JPH09292225A - Laser projecting device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a laser projecting device in which the structure is simplified to reduce the cost, and the focusing of a laser beam can be performed with a high working efficiency. SOLUTION: In a laser projecting device having a laser diode 1 for emitting a laser beam and a projecting lens 2 for converging the laser beam to emit the laser beam from the projecting lens 2 onto a wall surface 4, this device has a glass disc 3 having a plurality of parallel flat parts differed in thickness to be selectively inserted into the optical, path between the laser diode 1 and the projecting lens 2, and a pulse motor 8 for rotating the glass disc 3. When the glass disc 3 is rotated by the pulse motor 8 to change the parallel flat part to be inserted into the optical path, the optical path length from the laser diode 1 to the projecting lens 2 is changed, the focus distance from the projecting lens 2 to the focusing position of the laser beam converged by this lens 2 is changed. Thus, the focusing position of the laser beam emitted to the wall surface 4 can be regulated stepwise.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a laser projection device used for horizontal and vertical measurement work in construction work and general survey work.

[0002]

2. Description of the Related Art Conventionally, as this type of laser light projecting device, for example, one shown in FIG. 13 has been known. A leveling screw 101 for leveling is provided at the lower end of the main body 100 of the laser projector. A laser diode 102 is provided above a base portion 100a of the main body 100. Above the laser diode 102, a light projecting lens 103 is adhered and fixed to a moving hardware 104.
The movable hardware 104 is slidably fitted to the linear guide mechanism 105 and can move straight in the optical axis direction. Further, the moving hardware 104 is engaged with the ball screw 106. A gear 107 is fixed to one end of the ball screw 106.
07 is a gear 1 fixed to the output shaft of the pulse motor 108
It meshes with 09.

Above the light projecting lens 103, there is provided a rotating unit 110 for deflecting the laser beam in the vertical direction from the light projecting lens 103 in the horizontal direction and scanning in the 360 ° direction. The rotation unit 110 is a pentamirror 1
11 and is supported by the main body 100 via a bearing 112 so as to be rotatable about a vertical direction. The rotation of the motor 113 is transmitted to the rotation unit 110 by the transmission belt 114.
Is transmitted via

For example, when performing a horizontal measuring operation using such a laser projector, the apparatus is first installed and leveling is performed with three leveling screws 101. Two rod-shaped bubble tubes (not shown) are provided in the main body 100 in two orthogonal directions, and the leveling is performed while observing these bubble tubes.
After the leveling is completed, the laser light 120A emitted from the laser diode 102 in the vertical direction passes through the light projecting lens 103, then is deviated in the horizontal direction by the pentamirror 111, and passes through the transparent glass 115 for waterproofing. The transmitted horizontal laser light 120B is scanned in the 360 ° direction by the rotation of the rotary unit 110, and the vertical wall surface 116 is scanned.
Form a horizontal surface on top.

At this time, the operator looks at the laser beam 120B irradiated on the wall surface 116 so that the beam diameter becomes the smallest, that is, the laser beam 120B is at the wall surface 1.
The remote controller or the like is operated so that the image is focused on 16. By this operation, the pulse motor 108 is controlled, the rotation of the motor 108 is transmitted to the movable hardware 104 via the gears 109 and 107, and the ball screw 106, and the light projecting lens 103 moves in the optical axis direction.

[0006]

However, in the above conventional technique, the laser light from the light projecting lens 103 is applied to the wall surface 1.
In order to focus on 16, the light projecting lens 103 is moved in the optical axis direction by operating a remote controller or the like. Therefore, the linear guide 105, the ball screw 106, etc. for moving the light projecting lens 103 straight in the optical axis direction are used. There is a problem that a complicated mechanism is required and the manufacturing cost becomes high.

In addition, since the focus position of the laser beam applied to the wall surface 116 is adjusted steplessly, the wall surface 116 is adjusted to the wall surface 116 whenever the optical distance from the projection lens 103 to the wall surface 116 changes. While watching the emitted laser light, the focus position of the laser light must be precisely adjusted,
Poor workability.

The present invention has been made in view of the above circumstances, and an object thereof is to provide a laser projection device capable of focusing laser light with high work efficiency while simplifying the structure and reducing the cost. Is to provide.

[0009]

In order to solve the above-mentioned problems, a laser projecting device according to a first aspect of the invention comprises a light source for emitting a laser beam and a projecting lens for condensing the laser beam. A laser projecting device for irradiating a surface to be measured with a laser beam from the projecting lens, which is selectively inserted in an optical path between the light source and the projecting lens to give different optical path length changes. It is characterized by comprising a plurality of optical path length changing parts and a focus adjusting means for selecting one of the plurality of optical path length changing parts and inserting it into the optical path.

When one of the plurality of optical path length changing parts inserted in the optical path is changed, the optical path length from the light source to the light projecting lens is changed, whereby the laser light condensed by the lens from the light projecting lens is changed. The focus distance to the in-focus position of changes. Therefore, the focus adjusting means selects one of the plurality of optical path length changing parts and inserts it into the optical path, so that the laser beam emitted to the surface to be measured is irradiated without moving the light projecting lens in the optical axis direction. The focus position of can be adjusted stepwise.

According to a second aspect of the present invention, there is provided a laser projection device in which the plurality of optical path length changing portions are respectively formed of a plurality of transparent substantially parallel plane portions having different thicknesses or refractive indexes. And

By arbitrarily setting the thickness or the refractive index of each of the plurality of transparent substantially parallel plane portions, the focus distance when each of the plurality of transparent substantially parallel plane portions is inserted into the optical path is set. Can be changed.

According to a third aspect of the present invention, there is provided a laser projecting device including a light source for emitting a laser beam and a projecting lens for condensing the laser beam, the laser beam from the projecting lens being measured on a surface to be measured. In a laser projecting device which irradiates on and scans in one plane, it has a plurality of transparent substantially parallel plane parts having different thicknesses or refractive indexes, and one of the plurality of substantially parallel plane parts is in the optical path. Discs rotatable so as to be sequentially positioned, driving means for rotating the discs, at least two reflecting surfaces provided side by side in the scanning direction on the surface to be measured, and between the two reflecting surfaces. And a light receiving means for receiving the laser light reflected by the reflecting means and outputting an electric signal, and a reflecting means having a non-reflecting surface having a width substantially equal to the beam diameter at the focus position of the laser light. , Based on the electric signal of the light receiving means, Wherein the electrical signal that can identify the reflective surface and a focus adjustment means for controlling said drive means to be obtained.

