JP2017138871A - Position detection system, position detection device, and position detection method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a position detection device that prevents a reduction in detection accuracy when detection of a pointing element is performed in a wide range by arranging a plurality of projection systems including interactive projectors and light curtain units.SOLUTION: A position detection system 1000 includes a first position detection system 900a and a second position detection system 900b. The first position detection system 900a includes: a first layered detection light radiation part 440a that periodically radiates first detection light for detecting a first pointed position pointed on a first operation surface 920a; and a first control part for controlling radiation timing of the first detection light unit. The second position detection device 900b includes: a second layered detection light radiation part 440b that periodically radiates second detection light for detecting a second pointed position pointed on a second operation surface 920b; and a second control part for controlling the second detection light to be radiated at timing different from the radiation timing of the first detection light.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a position detection device capable of detecting an indication position of an indicator on an operation surface.

  Patent Document 1 discloses an interactive projector having a function as a position detection device. These interactive projectors project a projection screen onto a screen, capture an image including an indicator (pointing element) such as a light-emitting pen and a finger, and detect the position of the indicator using the captured image. Is possible. That is, the interactive projector recognizes that a predetermined instruction such as drawing is input to the projection screen when the tip of the indicator is in contact with the screen, and redraws the projection screen according to the instruction. . Therefore, the user can input various instructions using the projection screen as a user interface.

  In Patent Document 1, a light irradiation device (also referred to as a “light curtain unit”) that emits detection light in the form of curtains (or layers) on the surface of a screen is used for detection of an indicator. If the detection light is reflected by the indicator when it touches the screen, the position of the reflected light is captured by the camera, so the position of the indicator on the projection screen can be determined by analyzing the captured image. Can be determined.

Japanese Patent Laying-Open No. 2015-158887

  As described above, there are cases where a plurality of projection systems including an interactive projector and a light curtain unit are arranged to detect an indicator in a wide range. Then, a part of the irradiation range of the detection light from the adjacent light curtain unit may overlap, and in the range where the two detection lights overlap, the two detection lights are irradiated to the indicator from different directions. . In the interactive projector, since the indication position by the indicator on the projection screen is detected by imaging the reflected light of the detection light by the indicator, when two reflected lights are imaged for one indicator, There is a possibility that the detection accuracy is lowered.

  The problems as described above are not limited to interactive projectors that detect the indication position of a non-luminous indicator using a camera and a light curtain unit. This is a problem common to the position detection device to detect.

  SUMMARY 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.

(1) According to one aspect of the present invention, a first position detection device that detects a position on a first operation surface, and a position on a second operation surface adjacent to the first operation surface are detected. And a second position detection device that provides a position detection system. In the position detection system, the first position detection device periodically emits first detection light for detecting a first indicated position indicated by a non-light emitting indicator on the first operation surface. A first irradiating unit that irradiates; a first imaging unit that receives light in a wavelength region including a wavelength of the first detection light, images the first operation surface, and generates a first captured image; A first detection unit that detects the first designated position based on the first captured image; and a first control that controls an irradiation timing of the first detection light by the first irradiation unit; The second position detecting device emits second detection light for detecting a second indicated position indicated by using the non-light emitting indicator on the second operation surface. A second irradiating unit for periodically irradiating; receiving light in a wavelength region including a wavelength of the second detection light; A second imaging unit that images the operation surface of the second imaging unit to generate a second captured image; a second detection unit that detects the second designated position based on the second captured image; A second control unit that controls the second irradiation unit so that the second detection light is irradiated at a timing different from the irradiation timing of the first detection light.
According to this position detection system, since the first detection light from the first position detection device and the second detection light from the second position detection device are irradiated at different timings, they are the same. Compared with the case where irradiation is performed at the timing, a period in which the first detection light and the second detection light overlap is shortened. Therefore, the period during which a plurality of reflected lights from the non-light emitting indicator exist is shortened, and a decrease in detection accuracy is suppressed.

(2) In the position detection system, the second control unit of the second position detection device includes a first irradiation period in which the first detection light of the first position detection device is irradiated, The second detection light is emitted so that the second detection light is emitted at a timing such that a part of the second position detection apparatus overlaps with the second irradiation period during which the second detection light is emitted. The overlapping irradiation period in which the first irradiation period and the second irradiation period overlap may be 50% or less of the first irradiation period.
If it does in this way, since the period when the 1st detection light and the 2nd detection light overlap will be 50% or less, a fall of detection accuracy is further controlled.

(3) The position detection system further comprising: a light emitting unit that periodically emits light; and a light emission control unit that controls a light emission timing of the light emitting unit, and the first or second operation surface. A self-luminous indicator used to indicate an upper position; and in the position detection system, a first imaging period for imaging by the first imaging unit and a second imaging for imaging by the second imaging unit At least part of the imaging period overlaps, and the light emission control unit of the self-emission indicator emits light during the overlapping imaging period in which the first imaging period and the second imaging period overlap. You may control to do.
According to this configuration, it is possible to detect the position indicated by the self-luminous indicator. Since the self-emission indicator emits light during the overlapping imaging period in which the first imaging period and the second imaging period overlap, one light emission is either the first position detection device or the second position detection device. Since an image is always taken in, detection omission can be suppressed.

(4) In the position detection system, the first position detection device further includes a first projection unit that projects an image on the first operation surface, and the second position detection device includes You may further provide the 2nd projection part which projects an image on the 2nd operation surface.
According to this configuration, an appropriate image corresponding to the indication position of the indicator can be projected on the operation surface.

  The present invention can be realized in various forms, for example, a position detection device, a position detection method, a computer program for realizing the function of the method or device, and not a temporary recording of the computer program. It can be realized in various forms such as a recording medium (non-transitory storage medium).

