JPH0895157A - Display device - Google Patents

Abstract

PURPOSE: To provide a display device capable of being inputted by plural people simultaneously on a large screen display by using pointers and capable of easily confirming visible light outputted by respective pointers. CONSTITUTION: A projection part 104 projects light on a screen 103 so as to display a picture. Plural pointers 101 and 102 project the light for input having different color to the front surface of the screen 103. A camera 105 photographs the image of the screen 103 from the back surface of the screen 103 and transmits the photographed image to an input detection part 107. Which pointer, out of plural pointers 101 and 102, projects the light is discriminated by the input detection part 107 based on the image by utilizing that the color of the light projected on the screen 103 by plural pointers 101 and 102 is different from each other.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a display device having a pointer for inputting an operation or the like to an image displayed on a screen by light, and more particularly to a display device which can be operated simultaneously by a plurality of pointers.

[0002]

2. Description of the Related Art In a computer system having a display device, as a means for accepting an instruction to operate an image displayed on the display device, a display screen (screen) of the display device is brought into direct contact with a hand or other object. There are some that give instructions for operation. A touch panel and a stylus pen are examples of such instruction means according to the related art. With these methods,
The person who gives the instruction needs to operate while touching the screen of the display with his / her finger or the like, and when the screen is often viewed from a place away from the screen like a large display device, this method is used to It is inconvenient to try to indicate the position.

Therefore, in a large display device,
As a device for instructing a position on a screen, which is a display screen, from a place distant from the screen, Japanese Patent Laid-Open No. 5-1
There is one described in Japanese Patent No. 50753, "Light Beam Projection Image Display Device". This display device is a rear projection type large display device in which a projector for displaying an image on the screen is on the back surface of the screen. In this device, a device incorporating a light emitting element that outputs infrared laser light is used as a pointer for pointing a position on the screen. The position where the infrared laser light output from the pointer hits the screen is detected by a sensor provided on the back surface of the screen. Then, the input position of the user is identified from the position. Since infrared rays are invisible, the position can be confirmed by displaying an image at the identified position.

However, this device is premised on that only one user gives an instruction on the screen, and consideration is given to the case where a plurality of persons simultaneously hold the pointer and indicate a plurality of positions on the screen. I haven't. In this case, the position specified by one user cannot be distinguished from the position specified by another user. Therefore, there is a problem that the position is erroneously identified and an instruction different from the user's intention is given. Therefore, multiple people cannot use the pointer at the same time.

A pointer for solving this problem is described in Japanese Patent Application Laid-Open No. 5-224636 "Method and apparatus for interacting with computer output projected image". This device uses multiple pointers that emit infrared or visible light. The plurality of pointers are distinguished from each other by modulating the infrared rays or visible light with different frequencies (frequency of 35 kHz or less) to form rectangular waves of different frequencies. When detecting infrared rays or visible light, it is possible to distinguish between pointers by using a bandpass filter according to the modulation frequency.

[0006]

In the above prior art, in order to be able to distinguish the output light from a plurality of pointers, it was necessary for each pointer to have a modulator for modulating the output light.

It is a first object of the present invention to provide a display device which does not have a modulation device and allows a plurality of users to simultaneously specify positions with pointers.

By the way, in the case of a large front projection type display device, both the light from the projector and the light from the pointer are reflected on the front surface of the screen and enter a sensor for detecting the projection position of the pointer. For this reason, when the light from the pointer and the light from the projector have the same property as the light, such as when the light has the same color or the same intensity, the position of the pointer cannot be recognized. Even in the case of a rear projection type large display device, the same problem as described above may occur when a large amount of light from the projector is reflected on the back surface of the screen due to poor transparency of the screen.

A second object of the invention is that the light emitted by the projector and the light emitted by the pointer can be in the same state, and both lights can enter the device for measuring the position of the pointer. It is an object of the present invention to provide a display device which can distinguish both lights without having a device.

[0010]

In order to achieve the first object, a screen on which an image is displayed, display means for displaying the image by projecting light on the screen, and on the screen And a position designating unit for designating the position, the position designating unit designates the position different from each other in at least one of color of light, intensity of light, and polarization state of light. A plurality of pointers for projecting light to the screen from the front surface of the screen, a camera for receiving the plurality of lights projected on the screen by the plurality of pointers, and a pointer for receiving the light. The position identification means for identifying the position specified by, and the received light are at least the color of the light, the intensity of the light, and the polarization state of the light. Based on the fact that one is different from the other, the pointer identifying means for identifying which of the plurality of pointers is the light projected by each of the identified positions is provided. .

In order to achieve the above second object,
The screen has a screen on which an image is displayed, display means for displaying light by projecting light in one polarization state onto the screen, and position specifying means for specifying the position on the screen. The means includes at least light in a polarization state different from the light projected by the display means on the screen, and is different from each other in at least one of the color and the intensity of the included light.
A plurality of pointers for projecting the light for designating the position from the front surface of the screen, a polarization selecting means for selecting and transmitting light in a polarization state different from the light projected by the display means, and the polarization selecting A camera for receiving the polarized light selected by the means, position identifying means for identifying the position designated by the pointer by the received light, and the received light among the light projected on the screen by the plurality of pointers. For each of the identified positions, the light determines which of the plurality of pointers the light is projected based on the fact that at least one of the light color and the light intensity is different from each other. And a pointer identifying means for identifying.

[0012]

The plurality of pointers project light having different characteristics for each pointer. The camera receives the light reflected on the screen of a large display. The position identification means performs image processing on it to detect a plurality of input positions. Further, the pointer identifying means distinguishes a plurality of input positions on the screen for each pointer based on the color, intensity, or polarization state of light of each pointer. With the above operation, even if a plurality of users simultaneously input with a plurality of pointers, the input position can be identified for each pointer.

In order to distinguish the colors of light, for example, each pointer may have a light emitting diode of a different light emission color. To distinguish the intensity of light, for example,
The light emitting diode may be made to emit light with different intensity for each pointer. Further, in order to distinguish the polarization state of light, for example, a different polarizing plate is provided for each pointer on the front surface of the light emitting diode so that each pointer emits different polarized light, and the light is output through this polarizing plate. You can do it. In this way, since the plurality of pointers are distinguished from each other by the color of light, the intensity, or the polarization state of light, the plurality of pointers can be identified by a pointer having a simple structure without the need for a modulator.

Further, the light emitted from the display means is assumed to be light in one polarization state, the pointer outputs light having different polarization states, and the display means outputs the polarization selection means to the camera. Avoid getting light. Thereby, the light from the display means and the light from the pointer can be distinguished and the position of the pointer can be correctly recognized without providing the modulator.

[0015]

EXAMPLE A first example of the display device according to the present invention will be described with reference to FIG. FIG. 1 is a block diagram of a display device. The present device is a rear projection display device in which a projection unit for displaying an image on the screen is provided on the back surface of a transmissive screen, and a user views the image from the front surface of the screen and gives an instruction with a pointer. The case where the number of pointers is two will be described below, but the present invention is not limited to this. This display device has pointers 101, 1
02 and a computer system that performs processing in accordance with the input. The computer system includes a control unit 106 that controls the entire computer, a screen 103 that is a display surface, and projection points 1011 and 1021 provided on the back of the screen by pointers 101 and 102 reflected on the back of the screen 103.
The camera 105 that captures the entire back surface of the screen 103 including the input, the input detection unit 107 that detects the input position of the user from the image captured by the camera 105, and the information that should be displayed from the control unit 106 into an analog RGB signal. The display unit 108 to be converted, and the analog RGB from the display unit 108
It has a projection unit 104 that projects an image on the screen 103 based on a signal, and a bus 109 that connects the control unit 106, the input detection unit 107, and the display unit 108.