When the disc is rotated by the driving means, one of the plurality of optical path length changing portions is sequentially positioned in the optical path, the optical path length from the light source to the light projecting lens is changed, and the focus distance is changed.

When the surface to be measured is irradiated with laser light and scanned in one plane, the laser light scans the reflecting means in the order of one of the two reflecting surfaces, the non-reflecting surface and the other of the two reflecting surfaces. When the optical path length changing portion that cannot focus the laser light on the surface to be measured is located in the optical path, the laser light having a beam diameter sufficiently larger than the width of the non-reflection surface during the scanning is applied to the non-reflection surface and Since it hits the two reflecting surfaces on both sides at the same time, an electric signal for identifying the non-reflecting surface cannot be obtained.
At this time, the focus adjusting means controls the driving means to rotate the disc.

When the optical path length changing unit capable of focusing the laser on the surface to be measured by this rotation is located in the optical path,
At the time of the scanning, the laser beam having a beam diameter substantially equal to the width of the non-reflecting surface strikes the non-reflecting surface, so that an electric signal for identifying the non-reflecting surface is obtained, and the focus adjusting means stops the rotation of the disc by the driving means.

In this way, the focus adjusting means automatically selects one of the plurality of optical path length changing parts and positions it in the optical path, so that the projection lens is not moved in the optical axis direction. It is possible to automatically adjust the focus position of the laser light applied to the surface to be measured step by step.

According to a fourth aspect of the present invention, there is provided a laser projecting apparatus, wherein a laser beam from the light source is focused on each of the plurality of substantially parallel plane parts by the lens from the projecting lens. It is characterized in that a diaphragm for narrowing down according to a focus distance to a focus position of light is provided.

Since the laser light from the light source is focused by the diaphragms provided in each of the plurality of substantially parallel plane portions located in the optical path, when each of the plurality of substantially parallel plane portions is located in the optical path, It is possible to focus the laser light within the range of the depth of field centered on the original focus distance.

According to a fifth aspect of the present invention, there is provided a laser projecting device comprising a light source for emitting a laser beam and a projecting lens for condensing the laser beam, the laser beam from the projecting lens being measured. In the laser projecting device for irradiating on the top, selectively inserted in the optical path between the light source and the projecting lens,
It is characterized by comprising a plurality of optical path length changing members for providing different optical path length changes, and continuous switching means for continuously switching the optical path length changing members inserted in the optical path.

By continuously switching the optical path length changing member selectively inserted in the optical path by the continuous switching means, the laser beam irradiated on the surface to be measured without moving the projection lens in the optical axis direction. The in-focus position of can be continuously adjusted.

According to a sixth aspect of the present invention, there is provided a laser light projecting device comprising a light source for emitting laser light and a light projecting lens for condensing the laser light, and the laser light from the light projecting lens is measured on a surface to be measured. In the laser projecting device for irradiating onto the upper surface, a plurality of transparent substantially parallel plane portions having different thicknesses or refractive indexes are provided on the circumference, and selectively in an optical path between the light source and the light projecting lens. It is characterized in that it is provided with a rotating means for rotating the inserted substantially parallel plane portion so as to be continuously switched, and a driving means for driving the rotating means at a predetermined speed.

When the rotating means is continuously rotated by the driving means, the parallel plane portions selectively inserted into the optical path are continuously switched, and the optical path length from the light source to the projection lens and the focus distance are continuously changed. To do. When the laser beam is applied to the surface to be measured, laser lines having different thicknesses substantially corresponding to the distance to the surface to be measured are continuously projected on the surface to be measured.

[0024]

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

FIG. 1 is a configuration diagram for explaining the principle of a laser projecting apparatus (visible light laser projecting apparatus) according to a first embodiment of the present invention.

As shown in FIG. 1, the laser projecting device includes a laser diode 1 for emitting a visible laser beam (hereinafter, simply referred to as a laser beam) and a projecting lens 2 for condensing the laser beam.
And a transparent glass disk 3, and is configured to irradiate the vertical wall surface 4 with the laser light from the light projecting lens 2.

As shown in FIG. 2, the glass disk 3 has six parallel plane portions (optical path length changing portions for giving different optical path length changes) 3 arranged in the circumferential direction and having different thicknesses.
It has 1 to 36. Further, the glass disk 3 is provided on the optical axis of the light projecting lens 2 so that one of the six parallel plane parts 31 to 36 is selectively inserted in the optical path between the laser diode 1 and the light projecting lens 2. It can be rotated by parallel rotating shafts 5. The thicknesses of the parallel plane portions 31 to 36 are t1 to t, respectively.
6

In FIG. 1, assuming that the focal length of the light projecting lens 2 is f, the relational expression of focus is 1 / f = (1 / a) + (1 / b). From this relational expression, the following expression (1) is obtained.

A = f · b / (b−f) Equation (1) Here, the glass disk 3 (parallel plane of the glass disk 3 is inserted in the optical path between the laser diode 1 and the light projecting lens 2). Part), the thickness is t, the apparent distance (optical path length) from the laser diode 1 to the light projection lens 2 is a, and the actual distance from the laser diode 1 to the light projection lens 2 (mechanical distance) ) Is c, the following equation (2) is obtained.

A = (ct) + (t / n) Equation (2) From Equations (1) and (2), f · b / (b−f) = (ct) + (t / n) Since the formula (3) is obtained, the focus distance (distance from the light projecting lens 2 to the focus position of the laser light focused by this lens) b can be changed by changing the thickness t.

From the equations (1) and (2), the thickness t of the parallel plane portion of the glass disk 3 is t = [(f · b / (b−f)) − c] / [(1 / n ) -1] It can be obtained by the equation (4).