It is a front view of the wide area position detection system as one embodiment of the present invention. It is a perspective view of the position detection system of a 1st embodiment. It is a front view of a position detection system. It is a side view of a position detection system. It is a block diagram which shows the internal structure of a projector and a self-light-emitting indicator. It is explanatory drawing which shows a mode that two projectors operate | move synchronously. It is a timing chart which shows the light emission timing of layered detection light. It is explanatory drawing of the irradiation range of layered detection light. It is explanatory drawing of the irradiation range of layered detection light. It is a timing chart which shows the other example of the light emission timing of layered detection light. It is a front view which shows the wide area position detection system as 2nd Embodiment. It is a perspective view of the position detection system of 2nd Embodiment. It is a side view of a position detection system. It is a block diagram which shows the internal structure of the projector of 2nd Embodiment.

A. First embodiment:
FIG. 1 is a front view showing a schematic configuration of a wide area position detection system 1000 as an embodiment of the present invention. The wide area position detection system 1000 includes a first position detection system 900a and a second position detection system 900b. In the wide area position detection system 1000, two projection screen surfaces SSa and SSb are arranged adjacent to each other, and the self-luminous indicator 70 and the non-luminous indicator 80 (non-luminous indicator) are arranged in a wide range including the projection screen surfaces SSa and SSb. This is a system for detecting the indicated position by a pen or a finger. The wide area position detection system 1000 in this embodiment is also referred to as a “position detection system”.

  The first position detection system 900a and the second position detection system 900b have the same configuration and can be used alone. Hereinafter, when the first position detection system 900a and the second position detection system 900b are distinguished from each other, “a” and “b” are appended to the reference numerals of the respective constituent elements. On the other hand, when the first position detection system 900a and the second position detection system 900b are not distinguished from each other, both are simply referred to as “position detection system 900”, and the reference numerals of components and the like are also “a” and “a” at the end. b ”is omitted.

  FIG. 2 is a perspective view of the position detection system 900. The position detection system 900 includes an interactive projector 100 (hereinafter also simply referred to as “projector 100”) as a position detection device, a screen plate 920 that provides an operation surface, and a self-luminous indicator 70. The projector 100 includes a layered detection light irradiation unit 440 (light curtain unit). In FIG. 2, for convenience of illustration, the layered detection light irradiation unit 440 is drawn separately from the projector 100. The front surface of the screen plate 920 is used as a projection screen surface (SS). The projector 100 is fixed to the front and above the screen plate 920 by a support member 910. In FIG. 2, the projection screen surface SS is arranged vertically, but the system 900 can also be used with the projection screen surface SS arranged horizontally.

  The projector 100 projects a projection screen PS (Projected Screen) on the projection screen surface SS. The projection screen PS usually includes an image drawn in the projector 100. When there is no image drawn in the projector 100, light is emitted from the projector 100 to the projection screen PS, and a white image is displayed. In this specification, “projection screen surface SS” means the surface of a member on which an image is projected. The “projection screen PS” means an area of an image projected on the projection screen surface SS by the projector 100. Usually, the projection screen PS is projected on a part of the projection screen surface SS. The projection screen surface SS is also referred to as an “operation surface SS” because it is also used as an operation surface for performing a position instruction by an indicator.

  The self-light emitting indicator 70 is a pen-type indicator having a tip portion 71 capable of emitting light, a shaft portion 72 held by a user, and a button switch 73 provided on the shaft portion 72. For example, the tip 71 of the self-luminous indicator 70 emits infrared light. The configuration and function of the self-luminous indicator 70 will be described later. In this system 900, one or a plurality of non-luminous indicators 80 (non-luminous pens, fingers, etc.) can be used together with one or a plurality of self-luminous indicators 70.

  3A is a front view of the position detection system 900, and FIG. 3B is a side view thereof. In this specification, the direction along the left and right of the operation surface SS is defined as the X direction, the direction along the top and bottom of the operation surface SS is defined as the Y direction, and the direction along the normal line of the operation surface SS is defined as the Z direction. It is defined as Further, the upper left position of the operation surface SS in FIG. 3A is the origin (0, 0) of the coordinates (X, Y). For convenience, the X direction is also referred to as “left-right direction”, the Y direction is also referred to as “up-down direction”, and the Z direction is also referred to as “front-rear direction”. Further, in the Y direction (up and down direction), a direction in which the projection screen PS exists when viewed from the projector 100 is referred to as a “down direction”. In FIG. 3B, for convenience of illustration, the range of the projection screen PS in the screen plate 920 is hatched.

  The projector 100 detects layers in the projection lens 210 that projects the projection screen PS onto the operation surface SS, the camera 310 that captures an area of the projection screen PS, and indicators (the self-luminous indicator 70 and the non-luminous indicator 80). And a layered detection light irradiation unit 440 for irradiating the light LL (FIG. 3B). The layered detection light irradiating unit 440 is layered (or curtained) over the entire surface of the projection screen PS in order to detect that the non-light emitting indicator 80 is in contact with the projection screen PS (that is, the operation surface SS). It is an irradiation part which inject | emits the detection light LL. In FIG. 3A, the irradiation range of the layered detection light LL is indicated by a one-dot chain line and an angle θ. The layered detection light irradiating unit 440 is installed above the upper end of the screen plate 920, and emits the layered detection light LL downward in the range of the angle θ. In the present embodiment, the angle θ is about 160 °. Thereby, the detection light LL is emitted over the entire surface of the projection screen PS. Note that the angle θ at which the layered detection light LL is emitted is not limited to the present embodiment, and may be an angle at which the layered detection light LL is emitted over the entire surface of the projection screen PS. For example, infrared light can be used as the layered detection light LL. Here, “layer” or “curtain” means a thin space shape having a substantially uniform thickness. The distance between the operation surface SS and the layered detection light LL is set to a value in the range of 1 to 10 mm (preferably 1 to 5 mm), for example.

