JPH032512A - Three-dimensional position recognition device - Google Patents

Abstract

PURPOSE:To recognize the three-dimensional position of a dynamic body to be measured by rotating a scanning means which has at least two reflecting surfaces and making a horizontal or vertical linear scan, and rotating the other scanning means and making a vertical or horizontal two-dimensional scan. CONSTITUTION:The position recognition device consists of a light source 11, a projection lens 12, a photodetection lens 16, a photodetecting element 17 for position detection, and an arithmetic means. Further, a scanning mirror M1 and a movable coil 14 constitute a galvanometer as a horizontal scanning means. A both-surface mirror M1 is fixed on the rotary shaft of the coil 14 and the light beam from the lens 12 scans the body 13 to be measured horizontally by the rotation. The light beam is reflected by the mirror M1, deflected by a fixed mirror M2, and made incident on a scanning mirror M3. A mirror M3 and a movable coil 15 constitute the galvanometer as a vertical scanning means. The mirror M3 is fixed on the rotary shaft of the coil 15 and the light beam from the mirror M2 is reflected by the mirror M3 through the rotation to make a vertical scan on the body 13 to be measured.

Description

Detailed Description of the Invention [Industrial Field of Application] The present invention utilizes reflected light from a fixed object A+++ to
This invention relates to a three-dimensional position recognition device that recognizes the position of a constant object in three dimensions.

[Conventional technology]

FIG. 7 shows the optical system of a typical distance detector.

A light emitting beam from a light source is focused and irradiated onto an object to be measured 3 by a light projecting lens 2, and the reflected light is focused by a light receiving lens 4 onto a light receiving element 5 for position detection.

Here, calculate the distance from the light receiving lens 4 to the object to be measured 3,
When the M-line length is 81 and the distance between the light-receiving lens 4 and the position detection light-receiving element 5 is f, the distance X from the optical axis center of the light-receiving lens 4 to the center of gravity of the spot light is expressed by the following equation .

x=f-B/L... (1) By finding the distance X in equation (1) indicating the displacement using the position detection light receiving element 5, the distance can be found conversely.

In addition, the distance detector is mechanically moved on a plane that is perpendicular to the plane of the figure and includes the base line length direction, and the position (X, Y) of the distance detector on this two-dimensional plane and the distance from the position detection light receiving element 5 are measured. The distance in the Z-axis direction was determined from the obtained displacement position X, and the three-dimensional position (X, Y, Z,) was recognized.

[Problem to be solved by the invention]

However, in the conventional three-dimensional position recognition device described above, the distance detector itself must be mechanically moved on the (X, Y) plane. Therefore, it takes a long time to perform one measurement for three-dimensional position recognition. For this reason, conventional devices can be applied to 3D position recognition for static UJ objects, but cannot be practically applied to 3D position recognition for dynamic objects. The problem was that it was not possible.

[Means to solve the problem]

The present invention has been made to solve this problem, and one of the scanning means has at least two reflecting surfaces, and when rotated or rotated, the scanning means can be rotated or rotated to reflect light from the light projecting means. It consists of a reflector that scans the light beam horizontally or vertically on the object to be measured, and uses another surface to deflect the reflected light from the object to the light receiving means. It is composed of a reflector that vertically or horizontally scans the light beam onto the object to be measured and deflects the reflected light from the object to the light receiving means.

[Effect]

The light beam emitted from the light source is horizontally or vertically scanned one-dimensionally by rotating or rotating a scanning means having two reflective surfaces, and the other scanning means is rotated or rotated. Vertical or horizontal two-dimensional scanning is performed.

〔Example〕

FIG. 1 is a perspective view showing a configuration according to an embodiment of the present invention, and each three-dimensional direction is determined by each direction indicated by the (x, yZ) coordinates in the same figure.

The light source 11 is composed of, for example, a light emitting diode.
The luminous flux emitted from
The light is focused on the top. Further, the scanning mirror M and the galvanometer 4 constitute horizontal scanning means. The scanning mirror M1, which is a flat double-sided mirror, is fixed to the rotating shaft of the galvanometer 4, and is rotated in the direction of the arrow in the figure as the rotating shaft rotates. This rotation axis coincides with the Z-axis direction, which is the direction of the object to be measured, and due to this rotation, the irradiated light beam from the projecting lens 2 is horizontally scanned over the object 13 to be measured.

