Three dimensional depth mapping using dynamic structured light

Patent metadata

Field	Value
Publication number	US-10091494-B2
Application number	US-201415030851-A
Country	US
Kind code	B2
Filing date	Oct 23, 2014
Priority date	Oct 23, 2013
Publication date	Oct 2, 2018
Grant date	Oct 2, 2018

Abstract

Apparatus for generating a dynamic structured light pattern for optical tracking in three-dimensional space, comprises an array of lasers, such as a VCSEL laser array, to project light in a pattern into a three-dimensional space; and an optical element or elements arranged in cells. The cells are aligned with subsets of the laser array, and each cell individually applies a modulation, in particular an intensity modulation, to light from the laser or lasers of the subset, to provide a distinguishable and separately controllable part of the dynamic structured light pattern. A method of generating a structured light pattern is disclosed, in which light is provided from an array of lasers, and light is individually projected from subsets of the array of lasers to provide differentiated parts of the structured light pattern.

First claim

What is claimed is:

1. An apparatus for generating a structured light pattern, comprising:
an array of lasers arranged to project a light in a pattern into a three-dimensional space, the array of lasers configured to track a three-dimension scene;
a plurality of optical elements wherein each of the optical elements includes a cell, the cells aligned with a subset of the array of lasers such that each cell is individually controllable to dynamically apply a modulation to light passing through the cell to form a distinguishable part of the structured light pattern;
a camera configured to capture one or more images of the scene, the one or more images including at least a portion of the structured light pattern; and
a processor configured to:
analyze the one or more captured images, and
provide one or more instructions, based on the analysis, to one or more of the cells to dynamically adjust the modulation of the light passing through the cell to affect a change in a corresponding part of the structured light pattern.

2. The apparatus of claim 1 , wherein the modulation is one member of the group consisting of a diffractive modulation, a refractive modulation and a combination of a diffractive and a refractive modulation.

3. The apparatus of claim 1 , wherein the optical elements and the subset of the array of lasers comprising a cell are constructed from a single moulded element.

4. The apparatus of claim 1 , wherein a width of the cell is 1 mm or less.

5. The apparatus of claim 1 , wherein a width of the optical element is 1 mm or less.

6. The apparatus of claim 1 , wherein the cells are further controllable in respect of positioning within said structured light pattern and in respect of a shape applied to the light.

7. The apparatus of claim 1 , wherein the dynamically applied modulation applies an increased resolution of the structured light pattern to parts of the scene and applies reduced resolution of the structured light pattern to other parts of the scene.

8. The apparatus of claim 1 , wherein the dynamically applied modulation to the structured light pattern comprises a cellwise change to orientation of the structured light pattern.

9. The apparatus of claim 8 , wherein the dynamically applied modulation is one member of a group consisting of: a change in intensity, a change in polarization, a change in filtering parameters, and a change in focus.

10. The apparatus of claim 1 , wherein the subsets comprise one member of a group consisting of individual lasers, pairs of lasers, triplets of lasers, combinations of different sizes of lasers, and dynamically changing combinations of lasers.

11. The apparatus of claim 1 , wherein light projected from respective subsets is tiled.

12. The apparatus of claim 1 , wherein the laser array comprises a vertical cavity emitting laser array.

13. The apparatus of claim 1 , wherein the laser array comprises a laser bar.

14. The apparatus of claim 1 , incorporated into any member of a group consisting of: a computer, a laptop computer, a mobile communication device, a tablet device, a game console, and a movement capture device.

15. A method of generating a structured light pattern the method comprising:
providing light from an array of lasers, the array of lasers configured to perform three-dimensional tracking;
projecting light from subsets of the array of lasers, the projected light passing through an plurality of optical elements including a respective cell aligned with a subset of the array of lasers, such that the respective cell is individually controllable;
dynamically applying a modulation to the projected light passing through the respective cell to form a distinguishable part of the structured light pattern;
analyzing at least one received captured frame of the scene, the frame comprising a plurality of pixels in a two-dimensional layout; and
responsive to the analysis, dynamically changing the structured light pattern in respective cells based on receiving and analyzing at least one captured frame, the frame comprising a plurality of pixels in a two-dimensional layout.

16. The method of claim 15 , wherein dynamically applying a modulation comprises, applying a modulation to the projected light, the modulation being one member of a group consisting of diffracting, polarizing, changing a wavelength, changing a filtering parameter, changing an intensity.

17. The method of claim 15 , wherein dynamically changing the structured light pattern comprises changing a modulation applied to the projected light from a sub set of the array of lasers.

18. The method of claim 16 , wherein dynamically changing the structured light pattern comprises increasing a resolution level in a part of a scene being tracked and reducing a resolution level in a different part of the scene.

19. The method of claim 16 , wherein dynamically changing the structured light pattern further comprises changing a density of patterning within the structured light.

20. An apparatus for generating a structured light pattern comprising:
an array of lasers arranged to project light in a pattern into a three-dimensional space;
a plurality of cells aligned with respective subsets of the array of lasers wherein each cell is individually controllable and configured to dynamically apply a modulation to light passing through the cell from the respective subset of lasers to provide a distinguishable part of the structured light pattern, the modulation applied by the plurality of cells representing an initial modulation;
a camera configured to capture and transmit one or more frames of the scene, the one or more frames including at least a portion of the structured light pattern; and
a processor configured to:
analyze one or more received captured images;
determine a second modulation configuration based on analyzing at least one captured frame, the second modulation configuration describing a modulation that is different from the initial modulation, and

wherein the plurality of cells are configured to dynamically adjust the modulation of light passing through the cell to apply the second modulation.

Assignees

• Facebook Inc

Inventors

• Romano Nitay
• Grossinger Nadav
• Alpern Yair
• Alon Emil

Classifications

• G06F3/017

  Gesture based interaction, e.g. based on a set of recognized hand gestures (interaction based on gestures traced on a digitiser G06F3/04883) · CPC title

• H04N13/282

  for generating image signals corresponding to three or more geometrical viewpoints, e.g. multi-view systems · CPC title

• G02B27/4205 Primary

  having a diffractive optical element [DOE] contributing to image formation, e.g. whereby modulation transfer function MTF or optical aberrations are relevant · CPC title

• H01S5/423

  having a vertical cavity · CPC title

• H04N13/296 Primary

  Synchronisation thereof; Control thereof · CPC title