Limitation of noise on light detectors using an aperture

Patent metadata

Field	Value
Publication number	US-11921206-B2
Application number	US-202218057463-A
Country	US
Kind code	B2
Filing date	Nov 21, 2022
Priority date	Oct 13, 2016
Publication date	Mar 5, 2024
Grant date	Mar 5, 2024

Abstract

The present disclosure relates to limitation of noise on light detectors using an aperture. One example embodiment includes a system. The system includes a lens disposed relative to a scene and configured to focus light from the scene onto a focal plane. The system also includes an aperture defined within an opaque material disposed at the focal plane of the lens. The aperture has a cross-sectional area. In addition, the system includes an array of light detectors disposed on a side of the focal plane opposite the lens and configured to intercept and detect diverging light focused by the lens and transmitted through the aperture. A cross-sectional area of the array of light detectors that intercepts the diverging light is greater than the cross-sectional area of the aperture.

First claim

What is claimed:

1. A system, comprising:
a lens disposed relative to a scene, wherein the lens is configured to focus light from the scene;
an opaque material, wherein the opaque material defines a plurality of apertures; and
an array of light detectors arranged to intercept diverging light, wherein the diverging light comprises light from the scene focused by the lens that diverges from at least one aperture of the plurality of apertures.

2. The system of claim 1 , wherein the lens is configured to focus the light from the scene onto a focal plane, and wherein the opaque material is disposed at or near the focal plane of the lens.

3. The system of claim 1 , wherein the plurality of apertures comprises at least a first aperture having a first size and a second aperture having a second size, wherein the second size is different than the first size.

4. The system of claim 3 , wherein the first and second apertures are circular.

5. The system of claim 4 , wherein the first aperture has a first radius and the second aperture has a second radius, wherein the second radius is different than the first radius.

6. The system of claim 3 , wherein the plurality of apertures further comprises a third aperture having a third size, wherein the third size is different than the first size and different than the second size.

7. The system of claim 1 , wherein the array of light detectors comprises a plurality of single photon avalanche diodes (SPADs).

8. The system of claim 1 , wherein each aperture of the plurality of apertures has a respective cross-sectional area that is less than a cross-sectional area of the array of light detectors.

9. The system of claim 1 , wherein the opaque material is movable with respect to the lens and the array of light detectors.

10. The system of claim 1 , further comprising:
an optical filter associated with at least one aperture of the plurality of apertures.

11. The system of claim 10 , wherein the optical filter selectively transmits light within a wavelength range.

12. The system of claim 1 , further comprising:
one or more mirrors, wherein the one or more mirrors are adjustable to direct the light from the scene focused by the lens toward a specific aperture of the plurality of apertures.

13. The system of claim 12 , wherein the one or more mirrors comprise microelectromechanical systems (MEMS) mirrors.

14. A method comprising:
focusing, by a lens disposed relative to a scene, light from the scene;
transmitting the focused light through at least one aperture of a plurality of apertures defined within an opaque material;
intercepting, by an array of light detectors, diverging light, wherein the diverging light comprises light from the scene focused by the lens that diverges from the at least one aperture of the plurality of apertures; and
detecting, by the array of light detectors, the intercepted light.

15. A light detection and ranging (LIDAR) device comprising:
a LIDAR transmitter configured to illuminate a scene with light;
a LIDAR receiver configured to receive light reflected by one or more objects within the scene, wherein the LIDAR receiver comprises:
a lens configured to focus the reflected light from the scene;
an opaque material, wherein the opaque material defines a plurality of apertures; and
an array of light detectors arranged to intercept diverging light, wherein the diverging light comprises light from the scene focused by the lens that diverges from at least one aperture of the plurality of apertures.

16. The LIDAR device of claim 15 , wherein the plurality of apertures comprises at least a first aperture having a first size and a second aperture having a second size, wherein the second size is different than the first size.

17. The LIDAR device of claim 16 , wherein the first and second apertures are circular.

18. The LIDAR device of claim 17 , wherein the first aperture has a first radius and the second aperture has a second radius, wherein the second radius is different than the first radius.

19. The LIDAR device of claim 15 , wherein the array of light detectors comprises a plurality of single photon avalanche diodes (SPADs).

20. The LIDAR device of claim 15 , wherein each aperture of the plurality of apertures has a respective cross-sectional area that is less than a cross-sectional area of the array of light detectors.

Assignees

• Waymo Llc

Inventors

• Droz Pierre-Yves
• Gassend Blaise
• Onal Caner
• Hutchison David

Classifications

• G01S17/08 Primary

  for measuring distance only (indirect measurement G01S17/46; active triangulation systems G01S17/48) · CPC title

• G01J1/0411 Primary

  using focussing or collimating elements, i.e. lenses or mirrors; Aberration correction · CPC title

• G01J1/0414

  using plane or convex mirrors, parallel phase plates, or plane beam-splitters · CPC title

• G01J1/0422

  using light concentrators, collectors or condensers · CPC title

• G01J1/0437

  using masks, aperture plates, spatial light modulators, spatial filters, e.g. reflective filters · CPC title