  The camera 310 has at least a first imaging function for receiving and imaging light in a wavelength region including the layered detection light LL (infrared light) and the wavelength of infrared light emitted from the self-luminous indicator 70. The camera 310 further has a second imaging function for receiving and imaging light including visible light, and is preferably configured to be able to switch between these two imaging functions. For example, the camera 310 has a near-infrared filter switching mechanism capable of disposing a near-infrared filter that blocks visible light and allows only near-infrared light to pass in front of or behind the lens. (Not shown) are preferably provided.

  The example of FIG. 3A shows the position detection system 900 operating in the whiteboard mode. The whiteboard mode is a mode in which the user can arbitrarily draw on the projection screen PS using the self-light emitting indicator 70 and the non-light emitting indicator 80. A projection screen PS including a tool box TB is projected on the operation surface SS. This tool box TB selects a cancel button UDB for returning processing, a pointer button PTB for selecting a mouse pointer, a pen button PEB for selecting a pen tool for drawing, and an eraser tool for erasing a drawn image. It includes an eraser button ERB and a forward / backward button FRB that advances or moves the screen forward. The user can perform a process corresponding to the button or select a tool by clicking these buttons using an indicator. Note that the mouse pointer may be selected as the default tool immediately after the system 900 is activated. In the example of FIG. 3A, after the user selects the pen tool, the tip 71 of the self-luminous indicator 70 is moved in the projection screen PS while being in contact with the operation surface SS, thereby drawing a line in the projection screen PS. The state of being done is drawn. The line drawing is performed by a projection image generation unit (described later) inside the projector 100.

  Note that the position detection system 900 can also operate in modes other than the whiteboard mode. For example, the system 900 can also operate in a PC interactive mode in which an image of data transferred from a personal computer (not shown) via a communication line is displayed on the projection screen PS. In the PC interactive mode, for example, an image of data such as spreadsheet software is displayed, and it is possible to input, create, and correct data using various tools and icons displayed in the image. .

  FIG. 4 is a block diagram showing the internal configuration of the projector 100 and the self-luminous indicator 70. The projector 100 includes a control unit 700, a projection unit 200, a projection image generation unit 500, a position detection unit 600, an imaging unit 300, a signal light transmission / reception unit 430, and a layered detection light irradiation unit 440. Yes.

  The control unit 700 controls each unit in the projector 100. In addition, the control unit 700 determines the content of the instruction made on the projection screen PS according to the indication position of the indicator (self-luminous indicator 70 or non-luminous indicator 80) detected by the position detector 600. In addition, it instructs the projection image generation unit 500 to create or change the projection image according to the contents of the instruction. In addition, the control unit 700 includes a synchronization control unit 710 that synchronizes with other projectors 100.

  The projection image generation unit 500 includes a projection image memory 510 that stores the projection image, and has a function of generating a projection image projected on the operation surface SS by the projection unit 200. The projection image generation unit 500 preferably further has a function as a keystone correction unit that corrects the trapezoidal distortion of the projection screen PS (FIG. 3A).

  The projection unit 200 has a function of projecting the projection image generated by the projection image generation unit 500 onto the operation surface SS. The projection unit 200 includes a light modulation unit 220 and a light source 230 in addition to the projection lens 210 described with reference to FIG. 3B. The light modulator 220 modulates the light from the light source 230 according to the projection image data given from the projection image memory 510 to form the projection image light IML. The projection image light IML is typically color image light including three colors of visible light of RGB, and is projected onto the operation surface SS by the projection lens 210. As the light source 230, various light sources such as a light emitting diode and a laser diode can be adopted in addition to a light source lamp such as an ultra-high pressure mercury lamp. Further, as the light modulation unit 220, a transmissive or reflective liquid crystal panel, a digital mirror device, or the like can be adopted, and a configuration including a plurality of light modulation units 220 for each color light may be employed.

  The signal light transmission / reception unit 430 has a function of periodically transmitting device signal light ASL, which is a synchronization near-infrared light signal. The signal light receiving unit 74 of the self-luminous indicator 70 receives the device signal light ASL, and the tip light emitting unit 77 is a near-red light having a predetermined light emission pattern (light emission sequence) in synchronization with the device signal light ASL. An indicator signal light PSL (described later) that is external light is emitted. Further, the camera 310 of the imaging unit 300 executes imaging at a predetermined timing synchronized with the apparatus signal light ASL when detecting the indication position by the indicators (the self-luminous indicator 70 and the non-luminous indicator 80). The signal light transmission / reception unit 430 further has a function of receiving the device signal light ASL emitted from another projector 100. The projector 100 has a function of emitting its own synchronization signal (device signal light ASL) in synchronization with the other projectors 100.

  The imaging unit 300 includes the camera 310 described with reference to FIGS. 3A and 3B. As described above, the camera 310 has a function of receiving and imaging light in a wavelength region including the layered detection light LL and the wavelength of the infrared light emitted from the self-luminous indicator 70. In the example of FIG. 4, the layered detection light LL irradiated by the layered detection light irradiating unit 440 is reflected by the indicators (the self-emission indicator 70 and the non-emission indicator 80), and the reflected detection light RDL is received by the camera 310. The state of being captured is depicted. The camera 310 further receives and images indicator signal light PSL, which is near-infrared light emitted from the tip light emitting unit 77 of the self-emission indicator 70. Imaging by the camera 310 includes a first period in which the layered detection light LL emitted from the layered detection light irradiation unit 440 is in an on state (light emission state) and a second period in which the layered detection light LL is in an off state (non-light emission state). It is executed both in the period. The position detection unit 600 compares the images in these two types of periods, so that each indicator (bright spot) included in the image is either the self-luminous indicator 70 or the non-luminous indicator 80. Can be determined.

