Reflector, surveying system and control point surveying method

Abstract

A reflector, a surveying system, and a reference point surveying method are provided that are capable of detecting the direction of incidence of a light ray on a reflector, regardless of the direction of incidence of the light ray. [Solution] The device has a prism section 2 that forms a wide-angle prism using multiple prisms 4 arranged at least in a portion of the circumferential direction, and a direction angle detector 3 arranged in a space 5 formed within the prism section. The prisms 4 are configured to reflect a portion of the incident light ray 13 and transmit the remainder, and are arranged alternately in upper and lower rows so that the heights of the corner vertices are different. The direction angle detector 3 includes a first deflection optical element that deflects light rays that have passed through the prisms on the upper row, a second deflection optical element that deflects light rays that have passed through the prisms on the lower row, an imaging lens, and a light receiving sensor, and is configured to output positional information including the prism into which the light ray is incident and the angle of incidence relative to the prism based on the light receiving position of the light receiving sensor of the light ray deflected by the first deflection optical element or the second deflection optical element.

Description

[Technical Field]

[0001] The present invention relates to a reflector that retroreflects a light beam such as a laser beam, a surveying system, and a method for surveying reference points. [Background technology]

[0002] In laser surveying, a reflector that retroreflects the distance measurement light is used as the measurement target. The reflector is attached to a pole that indicates the measurement point, and the reflector is usually a full-circle prism that retroreflects the laser beam over a wide range.

[0003] The full-circumference prism is made up of a combination of multiple corner cube prisms, and in addition to having a complex structure, the retroreflection point (measurement reference point) may shift slightly depending on the direction of the incident light, which can cause measurement errors in distance, vertical angle, and horizontal angle. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Patent No. 6000823 Summary of the Invention [Problem to be solved by the invention]

[0005] The present invention provides a reflector, a surveying system, and a control point surveying method that are capable of detecting the direction of incidence of a light ray on a reflector, regardless of the direction of incidence of the light ray. [Means for solving the problem]

[0006] The present invention relates to a reflector having a prism section that forms a wide-angle prism using a plurality of prisms arranged at least in a portion of the circumferential direction, and a direction angle detector that is arranged in a space formed within the prism section, wherein the prisms are configured to reflect a portion of the incident light rays and transmit the remainder, and the prisms are arranged alternately in upper and lower rows so that the heights of the corner vertices are different, and the direction angle detector includes a first deflection optical element that deflects the light rays that have passed through the prisms on the upper row, a second deflection optical element that deflects the light rays that have passed through the prisms on the lower row, an imaging lens, and a light receiving sensor, wherein the light rays deflected by the first deflection optical element or the second deflection optical element enter the imaging lens and are imaged on the light receiving sensor by the imaging lens, and positional information including the prism into which the light rays have entered and the angle of incidence with respect to the prism is output based on the light receiving position of the light receiving sensor.

[0007] The present invention also relates to a reflector configured so that the light beam incident on the prism is received within a specific area on the light receiving sensor corresponding to each prism.

[0008] The present invention also relates to a reflector in which the prism portion further includes a zenith prism that receives the light beam from the zenith direction.

[0009] The present invention also relates to a reflector in which the direction angle detector further includes a third deflection optical member that deflects only the light beam incident from the zenith prism.

[0010] The present invention also relates to a reflector in which the first deflection optical member and the second deflection optical member are lenses that internally reflect the light beam incident from the side surface multiple times.

[0011] The present invention also relates to a reflector in which the first deflection optical element is a free-form mirror having a free-form reflective surface, and the second deflection optical element is a lens that internally reflects the light rays incident from the side surface multiple times.

[0012] The present invention also relates to a reflector in which the first deflection optical element is a free-form mirror having a free-form reflective surface, the second deflection optical element is a lens that internally reflects the light rays incident from the side multiple times, and the first deflection optical element is formed with a hole through which the light rays incident from the zenith prism pass.

[0013] The present invention also relates to a reflector in which the first deflection optical element is a lens that internally reflects the light rays incident from the side surface multiple times, the second deflection optical element is a free-form surface mirror having a free-form reflective surface, and the second deflection optical element is formed with a hole through which the light rays deflected by the first deflection optical element pass.

[0014] The present invention also relates to a reflector in which the first deflection optical element and the second deflection optical element are free-form mirrors each having a free-form reflective surface, and the second deflection optical element is formed with a hole through which the light beam deflected by the first deflection optical element passes.

[0015] The present invention also relates to a reflector in which the first deflection optical element and the second deflection optical element are free-form mirrors each having a free-form reflective surface, the first deflection optical element has a hole formed therein through which the light rays incident from the zenith prism pass, and the second deflection optical element has a hole formed therein through which the light rays deflected by the first deflection optical element pass.

[0016] The present invention also relates to a surveying system having a target device equipped with the above-mentioned reflector and a surveying instrument capable of measuring the reflector, wherein the target device has a communication unit for transmitting light-receiving position information emitted by the light-receiving sensor to the surveying instrument, and the surveying instrument has in advance table data correlating the incident angle with respect to the prism with the amount of correction for the measurement result, and the surveying system is configured to detect the incident prism and the incident angle with respect to the prism based on the position information received from the target device, and correct the measurement result of the reflector based on the incident angle.

[0017] The present invention also relates to a surveying system in which the target device further comprises a pole that is installed at the measurement point and whose axis passes through the reference point of the reflector, and a tilt detector that can detect the verticality of the pole, and the surveying instrument measures the measurement point based on the measurement result of the reflector and the known distance from the reference point to the bottom end of the pole, and corrects the measurement result of the measurement point based on the angle of incidence with respect to the prism.

[0018] The present invention also relates to a surveying system in which the target device further comprises a pole installed at the measurement point and configured so that its axis passes through the reference point of the reflector, and a tilt detector capable of detecting two-axial tilt of the pole relative to the horizontal, and the surveying instrument measures the measurement point based on the measurement results of the reflector, the detection results of the tilt detector, and the known distance from the reference point to the bottom end of the pole, and corrects the measurement results of the measurement point based on the angle of incidence with respect to the prism.

[0019] The present invention also relates to a surveying system in which the target device further comprises a pole that is installed at the measurement point and whose axis passes through the reference point of the reflector, the direction angle detector functions as a polarized camera that can detect left-right inclination relative to the surveying instrument, the surveying instrument emits distance measuring light of a predetermined polarized light, measures the measurement point based on the measurement results of the reflector, the left-right inclination angle obtained by the polarized camera, the forward-backward inclination angle and direction angle detected based on the angle of incidence to the prism, and the known distance from the reference point to the bottom end of the pole, and corrects the measurement result of the measurement point based on the angle of incidence to the prism.

[0020] The present invention also relates to a surveying system in which the target device is a handheld scanner capable of acquiring point cloud data of the object to be measured, and the handheld scanner further has an inclination detector capable of detecting two-axis inclination relative to the horizontal, and the surveying instrument is capable of converting the point cloud data acquired by the handheld scanner into point cloud data based on the installation position of the surveying instrument based on the measurement results of the reflector and the detection results of the inclination detector, and is configured to correct the point cloud data of the object to be measured based on the angle of incidence with respect to the prism.