Here, in order to actually determine the thicknesses t1 to t6 of the six parallel plane portions 31 to 36 of the glass disk 3 shown in FIG. 1, the focal length f of the light projecting lens 2 is f = 30 mm,
The refractive index n of the glass disk 3 is set to n = 1.5, the focus distance b is set to b = ∞ (parallel light), and the plane-parallel part 3
The thickness t1 of 1 is t1 = 4 mm. At this time, (2)
Since a = f in the formula, 30 = (ct) + (4
/1.5), and the mechanical distance c is c = 31.33 mm
You can decide (constant).

Here, five thicknesses t2 to t6 other than t1
In order to determine Eq. (4), f = 30 mm and n = 1.
5 and c = 31.33 mm are substituted, and the values of the focus distance b are 30 m, 10 m, 7 m, 5 m, and 2 m.
Are respectively substituted.

As a result, the parallel flat surface portions 31 for obtaining the six types of focus distances b shown below are obtained.
Thicknesses t1 to t6 of .about.36 are determined.

When the focus distance b = ∞, t1 = 4.00 mm When the focus distance b = 30 m, t2 = 3.90 mm When the focus distance b = 10 m, t3 = 3.72 mm When the focus distance b = 7 m, t4 = 3.60 mm, when the focus distance b = 5 m, t5 = 3.45 mm, when the focus distance b = 2 m, t6 = 2.62 mm Therefore, the glass disk 3 is rotated and the plane parallel portion 31 is rotated.
By selecting one of ~ 36 and inserting it into the optical path,
The focus position of the laser light applied to the wall surface 4 can be adjusted stepwise. That is, it is possible to perform multi-stage focusing (six stages of focusing).

FIG. 3 shows a laser projection device according to the first embodiment using the principle shown in FIG. Note that FIG.
In the description of 1., the same members as those in FIG. 1 are denoted by the same reference numerals, and duplicate description will be omitted.

At the lower end of the main body 6 of the laser projector shown in FIG. 3, three leveling screws 7 for leveling are provided. The laser diode 1 is provided above the base portion 6 a of the main body 6. A light projecting lens 2 is fixed to the main body 6 and arranged above the laser diode 1. Above the light projecting lens 2, the vertical laser light from the light projecting lens 2 is deviated in the horizontal direction and at the same time 360 °.
A rotating unit 10 for scanning in the direction is provided. The rotation unit 10 has a penta mirror 11, and is supported by the main body 6 via a bearing 12 so as to be rotatable about the vertical direction. The rotation of the motor 13 is transmitted to the rotation unit 10 via the transmission belt 14.

The glass disk 3 can be rotated by a pulse motor 8. By operating the pulse motor 8 with a remote controller or the like, the six parallel plane portions 31 to
One of the reference numerals 36 is designed to be selectively inserted in the optical path between the laser diode 1 and the light projecting lens 2.

In the first embodiment, the plane parallel units 31 to 36 are controlled by the pulse motor 8 and the remote controller for operating the same.
The focus adjusting means is configured to insert one of them into the optical path.

Next, the operation of the first embodiment shown in FIG. 3 will be described.

When performing a measuring operation in the horizontal direction by using such a laser projecting device, first, the laser projecting device is installed and leveling is performed by the three leveling screws 7. Body 6
Is provided with two rod-shaped bubble tubes (not shown) in the directions of two axes orthogonal to each other, and the leveling is performed while observing these bubble tubes.

In the state where the leveling is completed, the laser light 20A emitted from the laser diode 1 in the vertical direction passes through the light projecting lens 2 and is then deviated in the horizontal direction by the pentamirror 11 to make it transparent glass for waterproofing. Through 15. The transmitted horizontal laser light 20B is scanned in the 360 ° direction by the rotation of the rotary unit 10. Laser light 20
B is irradiated on the vertical wall surface 4 to form a horizontal surface on the wall surface 4.

Now, for example, the wall surface 4 is a distance (projecting lens 2
At an optical distance of 5 m and a thickness t2 (t2
= 3.90 mm) and the plane parallel part 3 of the glass disk 3
2 is located in the light path. At this time, the operator operates the remote controller or the like to rotate the pulse motor 8 so that the beam diameter of the laser beam 20B is minimized while looking at the laser beam 20B irradiated on the wall surface 4. By this rotation, when the parallel flat surface portion 35 of the glass disk 3 having the thickness t5 (t5 = 3.45 mm) is located in the optical path,
The beam diameter of the laser light 20B with which the wall surface 4 is irradiated becomes the smallest, and the focus position of the laser light 20B coincides with the wall surface 4.

Further, for example, it is assumed that the wall surface 4 is located at a distance of 10 m, and the parallel flat surface portion 32 of the glass disk 3 having a thickness t2 (t2 = 3.90 mm) is located in the optical path. Also at this time, the operator operates the remote controller or the like to rotate the pulse motor 8 so that the beam diameter of the laser beam 20B is minimized. By this rotation, the thickness t3
When the parallel plane portion 33 of the glass disk 3 having (t3 = 3.72 mm) is located in the optical path, the beam diameter of the laser light 20B becomes the smallest and the focused position of the laser light 20B coincides with the wall surface 4.

As described above, according to the first embodiment, the glass disk 3 is rotated by operating the remote controller or the like so that the beam diameter of the laser beam 20B irradiated on the wall surface 4 is minimized while observing the laser beam 20B. Let parallel plane parts 31 to 36
Just select one of them and insert it into the optical path.
The in-focus position of 0B can be adjusted in stages (focusing in 6 steps). Therefore, the focus position of the laser light can be adjusted stepwise without moving the light projecting lens 2 in the optical axis direction. Therefore, it is possible to focus the laser light with high work efficiency while simplifying the structure and reducing the manufacturing cost.

Next, a modification of the first embodiment will be described.

In the modification of the first embodiment, the pulse motor 8 constitutes continuous switching means for continuously switching the parallel plane portions 31 to 36 inserted in the optical path.

Next, the operation of the modified example will be described with reference to FIG.

