阅读说明：本技术 测量装置 (Measuring device ) 是由 吉野健一郎 江野泰造 森田英树 藤田倖平 于 2019-08-02 设计创作，主要内容包括：本发明具备将直线偏振光的测距光向测定对象物照射的投光光学系统、接受来自前述测定对象物的反射测距光的受光光学系统、选择由该受光光学系统受光的前述反射测距光的偏振光的偏振光选择部、基于前述反射测距光的受光结果控制距离测定的计算控制部,该计算控制部构成为,基于由于前述偏振光选择部的偏振光的选择产生的受光量的变化,对前述测定对象物的测距结果赋予材质信息。(The present invention is provided with a light projecting optical system for irradiating a measurement target object with linear polarized distance measuring light, a light receiving optical system for receiving reflected distance measuring light from the measurement target object, a polarized light selecting unit for selecting the polarized light of the reflected distance measuring light received by the light receiving optical system, and a calculation control unit for controlling distance measurement based on the light receiving result of the reflected distance measuring light, wherein the calculation control unit is configured to give material information to the measurement result of the measurement target object based on a change in the amount of light received due to the selection of the polarized light by the polarized light selecting unit.)

1. A measuring device is characterized in that a measuring device is provided,

the measuring device comprises a light projecting optical system, a light receiving optical system, a polarized light selecting unit, a bracket unit, a scanning mirror, a horizontal angle detecting unit, a vertical angle detecting unit, and a calculation control unit,

the light projecting optical system irradiates the linearly polarized ranging light to the object to be measured,

the light receiving optical system receives the reflected distance measuring light from the object to be measured,

the polarized light selecting unit selects the polarized light of the reflected distance measuring light received by the light receiving optical system,

the bracket part horizontally rotates around a horizontal rotating shaft by a horizontal rotating motor,

the scanning mirror is provided on the carriage portion and vertically rotates around a vertical rotation axis by a vertical rotation motor to irradiate the distance measuring light from the light projecting optical system to the measurement object and to cause the reflected distance measuring light from the measurement object to enter the light receiving optical system,

the horizontal angle detecting part detects the horizontal angle of the bracket part,

the vertical angle detecting section detects a vertical angle of the scanning mirror,

the calculation control unit controls distance measurement, rotation of the holder unit, and rotation of the scanning mirror based on the result of reception of the reflected distance measuring light,

the calculation control unit is configured to give material information to a distance measurement result of the measurement object based on a change in the amount of received light caused by selection of the polarized light by the polarized light selection unit.

2. The measuring device of claim 1,

the polarization beam selector is a polarization beam splitter for separating the reflected distance measuring beam into P-polarized light and S-polarized light,

the light receiving optical system includes a 1 st light receiving unit disposed on a transmission optical axis of the polarization beam splitter, a 2 nd light receiving unit disposed on a reflection optical axis of the polarization beam splitter,

the calculation control unit compares the amount of light received by the 1 st light receiving unit with the amount of light received by the 2 nd light receiving unit.

3. The measuring device of claim 2,

the device further comprises an 1/4 wavelength plate disposed on a common optical path of the distance measuring light and the reflected distance measuring light.

4. The measuring device of claim 2,

the optical system further includes 1/4 wavelength plates respectively disposed on the optical axis of the distance measuring light and the optical axis of the reflected distance measuring light.

5. The measuring device of claim 1,

the polarized light selecting part is composed of a polarized light plate which can be inserted and separated and is arranged on the optical axis of the reflected distance measuring light, and a polarized light plate driving part which enables the polarized light plate to be inserted and separated,

the calculation control unit compares the amount of light received by the reflected distance measuring light transmitted through the polarizer and received by the light receiving optical system with the amount of light received by the reflected distance measuring light not transmitted through the polarizer and received by the light receiving optical system.

6. The measuring device of claim 1,

the polarization beam selector is a polarization beam splitter for separating the distance measuring beam into P-polarized light and S-polarized light,

the light projection optical system comprises a 1 st light source unit disposed on the transmission optical axis of the polarization beam splitter to emit the distance measuring light of the linear polarization light, a 2 nd light source unit disposed on the reflection optical axis of the polarization beam splitter to emit the distance measuring light of the linear polarization light orthogonal to the linear polarization light, and a polarization plate disposed on the optical axis of the reflection distance measuring light,

the calculation control unit compares the light receiving amounts of the distance measuring lights emitted from the 1 st light source unit and the 2 nd light source unit and detected by the light receiving optical system.

7. The measuring device of claim 1,

the polarized light selecting unit comprises an 1/2 wavelength plate disposed on the optical axis of the distance measuring light so as to be insertable and detachable, a wavelength plate driving unit for inserting and detaching the 1/2 wavelength plate, and a polarizing plate disposed on the optical axis of the reflected distance measuring light,

the calculation control unit compares the amount of light received by the reflected distance measuring light transmitted through the 1/2 wavelength plate and received by the light receiving optical system with the amount of light received by the reflected distance measuring light not transmitted through the 1/2 wavelength plate and received by the light receiving optical system.

8. The measurement arrangement according to claim 5,

the polarizing plate has an optical characteristic of transmitting only the same linearly polarized light as the distance measuring light.

9. The measurement arrangement according to claim 5,

the polarizing plate has an optical characteristic of transmitting only linearly polarized light orthogonal to the distance measuring light.

10. The measurement arrangement of claim 7,

the polarizing plate has an optical characteristic of transmitting only the same linearly polarized light as the distance measuring light.

11. The measurement arrangement of claim 7,

the polarizing plate has an optical characteristic of transmitting only linearly polarized light orthogonal to the distance measuring light.

Technical Field

The present invention relates to a measuring apparatus capable of acquiring point group data of an object to be measured.

Background

As the measuring device, there are a total station and a three-dimensional laser scanner. The total station is used for measuring a measurement target point. The three-dimensional laser scanner acquires the shape of the measurement object as three-dimensional point group data, which is a collection of numerous points having three-dimensional coordinates.