[0021] Furthermore, the present invention relates to a control point surveying method using the above-mentioned reflector, in which the above-mentioned reflector is installed at at least known point 2 of known points 1 and 2, a surveying device is installed at new point 1, known points 1 and 2 are measured by the surveying device, new point 1 is made known by resection, the direction angle of new point 1 is detected with the reflector at known point 2, the surveying device is then installed at new point 2, known point 2 is measured from new point 2, the direction angle of new point 2 is detected with the reflector at known point 2, and new point 2 is made known based on the direction angles of new point 1 and new point 2 detected by the reflector and the measurement results of measuring known point 2 from new point 2. [Effects of the Invention]

[0022] According to the present invention, a wide-angle prism is formed by a prism section including a plurality of prisms arranged at least in a portion of the circumferential direction, and a direction angle detector is arranged in a space formed within the prism section, and the prisms are configured to reflect a portion of the incident light beam and transmit the remainder, and the prisms are arranged alternately in upper and lower rows so that the heights of the corner vertices are different, and the direction angle detector includes a first deflection optical member that deflects the light beam that has passed through the prisms on the upper row side, and a second deflection optical member that deflects the light beam that has passed through the prisms on the lower row side. The optical system includes a second deflection optical element that deflects rays, an imaging lens, and a light receiving sensor, and the light ray deflected by the first deflection optical element or the second deflection optical element is incident on the imaging lens, and is imaged by the imaging lens on the light receiving sensor. Positional information including the prism into which the light ray is incident and the angle of incidence relative to the prism is output based on the light receiving position of the light receiving sensor. Therefore, regardless of the direction of incidence on the reflector, the prism into which the light ray is incident and the inclination angle relative to the prism can be detected.

[0023] According to the present invention, there is also provided a surveying system having a target device provided with the above-mentioned reflector and a surveying instrument capable of measuring the reflector, wherein the target device has a communication unit for transmitting light receiving position information emitted by the light receiving sensor to the surveying instrument, and the surveying instrument has in advance table data correlating the incident angle to the prism with the amount of correction for the measurement result, and is configured to detect the incident prism and the incident angle to the prism based on the position information received from the target device, and correct the measurement result of the reflector based on the incident angle, so that measurement results from which errors have been removed can be obtained regardless of the incident direction to the reflector, thereby providing the excellent effect of improving measurement accuracy. [Brief explanation of the drawings]

[0024] [Figure 1] FIG. 2 is a cross-sectional view showing an optical system of a reflector according to the first embodiment. [Figure 2]FIG. 1A is a perspective view of a reflector according to a first embodiment, FIG. 1B is a cross-sectional view of a prism portion, and FIG. 1C is an explanatory diagram illustrating a light-receiving region formed on a light-receiving sensor. [Figure 3] FIG. 2 is a configuration diagram showing an optical system of a direction angle detector according to the first embodiment. [Figure 4] FIG. 4 is an explanatory diagram showing a first surveying method using the reflector. [Figure 5] 10 is a graph showing the relationship between the angle of incidence of the reflector on the prism and the distance correction value. [Figure 6] FIG. 10 is an explanatory diagram showing a second surveying method using the reflector. [Figure 7] FIG. 10(A) is an explanatory diagram showing a third surveying method using the reflector, and FIG. 10(B) is an explanatory diagram explaining a polarized camera. [Figure 8] FIG. 10 is an explanatory diagram showing a fourth surveying method using the reflector. [Figure 9] (A) and (B) are explanatory diagrams of the conventional resection method for measuring new points. [Figure 10] 10(A) and 10(B) are explanatory diagrams showing a fifth surveying method for measuring new points using the reflector. [Figure 11] FIG. 10 is a configuration diagram showing an optical system of a direction angle detector according to a second embodiment. [Figure 12] FIG. 10 is a configuration diagram showing an optical system of a direction angle detector according to a third embodiment. [Figure 13] FIG. 10 is a configuration diagram showing an optical system of a direction angle detector according to a fourth embodiment. [Figure 14] FIG. 10 is a cross-sectional view showing an optical system of a reflector according to a fifth embodiment. [Figure 15] FIG. 10(A) is a perspective view of a reflector according to a fifth embodiment, (B) is a cross-sectional view of a prism portion, and (C) is an explanatory diagram illustrating a light-receiving region formed on a light-receiving sensor. [Figure 16] FIG. 10 is a configuration diagram showing an optical system of a direction angle detector according to a fifth embodiment. [Figure 17] FIG. 10 is a configuration diagram showing an optical system of a direction angle detector according to a sixth embodiment. [Figure 18] FIG. 13 is a configuration diagram showing an optical system of a direction angle detector according to a seventh embodiment. [Figure 19] FIG. 1A is a perspective view showing a modified example of a prism portion according to an embodiment of the present invention, and FIG. 1B is a cross-sectional view of the prism portion. DETAILED DESCRIPTION OF THE INVENTION

[0025] Hereinafter, an embodiment of the present invention will be described with reference to the drawings.

[0026] A reflector 1 according to a first embodiment of the present invention will be described with reference to FIGS.

[0027] The reflector 1 is composed of a prism portion 2 made up of a plurality of prisms, and a direction angle detector 3 for detecting the incident direction of light onto the reflector 1 .

[0028] The prism portion 2 is a full-circumference prism serving as a retroreflector, and as shown in FIG. 2(A), is composed of multiple corner cube prisms 4 arranged at least circumferentially. Each prism 4 has a triangular truncated pyramid shape, for example, with the apex of a regular triangular pyramid removed. In the following description, the light incident surface of the prism 4 is referred to as the lower base surface, and the surface through which light passes after passing through the lower base surface is referred to as the upper base surface. The upper and lower base surfaces are parallel. It is sufficient that only a portion of the light passing through the lower base surface passes through the upper base surface. Therefore, to maximize the efficiency of the transmitted light, the upper base surface is coated with, for example, an AR coating. Alternatively, the upper base surface may be uncoated to reduce costs.

[0029] Of the prisms 4, six prisms 4a to 4f are arranged alternately in the circumferential direction with their lower bases turned upside down. Of the upper and lower recesses formed by the prisms 4a to 4f, one prism 4g as a zenith prism is arranged in the upper recess (zenith side) so that its lower base faces the zenith direction.

[0030] That is, the prism unit 2 is configured to allow light from all around the 360° horizontal direction to be incident on any of the six prisms 4a to 4f and to be retroreflected, and to allow light from above to be incident on the prism 4g and to be retroreflected. Therefore, when an axis (main optical axis O) passing through the centers of the upper and lower base surfaces of the prism 4g is vertical, the prism unit 2 can retroreflect light from all around the 360° horizontal direction and a vertical angle range of about 300° excluding the downward direction.

[0031] Furthermore, by arranging the prisms 4a to 4g as described above, a space 5 corresponding to the removed vertex is formed in the center of the prism portion 2, and the direction angle detector 3 is provided within this space 5.

[0032] As shown in Figures 2(A) and 2(B), of the six prisms 4a to 4f arranged in the circumferential direction, the adjacent prisms 4a and 4b have different heights above and below the apex of the triangular pyramid, i.e., the corner apex, before cutting, and the prism 4b is located below the prism 4a.

[0033] Regarding the relative positions of the other adjacent prisms, the corner apex of prism 4c is located higher than that of prism 4b, the corner apex of prism 4d is located lower than that of prism 4c, the corner apex of prism 4e is located higher than that of prism 4d, the corner apex of prism 4f is located lower than that of prism 4e, and the corner apex of prism 4a is located higher than that of prism 4f. That is, the corner apexes of prisms 4a to 4f are alternately arranged in the upper and lower rows to align the height of their optical centers in the horizontal plane. Here, the optical center refers to a measurement reference point located inside each corner cube prism. Furthermore, the corner apexes of the prisms 4a, 4c, and 4e on the upper row are located at the same height, and the corner apexes of the prisms 4b, 4d, and 4f on the lower row are located at the same height.

[0034] Adjacent prisms 4 are arranged so that their bottom surfaces are upside down and their tilt directions relative to the horizontal are also opposite. As a result, the refraction directions inside the prisms 4 are also opposite, and the horizontal heights of the optical centers A of the prisms 4a, 4c, and 4e on the upper side and the optical centers B of the prisms 4b, 4d, and 4f on the lower side can be aligned. In this case, the center of a circle passing through each optical center, or the center of a circle approximating each optical center, serves as the reference point 1a of the reflector 1.

