JP2002268807A - Coordinate input device, program for performing coordinate input function and recording medium with the program recorded - Google Patents

Abstract

PROBLEM TO BE SOLVED: To drastically improve the degree of freedom of installation without having to recognize the absolute position of a mapping means. SOLUTION: Optical interruption position information (u11 ,...u51 ) and (u12 ,...u52 ) in sensor heads 1 and 2 at the time when objects are inserted at reference points (x1 and y1 ),...(x5 and y5 ), and reference point coordinates area stored in first storing parts 3 and 4. Coefficient calculating means 5 and 6 calculate coefficients (c11 ,...c51 ) and (c12 ,...c52 ) in each of the sensor heads on the basis of the reference point coordinates and the optical interruption position information and store the coefficients (c11 ,...c51 ) and (c12 ,...c52 ) in second storing part 7 and 8. A prescribed arithmetic operation 9 is performed by using pieces u1 and u2 of information corresponding to optical interruption positions that occur on the respective sensor heads 1 and 2 by the optical interruption objects inserted at the time when coordinates are inputted and the coefficients stored in the second storing parts, and the coordinates (x and y) at which the optical interruption objects are inserted are outputted.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a coordinate input device, and more particularly to a so-called touch panel for inputting a coordinate position indicated by a pointing member such as a pen or a finger to input or select information in a personal computer or the like. The present invention relates to a coordinate input device. This coordinate input device is used integrally with an electronic blackboard and a large display, and is not limited to a form integrated with an electronic display device, such as a wall surface, a paper surface on a desk, or a conventional blackboard, but is written there. Used for devices that digitize information.

[0002]

2. Description of the Related Art FIG. 10 is a diagram showing an appearance of an electronic blackboard system 601. As shown in FIG. 10, an electronic blackboard system 601 as an information input / display system includes an electronic blackboard unit 6 including a plasma display panel (PDP) 602 as a display device and a coordinate input / detection device 603.
04 and a device storage unit 605.

[0003] The device housing section 605 houses a computer such as a personal computer as a control device, a scanner for reading an image of a document, a printer for outputting image data to recording paper, and a video player (FIG. 11). . The PDP 602 is a large screen type (for example, 100 inches or more) that can be used as an electronic blackboard.
Is used. PDP 602 and coordinate input /
The detecting device 603 is provided on the display surface 60 of the PDP 602.
PDP 602
Input / detection device 603 on display surface 602a
The electronic blackboard part 604 is formed such that the coordinate input / detection areas 603a of the electronic blackboard substantially coincide with each other. As described above, the electronic blackboard unit 604 includes the PDP 602 and the coordinate input / detection device 60.
3 is stored and the display surface of the electronic blackboard system 601 (PD
P602 constitutes a display surface 602a) and a writing surface (coordinate input / detection area 603a).

The coordinate input / detection device 603 is provided with a coordinate input / detection device formed by a light flux film projected from at least two or more light sources (not shown) in a radial or fan shape.
It has a coordinate input / detection area 603a, which is a detection surface, and inserts pointing means, such as a fingertip or a pen, into the coordinate input / detection area 603a to insert the coordinate input / detection area 6
By intercepting the light beam in the light receiving element 03a, the designated position is detected by a triangulation method based on the light receiving position of a light receiving element (not shown) such as a CCD, and an optical shielding type coordinate input that enables input of characters and the like. / Detection device is applied. Such an optical shielding type coordinate input / detection device 603
Does not have a physical surface such as a coordinate input surface (touch panel surface).
02 can provide an electronic blackboard system with excellent visibility when used by attaching to the display surface 602a of the display device 02, and provide an inexpensive electronic blackboard system because special materials and mechanisms are not required. Can be.

Further, although not shown, the PDP 602 is provided with a video input terminal and a speaker, and is connected to various information devices and AV devices such as a video player, a laser disk player, a DVD player, and a video camera. The configuration is such that the PDP 602 can be used as a large screen monitor. Also, P
The DP 602 has a display position, width, height,
Adjusting means (not shown) for adjusting distortion and the like
Is also provided.

Next, the electrical connection of each part built in the electronic whiteboard system 601 will be described with reference to FIG. As shown in FIG. 11, the electronic blackboard system 601 includes:
A PDP, a scanner, a printer, and a video player are connected to the computer, and the entire system is controlled by the computer. That is, a display system is configured by the PDP and the computer.
The computer is connected to a controller provided in a coordinate input / detection device 603 for calculating the coordinate position in the coordinate input / detection area 603a designated by the instruction means. The / detection device is also connected to the computer. The electronic whiteboard system 601 can be connected to a network via a computer, and data created by another computer connected to the network can be displayed on a PDP,
The data created by the electronic blackboard system 601 can be transferred to another computer.

FIG. 12 shows the configuration inside the computer.
As shown in FIG. 12, a computer has a CPU that controls the entire system, and a ROM that stores a startup program and the like.
And a RAM used as a work area of the CPU;
A keyboard for inputting characters, numerical values, various instructions, etc., a mouse for moving a cursor and selecting a range, a hard disk, and a PDP connected to the PDP.
A graphics board that controls the display of images to the DP and a network board to connect to the network
Card (or modem), controller, scanner,
Interface (I / F) for connecting a printer etc.
) And a bus for connecting the above components.

[0008] The hard disk has an operating system
A system (OS), a device driver for operating a coordinate input / detection device on a computer via a controller, and various application programs such as drawing software, word processor software, spreadsheet software, and presentation software are stored. .

Further, the computer has a storage medium storing various program codes (control programs) such as an OS, a device driver and various application programs, that is, a floppy (registered trademark) disk, a hard disk, an optical disk (CD-ROM, CD-R,
CD-R / W, DVD-ROM, DVD-RAM, etc.), a magneto-optical disk (MO), a floppy disk drive, a CD-ROM drive, and a MO that read program codes stored in a memory card or the like. A program reading device such as a drive device is mounted.

Various application programs are executed by the CPU under the control of the OS which is started when the power of the computer is turned on. For example, when drawing software is started by a predetermined operation of a keyboard or a mouse, a predetermined image based on the drawing software is displayed on the PDP via a graphics board. The device driver is also started up together with the OS, and enters a state in which data can be input from the coordinate input / detection device via the controller. When the operator inserts the indicating means into the coordinate input / detection area 603a of the coordinate input / detection device 603 in a state where the drawing software is activated, a character or a figure is drawn.
The coordinate information is input to the computer as image data based on the description of the instruction unit, and is displayed as an overwrite image on an image on the screen displayed on the PDP 602, for example. More specifically, the CPU of the computer generates drawing information for drawing a line or character based on the input image data, and provides the drawing information on the graphics board in accordance with the coordinate position based on the input coordinate information. Write to the video memory. After that, graphics
When the board transmits the drawing information written in the video memory to the PDP 602 as an image signal, the same characters as the characters drawn by the operator are displayed on the PDP 602. That is, since the computer recognizes the coordinate input / detection device 603 as a pointing device such as a mouse, the computer performs the same processing as when a character is drawn using a mouse on drawing software. .

(First Embodiment to Which the Present Invention is Applied) FIG. 13 is a diagram showing the configuration of an optical coordinate input device (first embodiment) to which the present invention is applied. The optical coordinate input device 40 includes a light receiving / emitting unit 41, a coordinate input area 43, and a retroreflective member 44. Coordinate input area 4
Reference numeral 3 denotes a rectangular shape, for example, a display surface for electronically displaying characters and images, a whiteboard written with a pen such as a marker, or the like is a coordinate input area.

The optical coordinate input device 40 includes a user's hand made of an optically opaque material on the coordinate input area 43.
This device detects the coordinate position of the pointing object 42 when touched by the pointing object 42 such as a finger, a pen, or a support rod, and inputs the position information to a personal computer or the like.

Light receiving and emitting means 41 are provided at both upper ends of the coordinate input area 43. From the light receiving / emitting means 41 toward the coordinate input area 43, L ₁ , L ₂ , L ₃ ,. . . L _m of the light beam bundle (probe light) is irradiated. Actually, it is a fan-shaped plate-like light wave that spreads from the point light source 61 and travels in parallel to the plane of the coordinate input area.

Further, in the peripheral portion of the coordinate input area 43,
A retroreflective member 44 is provided with the retroreflective surface facing the center of the coordinate input area 43. The retroreflective member 44 is
It is a member having the property of reflecting incident light in the same direction regardless of the angle of incidence. For example, when focusing on a certain beam 47 out of the fan-shaped plate-like light waves emitted from the light emitting / receiving means 41, the beam 47 is reflected by the retroreflecting member 44, and the same light path is again returned as the retroreflected light 46 as the light receiving / emitting means. Proceed back to 41. Light receiving and emitting means 41
Is provided with a light receiving means, as will be described later, and can detect whether or not the return light of each of the probe lights L _{1 to} L _m has returned to the light receiving / emitting means 41.

Now, consider a case where the user touches the position 42 by hand. At this time, the probe light 45 is blocked by the hand at the position 42 and does not reach the retroreflective member 44. Therefore, the return light of the probe light 45 does not reach the light receiving / emitting means 41,
By detecting that the return light corresponding to the probe light 45 is not received, it is possible to detect that the pointing object is inserted on the extension line (straight line L) of the probe light 45.

Similarly, the probe light is emitted from the light receiving / emitting means 41 installed at the upper right of FIG. 13 to detect that the return light corresponding to the probe light 48 is not received. It is possible to detect that the pointing object has been inserted on (straight line R). If the straight line L and the straight line R can be obtained, the coordinates of the intersection where the pointing object 42 such as a hand is inserted can be obtained by calculating the intersection coordinates by calculation.

Next, the configuration of the light receiving / emitting means 41 and a mechanism for detecting which probe light among the probe lights L _{1 to} L _m has been blocked will be described. FIG.
2 shows the internal configuration of FIG. FIG. 14 is a diagram of the light emitting / receiving unit 41 attached to the coordinate input area 43 of FIG. 13 when viewed from a direction perpendicular to the plane of the coordinate input area 43. Here, for simplicity, a two-dimensional plane parallel to the plane of the coordinate input area 43 will be described.

The light receiving / emitting means 41 comprises a point light source 61, a condenser lens 51 and a light receiving element 50. The point light source 61 emits light in a fan shape in a direction opposite to the light receiving element 50 when viewed from the light source. The fan-shaped light emitted from the point light source 61 is considered to be a set of beams traveling in the directions of arrows 53 and 58 and other directions. The beam traveling in the direction of the arrow 53 is reflected by the retroreflective member 55, and the retroreflected light 54 passes through the condenser lens 51 and reaches a position 57 on the light receiving element 50.

The beam traveling along the traveling direction 58 is reflected by the retroreflective member 55, and the retroreflected light 59 reaches the position 56 on the light receiving element 50. The light emitted from the point light source 61 and reflected by the retroreflective member 55 and returning on the same path reaches the different positions 56 and 57 on the light receiving element 50 by the action of the condenser lens 51, respectively. .

Therefore, the pointing object is inserted at a certain position,
When a certain beam is cut off, light does not reach a point on the light receiving element 50 corresponding to the beam. From this,
By examining the distribution of light intensity on the light receiving element 50,
You can see which beam was blocked.

FIG. 15 is a diagram for explaining the operation when the pointing object is inserted and the beam is cut off. In FIG. 15, the light receiving element 50 is provided on the focal plane of the condenser lens 51. Light emitted from the point light source 61 toward the right side in FIG. 15 is reflected by the retroreflective member 55 and returns along the same path. Therefore, the light is condensed again at the position of the point light source 61. The center of the condenser lens 51 is provided so as to coincide with the point light source position. Retroreflective member or 55
Since the returning light from the lens passes through the center of the condenser lens 51, it travels in a symmetrical path behind the lens (on the light receiving element side).

