JPS6355481A - Device for generating line object rotary laser beam in plane position detecting device using laser - Google Patents

Abstract

PURPOSE:To obtain a line object rotary laser beam having high accuracy by constituting the titled device so that a laser beam is reflected two times in a prism and a mirror. CONSTITUTION:A pentagonal prism 5 is installed in the center of a rotary base 3 which is rotated on a horizontal plane by a motor 2, and a laser oscillator 4 is provided on a revolving shaft 2a of the motor 2. Also, on the rotary base 3, a composite prism 6 is installed in the optical axis direction of the prism 5, and a right-angle mirror 7 is provided on a fixed part. In this state, when the motor 2 rotates, the rotary base 3 rotates clockwise, and the prisms 5, 6 rotate at a prescribed speed. A laser beam from the oscillator 4 is curved by 90 deg. by the prism 5, divided into two by the prism 6, and one of them is emitted as one of line object beams, namely, a counterclockwise laser beam CCW, and the other is made incident on the mirror 7. The laser beam which has been made incident on the mirror 7 is reflected by the mirror 7, and emitted as the other of the line object beams, namely, a clockwise laser beam CW. In this way, a line object rotary laser beam is obtained.

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention is based on the principle of triangulation! ! f [Relates to a device that creates a line-symmetric rotating laser and a light beam in a device that uses a laser to detect a plane position when determining the coordinates of a point.

[Prior art and its problems] The conventional method of determining a plane position by triangulation is usually carried out using a transit, and when using a transit, it requires ±1 surveyor to operate the transit and work with a pole. This method requires at least two people to work together, requires skill, and is time-consuming.

Therefore, the present applicant previously filed a patent application for a method of measuring meters using a laser (Patent application No. 60-267481).
issue). In this method, when determining the coordinates of a measurement point using the principle of triangulation, a laser lighthouse is installed at two reference points that irradiates two line-symmetrical beams at an even rotational speed, and each axis of interest is set as the reference point of the other. Align with the direction of the point, while
A sensor that detects laser light and an accurate time measurement device are installed at the measurement point to measure the time gap between detecting two symmetrical beams emitted by the laser lighthouse, and input this to a calculation device to determine the measurement point. The method is to convert the coordinates of the measurement point into an angle between the symmetrical axis of the laser beam and the symmetrical axis of the laser beam, and then determine the coordinates of the measurement point from that angle and the distance of the reference point that has been measured in advance.The problem with this method is that The point is that the installation of the prisms, mirrors, etc. that make up the laser lighthouse, that is, the device that creates the line-symmetric rotating laser beam, must be done with extremely high precision.

The present invention provides a device that can create a line-symmetric rotating laser beam with extremely high precision by canceling installation errors of the prism or mirror by reflecting the laser beam twice in the prism or mirror. This is something that has been done as much as possible.

[Means for Solving the Problems] In FIGS. 1 and 2, a pentaprism is mounted at the center of a rotary table 3 that is rotated on a horizontal plane by a motor 2 that rotates at an even speed with a vertical axis as the rotation axis. 5 is installed, and a laser oscillator 4 is installed on the rotating shaft 2a of the motor 2. Furthermore, a compound prism 6 is installed on the rotary table 3 in the optical axis direction of the pentaprism 5, and the compound prism 6 has a beam splitter and two right-angled reflecting surfaces.

A right-angle mirror 7 is installed on the fixed part so that the intersection part "1" of the mirror is perpendicular to and intersects with the rotation axis 2a of the motor 2.

[Operation of the invention] In FIGS. 1 and 2, as the motor 2 rotates, the rotary table 3 rotates in the clockwise direction indicated by the arrow, and the pentaprism 5 and the compound prism 6 rotate unevenly at a predetermined rotational speed. It rotates without any problem.

The laser beam from the laser oscillator 4 passes through the pentaprism 5
can be bent 90 degrees by The laser beam from the pentaprism 5 is divided into two by a compound prism 6, one of which is emitted to the outside as one of the line-symmetrical laser beams, that is, a counterclockwise laser beam CCW, and the other is returned to the center of rotation after changing its height. The laser beam returned to the center of rotation is reflected by the right-angle mirror 7 as the other line-symmetrical beam, that is, the clockwise laser beam CW. This makes it possible to obtain a line-symmetric rotating laser beam.

[Effects of the invention] The laser beam is bent by 90 degrees and 180 degrees by the prism and mirror, but since it is reflected twice in the prism and mirror, the angle of incidence is adjusted by canceling out the prism and mirror mounting errors in the bending direction. Can be bent 90 degrees or 180 degrees. FIG. 3(c) shows a mode of canceling out the mounting error α in the pentaprism. Naturally, the shaft vibration of the motor can also be offset.

[Example] Embodiments of the present invention will be described below with reference to the drawings.