[0035] In this embodiment, the positions of the corner apexes of adjacent prisms 4, for example, prisms 4a and 4b, are shifted vertically so that the vertical heights of the retroreflected light match, particularly near the horizontal where the reflector 1 is frequently used. Therefore, the reflector 1 is configured so that there is no error in the measured vertical angle near the horizontal, regardless of the prism 4 onto which the light is incident.

[0036] Next, the direction angle detector 3 will be described in detail with reference to Fig. 3. In Fig. 3, the upper side of the paper is referred to as "up", the lower side of the paper is referred to as "down", the right side of the paper is referred to as "right", and the left side of the paper is referred to as "left".

[0037] The direction angle detector 3 has a main optical axis O that passes through the centers of the upper and lower base surfaces of the prism 4g, and is equipped with a first front group lens 6 as a first deflection optical element arranged on the main optical axis O, a second front group lens 7 as a second deflection optical element, an aperture plate 8, a rear group lens 9 as an imaging lens consisting of a group of convex lenses, an external light cut filter 11, and a light receiving sensor 12.

[0038] The first front group lens 6 is, for example, a single concave lens, and has a side surface 6a on which light rays 13 having a predetermined wavelength that have passed through the upper prisms 4a, 4c, and 4e are incident, an upper surface 6b on which light rays 13 that have passed through the zenith-side prism 4g are incident, and a lower surface 6c on which a recess is formed.

[0039] The side surface 6a is, for example, a cylindrical surface coated with an AR (Anti-Reflection) coating, and is configured to allow the incident light ray 13 to be incident on the lower surface 6c at an angle equal to or greater than the critical angle. Note that the side surface 6a is not limited to a cylindrical surface, and may be a toric surface or an axisymmetric free-form surface.

[0040] The upper surface 6b is an axisymmetric free spherical surface, which may be a spherical surface or an aspherical surface, and has an AR coating applied to the center portion and a reflective coating applied to the portion other than the center (periphery). The light ray 13 transmitted through the prism 4g is incident on the AR coated portion in the center, and then passes through the first front lens group 6 to be incident on the lower surface 6c.

[0041] The lower surface 6c is an axisymmetric free-form surface, such as a spherical or aspherical surface, and is entirely AR-coated. The lower surface 6c is configured to totally reflect the light ray 13 incident at an angle equal to or greater than the critical angle, and to totally transmit the light ray 13 incident at an angle less than the critical angle.

[0042] The lower surface 6c may be provided with an AR coating only on the center portion, and the remaining portion may be a beam splitter film that reflects 50% of light and transmits 50% of light. This allows the light ray 13 that has passed through the side surface 6a to be reflected even if the incident angle of the light ray 13 is less than the critical angle, thereby improving the degree of freedom in design.

[0043] The second front group lens 7 is, for example, a single concave lens, and has a side surface 7a on which the light rays 13 that have passed through the lower prisms 4b, 4d, and 4f are incident, an upper surface 7b on which the light rays 13 that have passed through the first front group lens 6 are incident, and a lower surface 7c on which a recess is formed.

[0044] The side surface 7a is, for example, a cylindrical surface with an AR coating, and is configured to make the incident light ray 13 incident on the lower surface 7c at an angle equal to or greater than the critical angle. Note that the side surface 7a is not limited to a cylindrical surface, and may be a toric surface or an axisymmetric free-form surface.

[0045] The upper surface 7b is an axisymmetric free spherical surface, which may be a spherical surface or an aspherical surface, and has an AR coating applied to the center portion and a reflective coating applied to the portion other than the center (periphery). The light ray 13 transmitted through the first front lens group 6 is incident on the AR coated portion in the center, and then passes through the second front lens group 7 to be incident on the lower surface 7c.

[0046] The lower surface 7c is an axisymmetric free-form surface, such as a spherical or aspherical surface, and is entirely AR-coated. The lower surface 7c is configured to totally reflect the light ray 13 incident at an angle equal to or greater than the critical angle and to totally transmit the light ray 13 incident at an angle less than the critical angle. Similarly to the lower surface 6c, the lower surface 7c may be AR-coated only at its center, with the remaining portion being a beam splitter film.

[0047] In the above description, the first front lens group 6 and the second front lens group 7 are single concave lenses, but they may be lens groups each made up of a combination of a plurality of lenses.

[0048] The diaphragm plate 8 is a plate material in which a hole of a predetermined size is formed and centered on the main optical axis O, and it allows only the light rays 13 that pass through the hole to pass through, and blocks the light rays 13 that pass through optical paths other than the hole, i.e., stray light.

[0049] The rear lens group 9 is composed of a plurality of lenses, and forms an image of the light ray 13 that has passed through the hole in the diaphragm plate 8 on the light receiving sensor 12. The external light cut filter 11 is, for example, a band-pass filter or a dichroic filter, and is capable of removing light of wavelengths other than the light ray 13, such as external light.

[0050] The light receiving sensor 12 is a 2D sensor protected by a protective glass 10 and is a collection of pixels. Each pixel has pixel coordinates (x:y) with the main optical axis O as the origin, and the pixel coordinates identify the position on the light receiving sensor 12. Each pixel outputs position information (pixel coordinates) along with a light receiving signal. A 2D image sensor such as a CCD or CMOS is used as the light receiving sensor 12.

[0051] 2(C), the light ray 13 incident on the reflector 1 has a different light receiving position relative to the light receiving sensor 12 depending on the prism 4 into which it is incident. That is, regions 12a to 12g corresponding to the prisms 4a to 4g are formed on the light receiving sensor 12, and the light ray 13 incident on each of the prisms 4a to 4g is incident on the corresponding region 12a to 12g, respectively. In addition, the regions 12a to 12g do not overlap each other on the light receiving sensor 12.

[0052] For example, the light ray 13 incident on the zenith prism 4g is received by a circular region 12g centered on the origin of the light receiving sensor 12. The light ray 13 incident on the upper prisms 4a, 4c, and 4e is received by regions 12a, 12c, and 12e formed to form parts of a ring at predetermined angular intervals within a circular region formed around the region 12g with the origin of the light receiving sensor 12 as its center. The light ray 13 incident on the lower prisms 4b, 4d, and 4f is received by regions 12b, 12d, and 12f formed to form parts of a ring at predetermined angular intervals within a circular region formed around the region 12a, 12c, and 12e with the origin of the light receiving sensor 12 as its center.

[0053] Of the annular regions formed around the region 12g, regions between the regions 12a and 12c, between the regions 12c and 12e, and between the regions 12e and 12a form regions where the light ray 13 is not received. Similarly, of the annular regions formed around the regions 12a, 12c, and 12e, regions between the regions 12b and 12d, between the regions 12d and 12f, and between the regions 12f and 12b form regions where the light ray 13 is not received. Furthermore, the region 12b is formed at a position centered on the region between the regions 12a and 12c and spanning the regions 12a and 12c, the region 12d is formed at a position centered on the region between the regions 12c and 12e and spanning the regions 12c and 12e, and the region 12f is formed at a position centered on the region between the regions 12e and 12a and spanning the regions 12e and 12a.

[0054] Thus, when the light ray 13 is incident on the reflector 1, a part of the light ray 13 is retroreflected, and the remainder is incident on the direction angle detector 3. Furthermore, the direction angle detector 3 can detect from which of the prisms 4a to 4g the light ray 13 is incident, based on which of the areas 12a to 12g on the light receiving sensor 12 the light ray 13 is received, and can also detect at which angle (horizontal angle and vertical angle) the light ray 13 is incident with respect to the prism 4, based on which position (pixel) of the incident areas 12a to 12g the light ray 13 is received.

[0055] In addition, there are cases where the light ray 13 is incident on two or more of the prisms 4a to 4g and is received by two or more of the regions 12a to 12g when it is incident on the vicinity of the boundary between the adjacent prisms 4. However, since the type of image formed on the light receiving sensor 12 can be predicted in advance by design, accurate measurement of horizontal and vertical angles becomes possible by performing calibration in advance at the factory.