For example, when performing a horizontal measuring operation using such a laser light projecting device, first, as in the first embodiment, the laser light projecting device is first installed and leveled by the three leveling screws 7. Do. Two rod-shaped bubble tubes (not shown) are provided in the main body 6 in the directions of two axes orthogonal to each other, and the leveling is performed while observing these bubble tubes.

After the leveling is completed, the laser light 20A emitted from the laser diode 1 in the vertical direction passes through the light projecting lens 2 and is then deflected in the horizontal direction by the pentamirror 11 to be transparent glass for waterproofing. Through 15.

At this time, since the parallel plane portions 31 to 36 are successively inserted into the optical path by the continuous rotation of the pulse motor 8, the light passing through the light projecting lens 2 continuously focuses.

The horizontal laser beam 20B that has passed through
Is scanned in the 360 ° direction by the rotation of the rotary unit 10. The laser beam 20B is irradiated on the vertical wall surface 4, and a laser line (horizontal plane) is projected on the wall surface 4.

Now, for example, the wall surface 4 is at a distance (projecting lens 2
(Optical distance from) 5 m.

When the parallel flat surface portion 35 of the glass disk 3 having the thickness t5 (t5 = 3.45 mm) is inserted into the optical path, the laser line irradiated on the wall surface 4 is the finest and clearest (laser light 20B). Beam diameter becomes the smallest), and when the other parallel plane portions 31 to 34 and the parallel plane portion 36 are inserted in the optical path, the laser line becomes thick and unclear as the focus distance increases ( The beam diameter of the laser beam 20B is large).

That is, a laser line that changes sharply from the blur and continuously changes from the clear to the blur is projected on the wall surface as the motor 8 rotates.

The rotation speed of the pulse motor 8 is set sufficiently slower than the horizontal scanning speed of the laser beam 20B.

As described above, according to this modification,
Since the focus operation is performed continuously, a thin and clear laser line corresponding to almost the distance is projected on the surface to be measured in a short time, but the operator can easily identify the difference in the thickness of the laser line. The installation work can be speeded up, and since the remote controller is not required, the structure is simplified and the manufacturing cost can be reduced more than that of the first embodiment.

FIG. 4 is a block diagram for explaining the principle of the laser projection apparatus according to the second embodiment of the present invention.

This laser projecting device is provided with an automatic inclination correcting device. That is, the laser light projecting apparatus shown in FIG. 4 has a laser diode 1, a collimator lens 41 for collimating the laser light from the laser diode 1, and a silicon having a free liquid surface C1 arranged above the collimator lens 41. Between the transparent container 42 in which the oil C is enclosed, the Keplerian telescope 43 for expanding the inclination of the light (refracted light) L1 refracted by the silicone oil C, and the two convex lenses 43A and 43B constituting the Keplerian telescope 43. And a transparent glass plate 30 arranged.

The glass plate 30 has three parallel plane portions (optical path length changing portions) 301 to 303 having mutually different thicknesses. Further, the glass plate 30 has three parallel plane portions 301-.
One of the lenses 303 is selectively inserted into the optical path between the laser diode 1 and the projection lens 2 so that the convex lens 43B
It is movable in the direction perpendicular to the optical axis of. Parallel plane part 30
The thickness of 1 to 30 3 is t1 to t3, respectively.

In the laser projecting device shown in FIG. 4, the laser light L from the laser diode 1 is collimated by the collimator lens 41 and enters the transparent container 42. If the entire device is tilted by an angle θ1, the silicone oil C in the transparent container 42
Since the free liquid surface C1 of C is kept horizontal, the silicone oil C becomes a liquid wedge prism having a gradient angle θ1. The laser light L1 that has passed through the silicon oil C is refracted and becomes a laser light L1 having an inclination of an angle θ2 = (n−1) · θ1 [approximate expression] and enters the Keplerian telescope 43.
Here, n is the refractive index of the silicone oil C.

The laser beam L1 having the inclination of θ2 is the focal length f of the incident side convex lens 43A of the Keplerian telescope 43.
2 and the magnification by the focal length f3 of the exit side convex lens 43B, the laser beam L2 having an angle .theta.3 represented by the following equation.
And the light is emitted vertically upward.

Θ3 = θ2f2 / f3 That is, the automatic tilt-corrected angle θ3 is obtained by the following equation.

Θ3 = [(n-1) θ1] f2 / f3 From this equation, the tilt angle θ1 of the entire apparatus and the angle θ3 to be corrected must be equal, so f2 / f3 = 1
A conditional expression for tilt correction of / (n-1) is derived.

In other words, the silicone oil C can be freely selected in consideration of damping of vibrations generated in the device, such as viscosity, and the Keplerian telescope can be selected according to the refractive index n of the selected silicone oil C. Magnification of 43 (f2 / f3
) Should be set.

As described above, in the laser projecting device shown in FIG. 4, the laser beam L2 emitted from the emitting side convex lens (projecting lens) 43B is always in the vertical direction even if the entire device is inclined by θ1.

In the laser projector shown in FIG. 4, the focal length f3 of the convex lens 43B is f3 = 20 mm, the refractive index n of the glass plate 30 is n = 1.5, and the thickness of the parallel flat surface portion 303 of the glass plate 30 is set. Focus distance b at t3 = 3 mm
Is set to ∞, from the above equation (2), the secondary light source L0
The mechanical distance c from ′ to the convex lens (projecting lens) 43B can be determined as c = 21 mm (constant). In FIG. 4, reference numeral L0 indicates the position of the primary light source,
The secondary light source L0 'is conjugate with the primary light source L0.

Here, two thicknesses t1 and t other than t3
In order to determine 2, in the above formula (4), f = 20 mm, n
= 1.5 and c = 21 mm are substituted, and 20 m and 5 m are substituted as the value of the focus distance b.

As a result, the parallel plane portions 30 for obtaining the three types of focus distances b shown below, respectively.
Thicknesses t1 to t3 of 1 to 303 are determined.

