JP3196861B2 - Object position detection method and object position detection device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an object position detecting method and an object position detecting apparatus, and can be applied to a method for easily detecting an object position such as a so-called touch panel input device.

[0002]

2. Description of the Related Art As a method for detecting the position of an object existing in a substantially rectangular area in a situation where the demand for the resolution of a detection position is not strict, there are the following methods conventionally used in a touch panel input device. Can be mentioned.

In a first detection method, as shown in FIG. 6, a plurality of light emitting elements 11 are juxtaposed at a fixed interval, and light receiving elements 12 corresponding to the respective light emitting elements 11 are arranged at the same interval. The light emitting elements 11 are juxtaposed with respect to the detected object 10 from the position of the light receiving element 12 which cannot receive the emitted light from the light emitting element 11 due to the light shielding of the detected object 10. This is a method of detecting the position of the detected object 10 by detecting the position in the line direction and performing such detection in two directions.

In a second detection method, as shown in FIG. 7, two resistance plates 21 and 22 having a uniform resistance value per unit area are provided slightly apart from each other, With the two resistance plates 21 and 22 in contact with each other by pressure,
From the linear terminal 21a of one resistance plate 21 to the other resistance plate 2
A current is passed to the second linear terminal 22a to detect a resistance value (or a current value), and this resistance value measurement is repeated a plurality of times while changing the input / output linear terminals, and an arithmetic operation is performed from the obtained plurality of resistance values. This is a method of detecting the position of the detected object 20.

[0005]

However, both of the two types of object position detection methods described above have low reliability. That is, according to the first method, when one of the light emitting element or the light receiving element fails, one of the XY coordinates of the element cannot be obtained,
The probability of occurrence of such an inconvenient state is considerably high due to the large number of elements, and as a result, the reliability is low. In addition, according to the second method, even when the resistance plates 21 and 22 are released from the pressing force, short-circuiting is likely to occur due to deformation or the presence of dust, and the reliability is low.

Further, the first detection method requires a large number of elements, and is difficult to be applied to a case where the detection area of the object position is wide due to the complicated structure and the reliability described above. Therefore, its application has been limited to applications such as touch panel input devices having a narrow detection area. Also, the second detection method is based on the premise that the two resistance plates 21 and 22 are provided slightly apart from each other.
It is difficult to increase the size of the touch panel and the size of the touch panel, and therefore, the application of this detection method is also limited to applications such as a touch panel input device having a narrow detection area. That is, both of the conventional detection methods have a low degree of freedom with respect to the detection area of the object position.

[0007] The touch panel input device is usually provided in front of the display surface of the display device, and is used to transmit display contents. In the above-described second detection method, the resistance plates 21 and 22 are configured to have a light transmitting property. However, a decrease in the amount of light cannot be avoided beyond the resistance plates 21 and 22, and some deterioration of the display content cannot be avoided. Further, as long as the resistance plates 21 and 22 are present, the amount by which the object can be moved in the vertical direction of the object detection surface is restricted, so that it is difficult to apply to applications for detecting an object that crosses the object detection surface in the vertical direction. is there. Furthermore, it is premised on the pressing force, and it is difficult to apply it to an application for detecting a naturally existing object.

The present invention has been made in view of the above points, and has as its object to provide an object position detecting method and an object position detecting device having high reliability and versatility.

[0009]

In order to solve such a problem, a first object position detecting method according to the present invention is a method for detecting an object position, comprising: two reflectors installed in parallel so that their reflection surfaces face each other; A spatial transmission wave from an object to be detected in an area sandwiched between the two reflectors is reflected n times (where n ≧ 0) by the two reflectors. When arriving at the distance measurement device, the distance measured by the distance measurement device, the measurement direction of the distance measurement device, and the distance between the two reflectors, the virtual object position of the detected object, The number of reflections n is obtained, and the position of the detected object in an area sandwiched between the two reflectors is determined from the virtual object position of the detected object and the number of reflections. .

