JP2000322201A - Coordinate input device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a coordinate input device where the variance of detection precision in a coordinate input face is eliminated and the error of the detection angle hardly has an influence upon the detection precision of coordinates. SOLUTION: The coordinate input device is provided with a coordinate input face 50 and plural electronic cameras 4a and 4b, which detect a finger or the like designating a point on the coordinate input face and input the position of the designated point, and detects angles formed between lines passing the finger and electronic cameras 4a and 4b and the line passing electronic cameras 4a and 4b with respect to at least two electronic cameras and calculates two-dimensional coordinates of the point designated by the finger on the basis of detected angles and a distance W between electronic cameras used for angle detection. In this coordinate input device, a non-input area G where electronic cameras do not accept the point input with a finger is provided between electronic cameras 4a and 4b used for angle detection and the coordinate input face 50.

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 coordinate input device for inputting coordinates of a position designated by a pen or a finger into a predetermined area.

[0002]

2. Description of the Related Art At present, there is a so-called touch panel type coordinate input device in which an operator specifies a position on a surface by touching a predetermined surface with a finger or a pen, and detects and inputs coordinates of the position. is there. Such a coordinate input device is used for an electronic blackboard or a personal computer (PC), and is used for inputting coordinates on a panel or a display surface.
It is configured integrally with a detection area (hereinafter simply referred to as a coordinate input surface).

A conventional coordinate input device detects an electrostatic change caused by touching a coordinate input surface with a pen or an electric change caused by electromagnetic induction, or generates a surface acoustic wave on a surface of the coordinate input surface. There is known an ultrasonic type (Japanese Patent Laid-Open No. 61-239322) which transmits an ultrasonic wave and detects the attenuation caused by touching a coordinate input surface. Also, the applicant of the present invention has proposed an optical coordinate input device using a triangulation method (Japanese Patent Application No. 10-127).
No. 035) has been proposed. According to the optical coordinate input device, a coordinate input device having a relatively simple configuration can be realized.

[0004]

However, among the above-described conventional coordinate input devices, those having a configuration for detecting an electrical change require the provision of an electrical switch function on the coordinate input surface, and therefore, are not manufactured. The cost becomes high. Also,
There is a problem that the operability of the pen is impaired because there is a cable for connecting the pen with the apparatus main body in which the coordinate input device is incorporated. Further, the ultrasonic type is configured on the premise that a coordinate input surface is touched with a finger. For this reason, when you touch the coordinate input surface with an elastic pen or the like, the coordinates can be detected stably at the time of touch,
When trying to input a line by moving the pen, the line may be cut off halfway without obtaining sufficient contact with the coordinate input surface. In such a case, if the pen is further pressed against the coordinate input surface, the pen is bent and a stress is generated.
For this reason, when moving the pen in which the force pressing the pen against the coordinate input surface is weakened, the contact between the pen and the coordinate input device is weakened, and it is impossible to prevent the line from being broken.

[0005] Further, the coordinate input device as disclosed in Japanese Patent Application No. 10-127035 can solve the problems of the coordinate input device of the above-mentioned method, but presently has the following problems. That is, in a coordinate input device that detects coordinates input based on a triangulation method, it is known that the detection accuracy of the coordinates varies in the coordinate input plane on this principle. For example, consider a case where the coordinate input surface is a quadrangle, and a sensor for detecting a pen or the like that designates a point on the coordinate input surface is provided at each end of one side.

In a coordinate input device provided with such a sensor, the position of the detected pen is obtained from the angle with itself. For this reason, if an error occurs in the angle detected by the sensor, the error has a greater effect when detecting the coordinates of a point near the side provided with the sensor than when calculating the coordinates of a distant point. Also, when detecting the coordinates of a point very close to the side provided with the sensor, the calculation result based on the triangulation method may diverge and the coordinates may not be detected. Therefore, in a coordinate input device using the triangulation method, high accuracy is required for a mounting position and an angle of a sensor, and high stability is required for its detection capability.

SUMMARY OF THE INVENTION The present invention has been made in view of the above points, and eliminates variations in detection accuracy in a coordinate input plane. In addition, a coordinate input apparatus in which a detection angle error hardly affects the coordinate detection accuracy. The purpose is to provide.

[0008]

The above objects can be attained by the following means. That is, according to the first aspect of the present invention, a plurality of designations for detecting a planar coordinate input / detection area and a designated member that designates a point on the coordinate input / detection area and inputting the position of the designated point are provided. An angle detecting means for detecting, for at least two designated point input means, an angle formed by a point input means, a straight line passing through the designated point input means and the designated member, and a straight line passing through the designated point input means; Coordinate calculating means for calculating two-dimensional coordinates of a point designated by the designated member based on the angle detected by the angle detection and the distance between designated point input means used for angle detection. A non-input area is provided between the designated point input means and the coordinate input / detection area used in the above, where the designated point input means does not accept point input by the designated member.

With this configuration, it is possible to avoid calculating the coordinates of a point input to a part having a particularly low detection accuracy in the coordinate input / detection area.

According to a second aspect of the present invention, the non-input area is a predetermined distance represented by a shortest distance between a boundary between the coordinate input / detection area and a straight line passing through designated point input means used for angle detection. And the predetermined width is at least 0.06 times the distance between the designated point input means used for angle detection.

With this configuration, it is possible to set the optimum width of the non-detection area regardless of the mounting position of the designated point input means.

According to a third aspect of the present invention, the non-detection area is provided on the same plane as the coordinate input / detection area, and a signal for detecting a designated member is provided in parallel with the non-input area.
And a detection signal deflecting means for deflecting the light so as to face the coordinate input means.

With this configuration, the non-detection area does not need to be provided in the coordinate input / detection area, and the coordinate input / detection area is not required.
The detection area can be made wider.

According to a fourth aspect of the present invention, there is provided a planar coordinate input / detection area, a plurality of light emitting means for irradiating substantially the entire area of the coordinate input / detection area, and light emitted from the light emitting means. It has a reflecting member that reflects toward the light emitting means, and a plurality of light receiving means provided at positions where the light reflected by the reflecting member can be received, and on the coordinate input / detection area, light emitted by the light emitting means A coordinate input device for inputting, as coordinates, a position of a light shielding member that prevents light from being received by a light receiving unit, and a straight line passing through the light emitting unit and the light shielding member, and an angle formed by a straight line passing through the light emitting unit, at least. Two-dimensional coordinates indicating the position of the light shielding member are determined based on the angle detecting means for detecting each of the two light emitting means, the angle detected by the angle detecting means, and the distance between the light emitting means used for angle detection. Calculation And a non-input area that does not accept a coordinate input by the light shielding member is provided between the light emitting means used for angle detection and the coordinate input / detection area. It is.

With this configuration, a point input to a part with a particularly low detection accuracy in a coordinate input / detection area of a coordinate input device for detecting a point input by shielding emitted light. For, the calculation of the coordinates can be avoided.

