JP2017142726A - Electronic blackboard system, display device, and display method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To display, when a plurality of electronic pens are used for an electronic blackboard system, operations with the plurality of electronic pens in an identifiable manner with a simple configuration.SOLUTION: There is provided a projector 20 that projects and displays a display image, the projector 20 photographing an imaging area 52, detecting positions of operation with a plurality of electronic pens that emit light with wavelengths different from each other, for each of the plurality of electronic pens with each of the wavelengths emitted from the electronic pens, recognizing, in a PC 10, the details of the operations with the electronic pens for each of the plurality of electronic pens on the basis of the detected operation positions and functions set respectively to the plurality of electronic pens, and displaying a display image according to the recognized details of the operations.SELECTED DRAWING: Figure 1

Description

  The present invention relates to an electronic blackboard system using an electronic pen, and more particularly, to a technology that makes it possible to identify operations performed by a plurality of electronic pens when a plurality of electronic pens are used.

2. Description of the Related Art In recent years, an electronic blackboard system has been used in which when an electronic pen is operated on a screen on which a display image is displayed by a projector or the like, an operation image by the electronic pen is combined with the display image and displayed. The mainstream of electronic blackboard systems using projectors is that infrared light is emitted from the pen tip when the electronic pen is pressed, and this infrared light is acquired by a camera such as a CMOS image sensor. It is a detected method.
In recent years, a so-called “multi-touch (pen) system” that uses a plurality of electronic pens to support simultaneous operation by the plurality of electronic pens has become the mainstream. However, since it is difficult to identify a plurality of electronic pens in a multi-touch system, it is difficult to assign different functions such as different display colors for each of the plurality of electronic pens.

  Therefore, a technique for identifying a plurality of electronic pens by providing a predetermined standby time as necessary when transferring data between a display device such as a projector and a plurality of electronic pens has been considered. It is disclosed in Patent Document 1.

JP 2011-145762 A

However, the technique disclosed in Patent Document 1 provides a predetermined waiting time as necessary when data is transferred between the display device and the electronic pen, and thus the algorithm becomes complicated. There is a point.
The present invention has been made in view of the above-described problems, and when a plurality of electronic pens are used in an electronic blackboard system, operations with the plurality of electronic pens can be identified with a simple configuration. An object is to provide an electronic blackboard system and a display method.

In order to achieve the above object, the present invention provides:
A plurality of electronic pens that emit light of different wavelengths;
A light detection unit that images an imaging area and detects light emitted from the electronic pen by distinguishing the plurality of electronic pens according to the wavelength of the light; and
A position detection unit that detects an operation position of the electronic pen for each of the plurality of electronic pens based on a position in the imaging area of the light detected by the light detection unit;
A recognition unit for recognizing the content of the operation by the electronic pen for each of the plurality of electronic pens based on the operation position detected by the position detection unit and the function set for each of the plurality of electronic pens;
An image generation unit that generates and outputs a video signal according to the content of the operation recognized by the recognition unit;
A display unit that displays a display image corresponding to the video signal output from the image generation unit.
A display device including an electronic pen,
The electronic pen emits light of different wavelengths,
The display device
A light detection unit that images an imaging area and detects light emitted from the electronic pen by distinguishing the plurality of electronic pens according to the wavelength of the light; and
A position detection unit that detects an operation position of the electronic pen for each of the plurality of electronic pens based on a position in the imaging area of the light detected by the light detection unit;
Display according to the content of the operation with the electronic pen recognized for each of the plurality of electronic pens based on the operation position detected by the position detection unit and the function set for each of the plurality of electronic pens And a display unit for displaying an image.
Also, a display image display method in an electronic blackboard system in which a plurality of electronic pens that emit light of different wavelengths is operated,
A light detection process for picking up an imaging area and detecting the light emitted from the electronic pen by distinguishing the plurality of electronic pens according to the wavelength of the light; and
A position detection process for detecting an operation position of the electronic pen for each of the plurality of electronic pens based on a position of the light detected in the light detection process in the imaging area;
A recognition process for recognizing the operation content of the electronic pen for each of the plurality of electronic pens based on the operation position detected in the position detection process and the function set for each of the plurality of electronic pens;
Display processing for generating a video signal corresponding to the content of the operation recognized in the recognition processing and displaying a display image corresponding to the video signal.

