infrared signal controlled by
the light-emission control unit 60 and emitted by the infrared- light emitting unit 6 1 can
be switched to the "normal mode" and the "weak mode". However, the switching of
the light emission intensity is not limited to the two stages. For example, the light
emission intensity may be switchable in three or more stages.
[0078] Modification 5
In the embodiment, the setting of the light emission intensity of the infrared signal is
performed by displaying the light emission intensity setting menu image Ml.
However, the setting of the light emission intensity of the infrared signal is not limited
to this. For example, a key for switching the light emission intensity may be provided
in the operation receiving unit 21. The user may depress the key to change the setting
value of the light emission intensity and cause the signal-intensity setting unit 22 to set
and store the setting value.
[0079] Modification 6
In the embodiment, the synchronization signal is the infrared signal (the infrared
light). However, the synchronization signal is not limited to this. For example, the syn
chronization signal may be visible light or may be a radio wave for radio commu
nication or the like.
[0080] Modification 7
In the embodiment, the transmitter is the light-emitting pen 200 that emits the
infrared light. However, the transmitter is not limited to such a light-emitting pen. For
example, the transmitter may be a transmitter that emits visible light or may use a radio
wave for radio communication or the like.
[0081] Modification
In the embodiment, an apparatus that supplies the image signal to the projector 100 is
the PC 300. However, the apparatus is not limited to a personal computer and may be
other image supply apparatuses.
[0082] Modification 9
In the embodiment, the projector 100 and the PC 300 are connected by the cable CI.
However, input and output of information may be performed by radio communication.
[0083] Modification 10
In the embodiment, the light source 11 includes the light source lamp 1l a of the
discharge type. However, solid-state light sources such as an LED (Light Emitting
Diode) light source and a laser and other light sources can also be used.
[0084] Modification 1 1
In the embodiment, in the projector 100, the liquid crystal light valves 12R, 12G, and
12B of a transmission type are used as the light modulating devices. However, light
modulating devices of a reflection type such as liquid crystal light valves of the r e
flection type can also be used. Further, for example, a micro-mirror array device that
controls an emitting direction of incident light for each of micro-mirrors functioning as
pixels to thereby modulate light emitted from a light source can also be used.
Reference Signs List
[0085] 1, 2 Interactive systems
10 Image projecting unit
11 Light source
11a Light source lamp
1lb Reflector
12R, 12G, 12B Liquid crystal light valves
13 Projection lens
14 Light-valve driving unit
20 Control unit
2 1 Operation receiving unit
22 Signal-intensity setting unit
3 1 Image- signal input unit
32 Image processing unit
32a Rendering memory
50 Image pickup and detecting unit
51 Image pickup unit
52 Image analyzing unit
53 Position-information detecting unit
60 Light-emission control unit
6 1 Infrared- light emitting unit
62 Infrared-light receiving unit
100, 500 Projectors
200, 600 Light-emitting pens
220 Pen control unit
221 Press switch
230 Pen reception unit
240 Light-emitting diode
300 PC
561 Infrared-light emitting unit
562 Infrared-light receiving unit
S, SI Projection surfaces

Claims
[Claim 1] An interactive system comprising:
a transmitter configured to transmit an optical signal; and
a projector,
the projector including:
a signal-intensity setting unit in which intensity information of a syn
chronization signal is set;
a signal-intensity control unit configured to control intensity of the syn
chronization signal on the basis of the setting of the signal-intensity
setting unit;
a synchronization-signal transmitting unit configured to transmit the
synchronization signal; and
an image pickup unit configured to pick up an image of the optical
signal transmitted from the transmitter, and
the transmitter including:
a receiving unit configured to receive the synchronization signal; and
an optical- signal transmitting unit configured to transmit the optical
signal in synchronization with the synchronization signal received by
the receiving unit.
[Claim 2] The interactive system according to claim 1, wherein
the projector further includes a synchronization-signal receiving unit
configured to receive the synchronization signal, and
when the synchronization-signal receiving unit receives a second syn
chronization signal from another projector, the synchronization-signal
transmitting unit transmits the synchronization signal in synchro
nization with the second synchronization signal.
[Claim 3] The interactive system according to claim 1 or 2, wherein
the synchronization- signal transmitting unit includes an infrared-light
emitting diode, and
the synchronization signal transmitted by the synchronization-signal
transmitting unit is an infrared signal.
[Claim 4] The interactive system according to claim 3, wherein
the synchronization- signal transmitting unit includes a plurality of the
infrared-light emitting diodes, and
the signal-intensity control unit changes the number of emitted lights of
the plurality of infrared-light emitting diodes to control the intensity of
the synchronization signal.
WO 2014/045560 PCT/JP2013/005456
[Claim 5] The interactive system according to any one of claims 1 to 4, wherein
the projector further includes:
an operation receiving unit configured to receive predetermined
operation; and
a control unit configured to set, when the operation receiving unit
receives the predetermined operation, intensity information of the syn
chronization signal based on the predetermined operation in the signalintensity
setting unit.
[Claim 6] A control method for an interactive system including a transmitter
configured to transmit an optical signal and a projector including a
signal-intensity setting unit in which intensity information of a synchro
nization signal is set,
the method comprising:
a signal-intensity control step of the projector controlling intensity of
the synchronization signal on the basis of the setting of the signalintensity
setting unit;
a synchronization-signal transmitting step of the projector transmitting
the synchronization signal;
an image pickup step of the projector picking up an image of the optical
signal transmitted from the transmitter;
a receiving step of the transmitter receiving the synchronization signal;
and
an optical- signal transmitting step of the transmitter transmitting the
optical signal in synchronization with the synchronization signal
received by the receiving step.
[Claim 7] A projector comprising:
a signal-intensity setting unit in which intensity information of a syn
chronization signal is set;
a signal-intensity control unit configured to control the intensity of the
synchronization signal on the basis of the setting of the signal-intensity
setting unit; and
a synchronization-signal transmitting unit configured to transmit the
synchronization signal.