In recent years, software is used which automatically detects data of piping and structural steel included in point cloud data from a shape based on the point cloud data acquired by a three-dimensional laser scanner. By means of the software, CAD data of parts with the size mainly set according to industrial specifications is replaced by point group data, the data amount is reduced, comparison with design CAD data is facilitated, and the efficiency of operation is improved.

For example, in order to extract a pipe from the shape of the acquired point group data and match the pipe suitable for the size of the pipe with the point group, it is necessary to determine whether or not the shape of the point group is cylindrical with respect to all the point group data. Therefore, the process takes time, and the work efficiency is deteriorated.

Disclosure of Invention

An object of the present invention is to provide a measuring device capable of shortening the time required to extract a corresponding object from acquired point cloud data.

In order to achieve the above object, a measuring apparatus according to the present invention includes a light projecting optical system that projects a linearly polarized distance measuring light toward a measurement object, a light receiving optical system that receives a reflected distance measuring light from the measurement object, a polarization selecting unit that selects a polarized light of the reflected distance measuring light received by the light receiving optical system, a scanning mirror that is provided in the carriage unit and vertically rotates about a vertical rotation axis by a vertical rotation motor, irradiates the distance measuring light from the light projecting optical system toward the measurement object, and makes the reflected light from the measurement object incident on the distance measuring and light receiving optical system, the horizontal angle detecting unit detects a horizontal angle of the holder unit, the vertical angle detecting unit detects a vertical angle of the scanning mirror, and the calculation control unit controls distance measurement, rotation of the holder unit, and rotation of the scanning mirror based on a light receiving result of the reflected distance measuring light.

In the measuring apparatus according to the preferred embodiment, the polarization selection unit is a polarization beam splitter for separating the reflected distance measuring beam into P-polarized beam and S-polarized beam, the light receiving optical system includes a 1 st light receiving unit provided on a transmission optical axis of the polarization beam splitter, and a 2 nd light receiving unit provided on a reflection optical axis of the polarization beam splitter, and the calculation control unit compares the amount of light received detected by the 1 st light receiving unit with the amount of light received detected by the 2 nd light receiving unit.

In addition, the measuring apparatus according to a preferred embodiment further includes an 1/4 wavelength plate provided on a common optical path of the distance measuring light and the reflected distance measuring light.

In addition, the measuring apparatus according to a preferred embodiment further includes 1/4 wavelength plates provided on the optical axes of the distance measuring light and the reflected distance measuring light, respectively.

In the measuring apparatus according to the preferred embodiment, the polarized light selecting unit includes a polarizing plate that is provided on the optical axis of the reflected distance measuring light so as to be insertable and removable, and a polarizing plate driving unit that inserts and removes the polarizing plate, and the calculation control unit compares the received light amount of the reflected distance measuring light that has passed through the polarizing plate and has been received by the light receiving optical system with the received light amount of the reflected distance measuring light that has not passed through the polarizing plate and has been received by the light receiving optical system.

In the measuring apparatus according to the preferred embodiment, the polarization selection unit is a polarization beam splitter for separating the distance measuring light into P-polarized light and S-polarized light, the light projection optical system includes a 1 st light source unit disposed on a transmission optical axis of the polarization beam splitter for emitting the distance measuring light of the linearly polarized light, a 2 nd light source unit disposed on a reflection optical axis of the polarization beam splitter for emitting the distance measuring light of the linearly polarized light orthogonal to the linearly polarized light, and a polarization plate disposed on an optical axis of the reflected distance measuring light, and the calculation control unit compares the received light amounts of the distance measuring lights emitted from the 1 st light source unit and the 2 nd light source unit and detected by the light receiving optical system.

In the measuring apparatus according to the preferred embodiment, the polarized light selecting unit includes an 1/2 wavelength plate provided on the optical axis of the distance measuring light so as to be insertable and detachable, a wavelength plate driving unit for inserting and detaching the 1/2 wavelength plate, and a polarizing plate provided on the optical axis of the reflected distance measuring light, and the calculation control unit compares the received light amount of the reflected distance measuring light transmitted through the 1/2 wavelength plate and received by the light receiving optical system with the received light amount of the reflected distance measuring light received by the light receiving optical system without transmitting through the 1/2 wavelength plate.

In the measuring apparatus according to a preferred embodiment, the polarizing plate has an optical characteristic of transmitting only light of the same linearly polarized light as the distance measuring light.

Further, in the measuring apparatus according to a preferred embodiment, the polarizing plate has an optical characteristic of transmitting only light of linearly polarized light orthogonal to the distance measuring light.

According to the present invention, there is provided a projection optical system for projecting a linearly polarized distance measuring light to an object to be measured, a light receiving optical system for receiving a reflected distance measuring light from the object to be measured, a vertical angle detecting unit for receiving a reflected distance measuring light from the object to be measured, a polarization selecting unit for selecting the polarized light of the reflected distance measuring light received by the light receiving optical system, a carriage unit horizontally rotated about a horizontal rotation axis by a horizontal rotation motor, a scanning mirror provided in the carriage unit, vertically rotated about a vertical rotation axis by a vertical rotation motor, for projecting the distance measuring light from the projection optical system to the object to be measured and for causing the reflected distance measuring light from the object to be measured to enter the light receiving optical system, the horizontal angle detecting unit detects a horizontal angle of the bracket unit, the vertical angle detecting unit detects a vertical angle of the scanning mirror, the calculation control unit controls distance measurement, rotation of the bracket unit, and rotation of the scanning mirror based on a light receiving result of the reflected distance measuring light, and the calculation control unit is configured to give material information to a distance measuring result of the object to be measured based on a change in a light receiving amount caused by selection of polarized light by the polarized light selecting unit, and when extracting a metal component such as a pipe from point group data, it is sufficient to judge whether or not a shape of the point group is a cylindrical shape only for the point group judged to be metal, so that processing time can be shortened, and work efficiency can be improved.