  According to the present invention, when a plurality of electronic pens are used in the electronic blackboard system, operations by the plurality of electronic pens can be identified with a simple configuration.

BRIEF DESCRIPTION OF THE DRAWINGS It is a figure which shows one Embodiment of the electronic blackboard system of this invention, (a) is a figure which shows the whole structure, (b) is an external appearance perspective view of the projector shown to (a). FIG. 2 is a block diagram illustrating a configuration example of a PC and a projector illustrated in FIG. 1. FIG. 3 is a diagram illustrating a detailed configuration of the camera unit illustrated in FIG. 2, in which (a) is a cross-sectional view, (b) is a diagram illustrating a configuration of an optical filter wheel, and (c) and (d) are configurations of a photointerplater. It is a figure for demonstrating operation | movement. It is a figure which shows the structural example of the electronic pen used for the electronic blackboard system shown in FIGS. It is a flowchart for demonstrating the display method of the display image in the electronic blackboard system shown in FIGS. It is a figure which shows the permeation | transmission characteristic of the optical filter shown in FIG. It is a figure which shows the example of the display image displayed on a screen. It is a figure which shows the example of the test pattern used in order to adjust correlation between the display image currently projected with the projector, and the image taken in with the camera unit.

Embodiments of the present invention will be described below with reference to the drawings.
1A and 1B are diagrams showing an embodiment of an electronic blackboard system according to the present invention. FIG. 1A is a diagram showing an overall configuration, and FIG. 1B is an external perspective view of a projector 20 shown in FIG. .
The electronic blackboard system according to the present embodiment includes a PC 10 and a projector 20 as shown in FIG.
The projector 20 serves as a display device, and is connected to the PC 10 via the cable 17 and includes a projection lens 40 and a camera unit 30. The projector 20 receives the video signal output from the PC 10 via the cable 17 and projects a display image corresponding to the received video signal onto the projection area 51 via the projection lens 40 and displays it on the screen 50. Further, the projector 20 images the imaging area 52 including the screen 50 by the camera unit 30 and detects the operation position of the electronic pen operated on the screen 50 for each of a plurality of preset electronic pens.
The PC 10 serves as a control device, and generates and outputs a video signal for displaying a display image on the screen 50. Further, the PC 10 recognizes the operation content of the electronic pen for each of the plurality of electronic pens based on the operation position of the electronic pen detected by the projector 20 and the function set for each of the plurality of electronic pens. A video signal corresponding to the content of the operation is generated and transmitted to the projector 20.

  In the electronic blackboard system configured as described above, in a state where a display image corresponding to the video signal output from the PC 10 is displayed on the screen 50, for example, on the screen 50 by a preset electronic pen. When an operation for writing information to the display image is performed, the written information is combined with the display image and displayed on the screen 50. Further, when the electronic pen functions as a mouse, when an icon in the display image is designated by the electronic pen, the display image changes according to the designated icon. As described above, when the electronic pen is operated on the screen 50 in a state where the display image is displayed on the screen 50, a display image corresponding to the operation content is displayed on the screen 50.

FIG. 2 is a block diagram illustrating a configuration example of the PC 10 and the projector 20 illustrated in FIG. 3 is a diagram showing a detailed configuration of the camera unit 30 shown in FIG. 2, (a) is a cross-sectional view, (b) is a diagram showing a configuration of the optical filter wheel 37, and (c), (d). FIG. 5 is a diagram for explaining the configuration and operation of a photointerpreter 33;
As shown in FIG. 2, the projector 20 in this example includes an interface unit 21, a CPU 22, a camera unit 30, and a projection unit 41.
The interface unit 21 transmits and receives information and signals to and from the PC 10 via the cable 17.
The CPU 22 includes a display control unit 25, a light distinction detection unit 23, and a position detection unit 24. The display control unit 25 constitutes a display unit together with the projection unit 41, and displays a display image corresponding to the video signal received from the PC 10 via the interface unit 21 via the projection unit 41. And is displayed on the screen 50. The light distinction detection unit 23 constitutes a light detection unit together with the camera unit 30, and detects infrared light emitted from the electronic pen in the imaging area captured by the camera unit 30. At that time, as will be described later, a plurality of electronic pens having different wavelengths of emitted infrared light are set as electronic pens operated on the screen 50, and the light discrimination detection unit 23 serves as a discrimination unit. The detected infrared light is detected for each of the plurality of electronic pens according to the wavelength. The position detection unit 24 detects the coordinates of the operation position of the electronic pen for each of the plurality of electronic pens based on the position of the infrared light detected by the light distinction detection unit 23 in the imaging area.
The projection unit 41 includes the projection lens 40 illustrated in FIG. 1 and projects the display image output from the display control unit 25 onto the projection area 51.