At this time, when the light intensity distribution on the light receiving element 50 is examined, if the pointing object 60 is not inserted, the light intensity distribution on the light receiving element 50 is almost constant, but as shown in FIG. When the pointing object 60 that blocks light is inserted,
Blocked the beam passing therethrough, the position of the position D _n is on the light receiving element 50, the light intensity is weak area (dark spot) occurs.

This position D _n is determined by the emission /
And corresponds to the incident angle theta _n, theta by detecting the D _n
n can be calculated. That theta _n can be represented as theta _n = arctan as a function of D _n (D _n / f) Equation (1). Here, f is the distance between the condenser lens 51 and the light receiving element 50 as shown in FIG. 15, and corresponds to the focal length of the condenser lens 51.

Here, in particular, θ _n in the light receiving / emitting means 41 at the upper left of FIG. 13 is replaced with θ _nL , and D _n is replaced with D _nL . Further, in FIG. 16 illustrating a method of calculating a coordinate position, the pointing object 60 and the coordinate input area 4 are converted by the conversion g of the geometric relative positional relationship between the light emitting / receiving means 41 and the coordinate input area 43.
Angle theta _L of the x-axis of 3, D _{n L} obtained by formula (1)
Θ _L = g (θ _nL ) where θ _nL = arctan (D _nL / f).

Similarly, the light receiving / emitting means 41 at the upper right of FIG.
Is also replaced by the R symbol in the above equation, and the conversion h of the geometric relative positional relationship between the light emitting / receiving means 41 and the coordinate input area 43 on the right side gives θ _R = h (θ _nR ). θ _nR = arctan (D _nR / f) Equation (3) can be expressed.

(Second Embodiment to Which the Present Invention is Applied) Next, an optical coordinate input device (a second embodiment) to which the present invention is applied will be described. This will be described with reference to FIG. 13 used in the first embodiment. The coordinate input area 43 has a quadrangular shape. For example, the coordinate input area may be a display surface that electronically displays characters or images, a whiteboard written with a pen such as a marker, or the like.

The optical coordinate input device 40 includes a user's hand made of an optically opaque material on the coordinate input area 43.
This device detects the coordinate position of the pointing object 42 when touched by the pointing object 42 such as a finger, a pen, or a support rod, and inputs the position information to a personal computer or the like.

Light receiving / emitting means 41 is provided at both upper ends of the coordinate input area 43. From the light receiving / emitting means 41 toward the coordinate input area 43, L ₁ , L ₂ , L ₃ ,. . . L _m of the light beam bundle (probe light) is irradiated. Actually, it is a bundle of light beams that are rotated and scanned by a scanning unit, which will be described later, about the position indicated by the point light source 61.

Further, in the peripheral portion of the coordinate input area 43,
A retroreflective member 44 is provided with the retroreflective surface facing the center of the coordinate input area 43. The retroreflective member 44 is
It is a member having the property of reflecting incident light in the same direction regardless of the angle of incidence. For example, when focusing on a certain beam 47 out of the fan-shaped plate-like light waves emitted from the light emitting / receiving means 41, the beam 47 is reflected by the retroreflecting member 44, and the same light path is again returned as the retroreflected light 46 as the light receiving / emitting means. Proceed back to 41. Light receiving and emitting means 41
Is provided with a light receiving means, as will be described later, and can detect whether or not the return light of each of the probe lights L _{1 to} L _m has returned to the light receiving / emitting means 41.

Now, consider a case where the user touches the position 42 by hand. At this time, the probe light 45 is blocked by the hand at the position 42 and does not reach the retroreflective member 44. Therefore, the return light of the probe light 45 does not reach the light receiving / emitting means 41,
By detecting that the return light corresponding to the probe light 45 is not received, it is possible to detect that the pointing object is inserted on the extension line (straight line L) of the probe light 45.

Similarly, the probe light is emitted from the light receiving / emitting means 41 provided at the upper right of FIG. 13 and the extension of the probe light 48 is detected by detecting that the return light corresponding to the probe light 48 is not received. It is possible to detect that the pointing object has been inserted on (straight line R). If the straight line L and the straight line R can be obtained, the coordinates of the intersection where the pointing object 42 such as a hand is inserted can be obtained by calculating the intersection coordinates by calculation.

Next, the structure of the light receiving / emitting means 41 and a mechanism for detecting which probe light among the probe lights L _{1 to} L _m has been blocked will be described. FIG.
2 shows the internal configuration of FIG. FIG. 17 is a diagram of the light emitting / receiving unit 41 attached to the coordinate input area 43 of FIG. 13 when viewed from a direction perpendicular to the plane of the coordinate input area 43. Here, for simplicity, a two-dimensional plane parallel to the plane of the coordinate input area 43 will be described.

The inside of the light emitting / receiving means 41 is composed of a light source, a polygon mirror and a light receiving element. The light source is a laser light source and emits a collimated beam having a predetermined beam width. The beam diameter is on the order of a few millimeters. The beam emitted from the light source is reflected by the half mirror and enters the polygon mirror. The polygon mirror rotates at a predetermined angular velocity ωt, and rotates and scans the beam emitted from the light source toward the retroreflective element. The beam incident on the retroreflective element returns on the same path as the incident direction, and is reflected by the polygon mirror to reach the half mirror. Of the light that has reached the half mirror, the light that has passed through the half mirror reaches the light receiving element and is converted into an electric signal.

FIG. 18 shows an example of the output signal of the light receiving element. Time t = t0 is the reference position for the rotation of the polygon mirror, and is the time when the beam to be rotationally scanned reaches a predetermined angle. If the pointing object on the coordinate input region is not inserted, the light intensity of Figure 18 shows the I = I _1, the light receiving element pointing object that blocks light is inserted into the coordinate input region is return light not return Therefore, the light intensity becomes I = I ₀ . I =
Assuming that the time when I ₀ is t = t ₁ , the apparent angle θ from the sensor of the pointing object inserted into the coordinate input area is ωΔt. For each of the left and right sensors, t
= T ₀ is the reference position for the rotation of the polygon mirror,
By appropriately selecting in consideration of the relative positional relationship between the sensor and the coordinate input area, θL and θR in FIG. 16 can be obtained.

(Third Embodiment to Which the Present Invention is Applied) Next, an optical coordinate input device (third embodiment) to which the present invention is applied will be described. FIG. 19 shows an optical coordinate input device according to the third embodiment. The coordinate input area has a quadrangular shape, and the coordinate input area is a display surface for electronically displaying an image, a whiteboard written with a pen such as a marker, or the like. By detecting the coordinate position of the pointing object when touching the coordinate input area with the pointing object such as a user's finger, pen, or support rod made of an optically opaque material, the position information is input to a personal computer or the like. Is an optical coordinate input device.

Imaging cameras are mounted on both upper ends of the coordinate input area. The cameras have an imaging angle of view of about 90 degrees, and are installed such that each of them has a coordinate input area as an imaging range. At this time, the optical axis of the imaging camera is parallel to the coordinate input surface and is set at a predetermined distance from the coordinate input surface. In the peripheral part of the coordinate input area, a background plate is mounted with its surface facing the center of the coordinate input area and perpendicular to the coordinate input area surface. The background plate is desirably uniform black.

FIG. 20 shows the relationship between the signal of the imaging camera and the pointing object. When the pointing object is inserted into the coordinate input surface,
This is photographed by the imaging camera, and an image of the pointing object is formed on the imaging element of the imaging camera. When the background plate is black and the pointing object is a finger, the finger has a higher reflectance than the background plate, so that a bright image is formed on a portion corresponding to the pointing object. The light intensity distribution shown in FIG. 20 represents the light intensity distribution of an image on an image sensor (CCD) when a finger is inserted as a pointing object using a black background plate.

At this time, the distance D on the image plane between the center of the optical axis of the imaging camera and the bright image corresponding to the pointing object corresponds to the apparent angle of the pointing object from the principal point of the imaging lens.
θ = D / f. Therefore, by finding D, the apparent distance of the pointing object from the center of the imaging lens can be found. The pointing object may be a dedicated pen with a light emitting element that emits light.

With respect to the left and right imaging cameras shown in FIG.
By determining the apparent angle of the pointing object from the principal point of the imaging camera lens described above, and then performing an appropriate geometric transformation in consideration of the relative positional relationship between the imaging camera and the coordinate input surface, θL , ΘR can be obtained. (Fourth Embodiment to Which the Present Invention is Applied) Next, an optical coordinate input device (fourth embodiment) to which the present invention is applied will be described. FIG. 21 shows an optical coordinate input device according to the fourth embodiment. The coordinate input area has a quadrangular shape, and the coordinate input area is a display surface for electronically displaying an image, a whiteboard written with a pen such as a marker, or the like. By detecting the coordinate position of the pointing object when touching the coordinate input area with the pointing object such as a user's finger, pen, or support rod made of an optically opaque material, the position information is input to a personal computer or the like. Is an optical coordinate input device.

Light receiving and emitting means are mounted on both upper ends of the coordinate input area. The light receiving and emitting means can have the same configuration as the configuration of FIG. 14 shown in the first embodiment. Also,
A configuration similar to the configuration of FIG. 17 shown in the second embodiment may be adopted.

FIG. 22 shows a specific configuration example of the retroreflective pointing object. The pointing object has a pen-like shape, and is preferably made of a material such as rubber or plastic rather than a glossy metal. A retroreflective element is provided near the tip of the pointing object. Even if the incident angle of the light incident on the retroreflective element fluctuates due to the inclination of the pointing object or the like, the light is reflected in the reverse direction on the path of the incident light by the retroreflection. Therefore, when the light emitted from the light receiving / emitting means in FIG. 21 reaches the retroreflective element of the pointing object, the light is reflected recursively and reaches the light receiving portion of the light receiving / emitting means.

FIG. 23 shows an example of a signal when the light receiving / emitting means has the configuration shown in FIG. The fan-shaped light emitted from the point light source 61 is a set of beams traveling rightward in FIG. If the pointing object is not inserted in the fan-shaped beam, the set of beams is not reflected and the light receiving element 50
Does not reach. When the pointing object 60 having retroreflectivity is inserted into the beam, only the beam that has reached the pointing object is reflected and reaches the light receiving element 50. Therefore, a bright peak is formed at a position on the light receiving element corresponding to the beam arrival point. Let D be the peak position on the light receiving element with reference to the intersection between the light receiving lens 51 on the optical axis and the light receiving element.
D corresponds to the apparent angle of the pointing object from the principal point of the light receiving lens, and has a relationship of tan θ = D / f. Therefore, by determining D, the apparent distance of the pointing object from the center of the light receiving lens can be determined. For each of the left and right light emitting and receiving means shown in FIG. 21, the apparent angle of the pointing object from the above-described light receiving lens principal point is obtained, and then the relative positional relationship between the light receiving and emitting means and the coordinate input surface is considered. By performing an appropriate geometric transformation, θL and θR can be obtained.

FIG. 24 shows an example of a signal when the light receiving / emitting means has the configuration shown in FIG. t = t0 is a reference position for the rotation of the polygon mirror, and is a point in time when the beam scanned and rotated reaches a predetermined angle. When the pointing object is not inserted in the coordinate input area, the light intensity in FIG. 24 indicates I = I0. However, when the pointing object that reflects light recursively is inserted in the coordinate input area, the light is returned to the light receiving element. Arrives, the light intensity becomes I = I1. Assuming that the time when I = I1 is t = t1, the pointing object inserted into the coordinate input area is:
The apparent angle θ from the sensor is ωΔt. The reference positions for rotation of the polygon mirror where t = t0 for each of the left and right sensors are appropriately selected in consideration of the relative positional relationship between the sensors and the coordinate input area, thereby obtaining θL and θR in FIG. be able to.

