DEVICE FOR OPTICALLY SCANNING AND MEASURING AN ENVIRONMENT

• US 20140168379A1
• Filed: 02/14/2013
• Published: 06/19/2014
• Est. Priority Date: 12/14/2012
• Status: Active Grant

• Current Assignee: Faro Technologies Incorporated
• Original Assignee: Faro Technologies Incorporated
• Inventors: Heidemann, Rolf, Ossig, Martin, Becker, Reinhard
• Granted Patent: US 9,599,455 B2
• Time in Patent Office: Days
• US Class Current: 348/47
• CPC Class Codes: G01B 11/002 for measuring two or more coordinates
• CPC Class Codes: G01B 11/2513 with several lines being projected in more than one direction, e.g. grids, patterns
• CPC Class Codes: G01B 11/2531 using several gratings, projected with variable angle of incidence on the object, and one detection device
• CPC Class Codes: G01B 11/2545 with one projection direction and several detection directions, e.g. stereo
• CPC Class Codes: G06T 7/521 from laser ranging, e.g. using interferometry; from the projection of structured light
• CPC Class Codes: G06T 7/593 from stereo images
• CPC Class Codes: H04N 13/243 using three or more 2D image sensors
• CPC Class Codes: H04N 13/25 using two or more image sensors with different characteristics other than in their location or field of view, e.g. having different resolutions or colour pickup characteristics; using image signals from one sensor to control the characteristics of another sensor
• CPC Class Codes: H04N 13/254 in combination with electromagnetic radiation sources for illuminating objects

Abstract

A device for optically scanning and measuring an environment is provided. The device includes at least one projector for producing at least one uncoded pattern on an object in the environment. A first camera is provided for recording at least one first image of the object provided with the pattern, the first camera having a first image plane. A second camera is provided for recording at least one second image of the object provided with the uncoded pattern, the second camera being spaced apart from the first camera in order to acquire the uncoded pattern on a second image plane. A controller is provided having a processor configured to determine the three-dimensional coordinates of points on the surface of the object based at least in part on the uncoded pattern, the at least one first image and the at least one second image.

Claims

1. A device for optically scanning and measuring an environment which comprises:

at least one projector for producing at least one uncoded pattern on an object in the environment;

a first camera for recording at least one first image of the object provided with the uncoded pattern, the first camera having a first image plane;

a second camera for recording at least one second image of the object provided with the uncoded pattern, the second camera being spaced apart from the first camera in order to acquire the uncoded pattern on a second image plane; and

,

a controller having a processor configured to determine a set of three-dimensional coordinates of points on a surface of the object based at least in part on the uncoded pattern, the at least one first image and the at least one second image.

2. The device according to claim 1, wherein the at least one projector, the first camera and the second camera are arranged at a triangle arrangement to each other.

3. The device according to claim 2, wherein:

the at least one projector defines a projector plane;

the at least one projector, the first camera and the second camera, with points of the uncoded pattern, form different epipolar lines in the projector plane and the first image plane and the second image plane.

4. The device according claim 3, wherein:

the at least one projector emits the uncoded pattern monochromatically in an infrared wavelength range by means of a laser; and

the first camera and the second camera include filters that are sensitive in a wavelength range of the uncoded pattern.

5. The device according to claim 4, further comprising a color camera, which records images of the object in a visible wavelength spectrum.

6. The device according to claim 1, wherein the uncoded pattern is a point pattern made of light points.

7. The device according to claim 6, wherein the point pattern forms a grid.

8. The device according to claim 7, wherein the point pattern includes a first plurality of points and a second plurality of points, the second plurality of points being disposed between the first plurality of points.

9. The device according to claim 8, wherein the first plurality of points and the second plurality of points have different intensities

10. The device according to claim 1, wherein the uncoded pattern is a line pattern.

11. The device according to claim 10, wherein the uncoded pattern is a combined pattern of points and lines.

12. The device according to claim 11, wherein the pattern of points having a different intensity from the pattern of lines.

13. The device according to claim 1, wherein the at least one projector is selected from a group comprising:

a diffractive optical element, microlenses, a plurality of single lasers and a projected mask.

14. The device according to claim 1, wherein the at least one projector generates a plurality of patterns in order to change a resolution or point density.

15. The device according to claim 14, wherein the plurality of patterns includes a first pattern and a second pattern, the first pattern being offset with respect to time to the second pattern.

16. The device according to claim 14, wherein the plurality of patterns includes a first pattern and a second pattern, the first pattern having a first optical wavelength and the second pattern having a second optical wavelength

17. The device according to claim 1, wherein:

the at least one projector includes a first projector and a second projector; and

the first projector generates a first pattern and the second projector generates a second pattern.

18. The device according to claim 1, further comprising:

a base member, the at least one projector being arranged in the base member;

a grip member protruding from the base member;

a trigger switch disposed on the grip member; and

a head end on an opposite end of the grip member from the base member, wherein the first camera and the second camera are disposed in the head end.