  The position detection unit 600 has a function of analyzing an image picked up by the camera 310 and determining an indication position by an indicator (self-luminous indicator 70 or non-luminous indicator 80). At this time, the position detection unit 600 uses the light emission pattern of the self-light-emitting indicator 70 to determine whether each indicator (bright spot) in the image is the self-light-emitting indicator 70 or the non-light-emitting indicator 80. Also determine.

  In addition to the button switch 73, the self light emitting indicator 70 is provided with a signal light receiving unit 74, a control unit 75, a tip switch 76, and a tip light emitting unit 77. The signal light receiving unit 74 has a function of receiving the device signal light ASL emitted from the signal light transmitting / receiving unit 430 of the projector 100. The tip switch 76 is a switch that is turned on when the tip 71 of the self-luminous indicator 70 is pressed and turned off when the tip 71 is released. The tip switch 76 is normally in an off state, and when the tip portion 71 of the self-luminous indicator 70 comes into contact with the operation surface SS, the tip switch 76 is turned on by the contact pressure. When the tip switch 76 is in the OFF state, the control unit 75 has the first light emission pattern by causing the tip light emitting unit 77 to emit light with a specific first light emission pattern indicating that the tip switch 76 is in the OFF state. The indicator signal light PSL is emitted. On the other hand, when the tip switch 76 is turned on, the control unit 75 causes the tip light emitting unit 77 to emit light with a specific second light emission pattern indicating that the tip switch 76 is turned on. The indicator signal light PSL having Since the first light emission pattern and the second light emission pattern are different from each other, the position detection unit 600 identifies whether the tip switch 76 is in the on state or the off state by analyzing the image captured by the camera 310. Is possible.

  The button switch 73 of the self-luminous indicator 70 has the same function as the tip switch 76. Accordingly, the control unit 75 causes the tip light emitting unit 77 to emit light with the second light emission pattern when the button switch 73 is pressed by the user, and uses the first light emission pattern when the button switch 73 is not pressed. The tip light emitting unit 77 emits light. In other words, the control unit 75 causes the tip light emitting unit 77 to emit light with the second light emission pattern when at least one of the tip switch 76 and the button switch 73 is on, and both the tip switch 76 and the button switch 73 are off. In this state, the tip light emitting portion 77 is caused to emit light with the first light emission pattern.

  However, a function different from the tip switch 76 may be assigned to the button switch 73. For example, when the same function as that of the right click button of the mouse is assigned to the button switch 73, when the user presses the button switch 73, a right click instruction is transmitted to the control unit 700 of the projector 100, and the instruction is received. A corresponding process is executed. As described above, when a function different from that of the tip switch 76 is assigned to the button switch 73, the tip light emitting unit 77 depends on the on / off state of the tip switch 76 and the on / off state of the button switch 73. Light is emitted with four different light emission patterns. In this case, the self-luminous indicator 70 can transmit to the projector 100 while distinguishing the four combinations of the on / off states of the tip switch 76 and the button switch 73.

The specific examples of the five types of signal light depicted in FIG. 4 are summarized as follows.
(1) Projected image light IML: Image light (visible light) projected on the operation surface SS by the projection lens 210 in order to project the projection screen PS on the operation surface SS.
(2) Layered detection light LL: Curtain-like near-infrared light that is irradiated over the entire surface of the projection screen PS in order to detect the indicated position of the non-light emitting indicator 80.
(3) Reflected detection light RDL: Near-red light reflected by the indicators (self-luminous indicator 70 and non-luminous indicator 80) of the near-infrared light emitted as the layered detection light LL and received by the camera 310 It is outside light.
(4) Device signal light ASL: Near-infrared light periodically emitted from the signal light transmitting / receiving unit 430 of the projector 100 in order to synchronize the projector 100 and the self-luminous indicator 70.
(5) Indicator signal light PSL: Near-infrared light emitted from the tip light emitting part 77 of the self-emission indicator 70 at a timing synchronized with the device signal light ASL. The light emission pattern of the indicator signal light PSL is changed according to the on / off state of the button switches 73 and 76 of the self-light emission indicator 70. Further, it has a unique light emission pattern for identifying the plurality of self-light emitting indicators 70.

  FIG. 5 is an explanatory diagram showing how the two projectors 100a and 100b operate in synchronization. In the following description, when the two projectors 100a and 100b are not distinguished from each other, the explanation will be made by omitting “a” and “b” at the end of the reference numerals. The projector 100 includes a single mode that operates independently and a synchronous mode that operates in synchronization with the other projectors 100. When operating in the synchronous mode, one projector 100 operates as a master (main), and the other projectors 100 operate as slaves (slave). Whether each projector 100 operates as a master or a slave is determined based on the apparatus signal light ASL. For example, when the projector 100a is activated first and the projector 100b is activated later, the signal light transmission / reception unit 430b of the projector 100b activated later receives the apparatus signal light ASLa of the projector 100a immediately after the activation. Determines itself as a slave. The control unit 700b of the projector 100b transmits the apparatus signal light ASLb from the signal light transmission / reception unit 430b at the same timing as the transmission timing of the apparatus signal light ASLa of the projector 100a. The operation of the master projector 100a is the same as the operation in the single mode.

  As described above, in each projector 100, the layered detection light LL is emitted in synchronization with its own apparatus signal light ASL, and imaging by the imaging unit 300 is performed. In FIG. 5, the layered detection light LLa and LLb irradiated by the layered detection light irradiation units 440a and 440b are reflected by the indicators (the self-light emitting indicator 70 and the non-light emitting indicator 80), and the reflected detection lights RDLa and RDLb thereof. Is depicted as being received and imaged by the imaging unit 300a.