In the above-described first, second, third and fourth embodiments, the spacing between the light receiving and emitting means on the coordinate input area is set to w as shown in FIG. If the x, y coordinate system is as shown in FIG. 16 with the left corner of the origin as shown in FIG. 16, the coordinates (x, y) of the point designated by the pointing means 60 on the coordinate input area 43 are: x = wtan θ _R / ( tan θ _L + tan θ _R ) Expression (4) y = wtan θ _L · tan θ _R / (tan θ _L + tan θ _R ) Expression (5), and x, y are obtained from Expressions (2), (3), (4), and (5).
Can be expressed as a function of D _nL , D _nR .

That is, the positions D _nL and D _nR of the dark spots on the light receiving element 50 of the left and right light emitting / receiving means 41 are detected, and the geometrical arrangement of the light receiving / emitting means 41 is taken into consideration.
The coordinates of the point designated by 0 can be calculated. The above-described coordinate calculation method is based on the principle of triangulation and is described in, for example, Japanese Patent Application Laid-Open No. 9-91094.

[0046]

In the above-mentioned conventional coordinate input device, the coordinates are calculated based on the geometric arrangement of the light receiving and emitting means. Therefore, the coordinates of the coordinate input area can be obtained when the following parameters representing the geometrical arrangement are known. The “light receiving / emitting unit” and the “imaging camera” described in each of the above-described embodiments are referred to as “sensor heads” in the following description.

FIG. 25 is a diagram showing an example in which the sensor head is arranged near the coordinate input area. In this figure, the coordinates x and y obtained from the equations (2) to (5) are coordinates having the point P as the origin. At the stage of calculating these coordinates, it is necessary that the angles θ _offL and θ _offR formed by w and the line segment connecting the optical axes of the sensor heads L and R to the centers of the sensor heads are already known. θ _offL and θ _offR are parameters necessary for the conversion of g and h in equations (2) and (3), respectively.

Further, since the offsets dx and dy due to the parallel movement and the offset θ ₀ due to the rotation in the coordinate system having the origins P and Q are known, the P obtained from the equations (2) to (5) can be used as the origin. Coordinates x,
y can be converted to a coordinate system with Q as the origin of the coordinate input area. Therefore, w, θ _offL , θ _offR , d
It is necessary to determine the mechanical position of the sensor head so that x, dy, θ ₀ are known.

However, in general, assembling the sensor head so that all of these parameters have predetermined values increases the cost in the process of manufacturing the device. Also,
Assemble these parameters within a tight tolerance, measure these parameters after assembly,
There is also a method of reflecting it in the calculation. However, this method is not practical because it involves difficulty in measuring parameters after assembly.

In addition, there is a problem that the above parameters are deviated from the set values at the time of shipment due to vibrations during transportation, and the correct coordinate input operation cannot be performed at the time of delivery. Further, even when the light emitting / receiving device is divided and transported for transportation and packing, the light emitting / receiving device is moved to a coordinate input surface (display surface, blackboard surface, etc.) while maintaining a predetermined positional accuracy at the time of assembly. Need to be re-attached.

However, it is difficult for a general user to perform the mounting again while maintaining the accuracy, or a special jig and mechanism are required, which increases the cost. In addition to this, for example, when an application is considered in which the sensor head portion formed by the light receiving and emitting means is divided into a portable type and the user attaches it to an arbitrary coordinate input surface and is used, a conventional triangulation calculation method is similar. Problems arise and are difficult to implement.

The present invention has been made in view of the problems of the coordinate input device as described above.
It is an object of the present invention to provide a highly reliable coordinate input device that does not require the absolute position of the mapping means to be known and greatly increases the freedom of installation.

Another object of the present invention is to make it possible to construct a highly reliable coordinate input device without having to know the absolute position of the mapping means, to greatly increase the degree of freedom in installation, and to use a simple matrix. An object of the present invention is to provide a coordinate input device that performs a calibration operation that can be executed by calculation or solving a simultaneous equation.

Another object of the present invention is to increase the degree of freedom of the mounting position of the light receiving / emitting means on the coordinate input surface, and to make it easy to use even before the mounting position of the light receiving / emitting means on the coordinate input surface is unknown. An object of the present invention is to provide a coordinate input device that can correctly input coordinates on a coordinate input surface by a calibration operation and is applicable to a retroreflective projection method and a polygon mirror method.

Another object of the present invention is to increase the degree of freedom of the mounting position of the image input means on the coordinate input surface, and even if the mounting position of the light emitting and receiving means on the coordinate input surface is unknown, a simple operation before use. The coordinates on the coordinate input surface can be correctly input by the calibration operation,
An object of the present invention is to provide a coordinate input device applied to an imaging method.

Another object of the present invention is to increase the degree of freedom of the mounting position of the light receiving means or the light emitting means on the coordinate input surface, and to use the light receiving means or the light emitting means even when the mounting position on the coordinate input surface is unknown. An object of the present invention is to provide a coordinate input device which can correctly input coordinates on a coordinate input surface by the previous simple calibration operation and is applied to a pen with a reflection plate.

Another object of the present invention is to increase the degree of freedom of the mounting position of the light emitting and receiving means on the coordinate input surface, and to use the mounting position of the light receiving and emitting means on the coordinate input surface, that is, even when the aforementioned parameters are unknown. With the previous simple calibration operation, the coordinates on the coordinate input surface can be correctly input, and a calibration operation that can be executed by simple matrix calculation or solution of simultaneous equations is performed. The information corresponding to the position of the light blocked by the light blocking means inserted in the coordinates of the, can be calculated by any signal such as a geometric position on the light receiving element or a timing signal for scanning the light receiving element, The process of converting the position of the blocked light into the expected angle of the blocking means and the like can also be omitted. Streamlining, improvement in design freedom of the device, thereby improving the coordinate calculation precision, returning light projection method is to provide a coordinate input apparatus which is applied to the polygon mirror method.

Another object of the present invention is to increase the degree of freedom of the mounting position of the image input means on the coordinate input surface and to use the image input means even when the mounting position of the image input means on the coordinate input surface, that is, the above-mentioned parameter is unknown. With the previous simple calibration operation, the coordinates on the coordinate input surface can be correctly input, and a calibration operation that can be executed by simple matrix calculation or solution of simultaneous equations is performed. The information on the image plane of the image input means input by the image input means corresponding to the indicating means inserted at the coordinates of the coordinate is an arbitrary signal such as a geometric position on the light receiving element or a timing signal for scanning the light receiving element. And converts the position of the information on the image plane of the image input means into the expected angle of the indicating means. Process can also be omitted, the efficiency of significant operations, improving design flexibility of the device, thereby improving the coordinate calculation precision is to provide a coordinate input apparatus which is applied to an imaging system.

Another object of the present invention is to increase the degree of freedom of the mounting position of the light receiving means or light emitting means on the coordinate input surface, and to improve the mounting position of the light receiving means or light emitting means on the coordinate input surface, that is, when the aforementioned parameters are unknown. However, a simple calibration operation before use allows the correct input of coordinates on the coordinate input surface, and a calibration operation that can be performed by simple matrix calculation or solution of simultaneous equations. The information corresponding to the position of the light reflected by the reflecting means inserted at the predetermined coordinates is calculated using an arbitrary signal such as a geometrical position on the light receiving element or a timing signal for scanning the light receiving element. It is possible to omit the process of converting the position of the reflected light into the expected angle of the reflection means, etc. Can, efficiency greatly operations, improving design flexibility of the device, thereby improving the coordinate calculation precision is to provide a coordinate input apparatus which is applied to the reflection plate with a pen.

In the prior art, it is necessary to convert the position indicated by the pointing means on the light receiving means or the image input means into an expected angle from the light emitting / receiving means of the pointing means or the image input means. It was necessary to obtain a conversion table or conversion formula in advance.

Another object of the present invention is to provide information corresponding to the image plane position of the light receiving means of the pointing means or the image input means, that is, the physical position (dip / peak / image plane / image plane) on the light receiving element.
By using (image position) and the like, it is possible to omit the process of creating a conversion table and a conversion formula, to eliminate an error factor generated in this process, and to correspond to the position of the image of the pointing means on the light receiving element. In addition to the physical position of this signal, the coordinates can be calculated using other physical quantities, such as the timing signal for electrical scanning of the light-receiving element, greatly improving the degree of freedom in design. An input device is provided.

In the prior art, it is necessary to convert the position indicated by the pointing means on the light receiving means into an expected angle from the light emitting / receiving means of the pointing means, and a conversion table or conversion formula is obtained in advance. Had to be kept.

Another object of the present invention is to use information corresponding to the image plane position of the light receiving means of the pointing means, that is, the physical position on the light receiving element (the distribution shape portion in the time change of the light intensity of the image plane). As a result, it is possible to omit the process of creating the conversion table and the conversion formula, to eliminate the error factors generated in this process, and to use a signal corresponding to the position of the image of the pointing means on the light receiving element. To provide a coordinate input device capable of performing calculations with other physical quantities such as a timing signal for electrical scanning of a light receiving element, in addition to a general position, and greatly improving the degree of freedom in design. is there.

Another object of the present invention is to calculate a coefficient of a relational expression describing a relation between an arbitrary point in the first coordinate system and a point on the second coordinate system mapped by the mapping means. As a condition under which the coefficients can always be calculated, the coefficient matrix of the simultaneous equations must be non-singular. Therefore, by restricting the way of arranging predetermined reference coordinates, a coordinate input device that always makes this coefficient matrix non-singular Is to provide.

Still another object of the present invention is to provide a calibration mode and a coordinate input mode so that the user can arbitrarily switch the mode when the position of the mapping means shifts during use or immediately after transportation. It is to provide a coordinate input device that can be calibrated by a user himself.

[0066]

According to the present invention, a point on a two-dimensional or three-dimensional first coordinate system is defined on a two-dimensional or one-dimensional second coordinate system different from the first coordinate system. A plurality of mapping means for mapping to a point; a position where a plurality of predetermined coordinates on the first coordinate system are mapped on the second coordinate system by the plurality of mapping means; A plurality of predetermined coordinates on the first coordinate system stored in the first storage means and a plurality of predetermined coordinates on the second coordinate system stored in the first storage means. The relationship between arbitrary coordinates on the first coordinate system and positions mapped on the second coordinate system by the mapping means corresponding to the arbitrary coordinates is described based on the position mapped to the second coordinate system. Coefficient calculating means for calculating the coefficient of the relational expression, and second storing means for storing the calculated coefficient Using a position mapped on the second coordinate system corresponding to an arbitrary coordinate on the first coordinate system, the coefficient stored in the second storage means, and the relational expression, Coordinate calculation means for calculating arbitrary coordinates on the first coordinate system.

In one embodiment of the present invention, the light blocking position information and the reference point coordinates are based on the light blocking position information and the reference point coordinates of the sensor head when the pointing object is inserted into the reference point during calibration. Calculate the coefficient of the relational expression describing the relation. The light-blocking object inserted at the time of inputting coordinates is used to perform a predetermined calculation using the information corresponding to the light-blocking position of light generated in each sensor head and the previously calculated coefficient, thereby inserting the light-blocking object. Output coordinates.

In one embodiment of the present invention, a physical position obtained from the light intensity distribution on the image plane of the light receiving means is used as the light blocking position information.

Further, in one embodiment of the present invention, when calculating the coefficients at the time of calibration, the coefficient matrix needs to be regular, so that the number of reference coordinates is set to 5 and the coordinates of these 5 points are Are arranged so that straight lines connecting the center of the light receiving means and the coordinates of each point do not coincide with each other.