According to a fifth aspect of the present invention, the non-input area has a predetermined width represented by a shortest distance between a boundary between the coordinate input / detection area and a straight line passing through the light emitting means used for angle detection. And the predetermined width is at least 0.06 times the distance between the light emitting means used for angle detection.

With this configuration, the optimum width of the non-detection area can be set regardless of the mounting position of the light emitting means.

According to a sixth aspect of the present invention, a non-detection area is provided on the same plane as the coordinate input / detection area, and the optical axis of light emitted from the light emitting means is parallel to the coordinate input / detection area. An optical axis deflecting means for deflecting the light is further provided.

With this configuration, in the coordinate input device for detecting a point input by blocking emitted light, a non-detection area does not have to be provided in the coordinate input / detection area. The detection area can be made wider.

[0020]

DESCRIPTION OF THE PREFERRED EMBODIMENTS In the present specification, embodiments 1 to 4 will be described.
Prior to the description of the image input apparatus described above, first, a description will be given of a variation in coordinate input accuracy in a coordinate input plane by a triangulation method. FIG. 1 is a diagram illustrating a method of calculating coordinates of an input point by a triangulation method. In FIG. 1, it is assumed that the coordinates of the point P (x, y) input on the rectangular coordinate input surface 5 are calculated. Points A and B shown at the upper end of the coordinate input surface 5 are reference points for coordinate calculation, and the length W indicates the distance between the points A and B. Furthermore, θ in the figure
_L and θ _R are the angle between the straight line AB and the straight line AP, the straight line AB
And the straight line BP. In the following description, it is assumed that two sensors for detecting θ _L and θ _R are provided on the coordinate input surface 5 and the centers of the sensors are at points A and B, respectively.

The point P (x, y) represented by the xy coordinate having the point A as the origin is represented by the following equations (1) and (2) from the above conditions. x = f ([theta] _L , [theta] _R ) (1) y = g ([theta] _L , [theta] _R ) (2) where f ([theta] _L , [theta] _R ) = W * tan [theta] _R / (tan [theta] _L + tan [theta] _R ) .. (3) g (θ _L , θ _R ) = W · tan θ _L · tan θ _R / (tan θ _L + tan θ _R ) (4)

Here, if θ _L changes by θ _eL and θ _R changes by θ _eR , the calculated coordinate changes dx and dy are:
It is represented by the following equation. dx (θ _eL , θ _eR , θ _L , θ _R ) = f (θ _L + θ _eL , θ _R + θ _eR ) −f (θ _L , θ _R ) (5) dy (θ _eL , θ _eR , θ _L) , Θ _R ) = g (θ _L + θ _eL , θ _R + θ _eR ) −g (θ _L , θ _R ) (6)

Therefore, the coordinate variation distance D (indicated by the difference between the distance between point A and (x, y) and the distance between point A and (x + dx, y + dy)) due to the variations dx and dy is D (θ _eL , θ _eR , θ _L , θ _R ) = {dx ² (θ _eL , θ _eR , θ _L , θ _R ) + dy ² (θ _eL , θ _eR , θ _L , θ _R )} ^-1/2 … ( 7) Fluctuations distance D as described above, theta _L, the average fluctuation amount D _ave when theta _R varies in a range of - [theta] _e through? _E, respectively, are expressed as follows.

(Equation 1) The above equation (8) is an evaluation introduced to show that even when the fluctuation of the sensor for detecting the angle is the same, the influence on the average fluctuation amount due to the nonlinearity of the arithmetic expression of the triangulation method differs depending on the position of the coordinate. Function.

Here, for example, 60 inches (diagonal length),
In the center of the screen with an aspect ratio of 16: 9, X with an aspect ratio of 4: 3
GA (Extended Graphics Array) compatible (1024 x 7
When displaying a screen of (68 pixels), the angle detection accuracy of the sensor required to identify this one pixel will be obtained. Under the above conditions, the pitch of one pixel is 0.97 mm.
For example, at a point 60 inches farthest from the sensor, 2
In order to anticipate one point, that is, to reliably identify the difference of one pixel, the fluctuation of the angle detected by the sensor is reduced by about 0.03.
It is estimated that it is necessary to keep it below deg.

However, the value of about 0.03 deg is an allowable fluctuation value of the detection angle obtained for the coordinates at a distance of 60 inches from the sensor. Next, the value of 0.03 deg is substituted into Expression (8), and the amount of coordinate fluctuation when the detection angle of the sensor fluctuates by 0.03 deg is shown in FIG. FIG. 2 is a diagram showing the coordinate fluctuation amount by contour lines, and a blank portion in the upper part of FIG. 2 is omitted because the contour lines are dense and cannot be described. According to FIG. 2, when the detection angle of the sensor fluctuates by 0.03 deg, the coordinate fluctuation distance D in the portion D in the coordinate input surface 5 is 0.4 mm, and
It can be seen that it is small enough to identify a pixel. However, the coordinate variation distance D of the portion C closer to the sensor position (indicated by points A and B) is 0.8 mm or more.

FIG. 3 is a sectional view of FIG. 2 cut by a straight line E having the origin at the point O shown in FIG. 2. The vertical axis represents the coordinate variation distance D, and the horizontal axis represents the y coordinate of this coordinate. (Distance from the origin O in the y direction). This unit is mm. According to FIG. 3, the coordinate variation distance D is y
The smaller the value of the coordinate, that is, the smaller the distance between the detected coordinate and the straight line AB, the larger the value. When the distance is 80 mm, it can be seen that the coordinate variation distance D is 1 mm, which is almost equal to the pixel pitch. Therefore, under the above conditions, the detection angle of the sensor is 0.03 d
Even when the fluctuates eg, the straight line AB on the coordinate input surface 5
With respect to the coordinates input to an area having a distance of 80 mm or more with respect to the pixel pitch, the fluctuation amount is equal to or less than the pixel pitch, and there is substantially no problem.

Hereinafter, the first, second, third, and fourth embodiments of the present invention, which are configured in consideration of the above-described variation in the coordinate input accuracy in the coordinate input plane, will be described. In the first to fourth embodiments, a sensor used for angle detection is provided between a point A and a point B where the center of the sensor is located and a coordinate input surface 5 which is a coordinate input / detection area. Is provided with a non-input area which does not accept the input of the input. First, such a non-input area is schematically shown in FIG. 4 and will be described.

The configuration shown in FIG. 4 is based on a coordinate input surface 5 and an angle detection device provided such that the center is located on a straight line AB that is a distance F away from the upper end of the coordinate input surface 5 indicated by a straight line A'B '. (Not shown). A region between the straight line AB and the straight line A′B ′ and having a length W is a non-input region G. The non-input area G has a predetermined width F
(Distance between the straight line AB and the straight line A′B ′).

