Chip-scale lidar with a single mems scanner in a compact optical package

Patent metadata

Field	Value
Publication number	US-2019018120-A1
Application number	US-201816019691-A
Country	US
Kind code	A1
Filing date	Jun 27, 2018
Priority date	Jul 12, 2017
Publication date	Jan 17, 2019
Grant date	—

Abstract

A LIDAR system, optical coupler for a LIDAR system and method of optical communication. The LIDAR system includes an optical coupler having a chip-side face in optical communication with a photonic chip and a scanner-side face in optical communication with a scanner, the optical coupler comprising a polarization rotator and a birefringent wedge. A first beam of light is transmitted from the first location toward a chip-side face of an optical coupler to direct the first beam of light, via the optical coupler, along an optical path at a scanner-side face of the optical coupler. A second beam of light is received along the optical path at the scanner-side face and directed the second beam of light toward a second location.

First claim

What is claimed is:

1 . A LIDAR system, comprising:
an optical coupler having a chip-side face in optical communication with a photonic chip and a scanner-side face in optical communication with a scanner, the optical coupler comprising a polarization rotator and a birefringent wedge, wherein the optical coupler directs a first beam of light received at the chip-side face from a first location of the photonic chip toward the scanner along an optical path and directs a second beam of light received at the scanner-side face along the optical path to a second location of the photonic chip.

2 . The LIDAR system of claim 1 , wherein the polarization rotator is a Faraday rotator.

3 . The LIDAR system of claim 1 , wherein the first beam of light enters the birefringent wedge with a polarization direction different from the polarization direction at which the second beam of light entered the birefringent wedge.

4 . The LIDAR system of claim 1 , wherein the first beam of light experiences a first angle of refraction at the birefringent wedge and the second beam of light experiences a second angle of refraction at the birefringent wedge, wherein the difference between the first angle of refraction and the second angle of refraction is due to a difference in the directions of polarization.

5 . The LIDAR system of claim 1 , wherein the optical coupler further comprises collimating optics.

6 . The LIDAR system of claim 1 , wherein the optical coupler further comprises a polarizer at a scanner-side face that polarizes the first beam of light and the second beam of light.

7 . The LIDAR system of claim 3 , further comprising a half-wave plate at the second location for changing a polarization of the second beam of light.

8 . The LIDAR system of claim 1 , wherein the photonic chip transmits the first beam of light from the first location and receives the second beam of light at the second location.

9 . The LIDAR system of claim 1 , wherein the scanner comprises a MEMS scanner in the optical path for directing the first beam of light to a selected point in space and receiving the second beam of light from the selected point in space.

10 . An optical coupler for a LIDAR system, comprising:
a chip-side face in optical communication with a photonic chip; a scanner-side face in optical communication with a scanner; a polarization rotator; and a birefringent wedge; wherein the optical coupler directs a first beam of light received at the chip-side face from a first location of the photonic chip space along an optical path at the scanner and directs a second beam of light received at the scanner-side face along the optical path to a second location of the photonic chip.

11 . The optical coupler of claim 10 , wherein the polarization rotator further comprises a Faraday rotator configured to rotate a polarization of at least the second beam of light, wherein the first beam of light enters the birefringent wedge with a polarization direction different from the polarization direction at which the second beam of light entered the birefringent wedge.

12 . The optical coupler of claim 10 , further includes collimating optics.

13 . The optical coupler of claim 10 , wherein the optical path includes a MEMS scanner that directs the first beam of light to a selected point in space and receives the second beam of light from the selected point in space.

14 . The optical coupler of claim 10 , further comprising a polarizer that polarizes the first beam of light and the second beam of light.

15 . The optical coupler of claim 10 , wherein a half-wave plate at the second location changes a polarization of the incoming second beam of light.

16 . The optical coupler of claim 10 , wherein the first location of the photonic chip includes a laser and the second location includes an edge coupler of the photonic chip.

17 . A method of optical communication, comprising:
transmitting a first beam of light from a first location toward a chip-side face of an optical coupler having a polarization rotator and a birefringent wedge; directing the first beam of light, via the optical coupler, along an optical path at a scanner-side face of the optical coupler; receiving a second beam of light along the optical path at the scanner-side face; and directing the second beam of light toward a second location of the photonic chip at the chip-side face.

18 . The method of claim 17 , wherein the polarization rotator further comprises a Faraday rotator, the method further comprising rotating a polarization of at least the second beam of light at the Faraday rotator, and altering the optical paths of the first beam of light and the second beam of light at the birefringent wedge based on their respective polarizations.

19 . The method of claim 18 , further comprising changing a polarization of the second beam of light at the second location using a half-wave plate.

20 . The method of claim 17 , further comprising steering the first beam of light to a selected point in space using a MEMS scanner in the optical path and receives the second beam of light from the selected point in space.

Assignees

• Gm Global Tech Operations Llc

Inventors

• Efimov Oleg
• Sarkissian Raymond
• Sayyah Keyvan
• Hammon David

Classifications

• G01S7/4817 Primary

  relating to scanning · CPC title

• G02B27/28

  for polarising (used in stereoscopes G02B30/25) · CPC title

• H10W46/607

  Located on parts of packages, e.g. on encapsulations or on package substrates · CPC title

• H10W46/301

  for alignment · CPC title

• H10W46/00

  Marks applied to devices, e.g. for alignment or identification · CPC title