Drawings

Fig. 1 is a front sectional view showing a measuring apparatus according to embodiment 1 of the present invention.

Fig. 2(a) is a schematic configuration diagram showing an optical system of the distance measuring unit according to embodiment 1, and fig. 2(B) is an explanatory diagram explaining a relationship between light amounts of the light source unit and the light receiving unit.

Fig. 3(a) is a schematic configuration diagram showing an optical system of the distance measuring unit according to embodiment 2, and fig. 3(B) is an explanatory diagram explaining a relationship between light amounts of the light source unit and the light receiving unit.

Fig. 4(a) is a schematic configuration diagram showing an optical system of the distance measuring unit according to embodiment 3, and fig. 4(B) is an explanatory diagram explaining a relationship between light amounts of the light source unit and the light receiving unit.

Fig. 5(a) is a schematic configuration diagram showing an optical system of the distance measuring unit according to embodiment 4, and fig. 5(B) is an explanatory diagram explaining a relationship between light amounts of the light source unit and the light receiving unit.

Fig. 6(a) is a schematic configuration diagram showing an optical system of the distance measuring unit according to embodiment 5, and fig. 6(B) is an explanatory diagram explaining a relationship between light amounts of the light source unit and the light receiving unit.

Fig. 7(a) is a schematic configuration diagram showing an optical system of the distance measuring unit according to embodiment 6, and fig. 7(B) is an explanatory view explaining a relationship between light amounts of the light source unit and the light receiving unit.

Fig. 8(a) is a schematic configuration diagram showing an optical system of the distance measuring unit according to embodiment 7, and fig. 8(B) is an explanatory diagram explaining a relationship between light amounts of the light source unit and the light receiving unit.

Detailed Description

Hereinafter, embodiments of the present invention will be described with reference to the drawings.

First, a measuring apparatus according to embodiment 1 of the present invention will be described with reference to fig. 1.

The laser scanner 1 includes an alignment unit 2 attached to a tripod not shown in the figure, and a scanner main body 3 provided in the alignment unit 2.

The calibration unit 2 has a calibration screw 4, and the scanner body 3 is calibrated by the calibration screw 4.

The measuring apparatus main body 3 includes a fixing portion 5, a bracket portion 6, a horizontal rotation shaft 7, a horizontal rotation bearing 8, a horizontal rotation motor 9 as a horizontal rotation driving portion, a horizontal angle encoder 11 as a horizontal angle detecting portion, a vertical rotation shaft 12, a vertical rotation bearing 13, a vertical rotation motor 14 as a vertical rotation driving portion, a vertical angle encoder 15 as a vertical angle detecting portion, a scanning mirror 16 as a vertical rotation portion, an operation panel 17 serving as both an operation portion and a display portion, a calculation control portion 18, a storage portion 19, a distance measuring portion 21 configured as an optical wave distance meter (EDM), and the like.

The horizontal rotary bearing 8 is fixed to the fixing portion 5. The horizontal rotation shaft 7 has a vertical shaft center 7a, and the horizontal rotation shaft 7 is rotatably supported by the horizontal rotation bearing 8. The bracket unit 6 is supported by the horizontal rotation shaft 7, and the bracket unit 6 rotates in the horizontal direction integrally with the horizontal rotation shaft 7.

The horizontal rotation motor 9 is provided between the horizontal rotation bearing 8 and the bracket unit 6, and the horizontal rotation motor 9 is controlled by the calculation control unit 18. The calculation control unit 18 rotates the bracket unit 6 about the axial center 7a by the horizontal rotation motor 9.

The relative rotation angle of the bracket portion 6 with respect to the fixing portion 5 is detected by the horizontal angle encoder 11. The detection signal from the horizontal angle encoder 11 is input to the calculation control unit 18, and the calculation control unit 18 calculates horizontal angle data. The calculation control unit 18 performs feedback control with respect to the horizontal rotation motor 9 based on the horizontal angle data.

The vertical rotation shaft 12 having a horizontal axis 12a is provided in the bracket portion 6. The vertical rotation shaft 12 is rotatable via the vertical rotation bearing 13. The intersection of the axis 7a and the axis 12a is the position from which the distance measuring light is emitted, and is the origin of the coordinate system of the scanner body 3.

A recess 20 is formed in the bracket portion 6. One end portion of the vertical rotation shaft 12 protrudes into the concave portion 20. The scanning mirror 16 is fixed to the one end portion, and the scanning mirror 16 is accommodated in the recess 20. The vertical angle encoder 15 is provided at the other end portion of the vertical rotation shaft 12.

The vertical rotation motor 14 is provided on the vertical rotation shaft 12, and the vertical rotation motor 14 is controlled by the calculation control unit 18. The calculation control unit 18 rotates the vertical rotation shaft 12 by the vertical rotation motor 14, and the scanning mirror 16 rotates about the shaft center 12 a.

The rotation angle of the scanning mirror 16 is detected by the vertical angle encoder 15, and a detection signal is input to the calculation control unit 18. The calculation control unit 18 calculates vertical angle data of the scanning mirror 16 based on the detection signal, and performs feedback control with respect to the vertical rotation motor 14 based on the vertical angle data.

Further, a general-purpose CPU or a CPU dedicated to the present apparatus is used as the calculation control unit 18. The horizontal angle data, the vertical angle data, the distance measurement result, the light receiving amount information (described later), and the material information (described later) calculated by the calculation control unit 18 are stored in the storage unit 19. The storage unit 19, which stores horizontal angle data, vertical angle data, distance measurement results, light receiving amount information, and material information, may be partially detachable from the bracket unit 6, or may be configured to transmit data to an external storage device or an external data processing device via a communication means not shown in the figure.

In addition, a hard disk drive, a memory card, a semiconductor memory, or the like is used as the storage unit 19. The storage unit 19 stores programs such as a program for measuring a distance and an angle of a measurement point, a program for driving the horizontal rotation motor 9 and the vertical rotation motor 14, a program for detecting the amounts of light received by P-polarized light and S-polarized light, respectively, which will be described later, and a program for determining whether a measurement object is made of metal or nonmetal based on the amounts of light received, which will be described later. The calculation control unit 18 executes various processes according to the embodiment of the present invention based on the programs stored in the storage unit 19.