The width F is a value determined according to the distance (length W) between the reference points A and B. The value of 80 mm is 60 inches, 16: 9, that is, W is 1330 mm.
Is a value calculated for the coordinate input surface 5. However,
Even when W is different, if the combination of θ _L and θ _R used in the equation (8) is the same, the coordinate variation distance D shows the same behavior as that shown in FIG. Therefore, W1330
A value that takes the same ratio as 80 mm to 80 mm, that is, a value obtained by multiplying W by 0.06 (80/1330) is a non-input area G
When the width F is set, the variation in the detection angle of the sensor is 0.03 deg or less, and the coordinate variation distance D is less than the allowable value over the entire coordinate input surface.

(Embodiment 1) In Embodiment 1, a coordinate input surface which is a planar coordinate input / detection area, and a designation member (in this embodiment, a finger and a finger) for designating a point on the coordinate input surface. Angle detection that detects an angle formed by an input unit having a plurality of electronic cameras for inputting the position of a designated point, a straight line passing through the electronic camera and a finger, and a straight line passing through the electronic camera. Means for calculating two-dimensional coordinates of a point designated by the designated member based on the angle detected by the angle detecting means and the distance between the designated point input means used for angle detection. And a calculation unit. The input unit has a non-input area between the electronic camera used for angle detection and the coordinate input surface, where the electronic camera does not accept input of a point by a finger. In the first and second embodiments, a “line passing through the electronic camera” will be referred to as a line connecting substantially the center points of light condensed on the electronic camera, which corresponds to a line passing through A and B in FIG. Shall point to.

The above configuration will be described below in the order of the input unit and the operation unit. (Input Unit) FIG. 5 is a front view for explaining the input unit, and FIG. 6 is a cross-sectional view taken along line VV ′ (shown in FIG. 5) of FIG. The coordinate input device according to the first embodiment includes two electronic cameras 4a and 4b provided above the coordinate input surface 50 at a distance L, and an electronic camera 4a,
It has a light shielding plate 25 provided on the front surface of the electronic camera 4b, a background plate 7 surrounding three directions except above the coordinate input surface 50, and the support 2 supporting the above configuration. Embodiment 1
Shows an example in which such a coordinate input device is attached to a display Di of a personal computer. For this purpose, a rectangular notch having substantially the same area as the display Di is provided on the surface of the support 2, and the display Di is exposed from the notch 20 (FIG. 8), and the coordinate input device is provided. Is formed on the display Di.

The electronic camera 4a and the electronic camera 4b have a two-dimensional image sensor 15 and an imaging optical lens 6, respectively.
And are provided. The two-dimensional image sensor 15 is a two-dimensional CCD image pickup device formed by arranging a large number of CCDs (Charge Coupled Devices) in a matrix. The two-dimensional image sensor 15 and the imaging optical lens 6 have a distance f. It is arranged in. Such an electronic camera 4a and the electronic camera 4b are configured to be able to image the entire area of the coordinate input surface 50. The electronic camera 4a and the electronic camera 4b are fixed to the support 2 so as to capture light passing through an optical axis coinciding with the surface of the display Di, and the display D is located in the imaging area.
This prevents i from being reflected.

The boundary line 51 between the electronic cameras 4a and 4b and the coordinate input surface 50 is provided at a distance d longer than 0.06 times W which is the distance between the electronic cameras 4a and 4b. This area is a non-input area G. In order to prevent such a non-input area G from receiving an input, by providing a shield such as a cover over the entire non-input area G, the operator can recognize that the non-input area G is the non-input area G. Or if the detected coordinates are located in the non-input area G, it may be possible not to return the coordinate values to the application.

The light shielding plate 25 is a member functioning as an image pickup area limiting means for the electronic cameras 4a and 4b.
It is configured as follows. That is, the light shielding plate 25 is
It is a square plate having a notch 251 long in the center along the y direction. The notch 251 is designed to limit an area that can be imaged by the electronic camera 4a and the electronic camera 4b to within the coordinate input surface 5, and captures noise due to disturbance light and an image outside the coordinate input surface 5. This prevents false detections that occur.

Further, the background plate 7 shown in FIG. 8 is provided at a position where it can be seen in the entire field of view of the electronic cameras 4a and 4b. As shown in the figure, the background plate 7 includes stripes 71a and 71, which are horizontal stripes of dark and light colors serving as reference patterns.
b is drawn on the entire surface, and the stripes 71a, 71
b facilitates a difference image extraction process described later. Such a reference pattern includes a stripe 71
In addition, a light and shade vertical stripe pattern, a color pattern used in chroma key technology, and the like may be used.

(Calculation Unit) FIG. 9 is a block diagram for explaining the calculation unit according to the first embodiment. The arithmetic unit is configured to detect the position of the finger input to the input unit as an angle, and to perform an arithmetic operation for calculating the coordinates. For this purpose, the ROM 11 for storing fixed data (such as a control program) and a rewrite. RAM for storing necessary data
12. Interface for connecting to a personal computer (I
/ F) 9, an EEPROM 16 for executing calculations, an integrator 14, an xyz calculator 18, and a timer 13 used for setting the operation timing of each component. All of the above components are connected to the bus 1 and are totally controlled by the CPU 10. In addition, such a configuration is generally integrally configured as a microcomputer.

The RAM 12 has a coordinate memory 12a. The coordinate memory 12a is a RAM used to temporarily store the calculated coordinates. Also, E
The EPROM 16 is provided with a reference image memory 16a. The reference image is, for example, an image captured when the coordinate input device is activated, and is often an image as shown in FIG. The reference image memory 16a is a memory that stores the reference image for use in processing described below for detecting the position of the finger.

The operation of the input unit and the operation unit described above is
This will be described below with reference to FIGS. Note that FIG.
Represents a point P (x, y, p) on the coordinate input surface 50 shown in FIG.
FIG. 12 is a diagram showing a state in which z) is input, FIG. 12 is a diagram showing an image taken by the electronic camera 4a in FIG. 11, FIG. 13 is a diagram for explaining a series of processes of coordinate input, and FIG. ,
FIG. 12 is an enlarged view of the electronic camera 4a in FIG.

As shown in FIG. 11, a point P on the coordinate input
When (x, y, z) is designated by a finger, the finger is imaged on the two-dimensional image sensors 15 of the electronic cameras 4a and 4b with the background plate 7 as a background as shown in FIG. Thereafter, the same processing is independently performed on the two images formed on the electronic camera 4a and the electronic camera 4b. For this reason, in the present embodiment, the electronic camera 4
a) Regarding the processing independently performed on the image of the electronic camera 4b, only the image captured by the electronic camera 4a will be described, and the description of the image captured by the electronic camera 4b will be omitted.

First, as shown in FIG.
Captures the coordinate input surface 50 prior to the start of the coordinate input. This captured image is stored in the reference image memory 16a as a reference image as shown in FIG. Next, the operator takes an image of a finger specifying a point. The image collected by the two-dimensional image sensor 15 of the electronic camera 4a in this photographing is
It is input to the integrator 14 as a captured image, which is an electric signal output from the electronic camera 4a. At this time, the reference image is also output from the reference image memory 16a and input to the integrator 14. The integrator 14 generates a difference image from the captured image and the reference image.

