Spatially self-similar patterned illumination for depth imaging

Patent metadata

Field	Value
Publication number	US-11054506-B2
Application number	US-202016845737-A
Country	US
Kind code	B2
Filing date	Apr 10, 2020
Priority date	Mar 10, 2014
Publication date	Jul 6, 2021
Grant date	Jul 6, 2021

Abstract

Methods, systems, and devices involving patterned radiation are provided in accordance with various embodiments. Some embodiments include a device for projecting pattern radiation. Some embodiments include a method for estimating coordinates of a location on an object in a 3D scene. Some embodiments include a system for estimating the coordinates of a location on an object in a 3D scene. A variety of radiation patterns are provided in accordance with various embodiments. Some embodiments may relate to the use of patterned illumination to identify the angular information that may be utilized to measure depth by triangulation.

First claim

What is claimed is:

1. A method for estimating coordinates of a location on an object in a 3D scene, the method comprising:
illuminating at least a portion of the 3D scene with a radiation pattern, wherein the radiation pattern includes:
a plurality of spatial symbols, wherein each spatial symbol from the plurality of spatial symbols comprises a radiation distribution such that at least one characteristic of the radiation distribution varies spatially and wherein the plurality of spatial symbols are configured such that:
each respective spatial symbol from the plurality of spatial symbols is distinguishable from the other spatial symbols from the plurality of spatial symbols; and
each respective spatial symbol from the plurality of spatial symbols is related to a one or more master spatial symbols

detecting the radiation pattern illuminating at least the portion of the illuminated 3D scene using one or more radiation detectors; and
estimating the coordinates of the location on the object based on the detected radiation pattern.

2. The method of claim 1 , wherein the plurality of spatial symbols includes a plurality of arrangements of the plurality of spatial symbols.

3. The method of claim 2 , wherein the plurality of arrangements of the plurality of spatial symbols includes a first arrangement of the plurality of spatial symbols and a second arrangement of the plurality of spatial symbols.

4. The method of claim 3 , wherein the second arrangement of the plurality of spatial symbols is a repetition of the first arrangement of the plurality of spatial symbols.

5. The method of claim 4 , wherein the second arrangement of the plurality of spatial symbols is arranged along a first direction with respect to the first arrangement of the plurality of spatial symbols along a first linear dimension.

6. The method of claim 5 , wherein the second arrangement of the plurality of spatial symbols is arranged along a second direction with respect to the first arrangement of the plurality of spatial symbols.

7. The method of claim 3 , wherein the second arrangement of the plurality of spatial symbols is a repetition of the first arrangement of the plurality of spatial symbols with a shift applied to the plurality of spatial symbols of the first arrangement of the plurality of spatial symbols to form the second arrangement of the plurality of symbols.

8. The method of claim 7 , wherein the shift applied to the plurality of spatial symbols of the first arrangement of the plurality of spatial symbols to form the second arrangement of the plurality of symbols is performed on a row-to-row basis.

9. The method of claim 7 , wherein the shift applied to the plurality of spatial symbols of the first arrangement of the plurality of spatial symbols to form the second arrangement of the plurality of symbols is less than a symbol width.

10. The method of claim 3 , wherein the second arrangement of the plurality of spatial symbols includes the same symbols from the first arrangement of the plurality of spatial symbols in a different order from the first arrangement of the plurality of spatial symbols.

11. The method of claim 1 , wherein the plurality of spatial symbols includes one or more spatial symbols from the plurality of spatial symbols that is repeated.

12. The method of claim 1 , wherein the plurality of spatial symbols includes one or more spatial symbols from the plurality of spatial symbols that is rotated.

13. The method of claim 1 , wherein the plurality of spatial symbols includes one or more spatial symbols from the plurality of spatial symbols that is distorted.

14. The method of claim 1 , wherein the plurality of spatial symbols includes two or more spatial symbols from the plurality of spatial symbols that are arranged to overlap each other.

15. The method of claim 1 , wherein one or more of the plurality of spatial symbols is distorted to compensate for distortion introduced through a projection lens.

16. The method of claim 1 , wherein the one or more master symbols includes a plurality of master symbols.

17. The method of claim 3 , wherein illuminating at least the portion of the 3D scene with the radiation pattern utilizes a plurality of projectors.

18. The method of claim 1 , further comprising at least pulsing or strobing the plurality of projectors.

19. The method of claim 1 , further comprising detecting one or more errors with respect to the detected radiation pattern.

Assignees

• Cognex Corp

Inventors

• Braker Benjamin
• Wegner Aaron
• Zimmerman Ronald
• Moore Eric
• Mcdonald Trevor

Classifications

• G01B11/2531 Primary

  using several gratings, projected with variable angle of incidence on the object, and one detection device · CPC title

• G01S17/42

  Simultaneous measurement of distance and other co-ordinates (indirect measurement G01S17/46) · CPC title

• G06T2207/20056

  Discrete and fast Fourier transform, [DFT, FFT] · CPC title

• G01S7/4814 Primary

  of transmitters alone · CPC title

• G06T7/521

  from laser ranging, e.g. using interferometry; from the projection of structured light · CPC title