The operation panel 17 is, for example, a touch panel, and also serves as an operation unit for performing an instruction to measure a distance, a measurement condition, for example, a change in a measurement point interval, and a display unit for displaying a distance measurement result, material information, and the like.

Next, in fig. 2(a), the distance measuring unit 21 will be described.

The distance measuring unit 21 includes a light projecting optical system 25 and a light receiving optical system 29. The light projection optical system 25 includes a light source unit 24 provided on a light projection optical axis 23, a light projection lens 32, a mirror 33, and a beam splitter 34 provided on a reflection optical axis of the mirror 33. The light receiving optical system 29 includes a 1 st light receiving unit 27 provided on the light receiving optical axis 26, a light receiving polarization beam splitter 28 serving as a polarization selection unit, a light receiving lens 35, and a 2 nd light receiving unit 31 provided on the reflection optical axis of the light receiving polarization beam splitter 28.

The beam splitter 34 is provided at a position where the light projection optical axis 23 and the light reception optical axis 26 intersect with each other. The light receiving optical axis 26 coincides with the transmission optical axis of the light receiving polarization beam splitter 28.

The light source unit 24 is a light emitting element such as a Laser Diode (LD), and emits a predetermined linearly polarized light, for example, a laser beam of P-polarized light as a distance measuring light in a pulse or burst (intermittent) manner on the light projecting optical axis 23.

The mirror 33 deflects the distance measuring light at a right angle. The beam splitter 34 has an optical characteristic of reflecting a part of the distance measuring light and transmitting a part of the reflected distance measuring light reflected by the object to be measured. Further, the beam splitter 34 deflects the distance measuring light toward the light receiving optical axis 26.

The light receiving polarization beam splitter 28 has optical characteristics of transmitting the P-polarized light beam that reflects the distance measuring light and reflecting the S-polarized light beam.

The 1 st light receiving unit 27 is a light receiving element such as an Avalanche Photodiode (APD), for example, and detects the amount of reflected distance measuring light of the P-polarized light transmitted by the light receiving polarization beam splitter 28. The 2 nd light receiving unit 31 is a light receiving element such as an APD, for example, and detects the amount of reflected distance measurement light of the S-polarized light reflected by the light receiving polarization beam splitter 28. The amounts of light detected by the 1 st light receiving unit 27 and the 2 nd light receiving unit 31 are stored in the storage unit 19, respectively. The optical path length between the 1 st light receiving unit 27 and the light receiving polarization beam splitter 28 and the optical path length between the 2 nd light receiving unit 31 and the light receiving polarization beam splitter 28 are the same.

The case of performing distance measurement by the measuring apparatus 1 will be described.

The light source unit 24 emits pulsed light of P-polarized light or distance measurement light of a burst light. The distance measuring light passes through the light projecting lens 32 and is then reflected by the mirror 33 and the beam splitter 34 in this order. The distance measuring light reflected by the beam splitter 34 enters the scanning mirror 16.

The optical axis of the distance measuring light entering the scanning mirror 16 coincides with the axial center 12a, and the distance measuring light is deflected at a right angle by the scanning mirror 16. The scanning mirror 16 rotates about the axis 12a, whereby the distance measuring light is orthogonal to the axis 12a and is rotated (scanned) in a plane including the axis 7 a. The distance measuring light reflected by the scanning mirror 16 is irradiated to a predetermined measuring point (irradiation point) of the object to be measured, and the object to be measured is scanned.

The reflected distance measuring light reflected by the measurement point enters the scanning mirror 16 and is reflected at a right angle by the scanning mirror 16. The reflected distance measuring light reflected by the scanning mirror 16 is transmitted through the beam splitter 34 and the light receiving lens 35 and enters the light receiving polarization beam splitter 28. The light of P-polarized light in the reflected distance measuring light incident on the light receiving polarization beam splitter 28 is transmitted through the light receiving polarization beam splitter 28 and received by the 1 st light receiving unit 27. The S-polarized light of the reflected distance measuring light incident on the light receiving polarization beam splitter 28 is reflected by the light receiving polarization beam splitter 28 and received by the 2 nd light receiving unit 31.

Fig. 2(B) is a graph showing a relationship among the amount of emitted distance measuring light 36 emitted from the light source unit 24, the amounts of received distance measuring light 37a and 38a of reflected distance measuring light of P-polarized light received by the 1 st light receiving unit 27, and the amounts of received distance measuring light 37B and 38B of reverse distance measuring light of S-polarized light received by the 2 nd light receiving unit 31.

In fig. 2(B), the horizontal axis represents time, and the size of the waveform represents the light intensity. In fig. 2(B), reference numerals 37a and 37B denote the light receiving amounts of the 1 st light receiving unit 27 and the 2 nd light receiving unit 31 in the case where the object to be measured is made of metal. In fig. 2(B), reference numerals 38a and 38B denote the light receiving amounts of the 1 st light receiving unit 27 and the 2 nd light receiving unit 31 in the case where the object to be measured is made of a non-metal. In fig. 2(B), for convenience, the total sum of the amounts of light received by the 1 st light receiving unit 27 and the 2 nd light receiving unit 31 is equal when the object to be measured is made of metal or nonmetal.

Here, it is understood that in the case of a metal measurement object, that is, in the case of a conductive measurement object, the distance measuring light is reflected while maintaining the polarization characteristics. Therefore, when the distance measuring light of P-polarization is emitted with respect to the metal object to be measured, as shown in fig. 2(B), the light receiving amount 37a of the 1 st light receiving unit 27 is detected to be larger than the light receiving amount 37B of the 2 nd light receiving unit 31.