The difference image is an image obtained by extracting only the difference between the reference image shown in FIG. 10 and the photographed image in FIG.
Here, the image indicates only the image of the finger except for the background plate 7 common to FIGS. 10 and 12. Note that the difference image of the present embodiment is a silhouette image of a finger, and x, y,
It is input to the z calculator 18. X, y, z calculator 1
In 8, an image captured by the electronic camera 4 b is processed and input in the same manner as an image captured by the electronic camera 4 a.
The x, y, z calculator 18 calculates the coordinates of the point P from the difference image based on the images captured by the electronic cameras 4a and 4b.

Next, the coordinate calculation process will be described more specifically. First, a method of calculating the x coordinate and the y coordinate will be described. As shown in FIG. 14, x from the center point p _o of the two-dimensional image sensor 15 to the imaging center point p _a difference image, consider the distance h on the y plane. This distance h depends on the imaging optical lens 6.
, The angle θ formed by the designated point P and the imaging center point l2, the two-dimensional image sensor 15,
It has a relationship represented by the following formula with the distance f between the imaging optical lenses 6. θ = arctan (h / f) (9) Accordingly, h is obtained from the position of the CCD in the two-dimensional image sensor 15 where the silhouette image is detected, and the angle θ is obtained.
Can be requested.

The mounting angle of the electronic camera 4a (the angle formed by the center line 11 of the imaging optical lens 6 and a straight line 13 parallel to the longitudinal side of the coordinate input surface 50 in the drawing) is α. The following relationship exists between the mounting angle α, the angle θ obtained by the equation (9), and the angle β shown in the drawing. β = α−θ (10) From this, it is possible to obtain the angle β by substituting the known mounting angle α and the angle θ obtained by Expression (9) into Expression (10). Further, the x, y, z calculator 18 similarly processes a silhouette image based on a captured image obtained by the electronic camera 4b. Then, the angle β on the electronic camera 4b side is obtained.

The angle β on the side of the electronic camera 4a (for convenience, the angle βa) is the angle corresponding to θ _L used in FIG. 5 and the equations (1) to (4), while the angle β on the side of the electronic camera 4b. Is an angle β (for convenience, an angle βb) is
corresponds to the θ _R. Therefore, when the angle βa on the electronic camera 4a side and the angle βb on the electronic camera 4b side obtained as described above are substituted into the equations (1) to (4) as θ _L and θ _R , respectively, The x coordinate and the y coordinate of the point P can be calculated. x = Ltanβb / (tanβa + tanβb) (11) y = x · tanβa (12)

Next, the z coordinate of the point P will be described. FIG.
5 is a side view showing a state in which one point P on the table input surface 50 is designated with a finger and the finger is lifted on the coordinate input surface 50 as it is. The tip of the finger shown in FIG.
0 is located at a distance d _z away from the surface. This position
It is assumed that coordinates z on the z-axis are set with the surface of the coordinate input surface 50 as the origin. Such z coordinates, by imaging the central point of the difference image of the finger is deviated from the center point p _o of the two-dimensional image sensor 15, x, can be calculated based on the y-coordinate Similarly triangulation. By detecting the z coordinate of the point P, it becomes possible to detect a double click, a pen up, and a pen down. Note that z between the center point p _o and the imaging center point of the difference image
In the present embodiment, the distance in the direction is hereinafter represented by k.

However, the distance k changes not only with the z coordinate of the point P but also with the x and y coordinates. This is shown in FIG.
I will explain using. FIG. 16 is a side view of FIG. 14 as viewed from a direction perpendicular to the paper surface. FIG. 16 shows that the z coordinate is the same and the distance from the imaging optical lens 6 is D1, D2.
Two points P1 and P2 different from 2 are shown. FIG.
According to the above, the points P1 and P on the two-dimensional image sensor 15
2 imaging center points Pk ₁ and Pk ₂ and two-dimensional image sensor 1
It is clear that the distances k1 and k2 from the center point Po of No. 5 are different. That is, the distance D measured in FIG. 14 is also a function of the distance k. For this reason,
In the present embodiment, prior to the calculation of the z coordinate based on the distance k, the x coordinate and the y coordinate are calculated using the above-described equations (9) to (12). Then, after that, the z coordinate is calculated in consideration of the previously calculated x coordinate and y coordinate, and x,
An accurate z coordinate can be obtained regardless of the distance on the y plane.

Next, the processing of the first embodiment described above will be described with reference to a flowchart shown in FIG. First, in the present flowchart, the electronic camera 4
a, a reference image is photographed by the electronic camera 4b and stored in the reference image memory 16a (S1). Then, it is determined whether or not an input has been made on the input surface 50 by the operator (S2). If no input has been made, the process waits until there is an input (S2: No). On the other hand, if there is an input (S2: Yes), an image of the finger is taken (S2).
3) A difference image is generated by calculating a difference from the reference image (S4).

Next, the angle between the electronic camera 4a, the electronic camera 4b and the position of the imaged finger is calculated based on the difference image, and the x and y coordinates of the finger position are further calculated from this angle ( S5). Here, in the present embodiment, it is determined whether or not the coordinates calculated in step S5 are within the range of the non-input area (S6). If it is determined that the area is a non-input area (S6: Yes), non-input processing such as stopping the subsequent processing and not outputting the x and y coordinates, or outputting an error signal is performed. Perform (S
10), and waits for the next input (S2).

Next, the z-coordinate is calculated in consideration of the x- and y-coordinates calculated in step S5 (S7) and output to a personal computer or the like together with the x-y coordinates (S8). Thereafter, it is determined whether or not the coordinate input device is turned off (S9). If the coordinate input device is not turned off (S9: No), the process waits for the next input (S9).
2). When turning off the coordinate input device (S9:
No), all the processing ends.

In the first embodiment described above, the coordinate detection accuracy of the electronic camera can be suppressed to a pixel pitch or less over the entire area of the coordinate input surface of the coordinate input device. Therefore, it is possible to improve the reliability of the coordinate input device and eliminate the variation in the coordinate detection accuracy in the coordinate input plane.

The present invention is not limited to the embodiment described above. For example, instead of the electronic camera as the designated point input means, another optical device for capturing an image of the designated member may be used. Further, the designated point input means is not limited to an optical device, but may be one which calculates an angle with respect to a point input by, for example, an ultrasonic wave and detects the coordinates.

(Embodiment 2) Next, Embodiment 2 of the present invention will be described. The coordinate input device according to the second embodiment is a designated point input unit that provides a non-input area on a non-coplanar surface with a coordinate input surface, and outputs a signal for detecting a finger or the like in parallel with the non-input surface and at a designated point. It is provided with a detection signal deflecting means for deflecting so as to face the electronic camera. In addition,
In the second embodiment, since the detection of the finger is performed by the electronic camera, the detection signal is an image of the finger, and a reflection mirror is used as the detection signal deflection unit.