The input detection unit 107 receives the plurality of lights projected on the screen 103 by the pointers 101 and 102, identifies the projected position, and the colors of the lights are different from each other. Based on the above, it has a function of discriminating which of the plurality of pointers 101 and 102 is the light projected by the pointer.

The hardware configuration of the computer system is shown in FIG.
3 shows. The computer system includes a CPU 131, a main memory 132, a display unit 108, a projection unit 104, a hard disk 134, an input / output control unit 135, and a camera 105.
Have and. The control unit 106 is realized by the CPU 131 and the main memory 132, and the input detection unit 107 is a CP.
It is realized by the U 131, the main memory 132, and the input / output control unit 135.

In the main memory 132, the control unit 106, the input detection unit 107, and the display unit 108 executed by the CPU 131.
The processing program of is stored at the time of execution.

The hard disk 134 has a pointer 10
The information of the position designated by 1, 102 and identified by the input detection unit 107, the identification information of the pointer (pointer type), and the like are stored. Further, the control unit 106, the input detection unit 107, and the display unit 108 executed by the CPU 131.
Are stored and are transferred to the main memory when these processing programs are executed.

The display unit 108 receives a drawing command for generating an image to be displayed on the screen 103 from the CPU 131, generates an RGB signal based on this drawing command, and outputs it to the projection unit 104. FIG. 16 shows the internal structure of the display unit 106. The display unit 106 includes a drawing unit 1061, a frame memory 1062, and an RGB signal generator 1063. The drawing unit 1061 obtains data corresponding to the graphic according to the drawing command received from the control unit 106, and stores the data in the frame memory 1062. The RGB signal generator 1063 converts the bitmap information in the frame memory 1062 into an RGB signal. For example, when displaying a straight line, the control unit 106 outputs to the display unit 106 an instruction to draw the straight line and the coordinates of the start point and the end point. The drawing unit 1061 refers to the coordinates from the control unit 106 and generates a straight line on the frame memory 1062. RG
The B signal generator 1063 scans the frame memory 1062 at regular intervals to generate RGB signals.

The input / output control unit 135 receives an instruction from the CPU 131, and at the timing to be described later, the camera 105.
Analog-to-digital conversion is performed on the analog RGB signal from and the obtained digital data is sent to the main memory 132.
The main memory 132 stores this digital data.

Each component of the display device will be described with reference to FIG. The pointers 101 and 102 each have a light emitting element (light emitting diode or laser diode) that outputs visible light, and each pointer 101 and 102 outputs light of a different wavelength. The structure of the pointers 101 and 102 is shown in FIG.
4 shows. The pointers 101 and 102 each include a light emitting diode 141, a switch 142 for turning on / off the light emitting diode 141, and a battery 143.

The screen 103 is of the transmissive type as described above, and is composed of, for example, a Fresnel lens for refracting the light projected by the projection unit 104 from the rear surface of the screen in the front direction of the screen and a diffusing surface.

The projection unit 104 uses a CRT projection type in which a CRT (cathode ray tube) is used as a light source, and three visible light lasers which respectively output RGB as a light source, and directly outputs a laser beam output from them. Either a laser projection type in which the intensity is modulated by a signal or a liquid crystal projection type using a color filter using liquid crystal may be used.

The camera 105 arranged behind the screen 103 is arranged so that the entire screen 103 can be photographed. If screen 103 and camera 1
When the distance from 05 is not secured, the optical path is lengthened by using a reflecting mirror, or a wide-angle lens is used as a lens so that the camera 105 can photograph the entire screen 103. The camera 105 outputs the captured image of the screen 103 as a video signal.

The camera 105 and the projection unit 104 may be operated in synchronization with each other, or may be operated without synchronization. When operating in synchronization,
It is desirable to take an image with the camera 105 during the vertical blanking period of the projection unit 104. This is because if the light from the projection unit 104 enters the camera 105, the light from the projection 104 and the light from the pointers 101 and 102 can be easily distinguished.

The principle for identifying the pointer in this embodiment will be described. The user operates the pointers 101 and 102 that project light of different wavelengths to project the light on the screen 103. On the back side (back side) of the screen 103 as shown in FIG.
Projection points 1011 and 1021 of the colors corresponding to the pointers 101 and 102 appear at the positions designated by 2. If this is seen from the back of the screen 103, each pointer 101,
Depending on the positions of the projection points 1011 and 1021 for each 102,
The input position can be detected, and the projection points 1011 and 10
It is possible to distinguish the pointers 101 and 102 by the colors of 21.

The colors of the projection points 1011 and 1021 are
It may match the color of the displayed image. However, this embodiment does not cause a problem for the following reason. In the case of a rear projection type display device like this embodiment,
The image is projected onto the screen 103 from the back surface, and the light from the pointers 101 and 102 is projected from the front surface of the screen 103. Then, the screen 103 of this embodiment
Has a property of transmitting incident light, the light from the pointers 101 and 102 mainly enters the camera 105, the light of the image reflected by the screen 103 and entering the camera 105 is small, and the projection point 1011 , 1021 and the color of the image are not confused with each other.

Next, the input detection section 10 for performing this identification processing.
7 will be described. The input detection unit 107 includes the camera 10
The user's input is identified based on the video imaged by the camera 5. The image captured by the camera 105 is a camera image 110 obtained by capturing the entire screen 103 as illustrated. The camera 105 uses the captured camera image 110 as an analog RG.
It is converted into a B signal and sent to the input detection unit 107. The input detection unit 107 uses analog RGB signals sent from the camera 105.
The signal of 1 frame is sampled at a predetermined timing.

There are the following two methods for sampling timing, and either method may be used.

1. The input detection unit 107, which performs sampling at regular intervals, determines a sampling cycle at a time larger than the time required for the input detection unit 107 to perform predetermined processing such as identification of the input position and pointer type for image data of one frame. Is the way. For example, the input detection unit 107 determines to perform sampling every 20 milliseconds.

2. When the input detection unit 107, which does not perform sampling at regular intervals, completes predetermined processing such as identification of the input position and pointer type for the image data of one frame, the input detection unit 107 immediately detects from the camera 104. The RGB signals of are sampled.

When one frame of the image from the camera 105 is sampled, next, the projection point 10 is included in the image.
It is checked whether or not there is 11, 1021, and it is judged whether or not there is an input from the user.

By the way, the input detector 107 needs to detect the input position and the event type. Here, the input position and the event type are as follows, respectively.

A mouse, which is a typical input device, will be described as an example. The input position means the position when the mouse is moved.
This is the position of the cursor on the display screen that follows the movement. The event type represents the type of user's instruction, and is, for example, a specific display request / a specific display deletion request. In the case of a mouse, the event type is identified when the mouse button is pressed (button down), when the button is released (button up), or the like. In this embodiment, the pointer 1 is used to specify the input position and input the event type.
01 and 102, the following input method is adopted.

The input position is set by the user to the pointers 101, 1
The position where the light from 02 is projected on the screen 103.