On the other hand, in the case of a non-metallic object to be measured, that is, in the case of an object to be measured that is not conductive, it is known that the reflected distance measuring light is reflected without preserving polarization characteristics. Therefore, when the distance measuring light of P-polarized light is emitted to the non-metallic object to be measured, the reflected distance measuring light from the object to be measured is mixed with the light of P-polarized light and the light of S-polarized light. Therefore, as shown in fig. 2(B), the light receiving amount 38a of the 1 st light receiving unit 27 and the light receiving amount 38B of the 2 nd light receiving unit 31 are detected to be substantially the same.

Therefore, by comparing the amounts of the P-polarized light and the S-polarized light of the distance measuring light and the amounts of the P-polarized light and the S-polarized light of the reflected distance measuring light, the calculation control unit 18 can determine whether the measurement target is made of metal or nonmetal. Alternatively, the calculation control unit 18 can determine whether the object to be measured is made of metal or nonmetal by comparing the light reception result of the 1 st light receiving unit 27 with the light reception result of the 2 nd light receiving unit 31.

The calculation control unit 18 performs distance measurement (time of flight) for each pulse of the distance measurement light based on the timing of light emission by the light source unit 24, the time difference between the timing of light reception by the 1 st light receiving unit 27 and the timing of light reception by the 2 nd light receiving unit 31 for reflecting the distance measurement light (i.e., the round trip time of the pulsed light), and the light speed. The calculation control unit 18 can change the light emission timing of the light source unit 24, that is, the pulse interval.

Further, the calculation control unit 18 determines whether the object to be measured at the measurement point is made of metal or nonmetal based on the light reception results of the 1 st light receiving unit 27 and the 2 nd light receiving unit 31. In addition, as a light receiving signal for performing the distance measurement, the sum of the light receiving signal from the 1 st light receiving unit 27 and the light receiving signal from the 2 nd light receiving unit 31 is used. By using the sum of the light reception signals of the 1 st light receiving unit 27 and the 2 nd light receiving unit 31, the amount of received light is prevented from decreasing when P-polarized light and S-polarized light are divided. The distance measurement data obtained by the distance measurement and the determination data (material information) regarding whether the object to be measured is metallic or non-metallic are stored in the storage unit 19 in association with each measurement point.

Further, the holder portion 6 and the scanning mirror 16 are rotated at a constant speed, and the distance measuring light is two-dimensionally scanned by cooperation of the rotation of the scanning mirror 16 in the vertical direction and the rotation of the holder portion 6 in the horizontal direction. Further, by obtaining distance measurement data (oblique distance) for each pulse light distance measurement and detecting the vertical angle and the horizontal angle for each pulse light by the vertical angle encoder 15 and the horizontal angle encoder 11, it is possible to obtain vertical angle data and horizontal angle data. Three-dimensional point group data (position information) of the measurement object, which is provided with material information for each point, can be acquired from the vertical angle data, the horizontal angle data, the distance data, and the determination data.

As described above, in embodiment 1, since the light receiving polarization beam splitter 28 is provided on the light receiving optical axis 26 and the light amount of the P-polarized light and the light amount of the S-polarized light of the reflected distance measuring light can be detected, it is possible to determine whether the object to be measured is made of metal or non-metal based on the ratio of the P-polarized light and the S-polarized light of the distance measuring light and the ratio of the P-polarized light and the S-polarized light of the reflected distance measuring light.

Therefore, for example, when extracting a pipe from the point cloud data, it is sufficient to determine whether or not the shape of the point cloud is cylindrical only for the point cloud determined to be made of metal, and therefore, the processing time can be shortened and the work efficiency can be improved.

Further, since the light receiving polarization beam splitter 28 and the 2 nd light receiving unit 31 are only required to be provided for the conventional distance measuring unit 21, it is not necessary to add a large-sized device. Therefore, the function of determining the material of the object to be measured can be added without increasing the size of the measuring apparatus 1.

Next, embodiment 2 of the present invention will be described with reference to fig. 3(a) and 3 (B). In fig. 3(a) and 3(B), the same components as those in fig. 2(a) and 2(B) are denoted by the same reference numerals, and the description thereof is omitted.

In the distance measuring unit 21 according to embodiment 2, an 1/4 wavelength plate 39 that gives a phase difference of λ/4 is provided on the measurement object side, that is, on the common optical path between the distance measuring light and the reflected distance measuring light, compared to the beam splitter 34 of the light receiving optical axis 26. The 1/4 wavelength plate 39 has optical characteristics that give a retardation of λ/4 to the plane of polarization. The other structure is the same as that of embodiment 1.

The P-polarized pulse light or the burst light distance measuring light emitted from the light source unit 24 passes through the light projecting lens 32 and is then reflected by the mirror 33 and the beam splitter 34 in this order. The distance measuring light reflected by the beam splitter 34 passes through the 1/4 wavelength plate 39. When the distance measuring light passes through the 1/4 wavelength plate 39, a phase difference of λ/4 is given to the plane of polarization, and the distance measuring light becomes circularly polarized light.

The distance measuring light is irradiated to the measurement target via the scanning mirror 16 (see fig. 1). The reflected distance measuring light reflected by the object to be measured enters the 1/4 wavelength plate 39 again via the scanning mirror 16. When the object to be measured is made of metal, the polarized light is stored. Therefore, while passing through the 1/4 wavelength plate 39, the reflected range-finding light of circularly polarized light is the reflected range-finding light of S polarized light, and the reflected range-finding light sequentially passes through the beam splitter 34 and the light receiving lens 35 and enters the light receiving polarization beam splitter 28.

The light of P-polarized light in the reflected distance measuring light incident on the light receiving polarization beam splitter 28 is transmitted through the light receiving polarization beam splitter 28 and received by the 1 st light receiving unit 27. The S-polarized light of the reflected distance measuring light incident on the light receiving polarization beam splitter 28 is reflected by the light receiving polarization beam splitter 28 and received by the 2 nd light receiving unit 31.