As shown in FIGS. 2 and 3, the camera unit 30 has a CMOS image sensor 31, a lens 36, a wheel motor 32, an optical filter wheel 37, and a photointerpreter 33 in a housing 38. Configured.
The casing 38 is provided with an infrared capturing window 39 serving as a window portion, and the imaging area 52 is imaged by the CMOS image sensor 31 through the infrared capturing window 39 to be emitted from the electronic pen. Infrared light is captured.
The CMOS image sensor 31 serves as a light receiving unit, is attached on the substrate 35 so as to face the infrared capturing window 39, and images the imaging area 52 via the lens 36. An optical filter wheel 37 is disposed between the lens 36 and the infrared capturing window 39. The optical filter wheel 37 has a wheel shape and rotates with the rotation of the wheel motor 32 attached to the center thereof. The optical filter wheel 37 has two types of optical filters 37a and 37b that are arranged side by side in the rotation direction of the optical filter wheel 37 and transmit infrared light of different wavelengths, and the optical filters 37a and 37b are alternately arranged. Are arranged so as to face the infrared capturing window 39. The optical filters 37a and 37 serve as a light transmission part.
A reflective seal 32 a serving as an identification mark is attached to a part of the outer peripheral surface of the wheel motor 32. The outer peripheral surface of the wheel motor 32 and the reflective seal 32a have different light reflectivities. Here, in this embodiment, the wheel motor 32 is composed of a member that absorbs most of the light components without reflecting, and the reflection seal 32a is composed of a member that reflects most of the light components. And The reflection seal 32a is affixed to one point of the boundary between the optical filters 37a and 37b on the outer peripheral surface of the wheel motor 32. The reflection seal 32 a is attached to the outer peripheral surface of the wheel motor 32, and moves with the rotation of the optical filter wheel 37.

  The photo interrupter 33 is for detecting the rotation period and timing of the optical filter wheel 37, and has a light emitting element 33a and a light receiving element 33b. For example, when a voltage is supplied, the light emitting element 33a emits light having a predetermined brightness toward the wheel motor 32. That is, the light emitted from the light emitting element 33a intersects the locus of the rotation trajectory along which the identification mark 32a moves at one point. However, the crossing position is not limited to one place, and a plurality of positions may be used. The light receiving element 33b receives the light reflected from the outer peripheral surface of the wheel motor 32 or the reflection seal 32a as the light emitted from the light emitting element 33a, and has a received light intensity that is an intensity corresponding to the brightness of the received light. A corresponding signal is output as a rotation detection signal. As described above, the wheel motor 32 is configured by a member that absorbs most of the light components without reflecting, and the reflection seal 32a is configured by a member that reflects most of the light components, thereby emitting light. When the light emitted from the element 33a is applied to a region where the reflection seal 32a on the outer peripheral surface of the wheel motor 32 is not attached, the reflected light is received by the light receiving element as shown in FIG. No light is received at 33b. On the other hand, when the light emitted from the light emitting element 33a is applied to the reflective seal 32a attached to the outer peripheral surface of the wheel motor 32, as shown in FIG. Light is received at 33b. For example, an infrared LED (Light Emitting Diode) may be used as the light emitting element 33a, and a phototransistor may be used as the light receiving element 33b.