Regarding the event type, pointer 101,
It is assumed that by turning on the switch 142 of 102, when the user starts projection to a certain position on the screen 103, an input corresponding to button down of the mouse is made at that position. In addition, after the switches of the pointers 101 and 102 are turned on (in the projected state), the projection position of the pointers 101 and 102 is moved to a position desired by the user, and then the switch 142 is turned off at that position. Thus, it is determined that the input corresponding to the button up of the mouse has been performed. When the button down is defined as described above, the user may perform the button down at the wrong position because the projection position is unknown until the pointers 101 and 102 are projected for the first time. However, in the present embodiment, since it is assumed that the menu at the projection position where the button is raised is selected, the selection of the menu will not be mistaken.

If the button-down is the same as the double-click of the mouse when the ON operation is performed twice in succession, it is interpreted as the button-down even if the ON operation is performed once at the wrong position. The menu selection is invalidated.
As a result, only the menu at the projection position where the button down is performed is selected.

Further, the input detection unit 107 also outputs the pointer type (unique number for identifying each pointer). In order to provide an environment in which a plurality of people can perform input simultaneously, when a plurality of users each have a pointer and perform input simultaneously, the input detection unit 10
7 is because it is necessary to distinguish a plurality of input devices (pointers) that are simultaneously input.

In order to detect the above-mentioned input position, event type, and pointer type, the input detection unit 107 first samples the camera image, then simultaneously detects the input position and pointer type, and then detects the event type. I do.

The operation of the input detector 107 will be described with reference to the processing flow of FIG.

Step 201 The camera 105 converts the image 110 showing the entire screen into RGB signals and sends them to the input detection unit 107. The input detection unit 107 samples this signal. As a sampling order, the scanning lines forming one frame are sequentially sampled from top to bottom. One scan line is sequentially sampled from left to right. The number of pixels on one scanning line at this time is M. By sampling, 8-bit data is created for each RGB component of each pixel in the camera image 110 of one frame obtained by photographing the screen 103. This data is
It is stored in the main memory 132.

Step 202 By the processing up to the following Step 211, the input detection unit 1
07 detects the input information, so that the input position and the pointer type are checked at the same time. After that, the event type is determined. In steps 202 to 207 out of steps 202 to 211, it is checked for each pointer type whether or not there is a pointer in the sampled image. Hereinafter, a method of searching for a pointer that outputs red light (hereinafter, referred to as a red pointer) will be described as a pointer type.
In order to check the red pointer, the input detection unit 107
Finds the reddest point in the sampled image.

In step 202, in order to detect the input position, the variable (maximum variable) for storing the information on the color intensity of each pointer is initialized to 0. For example, in the case of red, the maximum red variable is set to 0.

Step 203 Regarding the sampled data for each pixel from the first pixel to the last pixel in one frame, step 2
Steps 204 to 2 which are lower processing steps of 03
Execute 07.

Step 204 The input detection unit 107 inspects the RGB value of each pixel in the same order as the sampling order, and determines whether the other component (GB) is 0 and the R component is larger than the red maximum variable. Determine whether If a pixel is found, go to step 205,
If not, step 204 is performed for the next pixel.

Step 205 From the pixel number (one serial number added in the sampling order for the pixels in one frame) to the camera coordinates (P _x ,
_Py ) is acquired. The calculation at this time can be calculated by the following formula when the pixel is the Nth pixel.

P _x = mod (N, M), P _y = integer (N /
M) integer is a function for converting to integers These coordinates are coordinates in a coordinate system defined on the image pickup surface of the camera 101, and this coordinate system is called a camera coordinate system.
On the other hand, the position of the displayed image is managed by the coordinate system (screen coordinate system) of the pixels projected by the projection unit 104. Therefore, it is necessary to convert the position obtained in the camera coordinate system into the position in the screen coordinate system. The correspondence between the camera coordinate system and the screen coordinate system is determined by the projection unit 104 and the screen 103.
And the position of the camera 105. For this reason,
The input detection unit 107 has a camera coordinate system (Px,
Py) and screen coordinate system (X, Y) coordinate conversion formula X = f
X (Px, Py) and Y = fY (Px, Py) are stored. Then, with this conversion formula, the obtained position on the camera image is set to the position on the screen coordinate system in step 210 described later.
Convert with.

In step 206, the red maximum variable is set to the value of R of the pixel in step 205.

Step 207: For the other pointer colors, also refer to Step 204-20.
The same process as 6 is performed.

By performing the above steps 204 to 207 for all pixels, the camera coordinates of the pixel having the maximum value of the color can be obtained for each color of the pointer.

Step 208 It is checked whether or not the input position is detected for each color. If the value of the red maximum variable is 0, the process proceeds to step 209. If the value of the red maximum variable is not 0, it is determined that there is an input at some point, the process proceeds to steps 210-212, and the input information is output.

Step 209 The input detection unit 107 determines that there is no input from red.

Step 210 The position on the camera coordinates is converted into the screen coordinate system managed inside the computer. For this reason, the input detection unit 107 preliminarily sets the camera image system (P _x , P _y ) and the screen coordinate system (X,
Y) conversion formula, X = X (P _x , P _y ), Y = Y (P _x ,
P _y ) is stored and the pointer position (P _x , P _y ) on the camera image is converted into the screen coordinate system.

In this way, the input position can be detected based on the presence / absence of the RGB pattern determined for each emission color of each pointer type, and the input position can be detected for each pointer type.

Step 211 Check the event type. In the present embodiment, the event type is detected based on the change in the light emitting state of the pointers 101 and 102, that is, whether the pointer has started to emit light and whether the pointer has finished emitting light. Therefore, the input detection unit 107 stores the previous status information. Specifically, main memory 1
It is stored in 32. Here, the status information refers to three positions of the projection position by the pointer, the color of the pointer, and the projection state. The projection state refers to a state of whether or not the pointers 101 and 102 are projecting. Further, the previous time and the current time mean the time of the previous time of the sampling and the time of the current time of the sampling. Therefore, in terms of the number of frames, when the processing for one frame is shorter than the cycle of sending one frame from the camera, the previous time means one frame before. When the processing for one frame is longer than the period for sending one frame from the camera, the previous time means two frames or more before.

The input detection unit 107 uses the pointer 10 described above.
Each time the process of detecting that the input is performed by the input terminal 1 or 102 is performed, the input detection unit 107 generates the following input information based on the information compared with the status information immediately before. This information is sent to the control unit 106. Here, the input information refers to three of the pointer projection position, the pointer color, and the input state for all pointers. The input state refers to a state of button down, button up, or moving.

When it is detected that an input is made by the pointer this time, and when it is also detected the last time, the input information indicating that the previously detected pointer type is moving to the coordinate position detected this time is input to the control unit. 1
Send to 06.

When it is detected that an input is made by the pointer this time, but not the previous time, the input information that the pointer type detected previously is button-down at the coordinate position detected this time is controlled. To the unit 106.

When the previous input is detected without detecting the input by the pointer this time, regarding the input state, the input information indicating that the pointer type detected this time is button-up at the previous coordinate position is input to the control unit 1.
Send to 06.

When the input by the pointer is not detected this time and it is not detected in the previous time, it is determined that there is no input from the pointer type to be processed, and nothing is transmitted to the control unit 106.

Step 212: Input information generated in Step 211, for example, detected pointer type (red), event type (button down),
The event occurrence position (x, y) is sent to the control unit 106.

Step 213 The same processing as Steps 208 to 212 is performed for each luminescent color of each pointer.

In the above description, the color having only one of the three primary colors such as red has been described.
The present invention is not limited to this, and can similarly detect a color composed of two or three colors of RGB.