In embodiment 2, the polarized light of the ranging light and the reflected ranging light is changed by the 1/4 wavelength plate 39 described above. Therefore, as shown in fig. 3(B), in the case of a metal measurement object, the light receiving amount 37B of the 2 nd light receiving unit 31 is detected to be larger than the light receiving amount 37a of the 1 st light receiving unit 27. On the other hand, in the case of a non-metal object to be measured, the light receiving amount 38a of the 1 st light receiving unit 27 and the light receiving amount 38b of the 2 nd light receiving unit 31 are detected to be substantially equal in magnitude.

Therefore, the calculation control unit 18 can determine the material of the measurement target, that is, whether the measurement target is made of metal or nonmetal, based on the comparison of the light quantity and the ratio of the light quantity of the P-polarized light to the S-polarized light of the distance measuring light, and the light quantity and the ratio of the light quantity of the P-polarized light to the S-polarized light of the reflected distance measuring light.

Further, the calculation control unit 18 can acquire three-dimensional point group data (position information) of the measurement target object, which gives material information to each point, based on the distance measurement result and the angle measurement result.

Next, embodiment 3 of the present invention will be described with reference to fig. 4(a) and 4 (B). In fig. 4(a) and 4(B), the same components as those in fig. 2(a) and 2(B) are denoted by the same reference numerals, and the description thereof is omitted.

In the distance measuring unit 21 of embodiment 3, a light projecting 1/4 wavelength plate 41 is provided between a light projecting lens 32 and a mirror 33 on a light projecting optical axis 23, and a light receiving 1/4 wavelength plate 42 is provided between a light receiving lens 35 and a beam splitter 34 on a light receiving optical axis 26. The light projecting 1/4 wavelength plate 41 and the light receiving 1/4 wavelength plate 42 each have optical characteristics that give a retardation of λ/4 to the plane of polarization. The other structure is the same as that of embodiment 1.

The P-polarized pulse light or the burst light distance measuring light emitted from the light source unit 24 is transmitted through the light projecting lens 32 and then enters the light projecting 1/4 wavelength plate 41. The distance measuring light is a distance measuring light which is converted into circularly polarized light by giving a phase difference of λ/4 to the plane of polarization in the process of passing through the light projecting 1/4 wavelength plate 41.

Then, the distance measuring light is reflected by the mirror 33 and the beam splitter 34 in this order, and is irradiated to the measurement object via the scanning mirror 16 (see fig. 1). The reflected range-finding light of the circularly polarized light reflected by the object to be measured is transmitted through the beam splitter 34 via the scanning mirror 16 and enters the light reception 1/4 wavelength plate 42. When the object to be measured is made of metal, the polarized light is stored. Therefore, while passing through the light-receiving 1/4 wavelength plate 42, the reflected range-finding light of circularly polarized light becomes the reflected range-finding light of S polarized light, and enters the light-receiving polarization beam splitter 28 through the light-receiving lens 35.

The light of P-polarized light in the reflected distance measuring light incident on the light receiving polarization beam splitter 28 is transmitted through the light receiving polarization beam splitter 28 and received by the 1 st light receiving unit 27. The S-polarized light of the reflected distance measuring light incident on the light receiving polarization beam splitter 28 is reflected by the light receiving polarization beam splitter 28 and received by the 2 nd light receiving unit 31.

In embodiment 3 as well, as shown in fig. 4(B), in the case of a metal measurement object, the light receiving amount 37B of the 2 nd light receiving unit 31 is detected to be larger than the light receiving amount 37a of the 1 st light receiving unit 27. On the other hand, in the case of a non-metal object to be measured, the light receiving amount 38a of the 1 st light receiving unit 27 and the light receiving amount 38b of the 2 nd light receiving unit 31 are detected to be substantially equal in magnitude.

Therefore, the calculation control unit 18 can determine the material of the measurement target, that is, whether the measurement target is made of metal or nonmetal, based on the comparison between the light quantity and the light quantity ratio of the P-polarized light and the S-polarized light of the distance measuring light and the light quantity ratio of the P-polarized light and the S-polarized light of the reflected distance measuring light. The calculation control unit 18 can acquire three-dimensional point group data (position information) of the measurement target object, which is obtained by giving material information to each point, based on the distance measurement result and the angle measurement result.

Next, an embodiment 4 of the present invention will be described with reference to fig. 5(a) and 5 (B). In fig. 5(a) and 5(B), the same components as those in fig. 2(a) and 2(B) are denoted by the same reference numerals, and the description thereof is omitted.

In the distance measuring unit 21 of embodiment 4, the light receiving polarization beam splitter 28, the 1 st light receiving unit 27, and the 2 nd light receiving unit 31 of embodiment 1 are omitted. On the other hand, embodiment 4 includes a light receiving unit 43 provided on the light receiving optical axis 26, a polarizing plate 44 having optical characteristics that can be inserted into and removed from the light receiving optical axis 26 and transmits only P-polarized light, and a polarizing plate driving unit 45 that inserts and removes the polarizing plate 44. The polarization selection unit is constituted by the polarizer 44 and the polarizer drive unit 45. The other structures are the same as those of embodiment 1.

In fig. 5(B), 46a shows the amount of light received by the light receiving unit 43 when the object to be measured is made of metal and the polarizing plate 44 is not present on the light receiving optical axis 26. Further, 46b represents the amount of light received by the light receiving unit 43 when the object to be measured is made of a non-metal and the polarizing plate 44 is not present on the light receiving optical axis 26. Further, 46c represents the amount of light received by the light receiving unit 43 when the object to be measured is made of metal and the polarizing plate 44 is disposed on the light receiving optical axis 26. Further, 46d represents the amount of light received by the light receiving unit 43 when the object to be measured is made of a non-metal and the polarizer 44 is disposed on the light receiving optical axis 26.

When the polarizing plate 44 is not present on the light receiving optical axis 26, the light receiving amounts 46a and 46b are detected, which are substantially the same as the light amount when the emitted light amount 36 is attenuated by the distance from the measurement object and the reflectance of the measurement object, regardless of whether the measurement object is made of metal or nonmetal. Therefore, in this case, it is not possible to determine whether the object to be measured is made of metal or nonmetal.