[0070]

DESCRIPTION OF THE PREFERRED EMBODIMENTS One embodiment of the present invention will be specifically described below with reference to the drawings. (Embodiment 1) FIG. 1 shows the configuration of Embodiment 1 of the present invention.
FIG. 2 is a processing flowchart according to the first embodiment of the present invention. The configuration of the present embodiment is similar to that of the first embodiment shown in FIG.
The optical coordinate input device described in FIGS. 3, 14 and 15 and the optical coordinate input device described in FIGS. 13, 17 and 18, which are the second embodiment, are applied.

The “sensor head” in the following description is
It corresponds to the light emitting and receiving means in the first and second embodiments described above. FIG. 1 shows an example in which two sensor heads are installed as shown in FIG. The sensor head L and the sensor head R in FIG. 25 are referred to as a sensor head 1 and a sensor head 2 for convenience of description.

The coordinates of the reference point for calibration are known coordinates on the coordinate input surface, and are represented by (x ₁ ,
y ₁ ), (x ₂ , y ₂ ). . . (X _5, y ₅₎ and (step 101).

For example, in a configuration example in which the coordinate input device of the present invention is installed on an electronic display or on a screen on which a projector is projected, these reference points are provided on a display or on a screen when calibration is performed. Will be displayed as Further, in a conventional whiteboard, blackboard, or the like, a method of setting a reference chart or the like on which predetermined coordinates are printed on the surface, or previously engraving a mark or the like on the board may be considered.

Each of the reference points (x ₁ , y ₁ ), (x ₂ ,
y ₂ ). . . The (x _5, y _5), the pointing object that blocks light fingers are inserted. For example, when a finger is inserted at the reference point (x ₁ , y ₁ ), information corresponding to the light-blocking position (A in FIGS. 15 and 18) of the sensor head 1 caused by the probe light being blocked by the finger. As u ₁₁ . Likewise the blocking position of the light beam in the sensor head 2 and u ₁₂ (Step 1
02).

The first subscript of u corresponds to the subscript of the reference point,
The second subscript corresponds to the number of the sensor head. As u, any information may be used as long as it is information corresponding to the light blocking position shown in FIG.

For example, in the case of the first embodiment, when the light receiving element 50 is a CCD in FIG. 15, as u, a pixel subscript (pixel position number) of the CCD corresponding to the light blocking position is used. Can be. u is C in addition to the pixel subscript
The timing of the signal for scanning the CD, that is, the time from the start of scanning the CCD to the light blocking position may be used.

In the case of the second embodiment, u is a value obtained by performing conversion of ftan ωΔt and ftan ωt1 on the time Δt or time t1 corresponding to the portion A shown in FIG. Here, f is the focal length of the light receiving lens, and ω is the rotational angular velocity of the polygon mirror.

Further, these may be given a predetermined coefficient or offset, and parameters convenient for the design of the apparatus can be arbitrarily used. Considering this, especially the second
In the embodiment of the present invention, Δt or t1 may be used,
Further, tan ωt1 may be set to u without considering the focal length f.

Reference points (x ₁ , y ₁ ), (x ₂ , y ₂ ). . .
(X ₅ , y ₅ )
Light blocking position information (u ₁₁ , u ₂₁ ,..., U ₅₁ ) and (u ₁₂ , u ₁₂ ) in the sensor heads 1 and 2
_22,. . . , U ₅₂ ) and the coordinates of the reference point are stored in the first storage units 3 and 4, respectively (step 103).

Reference point coordinates stored in first storage units 3 and 4
And the light blocking position information are read into the coefficient calculating units 5 and 6.
It is. The coefficient calculation units 5 and 6 calculate the coefficient according to Expression (11) described later.
The coefficient (c₁₁,
c_{twenty one},. . . , C₅₁) And (c)₁₂, C _{twenty two},. . . , C
₅₂) Is calculated (step 104) and stored in the second storage units 7 and 8.
It is stored (step 105).

The operation up to this point is the calibration operation mode, which is indicated by thick arrows in FIG. These series of operations are performed before the user uses the coordinate input device or when the user installs the coordinate input device.

Following the calibration operation mode,
This is an operation mode for inputting coordinates. Hereinafter, the coordinate input operation will be described.

Light is blocked by the sensor heads 1 and 2 by a light blocking object such as a finger inserted into the coordinate input surface. That is, in the same manner as described in the calibration mode, the information u ₁ and u ₂ corresponding to the light blocking position are acquired by the sensor heads 1 and 2 (step 106).

Further, the above-described calibration operation
In the mode, the coefficient (c) stored in the second storage units 7 and 8
₁₁, C_{twenty one},. . . , C₅₁) And (c)₁₂,
c_{twenty two},. . . , C ₅₂) Is read (step 10)
7), the coordinate calculator 9 calculates u₁, U_TwoAnd (c₁₁,
c _{twenty one},. . . , C₅₁) And (c)₁₂, C_{twenty two},. . . , C
₅₂) Is used to calculate the coordinates according to equation (14) described below.
(Step 108), a seat into which a light blocking object such as a finger is inserted
Outputs the mark (x, y) to a personal computer (not shown)
(Step 109).

In the processing flowchart of FIG. 2, for example, the calibration operation mode of the sensor head 1 (steps 101 to 105) and the calibration operation mode of the sensor head 2 (steps 101 to 1)
05) are performed in parallel, and then the coordinate calculation mode (steps 106 to 109) is executed. The calibration operation mode of the sensor head 1 is executed, and then the calibration operation mode of the sensor head 2 is executed. And then execute the coordinate calculation mode.

(Embodiment 2) FIG. 1 shows the configuration of Embodiment 2 of the present invention, which is the same as Embodiment 1. FIG. 2 is a processing flowchart according to the second embodiment of the present invention, which is similar to the first embodiment. The configuration of the present example is applied to the optical coordinate input device described in the third embodiment with reference to FIG.

The “sensor head” in the following description is
It is assumed that it corresponds to the imaging camera in the third embodiment described above. FIG. 1 shows an example in which two sensor heads are installed as shown in FIG. The sensor head L and the sensor head R in FIG. 25 are referred to as a sensor head 1 and a sensor head 2 for convenience of description.

The coordinates of the reference point for calibration are known coordinates on the coordinate input surface, and are represented by (x ₁ ,
y ₁ ), (x ₂ , y ₂ ). . . (X _5, y ₅₎ and (step 101).

For example, in a configuration example in which the coordinate input device of the present invention is installed on an electronic display or on a screen on which a projector is projected, these reference points are provided on a display or on a screen when calibration is performed. Will be displayed as Further, in a conventional whiteboard, blackboard, or the like, a method of setting a reference chart or the like on which predetermined coordinates are printed on the surface, or previously engraving a mark or the like on the board may be considered.

Each of the reference points (x ₁ , y ₁ ), (x ₂ ,
y ₂ ). . . The (x _5, y _5), the pointing object that blocks light fingers are inserted. For example, when a finger is inserted at the reference point (x ₁ , y ₁ ), let u ₁₁ be information corresponding to an image position (A in FIG. 20) formed on the imaging surface of the sensor head 1. Similarly, the image position of the pointing of the sensor head 2 and u ₁₂ (step 102).

The first subscript of u corresponds to the subscript of the reference point,
The second subscript corresponds to the number of the sensor head. As u, any information may be used as long as it corresponds to the image position of the pointing object shown in FIG.

For example, in the case of the third embodiment, when the light receiving element is a CCD in FIG. 20, u represents a pixel subscript (pixel position number) of the CCD corresponding to the image position of the pointing object.
Etc. can be used. u is a CCD in addition to the pixel subscript
, Or the time from the start of scanning the CCD to the image position of the pointing object.

Further, these may be given a predetermined coefficient or offset, and parameters convenient for the design of the apparatus can be arbitrarily used.

Reference points (x ₁ , y ₁ ), (x ₂ , y ₂ ). . .
(X ₅ , y ₅ )
The image position information (u ₁₁ , u ₂₁ ,..., U ₅₁ ) of the pointing object in the sensor heads 1 and 2 and (u ₁₁ )
_12, u _22,. . . , U ₅₂ ) and the coordinates of the reference point are stored in the first storage units 3 and 4, respectively (step 103).

Reference point coordinates stored in first storage units 3 and 4
And the image position information of the pointing object are read by the coefficient calculation units 5 and 6.
It is impregnated. The coefficient calculators 5 and 6 calculate the following equation (11).
And the coefficient (c₁₁,
c_{twenty one},. . . , C₅₁) And (c) ₁₂, C_{twenty two},. . . , C
₅₂) Is calculated (step 104) and stored in the second storage units 7 and 8.
It is stored (step 105).

The operation up to this point is the calibration operation mode, which is indicated by thick arrows in FIG. These series of operations are performed before the user uses the coordinate input device or when the user installs the coordinate input device.

Following the calibration operation mode,
This is an operation mode for inputting coordinates. Hereinafter, the coordinate input operation will be described.

The pointing object such as a finger inserted into the coordinate input surface generates an image of the pointing object on the image plane of each of the sensor heads 1 and 2. That is, in the same manner as described in the calibration mode, information u ₁ corresponding to the image position of the pointing object,
u ₂ is acquired by each of the sensor heads 1 and 2 (step 1).
06).

Further, the above-described calibration operation
In the mode, the coefficient (c) stored in the second storage units 7 and 8
₁₁, C_{twenty one},. . . , C₅₁) And (c)₁₂,
c_{twenty two},. . . , C ₅₂) Is read (step 10)
7), the coordinate calculator 9 calculates u₁, U_TwoAnd (c₁₁,
c _{twenty one},. . . , C₅₁) And (c)₁₂, C_{twenty two},. . . , C
₅₂) Is used to calculate the coordinates according to equation (14) described below.
(Step 108), coordinates where the pointing object such as a finger is inserted
(X, y) is output to a personal computer (not shown).
Step 109).

(Embodiment 3) FIG. 1 shows the configuration of Embodiment 3 of the present invention, which is the same as Embodiments 1 and 2. FIG. 2 is a processing flowchart according to the third embodiment of the present invention, which is similar to the first and second embodiments. The configuration of the present embodiment is applied to the optical coordinate input device described in the fourth embodiment with reference to FIG.

The “sensor head” in the following description is
It corresponds to the light receiving / emitting means in the fourth embodiment described above. FIG. 1 shows an example in which two sensor heads are installed as shown in FIG. The sensor head L and the sensor head R in FIG. 25 are referred to as a sensor head 1 and a sensor head 2 for convenience of description.

The coordinates of the reference point for calibration are known coordinates on the coordinate input surface, and are represented by (x ₁ ,
y ₁ ), (x ₂ , y ₂ ). . . (X _5, y ₅₎ and (step 101).

For example, in a configuration example in which the coordinate input device of the present invention is installed on an electronic display or on a screen on which a projector is projected, these reference points are set to predetermined marks on the display or on the screen during the calibration operation. Will be displayed as Further, in a conventional whiteboard, blackboard, or the like, a method of setting a reference chart or the like on which predetermined coordinates are printed on the surface, or previously engraving a mark or the like on the board may be considered.

Each of the reference points (x ₁ , y ₁ ), (x ₂ ,
y ₂ ). . . At (x ₅ , y ₅ ), the pointing object provided with the retroreflective element is inserted. For example, the reference point (x ₁ ,
When the pointing object is inserted into y ₁ ), the reflected light position information corresponding to the position (A in FIG. 23) of the pointing object formed on the image plane of the sensor head 1 is denoted by u ₁₁ . Similarly, the reflected light position information corresponding to the position of the pointing formed on the image plane of the sensor head 2 and u ₁₂ (step 102).

The first subscript of u corresponds to the subscript of the reference point,
The second subscript corresponds to the number of the sensor head. As u, any information may be used as long as it corresponds to the position of the pointing object shown in FIG.