FIG. 18 is a diagram for explaining the second embodiment. The configuration of the coordinate input device shown in FIG. 18 is such that a coordinate input surface is provided on a CRT (Cathode Ray Tube), a real projection type display, or the like. FIG. 18A is a diagram illustrating the top surface of such a coordinate input device, and FIG. 18B is a diagram illustrating the side surface. FIG.
8, the same members as those shown in FIG. 5 are denoted by the same reference numerals, and the description thereof will be partially omitted.

In the second embodiment, the electronic camera 4a and the electronic camera 4b are installed on the housing 204 of the display (Di), and this installation surface is used as a non-input area. For this reason, the distance d between the end of the upper surface of the housing 204 shown by the broken line 202 and the electronic cameras 4a and 4b is:
The width is set to 0.06 times or more the width of the coordinate input surface. Further, in such a configuration, a reflection mirror 201 that deflects light so that an image of a finger on the coordinate input surface 50 is directed to the electronic camera 4a and the electronic camera 4b is provided. The reflection angle of the reflection mirror 201 is set so that light traveling on a plane parallel to the coordinate input plane 50 travels parallel to the non-input plane. In Embodiment 2, the light is reflected at 90 degrees. Is to be reflected.

FIGS. 19A and 19B are diagrams for explaining another configuration of the second embodiment. FIG. 19A shows a top view of the coordinate input device, and FIG. 19B shows a side view. FIG.
In FIG. 19, the same members as those shown in FIGS. 5 and 18 are denoted by the same reference numerals, and the description thereof will be partially omitted. The configuration shown in FIG. 19 is applied to a case where a coordinate input surface is provided on a plate-shaped member such as a whiteboard, a plasma display, and a liquid crystal display. The electronic camera 4a and the electronic camera 4b are connected to a plate-shaped housing of a display (Di). It is installed on the back of the body 205. And
This installation surface is used as the non-input area G.
For this reason, the distance d between the back end of the housing 205 and the electronic cameras 4a and 4b, which is indicated by the broken line 203, is set to be 0.06 times or more the distance between the electronic cameras.
In addition, in such a configuration, a reflection mirror 201b that once deflects the image of the finger on the coordinate input surface 50 so as to be parallel to the upper surface of the housing 205, and the electronic camera 4a and the electronic camera 4b have a back surface. A reflection mirror 201a that deflects to be parallel is provided. Reflection mirror 201
The reflection angles of a and 201b are set such that the light traveling on a plane parallel to the coordinate input plane 50 travels in parallel with the non-input plane on the back. In the configuration shown in FIG. , Each of which reflects light at 90 degrees.

The second embodiment described above has, in addition to the effects obtained from the first embodiment described above, a space occupied by the non-input surface from the same surface as the coordinate input surface, thereby increasing the size of the coordinate input device. Can be suppressed.

(Embodiment 3) The coordinate input device of Embodiment 3 is provided with light emitting means for emitting light instead of the electronic camera of Embodiment 1 or 2, and the light emitted by the light emitting means is provided. Is configured to detect the coordinates of the input point based on the reflected light. Here, first, the principle of detecting such coordinates will be described with reference to FIGS. FIG. 20 shows a coordinate input surface 50 and light emitting and receiving units 40a and 40b provided in the coordinate input surface 50.
And the reflecting members 80 provided on three sides of the coordinate input surface 50. It is assumed that each of the light emitting / receiving units 40a and 40b includes a point light source 41 and a light receiving element (FIGS. 21 and 22).

The light emitted from the point light source 41 is L1, L2,
... Spread like a light beam with Lm as the optical axis over the entire area of the coordinate input surface. For example, when attention is paid to the optical axis La of such light beams, the reflected light of the light beam of the optical axis La (the optical axis L
a ′) is reflected by the retroreflecting member 80 and is reflected by the optical axis La.
It goes to the light receiving / emitting unit 40a through the same optical axis. The light receiving / emitting unit 40a is provided with a light receiving unit described later, and receives the reflected light. Such light receiving means includes optical axes L1, L
2,..., Lm so as to receive the reflected light.

When the operator places a finger on one point P in the coordinate input surface 50, a part of the light beam represented by the optical axes L 1, L 2,... Lm is blocked by the finger, and does not reach the reflecting member 80. . Therefore, the reflected light of the light beam blocked by the finger is not received by the light receiving means, and the optical axis of the light passing through the point P where the finger is placed can be identified from the light beam not received. Similarly, the light beam emitted from the point light source 41 of the light emitting / receiving unit 40b receives the reflected light, and the optical axis passing through the point P where the finger is placed can be identified. In FIG.
An optical axis L emitted from the light emitting / receiving section 40a and an optical axis R emitted from the light emitting / receiving section 40b are optical axes passing through the point P. The coordinates of the point P can be calculated as such an intersection of the optical axis L and the optical axis R.

Next, the structure of the light emitting / receiving unit 40a and the light emitting / receiving unit 40b and the mechanism for finding the optical axis of the shielded light will be described. The light emitting / receiving sections 40a and 40b have the same configuration. For this reason, in the third embodiment, the light emitting / receiving section 4
Only the configuration relating to 0a is illustrated, and the description relating to the light emitting / receiving unit 40b is omitted.

FIG. 21 is a view schematically showing the structure of the light emitting / receiving section 40a.
FIG. The light receiving / emitting unit 40a is roughly composed of a point light source 41, a condenser lens 42, and a light receiving element 43. The point light source 41 irradiates a fan-shaped light to the opposite side to the light receiving element 43, and the fan-shaped light is a set of luminous fluxes irradiated or reflected in the directions of arrows q, r, s, and t. I believe that. The light emitted in the direction of arrow q is reflected by the reflecting member in the direction of arrow r. Then, the light travels through the condensing lens 42, and the point 4 on the light receiving element 43
The light is received at the position 3b. The light emitted in the direction of arrow s is reflected by the reflecting member in the direction of arrow t, and is received at the position of point 43 a on light receiving element 43.

As described above, the optical axis of light emitted from the point light source 41 and reflected by the retroreflective member has a one-to-one relationship with the light receiving position. From this, the light receiving element 43
By examining the above received light intensity distribution, it is possible to know through which optical axis the shielded light has been irradiated or reflected.
Then, such an optical axis is connected to the light receiving / emitting unit 40a, the light receiving / emitting unit 4
By obtaining both of 0b, two straight lines intersecting at the point input by the finger can be obtained.

FIG. 22 is a diagram for explaining the relationship between the light receiving intensity on the light receiving element 43 and the optical axis of the shielded light. FIG.
Here, the condenser lens 42 is arranged such that the center of the condenser lens 42 coincides with the point light source 41. Light emitted from the point light source 41 is recursively reflected by the reflection member 80 and received on the light receiving element 43 through the center of the condenser lens 42. At this time, the intensity distribution on the light receiving element 43 becomes substantially uniform unless there is a light shielding element on the coordinate input surface. But,
When the light is blocked at the point P in the figure, the light receiving intensity of the light receiving position of the light passing through this point on the light receiving element 43 decreases. Note that such a point on the light receiving element 43 having a low light receiving intensity is hereinafter referred to as a dark point.