When the focus distance b = ∞, t3 = 3.00 mm When the focus distance b = 20 m, t2 = 2.94 mm When the focus distance b = 5 m, t1 = 2.76 mm Therefore, the glass plate 30 is used as the optical axis. It is possible to adjust the focus position of the laser beam irradiated on the wall surface 4 stepwise by moving the laser beam irradiating the wall surface 4 by moving it in the direction perpendicular to the direction and selecting one of the parallel plane portions 301 to 303 and inserting it into the optical path. . That is,
It is possible to perform multi-stage focusing (focusing in three steps).

FIG. 5 shows a laser projection device according to the second embodiment using the principle shown in FIG. Note that FIG.
3, the same members as those in FIG. 3 are designated by the same reference numerals, and the duplicated description will be omitted.

In the laser projecting device shown in FIG. 5, the glass plate 30 is moved in a direction perpendicular to the optical axis so that the parallel flat surface portion 3 is formed.
An operation member 45 for selecting one of 01 to 303 and inserting it into the optical path is provided. One end of the operating member 45 is fixed to the end portion of the glass plate 30 by adhesion or the like, and the other end projects outside the main body 6.

In the second embodiment, the focus adjusting means is composed of the operating member 45.

Next, the operation of the second embodiment shown in FIG. 5 will be described.

For example, when performing a horizontal measurement work, the leveling as described above is first performed.

With the leveling completed, for example, the wall surface 4 is located at a distance of 5 m, and the parallel plane portion 302 of the glass plate 30 having the thickness t2 (t2 = 2.94 mm) is located in the optical path. And At this time, the operator operates the operation member 45 while watching the laser light 20B irradiated on the wall surface 4 so that the beam diameter of the laser light 20B becomes the smallest, and the glass plate 30 is directed in a direction perpendicular to the optical axis. Move to.

By this movement, the thickness t1 (t1 = 2.7
When the plane-parallel portion 301 of the glass plate 30 having a diameter of 6 mm is located in the optical path, the laser beam 20B irradiated on the wall surface 4
Has the smallest beam diameter, and the focus position of the laser light 20B coincides with the wall surface 4.

Further, for example, it is assumed that the wall surface 4 is located at a distance of 20 m, and the parallel flat surface portion 303 of the glass plate 30 having a thickness t3 (t3 = 3.0 mm) is located in the optical path. Also at this time, the operator operates the operation member 45 to move the glass plate 30 in the direction perpendicular to the optical axis so that the beam diameter of the laser light 20B becomes the smallest. By this movement, when the parallel flat surface portion 302 of the glass plate 30 having the thickness t2 (t2 = 2.94 mm) is positioned in the optical path, the beam diameter of the laser light 20B becomes the smallest and the laser light 20
The in-focus position of B coincides with the wall surface 4.

As described above, according to the second embodiment, the glass plate 30 is moved by the operating member 45 while observing the laser beam 20B irradiated on the wall surface 4 so that the beam diameter becomes the smallest. By selecting one of the parallel plane portions 30 1 to 30 3 and inserting it into the optical path, the laser beam 20
The focus position of B can be adjusted stepwise. That is, it is possible to perform focusing in three stages of a short distance (within 5 m), a medium distance (around 20 m), and a long distance (up to ∞).

Therefore, it is possible to focus the laser light with high work efficiency while simplifying the structure and reducing the manufacturing cost.

Next, a laser projection device according to a third embodiment of the present invention will be described with reference to FIGS. In the description of this embodiment, the same members as those in FIG. 3 are designated by the same reference numerals, and the duplicated description will be omitted.

This laser projecting device is provided with the vertical wall surface 4
The focus position of the laser beam 20B radiated (see FIG. 3) can be automatically adjusted stepwise (in three steps).

Therefore, in the laser projection apparatus according to the third embodiment, three parallel plane portions 311 to 311 having different thicknesses are used.
A transparent glass disc 31 having 313, and a glass disc 3
1, a pulse motor 8 for rotating 1; a beam splitter 50 provided above the light projecting lens 2; a reflective target 60 provided on the wall surface 4; and a laser beam reflected by the reflective target 60 for beam splitter 50 and a condenser. Light receiving element 7 that outputs an electric signal received through the lens 51
0, and a focus adjustment unit 80 (see FIG. 10) that controls the pulse motor 8 based on the electric signal of the light receiving element 70.

The glass disk 31 has a structure shown in FIGS. 6, 8 and 9.
As shown in FIG.
313 is formed by dividing into three strips. The thicknesses t1, t2, and t3 of the parallel plane portions 311 to 313 are set so that the focus distance b is 5 m, 20 m, and 40 m, respectively. One surface of the glass disk 31 is a light shielding surface. Circular diaphragms 91 to 93 for narrowing the laser light 20A from the laser diode 1 according to the focus distance b are provided on the parallel plane portions 311 to 313. Circular diaphragms 92 are provided at two locations on the parallel plane portion 312. When the glass disk 31 is driven by the pulse motor 8 and rotated clockwise by 90 ° in FIG. 8,
The diaphragm 93 of the parallel plane portion 313, the diaphragm 92 of the parallel plane portion 312, the diaphragm 91 of the parallel plane portion 311, and the parallel plane portion 3
The 12 diaphragms 92 are arranged so as to be sequentially positioned in the optical path. Further, the glass disk 31 has four diaphragms 91,
Rectangular light transmitting portions 91a, 9a are provided on the outer sides of 92, 92, 93.
2a, 92b, 93a are provided respectively. These four light transmitting portions 91a, 92a, 92b, 93a are
They are arranged at positions deviated by 90 ° in the circumferential direction.

As shown in FIG. 7, the reflective target 60
Is a resin thin plate 61, three reflecting surfaces 62 to 64 provided on the thin plate 61, and two non-reflecting surfaces 6 respectively.
It is composed of 5, 66.

The three reflecting surfaces 62 to 64 are strip-shaped surfaces having substantially the same dimensions, and the longitudinal direction of each is perpendicular to the scanning direction of the laser light 20B with which the wall surface 4 is irradiated (the left-right direction in FIG. 7). Are provided side by side in the scanning direction. The width of each of the reflecting surfaces 62 to 64 is the laser light 20B.
Has a width equal to or larger than the beam diameter D when irradiated with parallel light.