For example, in the case of the fourth embodiment, when the light receiving element is a CCD in FIG. 23, u is a pixel subscript (pixel position number) of the CCD corresponding to the position of the pointing object (A in FIG. 23). ) Can be used. u is the timing of the signal for scanning the CCD, that is, CC
The time from the start of scanning of D to the position of the image of the pointing object may be used.

Further, these may be given a predetermined coefficient or offset, and parameters convenient for the design of the apparatus can be arbitrarily used.

Reference points (x ₁ , y ₁ ), (x ₂ , y ₂ ). . .
(X ₅ , y ₅ )
The reflected light position information (u ₁₁ ,
u ₂₁ ,. . . , U ₅₁ ) and (u ₁₂ , u ₂₂ ,.
₅₂ ) and the coordinates of the reference point are stored in the first storage units 3 and 4, respectively (step 103).

The reference point coordinates and the reflected light position information stored in the first storage units 3 and 4 are read into the coefficient calculation means 5 and 6. The coefficient calculating means 5 and 6 calculate the coefficient (c ₁₁ ,
c ₂₁ ,. . . , C ₅₁ ) and (c ₁₂ , c ₂₂ ,..., C
₅₂ ) is calculated (step 104) and stored in the second storage units 7 and 8 (step 105).

The operation up to this point is the calibration operation mode, which is indicated by thick arrows in FIG. These series of operations are performed before the user uses the coordinate input device or when the user installs the coordinate input device.

Following the calibration operation mode,
This is an operation mode for inputting coordinates. Hereinafter, the coordinate input operation will be described.

A retroreflecting light is generated at each of the sensor heads 1 and 2 by the pointing object having the retroreflective element inserted into the coordinate input surface. That is, information u ₁ and u ₂ corresponding to the position of the pointing object are acquired by the sensor heads 1 and ₂ in the same manner as described in the calibration mode (step 106).

Further, the above-described calibration operation
In the mode, the coefficient (c) stored in the second storage units 7 and 8
₁₁, C_{twenty one},. . . , C₅₁) And (c)₁₂,
c_{twenty two},. . . , C ₅₂) Is read (step 10)
7), the coordinate calculator 9 calculates u₁, U_TwoAnd (c₁₁,
c _{twenty one},. . . , C₅₁) And (c)₁₂, C_{twenty two},. . . , C
₅₂) Is used to calculate the coordinates according to equation (14) described below.
(Step 108), coordinates where the pointing object such as a finger is inserted
(X, y) is output to a personal computer (not shown).
Step 109).

The calculation of the coefficients and the calculation of the coordinates will be described in detail below. In general, a camera system shoots an object in a three-dimensional space and records the image on a two-dimensional film surface. FIG. 3 is a diagram illustrating the concept of a camera system.
(X, y, z) is the object space coordinates, and p (x, y, z) is the position of the object. (U, v) is the image space coordinates,
This is a coordinate system representing the position of the image on the image plane. The point r is the principal point position of the lens. The point p in the three-dimensional object space is converted into a point q in the two-dimensional image space by a mapping f via a lens. Ie

(Equation 7) If the mapping f at this time can be estimated, the position of the object in the three-dimensional object space can be estimated from the position of the image on the two-dimensional film surface by using the inverse mapping of the mapping f.

Here, the camera system corresponds to the light receiving lens system and the imaging camera system described in the first and third embodiments. Further, as described in the first embodiment, the value obtained by performing the conversion of ftanωΔt or ftanωt1 with respect to the time Δt or time t1 corresponding to A shown in FIG. 18 also in the rotary scanning system described in the second embodiment. By setting u to u, it is possible to treat this as equivalent to the camera system, and it is possible to estimate the mapping according to the following description and calculate the coordinates from the estimated mapping.

In general, the mapping f is represented by Expressions (6) and (7) (for example, see Xu Jiang, 3D Vision, p79, Kyoritsu Shuppan, 1998).

[0117]

(Equation 8)

(Equation 9) Here, a coordinate input system in the above-described optical coordinate input device to which the present invention is applied will be considered. In this coordinate system, the object space is two-dimensional, and the image space is one-dimensional. That is, the object space is a coordinate input area and is constrained on a plane. In the first and third embodiments, the image space is a straight line parallel to the coordinate input surface on the one-dimensional CCD or the two-dimensional CCD, and is constrained on a straight line along the CCD pixel array. In the second embodiment, since the time-series change of the signal on the light receiving element due to the rotational scanning is u, this is also restricted to one dimension.

That is, the general formulas (6) and (7)
Then, the u axis of the image space is the same plane as the xy plane of the object space.
Assume that Therefore, equations (6) and (7) are
Number c _Four, C₉, C_TenAnd c_Three, C_Four, C_FiveAnd rewritten as
It is expressed as (8) and further expanded to obtain equation (9)
You.

(Equation 10) c ₁ x + c ₂ y + c ₃ −c ₄ ux−c ₅ uu = u Equation (9)

The equation (9) is expressed by the coordinates (x,
This is an equation that relates y) to u obtained from the sensor head of the embodiment to which the present invention is applied. Where c ₁ ,
c ₂ , c ₃ , c ₄ , and c ₅ are coefficients, and exist for each sensor head. In the above-described calibration operation mode, this coefficient is determined for each sensor head.

Hereinafter, the method of determining these coefficients will be described.
Coefficient c of the n-th sensor head_1n, C_2n,. . . c
_5nIs obtained as follows. That is, m known
The point p₁(X₁, Y₁), P_Two(X_Two, Y_Two) ,. . . p
_m(X_m, Y_m) And the corresponding n-th sensor head.
Image position q_1n(U _1n), Q_2n(U_2n) ,. . .
q_mn(U_mn), From equation (9), the following simultaneous equations
An expression is obtained.

[Equation 11]Since there are five unknown coefficients, m = 5 in equation (10) and five
For the known point p, the corresponding image plane position q
Ask for. In the coefficient calculation units 5 and 6 in FIG.
0) according to equation (11)
｛C_1n, C_2n,. . . c _5n演算 is calculated for each sensor head
Then, the data is stored in the second storage units 7 and 8.

(Equation 12)

Next, a method of calculating coordinates in the coordinate input operation mode will be described. Let n be the number of sensor heads and the coefficients for each sensor head be c _1i , c _2i , c _3i ,
Let c _4i , c _5i (i = 1, 2,... n). Also, n
The image positions in the sensor heads are denoted by u ₁ , u ₂ ,. . . u
_Let it be _n .

From equation (9), the object space coordinates (coordinates on the coordinate input plane) (x, y) satisfy the simultaneous equations of equation (12).

(Equation 13) Therefore, the object coordinates (x, y) on the coordinate input area can be obtained by solving equation (12) and using equation (13).

[Equation 14]

In the embodiment to which the present invention is applied,
Since the coordinate input device has two sensor heads, n
= 2. In the coordinate calculation unit 9 of FIG.
= 2, the coordinates (x, y) on the coordinate input surface where the pointing object such as a finger is inserted are calculated and output in accordance with Expression (14).

(Equation 15) (Embodiment 4) FIG. 4 shows the configuration of Embodiment 4 of the present invention.
FIG. 5 is a processing flowchart according to the fourth embodiment of the present invention. The configuration of the present embodiment is similar to that of the first embodiment shown in FIG.
This is applied to the optical coordinate input device described in 3, 14, and 15. FIG. 4 shows the case where the sensor head is 2 as shown in FIG.
The following shows an example in which one is installed.

The coordinates of the reference point for calibration are known coordinates on the coordinate input surface, and are represented by (x ₁ ,
y ₁ ), (x ₂ , y ₂ ). . . (X _5, y ₅₎ and (step 201).

For example, in a configuration example in which the coordinate input device of the present invention is installed on an electronic display or on a screen on which a projector is projected, these reference points are provided at predetermined marks on the display or on the screen during the calibration operation. Will be displayed as Further, in a conventional whiteboard, blackboard, or the like, a method of setting a reference chart or the like on which predetermined coordinates are printed on the surface, or previously engraving a mark or the like on the board may be considered.

Each of these reference points (x ₁ , y ₁ ), (x ₂ ,
y ₂ ). . . To (x _5, y _5), to insert an object, each blocking light finger as indicating means. At this time, the light intensity distribution (FIG. 15) on the sensor head image plane is output from the sensor head. The output intensity distribution is sent to the dip position information detecting units 10 and 11, where the dip position information is obtained. The dip indicates the position of a dark spot due to light blocking in the light intensity distribution. The dip position information can be obtained by, for example, setting a predetermined threshold value, searching for two positions on the light receiving element at a point where the light intensity crosses the threshold value, and using the average of the positions as the dip position. Conceivable. Further, as another method, a method of adding the position on the light receiving element of the point where the light intensity becomes larger than the predetermined threshold value and dividing the sum by the number of additions to obtain the center of gravity of the dip position can be considered.

The information corresponding to the position on the light receiving element surface corresponding to the horizontal axis of the light intensity distribution described above does not need to be the actual scale position on the light receiving element surface, but corresponds to the light blocking position. Any information may be used as long as the information is provided. Further, u may be given an arbitrary coefficient or offset, and any parameter convenient for the design of the apparatus can be arbitrarily used.

When a finger is inserted at the reference point (x ₁ , y ₁ ),
The information output by the dip position information detecting unit 10 and u _11. Similarly, the light blocking position of the sensor head 2 is set to u ₁₂
And The first subscript of u corresponds to the reference point subscript, and the second subscript corresponds to the sensor head number.

Reference points (x ₁ , y ₁ ), (x ₂ , y ₂ ). . .
Dip position information (u ₁₁ , u ₁₁₎ detected by the dip position information detection units 10 and 11 of the sensor head 1 and the sensor head 2 when an object is inserted into (x ₅ , y ₅ ), respectively.
u ₂₁ ,. . . , U ₅₁ ) and (u ₁₂ , u ₂₂ ,.
₅₂ ) and the coordinates of the reference point are stored in the first storage units 3 and 4, respectively (step 203).

The reference point coordinates and the dip position information stored in the first storage units 3 and 4 are read by the coefficient calculating means 5 and 6, and the coefficient (c ₁₁ ,
c ₂₁ ,. . . , C ₅₁ ) and (c ₁₂ , c ₂₂ ,..., C
₅₂ ) is calculated (step 204) and stored in the second storage units 7 and 8 (step 205).

The operation up to this point is the calibration operation mode. Before the user uses the coordinate input device,
Alternatively, the operation is performed when a coordinate input device is installed. Subsequent to the calibration operation mode, the operation mode is for inputting coordinates.

A light blocking object such as a finger inserted into the coordinate input surface causes a dip in each of the sensor heads 1 and 2 due to light blocking. The dip position information detection units 10 and 11 of the sensor head 1 and the sensor head 2 detect dip position information u ₁ and u ₂ corresponding to the light speed cutoff position (step 206).

Furthermore, the above-described calibration operation
In the mode, the coefficient (c) stored in the second storage units 7 and 8
₁₁, C_{twenty one},. . . , C₅₁) And (c)₁₂,
c_{twenty two},. . . , C ₅₂) Is read (step 20)
7), the coordinate calculator 9 calculates u₁, U_TwoAnd (c₁₁,
c _{twenty one},. . . , C₅₁) And (c)₁₂, C_{twenty two},. . . , C
₅₂) Is calculated in the same manner as in each of the above-described embodiments.
(Step 208) A seat into which a light blocking object such as a finger is inserted.
The target (x, y) is output (step 209).

(Embodiment 5) FIG. 6 shows the configuration of Embodiment 5 of the present invention. FIG. 5 is a processing flowchart according to the fifth embodiment of the present invention, which is similar to the fourth embodiment. The configuration of this example is applied to the optical coordinate input device described in the third embodiment with reference to FIGS. FIG. 6 shows an example in which two sensor heads are installed as shown in FIG.

