Amplification of LIDAR output signals

Patent metadata

Field	Value
Publication number	US-11635491-B2
Application number	US-202016810807-A
Country	US
Kind code	B2
Filing date	Mar 5, 2020
Priority date	Mar 6, 2019
Publication date	Apr 25, 2023
Grant date	Apr 25, 2023

Abstract

A LIDAR system includes a LIDAR chip that generates a LIDAR output signal. The LIDAR chip includes a utility waveguide configured to carry one or more light signals selected from an outgoing LIDAR signal and an incoming LIDAR signal. The system also includes an amplifier that has an amplifier waveguide with a first facet and a second facet. The amplifier being positioned such that the first facet is optically aligned with a facet of the utility waveguide but the second facet is not optically aligned with any waveguide.

First claim

The invention claimed is:

1. A LIDAR system, comprising:
a LIDAR chip that generates a LIDAR output signal, the LIDAR chip including multiple LIDAR chip waveguides on a base, the LIDAR chip waveguides including a utility waveguide configured to carry one or more light signals selected from an outgoing LIDAR signal and an incoming LIDAR signal; and
the LIDAR chip including an amplifier on the base, the amplifier having an amplifier waveguide defined in a gain medium that terminates at a first facet and a second facet, the amplifier being positioned such that the first facet is optically aligned with a facet of the utility waveguide but the second facet is not optically aligned with any of the LIDAR chip waveguides,
the amplifier being included on an amplifier chip that is flip-chip bonded to the LIDAR chip.

2. The system of claim 1 , wherein the LIDAR chip waveguides are integrated on the LIDAR chip.

3. The LIDAR system of claim 1 , wherein the amplifier waveguide receives the outgoing LIDAR signal from the utility waveguide and the amplifier waveguide guides the received outgoing LIDAR signal through the second facet, the amplifier positioned such that the outgoing LIDAR signal exits from the LIDAR chip as a result of passing through the second facet.

4. The LIDAR system of claim 3 , wherein the outgoing LIDAR signal includes multiple wavelength channels.

5. The LIDAR system of claim 1 , wherein the amplifier waveguide receives the incoming LIDAR signal from off the LIDAR chip when the utility waveguide carries the incoming LIDAR signal, the amplifier waveguide guiding the incoming LIDAR signal from the second facet through the first facet, and the utility waveguide receives the incoming LIDAR signal from the amplifier waveguide.

6. The LIDAR system of claim 1 , wherein the amplifier chip is positioned at an edge of the LIDAR chip such that a line can be drawn starting at the second facet and extending away from the amplifier chip in a direction of propagation of the outgoing LIDAR signal at the second facet and without the line passing through any portion of the LIDAR chip.

7. The LIDAR system of claim 1 , wherein the LIDAR chip has the utility waveguide positioned on a base and a level of a top of the amplifier waveguide is between a level of a top of the utility waveguide and a level of the base.

8. The LIDAR system of claim 1 , wherein the facet of the utility waveguide is spaced apart from the first facet.

9. The LIDAR system of claim 1 , wherein the utility waveguide carries both the incoming LIDAR signal and the outgoing LIDAR signal.

10. The LIDAR system of claim 1 , wherein the LIDAR chip is constructed on a silicon-on-insulator platform.

11. The LIDAR system of claim 1 , wherein the second facet is optically aligned with a facet of an optical fiber.

12. The LIDAR system of claim 1 , wherein the facet of the utility waveguide is at an angle between 75° and 85° relative to a direction of propagation of the utility waveguide at the facet of the utility waveguide, and
the amplifier waveguide is curved such that the first facet is at an angle between 75° and 85° relative to a direction of propagation of the amplifier waveguide at the first facet and the second facet is at an angle of 90° relative to a direction of propagation of the amplifier waveguide at the second facet.

13. The LIDAR system of claim 1 , wherein the first facet and the second facet are configured such that the one or more light signals are transmitted through the first facet and the second facet during operation of the LIDAR system.

