JP2011232127A - Surveying instrument - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a surveying instrument which facilitates the adjustment of an optical axis with a simple configuration and is not affected by disturbance.SOLUTION: A surveying instrument 1 includes a surveying unit 10 and a survey object unit 20. The surveying unit 10 is provided with: an SLD11 which emits light having a first wavelength band and performs laser oscillation by return light from the outside; a collimator lens 13 for collimating light emitted from the SLD11; a diffraction grating 14 which has a diffraction angle varying according to a wavelength of light and disperses collimated light from the collimator lens 13 within a predetermined angle range corresponding to the first wavelength band in a first plane. The survey object unit 20 is provided with a CCP21 which is disposed within the predetermined angle range in the first plane and reflects light impinging thereon toward an incident direction to return the light to the SLD11. The surveying unit 10 is provided with a spectrum measuring unit 15 which takes in a part of laser-oscillated light to measure the spectrum, and a position detection unit 18 which calculates a position of the survey object unit 20 on the basis of the spectrum of the light measured by the spectrum measuring unit 15.

Description

  The present invention relates to a surveying apparatus that performs surveying using light.

  Conventionally, surveying apparatuses that measure distance and direction using laser light have been used in the fields of civil engineering and architecture. This surveying instrument performs surveying by emitting laser light from a measurement point to a measurement object and detecting and detecting return light from the measurement object. Therefore, in the surveying instrument, it is necessary to adjust the optical axis so that the reflected light from the measurement object returns to the measurement point.

  In this regard, Patent Document 1 discloses a surveying apparatus that emits a laser beam from a surveying target means arranged at a surveying target point to a surveying means arranged at the measurement point, by providing a two-dimensional scanning device on the surveying target means. A technique for automatically aiming the surveying means to the survey target means is disclosed.

Japanese Patent Laid-Open No. 63-281012

  However, in the surveying device of Patent Document 1, it is necessary to incorporate a two-dimensional scanning device, which is a mechanical and electrical drive mechanism, into the surveying target means, which increases the cost of the surveying device and increases the size of the device. There is a problem. Therefore, there has been a demand for a surveying device that does not require a mechanical and electrical search mechanism, that is, a surveying device that facilitates optical axis alignment with a simpler configuration.

  Further, in Patent Document 1, the return light of the light emitted from the surveying means toward the survey target means is detected and the position is measured, but the return light also includes a noise component due to disturbance. There is also the problem of being deceived.

  The present invention has been made in view of the above circumstances, and an example of the problem is to provide a surveying device that facilitates optical axis adjustment with a simple configuration and is not affected by disturbance. is there.

  In order to achieve the above object, one aspect of the present invention is a surveying apparatus including a surveying unit and a surveying target unit, and the surveying unit emits light in the first wavelength band and is externally transmitted. A light source that oscillates by return light, a collimator element that collimates the light emitted from the light source, a diffraction angle varies depending on the wavelength of the light, and the collimated light from the collimator element is converted into the first plane. And a dispersion optical element that disperses within a predetermined angle range corresponding to the first wavelength band, and the survey target part is disposed within the predetermined angle range in the first plane. A retroreflecting material that reflects the light that has reached through the dispersion optical element in the original direction and returns the light to the light source, and the surveying unit is an optical element that extracts a part of the light that is laser-oscillated by the light source; Spectra of light extracted by the optical element A spectrum measuring section for measuring the Le, on the basis of the spectrum of light measured by the spectrum measuring section, and further comprising a position detection unit for calculating the position of the surveying object part.

1 is a schematic configuration diagram of a surveying instrument according to a first embodiment of the present invention. It is a figure which shows the diffraction direction of the light which injects into a diffraction grating. It is a figure which shows the diffusion direction of the light radiate | emitted from the light source in the surveying instrument which concerns on the 1st Embodiment of this invention. It is a figure which shows the position of the survey object part arrange | positioned on a diffusion area | region in the survey apparatus which concerns on the 1st Embodiment of this invention. It is a figure which shows the light spot on the line sensor at the time of arrange | positioning a survey object part in each position shown in FIG. 4, and the spectrum of light. In the surveying instrument concerning a 1st embodiment of the present invention, it is a graph which shows the relation between the ratio which takes out light to a spectrum measurement part, and the optical output of a spectrum measurement part. It is a figure which shows the external appearance of the retroreflection material of the surveying instrument which concerns on the 2nd Embodiment of this invention. In the surveying apparatus according to the second embodiment of the present invention, how the light travels when the surveying target portion is displaced in the direction in which the light is not dispersed is compared with the surveying apparatus according to the first embodiment. It is a figure to do. It is a schematic block diagram of the surveying instrument which concerns on the 3rd Embodiment of this invention. It is a schematic block diagram of the surveying instrument which concerns on the 4th Embodiment of this invention.