  As shown in FIG. 1, in the wide area position detection system 1000, two projection screen surfaces SSa and SSb are arranged side by side so as to be adjacent to each other. Therefore, the layered detection light LLa (indicated by a one-dot chain line in FIG. 1) emitted by the projector 100a and the layered detection light LLb (indicated by a two-dot chain line in FIG. 1) emitted by the projector 100b partially overlap. .

  If two layered detection lights LLa and LLb are simultaneously irradiated onto the non-light emitting indicator 80, two reflected lights (reflected detection lights RDLa and RDLb in FIG. 5) are generated. Since the two layered detection lights LLa and LLb are applied to the non-light emitting indicator 80 from different directions, the reflection positions of the reflected detection lights RDLa and RDLb do not completely match. Therefore, the bright spot included in the captured image captured by the imaging unit 300a becomes large and unclear. If it does so, the detection accuracy of the indication position by the non-light emission indicator 80 in the projector 100 will fall. Therefore, in the wide-area position detection system 1000 according to the present embodiment, the two layered detection lights LLa and LLb are irradiated at different timings in order to suppress a decrease in position detection accuracy (detailed later).

  The master projector 100a emits the layered detection light LLa at the same timing as in the single mode, and performs imaging by the imaging unit 300a. On the other hand, the projector 100b that has become a slave performs emission of the layered detection light LLb and imaging by the imaging unit 300b at timings different from those of the projector 100a (described later). That is, the two projectors 100a and 100b are different from each other in the emission and imaging timing of the layered detection light LL after the device signal light ASL is emitted.

  In the present embodiment, the projector 100a is the “first position detection device”, the projection screen surface SSa is the “first operation surface”, the layered detection light LLa is the “first detection light”, and the layered detection light irradiation unit 440a is “ The “first irradiating unit”, the imaging unit 300a is also referred to as “first imaging unit”, the position detection unit 600a is also referred to as “first detection unit”, and the control unit 700a is also referred to as “first control unit”. In addition, the projector 100b is a “second position detection device”, the projection screen surface SSb is a “second operation surface”, the layered detection light LLb is “second detection light”, and the layered detection light irradiation unit 440b is “second”. The imaging unit 300b is also referred to as a “second imaging unit”, the position detection unit 600b is also referred to as a “second detection unit”, and the control unit 700b is also referred to as a “second control unit”. Further, the tip light emitting unit 77 of the self-light emitting indicator 70 is also referred to as “light emitting unit”, and the control unit 75 is also referred to as “light emission control unit”.

  FIG. 6 is a timing chart showing the light emission timing and imaging timing of the layered detection light LL and the indicator signal light PSL in the wide area position detection system 1000. In the wide-area position detection system 1000 according to the present embodiment, position detection of indicators (self-emission indicator 70, non-emission indicator 80) is performed according to the sequence shown in FIG. FIG. 6 illustrates the first phase PH1 to the fourth phase PH4. In this embodiment, the first phase PH1 to the fourth phase PH4 are set as one cycle, and the pointing position is specified by distinguishing the self-light emitting indicator 70 and the non-light emitting indicator 80.

  The apparatus signal lights ASLa and ASLb are transmitted from the two projectors 100a and 100b at the same timing at the head of the first phase PH1. In the second phase PH2 and the fourth phase PH4, the master projector 100a emits the layered detection light LLa and performs imaging with the imaging unit 300a (imaging period in FIG. 6). Similarly, in the second phase PH2 and the fourth phase PH4, the slave projector 100b emits the layered detection light LLb and performs imaging with the imaging unit 300b. However, the emission timings of the layered detection lights LLa and LLb are different from each other. The light emission periods of the two layered detection lights LLa and LLb are shown side by side at the bottom of FIG. In the example of FIG. 6, the first irradiation period (simply referred to as “irradiation period”) of the layered detection light LLa and the second irradiation period (simply referred to as “irradiation period”) of the layered detection light LLb do not overlap.

  FIG. 7A is an explanatory diagram of an irradiation range of the layered detection light LLa, and FIG. 7B is an explanatory diagram of an irradiation range of the layered detection light LLb. In the example shown in FIG. 6, the irradiation periods of the two layered detection lights LLa and LLb do not overlap. Therefore, in the second phase PH2 and the fourth phase PH4, only the layered detection light LLa is irradiated (FIG. 7A), and then only the layered detection light LLb is irradiated (FIG. 7B). Therefore, there is no period in which the irradiation ranges of the two layered detection lights LL overlap.

  The indicator signal light PSL (FIG. 6) is emitted in the second phase PH2 to the fourth phase PH4 in synchronization with the device signal light ASL. As described above, the apparatus signal light ASLb is emitted in accordance with the apparatus signal light ASLa. Therefore, the self-emission indicator 70 is placed on the projection screen surface SSa or the projection screen surface SSb at the same timing. Emits light.

  It is preferable that the first imaging period CTa of the projector 100a includes the entire irradiation period of the layered detection light LLa. Here, since the irradiation period of the layered detection light LLa includes the light emission period of the indicator signal light PSL, the first imaging period CTa of the projector 100a is the light emission period of the layered detection light LLa and the light emission of the indicator signal light PSL. Including period. The second imaging period CTb of the projector 100b preferably includes the entire irradiation period of the layered detection light LLb and the light emission period of the indicator signal light PSL. That is, the first imaging period CTa and the second imaging period CTb partially overlap, and the indicator signal light PSL is emitted from the tip light emitting unit 77 of the self-emission indicator 70 during the overlapping imaging period OCT. Therefore, even when the self-luminous indicator 70 is on either of the two projection screen surfaces SSa and SSb, the indicated position can be detected.

