Illuminator for camera system having three dimensional time-of-flight capture with movable mirror element

• US 9,854,226 B2
• Filed: 12/22/2014
• Issued: 12/26/2017
• Est. Priority Date: 12/22/2014
• Status: Active Grant

• Current Assignee: Google LLC (Alphabet Inc.)
• Original Assignee: Google Inc. (Alphabet Inc.)
• Inventors: Ko, Jamyuen, Wan, Chung Chun
• Primary Examiner(s): Walker, Jared
• Application Number:
  US14/580,053
• Publication Number:
  US 20160182892A1
• Time in Patent Office: 1,100 Days
• Field of Search: 348 46
• CPC Class Codes: G01S 17/894 3D imaging with simultaneous measurement of time-of-flight at a 2D array of receiver pixels, e.g. time-of-flight cameras or flash lidar
• CPC Class Codes: G01S 7/4815 using multiple transmitters
• CPC Class Codes: G01S 7/4817 relating to scanning
• CPC Class Codes: H04N 13/254 in combination with electromagnetic radiation sources for illuminating objects
• CPC Class Codes: H04N 13/286 having separate monoscopic and stereoscopic modes
• CPC Class Codes: H04N 13/296 Synchronisation thereof; Control thereof
• CPC Class Codes: H04N 2213/001 Constructional or mechanical details
• CPC Class Codes: H04N 23/56 provided with illuminating means

Abstract

An apparatus is described that includes a camera system having a time-of-flight illuminator. The time of flight illuminator has a light source and one or more tiltable mirror elements. The one or more tiltable mirror elements are to direct the illuminator'"'"'s light to only a region within the illuminator'"'"'s field of view.

Claims

1. An apparatus, comprising:

a camera system comprising a time-of-flight illuminator, said time of flight illuminator comprising a light source and a plurality of tiltable mirror elements, the plurality of tiltable mirror elements to direct the time-of-flight illuminator'"'"'s light to only a region within the time-of-flight illuminator'"'"'s field of view, the plurality of tiltable mirror elements being individually tiltable at different angles in order to concentrate the time-of-flight illuminator'"'"'s light within the region by overlapping different rays of the time-of-flight illuminator'"'"'s light within the region after reflection of the different rays from different respective ones of the plurality of tiltable mirror elements, the time-of-flight illuminator not including an optical component along an optical path that emanates from the plurality of tiltable mirror elements to concentrate the light that is reflected from the plurality of tiltable mirror elements.

2. The apparatus of claim 1 wherein the plurality of tiltable mirror elements comprises a MEMs device.

3. The apparatus of claim 1 wherein the light source further comprises a plurality of light source devices.

4. The apparatus of claim 3 wherein the light source devices are arranged in an array.

5. The apparatus of claim 3 wherein the light source devices are VCSELs.

6. The apparatus of claim 3 wherein the light source devices are LEDs.

7. The apparatus of claim 1 wherein the light source is affixed to an underside of an arm that extends to a vertical height that resides above the plurality of tiltable mirror elements.

8. The apparatus of claim 1 wherein said illuminator further comprises a turntable motor that is mechanically coupled to said one or more tiltable mirrors.

9. A method, comprising:

performing the following with a time-of-flight camera system illuminator;

emitting light from a light source and impinging said light upon a plurality of tiltable mirrors;

tilting said plurality of tiltable mirrors to reflect said light to only a region of said illuminator'"'"'s field of view, said tilting comprising individually tilting said plurality of tiltable mirrors at different angles in order to concentrate said light within said region by overlapping different rays of the light within the region after reflection of the different rays from different respective ones of the plurality of tiltable mirror elements; and

,

directing said light after said light has been reflected from said plurality of tiltable mirrors through an exit of said time-of-flight camera system illuminator without passing said light through an optical component that concentrates the light that has been reflected from the plurality of tiltable mirrors.

10. The method of claim 9 wherein said plurality of tiltable mirrors comprises a MEMS device.

11. The method of claim 9 wherein said method further comprises spinning said plurality of tiltable mirrors.

12. A computing system, comprising:

an applications processor, said applications processor comprising a plurality of processing cores and a memory controller, said memory controller coupled to a system memory;

a 2D/3D camera system coupled to said applications processor, said 2D/3D camera system comprising a time-of-flight illuminator, said time of flight illuminator having a light source and a plurality of tiltable mirror elements, the plurality of tiltable mirror elements to direct the illuminator'"'"'s light to only a region within the illuminator'"'"'s field of view, the time-of-flight illuminator not including an optical component along an optical path that emanates from the plurality of tiltable mirror elements, the plurality of tiltable mirror elements to concentrate the light that is reflected from the plurality of tiltable mirror elements within the region by overlapping different rays of the light within the region after reflection of the different rays from different respective ones of the plurality of tiltable mirror elements.

13. The computing system of claim 12 wherein the plurality of tiltable mirror elements comprises a MEMs device.

14. The apparatus of claim 12 wherein the light source is affixed to an underside of an arm that extends to a vertical height that resides above the plurality of tiltable mirror elements.

15. The apparatus of claim 12 wherein the illuminator further comprises a turntable motor that is mechanically coupled to the plurality of tiltable mirrors.