A second object position detecting device according to the present invention comprises two reflectors installed in parallel so that the reflecting surfaces face each other, and a distance measuring device, wherein the two reflectors are provided. The spatially transmitted wave from the object to be detected in the region sandwiched between the two reflectors is reflected n times (where n ≧
0) is repeated to reach the distance measuring device, the distance measured by the distance measuring device, the measurement direction of the distance measuring device,
The virtual object position of the detected object and the number of reflections n are obtained from the distance between the two reflectors, and the virtual object position of the detected object and the number of reflections are used to obtain the two object positions. And a distance / position converting means for determining the position of the detected object in the area sandwiched between the reflectors.

[0011]

The present invention aims to solve the conventional problems by detecting a two-dimensional position as one-dimensional information called distance and converting it to two-dimensional information. In addition, as a distance measuring method, not only a method using an electromagnetic wave (preferably light) but also a method using an ultrasonic wave or the like may be used.

In the present invention, the detection area is sandwiched between two parallel reflectors, and electromagnetic waves, ultrasonic waves, and the like from an object to be detected in the detection area are reflected by these reflectors. Therefore, the distance measuring device can measure the distance to the detected object while utilizing the reflection from each reflector. The pair information of the measured distance between the distance measuring device and the detected object and the measurement direction at the time of the measurement is one-to-one with the two-dimensional position of the detected object.
The two-dimensional position of the detected object is determined from the measurement distance and the measurement direction.

[0013]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the object position detecting device according to the present invention will be described below in detail with reference to the drawings. FIG. 1 is a block diagram showing the configuration of this embodiment.

In FIG. 1, a detection area (detection surface) 2 in which an object to be detected 1 is allowed to be positioned is composed of two reflection plates 3 installed in parallel so that the reflection surfaces face each other.
And 4.

In this embodiment, an optical distance measuring device 5 is provided near one end of the reflecting plate 3. The direction of measurement by the distance measuring device 5 is on the surface of the detection region (detection surface) 2, and the angle θ with respect to the reflection plate 3 is smaller than 90 degrees and is directed to the direction of the detection region 2. Hereinafter, this angle θ is referred to as a measurement direction). Therefore, the distance measuring device 5 does not measure the direct distance to the detected object 1 located in the detection area 2 (although in such a case), and the number of reflections at the incident angle θ is several. The distance to the object to be detected 1 is measured on a path repeated (including 0 times). In this embodiment, a distance measuring device 5 that can change the measuring direction θ is applied.

Here, as the optical distance measuring device 5, various well-known devices can be applied and are not limited. When the size of the detection area 2 is about the size of a touch panel input device, various types used for an automatic focusing device of a camera can be applied.
It is preferable that there is no light emission from the lens. When the distance d between the reflection plates 3 and 4 is sufficiently large and the detection area 2 is large, it is possible to apply a distance measuring device 5 that emits a laser and measures the distance based on the reflected light information. it can. In this case, the detection target object 1 also emits an incident light beam having a so-called corner cube body on its surface.
It is necessary to apply something that is deflected by degrees.

The distance measuring device 5 gives the distance L to the detected object 1 obtained by the measurement and the measuring direction θ at that time to the distance / position converting means 6.

The distance / position conversion means 6 is realized by, for example, a microcomputer or the like.
From the information on the given distance L and the measurement direction θ, as will be described later, for example, the two-dimensional coordinates (x0, y0) of the detected object 1 with the position of the optical distance measuring device 5 as the origin position are determined. Find and output.

FIGS. 2 and 3 are explanatory diagrams of the conversion processing executed by the distance / position conversion means 6, respectively. FIG. 2 shows that the number of reflections by the reflectors 3 and 4 is an even number (2n times: n is 0). , 1, 2,...), And FIG.
Odd number of reflections by reflectors 3 and 4 (2n + 1)
It is for the case of.