Further, color detection was performed only for one pixel. As a result of trial production, this method was confirmed to be sufficiently effective. In addition, normally, the pixel having the maximum intensity is
Since it is possible that a plurality of groups are gathered, the group may be detected. This method is considered to be more reliable than detecting only one pixel.

Since the screen is a large screen, the size of the projection point of the pointer may be too small, and the resolution may be insufficient when shooting with a camera. It was confirmed that it could be detected sufficiently with a pointer and a camera.

The control unit 106, which has received the above-mentioned input information from the input detection unit 107, executes the processing according to the input information for each pointer. For example, when multiple menus are displayed on the screen and the button up is performed on any one menu on the screen, it is interpreted that the menu at the position where the button up is performed is selected. ,
Perform the process to open the menu. As a result of this execution,
Data for generating an image for displaying the opened menu is sent to the display unit 108. At this time, the pointer 101,
The designated position of 102 may be unstable due to camera shake or the like. Therefore, to specify the position of the menu,
A permissible area is provided for each menu, and when the pointers 101 and 102 are within the permissible area of one menu, the menu is selected.

The display unit 108 generates analog RGB signals according to this data. The generated RGB signal is sent to the projection unit 104.

The projection unit 104 projects light on the screen 103 according to the RGB signals.

Here, a method of determining a conversion formula for converting the position coordinates in the camera coordinate system to the position coordinates in the screen coordinate system will be described. The correspondence between the two coordinate systems corresponds to the projection unit 10.
4. The positional relationship between the screen 103 and the camera 105 depends on the positional relationship between the two coordinate systems, but the positional relationship between the two coordinate systems is not always fixed. Therefore, it is necessary to determine the conversion formula at the start of use of the display device.

In this embodiment, the screen 10 is previously set.
By projecting two marks on the screen 103 by the projection unit 104 on 3 and pointing the marks with one pointer, a conversion formula for converting the camera coordinate system and the screen coordinate system is determined. This mark indicates the screen 103
It is displayed at two points on the diagonal line of. And these two points,
The conversion formula is obtained by associating the coordinates in the camera coordinate system with the coordinates in the screen coordinate system.

The screen coordinate system has xy coordinates (0, 0) to (1280, 1024). First, the control unit 106 displays the predetermined mark at the position (100, 100) on the screen coordinate system. The user looks at the mark on the screen 103, projects light with the pointer on the mark, and stops light emission on the mark. The input detection unit 107 uses the default conversion formula, X = P, at the start of use.
Since x and Y = Py are stored, the coordinates detected in the camera coordinate system by this formula are output to the control unit 106 as they are. The control unit 106 sets the detected coordinates to P1 (Px1, Px1
It is stored as y1). Next, the control unit 106 erases the previous mark and displays the same mark as the previous mark at the point (1000, 900). As in the previous time, the user sees the mark on the screen 103, projects light with the pointer on the mark, and stops light emission on the mark. The input detection unit detects a pointing point on the camera coordinates and sets the coordinates to the control unit 1.
It outputs to 06. The control unit 106 sets the detected coordinates to P2 (P
x2, Py2).

Next, the control unit 106 uses the above two detected coordinates to create a conversion formula for converting the coordinates of the camera coordinate system into the coordinates of the screen coordinate system by linear conversion. That is,
The coordinate values (Px1, Py1) of P1 and the coordinate values (Px2, Py2) of P2 are expressed as Px1, Py1, P in the following equation.
The conversion formula is obtained by substituting for x2 and Py2.

X = ((1000-100) / (Px2-
Px1)) * (Px-Px1) +100 Y = ((900-100) / (Py2-Py1)) *
(Py-Py1) +100 This formula is a conversion formula for converting the coordinates (Px, Py) in the camera coordinate system into the coordinates (X, Y) in the screen coordinate system.

As described above, according to this embodiment, a plurality of users can independently input by projecting a large screen with pointers having different luminescent colors. Further, since the pointer projects visible light on the screen, the color of visible light can be easily confirmed even when the projection unit of the display device is not operating.

In the above-mentioned embodiment, as the kind of pointer, the color of RGB (frequency of light) is changed to distinguish a plurality of pointers. The above is a rear projection type, so there will be no misidentification even if the color of the light from the projection unit and the color of the light projected by the pointer are the same, but in the case of the front projection type,
False positives can occur. Therefore, in the case of the front projection type, when the color of light from the projection unit is limited, it is desirable to use a color different from the color of light from the projection unit for the pointer.

In addition to changing the color of the pointers, a method of distinguishing the pointers by changing the light intensity of each pointer can be considered. For example, when a plurality of red pointers having different light intensities are used, the input detection unit measures the intensity range of the R component value for each pointer in advance and stores it. The input detection unit checks which pointer strength range the detected R component value is in, determines the pointer type, and identifies the input position for each pointer.

Next, a second embodiment using this method will be described. In this embodiment, a plurality of pointers are distinguished by the intensity of light. All colors are the same, and the case of red will be described as an example.

The structure of the display device according to the present embodiment is shown in FIG. The present embodiment is a rear projection type display device as in the first embodiment. In this embodiment, two red pointers 60
1, 602 irradiate lights of different brightness. Pointer 6
01 emits light stronger than the pointer 602. Camera 1
05 is two red points 6011 ′, 60 of different strength.
The camera image 110 including 21 ′ is captured, and the captured camera image 110 is output to the input detection unit 607 in the form of a digital signal. Of the camera image 110, the red component (0-2
It is represented by a value in the range of 55. Considering that the larger the value, the brighter) the points 6011 ′ and 6021 ′ illuminated by the light from the pointer have a value greater than 0 for the red component. On the other hand, most of the light projected from the projection unit 104 is transmitted in the front direction of the screen by the transmissive screen 103, and a small amount of light is reflected by the screen 103 and enters the camera 105. The red component of the camera image 110 of the part (the part other than the points 6011 ′ and 6021 ′) that is not illuminated by the light projected from is almost zero.

Next, the operation of the input detector 607 will be described. The input detection unit 607 uses the pointer 60 in advance.
The light intensities of points 6011 and 6021 illuminated by 1, 602 are measured and stored. The measuring method is that the control unit 106 controls the screen 103 at the start of use.
The display for sequentially instructing each pointer to project the pointers 601 and 602 on the screen 103 is displayed on the screen 103. Seeing the display, the user lights up the pointer according to the display, and the camera 105 shoots the image. The strengths of the pointers 601 and 602 at that time are stored in the hard disk 134. As a result of the measurement, when the light of the pointer 601 enters the camera 105, a pixel whose red component value is around 200 is detected, and the light of the pointer 602 is emitted by the camera 1.
It is assumed that it has been confirmed that the pixels in which the value of the red component is around 100 are detected when entering 05.

When detecting the input positions of the pointers 601 and 602, the input detection unit 607 checks which pointer has the intensity range of the detected red component value, determines the pointer type, and determines the pointer type. Identify the input position. That is, the input detection unit 607 inspects the red component of the image from the camera 105, determines that it is the light of the pointer 601 if it is between 150 and 255, and determines that it is the light of the pointer 602 if it is between 50 and 150. Judge that it is light. next,
Similar to the first embodiment, the input detection unit 607 compares the current light emission state of the detected light from each of the pointers 601 and 602 with the previous light emission state to determine the event type, and the control unit. The obtained input information is transmitted to 106. In order to make the light emission intensity of the pointer 601 different from that of the pointer 602, a resistor is inserted in series between the light emitting diode 141 and the battery 143 in the circuit of the pointer of FIG. 14, and the magnitude of this resistance is set by the pointer 601 and the pointer 602. It should be different.