[0056] Furthermore, the detection of the prism 4 and the incident angle (horizontal angle and vertical angle) of the light ray 13 may be performed by a surveying device that measures the reflector 1 based on the light receiving signal and position information from the light receiving sensor 12, or by a control device separately provided in the reflector 1, or by a portable terminal (not shown) carried by the operator.

[0057] Furthermore, the entrance pupil positions of the light rays 13 incident on the side surface 6a from the upper prisms 4a, 4c, and 4e are located on the same circumference of a circle centered on the main optical axis O. Therefore, the entrance pupil positions can be moved closer to the prisms 4a, 4c, and 4e. Similarly, the entrance pupil positions of the light rays 13 incident on the side surface 7a from the lower prisms 4b, 4d, and 4f are located on the same circumference of a circle centered on the main optical axis O. Therefore, the entrance pupil positions can be moved closer to the prisms 4b, 4d, and 4f.

[0058] Next, a first surveying method using the reflector 1 will be described with reference to Fig. 4. In the following description, the distance measuring light 22 emitted from the surveying instrument 15 is regarded as the light ray 13 incident on the reflector 1.

[0059] The surveying system 14 includes the surveying device 15 and a target device 16. The surveying device 15 is, for example, a total station capable of measurement (distance measurement and angle measurement) and tracking.

[0060] The target device 16 also includes the reflector 1 supported on a base 17, a pole 18 extending downward from the underside of the base 17 and having a pointed lower end, a tilt detector 19, such as a bubble tube, provided on the base 17, and a communication unit 21 provided on the base 17 and capable of wireless communication with the surveying device 15. Note that a reference point 1a of the reflector 1 is located on the axis of the pole 18, and the distance from the reference point 1a to the lower end of the pole 18 is known.

[0061] When performing a surveying operation using the surveying instrument 15 and the target device 16, first, the surveying instrument 15 is made to emit a distance measuring light 22 of a predetermined wavelength and a tracking light 23 of a wavelength different from the distance measuring light 22, and the reflector 1 is tracked by the tracking light 23. In this state, the target device 16 is carried to a predetermined measurement point 24, and the target device 16 is set so that the measurement point 24 and the lower end of the pole 18 coincide with each other.

[0062] The ranging and tracking instructions may be given from the surveying device 15, or by an operator via a mobile terminal such as a smartphone or tablet (not shown), or instructions may be given from the target device 16 via the communication unit 21.

[0063] Furthermore, after the target device 16 is set to a vertical position based on the tilt detector 19, the surveying device 15 is made to measure the reflector 1. The surveying device 15 emits the distance measuring light 22 and the tracking light 23 coaxially, and measurement is performed in parallel with tracking of the reflector 1.

[0064] The distance measuring light 22 and the tracking light 23 incident on the lower base surface of a predetermined prism 4 of the reflector 1 at a predetermined incident angle pass through the inside of the prism 4 and are incident on the upper base surface. A part of the distance measuring light 22 and the tracking light 23 passes through the upper base surface, and the remaining part is retroreflected by reflection on three surfaces excluding the upper base surface.

[0065] The ranging light 22 and the tracking light 23 that pass through the upper bottom surface are incident on the direction angle detector 3, and the reception result of the ranging light 22 by the direction angle detector 3 is transmitted to the surveying device 15 via the communication unit 21.

[0066] That is, the distance measurement light 22 and the tracking light 23 that have passed through the upper bottom surface are incident on the first front lens group 6 or the second front lens group 7 and are internally reflected, pass through holes in the diaphragm plate 8, and are collected by the rear lens group 9. After the external light cut filter 11 removes external light and the tracking light 23, only the distance measurement light 22 is incident on predetermined pixels in the areas 12a to 12g on the light receiving sensor 12 that correspond to the prisms 4a to 4g.

[0067] In the light receiving sensor 12, the pixel that receives the distance measuring light 22 outputs a light receiving signal and position information (pixel coordinates). The output light receiving signal and position information are transmitted to the surveying instrument 15 via the communication unit 21.

[0068] The regions 12a to 12g that receive the distance measurement light 22 and the positions within the regions 12a to 12g are determined by the prisms 4a to 4g onto which the distance measurement light 22 is incident and the angle of incidence (horizontal angle and vertical angle) relative to the prisms 4a to 4g. That is, if the receiving position of the distance measurement light 22 on the light receiving sensor 12 is known, the prisms 4a to 4g onto which the distance measurement light 22 is incident and the angle of incidence relative to the prisms 4a to 4g can be identified. Therefore, the position information output from the light receiving sensor 12 can be considered as position information including the prisms 4a to 4g onto which the light ray 13 is incident and the angle of incidence relative to the prisms 4a to 4g.

[0069] Based on the detection results of the direction angle detector 3 received from the target device 16, i.e., the light receiving signal and position information, the surveying device 15 identifies the prism 4 from among the prisms 4a to 4g onto which the ranging light 22 is incident, and calculates correction information based on the incident angle (vertical angle and horizontal angle) of the ranging light 22 relative to the prism 4.

[0070] In addition, the surveying device 15 corrects the measurement (distance and angle) results of the reflector 1 based on the obtained correction information, and calculates the three-dimensional coordinates of the measurement point 24 based on the corrected measurement results and the known distance from the reference point 1a of the reflector 1 to the bottom end of the pole 18.

[0071] Here, an error may occur in the measurement result of the reflector 1 depending on the orientation of the reflector 1 with respect to the surveying instrument 15, i.e., on which prism 4 of the reflector 1 the distance measuring light 22 (the tracking light 23) as the light ray 13 is incident, and at what angle (horizontal angle and vertical angle) it is incident on the prism 4. The error at this time can be related to the vertical angle (tilt angle) of the distance measuring light 22 with respect to the horizontal and the horizontal angle (azimuth angle) based on the vertical axis.

[0072] For example, when correcting the distance measurement results, the distance correction amount for each horizontal angle and vertical angle of the reflector 1 is calculated in advance, or the correction amount is actually measured at the factory before shipping, and table data of distance correction amounts that correlates the horizontal angle, vertical angle, and distance correction amount is created in advance.

[0073] 5, the table data can be converted into a function of linear interpolation or quadratic variables, and the distance correction amount, which is correction information when measuring the reflector 1, can be calculated based on the function and the horizontal angle and vertical angle detected by the direction angle detector 3. Furthermore, by correcting the distance measurement result with the calculated distance correction amount, it is possible to obtain distance measurement results without error.

[0074] Similarly, for the horizontal angle and vertical angle, table data of the difference between the actual horizontal angle and vertical angle and the horizontal angle and vertical angle obtained by measurement, i.e., the angle correction amount, can be created in advance by calculation or actual measurement, and the table data can be converted into a function of linear interpolation or quadratic variables, and the angle correction amount, which is the correction information when measuring the reflector 1, can be obtained based on the function and the horizontal angle and vertical angle detected by the direction angle detector 3. In addition, by correcting the angle measurement result, i.e., the horizontal angle and vertical angle, with the obtained angle correction amount, it is possible to obtain an angle measurement result without error.

[0075] Furthermore, based on the corrected distance and angle measurement results and the known distance from the reference point 1a of the reflector 1 to the bottom end of the pole 18, the three-dimensional coordinates of the measurement point 24 can be determined with high accuracy.

[0076] The correction of the measurement results based on the correction information received from the target device 16 may be performed every time the reflector 1 is measured. Alternatively, the measurement results of the reflector 1 and the correction information from the target device 16 may be stored in association with each other, and the measurement results may be corrected after the measurement of all the measurement points 24 is completed. In this case, the measurement results and correction information may be stored in the surveying device 15, or may be stored in a portable terminal (not shown) held by the operator.

[0077] In addition, in the first embodiment, the distance measuring light 22 is used as the light ray 13, but the tracking light 23 may be used as the light ray 13. In other words, any light having a specific wavelength can be used as the light ray 13 in this embodiment.