[0064] in FIG. 22, showing the position of dark point the distance between the point of the light receiving element 43 centered D _n. The distance Dn, the corresponding relationship represented by an angle theta _n with the following equation, which forms a straight line passing through the center point of the straight line Lm and the light receiving element 43 through the dark point (13). θ _n = arctan (D _n / f) (13) where f in the equation (13) is the distance between the center of the condenser lens 42 and the surface of the light receiving element 43 as shown in FIG.

Here, in particular, the light emitting / receiving section 40 shown in FIG.
If a is represented by θ _n and θ _nL and the angle θ _L shown in FIG. 23 is expressed, θ _L = g (θ _nL ) (14) where θ _nL = arctan (D _nL / f) (15) The relationship between (14) and (15) holds true for the light emitting / receiving unit 40b. Therefore, θ _n on the light emitting / receiving section side
_Is θ _nR and θ _R in FIG. 23 is expressed as _follows : θ _R = h (θ _nR ) (16) where θ _nR = arctan (D _nL / f) (17)

Here, the light emitting / receiving unit 40a and the light emitting / receiving unit 40b
Assuming that the mounting interval is W as shown in FIG. 23 and the origin is o in the figure, the coordinates P (x, y) of the point P are: x = W · tan θ _R / (tan θ _L + tan θ _R ) (18) y = W · tan θ _L · tan θ _R / (tan θ _L + tan θ _R ) (19) As described above, the light emitting / receiving unit 40a,
The coordinates of the point P can be detected by detecting a dark point on the light receiving element 43 provided on the light receiving element 40b and calculating the distance from the dark point to the center of the light receiving element 43.

Next, the configuration of the third embodiment, which is a coordinate input device for detecting the coordinates of a point input based on the above-described detection principle, will be described. The coordinate input device according to the third embodiment includes a coordinate input surface that is a planar coordinate input / detection region, a plurality of light emitting units that emit light to substantially the entire area of the coordinate input surface, and light emitted from the light emitting unit. A reflective member that reflects toward the light-emitting means, and an input unit having a plurality of light-receiving means provided at positions capable of receiving the light reflected by the reflective member, on such an input unit, the light-emitting means, This is a coordinate input device for inputting, as coordinates, a position of a light shielding member that prevents irradiated light from being received by the light receiving unit.

For this purpose, the angle between the straight line passing through the light emitting means and the light shielding member and the straight line passing through the light emitting means is detected by at least two light emitting means. An arithmetic unit having coordinate calculation means for calculating two-dimensional coordinates indicating the position of the light shielding member based on the detected angle and the distance between the light emitting means used for angle detection is provided. In such a configuration, the input unit is provided with a non-input area that does not accept coordinate input by a finger, between the light emitting unit used for angle detection and the coordinate input surface. In addition, the arithmetic unit includes
Personal computers are used.

FIG. 24 is a view for explaining a coordinate input device according to the third embodiment, in which the input section is viewed from the front. In FIG. 24, the same components as those described in FIG. 5 are denoted by the same reference numerals, and the description thereof will be partially omitted. The illustrated coordinate input device includes a coordinate input surface 50, two beam shaping lens groups 102a and 102b serving as light emitting means, and a recursive reflecting member provided so as to surround three sides of the coordinate input surface 50. 80, a laser light source 100 for using a beam shaping lens group as a light emitting unit, a half mirror 101, and a mirror 103. The light emitted from the beam shaping lens group 102a and the beam shaping lens group 102b is reflected by the reflecting member 80 and returns to the beam shaping lens group 102a and the beam shaping lens group 102b again. Beam shaping lens group 102
a, a light receiving element as a light receiving means for receiving such reflected light behind the beam shaping lens group 102b (FIG. 26)
Is provided.

Further, between the beam shaping lens group 102a and the beam shaping lens group 102b and the coordinate input surface 50,
A non-input area G is provided, and the width d is set to a length of 0.06 W or more based on the above-described standard.
It should be noted that such a non-input area is also covered with a cover or the like as in the first embodiment so that the operator can recognize the non-input area, or when the detected coordinates are within the range of the non-input area G. In such a case, the input may not be accepted in such a manner that the coordinates are not returned to the application side.

In the coordinate input device shown in FIG.
The light of No. 00 is transmitted or reflected by the half mirror 101, branched and split into two beam shaping lens groups 102 a,
The coordinate input surface is configured to emit light from two directions via 2b. As such a light source 100, a light source such as a laser diode or a pinpoint LED that can narrow the spot to some extent is used. The beam shaping lens groups 102a and 102b are respectively arranged as shown in FIG.
Shirundical lens 112, Shirundical lens 1
13. It is composed of a cylindrical lens 114. The beam shaping lens groups 102a and 102b correspond to FIG.
As shown in FIG. 4, they are attached at a distance W from each other, and the spot light has a fan-shaped spread (FIG. 25a).
The light beam is shaped into a light beam parallel to the coordinate input surface 50 (FIG. 25).
b). Note that the expression “straight line passing through the light emitting means” in the third and fourth embodiments refers to the beam shaping lens group 10.
A straight line passing through substantially the centers of 2a and 102b is indicated.

FIG. 26 is a diagram for explaining the optical system of the coordinate input device shown in FIGS. 24 and 25 in more detail. FIG. 26 (a) shows the structure of light emission and light reception according to the third embodiment. FIG. 2B is a schematic diagram for explaining, FIG. 2B is a diagram illustrating a configuration related to light emission in the schematic diagram of FIG. 2A, and FIG. 2C is a diagram illustrating a configuration related to light reception in FIG. 26 (a) to 26 (c)
Each is viewed from the direction according to the coordinate axes shown in each figure.

The light from the light source 100 is directed to, for example, the beam shaping lens group 102 a by the half mirror 101, and is then collimated by the cylindrical lens 112 only in the x direction. Further, the cylindrical lens 11
3. Light is collected by the cylindrical lens 114 in the y direction in the figure. The curvature distribution of the cylindrical lens 112, the cylindrical lens 113, and the cylindrical lens 114 is orthogonal to each other. Light that has passed through the three cylindrical lenses is condensed linearly at the light condensing part c. Since this light condensing portion c corresponds to the point light source 41 based on the above-described coordinate detection principle, it will be referred to as a secondary light source hereinafter.

Further, a slit s is provided at an outlet for extracting light from the beam shaping lens group 102a, and light from the secondary light source c is emitted from the slit s toward the coordinate input surface. In the third embodiment, it is assumed that the position of the slit s and the position of the secondary light source c match. This irradiation light
It is folded back by the half mirror 87 and spreads like a fan when viewed from the side of the operator in front of the display (Di) (FIG. 26B). At this time, since the irradiation light is collimated by the cylindrical lens 112, it does not spread in the vertical direction of the coordinate input surface, but becomes light parallel to the coordinate input surface.