The common parts between the constituent elements shown in FIG. 6 and the constituent elements shown in FIG. 1 are designated by the same reference numerals, and detailed description thereof will be omitted.

As described above, according to this embodiment, it is possible for a plurality of users to input operation instructions at the same time in a large-screen display device that uses a pointer for input.

In the first and second embodiments, the screen 10
The image of the projection point of the pointer seen on the back side of 3
I am shooting at 05. At this time, most of the light projected from the projection unit 104 passes through the screen 103. However, when the transparency of the screen is poor, a part of the projected light is reflected toward the back surface of the screen 103, and the projection unit 104 also causes the screen 1 to move toward the back surface of the screen 103.
You can see the image projected on 03. Therefore, as shown on the screen 103 of FIG.
Above the light from the projection unit 104 and the pointers 101, 10
Light from 2 can be seen from the back. Therefore, the camera 105
Receives the reflected light projected from the projection unit 104 and reflected by the screen 103 and the light projected from the pointer at the same time, and both lights are reflected at the same position on the screen and have the same color or intensity. In some cases, the input detection unit cannot recognize the position of the pointer.
Further, when both lights are reflected at different positions on the screen and have the same color or intensity, the input detection unit may misidentify the position of the pointer. The third embodiment described below solves this problem by using polarized light.

A third embodiment of the present invention will be described. The configuration of this embodiment is shown in FIG. In this embodiment, the projection unit 104
Is a right polarizing plate 20 for projecting only clockwise polarized light (hereinafter, referred to as right polarized light) from the projection unit 104 on the front surface thereof.
I am wearing 1. The camera 105 has a left polarizing plate 202 mounted on the front surface thereof so as not to transmit only clockwise polarized light. Details of the polarizing plates 201 and 202 will be described later.

From the projection unit 104, only the light having the right polarization is projected by the right polarizing plate 201, and the screen 103
Projected on. On the other hand, since the camera 105 is equipped with the left polarizing plate 202, the light having only the right polarized light from the projection unit 104 reflected by the screen 103 is reflected by the left polarizing plate 202 on the front surface of the camera 105. It is cut and does not enter the camera 105. The light from the pointers 101 and 102 usually has arbitrary polarization including right polarization and left polarization (counterclockwise polarization). Therefore, the pointers 101 and 10
The second light passes through the screen 103 and is incident on the left polarizing plate 202 on the front surface of the camera 105. This left polarizing plate 20
2, the light with the left polarization out of the light from the pointers 101 and 102 passes through the left polarization plate 202, and the camera 1
It is incident on 05. As a result, on the screen 103,
The image 2011 from the projection unit 104, the pointer 101,
Although there are projection points 1011 and 1021 by the light from 102, the camera images 203 have pointers 101 and 102.
There are only images 1011 'and 1021' of the projection points from.

As described above, the projection unit 104 and the camera 10
By attaching different polarization plates 201 and 202 to the camera 5, light from the projection unit 104 does not enter the camera 105 as shown in the camera image 203 of FIG.
Only the light from 1, 102 is incident. In this way, the camera 105 can shoot only the image of the pointer input by the user without unnecessary light. Input detection unit 107
By inspecting the camera image 203 by the method described in the first embodiment, the input by the pointers 101 and 10 can be detected. Here, the polarizing plate 20
The configuration and operation of 1, 202 will be described with reference to FIGS. FIG. 7 shows the configuration of the right polarizing plate 201.
The right polarizing plate 201 is a linear polarizing plate 20 that passes only linearly polarized light.
15 and a quarter wave plate 2016 for converting linearly polarized light to right polarized light
Composed of. That is, the light 7 emitted from the projection unit 104
Of the 141, only the linearly polarized light 7151 is the linearly polarized light 2
After passing through 015, the linearly polarized light 7151 becomes a quarter wavelength plate 2
By 016, it is changed to right polarized light 7161 and projected on the screen 103.

FIG. 8 shows the structure of the left polarizing plate 202. The left polarizing plate 202 is composed of a quarter-wave plate 2026 that converts right polarized light into linear polarized light, and a linear polarizing plate 2025 whose transmission axis is arranged so as not to pass this linear polarized light. Here, the transmission axis is an axis unique to the linear polarizing plate 2025, and only linearly polarized light having an oscillating surface in the same direction as this axial direction can pass through the linear polarizing plate 2025. For the light entering the quarter-wave plate 2026, the projection unit 104
Right-handed polarization 716 reflected from the screen 103
1 and light 7161 'containing polarized light from pointers 101 and 102 in all directions. Right polarized 7161 and light 7
Right polarized light in 161 ′ is linearly polarized light 7261 and light 7261 ′ including linearly polarized light by the quarter-wave plate 2026.
Can be changed to Since the vibrating surface of the linearly polarized light and the transmission axis of the linearly polarizing plate 2025 are orthogonal to each other, the light 7261 cannot pass through the linearly polarizing plate 2025. Light 725
1 is the light of the light 7261 ′ that has passed through the linear polarization plate 2025.

The linear polarizing plates 2015 and 2025 can be realized by a Glan-Thomson prism, a Nicol prism, a transparent plastic material coated with a dichroic dye material, or the like. The quarter-wave plate can be realized by a crystal plate, barium titanate crystal, or the like. The thickness of the quarter-wave plate is determined according to the wavelength. Regarding the wavelength serving as a reference for determining the thickness, the wavelength of a representative color of the light output from the projection unit 104, the output The average of the upper limit value and the lower limit value of the wavelength of the emitted light, or the weighted average considering the output light amount may be used.

As shown in FIG. 7, in order to change the linearly polarized light to the right polarized light, the transmission axis of the linearly polarizing plate 2015 and 1/4
It is necessary to arrange the wave plate 2016 so as to have a fixed relationship with the fast axis. This is shown in FIG. Here, the fast axis is as follows. Quarter wave plate 2016
Has the directions of two vibrating planes orthogonal to each other, which allows the linearly polarized light incident on the quarter-wave plate 2016 to pass through the quarter-wave plate 2016 without changing its polarization state. Of these two directions, the axis having the same direction as the direction in which the propagation speed of light is higher is called the fast axis.

In FIG. 9, the light 7 emitted from the projection unit 104
141 is, in order, a linear polarization plate 2015 and a quarter-wave plate 2
After passing through 016, the screen 103 and the quarter wave plate 2026, the linear polarization plate 2025 is entered. Further, with respect to the transmission axis 715 of the linear polarization plate 2015, the quarter wavelength plate 20
The 16 fast axes 716 are arranged at 45 degrees counterclockwise as viewed from the quarter-wave plate 2016. Further, as shown in FIG. 8, in order to cut right polarized light that has entered the quarter-wave plate 2026 with the linear polarization plate 2025,
/ 4 wave plate 2026 fast axis 726 and linear polarization plate 20
It is necessary to arrange the 15 transmission axes so as to have a fixed relationship. For this reason, in FIG.
The fast axis 726 of the quarter wavelength plate 2026 is arranged at 45 degrees clockwise with respect to the transmission axis 725 of the quarter wavelength plate 2026.

The common parts between the constituent elements shown in FIG. 2 and the constituent elements shown in FIG. 1 are designated by the same reference numerals, and detailed description thereof will be omitted.