The non-reflective surface 65 is an elongated strip-shaped surface provided between the reflective surfaces 62 and 63, and has a width substantially equal to the beam diameter (minimum beam diameter) d at the focus position of the laser beam 20B. In this specification, "a width approximately equal to the beam diameter (minimum beam diameter) d at the focus position of the laser beam 20B" is used to include a width up to about 1.5 times the minimum beam diameter d. are doing. The non-reflecting surface 66 is a strip-shaped surface provided between the reflecting surfaces 63 and 64 and has a width of about 3 times the minimum beam diameter d.

Further, in the center of the reflective target 60,
Reference line 67 for adjusting to the scanning direction of the laser beam 20B
And a V groove 68 for marking.
Are provided on both sides of the reference line 67.

Further, the focus adjusting section 80 converts the electric signal (analog signal shown in FIGS. 11A to 11C) output from the light receiving element 70 into a digital signal shown in FIGS. 12A to 12C. An operational amplifier 81 for converting each, a counter 82 for counting the number of digital signals output from the operational amplifier 81, and four light transmission parts 9 of the glass disk 31.
1a, 92a, 93a, 92b are detected to detect the glass disk 3
It has a photo interrupter 83 that detects 90 ° rotation of 1 and outputs an ON or OFF signal at the time of detection, and a motor control unit 84 that controls the pulse motor 8.

In the operational amplifier 81, the voltage value of the electric signal (analog signal) output from the light receiving element 70 becomes equal to or higher than a predetermined voltage value (electrical slice level) S and then becomes equal to or lower than the predetermined voltage value S. It is sometimes configured to output one digital signal.

The motor control unit 84 rotates the pulse motor 8 by 90 ° by the output of the photo interrupter 83 until the count value of the counter 82 becomes 3, and the counter 82 is rotated.
When the count value of 3 becomes 3, the pulse motor 83 is stopped.

Next, the operation of the third embodiment having the above configuration will be described.

For example, when performing a horizontal measurement operation, the above-described leveling is first performed.

With the leveling completed, for example, the wall surface 4 is located at a distance of 5 m, and the parallel flat surface portion 313 of the glass plate 31 having the thickness t3 set for the focus distance of 40 m is located in the optical path. Suppose

At this time, the laser light 20A from the laser diode 1 is emitted from the diaphragm 9 of the parallel plane portion 313 in the optical path.
The laser beam 20B is narrowed by 3 and transmitted through the parallel flat surface portion 31 3, and becomes horizontal laser light 20B through the light projecting lens 2, the beam splitter 50 and the penta mirror 11, and is irradiated onto the wall surface 4.
The wall surface 4 is scanned in the horizontal direction. Thereby, the reflection target 60 in which the laser beam 20B is provided on the wall surface 4
The top is scanned, for example, from left to right in FIG.

At this time, the laser light 20 irradiated on the wall surface 4
Since the focus distance of B is 40 m and the focus position is largely deviated from the wall surface 4, a laser beam having a thick beam diameter as shown by reference numeral 70a in FIG.
Scan the top from left to right in FIG. Reflective target 60
The laser beam 20B reflected by the laser beam enters the beam splitter 50 through the pentamirror 11 in the opposite direction to the outward path, is reflected by the beam splitter 50, and then the condenser lens 5
The light is received by the light receiving element 70 via 1.

At this time, the electric signal output from the light receiving element 70 becomes an analog signal as shown in FIG. That is, this analog signal becomes a high level (A1 portion) when the laser beam 70a having a large beam diameter shown in FIG. 7 hits the reflecting surface 62 during the scanning, and the laser beam 70a is applied to the non-reflecting surface 65 and both sides thereof. Some reflective surface 6
When it hits 2 and 63 at the same time, the level is slightly lower than the A1 part (A2 part), and the laser beam 70a is reflected by the reflecting surface 6
When the laser beam 70a hits the laser beam 70a on the non-reflective surface 66 and the reflecting surfaces 63 and 64 on both sides of the non-reflecting surface 66 at the same time, the laser beam 70a has a level lower than the A2 portion (A4 section), and the laser It is shown that when the light 70a hits the reflecting surface 64, it becomes a high level (A5 portion). A of the analog signal shown in FIG.
The second part does not fall below the slice level S, that is, this analog signal does not include an electrical signal that can identify the non-reflective surface 65.

At this time, the operational amplifier 81 outputs the analog signal as shown in FIG. 11A, which does not include the signal having the slice level S or lower, from the light receiving element 70, so that it is shown in FIG. 12A. It outputs one such digital signal.

The counter 82 counts one digital signal output from the operational amplifier 81 and outputs a signal representing the count value 1 to the motor control unit 84. by this,
The motor control unit 84 gives a drive command to the pulse motor 8,
The pulse motor 8 rotates the glass disc 31.

When the glass disk 31 is rotated by 90 ° (rotated by 90 ° in the clockwise direction in FIG. 8) so that the plane parallel portion 312 is located in the optical path and the light transmitting portion 92a is detected by the photo interrupter 83, The interrupter 83 outputs, for example, an ON signal to the motor control unit 84. In response to this ON signal, the motor control unit 84 outputs a stop command to the pulse motor 8,
The glass disc 31 stops.

At this time, the laser light 20A from the laser diode 1 is transmitted through the diaphragm 9 of the parallel plane portion 312 in the optical path.
After being narrowed down by 2 and transmitted through the parallel flat surface portion 312, a horizontal laser beam 20B is formed in the same manner as above to scan the wall surface 4 and the reflection target 60.

At this time, the laser light 20 irradiated on the wall surface 4
The focus distance of B is 20 m, and the focus position is on the wall surface 4.
Since it is out of alignment, the laser beam 70b having a slightly larger beam diameter as shown by reference numeral 70b in FIG. 7 scans the wall surface 4 and the reflection target 60.