In addition, the irradiation light flux from the light projection lens] 2 is transmitted to the scanning mirror M
The light is reflected by the fixed mirror M2, and is incident on the scanning mirror M3. The scanning mirror M3 and the galvanometer 5 constitute vertical scanning means. The scanning mirror M3, which is a flat mirror, is fixed to the rotating shaft of the galvanometer 5, and is rotated in the direction shown by the arrow in the figure as the rotating shaft rotates. This rotation axis coincides with the horizontal X-axis direction perpendicular to the Z-axis, and due to this rotation, the irradiated light beam from the fixed mirror M is reflected by the scanning mirror M3 and is vertically scanned on the object to be measured 13. .

The reflected light beam from the object to be measured 1.3 is reflected by the scanning mirror M3.
d and is deflected by fixed mirror M4.

The fixed mirror M4 is arranged symmetrically with respect to the fixed mirror M2 with respect to the Z-axis, and the deflected reflected light beam is further reflected by the scanning mirror M and is incident on the light receiving lens]6. This light-receiving lens] 6 condenses the reflected light beam from the scanning mirror M1, and irradiates the light-receiving surface of the position detection light-receiving element 17 with a repulsive light beam.

A calculation means (not shown) is connected to the position detection light receiving element 17, and when the distance to the object 1B changes, the convergence position of the reflected light beam on the light receiving surface of the position detection light receiving element 17 changes from this distance. changes in proportion to the amount of change. Then, the optical output current proportional to this amount of change is given to the calculation means, and the calculation means calculates the distance [(L) to the object to be measured 13 in the Z-axis direction based on this output signal. In addition, the X-axis and Y-axis of the light beam irradiated from the scanning mirror M3 onto the object to be measured]3
The scanning angle (θ , θ ) of χ・j about the axis is χ
It can be determined from the scanning signal sent to the y Luhanometer 14.15, and three-dimensional position recognition is possible from this scanning angle and the distance (L) to the object Δ1.

FIG. 2 is a configuration diagram of a general semiconductor device detector used as the position detection light receiving element 17. As this semiconductor device detector, for example, there is a one-dimensional semiconductor device detector manufactured by Hamamatsu Photonics Co., Ltd. with the model number S 1545,
A case in which this semiconductor device detector is used will be described below.

The semiconductor device detector 25 includes an n+ type half layer 27, a high resistance n type semiconductor layer 28, and a p type soil conductor layer 2 with uniform resistivity.
9 is formed by sequentially stacking layers. n
The type semiconductor layer 28 and the two p-type soil conductor layers constitute a photodiode.

Further, the n+ type half body layer 27 is provided with a common electrode 30 for applying a reverse bias voltage to the photodiode, and a pair of electrodes 31.
32 are provided.

When a predetermined voltage is applied to the common electrode 30 of the semiconductor device detector 25 and a light spot is incident on the position SP, an electron-hole pair is generated at the pn junction below the position SP. The photocurrent 1 proportional to the incident energy of the light spot is
o flows from the common electrode 30 toward the two p-type soil conductor layers.

Here, the distance between the electrodes 31 and 32 is 01, the resistance of the two p-type soil conductor layers between them is R6, and the distance between the light spot incident position SP and the electrode 32 is xl. Assuming that the resistance is R, the photocurrent 1o is resistance-divided at the light spot incident position SP.

That is, the current IA to the electrode 3 and the current IB to the electrode 32 are respectively expressed by the following equations.

I = I [R/Ro] A Ox l = I [(RR), /Rc] ... (2
)B OCX Furthermore, as described above, since the resistivity of the p-type soil conductor layer 29 is uniformly distributed, this equation (2) can be transformed as follows.

■ -I -X/C O 1=I [(C-x)/C] ... (3
) As can be seen from equation (3), the current 1, I is A
I ( taken out from the electrodes 31 and 32 and subjected to a predetermined analog calculation process by a predetermined calculation means, the electrode 32
The distance X from to the light spot incident position SP can be determined.

FIG. 3 is a diagram illustrating the principle of scanning the irradiation light beam in the three-dimensional position recognition device configured as described above. Note that, to simplify the drawing, the vertical scanning means consisting of the scanning mirror M3 and the galvanometer 5 is omitted from the drawing.