The coordinates of the reference point for calibration are known coordinates on the coordinate input surface, and are represented by (x ₁ ,
y ₁ ), (x ₂ , y ₂ ). . . (X _5, y ₅₎ and (step 201).

For example, in a configuration example in which the coordinate input device of the present invention is installed on an electronic display or on a screen on which a projector is projected, these reference points are provided on a display or on a screen when calibration is performed. Will be displayed as Further, in a conventional whiteboard, blackboard, or the like, a method of setting a reference chart or the like on which predetermined coordinates are printed on the surface, or previously engraving a mark or the like on the board may be considered.

At each of these reference points, a pointing object such as a finger is inserted as pointing means. At this time, the sensor head 1,
2 outputs the light intensity distribution on the image plane of the sensor head (FIG. 20). The output intensity distribution is sent to peak position information detectors 19 and 20, where peak position information is obtained. The peak indicates the position of a bright point in the light intensity distribution due to the image of the pointing object. The peak position information can be obtained by, for example, setting a predetermined threshold value, searching for two positions on the light receiving element at a point where the light intensity crosses the threshold value, and using the average of the positions as the peak position. Conceivable. As another method, a method of adding the position on the light receiving element of the point where the light intensity becomes larger than the predetermined threshold value and dividing the sum by the number of additions to obtain the center of gravity of the peak position can be considered.

The information corresponding to the position on the light receiving element surface corresponding to the horizontal axis of the light intensity distribution described above does not need to be the actual scale position on the light receiving element surface, but corresponds to the light blocking position. Any information may be used as long as the information is provided. As u, any coefficient or offset may be applied, and parameters convenient for the design of the apparatus can be arbitrarily used.

When a finger is inserted at the reference point (x ₁ , y ₁ ),
The information output by the peak position information detecting unit 19 and u _11. Similarly the peak position of the sensor head 2 and u _12. The first subscript of u corresponds to the reference point subscript, and the second subscript corresponds to the sensor head number.

The reference point (x₁, Y₁), (X_Two, Y_Two). . .
(X_Five, Y_Five), When each object is inserted,
Peak position information detection of sub head 1 and sensor head 2
The peak position information (u₁₁,
u_{twenty one},. . . , U₅₁) And (u) ₁₂, U_{twenty two},. . . , U
₅₂) And the coordinates of the reference point are stored in the first storage units 3 and 4, respectively.
It is stored (step 203).

The reference point coordinates and the peak position information stored in the first storage units 3 and 4 are read by the coefficient calculation means 5 and 6, and the coefficient (c ₁₁ ,
c ₂₁ ,. . . , C ₅₁ ) and (c ₁₂ , c ₂₂ ,..., C
₅₂ ) is calculated (step 204) and stored in the second storage units 7 and 8 (step 205).

The operation up to this point is the calibration operation mode, and before the user uses the coordinate input device,
Alternatively, the operation is performed when a coordinate input device is installed. Subsequent to the calibration operation mode, the operation mode is for inputting coordinates.

Light blocking object such as a finger inserted into the coordinate input surface
Light from the image of the pointing object by each sensor head 1 and 2
An intensity peak occurs. Sensor head 1 and sensor
In the peak position information detection units 19 and 20 of the
Information u corresponding to the image position of the body ₁, U_TwoIs detected (step
206).

Further, the above-described calibration operation
In the mode, the coefficient (c) stored in the second storage units 7 and 8
₁₁, C_{twenty one},. . . , C₅₁) And (c)₁₂,
c_{twenty two},. . . , C ₅₂) Is read (step 20)
7), the coordinate calculator 9 calculates u₁, U_TwoAnd (c₁₁,
c _{twenty one},. . . , C₅₁) And (c)₁₂, C_{twenty two},. . . , C
₅₂) Is calculated in the same manner as in each of the above-described embodiments.
(Step 208), coordinates where the pointing object such as a finger is inserted
(X, y) is output (step 209).

(Embodiment 6) FIG. 4 shows the configuration of Embodiment 6 of the present invention. In the present embodiment, a portion having a predetermined distribution shape in the time change of the light intensity in the light receiving means is used as the information corresponding to the coordinates designated by the designation means. The configuration of this embodiment is applied to the optical coordinate input device described in the second embodiment with reference to FIGS. FIG. 4 shows an example in which two sensor heads are installed as shown in FIG.

The coordinates of the reference point for calibration are known coordinates on the coordinate input surface, and are represented by (x ₁ ,
y ₁ ), (x ₂ , y ₂ ). . . And (x _5, y _5).

For example, in a configuration example in which the coordinate input device of the present invention is installed on an electronic display or on a screen on which a projector is projected, these reference points are provided at predetermined marks on the display or on the screen during the calibration operation. Will be displayed as Further, in a conventional whiteboard, blackboard, or the like, a method of setting a reference chart or the like on which predetermined coordinates are printed on the surface, or previously engraving a mark or the like on the board may be considered.

Each of these reference points (x ₁ , y ₁ ), (x ₂ ,
y ₂ ). . . To (x _5, y _5), to insert an object, each blocking light finger as indicating means. At this time, the light intensity distribution (FIG. 18) on the sensor head image plane is output from the sensor head. The output intensity distribution is sent to the dip position information detecting unit, where the dip position information is obtained. The dip indicates a position of a dark spot (a portion having a predetermined distribution shape in a temporal change in light intensity) due to light blocking in the light intensity distribution. The dip position information can be obtained by, for example, setting a predetermined threshold value, searching for two positions on the light receiving element at a point where the light intensity crosses the threshold value, and using the average of the positions as the dip position. Conceivable. Further, as another method, a method of adding the position on the light receiving element of the point where the light intensity becomes larger than the predetermined threshold value and dividing the sum by the number of additions to obtain the center of gravity of the dip position can be considered.

The information corresponding to the position on the light receiving element surface corresponding to the horizontal axis of the light intensity distribution described above does not need to be the actual scale position on the light receiving element surface, but corresponds to the light blocking position. Any information may be used as long as the information is provided. For example, in FIG. 18, the time t1 corresponding to the light-blocking position is converted to ta.
nωt1 can be used as u. Further, u may be given an arbitrary coefficient or offset, and any parameter convenient for the design of the apparatus can be arbitrarily used.

When a finger is inserted at the reference point (x ₁ , y ₁ ),
The information output by the dip position information detection unit and u _11. Likewise the blocking position of the light beam in the sensor head 2 and u _12. The first subscript of u corresponds to the reference point subscript, and the second subscript corresponds to the sensor head number.

Reference points (x ₁ , y ₁ ), (x ₂ , y ₂ ). . .
Dip position information (u ₁₁ , u ₁₁₎ detected by the dip position information detection units 10 and 11 of the sensor head 1 and the sensor head 2 when an object is inserted into (x ₅ , y ₅ ), respectively.
u ₂₁ ,. . . , U ₅₁ ) and (u ₁₂ , u ₂₂ ,.
₅₂ ) and the coordinates of the reference point are stored in the first storage units 3 and 4, respectively.

The reference point coordinates and dip (dark point) position information stored in the first storage units 3 and 4 are stored in the coefficient calculating unit 5.
6 and a coefficient (c
₁₁ , c21 _,. . . , C ₅₁ ) and (c ₁₂ ,
c ₂₂ ,. . . , C ₅₂ ) are calculated and stored in the second storage units 7 and 8.

The operation up to this point is the calibration operation mode. Before the user uses the coordinate input device,
Alternatively, the operation is performed when a coordinate input device is installed. Subsequent to the calibration operation mode, the operation mode is for inputting coordinates.

A light blocking object such as a finger inserted into the coordinate input surface causes a dip in each of the sensor heads 1 and 2 due to light blocking. The dip position information detectors 10 and 11 of the sensor head 1 and the sensor head 2 detect dip position information u ₁ and u ₂ corresponding to the cutoff position of the speed of light.

Further, the above-described calibration operation
In the mode, the coefficient (c) stored in the second storage units 7 and 8
₁₁, C_{twenty one},. . . , C₅₁) And (c)₁₂,
c_{twenty two},. . . , C ₅₂) Is read out, and the coordinate calculation unit 9
u₁, U_TwoAnd (c₁₁, C_{twenty one},. . . , C₅₁)and
(C₁₂, C_{twenty two},. . . , C₅₂) Using
Calculation is performed in the same manner as in the embodiment, and a light blocking object such as a finger is inserted.
The coordinates (x, y) are output.

(Embodiment 7) Embodiment 7 is an embodiment relating to the number of calibration points and the arrangement of sensor heads. FIG. 7 is a diagram illustrating the seventh embodiment. In the figure, the paper surface corresponds to the coordinate input surface.

Points p1, p2, p3, p on the coordinate input plane
Reference numerals 4 and p5 are the reference points for calibration described above whose coordinates are known. Point o is the center of one of the plurality of sensor heads. More precisely, it is the object-side principal point of the light receiving lens.

As described above, when the coefficients are calculated by the equation (10), the condition that the coefficients can always be calculated is that the coefficient matrix of the simultaneous equations must be regular. The coefficient matrix is made regular by setting five reference points for calibration and limiting the arrangement.

The sensor heads are arranged as follows so as to satisfy the above conditions. That is, line segments op-p1, op-p2, 0-p3, op-p4 connecting the point o and each point.
The points o and p1 and p1, p
2, p3, p4, p5 (sensor head 2 and reference point) are arranged. Similarly, for at least one sensor head (the other sensor head 1) other than the above-mentioned sensor head among the plurality of sensor heads, the reference is made such that all the line segments connecting the principal point of the light receiving lens and the reference point do not coincide with each other. Position the points and the sensor head.

(Eighth Embodiment) An eighth embodiment is an embodiment in which the calibration mode and the coordinate input mode are switched. In other words, this embodiment is configured such that the user can switch the mode arbitrarily, such as when the position of the mapping means shifts during use of the coordinate input device or immediately after transportation, and perform calibration by himself.

FIG. 8 shows the structure of the eighth embodiment. The configuration of this example is applied to the optical coordinate input device described in the first, second, third, and fourth embodiments. The difference from the first embodiment is that switching means 12 to 17 for switching the operation state are provided. These switching units 12 to 17 all operate in conjunction with each other in accordance with an instruction from the operation state instruction unit 18. When the switching means 12 to 17 are in the illustrated state,
It is in the calibration operation mode. Switching means 12-
When the number 17 is switched, a coordinate input operation mode is set. As the operation state instructing means 18, for example, a method of instructing the switching means from a user or the like is adopted.

FIG. 9 is a processing flowchart of the eighth embodiment. Start 1 indicates the starting point of each calibration operation mode of the two sensor heads. Start 2
Indicates the starting point of the normal coordinate input operation mode.

The start indicates the starting point of the processing. It is assumed that the normal coordinate input operation mode is executed after the coefficient writing operation to the second storage units 7 and 8 is performed at least once in the calibration operation mode.

After the processing is started at the start, it is determined whether the operation mode is the calibration operation mode or the normal coordinate input mode (step 301). This is performed, for example, by the user determining the state of the switching units 12 to 17. Alternatively, a method of making a determination by referring to flags corresponding to the states of the switching units 12 to 17 can be adopted.

If it is determined that the operation mode is the calibration operation mode, the operation proceeds to start 1 and the calibration operation is performed (steps 302 to 306). Otherwise, the operation proceeds to start 2 and normal coordinate input operation is performed. (Steps 307 to 310). When one operation of each operation is completed, the operation returns to the start again, determines whether or not the operation is in the calibration mode, and performs the same operation.