As described above, according to this embodiment, it is possible for a plurality of users to input operation instructions at the same time in a large-screen display device that uses a pointer for input.

By mounting polarizing plates having different polarization characteristics on the front surface of the projection unit 104 and the camera 105, it is possible to prevent the camera from photographing the light from the projection unit 104 reflected on the back side of the screen. , You can shoot the light from the pointer with high accuracy.

In this embodiment, the right polarizing plate and the left polarizing plate are combined, but the present invention is not limited to this, and linear polarizing plates whose transmission axes are orthogonal to each other may be combined. .

Furthermore, in the present embodiment, the quarter-wave plate is used to generate circularly polarized light, but other wave plates may be used to generate elliptical polarized light.

Further, although a plurality of pointers are handled in this embodiment, in the case where there is one kind of pointer, in order to distinguish the light from the pointer from the light from the projection unit, A projection unit having a polarizing plate and a camera may be used.

Further, the projection unit having a polarizing plate and the camera as in this embodiment can be applied to the second embodiment.

Next, a fourth embodiment of the present invention will be described with reference to FIG. In the third embodiment, the rear projection type large display was targeted, but in the present embodiment, the method of the third embodiment is applied to the front projection type large display which is cheaper than the rear projection type large display. is there.

In the case of a front projection display, the projection unit 104 is provided on the front surface of the screen 301. The screen 301 is a reflection type screen, and reflects the light from the projection unit 104 projected from the front surface of the screen 301 to the front surface. The screen 301 is an impermeable sheet, and nothing can be seen when the screen 301 is viewed from the back side. The camera 105 needs to photograph the screen 301 from the front of the screen 301. For this reason,
If you have a front projection display,
The light from the projection unit 104 and the light from the pointers 101 and 102 used by the user to input an instruction or the like are mixed. When the screen 301 is photographed from the front by the camera 105, it is impossible to distinguish whether the light reflected on the screen 301 is the light from the pointer or the light from the projection unit 104. In this embodiment, this problem is solved by using a polarizing plate as in the second embodiment.

FIG. 3 shows the system configuration of the display device according to the present embodiment. As shown in FIG. 3, the projection unit 104 is equipped with a right polarizing plate 201 for projecting only right polarized light from the projection unit 104 on the front surface thereof. The camera 105 has a left polarizing plate 202 mounted on the front surface thereof so as not to transmit only clockwise polarized light. The light emitted from the projection unit 104 is
The right polarizing plate 201 converts the light into right polarized light and reaches the screen 301. The light from the projection unit 104 that is reflected by the screen 301 and enters the camera 105 is filtered by the left polarizing plate 202 in front of the camera 105 and cannot enter the camera 105. On the other hand, the light projected by the user with the pointers 101 and 102 is the screen 3
The left polarizing plate 2 in front of the camera 105 after being reflected by 01.
Filtered by 02. However, the pointer 10
Since the light from 1 and 102 has right polarization and left polarization, the light from the pointer which is left polarization enters the camera 105. As a result, in the camera 105, the camera image 3
02, the light 101 from the pointers 101 and 102
Only 1 ′ and 1021 ′ are photographed, and the light from the projection unit 104 is not photographed. The input detection unit 107 processes the camera image 302 to obtain the pointers 101, 10
The input by 2 can be detected. In addition, the common part between the components shown in FIG. 3 and the components shown in FIG.
The same reference numerals are used and detailed description thereof is omitted.

As described above, according to the present embodiment, even in the case of a large front projection type display, it is possible to perform input using a pointer that projects visible light. In this example,
Although the case of using a plurality of pointers identified by a plurality of colors has been described, even if one pointer is used,
By using the polarizing plate as in this embodiment, it is possible to accurately distinguish the light from the projection unit and the light from the pointer.

Next, a fifth embodiment of the present invention will be described.
In the first to fourth embodiments, a plurality of pointers are distinguished by utilizing the fact that the frequency and intensity of the light from the pointers are different for each pointer. In this embodiment, the plurality of pointers are distinguished by the polarization state of light.

The structure of this embodiment is shown in FIG. In this embodiment, different polarizing plates are installed on the two red pointers. The pointer 101 is provided with a left polarizing plate 401 that transmits only left polarized light, and the pointer 102 is provided with a right polarizing plate 402 that transmits only right polarized light in front of each pointer. As a result, the pointer 101 projects light having left polarization, and the pointer 102 projects light having right polarization.

In front of the camera 105, the input detection unit 407
A variable polarization plate 403 capable of selecting the polarized light to be transmitted from the right polarized light and the left polarized light is installed according to the signal from. As shown in FIG. 10, the variable polarization plate 403 is 1 /
It is composed of a four-wave plate 4037, a half-wave plate 4036, and a linear polarizing plate 4035. 1/2 wave plate 4036
Is composed of TN (Twisted Nematic) liquid crystal, and rotates the direction of the vibrating surface of the incident linearly polarized light by 90 degrees when no voltage is applied. When a predetermined voltage is applied, the direction of the vibration plane of the incident linearly polarized light is not changed.

In FIG. 12, the fast axis 1237 of the quarter-wave plate 4037 and the transmission axis 1235 of the linear polarizing plate 4035.
Indicates the direction of. In this figure, the direction of the fast axis 1237 of the quarter-wave plate 4037 is arranged so that when left-handed polarized light is incident, it changes to linearly-polarized light having an oscillating plane in the vertical direction. That is, the fast axis 1237 is perpendicular to the counterclockwise direction 1201 to 45 when viewed from the incident direction of light.
It is arranged at an angle. Further, the transmission axis 1235 of the linear polarization plate 4035 is arranged in the horizontal direction so that the right polarized light from the pointer 102 is transmitted when a voltage is applied to the ½ wavelength plate 4036.

FIG. 11 shows the left polarized light from the pointer 101,
The right polarization from the pointer 102 is the variable polarization plate 403.
The following shows how the oscillating surface changes due to the quarter-wave plate 4037 and the half-wave plate 4036 when incident on. The vibrating surface of the light after passing through the half-wave plate 4036 is in the vertical direction with respect to the light from the pointer 101 when a voltage is applied. Therefore, the light passes through the linear polarizing plate 4035. That is, the light passes through the variable polarization plate 403. In the drawing, “◯” indicates that the light after passing through the half-wave plate passes through the linear polarizing plate 4035. At this time, the vibrating surface of the light from the pointer 102 does not pass through the linear polarizing plate 4035 because it is in the horizontal direction. That is, it does not pass through the variable polarization plate 403. 1/2 in the figure
“X” indicates that the light after passing through the wave plate does not pass through the linear polarizing plate 4035. When no voltage is applied, the reverse occurs, and the light from the pointer 101 is reflected by the variable polarization plate 403.
, But the light from the pointer 102 does.

The input detection section 407 controls the variable polarization plate 403 to be turned on / off as described above via the variable polarization interface 404 so that only the left polarized light is incident on the camera 105 or only the right polarized light is incident. Can be made incident on the camera 105.