[0078] As described above, in the first embodiment, the reflector 1 is composed of the prism portion 2, which is composed of multiple triangular truncated pyramidal prisms 4 with their vertices cut off, and the direction angle detector 3, which is provided in the space 5 formed in the prism portion 2 by the cut-out portions, and is configured so that a portion of the light ray 13 incident on the prism portion 2 is incident on the direction angle detector 3.

[0079] In addition, the direction angle detector 3 can identify the prism 4 into which the light ray 13 is incident based on the receiving position of the light ray 13 at the light receiving sensor 12, and can detect the incident angle (horizontal angle and vertical angle) with respect to the prism 4.

[0080] Therefore, the reflector 1 can retroreflect the incident light ray 13 and detect the prism 4 on which the light ray 13 has entered and the angle of incidence of the light ray 13 with respect to the prism 4 .

[0081] In the prism section 2, six prisms 4a to 4f are arranged alternately in the circumferential direction with their lower bases turned upside down, and the prism 4g is arranged in the upper recess formed by the prisms 4a to 4f so that its lower base faces the zenith. Therefore, the reflector 1 can receive and retroreflect the light ray 13 in a range of 360° horizontally and about 300° vertically excluding the downward direction.

[0082] In the first embodiment, the prisms 4 are arranged in the prism section 2 so that the positions of the corner apexes of adjacent prisms 4, 4 are shifted up and down. Therefore, in the vicinity of the horizontal plane where the reflector 1 is frequently used, the height of the retroreflected light ray 13 can be adjusted regardless of the prism 4 on which the light ray 13 is incident, and therefore errors in the vertical angle caused by differences in the prism 4 on which the light ray 13 is incident can be suppressed.

[0083] Furthermore, when performing prism surveying using the reflector 1, the distance and angle errors that occur when measuring the measurement results of the reflector 1 can be corrected based on the correction information received from the direction angle detector 3, so that the errors can be removed from the measurement results and measurement accuracy can be improved.

[0084] Furthermore, since the target device 16 only needs to be installed in a vertical position, there is no need to consider the direction of the reflector 1 relative to the surveying device 15 or the angle of the reflector 1 relative to the surveying device 15, which improves workability in surveying work.

[0085] In the first embodiment, the lower end of the pole 18 is aligned with the measurement point 24, the target device 16 is in a vertical position, and the reflector 1 is measured. However, the surveying method using the reflector 1 is not limited to this.

[0086] 6 shows a second surveying method, in which a tilt detector 25 capable of detecting tilt on two axes, such as a tilt sensor, may be provided on the base 17. By configuring the tilt detector 25 to be capable of detecting tilt on two axes, it becomes possible to measure the reflector 1 without placing the target device 16 in a vertical position.

[0087] That is, in addition to the tilt angle (pitch) in the forward / backward direction relative to the surveying instrument 15 and the tilt angle (roll) in the left / right direction relative to the surveying instrument 15, which can be detected by the tilt detector 25, the direction angle detector 3 detects a direction angle (yaw) that cannot be detected by the tilt detector 25, thereby making it possible to measure the reflector 1. The tilt angle in the forward / backward direction relative to the surveying instrument 15 can also be calculated based on the detection result of the direction angle detector 3 and the vertical angle when the surveying instrument 15 measured the reflector 1.

[0088] Therefore, even when the measurement point 24 is located in a position where the target device 16 cannot be installed in a vertical position, such as in the corner of a room 26, the measurement results can be corrected based on the detection results of the direction angle detector 3 and the tilt detector 25, making it possible to perform highly accurate measurements.

[0089] In the case of the tilt detector 25, it is not possible to determine whether the bottom end of the pole 18 is above or below the reference point 1a of the reflector 1, so when making measurements, it is necessary to separately input the up and down positions relative to the reflector 1.

[0090] 7(A) and 7(B) show a third surveying method, in which a polarization camera may be used to detect the left-right tilt angle (roll) of the target device 16 relative to the surveying device 15. In this case, the light receiving sensor 27 of the direction angle detector 3 is a polarization sensor as shown in Fig. 7(B), and the distance measuring light 22 or the tracking light 23 used as the light beam 13 is polarized light with a predetermined polarization direction.

[0091] The light-receiving sensor 27 has different pixels capable of receiving light depending on the polarization direction of the incident light beam 13. For example, when the polarization direction is 0°, region 27a receives the most light, region 27c receives the least light, and regions 27b and 27d receive half the amount of light received by region 27a (the region with the most light). When the polarization direction of the light beam 13 is perfectly aligned with any of 0°, 45°, 90°, and 135°, light-receiving signals are obtained from three of the regions 27a to 27d. On the other hand, when the polarization direction of the light beam 13 is not perfectly aligned with any of 0°, 45°, 90°, and 135°, light-receiving signals are obtained from all four of the regions 27a to 27d. Therefore, the polarization direction of the light beam 13 can be calculated based on the region from which the light-receiving sensor 27 emits a light-receiving signal and the amount of light received in each region.

[0092] The polarization direction of the light beam 13 incident on the direction angle detector 3 changes depending on the tilt angle (roll) in the left-right direction with respect to the surveying device 15. Therefore, by identifying the areas 27a to 27d from which the light receiving sensor 27 emits a light receiving signal and further calculating the ratio of the amount of light received for each of the areas 27a to 27d, the tilt angle in the left-right direction of the target device 16 can be calculated.

[0093] Furthermore, the direction angle and the tilt angle in the forward and backward directions of the target device 16 can be determined based on the detection result of the direction angle detector 3. Therefore, high-precision measurement with error correction becomes possible without installing the target device 16 in a vertical position.

[0094] When a polarization camera is used, the tilt detector 25 can be omitted. As in the case where the tilt detector 25 is provided, it is necessary to separately input the up and down directions relative to the reflector 1.

[0095] 8 shows a fourth surveying method, in which the reflector 1 may be provided in a portable handheld scanner 28 as a target device, instead of the target device 16. The handheld scanner 28 is capable of acquiring three-dimensional point cloud data of a predetermined measurement object 29 based on the mechanical center of the handheld scanner 28, and is also capable of transmitting the three-dimensional point cloud data to the surveying device 15. The handheld scanner 28 also has a built-in tilt detector (not shown) equivalent to the tilt detector 25, and is capable of detecting two-axial tilt angles relative to the horizontal.

[0096] When the surveying instrument 15 measures the reflector 1, the direction angle (yaw) relative to the surveying instrument 15 can be found based on the detection result of the direction angle detector 3, and the tilt angle relative to the horizontal can be detected by an inclination detector. Therefore, the surveying instrument 15 can calculate three-dimensional point cloud data of the measurement object 29 based on the surveying instrument 15, based on the two-axis tilt angle and direction angle and the measurement result of the reflector 1, and can further calculate highly accurate three-dimensional point cloud data in which errors have been corrected based on the detection result of the direction angle detector 3.

[0097] The surveying device 15 is not limited to a total station, and a laser scanner or a laser tracker may be used. In the case of a conventional laser tracker, it is necessary to provide a light-emitting element such as an LED in the handheld scanner 28, have the laser tracker capture the light from the light-emitting element, and determine the attitude of the handheld scanner 28 based on the position of the light in the image. On the other hand, in the case of this embodiment, the attitude of the handheld scanner 28 can be determined regardless of the orientation of the handheld scanner 28, thereby improving workability.

[0098] 7(A) and 7(B), it is also possible to determine the attitude of the handy scanner 28 based on the detection results of the polarization camera and the direction angle detector 3. In this case, the tilt detector can be omitted.

[0099] Furthermore, by using a color or monochrome sensor as the light receiving sensor 12, the direction angle detector 3 can be a camera that is approximately coaxial with the reflector 1. When a camera is used, the approximate orientation of the surveying instrument 15 relative to the target device 16, i.e., the approximate orientation of the target device 16 relative to the surveying instrument 15, can be determined based on the acquired image.

