System and method for alignment of optical beams

Patent metadata

Field	Value
Publication number	US-11042004-B1
Application number	US-201715790333-A
Country	US
Kind code	B1
Filing date	Oct 23, 2017
Priority date	Oct 23, 2017
Publication date	Jun 22, 2021
Grant date	Jun 22, 2021

Abstract

Systems and methods can align of one or more optical beams with respect to one another, an optical axis, a far-field location, and/or a near-field location. An example method includes coupling, with an index-matched epoxy, a plurality of adjustable optical surfaces and an optical element. Each adjustable optical surface of the plurality of adjustable optical surfaces is associated with a respective light-emitter device of a plurality of light-emitter devices. Additionally, the method includes causing at least one light-emitter device to emit light that interacts with at least one adjustable optical surface and an optical element to provide a transmitted light beam. The method also includes receiving information about a beam profile of the transmitted light beam, comparing the beam profile to a desired beam profile, and adjusting a position of the at least one adjustable optical surface with respect to the optical element based on the comparison.

First claim

What is claimed is:

1. A system comprising:
a controller comprising at least one processor and a memory, wherein the at least one processor executes program instructions stored in the memory so as to carry out operations, the operations comprising:
coupling, with an index-matched epoxy, a plurality of adjustable optical surfaces and an optical element, wherein each adjustable optical surface of the plurality of adjustable optical surfaces is associated with a respective light-emitter device of a plurality of light-emitter devices;
causing at least one light-emitter device of the plurality of light-emitter devices to emit light that interacts with at least one adjustable optical surface associated with the at least one light-emitter, the index-matched epoxy, device and the optical element to provide a transmitted light beam;
receiving, from a detector, information indicative of a beam profile of the transmitted light beam;
comparing the beam profile to a desired beam profile, wherein the desired beam profile comprises at least a desired beam spot size or a desired beam angle;
while the index-matched epoxy is in a liquid state and while the emitted light interacts with the at least one adjustable optical surface, the index-matched epoxy, and the optical element, adjusting a position of the at least one adjustable optical surface with respect to the optical element based on the comparison; and
when the beam profile corresponds to the desired beam profile, maintaining a position of the at least one adjustable optical surface until the index-matched epoxy is in a solid state.

2. The system of claim 1 , wherein the plurality of light-emitter devices comprises a plurality of laser bars or a plurality of laser bar stacks.

3. The system of claim 1 , wherein the plurality of adjustable optical surfaces comprises at least one of: a plurality of wedge prisms or a plurality of transparent plates.

4. The system of claim 1 , wherein the plurality of adjustable optical surfaces, the optical element, and the index-matched epoxy comprise a same index of refraction when the index-matched epoxy is in the solid state.

5. The system of claim 1 , wherein the detector comprises an image sensor positioned at one of: a near-field location or a far-field location.

6. The system of claim 1 , wherein the optical element comprises at least one of: a lens, an optical diffuser, an end facet of a light guide manifold, or an angled surface of the light guide manifold.

7. A method comprising:
coupling, with an index-matched epoxy, a plurality of adjustable optical surfaces and an optical element, wherein each adjustable optical surface of the plurality of adjustable optical surfaces is associated with a respective light-emitter device of a plurality of light-emitter devices;
causing at least one light-emitter device of the plurality of light-emitter devices to emit light that interacts with at least one adjustable optical surface associated with the at least one light-emitter device, the index-matched epoxy, and the optical element to provide a transmitted light beam;
receiving, from a detector, information indicative of a beam profile of the transmitted light beam;
comparing the beam profile to a desired beam profile, wherein the desired beam profile comprises at least a desired beam spot size or a desired beam angle;
while the index-matched epoxy is in a liquid state and while the emitted light interacts with the at least one adjustable optical surface, the index-matched epoxy, and the optical element, adjusting a position of the at least one adjustable optical surface with respect to the optical element based on the comparison; and
when the beam profile corresponds to the desired beam profile, maintaining a position of the at least one adjustable optical surface until the index-matched epoxy is in a solid state.

8. The method of claim 7 , further comprising:
repeating the method for each light-emitter device of the plurality of light-emitter devices.

9. The method of claim 7 , wherein the plurality of light-emitter devices comprises at least one of a laser bar or a laser bar stack.

10. The method of claim 7 , wherein the plurality of adjustable optical surfaces comprises at least one of: a plurality of wedge prisms or a plurality of transparent plates.

11. The method of claim 7 , wherein the plurality of adjustable optical surfaces, the optical element, and the index-matched epoxy comprise a same index of refraction when the index-matched epoxy is in the solid state.

12. The method of claim 7 , further comprising exposing the index-matched epoxy to UV light so as to cure the index-matched epoxy.

13. The method of claim 7 , wherein the optical element comprises an end facet of a light guide manifold, an angled surface of the light guide manifold, a lens, or an optical diffuser.

14. The method of claim 7 , wherein adjusting a position of the at least one adjustable optical surface comprises causing an actuator to adjust the position of the at least one adjustable optical surface.

15. The system of claim 1 , wherein the desired beam profile corresponds to aligning the transmitted light beam with at least one other transmitted light beam of the plurality of light emitted devices further comprising aligning the transmitted light beam with the at least one other transmitted light beam, wherein aligning the transmitted light beam with the at least one other transmitted light beam comprises adjusting the position of the at least one adjustable optical surface with respect to the optical element based on the comparison.

16. The system of claim 1 , wherein the plurality of adjustable optical elements are separated from the plurality of light emitting devices along an optical beam path, and wherein each adjustable optical element is configured to align a different light beam.

17. The method of claim 7 , wherein the transmitted light beam is a first light beam of a plurality of light beams corresponding to the plurality of light-emitter devices, the method further comprising aligning the plurality of light beams by adjusting respective positions of a plurality of adjustable optical surfaces to provide a plurality of light beams that are aligned with the first light beam and substantially parallel to an optical axis.

18. An optical system prepared by a process comprising the steps of:
coupling, with an index-matched epoxy, a plurality of adjustable optical surfaces and an optical element, wherein each adjustable optical surface of the plurality of adjustable optical surfaces is associated with a respective light-emitter device of a plurality of light-emitter devices;
causing at least one light-emitter device of the plurality of light-emitter devices to emit light that interacts with at least one adjustable optical surface associated with the at least one light-emitter device, the index-matched epoxy, and the optical element to provide a transmitted light beam;
receiving, from a detector, information indicative of a beam profile of the transmitted light beam;
comparing the beam profile to a desired beam profile, wherein the desired beam profile comprises at least a desired beam spot size or a desired beam angle;
while the index-matched epoxy is in a liquid state and while the emitted light interacts with the at least one adjustable optical surface, the index-matched epoxy, and the optical element, adjusting a position of the at least one adjustable optical surface with respect to the optical element based on the comparison; and
when the beam profile corresponds to the desired beam profile,

Assignees

• Waymo Llc

Inventors

• Shepard Ralph
• Droz Pierre-Yves

Classifications

• G01S17/894

  Three-dimensional [3D] imaging with simultaneous measurement of time-of-flight at a two-dimensional [2D] array of receiver pixels, e.g. time-of-flight cameras or flash lidar · CPC title

• G01S17/931

  of land vehicles · CPC title

• G01S7/4815

  using multiple transmitters · CPC title

• F16B11/006

  by gluing (gluing of plastics material B29C65/48) · CPC title

• G02B27/62 Primary

  Optical apparatus specially adapted for adjusting optical elements during the assembly of optical systems · CPC title