US 11,686,935 B2
Interferometric structured illumination for depth determination
Qing Chao, Redmond, WA (US); and Zhaoming Zhu, Redmond, WA (US)
Assigned to Meta Platforms Technologies, LLC, Menlo Park, CA (US)
Filed by Meta Platforms Technologies, LLC, Menlo Park, CA (US)
Filed on Jan. 29, 2019, as Appl. No. 16/261,531.
Prior Publication US 2022/0413284 A1, Dec. 29, 2022
Int. Cl. G02B 27/00 (2006.01); G06F 3/01 (2006.01); G01B 11/22 (2006.01); G01B 11/25 (2006.01); H04N 23/56 (2023.01); H04N 23/74 (2023.01); G02B 27/01 (2006.01)
CPC G02B 27/0093 (2013.01) [G01B 11/22 (2013.01); G01B 11/25 (2013.01); G06F 3/013 (2013.01); H04N 23/56 (2023.01); H04N 23/74 (2023.01); G02B 27/0172 (2013.01); G02B 2027/0138 (2013.01); G02B 2027/0178 (2013.01)] 20 Claims
OG exemplary drawing
 
1. A depth camera assembly (DCA) comprising:
a light source assembly comprising a plurality of light sources, wherein (i) each light source of the plurality of light sources is configured to emit light and (ii) the plurality of light sources comprises a respective light source, wherein each light source of the plurality of light sources emits light at a same wavelength and is assigned to groups that can have two potential states:
an active state where light sources in the group emit light,
an inactive state where no light source in the group emits light, and
wherein for a given time period only one group is in an active state and any remaining groups are in the inactive state;
a mask comprising two adjacent openings that are unobstructed holes in the mask and are configured to pass through light emitted by the light source assembly, wherein the light emitted by the respective light source that is passed through a first opening of the two adjacent openings interferes with the light emitted by the respective light source that is passed through a second opening of the two adjacent openings to form an interference pattern across a target area, the interference pattern having a phase based on a position of the respective light source, and the light from each light source generates a respective interference pattern across the target area;
a camera assembly configured to capture images of a portion of the target area that includes the interference pattern; and
a controller configured to determine depth information for the portion of the target area based on the captured images.