The irradiation light flux emitted from the light source 11 is focused on the object to be measured]3, but when the scanning mirror M1 is located at the position indicated by the solid line, the irradiation light flux emitted from the light source 11 is focused on the object to be measured. It follows the optical path shown by and is reflected by the scanning mirror M1. Further, the light flux follows the optical path of the solid line and is reflected by the fixed mirror M2, and then irradiates the irradiation position s1 on the target lpJ treasure 13 in the form of a spot light. In addition, the object to be measured 13
The reflected light follows the solid line optical path and is reflected by the fixed mirror M4, then further reflected by the scanning mirror M, and is focused by the light receiving lens 16 onto the light receiving surface of the position detecting light receiving element 17.

Here, when the scanning mirror M1 rotates to the position M' shown by the two-dot chain line, the irradiation light beam emitted from the light source 11 follows the optical path shown by the two-dot chain line and reaches the scanning mirror M1.
reflected. Further, the light beam follows the optical path indicated by the two-dot chain line and is reflected by the fixed mirror M2, and then irradiates the irradiation position s2 on the object to be measured 13 in the form of a spot light. Irradiation position S2
The reflected light from the fixed mirror M follows the optical path indicated by the two-dot chain line.
After being reflected by the scanning mirror M', the light is irradiated onto the light-receiving surface of the position detection light-receiving element 17 by the light-receiving lens]6.

In this way, according to the present scanning method, even if the irradiation light beam is deflected from the irradiation IM, position S to 82 on the target treasure [a1]3, if the distance to the target treasure]3 is constant,
The condensing position of the irradiation light beam condensed onto the light-receiving surface of the position detection light-receiving element 17 does not change.

FIG. 4 is a diagram for explaining the principle of distance detection in an optical system using the three-dimensional position recognition device configured as described above,
FIG. 2 is a view of the device shown in FIG. 1 viewed from the (X, Z) plane. Note that, in order to simplify the drawing, the vertical scanning means consisting of the scanning mirror M3 and the galvanometer 5 is omitted from the drawing. In addition, there are 13 objects to be measured. , the convergence position of the irradiation light beam focused on the light receiving surface of the position detection light receiving element 17 is the electrical center position of the position detecting light receiving element 17, that is, the two obtained photocurrents IA] 1 ' It is set to match the incident position where each value of +3 is equal.

Here, when the object δ1 [treasure] 3 moves by ΔL and reaches the position 13' shown by the two-dot chain line, the reflected light from the object to be measured 13 follows the optical path shown by the two-dot chain line to the fixed mirror M4. It is further reflected by the scanning mirror M. The light beam reflected by the scanning mirror M1 is focused by the light-receiving lens 16 on the light-receiving surface of the position-detecting light-receiving element 7 at a position ΔX away from the electrical center position. Further, in the principle of triangulation, the positions of the light projecting lens 12 and the light receiving lens ]6 are equivalent to the positions of the lenses 12' and 16' indicated by dotted lines by the scanning mirrors M 1 and M 2 . Therefore, the base line length B in triangulation corresponds to the distance between the optical axes of the lenses 12' and 16' at equivalent positions.

If the distance between the light-receiving lens 16 and the light-receiving part of the position detection light-receiving element 7 is f, then the above equation (1) (X=f'-B/L
) holds true, and the following equation (4) holds true between the displacement amount ΔL of the distance and the displacement amount ΔX of the light condensing position on the light receiving surface of the position detection light receiving probe]7.

Δx=f-B・+1/(Lo-8L)]/L)
...(4) Displacement amount ΔX on the light-receiving surface of position detection light-receiving element] 7
is determined by performing a predetermined analog calculation based on the obtained signal photocurrents I and I. Then, using the obtained ΔX, the distance to the target A+++ treasure 3' after moving by ΔL.

ΔL is obtained from equation (4).

Therefore, the three-dimensional position data (X, Y, Z) representing the irradiation point of the light beam focused on the object to be measured 13 is determined by the two deflection angles θ.
, θ, using the following equations (5) to X 3/ (7).

Z=L...(5) Y=L-t
anθ, −(6)X=L−tanθ,
・'(7) As described above, according to this embodiment, the light source 1
The light flux irradiated from the object 13'' is horizontally scanned, that is, scanned in the X-axis direction, by rotating the scanning mirror M constituting the horizontal scanning means.

Further, by rotating the scanning mirror M3 constituting the vertical scanning means, the irradiation light beam is vertically scanned on the object to be measured 13, that is, scanned in the Y-axis direction. As a result, the apparatus according to the above embodiment can be applied to three-dimensional position recognition of a dynamic object to be measured.

Further, the condensing position of the irradiation light beam on the position detection light receiving cable 17 moves only when the distance to the object to be measured 13 changes, corresponding to the amount of change in this distance. Therefore, the light-receiving area of the position detection light-receiving element 17 can be suppressed to the minimum area, and the provided device can be made smaller and less expensive.