14. The LIDAR system of claim 1 , wherein the base includes a silicon substrate and the LIDAR chip waveguides and the amplifier waveguide is positioned on the silicon substrate.

15. The LIDAR system of claim 1 , wherein the LIDAR chip includes a signal combining component configured to combine a reference signal with a comparative signal so as to form a composite signal beating at a beat frequency, the comparative signal includes light that has been reflected by an object located outside of the LIDAR system, the reference signal includes light that has not been reflected by any object located outside of the LIDAR system.

16. The LIDAR system of claim 15 , further comprising electronics that calculate LIDAR data from the beat frequency, the LIDAR data indicating a distance and/or radial velocity between the LIDAR system and the object located outside of the LIDAR system.

17. The LIDAR system of claim 15 , wherein the reference signal includes light from the outgoing LIDAR signal and the comparative signal includes light from the outgoing LIDAR signal.

18. A LIDAR system, comprising:
a LIDAR chip that generates a LIDAR output signal, the LIDAR chip including multiple LIDAR chip waveguides on a base, the LIDAR chip waveguides including a utility waveguide configured to carry one or more light signals selected from an outgoing LIDAR signal and an incoming LIDAR signal; and
the LIDAR chip including an amplifier on the base, the amplifier having an amplifier waveguide defined in a gain medium that terminates at a first facet and a second facet, the amplifier being positioned such that the first facet is optically aligned with a facet of the utility waveguide but the second facet is not optically aligned with any of the LIDAR chip waveguides,
the facet of the utility waveguide being at an angle between 75° and 85° relative to a direction of propagation of the utility waveguide at the facet of the utility waveguide, and
the amplifier waveguide being curved such that the first facet is at an angle between 75° and 85° relative to a direction of propagation of the amplifier waveguide at the first facet and the second facet is at an angle of 90° relative to a direction of propagation of the amplifier waveguide at the second facet.

19. The system of claim 18 , wherein the LIDAR chip waveguides are integrated on the LIDAR chip.

20. The LIDAR system of claim 18 , wherein the amplifier waveguide receives the outgoing LIDAR signal from the utility waveguide and the amplifier waveguide guides the received outgoing LIDAR signal through the second facet, the amplifier positioned such that the outgoing LIDAR signal exits from the LIDAR chip as a result of passing through the second facet.

21. The LIDAR system of claim 18 , wherein the amplifier waveguide receives the incoming LIDAR signal from off the LIDAR chip when the utility waveguide carries the incoming LIDAR signal, the amplifier waveguide guiding the incoming LIDAR signal from the second facet through the first facet, and the utility waveguide receives the incoming LIDAR signal from the amplifier waveguide.

22. The LIDAR system of claim 18 , wherein the LIDAR chip has the utility waveguide positioned on a base and a level of a top of the amplifier waveguide is between a level of a top of the utility waveguide and a level of the base.

23. The LIDAR system of claim 18 , wherein the facet of the utility waveguide is spaced apart from the first facet.

24. The LIDAR system of claim 18 , wherein the LIDAR chip is constructed on a silicon-on-insulator platform.

25. The LIDAR system of claim 18 , wherein the second facet is optically aligned with a facet of an optical fiber.

26. The LIDAR system of claim 18 , wherein the LIDAR chip includes a signal combining component configured to combine a reference signal with a comparative signal so as to form a composite signal b

Assignees

• Silc Tech Inc

Inventors

• Asghari Mehdi
• Feng Dazeng
• Luff Bradley Jonathan

Classifications

• G01S17/58 Primary

  Velocity or trajectory determination systems; Sense-of-movement determination systems · CPC title

• G01S7/4814 Primary

  of transmitters alone · CPC title

• H01S5/141

  using a wavelength selective device, e.g. a grating or etalon (H01S5/146 takes precedence) · CPC title

• G01S17/32

  using transmission of continuous waves, whether amplitude-, frequency-, or phase-modulated, or unmodulated · CPC title

• G01S7/4818

  using optical fibres · CPC title