Next, the processing procedure will be described. The input detection unit 407 first detects the input of the pointer 101.
The input detection unit 407 transmits, to the variable polarization plate 403, an off signal indicating that no voltage is applied to the variable polarization plate 403 so that only left polarization is transmitted. The variable polarization plate 403 is
Receiving this signal, it changes so that only the left polarized light is transmitted. Only left polarized light is incident on the camera 105. Therefore, as shown in FIG. 4, only the light from the pointer 101 projecting the left-polarized light enters the camera 105, and the right-polarized light from the pointer 102 does not enter. The camera 105 sends an image showing only the light 1011 ′ from the pointer 101 to the input detection unit 407. The input detection unit 407 is
Similarly to the first embodiment, the image from the camera 105 is sampled frame by frame. Then, for each frame, it is searched whether or not there is a pixel of the color that the light from the pointer 101 has, and the input position of the pointer 101 is searched. On the other hand, in order to detect the light from the pointer 102, the input detection unit 407 changes the polarization characteristic of the variable polarization plate 403 so that only the right polarized light is transmitted, and the camera 105 is set to the pointer 1.
Only the right polarized light projected by 02 is incident.
In this way, the input detection unit 407 detects the position designated by the pointer 102. Next, as in the first embodiment, the input detection unit 407 compares the current light emission state of each detected pointer with the previous light emission state, determines the event type, and inputs it to the control unit 106. Send information.
Note that common parts between the constituent elements shown in FIG. 4 and the constituent elements shown in FIG. 1 are denoted by the same reference numerals, and detailed description thereof will be omitted.

As described above, according to this embodiment, it is possible for a plurality of users to input at the same time in the large-screen input device that uses the pointer for input.

By the way, when inputting with a pointer, it is necessary to know the input position, pointer type, and event type. In the above-described first to fifth embodiments, the event type is distinguished by the generation and disappearance of the projection light of the pointer. However, there are cases in which a large number of event types that cannot be expressed only by the combination of the generation and disappearance of the projected light of the pointer are required. In order to express many event types, a mouse has multiple click buttons. In a sixth embodiment described below, a pointer is provided with a plurality of buttons so that a large number of event types can be expressed by the pointer, and information regarding a plurality of event types identified by the button operation is input and detected from the pointer. Directly to the department wirelessly.

The sixth embodiment of the present invention is shown in FIGS.
Will be explained. In this embodiment, the pointers 501 and 5
02, when the user specifies a large number of event types,
There are as many selection buttons as necessary to specify the event type.

FIG. 5 shows a functional block diagram of the sixth embodiment. The input detection unit 507 includes a reception device (antenna) 503.
The pointer type and the event type are obtained by wireless communication from the pointers 501 and 502 via the.

FIG. 18 shows the hardware configuration of the sixth embodiment. In this embodiment, an RF interface section 181 and an antenna 503 are added to the first embodiment. The input detection unit 507 includes a CPU 131 and a main memory 1
32, the input / output control unit 135, and the RF interface unit 181. RF interface section 18
1 demodulates the RF signal received via the antenna 503, and detects the pointer type and the event type from the demodulated signal. The detected pointer type and event type are stored in the hard disk 134 via the input / output control unit 135.

FIG. 17 shows the internal structure of the pointers 501 and 502. The pointers 501 and 502 are light emitting diodes 141, switches 142, batteries 143, and selection buttons 171, 172, 173 for selecting event types.
A modulator 177 for outputting an RF signal having a modulation frequency corresponding to the selection buttons 171, 172, 173;
An antenna 178 which receives a signal and outputs a radio wave, and resistors 174 and 17 for outputting a high signal when the selection buttons 171, 172, 173 are on and a low signal when they are off.
5,176. User select button 171,1
When either 72 or 173 is selected, the modulation unit 177
Indicates a signal indicating the event type corresponding to the button selected by the user and which pointer 501, 502 transmitted the signal.
And a signal indicating a pointer type for identifying whether or not
An RF signal having a modulation frequency corresponding to this set is output as a set.

The input detection unit 507 obtains the pointer type and the event type by wireless communication from the pointers 501 and 502 via the receiving device (antenna) 503.

On the other hand, according to the method described in the first embodiment, the input detector 507 periodically detects the input position and the pointer type from the camera image and stores the input position for each pointer type. The input detection unit 507 has pointers 501 and 5
When the pointer type and the event information transmitted wirelessly from 02 are received, the input position previously stored in the input detection unit 107 is searched using the pointer type wirelessly transmitted as a key, and the pointer 501 is searched. , 502 are searched for the input position of the pointer type. Next, the input detection unit 507 outputs the searched input position and the transmitted pointer type and event type to the control unit 106 as input information. The control unit 106 performs processing according to the input position from the input detection unit 507, the pointer type, and the event type. Note that common parts between the constituent elements shown in FIG. 5 and the constituent elements shown in FIG. 1 are denoted by the same reference numerals, and detailed description thereof is omitted.

According to the present embodiment, in the large-screen display device for inputting with the pointer, the first, second,
It is possible to define a large number of event types that cannot be realized in 3, 4, and 5. In this embodiment, the case of inputting using a plurality of pointers has been described, but the method of designating the event type of this embodiment can be applied to the case where there is one pointer.

The large screen display device having the pointer according to the present invention can be applied to the plant monitoring system using the large screen display device. For example, with this display device,
Collects information about the state of the monitored plant,
In a plant monitoring system having a plant monitoring computer system for processing, the display device displays the state of the plant, receives an instruction regarding monitoring of the plant, sends the instruction to the plant monitoring computer system, and the plant May be monitored.

The large screen display device having the pointer according to the present invention can be applied to a traffic control system using the large screen display device. For example, in a traffic control system including this display device and a control computer system that collects and processes information about the movement state of an aircraft or an automobile that is a control target, the display device displays the movement state of the aircraft and the like. It is also possible to accept an instruction regarding control of an aircraft or the like and send the instruction to the control computer system to control the aircraft or the like.

The large screen display device having the pointer according to the present invention can be applied to a presentation system using the large screen display device. For example, in a presentation system having this display device and a computer system that outputs information to be presented to the display device, the display device displays the information and sends an accepted input to the computer system for presentation. May be performed.

Further, the large screen display device having the pointer according to the present invention can be applied to the electronic conference system using the large screen display device. For example, in an electronic conferencing system including this display device and a communication device that receives an image to be displayed on the display device from the outside, the display device displays the received image and outputs the received input to the communication device. However, a conference with the outside may be held.

[0123]

According to the present invention, since the input operation is performed by using the pointers that project visible light having different light emission characteristics, it is possible to easily confirm the visible light output by each of the pointers and to perform a plurality of operations. A person can simultaneously perform an input operation on a large screen.

Further, the display device according to the present invention can be used in a system using all large screen display devices. As such a system, for example,
Plant control systems, traffic control systems, presentation systems, electronic conferencing systems, etc.

[Brief description of drawings]

FIG. 1 is a block diagram of a display device according to a first exemplary embodiment of the present invention.

FIG. 2 is a block diagram of a display device according to a second exemplary embodiment of the present invention.

FIG. 3 is a block diagram of a display device according to a third exemplary embodiment of the present invention.

FIG. 4 is a block diagram of a display device according to a fourth exemplary embodiment of the present invention.

FIG. 5 is a block diagram of a display device according to a fifth exemplary embodiment of the present invention.

FIG. 6 is a block diagram of a display device according to a second exemplary embodiment of the present invention.

FIG. 7 is an explanatory diagram showing a configuration of a polarizing plate.

FIG. 8 is an explanatory diagram showing a configuration of a polarizing plate.

FIG. 9 is an explanatory diagram showing an arrangement of a fast axis and a transmission axis of a polarizing plate.

FIG. 10 is an explanatory diagram showing a configuration of a variable polarizing plate.