[0100] Therefore, by transmitting the specified orientation to the surveying device 15 in real time via the communication unit 21, the time it takes for the tracking light 23 to capture the reflector 1 can be shortened, thereby speeding up the surveying work.

[0101] 9(A) and 9(B) show a conventional surveying method, and Fig. 10(A) and Fig. 10(B) show a fifth surveying method. The fifth surveying method is a control point surveying method that uses a laser scanner as the surveying device 15.

[0102] First, a conventional surveying method for performing control point surveying will be described with reference to FIGS. 9(A) and 9(B).

[0103] STEP: 01 Install the surveying device 15 at new point 1, install the reflector 1 at known point 1 and known point 2, measure known point 1 and known point 2 using the surveying device 15, determine the coordinates of new point 1 by intersection, and make new point 1 known. The point that has been made known is called known point 3.

[0104] STEP:02 Install the surveying device 15 at new point 2, leave the reflective target at known point 2 as it is, and install a reflective target at known point 3. Use the surveying device 15 to measure known points 2 and 3 from new point 2, and make new point 2 known in the same way as in STEP:01.

[0105] Next, a control point surveying method of the present invention using the reflector 1 of the above embodiment will be described with reference to FIGS. 10(A) and 10(B).

[0106] STEP 11: The surveying device 15 is installed at new point 1, a reflective target is installed at known point 1, the reflector 1 (including direction angle detector 3) of the present invention is installed at known point 2, and the coordinates of new point 1 are obtained by the method of intersection to make new point 1 known. The known new point 1 is made known point 3.

[0107] STEP 12 At this time, the direction angle detector 3 of the reflector 1 receives the distance measuring light 22 and detects the direction angle of the installation point (known point 3) of the surveying instrument 15 from the light reception result. The direction angle (horizontal angle) at this time is defined as A.

[0108] STEP 13: The surveying instrument 15 is moved to the next measurement point (new point 2) and installed at new point 2. At this time, the reflector 1 at known point 2 is kept in the initial installation state.

[0109] STEP 14: Known point 2 is measured from new point 2 using the surveying device 15. The reflector 1 (direction angle detector 3) receives the distance measuring light 22 and detects the direction angle (horizontal angle) B of new point 2 from known point 2 based on the received light. The horizontal angle C between known point 3 and new point 2 is calculated as (BA).

[0110] From this horizontal angle C and the measurement result of known point 2 by the surveying instrument 15 of new point 2, new point 2 is made known.

[0111] In this embodiment, when making new point 2 known, there is no need to set a target at known point 3, thereby reducing the measurement time. Also, since the measurement result can be corrected based on the detection result of the direction angle detector 3, it is possible to perform highly accurate measurements with errors removed.

[0112] Next, a reflector 31 according to a second embodiment of the present invention will be described with reference to Fig. 11. In Fig. 11, the same components as those in Fig. 3 are given the same reference numerals, and their description will be omitted.

[0113] In the second embodiment, a third front group lens 33 is added as a third deflection optical member to the direction angle detector 32. The other configuration is the same as that of the reflector 1 in the first embodiment, and a part of the light ray 13 incident on the reflector 31 is retroreflected, and the rest is incident on the direction angle detector 32.

[0114] The third front group lens 33 is disposed on the opposite side of the first front group lens 6 from the light receiving sensor 12, and is configured so that only the light ray 13 incident from the prism 4g located at the zenith is incident on the third front group lens 33.

[0115] That is, the light ray 13 transmitted through the upper prisms 4a, 4c, and 4e first enters the first front lens group 6, is internally reflected by the first front lens group 6 multiple times, then passes through the second front lens group 7, the rear lens group 9, etc., and is received by the light receiving sensor 12. Meanwhile, the light ray 13 transmitted through the lower prisms 4b, 4d, and 4f first enters the second front lens group 7, is internally reflected by the second front lens group 7 multiple times, then passes through the rear lens group 9, etc., and is received by the light receiving sensor 12. Furthermore, the light ray 13 transmitted through the zenith prism 4g first enters the third front lens group 33, then passes through the first front lens group 6, the second front lens group 7, the rear lens group 9, etc., and is received by the light receiving sensor 12.

[0116] The light ray 13 is incident on a predetermined position in the regions 12a to 12g corresponding to the prisms 4a to 4g on the light receiving sensor 12. The light receiving sensor 12 generates a light receiving signal and position information in response to receiving the light ray 13. Furthermore, based on the position information, it is possible to detect which of the prisms 4a to 4g the light ray 13 is incident on and at what angle.

[0117] In the second embodiment, the third front group lens 33 is provided onto which only the light ray 13 incident from the prism 4g arranged in the zenith direction is incident, so that it is not necessary to adjust the entrance pupil position of the light ray 13 incident from the prisms 4a, 4c, 4e on the upper side and the light ray 13 incident from the prism 4g on the zenith side using only the first front group lens 6.

[0118] Therefore, it is possible to easily adjust the entrance pupil position of the light ray 13 incident from the prism 4g by design, and the aberration correction accuracy can be improved compared to when only the first front group lens 6 is used, so the reachable distance of the light ray 13 in the zenith direction can be extended, and workability can be improved.

[0119] Next, a reflector 34 according to a third embodiment of the present invention will be described with reference to Fig. 12. In Fig. 12, the same components as those in Fig. 11 are given the same reference numerals, and their description will be omitted.

[0120] In the third embodiment, the direction angle detector 35 has a first perforated free-form surface mirror 36 as a first deflection optical member instead of the first front group lens 6 in the second embodiment. The other configuration is the same as that of the reflector 31 in the second embodiment, and a part of the light ray 13 incident on the reflector 34 is retroreflected, and the rest is incident on the direction angle detector 35.

[0121] The first perforated free-form surface mirror 36 has a hole 36a formed in the center, and the hole 36a is larger than the beam diameter of the light ray 13 that has passed through the third front-group lens 33, and is configured to pass the light ray 13. The first perforated free-form surface mirror 36 is also configured to reflect the light ray 13 that has entered from and passed through the upper-stage prisms 4a, 4c, and 4e toward the second front-group lens 7 by a reflecting surface 36b formed on the lower surface around the hole 36a.

[0122] That is, the light ray 13 that has passed through the upper prisms 4a, 4c, and 4e is reflected by the reflecting surface 36b of the first perforated free-form surface mirror 36, and then passes through the second front lens group 7, the rear lens group 9, etc., before being received by the light receiving sensor 12. Meanwhile, the light ray 13 that has passed through the lower prisms 4b, 4d, and 4f first enters the second front lens group 7, is internally reflected by the second front lens group 7 multiple times, and then passes through the rear lens group 9, etc., before being received by the light receiving sensor 12. Furthermore, the light ray 13 that has passed through the zenith prism 4g first enters the third front lens group 33, passes through the hole 36a, and passes through the second front lens group 7, the rear lens group 9, etc., before being received by the light receiving sensor 12.

[0123] The light ray 13 is incident on a predetermined position in the regions 12a to 12g corresponding to the prisms 4a to 4g on the light receiving sensor 12. The light receiving sensor 12 generates a light receiving signal and position information in response to receiving the light ray 13. Furthermore, based on the position information, it is possible to detect which of the prisms 4a to 4g the light ray 13 is incident on and at what angle.

[0124] In the third embodiment, the first perforated free-form surface mirror 36 is used instead of a lens as the first deflection optical element for reflecting the light ray 13 that has passed through the upper prisms 4a, 4c, and 4e, thereby reducing production costs.

[0125] Also in the third embodiment, the third front group lens 33 makes it possible to easily adjust the entrance pupil position of the light ray 13 incident from the prism 4g, thereby improving the accuracy of aberration correction and extending the reach of the light ray 13 in the zenith direction, thereby improving workability.

[0126] Next, a reflector 37 according to a fourth embodiment of the present invention will be described with reference to Fig. 13. In Fig. 13, the same components as those in Fig. 12 are given the same reference numerals, and their description will be omitted.