As shown in FIG. 2, the PC 10 in this example includes an interface unit 15, a display unit 11, an information input unit 14, and a control unit 16.
The interface unit 15 transmits and receives information and signals to and from the projector 20 via the cable 17.
The display unit 11 includes a display such as a liquid crystal and displays information.
The information input unit 14 includes a keyboard, a mouse, and the like, and is used for inputting information.
The control unit 16 includes an operation recognition unit 12 and an image generation unit 13. The operation recognition unit 12 recognizes the content of the operation with the electronic pen based on the operation position detected by the position detection unit 24 of the projector 20 and the function set for the electronic pen. The image generation unit 13 generates a video signal corresponding to the content of the operation recognized by the operation recognition unit 12 and outputs it to the projector 20 via the interface unit 15. For example, in a state in which a base image corresponding to a video signal output from the PC 10 is displayed on the screen 50 as a display image, the display image is displayed on the screen 50 by an electronic pen set to write information. When an operation for writing information is performed, it is set as a function to generate a video signal for displaying a new display image by combining the written information and a base image, or to operate as a mouse. When an operation designated by a predetermined icon in the display image is performed with the electronic pen, a video signal for displaying a new display image is generated according to the designated icon.

Below, the display method of the display image in the electronic blackboard system comprised as mentioned above is demonstrated.
First, an electronic pen used in the above-described electronic blackboard system will be described.
FIG. 4 is a diagram illustrating a configuration example of an electronic pen used in the electronic blackboard system illustrated in FIGS. 1 to 3.
As shown in FIG. 4, the electronic pen used in the electronic blackboard system shown in FIGS. 1 to 3 is configured by providing infrared light emitting portions 62 a and 62 b at the tips of the shaft portions 61 a and 61 b. The infrared light emitters 62a and 62b always emit infrared light having different wavelengths when pressed. In this embodiment, infrared light having a wavelength of 850 nm is emitted from the infrared light emitting unit 62a of the electronic pen 60a, and infrared light having a wavelength of 950 nm is emitted from the infrared light emitting unit 62b of the electronic pen 60b.

FIG. 5 is a flowchart for explaining a display image display method in the electronic blackboard system shown in FIGS.
In a state where a video signal is output from the PC 10 and a display image corresponding to the video signal is projected onto the projection area 51 via the projection lens 40 of the projector 20 and displayed on the screen 50, the camera unit 30 of the projector 20 performs the screen display. An imaging area 52 including 50 is imaged (step 1).
In this state, when the electronic pens 60a and 60b shown in FIG. 4 are operated while being pressed down on the screen 50, as described above, in the electronic pens 60a and 60b, the infrared light emitting units 62a and 62b are pressed down. Infrared light is emitted from the infrared light emitting sections 62a and 62b, and the infrared light is detected by the camera unit 30 (step 2).
In the camera unit 30, the optical filter wheel 37 is rotated with the rotation of the wheel motor 32. When the optical filter wheel 37 rotates, the two types of optical filters 37 a and 37 b constituting the optical filter wheel 37 alternately face the infrared capturing window 39.

FIG. 6 is a diagram showing the transmission characteristics of the optical filters 37a and 37b shown in FIG.
As shown in FIG. 6A, the optical filter 37a shown in FIG. 3 is a band-pass filter that transmits a wavelength having a width of about 100 nm centered at 850 nm. Further, as shown in FIG. 6B, the optical filter 37b shown in FIG. 3 is a band-pass filter that transmits a wavelength of about 100 nm centered at 950 nm.
On the other hand, in the electronic pens 60a and 60b, as described above, the electronic pen 60a emits infrared light having a wavelength of 850 nm from the infrared light emitting unit 62a, and the electronic pen 60b emits infrared light having a wavelength of 950 nm from the infrared light emitting unit 62b. Light is emitted.