FIG. 11 is an explanatory diagram showing the operation of the variable polarization plate.

FIG. 12 is an explanatory diagram showing an arrangement of a fast axis and a transmission axis of a variable polarizing plate.

FIG. 13 is a block diagram of hardware of a computer system.

FIG. 14 is a block diagram of a pointer.

FIG. 15 is a processing flow of the input detection unit.

FIG. 16 is a block diagram of a display unit.

FIG. 17 is a block diagram of a pointer.

FIG. 18 is a block diagram of hardware of a computer system.

[Explanation of symbols]

101, 102, 501, 502 ... Pointer, 103 ...
Display screen, 104 ... Projection unit, 105 ... Camera, 1
06 ... control unit, 107 ... input detection unit, 108 ... display unit,
109, 203, 302, 405 ... Camera image, 20
1, 202, 401, 402, 403 ... Polarizing plate, 301
... Front projection display screen, 503 ... Receiver

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Harumi Uchigasaki Inventor Harumi Uchigasaki No. 1-1 Omika-cho, Hitachi City, Ibaraki Hitachi Ltd. Hitachi Research Laboratory (72) Inventor Masayasu Futagawa 7-1, Omika-cho, Hitachi City, Ibaraki Prefecture No. 1 Hitachi Ltd. Hitachi Research Laboratory (72) Inventor Masato Hotta 7-1 Omika-cho, Hitachi City, Ibaraki Prefecture Hitachi Ltd. Hitachi Research Laboratory (72) Inventor Atsuhiko Nishikawa Mika Oita, Ibaraki Prefecture 5-2-1 machi, Hitachi Ltd. Omika factory (72) Inventor Sohei Fukuoka 2-5-1, Omika-cho, Hitachi city, Ibaraki prefecture Hitachi Ltd. Omika factory

Claims (15)

[Claims] 1. A display device comprising: a screen on which an image is displayed; display means for displaying the image by projecting light on the screen; and position specifying means for specifying a position on the screen. In the above, the position designating means projects light for designating the position, which is different from each other in at least one of the color of light, the intensity of light, and the polarization state of light, from the front surface of the screen onto the screen. A plurality of pointers, a camera that receives the plurality of lights projected onto the screen by the plurality of pointers, a position identification unit that identifies the position designated by the pointer by the received light, and the above-mentioned The light has a plurality of colors based on the fact that at least one of the light color, the light intensity, and the polarization state of the light is different from each other. A pointer identifying means for identifying, by each of the identified positions, which one of the pointers the light is projected on. 2. The display device according to claim 1, wherein one of the pointers is configured to output a light emitted from the first light emitting means and the first light emitting means in a first direction. A first polarized light generating means for changing the vibrating surface into a polarized light for rotation, and another one of the pointers is a second light emitting means,
A second polarized light generating means for converting the light output from the second light emitting means into polarized light in which the vibrating surface of the light rotates in a second direction different from the first direction; Has polarization selecting means for selectively selecting and transmitting the polarized light in which the vibrating surface of the light rotates in the first direction and the polarized light in which the vibrating surface of the light rotates in the second direction. A display device, wherein the camera receives the polarized light selected by the polarized light selecting means. 3. The display device according to claim 2, wherein the first polarized light generation means selects a linearly polarized light from the light output from the first light emitting means, and the selected linearly polarized light. A quarter-wave plate arranged to convert linearly polarized light into polarized light that rotates in the first direction, and the second polarized light generation means is one of the light output from the second light emitting means. A linearly polarizing plate that selects only linearly polarized light; and a quarter-wave plate that is arranged to change the selected linearly polarized light into polarized light that rotates in the second direction. It is possible to switch between a quarter wave plate that converts the two types of incident polarized light described above into linearly polarized light having vibration planes orthogonal to each other, and a case where the obtained vibration plane of the linearly polarized light is rotated by 90 degrees and not rotated. Vibrating surface rotating means that can Rolling display device characterized by having a linear polarizing plate for passing either of the two types of polarized light passing through the unit. 4. The display device according to any one of claims 1 to 3, wherein the display means is provided on the back surface of the screen and projects light from the back surface of the screen to display the image. A display device characterized by the above. 5. A screen on which an image is displayed, display means for displaying by projecting light having one polarization state onto the screen, and position specifying means for specifying the position on the screen. The position specifying means includes at least light in a polarization state different from the light projected by the display means on the screen, and is different from each other in at least one of color and intensity of the included light. A plurality of pointers for projecting light for designating a position from the front surface of the screen, a polarization selecting means for selecting and transmitting light in a polarization state different from the light projected by the display means, and the polarization selecting means. A camera that accepts the polarized light selected by, and a position identification unit that identifies the position designated by the pointer based on the received light. Of the light projected on the screen by a number of pointers, the received light is based on the fact that at least one of the color of the light and the intensity of the light is different from each other among the plurality of pointers. A display device, comprising: pointer identifying means for identifying, for each of the identified positions, whether or not the light is projected by a pointer. 6. The display device according to claim 5, wherein the display means is provided on the front surface of the screen and projects light from the front surface of the screen to display the image. . 7. The display device according to claim 5, wherein the display means is provided on the back surface of the screen and projects light from the back surface of the screen to display the image. . 8. A display device according to claim 5, 6 or 7, wherein said display means converts the light emitted from said light emitting means into a polarized light whose vibrating surface rotates in one direction. A display device having a polarized light generation unit for changing the polarized light. 9. The display device according to claim 8, wherein the polarized light generation means selects one of the linearly polarized light of the light output from the light emitting means, and the selected linearly polarized light as one of the linearly polarized light. A quarter-wave plate arranged to convert the polarized light to rotate in a direction, and the polarization selecting means converts the incident polarized light into linear polarized light, and the obtained linear polarized light. A display device having a linear polarizing plate that does not pass light. 10. The display device according to claim 1, wherein each of the pointers has a projection position of the light projected by the pointer on the screen, a polarization state of the light, and A plurality of instructions identified based on at least one of a color of light, an intensity of the light, and a change in a light emission state of the light, and the display device displays the screen of the light projected by the pointer. An instruction identifying means for identifying a plurality of instructions based on at least one of the above projection position, the polarization state of the light, the color of the light, the intensity of the light, and the change of the emission state of the light. A display device characterized by the above. 11. The display device according to claim 1, wherein each of the plurality of pointers receives an identification signal for identifying from other pointers and a data signal in the input means. An input device, comprising: a data transmitting means for transmitting; and the display device having a data receiving means for receiving the identification signal and the data signal. 12. The display device according to any one of claims 1 to 11, and processing means for collecting and processing information regarding a state of a plant to be monitored, the display device comprising: A plant monitoring system, which displays a state of a plant, receives an instruction regarding monitoring of the plant, sends the instruction to the processing means, and monitors the plant. 13. The display device according to any one of claims 1 to 11, and a processing means for collecting and processing information regarding a moving state of a moving body to be controlled, the display device comprising: A control system characterized by displaying a moving state of the moving body, receiving an instruction regarding control of the moving body, sending the instruction to the processing means, and controlling the moving body. 14. A display device according to claim 1, and a processing unit for outputting information to be presented to the display device, the display device displaying the information. A presentation system characterized in that the received input is sent to the above processing means to give a presentation. 15. The display device according to claim 1, and a communication device for externally receiving an image to be displayed on the display device, wherein the display device displays the received image. At the same time, the received input is output to the communication device to hold a conference with the outside, an electronic conference system.