At this time, the electric signal output from the light receiving element 70 becomes an analog signal as shown in FIG. 11 (b). The B1 to B5 parts of this analog signal are shown in FIG.
It corresponds to the A1 to A5 parts of the analog signal shown in FIG. In the analog signal shown in FIG. 11B, since the beam diameter of the laser beam 70b is substantially the same as the width of the non-reflecting surface 66, the B4 portion is below the slice level S. However, the B2 portion is not below the slice level S.
That is, the analog signal shown in FIG.
Like the analog signal in (a), it does not include an electrical signal that can identify the non-reflective surface 65.

As shown in FIG. 11B, when an analog signal once below the slice level S is input in the B4 section, the operational amplifier 81 outputs two digital signals as shown in FIG. 12B. To do.

The counter 82 counts the two digital signals output from the operational amplifier 81 and outputs a signal representing the count value 2 to the motor controller 84. by this,
The motor control unit 84 gives a drive command to the pulse motor 8 again, and the pulse motor 8 rotates the glass disk 31.

When the glass disk 31 is further rotated 90 ° so that the parallel flat surface portion 311 is located in the optical path and the light transmitting portion 91a is detected by the photo interrupter 83, the photo interrupter 83 sends an ON signal to the motor control portion 84. Output to. In response to this ON signal, the motor control unit 84 outputs a stop command to the pulse motor 8 and the glass disk 31 stops.

At this time, the laser light 20A from the laser diode 1 is transmitted through the diaphragm 9 of the parallel plane portion 311 in the optical path.
After being narrowed down by 1 and transmitted through the parallel flat surface 311, the horizontal laser beam 20B is made to scan on the wall surface 4 and the reflection target 60 in the same manner as described above.

At this time, the laser light 20 irradiated on the wall surface 4
Since the focus distance of B is 5 m, and the focus position thereof coincides with the wall surface 4, the laser beam 70c having the minimum beam diameter as shown by reference numeral 70c in FIG.
Scan above.

At this time, the electric signal output from the light receiving element 70 becomes an analog signal as shown in FIG. 11 (c). The C1 to C5 parts of this analog signal are shown in FIG.
It corresponds to the A1 to A5 parts of the analog signal shown in FIG. In the analog signal shown in FIG. 11C, since the beam diameter of the laser beam 70c is substantially the same as the width of the non-reflecting surface 65, the C2 portion and C4 are below the slice level S. That is, the analog signal shown in FIG. 11C includes an electric signal (C2 portion) that can identify the non-reflective surface 65.

When the analog signal shown in FIG. 11 (c) is input, the operational amplifier 81 outputs three digital signals as shown in FIG. 12 (c).

The counter 82 counts the three digital signals output from the operational amplifier 81 and outputs a signal representing the count value 3 to the motor control unit 84. by this,
The control by the motor control unit 84 for automatically adjusting the focus position of the laser beam 20B irradiated on the wall surface ends.

As is apparent from the above description, when the wall surface 4 is located at the distance of 20 m, the glass disk 31 is rotated by the pulse motor 8 to have the thickness t2 set for the focus distance of 20 m. When the plane parallel portion 312 is located in the optical path (when the diaphragm 92 is located in the optical path)
In addition, the laser beam 70c having the minimum beam diameter shown in FIG.
And scan over the reflective target 60. At this time, FIG.
Three digital signals as shown in 2 (c) are output from the operational amplifier 81, and the control by the motor control unit 84 for automatically adjusting the focus position of the laser beam 20B ends.

Similarly, when the wall surface 4 is located at a distance of 40 m, the glass disk 31 is rotated by the pulse motor 8 and the thickness t3 set for the focus distance of 40 m is set.
When the plane parallel part 313 having is located in the optical path,
The laser beam 70c having the minimum beam diameter shown in FIG. 7 scans the wall surface 4 and the reflection target 60. At this time, FIG.
Three digital signals as shown in (c) are operational amplifier 8
1 is output and the control by the motor control unit 84 for automatically adjusting the focus position of the laser beam 20B ends.

As described above, according to the third embodiment, by automatically selecting one of the parallel flat surface portions 311 to 313 of the glass disk 31 and positioning it in the optical path,
It is possible to automatically adjust the focus position of the laser light with which the wall surface 4 is irradiated stepwise without moving the light projecting lens 2 in the optical axis direction.

Further, according to the third embodiment, the laser light 20A from the laser diode 1 is emitted from the glass disc 3
When the parallel flat surface portion 311 is located in the optical path, the diaphragm 91 is used. When the parallel flat surface portion 312 is located in the optical path, one of the two diaphragms 92 is used. When the parallel flat surface portion 331 is located in the optical path, the diaphragm 93 is used. Each is squeezed and passes through each parallel plane portion. That is, the laser light 20A
Is narrowed down by the diaphragms 91 to 93 having a size corresponding to the focus distance. Therefore, when each of the parallel plane portions 311 to 313 is located in the optical path, not only the focus distance corresponding to the parallel plane portion in the optical path, but also within the range of the depth of field centered on this focus distance. The laser light can be focused.

For example, not only when the wall surface 4 is located at the distance 40 m when the plane parallel part 313 having the thickness t3 set for the focus distance 40 m is located in the optical path, the wall surface 4 is located at the distance 40 m. Even when the depth of field is centered around, the same effect as that obtained by focusing the laser light irradiating the wall surface 4 at a level without causing any actual damage can be obtained.

Therefore, according to the third embodiment, by selecting one of the three parallel plane portions 311 to 313 and positioning it in the optical path, the wall surface 4 is formed over substantially the entire area from the closest distance to about 50 m. It is possible to focus the laser light applied to the.

Further, according to the third embodiment, since the reflection target 60 is provided with the non-reflection surface 66 and the reflection surface 64, the laser reflected by the reflection target 60 and received by the light receiving element 70 is received. The light can be distinguished from the light (noise) reflected by a member other than the reflective target 60 and received by the light receiving element 70.

In each of the above-described embodiments, the different parallel plane portions have different thicknesses, but when the plurality of parallel plane portions have the same thickness and the respective refractive indexes are different. Also has the same effect.

Further, in each of the above embodiments, the number of the plurality of parallel plane portions can be arbitrarily changed.