Therefore, when the optical filter 37 a faces the infrared capturing window 39, the infrared light emitted from the infrared light emitting unit 62 a of the electronic pen 60 a is transmitted from the CMOS image sensor 31 via the optical filter 37 a and the lens 36. The infrared light that is captured and emitted from the infrared light emitting unit 62 b of the electronic pen 60 b is not captured by the CMOS image sensor 31. When the optical filter 37b faces the infrared capturing window 39, the infrared light emitted from the infrared light emitting unit 62b of the electronic pen 60b is transmitted by the CMOS image sensor 31 via the optical filter 37b and the lens 36. The infrared light that is captured and emitted from the infrared light emitting unit 62 a of the electronic pen 60 a is not captured by the CMOS image sensor 31.
Here, the optical filters 37a and 37b are alternately opposed to the infrared capturing window 39 by the rotation of the optical filter wheel 37. The rotation of the optical filter wheel 37 is detected by the rotation detection output from the photointerpreter 33. It is detected by the light distinction detection unit 23 based on the signal. As described above, the rotation detection signal output from the photointerpreter 33 is in accordance with the light reception intensity in the light receiving element 33b. A reflection seal 32a is affixed to one point of the boundary between the optical filters 37a and 37b on the outer peripheral surface of the wheel motor 32, and the light receiving element 33b is emitted from the light emitting element 33a and is outer periphery of the wheel motor 32. By receiving the light reflected by the surface, in the light discrimination detection unit 23, which of the optical filters 37 a and 37 b faces the infrared capturing window 39 based on the rotation detection signal output from the photointerpreter 33. You can recognize what you are doing. For example, when the optical filter wheel 37 rotates at 120 Hz, the rotation period of the optical filter wheel 37 is 8.3 ms. Therefore, the optical filter wheel 37 is emitted from the light emitting element 33a and reflected by the reflective seal 32a based on the rotation detection signal. The timing at which the reflected light is received by the light receiving element 33b is used as a trigger, and the infrared light captured by the CMOS image sensor 31 after 2.0 ms from the trigger, that is, after the optical filter wheel 37 is rotated by 1/4, The infrared light captured by the CMOS image sensor 31 after 6.2 ms from the trigger, that is, after the optical filter wheel 37 has been rotated by 3/4 rotation, passes through the optical filter 37b. It will be recognized as being transparent. The rotation frequency of the wheel motor 32 is controlled by the CPU 22. The CPU 22 calculates the rotation frequency of the optical filter wheel 37 based on the rotation period signal output from the photo interrupter 33, and the rotation frequency is always constant. Thus, feedback control is performed.
As described above, the light distinction detection unit 23 can distinguish and detect the light emitted from the electronic pens 60a and 60b for each of the electronic pens 60a and 60b according to the wavelength of the light.
Next, the position detection unit 24 detects the coordinates of the operation positions of the electronic pens 60a and 60b based on the position in the image of the light captured by the CMOS image sensor 31 (step 3). At this time, the coordinates of the operation position are detected for each of the electronic pens 60a and 60b by interlocking the rotation of the optical filter wheel 37 and the coordinate detection process using the infrared light capturing timing as described above in a time-sharing manner. be able to.

The coordinate information of the operation position detected for each of the electronic pens 60a and 60b in this way is transmitted from the projector 20 to the PC 10 through the cable 17 together with information indicating the timing at which the coordinates are detected.
Then, in the operation recognizing unit 12 of the PC 10, first, based on the information indicating the timing transmitted from the projector 20 together with the coordinate information of the operation position, the transmitted coordinate information is the operation of either of the electronic pens 60a and 60b. It is determined whether the position is indicated. As described above, the CMOS image is based on how much time has elapsed from the trigger based on the rotation detection signal output from the photointerpreter 33 when the coordinate of the operation position is detected. Since it is specified from which of the electronic pens 60a and 60b the infrared light captured by the sensor 31 is emitted, the transmitted coordinates are based on the timing at which the coordinates of the operation position are detected. It can be determined which information indicates the operation position of the electronic pens 60a and 60b.
When the operation recognition unit 12 determines which of the operation positions of the electronic pens 60a and 60b the coordinate information transmitted from the projector 20 indicates, the function set for the electronic pens 60a and 60b and Based on the coordinate information transmitted from the projector 20, the contents of the operation with the electronic pens 60a and 60b are recognized for each of the electronic pens 60a and 60b (step 4). For example, if the function set in the electronic pen 60a is to write information in black, it is recognized that the information is written in black at the operation position indicated by the coordinate information transmitted from the projector 20, If the function set in the electronic pen 60b is to write information in red, it is recognized that the information has been written in red at the operation position indicated by the coordinate information transmitted from the projector 20. . If the function set in the electronic pen 60b operates as a mouse, it is recognized that the icon displayed at the operation position indicated by the coordinate information transmitted from the projector 20 is specified. .