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

<First Embodiment>
FIG. 1 is a schematic configuration diagram of a surveying apparatus 1 according to the first embodiment of the present invention. The surveying apparatus 1 shown in FIG. 1 includes a surveying unit 10 and a surveying target unit 20, the surveying target unit 20 reflects the laser light emitted from the surveying unit 10, and the surveying unit 10 receives the reflected light. Thus, the position of the survey target part 20 is detected.

  As the light source 11 of the surveying unit 10, for example, a super-luminescent diode (hereinafter referred to as SLD) having a wider spectral line width than a normal semiconductor laser (hereinafter referred to as LD) is suitable. is there. The SLD 11 emits light having a broad spectrum (determined by the laser medium. For example, the center wavelength is 950 nm and the line width is 60 nm) based on the control of the light source driving unit 12. The SLD 11 is manufactured by applying an antireflection coating that makes the reflectance as close to zero as possible on one end face of the laser medium of the LD. That is, the antireflection coating is applied to one end surface of the SLD 11 on the laser beam emission side, and the antireflection coating is not applied to the other end surface. For this reason, the SLD 11 alone does not oscillate. In the present embodiment, as will be described later, the SLD 11 is used as an external resonator type laser.

  The light emitted from the SLD 11 is converted into parallel light by a collimator lens 13 which is a collimator element, and the parallel light is diffracted by a diffraction grating 14 which is a dispersion optical element.

Here, the diffraction direction (strengthening direction) of the light passing through the diffraction grating 14 will be described with reference to FIG. FIG. 2 is a diagram showing the diffraction direction of light incident on the diffraction grating 14 having a grating pitch of N (the number of gratings per unit length. The grating interval is 1 / N). When the wavelength of incident light is λ, the incident angle is α, the diffraction angle is β, and the diffraction order is m,
sin α + sin β = Nmλ (1)
Therefore, the diffraction angle β differs for each wavelength.

  That is, when light having a wide spectrum is incident on the diffraction grating 14, the diffracted light is diffused and propagated as shown in FIG. FIG. 3 is a diagram illustrating the diffusion direction of the light emitted from the SLD 11. More specifically, from the above equation (1), the longer the wavelength, the larger the diffraction angle β. Therefore, when the wavelength λ of the incident light is λ1 ≦ λ ≦ λ2, the light of wavelength λ1 is the A direction and the light of wavelength λ2 is The S region traveling in the B direction and surrounded by the A direction and the B direction becomes the traveling direction of the diffracted light. In the present embodiment, as shown in FIGS. 1 and 3, the light emitted from the SLD 11 will be described as being dispersed in a direction (paper surface direction) parallel to the XY plane.

  In general, when light emitted from the SLD 11 is reflected by a reflecting member (reflector) disposed outside the SLD 11 and returned to the SLD 11, it becomes an external resonator type LD light source, and it is known that the SLD 11 oscillates. ing. As an application example using this characteristic and a diffraction grating, there is a wavelength-tunable external resonator laser. In the case of a tunable external resonator type laser, light is dispersed by a diffraction grating to select the wavelength, and only light of a specific wavelength is returned to the LD light source, thereby realizing laser oscillation with a narrow band spectrum selectively. ing. Based on the principle of this wavelength-tunable external cavity laser, the traveling region of diffused light dispersed by the diffraction grating 14 (hereinafter referred to as the diffusion region, specifically, the S region in FIG. 3) By arranging a reflecting member 21 such as a mirror and returning the light reflected by the reflecting member 21 to the SLD 11, laser oscillation can be caused. In other words, if the surveying target unit 20 including the reflecting member 21 is arranged in any of the diffusion regions (S region in FIG. 3), a laser resonator is automatically constructed by the surveying unit 10 and the surveying target unit 20. From the surveying unit 10, laser light having a specific wavelength corresponding to the position of the surveying target unit 20 is emitted. When laser oscillation occurs, the spectrum of the light emitted from the SLD 11 becomes a narrow band, so that the diffusion angle of the light dispersed by the diffraction grating 14 becomes narrow.

