US 12,288,362 B2
Active alignment of an optical assembly with intrinsic calibration
Nijumudheen Muhassin, Pittsburgh, PA (US); Jayesh Dwivedi, Pittsburgh, PA (US); and Yew Kwang Low, Singapore (SG)
Assigned to MOTIONAL AD LLC, Boston, MA (US)
Filed by Motional AD LLC, Boston, MA (US)
Filed on Jan. 21, 2022, as Appl. No. 17/581,712.
Prior Publication US 2023/0237701 A1, Jul. 27, 2023
Int. Cl. G06T 7/80 (2017.01); G01M 11/02 (2006.01); G01S 7/40 (2006.01); G01S 13/86 (2006.01); G01S 13/931 (2020.01); G01S 17/86 (2020.01); G02B 7/00 (2021.01); G02B 27/30 (2006.01); G02B 27/42 (2006.01); G03B 5/00 (2021.01); G05D 1/00 (2024.01); G01S 7/497 (2006.01)
CPC G06T 7/80 (2017.01) [G02B 27/30 (2013.01); G01S 7/4004 (2013.01); G01S 7/497 (2013.01); G01S 13/865 (2013.01); G01S 13/867 (2013.01); G01S 17/86 (2020.01); G06T 2207/30244 (2013.01)] 20 Claims
OG exemplary drawing
 
1. A method, comprising:
positioning, using at least one processor, a lens of a camera assembly on a first stage and positioning an image sensor of the camera assembly on a second stage, wherein one or more of the first and second stages are configured to adjust a relative position of the lens and the image sensor;
projecting, using the at least one processor, from a multi-collimator assembly, a plurality of targets through the lens and onto the image sensor such that the plurality of targets is visible in a first image captured by the image sensor;
adjusting, using the at least one processor, the relative position of one or more of the lens and the image sensor using one or more of the first and second stages to perform a first active alignment of the camera assembly based on the first image captured;
moving, using the at least one processor, a diffractive optical element (DOE) intrinsic calibration module into an optical path of the camera assembly, wherein the DOE intrinsic calibration module is configured to project a grid of points onto the image sensor such that the grid of points is visible in a second image captured by the image sensor;
determining, using the at least one processor, a principal point of the camera assembly based on the second image;
moving, using the at least one processor, the DOE intrinsic calibration module out of the optical path of the camera assembly such that the multi-collimator assembly projects the plurality of targets through the lens and onto the image sensor such that the plurality of targets is visible in a third image captured by the image sensor; and
further adjusting, using the at least one processor, the relative position of one or more of the lens and the image sensor using one or more of the first and second stages to align the principal point of the camera assembly with an image center of the image sensor and to perform a second active alignment based on the third image.