It is equipped with a mounting frame 1 that has an almost mouth-like shape when viewed from the side.
A rotary table 3 is provided on the lower horizontal portion 1a of the pedestal 1 and is rotated by a motor 2 that rotates at an even rotational speed about a vertical axis. Also, the mount 1 has a motor 2.
A laser oscillator 4 is mounted on the rotating shaft 2a.

A pentaprism 5 is installed on the rotary table 3 at the center of the rotary table 3, and a pentaprism 5 is installed on the rotary table 3.
A composite prism 6 is installed in the optical axis direction. In addition, a right-angle mirror 7 is mounted on the upper horizontal part 1b of the mounting frame 1 (fixed part).
The intersection point n of the mirror is the rotation axis of the motor (laser optical axis)
It is attached so as to be perpendicular to and intersect with 2a.

A pentaprism 5, a compound prism 6, and a right-angle mirror 7 are shown in FIGS. 3 to 5. Pentaprism 5 is the third
As shown in Figures (a) and (b), the angle formed by the two surfaces has 45 reflective surfaces.

As shown in FIGS. 4(a) and 4(b), the composite prism 6 has two reflecting surfaces with an angle of 90 degrees, and one surface serves as a beam splitter 6a.

The right-angle mirror 7 has an angle of 90 angles between its two sides.

As the motor 2 rotates, the rotary table 3 rotates in the clockwise direction indicated by the arrow, and accordingly, the pentaprism 5 and the composite prism 6 rotate evenly at a predetermined rotation speed. The laser beam from the laser oscillator 4 is bent by 90 degrees by the pentaprism 5. The laser beam from the pentaprism 5 is split into two by a compound prism 6, one of which is one of the symmetrical beams, i.e. the counterclockwise laser beam C.
Take it outside as CW, and change the height of the other one and return it to the center of rotation. The laser beam returned to the center of rotation is reflected by the right-angle mirror 7 as the other side of the diagonal target beam, that is, the clockwise laser beam sicw. This makes it possible to obtain a line-symmetric rotating laser beam. In FIG. 2, m is the line symmetry axis.

FIGS. 6 to 8 show how the laser beam is reversed (with respect to the symmetrical axis) due to reflection on a part of the right-angled mirror. In FIG. 6, the laser beam has an incident angle of 451 m with respect to the mirror. In Figure 7, the laser beam is on optical path planes A, B, and C.
pass inside. A//B, A10, B Sat C. The laser beam incident on the line symmetry axis m at an angle θ in the B plane is A
It has an angle θ with respect to m in the plane. In FIG. 8, when the mirror is viewed from above, a point on the mirror beam n is taken as a reflection point (the laser beam is reflected line-symmetrically).

The laser beam is 90 degrees with prism 5.6 and mirror 7, 18
Although it is bent at 0 degrees, it is reflected twice in prism 5.6 and mirror 7, so the angle of incidence can be bent to 90 degrees and 180 degrees by canceling out the prism and mirror installation errors in the bending direction. . FIG. 3(C) shows a mode in which the installation error α is canceled out in the pentaprism 5. Naturally, the axial vibration of the motor 2 can also be offset.

[Brief explanation of the drawing]

The drawings show an embodiment of the invention, and FIGS. 1 and 2 show an apparatus for producing a line-symmetric rotating laser beam, FIG. 1 being an elevational view, FIG. 2 being a plan view, and FIGS. 3 to 5. Figure 3 (a) shows a pentaprism, a compound prism, and a right-angle mirror.
is a side view of the pentaprism, FIG. 3(B) is a front view, FIG. 3(C) is a side view showing cancellation of installation errors, FIG. Figure 5 (b) is a front view, Figure 5 (a) is a side view of the right-angle mirror, Figure 5 (b) is a front view, and Figures 6 to 8 show the inversion of the laser beam due to reflection on a part of the right-angle mirror. 6 is a side view, FIG. 7 is a bird's-eye view, and FIG. 8 is a top view. 1...Mounting frame 2...Motor 3...Rotary table 4...Laser oscillator 5...Penta prism 6...Complex prism 7...Right angle mirror

Claims (1)

[Claims] A pentaprism is installed at the center of a rotating table that is rotated on a flat surface by a motor that rotates at an even speed.
A laser oscillator is installed on the rotating shaft of the motor, and the laser beam from the laser oscillator is transmitted through a pentaprism.
A compound prism is placed in the direction of the optical axis of the pentaprism on a rotating table with a 0 degree bend, and the compound prism has a beam splitter and two right-angled reflective surfaces, which splits the laser beam from the pentaprism into two. One side is sent out as one of the line-symmetric laser beams, and the other is returned to the center of rotation by changing the height. A right-angle mirror is installed on the fixed part so that the intersection of the mirrors is perpendicular to and intersects with the rotation axis of the motor. In a planar position detection device using a laser, the laser beam returned to the rotation center by a compound prism is reflected as the other side of the line-symmetric rotating laser beam, thereby obtaining a line-symmetric rotating laser beam. equipment for making.