IP Library › Granted Patent US 12,435,968
Granted Patent B2
US 12,435,968 · App. 18/143,820 · Granted Oct 7, 2025

Multiple channel locating

Inventors: Eric Moore (Boulder, CO); Benjamin Braker (Louisville, CO); Daniel Feldkhun (Boulder, CO)
Assignee: Cognex Corporation
G01B11/005G01B11/2518G01B11/2527G01B11/2536G01C3/08G01S7/4815G01S7/4818G01S7/484G01S7/486G01S7/499G01S17/48G01S17/89
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Quick Facts
Patent No.
US 12,435,968
App. No.
18/143,820
Granted
Oct 7, 2025
Kind
B2
Abstract

Methods, systems, and apparatuses are provided for estimating a location on an object in a three-dimensional scene. Multiple radiation patterns are produced by spatially modulating each of multiple first radiations with a distinct combination of one or more modulating structures, each first radiation having at least one of a distinct radiation path, a distinct source, a distinct source spectrum, or a distinct source polarization with respect to the other first radiations. The location on the object is illuminated with a portion of each of two or more of the radiation patterns, the location producing multiple object radiations, each object radiation produced in response to one of the multiple radiation patterns. Multiple measured values are produced by detecting the object radiations from the location on the object due to each pattern separately using one or more detector elements. The location on the object is estimated based on the multiple measured values.

Claims (28)

1. A method comprising:

emitting one or more illumination patterns from a plurality of projectors including:

emitting one or more illumination patterns from a first projector from the plurality of projectors, wherein the one or more illumination patterns from the first projector include a first illumination pattern that illuminates a location on an object; and

emitting one or more illumination patterns from a second projector from the plurality of projectors, wherein the one or more illumination patterns from the second projector include a second illumination pattern that illuminates the location on the object; and

collecting a plurality of object radiations from the location on the object utilizing one or more detecting elements positioned between the first projector and the second projector, wherein collecting the plurality of object radiations includes collecting a first object radiation produced at the location on the object in response to the first illumination pattern and a second object radiation produced at the location on the object in response to the second illumination pattern to estimate the location on the object independently from other locations on the object and to facilitate forming a three-dimensional surface image of the object.

2. The method of claim 1 , wherein emitting the one or more illumination patterns from the first projector includes emitting a set of two or more illumination patterns from the first projector that includes the first illumination pattern and emitting the one or more illumination patterns from the second projector includes emitting a set of two or more illumination patterns from the second projector that includes the second illumination pattern.

3. The method of claim 2 , wherein at least the set of two or more illumination patterns from the first projector are emitted in sequence or the set of two or more illumination patterns from the second projector are emitted in sequence.

4. The method of claim 1 , wherein at least the first illumination pattern from the first projector includes a two-dimensional illumination pattern or the second illumination pattern from the second projector includes a two-dimensional illumination pattern.

5. The method of claim 4 , wherein the two dimensional illumination pattern from at least the first projector or the second projector include a stripe pattern.

6. The method claim 1 , further comprising orienting each projector from the plurality of projectors to project towards the object at a different angle with respect to the other projectors in the plurality of projectors.

7. The method of claim 1 , wherein each projector from the plurality of projectors includes one or more radiation sources.

8. The method of claim 7 , wherein the one or more radiation sources include at least one or more light emitting diodes, one or more laser diodes, or one or more vertical cavity surface emitting laser arrays.

9. The method of claim 1 , wherein at least two projectors from the plurality of projectors operate in sequence.

10. The method of claim 1 , wherein at least two projectors from the plurality of projectors operate simultaneously.

11. The method of claim 1 , wherein the one or more detecting elements includes a charge coupled device.

12. The method of claim 1 , wherein the one or more detecting elements includes a complementary metal-oxide-semiconductor device.

13. The method of claim 1 , wherein each projector from the plurality of projectors includes a pattern mask.

14. The method of claim 1 , wherein each projector from the plurality of projectors modulates an amplitude of radiation from the one or more radiation sources of the respective projector.

15. The method of claim 1 , wherein the one or more illumination patterns from each projector from the plurality of projectors vary across one or more illumination angles for each projector from the plurality of projectors.

16. The method of claim 1 , further comprising estimating the location on the object based on the plurality of object radiations.

17. The method of claim 2 , wherein at least the first projector is reconfigurable to emit the set of two or more illumination patterns from the first projector or the second projector is reconfigurable to emit the set of two or more illumination patterns from the second projector that includes the second illumination pattern.

18. The method of claim 17 , wherein at least the first projector or the second projector is reconfigurable utilizing at least a liquid crystal, a digital micromirror device, a micro-electro-mechanical system array, a photorefractive crystal, or a reconfigurable spatial radiation modulator.

19. The method of claim 1 , wherein emitting the one or more illumination patterns from the first projector from the plurality of projectors further includes emitting one or more illumination patterns from the first projector that illuminate another location on the object that is blocked from being illuminated utilizing the second projector.

20. A system comprising:

a plurality of projectors, wherein each projector from the plurality of projectors emits one or more illumination patterns and the plurality of projectors includes a first projector and a second projector and wherein the first projector emits a first illumination pattern that illuminates a location on an object and the second projector emits a second illumination pattern that illuminates the location on the object and wherein each projector from the plurality of projectors is reconfigurable to emit a plurality of illumination patterns; and

an imaging system that collects a plurality of object radiations from the location on the object that includes collecting a first object radiation produced at the location in response to the first illumination pattern and a second object radiation produced at the location in response to the second illumination pattern to estimate the location on the object independently from other locations on the object and to facilitate forming a three-dimensional surface image of the object, wherein the imaging system includes one or more detecting elements positioned between the first projector and the second projector.

21. The system of claim 20 , wherein the plurality of projectors include at least a liquid crystal, a digital micromirror device, a micro-electro-mechanical system array, a photorefractive crystal, or a reconfigurable spatial radiation modulator.

22. The system of claim 20 , wherein the plurality of projectors include at least one or more light emitting diodes, one or more laser diodes, or one or more vertical cavity surface emitting laser arrays.

Assignments (2)
ASSIGNMENT OF ASSIGNOR'S INTEREST Recorded Sep 7, 2023
From: FELDKHUN, DANIEL; BRAKER, BENJAMIN; MOORE, ERIC DANIEL
To: CHIARO TECHNOLOGIES LLC
Reel/Frame 064825/0157 →
ASSIGNMENT OF ASSIGNOR'S INTEREST Recorded Sep 7, 2023
From: CHIARO TECHNOLOGIES LLC
To: COGNEX CORPORATION
Reel/Frame 064825/0181 →
Continuity (7)
Continuation 16392285 · Apr 23, 2019
Continuation 15607602 · May 29, 2017
Continuation 14455039 · Aug 8, 2014
Continuation 13961397 · Aug 7, 2013
Continuation 12499758 · Jul 8, 2009
Provisional Application 61079128 · Jul 8, 2008
Related Publication 20230392920A1 · Dec 7, 2023
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