However, in the above case, the total amount of reflected distance measuring light is not reduced by the polarizing plate 44. Therefore, a sufficient amount of light for measuring the object to be measured can be secured, and the point cloud data of the object to be measured can be acquired with high accuracy.

When the polarizer 44 is disposed on the light receiving optical axis 26, the S-polarized light is removed from the reflected distance measuring light in the process in which the reflected distance measuring light passes through the polarizer 44. Therefore, even when the measurement object is made of metal, the reflected distance measuring light becomes P-polarized light substantially not including S-polarized light, and the light receiving amount 46c is detected which is substantially the same as the light amount when the emitted light amount 36 is attenuated by the distance from the measurement object and the reflectance of the measurement object. On the other hand, when the object to be measured is made of nonmetal, since the reflected distance measuring light is light including P-polarized light and S-polarized light in substantially equal amounts, the light receiving amount 46d is detected, which is a light amount substantially half the light amount when the emitted light amount 36 is attenuated by the distance from the object to be measured and the reflectance of the object to be measured.

In embodiment 4, the point group data of the object to be measured is acquired in a state where the polarizer 44 is not disposed on the light receiving optical axis 26, and the point group data of the object to be measured is acquired again in a state where the polarizer 44 is disposed on the light receiving optical axis 26. Then, the calculation control unit 18 compares the two light receiving amounts at the respective points, and determines whether the object to be measured is made of metal or nonmetal. The determination result (material information) is given to each point by the calculation control unit 18.

Next, an embodiment 5 of the present invention will be described with reference to fig. 6(a) and 6 (B). In fig. 6(a) and 6(B), the same components as those in fig. 5(a) and 5(B) are denoted by the same reference numerals, and the description thereof is omitted.

In the distance measuring unit 21 of the embodiment 5, the polarizer 44 of the embodiment 4 is a polarizer 47 that transmits only S-polarized light. Therefore, the polarization selector is constituted by the polarizer 47 and the polarizer driver 45. The other structures are the same as those of embodiment 4.

When the object to be measured is made of metal, if the polarizer 47 is disposed on the light receiving optical axis 26 as shown in fig. 6(B), the amount of light 46c detected by the light receiving unit 43 is substantially 0, except for P-polarized light from the reflected distance measuring light.

On the other hand, when the object to be measured is made of a non-metal, if the polarizing plate 47 is disposed on the light receiving optical axis 26, the light of P-polarized light is removed from the reflected distance measuring light, and the light receiving amount 46d detected by the light receiving unit 43 is approximately half of the light amount when the emitted light amount 36 is attenuated by the distance from the object to be measured and the reflectance of the object to be measured.

In embodiment 5, the point group data of the object to be measured is acquired in a state where the polarizer 47 is not disposed on the light receiving optical axis 26, and the point group data of the object to be measured is acquired again in a state where the polarizer 47 is disposed on the light receiving optical axis 26. Then, the calculation control unit 18 compares the two light receiving amounts at the respective points to determine whether the object to be measured is made of metal or nonmetal. The determination result (material information) is given to each point by the calculation control unit 18.

Alternatively, the polarizer 44 and the polarizer 47 may be inserted into and removed from the light receiving optical axis 26 in combination with embodiment 4 and embodiment 5.

Next, an embodiment 6 of the present invention will be described with reference to fig. 7(a) and 7 (B). In fig. 7(a) and 7(B), the same components as those in fig. 5(a) and 5(B) are denoted by the same reference numerals, and the description thereof is omitted.

In the distance measuring unit 21 according to embodiment 6, the light source unit of the light projecting optical system 25 is composed of the 1 st light source unit 48 and the 2 nd light source unit 49. The 1 st light source unit 48 is provided on the light projection optical axis 23. A light projecting polarization beam splitter 51 is provided on the light projecting optical axis 23, and the 2 nd light source unit 49 is provided on the reflection optical axis of the light projecting polarization beam splitter 51. The light projection optical axis 23 coincides with the transmission optical axis of the light projection polarization beam splitter 51.

The 1 st light source 48 emits the distance measuring light of P-polarized light. The 2 nd light source 49 emits distance measuring light of S-polarized light. The light projecting polarization beam splitter 51 has optical characteristics of transmitting the P-polarized light and reflecting the S-polarized light.

Further, a polarizing plate 52 is provided on the light receiving optical axis 26. The polarizer 52 has an optical characteristic of transmitting P-polarized light and shielding S-polarized light. The projection polarization beam splitter 51 and the polarizer 52 constitute a polarization selection unit.

In the embodiment 6, the distance measuring light alternately emits pulse light or burst light from the 1 st light source unit 48 and the 2 nd light source unit 49. The distance measuring light transmitted or reflected by the light projecting polarization beam splitter 51 is reflected by the object to be measured, and received by the light receiving unit 43 via the polarization plate 52.

Here, even when the object to be measured is made of metal, the polarization characteristics of the distance measuring light are stored in the reflected distance measuring light. Therefore, the distance measuring light of P-polarized light emitted from the 1 st light source unit 48 is received by the light receiving unit 43 as reflected distance measuring light of P-polarized light without reducing the light amount. Therefore, the light receiving unit 43 detects a light receiving amount 54a substantially equal to the light amount when the light amount 53 emitted from the 1 st light source unit 48 is reduced by the distance from the object to be measured and the reflectance of the object to be measured.

The distance measuring light of the S-polarized light emitted from the 2 nd light source unit 49 is shielded substantially entirely by the polarizer 52 as the reflected distance measuring light of the S-polarized light. Therefore, the light receiving amount 54b detected by the light receiving unit 43 is substantially 0.