Next, the image generation unit 13 generates a video signal for displaying a display image corresponding to the content of the operation recognized in step 4. For example, when the function set in the electronic pen 60a is to write information in black, the information is written in black at the operation position on the display image that is the base image displayed on the screen 50. When a video signal for displaying a new display image obtained by combining information is generated, or when the function set in the electronic pen 60b operates as a mouse, it corresponds to the icon displayed at the operation position. A video signal for displaying a new display image is generated.
The video signal generated by the image generation unit 13 is transmitted from the PC 10 to the projector 20, and a display image corresponding to the video signal is projected via the projection unit 41 by the display control unit 25 and displayed on the screen 50. (Step 5). In addition, since the display of the display image according to the content of the operation with the electronic pens 60a and 60b affects the drawing response in this way, the optical filter for detecting the operation position with the electronic pens 60a and 60b. The rotation frequency of the wheel 37 needs to be sufficiently faster than the frame rate of the video signal. For example, when the frame rate of the video signal is 60 Hz, it is necessary to acquire coordinates according to the operation positions of both the electronic pens 60a and 60b with one rotation of the optical filter wheel 37, and thus a rotation frequency of 60 Hz is required. However, since the rotation of the optical filter wheel 37 and the video signal are asynchronous, the rotational frequency of the optical filter wheel 37 is about twice or more the frame rate of the video signal in order to provide a sufficient processing margin. It is preferable.

FIG. 7 is a diagram illustrating an example of a display image displayed on the screen 50.
In the state where the display image is displayed on the screen 50, for example, as shown in FIG. 7A, the display image is displayed on the screen 50 by the electronic pen 60a set as a function of writing information in black. When the operation of writing information on the display image is performed on the screen 50 by the electronic pen 60b set as the function of writing information in red, the operation of writing information on the screen is performed. And the base image are combined, and the black entry information 71a is displayed at the operation position by the electronic pen 60a, and the display image 70 in which the red entry information 71b is displayed at the operation position by the electronic pen 60b is displayed on the screen 50. Will be displayed.
Further, in a state where the display image is displayed on the screen 50, for example, as shown in FIG. 7B, the electronic pen 60a set as a function to write information in black is displayed on the screen 50. When an operation of writing information to the display image is performed, the written information and the base image are combined, and a display image 70 in which black entry information 71a is displayed at the operation position by the electronic pen 60a is displayed on the screen 50. In addition, an operation for designating a predetermined icon 72f among the plurality of icons 72a to 72i displayed on the display image 70 is performed by the electronic pen 60b set to function as a mouse. A new display screen is displayed on the screen 50 in accordance with the designated icon 72f. It made.

  Thus, in this embodiment, the operation position on the screen 50 by the plurality of electronic pens that emit infrared light having different wavelengths is used by using two types of optical filters 37a and 37b that transmit infrared light having different wavelengths. By making detection possible for each electronic pen, it is possible to display a display image by identifying operations with a plurality of electronic pens with a simple configuration.

As described above, in order to correctly detect the operation position in the display image of the electronic pen based on the position of the infrared light detected in the imaging area 52, the display image and the camera projected by the projector 20 The correlation with the image captured by the unit 30 needs to be adjusted.
FIG. 8 is a diagram illustrating an example of a test pattern used for adjusting the correlation between the display image projected by the projector 20 and the image captured by the camera unit 30.
For example, as shown in FIG. 8, a calibration test pattern image 80 in which nine calibration points 81a to 81i are arranged in a matrix is projected on the screen 50 from the projector 20, and the calibration points 81a to 81i are projected. By touching all with the electronic pen, the correlation between the coordinates of the display screen projected from the projector 20 and the coordinates of the screen imaged by the projector 20 can be established.