  As the reflecting member 21 of the survey target 20, a retroreflecting material such as a corner cube prism (hereinafter referred to as CCP) is suitable. The CCP 21 has a recursive property of reflecting incident light in the original direction (the same direction as the incident light). In the present embodiment, by utilizing the characteristics of the CCP 21, the light incident from the diffraction grating 14 is reflected in the same direction, and the reflected light is returned to the SLD 11 through the diffraction grating 14.

  Here, the spectrum of the light of the laser-oscillated SLD 11 will be described with reference to FIGS. FIG. 4 is a diagram showing the position of the survey target unit 20 arranged on the diffusion region, and FIG. 5 is a light spot on the line sensor 153 when the survey target unit 20 is arranged at each position shown in FIG. It is a figure which shows the spectrum of light. The line sensor 153 is one of the components of the spectrum measurement unit 15 described later, and the spectrum measurement unit 15 of the present embodiment measures the light spectrum from the position and size of the light spot on the line sensor 153. It is supposed to be.

  The spectrum of the light of the laser-oscillated SLD 11 differs depending on the position of the survey target 20 as shown in FIGS. This is because only light having a specific wavelength out of the light dispersed by the diffraction grating 14 is returned to the SLD 11 by the survey target 20 (CCP 21). FIG. 5A shows a light spot and a light spectrum on the line sensor 153 when the survey target unit 20 is arranged at points C, D, and E having the same distance from the survey unit 10 and different directions. ing. Assuming that the center wavelengths of the SLD 11 when the survey target 20 is placed at the points C, D, and E are λC, λD, and λE, respectively, the light of the SLD 11 that oscillates as it proceeds from the A direction to the B direction as described above. Since the wavelength becomes longer, the center wavelength of the spectrum of the light measured at the points C, D, and E is λD <λC <λE as shown in FIG. That is, the direction from the surveying unit 10 to the survey target unit 20 can be specified based on the peak position of the light spectrum (the position of the light spot on the line sensor 153). In addition, when the surveying target unit 20 moves, for example, when the surveying target unit 20 moves from the point C to the point D, the center wavelength of the spectrum changes from λC to λD. The movement angle with respect to the light dispersion direction (direction parallel to the XY plane) can be obtained.

  FIG. 5B shows a light spot and a light spectrum on the line sensor when the survey target unit 20 is arranged at points F, C, and G having the same direction from the survey unit 10 and different distances. Yes. If the spectral width of the SLD 11 when the survey target 20 is placed at points F, C, and G are ΔλF, ΔλC, and ΔλG, respectively, the wavelength width that returns to the SLD 11 becomes narrower as the distance from the survey unit 10 increases. As shown in FIG. 5B, ΔλF> ΔλC> ΔλG. That is, the distance from the surveying unit 10 to the survey target unit 20 can be specified based on the peak width of the light spectrum (the size of the light spot on the line sensor). Further, when the surveying target unit 20 moves, for example, when the surveying target unit 20 moves from the point C to the point G, the spectral width changes from ΔλC to ΔλG. Therefore, the travel distance of the surveying target unit 20 from the amount of change in the spectral width. Can be requested.

  From the above, in the present embodiment, the position of the survey target unit 20 can be calculated by measuring the spectrum of the light of the laser-oscillated SLD 11 and obtaining the center wavelength and spectrum width of the spectrum.

  Specifically, in the present embodiment, the spectrum measurement unit 15 has a function of measuring the spectrum of the light of the SLD 11 that is laser-oscillated, and the position detection unit 18 uses the measurement result of the spectrum measurement unit 15 to measure the measurement target unit 20. It has a function to calculate the position.

