Method for measuring an angle between two spatially separated elements

Patent metadata

Field	Value
Publication number	US-9625255-B2
Application number	US-201314372726-A
Country	US
Kind code	B2
Filing date	Jan 16, 2013
Priority date	Jan 17, 2012
Publication date	Apr 18, 2017
Grant date	Apr 18, 2017

Abstract

Some embodiments of the invention relate to a method for measuring an angle between two spatially separated elements having the steps: preparing a multiplex hologram having a plurality of interference patterns, at least two having different angles of incidence of an object light wave onto a hologram plane; arranging the multiplex hologram in a first element plane on a first element; lighting the multiplex hologram with a reference light wave; arranging a light detector in a second element plane on a second element; detecting a reference light wave refracted on an interference pattern with a light detector; creating an intensity pattern from the detected refracted reference light wave; assigning the angle of incidence stored as machine readable data to the intensity pattern; and/or calculating an angle between the first element plane and the second element plane from the assigned angle of incidence.

First claim

What is claimed is:

1. A method for measuring an angle between two spatially separated elements, the method comprising:
providing a multiplex hologram having multiple interference patterns, at least two interference patterns have different angles of incidence of an object light wave on a hologram plane, the angles of incidence are stored as data in a computer-readable manner;
arranging the multiplex hologram in a first element plane on a first element;
illuminating the multiplex hologram using a reference light wave;
arranging a light detector in a second element plane on a second element;
acquiring a reference light wave, which is diffracted on an interference pattern, using the light detector;
forming an intensity pattern from the acquired diffracted reference light wave;
assigning the computer-readable angle of incidence, which is stored as data, to the intensity pattern; and
calculating an angle between the first element plane and the second element plane from the assigned angle of incidence.

2. The method as claimed in claim 1 , wherein the different angles of incidence are subject to a discrete, non-continuous distribution to one another and a discrete number of independent interference patterns, which may be read out individually, are superimposed in a unit of the multiplex hologram.

3. The method as claimed in claim 1 , wherein an intensity pattern is a flatly extending arrangement of a plurality of shapes, which can be unambiguously differentiated from the remaining surface, wherein an intensity pattern has a machine-readable information content.

4. The method as claimed in claim 3 , wherein the machine readable information content comprises code.

5. The method as claimed in claim 1 , wherein coordinates of the second element plane are specified in a reference coordinate system; coordinates of the assigned angle of incidence are specified in the reference coordinate system;
and the angle is calculated from the difference of the coordinates of the second element plane and the coordinates of the assigned angle of incidence.

6. The method as claimed in claim 1 , wherein a reference coordinate system having an azimuth angle coordinate (θ) and a polar angle coordinate (φ) is used;
and, in step h), the azimuth angle coordinate (θ) and the polar angle coordinate (φ) of the angle are measured simultaneously.

7. The method as claimed in claim 1 , wherein an angle signal is stored as data in a computer-readable manner, which has the angle of incidence and which has an object; and wherein the intensity pattern is compared to the computer-readable data-stored objects; and
in the event of correspondence of the intensity pattern to an object, the angle of incidence of this object is assigned to the intensity pattern.

8. The method as claimed in claim 1 , wherein at least one items of auxiliary information is transmitted from the light source to the light detector the items of auxiliary information is selected from the list consisting of:
a type of the multiplex hologram,
a version of the interference patterns, and
an angle signal.

9. The method as claimed in claim 1 , wherein a two-dimensional barcode is used as the intensity pattern.

10. The method as claimed in claim 9 , wherein an information content of the two-dimensional barcode is read out, this information content specifying the angle of incidence, and this read-out angle of incidence is assigned to the intensity pattern.

11. The method as claimed in claim 9 , wherein the acquired diffracted reference light wave is acquired in a reference coordinate system; and a deviation of a spatial alignment of the two-dimensional barcode to the reference coordinate system is measured as a roll angle (φ′) of the light detector.

12. The method as claimed in claim 1 , wherein the multiplex hologram is illuminated at a constant reference light angle using the reference light wave and/or the multiplex hologram is illuminated at a constant reference light angle by a stationary reference light source using the reference light wave .

13. The method as claimed in claim 1 , wherein the diffracted reference light wave is acquired at a constant light detector angle by a stationary light detector.

14. The method as claimed in claim 1 , wherein a Bragg intensity of the acquired diffracted reference light wave is acquired;
and, if a variation of the Bragg intensity as a function of the acquisition angle is known, an angle of the intensity pattern, which is formed from the acquired diffracted reference light wave, is determined at a higher angle resolution than an angle spacing of the intensity pattern.

15. The method as claimed in claim 1 , wherein a multiplex hologram, which is arranged in the first element plane on the first element, is acquired by multiple light detectors, which are arranged in second element planes on second elements.

16. The method as claimed in claim 15 , wherein an angle between the first element plane and the second element plane is measured from the assigned angle of incidence for each second element.

17. A multiplex hologram comprising:
multiple interference patterns, at least two interference patterns have different angles of incidence of an object light wave on a hologram plane, the angles of incidence are stored as data in a computer-readable manner, wherein the multiplex hologram is arranged in a first element plane on a first element, wherein the multiplex hologram is illuminated using a reference light wave;
a light detector arranged in a second element plane on a second element, wherein the light detector is configured to acquire a reference light wave, which is diffracted on an interference pattern, using the light detector, and wherein an intensity pattern is formed from the acquired diffracted reference light wave;
a computer-readable medium storing an angle of incidence assigned with the intensity pattern; and
a controller that calculates an angle between the first element plane and the second element plane from the assigned angle of incidence.

18. The multiplex hologram according to claim 17 , wherein the first element is embodied in a device selected from the list consisting of:
a mobile scanning device,
a construction machine,
a static object,
a dynamic object,
a coordinate measuring machine, and
a calibration object of a coordinate measuring machine.

19. The multiplex hologram according to claim 17 , wherein
i) the system has a multiplex hologram having multiple interference patterns;
ii) at least two interference patterns of the multiplex hologram have different angles of incidence of an object light wave on a hologram plane; said angles of incidence being stored as data in a computer-readable manner;
iii) the multiplex hologram is arranged in a first element plane on a first element;
iv) the system has a light source, which illuminates the multiplex hologram using a reference light wave;
v) the system has a light detector, which is arranged in a second element plane on a second element; which acquires a reference light wave diffracted on an interference pattern; and which forms an intensity pattern from the acquired diffracted reference light wave; and/or
vi) the system has an analysis unit, which assigns the computer-readable angle of incidence, which is stored as data, to the intensity pattern; and which calculates an angle between the first element plane and the second element plane from the assigned angle of incidence.

20. A computer program product comprising a non-transitory computer-readable medium e

Assignees

• Hexagon Technology Ct Gmbh

Inventors

• Pettersson Bo
• Przygodda Frank
• Siercks Knut

Classifications

• G01B9/021

  using holographic techniques · CPC title

• G03H2001/0033

  in hologrammetry for measuring or analysing · CPC title

• G01B9/02027

  Two or more interferometric channels or interferometers · CPC title

• G03H1/30

  discrete holograms only · CPC title

• G03H1/0005

  Adaptation of holography to specific applications (holographic optical element G02B5/32; holographic scanner G02B26/106; recognition using holographic mask G06V10/88; holographic memories G11B7/0065, G11C13/042) · CPC title