In the above-described embodiment, the example in which the two electronic pens 60a and 60b that emit infrared light having different wavelengths are used has been described. However, the wavelengths of infrared light emitted from a plurality of electronic pens are finely defined. If it can be set, the number of electronic pens can be increased. In this case, the optical filter wheel 37 has as many optical filters as the number of electronic pens, and the plurality of optical filters are set to selectively face the infrared capturing window 39 by the rotation of the optical filter wheel 37. It will be.
Further, the light emitted from the electronic pens 60a and 60b may be other than infrared light as long as the wavelengths are different from each other. However, in the case of visible light, it is difficult to see the display image.
Moreover, although the electronic blackboard system is comprised from the projector 20 and PC10, all the components may be integrated in a direct-view monitor display, and an electronic blackboard system may be comprised only by a direct-view monitor display.

(Appendix 1)
A plurality of electronic pens that emit light of different wavelengths;
A light detection unit that images an imaging area and detects light emitted from the electronic pen by distinguishing the plurality of electronic pens according to the wavelength of the light; and
A position detection unit that detects an operation position of the electronic pen for each of the plurality of electronic pens based on a position in the imaging area of the light detected by the light detection unit;
A recognition unit for recognizing the content of the operation by the electronic pen for each of the plurality of electronic pens based on the operation position detected by the position detection unit and the function set for each of the plurality of electronic pens;
An image generation unit that generates and outputs a video signal according to the content of the operation recognized by the recognition unit;
An electronic blackboard system, comprising: a display unit configured to display a display image corresponding to the video signal output from the image generation unit.
(Appendix 2)
In the electronic blackboard system described in Appendix 1,
The light detection unit is
Corresponding to each of the plurality of electronic pens, among the plurality of electronic pens, a plurality of lights that transmit light having a wavelength emitted from the corresponding electronic pen and that do not transmit light having a wavelength emitted from other electronic pens A transmission part;
An electronic blackboard system comprising: a light receiving unit that detects light emitted from the electronic pen by receiving light transmitted through the light transmission unit.
(Appendix 3)
In the electronic blackboard system described in Appendix 2,
The light detection unit is
A window for capturing light emitted from the electronic pen;
The plurality of light transmission parts are arranged side by side in the rotation direction, and the filter wheel is arranged so that the plurality of light transmission parts selectively oppose the window part with rotation,
An identification mark that moves with the rotation of the filter wheel;
A light emitting element that emits light of a predetermined brightness so as to intersect the trajectory of the identification mark moving;
A light receiving element that receives reflected light from which light emitted from the light emitting element is reflected;
An electronic blackboard system comprising: a distinguishing unit that distinguishes each of the plurality of electronic pens based on a change in received light intensity corresponding to the brightness of light received by the light receiving element. .
(Appendix 4)
In the electronic blackboard system described in Appendix 3,
An electronic blackboard system in which a rotation frequency of the filter wheel is constant.
(Appendix 5)
In the electronic blackboard system according to claim 3 or 4,
The electronic blackboard system, wherein a rotation frequency of the filter wheel is twice or more a frame rate of the video signal.
(Appendix 6)
A display device equipped with an electronic pen,
The electronic pen emits light of different wavelengths,
The display device
A light detection unit that images an imaging area and detects light emitted from the electronic pen by distinguishing the plurality of electronic pens according to the wavelength of the light; and
A position detection unit that detects an operation position of the electronic pen for each of the plurality of electronic pens based on a position in the imaging area of the light detected by the light detection unit;
Display according to the content of the operation with the electronic pen recognized for each of the plurality of electronic pens based on the operation position detected by the position detection unit and the function set for each of the plurality of electronic pens And a display unit that displays an image.
(Appendix 7)
A display image display method in an electronic blackboard system in which a plurality of electronic pens that emit light of different wavelengths is operated,
A light detection process for picking up an imaging area and detecting the light emitted from the electronic pen by distinguishing the plurality of electronic pens according to the wavelength of the light; and
A position detection process for detecting an operation position of the electronic pen for each of the plurality of electronic pens based on a position of the light detected in the light detection process in the imaging area;
A recognition process for recognizing the operation content of the electronic pen for each of the plurality of electronic pens based on the operation position detected in the position detection process and the function set for each of the plurality of electronic pens;
And a display process for generating a video signal corresponding to the content of the operation recognized in the recognition process and displaying a display image corresponding to the video signal.

