JPH06281423A - Three-dimensional measuring device - Google Patents

Abstract

PURPOSE:To avoid generation of the dead angle, and realize a lightweight and compact driving mechanism of a universal head. CONSTITUTION:A half mirror 4 is arranged between a projector 1 and a subject 2 to be measured with the angle of inclination relative to the optical axis of the light projected from this projector 1, and a part of the reflected light by the subject 2 to be measured is reflected by this half mirror 4 to be received by a camera 3.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a three-dimensional measuring device for measuring the position or shape of an object to be measured by triangulation by projecting light on the object to be measured and receiving the reflected light. is there.

[0002]

2. Description of the Related Art Conventionally, light is projected from a light projecting means such as a projector onto an object to be measured, and the reflected light from the object is received by a light receiving means such as a CCD camera. There is known a three-dimensional measuring device that measures the position and shape of the object to be measured by triangulation.

FIG. 4 shows a conventional three-dimensional measuring device. In this conventional three-dimensional measuring apparatus, a projector 21 and a CCD (charge coupled device) type camera 2 are used.
2 and 3 are mounted on separate pans (not shown), and the projector 21 and the camera 22 are arranged on the left and right sides of the object 23 to be measured.

As a technique related to the present invention, a technique in which an image of an object to be measured is input to a camera via a half mirror is disclosed in, for example, Japanese Patent Laid-Open No. 12210/1992.

[0005]

However, when the projector and the camera are arranged on the left and right with respect to the object to be measured as in the above-described conventional three-dimensional measuring apparatus,
Since there is a blind spot in the portion indicated by the diagonal line A in FIG. 4, there is a problem in that this portion cannot be measured.

Further, in this conventional three-dimensional measuring apparatus, since the projector and the camera are mounted on different pans, respectively, there is a problem that the drive mechanism for these pans becomes large.

It should be noted that the one disclosed in the above-mentioned official gazette shown as a related technique is a passive type three-dimensional measuring apparatus in which a plurality of cameras are used by using a half mirror or the like in order to recognize an object shape at high speed. An optical system for equalizing an obtained image with an image in one line-of-sight direction is provided, and the above-described optical three-dimensional measuring apparatus having a light projecting means and a light receiving means as in the present invention is used. It does not disclose means for solving such a problem.

The present invention has been made in view of the above problems, and makes it possible to avoid the occurrence of blind spots in a three-dimensional measuring apparatus, and at the same time, reduces the weight of the platform driving mechanism. The purpose is to be able to achieve compactness.

[0009]

The present invention is based on the finding that the occurrence of a blind spot can be avoided by matching the optical axes of the light projecting means and the light receiving means.

That is, the three-dimensional measuring apparatus according to the present invention receives a light projecting means for projecting light onto the object to be measured and a light reflected by the object to be measured by the light projected by the light projecting means. In the three-dimensional measuring apparatus including the light receiving means, the half mirror is provided in the optical path from the light projecting means to the object to be measured, and the half mirror is reflected by the half mirror or passes through the half mirror to measure It is characterized in that a part of the reflected light from the object is received by the light receiving means.

The light projecting means, the light receiving means and the half mirror are fixed on one horizontal support base, and the support base is supported on the platform so as to be rotatable about a vertical axis and a horizontal axis. Preferably. In that case, the light projecting means, the light receiving means, and the half mirror on these supports are
It is preferable to cover the optical path from the half mirror to the object to be measured with a dustproof cover.

[0012]

In the present invention, a half mirror is provided in the optical path from the light projecting means to the object to be measured, and the reflected light from the object to be measured is reflected by the half mirror or passed through the half mirror. Since a part of the light is received by the light receiving means, the optical axis of the light irradiated to the object to be measured and the optical axis of the light reflected from the object to be measured can be made to coincide with each other. It is possible to avoid the occurrence of blind spots in three-dimensional measurement. Further, by making the respective optical axes coincide with each other in this way, the light projecting means, the light receiving means and the half mirror can be fixed on one horizontal support base, and this support base can be mounted on the pan head. In addition, it can be rotatably supported around a vertical axis and a horizontal axis, and thereby the drive system can be made compact and highly accurate.

[0013]

EXAMPLES Next, specific examples of the three-dimensional measuring apparatus according to the present invention will be described with reference to the drawings.

A principle block diagram of a three-dimensional measuring apparatus according to an embodiment of the present invention is shown in FIG. The three-dimensional measuring apparatus of this embodiment projects a laser beam from the projector 1 onto the object to be measured 2, and obtains an image obtained by photographing the surface of the object to be measured 2 with the laser light with the camera 3. An active three-dimensional measurement method that recognizes the position and shape of the object 2 to be measured from data by triangulation is used. As a basic idea, the optical axis of the projector 1 and the camera 3 are used. The optical axes are made to coincide with each other, so that the blind spot portion A as shown in FIG. 4 is eliminated. However, when the projector 1 and the camera 3 are arranged as shown in FIG. 1, the camera 3 itself becomes an obstacle this time, and a blind spot region is formed on the surface of the object 2 to be measured. In the example, as shown in FIG. 2, the half mirror 4 is provided between the projector 1 and the DUT 2 with an inclination angle of 45 ° with respect to the optical axis of the light projected from the projector 1. A part of the light which is arranged and is reflected by the DUT 2 after passing through the half mirror 4 is reflected by the half mirror 4 and is received by the camera 3. Further, in that case, a point on the optical axis cannot be triangulated in principle, so the coordinate value of this point can be obtained by interpolation calculation from the triangulation results of 4 points or 8 points around the optical axis. By arranging the projector 1, the camera 3 and the half mirror 4 as in this embodiment, the camera 3 does not become an obstacle and the occurrence of a blind spot as in the conventional device can be avoided.