The distance measuring device 5 uses the reflection to detect the object 1 to be detected.
Is to directly measure the object to be detected at the position 1a which is separated from the distance measuring device 5 by the distance L in the measurement direction θ without using reflection, as shown in FIGS. Is equivalent to

The x coordinate x of such a virtual object position 1a
1 and y coordinate y1 are x coordinates x0 and y of object 1 to be detected.
Using the coordinate y0, when the reflection is an even number of times, it can be expressed as in Equations (1) and (2), and when the reflection is an odd number of times, Equations (3) and (4) Can be expressed as

Even number of reflections x1 = 2nd + x0 (1) y1 = y0 (2) Odd number of reflections x1 = (2n + 2) d-x0 (3) y1 = y0 (4) Also, virtual object position X coordinate x1 and y coordinate y1 of 1a
Is expressed using the distance L and the measurement direction θ that have been measured and known, when the number of reflections is an even number, and when the number of reflections is an odd number, as expressed by Equations (5) and (6). Can be.

X 1 = L sin θ (5) y 1 = L cos θ (6) Accordingly, by rearranging the expressions (1) to (6), the x coordinate x 0 and the y coordinate y 0 of the detected object 1 can be obtained. When the number of reflections is an even number, they can be expressed as in Equations (7) and (8), and when the number of reflections is an odd number, Equations (9) and (1)
It can be expressed as equation (0).

Even number of reflections x0 = L sin θ-2nd (7) y0 = L cos θ (8) Odd number of reflections x0 = -L sin θ + (2n + 2) d (9) y0 = L cos θ (10) Here, since x0 is a value satisfying 0 ≦ x0 ≦ d,
From equations (7) and (9), L sin θ satisfies the inequality in equation (11) when the reflection is an even number, and satisfies the inequality in equation (12) when the reflection is an odd number. It turns out to be something.

Even number of reflections 2nd ≦ L sin θ <(2n + 1) d (11) Odd number of reflections (2n + 1) d ≦ L sin θ <(2n + 2) d (12) Therefore, the known distance L and measurement direction θ L s required by
The value of the integral part of the multiple of the known value (distance between the reflectors 3 and 4) d is determined by calculating the number of reflections 2
n or (2n + 1) can be obtained, and it is naturally possible to determine whether the number of reflections is even or odd. Then, information of the determined number of reflections is expressed by Expressions (7) and (8),
Alternatively, by applying to equations (9) and (10), the coordinates (x0, y0) of the detected object 1 can be determined.

As described above, according to the above embodiment, the object position detecting device is constituted by the set of parallel reflectors 3, 4, the distance measuring device 5, and the distance / position converting means 6, and the number of components , The reliability is high, and the possibility of economical construction is high.

Further, according to the above embodiment, even when the detection area 2 is large, the object position detection device can be configured without requiring any new components, and the degree of freedom with respect to the detection area is large.

Further, according to the above embodiment, the detection area 2
Since there is no configuration for detecting the object position in the vertical direction, the present invention can be applied to an apparatus that performs some function in the vertical direction of the detection area 2. For example, when the object position detecting device of this embodiment is applied to a touch panel input device, the display content of the display device does not become difficult to see due to the position detecting configuration.

Furthermore, according to the above-described embodiment, since the distance measuring device 5 that can change the distance measuring direction θ is applied, the object position can be detected over the entire detection area 2.

The present invention is not limited to the above embodiment. Some other examples are as follows.

(1) The measuring direction θ of the distance measuring device 5 may be fixed. When the detected object 1 is large and the measurement direction θ is a value close to 90 degrees, the object 1 can be detected in almost the entire detection area 2 even if the measurement direction θ of the distance measuring device 5 is fixed.

(2) The distance measurement by the distance measuring device 5 is performed twice or more while changing the measurement direction θ, and the average value of the object position coordinates obtained for each distance measurement is set as the output coordinate. By doing so, the accuracy of the output coordinates can be improved.

(3) Two or more distance measuring devices 5 are applied from the following viewpoints. For example, when there is an upper limit on the measurable distance of the distance measuring device and the entire detection area 2 cannot be covered by one distance measuring device 5, as shown in FIG.
a and 5b are responsible for parts 2a and 2b of the detection area 2, respectively. Also in this case, the reflectors 3 and 4 are commonly used by two or more distance measuring devices 5. When three or more distance measuring devices 5 are applied, an opening may be provided in a part of the reflector 3 or 4, and the distance measuring device may measure the distance from the opening.