The light spread on the coordinate input surface 50 is reflected by the reflecting member 80, and travels through the same optical axis as when emitted, toward the beam shaping lens group 102a. And
After passing through the half mirror 87, the light is received by the light receiving element 43 through the condenser lens 42. The light receiving element according to the third embodiment is configured by arranging a plurality of CCD imaging elements in a matrix. At this time, if there is a finger placed on the coordinate input surface 50 for inputting coordinates, this finger acts as a light shield and no light is received by any of the CCD image pickup elements of the light receiving elements 43. Produces dark spots. CC that became this scotoma
From the position of the D imaging element on the light receiving element 43, D _{n of the} above-described equation (13) is obtained, and the coordinates of the point where the finger is placed can be calculated based on this D _n (FIG. 26C).

According to the third embodiment described above, in the coordinate input device in which the irradiated light is shielded, the coordinate detection accuracy can be suppressed to the pixel pitch or less over the entire area of the coordinate input surface. Therefore, it is possible to improve the reliability of the coordinate input device and eliminate the variation in the coordinate detection accuracy in the coordinate input plane.

(Embodiment 4) Next, Embodiment 4 of the present invention will be described. The coordinate input device according to the fourth embodiment is provided with a non-detection area on a non-coplanar surface with the coordinate input surface, and an optical axis deflection for deflecting the light emitted from the light emitting means so that the optical axis is parallel to the coordinate input surface. Means are further provided.

FIG. 27 is a diagram for explaining the fourth embodiment. In the configuration of the coordinate input device shown in FIG. 27, a coordinate input surface is provided on a CRT, a real projection type display, or the like. FIG. 27 (a)
FIG. 1B is a diagram showing the upper surface of such a coordinate input device, FIG.
FIG. 27, the same members as those shown in FIG. 18 are denoted by the same reference numerals, and the description thereof will be partially omitted.

In the fourth embodiment, the light emitting / receiving unit 40a and the light emitting / receiving unit 40b are installed on the housing 204 of the display (Di), and the installation surface is used as a non-input area. For this reason, the distance d between the end of the upper surface of the housing 204 indicated by the broken line 202 and the light emitting / receiving units 40a and 40b is:
The distance is set to 0.06 times or more of the distance between the light receiving and emitting units.
Further, in the fourth embodiment, a beam shaping lens group for shaping the spot light and a light receiving element are used as the light receiving and emitting units 40a and 40b as in the third embodiment, and both are collectively referred to as a light receiving and emitting unit.

Further, the coordinate input device according to the fourth embodiment includes a reflecting mirror 201 for deflecting the light emitted from the light emitting / receiving unit 40a and the light emitting / receiving unit 40b toward the coordinate input surface 50.
Is provided. The reflection angle of the reflection mirror 201 is set such that the irradiated light travels in parallel to both the non-input surface and the coordinate input surface 50. In the fourth embodiment, the light is reflected at 90 degrees. Has become.

FIG. 28 is a view for explaining another configuration of the fourth embodiment. FIG. 28 (a) shows a top view of the coordinate input device, and FIG. 28 (b) shows a side view. FIG.
In FIG. 28, the same members as those shown in FIGS. 19 and 27 are denoted by the same reference numerals, and the description thereof will be partially omitted.

Such a configuration is applied to a case where a coordinate input surface is provided on a plate-shaped member such as a white board, a plasma display, or a liquid crystal display. The light receiving / emitting unit 40a and the light receiving / emitting unit 40b are connected to a display (Di). On the back of the plate-like housing 205. The installation surface is used as a non-input area. For this,
The back end of the housing 205 and the light emitting / receiving unit 4 indicated by a broken line 203
0a, the distance d from the light emitting / receiving unit 40b is
The distance is set to 0.06 times or more the distance between the light receiving / emitting units 40b.

Further, in such a configuration, the light emitting / receiving section 40 is provided.
a, the light emitted from the light emitting / receiving unit 40b is
Reflection mirror 201 that deflects so as to be parallel to the upper surface of 05
a, and a reflection mirror 201b that deflects the light so as to be parallel to the coordinate input surface 50 is provided. Reflection mirror 20
The reflection angles of 1a and 201b are set so that the light traveling on a plane parallel to the non-input surface travels in parallel with the coordinate input surface 50. In the configuration shown in FIG. Light is reflected at 90 degrees.

In the fourth embodiment, in addition to the effects obtained in the third embodiment, the space occupied by the non-input surface can be reduced, and the size of the coordinate input device can be suppressed. .

The present invention is not limited to the third and fourth embodiments described above. That is, the light-emitting unit and the light-receiving unit (light-receiving / emitting unit) may have any configuration as long as it is generally applied to a coordinate input device. As an optical mechanism applicable to the coordinate input device according to the third and fourth embodiments, for example,
It is conceivable that the irradiating unit scans light in the input coordinate plane and that the reflecting member is provided on the surface of the cylindrical body. It is also possible to use one that detects light blocking using electrical phototransistor compensation for ambient light.

[0086]

The present invention described above has the following effects. In other words, the invention according to claim 1 avoids calculating the coordinates of a point input to a part having a particularly low detection accuracy in the coordinate input / detection area, and increases the coordinate detection accuracy of the coordinate input device. The reliability of the device can be improved. Therefore, the first aspect of the present invention can provide a coordinate input device that eliminates a variation in detection accuracy within a coordinate input surface and in which an error in a detection angle hardly affects the coordinate detection accuracy.

According to the second aspect of the present invention, the optimum width of the non-detection area can be set, and the coordinate detection can be substantially performed while minimizing the reduction of the coordinate input surface due to the provision of the non-detection area. A region where the accuracy is reduced can be set as a non-detection region.

According to the third aspect of the present invention, the coordinate input / detection area can be made wider, and the size of the coordinate input device can be reduced.

According to a fourth aspect of the present invention, there is provided a coordinate input device for detecting a point input by blocking emitted light, wherein the input is made to a portion having a particularly low detection accuracy in a coordinate input / detection area. For points, avoid calculating these coordinates, improve the coordinate detection accuracy of the coordinate input device,
The reliability of the device can be increased. Therefore, according to the present invention, in a coordinate input device for detecting a point input by shielding emitted light, a variation in detection accuracy in a coordinate input plane is eliminated, and an error in detection angle is eliminated. Can provide a coordinate input device that hardly affects the coordinate detection accuracy.

According to a fifth aspect of the present invention, in a coordinate input device for detecting a point input by blocking emitted light, an optimum width of a non-detection area can be set, and The area where the detection accuracy of the coordinate is substantially reduced can be set as the non-detection area while minimizing the reduction of the coordinate input surface due to the provision.