[0127] In the fourth embodiment, a direction angle detector 38 has a second perforated free-form surface mirror 39 as a second deflection optical member instead of the second front group lens 7 in the third embodiment. The other configuration is the same as that of the reflector 34 in the third embodiment, and a part of the light ray 13 incident on the reflector 37 is retroreflected, and the rest is incident on the direction angle detector 38.

[0128] The second perforated free-form surface mirror 39 has a hole 39a formed in the center, and the hole 39a is larger than the diameter of the beam of the light ray 13 that has passed through the hole 36a of the first perforated free-form surface mirror 36 and the light ray 13 that has been reflected by the reflecting surface 36b, and is configured to pass the light ray 13. The second perforated free-form surface mirror 39 is also configured to reflect the light ray 13 that has entered from and passed through the lower prisms 4b, 4d, and 4f toward the rear lens group 9 by the reflecting surface 39b formed on the lower surface around the hole 39a.

[0129] That is, the light ray 13 transmitted through the upper prisms 4a, 4c, and 4e is reflected by the reflecting surface 36b of the first perforated free-form surface mirror 36, then passes through the hole 39a, and passes through the rear lens group 9 and the like before being received by the light-receiving sensor 12. Meanwhile, the light ray 13 transmitted through the lower prisms 4b, 4d, and 4f is reflected by the reflecting surface 39b of the second perforated free-form surface mirror 39, then passes through the rear lens group 9 and the like before being received by the light-receiving sensor 12. Furthermore, the light ray 13 transmitted through the zenith prism 4g first enters the third front lens group 33, passes through the holes 36a and 39a, and passes through the rear lens group 9 and the like before being received by the light-receiving sensor 12.

[0130] The light receiving sensor 12 emits a light receiving signal and position information corresponding to the position where the light ray 13 is received, and based on the position information, it can detect the prism 4 where the light ray 13 is incident and the angle of incidence at that time.

[0131] In the fourth embodiment, not only the first deflection optical member but also the second deflection optical member is the second perforated free-form surface mirror 39, which makes it possible to further reduce manufacturing costs.

[0132] Next, a reflector 41 according to a fifth embodiment of the present invention will be described with reference to Figures 14 to 16. In Figures 14 to 16, the same reference numerals are used to designate the same components as those in Figures 1 to 3, and their description will be omitted.

[0133] The reflector 41 of the fifth embodiment has a prism section 42 made up of six prisms 4a to 4f, and does not have the prism 4g arranged in the zenith direction in the first embodiment. The other configurations are the same as those of the first embodiment.

[0134] Although the reflector 41 does not have the prism 4g arranged in the zenith direction, the prisms 4a to 4f can ensure a vertical angle of approximately ±70° at most when the main optical axis O is vertical, except in the zenith direction and downward.

[0135] Moreover, the areas on the light receiving sensor 12 corresponding to the prisms 4a to 4f are areas 12a to 12f as shown in FIG. 15(C), and there is no circular area 12g centered on the origin as in the first embodiment.

[0136] In the fifth embodiment, the light ray 13 transmitted through the upper prisms 4a, 4c, and 4e first enters the first front lens group 6, is internally reflected by the first front lens group 6 multiple times, then passes through the second front lens group 7, the rear lens group 9, etc., and is received by areas 12a, 12c, and 12e on the light-receiving sensor 12. Meanwhile, the light ray 13 transmitted through the lower prisms 4b, 4d, and 4f first enters the second front lens group 7, is internally reflected by the second front lens group 7 multiple times, then passes through the rear lens group 9, etc., and is received by areas 12b, 12d, and 12f on the light-receiving sensor 12.

[0137] The light receiving sensor 12 emits a light receiving signal and position information corresponding to the light receiving position, and based on the position information, it can detect which of the prisms 4a to 4f the light ray 13 is incident on and at what angle.

[0138] Next, a reflector 43 according to a sixth embodiment of the present invention will be described with reference to Fig. 17. In Fig. 17, the same components as those in Fig. 14 are given the same reference numerals, and their description will be omitted.

[0139] In the sixth embodiment, a direction angle detector 44 has a free-form surface mirror 45 as a first deflection optical member instead of the first front lens group 6 in the fifth embodiment. The other configurations are the same as those of the fifth embodiment.

[0140] The free-form surface mirror 45 has a free-form reflecting surface 45a formed on its lower surface, and is configured to reflect the light ray 13 incident on and transmitted through the upper prisms 4a, 4c, and 4e by this reflecting surface 45a toward the second front group lens 7.

[0141] That is, the light ray 13 that has passed through the upper prisms 4a, 4c, and 4e is reflected by the reflecting surface 45a of the free-form surface mirror 45, and then passes through the second front lens group 7, the rear lens group 9, etc., and is received by areas 12a, 12c, and 12e on the light-receiving sensor 12. Meanwhile, the light ray 13 that has passed through the lower prisms 4b, 4d, and 4f first enters the second front lens group 7, is internally reflected by the second front lens group 7 multiple times, and then passes through the rear lens group 9, etc., and is received by areas 12b, 12d, and 12f on the light-receiving sensor 12.

[0142] The light receiving sensor 12 emits a light receiving signal and position information corresponding to the light receiving position, and based on the position information, it can detect which of the prisms 4a to 4f the light ray 13 is incident on and at what angle.

[0143] Furthermore, by using the free-form surface mirror 45 as the first deflection optical member, the cost of parts can be reduced, and the manufacturing cost can be reduced.

[0144] Next, a reflector 46 according to a seventh embodiment of the present invention will be described with reference to Fig. 18. In Fig. 18, the same components as those in Fig. 17 are given the same reference numerals, and their description will be omitted.

[0145] In the seventh embodiment, a direction angle detector 47 has a perforated free-form surface mirror 48 as a second deflection optical member instead of the second front lens group 7 in the sixth embodiment. The other configurations are the same as those of the reflector 43 in the sixth embodiment.

[0146] The perforated free-form surface mirror 48 has a hole 48a formed in the center thereof, and the hole 48a is larger than the diameter of the beam of the light ray 13 reflected by the reflecting surface 45a of the free-form surface mirror 45, and is configured to pass the light ray 13. The perforated free-form surface mirror 48 is also configured to reflect the light ray 13, which has been incident on and passed through the lower prisms 4b, 4d, and 4f, towards the rear lens group 9, by a reflecting surface 48b formed on the lower surface around the hole 48a.

[0147] That is, the light ray 13 transmitted through the upper prisms 4a, 4c, and 4e is reflected by the reflecting surface 45a of the free-form surface mirror 45, passes through the hole 48a, and is transmitted through the rear lens group 9 and the like to be received by areas 12a, 12c, and 12e on the light-receiving sensor 12. In addition, the light ray 13 transmitted through the lower prisms 4b, 4d, and 4f is reflected by the reflecting surface 48b of the perforated free-form surface mirror 48, and is transmitted through the rear lens group 9 and the like to be received by areas 12b, 12d, and 12f on the light-receiving sensor 12.

[0148] The light receiving sensor 12 emits a light receiving signal and position information corresponding to the light receiving position, and based on the position information, it can detect which of the prisms 4a to 4f the light ray 13 is incident on and at what angle.

[0149] Furthermore, by using the perforated free-form surface mirror 48 as the second deflection optical member in addition to the first deflection optical member, the cost of parts can be further reduced, and the manufacturing cost can be further reduced.

[0150] It goes without saying that the first to fifth surveying methods can be implemented even when using the reflectors of the second to seventh embodiments.

[0151] Furthermore, in the first to seventh embodiments, the full-circumference prism is formed by at least six prisms in the shape of a truncated quadrangular pyramid, but the number of prisms is not limited to six.