FIG. 3 shows a specific device configuration of the three-dimensional measuring device of this embodiment. As shown in the figure, in this embodiment, a platform 6 is installed on the base frame 5, and a flat plate-shaped support platform 7 is fixed on the platform 6. Here, the platform 6 is rotatable about a vertical axis (direction of arrow B) and a horizontal axis (direction of arrow C) by a drive mechanism such as a motor and a gear (not shown), whereby the support base 7 supports the support. It is rotatable in a plane including the base 7 and tiltable about a central axis that traverses the support base 7. A projector 1, a camera 3 and a half mirror 4 having the configuration shown in FIG. 2 are provided on the upper surface of the support base 7. The optical axis of the projector 1 has a support base 7
Is arranged in such a manner that it is oriented in the longitudinal direction and passes through the center of the rectangular half mirror 4, and the optical axis of the camera 3 is orthogonal to the optical axis of the projector 1 and passes through the center of the half mirror 4. The camera 3 is arranged as described above. The half mirror 4 is arranged at an angle of 45 ° with respect to each optical axis. Also,
The upper part of the support base 7 is covered with a dustproof cover 8 except for the periphery of the optical path from the half mirror 4 to the DUT 2.

In the three-dimensional measuring apparatus configured as described above, when light such as laser light is projected from the projector 1 during three-dimensional measurement of the object to be measured 2, this light passes through the half mirror 4. Then, the surface of the object to be measured 2 is irradiated, and the reflected light from the object to be measured 2 reaches the half mirror 4 through the optical path of the same optical axis as the irradiation light, and is partially reflected by the half mirror 4. Then, the light is received by the camera 3.
In this way, the position and shape of the DUT 2 are measured by triangulation. In this measurement, when the position or the like of the object to be measured 2 changes, the platform 6 is adjusted in the directions of the arrow B and the arrow C in FIG. 3 accordingly, and the gaze direction of the projector 1 is changed accordingly.

According to this embodiment, the optical axis of the light radiated to the object to be measured 2 and the optical axis of the light reflected from the object to be measured 2 can be made to coincide with each other, so that the occurrence of a blind spot is avoided. can do. Further, since the projector 1, the camera 3 and the like can be fixed on the same support base 7, the gaze direction of the projector 1 and the like can be adjusted by controlling the rotation of one pan 6 and the drive system. It is possible to obtain a measuring device that is compact and highly accurate, and that can be sufficiently used even on a robot.

Although the projector 1 is arranged so as to face the object to be measured 2 in the above embodiment, the positions of the projector 1 and the camera 3 are interchanged with each other so that the camera 3 faces the object to be measured 2. It is also possible to place it in position.

[0019]

Since the present invention is constructed as described above, it is possible to avoid the occurrence of blind spots in three-dimensional measurement, and, in the case of using a pan head, a drive system for driving the pan head. Compactness and high precision can be achieved.

[Brief description of drawings]

FIG. 1 is a diagram showing a principle configuration of a three-dimensional measuring apparatus according to an embodiment of the present invention.

FIG. 2 is a layout explanatory diagram of each device in the three-dimensional measuring apparatus according to the embodiment of the present invention.

FIG. 3 is a schematic configuration diagram showing a specific device configuration of a three-dimensional measuring device according to an embodiment of the present invention.

FIG. 4 is an explanatory view showing a conventional three-dimensional measuring device.

[Explanation of symbols]

 1 Projector 2 Object to be Measured 3 Camera 4 Half Mirror 6 Head 7 Support 8 Dust Cover

Claims (4)

[Claims] 1. A three-dimensional measuring apparatus comprising: a light projecting means for projecting light onto an object to be measured; and a light receiving means for receiving reflected light of the light projected by the light projecting means from the object to be measured. In the above, a half mirror is provided in the optical path from the light projecting means to the object to be measured, and this half mirror reflects a part of the reflected light from the object to be measured so that the light receiving means receives the light. A three-dimensional measuring device characterized in that 2. A three-dimensional measuring apparatus comprising: a light projecting means for projecting light onto an object to be measured; and a light receiving means for receiving reflected light of the light projected by the light projecting means from the object to be measured. In the above, a half mirror is provided in the optical path from the light projecting means to the object to be measured, and a part of the reflected light from the object to be measured is passed through the half mirror to be received by the light receiving means. A three-dimensional measuring device characterized in that 3. The light projecting means, the light receiving means and the half mirror are fixed on one horizontal support base, and the support base is supported on the platform so as to be rotatable about a vertical axis and a horizontal axis. The three-dimensional measuring device according to claim 1 or 2. 4. The tertiary according to claim 3, wherein the light projecting means, the light receiving means and the half mirror on the support base are covered with a dustproof cover except for the periphery of the optical path from the half mirror to the object to be measured. Original measuring device.