  As described above, according to the wide area position detection system 1000 of the present embodiment, the layered detection lights LLa and LLb of the two projectors 100a and 100b are irradiated at different timings, and the two layered detection lights LLa and LLb are irradiated. There are no overlapping periods. Therefore, the two layered detection lights LLa and LLb are not simultaneously irradiated from different directions to the non-light emitting indicator 80. As a result, the bright spot of the reflected light by the non-light emitting indicator 80 in the captured image by the imaging unit 300 becomes smaller than the bright spot formed by the two reflected lights, and the detection accuracy of the indicated position is improved.

・ Other examples:
FIG. 8 is a timing chart showing another example of the light emission timing and imaging timing of the layered detection light LL and the indicator signal light PSL in the wide area position detection system 1000. In the example shown in FIG. 8, although the irradiation period and irradiation timing of the layered detection light LL are different from the example shown in FIG. 6, the imaging timing and the imaging period and the emission timing of the indicator signal light PSL are shown in FIG. Same as example.

  In this example, the irradiation period of the layered detection light LLa in the projector 100a coincides with the imaging period and the imaging timing of the imaging unit 300a, and the irradiation period of the layered detection light LLb in the projector 100b is the imaging period and the imaging timing of the imaging unit 300b. Matches. As shown in the lowermost stage of FIG. 8, a part of the first irradiation period of the layered detection light LLa of the projector 100a and the second irradiation period of the layered detection light LLb of the projector 100b overlap. The overlapped irradiation period in which the first irradiation period of the layered detection light LLa and the second irradiation period of the layered detection light LLLb overlap is preferably 50% or less of the irradiation period of the layered detection light LLa, and the example of FIG. Then, it is about 30%.

  In this example, although the irradiation periods of the two layered detection lights LLa and LLb partially overlap, the irradiation timings of the two layered detection lights LLa and LLb are different. Therefore, the period during which the two layered detection lights LLa and LLb are simultaneously irradiated from different directions with respect to the non-light emitting indicator 80 is shortened compared to the case where the two layered detection lights LLa and LLb are irradiated at the same timing. Is done. Therefore, the bright spot of the reflected light by the non-light emitting indicator 80 in the image captured by the imaging unit 300 becomes clearer than when the two layered detection lights LLa and LLb are irradiated at the same timing, and the indication position is detected. Accuracy is improved.

  In addition, since the overlapping irradiation period in which the irradiation periods of the two layered detection lights LLa and LLb overlap is as short as 50% or less of the irradiation period of the layered detection light LLa, the influence of the two reflected lights on the detection of the indicated position is suppressed. can do.

B. Second embodiment:
FIG. 9 is a front view showing a schematic configuration of a wide area position detection system 1000A as the second embodiment. The difference between the position detection system 900A of the present embodiment and the first embodiment is that the projector 100A of the first position detection systems 900aA and 900bA is detected in place of the layered detection light irradiation unit 440 in the projector 100 of the first embodiment. In addition to the point provided with the light irradiation unit 410 and the camera 310 (referred to as the first camera 310 in the present embodiment) in the projector 100 of the first embodiment, the second camera 320 is provided. The same as in the first embodiment.

  FIG. 10 is a perspective view of a position detection system 900A according to the second embodiment, and FIG. 11 is a side view thereof. The projector 100A according to the present embodiment uses the images captured by the two cameras 310 and 320 and uses the triangulation to three-dimensional the tip of the indicator (the self-luminous indicator 70 or the non-luminous indicator 80). Has the function of determining the position.

  As shown in FIG. 11, the detection light irradiation unit 410 generates irradiation detection light IDL for detecting the tip of the indicators (the self-luminous indicator 70 and the non-luminous indicator 80) and the projection screen surface SS and the front thereof. Irradiate over space. As the irradiation detection light IDL, near infrared light is used as in the first embodiment. As shown in FIGS. 9 and 11, the irradiation detection light IDL is irradiated over the entire surface of the projection screen PS. Thereby, all indication positions on the projection screen PS by the non-light emission indicator 80 can be detected. Since the two projection screen surfaces SSa and SSb are arranged adjacent to each other, the irradiation detection light IDLa (indicated by a one-dot chain line in FIG. 9) and the irradiation detection light IDLb (indicated by a two-dot chain line in FIG. 9) are: Part of the irradiation range overlaps. Therefore, the two irradiation detection lights IDLa and IDLb are irradiated at the same timing as the two layered detection lights LLa and LLb in the first embodiment, respectively. Thereby, the fall of the detection accuracy of the indication position by a non-light emission indicator is suppressed.

  In the present embodiment, the irradiation detection light IDLa is also referred to as “first detection light”, and the detection light irradiation unit 410a is also referred to as “first irradiation unit”. The irradiation detection light IDLb is also referred to as “second detection light”, and the detection light irradiation unit 410b is also referred to as “second irradiation unit”.

  The two cameras 310 and 320 have at least a first imaging function for receiving and imaging light in a wavelength region including the wavelength of detection light. At least one of the two cameras 310 and 320 further has a second imaging function for receiving and imaging light including visible light, and is configured to be able to switch between these two imaging functions. Is preferred. For example, in the two cameras 310 and 320, a near-infrared filter that blocks visible light and allows only near-infrared light to pass can be arranged in front of the lens or moved backward from the front of the lens. An infrared filter switching mechanism (not shown) is preferably provided.

  FIG. 12 is a block diagram illustrating an internal configuration of the projector 100A according to the second embodiment. The difference from FIG. 4 is that the imaging unit 300A mainly includes two cameras (first camera 310 and second camera 320) and a detection light irradiation unit 410 instead of the layered detection light irradiation unit 440. The other configurations are almost the same as those in FIG.

