Spatially self-similar patterned illumination for depth imaging
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.
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.