US 12,299,932 B2
Compensation of three-dimensional measuring instrument having an autofocus camera
Martin Ossig, Tamm (DE); and Johannes Buback, Korntal-Munchingen (DE)
Assigned to FARO Technologies, Inc., Lake Mary, FL (US)
Filed by FARO Technologies, Inc., Lake Mary, FL (US)
Filed on Sep. 18, 2023, as Appl. No. 18/369,658.
Application 18/369,658 is a continuation of application No. 17/813,630, filed on Jul. 20, 2022, granted, now 11,763,491.
Application 17/813,630 is a continuation in part of application No. 17/076,070, filed on Oct. 21, 2020, granted, now 11,481,917, issued on Oct. 25, 2022.
Prior Publication US 2024/0087167 A1, Mar. 14, 2024
Int. Cl. G06T 7/80 (2017.01); G06T 7/521 (2017.01); G06T 7/571 (2017.01); H04N 23/56 (2023.01); H04N 23/67 (2023.01)
CPC G06T 7/80 (2017.01) [G06T 7/521 (2017.01); G06T 7/571 (2017.01); H04N 23/56 (2023.01); H04N 23/67 (2023.01); G06T 2207/10148 (2013.01); G06T 2207/30204 (2013.01)] 18 Claims
OG exemplary drawing
 
13. A measurement instrument apparatus, comprising:
a registration camera;
an autofocus camera having an autofocus mechanism configured to adjust a focal length of the autofocus camera;
at least one processor; and
an electronic memory storing programming instructions for execution by the at least one processor to:
capture with the registration camera at a first time, a first registration image of a first plurality of feature points corresponding to surface points on a surface of an object in an environment;
simultaneously capture with the autofocus camera a first surface image that corresponds to the first registration image;
determine, for each of the first plurality of feature points, a plurality of three-dimensional (3D) coordinates of corresponding surface points on the object based at least in part on the first surface image;
capture with the registration camera at a second time a second registration image of a second plurality of feature points substantially corresponding to the first plurality of feature points;
adjust with the autofocus mechanism the focal length of the autofocus camera to reduce a difference between positions of the first plurality of feature points and the second plurality of feature points;
capture a second surface image of the object with the autofocus camera having the focal length;
determine a compensation parameter based at least in part on the second surface image; and
store, in the electronic memory, the determined compensation parameter for use with adjusting feature points captured in additional images,
wherein the autofocus camera is an infrared camera and the first surface image and the second surface image are infrared images.