FIG. 5 is a perspective view showing the configuration of a three-dimensional position recognition device according to another embodiment of the present invention.

The light beam emitted from the light source 4 is focused onto the at++ treasure 43 by the projection lens 42. The irradiation light beam is reflected by one surface of a rectangular prism-type polygonal mirror M5, is deflected, and is incident on a scanning mirror M6. The scanning mirror M6 and the galvanometer 44 constitute vertical scanning means. The scanning mirror M6 is fixed to the rotation axis of the galvanometer 44, and this rotation axis is arranged in the horizontal X-axis direction orthogonal to the Z-axis direction, which is the direction of the object to be measured. Then, by rotating this rotating shaft in the direction shown by the arrow in the figure,
The light flux incident on the scanning mirror M6 is vertically scanned on the object to be measured 43.

The light beam reflected by the scanning mirror M6 is transferred to the polygon mirror M7.
is incident on the The polygon mirror M7 and the servo motor 45 constitute horizontal scanning means. Polygon mirror M
7 is fixed to a rotating shaft of a servo motor 45, and this rotating shaft is arranged in the vertical Y-axis direction. Then, by rotating this rotation axis in the direction shown by the arrow in the figure, the light beam incident on the polygon mirror M7 is horizontally scanned on the object to be measured 43. The light beam reflected by the polygon mirror M7 is incident on the beam splitter M8, which is a flat fixed mirror, and is reflected onto the subject d1 of foot movement 43. Further, this beam splitter M8 transmits a small amount of light flux, and the light is condensed by a light receiving lens (not shown) disposed behind the beam splitter M8. Furthermore, the focused light flux is irradiated onto a position detection light receiving element (not shown), and a calculation means (not shown) connected to this position detection light receiving element
The deviation angles (θ 2 , θ 2 ) of the light beam irradiated onto the object to be measured 43 with respect to the X-axis and Y-axis are determined.

y The reflected light beam from the object to be measured 43 is reflected by a fixed mirror M9, which is a total reflection mirror, and is deflected, and then enters the polygon mirror M7 again. The fixed mirror M is arranged symmetrically about the Z-axis with respect to the beam splitter M8.

The light beam incident on the polygon mirror M is sent to the scanning mirror M6.
The light beam reflected by the scanning mirror M6 is deflected by the polygonal mirror M5. The deflected light beam is condensed by a light receiving lens 46 and sent to a position detecting light receiving element 47.
The light is irradiated onto the light-receiving surface of the This position detection light receiving element 47
consists of the semiconductor device detector shown in FIG. 2, which is similar to the previously described embodiment. The light-receiving element 47 for position detection is connected to a calculation means (not shown) in 6 stages, and based on the optical output current output from the light-reception element 47 for position detection, the calculation means calculates the
Calculate the distance (L) to treasure 43.

Then, three-dimensional position recognition of (x, y, z) is performed from the above-mentioned declination angles (θ 2 , θ 2 ) and this distance y (L).

FIG. 6 is a diagram showing the principle of the scanning method in the three-dimensional position recognition device having the above configuration. In addition, to simplify the drawing,
Vertical scanning means composed of a scanning mirror M6 and a galvanometer 44 and a polygonal mirror M5 are omitted from the figure.

The polygon mirror M7 is rotated at high speed in the direction shown by the arrow in the figure, and the scanning of the irradiation light beam is faster than in the device of the above-described embodiment in which the flat mirror is shaken by a galvanometer. The light beam from the light source 41 is condensed by the projection lens 42, and is incident on the polygon mirror M7. The irradiation light beam incident on the polygon mirror M7 is deflected by the beam splitter M8, and is irradiated onto the object to be measured 43. Further, a part of the light beam incident on the beam splitter M8 is transmitted through the beam splitter M8, and is focused onto the position detection light receiving cable 49 by the light receiving lens 48 arranged behind the beam splitter M8. The position detection light receiving element 49 is composed of a semiconductor device detector for two-dimensional detection, unlike the one-dimensional detection of the position detection light-receiving element 47.

