Retroreflectors

Patent metadata

Field	Value
Publication number	US-11619491-B2
Application number	US-202016914289-A
Country	US
Kind code	B2
Filing date	Jun 27, 2020
Priority date	Jun 27, 2019
Publication date	Apr 4, 2023
Grant date	Apr 4, 2023

Abstract

A reflector arrangement for determining the position or marking of target points, having at least one retroreflector, and a beam detection unit, by means of which the orientation measurement radiation passing through the retroreflector is acquirable. The beam detection unit comprises a first sensor for generating a signal in dependence on an acquisition of orientation measurement radiation and a first beam guiding unit. The first sensor and the first beam guiding unit are arranged such that a detection field of view for acquiring the orientation measurement radiation is defined, an alignment of the detection field of view around the yaw axis is variable and orientation measurement radiation passing through the retroreflector is acquirable in dependence on the alignment of the detection field of view with the first sensor.

First claim

What is claimed:

1. A reflector arrangement for determining the position or marking of target points for industrial or geodetic surveying, the reflector arrangement comprising:
one retroreflector, which
provides a position determination for the reflector arrangement by means of parallel or coaxial, measurement beam reflection,
provides a passage surface for at least a part of measurement radiation entering the retroreflector as orientation measurement radiation, and
provides a reflector field of view having a first aperture angle around a yaw axis and a second aperture angle around a pitch axis orthogonal to the yaw axis, and

a beam detection unit, by means of which the orientation measurement radiation passing through the retroreflector is acquirable,

wherein a spatial orientation of the reflector arrangement is at least partially definable with the aid of an orientation of a body-intrinsic coordinate system defined by at least the yaw axis in relation to an external coordinate system at least with the aid of a relative yaw angle, wherein the yaw angle specifies a rotational alignment of the reflector arrangement around the yaw axis, wherein the beam detection unit comprises
a first sensor for generating a signal in dependence on an acquisition of orientation measurement radiation and
a first beam guiding unit,

wherein the first sensor and the first beam guiding unit are arranged in such a way that
a detection field of view for acquiring the orientation measurement radiation is defined by an interaction of the beam guiding unit and the sensor, which field of view has an aperture angle around the yaw axis which is less than the first aperture angle of the reflector field of view,
an alignment of the detection field of view around the yaw axis is variable by means of a pivot or rotation of the beam guiding unit around the yaw axis, and
orientation measurement radiation passing through the retroreflector is acquirable in dependence on the alignment of the detection field of view using the first sensor, wherein the first beam guiding unit defines a rotational axis, aligned coaxially or in parallel to the yaw axis, wherein the beam guiding unit is rotatably mounted around the rotational axis for variation of the alignment of the detection field of view and provides a rotation-angle-dependent acquisition of the orientation measurement radiation.

2. The reflector arrangement according to claim 1 , wherein the beam guiding unit comprises at least one beam passage, which beam passage is embodied as an oblong aperture arranged extending in parallel to the yaw axis or is slotted.

3. The reflector arrangement according to claim 1 , wherein the reflector arrangement or the beam guiding unit comprises a beam deflector designed and arranged for deflecting and/or focusing the radiation onto the first sensor, said radiation passing through the passage surface.

4. The reflector arrangement according to claim 1 , wherein the first sensor is designed for generating the signal:
depending on a detection of the orientation measurement radiation, or
depending on an intensity of orientation measurement radiation incident on the first sensor.

5. The reflector arrangement according to claim 1 , further comprising:
a drive unit, which provides a controlled pivot and/or rotation of the beam guiding unit around the rotational axis or yaw axis; or
an encoder unit, which is designed to acquire the alignment of the detection field of view, wherein the encoder unit is coupled to the beam guiding unit, the drive unit, or the rotational axis.

6. The reflector arrangement according to claim 1 , further comprising an analysis unit configured to determine the alignment of the detection field of view in dependence on a signal from the first sensor, wherein the analysis unit is configured such that:
a. by means of the first sensor, an intensity-dependent signal curve is acquirable or during a rotation of the beam guiding unit, a signal intensity is determinable or storable depending on a respective yaw alignment of the beam guiding unit,
b. the yaw angle is derivable based on the determination of the alignment of the detection field of view, or
c. a pitch angle is derivable based on a time or rotation-angle-related distance of two measurement signal acquisitions during a rotation of the beam guiding unit of less than 360°.

7. The reflector arrangement according to claim 1 , wherein the retroreflector is designed as a prism, and the prism comprises:
i. a light entry surface forming a polygon, and
ii. the passage surface opposite to the light entry surface as an aperture,

wherein:
the passage surface is formed at a corner of the prism, wherein the passage surface is formed by an omitted corner of the prism and also defines a polygon, or
the retroreflector defines an optical axis, wherein the optical axis extends orthogonally to the passage surface or intersects the center point of the passage surface.

8. The reflector arrangement according to claim 7 , being designed as a 360° retroreflector having a plurality of retroreflectors which adjoin one another, wherein:
i. the plurality of the prisms are arranged in a ring shape, and
ii. the 360° retroreflector defines an overall field of view around the yaw axis of 360°, wherein the optical axes of at least two prisms have a shared point of intersection with the yaw axis.

9. The reflector arrangement according to claim 8 , wherein the plurality of the retroreflectors is arranged such that:
a. the reflector arrangement comprises a central outlet, wherein the yaw axis extends centrally through the outlet,
b. the beam detection unit is at least partially arranged in the outlet, and
c. the beam detection unit is designed for angle-of-incidence- dependent acquisition of the orientation measurement radiation passing through an arbitrary one of the passage surfaces of the retroreflectors over the overall field of view of 360°.

10. The reflector arrangement according to claim 1 , wherein the beam detection unit comprises a second beam guiding unit and a second sensor, wherein the first beam guiding unit is associated with a first prism group and the second beam guiding unit is associated with a second prism group, wherein:
a. the first and the second prism groups each comprise three prisms, or
b. the first and the second beam guiding unit are arranged in the outlet.

11. The reflector arrangement according to claim 10 , wherein:
a. the first prism group and the first beam guiding unit provide an acquisition of the orientation measurement radiation, which can be provided by the first prism group and is projectable by means of the first beam guiding unit on the first sensor, by the first sensor,
b. the second prism group and the second beam guiding unit provide an acquisition of the orientation measurement radiation, which can be provided by the second prism group and is projectable by means of the second beam guiding unit on the second sensor, by the second sensor, and
c. the center points of the passage surfaces of the prisms of the first prism group are in a first plane, the center points of the passage surfaces of the prisms of the second prism group are in a second plane and the first plane and the second plane are aligned in parallel to one another and have a defined distance, wherein the planes are substantially orthogonal to the yaw axis or the prisms of the first prism group and prisms of the second prism group are tilted oppositely in relation to a plane aligned orthogonally to the yaw axis.

12. The reflector arrangement according to claim 1 , wherein the beam detection unit comprises a second beam

Assignees

• Hexagon Technology Ct Gmbh

Inventors

• Jensen Thomas
• Yang Zheng
• Schwendener Andreas
• Brühlmann Danick
• MüLLER JOSEF
• Stigwall Johan

Classifications

• G02B5/124 Primary

  plural reflecting elements forming part of a unitary plate or sheet · CPC title

• G01C15/002

  Active optical surveying means (optical plumbing G01C15/105) · CPC title

• G01C15/06

  Surveyors' staffs; Movable markers · CPC title

• G02B3/06

  with cylindrical or toric faces · CPC title

• G01C15/004 Primary

  Reference lines, planes or sectors · CPC title