  The imaging unit 300 includes a first camera 310 and a second camera 320. As described above, the two cameras 310 and 320 have a function of receiving and imaging light in a wavelength region including the wavelength of the detection light. In the example of FIG. 12, the irradiation detection light IDL irradiated by the detection light irradiation unit 410 is reflected by the indicators (the self-emission indicator 70 and the non-emission indicator 80), and the reflected detection light RDL is reflected by the two cameras 310. , 320 are received and imaged. The two cameras 310 and 320 also receive and image indicator signal light PSL, which is near-infrared light emitted from the tip light emitting unit 77 of the self-emission indicator 70. The two cameras 310 and 320 are imaged in a first period in which the irradiation detection light IDL emitted from the detection light irradiation unit 410 is on (light emission state) and the irradiation detection light IDL is off (non-light emission state). It is executed both in the second period. The position detection unit 600 determines whether each indicator included in the image is the self-emission indicator 70 or the non-emission indicator 80 by comparing the images in these two types of periods. It is possible.

  Note that at least one of the two cameras 310 and 320 preferably has a function of capturing an image using light including visible light in addition to a function of capturing an image using light including near infrared light. In this way, the projection screen PS projected on the projection screen surface SS can be captured by the camera, and the projection image generation unit 500 can execute keystone correction using the image. Since the keystone correction method using one or more cameras is well known, the description thereof is omitted here.

  The position detection unit 600 uses the images captured by the two cameras 310 and 320 and uses the triangulation to determine the three-dimensional position of the tip of the indicator (the self-emission indicator 70 or the non-emission indicator 80). Has a function to determine. In the case of the self-luminous indicator 70, the indicator signal light PSL emitted from the tip light emitting portion 77 disposed at the tip portion 71 of the self-luminous indicator 70 is included in the captured image. For this reason, the three-dimensional position of the tip 71 of the self-luminous indicator 70 is calculated according to triangulation based on the bright spot included in the captured image.

  On the other hand, in the case of the non-light emitting indicator 80, the reflected detection light RDL reflected by the non-light emitting indicator 80 is included in the captured image. The position of the tip of the non-light emitting indicator 80 in the two images captured by the two cameras 310 and 320 can be determined using a known technique such as template matching or feature extraction. For example, when recognizing the tip of the non-light emitting indicator 80, which is a finger, by template matching, a plurality of templates relating to the finger are prepared in advance and these images are captured by the two cameras 310 and 320. It is possible to recognize the tip of the finger by searching for a part that matches the template. The three-dimensional position of the tip of the non-light emitting indicator 80 is calculated according to triangulation based on the tip recognized by template matching or the like.

  As described above, also in the wide area position detection system 1000A of the second embodiment, similarly to the first embodiment, by irradiating the two irradiation detection lights IDL at different timings, A decrease in detection accuracy can be suppressed.

・ Modification:
The present invention is not limited to the above-described examples and embodiments, and can be implemented in various modes without departing from the gist thereof. For example, the following modifications are possible.

・ Modification 1:
In the above embodiment, an interactive projector has been described as an example of a position detection device. However, the present invention can also be applied to other position detection devices other than the interactive projector. For example, the present invention can be applied to a digitizer or a tablet that indicates a position on the operation surface using an indicator. Further, a position detection device using a flat panel display or the like that displays an image on an image display unit such as a liquid crystal panel, an organic EL panel, or a plasma display panel (PDP) as an operation surface may be used.

Modification 2
In the above embodiment, an example in which two position detection systems 900 are arranged side by side has been described. However, three or more position detection systems 900 may be arranged side by side. When three or more position detection systems 900 are arranged, at least two adjacent projectors 100 may be configured to irradiate the layered detection light LL or the irradiation detection light IDL at different timings.

・ Modification 3:
In the above embodiment, an example in which the irradiation periods of the layered detection lights LLa and LLb do not overlap (FIG. 6) and an example in which the overlapping irradiation period overlaps 50% or less of the irradiation period of the layered detection light LLa are shown. However, the overlapping irradiation period is not limited to these examples, and the two layered detection lights LLa and LLb may be irradiated at different timings. However, the detection accuracy of the indicated position is improved as the overlapping irradiation period in which the irradiation periods of the two layered detection lights LLa and LLb overlap is shorter. For example, the overlapping irradiation period is preferably 50% or less of the irradiation period of the layered detection light LLa, more preferably 30% or less, and most preferably the irradiation periods of the two layered detection lights LLa and LLb do not overlap. However, on the operation surface SS, the detection light becomes weaker at a position far from the layered detection light irradiation unit 440 or the detection light irradiation unit 410 as compared with a close position. In order to enable detection, it is preferable to make the irradiation period of the detection light relatively long. Therefore, the overlapping irradiation period may be determined according to the intensity of the detection light. In addition, the overlapping irradiation period may be determined according to the distance between the layered detection light irradiation unit 440, the detection light irradiation unit 410, and the operation surface SS.

-Modification 4:
In the above-described embodiment, the wide-area position detection system 1000 that can detect the indication positions of both the self-luminous indicator 70 and the non-luminous indicator 80 has been exemplified. Good.

-Modification 5:
In the above embodiment, an example in which a part of the imaging period of the projector 100a and the projector 100b overlaps is shown, but the whole imaging period of the projector 100a and the projector 100b may overlap. For example, the imaging period may be set so as to include both the irradiation period of the layered detection light LLa and the irradiation period of the layered detection light LLb. In the example shown in FIG. 6, the entire second phase period may be set as the imaging period. The same applies to the third and fourth phases.

  The embodiments of the present invention have been described above based on some examples. However, the above-described embodiments of the present invention are for facilitating the understanding of the present invention and limit the present invention. It is not a thing. The present invention can be changed and improved without departing from the spirit and scope of the claims, and it is needless to say that the present invention includes equivalents thereof.