  Specifically, the spectrum measurement unit 15 includes a diffraction grating 151, a condensing lens 152, and a line sensor 153. However, the spectrum measurement unit 15 may have any other configuration as long as it is a device capable of measuring the spectrum of light. A spectroscope or an optical spectrum analyzer may be used. In the present embodiment, by adopting the configuration of the diffraction grating 151, the condensing lens 152, and the line sensor 153, the light incident on the spectrum measuring unit 15 is on the line sensor 153 according to the wavelength band of the light. Condensed at different positions. That is, as shown in FIG. 5, the light intensity distribution on the line sensor 153 varies depending on the position of the survey target 20.

  The position detection unit 18 performs a calculation for converting the spectrum information measured by the spectrum measurement unit 15 into the position coordinates of the survey target 20. Specifically, the distance between the surveying unit 10 and the survey target unit 20 is calculated from the center wavelength of the light spectrum, the direction of the survey target unit 20, and the peak width of the light spectrum, and the light dispersion plane (parallel to the XY plane). The position coordinates (two-dimensional position coordinates) of the surveying target unit 20 in the plane are calculated.

  Conventionally, in order to transmit a laser beam from a surveying unit to a surveying target unit and detect a return light from the surveying target unit, a search mechanism such as a two-dimensional scanning device is incorporated on the surveying unit side. It was necessary to align the optical axis. However, in the present embodiment, if the surveying target unit 20 (CCP21) is placed somewhere in the diffusion region (S region in FIG. 3) having a predetermined angle, the surveying unit 10 and the surveying target unit 20 automatically. Since the laser resonator is constructed and the spectrum of the return light can be measured by the spectrum measuring unit 15, it is not necessary to precisely align the optical axis. That is, the surveying apparatus 1 can easily adjust the optical axis with a simple configuration in which a dispersion optical element is provided on the surveying unit 10 side and a retroreflecting material is provided on the surveying target unit 20 side. It is possible to increase the tolerance of positional deviation with respect to the light dispersion direction (direction parallel to the XY plane).

  Between the collimator lens 13 and the diffraction grating 14 of the surveying unit 10, a half-wave plate 16 and a PBS (polarizing beam splitter) which are optical elements for taking a part of the laser-oscillated SLD 11 light into the spectrum measuring unit 15. ) 17 is arranged. Specifically, the light emitted from the SLD 11 is converted into parallel light by the collimator lens 13, and a part of the parallel light is taken into the spectrum measurement unit 15 via the half-wave plate 16 and the PBS 17, and the rest is , And is incident on the diffraction grating 14 through the half-wave plate 16 and the PBS 17. The amount of light taken into the spectrum measuring unit 15 can be adjusted by controlling the rotation of the half-wave plate 16.

  Here, in order for the spectrum measurement unit 15 to perform measurement with a high S / N ratio, it is necessary to capture as much light as possible into the spectrum measurement unit 15. The magnitude of the light output taken out by the spectrum measuring unit 15 is the ratio η (= the amount of light taken out by the spectrum measuring unit 15) of the light extracted from the light emitted by the laser resonator constructed by the surveying unit 10 and the survey target unit 20. / Total amount of light inside the laser resonator (hereinafter also referred to as light extraction efficiency). FIG. 6 is a graph showing the relationship between the light extraction efficiency η obtained by the experiment and the light output taken into the spectrum measuring unit 15. The light output taken into the spectrum measuring unit 15 is standardized, and the light output when the light extraction efficiency η = 0.8 is 1.

  As shown in FIG. 6, if the light extraction efficiency η is too small, the amount of light to be extracted is small, and the magnitude of the light output taken into the spectrum measuring unit 15 is also small. On the other hand, if the light extraction efficiency η is too large, the amount of light returning to the SLD 11 is reduced, so that the laser oscillation is weakened and the magnitude of the light output taken into the spectrum measuring unit 15 is also reduced. Therefore, by selecting an appropriate light extraction efficiency η, the spectrum measuring unit 15 can obtain the maximum light output (η = 0.8 in FIG. 6). In the present embodiment, the light extraction efficiency η is set in advance so that the spectrum measurement unit 15 can obtain the maximum light output. Specifically, the half-wave plate 16 is controlled so that the spectrum measuring unit 15 can obtain the maximum light output.