On the other hand, when the object to be measured is made of nonmetal, the polarization characteristics of the distance measuring light are not preserved, and the distance measuring light is reflected so that the ratio of the P-polarized light to the S-polarized light is substantially the same. Therefore, the distance measuring light of P-polarized light emitted from the 1 st light source unit 48 is received by the light receiving unit 43 as a light receiving amount 54c, and the light receiving amount 54c is substantially half of the light amount when the emitted light amount 53 is attenuated by the distance from the object to be measured and the reflectance of the object to be measured.

The distance measuring light of the S-polarized light emitted from the 2 nd light source unit 49 is received by the light receiving unit 43 as a light receiving amount 54d, and the light receiving amount 54d is substantially half of the amount of light when the emitted light amount 55 is attenuated by the distance from the measurement object and the reflectance of the measurement object. That is, the light receiving amounts 54c and 54d detected by the light receiving unit 43 are substantially equal between the case where the distance measuring light is emitted from the 1 st light source unit 48 and the case where the distance measuring light is emitted from the 2 nd light source unit 49.

In embodiment 6, the calculation control unit 18 can determine whether the object to be measured is made of metal or nonmetal by comparing the amount of light received with respect to the amount of emitted light 53 with the amount of light received with respect to the amount of emitted light 55. The determination result (material information) is given to each point of the point cloud data by the calculation control unit 18.

Next, an embodiment 7 of the present invention will be described with reference to fig. 8(a) and 8 (B). In fig. 8(a) and 8(B), the same components as those in fig. 7(a) and 7(B) are denoted by the same reference numerals, and the description thereof is omitted.

In the distance measuring unit 21 according to embodiment 7, the light projecting polarization beam splitter 51 according to embodiment 6 is omitted, and the light source unit is constituted by one light source unit 24. The distance measuring unit 21 includes an 1/2 wavelength plate 56 provided on the light projection optical axis 23 so as to be insertable and detachable, and a wavelength plate driving unit 57 for inserting and detaching the 1/2 wavelength plate 56 with respect to the light projection optical axis 23. The 1/2 wavelength plate 56 has optical characteristics of light having a polarization direction orthogonal to the distance measuring light by giving a phase difference of λ/2 to the polarization plane of the distance measuring light emitted from the light source unit 24. The 1/2 wavelength plate 56, the wavelength plate drive unit 57, and the polarizer 52 constitute a polarization selection unit. The other structures are the same as those of embodiment 6.

When the P-polarized distance measuring light is emitted from the light source unit 24, the P-polarized distance measuring light is emitted when the 1/2 wavelength plate 56 is not present on the light projection optical axis 23, and the S-polarized distance measuring light is emitted when the 1/2 wavelength plate 56 is inserted on the light projection optical axis 23.

In fig. 8B, 46a shows the amount of light received when the object to be measured is made of metal and the 1/2 wavelength plate 56 is not present on the light projection optical axis 23 (when the distance measuring light is P-polarized light). Further, 46b represents the light receiving amount in the case where the object to be measured is made of a non-metal and the 1/2 wavelength plate 56 is not present on the light projecting optical axis 23 (the case where the distance measuring light is P-polarized light). Further, 46c represents the light receiving amount in the case where the object to be measured is made of metal and the 1/2 wavelength plate 56 is disposed on the light projection optical axis 23 (in the case where the distance measurement light is S-polarized light). Further, 46d represents the amount of light received when the object to be measured is made of a non-metal and the 1/2 wavelength plate 56 is disposed on the light projection optical axis 23 (when the distance measurement light is S-polarized light).

When the object to be measured is made of metal and the 1/2 wavelength plate 56 is not present on the light projecting optical axis 23, the reflected distance measuring light retains the P-polarized light, and the amount of light is not reduced by the polarizing plate 52, and the light receiving amount 46a substantially equal to the amount of light when the emitted light amount 36 is attenuated by the distance from the object to be measured and the reflectance of the object to be measured is detected. In the case where the object to be measured is made of a non-metal material and the 1/2 wavelength plate 56 is not present on the light projection optical axis 23, the light of the S-polarized light in the reflected distance measuring light mixed with the S-polarized light and the P-polarized light is shielded by the polarizer 52. Therefore, the light receiving amount 46b, which is substantially half of the emitted light amount 36, is detected.

In the case where the object to be measured is made of metal and the 1/2 wavelength plate 56 is disposed on the light projection optical axis 23, the 1/2 wavelength plate 56 emits the distance measuring light of S-polarized light, and the reflected distance measuring light storing the S-polarized light is substantially completely shielded by the polarizer 52. Therefore, the light receiving amount 46c detected by the light receiving unit 43 is substantially 0. When the object to be measured is made of a non-metal and the 1/2 wavelength plate 56 is disposed on the light projecting optical axis 23, the distance measuring light of S-polarized light is emitted. The light of the S-polarized light in the reflected distance measuring light in which the S-polarized light and the P-polarized light are mixed is shielded by the polarizer 52, and the received light amount 46d, which is substantially half the amount of the emitted light 36 when the distance from the measurement object and the reflectance of the measurement object decay, is detected.

In embodiment 7, when measuring an object to be measured, point group data of the object to be measured is acquired in a state where the 1/2 wavelength plate 56 is not present on the light projection optical axis 23. Next, the 1/2 wavelength plate 56 is disposed on the light projection optical axis 23, and point group data of the object to be measured is acquired.

The measurement points of the two acquired point group data are substantially the same coordinates. When measuring points located at the same coordinates are compared with each other, if the object to be measured is made of metal, different amounts of light received are detected. On the other hand, when the object to be measured is made of a non-metal material, substantially the same amount of light received is detected.

Therefore, in embodiment 7, by comparing the light receiving amount at each measurement point of the obtained two point group data, the calculation control unit 18 can determine whether the object to be measured is made of metal or nonmetal.

In the present invention, the 1/4 wavelength plate 39, the light projection 1/4 wavelength plate 41 and the light reception 1/4 wavelength plate 42 are provided in embodiments 2 and 3, but it is obvious that the 1/4 wavelength plate 39, the light projection 1/4 wavelength plate 41 and the light reception 1/4 wavelength plate 42 can be applied to embodiments 4 to 7.