  DESCRIPTION OF SYMBOLS 70 ... Self-luminous indicator, 71 ... Tip part, 72 ... Shaft part, 73 ... Button switch, 74 ... Signal light receiving part, 75 ... Control part, 76 ... Tip switch, 77 ... Tip light emission part, 80 ... Non-light emission instruction Body 100 ... Interactive projector (projector) 100A Projector 100a Projector 100b Projector 200 Projector 210 Projector lens 220 Light modulator 230 Light source 300 Imager 300A Imager , 300a ... Imaging unit, 300b ... Imaging unit, 310 ... Camera (first camera), 320 ... Second camera, 410 ... Detection light irradiation unit, 430 ... Signal light transmission / reception unit, 430a ... Signal light transmission / reception unit, 430b ... Signal light transmission / reception unit, 440 ... layered detection light irradiation unit, 440a ... layered detection light irradiation unit, 440b ... layered detection light irradiation unit, 5 DESCRIPTION OF SYMBOLS 0 ... Projection image generation part, 510 ... Projection image memory, 600 ... Position detection part, 700 ... Control part, 700a ... Control part, 700b ... Control part, 710 ... Synchronization control part, 900 ... Position detection system, 900A ... position detection system, 900a ... first position detection system, 900aA ... first position detection system, 900b ... second position detection system, 900bA ... second position detection system, 910 ... support member, 920 ... screen Plate, 1000A ... Wide area position detection system, 1000 ... Wide area position detection system, ASL ... Device signal light, ASLa ... Device signal light, ASLb ... Device signal light, ERB ... Eraser button, FRB ... Front / rear button, IDL ... Irradiation detection Light, IDLa ... irradiation detection light, IDLb ... irradiation detection light, IML ... projection image light, LL ... layered detection light, L a ... layer detection light, LLb ... layer detection light, PEB ... pen button, PS ... projection screen, PSL ... indicator signal light, PTB ... pointer button, RDL ... reflection detection light, RDLa ... reflection detection light, RDLb ... reflection detection Light, SS ... Projection screen surface (operation surface), SSa ... Projection screen surface, SSb ... Projection screen surface, TB ... Tool box, UDB ... Cancel button

Claims (6)

A position comprising: a first position detection device that detects a position on a first operation surface; and a second position detection device that detects a position on a second operation surface adjacent to the first operation surface. A detection system,
The first position detection device includes:
A first irradiating unit that periodically irradiates a first detection light for detecting a first indication position indicated by a non-luminous indicator on the first operation surface;
A first imaging unit that receives light in a wavelength region including a wavelength of the first detection light, images the first operation surface, and generates a first captured image;
A first detector that detects the first designated position based on the first captured image;
A first control unit for controlling the irradiation timing of the first detection light by the first irradiation unit,
The second position detection device includes:
A second irradiating unit that periodically irradiates a second detection light for detecting a second designated position designated using the non-light emitting indicator on the second operation surface;
A second imaging unit that receives light in a wavelength region including the wavelength of the second detection light, images the second operation surface, and generates a second captured image;
A second detector for detecting the second designated position based on the second captured image;
A second control unit that controls the second irradiation unit so that the second detection light is irradiated at a timing different from the irradiation timing of the first detection light;
A position detection system comprising: The position detection system according to claim 1.
The second control unit of the second position detection device is
A first irradiation period in which the first detection light of the first position detection device is irradiated and a second irradiation period in which the second detection light of the second position detection device is irradiated Controlling the second irradiating unit so that the second detection light is irradiated at a timing such that a part thereof overlaps;
The overlapping detection period in which the first irradiation period and the second irradiation period overlap is 50% or less of the first irradiation period. The position detection system according to claim 1 or 2,
further,
A self-emission indicator having a light emitting unit that periodically emits light and a light emission control unit that controls the light emission timing of the light emitting unit,
In the position detection system,
The first imaging period captured by the first imaging unit and the second imaging period captured by the second imaging unit at least partially overlap,
The light emission control unit of the self-luminous indicator is
The position detection system which controls so that the said light emission part light-emits in the overlapping imaging period in which a said 1st imaging period and a said 2nd imaging period overlap. The position detection system according to any one of claims 1 to 3,
The first position detection device includes:
A first projection unit that projects an image on the first operation surface;
The second position detection device includes:
A position detection system further comprising a second projection unit that projects an image on the second operation surface. A position detection device for detecting a position on an operation surface,
A synchronization control unit that synchronizes with another position detection device that detects a position on another operation surface adjacent to the operation surface;
An irradiating unit for periodically irradiating detection light for detecting an indication position indicated by a non-luminous indicator on the operation surface;
An imaging unit that receives light in a wavelength region including the wavelength of the detection light, images the operation surface, and generates a captured image;
A detection unit that detects the indicated position based on the captured image;
When used in synchronization with the other position detection device, the irradiation timing of the irradiation unit is set so that the detection light of the other position detection device is irradiated at a timing different from the timing at which the other position detection device irradiates the detection light. A control unit to control;
A position detection device comprising: A position comprising: a first position detection device that detects a position on a first operation surface; and a second position detection device that detects a position on a second operation surface adjacent to the first operation surface. A method for detecting an indication position indicated by a non-light emitting indicator on the first operation surface or the second operation surface using a detection system,
As detection light for detecting the indicated position, the first detection light emitted by the first position detection device and the second detection light emitted by the second position detection device are at different timings. Irradiating periodically,
Receiving light in a wavelength region including wavelengths of the first detection light and the second detection light, capturing the first operation surface and the second operation surface, and generating a captured image;
Detecting the indicated position based on the captured image;
A position detection method comprising:

Images