  Further, in the present embodiment, since the light emitted from the SLD 11 is taken into the spectrum measuring unit 15, even if disturbance (noise component) is included in the return light from the survey target unit 20, the spectrum measuring unit At 15, the spectrum of the disturbance light is not measured. This is because the disturbance light does not contribute to laser oscillation and is not included in the light emitted from the SLD 11. Also in this sense, the spectrum measurement unit 15 can perform measurement with a high S / N ratio.

  As described above, according to the surveying apparatus 1 of the present embodiment, the surveying unit 10 emits light in the first wavelength band and laser oscillates by return light from the outside, and light emitted from the SLD 11 The collimator lens 13 that makes the parallel light different in diffraction angle depending on the wavelength of the light, and the parallel light from the collimator lens 13 is within the range of a predetermined angle corresponding to the first wavelength band in the first plane. The surveying target unit 20 is disposed within a range of a predetermined angle in the first plane, reflects the light that has reached through the diffraction grating 14 in the original direction, The surveying unit 10 includes a CCP 21 that returns to the SLD 11, and the surveying unit 10 extracts a part of the laser-oscillated light of the SLD 11 and the half-wave plate 16 and the PBS 17, and the light extracted by the half-wave plate 16 and the PBS 17. Since it further includes a spectrum measuring unit 15 that measures the spectrum, and a position detecting unit 18 that calculates the position of the survey target unit 20 based on the spectrum of the light measured by the spectrum measuring unit 15, a simple configuration Thus, the optical axis can be easily adjusted, and the tolerance of the positional deviation in the direction of light dispersion of the survey target 20 can be increased, and it is not affected by disturbance.

  The position detection unit 18 detects the direction of the survey target unit 20 with respect to the surveying unit 10 based on the peak position of the light spectrum measured by the spectrum measurement unit 15, and the spectrum of the light spectrum measured by the spectrum measurement unit 15. Since the distance between the surveying unit 10 and the survey target unit 20 is calculated based on the spectrum width, the two-dimensional position coordinates of the survey target unit 20 can be obtained.

  The size of the diffusion region is determined from the above equation (1) using the incident angle α and wavelength λ of light incident on the CCP 21 and the value of the grating pitch N as parameters. In the present embodiment, The value of this parameter is determined according to the application of the surveying instrument 1, and a suitable size of the diffusion region is set.

  It is possible to use a dispersion optical element as a lens instead of the diffraction grating 14 and generate diffused light using the lens. However, when a lens is used, a part of the light for all wavelengths returns to the SLD 11. As a result, energy loss increases. On the other hand, when the dispersion optical element is the diffraction grating 14 as in the present embodiment, all light of a specific wavelength is returned to the SLD 11, so that there is an effect that energy loss is small. As a result, if the survey target unit 20 is arranged in the diffusion region, surveying is possible even if the distance between the survey unit 10 and the survey target unit 20 is a long distance.

<Second Embodiment>
In the first embodiment, the tolerance of displacement of the survey target 20 with respect to the light dispersion direction (direction parallel to the XY plane) is large, but the direction in which light is not dispersed (Z which is a direction perpendicular to the XY plane). With respect to (direction), the tolerance of the position shift of the survey target 20 is small. Therefore, in the second embodiment, as the retroreflecting material, using the CCP array 21A arrayed in the direction in which light is not dispersed (Z direction), the receiving unit 20 is also used in the direction in which light is not dispersed (Z direction). The tolerance of misalignment is increased.

  FIG. 7A is an external view of the CCP array 21A. As shown in FIG. 7A, the CCP array 21A is configured by arraying in the Z direction a plurality of CCPs 24 that are sufficiently small with respect to the size of the diffraction grating 14 in the Z direction.

  FIG. 8A is a diagram illustrating how light travels when the CCP 21 is displaced in the direction in which light is not dispersed (Z direction) in the first embodiment, and FIG. In the second embodiment, it is a diagram showing how light travels when the CCP array 21A is displaced in a direction in which light is not dispersed (Z direction). As shown in FIG. 8A, when the CCP 21 is used as the retroreflecting material, the optical axis is shifted in the direction in which the light is not dispersed (Z direction). Cannot pass through the diffraction grating 14. On the other hand, when the CCP array 21A is used, the optical axis deviation amount in the return path can be reduced by reducing the size of the CCP 24 even if the optical axis deviation occurs in the direction in which light is not dispersed (Z direction). Therefore, the loss of the return light amount can be reduced.