Further, in the description of the operation of each of the above-mentioned embodiments, only the case where the horizontal surveying work is performed has been described. However, the laser projecting device according to the present invention is not limited to that work, and the vertical surveying work is performed. It can also be applied to general surveying work.

[0122]

As described above, according to the laser projector of the first aspect of the invention, the focus adjusting means selects one of the plurality of optical path length changing parts and inserts it into the optical path. As a result, the focus position of the laser light with which the surface to be measured is irradiated can be adjusted stepwise without moving the projection lens in the optical axis direction. Therefore, it is possible to focus the laser light with high work efficiency while simplifying the structure and reducing the cost.

According to the laser projecting device of the second aspect of the present invention, by setting the thickness or the refractive index of each of the plurality of transparent substantially parallel plane portions to any plurality of transparent substantially parallel plane surfaces. The focus distance can be changed when each of the parts is inserted into the optical path.

According to the laser projecting apparatus of the third aspect of the invention, the focus adjusting means automatically selects one of the plurality of optical path length changing parts and positions it in the optical path, thereby projecting light. It is possible to automatically adjust the focus position of the laser light applied to the surface to be measured stepwise without moving the lens in the optical axis direction.

According to the laser projecting device of the fourth aspect of the invention, the laser light can be focused within the range of the depth of field with the original focus distance as the center, and the laser light can be covered in a wide range. Can be focused over.

According to the laser projecting device of the fifth and sixth aspects of the invention, the focusing operation is continuously performed,
A thin and clear laser line corresponding to almost the distance is projected on the surface to be measured in a short time. Since the operator can easily identify the difference in the thickness of the laser line, it is possible to speed up the measurement work. Further, since the remote controller is not required, the structure is simple and the manufacturing cost can be further reduced.

[Brief description of drawings]

FIG. 1 is a schematic configuration diagram for explaining the principle of a laser projection device according to a first embodiment of the present invention.

FIG. 2 is a plan view showing a glass disc used in the laser projecting device of FIG.

FIG. 3 is a vertical sectional view showing a laser projection device according to a first embodiment of the present invention.

FIG. 4 is a schematic configuration diagram for explaining the principle of a laser projection device according to a second embodiment of the present invention.

FIG. 5 is a vertical sectional view showing a laser projection device according to a second embodiment of the present invention.

FIG. 6 is a vertical sectional view showing a laser projection device according to a third embodiment of the present invention.

7 is a plan view showing a reflection target used in the laser projecting device of FIG.

FIG. 8 is a plan view showing a glass disk used in the laser projection device of FIG.

9 is a cross-sectional view showing the positional relationship between the glass disc and the photo interrupter of FIG.

FIG. 10 is a block diagram showing a focus adjustment unit used in the laser projection device of FIG.

11 is a waveform diagram showing an output signal of a light receiving element used in the laser projector of FIG.

12 is a waveform diagram showing an output signal of the operational amplifier shown in FIG.

FIG. 13 is a vertical cross-sectional view showing a conventional laser light projecting device.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 laser diode (light source) 2 light projecting lens 4 wall surface (measurement surface) 8 pulse motor (driving means) 31 to 36, 301 to 303, 311 to 313 parallel plane portion (optical path length changing portion) 31 glass disk (circle) Plate 43B Ejection-side convex lens (projecting lens) 45 Operation member (focus adjusting means) 60 Reflective target (reflecting means) 62, 63 Reflective surface 65 Non-reflective surface 70 Light receiving element (light receiving means) 80 Focus adjusting section (focus adjusting means) ) L0 'Secondary light source (light source)

Claims (6)

[Claims] 1. A laser projecting device comprising: a light source for emitting a laser beam; and a projecting lens for condensing the laser beam, wherein the laser beam from the projecting lens is applied to a surface to be measured. A plurality of optical path length changing units selectively inserted in the optical path between the light projecting lens and the optical path length changing unit, and selecting one of the plurality of optical path length changing units in the optical path. And a focus adjusting means to be inserted in the laser projecting device. 2. The laser light projecting device according to claim 1, wherein the plurality of optical path length changing portions are respectively formed of a plurality of transparent substantially parallel plane portions having different thicknesses or refractive indexes. 3. A laser comprising a light source for emitting laser light and a light projecting lens for condensing the laser light, irradiating the laser light from the light projecting lens onto a surface to be measured, and scanning in one plane. In the light projecting device, a disc having a plurality of transparent substantially parallel plane portions having different thicknesses or refractive indices, and a rotatable disc such that one of the plurality of substantially parallel plane portions is sequentially positioned in the optical path, Driving means for rotating the disk, at least two reflecting surfaces provided side by side in the scanning direction on the surface to be measured, and provided between the two reflecting surfaces at a focus position of the laser beam. A reflecting means having a non-reflecting surface having a width substantially equal to the beam diameter, a light receiving means for receiving an electric signal to receive the laser beam reflected by the reflecting means, and an electric signal of the light receiving means,
A laser projecting device comprising: a focus adjusting unit that controls the driving unit until an electric signal that can identify the non-reflective surface is obtained. 4. The laser light from the light source is supplied to each of the plurality of substantially parallel plane portions in accordance with a focus distance from the light projecting lens to a focus position of the laser light focused by the lens. The laser projection device according to claim 2 or 3, further comprising a diaphragm for squeezing. 5. A laser projecting device comprising a light source for emitting laser light and a light projecting lens for condensing the laser light, and irradiating the surface to be measured with the laser light from the light projecting lens. A plurality of optical path length changing members that are selectively inserted in the optical path between the light projecting lens and the light projecting lens to give different optical path length changes, and the optical path length changing member that is inserted in the optical path. A laser projecting device comprising: continuous switching means for switching. 6. A laser projecting device comprising: a light source for emitting laser light; and a projecting lens for condensing the laser beam, wherein the laser light from the projecting lens is irradiated onto a surface to be measured. Or, it has a plurality of transparent substantially parallel plane portions having different refractive indexes on the circumference, and the substantially parallel plane portions that are selectively inserted in the optical path between the light source and the light projecting lens are continuous. A laser projecting device comprising: a rotating unit that rotates so as to switch; and a driving unit that drives the rotating unit at a predetermined speed.