According to a sixth aspect of the present invention, in a coordinate input device for detecting a point input by blocking emitted light, a coordinate input / detection area can be made wider, and the coordinate input device can be reduced in size. It can also be converted.

[Brief description of the drawings]

FIG. 1 is a diagram illustrating a method of calculating the coordinates of a point by a triangulation method.

FIG. 2 is a diagram showing a coordinate variation amount as a distribution in a coordinate input plane.

FIG. 3 is a sectional view of FIG. 2 taken along a straight line E shown in FIG. 2;

FIG. 4 is a diagram schematically showing a non-input area.

FIG. 5 is a diagram for explaining an input unit according to the first embodiment;
It is a front view of an input part.

FIG. 6 is a cross-sectional view of the input unit taken along line VV ′ in FIG. 5;

FIG. 7 is a diagram for explaining a light shielding plate according to the first embodiment.

FIG. 8 is a diagram for explaining a background plate according to the first embodiment;
It is a front view which shows a part.

FIG. 9 is a block diagram for explaining a calculation unit according to the first embodiment;

FIG. 10 is a diagram illustrating a reference image according to the first embodiment;

FIG. 11 is a diagram for explaining operations of the input unit and the calculation unit according to the first embodiment, and is a diagram illustrating a state where a point is input on the coordinate input surface.

FIG. 12 is a diagram for explaining operations of the input unit and the calculation unit according to the first embodiment, and is a diagram illustrating an image captured by the electronic camera in FIG. 11;

FIG. 13 is a diagram for explaining operations of an input unit and a calculation unit according to the first embodiment, and is a diagram for explaining a series of processes of coordinate input.

FIG. 14 is a diagram for explaining operations of an input unit and a calculation unit according to the first embodiment, and is an enlarged view of the electronic camera in FIG. 11;

FIG. 15 is a diagram illustrating a state where a finger is lifted on the coordinate input surface according to the first embodiment;

FIG. 16 is a diagram of FIG. 14 viewed from a direction perpendicular to the paper surface.

FIG. 17 is a flowchart illustrating a process according to the first embodiment;

FIGS. 18A and 18B are views for explaining the coordinate input device according to the second embodiment, in which FIG.
(B) is a figure which shows a side surface.

FIG. 19 is another view for explaining the coordinate input device according to the second embodiment, in which (a) shows a top view of the coordinate input device;
(B) is a figure which shows a side surface.

FIG. 20 is a diagram for explaining the principle of coordinate detection of the coordinate input device according to the third embodiment.

FIG. 21 is another diagram illustrating the principle of detecting coordinates of the coordinate input device according to the third embodiment;

FIG. 22 is another diagram illustrating the principle of coordinate detection of the coordinate input device according to the third embodiment;

FIG. 23 is another diagram illustrating the principle of detecting coordinates of the coordinate input device according to the third embodiment;

FIG. 24 is a diagram for explaining the coordinate input device according to the third embodiment, where the input unit is viewed from the front.

FIG. 25 is a diagram for explaining the configuration of the beam shaping lens group shown in FIG.

26A and 26B are diagrams for explaining the optical system of the coordinate input device shown in FIGS. 24 and 25 in more detail, where FIG. 26A is a schematic diagram for explaining the configuration of light emission and light reception, and FIG. Is
FIG. 3A is a schematic diagram illustrating a configuration related to light emission in a schematic diagram, and FIG.
It is a figure explaining composition concerning light reception of (a).

FIGS. 27A and 27B are diagrams illustrating a coordinate input device according to a fourth embodiment, where FIG. 27A illustrates a top view of the coordinate input device;
(B) is a figure which shows a side surface.

FIG. 28 is another diagram for explaining the coordinate input device according to the fourth embodiment, in which (a) is a diagram showing an upper surface of the coordinate input device;
(B) is a figure which shows a side surface.

[Explanation of symbols]

 2 Support 4a, 4b Electronic Camera 5, 50 Coordinate Input Surface 6 Imaging Optical Lens 7 Background Plate 9 Interface 10 CPU 11 ROM 12 RAM 12a Coordinate Memory 13 Timer 14 Integrator 15 2D Image Sensor 16 EEPROM 16a Reference Image Memory 18 xyz calculator 20, 251 Notch 25 Light shield 40a, 40b Light emitting / receiving section 51 Boundary line

Claims (6)

[Claims] 1. A planar coordinate input / detection area, and a plurality of designated point input means for detecting a designated member that designates a point on the coordinate input / detected area and inputting the position of the designated point The angle formed by a straight line passing through the designated point input means and the designated member and a straight line passing through the designated point input means is at least 2 degrees.
Angle detecting means for detecting each of the designated point input means, an angle detected by the angle detecting means, and a designated member designated based on a distance between the designated point input means used for angle detection. Coordinate calculating means for calculating two-dimensional coordinates of a point, wherein the designated point input means is provided between the designated point input means used for angle detection and the coordinate input / detection area. A non-input area which does not accept input of a point by a coordinate input device. 2. The non-input area has a predetermined width represented by a shortest distance between a boundary between the coordinate input / detection area and a straight line passing through the designated point input means used for angle detection. The coordinate input device according to claim 1, wherein the predetermined width is at least 0.06 times the distance between the designated point input means used for angle detection. 3. The non-detection area is provided on a non-coplanar surface with the coordinate input / detection area, and a signal for detecting the designated member is directed in parallel with the non-input area and toward the coordinate input means. 3. The coordinate input device according to claim 1, further comprising a detection signal deflecting means for deflecting as described above. 4. A planar coordinate input / detection area, a plurality of light emitting means for irradiating substantially the entire area of the coordinate input / detection area, and a light emitted from the light emitting means directed to the light emitting means. And a plurality of light receiving means provided at positions where the light reflected by the reflecting member can be received. On a coordinate input / detection area, the light emitted by the light emitting means receives the light received by the light receiving means. A coordinate input device for inputting, as coordinates, a position of a light shielding member that prevents light from being received by the unit, and an angle between a straight line passing through the light emitting unit and the light shielding member and a straight line passing through the light emitting unit. Angle detecting means for detecting at least two of the light emitting means, an angle detected by the angle detecting means, and a position of the light shielding member based on a distance between the light emitting means used for angle detection. A coordinate calculating means for calculating two-dimensional coordinates, wherein a non-input that does not accept a coordinate input by the light shielding member is provided between the light emitting means used for angle detection and the coordinate input / detection area. A coordinate input device provided with an area. 5. The non-input area has a predetermined width represented by a shortest distance between a boundary between the coordinate input and detection area and a straight line passing through the light emitting means used for angle detection. 5. The coordinate input device according to claim 4, wherein said predetermined width is at least 0.06 times the distance between said light emitting means used for angle detection. 6. The non-detection region is provided on a non-coplanar surface with the coordinate input / detection region, and is deflected so that an optical axis of light emitted from the light emitting means is parallel to the coordinate input / detection region. The coordinate input device according to claim 4, further comprising an optical axis deflecting unit.