FIG. 8 shows an example in which two sensor heads are installed as shown in FIG. The coordinates of the reference point for calibration are known coordinates on the coordinate input surface (x ₁ , y ₁ ), (x ₂ , y ₂ ). . . (X _5, y ₅₎
And For example, in a configuration example in which the coordinate input device of the present invention is installed on an electronic display or a screen surface that projects a projector, these reference points are displayed as predetermined marks on the display or on the screen surface during the calibration operation. You. In a conventional whiteboard, blackboard, or the like, a method of setting a reference chart or the like on which predetermined coordinates are printed on the surface, or engraving a mark or the like on the board in advance may be considered.

In the calibration operation mode, a pointing object is inserted at each reference point. For example, when the pointing object is inserted at the reference point (x ₁ , y ₁ ), the mapping position of the pointing object on the sensor head 1 (FIG. 15A, FIG. 18A, FIG.
0A, the corresponding information in FIG. 24A) and u _11. Similarly the mapping position of the pointing object on the sensor head 2 and u _12. The first subscript of u corresponds to the reference point subscript, and the second subscript corresponds to the sensor head number. u may be any information as long as it corresponds to the mapping position of the pointing object shown in FIGS. 15A, 18A, 20A, and 24A.

For example, when the light receiving element 50 is a CCD in FIG. 15 of the first embodiment, u can use a pixel suffix of the CCD corresponding to the light blocking position. u is the timing of the signal for scanning the CCD, that is, CC
It may be the time from the start of scanning D to the position of the dark spot. In the case of the second embodiment, the time Δt or the time t1 corresponding to the portion A shown in FIG.
Let u be the value obtained by converting ωΔt and ftan ωt1. Here, f is the focal length of the light receiving lens, and ω is the rotational angular velocity of the polygon mirror. These may be given an arbitrary coefficient or offset, and any parameter convenient for the design of the apparatus can be arbitrarily used.

Reference points (x ₁ , y ₁ ), (x ₂ , y ₂ ). . .
(X ₅ , y ₅ ), when the object is inserted, the mapping position information (u ₁₁ , u ₂₁ ,..., U ₅₁ ) of the pointing object in the sensor head 1 and the sensor head 2 and (u ₁₂ , u ₂₂ ,..., u ₅₂ ) and the coordinates of the reference point are stored in the first storage units 3 and 4, respectively (step 30).
4).

Reference point coordinates stored in first storage units 3 and 4
And the mapping position information of the pointing object are calculated by coefficient calculating means 5 and 6.
And read the coefficient for each sensor head.
(C₁₁, C _{twenty one},. . . , C₅₁) And (c)₁₂,
c_{twenty two},. . . , C₅₂) Is calculated (step 305).
2 are stored in the storage units 7 and 8 (step 306).

Subsequently, an operation mode for inputting coordinates is entered. The pointing object inserted into the coordinate input surface causes a mapping of the pointing object in each of the sensor heads 1 and 2. The sensor heads 1 and ₂ detect information u ₁ and u ₂ corresponding to the position of the pointing object (step 307).

Further, the above-described calibration operation
In the mode, the coefficient (c) stored in the second storage units 7 and 8
₁₁, C_{twenty one},. . . , C₅₁) And (c)₁₂,
c_{twenty two},. . . , C ₅₂) Is read (step 30)
8), the coordinate calculator 9 calculates u₁, U_TwoAnd (c₁₁,
c _{twenty one},. . . , C₅₁) And (c)₁₂, C_{twenty two},. . . , C
₅₂) Is calculated in the same manner as in each of the above-described embodiments.
(Step 309), the coordinates (x,
y) is output (step 310).

The present invention can also be realized by software. In the system configuration shown in FIG. 12, the CPU calculates a coefficient by executing the processing steps and processing functions of the above-described embodiments at the time of the calibration operation, and performs the processing steps and processing functions of the above-described embodiments at the time of inputting the coordinates. Is executed, the drawing data is generated from the input coordinate data, and characters and the like are displayed on the display device.

The program for executing the above processing is C
A program recorded on a recording medium such as a D-ROM is read from a CD-ROM device,
It is executed by installing it in the system, and realizes the processing functions described in the above embodiments. In addition, the above-described program is provided by being downloaded from a server or the like via a communication device or a network in addition to a medium.

[0175]

As described above, according to the present invention, the following effects can be obtained. (1) It is not necessary to know the absolute position of the mapping means, so that the degree of freedom in installation can be greatly increased, and a highly reliable coordinate input device can be constructed. (2) Calibration operation can be performed by simple matrix calculation or solution of simultaneous equations. (3) When the present invention is applied to the retro-light projection method or the polygon mirror method, the degree of freedom of the mounting position of the light receiving and emitting means on the coordinate input surface can be increased, and the mounting position of the light receiving and emitting means on the coordinate input surface is unknown. Even in this case, the coordinates on the coordinate input surface can be correctly input by a simple calibration operation before use. (4) When applied to the imaging method, the degree of freedom of the mounting position of the image input means on the coordinate input surface can be increased, and even if the mounting position of the light receiving and emitting means on the coordinate input surface is unknown, before use. With the simple calibration operation, the coordinates on the coordinate input surface can be correctly input. (5) When applied to a pen with a reflector, the degree of freedom of the mounting position of the light receiving means or the light emitting means on the coordinate input surface can be increased, and the mounting position of the light receiving means or the light emitting means on the coordinate input surface is unknown. Even in this case, the coordinates on the coordinate input surface can be correctly input by a simple calibration operation before use. (6) When the present invention is applied to the retroreflective projection system or the polygon mirror system, the degree of freedom of the mounting position of the light receiving and emitting means on the coordinate input surface can be increased, and the mounting position of the light receiving and emitting means on the coordinate input surface, that is, as described above. Even if the parameters are unknown, the coordinates on the coordinate input surface can be correctly input by a simple calibration operation before use, and the calibration operation is performed by simple matrix calculation or solving simultaneous equations Further, the information corresponding to the position of the light blocked by the light blocking unit inserted at the predetermined coordinates for the calibration is scanned with the geometric position on the light receiving element or the light receiving element. It can be calculated with any signal such as a timing signal, and the position of the blocked light can be estimated by the blocking means. Process of converting such to degrees can also be omitted, the efficiency of significant operations, improving design flexibility of the device, it is possible to improve the coordinate calculation precision. (7) When applied to the imaging method, the degree of freedom of the mounting position of the image input means on the coordinate input surface can be increased, and even when the mounting position of the image input means on the coordinate input surface, that is, the aforementioned parameter is unknown. In addition to being able to correctly input the coordinates on the coordinate input surface by a simple calibration operation before use, it is possible to execute the calibration operation by a simple matrix calculation or solving a simultaneous equation, The information on the image plane input by the image input means corresponding to the instruction means inserted at the predetermined coordinates for calibration is used as a geometrical position on the light receiving element, or a timing signal for scanning the light receiving element. The position of the information on the image plane of the image input means can be calculated by an arbitrary signal, and the angle of the expected value of the indicating means can be calculated. Process for conversion etc. can also be omitted, the efficiency of significant operations, improving design flexibility of the device,
The accuracy of coordinate calculation can be improved. (8) When the present invention is applied to a pen with a reflecting plate, the degree of freedom of the mounting position of the light receiving means or the light emitting means on the coordinate input surface can be increased. Even if the parameters are unknown, the coordinates on the coordinate input surface can be correctly input by a simple calibration operation before use, and the calibration operation is performed by simple matrix calculation or solving simultaneous equations Further, information corresponding to the position of the light reflected by the reflecting means inserted at the predetermined coordinates for the calibration is used as the geometrical position on the light receiving element, or the timing of scanning the light receiving element. The signal can be calculated using any signal, such as a signal, and the position of the reflected light is estimated by the reflection means. Process of converting such an angle can also be omitted, the efficiency of significant operations, improving design flexibility of the device, it is possible to improve the coordinate calculation precision. (9) Since information corresponding to the image plane position of the light receiving unit or the image input unit of the instruction unit, that is, the physical position (dip / peak / image position on the image plane) on the light receiving element is used, the conversion table is used. In addition, it is possible to omit a process of creating a conversion formula or a conversion formula, and to eliminate an error factor generated in this process. Furthermore, if it is a signal corresponding to the position of the image of the pointing means on the light receiving element, in addition to its physical position, it is also possible to calculate other physical quantities, such as a timing signal for electrical scanning of the light receiving element, The degree of freedom in design can be greatly improved. (10) Since information corresponding to the image plane position of the light receiving means of the indicating means, that is, the physical position on the light receiving element (the distribution shape portion in the time change of the light intensity of the image plane) is used,
It is possible to omit a process of creating a conversion table and a conversion formula, and it is possible to eliminate an error factor generated in this process. Furthermore, if it is a signal corresponding to the position of the image of the pointing means on the light receiving element, in addition to its physical position, it is also possible to calculate other physical quantities, such as a timing signal for electrical scanning of the light receiving element, The degree of freedom in design can be greatly improved. (11) By limiting the number of calibration points and the method of arranging the reference coordinates, the coefficient matrix of the simultaneous equations can always be regular. (12) Since the calibration mode and the coordinate input mode are provided, the user can switch the mode arbitrarily, such as when the position of the mapping means shifts during use or immediately after transportation, and perform calibration by himself. it can.

[Brief description of the drawings]

FIG. 1 is a diagram showing a configuration of Embodiments 1 to 3 of the present invention.

FIG. 2 is a processing flowchart according to Embodiments 1 to 3 of the present invention.

FIG. 3 is a diagram illustrating the concept of a camera system.

FIG. 4 is a diagram illustrating a configuration of a fourth embodiment of the present invention.

FIG. 5 is a processing flowchart according to Embodiments 4 and 5 of the present invention.

FIG. 6 is a diagram showing a configuration of a fifth embodiment of the present invention.

FIG. 7 is a diagram illustrating the arrangement of a reference point and a sensor head.

FIG. 8 is a diagram illustrating a configuration of an eighth embodiment of the present invention.

FIG. 9 is a processing flowchart according to an eighth embodiment of the present invention.

FIG. 10 is an external view of an electronic blackboard system.

FIG. 11 is a diagram illustrating a configuration of an electronic blackboard system.

FIG. 12 is a diagram illustrating a configuration in a computer that controls the electronic blackboard system.

FIG. 13 is a diagram illustrating an optical coordinate input device according to a first embodiment to which the present invention is applied.

FIG. 14 is a diagram showing an internal configuration of the light receiving / emitting means of FIG.

FIG. 15 is a diagram illustrating an operation when the pointing object is inserted and the beam is cut off.

FIG. 16 is a diagram illustrating a method of calculating a coordinate position based on the principle of triangulation.

FIG. 17 is a diagram illustrating an optical coordinate input device according to a second embodiment to which the present invention is applied.

FIG. 18 is a diagram illustrating an example of an output signal of a light receiving element.

FIG. 19 is a diagram showing an optical coordinate input device according to a third embodiment to which the present invention is applied.

FIG. 20 is a diagram illustrating a relationship between a signal of an imaging camera and a pointing object.

FIG. 21 is a diagram showing an optical coordinate input device according to a fourth embodiment to which the present invention is applied.

FIG. 22 is a diagram illustrating a configuration example of a retroreflective pointing object.

FIG. 23 is a diagram illustrating an example of an output signal when the light receiving / emitting unit has the configuration illustrated in FIG. 14;

FIG. 24 is a diagram showing an example of an output signal when the light receiving / emitting means has the configuration shown in FIG. 17;

FIG. 25 is a diagram showing an example in which a sensor head is arranged near a coordinate input area.

