Retroreflector with sensor

Patent metadata

Field	Value
Publication number	US-11656338-B2
Application number	US-201916576699-A
Country	US
Kind code	B2
Filing date	Sep 19, 2019
Priority date	Sep 20, 2018
Publication date	May 23, 2023
Grant date	May 23, 2023

Abstract

A reflector arrangement having at least one retroreflector and at least one sensor arrangement arranged downstream of the retroreflector in relation to a beam incidence direction, having a sensor. The sensor arrangement comprises a code element—having a code pattern, and the retroreflector, the code element—and the sensor are arranged in such a way that the code element—is arranged between the retroreflector and the sensor and an angle-dependent position with respect to the optical axis of a projection of the code pattern onto the detection surface can be determined by means of the sensor.

First claim

What is claimed is:

1. A reflector arrangement for position determination or marking target points, the reflector arrangement comprising:
at least one retroreflector, which
provides position determination for the reflector arrangement by means of parallel measurement beam reflection, and
provides a passage surface for at least a part of measurement radiation entering the retroreflector, and

at least one sensor arrangement, arranged downstream of the retroreflector in relation to a measurement beam incidence direction, the sensor arrangement having a sensor for recording measurement radiation passing through the passage surface, the sensor defining an optical axis oriented orthogonally with respect to its detection surface,
wherein:
the sensor arrangement includes a code element having a code pattern, and
the retroreflector, the code element, and the sensor being arranged such that:
the code element is arranged between the retroreflector and the sensor, and
an angle-dependent position with respect to the optical axis of a projection of the code pattern onto the detection surface can be determined by means of the sensor,
wherein the retroreflector is configured as a prism, and the prism comprises:
a light entry surface forming a triangle and,
as an aperture, the passage surface opposite the light entry surface,

wherein the reflector arrangement is configured as a 360° retroreflector having a multiplicity of retroreflector and sensor arrangement pairs, each having a retroreflector and a sensor arrangement as specified above, with
the multiplicity of retroreflectors being arranged next to one another and being configured as prisms,
the multiplicity of retroreflectors numerically corresponding to the number of sensor arrangements, and
each sensor arrangement being assigned to a retroreflector,

wherein:
the multiplicity of retroreflector and sensor arrangement pairs are arranged annularly, and
the 360° retroreflector defines an overall azimuth field of view of 360°, each of the retroreflector and sensor arrangement pairs covering a part of the overall field of view,

wherein:
a central axis A defined by the annular arrangement of the prisms extends orthogonally with respect to the optical axes of the sensors, and
the optical axes of at least two prisms have a common point of intersection with the central axis A, the position of an optical axis of a prism being defined by the respective midpoints of its light entry surface and of its passage surface.

2. The reflector arrangement according to claim 1 , wherein:
the code element is configured as a photomask and is connected to the passage surface of the retroreflector, and
the code pattern is provided by one or more light transmission regions provided by the photomask.

3. The reflector arrangement according to claim 2 , wherein the photomask comprises a multiplicity of randomly arranged light-transmitting gaps, and the code pattern is provided by said gaps.

4. The reflector arrangement according to claim 1 , wherein the sensor arrangement comprises a separating piece, which is arranged between the code element and the sensor or between the passage surface and the code element, the separating piece being configured as a bandpass filter or as a longpass filter.

5. The reflector arrangement according to claim 1 , wherein the reflector arrangement provides a field of view with an elevation recording angle of at least ±30° and up to ±60°.

6. The reflector arrangement according to claim 1 , wherein:
the sensor is configured to record an image of the projection of the code pattern onto the detection surface, and
the position of the code pattern projectable angle-dependently onto the detection surface can be determined by means of image processing of the image.

7. The reflector arrangement according to claim 1 , wherein the reflector arrangement comprises an evaluation unit, which is adapted to derive a spatial orientation of the reflector arrangement relative to a propagation axis of the radiation entering the retroreflector with respect to at least one degree of freedom with the aid of the position of the projection on the detection surface.

8. The reflector arrangement according to claim 1 , wherein:
the sensor is configured as a monochromatic BSI sensor, or
the sensor is configured as a polarization-resolving sensor, with
different sensor pixels being assigned differently polarization-sensitive matrix elements, and
the sensor providing a calculation of the Stokes vector with the aid of an intensity evaluation of the different sensor pixels.

9. The reflector arrangement according to claim 1 , wherein the reflector arrangement comprises a control unit having a recording functionality, the recording functionality being configured for position-resolved detection of the orientation measurement radiation by means of multiple readout of the sensor, at least a first readout being carried out with measurement information relating to orientation measurement radiation striking the detection surface and a second readout being carried out without this measurement information.

10. A measuring aid instrument having a reflector arrangement according to claim 1 , the measuring aid instrument being configured for contactless or tactile recording of a target point on an object with a defined position reference in relation to the reflector arrangement.

11. A reflector arrangement for position determination or marking target points, the reflector arrangement comprising:
at least one retroreflector, which
provides position determination for the reflector arrangement by means of parallel measurement beam reflection, and
provides a passage surface for at least a part of measurement radiation entering the retroreflector, and

at least one sensor arrangement, arranged downstream of the retroreflector in relation to a measurement beam incidence direction, the sensor arrangement having a sensor for recording measurement radiation passing through the passage surface, the sensor defining an optical axis oriented orthogonally with respect to its detection surface,
wherein:
the sensor arrangement includes a code element having a code pattern, and
the retroreflector, the code element, and the sensor being arranged such that:
the code element is arranged between the retroreflector and the sensor, and
an angle-dependent position with respect to the optical axis of a projection of the code pattern onto the detection surface can be determined by means of the sensor,

wherein the retroreflector is configured as a prism, and the prism comprises:
a light entry surface forming a triangle and,
as an aperture, the passage surface opposite the light entry surface,

wherein the reflector arrangement is configured as a 360° retroreflector having a multiplicity of retroreflector and sensor arrangement pairs, each having a retroreflector and a sensor arrangement as specified above, with
the multiplicity of retroreflectors being arranged next to one another and being configured as prisms,
the multiplicity of retroreflectors numerically corresponding to the number of sensor arrangements, and
each sensor arrangement being assigned to a retroreflector,

wherein
the midpoints of the passage surfaces of the prisms of a first prism group of three prisms lie in a first plane and the midpoints of the passage surfaces of the prisms of a second prism group of three prisms lie in a second plane, and
the first plane and the second plane are oriented parallel to one another.

12. A measuring aid instrument having a reflector arrangement according to claim 11 , the measuring aid instrument being configured for contactless or

Assignees

• Hexagon Technology Ct Gmbh

Inventors

• Jensen Thomas
• Schwendener Andreas
• Stigwall Johan

Classifications

• G01C15/002 Primary

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

• G01S3/7835

  using coding masks · CPC title

• G01S7/481 Primary

  Constructional features, e.g. arrangements of optical elements · CPC title

• G01C15/006 Primary

  Detectors therefor · CPC title

• G01C15/004

  Reference lines, planes or sectors · CPC title