  Therefore, according to the surveying instrument 2 of the second embodiment, the retroreflecting material is arranged in an array in a direction perpendicular to the first plane (direction in which light is dispersed) (direction in which light is not dispersed). 21A, and the size of each CCP 24 constituting the CCP array 21A is sufficiently small with respect to the size in the direction perpendicular to the first plane of the diffraction grating 14 (the direction in which light is not dispersed). In addition to the effects of the embodiment, it is possible to increase the tolerance of the positional deviation of the receiving unit 20 in the direction in which light is not dispersed (Z direction).

<Third Embodiment>
FIG. 9 is a schematic configuration diagram of the surveying apparatus 3 according to the third embodiment. In the third embodiment, the survey target unit 30 includes a light receiving element 22 and an operation unit 23 in addition to the CCP 21.

  The light receiving element 22 is disposed on the reflection surface of the CCP 21. The light receiving element 22 is a photoelectric conversion element that converts light into an electrical signal. The light receiving element 22 extracts a part of the light incident on the reflection surface of the CCP 21 and performs photoelectric conversion. As the photoelectric conversion element, for example, a photodiode or a solar cell is assumed. In the case of a photodiode, a light modulation signal is converted into an electric modulation signal. In the case of a solar cell, light energy is converted into electric energy. Convert. The converted electrical modulation signal or electrical energy is sent to the operating unit 23.

  Therefore, according to the surveying apparatus 3 of the third embodiment, the CCP 21 reflects a part of the light that has reached through the diffraction grating 14 in the original direction and returns it to the SLD 11. 14 further includes a light receiving element 22 that converts the remainder of the light that has reached via 14 into an electrical signal, so that in addition to the effects of the first embodiment, information is sent from the surveying unit 10 to the surveying target unit 30. Can be sent. In addition, by using this optical communication, it is possible to supply power to the survey target 30.

  In the third embodiment, the light receiving element 22 is disposed on the reflection surface of the CCP 21. However, as shown in FIG. 7B, for example, the CCP 24 and the light receiving element (photoelectric conversion) are arranged. Elements) 25 may be mixed in the Z direction to form an array. In this case, the value of the light extraction efficiency η can be controlled by the ratio of the areas of the CCP 24 and the light receiving element 25. The sizes of the CCP 24 and the light receiving element 25 are sufficiently small with respect to the beam diameter of the laser light reflected on the CCP array 21B.

<Fourth embodiment>
FIG. 10 is a schematic configuration diagram of a surveying instrument 4 according to the fourth embodiment. In the fourth embodiment, the surveying unit 40 includes a one-dimensional scanner 101 that scans light in a direction in which light is not dispersed (Z direction), and a scanner control unit 19 that controls the angle of the one-dimensional scanner 101. Yes.

  As the one-dimensional scanner 101, for example, a galvano scanner is assumed. Since the scanner control unit 19 can control the angle of the one-dimensional scanner 101 in the direction in which light is not dispersed (Z direction), the light emitted from the SLD 11 is scanned in the direction in which light is not dispersed (Z direction). When the laser measurement of the SLD 11 is confirmed in the spectrum measurement unit 15, the scanner control unit 19 stops the scanning of the one-dimensional scanner 101, and the angle when the laser oscillation is confirmed (an angle in the direction in which light dispersion is not performed). Is output to the position detector 18. As a result, the position detection unit 18 can calculate the position of the survey target unit 20 in the direction of light dispersion (a plane parallel to the XY plane) from the spectrum information measured by the spectrum measurement unit 15, as well as scanner control. Since the position of the survey target 20 in the direction in which light is not dispersed (Z direction) can be calculated from the angle information output from the unit 19, the three-dimensional position coordinates of the survey target 20 can be obtained.