(4) Two or more distance measuring devices 5 are applied from the following viewpoints. For example, a distance measuring device having a fixed measurement direction θ
As shown in FIG. 5, two or more distance measuring devices 5a and 5b complement the measurement of a position that is difficult to measure with one distance measuring device in relation to the measurement direction θ.

(5) Two or more distance measuring devices 5 are applied in order to improve measurement accuracy. The average value of the measured coordinates of each distance measuring device is set as the output coordinate.

(6) The area between the reflectors 3 and 4 is made larger than the detection area 2 in the direction in which the reflectors extend. Many of the distance measuring devices 5 have a lower limit of the measurable distance and cannot measure a distance less than a certain value. According to the lower limit distance, a part of the area sandwiched by the reflectors 3 and 4 is removed. This is a non-detection area.

(7) The distance measuring device 5 may be replaced with an optical one, and may be a device to which a spatially propagating wave such as an ultrasonic wave or an electromagnetic wave other than light, which has a property of being reflected, is used.

[0038]

As described above, according to the present invention, there are provided two reflectors provided in parallel so that the reflecting surfaces face each other, and a distance measuring device, and the reflection by each reflector is utilized. While measuring the distance to the object to be detected in the detection area sandwiched between the two reflectors, the position of the object to be detected is determined from the measured distance and the measurement direction. An object position detection method and an object position detection device with high reliability and versatility can be realized.

[Brief description of the drawings]

FIG. 1 is a block diagram illustrating a configuration of an embodiment.

FIG. 2 is an explanatory diagram of a conversion principle (part 1) of distance and position coordinates in the embodiment.

FIG. 3 is an explanatory diagram of a conversion principle (part 2) of distance and position coordinates according to the embodiment.

FIG. 4 is an explanatory diagram of another embodiment (part 1).

FIG. 5 is an explanatory diagram of another embodiment (part 2).

FIG. 6 is an explanatory diagram of a first conventional method.

FIG. 7 is an explanatory diagram of a second conventional method.

[Description of Signs] 1 ... detected object, 2 ... detection area, 3, 4 ... reflector, 5 ...
Optical distance measuring device, 6... Distance / position conversion means.

Continuation of the front page (56) References JP-A-57-60204 (JP, A) JP-A-49-74050 (JP, A) JP-A-63-157003 (JP, A) JP-A-59-119206 (JP, A) JP-A-58-13328 (JP, A) JP-A-59-14082 (JP, A) JP-A-1-295214 (JP, A) (58) Fields investigated (Int. Cl. ⁷ , DB G01S 7/48-7/51 G01S 17/00 G01B 11/00-11/30 G06F 3/03

Claims (2)

(57) [Claims] An object is provided with two reflectors, which are installed in parallel so that their reflection surfaces face each other, and a distance measuring device, and detects an object to be detected in an area sandwiched between the two reflectors. When the spatial transmission wave reaches the distance measuring device by repeatedly reflecting n times (where n ≧ 0) on the two reflectors, the distance measured by the distance measuring device and the distance measuring device From the measurement direction and the distance between the two reflectors, the virtual object position of the detected object and the number of reflections n are obtained, and the virtual object position of the detected object and the number of reflections are calculated. Determining the position of the object to be detected in the area sandwiched between the two reflectors. 2. A device comprising two reflectors, which are installed in parallel so that their reflection surfaces face each other, and a distance measuring device, wherein the object to be detected is located in a region sandwiched between the two reflectors. When the spatial transmission wave reaches the distance measuring device by repeatedly reflecting n times (where n ≧ 0) on the two reflectors, the distance measured by the distance measuring device and the distance measuring device From the measurement direction and the distance between the two reflectors, the virtual object position of the detected object and the number of reflections n are obtained, and the virtual object position of the detected object and the number of reflections are calculated. An object position detecting apparatus, further comprising a distance / position converting means for determining a position of an object to be detected in an area sandwiched between the two reflectors.