[0152] 19(A), a regular octahedron full-circumference prism may be formed using eight truncated quadrangular pyramidal prisms 4 as the prism section 51. In this case, as shown in FIG. 19(B), a direction angle detector is placed in the space 5 formed inside, and the light beam 13 incident from the upper four prisms 4 is deflected by the first polarizing optical member, and the light beam 13 incident from the lower four prisms 4 is deflected by the second deflecting optical member, and is received by the light-receiving sensor 12.

[0153] All of the direction angle detectors in the first to seventh embodiments can be applied as the direction angle detector arranged in the space 5. In Fig. 19(B), the direction angle detector 3 in the first embodiment is shown as an example.

[0154] In the above configuration, the prism can be easily arranged and manufactured. In addition, the prism structure has high symmetry, so the direction angle detector can be easily arranged, improving workability.

[0155] Furthermore, in the first to seventh embodiments and their modifications, the full-circumference prism (prism portion) is formed by at least six prisms arranged in the circumferential direction, but the prism portion of the reflector of the present invention is not limited to a full-circumference prism. For example, the full-circumference prism may be formed by four prisms arranged in the circumferential direction, or may be formed by eight prisms arranged in the circumferential direction. In other words, a full-circumference prism may be formed by multiple (at least two or more) prisms arranged in the circumferential direction, and this can be applied to the reflectors in the first to seventh embodiments.

[0156] Furthermore, the prism portion is not limited to a full-circumferential prism. For example, in the first to seventh embodiments, one prism may be removed from the six circumferentially arranged prisms, leaving five circumferentially arranged prisms to form a wide-angle prism, and this wide-angle prism may be applied to the reflectors in the first to seventh embodiments. Here, wide angle means, for example, a range of 120° to 315°. The wide-angle prism may be formed of four or fewer circumferentially arranged prisms, or may be formed of seven or more circumferentially arranged prisms. In other words, a wide-angle prism may be formed of multiple (at least two or more) circumferentially arranged prisms, and may be applied to the reflectors in the first to seventh embodiments. [Explanation of symbols]

[0157] 1 reflector 2 Prism section 3-direction angle detector 6. First front lens group 7. Second front lens group 12 Light receiving sensor 13 rays of light 31 Reflector 34 Reflector 37 Reflector 41 Reflector 43 Reflector 46 Reflector

Claims

1. a prism section that forms a wide-angle prism using a plurality of prisms arranged at least in a portion of the circumferential direction, and a direction angle detector that is arranged in a space formed within the prism section, wherein the prisms are configured to reflect a portion of incident light rays and transmit the remainder, and the prisms are arranged alternately in upper and lower rows so that the heights of the corner vertices are different, and the direction angle detector includes a first deflection optical element that deflects the light rays that have passed through the prisms on the upper row, a second deflection optical element that deflects the light rays that have passed through the prisms on the lower row, an imaging lens, and a light receiving sensor, wherein the light rays deflected by the first deflection optical element or the second deflection optical element are incident on the imaging lens and are imaged on the light receiving sensor by the imaging lens, and positional information including the prism into which the light rays have been incident and the angle of incidence with respect to the prism is output based on the light receiving position of the light receiving sensor.

2. 2. The reflector according to claim 1, wherein the light beam incident on the prism is received within a specific area on the light receiving sensor corresponding to each prism.

3. The reflector according to claim 1 , wherein the prism portion further comprises a zenith prism that receives the light beam from a zenith direction.

4. 4. The reflector according to claim 3, wherein the direction angle detector further comprises a third deflection optical member that deflects only the light beam incident from the zenith prism.

5. 5. The reflector according to claim 1, wherein the first deflection optical member and the second deflection optical member are lenses that internally reflect the light beam incident from a side surface multiple times.

6. 3. The reflector according to claim 1, wherein the first deflection optical element is a free-form mirror having a free-form reflective surface, and the second deflection optical element is a lens that internally reflects the light beam incident from a side surface multiple times.

7. A reflector as described in claim 3 or claim 4, wherein the first deflection optical element is a free-form mirror having a free-form reflective surface, the second deflection optical element is a lens that internally reflects the light rays incident from the side multiple times, and the first deflection optical element has a hole formed therein through which the light rays incident from the zenith prism pass.

8. The reflector according to any one of claims 1 to 4, wherein the first deflection optical element is a lens that internally reflects the light beam incident from the side surface multiple times, the second deflection optical element is a free-form surface mirror having a free-form reflective surface, and the second deflection optical element is formed with a hole through which the light beam deflected by the first deflection optical element passes.

9. 3. The reflector according to claim 1, wherein the first deflection optical member and the second deflection optical member are free-form mirrors each having a free-form reflective surface, and the second deflection optical member has a hole formed therein through which the light beam deflected by the first deflection optical member passes.

10. A reflector as described in claim 3 or claim 4, wherein the first deflection optical element and the second deflection optical element are free-form mirrors each having a free-form reflective surface, the first deflection optical element has a hole formed therein through which the light rays incident from the zenith prism pass, and the second deflection optical element has a hole formed therein through which the light rays deflected by the first deflection optical element pass.

11. A surveying system having a target device provided with the reflector of claim 1 and a surveying instrument capable of measuring the reflector, wherein the target device has a communication unit for transmitting light receiving position information emitted by the light receiving sensor to the surveying instrument, the surveying instrument has in advance table data correlating the incident angle with respect to the prism with the amount of correction for the measurement result, and the surveying system is configured to detect the incident prism and the incident angle with respect to the prism based on the position information received from the target device, and correct the measurement result of the reflector based on the incident angle.

12. The surveying system according to claim 11, wherein the target device further comprises a pole that is installed at the measurement point and whose axis passes through the reference point of the reflector, and a tilt detector that can detect the verticality of the pole, and the surveying instrument is configured to measure the measurement point based on the measurement result of the reflector and the known distance from the reference point to the bottom end of the pole, and to correct the measurement result of the measurement point based on the angle of incidence with respect to the prism.

13. The surveying system according to claim 11, wherein the target device further comprises a pole that is installed at the measurement point and whose axis passes through a reference point of the reflector, and an inclination detector that can detect two-axial inclination of the pole with respect to the horizontal, and the surveying instrument is configured to measure the measurement point based on the measurement result of the reflector, the detection result of the inclination detector, and the known distance from the reference point to the bottom end of the pole, and to correct the measurement result of the measurement point based on the angle of incidence with respect to the prism.

14. 12. The surveying system according to claim 11, wherein the target device further comprises a pole installed at the measurement point and configured so that its axis passes through the reference point of the reflector, the direction angle detector functions as a polarized camera capable of detecting tilt in the left and right directions relative to the surveying instrument, the surveying instrument emits distance measuring light of a predetermined polarized light, measures the measurement point based on the measurement results of the reflector, the left and right tilt angle obtained by the polarized camera, the forward and backward tilt angle and direction angle detected based on the angle of incidence to the prism, and the known distance from the reference point to the bottom end of the pole, and corrects the measurement result of the measurement point based on the angle of incidence to the prism.

15. The surveying system according to claim 11, wherein the target device is a handheld scanner capable of acquiring point cloud data of the object to be measured, the handheld scanner further having an inclination detector capable of detecting inclination of two axes relative to the horizontal, and the surveying instrument is configured to convert the point cloud data acquired by the handheld scanner into point cloud data based on the installation position of the surveying instrument based on the measurement results of the reflector and the detection results of the inclination detector, and to correct the point cloud data of the object to be measured based on the angle of incidence with respect to the prism.

16. A control point surveying method using the reflector of claim 1, comprising the steps of: installing the reflector of claim 1 at at least known point 2 of known points 1 and 2; installing a surveying instrument at new point 1; measuring known points 1 and 2 with the surveying instrument; making new point 1 known by resection; detecting a direction angle of new point 1 with a reflector at known point 2; installing the surveying instrument at new point 2; measuring known point 2 from new point 2; detecting a direction angle of new point 2 with a reflector at known point 2; and making new point 2 known based on the direction angle of new point 1 and the direction angle of new point 2 detected by the reflector and the measurement results of measuring known point 2 from new point 2.

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