  Therefore, according to the optical wireless transmission device 4 of the fourth embodiment, the surveying unit 40 scans the light emitted from the SLD 11 in a direction perpendicular to the first plane (a direction in which light is not dispersed). And a scanner control unit 19 for controlling the scanning angle of the one-dimensional scanner 101. When the laser measurement of the SLD 11 is confirmed by the measurement of the spectrum measurement unit 15, the scanner control unit 19 The scanning of the scanner 101 is stopped and the angle when the laser oscillation is confirmed is output to the position detection unit 18, and the position detection unit 18 takes into account the scanning angle when the laser oscillation is confirmed, Since the position of the unit 20 is calculated, the three-dimensional position of the survey target unit 20, that is, the distance from the survey unit 40 to the survey target unit 20, the horizontal angle and the vertical angle can be measured. That.

  Note that a mechanism for scanning light in a direction in which light is not dispersed (Z direction) is not limited to the one-dimensional scanner 101, and may be another mechanism. For example, a mechanism that tilts the entire surveying unit 10 in a direction (Z direction) in which light is not dispersed may be used.

  Although the embodiments of the present invention have been described above, the present invention is not limited to the above-described embodiments, and various modifications can be made to the embodiments of the present invention without departing from the gist of the present invention. Such modifications and changes can be made, and those accompanying such modifications and changes are also included in the technical scope of the present invention.

1,2,3,4 Surveying device 10,40 Surveying unit 11 SLD (light source)
12 Light source drive unit 13 Collimator lens (collimator element)
14 Diffraction grating (dispersion optical element)
15 Spectrum Measurement Unit 16 1/2 Wave Plate 17 PBS
18 Position detection unit 19 Scanner control unit 20, 30 Survey target unit 21, 24 CCP (reflection member)
21A, 21B CCP array (reflective member)
22, 25 Photoelectric conversion element (light receiving element)
23 Operation Unit 101 One-dimensional Scanner 151 Diffraction Grating 152 Condensing Lens 153 Line Sensor

Claims (5)

A surveying device having a surveying unit and a surveying target unit,
The surveying unit
A light source that emits light in the first wavelength band and that oscillates with return light from the outside;
A collimating element that collimates the light emitted from the light source;
A dispersion optical element having a diffraction angle different according to a wavelength of light, and dispersing the parallel light from the collimating element within a predetermined angle range corresponding to the first wavelength band in a first plane;
With
The survey target part is
A retroreflecting material that is disposed within the range of the predetermined angle in the first plane, reflects the light that has reached through the dispersion optical element in the original direction, and returns the light to the light source;
The surveying unit
An optical element for extracting a part of the laser light emitted from the light source;
A spectrum measuring unit for measuring a spectrum of light taken out by the optical element;
A position detection unit that calculates the position of the survey target unit based on the spectrum of light measured by the spectrum measurement unit;
A surveying apparatus, further comprising: The retroreflecting material is arranged in an array in a direction perpendicular to the first plane,
2. The surveying according to claim 1, wherein the size of each of the arrayed retroreflecting materials is sufficiently smaller than the size of the dispersion optical element in a direction perpendicular to the first plane. apparatus. The retroreflecting material reflects a part of the light that has reached through the dispersion optical element in the original direction and returns it to the light source,
The survey target part is
The surveying apparatus according to claim 1, further comprising a light receiving element that converts a remaining part of the light that has reached through the dispersion optical element into an electric signal. The surveying unit
A one-dimensional scanning unit that scans light emitted from the light source in a direction perpendicular to the first plane;
A scanning control unit for controlling a scanning angle of the one-dimensional scanning unit;
Further comprising
When the laser measurement of the light source is confirmed by the measurement of the spectrum measurement unit, the scanning control unit stops the scanning of the one-dimensional scanning unit and sets the angle when the laser oscillation is confirmed. Output to the position detector,
The surveying apparatus according to claim 1, wherein the position detection unit calculates a position of the surveying target unit in consideration of a scanning angle when laser oscillation is confirmed. . The position detector is
Based on the peak position of the spectrum of the light measured by the spectrum measurement unit, the direction of the survey target unit with respect to the surveying unit is detected, and based on the spectrum width of the spectrum of the light measured by the spectrum measurement unit, the surveying The surveying device according to claim 1, wherein a distance between the surveying unit and the surveying target unit is calculated.

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