[Explanation of symbols]

 1, 2 sensor head 3, 4 first storage section 5, 6 coefficient calculation section 7, 8 second storage section 9 coordinate calculation section

Claims (22)

[Claims] 1. A plurality of mapping means for mapping a point on a two-dimensional or three-dimensional first coordinate system to a point on a two-dimensional or one-dimensional second coordinate system different from the first coordinate system. And a position where a plurality of predetermined coordinates on the first coordinate system are mapped on the second coordinate system by the plurality of mapping means, and a plurality of predetermined coordinates on the first coordinate system. First storage means for storing in association with a plurality of predetermined coordinates on the first coordinate system stored in the first storage means and a position mapped on the second coordinate system; A coefficient for calculating a coefficient of a relational expression describing a relationship between an arbitrary coordinate on the first coordinate system and a position mapped on the second coordinate system by the mapping means corresponding to the arbitrary coordinate. Calculating means, second storing means for storing the calculated coefficient, and an arbitrary value on the first coordinate system. Using the position mapped on the second coordinate system corresponding to the coordinates, the coefficient stored in the second storage means, and the relational expression, an arbitrary coordinate on the first coordinate system A coordinate input device comprising: 2. An n-th mapping means of the plurality of mapping means, wherein an arbitrary coordinate on the two-dimensional first coordinate system is (x, y), and the one-dimensional second coordinate is Assuming that the position mapped on the system is u and c _{1n to} c _5n are coefficients in the n-th mapping means, the relational expression describing the relation between the arbitrary coordinate (x, y) and the position u is , [Equation 1] Where a plurality of predetermined coordinates on the two-dimensional first coordinate system are m (x ₁ , y ₁ ) to (x _m , y _m ), and the m coordinates (x ₁ , y ₁ ) When the positions mapped on the second coordinate system by the n-th mapping means corresponding to (x _m , y _m ) on the second coordinate system are u _{1n to} u _mn , the coefficient calculation means calculates the coefficient c _1n To c _5n , The number of the mapping means is defined as _N, and the positions mapped on the second coordinate system by the N mapping means corresponding to the arbitrary coordinates (x, y) are defined as u _{1 to} u _N. At this time, the coordinate calculating means calculates an arbitrary coordinate (x, y) on the two-dimensional first coordinate system by: The coordinate input device according to claim 1, wherein the coordinate is calculated according to 3. The coordinate input device according to claim 1, wherein said mapping means comprises a plurality of light emitting means and a plurality of light receiving means in a predetermined coordinate input device. 4. The coordinate input device according to claim 1, wherein said mapping means comprises a plurality of image input means in a predetermined coordinate input device. 5. The coordinate input device, comprising: a plurality of light emitting units, a plurality of light receiving units, and a reflecting unit configured to reflect light emitted from the light emitting units in a direction substantially the same as the direction of the light emitting units. The light receiving unit is arranged at a position where the light reflected by the reflecting unit can be received, and the light blocking unit is inserted when the light blocking unit is inserted into the light emitting and receiving light paths. The coordinate input device according to claim 3, wherein the calculated two-dimensional coordinates are input. 6. A predetermined coordinate input device, comprising: a plurality of light emitting means; a plurality of light receiving means provided in close proximity to the light emitting means; and a light emitted from the light emitting means substantially corresponding to the light emitting means. An indicator having a retroreflecting portion for reflecting the light at the same position and leading to the light-receiving means, and reflecting the emitted light by inserting the indicator into an optical path of the light emission and the light reception; 4. The coordinate input device according to claim 3, wherein the input device calculates and inputs the two-dimensional coordinates into which the is inserted. 7. The predetermined coordinate input device comprises a plurality of image input means for photographing and inputting an instruction means inserted into a coordinate input area, and calculating the two-dimensional coordinates at which the instruction means is inserted. The coordinate input device according to claim 4, wherein the input is performed. 8. At least two of said plurality of mapping means
2. A method according to claim 1, wherein the plurality of predetermined coordinates are coordinates of at least five points where a straight line connecting the approximate center of the two mapping means and the predetermined coordinates does not coincide with each other. 2. The coordinate input device according to 2. 9. A method according to claim 1, wherein said instruction information inserted into said plurality of predetermined coordinates associates mapping information of said instruction means formed on said plurality of mapping means with said plurality of predetermined coordinates. Based on the operation to be stored in the storage means and the plurality of predetermined coordinates stored in the first storage means and the mapping information of the pointing means, the coordinates when the pointing means is inserted at any coordinates. And an operation of calculating a coefficient of a relational expression describing a relationship between the mapping information corresponding to the arbitrary coordinates and the mapping information mapped by the plurality of mapping means, and storing the calculated coefficient in the second storage means. A first operation mode for executing an operation, mapping information to be mapped by the mapping means corresponding to the arbitrary coordinates when the instruction means is inserted at arbitrary coordinates, and Said stored coefficients; 2. The coordinate input device according to claim 1, further comprising a unit that exclusively switches between a second operation mode in which the pointing unit calculates an inserted arbitrary coordinate using the relational expression. . 10. The image input device according to claim 9, wherein the first operation mode is a mode executed at the time of calibration, and the second mode is a mode executed at the time of inputting coordinates. apparatus. 11. A plurality of light emitting means and a plurality of light receiving means,
Reflecting means for reflecting light emitted from the light emitting means in a direction substantially the same as the direction of the light emitting means, and arranging the light receiving means at a position where the light reflected by the reflecting means can be received. 6. The coordinate input device according to claim 5, wherein, when the light path is interrupted by inserting the light shielding means into the light path, the light shielding means calculates and inputs the inserted two-dimensional coordinates. A first storage unit configured to store a plurality of predetermined coordinates into which the light blocking unit is inserted and optical position information in the plurality of light receiving units corresponding to the plurality of predetermined coordinates in association with each other; Based on the predetermined coordinates and the optical position information stored in the storage means, the coordinates when the light blocking means is inserted at arbitrary coordinates, and the plurality of coordinates corresponding to the arbitrary coordinates. In the light receiving means A coefficient calculating unit for calculating a coefficient of a relational expression describing a relationship with optical position information, a second storage unit for storing the calculated coefficient, and the light blocking unit inserted at arbitrary coordinates. When, optical position information in the plurality of light receiving means corresponding to the arbitrary coordinates,
A coordinate input device comprising: a coefficient calculating unit that calculates an arbitrary coordinate at which the light blocking unit is inserted, using the coefficient stored in the second storage unit and the relational expression. . 12. A plurality of light emitting means, a plurality of light receiving means provided adjacent to and corresponding to the light emitting means, and light emitted from the light emitting means is reflected at substantially the same position as the light emitting means. Indicating means having a retroreflective portion leading to the means, and reflecting the emitted light by inserting the indicating means in the light path of the light emission and light reception, and converting the two-dimensional coordinates into which the indicating means is inserted. 7. The coordinate input device according to claim 6, wherein said input is performed by calculating a plurality of predetermined coordinates into which said indicating means is inserted, and positions of reflected light in said plurality of light receiving means corresponding to said plurality of predetermined coordinates. First storage means for storing information in association with the information;
The coordinates when the indicating means is inserted at arbitrary coordinates, and the plurality of light receptions corresponding to the arbitrary coordinates, based on the predetermined coordinates and the position information of the reflected light stored in the storage means. A coefficient calculating means for calculating a coefficient of a relational expression describing a relation between the reflected light and the position information in the means, a second storage means for storing the calculated coefficient, and the indicating means inserted at arbitrary coordinates. When the pointing means is inserted using the positional information of the reflected light at the plurality of light receiving means corresponding to the arbitrary coordinates, the coefficient stored in the second storage means, and the relational expression. A coordinate calculating means for calculating arbitrary coordinates. 13. The coordinates according to claim 7, comprising a plurality of image input means for photographing and inputting the pointing means inserted into the coordinate input area, wherein said pointing means calculates and inputs the inserted two-dimensional coordinates. An input device, wherein a plurality of predetermined coordinates into which the indicating means is inserted and image position information of the indicating means in the plurality of image input means corresponding to the plurality of predetermined coordinates are stored in association with each other. Based on the predetermined coordinates stored in the first storage and the image position information of the pointing means, the coordinates when the pointing means is inserted at arbitrary coordinates, Coefficient calculating means for calculating a coefficient of a relational expression describing a relationship between the plurality of image input means and the image position information of the indicating means corresponding to the coordinates of the plurality of image input means, and a second storage means for storing the calculated coefficient And the pointer When a column is inserted at any coordinate,
The pointing means is inserted using the image position information of the pointing means in the plurality of image input means corresponding to the arbitrary coordinates, the coefficient stored in the second storage means, and the relational expression. A coordinate calculating means for calculating arbitrary coordinates. 14. The optical position information according to claim 11, wherein a position of a portion having a predetermined distribution shape in a light intensity distribution on an image plane of said light receiving means is used.
The image input device according to the above. 15. The method according to claim 12, wherein a position of a portion having a predetermined distribution shape in a light intensity distribution on an image plane of the light receiving means is used as the position information of the reflected light.
Coordinate input device as described. 16. The coordinate input device according to claim 13, wherein a position of a portion having a predetermined distribution shape in a light intensity distribution on an image plane of said image input means is used as said image position information. 17. The optical position information according to claim 11, wherein a portion having a predetermined distribution shape is used in a temporal change of the light intensity in the light receiving means.
The image input device according to the above. 18. The method according to claim 12, wherein a portion having a predetermined distribution shape is used as the positional information of the reflected light in the time change of the light intensity in the light receiving means.
Coordinate input device as described. 19. The coordinate input device according to claim 13, wherein a portion having a predetermined distribution shape is used as the image position information in the time change of the light intensity in the image input means. 20. A plurality of mapping processes for mapping a point on a two-dimensional or three-dimensional first coordinate system to a point on a two-dimensional or one-dimensional second coordinate system different from the first coordinate system. A program for causing a computer to execute a function of estimating a point on the first coordinate system from information on a second coordinate system mapped by a function, the program comprising a plurality of functions on the first coordinate system. The predetermined coordinates are converted into the second coordinates by the plurality of mapping processing functions.
A first storage processing function for storing the coordinates mapped on the coordinate system and the plurality of predetermined coordinates on the first coordinate system, and the first storage processing function storing the first storage processing function. Based on a plurality of predetermined coordinates on a first coordinate system and coordinates mapped on the second coordinate system, the coordinates correspond to arbitrary coordinates on the first coordinate system and the arbitrary coordinates. A coefficient calculation processing function for calculating a coefficient of a relational expression describing a relation with the coordinates mapped on the second coordinate system by the mapping processing function;
A second storage processing function for storing the calculated coefficient;
An arbitrary coordinate mapped onto the second coordinate system by the plurality of mapping processing functions corresponding to an arbitrary coordinate on the first coordinate system; and the coefficient stored by the second storage processing function And a program for causing a computer to execute a coordinate calculation processing function of calculating arbitrary coordinates on the first coordinate system using the relational expression. 21. An n-th mapping processing function among the plurality of mapping processing functions, wherein arbitrary coordinates on the two-dimensional first coordinate system are (x, y), and the one-dimensional second Where u is the position mapped on the coordinate system and c _{1n to} c _5n are coefficients in the n-th mapping processing function, the relationship between the arbitrary coordinate (x, y) and the position u is described. The relational expression is: Where a plurality of predetermined coordinates on the two-dimensional first coordinate system are m (x ₁ , y ₁ ) to (x _m , y _m ), and the m coordinates (x ₁ , y ₁ ) When the positions mapped on the second coordinate system by the n-th mapping processing function corresponding to (x _m , y _m ) are u _{1n to} u _mn , the coefficient calculation processing function c _{1n to} c _5n are given by: And the number of the mapping processing functions is N, and the positions mapped on the second coordinate system by the N mapping processing functions corresponding to the arbitrary coordinates (x, y) are u _{1 to} u _N. , The coordinate calculation processing function performs the two-dimensional first
An arbitrary coordinate (x, y) on the coordinate system of The program according to claim 20, wherein the program is calculated according to: 22. A computer-readable recording medium on which the program according to claim 20 is recorded.