10 PC
DESCRIPTION OF SYMBOLS 11 Display part 12 Operation recognition part 13 Image generation part 14 Information input part 15, 21 Interface part 16 Control part 17 Cable 20 Projector 22 CPU
DESCRIPTION OF SYMBOLS 23 Light distinction detection part 24 Position detection part 25 Display control part 30 Camera unit 31 CMOS image sensor 32 Motor for wheel 32a Reflective seal 33 Photointerpreter 33a Light emitting element 33b Light receiving element 35 Substrate 36 Lens 36 Optical filter wheel 37a, 37b Filter 38 Case 39 Infrared capturing window 40 Projection lens 41 Projection unit 50 Screen 51 Projection area 52 Imaging area 60a, 60b Electronic pen 61a, 61b Shaft unit 62a, 62b Infrared light emitting unit 70 Display image 71a, 71b Entry information 72a-72i Icon 80 Calibration Test pattern images 81a to 81i Calibration points

Claims (7)

A plurality of electronic pens that emit light of different wavelengths;
A light detection unit that images an imaging area and detects light emitted from the electronic pen by distinguishing the plurality of electronic pens according to the wavelength of the light; and
A position detection unit that detects an operation position of the electronic pen for each of the plurality of electronic pens based on a position in the imaging area of the light detected by the light detection unit;
A recognition unit for recognizing the content of the operation by the electronic pen for each of the plurality of electronic pens based on the operation position detected by the position detection unit and the function set for each of the plurality of electronic pens;
An image generation unit that generates and outputs a video signal according to the content of the operation recognized by the recognition unit;
An electronic blackboard system, comprising: a display unit configured to display a display image corresponding to the video signal output from the image generation unit. The electronic blackboard system according to claim 1,
The light detection unit is
Corresponding to each of the plurality of electronic pens, among the plurality of electronic pens, a plurality of lights that transmit light having a wavelength emitted from the corresponding electronic pen and that do not transmit light having a wavelength emitted from other electronic pens A transmission part;
An electronic blackboard system comprising: a light receiving unit that detects light emitted from the electronic pen by receiving light transmitted through the light transmission unit. The electronic blackboard system according to claim 2,
The light detection unit is
A window for capturing light emitted from the electronic pen;
The plurality of light transmission parts are arranged side by side in the rotation direction, and the filter wheel is arranged so that the plurality of light transmission parts selectively oppose the window part with rotation,
An identification mark that moves with the rotation of the filter wheel;
A light emitting element that emits light of a predetermined brightness so as to intersect the trajectory of the identification mark moving;
A light receiving element that receives reflected light from which light emitted from the light emitting element is reflected;
An electronic blackboard system comprising: a distinguishing unit that distinguishes each of the plurality of electronic pens based on a change in received light intensity corresponding to the brightness of light received by the light receiving element. . The electronic blackboard system according to claim 3,
An electronic blackboard system in which a rotation frequency of the filter wheel is constant. In the electronic blackboard system according to claim 3 or 4,
The electronic blackboard system, wherein a rotation frequency of the filter wheel is twice or more a frame rate of the video signal. A display device equipped with an electronic pen,
The electronic pen emits light of different wavelengths,
The display device
A light detection unit that images an imaging area and detects light emitted from the electronic pen by distinguishing the plurality of electronic pens according to the wavelength of the light; and
A position detection unit that detects an operation position of the electronic pen for each of the plurality of electronic pens based on a position in the imaging area of the light detected by the light detection unit;
Display according to the content of the operation with the electronic pen recognized for each of the plurality of electronic pens based on the operation position detected by the position detection unit and the function set for each of the plurality of electronic pens And a display unit that displays an image. A display image display method in an electronic blackboard system in which a plurality of electronic pens that emit light of different wavelengths is operated,
A light detection process for picking up an imaging area and detecting the light emitted from the electronic pen by distinguishing the plurality of electronic pens according to the wavelength of the light; and
A position detection process for detecting an operation position of the electronic pen for each of the plurality of electronic pens based on a position of the light detected in the light detection process in the imaging area;
A recognition process for recognizing the operation content of the electronic pen for each of the plurality of electronic pens based on the operation position detected in the position detection process and the function set for each of the plurality of electronic pens;
And a display process for generating a video signal corresponding to the content of the operation recognized in the recognition process and displaying a display image corresponding to the video signal.

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