The reflected light flux from the fixed object 43 is fixed mirror M9.
The beam is deflected by the polygon mirror M7, and is reflected by the polygon mirror M7. The reflected light flux enters the light receiving lens 46 a.
The light is focused and irradiated onto the position detection light receiving element 47. In the method of scanning the illumination fAJ light flux from the light source 41 in this embodiment, as in the embodiment described above, if the distance to the object to be measured 43 does not change, even if the illumination light flux is horizontally and vertically scanned, the position The condensing position of the illumination η·j beam condensed onto the detection light-receiving cable 47 does not change.

Furthermore, the method for detecting the distance to the object to be measured 43 is also substantially the same as in the embodiment described above. In other words, the position detection light receiving cable 4
The amount of displacement ΔX of the irradiation light beam focused on 7 is expressed as the optical output current 1
, I and calculate the distance (L) to the object to be measured 43 from equation (4) of B mentioned above. Therefore, in this embodiment as well, the three-dimensional position data (X, Y, Z) representing the irradiation point of the light beam focused on the object to be measured 43 has two deviation angles (θ , θ ).
It can be obtained by calculating the above-mentioned equations (5) to (7) based on the distance 1iiIll(L) and y.

In this way, also in this embodiment, the light fAJ is emitted from the light source 4].
The light flux is vertically scanned, that is, scanned in the Y-axis direction, on the object to be measured 43 by rotating the mirror Me that constitutes the vertical scanning means.

Further, by rotating the polygon mirror M7 constituting the horizontal scanning means, horizontal scanning, that is, scanning in the X-axis direction is performed. As a result, the device according to this embodiment can be applied to three-dimensional position recognition for dynamic treasures, as in the previously described embodiments.

〔Effect of the invention〕

As explained above, according to the present invention, the light beam emitted from the light source is transmitted in one dimension in the horizontal or vertical direction by rotating or rotating one stage of the scanner having two sides with anti-U; t'm. Scanning is performed in row 1), and vertical or horizontal two-dimensional scanning is performed by rotating or rotating the other scanning means.

Therefore, the scanning performance of the light beam emitted from the light source is increased, and the time required for three-dimensional position recognition is shortened. As a result, there is an effect that an apparatus is provided that can target dynamic objects to be measured, for which three-dimensional position recognition has conventionally been difficult.

be.

1. Light source, ] 2. Light projection lens, 13. Object to be measured, ], 4. , 1.5... Garno 1 nometer, 16...
・Light receiving lens, 17... Light receiving element for position detection, MI'
M3...Scanning mirror, M, M4...Pair of fixed mirrors

[Brief explanation of drawings]

Claims (1)

[Scope of Claims] 1. A light source, a light projecting means for condensing a luminous flux emitted from the light source onto an object to be measured, and a light receiving means for receiving and condensing the reflected light from the object to be measured; a position detection light receiving element that detects the focusing position of the light beam focused by the light receiving means;
A three-dimensional position recognition device comprising: a calculation means for calculating a distance to an irradiation point of the light beam focused on the object to be measured based on an output signal of the position detection light receiving element; The method further includes horizontal scanning means and vertical scanning means for deflecting and scanning the light beam from the optical means horizontally and vertically, and one of the horizontal scanning means and the vertical scanning means has at least two reflective surfaces. , is rotated or rotated, so that one of the two surfaces scans the light beam from the light projecting means horizontally or vertically on the object to be measured, and the other surface scans the object to be measured. The other scanning means vertically or horizontally scans the light beam from the light projecting means onto the object to be measured, and the other scanning means deflects the reflected light from the object to the light receiving means. A three-dimensional position recognition device comprising a reflector that deflects reflected light from the light toward the light receiving means. 2. The horizontal scanning means is composed of a flat double-sided mirror that is rotatable around the direction of the object to be measured, and uses one surface to scan the light beam from the light projecting means horizontally on the object to be measured. At the same time, the reflected light from the object to be measured is deflected to the light receiving means by the other surface, and the vertical scanning means is composed of a flat mirror rotatable about the horizontal direction, and 2. The three-dimensional position recognition device according to claim 1, wherein the light beam from the optical device vertically scans the object to be measured, and the reflected light from the object to be measured is deflected to the light receiving device. 3. The horizontal scanning means is composed of a polygon mirror that is rotatably provided around the vertical direction, and horizontally scans the object to be measured with the light beam from the light projecting means, and also scans the reflected light from the object. The vertical scanning means is composed of a flat mirror that is rotatably provided around a horizontal direction, and directs the light beam from the light projecting means onto the object to be measured perpendicularly. 2. The three-dimensional position recognition device according to claim 1, wherein the three-dimensional position recognition device scans and deflects reflected light from the object to be measured to the light receiving means.