Structured light pattern generation

Patent metadata

Field	Value
Publication number	US-9817159-B2
Application number	US-201514611197-A
Country	US
Kind code	B2
Filing date	Jan 31, 2015
Priority date	Jan 31, 2015
Publication date	Nov 14, 2017
Grant date	Nov 14, 2017

Abstract

A pattern projector disclosed herein generates and projects a structured light pattern suitable for use in a variety of active depth sensing technologies. In one implementation, a structured light pattern is generated by directing a coherent light beam through a pseudorandom diffuser element. Output of the pseudorandom diffuser element is received by a relay optic configured to spatially filter incident light to generate an output speckle illumination and to project the output speckle illumination to a three-dimensional scene.

First claim

What is claimed is:

1. A system comprising:
a pseudorandom diffuser element configured to receive a non-collimated coherent light input and to scatter the coherent light input to output intermediate speckle illumination; and
a relay optic positioned to receive the intermediate speckle illumination from the pseudorandom diffuser element, the relay optic being configured to spatially filter the intermediate speckle illumination to generate an output speckle illumination.

2. The system of claim 1 wherein a light source is configured to project the non-collimated coherent light input through a first surface of the pseudorandom diffuser element and the intermediate speckle illumination is to be output through a second opposite surface of the pseudorandom diffuser element.

3. The system of claim 1 wherein a light source is configured to project the non-collimated coherent light input through a first surface of the pseudorandom diffuser element and the intermediate speckle illumination is to be output through a second surface of the pseudorandom diffuser element, the second surface oriented substantially perpendicular to the first surface.

4. The system of claim 1 wherein the pseudorandom diffuser element includes at least one transparent rough surface to receive the non-collimated coherent light input.

5. The system of claim 4 , wherein the rough surface has an increased roughness in an area proximal to a source of the non-collimated coherent light input and a decreased roughness in an area distal to the source of the coherent light input.

6. The system of claim 1 , further comprising:
a sensor configured to detect the output speckle illumination reflected on objects in a three-dimensional scene.

7. The system of claim 6 , further comprising:
a processor configured to generate a depth map of the three-dimensional scene based on data collected by the sensor.

8. The system of claim 1 wherein the non-collimated coherent light input is generated by a laser.

9. A method comprising:
directing a non-collimated coherent light beam through a pseudorandom diffuser element to scatter the coherent light input to output an intermediate speckle illumination; and
directing the intermediate speckle illumination through a relay optic, the relay optic spatially filtering the intermediate speckle illumination to generate an output speckle illumination.

10. The method of claim 9 wherein a light source projects the non-collimated coherent light beam through a first surface of the pseudorandom diffuser element and the intermediate speckle illumination is output through a second opposite surface of the pseudorandom diffuser element.

11. The method of claim 9 wherein a light source projects the non-collimated coherent light beam through a first surface of the pseudorandom diffuser element and the intermediate speckle illumination is output through a second surface of the pseudorandom diffuser element, the second surface oriented substantially perpendicular to the first surface.

12. The method of claim 9 further comprising:
projecting the output speckle illumination to a three-dimensional scene; and
detecting, with a sensor, the output speckle illumination reflected on objects in the three-dimensional scene.

13. The method of claim 9 further comprising:
generating a depth map of the three-dimensional scene based on data collected by the sensor.

14. The method of claim 9 wherein directing the non-collimated coherent light beam through the pseudorandom diffuser element further comprises:
directing the coherent light beam though a rough surface.

15. The method of claim 9 wherein the intermediate speckle illumination includes a different light interference pattern than the output speckle illumination.

16. The method of claim 9 wherein the relay optic has an f-number selected to generate the output speckle illumination of a predetermined resolution.

17. A system comprising:
a relay optic positioned to receive non-collimated coherent intermediate speckle illumination from a pseudorandom diffuser element, the relay optic being configured to spatially filter the light and to project the spatially filtered light to a three-dimensional scene; and
a sensor configured to detect the spatially-filtered light from the three-dimensional scene; and
a processor configured to calculate a depth map of the three-dimensional scene based on data collected by the sensor.

18. The system of claim 17 wherein the light is IR light and the sensor is an IR sensor.

19. The system of claim 18 wherein the rough surface includes areas of uneven roughness.

20. The system of claim 17 wherein the pseudorandom diffuser element includes a rough surface and changing the rough surface changes a sampling of the spatially filtered light.

Assignees

• Microsoft Technology Licensing Llc

Inventors

• Hudman Josh

Classifications

• G01B11/2513 Primary

  with several lines being projected in more than one direction, e.g. grids, patterns · CPC title

• G02B5/0221 Primary

  the surface having an irregular structure (G02B5/0226 takes precedence) · CPC title

• G02B27/48

  Laser speckle optics · CPC title

• G01B11/14

  for measuring distance or clearance between spaced objects or spaced apertures (G01B11/26 takes precedence; rangefinders G01C3/00) · CPC title

• G02B5/0263

  with positional variation of the diffusing properties, e.g. gradient or patterned diffuser · CPC title